Exercise-Induced Oxidative Stress Reduced with Melatonin

A recent study indicates that melatonin modulates oxidative stress and inflammation produced during exercise. Strenuous exercise promotes the release of inflammatory mediators, produces free radicals, and may result in damage to muscle tissue. Melatonin is a hormone secreted from the pineal gland with significant antioxidant activity.

The subjects in this study consisted of men supplemented with melatonin and individuals receiving a placebo. The subjects completed a physical test consisting of a constant run and including several degrees of high-effort. The test run was 50 km with nearly 2800 meters of ramp in permanent climbing and changeable climatic conditions. The subjects were evaluated for inflammatory mediators using blood and urine tests, measuring the pro-inflammatory cytokines tumor necrosis factor (TNF)-alpha, interleukin (IL)-6, and IL-1ra, as well as 8-hydroxy-2’-deoxyguanosine, a marker of oxidative stress, and isoprostane, a marker of lipid peroxidation.

The study results indicated that melatonin supplementation during high-intensity exercise significantly mitigated the increase in lipid peroxidation seen with intense exercise and enhanced antioxidant enzyme activities. Furthermore, melatonin supplementation reduced the over-expression of pro-inflammatory mediators and modulated the effects of the pro-inflammatory cytokines.

The study authors stated, “In summary, melatonin supplementation before strenuous exercise reduced muscle damage through modulation of oxidative stress and inflammation signaling associated with this physical challenge.”

Reference:

Ochoa JJ, Díaz-Castro J, Kajarabille N, García C, Guisado IM, De Teresa C, Guisado R. Melatonin supplementation ameliorates oxidative stress and inflammatory signaling induced by strenuous exercise in adult human males. J Pineal Res. 2011 Apr 21. Published Online Ahead of Print.