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Bandopadhyay, R., R. de Silva, et al. (2001). "No pathogenic
mutations in the synphilin-1 gene in Parkinson's disease." Neurosci Lett
307(2): 125-7.
alpha-Synuclein is mutated in rare autosomal dominant forms of Parkinson's
disease and is a major component of Lewy bodies and neurites. Synphilin-1, a
novel protein interacts in vivo and co-localises with alpha-synuclein in Lewy
bodies. We analysed the synphilin-1 gene in familial Parkinson's disease by
single-strand conformation polymorphism (SSCP) and automated sequencing but
found no coding mutations. However, we identified two novel intronic
polymorphisms; an A/T polymorphism in intron 2, resulting in the introduction of
an Alu1 site and a second G/T polymorphism in intron 4. We analysed the intron 2
polymorphism for allelic association as it was conducive to rapid screening but
observed no changes in frequency between Parkinson's disease cases and controls.
Barbieri, S., K. Hofele, et al. (2001). "Mouse models of alpha-synucleinopathy
and Lewy pathology. Alpha-synuclein expression in transgenic mice." Adv Exp
Med Biol 487: 147-67.
Bauer, M., M. Meyer, et al. (2001). "Liposome-mediated gene transfer to fetal
human ventral mesencephalic explant cultures." Neurosci Lett 308(3):
169-72.
The feasibility of non-viral gene transfer using liposomes is described for
human fetal nigral tissue. Ventral mesencephalic explants from 6 to 12 week old
fetuses were grown as free-floating roller tube cultures. For the transfection,
a vector coding for beta-galactosidase driven by the Rous Sarcoma Virus promoter
was used. The developmental stage of the human tissue, time in vitro and the
amount of vector DNA used significantly influenced the transfection efficiency.
Optimal transfection results were obtained with tissue from a 10 week old fetus,
cultured for 4 days and transfected with mixtures containing 4 microg vector
DNA. Histological analysis suggested that a specific population of ventral
mesencephalic precursor cells were the target for the gene transfer. This
finding might have implications for gene delivery and cell replacement
strategies in Parkinson's disease.
Beal, M. F. (2001). "Experimental models of Parkinson's disease." Nat Rev
Neurosci 2(5): 325-34.
Research into the pathogenesis of Parkinson's disease has been rapidly advanced
by the development of animal models. Initial models were developed by using
toxins that specifically targeted dopamine neurons, the most successful of which
used 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine, a toxin that causes
parkinsonism in man. More recently, the identification of alpha-synuclein
mutations as a rare cause of Parkinson's disease has led to the development of
alpha-synuclein transgenic mice and Drosophila. Here, I discuss the merits and
limitations of these different animal models in our attempts to understand the
physiology of Parkinson's disease and to develop new therapies.
Beal, M. F. and P. Hantraye (2001). "Novel therapies in the search for a cure
for Huntington's disease." Proc Natl Acad Sci U S A 98(1): 3-4.
Begley, S. (2001). "IV. Genes, cells, drugs. Cures for the future. Fountains of
youth." Newsweek 138(11A): 84-6.
Behari, M., A. K. Srivastava, et al. (2001). "Risk factors of Parkinson's
disease in Indian patients." J Neurol Sci 190(1-2): 49-55.
Epidemiological data on risk factors of Parkinson's disease (PD) are not
available from India. In a case control study, we investigated environmental and
genetic risk factors in the etiology of idiopathic Parkinson's disease. Three
hundred seventy-seven patients of Parkinson disease (301 men, 76 women,
mean+/-SD age 56.78+/-11.08 years) and equal number of age matched (+/-3 years)
neurological controls (271 men, 106 women, mean+/-SD age 56.62+/-11.17 years)
were included in the study. Conditional logistic regression model was used to
determine the risk factors of PD. We found that male gender, family history of
Parkinson's disease, past history of depression of up to 10-year duration and
well water drinking of more than 10-year duration were significantly associated
with occurrence of Parkinson's disease, whereas tobacco smoking of up to 20-year
duration and exposure to pets had protective effect. However, tobacco smoking of
more than 20-year duration, well water drinking of up to 10-year duration,
vegetarian dietary habit, occupation involving physical exertion, rural living,
farming, exposure to insecticides, herbicides, rodenticides, alcohol intake and
family history of neurodegenerative diseases had no significant correlation with
occurrence of PD in the patient population studied. Results of our study support
the hypothesis of multifactorial etiology of PD with environmental factors
acting on a genetically susceptible host.
