Hydrolyzed casein influences intestinal mucin gene expression in the rat

J Agric Food Chem. 2008 Jul 23;56(14):5572-6. doi: 10.1021/jf800080e. Epub 2008 Jun 18.


The effect of hydrolyzed casein (HC) on the expression of three mucin genes (Muc2, Muc3, and Muc4) in the rat intestine was investigated using quantitative real-time polymerase chain reaction. After a 10 day acclimatization period, rats received for 8 days the test diets containing either HC or a synthetic amino acid (SAA) mixture as the sole source of nitrogen or a protein-free (PF) diet (n = 12 per treatment). The addition of HC or the SAA mixture to the diet significantly improved average daily gain, average daily food intake, and gain:feed ratio as compared with the PF diet. Terminal ileal endogenous N flow was significantly higher for the HC-fed rats in comparison with either the SAA or the PF rats (p < or = 0.001). HC supported a significant increase of Muc3 mRNA (277 and 229% of that for diets PF and SAA, respectively; p < or = 0.05) in the small intestinal tissue and Muc4 mRNA (325 and 265% of that for diets PF and SAA, respectively; p < or = 0.05) in the colon. In conclusion, HC enhances ileal endogenous N flow and up-regulates in vivo the expression of some individual mucin genes.

MeSH terms

  • Animals
  • Caseins / administration & dosage
  • Caseins / pharmacology*
  • Diet
  • Gene Expression / drug effects*
  • Hydrolysis
  • Intestinal Mucosa / metabolism*
  • Intestines / chemistry
  • Male
  • Mucins / genetics*
  • RNA, Messenger / analysis
  • Rats
  • Rats, Sprague-Dawley


  • Caseins
  • Mucins
  • RNA, Messenger