EFFECT OF DIETARY OLIGOFRUCTOSE AND INULIN ON COLONIC PRENEOPLASTIC ABERRANT CRYPT FOCI INHIBITION

Oligofructose and inulin, naturally-occurring fermentable chicory fruc tans, have been shown to stimulate the growth of bifidobacteria which are regarded as beneficial strains in the colon and inhibit colon carc inogenesis in the laboratory animal models, The present study was desi gned to determine the effect of oligofructose and inulin on the azoxym ethane (AOM)-induced preneoplastic lesions such as aberrant crypt foci (ACF) formation in the colon of male F344 rats. At 5 weeks of age, gr oups of animals were fed the AIN-76A (control) and the experimental di ets containing 10% oligofructose or inulin, At 7 weeks of age, all ani mals received s.c. injection of AOM dissolved in normal saline at a do se rate of 15 mg/kg body wt, once weekly for 2 weeks, The animals were necropsied 7 weeks after the last AOM injection, and the ACF were vis ualized under light microscopy in the formalin-fixed, unsectioned meth ylene blue-stained colons, They were distinguished by their increased size, more prominent epithelial cells and pericryptal space. The feedi ng of oligofructose or inulin significantly inhibited the ACF formatio n and the crypt multiplicity in the colon, The degree of ACF inhibitio n was more pronounced in animals fed inulin than in those fed oligofru ctose. The findings suggest that chicory fructan supplements inhibit A CF formation, an early preneoplastic marker of malignant potential in the process of colon carcinogenesis.