摘要目的:探讨丹参酮ⅡA通过介导TGF-β1发挥对心力衰竭大鼠心肌细胞自噬与凋亡的调控作用。方法:通过腹主动脉缩窄的方法建立大鼠的心力衰竭模型，术后腹腔注射丹参酮ⅡA，假手术组（Sham）为对照。超声心动图检测心脏结构与功能，HE染色与Masson染色观察心肌纤维形态与胶原容积分数。TUNEL染色与免疫印迹（Cleaved-Caspase-3、Bax、Bcl-2）分析细胞凋亡程度，自噬双标腺病毒mRTF-GFP-LC3荧光显微镜测定自噬水平与自噬流活性，免疫印迹检测自噬相关蛋白（Beclin 1、LC3-Ⅱ/LC3-Ⅰ）表达水平。ELISA检测心肌细胞培养上清中TGF-β1含量的变化。结果:建模成功后，丹参酮ⅡA显著降低心衰组升高的左室舒张末期内径[（7.45±0.67）mm比（9.72±0.28）mm]与收缩末期内径，升高心衰组降低的左室射血分数与短轴缩短率（ P<0.05）。Masson染色心肌组织胶原容积分数与TUNEL染色心肌细胞凋亡百分比，心衰组明显高于Sham组，丹参酮ⅡA组则是低于心衰组（ P<0.05）。与Sham组相比，心衰组Cleaved-Caspase-3、Bax表达上调，Bcl-2表达下调。与心衰组相比，丹参酮ⅡA组Cleaved-Caspase-3、Bax表达下调，Bcl-2表达上调（ P<0.05）。心肌细胞内荧光斑点总数、红色荧光斑点百分比、Beclin 1与LC3-Ⅱ/LC3-Ⅰ比值，以及心肌细胞培养上清中TGF-β1水平心衰组均高于Sham组，丹参酮ⅡA组低于心衰组（ P<0.05）。TGF-β1组比心衰组心肌细胞自噬与凋亡水平更高，SB431542预处理后，TGF-β1激活自噬与凋亡水平显著下降（ P<0.05）。 结论:TGF-β1可加重心衰心肌细胞激活的自噬与凋亡，丹参酮ⅡA可能通过降低心肌细胞TGF-β1分泌，抑制自噬与凋亡的过度激活，减轻心肌细胞损伤，逆转心肌重构，改善心功能。

abstractsObjective:To investigate the mediating effect of Tanshinone ⅡA (Tan ⅡA) on transforming growth factor-β1 (TGF-β1) and its regulation on cardiomyocytes autophagy and apoptosis in rats with heart failure (HF) .Methods:HF was modeled in rats by abdominal aorta coarctation, and Tan ⅡA was injected intraperitoneally after operation. A sham operation (Sham) group was included as the control group. The changes in cardiac structure and function were evaluated by echocardiography in vivo. The myocardial fiber morphology and collagen volume fraction (CVF) were determined by HE staining and Masson staining. The degree of cardiomyocytes apoptosis was analyzed by TUNEL staining and Western blotting (Cleaved-Caspase-3, Bax and Bcl-2). Fluorescence microscopy was used to determine the level of autophagy and the activity of autophagic flux by tandem mRFP-GFP-LC3 adenovirus reporting system. The autophagy-related proteins (Beclin 1 and LC3-Ⅱ/LC3-Ⅰ) levels were examined by Western blotting. The changes of TGF-β1 level in the culture supernatant of cardiomyocytes was determined by ELISA.Results:After successful modeling, Tan ⅡA significantly reduced the enlarged left ventricular end-systolic and end-diastolic dimensions[ (7.45±0.67) mm vs (9.72±0.28) mm], and increased the lowered left ventricular ejection fraction and fractional shortening in HF rats. The CVF (Masson stained) and cardiomyocytes apoptosis rate (TUNEL stained) in myocardial tissues in HF group were significantly higher than those in Sham group, while these values were lower in Tan ⅡA group than those in HF group (all P<0.05). Compared with the Sham group, the expressions of Cleaved-Caspase-3 and Bax were up-regulated, but the expression of Bcl-2 was down-regulated, in HF group. Compared with the HF group, the expressions of Cleaved-Caspase-3 and Bax were down-regulated, while the expression of Bcl-2 was up-regulated in Tan ⅡA group (all P<0.05). The total number of fluorescent spots, the percentage of red fluorescent spots, LC3-Ⅱ/LC3-Ⅰ ratio in cardiomyocytes, and the level of TGF-β1 in the culture supernatant of cardiomyocytes in the HF group were higher than those in the Sham group, while these values were lower in Tan ⅡA group than those in the HF group (all P<0.05). The levels of autophagy and apoptosis in cardiomyocytes in TGF-β1 group were higher than those in HF group. After SB431542 pretreatment, the levels of autophagy and apoptosis activated by TGF-β1 decreased significantly (all P<0.05) . Conclusion:In HF, TGF-β1 may aggravate the activation of cardiomyocytes autophagy and apoptosis. Tan ⅡA may reduce TGF-β1 produced by cardiomyocytes, inhibit excessive activation of autophagy and apoptosis, alleviate cardiomyocytes injury, reverse myocardial remodeling, and thereby improve cardiac function.