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)

Most of the identified constituents of the filamentous inclusions characteristic of the neurodegenerative diseases of aging are derived from the cytoskeleton. This study was undertaken to define immunocytochemically the cytoskeletal constituents of the filamentous cytopathologic marker of idiopathic Parkinson disease, the Lewy body (LB). An array of antibodies specific to neurofilaments, tubulin, microtubule associated proteins (tau, MAP1 and MAP2) and Alzheimer neurofibrillary tangles (NFT) were used to immunostain sections containing LB. All the antibodies to tubulin, MAP1 and MAP2 and the majority of the antibodies to neurofilaments and NFT recognized LB. The two monoclonal antibodies to NFT that recognize LB also react with ubiquitin, which has been identified in NFT. The prominent NFT component, tau, is apparently not incorporated into LB. These findings suggest that the presence of tau might not be a prerequisite to the formation of abnormal filaments. Therefore, although LB contain elements of neurofilaments, microtubules and ubiquitin, as do other abnormal neuronal filaments, they are distinct in composition. These distinctive and shared features may provide useful insights regarding the mechanisms underlying the formation of filaments in LB as well as those of other neuronal inclusions.
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PMID:Lewy bodies contain epitopes both shared and distinct from Alzheimer neurofibrillary tangles. 245 16

The antigenic components of Lewy bodies in the cerebral cortex and substantia nigra in 5 cases of diffuse Lewy body disease were examined by immunocytochemistry, using antibodies to neurofilaments (in the phosphorylated or non-phosphorylated forms); to ubiquitin; to the microtubule-associated proteins MAP1, MAP2 and tau; to isolated Alzheimer paired helical filaments, and to tubulin, in the tyrosinated and non-tyrosinated forms. Immunoreactivity with antibodies to cytoskeletal components was identical to that previously described for Lewy bodies of idiopathic Parkinson disease, with the exception that the inclusions of diffuse Lewy body disease (in both cortex and substantia nigra) were stained by an antibody to tau protein. Our findings indicate that although the inclusions found in diffuse Lewy body disease share structural and epitopic features with the inclusions of idiopathic Parkinson disease, they also have distinguishing characteristics (in addition to the differing neuronal populations involved). Also, they suggest that although the inclusions in both conditions appear similar, they probably have different pathogenetic origins.
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PMID:The presence of tau distinguishes Lewy bodies of diffuse Lewy body disease from those of idiopathic Parkinson disease. 254 30

The aim of this study was to achieve a better understanding of the integration in striatal medium-sized spiny neurons (MSNs) of converging signals from glutamatergic and dopaminergic afferents. The review of the literature in the first section shows that these two types of afferents not only contact the same striatal cell type, but that individual MSNs receive both a corticostriatal and a dopaminergic terminal. The most common sites of convergence are dendritic shafts and spines of MSNs with a distance between the terminals of less than 1-2 microns. The second section focuses on synaptic transmission and second messenger activation. Glutamate, the candidate transmitter of corticostriatal terminals, via different types of glutamate receptors can evoke an increase in intracellular free calcium concentrations. The net effect of dopamine in the striatum is a stimulation of adenylate cyclase activity leading to an increase in cAMP. The subsequent sections present information on calcium- and cAMP-sensitive biochemical pathways and review the regional and subcellular distribution of the components in the striatum. The specific biochemical reaction steps were formalized as simplified equilibrium equations. Parameter values of the model were chosen from published experimental data. Major results of this analysis are: at intracellular free calcium concentrations below 1 microM the stimulation of adenylate cyclase by calcium and dopamine is at least additive in the steady state. Free calcium concentrations exceeding 1 microM inhibit adenylate cyclase, which is not overcome by dopaminergic stimulation. The kinases and phosphatases studied can be divided in those that are almost exclusively calcium-sensitive (PP2B and CaMPK), and others that are modulated by both calcium and dopamine (PKA and PP1). Maximal threonine-phosphorylation of the phosphoprotein DARPP requires optimal concentrations of calcium (about 0.3 microM) and dopamine (above 5 microM). It seems favourable if the glutamate signal precedes phasic dopamine release by approximately 100 msec. The phosphorylation of MAP2 is under essentially calcium-dependent control of at least five kinases and phosphatases, which differentially affect its heterogeneous phosphorylation sites. Therefore, MAP2 could respond specifically to the spatio-temporal characteristics of different intracellular calcium fluxes. The quantitative description of the calcium- and dopamine-dependent regulation of DARPP and MAP2 provides insights into the crosstalk between glutamatergic and dopaminergic signals in striatal MSNs. Such insights constitute an important step towards a better understanding of the links between biochemical pathways, physiological processes, and behavioural consequences connected with striatal function. The relevance to long-term potentiation, reinforcement learning, and Parkinson's disease is discussed.
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PMID:Postsynaptic integration of glutamatergic and dopaminergic signals in the striatum. 783 76

