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ALS References 2003 (101 References) Al-Chalabi, A. and C. C. Miller (2003). "Neurofilaments and neurological disease." Bioessays 25(4): 346-55. Neurofilaments are one of the major components of the neuronal cytoskeleton and are responsible for maintaining the calibre of axons. They are modified by post-translational changes that are regulated in complex fashions including by the interaction with neighbouring glial cells. Neurofilament accumulations are seen in several neurological diseases and neurofilament mutations have now been associated with Charcot-Marie-Tooth disease, Parkinson's disease and amyotrophic lateral sclerosis. In this review, we discuss the structure, normal function and molecular pathology of neurofilaments. BioEssays 25:346-355, 2003.
Allen, S., P. R. Heath, et al. (2003). "Analysis of the cytosolic proteome in a cell culture model of familial amyotrophic lateral sclerosis reveals alterations to the proteasome, antioxidant defenses, and nitric oxide synthetic pathways." J Biol Chem 278(8): 6371-83. Injury to motor neurons associated with mutant Cu,Zn-superoxide dismutase (SOD1)-related familial amyotrophic lateral sclerosis (FALS) results from a toxic gain-of-function of the enzyme. The mechanisms by which alterations to SOD1 elicit neuronal death remain uncertain despite intensive research effort. Analysis of the cellular proteins that are differentially expressed in the presence of mutant SOD1 represents a novel approach to investigate further this toxic gain-of-function. By using the motor neuron-like cell line NSC34 stably transfected with wild-type, G93A, or G37R mutant human SOD1, we investigated the effects of mutant human SOD1 on protein expression using proteomic approaches. Seven up-regulated proteins were identified as argininosuccinate synthase, argininosuccinate lyase, neuronal nitric-oxide synthase, RNA-binding motif protein 3, peroxiredoxin I, proteasome subunit beta 5 (X), and glutathione S-transferase (GST) Alpha 2. Seven down-regulated proteins were identified as GST Mu 1, GST Mu 2, GST Mu 5, a hypothetical GST Mu, GST Pi B, leukotriene B(4) 12-hydroxydehydrogenase, and proteasome subunit beta5i (LMP7). GST assays demonstrated a significant reduction in the total GST activity of cells expressing mutant human SOD1. Proteasome assays demonstrated significant reductions in chymotrypsin-like, trypsin-like, and post-glutamylhydrolase proteasome activities. Laser capture microdissection of spinal cord motor neurons from human FALS cases, in conjunction with reverse transcriptase-PCR, demonstrated decreased levels of mRNA encoding GST Mu 1, leukotriene B(4) 12-hydroxydehydrogenase, and LMP7. These combined approaches provide further evidence for involvement of alterations in antioxidant defenses, proteasome function, and nitric oxide metabolism in the pathophysiology of FALS.
Angelov, D. N., S. Waibel, et al. (2003). "Therapeutic vaccine for acute and chronic motor neuron diseases: Implications for amyotrophic lateral sclerosis." Proc Natl Acad Sci U S A. Therapeutic vaccination with Copaxone (glatiramer acetate, Cop-1) protects motor neurons against acute and chronic degenerative conditions. In acute degeneration after facial nerve axotomy, the number of surviving motor neurons was almost two times higher in Cop-1-vaccinated mice than in nonvaccinated mice, or in mice injected with PBS emulsified in complete Freund's adjuvant (P < 0.05). In mice that express the mutant human gene Cu/Zn superoxide dismutase G93A (SOD1), and therefore simulate the chronic human motor neuron disease amyotrophic lateral sclerosis, Cop-1 vaccination prolonged life span compared to untreated matched controls, from 211 +/- 7 days (n = 15) to 263 +/- 8 days (n = 14; P < 0.0001). Our studies show that vaccination significantly improved motor activity. In line with the experimentally based concept of protective autoimmunity, these findings suggest that Cop-1 vaccination boosts the local immune response needed to combat destructive self-compounds associated with motor neuron death. Its differential action in CNS autoimmune diseases and neurodegenerative disorders, depending on the regimen used, allows its use as a therapy for either condition. Daily administration of Cop-1 is an approved treatment for multiple sclerosis. The protocol for non-autoimmune neurodegenerative diseases such as amyotrophic lateral sclerosis, remains to be established by future studies.
Aronica, E., D. Troost, et al. (2003). "Expression and regulation of voltage-gated sodium channel beta1 subunit protein in human gliosis-associated pathologies." Acta Neuropathol (Berl) 105(5): 515-23. Auxiliary beta1 subunits of voltage-gated sodium channels (NaChs) critically regulate channel activity and may also act as cell adhesion molecules (CAMs). In a recent study we have shown that the expression of beta1 NaCh protein is increased in reactive astrocytes in a rat epilepsy model of mesial temporal lobe epilepsy. The present study was undertaken to examine whether changes of NaCh beta1 subunit protein expression are also associated with structural changes occurring in human reactive astrocytes under different pathological conditions in vivo, as well as in response to changing environmental conditions in vitro. Strong beta1 astroglial immunoreactivity was present in human brain tissue from patients with astrogliosis. The over-expression of beta1 protein in reactive glia was observed in both epilepsy-associated brain pathologies (temporal lobe epilepsy, cortical dysplasia), as well as non-epileptic (cerebral infarction, multiple sclerosis, amyotrophic lateral sclerosis, meningo-encephalitis) disorders. The up-regulation of beta1 subunit protein in astrocytes can be reproduced in vitro. beta1 protein is highly expressed in human astrocytes cultured in the presence of trophic factors, under conditions in which they show morphology similar to the morphology of cells undergoing reactive gliosis. The growth factor-induced overexpression of beta1 protein was abrogated by PD98059, which inhibits the mitogen-activated protein kinase pathway. These findings demonstrate that the expression of NaCh beta1 subunit protein in astrocytes is plastic, and indicate a novel mechanism for modulation of glial function in gliosis-associated pathologies.
Beaulieu, J. M. and J. P. Julien (2003). "Peripherin-mediated death of motor neurons rescued by overexpression of neurofilament NF-H proteins." J Neurochem 85(1): 248-56. In previous studies, we showed that overexpression of peripherin, a neuronal intermediate filament (IF) protein, in mice deficient for neurofilament light (NF-L) subunits induced a progressive adult-onset degeneration of spinal motor neurons characterized by the presence of IF inclusion bodies reminiscent of axonal spheroids found in amyotrophic lateral sclerosis (ALS). In contrast, the overexpression of human neurofilament heavy (NF-H) proteins provoked the formation of massive perikaryal IF protein accumulations with no loss of motor neurons. To further investigate the toxic properties of IF protein inclusions, we generated NF-L null mice thatco-express both peripherin and NF-H transgenes. The axonal count in L5 ventral roots from 6 and 8-month-old transgenic mice showed that NF-H overexpression rescued the peripherin-mediated degeneration of motor neurons. Our analysis suggests that the protective effect of extra NF-H proteins is related to the sequestration of peripherin into the perikaryon of motor neurons, thereby abolishing the development of axonal IF inclusions that might block transport. These findings illustrate the importance of IF protein stoichiometry in formation, localization and toxicity of neuronal inclusion bodies.
Beaulieux, F., M. M. Berger, et al. (2003). "RNA extraction and RT-PCR procedures adapted for the detection of enterovirus sequences from frozen and paraffin-embedded formalin-fixed spinal cord samples." J Virol Methods 107(2): 115-20. Methods for detecting enterovirus RNA in both paraffin-embedded, formalin-fixed and frozen spinal cord sections from amyotrophic lateral sclerosis (ALS) patients were established. A proteinase K digestion following the deparaffinization procedure was required for the fixed spinal cord sections, whereas only one step of crushing in phosphate buffered saline was necessary for the frozen samples prior to the extraction of the RNA. With an optimized reverse transcription and PCR procedure, enterovirus RNA could be detected from frozen and fixed archival spinal cord samples.
Bolmsjo, I. and G. Hermern (2003). "Conflicts of interest: experiences of close relatives of patients suffering from amyotrophic lateral sclerosis." Nurs Ethics 10(2): 186-98. It is well known that close relatives of terminally ill patients endure great emotional stress. Many factors, such as existential concerns, contribute to the distress of these relatives. In this study, interviews were conducted to explore experiences concerning life restrictions, emotional distress, and limited support, in a group of close relatives of patients with amyotrophic lateral sclerosis (ALS). The purpose was to identify, illuminate and clarify ethical problems related to these experiences. The results indicate that close relatives of patients with ALS need someone to talk to, as well as more information about the disease and its process. Furthermore, the study illustrates how ethical problems are related to choices and conflicts, and that a process including shared decision making is often an ideal when trying to find a solution to ethical problems.
Campiani, G., C. Fattorusso, et al. (2003). "Neuronal High-Affinity Sodium-Dependent Glutamate Transporters (EAATs): Targets for the Development of Novel Therapeutics Against Neurodegenerative Diseases." Curr Pharm Des 9(8): 599-625. L-Glutamate is the major excitatory neurotransmitter in mammalian central nervous system, and excitatory amino acid transporters (EAATs) are essential for terminating synaptic excitation and for maintaining extracellular glutamate concentration below toxic levels. Although the structure of these channel-like proteins has not been yet reported, their membrane topology has been hypothesised based on biochemical and protein sequence analyses. In the case of an inadequate clearance from synaptic cleft and from the extrasynaptic space, glutamate behaves as a potent neurotoxin, and it may be related to several neurodegenerative pathologies including epilepsy, ischemia, amyotrophic lateral sclerosis, and Alzheimer disease. The recent boom of glutamate is demonstrated by the enormous amount of publications dealing with the function of glutamate, with its role on modulation of synaptic transmission throughout the brain, mainly focusing: i) on the structure of its receptors, ii) on molecular biology and pharmacology of Glu transporters, and iii) on the role of glutamate uptake and reversal uptake in several neuropathologies. This review will deal with the recent and most interesting published results on Glu transporters membrane topology, Glu transporters physiopathological role and Glu transporters medicinal chemistry, highlighting the guidelines for the development of potential neuroprotective agents targeting neuronal high-affinity sodium-dependent glutamate transporters.
Cid, C., J. C. Alvarez-Cermeno, et al. (2003). "Low concentrations of glutamate induce apoptosis in cultured neurons: implications for amyotrophic lateral sclerosis." J Neurol Sci 206(1): 91-5. Evidence is accumulating that excessive glutamate concentration in the extracellular space is neurotoxic and plays a role in amyotrophic lateral sclerosis (ALS). However, the published results on glutamate levels in cerebrospinal fluid (CSF) and on glutamate-mediated toxicity of CSF in ALS disease remain controversial. In this report, we studied CSF from patients with sporadic ALS and controls to determine glutamate concentrations, and then analyzed the neurotoxic effect of glutamate at the concentrations present in CSF from ALS patients on cultured cortical neuronal cells. Our study shows that glutamate, at the concentrations found in CSF from ALS patients (5.8 microM), diminished cell viability and increased apoptosis determined by the fluorescent DNA-binding dye Hoechst 33342 as well as by Terminal deoxynucleotidyl transferase (TdT)-mediated dUTP Nick End-Labeling (TUNEL) reaction in cultured neuronal cells. However, glutamate concentrations as those found in CSF from controls (2.8 microM or below) did not induce any effect. Both significant glutamate-induced effects were inhibited in the presence of NBQX (2,3-dihydroxy-6-nitro-7-sulfamoyl-benzo(f)quinoxaline-2,3-dione), an alpha-amino-3-hydroxy-5-methyl-4-isoxazole propionic acid (AMPA)/kainate-sensitive glutamate receptor antagonist. These results demonstrate that AMPA/kainate receptors are involved in the glutamate-mediated neurotoxic effects on cultured neurons, according to reports that implicate these receptors in ALS disease. We conclude that the glutamate-mediated neuronal apoptosis through AMPA/kainate receptors could occur in ALS patients who have elevated CSF glutamate concentration.
Conforti, L., C. Dell'Agnello, et al. (2003). "Kif1Bbeta isoform is enriched in motor neurons but does not change in a mouse model of amyotrophic lateral sclerosis." J Neurosci Res 71(5): 732-9. The kinesin superfamily motor protein Kif1B is expressed in two isoforms, Kif1Balpha and Kif1Bbeta, with distinct cargo-binding domains. We examined the mRNA distribution of the two isoforms in adjacent sections of brain and spinal cord of adult mice using in situ hybridization analysis. Kif1Bbeta mRNA is enriched in several regions of brain and spinal cord. Its levels are four to five times higher than that of the alpha isoform, which was barely detectable. The highest mRNA levels of Kif1Bbeta were found in the cortex, hippocampus, cerebellum and the grey matter of the spinal cord. At the cellular level the highest signal was found in motor neurons in the motor nuclei of medulla oblongata and the ventral horn of spinal cord. Because expression of other Kif genes is altered in amyotrophic lateral sclerosis (ALS) models, we examined the expression level of Kif1Bbeta mRNA in the spinal cord of transgenic mice carrying the SOD1G93A mutation, a model of familial ALS, at presymptomatic and early stages of the disease. No changes were observed in Kif1Bbeta mRNA in motor neurons or in other regions of the spinal cord. These findings indicate that Kif1Balpha, which modulates the transport of mitochondria, may play a major role in tissues other than the central nervous system. Instead Kif1Bbeta, responsible for the transport of synaptic vesicle precursors, seems to play an important role in the nervous system, particularly in the lower motor neurons. The absence of changes of Kif1Bbeta mRNA in transgenic SOD1G93A mice suggests that other molecular mechanisms may play a role in the disruption of axonal transport occurring in the motor neurons of these mice.
Copray, J. C., D. Jaarsma, et al. (2003). "Expression of the low affinity neurotrophin receptor p75 in spinal motoneurons in a transgenic mouse model for amyotrophic lateral sclerosis." Neuroscience 116(3): 685-94. Amyotrophic lateral sclerosis is a lethal neurodegenerative disorder involving motoneuron loss in the cortex, brainstem and spinal cord, resulting in progressive paralysis. Aberrant neurotrophin signalling via the low affinity neurotrophin receptor p75 has been suggested to be involved in the motoneuron death by the activation of apoptotic pathways. In order to investigate the involvement of neurotrophin receptor p75 in the amyotrophic lateral sclerosis related motoneuron degeneration process, we have studied the expression of this receptor in the spinal cord of transgenic mice carrying a mutated human Cu, Zn superoxide dismutase gene. Mutations in the superoxide dismutase gene are one of the genetic causes for familiar amyotrophic lateras sclerosis and human superoxide dismutase-1 transgenic mice develop symptoms and pathology similar to those in human amyotrophic lateras sclerosis. Our study shows that in these mice, spinal motoneurons, which normally do not contain the neurotrophin receptor p75 receptor, express this receptor during the progress of the disease. Expression of the neurotrophin receptor p75 receptor coincides with the expression of activating transcription factor 3, a member of the activating transcription factor/cyclic AMP family of stress transcription factors. Only a minority of these spinal motoneurons actually showed co-expression of neurotrophin receptor p75 with caspase-3 activity, suggesting that expression of the neurotrophin receptor p75 receptor is not directly related to the execution phase of the apoptosis process.
Corcia, P., P. Giraud, et al. (2003). "[Acute Motor axonal neuropathy, enterovirus and Amyotrophic lateral sclerosis: can there be a link?]." Rev Neurol (Paris) 159(1): 80-2. Amyotrophic lateral sclerosis (ALS) is a neurodegenerative disorder of both upper and lower motor neurons. Acute motor axonal neuropathy (AMAN) affects only the lower motor neuron and occurs, in the majority of cases, after an infection. To date, the etiology of ALS remains unknown but seems multifactorial. A 60 year-old man with a past medical history of AMAN developed ALS 9 years later. At that time, genomic sequences of enterovirus (echovirus 6 and 7) were detected in cerebrospinal fluid by RT-PCR. This particular succession led to discuss a possible link between theses two disorders and consequently the involvement of enterovirus in the development of ALS.
del Aguila, M. A., W. T. Longstreth, Jr., et al. (2003). "Prognosis in amyotrophic lateral sclerosis: a population-based study." Neurology 60(5): 813-9. BACKGROUND: Accurate information on prognosis of ALS is useful to patients, families, and clinicians. METHODS: In a population-based study of ALS in western Washington, the authors assembled a cohort of 180 patients with incident ALS between 1990 and 1994. Information on potential prognostic factors was collected during an in-person interview. Patients also completed the Medical Outcomes Study Short Form 36 (SF-36). Vital status through December 1999 was known for all patients. RESULTS: Median survival was 32 months from onset of symptoms and 19 months from diagnosis. The 5-year survival after diagnosis was 7%. Older age and female sex were strongly associated with poor survival. In multivariable Cox proportional hazards regression models, factors significantly and independently associated with a worse prognosis included older age, any bulbar features at onset, shorter time from symptom onset to diagnosis, lack of a marital partner, and residence in King County. Recursive partitioning identified age, time from symptom onset to diagnosis, and marital status as the strongest predictors of survival. Good summary scores for physical health on the SF-36, but not for mental health, were significantly associated with longer survival than poor scores. CONCLUSION: These findings are consistent with other population-based studies of ALS and confirm its pernicious nature. Older age, female sex, any bulbar features at onset, short time from symptom onset to diagnosis, lack of a marital partner, and disease severity are key prognostic factors. Serial measurement of severity would likely improve predictions.
