当归红芪超滤物对氧化损伤乳鼠心肌细胞的保护作用及其机制

目的 探讨当归红芪超滤物对H_2O_2致乳鼠心肌细胞氧化损伤的保护作用及其可能机制.方法 用高浓度的H_2O_2(400 μmol/L)在Wistar乳鼠原代培养的心肌细胞上建立氧化损伤模型,用不同质量浓度的当归红芪超滤物(3.75、7.5、15 mg/mL)进行干预.在倒置显微镜下观察各实验组心肌细胞的搏动频率,用MTT法检测心肌细胞的存活率,用试剂盒检测细胞培养上清液中乳酸脱氢酶(LDH)、肌酸激酶(CK)的活性及细胞内超氧化物歧化酶(SOD)的活性、丙二醛(MDA)、髓过氧化物酶(MPO)的量.RT-PCR技术检测caspase-3、hsp70基因在心肌细胞中的表达情况.结果 当归红芪超滤物显著提高氧化损伤心肌细胞的细胞活力;与损伤组比较,当归红芪超滤物各干预组心肌细胞LDH、CK、MPO、MDA量显著降低(P<0.01),SOD活性显著提高(P<0.01),caspase-3基因表达显著降低(P<0.05),hsp70基因表达显著提高(P<0.05),差异具有统计学意义;并且当归红芪超滤物的抗氧化损伤作用呈剂量依赖性.结论 当归红芪超滤物具有良好的抗氧化损伤作用,其机制可能与清除自由基、上调hsp70表达、抑制caspase-3活性有关.

Protection of ultra-filtration extract mixture from Angelica sinensis and Hedysarum polybotrys on oxidative damage in cardiomyocytes of neonatal rats and its mechanism

Objective To investigate whether the administration of the ultra-filtration extract mixture from Angelica sinensis and Hedysarum polybotrys is able to protect cardiomyocytes from oxidative injury of rats induced by H_2O_2 and its potential mechanism. Methods Myocardial cells from 2-3 d neonatal rats were cultured in DF medium and the cellular injury was induced by H_2O_2. The ultra-filtration extract mixture from A. sinensis and H. polybotrys was given in three doses of 3. 75, 7. 5, and 15 mg/mL. Morphological changes of cardiomyocytes were observed by microscope. Survival rate of myocardial cells was assessed using MTT. The cardiomyocyte damages were estimated by detecting lactate dehydrogenase (LDH) and creatine kinase (CK) releases in the medium, superoxide dismutase (SOD) activities and intracellular malondialdehyde (MDA), and myeloperoxidase (MPO) contents. The levels of caspase-3 and hsp70 expression in cardiomyocytes were measured by RT-PCR. Results The ultra-filtration extract mixture could protect the cardiomyocytes from H_2O_2 injury in a dose-dependent manner (3. 75, 7. 5, and 15 mg/mL). The ultra-filtration extract mixture could significantly decrease LDH and CK leakages and intracellular MDA and MPO contents, increase SOD activity, upregulate hsp70 expression, and downregulate caspase-3 expression. Conclusion The ultra-filtration extract mixture has protection on cardiomyocytes injured by H_2O_2 through improving cell antioxidant ability, upregulating hsp70 expression, and inhibiting caspase-3 activity.