Long-Term Effects of Capsaicin on Intestinal Thiamine Absorption in Mice

Abstract

Long-term effects of capsaicin, a pungent principle of capsicum fruits, on intestinal thiamine absorption were examined in mice. Inhibition of thiamine absorption was noted after oral administration of capsaicin (1mg/kg body weight/day) for 1, 2, 4, or 8 weeks. When given for 12 weeks at a dose of 2mg/kg body weight/day, the principle was also inhibitory; however, the inhibition of thiamine absorption was not observed if the dose level was 1mg/kg body weight/day. Reductions in the activity of intestinal Na⁺, K⁺-ATPase and intestinal mucosal ATP content were responsible for the inhibition of thiamine absorption by capsaicin. The decrease in the intestinal mucosal ATP content was accompanied by a decrease in the activities of mitochondrial NADH cytochrome c reductase and cytochrome oxidase. These results suggest that inhibition of intestinal thiamine absorption by capsaicin in mice is due to the inhibition of intestinal mucosal Na⁺, K⁺-ATPase and the reduction in mucosal ATP content.