Dib, M. (2003). "Amyotrophic lateral sclerosis: progress and prospects for treatment." Drugs 63(3): 289-310. Fifteen years ago, a role for excitotoxic damage in the pathology of amyotrophic lateral sclerosis (ALS) was postulated. This stimulated the development of riluzole, the only available treatment for the disease. Since then, the identification of abnormal forms of superoxide dismutase as the genetic basis of certain familial forms of ALS has provided a huge impetus to the search for new effective treatments for this devastating disease. Transgenic mouse models have been developed expressing these aberrant mutants that develop a form of motor neurone disease the progress of which can be slowed by riluzole. Studies in these mice have provided evidence for a role for excitotoxic, apoptotic and oxidative processes in the development of pathology. The mice can be used for testing molecules targeting these processes as potential therapies, to allow the most promising to be evaluated in humans. Several such agents are currently in clinical trials. Many previous clinical trials in ALS were insufficiently powered to demonstrate any relevant effect on disease progression. This situation has been to some extent remedied in the more recent trials, which have recruited many hundreds of patients. However, with the exception of studies with riluzole, the results of these have been disappointing. In particular, a number of large trials with neurotrophic agents have revealed no evidence for efficacy. Nonetheless, the need for large multinational trials of long duration limits the number that can be carried out and makes important demands on investment. For this reason, surrogate markers that can be used for rapid screening in patients of potential treatments identified in the transgenic mice are urgently needed.
Dunlop, J., H. Beal McIlvain, et al. (2003). "Impaired spinal cord glutamate transport capacity and reduced sensitivity to riluzole in a transgenic superoxide dismutase mutant rat model of amyotrophic lateral sclerosis." J Neurosci 23(5): 1688-96. We characterized synaptosomal glutamate transport activity in a recently developed transgenic rat model of amyotrophic lateral sclerosis (ALS) overexpressing the G93A Cu(2+)/Zn(2+) superoxide dismutase (SOD1) mutation. Using spinal cord synaptosomes, a significant reduction (43%) in the maximal velocity for high-affinity, Na(+)-dependent glutamate uptake was observed at disease end stage in G93A rats compared with age-matched controls. Similarly, a 27% reduction in maximum velocity (V(max)) was measured at disease onset, but no difference in spinal cord V(max) values were observed with presymptomatic animals compared with controls. In comparison, we observed no differences in the V(max) for glutamate clearance at disease end stage with synaptosomes from cortex, hippocampus, striatum, cerebellum, and brainstem, indicating a specific deficit in the spinal cord. The pharmacological sensitivity of spinal cord uptake to dihydrokainate suggests that the GLT-1 (glutamate transporter-1) subtype primarily mediates the transport activity. Expression analysis revealed a loss of GLT-1 as well as qualitative changes in GLAST (glutamate/aspartate transporter) but no measurable changes in EAAC1 (excitatory amino acid carrier 1) in spinal cord of end-stage G93A rats, indicating that deficits in glutamate transporters in this rat model may be glial specific. Riluzole, a neuroprotective agent used clinically to slow the progression of ALS, produced an enhancement of spinal cord synaptosomal glutamate uptake in control animals and early-stage disease G93A rats, but this effect was lost in end-stage animals. Altered expression of astroglial glutamate transporters accompanied by reduced capacity for spinal cord clearance of extracellular glutamate in the G93A SOD1 transgenic rat may account for a dampened effect of riluzole to enhance glutamate uptake at end-stage disease.
Duque, P., M. D. Paramo, et al. (2003). "[Neuropsychological disorders in amyotrophic lateral sclerosis. Don t they exist or do they just go undetected?]." Rev Neurol 36: 3-8. AIMS. The aims of this paper is to demonstrate the existence of neuropsychological disorders in amyotrophic lateral sclerosis (ALS) and to perform an in depth study of the cognitive functioning of the prefrontal lobes. PATIENTS AND METHODS. A neuropsychological study of 14 patients with ALS was conducted using an extensive battery of tests and were compared with a group of 14 healthy controls. Both groups were homogeneous as regards age, sex, education and manual dominance. In this clinical and research study, as well as the neuropsychological variables (subtest of the Barcelona PIEN Test neuropsychological battery), we also took the evolution of the disease, the age and neurological clinical features of the patients suffering from ALS into account. RESULTS. We found neuropsychological disorders in the ALS patients that were centred, either directly or indirectly, on functions of the prefrontal lobe, and in particular of the dorsolateral and premotor cortices, which had already been observed in other research work. No memory disorders were found, something which is usually mentioned in studies about neuropsychological disorders in this type of patients. CONCLUSIONS. Apart from the primary motor zones affected in ALS, there appears to be a degenerative process in most of the frontal lobe, and there is a need for longitudinal studies of the possible progressive disorders of the frontal lobe in these patients. This is difficult, since these patients end up with serious neurological alterations which prevent a correct neuropsychological exploration from being carried out cognitively, and hence no conclusions can be drawn either
Egana, J. T., C. Zambrano, et al. (2003). "Iron-induced oxidative stress modify tau phosphorylation patterns in hippocampal cell cultures." Biometals 16(1): 215-23. Oxidative stress phenomena have been related with the onset of neurodegenerative diseases. Particularly in Alzheimer Disease (AD), oxygen reactive species (ROS) and its derivatives can be found in brain samples of postmortem AD patients. However, the mechanisms by which oxygen reactive species can alter neuronal function are still not elucidated. There is a growing amount of evidence pointing to a role for mitochondrial damage as the source of free radicals involved in oxidative stress. Among the species that participate in the production of oxygen reactive radicals, transition metals are one of the most important. Several reports have implicated the involvement of redox-active metals with the onset of different neurodegenerative diseases such as Alzheimer's Disease (AD), Progressive Supranuclear Palsy (PSP), Amyotrophic Lateral Sclerosis (ALS) and Parkinson's Disease (PD). On the other hand, our previous studies have indicated that A beta-induced deregulation of the protein kinase Cdk5 associated with tau protein hyperphosphorylation constitute a critical pathway toward neurodegeneration. In the current paper we have shown that iron induces an imbalance in the function of Cdk5/p25 system of hippocampal neurons, resulting in a marked decrease in tau phosphorylation at the typical Alzheimer's epitopes. The loss of phosphorylated tau epitopes correlated with an increase in 4-hydroxy-nonenal (HNE) adducts revealing damage by oxidative stress. This effects on tau phosphorylation patterns seems to be a consequence of a decrease in the Cdk5/p25 complex activity that appears to result from a depletion of the activator p25, a mechanism in which calcium transients could be implicated.
Elam, J. S., K. Malek, et al. (2003). "An alternative mechanism of bicarbonate-mediated peroxidation by copper-zinc superoxide dismutase." J Biol Chem. Hydrogen peroxide can interact with the active site of copper-zinc superoxide dismutase (SOD1) to generate a powerful oxidant. This oxidant can either damage amino acid residues at the active site, inactivating the enzyme (the self-oxidative pathway), or oxidize substrates exogenous to the active site, preventing inactivation (the external oxidative pathway). It is well-established that the presence of bicarbonate anion dramatically enhances the rate of oxidation of exogenous substrates. Here, we show that bicarbonate also substantially enhances the rate of self-inactivation of human wild type SOD1. Together, these observations suggest that the strong oxidant formed by hydrogen peroxide and SOD1 in the presence of bicarbonate arises from a pathway that is mechanistically distinct from that producing the oxidant in its absence. Self-inactivation rates are further enhanced in a mutant SOD1 protein (L38V) linked to the fatal neurodegenerative disorder familial amyotrophic lateral sclerosis (FALS). The 1.4 resolution crystal structure of pathogenic SOD1 mutant D125H reveals the mode of oxyanion binding in the active site channel and implies that phosphate anion attenuates the bicarbonate effect by competing for binding to this site. The orientation of the enzyme-associated oxyanion suggests that both the self- and external oxidative pathways can proceed through an enzyme-associated peroxycarbonate intermediate. As the concentration of bicarbonate in biological fluids is significant (~25 mM), the outcomes of peroxycarbonate-mediated activities by SOD1 have implications for understanding oxidative cellular damage and FALS etiology.
Ellis, D. Z., J. Rabe, et al. (2003). "Global loss of Na,K-ATPase and its nitric oxide-mediated regulation in a transgenic mouse model of amyotrophic lateral sclerosis." J Neurosci 23(1): 43-51. Na,K-ATPase plays a critical role in energy metabolism and ion fluxes. Its loss was investigated in the G93A mouse model of amyotrophic lateral sclerosis (ALS) in which the mutation of Cu/Zn superoxide dismutase (SOD1) is thought to lead to aberrant oxidative damage. Observed losses in spinal cord Na,K-ATPase activity exceeded all expectations. All three catalytic subunit isoforms (alpha1, alpha2, alpha3) were reduced, and the global alpha subunit loss affected not just neurons, glia, and myelinated axon tracts but even ependymal and pial membranes. Decreases in Na,K-ATPase activity were greater than losses of protein, and there were losses of Na,K-ATPase alpha, but not beta, subunits. Together, these observations are consistent with selective degradation of the alpha subunit after damage. Overexpression of normal SOD1 does not cause ALS-like symptoms, but it has other known pathological effects. In transgenic mice overexpressed normal human SOD1 had a smaller but still considerable effect on Na,K-ATPase. Furthermore, the nitric oxide-mediated regulatory pathway for Na,K-ATPase inhibition was undetectable in spinal cord tissue slices from mice overexpressing either mutant or normal human SOD1. Na,K-ATPase activity did not respond to nitric oxide donors, and the free radical-dependent step of the pathway could not be bypassed by the addition of the downstream protein kinase G activator, 8-Br-cGMP. The data demonstrate that Na,K-ATPase is vulnerable to aberrant SOD1 activity, making it a potential contributing factor in disease pathology. Moreover, the global cellular distribution of Na,K-ATPase loss indicates that SOD1 overexpression is far-reaching in its pathological effects.
Farah, C. A., M. D. Nguyen, et al. (2003). "Altered levels and distribution of microtubule-associated proteins before disease onset in a mouse model of amyotrophic lateral sclerosis." J Neurochem 84(1): 77-86. Alterations of the axonal transport and microtubule network are potential causes of motor neurodegeneration in mice expressing a mutant form of the superoxide dismutase 1 (SOD1G37R) linked to amyotrophic lateral sclerosis (ALS). In the present study, we investigated the biology of microtubule-associated proteins (MAPs), responsible for the formation and stabilization of microtubules, in SOD1G37R mice. Our results show that the protein levels of MAP2, MAP1A, tau 100 kDa and tau 68 kDa species decrease significantly as early as 5 months before onset of symptoms in the spinal cord of SOD1G37R mice, whereas decrease in levels of tau 52-55 kDa species is most often noted with the manifestation of the clinical symptoms. Interestingly, there was no change in the protein levels of MAPs in the brain of SOD1G37R mice, a CNS organ spared by the mutant SOD1 toxicity. Remarkably, as early as 5 months before disease onset, the binding affinities of MAP1A, MAP2 and tau isoforms to the cytoskeleton decreased in spinal cord of SOD1G37R mice. This change correlated with a hyperphosphorylation of the soluble tau 52-55 kDa species at epitopes recognized by the antibodies AT8 and PHF-1. Finally, a shift in the distribution of MAP2 from the cytosol to the membrane is detected in SOD1G37R mice at the same stage. Thus, alterations in the integrity of microtubules are early events of the neurodegenerative processes in SOD1G37R mice.
Friedlander, R. M. (2003). "Apoptosis and caspases in neurodegenerative diseases." N Engl J Med 348(14): 1365-75.
Gajewski, C. D., M. T. Lin, et al. (2003). "Mitochondrial DNA from platelets of sporadic ALS patients restores normal respiratory functions in rho(0) cells." Exp Neurol 179(2): 229-35. Amyotrophic lateral sclerosis (ALS) is a devastating neurodegenerative disease, which affects the anterior horn cells of the spinal cord and cortical motor neurons. A pathophysiological role for mtDNA mutations was postulated based on the finding that cybrids obtained from mitochondria of sporadic ALS patients exhibited impaired respiratory chain activities, increased free radical scavenging enzymes, and altered calcium homeostasis. To date, however, no distinct mtDNA alterations associated with ALS have been reported. Therefore, we reexamined the hypotheses that mtDNA mutations accumulate in ALS and that cybrids generated from ALS patients' blood have impaired mitochondrial respiration. Cybrid cell lines were generated from 143B osteosarcoma rho(0) cells and platelet mitochondria of sporadic ALS patients or age-matched controls. We found no statistically significant differences in mitochondrial respiration between ALS and control cybrids, even when the electron transport chain was stressed with low concentrations of respiratory chain inhibitors. Mitochondrial respiratory chain enzyme activities were also normal in ALS cybrids, and there was no increase in free radical production. Therefore, we showed that mtDNA from platelets of ALS patients was able to restore normal respiratory function in rho(0) cells, suggesting that the presence of mtDNA mutations capable of affecting mitochondrial respiration was unlikely.
Gourie-Devi, M. and A. Nalini (2003). "Long-term follow-up of 44 patients with brachial monomelic amyotrophy." Acta Neurol Scand 107(3): 215-20. OBJECTIVES -: Monomelic amyotrophy of a single upper limb termed "brachial monomelic amyotrophy" (BMMA) is a benign lower motor neuron disorder in the young, with male preponderance, insidious onset of atrophy and weakness, electromyographic evidence of neurogenic pattern without conduction block, slow progression for 2-4 years followed by a stationary course. The aim of the study was to determine whether (i) atrophy and weakness in the affected limb progresses beyond 5 years; (ii) the illness spreads to the other limbs; and (iii) the disease progresses to amyotrophic lateral sclerosis. MATERIAL AND METHODS -: Forty-four patients who had a duration of illness of 5 years or more at the last follow-up examination were included in the study. Assessment of symptom profile, neurologic deficit and disability was performed at variable intervals during the follow-up period. RESULTS -: Progression of the disease was seen in 37 (84.1%) patients, up to 5 years in 35 (79.5%), 6 years in one and 8 years in another patient. In seven patients (15.9%) the atrophy was accidentally noticed and no further change in the neurologic deficit was observed thereafter. Subsequent to attaining a stationary course, none of the 44 subjects developed fresh symptoms or signs during a mean follow-up period of 9.7 years (range 2.5-23). The mean duration of illness at last follow-up was 12.8 years (range 5-26.5) and in 22 (50%) subjects the disease duration was more than 10 years. Seven patients (15.9%) at presentation had minimal involvement of contralateral upper limb with gross asymmetry and later one more patient developed similar features. Thus, in only a small proportion (18.2%) of patients the neurologic deficit had extended beyond the confines of one upper limb. None of the patients developed involvement of cranial nerves, lower limbs or pyramidal signs. CONCLUSIONS -: Progression of the neurologic deficit in the affected limb was seen up to 5 years in the majority followed by a stationary phase with no evidence of fresh neurologic deficit during the follow-up period. Spread to the contralateral upper limb with minimal neurologic deficit was seen in less than a fifth of the patients, but involvement of lower limbs was not observed. BMMA did not evolve to amyotrophic lateral sclerosis. These observations underscore the benign and self limiting course of BMMA.
Guegan, C. and S. Przedborski (2003). "Programmed cell death in amyotrophic lateral sclerosis." J Clin Invest 111(2): 153-61.
Hedberg, K., D. Hopkins, et al. (2003). "Five years of legal physician-assisted suicide in Oregon." N Engl J Med 348(10): 961-4.
Henderson, R. D., R. McClelland, et al. (2003). "Effect of changing data collection parameters on statistical motor unit number estimates." Muscle Nerve 27(3): 320-31. The effect of number of samples and selection of data for analysis on the calculation of surface motor unit potential (SMUP) size in the statistical method of motor unit number estimates (MUNE) was determined in 10 normal subjects and 10 with amyotrophic lateral sclerosis (ALS). We recorded 500 sequential compound muscle action potentials (CMAPs) at three different stable stimulus intensities (10-50% of maximal CMAP). Estimated mean SMUP sizes were calculated using Poisson statistical assumptions from the variance of 500 sequential CMAP obtained at each stimulus intensity. The results with the 500 data points were compared with smaller subsets from the same data set. The results using a range of 50-80% of the 500 data points were compared with the full 500. The effect of restricting analysis to data between 5-20% of the CMAP and to standard deviation limits was also assessed. No differences in mean SMUP size were found with stimulus intensity or use of different ranges of data. Consistency was improved with a greater sample number. Data within 5% of CMAP size gave both increased consistency and reduced mean SMUP size in many subjects, but excluded valid responses present at that stimulus intensity. These changes were more prominent in ALS patients in whom the presence of isolated SMUP responses was a striking difference from normal subjects. Noise, spurious data, and large SMUP limited the Poisson assumptions. When these factors are considered, consistent statistical MUNE can be calculated from a continuous sequence of data points. A 2 to 2.5 SD or 10% window are reasonable methods of limiting data for analysis.
