Deoxynivalenol and E.coli lipopolysaccharide alter epithelial proliferation and spatial distribution of apical junction proteins along the small intestinal axis

We investigated a proposed synergistic effect of deoxynivalenol (DON) and lipopolysaccharides (LPS) on small intestinal architecture and epithelial barrier integrity in pigs. Crypt depth and intestinal cell proliferation were analyzed, as well as expression of zonula occludens protein-1 (ZO-1) and β-catenin of the apical junction complex along the small intestine. Barrows (26.2±4.1 kg) were fed restrictedly either a control diet (CON) or a diet naturally contaminated with 3.1 mg DON/kg feed (DON) for 37 d. At d 37, the control group was infused for 1 h either with 100 μg/kg BW of DON (CON-DON, n=6), 7.5 μg/kg BW of LPS (CON-LPS, n=6), a combination of both (CON-DON+LPS, n=7), or 0.9% NaCl (CON-CON, n=6) and the DON group with 7.5 μg/kg BW of LPS (DON-LPS, n=8) or 0.9% NaCl (DON-CON, n=6). Pigs were euthanized 3.25 h after start of infusion. Immunohistochemistry (5'-bromo-2'-deoxyuridine for proliferation) and immunofluorescence (ZO-1 and β-catenin) from duodenum, proximal jejunum, mid-jejunum, proximal ileum, and terminal ileum were analyzed for crypt depth, cell proliferation, and apical junction proteins. Duodenal crypts were deeper compared with the other 4 intestinal regions, and proximal jejunal crypts were deeper than those of mid-jejunum and proximal ileum (P