CaMKII调控舒张性心衰的作用机制及益气活血法的干预作用

According to the global epidemiological survey, the prevalence of heart failure with preserved ejection fraction (HFpEF) accounts for about 50% of the total number of heart failures. It is expected to reach 65% in 2020, but its target drug research is in slow progress. The exact dilemma is that the future HFpEF prevention and control situation is severe. CaMKII-mediated abnormal calcium homeostasis is an important pathological mechanism for the development of HFpEF. Previous research conducted by our team showed that Yiqihuoxue formula can improve myocardial cell calcium homeostasis and improve myocardial cell diastolic function, but its deep molecular mechanism is still unclear. Therefore, this study intends to use Yiqi Huoxue Recipe (Huangqi + Dangshen + Sanqi + Salvia miltiorrhiza) and CaMKII inhibitor KN-93 to intervene in CaMKIIδB and CaMKIIδC overexpressing Tg mice, and compare the structure and relaxation function of the two in the whole heart and myocardial cells. , ventricular muscle remodeling, myocardial cell calcium homeostasis, cardiac hypertrophy and calcium homeostasis related genes and protein expression levels difference in efficacy, in order to reveal the deep pathological mechanism of CaMKII regulation of HFpEF, further verify the intervention of Yiqihuoxue method on HFpEF, Explain its scientific connotation and micro-control mechanism.

全球流行病学调查显示，射血分数保留的心衰HFpEF患病率约占心衰总数的50%，预计2020年将达65%，但其靶点药物研究处于探索困难、进展缓慢、疗效不确切的窘境，未来HFpEF防治形势严峻。CaMKII介导的钙稳态异常是HFpEF发生发展的重要病理机制。课题组前期研究表明益气活血法可改善心肌细胞钙稳态，改善心肌细胞舒张功能，但其深层分子机制尚不明确。故本研究拟采用益气活血方（黄芪+党参+三七+丹参）及CaMKII抑制剂KN-93干预CaMKIIδB、CaMKIIδC过表达转基因小鼠，比较两者在心脏整体及心肌细胞结构、舒缩功能，心室肌重塑，心肌细胞钙稳态，心肌肥厚及钙稳态相关基因及蛋白表达水平的疗效差异，以揭示CaMKII调控HFpEF的深层病理机制，进一步验证益气活血法对HFpEF的干预作用，阐释其科学内涵和微观调控机理。

射血分数保留的心衰（HFpEF）患病率约占心衰总数的50%，尚无疗效确切的药物，防治形势严峻。CaMKII介导的钙稳态异常是HFpEF发生发展的重要病理机制。课题组前期研究表明益气活血法可改善心肌细胞钙稳态，改善心肌细胞舒张功能，但其深层分子机制尚不明确。本研究拟采用益气活血方（黄芪+党参+三七+丹参，益气：活血比例为2:1）及CaMKII抑制剂KN93干预CaMKIIδB、CaMKIIδC过表达转基因小鼠，比较两者在心脏整体及心肌细胞结构、舒缩功能，心室肌重塑，心肌细胞钙稳态，心肌肥厚及钙稳态相关基因及蛋白表达水平的疗效差异，以揭示CaMKII调控HFpEF的深层病理机制，进一步验证益气活血法对HFpEF的干预作用，阐释其科学内涵和微观调控机理。.本研究最终成功构建了CaMKⅡδC过表达致HFpEF模型，及CaMKⅡδB、CaMKⅡδC过表达致射血分数降低的心衰（HFrEF）模型。完成重用益气的益气活血法（党参、黄芪、丹参、三七）对CaMKIIδC条件性过表达致HFpEF的药效及机制研究，证明益气活血中药可能通过抑制CaMKⅡδC过表达，提高SERCA2a蛋白、PLB-T17磷酸化水平，增加钙回摄功能（体现在降低消除时间常数、增加钙库容量、减少钙泄漏），最终改善HFpEF舒张功能。完成了重用益气的益气活血法（党参、黄芪、丹参、三七）对CaMKIIδB、CaMKIIδC条件性过表达致HFrEF的药效及机制研究，证明益气活血中药改善CaMKIIδB、CaMKIIδC过表达所致HFrEF的机制：可能与其抑制CaMKIIδB的过表达，提高SERCA2a蛋白水平，增加心肌细胞收缩力、增加钙回摄及钙储备，并减少肥大相关因子的表达有关;可能与其抑制CaMKIIδC的过表达，提高SERCA2a蛋白、PLB-T17磷酸化水平，增加心肌细胞收缩力、增加钙回摄及钙储备、减少钙泄漏有关。.本研究证明心肌细胞关键激酶CaMKII调控的钙稳态与收缩性及舒张性心衰的发生均密切相关，重用益气药物的益气活血方可通过抑制CaMKII过表达，改善心肌细胞钙稳态，从而对HFpEF和HFrEF均起到治疗作用。揭示了气虚血瘀为心衰基本病机的深层科学内涵，体现了中医“异病同治”的理论特色，为中医临床治疗心衰提供了实验室依据和深层研究方向。