Dietary deoxynivalenol and oral lipopolysaccharide challenge differently affect intestinal innate immune response and barrier function in broiler chickens1

Abstract

Dietary deoxynivalenol (DON) impairs the intestinal immune system and digestive functions of broiler chickens. However, little is known whether increasing doses of DON similarly affect the intestinal functions in different segments of the small intestine in chickens and whether a second oral challenge may potentiate those effects. The present objective was to investigate the effect of increasing dietary DON concentrations on the relative expression of genes for tight junction proteins, mucins, toll-like receptors (TLR), and cytokines in duodenum and jejunum, jejunal mucosal permeability, as well as on α-1acid glycoprotein and IgA in serum with or without an additional oral lipopolysaccharide (LPS) challenge. Eighty 1-d-old chickens were fed diets with increasing DON concentrations (0, 2.5, 5, and 10 mg DON/kg diet) for 5 wk. One day before sampling, half of the chickens received an oral challenge with 1-mg Escherichia coli O55:B5 LPS/ kg BW. Ussing chambers were used to measure the jejunal permeability in birds receiving 10-mg DON/kg feed with or without LPS challenge and 0-mg DON/kg feed without LPS. Increasing DON concentrations of up to 5-mg DON/kg increased (P < 0.05) the duodenal expression of TLR2, IL6, and Claudin 1 (CLDN1) by up to 84%, 88%, and 48%, respectively, compared with the noncontaminated diet. Likewise, jejunal CLDN1 expression increased up to 23% in the chickens fed DON concentrations of up to 5-mg DON/kg diet (P < 0.05). Moreover, increasing DON concentrations linearly and quadratically decreased (P < 0.05) the jejunal expression of TLR2 and transforming growth factor-β 1, respectively. The additional LPS challenge increased (P < 0.040) duodenal occludin expression by 10% as well as the jejunal tissue conductance in chickens of the 10 DON group (P = 0.050). In conclusion, dietary DON differently affected the duodenal and jejunal expression of genes for tight-junction proteins and proinflammatory signaling pathways. The additional LPS challenge did not potentiate the DON effect but it seemed to induce a certain up-regulation of the proinflammatory response in the duodenum and enhanced the mucosal permeability in the jejunum.

Effect of dietary fiber and threonine content on intestinal barrier function in pigs challenged with either systemic E. coli lipopolysaccharide or enteric Salmonella Typhimurium

“…The increase in total fecal mucin output with enteric ST inoculation agrees with a previous study that reported increased mucin secretion following immune stress in rats induced by live pathogenic E. coli [45]. Although there is some information indirectly relating the impact of immune stimulation on mucus secretion in pigs [53] and chickens [54], the present study demonstrates direct evidence that enteric Salmonella Typhimurium challenge increases mucus secretion. This contrasts the lack of fecal mucin output response in LPS challenged pigs reported here.…”

Nontoxic-dose deoxynivalenol aggravates lipopolysaccharides-induced inflammation and tight junction disorder in IPEC-J2 cells through activation of NF-κB and LC3B

“…2 ). These results suggested that the addition of nontoxic-dose DON could enhance the inflammatory response induced by LPS in IPEC-J2 cells, which were similar with earlier research that LPS combined with DON could induce a certain up-regulation of the proinflammatory response in the duodenum of broiler chickens ( Lucke et al, 2018 ). The NLRP3 inflammasome, a member of innate immune receptor NLR family which execute cellular inflammation processes, is expressed in gut epithelial cells and plays an important role in intestinal inflammation and infectious enteritis ( Hirota et al, 2011 ; Zmora et al, 2017 ).…”

Effect of Probiotics and Multi-Component Feed Additives on Microbiota, Gut Barrier and Immune Responses in Broiler Chickens During Subclinical Necrotic Enteritis

“…Lower relative abundance of Escherichia-shigella in the PPEO and PROB groups compared to PC was associated with the reduction of LPS biosynthesis, LPS biosynthesis proteins, and bacterial secretion system in PROB and PPEO groups compared to NC and PC as indicated by KEGG pathway. LPS induce mucosal immune responses (69); thus, such responses to the overgrowth of opportunistic bacteria due to the dysbiosis caused by NE challenge might have been attenuated by PROB and PPEO supplementation.…”