Berciano, J. (2001). "[Genetics in Parkinson's disease: toward a new nosological
era]." Med Clin (Barc) 116(16): 614-6.
Bertoni, J. M., J. L. Prendes, et al. (2001). "Long-term Medical Treatment for
Parkinson's Disease." Curr Treat Options Neurol 3(6): 495-506.
The authors of this paper view Parkinson's disease (PD) as a clinically defined
progressive syndrome of resting limb tremor, bradykinesia, muscle rigidity, and
a shuffling unsteady gait that responds well to dopaminergic medications.
Parkinson's disease is a not a single entity, but rather a syndrome with diverse
causes, with both genetic and environmental risk factors. The clinician's
concern is to rule out other entities, especially those having another specific
treatment, and to give PD patients the best short- and long-term benefit, with
the least possible unwanted side effects.
Bezard, E., P. Ravenscroft, et al. (2001). "Upregulation of striatal
preproenkephalin gene expression occurs before the appearance of parkinsonian
signs in 1-methyl-4-phenyl- 1,2,3,6-tetrahydropyridine monkeys." Neurobiol
Dis 8(2): 343-50.
GABA and enkephalin-utilizing efferents from the striatum to the external
segment of the pallidal complex (GPe) are thought to be overactive in
Parkinson's disease (PD). This overactivity is generally held to play a major
role in the genesis of parkinsonian symptoms, which are thought to appear when
dopaminergic neuronal death exceeds a critical threshold. Little is known,
however, regarding the activity of this pathway during disease progression and
more particularly, prior to the emergence of parkinsonian symptoms. In order to
test the hypothesis that an upregulation of striatal preproenkephalin-A (PPE-A)
mRNA levels occurs before the appearance of parkinsonian motor disabilities, the
present study assessed PPE-A mRNA expression and striatal dopamine (DA) content
following a chronic 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP)
administration protocol in monkeys that produces a progressive parkinsonian
state. Groups ranged from normal to full parkinsonian through asymptomatic
lesioned monkeys. The key finding of this study is that PPE-A expression is
already upregulated in asymptomatic-lesioned monkeys showing a marked DA
depletion (56%). Importantly, this up-regulation is restricted to motor regions
of the basal ganglia circuitry. The increased PPE-A mRNA expression observed in
asymptomatic, but DA-depleted animals, supports our initial hypothesis of such
an upregulation occurring before the appearance of parkinsonian motor
disabilities. Furthermore, when considered with recent electrophysiological and
histochemical data, these findings question the functional significance of
upregulated enkephalin transmission in the indirect striatopallidal pathway.
Copyright 2001 Academic Press.
Blair, E., C. Redwood, et al. (2001). "Mutations in the gamma(2) subunit of
AMP-activated protein kinase cause familial hypertrophic cardiomyopathy:
evidence for the central role of energy compromise in disease pathogenesis."
Hum Mol Genet 10(11): 1215-20.
Familial hypertrophic cardiomyopathy (HCM) has been widely studied as a genetic
model of cardiac hypertrophy and sudden cardiac death. HCM has been defined as a
disease of the cardiac sarcomere, but mutations in the known contractile protein
disease genes are not found in up to one-third of cases. Further, no consistent
changes in contractile properties are shared by these mutant proteins, implying
that an abnormality of force generation may not be the underlying mechanism of
disease. Instead, all of the sarcomeric mutations appear to result in
inefficient use of ATP, suggesting that an inability to maintain normal ATP
levels may be the central abnormality. To test this hypothesis we have examined
candidate genes involved in energy homeostasis in the heart. We now describe
mutations in PRKAG2, encoding the gamma(2) subunit of AMP-activated protein
kinase (AMPK), in two families with severe HCM and aberrant conduction from
atria to ventricles in some affected individuals (pre-excitation or
Wolff-Parkinson-White syndrome). The mutations, one missense and one in-frame
single codon insertion, occur in highly conserved regions. Because AMPK provides
a central sensing mechanism that protects cells from exhaustion of ATP supplies,
we propose that these data substantiate energy compromise as a unifying
pathogenic mechanism in all forms of HCM. This conclusion should radically
redirect thinking about this disorder and also, by establishing energy depletion
as a cause of myocardial dysfunction, should be relevant to the acquired forms
of heart muscle disease that HCM models.
