线粒体ATP敏感性钾离子通道开放剂改善冠心病大鼠模型心肌氧化应激损伤的分子机制

Molecular mechanism of mitochondrial mitoKATP channel openers in improving the cardiac oxidative stress/injury in rat models of coronary heart disease

摘要:

目的 探索线粒体ATP敏感性钾离子通道(mitoKATP)开放剂改善冠心病大鼠模型心肌氧化应激损伤的分子机制。方法 选取40只SD大鼠随机分为4组:正常对照组(不造模且不给予二氮嗪药物干预)、假手术组(仅切皮不进行造模手术)、模型组(制作冠心病大鼠模型,但不给予二氮嗪药物干预)和药物组(制作冠心病大鼠模型,给予二氮嗪药物3 mg/kg干预),每组10只。利用实时荧光定量聚合酶链式反应及Western blotting实验测定各组血管生成因子[成纤维细胞生长因子2(FGF-2)和血管内皮生长因子(VEGF)]mRNA及相关蛋白的表达量,同时比较各组大鼠细胞内的乳酸脱氢酶、线粒体膜电位(MMP)和细胞死亡率。采用SPSS 22.0软件进行数据处理。组间比较采用方差分析或者t检验。结果 与模型组相比,药物组大鼠FGF-2[(100.21±12.33)×10³ vs (120.43±10.33)×10³ IU]与VEGF [(163.31±9.33)×10³ vs (181.33±11.13)×10³ IU]mRNA转录水平、FGF-2 [(0.69±0.33) vs (1.32±0.33)与VEGF [(0.68±0.33) vs (1.20±0.13)]表达水平、乳酸脱氢酶[(49.32±3.51) vs (156.12±10.18)U/L]表达均显著降低(P＜0.05)。与模型组相比,药物组细胞死亡率显著降低[(30.32±3.48)% vs(66.12±3.23)%],而荧光强度显著增加[(780.12±9.20) vs(220.24±6.15),P＜0.05]。结论 mitoKATP通道开放剂可通过促进冠心病大鼠血管FGF-2和VEGF增加,增强乳酸脱氢酶活性,降低MMP、细胞死亡率和冠心病大鼠心肌氧化应激损伤。

Abstract:

Objective To investigate the molecular mechanism of mitochondrial mitochondrial ATP-sensitive potassium channels (mitoKATP) opener in improving myocardial oxidative stress/injury in rates with coronary heart disease (CHD). Methods A total of 40 SD rats were randomly divided into 4 groups with 10 in each:control group (without modeling and intervention of diazoxide drug), sham operation group (with skin cutting but without modeling), and model group (modeling of coronary heart disease but without intervention of diazoxide) and drug group (with modeling of coronary heart disease and intervention of diazoxide at 3 mg/kg). mRNA expression of angiogenic factors[fibroblast growth factor 2 (FGF-2) and vascular endothelial growth factor (VEGF)] and related proteins for each group were measured using real-time fluorescence quantitative polymerase chain reaction and Western blotting. The groups were compared in lactate dehydrogenase, mitochondrial membrane potential (MMP) and cell death rate. SPSS statistics 22.0 was used of data processing, and analysis of variance (ANOVA) or t test for comparison between groups. Results Compared with the model group, drug group had significantly lower mRNA transcription of FGF-2 [(100.21±12.33)×10³ vs (120.43±10.33)×10³ IU] and VEGF [(163.31±9.33)×10³ vs (181.33±11.13)×10³ IU] and expression of FGF-2 [(0.69±0.33) vs (1.32±0.33)], VEGF [(0.68±0.33) vs (1.20±0.13)], and lactate dehydrogenase [(49.32±3.51) vs (156.12±10.18)U/L]. Compared with the model group, the cell death rate in the drug group decreased [(30.32±3.48)% vs (66.12±3.23)%], but the fluorescence intensity increased [(780.12±9.20) vs (220.24 ±6.15)] (P<0.05). Conclusion mitoKATP channel opener can decrease MMP, cell death rate and myocardial oxidative stress/injury in rats with coronary heart disease by increasing vascular FGF-2 and VEGF and enhancing activity of lactate dehydrogenase.