PS-B12-9: ASTRAGALOSIDE IV INHIBITS HYDROGEN PEROXIDE-INDUCED APOPTOSIS IN H9C2 CELLS BY ATTENUATING OXIDATIVE STRESS AND MITOCHONDRIAL DAMAGE

Abstract

Backgrounds: Oxidative stress and mitochondrial damage play an important role in the pathology of cardiomyocytes apoptosis. However, the effects of Astragaloside IV(As-IV) on mitochondrial function have not been uncertain. Therefore, we assumed that As-IV inhibits hydrogen peroxide-induced apoptosis in H9c2 cells by attenuating oxidative stress and mitochondrial damage. Objectives: To investigate the effects and mechanisms of As-IV on hydrogen peroxide-induced apoptosis in H9c2 cells. Methods: H9c2 cells were divided into three groups, including normal control group (cultured without intervention), hydrogen peroxidegroup (cultured with 200 μmol/L hydrogen peroxide for 2 hours), As-IV group (cultured with 100 μmol/L As-IV for 1 hour), As-IV with hydrogen peroxide group (pretreated with 100 μmol/L As-IV for 1 hour, then incubated with hydrogen peroxide for 2 hours). FITC/PI and DCFH-DA are stained to examine levels of apoptosis and ROS receptively. Levels of SOD and MDA were measured. Stained with JC-1 probe to observe the change of mitochondrial membrane potential (MMP). Western-blot was detected to analyze the expression of Drp-1. Results 1: The apoptosis rate of hydrogen peroxide group ((13.22 ± 3.17 vs 40.55 ± 13.74)%, P < 0.05) was significantly higher than that of control group, which was lower in As-IV with hydrogen peroxide group((23.43 ± 4.3 vs 40.55 ± 13.74) %, P < 0.05). 2. The ROS levels were higher in hydrogen peroxide group than control group((73.53 ± 5.33 vs 39.02 ± 7.90) %, P < 0.05), which were significant reduced in As-IV with hydrogen peroxide group((57.6 ± 4.63 vs 73.53 ± 5.33) %, P < 0.05) Meanwhile, the activity of MDA was increased and the activity of SOD was decreased in hydrogen peroxide group compared with that in control group((10.97 ± 0.56 vs 4.85 ± 0.55) nmol/mL, P < 0.05), ((1192.23 ± 341.59 vs 2710.95 ± 274.32)U/L, P < 0.05). Compared with hydrogen peroxide group, As-IV with hydrogen peroxide group significantly decrease the activity of MDA and increase the activity of SOD ((6.58 ± 0.79 vs 10.97 ± 0.56) nmol/mL, P < 0.05), ((1984.66 ± 188.81 vs 1192.23 ± 341.59) U/L, P < 0.05). 3. MMP was lower and the expression of Drp1 was higher in hydrogen peroxide group than that in control group ((0.31 ± 0.01 vs 1.52 ± 0.25) %, P < 0.05), ((0.86 ± 0.003 vs 0.45 ± 0.004) %, P < 0.05). Compared with hydrogen peroxide group, MMP was significantly increased and the expression of Drp1 was downregulated ((0.65 ± 0.38 vs 0.31 ± 0.01) %, P < 0.05), ((0.72 ± 0.005 vs 0.86 ± 0.003) %, P < 0.05). Conclusions: As-IV exerts protective effects on hydrogen peroxide-induced apoptosis by attenuating oxidative stress and mitochondrial damage.