Objective: Given that circadian rhythm disruption is associated with impairments in cognitive performance similar to those found in age-related cognitive decline, the authors investigated whether exogenous melatonin administration would improve cognitive functioning in healthy elderly subjects.
Methods: This double-blind, placebo-controlled pilot study assigned 26 healthy elderly subjects to receive either melatonin 1 mg or placebo nightly for 4 weeks.
Melatonin, the chief secretory product of the pineal gland, was recently found to be a free radical scavenger and antioxidant. This review briefly summarizes the published reports supporting this conclusion. Melatonin is believed to work via electron donation to directly detoxify free radicals such as the highly toxic hydroxyl radical.
Additionally, in both in vitro and in vivo experiments,
Antioxidant enzymes form the first line of defense against free radicals in organisms. Their regulation depends mainly on the oxidant status of the cell, given that oxidants are their principal modulators. However, other factors have been reported to increase antioxidant enzyme activity and/or gene expression.
During the last decade, the antioxidant melatonin has been shown to possess genomic actions,
Mercury, cadmium, and other heavy metals have a high affinity for sulfhydryl (-SH) groups, inactivating numerous enzymatic reactions, amino acids, and sulfur-containing antioxidants (NAC, ALA, GSH), with subsequent decreased oxidant defense and increased oxidative stress. Both bind to metallothionein and substitute for zinc, copper, and other trace metals reducing the effectiveness of metalloenzymes. Mercury induces mitochondrial dysfunction with reduction in ATP,
Mitochondrial defects have been linked to such devastating neurodegenerative diseases as Parkinson's, Huntington's, amyotrophic lateral sclerosis (ALS), multiple sclerosis (MS) and Alzheimer's as well as senile dementia's. Mitochondrial metabolic defects could affect the electron transport, the tricarboxylic acid cycle (TCA), and substrate transport. However, it is the escape of oxygen free radicals (superoxide formation) as a result of a disturbed electron transfer within the respiratory chain that is thought to underlie many of the deleterious effects of mitochondrial dysfunction.
Chronic sarcoidosis (CS) is often unresponsive to usual resultss. Melatonin, an immunoregulatory drug, was employed in CS patients in whom usual resultss were ineffective or induced severe side effects. Melatonin was given for 2 yr (20 mg/day in the first year, 10 mg/day in the second year) to 18 CS patients.
Pulmonary function tests, chest X rays,
Objective: To review the data that support the clinical use of melatonin in the results of burn patients, with special emphasis on the stimulation of the oxidative defense system, the immune system, circadian rhythm of sleep/wakefulness, and the reduction in the toxicity of therapeutic agents used in the results of burn victims.
Data Source: A MEDLINE/PubMed search from 1975 to July 2006 was conducted.