Figure 2.

Effects of exposure to microbiota-derived metabolites. (a) Commensal formylated MAMPs recognized by the FPR-2 can inhibit the NFkB pathway, downregulating the production of inflammatory cytokines such as TNF-α, IL-1β, IL-6, and IL-8. These MAMPs can also induce the production of anti-inflammatory cytokines such as IL-10 and TGF-β. (b) Commensal PSA can inhibit intestinal inflammation by the TLR2 pathway in intestinal epithelial cells or the TCR pathway in T cells. (c) Commensal PSA and SLPs can stimulate T cell FOXP3 expression, promoting their polarization to Tregs and the production of anti-inflammatory cytokines. (d) Commensal AhR ligands can also modulate inflammation by regulating FOXP3-related gene expression directly. Created with Biorender.com.