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 mammalian cells, mitochondria provide energy from aerobic metabolism. They play an important regulatory role in apoptosis, produce and detoxify free radicals, and serve as a cellular calcium buffer. Neurodegenerative disorders involving mitochondria can be divided into those caused by oxidative phosphorylation (OXPHOS) abnormalities either due to mitochondrial DNA (mtDNA) abnormalities, e.g., chronic external ophthalmoplegia, or due to nuclear mutations of OXPHOS proteins, e.g., complex I and II associated with Leigh syndrome. There are diseases caused by nuclear genes encoding non-OXPHOS mitochondrial proteins, such as frataxin in Friedreich ataxia (which is likely to play an important role in mitochondrial-cytosolic iron cycling), paraplegin (possibly a mitochondrial ATP-dependent zinc metalloprotease of the AAA-ATPases in hereditary spastic paraparesis), and possibly Wilson disease protein (an abnormal copper transporting ATP-dependent P-type ATPase associated with Wilson disease). Huntingon disease is an example of diseases with OXPHOS defects associated with mutations of nuclear genes encoding non-mitochondrial proteins such as huntingtin. There are also disorders with evidence of mitochondrial involvement that cannot as yet be assigned. These include Parkinson disease (where a complex I defect is described and free radicals are generated from dopamine metabolism), amyotrophic lateral sclerosis, and Alzheimer disease, where there is evidence to suggest mitochondrial involvement perhaps secondary to other abnormalities.
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PMID:Mitochondria and degenerative disorders. 1157 22

Alteration in the isoprenoid metabolites--digoxin, ubiquinone, and dolichol--have been reported in neuronal degeneration (Parkinson's disease), oncogenesis (central nervous system glioma), functional neuropsychiatric disorders (schizophrenia and epilepsy), and immune-mediated disorders (multiple sclerosis). The coexistence of these disorders has been documented in literature and a central dysfunction related to digoxin and the isoprenoid pathway may underlie all these disorders. A family with a high prevalence of Parkinson's disease, schizophrenia, neoplasms, syndrome X, rheumatoid arthritis, and epilepsy has been described. The psychological behavioral patterns of the family were: creativity and high IQ, hypersexual behavior, reduced appetite and eating behavior, insomnia and reduced sleep patterns, increased tendency for spirituality, increased tendency for addiction, less bonding and affectionate behavior, and left handedness/right hemispheric dominance. Digoxin, an endogenous Na(+)-K+ ATPase inhibitor secreted by the hypothalamus, was found to be elevated and red blood cell (RBC) membrane Na(+)-K+ ATPase activity was found to be reduced in all the disorders and in the indexed family studied. Hypothalamic digoxin can modulate conscious perception and its dysfunction may lead to schizophrenia. Digoxin can also preferentially upregulate tryptophan transport over tyrosine, resulting in increased levels of depolarizng tryptophan catabolites, serotonin, quinolinic acid, strychnine, and nicotine, and decreased levels of hyperpolarizing tyrosine catabolites, dopamine, noradrenaline, and morphine, contributing to membrane Na(+)-K+ ATPase inhibition in all the above disorders and the indexed family. Digoxin-induced membrane Na(+)-K+ ATPase inhibition can result in increased intracellular Ca2+ and reduced Mg2+ levels, leading on to glutamate excitotoxicity, oncogene activation, and immune activation. Digoxin-induced altered Ca2+/Mg2+ ratios, reduced ubiquinone, and increased dolichol can affect glycoconjugate metabolism, membrane formation and structure, and mitochondrial function, leading to the diverse disorders described above, including those in the indexed family. The isoprenoid pathway and neurotransmitter patterns were compared in right-handed/LH dominant and left-handed/RH dominant individuals. The left-handed/RH dominant individuals compared to right-handed/LH dominant individuals had elevated hydroxymethylglutarylcoenzyme A reductase activity, with increased serum digoxin and dolichol levels. The serum ubiquinone, serum Mg2+ and RBC Na(+)-K+ ATPase activity were reduced in left-handed/RH dominant individuals. The left-handed/RH dominant individuals compared to right-handed/LH dominant individuals had elevated levels of serum tryptophan, quinolinic acid, serotonin, nicotine, and strychnine. The levels of tyrosine, dopamine, noradrenaline, and morphine were low in left-handed/RH dominant compared to right-handed/LH dominant individuals. The hyperdigoxinemic state indicates right hemispheric dominance. Hypothalamic digoxin can thus function as the master conductor of the neuroimmunoendocrine orchestra and coordinate the functions of various cellular organelles.
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PMID:Central role of hypothalamic digoxin in conscious perception, neuroimmunoendocrine integration, and coordination of cellular function: relation to hemispheric dominance. 1232 12

