Neoglycoconjugates of caseinomacropeptide and galactooligosaccharides modify adhesion of intestinal pathogens and inflammatory response(s) of intestinal (Caco-2) cells

Abstract

Dietary glycoconjugates may constitute new food ingredients with the potential ability to inhibit pathogen infection by blocking or competing for bacterial adhesion sites in intestinal cells. In this study, galactooligosaccharides, obtained from transgalactosylation of lactose (GOS-La) or lactulose (GOS-Lu), were used for the glycation of caseinomacropeptide hydrolysates (hCMP). The effects of these compounds on Salmonella enterica CECT 443 and Listeria monocytogenes CECT 935 adhesion, induction of inflammatory cytokines production, and >toll-like> (TLR)-2/4 and chemokine CXCR3 receptor expression (mRNA) in intestinal epithelial (Caco-2) cells were evaluated. hCMP:GOS-La or hCMP:GOS-Lu significantly reduced pathogen adhesion. GOS-Lu and hCMP:GOS-Lu inhibited the production of IL-1β by intestinal cells stimulated by the pathogens tested, but this effect was not exerted by GOS-La and hCMP:GOS-La. However, the effect of GOS-Lu and hCMP:GOS-Lu was more discrete on the L. monocytogenes-mediated production of TNFα not affecting the production of TNFα in cultures exposed to S. enterica. hCMP:GOS-Lu increased TLR4 and CXCR3 expression levels of cells exposed to S. enterica CECT 443 suspensions, but down-regulated the expression of TLR2/4 and CXCR3 suggesting the complete blockage of L. monocytogenes CECT 935 interaction with intestinal cells.