Send to

Choose Destination
J Pineal Res. 2005 Sep;39(2):99-104.

A proposed mechanism to explain the stimulatory effect of melatonin on antioxidative enzymes.

Author information

Departamento de Morfología y Biología Celular, Facultad de Medicina, Universidad de Oviedo, Oviedo, Spain.


Melatonin, the main secretory product of the pineal gland, is known to collaborate against oxidative stress within cells, but its mechanism of action in terms of stimulating antioxidant enzymes remains unclear. Herein, we propose that melatonin modulates antioxidant enzyme activities via its interaction with calmodulin, which in turn inhibits downstream processes that lead to the inactivation of nuclear RORalpha melatonin receptor. Eventually, this nuclear transcription factor downregulates NF-kappaB-induced antioxidant enzyme expression. Therefore, the increment in antioxidant enzyme activities induced by melatonin involves the inhibition of the RORalpha pathway. Thus, in addition to its direct free radical scavenging activities, melatonin has important actions in oxidative defense by stimulating enzymes which metabolize free radicals and radical products to innocuous metabolites.

[Indexed for MEDLINE]

Supplemental Content

Full text links

Icon for Wiley
Loading ...
Support Center