Linggui Qihua Decoction Inhibits Atrial Fibrosis by Regulating TGF‐β1/Smad2/3 Signal Pathway

Myocardial fibrosis is a critical factor in the development of heart failure with preserved ejection fraction (HFpEF). Linggui Qihua decoction (LGQHD) is an experienced formula, which has been proven to be effective on HFpEF in clinical and in experiments. Objective . This study aimed to observe the effect of LGQHD on HFpEF and its underlying mechanism. Methods . Spontaneously hypertensive rats (SHR) were induced with high‐glucose and high‐fat to establish HFpEF models and were treated with LGQHD for 8 weeks. The heart structure was detected by echocardiography, and the histopathological changes of the myocardium were observed by hematoxylin‐eosin (HE) and Masson staining. Reverse transcription PCR (RT‐PCR) and western blot were used to detect mRNA and protein expression of the target gene in rat myocardium. Results . In this study, LGQHD improved cardiac morphology and atrial fibrosis in HfpEF rats, decreased tissue inhibitor of metalloproteinase‐1 (TIMP‐1) mRNA expression, up‐regulated matrix metalloproteinase‐9 (MMP‐9) mRNA expression, and inhibited the expression of angiotensin II (Ang II), angiotensin II type 1 receptor (AT1), transforming growth factor β 1 (TGF‐ β 1), Smad2/3 mRNA, and protein in myocardial tissue of HFpEF rats. Conclusion . LGQHD can suppress atrial fibrosis in HFpEF by modulating the TGF‐ β 1/Smad2/3 pathway.