PI3K/Akt通路在硫化氢后处理保护心肌细胞缺氧复氧损伤中的作用  

Role of PI3K/Akt pathway in protection of cardiomyocytes against hypoxia-reoxygenation injury induced by hydrogen sulfide post-conditioning

作　　者：李钢[1] 杨双强[1] 

机构地区：[1]重庆医科大学附属第一医院胸心外科,重庆400016

出　　处：《第三军医大学学报》2011年第17期1803-1807,共5页Journal of Third Military Medical University

摘　　要：目的探讨硫化氢后处理对原代培养的新生大鼠心肌细胞缺氧复氧损伤的保护作用及可能机制。方法以硫氢化钠(NaHS)作为外源性硫化氢供体。原代培养新生大鼠的心肌细胞随机分为5组:①正常对照组;②缺氧复氧组(hypoxia-reoxygenation,HR组);③二甲基亚砜组(dimethyl sulfoxide,DMSO组);④硫化氢后处理组(hydrogen sulfide post-con-ditioning,H2S组);⑤LY294002+H2S后处理组(LY+H2S组)。分别于缺氧前和复氧2 h检测各组的心肌细胞存活率、培养液中CK和LDH的活性;复氧末,用流式细胞学技术检测各组心肌细胞凋亡情况;Western blot检测HIF-1α、p-Akt与Akt蛋白的表达情况。结果通过比较可知,复氧2 h时,H2S组心肌细胞存活率较HR组升高显著[(71.55±1.46)%vs(62.03±1.29)%,P<0.01],CK、LDH活性以及心肌细胞凋亡率明显降低[(244.99±21.38)U/L vs(329.53±26.14)U/L,(371.64±18.62)U/L vs(427.69±13.25)U/L,(10.37±1.51)%vs(17.38±2.04)%,P<0.01];同时,HIF-1α和p-Akt蛋白表达水平明显升高[(63.93±4.64)%vs(41.82±6.14)%,(62.59±2.11)%vs(41.04±4.01)%,P<0.01]。然而,在H2S后处理同时加入PI3K/Akt信号通路特异性抑制剂LY294002后,与H2S组相比,LY+H2S组心肌细胞存活率降低明显(63.65±2.01)%,CK、LDH活性以及心肌细胞凋亡率升高显著[(307.80±21.68)U/L,(421.51±15.95)U/L,(15.17±1.56)%,P<0.01];HIF-1α和p-Akt蛋白表达水平亦降低明显[(51.79±4.27)%,(47.42±3.15)%,P<0.05和P<0.01]。结论 H2S后处理可通过PI3K/Akt信号通路促进HIF-1α表达,从而拮抗心肌细胞的缺氧复氧损伤。ObjectiveTo study the protective effect of hydrogen sulfide（H2S） post-conditioning on hypoxia-reoxygenation injury in primary cultured cardiomyocytes from neonatal rats and its possible mechanism.Methods Sodium hydrosulfide（NaHS） was used as an exogenous donor of H2S.Primary cultured cardiomyocytes from neonatal rats were randomly divided into control group,hypoxia-reoxygenation（HR） group,dimethyl sulfoxide（DMSO） group,H2S post-conditioning group,and LY294002＋H2S post-conditioning group.Survival rate of cardiomyocytes and activity of creatine kinase（CK） and lactate dehydrogenase（LDH） in cultured cardiomyocytes were assayed before hypoxia and 2 h after hypoxia-reoxygenation,respectively.Apoptosis in the cardiomyocytes was detected by flow cytometry and expression of hypoxia-inducible factor-1alpha（HIF-1α）,p-Akt and Akt protein was detected by Western blotting.Results In 2 h after reoxygenation,the survival rate of cardiomyocytes was significantly higher in H2S post-conditioning group than in HR group [（71.55±1.46）% vs（62.03±1.29）%,P0.01],but the activity of CK and LDH and the apoptosis in the cardiomyocytes were significantly lower in H2S post-conditioning group than in HR group[（244.99±21.38）U/L vs（329.53±26.14）U/L,（371.64±18.62）U/L vs（427.69±13.25）U/L,（10.37±1.51）% vs（17.38±2.04）%,P0.01],and the expression level of HIF-1αand p-Akt was significantly higher in H2S post-conditioning group than in HR group [（63.93±4.64）% vs（41.82±6.14）%,（62.59±2.11）% vs（41.04±4.01）%,P0.01].However,after PI3K/Akt pathway inhibitor LY294002 was added during H2S post-conditioning,when compared with H2S post-conditioning group,the survival rate of cardiomyocytes was significantly lower（63.65±2.01） %,the activity of CK and LDH and the apoptosis of cardiomyocytes were significantly higher [（307.80±21.68）U/L,（421.51±15.95）U/L,（15.17±1.56）%,P0.01],and the expression level of HIF-1αand p-Akt protein was markedly lower[（51.79±4.

关 键 词：硫化氢 心肌缺血再灌注损伤 缺氧诱导因子-1Α 凋亡 PI3K/AKT 

分 类 号：R322.11[医药卫生—人体解剖和组织胚胎学] R329.26[医药卫生—基础医学]