Effect of dietary pectin level on intestinal alkaline phosphatase activity in colon of rats fed high-fat diet

Abstract

We found that dietary 4 % glucomannan or inulin, both soluble dietary fibers, increased colon alkaline phosphatase (AP) activity and the expression of intestinal-type AP (IAP), which controls anti-inflammatory processes, in rats. Pectin, a fermentable soluble dietary fiber, differs from other fermentable fibers in its effects on colonic fermentation and the microbial composition. To clarify the effects of the dietary level of pectin on colonic IAP and tissue-nonspecific AP (TNAP), which is known to increase during colonic inflammation, male Sprague-Dawley rats were fed a 20 % fat diet with or without 1 %, 2 % or 4 % pectin, or 4 % non-fermentable soluble fiber carboxymethylcellulose (CMC), for 14 days. Dietary pectin increased colonic and fecal IAP activity as well as colonic IAP gene expression in a dose-dependent manner. Conversely, dietary 4 % CMC tended to increase colonic AP activity, which was attributable to an increase in TNAP gene expression.