Academy of Integrative Medicine, Fujian University of Traditional Chinese Medicine, Fuzhou, Fujian, 350122, China; Chen Keji Academic Thought Inheritance Studio, Fujian University of Traditional Chinese Medicine, Fuzhou, Fujian, 350122, China; Fujian Key Laboratory of Integrative Medicine on Geriatrics, Fujian University of Traditional Chinese Medicine, Fuzhou, Fujian, 350122, China.
Academy of Integrative Medicine, Fujian University of Traditional Chinese Medicine, Fuzhou, Fujian, 350122, China; Chen Keji Academic Thought Inheritance Studio, Fujian University of Traditional Chinese Medicine, Fuzhou, Fujian, 350122, China; Fujian Key Laboratory of Integrative Medicine on Geriatrics, Fujian University of Traditional Chinese Medicine, Fuzhou, Fujian, 350122, China; Department of Geriatrics, Xiyuan Hospital, China Academy of Chinese Medical Sciences, Beijing, 100091, China.
Biomed Pharmacother. 2021 May;137:111318. doi: 10.1016/j.biopha.2021.111318. Epub 2021 Feb 5.
Cardiac fibrosis plays an important role in hypertension-related contractile dysfunction and heart failure. Qingda granule (QDG), derived from the Qingxuan Jiangya decoction, has been used clinically for more than 60 years to treat hypertension. However, the effect of QDG on hypertensive cardiac fibrosis remains largely unknown. The objective of this study was to investigate the effect of QDG on cardiac fibrosis and explore the underlying mechanism in vivo and in vitro. For in vivo experiments, 30 male spontaneously hypertensive rats were randomly divided into groups that received no QDG or one of three doses (0.45, 0.9 or 1.8 g/kg/day). Positive-control animals received valsartan (VAL, 7.2 mg/kg/day). Treatments were administered by gavage for 10 weeks. All three doses of QDG and VAL led to significantly lower blood pressure than in SHR animals. Besides, all three doses of QDG and VAL attenuated pathological changes in SHR animals. However, only intermediate, high concentrations of QDG and VAL led to significantly lower left ventricle ejection fraction and left ventricle fractional shortening than in SHR animals. Therefore, the minimum and effective QDG dose (intermediate concentration of QDG) was selected for subsequent animal experiments in this study. Our results showed that intermediate concentration of QDG also significantly mitigated the increases in levels of α-smooth muscle actin (α-SMA), proliferating cell nuclear antigen (PCNA), collagen III, transforming growth factor-β1 (TGF-β1) and in the ratio of phospho-Smad2/3 to total Smad2/3 protein in cardiac tissue, based on immunohistochemistry, Western blotting, and Masson staining. For in vitro experiments, primary cardiac fibroblasts were stimulated with 100 nM angiotensin II in the presence or absence of QDG. And we tested different concentrations of QDG (3.125, 6.25, 12.5, 25, 50 μg/mL) in the cell viability experiment. Our results showed that 3.125, 6.25 and 12.5 μg/mL of QDG treatment for 24 h didn't affect the cell viability of cardiac fibroblasts. Consistently, QDG at 6.25 or 12.5 μg/mL significantly reduced cell viability and down-regulated α-SMA in primary cardiac fibroblasts were stimulated with 100 nM angiotensin II. Therefore, QDG at 12.5 μg/mL was chosen for the following cell experiment. Our results showed that QDG at 12.5 μg/mL alleviated the increase of PCNA, collagen Ⅲ, TGF-β1 expression, and the ratio of phospho-Smad2/3 to total Smad2/3 protein. Our studies in vitro and in vivo suggest that QDG reduces blood pressure and cardiac fibrosis as well as protecting cardiac function, and that it exerts these effects in part by suppressing TGF-β1/Smad2/3 signaling.
心脏纤维化在高血压相关的收缩功能障碍和心力衰竭中起着重要作用。 Qingda 颗粒（QDG）源自 Qingxuan Jiangya 汤，已在临床上使用超过 60 年用于治疗高血压。然而，QDG 对高血压性心脏纤维化的影响在很大程度上仍然未知。本研究的目的是研究 QDG 对心脏纤维化的影响，并在体内和体外探索其潜在机制。
在体内实验中，30 只雄性自发性高血压大鼠随机分为未接受 QDG 或三种剂量（0.45、0.9 或 1.8 g/kg/天）的组。阳性对照动物接受缬沙坦（VAL，7.2 mg/kg/天）。通过灌胃给药 10 周。所有三种剂量的 QDG 和 VAL 均导致 SHR 动物的血压明显降低。此外，所有三种剂量的 QDG 和 VAL 均减轻了 SHR 动物的病理变化。然而，只有中、高浓度的 QDG 和 VAL 导致 SHR 动物的左心室射血分数和左心室短轴缩短率明显降低。因此，本研究选择了 QDG 的最小有效剂量（中浓度 QDG）用于随后的动物实验。
我们的结果表明，中浓度 QDG 还显著减轻了心脏组织中α-平滑肌肌动蛋白（α-SMA）、增殖细胞核抗原（PCNA）、胶原 III、转化生长因子-β1（TGF-β1）和磷酸化 Smad2/3 与总 Smad2/3 蛋白比值的升高，基于免疫组织化学、Western blot 和 Masson 染色。
在体外实验中，原代心肌成纤维细胞在存在或不存在 QDG 的情况下用 100 nM 血管紧张素 II 刺激。并且我们在细胞活力实验中测试了不同浓度的 QDG（3.125、6.25、12.5、25、50 μg/mL）。我们的结果表明，3.125、6.25 和 12.5 μg/mL 的 QDG 处理 24 h 不会影响心肌成纤维细胞的细胞活力。一致地，6.25 或 12.5 μg/mL 的 QDG 显著降低了由 100 nM 血管紧张素 II 刺激的原代心肌成纤维细胞的细胞活力并下调了α-SMA。因此，选择 12.5 μg/mL 的 QDG 用于以下细胞实验。我们的结果表明，12.5 μg/mL 的 QDG 减轻了 PCNA、胶原 III、TGF-β1 表达的增加以及磷酸化 Smad2/3 与总 Smad2/3 蛋白的比值。
我们的体内和体外研究表明，QDG 降低血压和心脏纤维化并保护心脏功能，其部分通过抑制 TGF-β1/Smad2/3 信号通路发挥作用。
