Reduction in Mucosal Barrier Markers with Soy Protein Diet but not Lactobacillus rhamnosus GG in DSS-Treated Mice
The incidence of inflammatory bowel diseases (IBD) increased recently. Within the colon, the family of mucins and trefoil factors (TFF) facilitate mucosal protection. Our objective was to determine if diet and/or administration of LGG would attenuate DSS-induced colitis by altering expression of the MUC and TFF genes. C57BL/6 mice were fed diets containing casein, soy, or whey protein with or without LGG for 12 days. Seven days after LGG, the mice were given 2% DSS for 4 days. One day after DSS treatment the colonic and cecal tissues and fecal samples were collected and analyzed by quantitative RT-PCR. Whey protein significantly increased cecal LGG content. MUC1 expression was induced by DSS and soy protein dramatically suppressed it. TFF3 was upregulated by DSS and decreased by soy and whey protein. Soy protein also reduced the inflammatory scores, TNF-α and prevented colon shortening. LGG did not have effect on these parameters. In conclusion, soy protein suppressed the DSS-induced inflammatory stimulation of MUC, TFF and TNF-α gene expression. Whey protein may act as prebiotic, but failed to prevent colitis.