罗格列酮保护氧糖剥夺复氧PC12细胞通过减少HMGB1释放和上调DUSP

Rosiglitazone protect PC12 cells against oxygen-glucose deprivation/reoxygenation through HMGB1 reduction and DUSP8 upregulation

目的探讨罗格列酮(rosiglitazone,RGZ)对氧葡萄糖剥夺/复氧处理后大鼠肾上腺髓质嗜铬细胞瘤(PC12)细胞的保护作用及机制。方法建立氧葡萄糖剥夺/复氧细胞模型,给予不同浓度罗格列酮及PPAR-γ特异性抑制剂GW9662,MTT法检测细胞存活率;ELISA法检测高迁移率族蛋白B1(HMGB1)浓度;Western blot法检测双特异性蛋白磷酸酶8(Dual-specificity Phosphotase,DUSP8)、Bcl-xl、PPARγ以及RAGE蛋白表达水平。结果OGD10h/R24 h后,DUSP8、Bcl-xl及PPARγ蛋白水平明显降低,RAGE和HMGB1水平明显增高(P<0.05);罗格列酮干预后,DUSP8、Bcl-xl及PPARγ蛋白水平明显增加,RAGE和HMGB1水平下降(P<0.05)。罗格列酮上调DUSP8、Bcl-xl及下调HMGB1、RAGE的作用可被GW9662有效抑制。结论罗格列酮通过上调PC12细胞OGD/R后的PPARγ蛋白表达,继而增加DUSP8和Bcl-xl抗凋亡蛋白的表达并减少晚期炎症介质HMGB1的分泌,是PPARγ激动剂保护氧糖剥夺复氧细胞的机制,PPARγ有望成为治疗脑缺血再灌注损伤的靶标。

Objective To investigate the mechanism of rosiglitazone protecting against oxygen glucose deprivation/reoxygenation(OGD/R)induced PC12 cells.Methods Establish the hypoxia-ischemia and reperfusion cell model.Different concentrations of rosiglitazone and PPAR-γinhibitor GW9662 were administrated to the OGD/R induced PC12 cells.Cell viability were assessed by MTT assay.HMGB1 level was assessed by ELISA.The protein expression of DUSP8、Bcl-xl、PPARγand RAGE were examined by western blot.Results Western blot showed in OGD10 h/R24 h induced PC12 cell model,the levels of DUSP8、Bcl-xl and PPARγwere decreased,but the levels of RAGE protein were increased significantly.In addition,results from ELISA analysis indicated that after OGD10 h/R24 h,HMGB1 levels increased sharply.While after rosiglitazone treatment,the protein expression of DUSP8,Bcl-xl and PPARγincreased,RAGE and HMGB1 protein levels decreased significantly.In contrast,the upregulation of PPARγ、Bcl-xl and DUSP8 protein as well as downregulation of RAGE protein and HMGB1 could be remarkably suppressed by specific antagonist GW9662.Conclusion This study suggested that rosiglitazone might increase the expression of DUSP8 and Bcl-xl as well as decrease HMGB1 secretion in OGD/R induced PC12 cells through upregulation of PPARγprotein,it might be due to the mechanism of rosiglitazone protection effect on OGD/R induced neuronal cells.Thus,PPARγshould be expected to be the molecular pharmacology targets against cerebral ischemia and reperfusion injury.