Casein glycomacropeptide in the diet may reduceEscherichia coliattachment to the intestinal mucosa and increase the intestinal lactobacilli of early weaned piglets after an enterotoxigenicE. coliK88 challenge

Abstract

Casein glycomacropeptide (CGMP), a glycoprotein originating during cheese manufacture, has shown promising effects by promoting the growth of some beneficial bacteria in vitro, although its activity has not been well explored. The present study was designed to evaluate the effects of CGMP against enterotoxigenic Escherichia coli (ETEC) K88 in vitro (Trial 1) and in vivo (Trial 2). In Trial 1, increasing concentrations of CGMP (0, 0·5, 1·5 or 2·5 mg/ml) were tested regarding its ability to block the attachment of ETEC K88 to ileal mucosa tissues obtained from piglets. Increasing the concentration of CGMP resulted in a gradual decrease in ETEC K88 attachment to the epithelial surface. In Trial 2, seventy-two piglets were distributed in a 2 £ 2 factorial combination including or omitting CGMP in the diet (control diet v. CGMP) and challenged or not with ETEC K88 (yes v. no). Inclusion of CGMP increased crude protein, ammonia and isoacid concentrations in colon digesta. CGMP also increased lactobacilli numbers in ileum and colon digesta, and reduced enterobacteria counts in mucosa scrapings and the percentage of villi with E. coli adherence measured by fluorescence in situ hybridisation. The inclusion of CGMP in the diets of challenged animals also prevented the increase of enterobacteria in ileal digesta. We can conclude that CGMP may improve gut health by diminishing the adhesion of ETEC K88 to the intestinal mucosa, by increasing the lactobacilli population in the intestine and by reducing the overgrowth of enterobacteria in the digestive tract of piglets after an ETEC K88 challenge.Key words: Bovine glycomacropeptide: Piglets: Microbiota: Intestinal health Adherence of bacteria to the intestinal epithelium is known to be a prerequisite step for the colonisation and infection of the gastrointestinal tract by many pathogens. Some strains of pathogenic Escherichia coli have developed mechanisms of adhesion to intestinal (1) or renal cells (2) . In particular, enterotoxigenic E. coli (ETEC) strains adhere to receptors on the intestinal epithelium by proteinaceous surface appendages called fimbriae (3) . ETEC expressing the K88 fimbrial antigen is the most common pathogroup in young pigs (1) , and glycoproteins, sialoglycoproteins or glycosphingolipids are considered the main receptors for different K88 (ab, ac or ad) fimbrial variants (4 -7) .The potential of certain compounds to inhibit the adherence of micro-organisms, specifically E. coli, to the intestinal epithelium has been studied in vitro by various authors. Schwertmann et al. (8) and Shahriar et al. (9) described the potential of different milk glycoproteins to bind the fimbriae of E. coli and to inhibit the F4ac-positive E. coli attachment to intestinal villi in vitro. Naughton et al. (10) also described different types of prebiotics (non-digestible oligosaccharides) capable of reducing the numbers of E. coli in jejunal organ cultures of pigs. Some reports suggest that milk contains glycoconjugates that have structural homology to the glycan moi...

Novel Mechanisms Underlying the Therapeutic Effect of Glycomacropeptide on Allergy: Change in Gut Microbiota, Upregulation of TGF-β, and Inhibition of Mast Cells

“…Our results are consistent with the study of Chen et al [14], who used a small amount of GMP (0.1 mg/day), where the amount of Lactobacillus and Bifidobacterium was significantly increased in the fecal samples of mice. In addition, piglets receiving a diet supplemented with GMP over 15 days show increased lactobacilli numbers in the ileum and proximal colon [29], and mice chronically fed a GMP-enriched diet have a significant increase in Bacteroides in their feces compared to those fed a casein-enriched diet [30]. In a series of prospective studies analyzing differences in the composition of the intestinal flora between allergic and nonallergic infants, colonization with Bifidobacterium and Bacteroides during the first years of life appeared to be associated with protection against allergy [11,12,13].…”

Effects of casein glycomacropeptide supplementation on growth performance, intestinal morphology, intestinal barrier permeability and inflammatory responses in Escherichia coli K88 challenged piglets

“…In this study, K88 challenged piglets supplied with 1% CGMP showed a similar growth performance and fecal scores as control group, which suggested the ability of CGMP to alleviate the negative effect caused by K88 challenge. However, Hermes et al. (2013) reported that neither CGMP diet nor enterotoxigenic E. coli (ETEC) challenge had impact on growth performance or feed intake.…”

“…Regarding to the result of intestinal E. coli counts, it is interesting to remark that the amount of significant enterobacteria E. coli both in cecum and colon contents of CGMP treated group was not increased after K88 challenge. Several researches reported that less adhesion of K88 on intestinal mucosa or Caco-2 cells after CGMP treated ( Bruck et al., 2006 , Gonzalez-Ortiz et al., 2014 , Hermes et al., 2013 ). Hermes et al.…”

Evaluation of the Probiotic Strain Bifidobacterium longum subsp. Infantis CECT 7210 Capacities to Improve Health Status and Fight Digestive Pathogens in a Piglet Model

“…The DNA was eluted in 200 mL of Qiagen buffer AE and stored at −80°C until use. A SYBR green qPCR targeting the gene coding the F4 fimbria of E. coli K88 was performed according to the procedure described by Hermes et al (2013). Results are expressed as cfu/g of fresh matter (FM) and log of F4 gene copies/g FM.…”