The Anti-Inflammatory Effect and Intestinal Barrier Protection of HU210 Differentially Depend on TLR4 Signaling in Dextran Sulfate Sodium-Induced Murine Colitis.
Ulcerative colitis (UC) is strongly associated with inflammation and intestinal barrier disorder. The nonselective cannabinoid receptor agonist HU210 has been shown to ameliorate inflamed colon in colitis, but its effects on intestinal barrier function and extraintestinal inflammation are unclear. To investigate the effects and the underlying mechanism of HU210 action on the UC in relation to a role of TLR4 and MAP kinase signaling. Wild-type (WT) and TLR4 knockout (Tlr4 Upon DSS challenge, mice suffered from bloody stool, colon shortening, intestinal mucosa edema, pro-inflammatory cytokine increase and intestinal barrier destruction with goblet cell depletion, increased intestinal microflora accompanied with elevated plasma lipopolysaccharide, reduced mRNA expression of the intestinal tight junction proteins, and abnormal ratio of CD4 Our study indicates that in experimental colitis, HU210 displays a protective effect on the intestinal barrier function independently of the TLR4 signaling pathway however, in the extraintestinal tissues, the anti-inflammatory action seems through affecting TLR4-mediated p38 mitogen-activated protein kinase pathway.