Source and level of protein fed to mice may affect their intestinal mucin production

Abstract

Mucins are large heavily glycosylated proteins which form the major component of mucus that protects epithelial surfaces of ducts in the body. The effect of the source and level of dietary protein on mucin production and intestinal mucosal morphology was investigated in mice. Thirty two male weanling ICR Swiss mice were randomized into 4 groups of 8 mice each. The four groups of mice were randomly assigned to four diets whose sources of protein were either from plant or animal origin and the level of each protein source was either 10% or 20% crude protein. Mice were provided the respective diets for 14 days and euthanized on the fifteenth day. Jejunal sections of their intestines were removed, fixed in methacarn, embedded in paraffin, sectioned and stained with alcian blue‐periodic acid Schiff (AB‐PAS) stain to visualize mucins and quantify the goblet cells. AB‐PAS stained jejunal sections showed an increase in mucus in mice fed diets containing proteins of animal origin. The number of goblet cells was higher in diets containing protein of animal origin (p<0.05). The increase in goblet cell number was greater for the higher protein level. The length of the villi did not seem to vary among the four different diets. It is concluded that the source and level of protein fed to mice may be influencing their intestinal mucin production.Research was supported by East Tennessee State University.