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

Despite a realisation that antioxidants will not delay ageing in healthy older people, there is increasing scientific interest in the role of free radical oxidants in a number of diseases associated with older age. For most of these diseases there is suggestive theoretical and laboratory evidence but not confirmatory clinical evidence. Free radical damage seems likely to be significant in the pathophysiology of atherosclerosis, ischaemia-reperfusion injury, Parkinson's disease, cataract, some cancers and rheumatoid arthritis. Evidence to suggest a protective effect from antioxidant vitamins exists for ischaemic heart disease, cataract and some cancers. Attempts to influence the outcome of other diseases such as ischaemia-reperfusion injury, Parkinson's disease and rheumatoid arthritis have so far failed to achieve positive results. Research interest in the field is increasing although hampered by methodological difficulties and the limited financial return for drug companies. In the meantime there seems no reason to discourage older people who wish to ingest extra vitamin E and vitamin C. A diet with adequate vegetables and fruits should provide sufficient beta carotene.
 ...
PMID:Free radicals, antioxidants and preventive geriatrics. 806 Feb 75

Four patients with vitamin E deficiency and sensory ataxia were studied using [18F]dopa positron emission tomography. The 2 most disabled patients, who had severe and prolonged vitamin E deficiency due to abetalipoproteinemia, showed reduced [18F]dopa uptake in both putamen and caudate. Putaminal uptake was in a similar range to that seen in Parkinson's disease. Studies of [3H]mazindol binding in the striatum of vitamin E--deficient rats indicated a reduced number of dopamine terminals, which was most severe in ventrolateral striatum. These observations suggest that severe and prolonged vitamin E deficiency results in loss of nigrostriatal nerve terminals, and support the hypothesis that oxidative stress may contribute to the etiology of Parkinson's disease.
 ...
PMID:Nigrostriatal function in vitamin E deficiency: clinical, experimental, and positron emission tomographic studies. 812 82

Parkinson's disease responds rather dramatically to levodopa therapy during the first several years of treatment. With advancing disease, however, symptom control becomes more erratic, and some symptoms may become refractory to treatment. The use of selegiline hydrochloride (Eldepryl) has been proposed to slow the progression of Parkinson's disease; however, current evidence suggests that it is only partially effective at best, and there is no definite proof of a neuroprotective effect. Nonetheless, it is a reasonable treatment choice. Carbidopa-levodopa (Sinemet) remains the foundation of symptomatic treatment of Parkinson's disease. Clinical fluctuations occurring with advancing disease may be at least partially controlled by appropriate adjustments in dosage. A direct-acting dopamine agonist, bromocriptine mesylate (Parlodel) or pergolide mesylate (Permax), can be very helpful as adjunctive therapy to smooth these clinical fluctuations. Excessive intracellular oxidative stress has been proposed as a cause of Parkinson's disease; however, a recent multicenter trial investigating the use of high doses of the antioxidant vitamin E showed it to be ineffective. Whether other forms of nonspecific antioxidant therapy will prove beneficial is open to speculation.
 ...
PMID:Treatment of Parkinson's disease. From theory to practice. 815 48

In this article the effect of vitamin E on two extrapyramidal disorders, tardive dyskinesia and Parkinson's disease, is reviewed. After a brief description of the symptoms, the current hypotheses for the pathogenesis of these diseases are described. A summary of the clinical research that has been done to establish the effectiveness of vitamin E is given. In tardive dyskinesia four clinical trials (double-blind, placebo-controlled) showed improvement in the symptoms with vitamin E in doses of up to 1,600 IU/day. Preliminary studies concerning Parkinson's disease suggested that vitamin E (2,000 IU/day) probably cannot prevent the development of the disease. It was suggested that vitamin E is able to slow the progression of the illness. The results from a large double-blind, placebo-controlled clinical trial, however, did not show any beneficial effect of vitamin E in Parkinson's disease.
 ...
PMID:Vitamin E in extrapyramidal disorders. 822 Feb 97

Levodopa, at concentrations of 0.25 x 10(-4) M or larger, is toxic for the human neuroblastoma cell NB69. Toxicity is associated with high levels of quinones, increased activity of complex II-III, and lack of changes of complex I of the mitochondrial respiratory chain. Deprenyl, which does not alter the production of quinones, has a partial protective effect. Tocopherol, 23 or 115 x 10(-6) M, lacks significant preventive effect on levodopa toxicity, but ascorbic acid, 10(-3) M, prevents levodopa toxicity and quinone formation. Deprenyl, 10(-4) M, provides additional protection in cultures treated with levodopa and ascorbic acid. Our results indicate that ascorbic acid and deprenyl prevent levodopa neurotoxicity by unrelated mechanisms. Both compounds should be considered as complementary drugs to test for slowing the progression of Parkinson's disease.
 ...
PMID:Ascorbic acid protects against levodopa-induced neurotoxicity on a catecholamine-rich human neuroblastoma cell line. 834 Dec 91

