MLK3/JNK介导巨噬细胞极化在心力衰竭心肌纤维化中的作用及益气养阴活血法的干预

Heart failure is a common clinical critical condition and belongs to the category of heart impediment , phlegm and retained fluid in Chinese medicine. It has become an important public health issue in the field of cardiovascular disease because of the high incidence and difficult treatment. Myocardial fibrosis is the most important pathological feature of heart failure, and the surrounding microenvironment such as macrophage polarization plays a key role in it. It has been reported that MLK3/JNK mediates fibroblast activation and promotes fibrosis. Our previous study found that MLK3 levels were up-regulated in hearts with heart failure and correlated with macrophage polarization. While Xinyin tablet，a representative prescription of tonifying qi, nourishing yin and activating blood method could inhibit MLK3 and alleviate myocardial fibrosis, but the exact mechanism remains to be further studied. This project intends to use transgenic animal, flow cytometry, adenovirus transfection and other methods to study the macrophages M1 / M2 phenotype transformation in cardiac fibrosis via the animal and cell models. To clarify the role of MLK3 / JNK-mediated macrophage polarization in myocardial fibrosis in heart failure and the effect of tonifying qi, nourishing yin and activating blood method in preventing and treating myocardial fibrosis by regulating the mechanism. This project is of great theoretical value for further exploring the mechanism of traditional Chinese medicine in preventing and treating myocardial fibrosis in heart failure, finding new targets for improving prevention and treatment.

心力衰竭是临床常见危重症候，属中医心痹、痰饮范畴，治疗困难、发病率高，已成为心血管病领域的重要公共卫生问题。心肌纤维化是其最重要的病理特点，但发病机制复杂，周围微环境如巨噬细胞极化在其中起到关键作用。据报道MLK3/JNK可介导成纤维细胞激活促进纤维化，我们前期研究发现心力衰竭心脏中MLK3水平上调，且与巨噬细胞极化相关，而益气养阴活血法代表方心阴片治疗心力衰竭疗效明显，与抑制MLK3，减轻心肌纤维化有关，但具体作用机制仍待深入研究。本项目拟采用转基因动物、流式细胞术、腺病毒转染等方法技术，从动物和细胞水平探讨巨噬细胞M1/M2表型在心肌纤维化进程中的转变，阐明MLK3/JNK介导巨噬细胞极化在心力衰竭心肌纤维化中的作用，以及益气养阴活血法通过调节该机制防治心肌纤维化的作用机制，对深入研究中医药防治心力衰竭心肌纤维化的机理，寻找防治新靶点，提高防治水平，具有重要的理论价值。

心力衰竭是临床常见危重症候，属中医心痹、痰饮范畴，治疗困难、发病率高，已成为心血管病领域的重要公共卫生问题。心肌纤维化是其最重要的病理特点，但发病机制复杂，周围微环境如巨噬细胞极化在其中起到关键作用。据报道MLK3/JNK可介导成纤维细胞激活促进纤维化，我们前期研究发现心力衰竭心脏中MLK3水平上调，且与巨噬细胞极化相关，而益气养阴活血法代表方心阴片治疗心力衰竭疗效明显，与抑制MLK3，减轻心肌纤维化有关，但具体作用机制仍待深入研究。本项目以MLK3、巨噬细胞极化为靶点，研究益气养阴活血法通过调节MLK3/JNK介导巨噬细胞极化防治心力衰竭心肌纤维化的作用机制，采用心脏超声、Masson染色、免疫荧光共染、流式细胞术、Western Blot、Q-PCR等方法技术，动态观察了抑制MLK3后对TAC心衰小鼠不同时期心功能的影响及对炎症浸润及巨噬细胞募集进行了检测，另通过给予小鼠尾静脉注射腺相关病毒来敲除MLK3，给予心阴片干预，检测相关指标，探讨了益气养阴活血法代表方心阴片调节MLK3/JNK介导巨噬细胞极化减轻心力衰竭心肌纤维化的作用机制。研究发现抑制MLK3后早期能够抑制急性炎症损伤，抑制M1巨噬细胞募集，而晚期则抑制JNK信号通路对M2巨噬细胞的募集，减少胶原沉积降低心肌纤维化，同时发现心阴片能够抑制MLK3表达，改善心功能及胶原沉积，其机制可能是早期通过抑制MLK3表达进而抑制炎症反应，减少M1型巨噬细胞激活，晚期则是减少M2型巨噬细胞激活。本项目相关研究目前已发表学术论文3篇，协助培养博士研究生一名。本项目的研究对深入研究中医药防治心力衰竭心肌纤维化的机理，寻找防治新靶点，提高防治水平，具有重要的理论价值。