Melatonin antioxidant mechanisms

Keywords Indole Melatonin Antioxidant activity Oxidative stress Mechanism... 

Discussion on Possible Antioxidant Mechanisms of Melatonin and Related Indole Derivatives... 

The mechanism of melatonin s interaction with reactive species probably involves donation of an electron to form the melatoninyl cation radical or through a radical addition at the site C3. Other possibilities include hydrogen donation from the nitrogen atom or substitution at position C2, C4, and C7 and nitrosation [169]. The mechanisms by which melatonin protects against LP most likely involve direct or indirect antioxidant and free-radical scavenging activities of this indoleamine [169,171]. 2-Phenyl indole derivatives have redox properties because of the presence of an electron-rich aromatic ring system that allows the indoleamine to easily function as an electron donor. For these derivatives, the possible antioxidant mechanism might be most probably toward carbon-centered radicals described by Antosiewicz et al. [172]. 

Tan, D. X., Reiter, R. J., Manchester, L. C. et al. (2002). Chemical and physical properties and potential mechanisms melatonin as a broad spectrum antioxidant and free radical scavenger. Curr. Top. Med. Chem. 2, 181-97. 

Hardeland R (2005) Antioxidative protection by melatonin multiplicity of mechanisms from radical detoxification to radical avoidance. Endocrine 27 119-130... 

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