热休克蛋白A12B降低脂多糖诱导的血管内皮细胞通透性

目的 探讨脂多糖诱导下血管内皮细胞热休克蛋白A12B(HSPA12B)表达的改变及其对血管内皮通透性的影响.方法 体外传代培养人脐静脉内皮细胞,并将其分为空白组(未进行任何处理)、脂多糖(1 μg/mL)诱导组、脂多糖+HSPA12B高表达组(转染HSPA12B过表达质粒)和脂多糖+阴性质粒对照组(转染阴性对照质粒).采用电阻抗检测仪检测脐静脉内皮细胞的跨内皮电阻抗,流式细胞仪检测血管内皮钙黏素(VE-cadherin)的表达,蛋白质印迹、PCR检测HSPA12B的表达改变.结果 脐静脉内皮细胞经脂多糖诱导后,细胞中HSPA12B表达在0～12 h内上调,12 h时达高峰.HSPA12B能使脐静脉内皮细胞的跨内皮电阻抗值明显升高(P＜0.001),并能完全对抗脂多糖诱导造成的跨内皮电阻抗值的下降(P＜0.001).HSPA12B能使脐静脉内皮细胞细胞膜上VE-cadherin的表达上调.结论 HSPA12B可能通过上调VE-cadherin表达降低血管内皮细胞的通透性,从而保护血管内皮的屏障功能.

Heat shock protein A12B decreases lipopolysaccharide-induced permeability of human umbilical vein endothelial cells

Objective To explore the dynamic expression changes of HSPA12B and its effect on permeability of HUVEC induced by lipopolysaccharide(LPS). Methods The HUVEC subcultured in vitro were divided into three groups: control group( without any treatment);LPS group(1ug/ml LPS);LPS+pIRES2-EGFP-HSPA12B-3Flag group(The HSPA12B gene overexpression plasmid was transiently transfected into HUVEC and then LPS of 1ug/ml was added);LPS pIRES2-EGFP-3Flag group(The negative control plasmid was transiently transfected into HUVEC and then LPS of 1ug/ml was added).The transendothelial electrical resistance(TEER) of HUVEC was measured by MERSST×01 Electrode.The expression of VE-cadherin was studied by flow cytometry. RT-PCR and western blot were used to detect the dynamic expression changes of HSPA12B of HUVEC stimulated by LPS at various times. Results Our study showed that after challenged by LPS,HSPA12B mRNA and protein was upregulated gradually ,peaked at 12h ,and then decreased .HSPA12B can make TEER value of HUVEC increased significantly, and can completely against the decline of TEER value induced by LPS.HSPA12B can cause the upregulation of expression of VE-cadherin . Conclusion HSPA12B can reduce the permeability Sof vascular endothelial cells by upregulating the expression of VE-cadherin , thus protecting vascular endothelial barrier function.