Ubiquitin-positive Lewy neurites and Lewy bodies are found in idiopathic Parkinson's disease (PD) and diffuse Lewy body disease (DLBD). We found that, in three patients with PD and one with DLBD, microtubule-associated protein 5 (MAP5) immunostaining was consistently present in both Lewy neurites and Lewy bodies throughout the brainstem and forebrain regions affected in the disease. In contrast, other cytoskeletal markers (neurofilaments and MAP2) could be demonstrated in only a small fraction of Lewy bodies and neurites. Confocal microscopy demonstrated that MAP5 immunolabeling was located around the perimeter of the ubiquitin-positive labeling which occupied the central region of the neurite and Lewy body, with some overlap between MAP5 and ubiquitin staining. In contrast, in those Lewy bodies and neurites immunopositive for phosphorylated and non-phosphorylated neurofilament proteins, the neurofilament labeling was quite peripheral to the ubiquitin staining, with little or no overlap. Our results suggest MAP5 is more closely associated with the ubiquitinated proteins of Lewy bodies and neurites than other cytoskeletal proteins.
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PMID:Microtubule-associated protein 5 is a component of Lewy bodies and Lewy neurites in the brainstem and forebrain regions affected in Parkinson's disease. 877 50

The search for specific neurotrophic factors that will eventually be used to reduce or arrest the rate of degeneration of dopaminergic neurons in Parkinson's disease is being pursued by first testing the ability of putative compounds to increase the survival of dopaminergic neurons in primary cultures of the fetal, ventral mesencephalon. This research has intensified in recent years. The experimental procedures used by different laboratories in these studies differ widely, and meaningful comparisons of the results obtained are accordingly difficult to make. Some important experimental variables include the age of the fetal tissue used; the dissection technique used to isolate the ventral mesencephalon; the percentage of dopaminergic neurons present in the culture initially; handling of the tissue during dissection; the technique used to disperse the cells; the use of serum; the technique of plating the cells; the attachment factors used; detachment and loss of cells during the staining procedure; the age of the cultures at the time of analysis; the uneven distribution of cells at the time of analysis and the use of imaging techniques in the analysis. We show that when the E14 rat embryo is used, it is possible to consistently obtain a culture with 20% of tyrosine hydroxylase-positive neurons. Neither the plating density in the range of 7.8 x 10(3) to 1.25 x 10(5) cells/cm2, nor the percentage of serum in the growth medium affected the percentage of cells that expressed TH initially, at 4 or 12 h after plating. When the cells were plated as 25 microliters droplets, called microislands (area approximately 12.5 mm2), and allowed to attach before additional growth medium was added, cell density remained uniform at the center of the microisland for the duration of the culture. Restriction of the analysis of cell survival to the center of the microisland therefore helped to decrease the variability in counting that could occur when cells are dispersed over a larger area. In contrast, in an 8-well chamber slide or 35 mm petri dish, in which the whole area is plated, cell density was consistently higher at the edge (edge effect), versus the centre, by a factor of about three. The use of microisland cultures also has the additional benefit of increasing by a factor of about five the number of individual cultures that can be set up per liter, and a proportionate reduction in the number of animals used per experiment. When the percentage of serum in the growth medium was 0% always, or 10% for the first 12 h, and 0% thereafter, or 10% always, the number of TH-pos neurons per field (using a x 20 objective, column factor 1.25; area 320 microns2) after 5 days in culture (DIV5) was < 1,3-8 and 14-22, respectively. Under the same experimental conditions, the number of neurons (MAP2-positive) per field was 5-8, 18-30 and 45-65 (N = 10 in all cases), respectively. Serum deprivation therefore has a highly deleterious effect on neuronal survival in culture. We suggest that cultures that were exposed to serum at any stage of the experiment, should not be referred to as "serum-free', since even a brief exposure to serum exerts a protective effect on neurons, and especially on dopaminergic neurons. Instead, the percentage and kind of serum used, the exact usage, and the duration of exposure of the cells to serum should be stated. Finally, it is suggested that where possible, an imaging system with manual count and journaling capabilities be used in the analysis. The methods described are illustrated by dose-response curves of the neurotrophic effects of BDNF, NGF-beta and IL-6 versus percentage survival on dopaminergic neurons, when grown in serum-free medium throughout.
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PMID:Standardized methods to bioassay neurotrophic factors for dopaminergic neurons. 884 22

