柚皮苷对H_2O_2诱导H9c2心肌细胞损伤保护作用

Protective effect of naringin on H9c2 myocardial cell injury induced by H_2O_2

目的探讨柚皮苷对H_2O_2诱导的H9c2心肌细胞凋亡的保护作用及机制。方法体外培养H9c2心肌细胞,用H_2O_2诱导建立细胞凋亡模型。实验设对照组、模型组、柚皮苷低、中、高剂量组(10、20、40μmol/L),噻唑蓝法检测细胞活力并用显微镜观察各组细胞形态;原位末端标记法检测H9c2心肌细胞凋亡情况;RT-PCR及Western blot法检测凋亡相关因子Bcl-2、Bax、caspase-3 m RNA及蛋白表达。结果与对照组比较,模型组细胞凋亡率[(17.2±2.1)%]明显升高(P<0.01);与模型组比较,10、20、40μmol/L柚皮苷组细胞凋亡率[分别为(10.7±1.9)%、(5.7±1.2)%、(6.4±1.5)%]均下降(均P<0.05)。与对照组比较,模型组H9c2心肌细胞Bcl-2蛋白表达水平(0.76±0.16)明显下调,Bax、caspase-3蛋白表达水平[分别为(5.42±0.52)、(1.09±0.11)]均上调(均P<0.01);与模型组比较,10、20、40μmol/L柚皮苷组H9c2心肌细胞Bcl-2蛋白表达水平[分别为(1.37±0.11)、(1.65±0.09)、(1.65±0.15)]均上调,Bax、caspase-3蛋白表达水平[分别为(2.78±0.55)、(3.43±0.15)、(2.69±0.26)和(0.59±0.08)、(0.77±0.06)、(0.82±0.05)]均下调(均P<0.05)。结论柚皮苷对H_2O_2诱导的H9c2心肌细胞损伤具有一定保护作用,其机制可能与其对凋亡信号途径的抑制作用有关。

Objective To examine the protective effect and mechanism of naringin on H2O2-induced apoptosis of H9c2 myocardial cells. Methods H9c2 myocardial cells were cultured in vitro and a H9c2 myocardial cell apoptosis model was induced with hydrogen peroxide （H2O2）. Five H9c2 myocardial cell groups were established： a control, model, low-, moderate-, and high-dose （10, 20, and 40 μmol/L） naringin pretreatment group. Cell viability was detected with 3- （4, 5- dimethyl-2-thiazolyl） -2, 5-diphenyl-2-H-tetrazolium bromide （MTT） assay and cell morphology was observed with microscope. The apoptosis of H9c2 myocardial ceils was detected with terminal-deoxynucleotidyl transferase mediated nick end labeling （TUNEL） method. The expressions of B cell lymphoma 2 （Bel-2）, BCL2-associated X protein （Bax）, caspase-3 mRNA and protein were detected with real-time reverse transcription PCR （RT-PCR） and Western blot. Results Compared with that of the control group, the apoptotic rate （17.2 ± 2. %） of the model group was significantly higher （P 〈 0.01）; compared with that the model group, the apoptotic rate of low-, moderate-, and high-dose naringin pretreatment group were significantly decreased （10.7 ± 1.9%, 5.7 ± 1.2%, and 6.4 ± 1.5%） （all P 〈 0.05）. The Bcl-2 protein expression （0.76 ± 0.16） in H9c2 cardiomyocytes of the model group was significantly lower and the protein expressions of Bax and caspase-3 were significantly increased compared to those of the control group （all P 〈 0.01）. The protein expressions of Bcl-2 （1.37 ± 0.1 1, 1.65 ± 0.09, andl.65 ± 0.15） in H9c2 myocardial cells of low-, moderate-, and high-dose naringin pretreatment group were significantly increased; while those of Bax （2.78 ± 0.55, 3.43 ± 0.15, and 2.69 ± 0.26） and easpase-3 （0.59 ± 0.08, 0.77 ± 0.06, and 0.82 ± 0.05） were significantly decreased compared to those of the control group （all P 〈 0.05）. Conclusion Naringin could inhibit apoptosis of H9c2 myocardial cells induced by H2O2, which may be related to its inhibitory effect on the apoptotic signaling pathway.