The advance of Parkinson's disease has been suspected to be an outcome of oxidative stresses related to the metabolism of dopamine. Several recent studies have tested whether deprenyl (selegiline) or alpha-tocopherol (vitamin E) might attenuate the progression of Parkinson's disease. Although preliminary results of an 800-patient controlled clinical trial (DATATOP) suggested in 1989 that neuroprotection might be achieved with deprenyl, more recent analysis has questioned this conclusion. The apparent protective effect of deprenyl is lost after 1 year of treatment, and the drug's symptomatic antiparkinsonian effects confound an understanding of actions on the underlying disease. In the DATATOP trial, no neuroprotection was achieved with alpha-tocopherol. Methods developed in the deprenyl trials and newly discovered CSF markers of Parkinson's disease may be useful tools for future investigations of neuroprotective strategies against Parkinson's disease.
 ...
PMID:Neuroprotection by anti-oxidant strategies in Parkinson's disease. 837 28

In the pathogenesis of Parkinson's disease and senile dementia of the Alzheimer type, free radicals might play a role. Fat-soluble vitamins are a kind of anti-oxidative substance. Therefore, fat-soluble vitamins, such as vitamin E, may be useful in treatment of Parkinson's disease and senile dementia of the Alzheimer type. However, it is still unclear whether the concentration of vitamin E in the blood or in the brain tissue, in patients with Parkinson's disease or with of the senile dementia Alzheimer type, is higher than or the same as that in normal subjects. Furthermore, although the effectiveness of vitamin E in the treatment of Parkinson's disease has been reported, the usefulness of vitamin E is still obscure. Further study will be necessary, in order to clarify the role of fat-soluble vitamins in the treatment of Parkinson's disease and senile dementia of the Alzheimer type.
 ...
PMID:[Fat-soluble vitamin therapy in senile dementia and Parkinson's disease]. 848 57

The Deprenyl and Tocopherol Antioxidant Therapy of Parkinsonism (DATATOP) trial was designed to test outcomes from treatment with 10 mg of deprenyl and/or 2,000 mg of tocopherol/day in 800 untreated patients with Parkinson's disease. The need of subjects for symptomatic treatment with levodopa and the conversion of all subjects to open-label deprenyl made it possible to study the long-term effect of early deprenyl and tocopherol treatment on the later development of levodopa-associated side effects. The rate of developing these side effects did not differ among the original treatment groups (early versus late deprenyl and tocopherol versus nontocopherol). About 50% of subjects developed "wearing off," 30% dyskinesias, and 25% "freezing" in each group. At the end of the study, the groups were similarly disabled on the Hoehn-Yahr, Schwab-England, and Unified Parkinson's Disease Rating scales and took similar amounts of levodopa. Young subjects were more likely to develop wearing off, women to develop dyskinesias, and older subjects with rapidly progressive disease to develop freezing. We conclude that prior treatment with deprenyl or tocopherol did not reduce the occurrence of subsequent levodopa-associated adverse effects in this population.
 ...
PMID:Impact of deprenyl and tocopherol treatment on Parkinson's disease in DATATOP patients requiring levodopa. Parkinson Study Group. 900 6

A nested case-control study of 84 incident cases of patients with idiopathic Parkinson's disease (PD) detected by June 30, 1994 and 336 age-matched control subjects, compared previously-documented intake of total dietary vitamin E and of selected vitamin E-containing foods. All study subjects had been followed for 27 to 30 years after diet recording in the 8,006-man Honolulu Heart Study cohort. We determined PD outcomes by periodic cohort re-examination and neurologic testing, private physician reports, examination of O'ahu neurologists' office records, and continual death certificate and hospital discharge diagnosis surveillance. Data on vitamin E intake, obtained from three dietary data sets at the time of cohort enrollment (1965 to 1968), included a food-frequency questionnaire and a 24-hour photograph-assisted dietary recall administered by trained dietitians. Although absence of PD was significantly associated with prior consumption of legumes (adjusted OR = 0.27, 95% CI 0.09 to 0.78), a dietary variable preselected for high vitamin E content, neither food categories nor quartiles nor continuous variables of vitamin E consumption were significantly associated with PD occurrence. Though consistent with prior reports of PD protection afforded by legumes, and with speculation on the possible benefits of dietary or supplemental vitamin E in preventing PD, these preliminary data do not conclusively document a beneficial effect of dietary vitamin E on PD occurrence.
 ...
PMID:Case-control study of idiopathic Parkinson's disease and dietary vitamin E intake. 862 65

We report the analysis of plasma levels of vitamin E that has been found normal in 20 italian patients with Parkinson's disease (PD) confirming the previously reported results from other groups. We discuss the literature data about the possible protective effect of antioxidant agents in the PD and generally in the aging processes.
 ...
PMID:Plasma levels of vitamin E in Parkinson's disease. 874 34


<< Previous 1 2 3 4 5 6 7 8 9 10 Next >>