In susceptible species, aluminum induces cytoskeletal changes in which neurofilaments accumulate in neuronal cell bodies and proximal axonal enlargements. To determine if microtubule-associated proteins (MAPs) are altered in this model, we examined the spinal cords of aluminum- and saline-treated control rabbits at several time points after treatment. Transient decreases in tau and MAP2 immunoreactivity in neurons in aluminum-intoxicated rabbits were demonstrated with immunocytochemistry. An antibody directed against Alzheimer's disease paired helical filaments labeled neurons in aluminum-treated rabbits but not controls. MAP5 immunoreactivity in the cell body cytoplasm was displaced by aluminum-induced tangles. The transient decreases in MAP2 and tau immunoreactivity did not reflect alterations in protein levels measured using immunoblotting. The transient antigenic changes in tau and MAP2 may reflect conformational changes in these cytoskeletal proteins. Aluminum-induced pathology provides a model for studying perturbations in MAPs and neurofilament proteins that are characteristic of many human neurodegenerative diseases such as Alzheimer's disease, diffuse Lewy body disease, Parkinson's disease, and amyotrophic lateral sclerosis.
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PMID:Aluminum-induced neuropathology: transient changes in microtubule-associated proteins. 894 45

Both deprenyl and rasagiline (R(+)-N-propargyl-1-aminoindane mesylate), at a concentration of 1-10 microM, increased survival in vitro of rat E14 mesencephalic dopaminergic neurons that had been primed with 10% serum for 12 h (p < 0.05). Rasagiline, but not deprenyl, also increased total neuronal (MAP2-positive) survival (p < 0.05) Under serum-free conditions, rasagiline, but not deprenyl, retained its neuroprotective action on dopaminergic neurones. GABAergic neurons were not affected by either deprenyl or rasagiline. Clorgyline, an MAO-A inhibitor, did not exert any of these effects. The protective action of rasagiline on dopaminergic neurons, even under stringent serum-free conditions, is striking, and warrants further investigation for a role in the treatment of Parkinson's disease.
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PMID:Increased survival of dopaminergic neurons by rasagiline, a monoamine oxidase B inhibitor. 955 42

