Active or Autoclaved Akkermansia muciniphila Relieves TNF-α-Induced Inflammation in Intestinal Epithelial Cells Through Distinct Pathways

Intestinal inflammation is a major threat to the health and growth of young animals such as piglets. As a next-generation probiotics, limited studies have shown that Akkermansia muciniphila could alleviate inflammation of intestinal epithelial cells (IECs). In this study, a TNF-alpha-induced inflammatory model of IPEC-J2 cells, the intestinal porcine enterocytes, was built to evaluate the effects of active or inactive A. muciniphila on the inflammation of IECs. The viability of IPEC-J2 cells was the highest when treated with active (10(8) copies/mL) or inactive (10(9) copies/mL) A. muciniphila for 7.5 h (P < 0.01). Treated with 20 ng/mL of TNF-alpha and followed by a treatment of A. muciniphila, the mRNA level of proinflammatory cytokines (IL-8, IL-1 beta, IL-6 and TNF-alpha) was remarkably reduced (P < 0.05) along with the increased mRNA level of tight junction proteins (ZO-1 and Occludin, P < 0.05). Flow cytometry analysis showed that active or inactive A. muciniphila significantly suppressed the rate of the early and total apoptotic of the inflammatory IPEC-J2 cells (P < 0.05). According to results of transcriptome sequencing, active and inactive A. muciniphila may decline cell apoptosis by down-regulating the expression of key genes in calcium signaling pathway, or up-regulating the expression of key genes in cell cycle signaling pathway. And the bacterium may alleviate the inflammation of IECs by down-regulating the expression of PI3K upstream receptor genes. Our results indicate that A. muciniphila may be a promising NGP targeting intestinal inflammation.

Automated summary

Akkermansia muciniphila has shown potential in alleviating intestinal inflammation by reducing proinflammatory cytokines and increasing tight junction protein gene levels in porcine enterocytes, indicating its promise as a next-generation probiotics in targeting intestinal inflammation.