Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UMLS:C0015672 (fatigue)
 51,768 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

We undertook a study to investigate the therapeutic potential of orally administered melatonin in patients with advanced melanoma. Forty-two patients received melatonin in doses ranging from 5 mg/m2/day to 700 mg/m2/day in four divided doses. Two were excluded from analysis. After a median follow-up of 5 weeks, six patients had partial responses, six additional patients had stable disease. Sites of response included the central nervous system, subcutaneous tissue and lung. The median response duration was 33 weeks for the partial responders. There was a suggestion of a dose-response relationship. The toxicity encountered was minimal and consisted primarily of fatigue in 17 of 40 patients. Melatonin also appeared to reduce basal levels of follicle-stimulating hormone (FSH). No significant changes were encountered in serum levels of luteinizing hormone (LH) or thyroid stimulating hormone (TSH). We conclude that further study of melatonin as a potentially useful agent in metastatic melanoma is warranted.
 ...
PMID:Melatonin therapy of advanced human malignant melanoma. 182 32

At two different times of year (spring and autumn) an oral preparation of the pineal neurohormone melatonin, or placebo, was administered to 12 healthy volunteers (10 men and two women in spring: the same group minus one man in autumn) daily at 1700 h for 1 month (spring), or 3 weeks (autumn) using a double-blind cross-over protocol. The daily dose was 2 mg melatonin in 5 ml corn-oil, and placebo consisted of the vehicle only. In spring the anterior pituitary hormones LH, PRL, GH together with T4, cortisol, testosterone and melatonin were measured at 1- to 6-h intervals for 24 h in plasma on the day following the last dose. In autumn PRL, cortisol and melatonin levels were measured on the last day of treatment. Subjective fatigue, mood and sleep records were kept throughout the studies. Melatonin increased early evening fatigue and actual sleep, but had no effect on mood: these results are reported in full elsewhere. Melatonin administration had no effect on the levels or 24-h rhythm of LH, GH, T4, testosterone or cortisol. An earlier fall in the nocturnal PRL was observed on both occasions. Overall PRL levels were higher in spring than in autumn. In five of the subjects, the secretion of endogenous melatonin was advanced by 1-3 h in the presence of exogenous melatonin. These observations suggest that the potential therapeutic use of melatonin as a hypnotic or in the treatment of jet lag is unlikely to be complicated by undesirable endocrine effects.
 ...
PMID:The effects of exogenous melatonin on endocrine function in man. 374 33

Melatonin (0.1-1.0 mg/kg) reduced isolation-induced distress vocalizations (DVs) in young domestic chickens in a dose-dependent manner. This effect was unaffected by the administration of d-amphetamine (1.0 mg/kg) suggesting that melatonin's effects were not merely due to fatigue. The melatonin reduction in DVs was not naloxone reversible, indicating an action independent of the endogenous opioid system. However, chronic pretreatment with naltrexone facilitated the melatonin effect, suggesting a complex relationship between melatonin and the endogenous opioids in regulating distress vocalizations. Chickens exhibited a marked reduction in DVs when isolation chambers were darkened, suggesting endogenous, as well as exogenous, melatonin mediation of isolation distress; however; pinealectomy only partially reversed the darkness effect. Pinealectomized animals, like control animals, exhibited a reduction in DVs following melatonin treatment; however, the melatonin effect was shorter lasting. The implications that these results may have for socialization and emotional distress are discussed.
 ...
PMID:The effects of melatonin on isolation distress in chickens. 782 45

Melatonin (10, 20, 40, or 80 mg, PO) or placebo was administered at 1145 hours on five separate occasions to 20 healthy male volunteers and the effects on serum melatonin levels, mood, performance, and oral temperature were monitored. Subjects were studied between 0930 and 1700 hours. A battery of interactive computer tasks designed to assess performance and mood was completed, oral temperature was measured, and blood samples were taken for serum melatonin radioimmunoassay. The areas under the time-melatonin concentration curve (AUC) varied significantly in proportion to the various melatonin doses. Compared with placebo treatment, all melatonin doses significantly decreased oral temperature, number of correct responses in auditory vigilance, response latency in reaction time, and self-reported vigor. Melatonin also increased self-reported fatigue, confusion, and sleepiness.
 ...
PMID:Effect of pharmacological daytime doses of melatonin on human mood and performance. 787 Oct 62

In humans, exposure to bright light at night suppresses the normal nocturnal elevation in circulating melatonin. Oral administration of pharmacological doses of melatonin during the day, when melatonin levels are normally minimal, induces fatigue. To examine the relationship between illumination, human pineal function, and behavior, we monitored the overnight serum melatonin profiles and behavioral performance of 24 healthy male subjects. On each of three separate occasions subjects participated in 13.5 h (1630-0800 h) testing sessions. Each subject was assigned to an individually illuminated workstation that was maintained throughout the night at an illumination level of approximately 300, 1500, or 3000 lux. Melatonin levels were significantly diminished by light treatment, F(2, 36) = 12.77, p < 0.001, in a dose-dependent manner. Performance on vigilance, reaction time, and other tasks deteriorated throughout the night, consistent with known circadian variations in these parameters, but independent of ambient light intensity and circulating melatonin levels.
 ...
PMID:Effects of illumination on human nocturnal serum melatonin levels and performance. 843 55