Oxidative stress plays an important role in many neurodegenerative conditions including Alzheimer's disease and Parkinson's disease. 4-Hydroxynonenal (HNE), a lipid-soluble aldehydic product of membrane peroxidation, has been known to decrease neuronal survival by impairing Na+, K+, and -ATPase activity. HNE also increases neuronal vulnerability to excitotoxic injury and disrupts homeostasis by activating proteases which mediate the destruction of cellular protein and structure. The present study demonstrated that the hydrophobic HIV protease inhibitor, ritonavir inhibited HNE-mediated apoptosis in hippocampal primary neurons. In neurons exposed to oxidative stress induced by HNE (1 microM), ritonavir at 100 pM increased cell survival and completely abolished the apoptotic effects of HNE (P < 0.01). Ritonavir and its analogues might have useful cytoprotective effects for use in limiting the natural course of tissue injury after conditions where oxidative stress plays a role.
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PMID:Ritonavir protects hippocampal neurons against oxidative stress-induced apoptosis. 1238 58

Glial cell line-derived neurotrophic factor (GDNF) was reported to be effective for treating subjects with neurodegenerative diseases such as Parkinson's disease. In search of finding a compound which promotes GDNF secretion, we found that concanamycin A (ConA), a vacuolar ATPase (V-type ATPase) inhibitor purified from Streptomyces diastatochromogens, enhanced GDNF secretion from glioma cells. The rat glioma cell line, C6, and the human glioma cell lines, U87MG and T98G, abundantly expressed GDNF mRNA, and secreted GDNF into culture media, and this event was potently enhanced by a Ca(2+) ionophore and by phorbol ester, as noted in other cells. ConA concentration dependently and potently increased GDNF release from C6, U87MG and T98G cells into culture media. In addition, ConA enhanced GDNF secretion from astrocyte primary cultures prepared from the human fetus with the same potency seen in glioma cell lines. Likewise, another V-type ATPase inhibitor, bafilomycinA1 facilitated GDNF release from C6, U87MG and T98G glioma cells, in a concentration-dependent manner. The potencies of these V-type ATPase inhibitors in enhancing GDNF secretion were consistent with those which inhibited V-type ATPase activity. These results suggest that blockade of V-type ATPase potently stimulates the secretion of GDNF from glial cells. The V-type ATPase inhibitors may be beneficial to use for the treatment of diseases in which increase in GDNF could be effective.
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PMID:Increase in secretion of glial cell line-derived neurotrophic factor from glial cell lines by inhibitors of vacuolar ATPase. 1254 48

Previous work from our laboratory has demonstrated the presence of endogenous strychnine in the mammalian brain and human serum samples. The present study examines the role of strychnine in neuropsychiatric disorders. Strychnine is synthesized from tryptophan. The blood levels of tyrosine, tryptophan, and strychnine were studied as also RBC membrane Na(+)-K+ ATPase activity. It was found that serum tyrosine levels were reduced and that tryptophan levels were elevated in all neuropsychiatric disorders studied with a reduction in RBC Na(+)-K+ ATPase activity. Strychnine was present in significant amounts in the serum of patients with epilepsy, Parkinson's disease, and manic depressive psychosis. The presence of strychnine in significant amounts could be related to elevated tryptophan levels, suggesting the synthesis of these alkaloids from tryptophan. Na(+)-K+ ATPase inhibition present in most of the disorders could be related to increased depolarizing strychninergic transmission. The role of strychnine in the pathogenesis of these disorders, in the setting of membrane Na(+)-K+ ATPase inhibition, is discussed.
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PMID:Endogenous strychnine: description of hypo- and hyperstrychninergic state in relation to neuropsychiatric diseases. 1258 24

