北五味子多糖通过ERK1/2通路对AngⅡ诱导的心肌成纤维细胞增殖的作用机制

Mechanism of Polysaccharide of Schisandra chinensis on Inhibiting Cardiac Fibroblasts Proliferation Induced by Angiotensin Ⅱ by Extracellular Regulated Protein Kinase 1/2 Pathway

目的观察北五味子多糖(polysaccharide of Schisandra chinensis,SCP)对血管紧张素Ⅱ(AngiotensinⅡ,AngⅡ)诱导的心肌成纤维细胞(CFb)增殖作用,并探讨其作用机制.方法以培养的新生Wistar大鼠乳鼠CFb为实验模型,实验分为对照组、模型组、3个药物剂量组.采用胰酶消化、差速贴壁法培养CFb;四氮唑盐(MTT)比色法检测CFb增殖;羟脯氨酸(Hyp)法测定胶原含量;分光光度计测定CFb中超氧化物歧化酶(SOD)活力、丙二醛(MDA)水平;硝酸还原酶法和分光光度法分别测定不同干预条件下CFb培养液中一氧化氮合酶(NOS)活性及一氧化氮(NO)水平;免疫组化技术检测CFb中细胞外调节蛋白激酶(ERK1/2)蛋白表达.结果SCP能够显著抑制AngⅡ诱导的CFb增殖(P<0.05或P<0.01),降低Hyp含量,提高SOD活力,降低MDA水平(P<0.05,P<0.01),提高NOS活性及NO水平(P<0.05,P<0.01),减低ERK1/2蛋白表达(P<0.05,P<0.01).结论SCP可通过抑制ERK1/2信号通路提高NOS活性,并升高NO水平,增强抗AngⅡ诱导的CFb增殖能力.

Objective To investigate the effect of polysaccharide of Schisandra chinensis(SCP)on the proliferation of cardiac fibroblasts induced by angiotensin(AngⅡ)and its mechanism.Method CFb of neonatal Wistar rats was used as the experimental model.The rats were divided into control group,model group and drug administration group.The cells were digested by trypsin,then cultured with differential adhesion method,and the proliferation of CFb was detected by MTT colorimetry.The content of collagen was measured by hydroxyproline method,the activity of superoxide dismutase(SOD)and the level of malondialdehyde(MDA)in CFb were measured by spectrophotometer.Nitrate reductase method and spectrophotometry were used to determine the activity of nitric oxide synthase(NOS)and the level of nitric oxide(NO)together with ERK1/2 protein expression by immunohistochemical technique in CFb medium under different SCP intervention.Results CFb proliferation induced by AngⅡwas significantly inhibited by SCP(P<0.05 or P<0.01),Hyp content decreased,SOD activity increased,MDA level decreased(P<0.05,P<0.01),NOS activity and NO level increased(P<0.05,P<0.01);ERK1/2 protein expression decreased(P<0.05,P<0.0 1).Conclusion SCP can increase NOS activity and NO level by inhibiting ERK1/2 pathway,improve the ability of scavenging free radical to inhibit the proliferation of CFb induced by AngⅡ.