Sulfated polysaccharides, but not cellulose, increase colonic mucus in rats with loperamide-induced constipation

Colonic mucus is decreased in a rat model of spastic constipation, and some types of water-insoluble dietary fiber increase colonic mucus when consumed by rats for several weeks. However, little is known about the effect of water-soluble dietary fiber on the colonic mucus. The aim of the present study was to investigate the effect of various types of water-soluble dietary fiber on colonic mucus in a rat model of spastic constipation. Oral administration of 1.5 mg/day of carrageenan and chondroitin sulfate increased the fecal excretion, epithelial mucin production, thickness of the mucous layer, and amount of luminal mucus in loperamide-administered rats. Sodium alginate, 5 mg/day, thickened the mucus layer at the fecal surface. Cellulose, 5 mg/day, increased the fecal excretion but not the colonic mucus. Carrageenan, chondroitin sulfate, and sodium alginate, but not cellulose, increased colonic mucus in the rat model of spastic constipation.