Probiotic administration aggravates dextran sulfate sodium salt-induced inflammation and intestinal epithelium disruption in weaned pig.

Background: A. muciniphila (AKK) has attracted extensive research interest as a potential next-generation probiotics, but its role in intestinal pathology is remains unclear. Herein, this study was conducted to investigate the effects of A. muciniphila DSM 22,959 on growth performance, intestinal barrier function, microecology and inflammatory response of weaned piglets stimulated by dextran sulfate sodium salt (DSS).

Method: Twenty-four Duroc × Landrace × Yorkshire (DLY) weaned piglets used for a 2 × 2 factorial arrangement of treatments were divided into four groups with six piglets in each group. From 1 to 15 d, the CA and DA groups were orally fed with 1.0 × 10¹¹ colony-forming units A. muciniphila per day, while the CON and DCON groups were received gastric infusion of anaerobic sterile saline per day. The pigs were orally challenged (DCON, DA) or not (CON, CA) with DSS from day 9 to the end of the experiment and slaughtered on day 16.

Results: Presence of A. muciniphila in DSS-challenged weaned pigs resulted in numerically increased diarrhea rate, blood neutrophilic granulocyte, serum C-reactive protein and immunoglobulin M levels, and numerically reduced final weight, average daily feed intake and average daily gain. The decrease in intestinal villus height, villous height: crypt depth ratio and digestibility was accompanied by lower expression of ZO1, ZO2, Claudin1, DMT1, CAT1, SGLT1 and PBD114 genes, as well as decreased enzyme activities of intestinal alkaline phosphatase, lactase, sucrase and maltase of piglets in DA group compared to piglets in DCON group. The abundance of Bifdobacterium, Lactobacillus, A. muciniphila, Ruminococcus gnavus was numerically higher in digesta of pigs in DA group than those in DCON group. The inflammatory responses of piglets were dramatically changed by the simultaneous presence of A. muciniphila and DSS: expression level of IL17A, IL17F, IL23, RORγt, Stat3 was elevated in DA pigs compared to the other pig groups.

Conclusions: Our result showed that the oral A. muciniphila aggravates DSS-induced health damage of weaned piglet, which may attribute to the deteriorating intestinal morphology, dysbiosis of microbiota and inflammatory response disorders.