Fw: [VitaminK] Abstract: Peta/ Actions of melatonin in acute and chronic inflammation.

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Peta, here's another one.

Curr Top Med Chem. 2002 Feb;2(2):153-65. Pharmacological actions of melatonin in acute and chronic inflammation.Cuzzocrea S,Reiter RJ.Institute of Pharmacology, School of Medicine, University of Messina, Gazzi,Italy.A vast number of experimental and clinical studies implicates oxygen-derivedfree radicals (especially, superoxide and the hydroxyl radical) and highenergy oxidants (such as peroxynitrite) as mediators of acute and chronicinflammation. The purpose of this review is to summarize the pharmacologicalactions of melatonin in acute and chronic inflammation. Reactive oxygenspecies can modulate a wide range of toxic oxidative reactions. Theseinclude initiation of lipid peroxidation, direct inhibition of mitochondrialrespiratory chain enzymes, inactivation of glyceraldehyde-3-phosphatedehydrogenase, inhibition of membrane sodium/potassium ATPase activity,inactivation of membrane sodium channels, and other oxidative modificationsof proteins. Reactive oxygen species (e.g., superoxide, peroxynitrite,hydrogen peroxide and hydroxyl radical) are all potential reactants capableof initiating DNA single strand breakage, with subsequent activation of thenuclear enzyme poly (ADP ribose) synthetase (PARS), leading to eventualsevere energy depletion of the cells, and necrotic-type cell death. Thesetoxic reactions are likely to play a role in the pathophysiology ofinflammation. Melatonin has been shown to possess both in vitro and in vivoimportant antioxidant activities as well as to inhibit the activation ofpoly (ADP ribose) synthetase. A large number of experimental studies havedocumented that melatonin exerts important anti-inflammatory actions.PMID: 11899098 [PubMed - indexed for MEDLINE]