Roles and mechanisms of complement 5a and complement 5a receptor in palmitic acid induced microglia inflammation / 实用医学杂志

ABSTRACT

Objective To observe the effect of complement 5a receptor(C5aR)antagonist(PMX53)and palmitic acid(PA)on the inflammatory reaction of microglia,and to investigate the roles and mechanisms of com-plement C5a-C5aR in PA induced microglia inflammation.Methods Microglia from one day old mice was collect-ed,purified and identified by primary culture and immunohistochemical staining,and then was randomly divided into three groups including PA group,PA+PMX53 group and control group.The expressions of tumor necrosis factor-α(TNF-α),Iba-1 and ERK1/2 were determined by ELISA,Western blot and QT-PCR.Results In PA group, the levels of Iba-1 and TNF-α were higher significantly than the control group(P<0.001).Similarly,the levels of ERK1/2 mRNA(P = 0.005 6)and p-ERK1/2 protein(P < 0.001)in the PA group were higher significantly than that in control group in spite of no difference in ERK1/2 protein in all groups. However,the levels of Iba-1,p-ERK1/2 protein,ERK1/2 mRNA and TNF-α in the PA+PMX53 group were significantly lower than that in the PA group(P<0.001),although there was no difference in ERK1/2 protein in all groups.Conclusions C5a receptor antagonist suppresses inflammatory reaction of microglia induced byPA,suggesting that C5a-C5aR-ERK may par-ticipate in the inflammation of microglia induced byPA. Therefore,C5a receptor antagonist may protect the brain tissues from inflammation-induced damage.