Improvement of intestinal toxicity of 5-fluorouracil by conagenin, a low molecular immunomodulator.

The effect of conagenin (CNG) on intestinal toxicity induction by 5-fluorouracil (5-Fu) was investigated. In mice given sublethal doses of 5-Fu (50mg/kg, i.v.) for 5 consecutive days, a decrease in body weight and diarrhea accompanied with hemorrhaging of the duodenum, atrophy of cecum and reduced small intestine length appeared. The administration of CNG in combination with 5-Fu inhibited thoe side effects induced by 5-Fu. Although all mice given 5-Fu alone were died within 13 days, 3 out of 10 mice treated with CNG survived for more than 21 days. The cytotoxicity of 5-Fu was not affected by CNG in vitro. The antitumor activity of 5-Fu was improved by CNG in increasing the number of surviving mice.