佐剂关节炎大鼠滑膜血管新生与VEGF/PI3K/AKT信号通路相关性研究

Research on correlativity between synovium neovascularization and VEGF/PI3K/AKT signaling pathway in rats with adjuvant arthritis

目的:研究佐剂性关节炎(AA)大鼠滑膜血管新生与血管内皮生长因子(VEGF)/磷脂酰肌醇3-激酶(PI3K)/丝-苏氨酸蛋白激酶(AKT)信号通路的相关性。方法:选取30只SD大鼠随机分为正常组和模型组各15只,将模型组大鼠采用弗氏完全佐剂注射致炎,建成AA大鼠模型,观察大鼠关节炎指数(AI)与足跖肿胀度(E),采用免疫组化法测定滑膜微血管密度MVD,电镜下观察血管内皮细胞超微结构,采用ELISA法测定血清白细胞介素-1(IL-1)水平,实时荧光定量PCR检测滑膜组织缺氧诱导因子-1α(HIF-1α)、VEGF水平,采用WB法检测滑膜组织PI3K、AKT蛋白的表达。结果:与正常组相比,模型组大鼠E、AI增高,滑膜组织MVD、VEGF、HIF-1α、PI3K、AKT及血清IL-1水平增加(P﹤0.01)。相关性分析显示PI3K与足趾肿胀度、关节炎指数、IL-1、HIF-1α、VEGF呈正相关(P﹤0.05);AKT与足趾肿胀度、IL-1、VEGF呈正相关(P﹤0.01);VEGF与MVD、HIF-1α呈正相关(P﹤0.01);HIF-1α与关节炎指数、MVD、PI3K呈正相关(P﹤0.05)。结论:VEGF/PI3K/AKT信号通路参与AA大鼠滑膜血管新生过程,VEGF介导PI3K/AKT信号通路的过表达可能是AA大鼠滑膜血管新生的作用机制之一。

Objective:To research the correlativity between synovium neovascularization and vascular endothelial growth factor(VEGF)/phosphatidylinositol 3-kinase(PI3K)/Serine-threonine protein kinase(AKT)signaling pathway in rats with adjuvant arthritis(AA).Methods:30 SD rats were selected and randomly divided into normal group and model group,15 rats in each group.The rats in model group were inflamed by injection of complete Freund's adjuvant and established into AA rat models.The arthritis index(AI)and plantar swelling(E)of rats were observed.The synovium microvessel density MVD was measured by immunohistochemical method.The ultramicrostructure of vascular endothelial cell was observed under electron microscope.The level of serum interleukin-1(IL-1)was measured by ELISA.The levels of hypoxia inducible factor-1α(HIF-1α)in synovium tissue was detected by realtime fluorescence quantitative PCR.The expressions of PI3K and AKT protein in synovial tissue was detected by WB method.Results:Compared with normal group,E and AI of rats in model group were increased;MVD,VEGF,HIF-1α,PI3K and AKT in synovium tissue and serum IL-1 level were increased in model group(P﹤0.01).The correlative analysis showed that PI3K was positively correlated with toe swelling,arthritis index,IL-1,HIF-1αand VEGF(P﹤0.05);AKT was positively correlated with toe swelling,IL-1 and VEGF(P﹤0.01);VEGF was positively correlated with MVD and HIF-1α(P<0.01);HIF-1αwas positively correlated with arthritis index,MVD and PI3K(P﹤0.05).Conclusion:VEGF/PI3K/AKT signaling pathway is involved in synovial neovascularization of AA rats.The overexpression of VEGF-mediated PI3K/AKT signaling pathway may be one of the mechanisms of synovial neovascularization in AA rats.