α-硫辛酸对H9 c2心肌细胞低氧及低氧/复氧损伤的保护作用及其机制探讨

目的：探讨α-硫辛酸(α-LA)对H9c2心肌细胞低氧及低氧/复氧损伤的保护作用及其作用机制。方法研究包括H9 c2心肌细胞低氧实验和低氧/复氧实验两部分,分成常氧组、低氧组或低氧/复氧组、LA组、乙醛脱氢酶抑制剂异黄酮苷(Daidzin)组(Daidzin组)、二甲亚砜(DMSO)溶剂对照组( DMSO组)。采用噻唑蓝( MTT)比色法检测心肌细胞存活率；微量酶标法测定乳酸脱氢酶( LDH)活性；ELISA法检测心肌细胞乙醛脱氢酶2(ALDH2)活性；硫代苯巴比妥酸法检测丙二醛( MDA)水平。结果与常氧组比较,低氧组及低氧/复氧组细胞存活率均下降(P<0．01),LDH活性及MDA含量均升高(P<0．01)；与低氧组或低氧/复氧组比较, LA组细胞存活率上升( P <0．01)、ALDH2活性增加( P <0．05)、LDH活性及MDA含量降低(P<0．01)；LA组、Daid-zin组、DMSO组3组比较, LA组与DMSO组间存活率、AL-DH2、LDH、MDA比较差异均无统计学意义( P>0．05)；Daid-zin组与LA组、DMSO组比较,细胞存活率及ALDH2活性降低(P<0．05),LDH活性及MDA含量升高(P<0．05),差异均有统计学意义( P<0．05)。结论α-LA可通过上调AL-DH2活性并减少过氧化终产物形成,最终减轻心肌细胞低氧及低氧/复氧过程中的氧化损伤。

The protective effects of alpha-lipoic on H9 c2 cardiomyocytes undergoing hypoxia or hypoxia/reoxygenation(H/R) injury and its possible mechanism

Objective To investigate the protective effects of alpha-lipoic (α-LA) on H9c2 cardiomyocytes under-going hypoxia or hypoxia/reoxygenation(H/R) injury and explore its possible mechanisms. Methods H9c2 car-diomyocytes in hypoxia or H/R injury researches were respectively divided into normal control group, hypoxia or H/R group, hypoxia or H/R + α-LA group (LA group), hypoxia or H/R+α-LA + Daidzin group (Daidzin group) and hypoxia or H/R+α-LA +DMSO group ( DMSO group) . The myocardial cell survival was detected by MTT,the activity of LDH and ALDH2 were respectively analyzed by microtitration and ELISA,the MDA level was measured by TBA. Results Compared to the normal control group, the cell survival rates of hypoxia and H/R group were decreased ( P<0. 01 ) , the levels of MDA and LDH were significantly increased ( P<0. 01 ) . Compared to the hypoxia or H/R group, the cell survival rates and ALDH2 activities of LA group were improved (P<0. 05), the levels of MDA and LDH were decreased (P<0. 01). Compared to the LA group and DMSO group, the cell survival rates and ALDH2 activities of Daidzin group were decreased ( P<0. 05 ) , the levels of MDA and LDH were increased ( P<0. 05 ) , and no significant differences of all the above measures were found between LA group and DMSO group ( P>0. 05 ) . Conclusion α-LA can protect H9 c2 cardiomyocytes from hypoxia or H/R injury by means of upregulating activities of ALDH2 and decreasing hypoxia or H/R induced lipid peroxidation.