丹参酮ⅡA调节microRNA-1保护缺氧心肌细胞的作用研究

目的:研究丹参酮Ⅱ A(TanshinoneⅡA)通过调节microRNA-1抗心肌细胞缺氧损伤的作用。方法:原代培养新生大鼠心肌细胞,建立心肌细胞缺氧模型。MTT法检测心肌细胞存活率(%);TUNEL、流式细胞术测心肌细胞凋亡率;激光共聚焦检测心肌细胞内钙离子Ca2+]i浓度的变化情况。结果:MTT结果显示丹参酮ⅡA对缺氧心肌细胞及过表达miR-1引起心肌细胞损伤具有保护作用。丹参酮ⅡA增加了缺氧心肌细胞的存活率(P0.05),同时给予丹参酮ⅡA和miR-1组与单独miR-1损伤组相比较,存活率也明显升高,呈现剂量依赖性。TUNEL结果显示丹参酮ⅡA可以抑制缺氧诱导的细胞凋亡,丹参酮ⅡA可以明显降低由缺氧导致的细胞凋亡率(P0.05)。共聚焦检测结果显示,缺氧损伤的心肌细胞内Ca2+]i显著升高1322.72±5.16(vs正常对照组,P0.05),丹参酮ⅡA则有效抑制由缺氧引起过高的Ca2+]i。miR-1诱导的细胞内Ca2+]i升高至1349.33±62.63,约为正常对照组的1.96倍,而丹参酮ⅡA则有效抑制胞内过高的Ca2+]i,从而发挥心肌保护作用。结论:丹参酮ⅡA可能是通过抑制胞内miR-1的表达,参与对钙离子浓度的调控,发挥其对心肌细胞的保护作用。

Tanshinone IIA Protect Hypoxic Myocardial Cells Through Regulating MicroRNA-1

Objective:To study and explore the mechanism of Tanshinone IIA (Tan) protecting hypoxic myocardial cells by regulating microRNA-1.Methods:Primary cultured neonatal cardiomyocytes and established the model of myocardial hypoxia. Cell viability was detected by MTT assay, apoptosis of myocardial cells and apoptosis percentage were detected by TUNEL assay and flow cytometry. Intracellular calciumconcentration (Ca2+]i) was measured by Laser Scanning Confocal.Results:MTT results showed that the Tan IIA could alleviate cell death induced by hypoxia, with the trend of dose-dependence, (P<0.05). TUNEL results also showed that Tan IIA could significantly reduce the percentage of hypoxia-induced apoptosis (P<0.05). The Ca2+]i increased significantly under hypoxia, while the Tan IIA could effectively inhibit the Ca2+]i and thus play a protective role (P<0.05).Conclusion:Tanshinone IIA can alleviate the hypoxia-induced apoptosis, possibly through regulating miRNA-1 and Ca2+]i, playing a protective effect on myocardial cells.