Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0030567 (Parkinson's disease)
 63,064 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

In reactive gliosis, astrocytes undergo morphological and biochemical changes which can be mimicked in vitro by treatment with bFGF (basic fibroblast growth factor) or cAMP. To investigate the influence of activated cortical astrocytes on central nervous system (CNSD) neurons, we studied the effect of the supernatant from bFGF-treated astrocytes on the development of dopaminergic neurons from rat mesencephalon. Conditioned medium of untreated astrocytes stimulated dopamine uptake of mesencephalic cultures. After activation of astrocytes with bFGF this effect was greatly enhanced. It was significantly more potent than stimulating effects of other neurotrophic factors. The supernatant of these astrocytes increased the biochemical differentiation but not the survival of dopaminergic neurons in our cell culture system. Trypsin digestion and gel chromatography revealed that the activity was due to one or several proteins with molecular mass above 5 kDa. We excluded the participation of several factors known to be produced by astrocytes or that are neurotrophic for substantia nigra cultures. In particular, we provide evidence that bFGF, BDNF, NT-3, Il-1, Il-6, S100 beta and alpha 2-macroglobulin were not involved in the effect of the conditioned medium. In vitro stimulation of astrocytes therefore triggers the expression of currently uncharacterized factors which influence the biochemical differentiation of mesencephalic dopaminergic neurons, the cells that degenerate in Parkinson's disease.
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PMID:Cortical astrocytes activated by basic fibroblast growth factor secrete molecules that stimulate differentiation of mesencephalic dopaminergic neurons. 127 4

Nerve growth factor (NGF) is a member of an expanding family of neurotrophic factors (including brain-derived neurotrophic factor and the neurotrophins) that control the development and survival of certain neuronal populations both in the peripheral and in the central nervous systems. Its biological effects are mediated by a high-affinity ligand-receptor interaction and a tyrosine kinase signalling pathway. A potential use for NGF and its relatives in the treatment of neurological disorders such as Alzheimer's disease and Parkinson's disease requires an understanding of the structure-function relationships of NGF. NGF is a dimeric molecule, with 118 amino acids per protomer. We report the crystal structure of the murine NGF dimer at 2.3-A resolution, which reveals a novel protomer structure consisting of three antiparallel pairs of beta strands, together forming a flat surface. Two subunits associate through this surface, thus burying a total of 2,332 A. Four loop regions, which contain many of the variable residues observed between different NGF-related molecules, may determine the different receptor specificities. A clustering of positively charged side chains may provide a complementary interaction with the acidic low-affinity NGF receptor. The structure provides a model for rational design of analogues of NGF and its relatives and for testing the NGF-receptor recognition determinants critical for signal transduction.
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PMID:New protein fold revealed by a 2.3-A resolution crystal structure of nerve growth factor. 195 7

In 1979, we presented the first evidence that grafts of fetal brain tissue to the adult central nervous system could counteract an experimentally induced neurological deficit. Using the unilaterally dopamine-denervated rat model of Parkinson's disease, it was first shown that fetal substantia nigra grafts were effective and, later, that adult adrenal medullary chromaffin tissue might be used as a possible substitute for fetal brain tissue. These observations led to the first clinical trials with chromaffin autografting in severe cases of Parkinson's disease, which were initiated at the Karolinska Hospital in 1982, and several years later to clinical trials with grafts of fetal dopamine neuroblasts obtained after early elective abortions. In parallel with the ongoing intense basic research aimed at optimizing grafting procedures and finding new possible clinical applications, there are now worldwide clinical trials of grafting procedures involving a large number of neurosurgical centers and a large number of patients. Here, I shall review our recent studies of grafts and growth factors as they relate to possible new therapeutic principles applicable not only to Parkinson's disease, but also to Alzheimer's senile dementia and possibly to spinal cord injury and other afflictions. Recent evidence suggests that cholinergic neurons in the brain, known to degenerate in Alzheimer's disease, depend on nerve growth factor. In one approach we have grafted genetically modified cell lines, designed to secrete large amounts of nerve growth factor, and demonstrated that they can rescue lesioned cholinergic neurons that would otherwise die. Nerve growth factor can also serve to enhance survival of, and promote fiber formation by, chromaffin grafts in experimental parkinsonism. Interestingly, a series of other growth factors, such as IGF-1, bFGF, aFGF, BDNF, TGF's, as well as their receptors, are now being cloned and in several cases shown to have interesting temporal and regional distributions as well as effects in the central nervous system. Our own studies using intraocular grafts suggest potent effects on fetal brain tissue growth of truncated IGF-1, bFGF, and aFGF. It thus appears as if neurosurgery is on the verge of entering a new era in which repair in the adult brain and spinal cord, once thought impossible in mammals, will become possible using growth factors and grafts.
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PMID:Grafts and growth factors in CNS. Basic science with clinical promise. 208 Mar 39

