Paeoniflorin inhibits lipopolysaccharide-induced inflammation in LO2 cells by regulating RhoA/NLRP3 pathway

摘要

Background:Inflammation is an essential component of liver diseases.Paeoniflorin(PF),a monoterpenoid component derived from peony root(Paeonia lactiflora Pall.),has anti-inflammatory,immunoregulatory,and hepatoprotective activities.However,whether PF affects liver inflammation and its underlying mechanisms is unclear.In this study,we investigated the effects of PF on lipopolysaccharide(LPS)-induced inflammation in LO2 cells and the underlying molecular mechanism.Methods:LPS was used to induce inflammation.After PF pretreatment for 2 h,the cells were treated with PF and LPS.Cell counting kit-8 was used to measure cell viability.Tumor necrosis factor-a(TNF-a)and interleukin(IL)-6 were tested by Enzyme-linked immunosorbent assay.Western blot was used to evaluate TNF-a,Ras homolog family member A(RhoA),NOD-,LRR-and pyrin domain-containing protein 3(NLRP3),apoptosis-associated speck-like protein containing a CARD(ASC),caspase-1,and IL-1b proteins expression.Results:In LPS-induced LO2 cells,PF reduced TNF-a and IL-6 inflammatory cytokine production in a dose-dependent manner.LPS-induced TNF-a expression was also suppressed by PF.In addition,PF significantly inhibited LPS-induced RhoA activation(P=.0014).Finally,PF suppressed LPS-induced NLRP3 inflammasome activation by downregulating NLRP3,ASC,caspase-1,and IL-1b expression.Conclusion:These findings suggest that PF alleviates inflammation induced by LPS and further suggest the anti-inflammatory effect of PF may follow via reduced RhoA and NLRP3 inflammasome activity.