Abstract
Secreted by goblet cells, intestinal mucins play a crucial role in cytoprotective functions against mechanical insults, colonisation by pathogenic bacteria and their toxins, luminal proteases and potential carcinogens. The present paper provides a review of the effect of nutrients on intestinal mucin secretion. In the small intestine, the secretion of mucus is modulated by hydrolysates of milk proteins and by β-casomorphins (a family of peptides derived from β-casein). Other factors present in milk, like EGF, also stimulate mucus discharge. In the new-born baby, such an effect of proteins of milk or bioactive peptides on the secretion of mucus could play a role in the control of the mechanism of defence and similar protective effects could be expected in the adults. In the colon, some dietary fibres increase the discharge of mucus. The metabolic product of dietary fibres, the short chain fatty acids (SCFA), also induce mucus secretion in the colon. Additionally, butyrate modulates mucin expression, suggesting that SCFA are influential in increasing the synthesis and secretion of colonic mucin. In conclusion, bioactive peptides, fibres and SCFA appear to be liable nutrients to induce mucus secretion. New researches are required to determine whether they can be used to achieve preventive or therapeutic effects in human.
Keywords: Mucin, mucus, gut, milk bioactive factors, dietary fibre, short chain fatty acid
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