The pattern of retrogradely transported BDNF, a member of the nerve growth family of neurotrophins, following intrastriatal infusion was immunohistochemically visualized within the rodent central nervous system. Human recombinant BDNF was infused at a rate of 3 micrograms/h for 7 days with an Alzet 2002 minipump prior to sacrifice. Tissue immunohistochemically processed using a turkey anti-BDNF antibody revealed retrogradely transported BNDF within neurons located mainly within the ipsilateral frontoparietal cortex (predominantly layer V), parafascicular and posterior thalamic nuclei, and substantia nigra, pars compacta. Sections dual immunoreacted for BNNF and tyrosine hydroxylase revealed a subpopulation of dopaminergic neurons (approximately 28%) within the pars compacta which contained retrogradely transported BDNF. Experiments in which a mixture of BDNF and the retrograde tracer fluorogold were simultaneously infused for 7 days into the striatum revealed BDNF and fluorogold single-labeled neurons as well as BDNF and fluorogold dual-labeled cells within the substantia nigra, pars compacta. These observations indicate that only a subpopulation of neurons within the substantia nigra retrogradely transport BDNF following intrastriatal infusion and thus only a subpopulation of cells may be responsive to the trophic influences of BDNF. The retrograde transport of trophins, such as BDNF, represents a unique neuroanatomical tool to selectivity map the location of specific neurotrophin-responsive systems. Unraveling the trophic anatomy of BDNF will aid in understanding its role in development, degeneration, and experimental animal models of regeneration providing essential data for its use in clinical neurodegenerative disorders including Parkinson's disease.
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PMID:Intrastriatal infusions of brain-derived neurotrophic factor: retrograde transport and colocalization with dopamine containing substantia nigra neurons in rat. 752 78

The irreversible mitochondrial toxin 3-nitropropionic acid (3-NPA) is a specific inhibitor of succinate dehydrogenase. We performed stereotaxic unilateral injections of 3-NPA into the nigrostriatal dopaminergic pathway in rats in order to examine its specific effects on the dopamine system. The 3-NPA-treated rats displayed unidirectional apomorphineinduced rotations, suggesting that 3-NPA selectively damages dopaminergic neurons when injected into the nigrostriatal pathway. In situ hybridization 7 weeks postinjection indicated a decrease in tyrosine hydroxylase (TH) mRNA to 30% of the noninjected side in the substantia nigra pars compacta (P < 0.05) and decreased to 62% of the noninjected side in the ventral tegmental area (VTA) (nonsignificant) of 3-NPA-lesioned rats. The number of TH mRNA positive cells showed statistically significant decreases in substantia nigra and VTA (P < 0.001) within the lesioned side. In contrast, expression of mRNAs encoding choline acetyltransferase, p75 low-affinity NGF receptor, neurotrophin tyrosine kinase receptors Trk and TrkB, and brain-derived neurotrophic factor showed neuronal sparing in several other regions of the brain. The results suggest that the nigrostriatal dopaminergic system might be selectively vulnerable to 3-NPA and demonstrate that it is possible to employ 3-NPA in a model of partial lesion of the nigrostriatal dopaminergic system resembling early stages of Parkinson's disease.
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PMID:Specific lesions in the extrapyramidal system of the rat brain induced by 3-nitropropionic acid (3-NPA). 772 Aug 19

