目的 探讨注射用益气复脉（冻干）（Yiqi Fumai Lyophilized Injection，YQFM）通过上调心脏内皮机械敏感离子通道（piezo-type mechanosensitive ion channel component 1，Piezo1）激活一氧化氮（nitric oxide，NO）信号通路，从而抑制心肌肥大，改善压力超负荷所致心力衰竭（heart failure，HF）。方法 采用主动脉弓缩窄（transverse aortic constriction，TAC）手术制备小鼠HF模型，术后2周ip不同剂量YQFM（0.13、0.26、0.53 g/kg）和卡托普利（20 mg/kg）进行干预。药物干预4周后利用超声心动图评估心功能变化；采用苏木素-伊红（hematoxylin-eosin，HE）和Masson染色评价心脏病理损伤及纤维化程度；采用心脏指数、心脏质量与胫骨长度比值、小麦胚芽凝集素（wheat germ agglutinin，WGA）染色评价心脏重构和心肌细胞肥大程度；采用血清生化检测、qRT-PCR、Western blotting及免疫荧光染色等技术检测HF相关标志物及Piezo1/NO通路关键蛋白的表达变化。结果 YQFM显著改善TAC诱导的小鼠心功能障碍与心脏重构（P＜0.05、0.01），并减轻组织结构紊乱、心肌细胞肥大和心肌纤维化（P＜0.01）。机制研究表明YQFM降低血清心肌损伤标志物心肌肌钙蛋白T（cardiac troponin T，cTn-T）、N末端B型利钠肽前体（N-terminal pro-B-type natriuretic peptide，NT-proBNP）水平（P＜0.01），显著下调心脏中肥大相关基因心房钠尿肽（natriuretic peptide A，Nppa）、B型利钠肽（natriuretic peptide B，Nppb）、肌球蛋白重链7（myosin heavy chain 7，Myh7）与纤维化相关基因I型胶原蛋白α1链（collagen type I alpha 1 chain，Col1a1）、Ⅲ型胶原蛋白α1链（collagen type III alpha 1 chain，Col3a1）的表达（P＜0.05、0.01）。YQFM还可显著降低卵泡抑素样蛋白1（follistatin-like 1，Fstl1）和内皮素-1（endothelin-1，ET-1）含量（P＜0.05、0.01），同时提升血清与心脏组织中NO及环磷酸鸟苷（cyclic guanosine monophosphate，cGMP）水平（P＜0.01）。此外，YQFM显著上调心脏内皮细胞中Piezo1蛋白与磷酸化内皮型一氧化氮合酶（phosphorylated endothelial nitric oxide synthase，p-eNOS）的表达（P＜0.01）。结论 YQFM通过上调内皮Piezo1表达并激活eNOS/NO通路，改善心脏功能与重构，抑制心肌细胞肥大，从而发挥抗HF作用。

Objective To investigate whether Yiqi Fumai Lyophilized Injection [注射用益气复脉（冻干）, YQFM] ameliorates myocardial hypertrophy and pressure overload-induced heart failure (HF) by upregulating the cardiac endothelial mechanosensitive ion channel Piezo1 and activating the nitric oxide (NO) signaling pathway. Methods A mouse HF model was prepared via transverse aortic constriction (TAC) surgery. Two weeks post-operation, mice received intraperitoneal injections of different doses of YQFM (0.13, 0.26, 0.53 g/kg) or captopril (20 mg/kg) for four weeks. Cardiac function was assessed by echocardiography. Pathological injury and fibrosis were evaluated by hematoxylin and eosin (HE) and Masson staining. Cardiac remodeling and cardiomyocyte hypertrophy were assessed by heart index, heart weight-to-tibia length ratio and wheat germ agglutinin (WGA) staining. Serum biochemical assays, qRT-PCR, Western blotting and immunofluorescence were employed to detect HF-related biomarkers and the expressions of key proteins in Piezo1/NO pathway. Results YQFM significantly improved TAC-induced cardiac dysfunction and remodeling (P < 0.05, 0.01), and alleviated histopathological disorganization, cardiomyocyte hypertrophy and myocardial fibrosis (P < 0.01). Mechanistic studies showed that YQFM reduced levels of cardiac injury markers cardiac troponin T (cTn-T) and N-terminal pro-B-type natriuretic peptide (NT-proBNP) in serum (P < 0.01), and significantly downregulated the expressions of hypertrophy-related genes natriuretic peptide A (Nppa), natriuretic peptide B (Nppb), myosin heavy chain 7 (Myh7) and fibrosis-related genes collagen type I alpha 1 chain (Col1a1), collagen type III alpha 1 chain (Col3a1) in cardiac tissue (P < 0.05, 0.01). YQFM significantly decreased the levels of follistatin-like 1 (Fstl1) and endothelin-1 (ET-1) (P < 0.05, 0.01), while elevating the levels of NO in serum and cardiac tissue and cyclic guanosine monophosphate (cGMP) in cardiac tissue (P < 0.01). Furthermore, YQFM significantly upregulated the expressions of Piezo1 protein and phosphorylated endothelial nitric oxide synthase (p-eNOS) in cardiac endothelial cells (P < 0.01). Conclusion YQFM improves cardiac function and remodeling, and inhibits cardiomyocyte hypertrophy in HF by upregulating endothelial Piezo1 expression and activating eNOS/NO signaling pathway.

R285.5

国家自然科学基金面上项目（82274140）