Exposure to a 50/60-Hz electromagnetic field can decrease the nocturnal production of melatonin in rodents. Melatonin is considered to be a marker of circadian rhythms, and abnormalities in its secretion are associated with clinical disorders, including fatigue, sleep disruption, mood swings, impaired performance, and depression, which are consequences of desynchronisation. Interestingly, some epidemiological studies have been reported finding most of these clinical disorders in individuals living or working in an environment exposed to electromagnetic fields. This experiment was designed to look for the possible effects of acute exposure (9 hours) to 50-Hz linearly polarized magnetic fields (10 mu T) on the pineal function. Thirty-two young men (20-30 years old) were divided into two groups (control group, i.e., sham-exposed: 16 subjects; exposed group: 16 subjects). All subjects participated in two 24-hour experiments to evaluate the effects of both continuous and intermittent exposure to linearly polarized magnetic fields. They were synchronized with a diurnal activity from 08:00 to 23:00 and nocturnal rest. The experiment lasted two months (mid-February to mid-April). The subjects were exposed to the magnetic fields (generated by three Helmholtz coils per bed) from 23:00 to 08:00, while lying down. Blood samples were collected during each session at 3-hour intervals from 11:00 to 20:00 and hourly from 22:00 to 08:00. Total urine was collected every 3 hours from 08:00 to 23:00 and once during the night, from 23:00 to 08:00. The levels of serum melatonin and its metabolite in urine (6-sulfatoxymelatonin) in exposed men did not differ significantly from those in control (sham-exposed) subjects. This study shows that nocturnal acute exposure to either continuous or intermittent 50-Hz linearly polarized magnetic fields of 10 mu T does not affect melatonin secretion in humans.
 ...
PMID:Magnetic fields and pineal function in humans: evaluation of nocturnal acute exposure to extremely low frequency magnetic fields on serum melatonin and urinary 6-sulfatoxymelatonin circadian rhythms. 864 83

It is still controversial whether the pineal hormone melatonin can be characterized as a hypnotic. We therefore measured subjective sleepiness and waking EEG power density in the range of 0.25-20 Hz after a single dose of melatonin (5 mg). During an 8 h mini-constant routine protocol, melatonin administered in a double blind cross-over design to healthy young men at 1300 h or 1800 h increased subjective sleepiness, as rated half-hourly on three different scales (Visual Analogue Scale, Akerstedt Sleepiness Symptoms Check List, Akerstedt Sleepiness Scale) and objective fatigue as evidenced by augmented waking EEG power density in the theta/alpha range (5.25-9 Hz). The increase in subjective sleepiness reached significance 40 min and 90 min after melatonin administration (at 1300 h and 1800 h, respectively) and lasted for 3 h (at 1300 h) and 5 h (at 1800 h). The increase in the theta/alpha frequencies of the waking EEG occurred immediately after melatonin ingestion and stayed significantly higher parallel to the higher sleepiness ratings. However, the EEG changes appeared before the subjective symptoms of sleepiness became manifest. There was a significant correlation between salivary melatonin levels and the timing of increased subjective sleepiness. Melatonin had no effects on mood.
 ...
PMID:Daytime melatonin administration enhances sleepiness and theta/alpha activity in the waking EEG. 872 87

Currently available as a dietary supplement, the pineal hormone melatonin is portrayed by the media as a formidable weapon against disease and aging. Accordingly, primary health care providers should be cognizant of which of its proposed uses are supported by biomedical research and which are, as yet, unproven. Melatonin entrains circadian rhythms and, thus, can treat jet lag, delayed sleep phase syndrome, and sleep disorders in the blind and in some neurologically impaired children. By virtue of its hypnotic effect, melatonin can mitigate insomnia in the elderly. Reductions in melatonin secretion have been associated with many disorders, including cardiovascular disease, Alzheimer's, diabetes, SIDS, and aging; however, melatonin's role in their etiology and/or pathophysiology is unproven. Preliminary studies suggest a possible adjuvant therapeutic role for melatonin in cancer therapy. Melatonin secretion is reduced by alcohol, caffeine, and some commonly prescribed drugs. Since tolerance, fatigue, and other side effects have been reported, melatonin use on consecutive nights should be avoided and only the lowest effective hypnotic dose should be taken.
 ...
PMID:Melatonin: media hype or therapeutic breakthrough? 905 17

Jet lag is a travel-induced circadian rhythm disorders. Symptoms of jet lag include difficulty sleeping at the new sleep time, daytime sleepiness and fatigue, and impaired performance. Treatment of jet lag includes both behavioral and pharmacological component. A short-half-life benzodiazepine hypnotic for several nights at the new sleep time have been recommended to decrease jet lag symptoms. Melatonin also can alleviate jet lag and bright light exposure is a useful countermeasure for jet lag.
 ...
PMID:[Jet lag syndrome]. 950 41

Adults have an intrinsic body clock which regulates a complex series of rhythms including sleep and wakefulness, fatigue and cognitive ability. This endogenous clock naturally runs more slowly than the solar day and is entrained to a 24-h rhythm primarily by the alternation of light and darkness. Jet lag, shift-work sleep disorder, and some of the chronic insomnias are caused by a temporal discrepancy of the body clock relative to the surrounding environment and social network. The underlying mechanisms and general management are described. Both bright light and melatonin therapy have potential in the management of these disorders. Traditionally, bright light therapy has been used to alleviate the depression associated with seasonal affective disorder. Melatonin has received much ill-formed publicity, it being claimed that it is a panacea and an 'antiageing' treatment. Both of these treatment approaches are reviewed.
 ...
PMID:Disorders of the sleep-wake cycle in adults. 964 Apr 37


1 2 3 4 Next >>