Melatonin’s Antioxidant Properties: Molecular Mechanisms

  • Rüdiger HardelandEmail author


Melatonin acts as an antioxidant in various ways. Direct scavenging of free radicals requires elevated concentrations, which are present in some high-melatonin organisms and in melatonin-synthesizing organs and used in experimental systems designed for antagonizing oxidotoxicity. Upregulation of antioxidant enzymes occurs at physiological concentrations but is tissue and species specific. Moreover, melatonin prevents excessive radical generation by antiexcitatory and anti-inflammatory actions; by supporting mitochondrial electron flux, thereby reducing electron leakage; and, presumably, by optimizing phase relationships within the circadian multioscillator system.


Antioxidant Circadian Excitotoxicity Free radicals Inflammation Melatonin Mitochondria 


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© Springer India 2014

Authors and Affiliations

  1. 1.Johann Friedrich Blumenbach Institute of Zoology and AnthropologyGöttingenGermany

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