Amyotrophic lateral sclerosis, Parkinson's disease, and Alzheimer's disease are major human neurodegenerative disorders, the etiologies for which remain unknown. Although a unique subset of neurons is particularly affected in each of the three diseases, they have several intriguing overlapping similarities. Evidence is reviewed supporting the hypothesis that these diseases result from an inability to protect against accumulated damage by free radicals due to oxidative stress. If oxidative stress underlies or exacerbates the etiology of these diseases, then agents that effectively attenuate brain tissue lipid peroxidation or otherwise limit free radical damage may hold promise for the treatment of these neurodegenerative diseases. Although antioxidant chemical supplementation may provide effective therapy, the most effective therapy for neurodegenerative diseases may be treatment with specific neurotrophic, survival-promoting proteins. For example, brain-derived neurotrophic factor promotes survival of spinal motor neurons and mesencephalic dopaminergic neurons. One mechanism through which these proteins may exert their protection may be by stimulating endogenous defenses against oxidative stress and damage by free radicals. This hypothesis is being tested in several laboratories and provides exciting direction both for basic neurobiological research and therapeutic drug discovery.
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PMID:Oxidative stress, age-related neurodegeneration, and the potential for neurotrophic treatment. 774 72

The recent molecular cloning of BDNF and CNTF based on traditional protein purification and protein sequencing and the identification and cloning of NT-3 and NT-4 by homology cloning strategies has led to a tremendous flurry of interest in the biology of these proteins and initiation of studies to assess their potential utility in neurological disorders ranging through degenerative disease, stroke and ischemia, trauma and peripheral neuropathies. Tissue culture studies have been very useful in identifying neuronal specificities of the neurotrophins and CNTF and in combination with localization studies of these growth factors and their receptors have provided the basis for in vivo studies. Initial animal studies with BDNF indicate efficacy of BDNF in models of Alzheimer's and Parkinson's disease and small fiber sensory neuropathy. Studies with CNTF have similarly progressed from in vitro findings, especially the discovery that CNTF is a growth factor for motor neurons, to in vivo findings where CNTF has been shown to be effective in slowing symptoms of motor neuron dysfunction in three genetic models. Based on these positive animal data, CNTF is currently in clinical trials for the potential treatment of motor neuron disease or amyotrophic lateral sclerosis (ALS), also known as Lou Gehrig's disease.
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PMID:Neurotrophic growth factors and neurodegenerative diseases: therapeutic potential of the neurotrophins and ciliary neurotrophic factor. 783 3

Studies of the trophic activities of brain-derived neurotrophic factor and neurotrophin-3 indicate that both molecules support the survival of a number of different embryonic cell types in culture. We have shown that mRNAs for brain-derived neurotrophic factor and neurotrophin-3 are localized to specific ventral mesencephalic regions containing dopaminergic cell bodies, including the substantia nigra and ventral tegmental area. In the present study, in situ hybridization with 35S-labeled cRNA probes for the neurotrophin mRNAs was combined with neurotoxin lesions or with immunocytochemistry for the catecholamine-synthesizing enzyme tyrosine hydroxylase to determine whether the dopaminergic neurons, themselves, synthesize the neurotrophins in adult rat midbrain. Following unilateral destruction of the midbrain dopamine cells with 6-hydroxydopamine, a substantial, but incomplete, depletion of brain-derived neurotrophic factor and neurotrophin-3 mRNA-containing cells was observed in the ipsilateral substantia nigra pars compacta and ventral tegmental area. In other rats, combined in situ hybridization and tyrosine hydroxylase immunocytochemistry demonstrated that the vast majority of the neurotrophin mRNA-containing neurons in the substantia nigra and ventral tegmental area were tyrosine hydroxylase immunoreactive. Of the total population of tyrosine hydroxylase-positive cells, double-labeled neurons constituted 25-50% in the ventral tegmental area and 10-30% in the substantia nigra pars compacta, with the proportion being greater in medial pars compacta. In addition, tyrosine hydroxylase/neurotrophin mRNA coexistence was observed in neurons in other mesencephalic regions including the retrorubral field, interfascicular nucleus, rostral and central linear nuclei, dorsal raphe nucleus, and supramammillary region. The present results demonstrate brain-derived neurotrophic factor and neurotrophin-3 expression by adult midbrain dopamine neurons and support the suggestion that these neurotrophins influence dopamine neurons via autocrine or paracrine mechanisms. These data raise the additional possibility that inappropriate expression of the neurotrophins by dopaminergic neurons could contribute to the neuropathology of disease states such as Parkinson's disease and schizophrenia.
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PMID:Dopaminergic neurons in rat ventral midbrain express brain-derived neurotrophic factor and neurotrophin-3 mRNAs. 791 99

