hexarelin的细胞保护作用研究

Cytoprotection Effect of Hexarelin

目的研究生长素释放肽hexarelin是否具有细胞保护作用。方法利用H2O2作用于RAW264.7巨噬细胞作为细胞氧化应激性损伤模型,以细胞活性(MTT法检测)、热休克蛋白70(HSP70)表达水平(Western blotting法检测)等指标判断细胞损伤及修复情况,观察不同浓度hexarelin预处理不同时间对上述细胞氧化应激性损伤的保护作用。结果与对照组相比,H2O2造成了明显的细胞氧化应激性损伤,细胞活性明显下降,HSP70蛋白表达水平似有升高,但与对照组相比无统计学差异;hexarelin预处理可剂量依赖性地减轻由H2O2所致的细胞活性下降,且这种作用在hexarelin 10-5mol/L、预处理2h对细胞的保护作用最强。单独用hexarelin预处理细胞后,HSP70的表达即明显升高。给予hexarelin预处理,再用H2O2刺激细胞,HSP70的水平进一步升高。结论 Hexarelin具有抗氧化应激和细胞保护作用,这种作用与其诱导HSP70的表达有关。

Objective To investigate whether hexarelin could exert antioxidant cytoprotection effects. Methods Using H202 to in- duce oxidative injury in RAW264.7 macrophage - like cells, we observed if hexarelin pretreatment （with different concentrations and times） could prevent cells against oxidative injury. Cell viability and proliferation were assayed by MTT, and the expression level of heat shock protein 70 （HSP＇/0） was evaluated by Western blotting. Results Compared with the control cell, H202 induced significant oxida- tive injury, as evidenced by a sharp drop in cell viability ; the protein expression level of H202 - challenged cells appeared higher than the control but did not show statistical significance. Pretreatment with hexarelin dose - dependently protected the H202 - induced decrease in cell viability, and this protection was the most significant when hexarelin was at 10-Smol/L and pretreatment for 2 hours. Hexarelin alone could increase the protein expression of HSP70 in RAW264.7 cells. Hexarelin pretreatment plus HzOz challenging further increased the HSP70 level. Conclusion Hexarelin could exert anti - oxidant cytoprotection effect, which is associated with the induction of HSP70 ex- pression.