辛伐他汀对过氧化氢损伤的心肌细胞的保护作用

Protective Effects of Simvastatin against Hydrogen Peroxide Induced Myocardial Injury in Cultured Rat Neonatal Cardiomyocytes

目的观察辛伐他汀对过氧化氢(H2O2)损伤的心肌细胞的保护作用,阐明此作用与其诱导心肌抗氧化酶活性、减少氧活性物质的生成间的关系。方法用培养的新生SD大鼠心肌细胞做实验。用H2O2建立细胞损伤模型,细胞培养前用不同浓度辛伐他汀和甲羟戊酸进行预处理。测定心肌细胞活力、乳酸脱氢酶(LDH)浓度及丙二醛(MDA)水平,用荧光探针DCF-DA测定细胞内活性氧(ROS)水平,反映心肌损伤及氧活性物质的生成情况。测定心肌细胞内超氧化物歧化酶(SOD)活性,反映抗氧化酶活性。结果辛伐他汀预可剂量依赖性地提高H2O2损伤心肌细胞的细胞活力(P<0.01),并减少损伤时LDH的漏出(P<0.01),MDA的生成量也明显减少(P<0.01),心肌ROS明显下降;而心肌细胞SOD活性较H2O2损伤组增高(P<0.01)。甲羟戊酸(100μmol.L-1)能完全阻断辛伐他汀预处理的保护作用。结论辛伐他汀可能通过MVA通路,使SOD等有抗氧化作用的酶合成增加,对H2O2引起的心肌细胞损伤起心肌保护作用。

Objective To observe the protective effect of simvastatin on hydrogen peroxide（ H2O2 ） induced myocardial injury and to illustrate the relationship between this effect and its action to promote the activity of myocardial antioxidase so as to decrease the formation of oxygen active substances. Methods Cultured rat ventricular myocytes were divided into different groups. The cell injury model was establish by H2O2 , and before cell culture different concentrations of simvastatin and mevalonic acid（MVA） were used for pre-treatment. Cell viability （ CV）, lactate dehydrogenase （LDH） release, and malondialdehyde （MDA） formation were measured. Superoxide dimutase （SOD） activity was measured to reflect the activity of antioxidase. The fluoresent probe DCF-DA was used to detect intracellular levels of reactive oxygen species（ROS） to reflect myocardial injury and the formation of O2 active substances. Results Simvastatin could dose-dependently increase CV and decrease LDH release as compared with H2O2 injury （HC） group （ H2O2 200 μmol·L^-1） （ P 〈 0.01 ）. Simvastatin pretreatment could significantly increase SOD activity （P 〈 0.01 ）, and reduce intracellar ROS （ P 〈 0.01 ） and MDA formation （ P 〈 0.01 ） as compared with HC group （ H2O2 200μmol·L^-1） . Mevalonic acid （ MVA ） （ 100 μmol·L^-1） could block the protection of simvastatin completely. Conclusion Simvastatin has protective effects on H2O2 induced myocardial injury probably through MVA pathway to increase the activity of antioxidases as SOD.