Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0085632 (apathy)
 4,089 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Depressive mood is frequently associated with Parkinson's syndrome, but it may also occur as a precursor of this disease. As regards the subtypes of Parkinson's disease, the frequency of depressive states is significantly higher in the type dominated by akinesia and rigidity than in the type dominated by tremor. On the basis of biochemical changes, certain aspects of the depression can be successfully treated by substitution therapy: L-dopa medication may increase the reduced dopamine values in the striatum, thereby improving drive. Substitution with L-tryptophan raises the lowered serotonin values in the reticular formation, which may influence sleep disturbances. The changes of basic mood, however, which are characteristic of depression, such as cheerlessness and apathy, are the dopamine of antidepressive medication; only these drugs can re-establish the biochemical balance to a large extent.
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PMID:[Depression and Parkinson syndrome]. 287 39

The serotonin hypothesis postulates a decreased function of this neurotransmitter in the central nervous system of depressed patients. L-tryptophan and--more specific--5-hydroxytryptophan are natural precursors of this biogenic amine. Results of numerous therapeutic trials with L-tryptophan are not convincing of this compound's antidepressant efficacy in marked to severe endogenous depressions. On the other hand, it cannot be excluded that it is effective in moderate dysphoric states with apathy and sleep disturbances. However, possible toxic effects of high and long term use render its clinical use doubtful. The antidepressant efficacy of 5-hydroxytryptophan has not been proven. However, the possibility exists that a serotonin deficient subgroup of depressed patients responds to this substance and further, that it has depression prophylactic properties. As both tryptophan and 5-hydroxytryptophan are less effective than tricyclic antidepressants and not without side effects they do not appear to be useful antidepressants.
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PMID:[Serotonin precursors as antidepressive agents: a review]. 660 3

A recent major theory was that a meal high in carbohydrate increased the rate that tryptophan enters the brain, leading to an increase in the level of the neurotransmitter serotonin that modulates mood. Although such a mechanism may be important under laboratory conditions it is unlikely to be of significance following the eating of any typical meal. As little as 2-4% of the calories of a meal as protein will prevent an increased availability of tryptophan. Arguably the food with the greatest impact on mood is chocolate. Those who crave chocolate tend to do so when they feel emotionally low. There have been a series of suggestions that chocolate's mood elevating properties reflect 'drug-like' constituents including anandamines, caffeine, phenylethylamine and magnesium. However, the levels of these substances are so low as to preclude such influences. As all palatable foods stimulate endorphin release in the brain this is the most likely mechanism to account for the elevation of mood. A deficiency of many vitamins is associated with psychological symptoms. In some elderly patients folate deficiency is associated with depression. In four double-blind studies an improvement in thiamine status was associated with improved mood. Iron deficiency anaemia is common, particularly in women, and is associated with apathy, depression and rapid fatigue when exercising.
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PMID:The effects of nutrients on mood. 1061 80

Choice behaviour can be viewed as a response to reinforcement determined by an interaction between the quantities, delays and probabilities of two outcomes. The variation in the perceived value of a reinforcer with alteration of these factors (discounting) can be modelled mathematically by hyperbolic discounting functions. Making risky choices is a feature of impulsivity and has been associated with reduced serotonin (5-hydroxytryptamine, 5-HT) function. In this study, we investigated the possible role of 5-HT in modulating probability discounting using the technique of acute tryptophan (TRP) depletion in subjects undertaking an imaginary gambling task. The gambling task consisted of choosing between two 'roulette-like' dials: 'A' which provided a smaller but nearly certain 'win' and 'B' which gave a 'win' 2.5 times the amount with a probability that was systematically varied. A series of reward sizes on dial 'A' was presented ranging from 10 pence to 10,000 pounds. The probability of winning on dial 'B' at which the subjects valued the two dials equally (indifference point) was determined as a measure of willingness to take a risk. Subjects were more likely to take a risk for smaller rewards but the indifference points in the 15 subjects who received TRP depletion did not differ from 13 who had the control drink. On a surprise retesting 1 week later there was a trend (p < 0.07) for subjects to be more willing to take risks the second time, particularly in the case of small rewards. This study does not support a role for 5-HT in modulating probabilistic choice in agreement with recent evidence from experiments with animals; however, the imaginal nature of the task and modest numbers may have influenced the result.
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PMID:The effect of acute tryptophan depletion on probabilistic choice. 1268 Jul 34

Pellagra is associated with low levels of vitamin B3 (niacin) and/or tryptophan and often involves other other B vitamins. Since the time Gasper Casal first described the disease in 1972, it was observed that the patients with pellagra were all poor, subsisted mainly on maize, and rarely ate fresh meat. Subsequent occurrences have been in the form of epidemic outbreaks, consequent to either introduction to maize as a major food or increased consumption of other niacin-deficient diets like Jowar (Sorgum vulgare). The virtual disappearance of pellagra as an endemic health problem in recent years can be attributed to a rise in the standard of living of farmers and diversification of the diet globally. The clinical picture is a combination of multisystem alterations typically involving gastrointestinal, skin and central nervous system abnormalities. The cardinal manifestations have been popularly known as the three D's, which are dementia, dermatitis and diarrhea. Psychiatric manifestations are fairly common but are easily overlooked due to their non specific nature. These are commonly seen as irritability, poor concentration, anxiety, fatigue, restlessness, apathy and depression. The occurence of psychosis in pellagra is an uncommon finding, which is usually seen in advanced stages of pellagroid encephalopathy, commonly found in chronic alcoholics. Delusional parasitosis has been also reported in this condition, although the association is still controversial. We report a case of pellagra manifesting with delusional parasitosis in a man whose delusion resolved rapidly after he started niacin-augmentation therapy. This case may provide clues to the biological underpinnings of delusional parasitosis as well as niacin treatment as treatment option in similar cases.
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PMID:Rapid resolution of delusional parasitosis in pellagra with niacin augmentation therapy. 1906 87