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)

1. Benserazide and carbidopa, decarboxylase inhibitors used in the treatment of Parkinson's disease, have been shown to inhibit the enzyme kynurenine hydrolase in rat and mouse liver. This results in reduced synthesis of nicotinamide coenzymes from tryptophan, and hence an increased reliance on dietary niacin. 2. Pellagra might be expected as a result of this inhibition of endogenous synthesis of nicotinamide nucleotides, but has not been reported in patients treated with either drug. 3. The urinary excretion of N1-methyl-nicotinamide, a product of nicotinamide nucleotide metabolism, is considerably reduced in patients treated with dopa alone or in combination with an inhibitor of peripheral dopa decarboxylase, to as low as 40% of the control value. This means that many of these patients could be classified as 'at risk' of niacin deficiency, even if not frankly deficient. 4. Patients treated with dopa plus a decarboxylase inhibitor, but not those treated with dopa alone, also show a reduced excretion of xanthurenic acid, and an increased excretion of kynurenine, as would be expected after inhibition of the kynurenine pathway, and possibly indicative of marginal vitamin B6 deficiency.
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PMID:Niacin depletion in Parkinsonian patients treated with L-dopa, benserazide and carbidopa. 47 87

The findings of a negative association between past maize (Zea mays) production and current Parkinson's disease mortality by each prefecture in Japan tends to support the hypothesis that the nutritional condition that causes niacin deficiency might protect people from Parkinson's disease. Specifically, the negative association between both the area planted for dried corn in 1960, 1970 or 1977 and the area planted for sweet corn in 1960 and age-adjusted death rates for Parkinson's disease is ecological evidence supporting the hypothesis. Extending the analysis to other cultivated crops, even stronger negative associations of age-adjusted death rates for Parkinson's disease and cultivation of rice and soybeans were found, but associations were not significant for a large variety of vegetables. The findings for soybean and rice are attributed to the correspondence (co-linearity) of cultivation of these other two seed-crops with maize. Hence, further testing of the theory of niacin deprivation and prevention of Parkinson's disease finds some circumstantial support in the cultivation patterns of a grain of poor niacin and tryptophan availability.
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PMID:Retrospective study of preventive effect of maize on mortality from Parkinson's disease in Japan. 1467 69

Enrichment of diet with Nicotinamide in the West was introduced in the 1940s to prevent the dietary deficiency disorder Pellagra. Pellagra was caused by a particular form of poor vegetarian diet leading to Nicotinamide and Tryptophan deficiency. Arguably Pellagra would have disappeared if dietary measures suggested at the time had been implemented before Nicotinamide was even discovered. Diets may sometimes now be too high in selected pyridines and inadvertently we have exchanged one neurodegenerative disease for another. Parkinson's disease triggered in contrast to Pellagra by a particular form of rich omnivorous diet. Moderation of Nicotinamide intake would be easy to begin with compared with other dietary manipulations as there is no behavior change necessary for individuals. A substantial amount of Nicotinamide can be removed when and where there is too much that has been introduced artificially and inserted where there is too little because meat is unaffordable.
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PMID:Nicotinamide: a double edged sword. 1618 23

The effects of three hydrazine derivatives on the enzymes of the tryptophan oxidative pathway and of nicotinamide nucleotide synthesis have been studied using preparations from rat liver. The compounds used were Benserazide and Carbidopa, two inhibitors of aromatic amino acid decarboxylase used together with dopa in the treatment of Parkinson's disease, and the anti-tubercular agent isoniazid. All three drugs inhibited tryptophan oxygenase and kynureninase, at concentrations that are likely to be encountered in vivo following administration to patients or experimental animals. Isoniazid, but not Benserazide or Carbidopa, also inhibited 3-hydroxy-anthranilate oxidase and nicotinamide phosphoribosyltransferase. However, these two enzymes were of the drug far in excess of those likely to be encountered in vivo. On the basis of the in vitro enzyme inhibition studies, it is not possible to explain why patients treated with isoniazid (without supplementary vitamin B(6)) develop clinical pellagra, while those treated with Benserazide or Carbidopa do not, despite biochemical evidence of niacin deficiency. It is suggested that this difference may be due either to differences in the intake of dietary niacin in these two groups of patients, or more probably to differences in the metabolism of the drugs and in their interactions with enzymes in vivo that are not apparent in vitro.
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PMID:Inhibition in vitro of the enzymes of the oxidative pathway of tryptophan metabolism and of nicotinamide nucleotide synthesis by benserazide, carbidopa and isoniazid. 2022 44

