Induction of epithelial hypoplasia in rat cecal and distal colonic mucosa by grape antioxidant dietary fiber

Grape antioxidant dietary fiber (GADF) is a source of dietary fiber obtained from grape seeds from wine production with antioxidant capacity. The effects of GADF on cecal and distal colonic mucosal growth and the architecture of male Wistar rats were studied. Tissue DNA, RNA, and protein concentrations as well as mucosal thickness, crypt depth, and crypt density were assessed. Two groups of 10 animals were fed diet containing fiber either from cellulose or from GADF for 4 weeks. Feeding rats with GADF diet decreased mucosal DNA and protein concentrations in cecum (39%) and DNA concentration in colon (29%) compared with control (P < .0001). These changes paralleled a structural decline in mucosal thickness, crypt depth, and crypt density, but the loss was greater in cecal than distal mucosa, although the cause of this difference is unclear. Thus, the GADF diet appears to induce a loss of epithelial cellularity with shorter crypts and a decrease in the total number of crypts per millimeter, indicating that the GADF diet modifies crypt population and develops epithelial hypoplasia. Thus, this antiproliferative capacity of the GADF diet could exert a protective effect upon the large intestinal mucosa.