A traditional Japanese medicine mitigates TNBS-induced colitis in rats.

OBJECTIVE

Differences in dietary habits may be one of the reasons that the incidence of inflammatory bowel disease has remained lower in Japan than in Western countries. We investigated whether a traditional Japanese medicine (Strong Wakamto), based on Aspergillus oryzae koji, would exert any effect on experimental colitis in rats.

MATERIAL AND

METHODS

Colitis was induced using an enema of trinitrobenzene sulfonic acid (TNBS) and ethanol. Strong Wakamto was administered for 28 days before induction of colitis and for 7 days thereafter, and the effect of this medicine was evaluated.

RESULTS

Treatment with 5% Strong Wakamto improved loss of body-weight, increased colon weight and significantly decreased the histological damage score for colon mucosa. Decreases in faecal Lactobacillus sp., superoxide dismutase activity and zinc concentrations, and the increased IL-1beta expression in colonic tissue after TNBS enema were improved when Strong Wakamto was given. The present in vitro studies indicate that administration of Strong Wakamto prevents lipopolysaccharide-induced TNF-alpha production in human macrophages.

CONCLUSIONS

Oral administration of Strong Wakamto mitigates experimental inflammatory bowel disease induced by TNBS enema in rats. The beneficial effects seem attributable to a combination of balancing microflora, immunomodulatory effects on gut macrophages, and enhancement of anti-superoxide activity in colonic tissues.