Hu, J. H., H. Zhang, et al. (2003). "Protein kinase and protein phosphatase expression in amyotrophic lateral sclerosis spinal cord." J Neurochem 85(2): 432-42. The Kinetworks trade mark multi-immunoblotting technique was used to evaluate the expressions of 78 protein kinases, 24 protein phosphatases and phosphorylation states of 31 phosphoproteins in thoracic spinal cord tissue from control subjects and patients having the sporadic form of amyotrophic lateral sclerosis (ALS). In both the cytosolic (C) and particulate (P) fractions of spinal cord from ALS patients as compared with controls, there were increased levels of calcium/calmodulin-dependent protein kinase kinase (CaMKK; C = 120% increase/P = 580% increase;% change, compared with control), extracellular regulated kinase 2 (ERK2; C = 120% increase/P = 170% increase), G protein-coupled receptor kinase 2 (GRK2; C = 140% increase/P = 140% increase), phospho-Y279/216 glycogen synthase kinase 3 alpha/beta (GSK3alpha/beta; C = 90% increase/P = 220% increase), protein kinase B alpha (PKBalpha; C = 360% increase/P = 200% increase), phospho-T638 PKCalpha/beta (C = 630% increase/P = 170% increase), cGMP-dependent protein kinase (PKG; C = 100% increase/P = 75% increase), phospho-T451 dsRNA-dependent protein kinase (PKR; C = 2600% increase/P = 3330% increase), ribosomal S6 kinase 1 (RSK1; C = 750% increase/P = 630% increase), phospho-T389 p70 S6 kinase (S6K; C = 1000% increase/P = 460% increase), and protein-tyrosine phosphatase 1 delta (PTP1delta; C = 43% increase/P = 70% increase). Cytosolic increases in phospho-alpha-S724/gamma-S662 adducin (C = 15650% increase), PKCalpha (C = 100% increase) and PKCzeta (C = 190% increase) were found in ALS patients as compared with controls, while particulate increases in cAMP-dependent protein kinase (PKA; 43% increase), protein kinase C beta (PKCbeta; 330% increase), and stress-activated protein kinase beta (SAPKbeta; 34% increase) were also observed. Cyclin-dependent kinase-associated phosphatase (KAP) was apparently translocated, as it was reduced (31% decrease) in cytosolic fractions but elevated (100% increase) in particulate fractions of ALS spinal cord tissue. Our observations indicate that ALS is associated with the elevated expression and/or activation of many protein kinases, including PKCalpha, PKCbeta, PKCzeta and GSK3alpha/beta, which may augment neural death in ALS, and CaMKK, PKBalpha, Rsk1, S6K, and SAPK, which may be a response to neuronal injury that potentially can mitigate cell death.
Hu, J. H., K. Chernoff, et al. (2003). "Protein kinase and protein phosphatase expression in the central nervous system of G93A mSOD over-expressing mice." J Neurochem 85(2): 422-31. The expressions of 78 protein kinases, 24 protein phosphatases and 31 phosphoproteins were investigated by Kinetworks trade mark analysis in brain and spinal cord tissue of transgenic mice over-expressing G93A mutant superoxide dismutase (mSOD), a murine model of amyotrophic lateral sclerosis (ALS). In the brains of affected mSOD mice, we observed increased expression of cAMP-dependent protein kinase (PKA, 111% increase compared with control), and protein phosphatase 2B Aalpha-catalytic subunit (calcineurin, 109% increase), and reductions in the levels of PAK3 (76% decrease) and protein phosphatase 2C Cbeta-subunit (32% decrease). Increased Ser259 phosphorylation of Raf1 (126% increase) in mSOD mice correlated with higher expression of p73 Raf1 (147% increase). There was also increased p73 Raf1 (69% increase) and Ser259 phosphorylation (45% increase) in the spinal cords of mSOD mice. While adducin underwent enhanced phosphorylation (alphaS724, 90% increase; gammaS662, 290% increase) in mSOD brain, its phosphorylation was lower in the mSOD spinal cord (alphaS724, 53% decrease; gammaS662, 46% decrease). In spinal cords of affected mSOD mice, we also observed elevated expression of casein kinase 1delta (CK1delta, 157% increase), JAK2 (84% increase), PKA (183% increase), protein kinase C (PKC) delta (123% increase), p124 PKC micro (142% increase), and RhoA kinase (221% increase), and enhanced phosphorylation of extracellular regulated kinases 1 (ERK1, T202/Y204, 90% increase), and 2 (ERK2, T185/Y187, 73% increase), p38 MAP kinase (T180/Y182, 1570% increase), and PKBalpha (T308, 154% increase; S473, 61% increase). There was also reduced phosphorylation of RB (S780, 45% decrease; S807/S811, 65% decrease), Src (Y418, 63% decrease) and p40 SAPK/JNKbeta (T183/Y185, 43% decrease). Variability in the expression of kinases, phosphatases and phosphorylation of their substrates was observed even in mutant animals having a similar phenotype. The expression and phosphorylation differences between mSOD and control mice were dissimilar to those between ALS patients and controls. This finding indicates that the activation of protein kinases and phosphoproteins is different with neuron loss in the mSOD mouse compared with that seen in patients with the sporadic form of ALS.
Ischiropoulos, H. and J. S. Beckman (2003). "Oxidative stress and nitration in neurodegeneration: cause, effect, or association?" J Clin Invest 111(2): 163-9.
Ishihara, K., H. Murakami, et al. (2003). "[A case of amyotrophic lateral sclerosis with dementia presenting long clinical course]." No To Shinkei 55(2): 157-61. We describe a patient with amyotrophic lateral sclerosis with dementia (ALS-D) displaying a long clinical course. A 68-year-old Japanese male with no family history of note was admitted complaining of severe dysarthria and dysphagia. At 63 years old, Pick's disease was diagnosed on the basis of abnormal behavior, such as "Denkfaulheit" and moria, and temporal lobe atrophy observed on magnetic resonance imaging (MRI). Five years after onset, dysarthria and dysphagia emerged, and gradually worsened. On admission, muscular weakness of the upper extremities, fasciculation, and exaggerated tendon stretch reflexes were noted. Needle electromyography performed on the left upper and lower extremities revealed neurogenic pattern changes. Based on these findings and clinical course, ALS-D was diagnosed. Due to severe bulbar palsy, verbal communication was impossible. However, neither specific symptoms of dementia nor abnormal behavior was demonstrated, although this latter had been observed 5 years ago, with only short-term memory impairment apparent. MRI disclosed severe knife-edge atrophy of bilateral temporal lobes, most prominently in the anterior regions. SPECT images revealed decreased uptake of tracer in bilateral inferior temporal lobes, predominantly on the left side. The patient died suddenly 4 months after admission, and post-mortem examination was not conducted. Total clinical course was about 8 years. Several cases of ALS-D have displayed similar clinical courses to the presented case. Some of these would also have initially been diagnosed as Pick's disease. We speculate that cases displaying psychiatric symptoms for several years and initially diagnosed as Pick's disease may finally be diagnosed as ALS-D upon the eventual emergence of motor symptoms(bulbar palsy).
Jan Groeneveld, G., J. H. Veldink, et al. (2003). "A randomized sequential trial of creatine in amyotrophic lateral sclerosis." Ann Neurol 53(4): 437-45. Amyotrophic lateral sclerosis (ALS) is a fatal disease with no cure. In a transgenic mouse model of ALS, creatine monohydrate showed a promising increase in survival. We performed a double-blind, placebo-controlled, sequential clinical trial to assess the effect of creatine monohydrate on survival and disease progression in patients with ALS. Between June 2000 and December 2001, 175 patients with probable, probable-laboratory supported, or definite ALS were randomly assigned to receive either creatine monohydrate or placebo 10gm daily. A sequential trial design was used with death, persistent assisted ventilation, or tracheostomy as primary end points. Secondary outcome measurements were rate of decline of isometric arm muscle strength, forced vital capacity, functional status, and quality of life. The trial was stopped when the null hypothesis of indifference was accepted. Creatine did not affect survival (cumulative survival probability of 0.70 in the creatine group vs 0.68 in the placebo group at 12 months, and 0.52 in the creatine group vs 0.47 in the placebo group at 16 months), or the rate of decline of functional measurements. Creatine intake did not cause important adverse reactions. This placebo-controlled trial did not find evidence of a beneficial effect of creatine monohydrate on survival or disease progression in patients with ALS. Ann Neurol 2003;53:437-445
Jenkinson, C., J. M. Norquist, et al. (2003). "Deriving summary indices of health status from the Amyotrophic Lateral Sclerosis Assessment Questionnaires (ALSAQ-40 and ALSAQ-5)." J Neurol Neurosurg Psychiatry 74(2): 242-5. OBJECTIVES: To use statistical procedures, operationalising what is known as item response theory (IRT), to assess the unidimensionality of the 40 item Amyotrophic Lateral Sclerosis Assessment Questionnaire, and consequently to develop a single index figure from the measure. A secondary objective is to compare scores gained on the ALSAQ-40 with a five item short form (the ALSAQ-5). METHODS: Postal survey of patients diagnosed with motor neurone disease (MND) on the MND Associations database. Copies of the ALSAQ-40 and, nested within it, the ALSAQ-5 were completed on two occasions. At time one, the survey contained the ALSAQ-40 and demographic questions. In addition, patients were asked to indicate if they were willing to take part in the follow up. Those who agreed to do so were sent another copy of the questionnaire after a period of three months. Respondents were also asked to indicate how much change they had experienced since baseline on each of the five domains of the questionnaire. Rasch analysis, a form of IRT methodology, was used to determine if the 40 items in the ALSAQ-40 tapped an underlying "latent trait", and were consequently measuring a unidimensional construct. The results from the ALSAQ-40 single index were then compared with those gained from the ALSAQ-5. RESULTS: Analyses indicated that, at both baseline and follow up, all items on the ALSAQ-40 fitted the Rasch model. Consequently the 40 items were summed to create a single index. Results on this instrument were compared with those gained by summing the five items of the ALSAQ-5. Results on the instruments were found to be highly correlated. CONCLUSIONS: Evidence from the analyses suggests that 40 item ALSAQ does contain a unidimensional scale, and can, therefore be summed to create a single index. Furthermore the ALSAQ-5 closely replicates the results of the patient measure.
Kalra, S., N. R. Cashman, et al. (2003). "Gabapentin therapy for amyotrophic lateral sclerosis: lack of improvement in neuronal integrity shown by MR spectroscopy." AJNR Am J Neuroradiol 24(3): 476-80. BACKGROUND AND PURPOSE: Proton MR spectroscopy has revealed impaired neuronal integrity in the motor cortex of patients with amyotrophic lateral sclerosis (ALS). We hypothesized that the N-acetylaspartate (NAA)-creatine (Cr) ratios in the motor cortex and adjacent brain could reflect the therapeutic effectiveness of gabapentin (GBP) treatment in ALS. METHODS: Eight patients with ALS underwent MR spectroscopy before and 26.5 days +/- 8.8 after starting GBP. In 10 patients with ALS who were not treated with GBP, paired spectra were obtained 21.4 days +/- 7.2 apart. Fourteen healthy subjects underwent a single MR spectroscopic examination. The NAA/Cr ratio was measured in the precentral gyrus, the postcentral gyrus, the superior parietal lobule, the supplementary motor area, and the premotor cortex. RESULTS: The NAA/Cr ratio was decreased in the precentral and postcentral gyri of patients with ALS compared with healthy controls. In those with ALS, the change in the NAA/Cr ratio was not different between treated patients and untreated patients in any of the regions studied. CONCLUSION: No improvement in neuronal integrity was detected in motor and nonmotor cerebral regions after GBP treatment. This result agrees with that of prior investigations showing the equivocal clinical effectiveness of GBP for ALS and supports the validity of the NAA/Cr ratio as a surrogate of therapeutic effectiveness.
Kanai, K., S. Kuwabara, et al. (2003). "Muscle cramp in Machado-Joseph disease: Altered motor axonal excitability properties and mexiletine treatment." Brain 126(Pt 4): 965-73. Machado-Joseph disease is one of the most common hereditary spinocerebellar degenerative disorders with a wide range of clinical manifestations. Pathology studies have shown mild to moderate loss of anterior horn cells and, in terms of spinal pathology, Machado-Joseph disease is regarded as a type of lower motoneuron disease. Muscle cramps are often associated with lower motoneuron disorders, but features of cramps in Machado-Joseph disease patients have never been studied. We investigated the incidence and nature of muscle cramps in Machado-Joseph disease patients, the excitability properties of motor axons [strength-duration time constant (tau(SD)), threshold electrotonus, refractoriness and supernormality] using threshold tracking and the effects of mexiletine hydrochloride on those cramps. Of 20 consecutive patients, 16 (80%) had frequent, severe muscle cramps in the legs, trunk or arms that disturbed their daily activities. The frequency of pathological muscle cramps was similar to that for patients with amyotrophic lateral sclerosis (68%) and higher than those for patients with spinal muscular atrophy (33%) or peripheral axonal neurophathy (24%). Threshold-tracking studies showed that tau(SD), which in part reflects Na(+) conductance at the resting membrane potential, was significantly greater in the Machado-Joseph disease patients than in normal subjects; severe muscle cramps were associated with a longer tau(SD). Threshold electrotonus, refractoriness and supernormality were not significantly different between Machado-Joseph disease patients and normal subjects. Eight Machado-Joseph disease patients with severe cramps, who received mexiletine treatment, experienced nearly complete relief with a partial normalization of tau(SD) (P = 0.08). Muscle cramps are a very frequent and disabling factor in Machado-Joseph disease. Pathological muscle cramps responded well to mexiletine treatment, and this is consistent with the hypothesis that they are caused by an increase in persistent Na(+) conductance, possibly associated with axonal regeneration or collateral sprouting.
Kawai, S., M. Tsukuda, et al. (2003). "A study of the early stage of Dysphagia in amyotrophic lateral sclerosis." Dysphagia 18(1): 1-8. In amyotrophic lateral sclerosis (ALS) patients, dysphagia eventually occurs independent of time of onset. We studied dysphagia conditions in the early stage of ALS, principally at the oral phase. Videofluoroscopic and manometric studies were conducted on 11 patients (5 males and 6 females, age range = 47-82 years) who were diagnosed at our Neurology Clinic as having ALS. All patients were able to ingest orally. Swallowing scores on the ALS severity scale were from 10 to 5. In the oral phase of swallowing, abnormal movements of the anterior and/or posterior tongue were recognized in 8 cases. Dysphagia severity tended to be particularly influenced by dysfunction of the posterior tongue. Manometric studies were almost normal in all cases except one. These results suggested that the early stage of dysphagia in ALS was mainly caused by oral dysfunction, and the oral phase disorders began in some cases with a decreased function of bolus transport at the anterior part of the tongue, and in other cases with a deteriorated function of holding the bolus at the posterior part of the tongue. In conclusion, the tongue function of holding the bolus in the oral cavity mainly affects the severity of the early stage of dysphagia in ALS.
Khan, T. S. and R. A. Prayson (2003). "Pathologic quiz case: a 50-year-old man with progressive worsening of neurological symptoms." Arch Pathol Lab Med 127(2): E113-4.
Kikuchi, H., T. Yamada, et al. (2003). "Involvement of cathepsin B in the motor neuron degeneration of amyotrophic lateral sclerosis." Acta Neuropathol (Berl) 105(5): 462-8. Abnormal proteolysis may be involved in the motor neuron degeneration of amyotrophic lateral sclerosis (ALS). Although several studies of the ubiquitin-proteasome system in ALS have been reported, the endosome-lysosome system has not been investigated in detail. To clarify the association of neurodegeneration with the endosome-lysosome system in ALS, we examined the pathological expression of cysteine proteases such as cathepsins B, H and L and an aspartate protease, cathepsin D, in the anterior horns of 15 ALS cases and 5 controls. In the ALS cases, cathepsin B immunoreactivity was preferentially decreased in the lateral parts of the anterior gray horns compared with the controls. Its immunoreactivity was increased in the cytoplasm of both shrunken and pigmented neurons but was weak in the neurons containing Bunina bodies. In addition, reactive astrocytes were also immunolabeled with cathepsin B. Cathepsin H and cathepsin L were detected in the cytoplasm of a small number of shrunken and pigmented neurons. Cathepsin D immunoreactivity was strong in the cytoplasm of all motor neurons. The immunoreactivity of cathepsins H, L and D was not significantly different between control and ALS cases. Western blot analysis showed that the 25-kDa activated form of cathepsin B was down-regulated in ALS. Our results suggest that cathepsin B is involved in the motor neuron degeneration in ALS.
