脂联素对内皮祖细胞增殖和迁移能力的影响

目的研究脂联素通过磷酸肌醇3激酶/蛋白激酶B(Akt)通路改善内皮祖细胞(EPC)增殖、迁移能力的影响并探讨其可能机制。方法利用密度梯度离心法分离、培养人外周血单个核细胞,将EPC分为对照组、脂联素组(10μg/ml)、磷酸肌醇3激酶抑制剂干预组(干预1组)和细胞外信号调节蛋白激酶(ERK)抑制剂干预组(干预2组)。采用四唑盐比色法、细胞集落形成单位计数等方法观察各组EPC增殖能力的变化情况,应用transwell小室法分析EPC迁移能力,采用免疫蛋白印迹法观察脂联素处理EPC后,Akt、磷酸化Akt、ERK、磷酸化ERK的表达情况。结果脂联素组EPC增殖能力较对照组明显提高(P<0.05),干预1组EPC增殖、迁移效应较脂联素组明显抑制(P<0.05),而干预2组对EPC增殖、迁移改善效应无明显影响。与对照组比较,脂联素组磷酸化Akt表达明显增加,干预1组磷酸化Akt表达及脂联素组磷酸化ERK表达无明显增加。结论脂联素具有促进EPC增殖、迁移等功能活性的作用,其主要机制可能与磷酸肌醇3激酶/Akt信号通路激活有关。

Effect of adiponectin on proliferation and migration of endothelial progenitor cells

Objective To study the effect of adiponectin on proliferation and migration of endothelial progenitor cells(EPC) through the PI3K/Akt pathway and its possible mechanism.Methods Cultured EPC isolated from human peripheral mononuclear cells by density gradient centrifugation were divided into control group,adiponectin(10μg/ml) treatment group,PI3K inhibitor treatment group and extracellular signal regulation kinase(ERK) inhibitor treatment group.Proliferation of EPC was observed in different groups by tetrazole colorimetry,colony forming unit counting and MTT assay,respectively.Migration of EPC was analyzed by transwell chamber assay. Expressions of Akt,p-Akt,ERK and p-ERK in adiponectin-treated EPC were detected by Western blot.Mechanism underlying the effect of adiponectin on proliferation and migration of EPC was studied.Results The proliferation activity of EPC was significantly higher in adiponectin treatment group than in control group(P<10.05).The proliferation and migration activities of EPC were significantly lower in PI3K inhibitor treatment group than in adiponectin treatment group(P<0.05).However,no significant difference was found in proliferation and migration activities of EPC between ERK inhibitor treatment group and adiponectin treatment group(P>0.05).The expression level of p-Akt was significantly higher in adiponectin treatment group than in control group(P<0.05).However,no significant difference was found in expression of p-Akt and p-ERK between PI3K inhibitor treatment group and adiponectin treatment group(P>0.05). Conclusion Adiponectin promotes the proliferation and migration of EPC by activiating the PI3K/Akt pathway.