右美托咪定调控Nrf2/HO-1通路对H2O2诱导心肌细胞氧化应激损伤的作用研究

Effect of dexmedetomidine regulating Nrf2/HO-1 pathway on H2O2-induced oxidative stress injury in cardiomyocytes

摘要:

目的 探讨右美托咪定调控核因子E2相关因子2（Nrf2）/血红素加氧酶1（HO-1）通路对过氧化氢（H₂O₂）诱导心肌细胞氧化应激损伤的作用。方法 体外培养大鼠H9C2心肌细胞，设置对照组、H₂O₂组、1 μmol右美托咪定+H₂O₂组、5 μmol右美托咪定+H₂O₂组、10 μmol右美托咪定+H₂O₂组。CCK-8法检测各组H9C2细胞增殖情况；酶联免疫吸附试验（ELISA）检测各组H9C2细胞丙二醛（MDA）、超氧化物歧化酶（SOD）水平；实时荧光定量聚合酶链反应（qRT-PCR）检测各组H9C2细胞Nrf2、HO-1 mRNA相对表达量；Western blotting检测各组H9C2细胞Nrf2、HO-1蛋白相对表达量。结果 与对照组比较，H₂O₂组H9C2细胞存活率、SOD水平、Nrf2、HO-1 mRNA及蛋白相对表达量降低，MDA水平升高（P <0.05）；与H₂O₂组比较，1 μmol右美托咪定+H₂O₂组、5 μmol右美托咪定+H₂O₂组、10 μmol右美托咪定+H₂O₂组H9C2细胞存活率、SOD水平、Nrf2、HO-1 mRNA及蛋白相对表达量均升高，MDA水平降低（P <0.05），且呈右美托咪定浓度依赖性。结论 右美托咪定可能通过激活Nrf2/HO-1通路，发挥对H₂O₂诱导心肌细胞氧化应激损伤的保护作用。

Abstract:

Objective To investigate the effect of dexmedetomidine on hydrogen peroxide (H₂O₂)-induced oxidative stress injury of cardiomyocytes by regulating the nuclear factor erythroid 2 related factor 2 (Nrf2)/heme oxygenase-1 (HO-1) pathway.Methods Rat H9C2 cardiomyocytes were cultured in vitro, and the control group, H₂O₂ group, 1 μmol dexmedetomidine + H₂O₂ group, 5 μmol dexmedetomidine + H₂O₂ group, 10 μmol dexmedetomidine + H₂O₂ group were set up. The proliferation of H9C2 cells was detected by CCK-8 method; the levels of malondialdehyde (MDA) and superoxide dismutase (SOD) in H9C2 cell culture medium were detected by enzyme-linked immunosorbent assay (ELISA); the expressions of Nrf2, HO-1 mRNAs in H9C2 cells were detected by real-time fluorescent quantitative PCR (qRT-PCR); and the expressions of Nrf2, HO-1 proteins in H9C2 cells were detected by Western blotting.Results Compared with the control group, the H9C2 cell survival rate, SOD level, Nrf2 mRNA, HO-1 mRNA, HO-1 protein expression levels in H₂O group were decreased, and MDA level were increased (P < 0.05); compared with H₂O group, the H9C2 cell survival rate, SOD level, Nrf2, HO-1 mRNA and protein expression levels in 1, 5, 10 μmol dexmedetomidine + H₂O₂ groups were increased, and MDA level were decreased (P < 0.05); and dexmedetomidine was concentration-dependent.Conclusion Dexmedetomidine can protect cardiomyocytes from H₂O₂ - induced oxidative stress injury by activating Nrf2/HO-1 pathway.