Kikuchi, S., K. Shinpo, et al. (2003). "Glycation-a sweet tempter for neuronal death." Brain Res Brain Res Rev 41(2-3): 306-23. Glycation, one of the post-translational modifications of proteins, is a nonenzymatic reaction initiated by the primary addition of a sugar aldehyde or ketone to the amino groups of proteins. In the early stage of glycation, the synthesis of intermediates leading to the formation of Amadori compounds occurs. In the late stage, advanced glycation end products (AGE) are irreversibly formed after a complex cascade of reactions. Several AGEs have been characterized chemically, while other new compounds remain to be identified. To date, studies of the contribution of glycation to diseases have been primarily focused on its relationship to diabetes and diabetes-related complications. However, glucose-induced damage is not limited to diabetic patients. Although it does not cause rapid or remarkable cell damage, glycation advances slowly and accompanies every fundamental process of cellular metabolism. It has recently become clear that glycation also affects physiological aging and neurodegenerative diseases such as Alzheimer's disease and amyotrophic lateral sclerosis. Glycation alters the biological activity of proteins and their degradation processes. Protein cross-linking by AGE results in the formation of detergent-insoluble and protease-resistant aggregates. Such aggregates may interfere with both axonal transport and intracellular protein traffic in neurons. In addition, glycation reactions lead to the production of reactive oxygen species. Conversely, glycation is promoted by oxidative stress. We speculate on the presence of synergism between glycation and oxidative stress. In this review, we provide an outline of glycation and propose some possible mechanisms of its cytotoxicity and defense systems against it.
Kikuchi, S., K. Shinpo, et al. (2003). "Brefeldin A-induced neurotoxicity in cultured spinal cord neurons." J Neurosci Res 71(4): 591-9. Brefeldin A (BFA) is a fungus metabolite that is known to cause the disassembly of the Golgi complex and apoptosis in exposed cells, both of which have been suggested as playing roles in the pathogenesis of neurodegenerative diseases, particularly amyotrophic lateral sclerosis (ALS). This study showed that BFA caused neurotoxicity and apoptotic nuclear changes in cultured spinal neurons of rat spinal cord in a dose- and time-dependent manner. The spinal motor neurons were more vulnerable to this neurotoxicity. The cultured spinal neurons showed irreversible disassembly of the Golgi apparatus as early as 1 hr after exposure to BFA. BFA induced the expression and activation of caspase-12 beginning 8 hr after exposure. The level of the cleaved form of caspase-3 had increased 12 hr after the addition of BFA. Free radical generation and loss of mitochondrial membrane potential were observed in the later stages of neurotoxicity caused by BFA. Collectively, our data suggests that BFA is an excellent agent for reproducing the pathophysiological features of ALS. This in vitro model may be useful in attempts to study the mechanisms of this neurodegenerative disease and to examine therapeutic potentials.
Kim, S. H., J. S. Henkel, et al. (2003). "PARP expression is increased in astrocytes but decreased in motor neurons in the spinal cord of sporadic ALS patients." J Neuropathol Exp Neurol 62(1): 88-103. The evidence for increased oxidative stress and DNA damage in amyotrophic lateral sclerosis (ALS) prompted studies to determine if the expression of poly(ADP-ribose) polymerase (PARP) is increased in ALS. Using Western analyses of postmortem tissue, we demonstrated that PARP-immunoreactivity (PARP-IR) was increased 3-fold in spinal cord tissues of sporadic ALS (sALS) patients compared with non-neurological disease controls. Despite the increased PARP-IR, PARP mRNA expression was not increased significantly. Immunohistochemical analyses revealed PARP-IR was increased in both white and gray matter of sALS spinal cord. While PARP-IR was predominantly seen in astrocytes, large motor neurons displayed reduced staining compared with controls. This result contrasts sharply to the staining of Alzheimer and MPTP-induced Parkinson diseased tissue, where poly(ADP-ribose) (PAR)-IR was seen mostly in neurons, with little astrocytic staining. PARP-IR was increased in the pellet fraction of sALS homogenates compared with control homogenates, representing potential PARP binding to chromatin or membranes and suggesting a possible mechanism of PARP stabilization. The present results demonstrate glial alterations in sALS spinal cord tissue and support the role of glial alterations in sALS pathogenesis. Additionally, these results demonstrate differences in sALS spinal motor neurons and astrocytes compared to brain neurons and astrocytes in Alzheimer disease and MPTP-induced Parkinson disease despite the presence of markers for oxidative stress in all 3 diseases.
Kim, N. H., H. J. Kim, et al. (2003). "A novel SOD1 gene mutation in a Korean family with amyotrophic lateral sclerosis." J Neurol Sci 206(1): 65-9. BACKGROUND: Superoxide dismutase 1 (SOD1) gene mutations are responsible for approximately 20% of all familial amyotrophic lateral sclerosis (ALS) cases. However, these cases, especially those with SOD1 gene mutations, have not been reported in Korea. OBJECTIVES: The SOD1 gene in Korean family with ALS was screened for potential mutations and the clinical data was collected. MATERIALS AND METHODS: The clinical histories and neurological findings of the family members were obtained. Genomic DNA was isolated from the leukocytes of whole blood samples and the coding region of the SOD1 gene was analyzed by PCR and sequencing. RESULTS: The family with ALS showed a novel missense mutation in the SOD1 gene, which was heterozygous for the mutation, GGC to GTT, causing the substitution of valine for glycine at codon 10 (Gly10Val) in exon 1. Clinically, the patients exhibited early onset and rapid disease progression. CONCLUSIONS: Familial ALS with a novel Gly10Val mutation in the SOD1 gene showed severe clinical features. The mutation lies in a region involved in a dimer contact in the three-dimensional structure of the SOD1 protein. This study expands the number of ALS-associated SOD1 gene mutations.
Konagaya, M., T. Kato, et al. (2003). "A clinical and pathological study of a Japanese case of Amyotrophic Lateral Sclerosis/Parkinsonism-Dementia Complex with family history." J Neurol 250(2): 164-70. This report concerns a Japanese family with neuropathological findings consistent with amyotrophic lateral sclerosis/parkinsonism-dementia complex (ALS/PDC) in the Island of Guam. The proband was a 68-year-old woman with an 8-year history of parkinsonism which was followed by psychiatric symptoms and neurogenic amyotrophy 5 years after the onset. She had a family history of parkinsonism associated with dementia in all of her three siblings. They grew up in the Hobara village, a focus of amyotrophic lateral sclerosis in the Kii Peninsula of Japan in their childhood. Their parents were not consanguineous nor natives of the Kii Peninsula. The brain weight was 1040 g and there were mild frontal lobe atrophy, moderate atrophy of pes hippocampi, decoloration of the substantia nigra and locus coeruleus, and atrophy of the anterior root of the spinal cord. The microscopic examinations revealed degeneration of CA1 portion of the hippocampus to the parahippocampus gyrus, substantia nigra, locus coeruleus and spinal anterior horn with Bunina bodies. The spinal pyramidal tracts also mildly degenerated. Neurofibrillary tangles (NFT) were observed in the cerebral cortex, especially in the cortices from hippocampus to lateral occipitotemporal gyri, basal nucleus of Mynert, basal ganglia, thalamus, substantia nigra and widespread regions of the central nervous system through the brainstem to spinal cord including the nucleus of Onufrowitcz. In spite of a small amount of the senile plaques in the cerebral cortex and Lewy bodies in the substantia nigra and locus coeruleus, abundant NFT were distributed mainly in the third layer of the cerebral cortex, which is the characteristic feature of ALS/PDC. Thus, this was likely to be an ALS/PDC case outside the Guam Island. A tau mutation was not found on DNA analysis.
Kriz, J., G. Gowing, et al. (2003). "Efficient three-drug cocktail for disease induced by mutant superoxide dismutase." Ann Neurol 53(4): 429-36. There is currently no effective pharmacological treatment for amyotrophic lateral sclerosis (ALS). Because evidence suggests that multiple pathways may contribute to ALS pathogenesis, we tested in a mouse model of ALS (SOD1(G37R) mice) a combination approach consisting of three drugs for distinct targets in the complex pathway to neuronal death: minocycline, an antimicrobial agent that inhibits microglial activation, riluzole, a glutamate antagonist, and nimodipine, a voltage-gated calcium channel blocker. The efficacy of this three-drug cocktail was remarkable when administered in the diet from late presymptomatic stage (8-9 months). It delayed the onset of disease, slowed the loss of muscle strength, and increased the average longevity of SOD1(G37R) mice by 6 weeks. The protective effect of the treatment was corroborated by the reduced immunodetection signals for markers of gliosis and neurodegeneration in the spinal cord of SOD1(G37R) mice. These results indicate that such three-drug combination may represent an effective strategy for ALS treatment. Ann Neurol 2003
Ladewig, T., P. Kloppenburg, et al. (2003). "Spatial profiles of store-dependent calcium release in motoneurones of the nucleus hypoglossus from newborn mouse." J Physiol 547(Pt 3): 775-87. Hypoglossal motoneurones (HMN) are selectively damaged in both human amyotrophic lateral sclerosis (ALS) and corresponding mouse models of this neurodegenerative disease, a process which has been linked to their low endogenous Ca2+ buffering capacity and an exceptional vulnerability to Ca2+-mediated excitotoxic events. In this report, we investigated local Ca2+ profiles in low buffered HMNs by utilizing multiphoton microscopy, CCD imaging and patch clamp recordings in slice preparations. Bath application of caffeine induced highly localized Ca2+ release events, which displayed an initial peak followed by a slow 'shoulder' lasting several seconds. Peak amplitudes were paralleled by Ca2+-activated, apamin-sensitive K+ currents (IKCa), demonstrating a functional link between Ca2+ stores and HMN excitability. The potential involvement of mitochondria was investigated by bath application of CCCP, which collapses the electrochemical potential across the inner mitochondrial membrane. CCCP reduced peak amplitudes of caffeine responses and consequently IKCa, indicating that functionally intact mitochondria were critical for store-dependent modulation of HMN excitability. Taken together, our results indicate localized Ca2+ release profiles in HMNs, where low buffering capacities enhance the role of Ca2+-regulating organelles as local determinants of [Ca2+]i. This might expose HMN to exceptional risks during pathophysiological organelle disruptions and other ALS-related, cellular disturbances.
Li, C. Y. and F. C. Sung (2003). "Association between occupational exposure to power frequency electromagnetic fields and amyotrophic lateral sclerosis: A review." Am J Ind Med 43(2): 212-20. BACKGROUND: For the past two decades, there has been concern over electromagnetic exposure and human health. While most research has focused on cancer and reproductive outcomes, there is interest in the relationship between electromagnetic fields (EMF) and neurodegenerative diseases. METHODS: We review epidemiological findings and evidence regarding the association between occupational exposure to power frequency EMFs and amyotrophic lateral sclerosis (ALS). Medline was searched for citations related to occupational hazards and ALS, literature reviews and epidemiological evaluations. RESULTS: Nine out of the ten epidemiological studies that have been conducted on the risk of ALS in relation to occupational exposure to EMF show moderate to strong relative risk estimates that supported a link between them. Although data from these studies was consistent, the causal inference to a link between EMF exposure and ALS is restricted mainly due to the lack of direct information on EMF exposure and incomplete consideration of the other potential risk factors for ALS at workplaces. For instance, electric shock, in particular, is more common in electrical occupations than in any other occupations. CONCLUSIONS: This review concludes that further studies should consider investigating the separate effect of EMF exposure and electrical shocks to make more specific interpretations. On-site measurements of EMF should be conducted to include information on EMF exposure from residences as well as workplaces to improve exposure assessment. Am. J. Ind. Med. 43: 212-220, 2003.
Lomen-Hoerth, C., J. Murphy, et al. (2003). "Are amyotrophic lateral sclerosis patients cognitively normal?" Neurology 60(7): 1094-7. BACKGROUND: Patients with ALS are often told that the disease spares cognition; however, recent evidence suggests deficits in frontal executive skills occur in a sizable minority of ALS patients. In many instances, the frontal executive deficits represent the co-occurrence of frontotemporal lobar dementia (FTLD) and ALS. METHODS: Word generation, a simple frontal task that takes <2 minutes, was tested in 100 consecutive patients with ALS seen in the authors' multidisciplinary clinic. Any patient with a prior dementia diagnosis was excluded from the study. A subset of 44 patients agreed to undergo further neuropsychological testing and clinical interview to confirm or deny a diagnosis of dementia. RESULTS: Diminished word generation was found in one-third. Of the patients with abnormal word generation who agreed to further evaluation, nearly all were shown to meet research criteria for FTLD. In addition, one-quarter of the patients with normal word generation who agreed to further evaluation met research criteria for FTLD; these patients had new-onset personality changes. CONCLUSIONS: This study suggests that frontal executive deficits are present in half of ALS patients, many of whom meet strict research criteria for FTLD. Word generation tests are a useful screening tool in this cohort.
Lorenzl, S., D. S. Albers, et al. (2003). "Increased plasma levels of matrix metalloproteinase-9 in patients with Alzheimer's disease." Neurochem Int 43(3): 191-6. Matrix metalloproteinases (MMPs) may play a role in the pathophysiology of Alzheimer's disease (AD). MMP-9 and tissue inhibitors of metalloproteinases (TIMPs) are elevated in postmortem brain tissue of AD patients. MMPs and TIMPs are found in neurons, microglia, vascular endothelial cells and leukocytes. The aim of this study was to determine whether circulating levels of MMP-2, MMP-9, TIMP-1 and TIMP-2 are elevated in the plasma of AD patients. We compared AD patients to age- and gender-matched controls as well as to Parkinson's disease (PD) and amyotrophic lateral sclerosis (ALS) patients. There was constitutive expression of gelatinase A (MMP-2), and gelatinase B (MMP-9), in all the samples as shown by zymographic analysis. Levels of MMP-9 were significantly (P=0.003) elevated in the plasma of AD patients as compared to controls. Plasma levels of MMP-2, TIMP-1 and TIMP-2 were unchanged. There were no significant changes of MMP-2, MMP-9, TIMP-1 and TIMP-2 levels in PD and ALS samples. TIMP-1 and TIMP-2 were significantly correlated with MMP-9 in the AD patients. ApoE genotyping of plasma samples showed that levels of MMP-2, TIMP-1 and TIMP-2 and MMP-9 were not significantly different between the ApoE subgroups. These findings indicate that circulating levels of MMP-9 are increased in AD and may contribute to disease pathology.
Lorenzl, S., D. S. Albers, et al. (2003). "Tissue inhibitors of matrix metalloproteinases are elevated in cerebrospinal fluid of neurodegenerative diseases." J Neurol Sci 207(1-2): 71-6. Matrix metalloproteinases (MMPs) are implicated in the pathogenesis of diseases such as Alzheimer's Disease (AD) and amyotrophic lateral sclerosis (ALS). Increased expression of MMP-9 and TIMPs has been reported in postmortem AD and ALS brain tissue, as well as in ALS cerebrospinal fluid (CSF) and plasma. Although individual studies of MMP and TIMP expression in CSF have included AD and ALS samples, there are no studies comparing the expression of these proteins between neurodegenerative diseases. We measured the levels of matrix metalloproteinases (MMPs)-2 and -9 and the tissue inhibitor of MMPs (e.g. TIMP-1 and TIMP-2) in CSF samples from patients with Parkinson's Disease (PD), Huntington's Disease (HD), AD and ALS as compared to age-matched control patients. There was constitutive expression of the proform of gelatinase A (proMMP-2) on zymography gels in all CSF samples. Unexpectedly, there was an additional gelatinolytic band at 130 kDa of unknown etiology in the CSF samples of patients with PD (61% of patients studied), AD (61%), HD (25%) and ALS (39%). Levels of TIMP-1 were significantly elevated in CSF samples from all disease groups. TIMP-2 was significantly increased in CSF of AD and HD patients. MMP-2 levels did not differ significantly between groups. These findings show that TIMPs are elevated in the CSF of patients with neurodegenerative diseases suggesting a potential role of these endogenous inhibitors of matrix metalloproteinases in neurodegenerative diseases.
Lou, J. S., A. Reeves, et al. (2003). "Fatigue and depression are associated with poor quality of life in ALS." Neurology 60(1): 122-3. Twenty-five ALS subjects filled out five questionnaires: the ALS Functional Rating Scale, Multidimensional Fatigue Inventory, multidimensional McGill Quality of Life, Center of Epidemiologic Study--Depression Scale, and the Epworth Sleepiness Scale. Fatigue, depression, and excessive somnolence are more pronounced in ALS subjects than in normal controls. Both fatigue and depression are associated with poorer quality of life in subjects with ALS, and should be treated aggressively.
