Effect of n-butyric acid on epithelial cell proliferation of pig colonic mucosa in short-term culture.

Short-chain fatty acids (SCFA) such as acetic, propionic and n-butyric acids produced by hindgut bacteria stimulate gut epithelial cell proliferation through afferent neural and efferent non-neural systemic transmissions beside a probable local mechanism. In the present study, we developed an experimental system using pig hindgut mucosa in short term culture to clarify the mechanism of the local trophic effect of SCFA. Pig mucosal tissue pieces of the distal colon were cultured in RPMI 1640 medium containing glutamine, 20% (v/v) newborn calf serum and n-butyric acid (0, 0.5, 1.0 or 5.0 mmol/L). Crypt cell production rate from 0.5 to 3.5 and from 21 to 24 hours of culture was measured. Butyric acid increased crypt cell production rate of pit distal colon only at 5 mmol/L. The effect of butyric acid did not differ between samples of different length of n-butyric acid exposure. The effect of n-butyric acid in this study resembled to that found in human biopsied specimens of the colon. The present results also indicated that epithelial cells of pig colonic mucosa in short-term culture presented here retained the proliferative activity and the responsiveness to n-butyric acid.