Department of Traditional Chinese Medicine, School of Traditional Chinese Medicine, Nanfang Hospital (ZengCheng Branch), Southern Medical University, Guangzhou 510515, China.
Department of Traditional Chinese Medicine (Institute of Integration of Traditional and Western Medicine of Guangzhou Medical University, State Key Laboratory of Respiratory Disease), the Second Affiliated Hospital of Guangzhou Medical University, Guangzhou Medical University, Guangzhou 510260, China.
Phytomedicine. 2022 Sep;104:154277. doi: 10.1016/j.phymed.2022.154277. Epub 2022 Jun 15.
Excessive myocardial fibrosis is the pathological basis of heart failure following myocardial infarction (MI). Although calycosin improves cardiac function, its effect on cardiac fibrosis and cardiac function after MI in mice and its precise mechanism remain unclear.
Here, we firstly investigated the effects of calycosin on cardiac fibrosis and ventricular function in mice after MI and the role of transforming growth factor-beta receptor 1 (TGFBR1) signaling in the amelioration of cardiac fibrosis and ventricular function.
In vivo effects of calycosin on cardiac structure and function in mice with MI induced by left anterior descending coronary artery ligation were determined by hematoxylin and eosin staining, Masson trichrome staining, and echocardiography. The molecular mechanism of the interaction between TGFBR1 and calycosin was investigated using molecular docking, molecular dynamics (MD) simulation, surface plasmon resonance imaging (SPRi), immunohistochemistry, and western blotting (WB). Subsequently, cardiac-specific Tgfbr1 knockout mice were used to verify the effects of calycosin. The effect of calycosin on primary cardiac fibroblasts (CFs) proliferation and collagen deposition was detected using cell counting (CCK-8), EdU assay, and WB in vitro. CFs infected with an adenovirus that encodes TGFBR1 were used to verify the effects of calycosin.
In vivo, calycosin attenuated myocardial fibrosis and cardiac dysfunction following MI in a dose-dependent pattern. Calycosin-TGFBR1 complex was found to have a binding energy of -9.04 kcal/mol based on molecular docking. In addition, calycosin bound steadily in the cavity of TGFBR1 during the MD simulation. Based on SPRi results, the solution equilibrium dissociation constant for calycosin and TGFBR1 was 5.11 × 10 M. Calycosin inhibited the expression of TGFBR1, Smad2/3, collagen I, and collagen III. The deletion of TGFBR1 partially counteracted these effects. In vitro, calycosin suppressed CFs proliferation and collagen deposition after TGF-β1 stimulation by suppressing the TGFBR1 signaling pathway. The suppressive effects of calycosin were partially rescued by overexpression of TGFBR1.
Calycosin attenuates myocardial fibrosis and cardiac dysfunction following MI in mice in vivo via suppressing the TGFBR1 signaling pathway. Calycosin suppresses CFs proliferation and collagen deposition induced by TGF-β1 via inhibition of the TGFBR1 signaling pathway in vitro.
心肌纤维化过度是心肌梗死后心力衰竭的病理基础。尽管毛蕊异黄酮能改善心功能，但它对心肌梗死后小鼠心肌纤维化和心功能的影响及其确切机制尚不清楚。
本研究首次探讨了毛蕊异黄酮对小鼠心肌梗死后心肌纤维化和心室功能的影响，以及转化生长因子-β受体 1（TGFBR1）信号在改善心肌纤维化和心室功能中的作用。
通过苏木精-伊红染色、Masson 三色染色和超声心动图检测左前降支结扎诱导的心肌梗死后小鼠心肌结构和功能的体内作用。采用分子对接、分子动力学（MD）模拟、表面等离子体共振成像（SPRi）、免疫组织化学和蛋白质印迹（WB）技术研究 TGFBR1 与毛蕊异黄酮相互作用的分子机制。随后，使用心脏特异性 Tgfbr1 基因敲除小鼠验证毛蕊异黄酮的作用。体外采用细胞计数（CCK-8）、EdU 检测和 WB 检测毛蕊异黄酮对原代心肌成纤维细胞（CFs）增殖和胶原沉积的影响。用携带 TGFBR1 基因的腺病毒感染 CFs，验证毛蕊异黄酮的作用。
体内，毛蕊异黄酮呈剂量依赖性减轻心肌梗死后心肌纤维化和心功能障碍。分子对接显示毛蕊异黄酮-TGFBR1 复合物的结合能为-9.04kcal/mol。此外，MD 模拟表明毛蕊异黄酮在 TGFBR1 腔中稳定结合。基于 SPRi 结果，毛蕊异黄酮与 TGFBR1 的溶液平衡解离常数为 5.11×10-6M。毛蕊异黄酮抑制 TGFBR1、Smad2/3、胶原 I 和胶原 III 的表达。TGFBR1 缺失部分拮抗了这些作用。体外，毛蕊异黄酮通过抑制 TGFBR1 信号通路抑制 TGF-β1 刺激后的 CFs 增殖和胶原沉积。过表达 TGFBR1 部分挽救了毛蕊异黄酮的抑制作用。
毛蕊异黄酮通过抑制 TGFBR1 信号通路减轻体内小鼠心肌梗死后的心肌纤维化和心功能障碍。毛蕊异黄酮通过抑制 TGFBR1 信号通路抑制 TGF-β1 诱导的 CFs 增殖和胶原沉积。