Lu, Y. Y., L. J. Wang, et al. (2003). "Intramuscular injection of AAV-GDNF results in sustained expression of transgenic GDNF, and its delivery to spinal motoneurons by retrograde transport." Neurosci Res 45(1): 33-40. Adeno-associated virus (AAV) vector has been developed as an attractive gene delivery system with proven safety. Glial cell line-derived neurotrophic factor (GDNF) is proposed to be a promising therapeutic agent for amyotrophic lateral sclerosis (ALS) and other motor neuron diseases. The purpose of this report was to investigate transgenic GDNF expression at different time points post AAV mediated GDNF intramuscular delivery. An AAV vector was constructed to encode a recombinant fusion of GDNF tagged with a FLAG sequence at the C-terminal (AAV-GDNF) to distinguish it from its endogenous counterpart. A single intramuscular injection of AAV-GDNF led to substantial expression of transgenic GDNF which remained for at least 10 months in transduced gastrocnemius muscle. This transgenic GDNF was distributed in a large number of myofibers, mainly in the vicinity of the sarcolemma and predominantly concentrated at the sites of neuromuscular junctions (NMJs). Furthermore, transgenic GDNF, but not beta-galactosidase expressed as a control, was detected in the motoneurons that projected axons to the injected muscles, thus, indicating retrograde axonal transportation of the transgenic GDNF. This study provides a basis for a strategy of intramuscular AAV-GDNF delivery to protect motoneurons as a possible means of ALS treatment.
Majoor-Krakauer, D., P. J. Willems, et al. (2003). "Genetic epidemiology of amyotrophic lateral sclerosis." Clin Genet 63(2): 83-101. Amyotrophic lateral sclerosis (ALS) is a late onset, rapidly progressive and ultimately fatal neurological disorder, caused by the loss of motor neurons in the brain and spinal cord. Familial aggregation of ALS, with an age-dependent but high penetrance, is a major risk factor for ALS. Familial ALS (FALS) is clinically and genetically heterogeneous. Three genes and linkage to four additional gene loci have been identified so far and may either predominantly lead to ALS (ALSI-ALS6) or cause multisystem neurodegeneration with ALS as an occasional symptom (tauopathies, ALS-dementia complex). This review presents a tentative classification of the "major" ALS genes and ALS "susceptibility" genes, that may act as susceptibility factors for neurodegeneration in interaction with other genetic or environmental risk factors. Considering that mutations in ALS genes explain approximately 10% of familial as well as sporadic ALS, and most remaining cases of the discase are thought to result form the interaction of several genes and environmental factors, ALS is a paradigm for multifactorial discases.
Manabe, Y., I. Nagano, et al. (2003). "Glial cell line-derived neurotrophic factor protein prevents motor neuron loss of transgenic model mice for amyotrophic lateral sclerosis." Neurol Res 25(2): 195-200. Effects of glial cell line-derived neurotrophic factor (GDNF) were studied in transgenic (Tg) mice model for amyotrophic lateral sclerosis. GDNF protein or vehicle was injected three times a week from 35 weeks of age into the right gastrocnemius muscle of Tg mice carrying mutant human Cu/Zn superoxide dismutase gene, and histological analysis was performed at 46 weeks. Clinical data showed a tendency of improvement, but was not significantly different between the two animal groups. In contrast, total number of and phospho-Akt (p-Akt) positive large motor neurons in the treated side was significantly more preserved in GDNF-treated group than in vehicle group (p < 0.05). Immunoreactivity of phospho-ERK and active caspases-3 and -9 showed no difference. These results indicate that the intramuscular injection of GDNF protein prevented motor neuron loss while preserving survival p-Akt signal and without affecting caspase activations, suggesting a future possibility for the therapy of the disease.
Maragakis, N. J., M. Jackson, et al. (2003). "Topiramate protects against motor neuron degeneration in organotypic spinal cord cultures but not in G93A SOD1 transgenic mice." Neurosci Lett 338(2): 107-10. Topiramate is a novel anti-convulsant, structurally distinct from other known anti-convulsants. A number of independent studies suggest that topiramate has anti-excitotoxic properties. It has been found to diminish release of glutamate from neurons and block (-amino-3-hydoxy-5-methylisoxazole-4-proprionic acid glutamate receptor evoked currents. Since activation of non-N-methyl-D-aspartate glutamate receptors is thought to play a role in the selective loss of motor neurons in amyotrophic lateral sclerosis (ALS), we determined whether topiramate could protect against chronic glutamate-mediated motor neuron degeneration. An organotypic spinal cord culture system was used in which glutamate transport is inhibited by pharmacological blockade. After 3 weeks of treatment, topiramate was found to significantly prevent motor neuron degeneration in this culture model. However, the drug did not increase survival in G93A SOD1 transgenic mice, an animal model of ALS. These studies suggest that topiramate could be useful as a neuroprotectant, but were not effective in more complex motor injury paradigms such as the mouse model of ALS.
Marques, S. A., M. Taffarel, et al. (2003). "Participation of neurofilament proteins in axonal dark degeneration of rat's optic nerves." Brain Res 969(1-2): 1-13. NEUROFILAMENTS (NF) ARE NEURONAL INTERMEDIATE FILAMENTS FORMED BY THREE DIFFERENT SUBUNITS: high (NF-H), medium (NF-M) and light (NF-L). They are responsible for the determination and maintenance of axon caliber. Accumulation of NF or their immunoreactive products are components of several neurodegenerative disease lesions, such as neurofibrillary tangles, Lewy bodies and the spheroids of amyotrophic lateral sclerosis. Also, cytoskeletal breakdown is one of the first ultrastructural changes occurring after nerve crush or section. In the present study, Wistar rats were subjected to bilateral enucleation to induce Wallerian degeneration of optic nerve fibers and perfused 24 h, 48 h and 1 week later. Optic nerve segments were processed for electron microscopy (EM), light microscopy immunofluorescence (LM) and immunoelectronmicroscopy (IEM) for NF subunit detection. LM for NF of control nerves showed a slightly different pattern and intensity for each subunit, with more intense staining of NF-M and NF-H and less intense staining of NF-L. This reaction did not change considerably at 48 h, but was severely reduced 1 week after enucleation. Results of EM showed fibers in: (1) partial cytoskeleton degeneration or (2) watery degeneration or (3) dark degeneration. The number of dark degenerating axons was statistically higher at the latest time-interval studied. Neurofilament clumping areas and dark degenerating axons showed positive immunostaining for the three neurofilaments subunits when examined by IEM. These results suggest that dark degenerating axons develop from areas of neurofilament aggregation. We may also conclude that NF proteins participate in the process of axonal dark degeneration.
Mathisen, P. M. (2003). "Gene discovery and validation for neurodegenerative diseases." Drug Discov Today 8(1): 39-46. Treatment of neurodegenerative diseases, such as Alzheimer's disease, multiple sclerosis, Parkinson's disease and amyotrophic lateral sclerosis (ALS), represents a major challenge for the pharmaceutical industry. These disorders have common and unique molecular pathological characteristics that result in serious reductions in nervous-system functionality. Key to developing novel and efficacious therapeutics is the discovery of new gene targets. Genomic, proteomics and bioinformatic analyses are identifying vast amounts of genes whose expression is associated with the pathology of a specific disease. Extensive validation studies performed in parallel with drug development are crucial for the selection of appropriate target genes. This review outlines some of the current progress in gene discovery for neurodegenerative disease.
Mitchell, J. D. and M. R. O'Brien (2003). "Quality of life in motor neurone disease--towards a more practical assessment tool?" J Neurol Neurosurg Psychiatry 74(3): 287-8.
Mockett, R. J., S. N. Radyuk, et al. (2003). "Phenotypic effects of familial amyotrophic lateral sclerosis mutant Sod alleles in transgenic Drosophila." Proc Natl Acad Sci U S A 100(1): 301-6. A subset of patients suffering from familial amyotrophic lateral sclerosis (FALS) exhibit point mutations in the gene encoding Cu-Zn superoxide dismutase [superoxide:superoxide oxidoreductase, EC (SOD)]. The human wild-type and five FALS Sod mutant transgenes were introduced into the fruit fly, Drosophila melanogaster, in a Cu-Zn Sod null background. Sod null flies had dramatically decreased life span, glutathione and methionine content, fertility, locomotor activity, and resistance to hyperoxic stress, compared with wild-type controls. All of these phenotypic manifestations were rescued fully by a single human wild-type allele, expressing 5-10% of wild-type SOD activity. Full recovery of wild-type life span was also observed when human mutant and wild-type alleles were placed together in the fly Sod null background. The FALS Sod mutations alone caused a recessive phenotype, usually involving low or undetectable levels of SOD activity, in which: (i) full restoration of the wild-type phenotype was observed among young adults, and (ii) older adults exhibited a sudden increase in oxidative stress, accompanied by physiological impairment of abrupt onset, and followed by premature death. Thus, the minimal SOD activity associated with the FALS Sod mutations appears to determine longevity, not by chronically increasing oxidative stress, but by limiting the time in which a viable redox environment can be maintained. However, the dominant gain of function by mutant SOD, which occurs in human patients and in the transgenic mouse model of FALS, is not observed in Drosophila.
Monaco, E. A., 3rd and M. L. Vallano (2003). "Cyclin-dependent kinase inhibitors: cancer killers to neuronal guardians." Curr Med Chem 10(5): 367-79. The development of small molecule kinase inhibitors as potential cancer therapeutics is an area of intense interest, and a subset of these agents target cyclin-dependent kinase (CDK) activity. Ten distinct CDKs (1-9, 11), when paired with their cyclin activators, are integral to such diverse processes as cell cycle control, neuronal development, and transcriptional regulation. Mutation and/or aberrant expression of certain CDKs and their regulatory counterparts are associated with uncontrolled proliferation and tumorigenesis. As such, CDK selective inhibitors (CDKIs) that attenuate or prevent tumor growth have been developed. Recently, interest in the therapeutic potential of CDKIs has expanded to include neurodegenerative diseases, where dysregulated CDK activity has been linked to the pathogenesis of Alzheimer's disease (AD), amyotrophic lateral sclerosis (ALS), and stroke. Specifically, aberrant activation of cell cycle CDKs or CDK5 is associated with apoptosis and neuronal dysfunction in response to various neuronal stressors. To date, CDKIs have shown promise as neuroprotective agents in the research laboratory and, in the future, may prove useful in the neurology clinic.
Moris, G. and J. Vega (2003). "[Neurotrophic factors: basis for their clinical application]." Neurologia 18(1): 18-28. Neurotrophic factors are molecules that regulate neuronal survival, nervous system plasticity and many other physiological functions of neuronal and glial cells, as well as some non-neuronal tissues. They have been involved in the etiopathogenesis of some neurodegenerative disorders, and some of them have been proposed as potential treatments for these diseases on the basis of in vitro experiments and animal models. The main neurotrophic factor families with potential therapeutic applications include the family of neurotrophins (NGF, BDNF or NT-3), GDNF and related neurotrophic factor, CNTF and the members of the IGF family. Some of these molecules have already been tested in clinical trials with contradictory results. One of the major challenges to their clinical use is the difficulty to deliver them into the central nervous system. Nevertheless, solid rational exists for the possible use of neurotrophic factors in the treatment of Alzheimer's and Parkinson's diseases, peripheral neuropathies or amyotrophic lateral sclerosis. This review compiles the essential aspects of neurotrophic factors and the current studies of their clinical relevance and therapeutic potentialities. Future directions for further research are also discussed. Neurologia 2003;18(1):18-28
Nagano, S., Y. Fujii, et al. (2003). "The efficacy of trientine or ascorbate alone compared to that of the combined treatment with these two agents in familial amyotrophic lateral sclerosis model mice." Exp Neurol 179(2): 176-80. One of the hypotheses regarding the pathogenesis of familial ALS (FALS) is a copper-mediated oxidative toxicity derived from the mutant Cu, Zn-superoxide dismutase (SOD1). We have previously demonstrated the efficacy of the combined treatment with a copper chelator (trientine) and an antioxidant (ascorbate) on the disease expression of the FALS-linked mutated SOD1 transgenic mice. Here, we investigated the efficacy of trientine or ascorbate alone on FALS mice when administered before or after the onset of the disease. The mice with a high dose of trientine or ascorbate administered before the onset survived significantly longer than the control. In the combined treatment with a high dose of trientine and ascorbate initiated before the onset, survival lengthened and the motor function of the mice remained more significantly than the control. None of the treatments affected the mean age of the onset, and none of the agents administered after the onset prolonged survival. These findings suggest that better outcomes may be expected by the administration of these agents at the preonset stage of the disease, and the combination of the agents acting on different sites might be useful in preserving the motor performance in FALS.
Nakamizo, T., J. Kawamata, et al. (2003). "Phosphodiesterase inhibitors are neuroprotective to cultured spinal motor neurons." J Neurosci Res 71(4): 485-95. We have previously reported that cyclic guanosine-3',5'-monophosphate (cGMP) protects spinal motor neurons against acute reactive oxygen species (ROS)-induced toxicity but not against chronic ROS-induced or glutamate (Glu)-induced toxicity. In this study, we investigated the effects of phosphodiesterase (PDE) inhibitors on the survival of cultured spinal motor neurons. Selective PDE5 inhibitors (dipyridamole, T-1032, and zaprinast) as well as a nonselective PDE inhibitor (aminophylline) protected motor and nonmotor neurons against both acute ROS-induced and chronic Glu-induced neurotoxicity, whereas selective inhibitors of PDE1-4 offered no protection. 8-Bromo-cGMP (8br-cGMP), a cGMP analogue, protected both motor and nonmotor neurons against acute ROS-induced toxicity but protected only nonmotor neurons against chronic Glu-induced toxicity. This neuroprotection was blocked by KT5823, a cGMP-dependent protein kinase (PKG) inhibitor. Immunohistochemical staining confirmed that PDE5 and PKG are located in almost all rat lumbar spinal neurons. Furthermore, semiquantitative analysis of the immunostaining intensity revealed that PDE5 was more abundant in motor neurons than in nonmotor neurons. Our results suggest that this difference in the amount of PDE5 may be responsible for the vulnerability of motor neurons to chronic excitotoxicity. In addition, the results of this study raise the possibility that PDE5 inhibitors might be used as a treatment for amyotrophic lateral sclerosis.
Nguyen, M. D., M. Boudreau, et al. (2003). "Cell cycle regulators in the neuronal death pathway of amyotrophic lateral sclerosis caused by mutant superoxide dismutase 1." J Neurosci 23(6): 2131-40. There is growing evidence for involvement of members of the cyclin-dependent kinase (Cdk) family in neurodegenerative disorders and in apoptotic death of neurons subjected to various insults. After our recent report that a deregulation of Cdk5 activity by p25 may contribute to pathogenesis of amyotrophic lateral sclerosis (ALS), we further examined the possible involvement of other Cdks in mice expressing a mutant form of superoxide dismutase (SOD1(G37R)) linked to ALS. No substantial changes in Cdk2 or Cdk6 distribution and kinase activities were detected in spinal motor neurons from SOD1(G37R) mice when compared with normal mice. Of particular interest was the upregulation and mislocalization of Cdk4, a regulator of the G1-S checkpoint of the cell cycle, in motor neurons of SOD1(G37R) mice. The increase of Cdk4 activity in SOD1(G37R) mice was associated with an increase in nuclear Cdk4, cyclin D1, its coactivator, and with the abnormal phosphorylation of the retinoblastoma (Rb) protein at Cdk phosphorylation sites. Pharmacological treatment of SOD1(G37R) mice with minocycline, a compound that attenuates microgliosis and slows down disease, lessened the dysregulation of Cdk5/Cdk4 and the phosphorylation of Rb. Interestingly, phospho-Rb was immunoprecipitated with anti-Cdk4 but not with anti-Cdk5 antibodies, suggesting a key role for Cdk4 in the phosphorylation of Rb. Remarkably, the overexpression of a transgene coding for human neurofilament H, a phosphorylation sink for deregulated Cdk5 activity by p25, resulted in a reduction in levels of nuclear Cdk4 and Rb phosphorylation. These results indicate that a cell cycle signaling at the neuronal G1-S checkpoint subsequent to Cdk5 deregulation may constitute a critical step of the neuronal death pathway in ALS caused by mutant SOD1.
Ostojic, J., K. Axelman, et al. (2003). "No evidence of linkage to chromosome 9q21-22 in a Swedish family with frontotemporal dementia and amyotrophic lateral sclerosis." Neurosci Lett 340(3): 245-7. Frontotemporal dementia (FTD) is a neurodegenerative disorder, sometimes occurring together with amyotrophic lateral sclerosis (ALS) within the same family. Recently, a region on chromosome 9q21-22 was reported to harbour a locus that may participate in both disorders [Hosler, B.A., et al., JAMA., 284 (2000) 1664-1669]. In the present study, a Swedish pedigree with both ALS and FTD segregating in the family was investigated by linkage analysis with five markers on chromosome 9q21-22. The pedigree included 17 individuals in two generations, with five affected cases available for analysis. As two-point logarithm of odds scores close to zero were obtained for all markers tested, the region on chromosome 9q21-22 is suggested to be excluded as candidate region in this Swedish FTD/ALS family. Our conclusion is therefore that additional loci involved in these two disorders must be operating.
