Melatonin as an antioxidant: under promises but over delivers

  title={Melatonin as an antioxidant: under promises but over delivers},
  author={Russel Joseph Reiter and Juan Carlos Mayo and Dun-Xian Tan and Rosa Mar{\'i}a Sainz and Mois{\'e}s Alejandro Alatorre-Jim{\'e}nez and Lilan Qin},
  journal={Journal of Pineal Research},
Melatonin is uncommonly effective in reducing oxidative stress under a remarkably large number of circumstances. It achieves this action via a variety of means: direct detoxification of reactive oxygen and reactive nitrogen species and indirectly by stimulating antioxidant enzymes while suppressing the activity of pro‐oxidant enzymes. In addition to these well‐described actions, melatonin also reportedly chelates transition metals, which are involved in the Fenton/Haber–Weiss reactions; in… 
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Although the vast majority of studies proved the antioxidant capacity of melatonin and its derivatives, a few studies using cultured cells found that melatonin promoted the generation of ROS at pharmacological concentrations in several tumor and nontumor cells; thus, melatonin functioned as a conditional pro‐oxidant.
Protective Effects of Melatonin and Mitochondria-targeted Antioxidants Against Oxidative Stress: A Review.
Melatonin seems to be a mitochondria-targeted antioxidant and has similar protective actions as the synthetic antioxidants, which may make it a potent protector against a variety of free radical-related diseases.
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Melatonin, an ubiquitous and pleiotropic molecule, exerts efficient protection against oxidative stress and ameliorates oxidative/nitrosative damage by a variety of mechanisms, which may contribute in reducing metal‐induced toxicity as postulate here.
Melatonin in plants.
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Protective effects of melatonin in reducing oxidative stress and in preserving the fluidity of biological membranes: a review
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Quinone reductase 2 as a promising target of melatonin therapeutic actions
  • J. Boutin
  • Biology, Chemistry
    Expert opinion on therapeutic targets
  • 2016
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