Apelin/APJ及其信号通路在针刺减轻心肌缺血再灌注损伤中的作用

Myocardial ischemia reperfusion injury (I/R) is a common clinical pathological and physiological phenomenon. Acupuncture therapy has better clinical effect on myocardial I/R injury. In our previously studies, we found that acupuncture could promot recovery after operation in cardiac operation in clinical research. Recently, we also found that acupuncture can effectively improve the inflammation by inhibiting the ERK1/2 pathway and the area of myocardial infarction induced by I/R. Apelin/angiotensin receptor-like protein J receptor (APJ) signaling is present in the cardiovascular system tissues and plays a critical role in modulating multiple aspects of physiology and pathophysiology. This study is designed to investigate the effect of electroacupunture (EA) on Apelin/APJ signaling in a rat model of cardiopulmonary bypass (CPB), while the acupoint of Neiguan (GB34) is used. The changes of myocardial function, myocardial structure and energetic metabolism were observed to evaluate the cardioprotective effects of EA treatment. The expression change of Apelin and APJ in heart tissue will also be examined after EA treatment in rat with myocardial I/R model. Furthermore, the ERK1/2 pathway and PI3K/Akt pathway, which are the mainly downstream signaling pathways of Apelin-APJ signaling, will be examined that whether they have special regulations by EA stimulation in this pathological condition. Meanwhile, Apelin and APJR knockout mice, combined with modern molecular biology techniques, are also used to systematically identify whether the Apelin-APJ system is a potential EA therapeutic target in vitro protective effects and mechanisms in the circulation after myocardial I/R injury. This study would potentially help clinicians to further understand the mechanism of “acupuncture - organ protection effect ", and provide scientific basis for clinical application and promotion in clinical acupuncture using.

心肌缺血再灌注损伤（I/R）是临床常见的病理生理现象，针刺治疗具有较好的临床效应。我们前期在临床研究表明针刺在心脏手术中促进患者的术后恢复，同时基础研究均表明针刺可通过抑制ERK1/2通路有效改善心肌I/R所致的炎症和心肌梗死面积。本课题以心肌I/R小鼠为模型，通过不同频率电针针刺大鼠“内关”穴， 通过系统检测大鼠心功能、心肌结构、心肌能量代谢和炎症因子生成，综合评价针刺对心肌I/R小鼠心脏保护效应。并在此基础上，系统观察针刺对心肌I/R后心Apelin /APJ表达及其下游ERK1/2和PI3K/Akt信号通路的影响。同时，利用Apelin/APJ 通路基因敲除小鼠和药理学等多种方法，阐明Apelin/APJR 系统及其下游信号通路在心肌I/R中的保护作用及机制。本研究将揭示 “针刺脏器保护相关效应”的内在生物学机制，为临床针刺的临床应用和推广提供实验依据。

心肌缺血再灌注损伤（I/R）是临床常见而有待于解决的关键问题。我们前期在临床和基础研究表明针刺应对心肌I/R具有良好的保护效应，但是机制尚不十分清楚。Apelin/APJ系统在体内广泛分布，尤其是在心血管内皮细胞和心脏组织，具有重要的心血管生理和病理生理调节作用。前期研究提示针刺可以调节机体Apelin/APJ发挥效应。因此，本课题探寻Apelin/APJ系统是否介导了针刺抗心肌I/R的保护效应。本课题结果发现：（1）针刺预处理可有效抑制心肌I/R大鼠的心肌梗死面积和心肌细胞凋亡率；（2）心肌I/R造模后，大鼠血浆中心肌损伤标志物心肌肌钙蛋白（cTnI）和乳酸脱氢酶（LDH）含量明显上升，针刺预处理组大鼠血浆中cTnI和LDH的含量显著低于心肌I/R模型组；（3）针刺预处理抑制心肌缺血再灌注损伤大鼠的心肌氧化应激反应，提高心肌I/R大鼠心肌组织中还原型谷胱甘肽（GSH）/氧化型谷胱甘肽（GSSG）的比值；（4）针刺预处理可抑制心肌缺血再灌注损伤大鼠的心肌炎症反应，抑制心肌组织中髓过氧化物酶（MPO）活性及促炎细胞因子IL-1β和TNFα的水平；（5）针刺预处理可显著抑制apelin和APJ的表达下调，以及下游重要分子p-Akt和p-Erk1/2的水平；（6）建立体外循环（CPB）模型，发现针刺预处理效应同样可以促进apelin和APJ的表达恢复；（7）给予Apelin/APJ系统拮抗剂F13A能拮抗针刺预处理的心肌保护效应。通过本研究，揭示Apelin/APJ系统参与介导了针刺预处理在抗心肌I/R中的保护作用。为“针刺脏器保护相关效应”的内在生物学机制提供了相关的理论依据，为临床针刺的临床应用和推广提供实验依据。