Dietary Fiber Ameliorates Lipopolysaccharide-Induced Intestinal Barrier Function Damage in Piglets by Modulation of Intestinal Microbiome

Abstract

Weaning of piglets is accompanied by intestinal inflammation, impaired intestinal barrier function, and intestinal microflora disorder. Regulating intestinal microflora structure can directly or indirectly affect intestinal health and host growth and development. However, whether dietary fiber (DF) affects the inflammatory response and barrier function by affecting the intestinal microflora and its metabolites is unclear. In this study, we investigated the role of intestinal microflora in relieving immune stress and maintaining homeostasis using piglets with lipopolysaccharide (LPS)-induced intestinal injury as a model. DF improved intestinal morphology and barrier function, inhibited the expression of inflammatory signal pathways (Toll-like receptor 2 [TLR2], TLR4, and NF-κB) and proinflammatory cytokines (interleukin 1β [IL-1β], IL-6, and tumor necrosis factor alpha [TNF-α]), and upregulated the expression of barrier-related genes (encoding claudin-1, occludin, and ZO-1). The contents of proinflammatory cytokines (IL-1β, IL-6, and TNF-α) and the activity of diamine oxidase in plasma were decreased. Meanwhile, DF had a strong effect on the composition and function of intestinal microflora at different taxonomic levels, the relative abundances of cellulolytic bacteria and anti-inflammatory bacteria were increased, and the concentrations of propionate, butyrate, and total short-chain fatty acids (SCFAs) in intestinal contents were increased. In addition, the correlation analysis also revealed the potential relationship between metabolites and certain intestinal microflora, as well as the relationship between metabolites and intestinal morphology, intestinal gene expression, and plasma cytokine levels. These results indicate that DF improves intestinal barrier function, in part, by altering intestinal microbiota composition and increasing the synthesis of SCFAs, which subsequently alleviate local and systemic inflammation. IMPORTANCE Adding DF to the diet of LPS-challenged piglets alleviated intestinal and systemic inflammation, improved intestinal barrier function, and ultimately alleviated the growth retardation of piglets. In addition, the addition of DF significantly increased the relative abundance of SCFA-producing bacteria and the production of SCFAs. We believe that the improvement of growth performance of piglets with LPS-induced injury can be attributed to the beneficial effects of DF on intestinal microflora and SCFAs, which reduced the inflammatory response in piglets, improving intestinal barrier function and enhancing body health. These research results provide a theoretical basis and guidance for the use of specific fiber sources in the diet to improve intestinal health and growth performance of piglets and thus alleviate weaning stress. Our data also provide insights for studying the role of DF in regulating gastrointestinal function in human infants.

Influence of Sodium Humate on the Growth Performance, Diarrhea Incidence, Blood Parameters, and Fecal Microflora of Pre-Weaned Dairy Calves

“…The results of this study found that the administration of 5 g of NaH reduced the serum IL-6 and TNF-α concentrations in pre-weaned calves, indicating the underlying anti-inflammatory activity of NaH. In addition, the body’s antioxidant defense levels are another important indicator for health status [ 38 ]. Changes in the diet or environment of animals can result in oxidative stress [ 39 ].…”

Organic Acids Improve Growth Performance with Potential Regulation of Redox Homeostasis, Immunity, and Microflora in Intestines of Weaned Piglets

“…The gastrointestinal tract is particularly susceptible to weanling stress, which can impair gastrointestinal morphology, permeability, and function [ 38 ]. Notably, both of the acidifiers prevented the fragmentation of villi, and slight vacuolar degeneration of epithelial cells in the ileum (day 14) and jejunum (day 49) were observed in the control group.…”

“…The chyme digestive enzyme activities were not affected by the two acidifiers, which was inconsistent with the previous report [ 45 ]. This discrepancy might be due to the different animal species, physiological stages, dietary structure, and composition of acidifiers [ 38 , 46 ].…”

“…Since gut microbes also play an active role in maintaining the intestinal health of weanling pigs [ 38 , 47 , 48 ], 16S rRNA gene sequencing technology was used to analyze and compare the cecal microbiota composition of the weaned pigs. Compared with the control, the abundance of predominant genera of Blautia was increased and YRC22 was decreased in both OA1 and OA2, while Dorea and Eubacterium in OA1 and Subdoligranulum in OA2 were decreased and Bulleidia in OA2 was increased at days 14 and/or 49.…”

Phenotyping of Fecal Microbiota of Winnie, a Rodent Model of Spontaneous Chronic Colitis, Reveals Specific Metabolic, Genotoxic, and Pro-inflammatory Properties

“…Among Eubacterium species, it may also be worth to note the ability of E. coprostanoligenes to carry out the conversion of cholesterol to the poorly absorbed sterol coprostanol [32]. It is rather surprising to find prevalence in WN mice of cellulolytic and butyrate-producing bacteria, generally associated with a diet based on vegetables rich in fibers and a healthy state of the intestinal microenvironment [33][34][35]. Wide evidence emphasized that butyrate-producing bacteria establish positive metabolic interactions with the intestinal cells.…”