Bonifati, V., G. De Michele, et al. (2001). "The parkin gene and its phenotype.
Italian PD Genetics Study Group, French PD Genetics Study Group and the European
Consortium on Genetic Susceptibility in Parkinson's Disease." Neurol Sci
22(1): 51-2.
Mutations of the parkin gene on chromosome 6 cause autosomal recessive, early
onset parkinsonism. This is the most frequent form of monogenic parkinsonism so
far identified. The associated phenotypical spectrum encompasses early onset,
levodopa-responsive parkinsonism (average onset in the early 30s in Europe), and
it overlaps with dopa-responsive dystonia in cases with the earliest onset, and
with clinically typical Parkinson's disease in cases with later onset. Despite
clinical features, Lewy bodies are not found at autopsy in brains of patients
with parkin mutations. The parkin protein possesses ubiquitin ligase activity,
which is abolished by the pathogenic mutations.
Bonifati, V. (2001). "Monogenic Parkinsonisms and the genetics of Parkinson's
disease." Funct Neurol 16(1): 35-44.
Bonini, N. M. (2001). "Drosophila as a genetic approach to human
neurodegenerative disease." 7(3): 171-175.
Polyglutamine disease is a class of human neurodegenerative diseases
characterized by late-onset, progressive neural degeneration. The molecular
mechanism is expansion, within the coding region of the respective genes, of a
CAG repeat encoding glutamine. The expanded polyglutamine domain confers
dominant toxicity on the disease protein, leading to neuronal dysfunction and
degeneration. In order to develop Drosophila as a model system to approach and
study such human diseases, a human gene encoding an expanded polyglutamine
protein was introduced into the fly. Expression of this protein with a
pathogenic polyglutamine domain causes late-onset, progressive degeneration of
cells in the fly, as it does in humans with disease and mouse transgenic models.
Moreover, the protein shows abnormal protein aggregation in flies, similar to
human disease tissue. These studies indicate that molecular mechanisms of
polyglutamine-induced neurodegeneration are conserved in Drosophila. Through
these studies and additional studies to develop fly models for other human
neurodegenerative diseases, including Parkinson's disease, the power of
Drosophila genetics can be brought to bear toward the molecular understanding
and treatment of human neurodegeneration.
Bostantjopoulou, S., Z. Katsarou, et al. (2001). "Clinical features of
parkinsonian patients with the alpha-synuclein (G209A) mutation." Mov Disord
16(6): 1007-1013.
The motor and neuropsychological abnormalities in eight Greek patients with
Parkinson's disease (PD) carrying the alpha-synuclein gene mutation (G209A) were
studied. These patients (five men, three women) belonged to six different
families. Their symptoms started between 32-50 years of age (mean +/- SD, 39.7
+/- 7.6 years) and they had a mean disease duration of 5.4 +/- 2.1 years (range,
2-9 years) at the time of examination. Rigidity and bradykinesia predominated
both at disease onset as well as in the later stages and rest tremor was
relatively uncommon. Neuropsychological assessment showed that one patient was
mildly demented while another had impairment in memory, visuoconstructive
abilities, and executive function. Depression was present in only one patient.
Our findings indicate that genetic forms of parkinsonism share common motor and
cognitive characteristics with sporadic PD but raise the possibility that
greater cognitive impairment and the relative rarity of tremor may be
distinctive features worthy of further investigation. Copyright 2001 Movement
Disorder Society.
Boulu, R. G., C. Mesenge, et al. (2001). "[Neuronal death: potential role of the
nuclear enzyme, poly (ADP-ribose) polymerase]." Bull Acad Natl Med 185(3):
555-63; discussion 564-5.
Poly(ADP-ribose) polymerase (PARP, EC 2.4.2.30) is known as a nuclear enzyme
that is activated by DNA strand breaks to participate in DNA repair. It is also
called poly(ADP-ribose) synthase (PARS) or poly(ADP-ribose) transferase (PADRT).