Rat embryonic d 14 (E14) mesencephalic cells, 2.5% of which are glioblasts, were incubated in medium containing 10% of fetal bovine serum for 12 h and subsequently expanded in a serum-free medium using basic fibroblast growth factor (bFGF) as the mitogen. On a single occasion, after more than 15 d in culture, several islets of proliferating, glial-like cells were observed in one dish. The cells, when isolated and passaged, proliferated rapidly in either a serum-free or serum-containing growth medium. Subsequent immunocytochemical analysis showed that they stained positive for GFAP and vimentin, and negative for A2B5, O4, GalC, and MAP2. Serum-free conditioned medium (CM) prepared from these cells caused a fivefold increase in survival and promoted neuritic expansion of E14 mesencephalic dopaminergic neurons in culture. These actions are similar to those exerted by CM derived from primary, mesencephalic type-1 astrocytes. The pattern of expression of the region-selective genes; wnt-1, en-1, sis showed that 70% of the cells were heteroploid, and of these, 50% were tetraploid. No apparent decline in proliferative capacity has been observed after 25 passages. The properties of this cell line, named ventral mesencephalic cell line one (VMCL1), are consistent with those of an immortalized, type-1 astrocyte. The mesencephalic origin of the cell line, and the pattern and potency of the neurotrophic activity exerted by the CM, strongly suggest that the neurotrophic factor(s) identified are novel, and will likely be strong candidates with clinical utility for the treatment of Parkinson's disease.
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PMID:An immortalized, type-1 astrocyte of mesencephalic origin source of a dopaminergic neurotrophic factor. 1034 91

Cerebrolysin is a brain-derived peptide drug that increases the BBB-GLUT1 and MAP2 genes expression, thus exerting a neuroprotective effect. The present study aimed at investigating in patients with Parkinson's disease (PD) influence of Cerebrolysin infusions (intravenously, 10 ml during 10 days) combined with levodopa treatment on the electroencephalographic (EEG) indices of brain activity: P300 potential, contingent negative variation (CNV) and recovery functions of the cortical auditory evoked potentials, which reflect the postexcitatory inhibition at the paired stimulation. Nineteen PD patients, mean age 61.4 +/- 1.7 years; disease stage according to M.M. Hoehn and M.D. Yahr, 1967-2.2 +/- 0.1) and 18 age-matched healthy controls were studied. In the patients with essential differences of the EEG indices, comparing to the normal values, statistically significant changes were revealed: a decrease of P300 latency from 419.4 +/- 23.5 to 356.3 +/- 18.4 ms (8 patients, 42%); an increase of CNV duration from 423.1 +/- 93.3 to 600.6 +/- 38.5 ms; 2-fold increase of CNV mean amplitude and 3-fold increase of CNV square (8 patients, 42%) and strengthening of postexcitatory inhibition in auditory system at the paired stimulation (13 patients, 68%). In conclusion, Cerebrolysin may be recommended as an additional neuroprotective drug for brain functions improvement in the complex pathogenetic therapy of earlier PD stages.
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PMID:[Effect of cerebrolysin on the electroencephalographic indices of brain activity in Parkinson's disease]. 1534 36

Ascorbic acid (AA) has been shown to increase the yield of dopaminergic (DA) neurons derived from basic fibroblast growth factor (bFGF)-expanded mesencephalic precursors. To understand the molecular mechanisms underlying this phenomenon, we used cDNA microarray analysis to examine differential expression of neuronal genes following AA treatment. The putative precursor cells were isolated from E13 rat ventral mesencephalons and expanded in the presence of bFGF. Cells were incubated in mitogen-free media supplemented with 200 microM AA or were left untreated as a control, and total RNA was isolated at different time points (expansion stage and 1, 3, and 6 days after induction of differentiation) and subjected to cDNA microarray analysis. Differentiation was evaluated by Western blot analysis and immunocytochemistry of neuron-specific markers. AA treatment of the mesencephalic precursors increased the expression of neuronal (MAP2) and astrocytic (glial fibrillary acidic protein) markers and the percentage of tyrosine hydroxylase (TH)-positive cells. The microarray analysis revealed that 12 known genes were up-regulated and 20 known genes were down-regulated in expansion-stage AA-treated cells. Six days after the induction of differentiation, AA-treated cells showed up-regulation of 48 known genes and down-regulation of 5 known genes. Our results identified several proteins, such as transferrin, S-100, and somatostatin, as being differentially regulated in AA-treated mesencephalic precursors. This novel result may lead to a better understanding of the molecular mechanisms underlying the AA-induced differentiation of mesencephalic precursors into DA neurons and may form the basis for improved DA neuronal production for treatment of Parkinson's disease patients.
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PMID:Changes of gene expression profiles during neuronal differentiation of central nervous system precursors treated with ascorbic acid. 1537 4


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