CYTOKERATIN, LECTIN, AND ACIDIC MUCIN MODULATION IN DIFFERENTIATING COLONIC EPITHELIAL-CELLS OF MICE AFTER FEEDING WESTERN-STYLE DIETS

Several studies have recently reported the development of colonic epit helial cell hyperproliferation in rodents following the ingestion of W estern-style diets. In this study, additional measurements related to differentiation and maturation of the colonic epithelial cells were ma de after feeding this type of diet. Two Western-style diets high in fa t and phosphate content and low in calcium and vitamin D were fed to C 57BL/6J mice for 12, 24, and 52 weeks. Diet A contained American Blend fat as a source of lipids, diet B contained corn oil, and control die t C was a standard AIN-76A semisynthetic diet which is lower in fat co ntent and higher in calcium and vitamin D. Colonic epithelial cells we re studied for three biomarkers: cytokeratin catalogue no. 18 (clone L E64) expression, soybean agglutinin carbohydrate lectin binding, and a cidic mucins including sialo- and sulfomucins. Feeding of diets A and B revealed that colonic epithelial cells had increased expression of c ytokeratin catalogue 18 and SBA carbohydrate lectin binding compared t o controls (P = 0.0001 for diet A versus C and diet B versus C). Signi ficant differences were found between diets B and C (P = 0.0001) and d iets A and C (P = 0.0001) in total acidic mucins and in the ratio of s ialomucin:sulfomucin (P = 0.0001), These findings demonstrate that bot h functional and structural modifications occurred in colonic epitheli al cells under these dietary conditions, and further defined this rode nt model for preclinical evaluation of nutritional and chemopreventive interventions.