Inactivation of neutrophil-derived hypochlorous acid by nimesulide: a potential mechanism for the tissue protection during inflammation.

The anti-inflammatory drug nimesulide was found to effectively reduce the availability of hypochlorous acid, the most potent chlorinated oxidant generated by the myeloperoxidase system of activated neutrophils. Such an effect was observed at concentrations achievable in vivo after the oral administration of the drug. Higher concentrations of nimesulide were also found to limit both the oxygen consumption and the superoxide anion/hydrogen peroxide production by neutrophils. Taken together, the results suggest that nimesulide is endowed with a high potential to efficiently control the harmful effects of oxidants produced by neutrophils at inflammatory tissue sites.