A family with a high prevalence of Parkinson's disease, schizophrenia, neoplasms, syndrome-X, rheumatoid arthritis and epilepsy has been described. The psychological behavioural patterns of the family were as follows--creativity and high IQ, hypersexual behaviour, reduced appetite and eating behaviour, insomnia and reduced sleep patterns, increased tendency for spirituality, increased tendency for addiction, less of bonding and affectionate behaviour and left handedness. Digoxin, an endogenous Na(+)-K(+) ATPase inhibitor secreted by the hypothalamus, was found to be elevated and RBC membrane Na(+)-K(+) ATPase activity was found to be reduced in all the disorders and in the indexed family studied. Hypothalamic digoxin can modulate conscious perception and its dysfunction may lead to schizophrenia. Digoxin can also preferentially upregulate tryptophan transport over tyrosine resulting in increased levels of depolarising tryptophan catabolites - serotonin, quinolinic acid, strychnine and nicotine and decreased levels of hyperpolarising tyrosine catabolites dopamine, noradrenaline and morphine contributing to membrane Na(+)-K(+) ATPase inhibition in all the above disorders and the indexed family. Digoxin induced membrane Na(+)-K(+) ATPase inhibition can result in increased intracellular Ca(2+) and reduced Mg(++) levels leading to glutamate excitotoxicity, oncogene activation and immune activation. Digoxin induced altered Ca(++)/Mg(++) ratios, reduced ubiquinone and increased dolichol can affect glycoconjugate metabolism, membrane formation and structure and mitochondrial function leading to the diverse disorders described above including those in the indexed family. The isoprenoid pathway and neurotransmitter patterns were compared in right-handed/left hemispheric dominant and left-handed/right hemispheric dominant individuals. The biochemical patterns in the indexed family and the diverse disorders studied correlated with those obtained in right hemispheric dominance. The hyperdigoxinemic state indicates right hemispheric dominance. Hypothalamic digoxin can thus function as the master conductor of the neuroimmunoendocrine orchestra and co-ordinate the functions of various cellular organelles.
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PMID:Hypothalamic digoxin--central role in conscious perception, neuroimmunoendocrine integration and coordination of cellular function--relation to hemispheric dominance. 1260 43

The isoprenoid pathway produces four key metabolites important in cellular function--digoxin (endogenous membrane Na(+)-K+ ATPase inhibitor), dolichol (important in N-glycosylation of proteins), ubiquinone (free-radical scavenger), and cholesterol (component of cellular membranes). This study assessed the changes in the isoprenoid pathway and the consequences of its dysfunction in Parkinson's disease (PD). There was an elevation in plasma HMG CoA reductase activity, serum digoxin and dolichol levels, and a reduction in serum magnesium, RBC membrane Na(+)-K+ ATPase activity, and serum ubiquinone levels. Serum tryptophan, serotonin, strychnine, nicotine, and quinolinic acid were elevated, while tyrosine, morphine, dopamine, and noradrenaline were decreased. The total serum glycosaminoglycans (GAG) and glycosaminoglycan fractions (except chondroitin sulphates and hyaluronic acid), the activity of GAG degrading enzymes, carbohydrate residues of serum glycoproteins, the activity of glycohydrolase-beta galactosidase, and serum glycolipids were elevated. HDL cholesterol was reduced and free fatty acids increased. The RBC membrane glycosaminoglycans, hexose and fucose residues of glycoproteins and cholesterol were reduced, while phospholipid was increased. The activity of all serum free-radical scavenging enzymes, concentration of glutathione, alpha tocopherol, iron binding capacity, and ceruloplasmin decreased significantly in PD, while the concentration of serum lipid peroxidation products and nitric oxide increased. A dysfunctional isoprenoid pathway and related cascade are important in the pathogenesis of Parkinson's disease. A hypothalamic digoxin mediated model for Parkinson's disease is also postulated.
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PMID:Hypothalamic digoxin-mediated model for Parkinson's disease. 1285 80

