Regulation of antioxidant enzymes: a significant role for melatonin

Abstract

: 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, regulating the expression of several genes. Melatonin also influences both antioxidant enzyme activity and cellular mRNA levels for these enzymes. In the present report, we review the studies which document the influence of melatonin on the activity and expression of the antioxidative enzymes glutathione peroxidase, superoxide dismutases and catalase both under physiological and under conditions of elevated oxidative stress. We also analyze the possible mechanisms by which melatonin regulates these enzymes.

Does Melatonin Ameliorate Neurological Changes Associated With Alzheimer’s Disease in Ovariectomized Rat Model?

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Melatonin: A pleiotropic molecule regulating inflammation

“…Even though the mechanisms through which melatonin stimulates these signal transduction pathways have been extensively studied [12][13][14][15][16][17][18][19][20][21], little is known about the resulting cellular effects: MT1/MT2 receptors have been shown to mediate melatonin-dependent decrease of tumor cell proliferation [22] and anti-apoptotic effects [23][24][25]; MT1 seems to be responsible for the general response to photoperiodic signals [26].…”

Melatonin as potential candidate to prevent the toxicity induced by chemical warfare agents

“…In an interesting review article, Korkmaz et al (2008) proposed that the mechanism of delayed sulfur mustard toxicity may be due to epigenetic disruption that occurs in cells in which the genome has genetic and/or epigenetic mutations. As a multifunctional indole, melatonin could counteract delayed sulfur mustard toxicity, modulating the expression of mRNA levels for antioxidant enzymes under physiological conditions and during increased oxidative stress (Rodriguez et al 2004).…”