Pamphlett, R. and S. Kum-Jew (2003). "Zinc in the spinal cord of a mutant SOD1 mouse model of ALS." Neuroreport 14(4): 547-9. Both decreases and increases in zinc have been implicated in the pathogenesis of amyotrophic lateral sclerosis (ALS). We therefore examined the distribution of zinc in transgenic mutant superoxide dismutase 1 (SOD1) mice, a model for ALS. Frozen sections of spinal cord from these mice were stained for free zinc with autometallography. Zinc granules in the spinal anterior horn surrounded motor neuron cell bodies and their processes. The same distribution of zinc was seen in wildtype mice. The onset of weakness in the mutant SOD1 mice did not alter the zinc distribution. Changes in the tissue distribution of free zinc do not appear to play a role in the pathogenesis of mutant SOD1-associated ALS.
Pessolano, F. A., A. A. Suarez, et al. (2003). "Nutritional assessment of patients with neuromuscular diseases." Am J Phys Med Rehabil 82(3): 182-5. OBJECTIVE: To study the nutritional status of patients with Duchenne muscular dystrophy and amyotrophic lateral sclerosis. DESIGN: A total of 34 Duchenne muscular dystrophy and seven amyotrophic lateral sclerosis patients were studied. Body mass index, patient's body weight for zero muscle mass as a percentage of the theoretical weight for zero muscle mass, and creatinine-height index were calculated. RESULTS: Substantial differences were found between body mass index and percentage of expected weight for zero muscle mass. No amyotrophic lateral sclerosis patients were classified as overweight by body mass index, whereas five were overweight by the percentage of expected weight for zero muscle mass method. Five Duchenne muscular dystrophy patients were classified as overweight by body mass index, and 30 were overweight by the percentage of expected weight for zero muscle mass. According to the creatinine-height index, no patient with amyotrophic lateral sclerosis or Duchenne muscular dystrophy showed normal body muscle mass. No correlation was found between creatinine-height index, percentage of expected weight for zero muscle mass, and body mass index. CONCLUSIONS: The body mass index should be used with caution for the evaluation of the nutritional status of patients with amyotrophic lateral sclerosis and Duchenne muscular dystrophy. Indices that incorporate the assessment of the compartmental distribution of muscle and fat are more sensitive.
Piao, Y. S., K. Wakabayashi, et al. (2003). "Neuropathology with clinical correlations of sporadic amyotrophic lateral sclerosis: 102 autopsy cases examined between 1962 and 2000." Brain Pathol 13(1): 10-22. Sporadic amyotrophic lateral sclerosis (ALS) is a fatal neurological disorder affecting adults. We studied the neuropathology and clinical correlations in 102 autopsy cases of ALS. The age at onset of the disease was significantly higher for the bulbaronset form (30 cases) than for the limb-onset form (72 cases). Dementia was confirmed in 7 cases. These 102 cases were divided into 4 pathological subgroups: typical ALS (59 cases), lower-motor-predominant ALS (23 cases), ALS with temporal lesions (18 cases), and ALS with pallido-nigro-luysian degeneration (2 cases). The age at onset was significantly higher for lower-motor-predominant ALS and ALS with temporal lesions than for typical ALS. In the lower motor neurons, Bunina bodies were detected in 88 cases, whereas ubiquitin-immunoreactive skein and/or spherical inclusions were detected in all 102 cases. Of the 100 available cases, 50 and 16 also showed ubiquitin-immunoreactive inclusions in the neostriatal and temporal small neurons, respectively. Ubiquitin-immunoreactive dystrophic neurites were also observed in the neostriatum in 3 of the 50 cases with neostriatal inclusions, and in the temporal cortex in 4 of the 16 cases with temporal inclusions. There was a significant association between the bulbar-onset form, temporal lesions, neostriatal inclusions and temporal inclusions, and between dementia, temporal lesions and temporal inclusions. Neostriatal and temporal dystrophic neurites were associated with dementia and bulbar-onset form through temporal lesions and temporal inclusions. The present findings may be helpful for designing further studies on the mechanisms underlying the development of ALS.
Plato, C. C., R. M. Garruto, et al. (2003). "Amyotrophic lateral sclerosis and parkinsonism-dementia complex of Guam: changing incidence rates during the past 60 years." Am J Epidemiol 157(2): 149-57. In the 1950s, the incidence of amyotrophic lateral sclerosis (ALS, or Lytico) and parkinsonism-dementia complex (PDC, or Bodig) on the island of Guam was much higher than anywhere else in the world. From the late 1960s to the early 1980s, the incidence of both disorders has decreased. The objective of the present study was to ascertain whether the decreasing incidence continued until the end of the century (1999). The average annual incidence of ALS and PDC was calculated for each 5-year period from 1940 to 1999, utilizing registration records of all ALS and PDC cases on Guam during that period. The results of this study confirmed that the incidence of ALS declined steadily during the past 40 years. The incidence of PDC also declined until the late 1980s but, unlike ALS, showed a slight increase from 1980 to 1999. The rapid decrease in incidence is not likely to be due to genetic factors. Instead, it is most likely to be the results of radical socioeconomic, ethnographic, and ecologic changes brought about by the rapid westernization of Guam.
Pompl, P. N., L. Ho, et al. (2003). "A therapeutic role for cyclooxygenase-2 inhibitors in a transgenic mouse model of amyotrophic lateral sclerosis." Faseb J 17(6): 725-7. Recent studies indicate that the proinflammatory enzyme cyclooxygenase (COX)-2, an enzyme involved in inflammatory cascades but also normal neuronal activities, is elevated in the brain and spinal cord of amyotrophic lateral sclerosis (ALS) patients and ALS mouse model systems. On the basis of this evidence, we explored the impact of COX-2 inhibition on the onset and progression of ALS-like disease in the G93A human superoxide dismutase (SOD)1 mouse model of ALS. We found that prophylactic administration of nimesulide, a preferential COX-2 inhibitor, in the feed resulted in a significant delay in the onset of ALS type motor impairment. This delay of ALS symptomatology temporally overlapped with the inhibition of prostaglandin E2 elevation in the spinal cord of SOD1-G93A transgenic mice relative to untreated SOD1-G93A controls. This study strongly supports a role for COX-2 in the pathophysiology of ALS and provides the first experimental evidence that prophylactic treatment with COX-2 inhibitors can significantly delay the onset of motor dysfunction in the SOD1-G93A transgenic mouse model of ALS.
Potter, S. Z. and J. S. Valentine (2003). "The perplexing role of copper-zinc superoxide dismutase in amyotrophic lateral sclerosis (Lou Gehrig's disease)." J Biol Inorg Chem. The existence of a link between some cases of familial amyotrophic lateral sclerosis (FALS) and copper-zinc superoxide dismutase (CuZnSOD) has been understood for almost a decade. However, beyond the fact that mutations in CuZnSOD cause FALS by a toxic gain of function, the mechanism whereby specific mutations in the protein structure result in development of the disease has remained almost a complete mystery to date. We have undertaken a critical survey of in vitro characteristics of over 30 of the 90 different CuZnSOD mutant proteins that are known to cause FALS in order to determine the differences that exist between mutant and wild-type properties. As-isolated metal content analysis, SOD activity assays, and thermal stability determinations of a significant fraction of the mutants show that the FALS mutant SOD proteins can be classified distinctly into one of two groups. Members of the first group, termed wild-type-like, have physical properties and enzymatic activities that are strikingly similar to those of wild-type CuZnSOD. The second group, however, show aberrant metal content in the as-isolated forms, compromised SOD activities, and unusual DSC thermoscans. All mutations in the members of this second group occur in or near the metal binding sites of the protein and thus they are termed metal binding region mutants. We have also compared the relative rates of self-inactivation caused by reaction of the wild-type protein and several FALS-linked CuZnSOD mutants with hydrogen peroxide, as a measure of relative peroxidative activities. Results and implications of the role of CuZnSOD in FALS are discussed.
Przedborski, S., H. Mitsumoto, et al. (2003). "Recent advances in amyotrophic lateral sclerosis research." Curr Neurol Neurosci Rep 3(1): 70-7. Amyotrophic lateral sclerosis (ALS) is the most common motor neuron disease in adults. Despite several genetic breakthroughs, the actual cause and mechanism of neurodegeneration in ALS remains a mystery. Nevertheless, recent scientific and clinical advances have led to the development of new therapeutic strategies for this progressive, fatal disorder. We review the progress of the most recent clinical trials in ALS, taking into account some of the hurdles encountered by these studies. We also discuss the potential role of retroviral infection as a cause or contributor to ALS, which is one of the most recent hypotheses for the pathogenesis of the disease. The genetic background of ALS is summarized and special attention is given to the newly identified ALS gene ALS2, and to those that are currently being investigated. The last part of this review is dedicated to the mutation in superoxide dismutase-1 (SOD1). The hypothesized deleterious mechanisms of mutant SOD1 are discussed, as well as the possibilities that the mutant protein activates the apoptotic cell death process and that these molecular alterations can be exploited to devise experimental neuroprotective therapies.
Raiteri, L., E. Paolucci, et al. (2003). "Activation of a glycine transporter on spinal cord neurons causes enhanced glutamate release in a mouse model of amyotrophic lateral sclerosis." Br J Pharmacol 138(6): 1021-1025. The release of [(3)H]D-aspartate ([(3)H]D-ASP) or [(3)H]GABA evoked by glycine from spinal cord synaptosomes was compared in mice expressing mutant human SOD1 with a Gly(93) Ala substitution ([SOD1-G93A(+)]), a transgenic model of amyotrophic lateral sclerosis, and in control mice. Mice expressing mutated SOD1 were killed at the advanced phase of the pathology, when they showed signs of ingestion disability, because of paralysis of the posterior limbs. In control mice glycine concentration-dependently evoked [(3)H]D-ASP and [(3)H]GABA release. Potentiation of the spontaneous release of both amino acids is likely to be mediated by activation of a glycine transporter, since the effects of glycine were counteracted by the glycine transporter blocker glycyldodecylamide but not by the glycine receptor antagonists strychnine and 5,7-dichlorokynurenate. The glycine-evoked release of [(3)H]D-ASP, but not that of [(3)H]GABA, was significantly more pronounced in SOD1-G93A(+) than in control animals. British Journal of Pharmacology(2003) 138, 1021-1025. doi:10.1038/sj.bjp.0705142
Ranganathan, S. and R. Bowser (2003). "Alterations in G(1) to S Phase Cell-Cycle Regulators during Amyotrophic Lateral Sclerosis." Am J Pathol 162(3): 823-35. Amyotrophic lateral sclerosis (ALS) is characterized by progressive degeneration of the motor neurons in the cerebral cortex, brain stem, and spinal cord. However, the mechanisms that regulate the initiation and/or progression of motor neuron loss in this disease remain enigmatic. Cell-cycle proteins and transcriptional regulators such as cyclins, cyclin-associated kinases, the retinoblastoma gene product (pRb), and E2F-1 function during cellular proliferation, differentiation, and cell death pathways. Recent data has implicated increased expression and activation of various cell-cycle proteins in neuronal cell death. We have examined the expression and subcellular distribution of G(1) to S phase cell-cycle regulators in the spinal cord, motor cortex, and sensory cortex from clinically and neuropathologically diagnosed sporadic ALS cases and age-matched controls. Our results indicate hyperphosphorylation of the retinoblastoma protein in motor neurons during ALS, concurrent with increased levels of cyclin D, and redistribution of E2F-1 into the cytoplasm of motor neurons and glia. These data suggest that G(1) to S phase activation occurs during ALS and may participate in molecular mechanisms regulating motor neuron death.
Rao, S. D., H. Z. Yin, et al. (2003). "Disruption of glial glutamate transport by reactive oxygen species produced in motor neurons." J Neurosci 23(7): 2627-33. Observations of elevated CSF glutamate in amyotrophic lateral sclerosis (ALS), together with findings that motor neurons are selectively vulnerable to glutamate receptor-mediated ("excitotoxic") injury, support an excitotoxic contribution to the motor neuron loss in the disease. However, the basis of the apparent loss of astrocytic glutamate transport capacity in affected areas of motor cortex and spinal cord, which probably underlies the extracellular glutamate elevations, is unexplained. Here, we find that glutamate induces far greater reactive oxygen species (ROS) generation in cultured motor neurons than in other spinal neurons. In addition, we found that the ROS seem to be able to leave the motor neurons and induce oxidation and disruption of glutamate uptake in neighboring astrocytes. Correspondingly, in a transgenic mouse model of ALS, protein oxidation was increased in regions immediately surrounding motor neurons. These results provide a mechanism that can account for the localized loss of glial glutamate transport seen in the disease. Furthermore, the observations lend support for a feedforward model involving reciprocal interactions between motor neurons and glia, which may prove useful in understanding ALS pathogenesis.
Riggs, J. E. and G. R. Hobbs (2003). "Motor axonal injury and amyotrophic lateral sclerosis: risk assessment using a reverse probability analysis technique." Mil Med 168(2): 143-5. A relationship between antecedent trauma and amyotrophic lateral sclerosis (ALS) has been clinically suspected for over a century. Nine cases of ALS that occurred over a 14-year period in young U.S. men (age range, 28-43 years) following trauma that produced motor axonal injury that antedated (range, 5-42 months) the onset of ALS have been reported by a single neurologist. After estimating the number of cases of ALS in 28- to 43-year-old American men that would be expected to occur over a 14-year period, a reverse probability analysis technique was used to determine the expected incidence rates of motor axonal injury in a ideally matched control population that would give probabilities of 0.05, 0.01, and 0.001 of observing nine or more instances of motor axonal injury occurring during the previous 5 to 42 months. This analysis was repeated assuming that this one neurologist had only reported 50 and 10% of all instances of ALS that occurred during this 14-year period in American men ages 28 to 43 years who had experienced trauma that produced motor axonal injury that occurred 5 to 42 months before the onset of ALS. Reverse probability analysis is a technique that can be used in performing risk assessments.
Rivara, C. B., C. C. Sherwood, et al. (2003). "Stereologic characterization and spatial distribution patterns of Betz cells in the human primary motor cortex." Anat Rec 270A(2): 137-51. Betz cells are giant motoneurons located in layer Vb of the primate primary motor cortex. We conducted stereological analyses of Betz cells and neighboring pyramidal cells from the brains of six neurologically normal elderly humans to determine their volume, total number, and spatial distribution, and to relate these data to functional localization. The distribution of cellular volumes exhibits a bimodal pattern, delineating two different subpopulations. Betz cell volumes follow a mediolateral gradient, the largest Betz cells being located on the most medial part of the motor cortex. Additionally, the shape of Betz cells varies between the rostral and caudal parts of the primary motor cortex, supporting the notion that there are anatomically distinct zones in primary motor cortex. The total number of Betz cells per hemisphere accounts for about one-tenth of the total number of pyramidal cells in layer Vb. Analysis of spatial distribution using Voronoi tessellation revealed maximal clustering of Betz cells in a zone situated two-thirds from the midline along the mediolateral axis of the primary motor cortex. These data suggest that Betz cells have a discrete subregional distribution that may correspond to certain aspects of the functional parcellation of area 4. These results may offer a histological correlate of functional imaging studies and are relevant in the context of neurodegenerative diseases such as amyotrophic lateral sclerosis, progressive supranuclear palsy, and Guamanian amyotrophic lateral sclerosis/Parkinsonism-dementia, and in studies of normal brain aging. Anat Rec Part A 270A:137-151, 2003.
Rizzardini, M., M. Lupi, et al. (2003). "Mitochondrial dysfunction and death in motor neurons exposed to the glutathione-depleting agent ethacrynic acid." J Neurol Sci 207(1-2): 51-8. This study investigated the mechanisms of toxicity of glutathione (GSH) depletion in one cell type, the motor neuron. Ethacrynic acid (EA) (100 microM) was added to immortalized mouse motor neurons (NSC-34) to deplete both cytosolic and mitochondrial glutathione rapidly. This caused a drop in GSH to 25% of the initial level in 1 h and complete loss in 4 h. This effect was accompanied by enhanced generation of reactive oxygen species (ROS) with a peak after 2 h of exposure, and by signs of mitochondrial dysfunction such as a decrease in 3-(4,5-dimethyl-2-thiazoyl)-2,5-diphenyltetrazolium bromide (MTT) (30% less after 4 h). The increase in ROS and the MTT reduction were both EA concentration-dependent. Expression of heme oxygenase-1 (HO-1), a marker of oxidative stress, also increased. The mitochondrial damage was monitored by measuring the mitochondrial membrane potential (MMP) from the uptake of rhodamine 123 into mitochondria. MMP dropped (20%) after only 1 h exposure to EA, and slowly continued to decline until 3 h, with a steep drop at 5 h (50% decrease), i.e. after the complete GSH loss. Quantification of DNA fragmentation by the TUNEL technique showed that the proportion of cells with fragmented nuclei rose from 10% after 5 h EA exposure to about 65% at 18 h. These results indicate that EA-induced GSH depletion rapidly impairs the mitochondrial function of motor neurons, and this precedes cell death. This experimental model of oxidative toxicity could be useful to study mechanisms of diseases like spinal cord injury (SCI) and amyotrophic lateral sclerosis (ALS), where motor neurons are the vulnerable population and oxidative stress has a pathogenic role.
