Effect of quercitrin on the early stages of hapten induced colonic inflammation in the rat

Quercitrin is a flavonoid with antiinflammatory activity in experimental colitis, associated with an antioxidative action and amelioration of water absorption in vivo. However, its mechanism of action is unclear. This study focuses on the effect of quercitrin (1 and 5 mg/kg) in the early stages (24 h) of trinitrobenzene sulfonic acid colitis. Treatment with the flavonoid prevented the increase in colonic malondialdehyde and inhibited nitric oxide synthase and alkaline phosphatase activity but had no significant effects on observable damage. No effect on neutrophil infiltration (myeloperoxidase) was observed. On the other hand, quercitrin exerted complex effects on colonic hydroelectrolytic transport, showing a slight potentiation of water absorption in vivo (5 mg/kg) as well as a normalization of carbachol stimulated electrogenic ionic transport in the proximal colon in vitro (5 mg/kg). It is concluded that the beneficial effects of quercitrin on trinitrobenzene sulfonic acid chronic colitis arise from an early downregulation of the inflammatory cascade that is associated with amelioration of the disturbances in hydroelectrolytic transport. (C) 2002 Elsevier Science Inc. All rights reserved.