热休克蛋白90在氯化钴对抗血清-葡萄糖剥夺引起的心肌细胞损伤中的作用

目的观察氯化钴(CoCl2)对血清-葡萄糖剥夺(SGD)诱导的H9c2心肌细胞损伤的影响,探讨热休克蛋白90(HSP90)在其中的作用。方法用SGD的方法处理H9c2心肌细胞,建立缺血性损伤的心肌细胞模型。在SGD过程中同时给予CoCl2处理;在应用SGD和CoCl2之前给予HSP90抑制剂(17-AAG)预处理。处理结束后,检测细胞存活率、HSP90的表达、细胞内活性氧(ROS)以及线粒体膜电位(ΔΨm)。结果 SGD处理可引起H9c2心肌细胞损伤,表现为细胞存活率降低、胞内ROS水平升高及ΔΨm丢失。SGD处理还可降低H9c2心肌细胞内HSP90的表达。在50～100μmol.L-1浓度范围内,CoCl2处理可保护H9c2心肌细胞对抗SGD引起的存活率降低,100μmol.L-1CoCl2还可对抗SGD引起的ROS水平升高和ΔΨm丢失。100μmol.L-1CoCl2可时间依赖性地促进胞内HSP90的表达。在50～200μmol.L-1浓度范围内,CoCl2处理可对抗SGD诱导的HSP90表达下调,其中100μmol.L-1的CoCl2具有最强的拮抗作用。17-AAG通过抑制HSP90的作用可明显减弱CoCl2诱导的上述心肌细胞保护作用。结论 CoCl2可保护H9c2心肌细胞对抗SGD引起的损伤,其机制之一与上调HSP90表达有关。

Roles of heat shock protein 90 in the protection of CoCl2 against serum & glucose deprivation-induced injury in H9c2 cellsHE Jin-lian1,DONG Qi2,LIN Chun-xi3,ZHANG Mei4,

Aim To investigate the effect of cobalt chloride(CoCl2) on serum & glucose deprivation(SGD)-induced injury and explore the role of HSP90 in the protection of CoCl2 in H9c2 cells.Methods H9c2 cells were subjected to SGD to establish a cellular model of cardiac ischemia.CoCl2 was co-administered with SGD.17-AAG(a selective HSP90 inhibitor) was administered before exposure of cells to CoCl2 and SGD.Cell viability,HSP90 expression,intercellular reactive oxygen species(ROS) as well as mitochondrial membrane potential(ΔΨm) were observed.Results H9c2 cells exposure to SGD induced insults,including decreased cell viability,increased ROS level and a ΔΨm loss.SGD exposure downregulated the expression of HSP90 in H9c2 cells.At concentrations ranging from 50 to 100 μmol·L-1,treatment with CoCl2 antagonized SGD-induced decrease in cell viability.CoCl2(100 μmol·L-1) treatment also attenuated ROS accumulation and ΔΨm loss caused by SGD.Furthermore,exposure of H9c2 cells to 100 μmol·L-1 CoCl2 upregulated HSP90 expression in a time-dependent manner.At concentrations from 50 to 200 μmol·L-1,treatment with CoCl2 attenuated the downregulation of HSP90 induced by SGD,among which 100 μmol·L-1 CoCl2 was the most effective.Inhibition of HSP90 by 17-AAG abrogated CoCl2-induced cardioprotection in H9c2 cells.Conclusion CoCl2 protects H9c2 cells against SGD-induced insults partially by upregulation of HSP90 expression.