In physiological conditions, PARP plays an important role in maintaining genomic
stability. However, for several pathological situations, which include massive
DNA injury (brain ischemia for example), excessive activation of PARP can
deplete stores of nicotinamide adenine dinucleotide (NAD+), the PARP substrate,
which, with the subsequent ATP depletion, leads to cell death. PARP activation
appears to play a major role in neuronal death induced by cerebral ischemia,
traumatic brain injury, Parkinson disease and other pathologies. PARP inhibitors
(3-aminobenzamide and other compounds) and PARP gene deletion induced dramatic
neuroprotection in experimental animals (rats, mice). Accordingly, these data
suggest that PARP inhibitors could provide a novel therapeutic approach in a
wide range of neurodegenerative disorders including cerebral ischemia and
traumatic brain injury.
Brattstrom, L. (2001). "Plasma homocysteine and MTHFR C677T genotype in levodopa-treated
patients with PD." Neurology 56(2): 281; discussion 281-2.
Brevig, T., M. Meyer, et al. (2001). "Xenotransplantation for brain repair:
reduction of porcine donor tissue immunogenicity by treatment with anti-Gal
antibodies and complement." Transplantation 72(2): 190-6.
BACKGROUND: Transplantation of embryonic neural tissue is a potential treatment
for Parkinson's disease. Because human donor material is in short supply,
porcine xenografts are considered a useful alternative. Current
immunosuppressive therapies fail, however, to protect intracerebral neural
xenografts from host CD4 T lymphocytes. To reduce the immunogenicity of porcine
donor tissue, we attempted to remove microglial cells with antibodies against
the alpha-galactosyl epitope (Galalpha1,3Galbeta1,4GlcNAc-R), or anti-Gal, and
complement, and studied whether this pretreatment can reduce direct and indirect
T-cell responses to the tissue. METHODS: Brain tissue from 27-day-old pig
embryos was dissociated and treated with human anti-Gal and rabbit complement.
The microglial content was analyzed by flow cytometry. [3H]thymidine
incorporation in cocultures of the brain cells and purified human CD4 T cells
was used to determine direct T-cell responses. Indirect T-cell responses were
studied by grafting pretreated and control-pretreated (no anti-Gal) nigral
tissue into the lesioned striatum of immunocompetent rats with
6-hydroxydopamine-induced hemiparkinsonism. Amphetamine-induced circling
behavior was used to measure graft function. RESULTS: Anti-Gal and complement
reduced the microglial content to 11-24% of control and abolished the ability of
the brain cells to induce human CD4 T-cell proliferation. Pretreated nigral
tissue reduced hemiparkinsonism by more than 50% in five of eight rats at some
point during the 10-week follow-up. Rats receiving control-pretreated nigral
tissue did not display this degree of improvement. CONCLUSIONS: Pretreatment
with anti-Gal and complement can reduce the immunogenicity of porcine neural
tissue, and might, therefore, be a valuable alternative or supplement to
immunosuppression in neural xenotransplantation.
Brooksbank, C. (2001). "Protein degradation: Parkin finds a partner and a
victim." Nat Rev Mol Cell Biol 2(1): 4-5.
Buervenich, S., F. Xiang, et al. (2001). "Identification of four novel
polymorphisms in the calcitonin/alpha-CGRP (CALCA) gene and an investigation of
their possible associations with Parkinson disease, schizophrenia, and manic
depression." Hum Mutat 17(5): 435-6.
We identified novel polymorphisms in the calcitonin/CGRPalpha (CALCA) gene by
direct sequencing of genomic DNA and subsequent genotyping by RFLP (restriction
fragment length polymorphism) detection and investigated association with
neurological or psychiatric disease. Four novel polymorphic alleles were found:
two (g.979G>A and g.4218T>C) represented single nucleotide polymorphisms (SNPs),
one consisted of two coupled SNPs in close vicinity to each other (g.1210T>C and
g.1214C>G), and one was an intronic 16-bp microdeletion (2919-2934del16). One of
the SNPs (g.4218T>C) causes a non-synonymous amino acid change (Leu66Pro) in the
third exon, an exon common to both procalcitonin and pro-alpha-CGRP. In a
subsequent association study, frequencies of the identified polymorphisms in
Parkinson and schizophrenia patients were compared with frequencies in the
normal population. No statistically significant association was found in our
material. The 16-bp microdeletion polymorphism was present in a family with
multiple cases of unipolar or bipolar depressive disorder. Using this
polymorphism as marker, cosegregation with the phenotype was observed in the
majority of individuals. Copyright 2001 Wiley-Liss, Inc.
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