Injection of YiQiFuMai powder protects against heart failure via inhibiting p38 and ERK1/2 MAPKs activation

Injection of YiQiFuMai (YQFM) powder, a modern Chinese plant-derived medical preparation, has a therapeutic effect in heart failure (HF). However, its therapeutic mechanism remains largely unknown.
To investigate the molecular mechanisms of YQFM in HF.
Kinase inhibition profiling assays with 2 mg/mL YQFM were performed against a series of 408 kinases. In addition, the effects of kinase inhibition were validated in cardiomyocyte cell line H9c2. In vivo, HF with reduced ejection fraction (HFrEF) was induced by permanent left anterior descending (LAD) coronary artery ligation for 6 weeks in male Sprague-Dawley rats. Then, HFrEF mice were treated with 0.46 g/kg YQFM or placebo once a day for 2 weeks. Echocardiography, immunohistochemistry, histological staining and Western blotting analysis were performed to assess the myocardial damage and molecular mechanisms.
Kinase inhibition profiling analysis demonstrated that mitogen-activated protein kinases (MAPKs) mediated the signalling cascades of YQFM during HF therapy. Meanwhile, p38 and extracellular signal-regulated kinases (ERK1/2) were inhibited after YQFM treatment in H9c2 cells. In rats, the control group had lower left ventricular ejection fraction (LVEF) at 37 ± 1.7% compared with the YQFM group at 54 ± 1.1% (p < 0.0001). Cardiac fibrosis levels in control group rats were significantly higher than YQFM group (30.5 ± 3.0 vs. 14.1 ± 1.0, p < 0.0001).
Our collective in vitro and in vivo experiments demonstrated that YQFM improves left ventricular (LV) function and inhibits fibrosis in HFrEF rats by inhibiting MAPK signalling pathways.