The diverse damaging effects of dopamine (DA) oxidation products on brain subcellular components including mitochondrial electron transport chain have been implicated in dopaminergic neuronal death in Parkinson's disease. It has been shown in this study that DA (50-200 microM) causes dose-dependent inhibition of Na+, K+-ATPase activity of rat brain crude synaptosomal-mitochondrial fraction during in vitro incubation up to 2 h. The enzyme inactivation is prevented by catalase and the metal-chelator (diethylenetriamine penta-acetic acid) but not by superoxide dismutase or hydroxyl-radical scavengers like mannitol and dimethylsulphoxide (DMSO). Further, reduced glutathione and cysteine, markedly prevent DA-mediated inactivation of Na+, K+-ATPase. Under similar conditions of incubation, DA (200 microM) leads to the formation of quinoprotein adducts (protein-cysteinyl catechol) with synaptosomal-mitochondrial proteins and the phenomenon is also prevented by glutathione (5 mM) or cysteine (5 mM). The available data imply that the inactivation of Na+, K+-ATPase in this system involves both H2O2 and metal ions. The reactive quinones by forming adducts with protein thiols also probably contribute to the process, since reduced glutathione and cysteine which scavenge quinones from the system protect Na+, K+-ATPase from DA-mediated damage. The inactivation of neuronal Na+, K+-ATPase by DA may give rise to various toxic sequelae with potential implications for dopaminergic cell death in Parkinson's disease.
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PMID:Dopamine oxidation products inhibit Na+, K+-ATPase activity in crude synaptosomal-mitochondrial fraction from rat brain. 1286 86

The membrane composition and the isoprenoid pathway metabolites important in maintaining cell membrane integrity was studied in neurological and psychiatric disorders. The results indicate alteration in cholesterol:phospholipid ratio of the RBC membrane which is increased in glioma, schizophrenia, and bipolar mood disorder (MDP); decreased in multiple sclerosis and Parkinson's disease; and not significantly altered in epilepsy. The concentration of total glycosaminoglycans (GAG), hexose, and fucose decreased in the RBC membrane and increased in the serum. The RBC membrane Na+-K+ ATPase activity was reduced and serum HMG CoA reductase activity was increased. There were increased serum levels of digoxin, cholesterol, and dolichol and decreased levels of ubiquinone. The serum magnesium and tyrosine levels were reduced and tryptophan increased. The results indicate a defect in membrane formation and a decreased membrane Na+-K+ ATPase activity in all the disorders studied. The results are discussed, and a hypothesis regarding the relationship between these disorders and defective membrane architecture and membrane Na+-K+ ATPase inhibition is presented.
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PMID:Isoprenoid pathway-related membrane dysfunction in neuropsychiatric disorders. 1458 55

Psychiatric abnormalities have been described in primary neurological disorders like multiple sclerosis, primary generalized epilepsy, Parkinson's disease, subacute sclerosing panencephalitis (SSPE), central nervous system glioma, and syndrome X with vascular dementia. It was therefore considered pertinent to compare monoamine neurotransmitter pattern in schizophrenia with those in the disorders described above. The end result of neurotransmission is changes in membrane Na(+)-K+ ATPase activity. Membrane Na(+)-K+ ATPase inhibition can lead to magnesium depletion, which can lead to an upregulated isoprenoid pathway. The isoprenoid pathway produces three important metabolites--digoxin, an endogenous membrane Na(+) -K+ ATPase inhibitor; ubiquinone, a membrane antioxidant and component of mitochondrial electron transport chain; and dolichol, important in N-glycosylation of protein. The serum/plasma levels of digoxin, dolichol, ubiquinone, magnesium, HMG CoA reductase activity, and RBC Na(+)-K+ ATPase activity were estimated in all these disorders. The result showed that the concentration of serum tryptophan and serotonin was high and serum tyrosine, dopamine, adrenaline, and noradrenaline low in all the disorders studied. The plasma HMG CoA reductase activity, serum digoxin, and serum dolichol levels were high and serum ubiquinone levels, serum magnesium, and RBC Na(+)-K+ ATPase activity were low in all the disorders studied. The significance of these changes in the pathogenesis of syndrome X, multiple sclerosis, primary generalized epilepsy, schizophrenia, SSPE, and Parkinson's disease is discussed in the setting of the interrelationship between these disorders documented in literature.
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PMID:Schizoid neurochemical pathology-induced membrane Na(+)-K+ ATPase inhibition in relation to neurological disorders. 1460 43


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