Protective effect of polysaccharides from Angelica sinensis on ulcerative colitis in rats.

Ulcerative colitis (UC) involves the dysregulation of intestinal mucosal immunity and imbalance between the reactive oxygen species (ROS) and the endogenous anti-oxidants. While the protective effects of Angelica sinensis (AS) polysaccharides on neutrophil-dependent gastric mucosal damage have been reported, similar protective effects on UC are still uncertain. Hence our study aimed to investigate the effects of AS polysaccharides on rats with acute UC induced by 2,4-dinitrobenzene sulphonic acid (DNBS) evaluated after 24 h. Intrarectal injection of DNBS significantly reduced the glutathione (GSH) content, increased malondialdehyde concentration and raised the amount of apoptotic cells in colon tissues, which were related to oxidative stress and attenuated by AS polysaccharides pretreatment (5 mg/ml and 10 mg/ml). These findings suggest that oxidative stress and GSH depletion are highly associated with the pathological mechanism of UC, and the protective effects of AS polysaccharides are closely related to the prevention of oxidative stress, which may occur during neutrophil infiltration in the pathological process of UC.