摘要目的:探讨鸭跖草调控NADPH氧化酶4(Nox4)对缺氧/复氧(H/R)心肌细胞凋亡及炎性因子表达的影响。方法:利用H/R诱导H9c2细胞损伤，用不同浓度鸭跖草提取物处理细胞，噻唑蓝(MTT)法检测细胞活性，流式细胞术检测细胞凋亡，试剂盒检测超氧化物歧化酶(SOD)、丙二醛(MDA)、乳酸脱氢酶(LDH)水平，酶联免疫吸附试验(ELISA)检测TNF-α、IL-1β、IL-6水平，蛋白质印迹法(Western blot)检测Bcl-2相关X蛋白(Bax)、含半胱氨酸的天冬氨酸蛋白水解酶3(Caspase-3)、Nox4蛋白表达，实时荧光定量PCR(qPCR)检测Nox4 mRNA表达。用si-Nox4转染H9c2细胞，并经H/R处理，观察抑制Nox4对H/R心肌细胞H9c2的细胞活性、凋亡，以及SOD、MDA、LDH和炎性因子的影响。用pcDNA3.1-Nox4转染H9c2细胞，并用鸭跖草提取物和H/R处理，评价其对H9c2细胞活性、凋亡，以及SOD、MDA、LDH和炎性因子的影响。结果:H/R处理后，H9c2细胞的存活率和SOD活性显著降低，细胞凋亡率以及Caspase-3、Bax蛋白、MDA、LDH、TNF-α、IL-1β、IL-6、Nox4 mRNA、Nox4蛋白表达量明显增加( P<0.05)。10 μg/ml和20 μg/ml鸭跖草提取物显著提高H/R处理后H9c2细胞的细胞存活率、SOD活性，明显降低凋亡率和Caspase-3、Bax蛋白、MDA、LDH、TNF-α、IL-1β、IL-6、Nox4 mRNA、Nox4蛋白表达量( P<0.05)，与抑制Nox4表达的作用结果一样。过表达Nox4能逆转鸭跖草提取物对H/R诱导的心肌细胞活性、SOD活性的促进作用，和对细胞凋亡以及对Caspase-3、Bax蛋白、MDA、LDH、TNF-α、IL-1β、IL-6表达的抑制作用。 结论:鸭跖草通过调控Nox4表达保护H/R诱导的心肌细胞损伤，提高细胞活性，并抑制细胞凋亡及炎性因子表达。

abstractsObjective:To investigate the effects of Commelina communis L. on hypoxia/reoxygenation (H/R)-induced apoptosis of myocardial cells and expression of inflammatory factors through regulating NADPH oxidase 4 (Nox4). Methods:H9c2 cells were subjected to H/R to establish the injury model. These cells were then treated with different concentrations of Commelina communis L. extract. Cell activity and apoptosis were measured by MTT method and flow cytometry, respectively. Superoxide dismutase (SOD), malondialdehyde (MDA) and lactate dehydrofenase (LDH) levels were detected. ELISA was performed to detect TNF-α, IL-1β and IL-6 levels. Western blot was used to detect the expression of Bcl-2-associated X protein (Bax), cysteine-containing aspartic protease 3 (Caspase-3) and Nox4. Real-time quantitative PCR (qPCR) was used to measure the expression of Nox4 at mRNA level. H9c2 cells were transfected with si-Nox4 and subjected to H/R. Changes in the activity and apoptosis of H9c2 cells, and the expression of SOD, MDA, LDH and inflammatory factors were observed after inhibiting Nox4 expression. H9c2 cells transfected with pcDNA3.1-Nox4 were treated with Commelina communis L. extract and subjected to H/R to evaluate the effects on the cell activity and apoptosis, as well as the expression of SOD, MDA, LDH and inflammatory factors. Results:The survival rate and SOD activity of H9c2 cells exposed to H/R were significantly reduced, but the apoptosis rate, the levels of Caspase-3, Bax protein, MDA, LDH TNF-α, IL-1β and IL-6, and the expression of Nox4 at both mRNA and protein levels were dramatically increased ( P<0.05). As with inhibition of Nox4 expression, Commelina communis L. extract at the concentrations of 10 μg/ml and 20 μg/ml could obviously increase the survival rate and SOD activity of H9c2 cells after H/R exposure, and reduce the apoptosis rate and the expression of Caspase-3, Bax protein, MDA, LDH TNF-α, IL-1β and IL-6, as well as Nox4 expression at mRNA and protein levels ( P<0.05). Overexpression of Nox4 reversed the effects of Commelina communis L. extract on promoting cardiomyocyte cell activity and SOD activity, inhibiting cell apoptosis, and downregulating the expression of Caspase-3, Bax protein, MDA, LDH, TNF-α, IL-1β and IL-6 in the H/R injury model. Conclusions:Commelina communis L. could protect against H/R-induced myocardial cell injury, improve cell activity, and inhibit cell apoptosis and the expression of inflammatory factors through regulating Nox4 expression.