MPO and colitis: Liu et al. (2009) investigated the anti-colitis effect of 4-methoxy-5-hydroxycanthin-6-one on DSS-induced colitis in experiments with rats and found that 4-methoxy-5-hydroxycanthin-6-one (20 and 40 mg/kg of body weight in rats, p.o.)could significantly mitigate the severity of colitis by preventing colon length shortening and reducing colonic MPO activity and serum TNF-α levels.