Linkage studies were performed in three families (A, B, and C) with autosomal dominantly inherited parkinsonism affecting multiple members in three generations. Affected individuals exhibited the cardinal signs and symptoms of Parkinson's disease, with a mean age of onset of 51, 62, and 61 years in Families A, B, and C, respectively. Parkinsonian symptoms responded to L-dopa treatment, and an [18F]6-fluoro-L-dopa positron emission tomography scan in 1 affected member of Family B showed decreased striatal uptake typical of Parkinson's disease. Ancestors of all three families were traced to a small region in northern Germany and southern Denmark, suggesting the possibility of a common mutation. Linkage studies were performed with polymorphic markers associated with the following candidate genes: the genes for glutathione peroxidase (GPX1, 3q11), tyrosine hydroxylase (TH, 11p15.5), brain-derived neurotrophic factor (BDNF, 11p14), catalase (CAT, 11p13), amyloid precursor protein (APP, 21q21), copper-zinc superoxide dismutase (SOD1, 21q21), and debrisoquin 4-hydroxylase (CYP2D6, 22q13.1). Summed lod scores for all families excluded linkage to the genes GPX1, TH, APP, SOD1, and CYP2D6, as well as to the chromosomal region containing the genes CAT and BDNF. If families were analyzed individually, exclusion was possible for two (Family A), six (Family B), and five (Family C) of the seven candidate genes. There was strong evidence against linkage for the remaining loci in all families analyzed individually, except for TH, which was uninformative in Families A and B, and CYP2D6, which gave slightly positive pairwise lod scores in Family A. Our results indicate that the candidate genes investigated are not involved in the etiology of parkinsonism in these families.
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PMID:Genetic linkage studies in autosomal dominant parkinsonism: evaluation of seven candidate genes. 791 97

The trophism of brain-derived neurotrophic factor (BDNF) for dopaminergic cells in culture has led to significant interest in the role of BDNF in the etiology and potential treatment of Parkinson disease. Previous in vivo investigation of BDNF delivery to axotomized substantia nigra dopaminergic neurons in the adult rat has shown no protective effect. In this study, we produced nigral degeneration by infusing 1-methyl-4-phenylpyridinium (MPP+), a mitochondrial complex I inhibitor and the active metabolite of 1-methyl-4-phenyl-1,2,3,6- tetrahydropyridine (MPTP), into the rat striatum. The subsequent loss of nigral neurons was presumably due to mitochondrial toxicity after MPP+ uptake and retrograde transport to the substantia nigra. We engineered immortalized rat fibroblasts to secrete human BDNF and implanted these cells near the substantia nigra 7 days before striatal MPP+ infusion. We found that BDNF-secreting fibroblasts markedly increased nigral dopaminergic neuronal survival when compared to control fibroblast implants. The observation that BDNF prevents MPTP-induced dopaminergic neuronal degeneration in the adult brain has significance for the treatment of neurodegenerative disorders, which may involve mitochondrial dysfunction, such as Parkinson disease.
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PMID:Implanted fibroblasts genetically engineered to produce brain-derived neurotrophic factor prevent 1-methyl-4-phenylpyridinium toxicity to dopaminergic neurons in the rat. 819 93


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