Robertson, J., M. M. Doroudchi, et al. (2003). "A neurotoxic peripherin splice variant in a mouse model of ALS." J Cell Biol 160(6): 939-49. Peripherin, a neuronal intermediate filament (nIF) protein found associated with pathological aggregates in motor neurons of patients with amyotrophic lateral sclerosis (ALS) and of transgenic mice overexpressing mutant superoxide dismutase-1 (SOD1G37R), induces the selective degeneration of motor neurons when overexpressed in transgenic mice. Mouse peripherin is unique compared with other nIF proteins in that three peripherin isoforms are generated by alternative splicing. Here, the properties of the peripherin splice variants Per 58, Per 56, and Per 61 have been investigated in transfected cell lines, in primary motor neurons, and in transgenic mice overexpressing peripherin or overexpressing SOD1G37R. Of the three isoforms, Per 61 proved to be distinctly neurotoxic, being assembly incompetent and inducing degeneration of motor neurons in culture. Using isoform-specific antibodies, Per 61 expression was detected in motor neurons of SOD1G37R transgenic mice but not of control or peripherin transgenic mice. The Per 61 antibody also selectively labeled motor neurons and axonal spheroids in two cases of familial ALS and immunoprecipitated a higher molecular mass peripherin species from disease tissue. This evidence suggests that expression of neurotoxic splice variants of peripherin may contribute to the neurodegenerative mechanism in ALS.
Rodriguez, G. E., I. M. Califano, et al. (2003). "[Amyotrophic lateral sclerosis: its relationship with thyroid function and phosphate calcium metabolism]." Rev Neurol 36(2): 104-8. INTRODUCTION. Amyotrophic lateral sclerosis (ALS) is a progressive degenerative disease involving motor neurons of the spinal cord, brain stem, and motor cortex. Previous studies reported the coexistence of motor neuron disease with thyroid dysfunction and primary hyperparathyroidism. These findings suggested an eventual role of the previously mentioned endocrine disorders and the development of ALS. OBJECTIVE. Identify thyroid dysfunction and changes in mineral metabolism in patients affected by sporadic ALS. PATIENTS AND METHODS. We retrospectively analyzed data from 41 in ward patients from June 1998, to June 2001. All of them were diagnosed with sporadic ALS. The following laboratory test were performed: thyrotropin (TSH), thyroxine (T4), serum calcium, serum phosphate, parathyroid hormone (PTH) and ionic calcium concentrations. RESULTS. None of the studied patients was found to be hyperthyroid. Two patients had elevated TSH and normal T4, these findings suggested subclinical hypothyroidism. Elevated PTH was found in one patient; another had primary hyperparathyroidism. Low serum calcium was found in three patients and elevated phosphate was found in another four. CONCLUSIONS. All these findings do not allow us to assert a pathogenic association between thyroid dysfunction or alteration of phosphate calcium metabolism and ALS.
Roscoe, L. A., J. E. Malphurs, et al. (2003). "Antecedents of euthanasia and suicide among older women." J Am Med Womens Assoc 58(1): 44-8. OBJECTIVES: To identify the characteristics of older women who sought Jack Kevorkian's assistance in dying and to compare them with those of an age-matched sample who committed suicide. METHOD: This retrospective case-control study compared all 18 women age 55 and older who died with the assistance of Jack Kevorkian and whose deaths were investigated in Oakland County, Michigan from 1995 to 1997 with all 15 women age 55 and older who committed suicide in the same county during the same time period. We coded 203 variables in 7 domains from medical examiner files, including autopsy findings. RESULTS: Significantly more of Kevorkian's cases had amyotrophic lateral sclerosis or multiple sclerosis (p = .018), a recent decline in health (p = .031), or inadequately controlled pain (p = .041). Women who committed suicide had more prevalent chronic illnesses and were more likely to have been diagnosed with clinically significant depression or other psychiatric disorders (p = .023). Both groups were significantly less likely to be married (p < .001) and more likely to be divorced (p < .001) than US Census data would predict. CONCLUSIONS: The different vulnerabilities of older women who want to die and either commit suicide or seek assistance deserve continued careful research. Poorly controlled pain was a factor in seeking assistance in dying, and depression and psychiatric disorders characterized older women who committed suicide in our study. Not having a spouse may increase isolation and reinforce the hopelessness of women who are living with catastrophic illness.
Servera, E., J. Sancho, et al. (2003). "Non-invasive management of an acute chest infection for a patient with ALS." J Neurol Sci 209(1-2): 111-113. We describe a man diagnosed with non-bulbar amyotrophic lateral sclerosis (ALS) who uses 24-h non-invasive ventilator at home, and assisted cough through the use of the mechanical insufflation-exsufflation (MAC) device (CoughAssist, J.H. Emerson). This was essential for the removal of bronchial secretions in order to provide successful non-invasive management (and indeed less suffering for the patient) during an acute respiratory tract infection with hypoxemia and failure of manually assisted cough.
Shibata, M., K. Abe, et al. (2003). "Complex regional pain syndrome type I associated with amyotrophic lateral sclerosis." Clin J Pain 19(1): 69-70. BACKGROUND (CRPS I [formerly called reflex sympathetic dystrophy]) is a syndrome with pain and signs of autonomic dysfunction after trauma or immobilization; the pathophysiologic mechanisms of CRPS I, however, remain unknown.DESIGN The authors present a case of CRPS I associated with amyotrophic lateral sclerosis. Along with the motor paresis due to amyotrophic lateral sclerosis, pain, swelling, and signs of autonomic disturbance occurred.CONCLUSIONS This case supports the hypothesis that immobilization is one of the major contributing factors for CRPS I.
Shipp, E. L., F. Cantini, et al. (2003). "Dynamic Properties of the G93A Mutant of Copper-Zinc Superoxide Dismutase As Detected by NMR Spectroscopy: Implications for the Pathology of Familial Amyotrophic Lateral Sclerosis." Biochemistry 42(7): 1890-9. The backbone assignment of the copper-zinc superoxide dismutase amyotrophic lateral sclerosis G93A mutant was performed on an (15)N-enriched protein sample. (15)N R(1), R(2), and R(1)(rho) and (15)N-(1)H NOE experiments were then carried out at 600 MHz on G93A Cu(2)Zn(2)SOD and the values compared to the dynamics data for the "wild-type" protein. In addition, (15)N and (1)H chemical shift comparisons between wild-type Cu(2)Zn(2)SOD and its G93A mutant were also made. G93A exhibits a higher mobility than wild-type Cu(2)Zn(2)SOD, particularly in loops III and V, on a time scale faster than the rate of protein tumbling. There are also distinct chemical shift and NOE differences in residues 35-42 and 92-95, which comprise these loops. These two regions of Cu(2)Zn(2)SOD form the end of the beta-barrel termed the "beta-barrel plug" [Tainer, J. A., Getzoff, E. D., Beem, K. M., Richardson, J. S., and Richardson, D. C. (1982) J. Mol. Biol. 160, 181-217]. The increased mobility and reduction of the number of observed NOEs in this region indicate an opening of the beta-barrel that may lead to amyloid fibrillogenesis. Alternatively, a motor neuron-specific substrate may bind this region of the protein, leading to deleterious modifications and/or reactions.
Son, M., C. D. Cloyd, et al. (2003). "Aggregate formation in Cu,Zn superoxide dismutase related proteins." J Biol Chem. Aggregation of Cu,Zn superoxide dismutase (SOD1) protein is a pathologic hallmark of familial amyotrophic lateral sclerosis (ALS) linked to mutations in the SOD1 gene, although the structural motifs within mutant SOD1 that are responsible for its aggregation are unknown. Copper chaperone for SOD1 (CCS) and extracellular Cu,Zn superoxide dismutase (SOD3) have some sequence identity with SOD1, particularly in the regions of metal binding, but play no significant role in mutant SOD1 induced disease. We hypothesized that it would be possible to form CCS or SOD3 positive aggregates by making these molecules resemble mutant SOD1 via the introduction of point mutations in codons homologous to a disease causing G85R SOD1 mutation. Using an in vitro assay system, we found that expression of wild type human CCS or a modified intracellular wild type SOD3 does not result in significant aggregate formation. In contrast, expression of G168R CCS or G146R SOD3 produced aggregates as evidenced by the presence of high molecular weight protein complexes on Western gels or inclusion bodies on immunofluorescence. CCS and SOD3 positive inclusions appear to be ubiquitinated and localize to aggresomes. These results suggest that proteins sharing structural similarities to mutant SOD1 are also at risk for aggregate formation.
Strocchi, P., A. Pession, et al. (2003). "Up-regulation of cDK5/p35 by oxidative stress in human neuroblastoma IMR-32 cells." J Cell Biochem 88(4): 758-65. Cdk5, a member of the cyclin-dependent kinase (cdk) family, is predominately active in neurons, where its activity is tightly regulated by the binding of its neuronal activators p35 and p39. Cdk5 is implicated in regulating the proper neuronal function; a deregulation of cdk5 has been found associated with Alzheimer's disease and amyotrophic lateral sclerosis. As oxidative stress products have been seen co-localized with pathological hallmarks of neurodegenerative diseases, we studied the effect of oxidative stress on the cdk5 enzyme in human neuroblastoma IMR-32 cells. We evaluated the effects of 4-hydroxynonenal and Ascorbate plus FeSO(4) on cdk5 activity and on the expression of cdk5 and p35 proteins. We report here that oxidative stress stimulates cdk5 activity and induces an upregulation of its regulatory and catalytic subunit expression in IMR-32 vital cells, showing that the cdk5 enzyme is involved in the signaling pathway activated by oxidative stress.
Su, Z. Z., M. Leszczyniecka, et al. (2003). "Insights into glutamate transport regulation in human astrocytes: cloning of the promoter for excitatory amino acid transporter 2 (EAAT2)." Proc Natl Acad Sci U S A 100(4): 1955-60. Glutamate transport is central to neurotransmitter functions in the brain. Impaired glutamate transport induces neurotoxicity associated with numerous pathological processes, including stroke/ischemia, temporal lobe epilepsy, Alzheimer's disease, amyotrophic lateral sclerosis, Huntington's disease, HIV-1-associated dementia, and growth of malignant gliomas. Excitatory amino acid transporter-2 (EAAT2) is a major glutamate transporter in the brain expressed primarily in astrocytes. We presently describe the cloning and characterization of the human EAAT2 promoter, demonstrating elevated expression in astrocytes. Regulators of EAAT2 transport, both positive and negative, alter EAAT2 transcription, promoter activity, mRNA, and protein. These findings imply that transcriptional processes can regulate EAAT2 expression. Moreover, they raise the intriguing possibility that the EAAT2 promoter may be useful for targeting gene expression in the brain and for identifying molecules capable of modulating glutamate transport that could potentially inhibit, ameliorate, or prevent various neurodegenerative diseases.
Takamiya, R., M. Takahashi, et al. (2003). "Glycation proceeds faster in mutated Cu, Zn-superoxide dismutases related to familial amyotrophic lateral sclerosis." Faseb J. Amyotrophic lateral sclerosis (ALS) involves the progressive degeneration of motor neurons in the spinal cord and motor cortex. It has been shown that 15-20% of patients with familial ALS (FALS) have defects in the Sod1 gene that encodes Cu, Zn-superoxide dismutase (SOD). To elucidate the pathological role of mutated Cu, Zn-SODs in FALS, the susceptibility of mutants to glycation was examined. Mutated Cu, Zn-SODs (G37R, G93A, and I113T) related to FALS and wild type were produced in a baculovirus/insect cell expression system. Glycated and nonglycated proteins were separated on a boronate column, and the nonglycated fraction was then incubated with glucose. The mutated Cu, Zn-SODs were found to be highly susceptible to glycation compared with the wild-type enzyme as estimated by Western blot analysis using an anti-hexitol lysine antibody. The mutated Cu, Zn-SOD incubated with glucose generated higher levels of hydrogen peroxide than the wild-type enzyme. Mutated Cu, Zn-SODs were also shown to be highly susceptible to fructation, and the fructated mutant also produced higher levels of hydrogen peroxide than the wild type. These results suggest that high susceptibility of mutated Cu, Zn-SODs to glycation could be the origin of the oxidative stress associated with neuronal dysfunction in FALS.
Tiwari, A. and L. J. Hayward (2003). "Familial amyotrophic lateral sclerosis mutants of copper/zinc superoxide dismutase are susceptible to disulfide reduction." J Biol Chem 278(8): 5984-92. We observed that 14 biologically metallated mutants of copper/zinc superoxide dismutase (SOD1) associated with familial amyotrophic lateral sclerosis all exhibited aberrantly accelerated mobility during partially denaturing PAGE and increased sensitivity to proteolytic digestion compared with wild type SOD1. Decreased metal binding site occupancy and exposure to the disulfide-reducing agents dithiothreitol, Tris(2-carboxyethyl)phosphine (TCEP), or reduced glutathione increased the fraction of anomalously migrating mutant SOD1 proteins. Furthermore, the incubation of mutant SOD1s with TCEP increased the accessibility to iodoacetamide of cysteine residues that normally participate in the formation of the intrasubunit disulfide bond (Cys-57 to Cys-146) or are buried within the core of the beta-barrel (Cys-6). SOD1 enzymes in spinal cord lysates from G85R and G93A mutant but not wild type SOD1 transgenic mice also exhibited abnormal vulnerability to TCEP, which exposed normally inaccessible cysteine residues to modification by maleimide conjugated to polyethylene glycol. These results implicate SOD1 destabilization under cellular disulfide-reducing conditions at physiological pH and temperature as a shared property that may be relevant to amyotrophic lateral sclerosis mutant neurotoxicity.
Tobisawa, S., Y. Hozumi, et al. (2003). "Mutant SOD1 linked to familial amyotrophic lateral sclerosis, but not wild-type SOD1, induces ER stress in COS7 cells and transgenic mice." Biochem Biophys Res Commun 303(2): 496-503. Mutations in a Cu, Zn-superoxide dismutase (SOD1) cause motor neuron death in human familial amyotrophic lateral sclerosis (FALS) and its mouse model, suggesting that mutant SOD1 has a toxic effect on motor neurons. However, the question of how the toxic function is gained has not been answered. Here, we report that the mutant SOD1s linked to FALS, but not wild-type SOD1, aggregated in association with the endoplasmic reticulum (ER) and induced ER stress in the cDNA-transfected COS7 cells. These cells showed an aberrant intracellular localization of mitochondria and microtubules, which might lead to a functional disturbance of the cells. Motor neurons of the spinal cord in transgenic mice with a FALS-linked mutant SOD1 also showed a marked increase of GRP78/BiP, an ER-resident chaperone, just before the onset of motor symptoms. These data suggest that ER stress is involved in the pathogenesis of FALS with an SOD1 mutation.
Toyoshima, Y., Y. S. Piao, et al. (2003). "Pathological involvement of the motor neuron system and hippocampal formation in motor neuron disease-inclusion dementia." Acta Neuropathol (Berl). We report two patients with motor neuron disease-inclusion dementia, with special reference to the pathology of the motor neuron system and hippocampal formation. The ages of the patients at death were 55 and 62 years, and the disease durations were 8 and 3 years, respectively. The two patients exhibited progressive frontotemporal dementia in the absence of motor neuron signs. At autopsy, both cases exhibited frontotemporal lobar atrophy with ubiquitin-positive, and tau- and alpha-synuclein-negative neuronal inclusions. As expected from the clinical signs, in both cases, the upper and lower motor neuron systems were well preserved: no Bunina bodies or ubiquitinated inclusions were detected in the motor neurons. However, of great importance was that when visualized immunohistochemically, the Golgi apparatus and trans-Golgi network often exhibited fragmentation in the lower motor neurons (the spinal anterior horn cells). In one of the cases, a decrease in the amount of Golgi apparatus was also a frequent feature in the upper motor neurons (Betz cells in the motor cortex). Moreover, in both cases, circumscribed degeneration affecting the CA1-subiculum border zone was evident in the hippocampal formation. These findings further strengthen the idea that, pathologically, motor neuron disease-inclusion dementia is a rare phenotype of amyotrophic lateral sclerosis.