Epidemiological surveys suggest an important role for niacin in the causes of Parkinson's disease, in that niacin deficiency, the nutritional condition that causes pellagra, appears to protect against Parkinson's disease. Absorbed niacin is used in the synthesis of nicotinamide adenine dinucleotide (NAD) in the body, and in the metabolic process NAD releases nicotinamide by poly(ADP-ribosyl)ation, the activation of which has been reported to mediate 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine-induced Parkinson's disease. Recently nicotinamide N-methyltransferase (EC2.1.1.1) activity has been discovered in the human brain, and the released nicotinamide may be methylated to 1-methylnicotinamide (MNA), via this enzyme, in the brain. A deficiency in mitochondrial NADH: ubiquinone oxidoreductase (complex 1) activity is believed to be a critical factor in the development of Parkinson's disease. MNA has been found to destroy several subunits of cerebral complex 1, leading to the suggestion that MNA is concerned in the pathogenesis of Parkinson's disease. Based on these findings, it is hypothesized that niacin is a causal substance in the development of Parkinson's disease through the following processes: NAD produced from niacin releases nicotinamide via poly(ADP-ribosyl)ation, activated by the hydroxyl radical. Released excess nicotinamide is methylated to MNA in the cytoplasm, and superoxides formed by MNA via complex I destroy complex 1 subunits directly, or indirectly via mitochondrial DNA damage. Hereditary or environmental factors may cause acceleration of this cycle, resulting in neuronal death.
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PMID:Niacin metabolism and Parkinson's disease. 2143 57

Pellagra is a complex systemic disease resulting from inadequate dietary intake of coenzyme precursors nicotinamide and tryptophan. Improved nutritional habits in most developed economies have led to a decrease in clinicians' and researchers' attention to this condition and its pathophysiological bases, although new cases of pellagra have recently been identified in association with alcohol abuse and HIV infection in Western countries. Pellagra is characterized by a complex clinical picture, which can include neuropsychiatric symptoms and Parkinsonian features. Interestingly, pellagra and Parkinson's disease could share some basic pathophysiological mechanisms at the level of nicotinamide metabolism, resulting in mitochondrial dysfunction and alterations in dopaminergic pathways. Both neuropsychiatric and motor symptoms were mentioned in historical reports of pellagra cohorts. Here we present the English translation of the first detailed description of an original case of pellagra with Parkinsonian features, documented in a clinical note by Dr Giuseppe Paravicini one century ago.
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PMID:Parkinsonian features in a case of pellagra: a historical report. 2402 27

Good health and rapid progress depend on an optimal dose of nicotinamide. Too little meat triggers the neurodegenerative condition pellagra and tolerance of symbionts such as tuberculosis (TB), risking dysbioses and impaired resistance to acute infections. Nicotinamide deficiency is an overlooked diagnosis in poor cereal-dependant economies masquerading as 'environmental enteropathy' or physical and cognitive stunting. Too much meat (and supplements) may precipitate immune intolerance and autoimmune and allergic disease, with relative infertility and longevity, via the tryptophan-nicotinamide pathway. This switch favours a dearth of regulatory T (Treg) and an excess of T helper cells. High nicotinamide intake is implicated in cancer and Parkinson's disease. Pro-fertility genes, evolved to counteract high-nicotinamide-induced infertility, may now be risk factors for degenerative disease. Moderation of the dose of nicotinamide could prevent some common diseases and personalised doses at times of stress or, depending on genetic background or age, may treat some other conditions.
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PMID:Nicotinamide and Demographic and Disease transitions: Moderation is Best. 3132 Aug 5