Trail, M., N. D. Nelson, et al. (2003). "A study comparing patients with amyotrophic lateral sclerosis and their caregivers on measures of quality of life, depression, and their attitudes toward treatment options." J Neurol Sci 209(1-2): 79-85. OBJECTIVE: To compare amyotrophic lateral sclerosis (ALS) patients and their caregivers on measures of quality of life (QOL), depression, and their attitudes toward treatment options. METHODS: Over a 14-month period, we analyzed responses from 27 ALS patients and 19 ALS caregivers as they arrived at the Department of Neurology, Baylor College of Medicine, Vicki Appel MDA, ALS Clinic, and those who completed the study measures. Patients were given the Appel ALS Rating Scale (AALS), the ALS Functional Rating Scale (ALSFRS), McGill Quality of Life Questionnaire Single-Item Scale (MQOL-SIS), and the Beck Depression Inventory-II (BDI-II). An internally generated scale of 1-7 was used to measure perception of emotional support, QOL for others (i.e., the patient's perception of the caregiver's QOL and the caregiver's perception of the patient's QOL), and experience of pain. Attitudes toward treatment options were assessed by yes/no/uncertain responses. Caregivers were administered all of the above measures except the AALS, ALSFRS, and pain scale. Percentage, mean, and standard deviation values were determined. Significance levels were also calculated. RESULTS: Twenty-seven patients with a mean age of 57.2 (range 34-81) years and nineteen caregivers with a mean age of 56.9 (range 28-82) years completed the study. The patients were of moderate disease severity with a mean AALS total score of 76.3 (range 39-134) and a mean ALSFRS score of 28.4 (range 12-40). The mean rating of QOL for patients was 5.9 and the mean rating of QOL for caregivers was 5.7 (range 1-7). The patients reported slightly less depression (9.8) than their caregivers (10.7) (range 0-63). There was, however, no significant difference between patients and caregivers on scores of QOL and depression. Patients tended to overestimate caregivers' QOL by a small degree, whereas caregivers tended to underestimate the patients' QOL by a greater degree. Over one-half of both groups would consider percutaneous esophageal gastrostomy (PEG) placement. Patient and caregiver responses to the use of BIPAP differed. Though over half of both groups endorsed the idea of future BIPAP use, more patients (41%) than caregivers (5%) were uncertain. Only 3% of patients responded negatively compared to 32% of caregivers. Both groups were only minimally interested in future invasive ventilation. DISCUSSION: Factors contributing to quality of life, depression, and attitudes toward treatment options need to be periodically explored with patients and caregivers throughout the course of the illness. Health care professionals should recognize that the needs and goals of the two groups might differ. For both patients and caregivers, health care professionals should provide education and opportunities for discussion centered on the issues followed by referrals and interventions appropriate to the situation.
Valentine, J. S. and P. J. Hart (2003). "Bioinorganic Chemistry Special Feature: Misfolded CuZnSOD and amyotrophic lateral sclerosis." Proc Natl Acad Sci U S A 100(7): 3617-22. Amyotrophic lateral sclerosis (ALS) is a progressive degenerative disease of motor neurons. The inherited form of the disease, familial ALS, represents 5-10% of the total cases, and the best documented of these are due to lesions in SOD1, the gene encoding copper-zinc superoxide dismutase (CuZnSOD). The mechanism by which mutations in SOD1 cause familial ALS is currently unknown. Two hypotheses have dominated recent discussion of the toxicity of ALS mutant CuZnSOD proteins: the oligomerization hypothesis and the oxidative damage hypothesis. The oligomerization hypothesis maintains that mutant CuZnSOD proteins are, or become, misfolded and consequently oligomerize into increasingly high-molecular-weight species that ultimately lead to the death of motor neurons. The oxidative damage hypothesis maintains that ALS mutant CuZnSOD proteins catalyze oxidative reactions that damage substrates critical for viability of the affected cells. This perspective reviews some of the properties of both wild-type and mutant CuZnSOD proteins, suggests how these properties may be relevant to these two hypotheses, and proposes that these two hypotheses are not necessarily mutually exclusive.
Van Den Berg-Vos, R. M., J. Visser, et al. (2003). "Sporadic lower motor neuron disease with adult onset: classification of subtypes." Brain 126(Pt 5): 1036-1047. The discovery of the genetic basis of hereditary lower motor neuron disease (LMND) and the recognition of multifocal motor neuropathy as a distinct clinical entity necessitate a new classification of LMND. To this end, we studied the clinical and electrophysiological features of 49 patients with sporadic adult-onset LMND in a cross-sectional study. Disease duration was more than 4 years to exclude the majority of patients with amyotrophic lateral sclerosis. Based on the pattern of weakness, we identified three groups: 13 patients with generalized weakness (group 1); eight patients with symmetrical, distal muscle weakness (group 2); and 28 patients with non-generalized asymmetrical weakness of the arms in most patients (group 3). Group 3 could be subdivided into patients with weakness in predominantly the distal (group 3a) or the proximal (group 3b) muscle groups, both with disease progression to adjacent spinal cord segments. Distinctive features of group 1 were an older age at onset, more severe weakness and muscle atrophy, lower reflexes, greater functional impairment, more widespread abnormalities on concentric needle EMG, respiratory insufficiency and serum M-protein. In groups 2 and 3, concentric needle EMG findings also suggested a more widespread disease process. Retrospectively, the prognosis of sporadic adult-onset LMND appears to be favourable, because clinical abnormalities were still confined to one limb in most patients after a median disease duration of 12 years. We propose to classify the patients in the different subgroups as slowly progressive spinal muscular atrophy (group 1), distal spinal muscular atrophy (group 2), segmental distal spinal muscular atrophy (group 3a) and segmental proximal spinal muscular atrophy (group 3b). The described clinical phenotypes may help to distinguish between different LMND forms.
Wada, M., S. Ono, et al. (2003). "Decreased galectin-1 immunoreactivity of the skin in amyotrophic lateral sclerosis." J Neurol Sci 208(1-2): 67-70. Amyotrophic lateral sclerosis (ALS) is a fatal neurodegenerative disease involving motor neurons. In addition to motor neuron signs and symptoms, a lack of bedsores has been considered a feature of ALS. Recently, we revealed that galectin-1 is a component of the axonal spheroid, which is an early pathological change of the spinal cord in ALS. To investigate whether galectin-1 is associated with skin changes in ALS, we performed an immunohistochemical investigation using anti-galectin-1 antibodies. The present study revealed that galectin-1 immunoreactivity is reduced in the skin of patients with ALS, suggesting that cutaneous galectin-1 is involved in the pathological process of ALS.
Waldmeier, P. C. (2003). "Prospects for antiapoptotic drug therapy of neurodegenerative diseases." Prog Neuropsychopharmacol Biol Psychiatry 27(2): 303-21. The evidence for a role of apoptosis in the neurodegenerative diseases, Alzheimer's disease (AD), Parkinson's disease (PD) and amyotrophic lateral sclerosis (ALS), and in the more acute conditions of cerebral ischemia, traumatic brain injury (TBI), and spinal cord injury (SCI) is reviewed with regard to potential intervention by means of small antiapoptotic molecules. In addition, the available animal models for these diseases are discussed with respect to their relevance for testing small antiapoptotic molecules in the context of what is known about the apoptotic pathways involved in the diseases and the models. The principal issues related to pharmacotherapy by apoptosis inhibition, i.e., functionality of rescued neurons and potential interference with physiologically occurring apoptosis, are pointed out. Finally, the properties of a number of small antiapoptotic molecules currently under clinical investigation are summarized.It is concluded that the evidence for a role of apoptosis at present is more convincing for PD and ALS than for AD. In PD, damage to dopaminergic neurons may occur through oxidative stress and/or mitochondrial impairment and culminate in activation of an apoptotic, presumably p53-dependent cascade; some neurons experiencing energy failure may not be able to complete apoptosis, end up in necrosis and give rise to inflammatory processes. These events are reasonably well reflected in some of the PD animal models, notably those involving 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) and rotenone. In sporadic ALS, an involvement of pathways involving p53 and Bcl-2 family members appears possible if not likely, but is not established. The issue is important for the development of antiapoptotic compounds for the treatment of this disease because of differential involvement of p53 in different mutant superoxide dismutase (SOD) mice. Most debated is the role of apoptosis in AD; this implies that little is known about potentially involved pathways. Moreover, there is a lack of suitable animal models for compound evaluation.Apoptosis or related phenomena are likely involved in secondary cell death in cerebral ischemia, TBI, and SCI. Most of the pertinent information comes from animal experiments, which have provided some evidence for prevention of cell death by antiapoptotic treatments, but little for functional benefit. Much remains to be done in this area to explore the potential of antiapoptotic drugs.There is a small number of antiapoptotic compounds in clinical development. With some of them, evidence for maintenance of functionality of the rescued neurons has been obtained in some animal models, and the fact that they made it to phase II studies in patients suggests that interference with physiological apoptosis is not an obligatory problem. The prospect that small antiapoptotic molecules will have an impact on the therapy of neurodegenerative diseases, and perhaps also of ischemia and trauma, is therefore judged cautiously positively.
Weishaupt, J. H., C. Neusch, et al. (2003). "Cyclin-dependent kinase 5 (CDK5) and neuronal cell death." Cell Tissue Res. Many neurological disorders like Parkinson's and Alzheimer's disease, amyotrophic lateral sclerosis (ALS) or stroke have in common a definite loss of CNS neurons due to apoptotic or necrotic neuronal cell death. Previous studies suggested that proapoptotic stimuli may trigger an abortive and, therefore, eventually fatal cell cycle reentry in postmitotic neurons. Neuroprotective effects of small molecule inhibitors of cyclin-dependent kinases (CDKs), which are key regulators of cell cycle progression, support the cell cycle theory of neuronal apoptosis. However, growing evidence suggests that deregulated CDK5, which is not involved in cell cycle control, rather than cell cycle relevant members of the CDK family, promotes neuronal cell death. Here we summarize the current knowledge about the involvement of CDK5 in neuronal cell death and discuss possible up- or downstream partners of CDK5. Moreover, we discuss potential therapeutic options that might arise from the identification of CDK5 as an important upstream element of neuronal cell death cascades.
Wickelgren, I. (2003). "Neuroscience. Power to the paralyzed." Science 299(5606): 497.
Wilczak, N., R. A. de Vos, et al. (2003). "Free insulin-like growth factor (IGF)-I and IGF binding proteins 2, 5, and 6 in spinal motor neurons in amyotrophic lateral sclerosis." Lancet 361(9362): 1007-11. BACKGROUND: Insulin-like growth factor-I (IGF-I) is a potent survival factor for motor neurons and is being investigated as possible therapeutic agent for amyotrophic lateral sclerosis. However, very little information is available on the components of the IGF-I system in this disease. Insulin-like growth factor binding proteins (IGFBPs) play an important part in regulating the bioavailability of IGF-I. METHODS: We investigated the components of the IGF-I system in spinal cord sections of ten patients with amyotrophic lateral sclerosis and in ten controls without neurological disease. IGF-I was studied by western immunoblotting. IGFBPs and IGF-I receptors were investigated by immunohistochemistry and Western immunoblotting. FINDINGS: Total IGF-I in ventral horn homogenates did not differ between patients and controls. However, free IGF-I was 53% lower in patients than in controls. Compared with controls, immunoreactivity in the spinal motor neurons of patients with amyotrophic lateral sclerosis was 64% higher for IGFBP2, 46% higher for IGFBP5, and 33% higher for IGFBP6, with upregulation of IGF-I receptors. Immunoreactivity for IGFBPs1, 3, and 4 did not differ between patients and controls. INTERPRETATION: In the ventral horns of patients, free IGF-I is reduced, which could be because of specific increases in IGFBPs 2, 5, and 6 in spinal motor neurons. This abnormality might have an important role in the processes leading to motor neuron death, and should be taken into account when developing treatments aimed to stimulate IGF-I receptors in motor neurons.
Windisch, W., K. Freidel, et al. (2003). "Evaluation of health-related quality of life using the MOS 36-Item Short-Form Health Status Survey in patients receiving noninvasive positive pressure ventilation." Intensive Care Med. OBJECTIVE. To collect benchmark data on the MOS 36-Item Short-Form Health Status Survey (SF-36) in patients receiving noninvasive positive pressure ventilation and to examine whether health-related quality of life is influenced by the underlying disease or by physical parameters. DESIGN AND SETTING. Multicentric clinical cross-sectional trial in four general wards specialized in noninvasive positive pressure ventilation. PATIENTS AND PARTICIPANTS. 226 patients (78 chronic obstructive pulmonary disease, 57 kyphoscoliosis, 20 posttuberculosis sequelae, 17 Duchenne muscular dystrophy, 13 polyneuropathy, 13 myopathy, 6 amyotrophic lateral sclerosis, 12 obesity-hypoventilation syndrome, 4 poliomyelitis sequelae, 3 phrenic nerve lesion, 3 central hypoventilation syndrome) who used noninvasive positive pressure ventilation for home mechanical ventilation. MEASUREMENTS AND RESULTS. Health-related quality of life as assessed by the SF-36 was lower than in the general population. Overall the Physical Component Summary (PCS) was significantly lower than the general population norm; the Mental Component Summary (MCS) was also reduced but less markedly. Patients with chronic obstructive pulmonary disease were more impaired in MCS than those with kyphoscoliosis. PCS was significantly associated with age. Gender, lung function, and arterial blood gas values were not significant predictors of health-related quality of life. CONCLUSIONS. Benchmark SF-36 data in patients receiving noninvasive positive pressure ventilation are given. Although physical health is significantly impaired in these patients, this does not necessarily lead to mental limitation, and mental health is influenced by the underlying disease, but not by physical parameters.
Wu, S. N. (2003). "Large-conductance ca(2+)-activated k(+) channels:physiological role and pharmacology." Curr Med Chem 10(8): 649-61. Large-conductance Ca(2+)-activated K(+) (BK(Ca)) channels differ from most of other K(+) channels in that their activation is under dual control, i.e., activated by either increase in intracellular Ca(2+) or membrane depolarization. These channels, which are widely distributed in a variety of cells, can control Ca(2+) influx as well as a number of Ca(2+)-dependent physiological processes. In neurons or neuroendocrine cells, BK(Ca) channels are believed to play an important role in controlling hormonal secretion by altering the duration and frequency of action potentials. The activity of BK(Ca) channels functionally expressed in vascular endothelial cells can control K(+) efflux and affect intracellular Ca(2+) concentration. Experimental observations have revealed that a variety of compounds can directly modulate BK(Ca) channel activity. Epoxyeicosatrienoic acids, a metabolite of arachidonic acid, and the increase in intracellular cyclic GMP with vinpocetine or YC-1 can stimulate BK(Ca) channel activity. The increased activity of BK(Ca) channels thus serves as a negative feedback mechanism to limit Ca(2+) influx in excitable cells. Clotrimazole, an imidazole P-450 inhibitor used for the management of sickle cell anemia, can directly suppress BK(Ca) channel activity. Riluzole, a drug used for the treatment of amyotrophic lateral sclerosis, can directly enhance channel activity in neuroendocrine cells. This effect may explain its inhibitory action on excitatory neurotransmission. 2-Methoxyestradil, an endogenous metabolite of 17beta-estradiol, suppresses BK(Ca) channel activity, whereas resveratrol, a natural phytoalexin present in grapes and wine, directly stimulates BK(Ca) channel activity in vascular endothelial cells. These effects may be responsible for their actions on functional activities of endothelial cells. The fenamates, a family of nonsteroidal anti-inflammatory drugs, are also openers of BK(Ca) channels. Therefore, the modulation of BK(Ca) channel activity in excitable and non-excitable cells can be important for therapeutic interventions.
Wu, A. S., M. Kiaei, et al. (2003). "Iron porphyrin treatment extends survival in a transgenic animal model of amyotrophic lateral sclerosis." J Neurochem 85(1): 142-150. Oxidative damage, produced by mutant Cu/Zn superoxide dismutase (SOD1), may play a role in the pathogenesis of amyotrophic lateral sclerosis (ALS), a devastating motor neuron degenerative disease. A novel approach to antioxidant therapy is the use of metalloporphyrins that catalytically scavenge a wide range of reactive oxygen and reactive nitrogen species. In this study, we examined the therapeutic potential of iron porphyrin (FeTCPP) in the G93A mutant SOD1 transgenic mouse model of ALS. We found that intraperitoneal injection of FeTCPP significantly improved motor function and extended survival in G93A mice. Similar results were seen with a second group of mice wherein treatment with FeTCPP was initiated at the onset of hindlimb weakness-roughly equivalent to the time at which treatment would begin in human patients. FeTCPP-treated mice also showed a significant reduction in levels of malondialdehyde (a marker of lipid peroxidation), in total content of protein carbonyls (a marker of protein oxidation), and increased neuronal survival in the spinal cord. These results therefore provide further evidence of oxidative damage in a mouse model of ALS, and suggest that FeTCPP could be beneficial for the treatment of ALS patients.
Zhang, W., M. Narayanan, et al. (2003). "Additive neuroprotective effects of minocycline with creatine in a mouse model of ALS." Ann Neurol 53(2): 267-70. The known neuroprotective effects of minocycline and creatine in animal models of amyotrophic lateral sclerosis (ALS) led us to examine whether the combination of these agents would result in increased neuroprotection. As previously reported, we confirmed in ALS mice that either minocycline or creatine treatment results in improvement in motor performance and extended survival. We report that combination of minocycline and creatine resulted in additive neuroprotection, suggesting this to be a novel potential strategy for the treatment of ALS. To our knowledge, this is the first report demonstrating additive neuroprotection of a combinatorial approach in a mouse model of ALS. Adding relevancy to our findings, minocycline and creatine, are relatively safe, cross the blood-brain barrier, and are currently available for human evaluation.
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