Jatrorrhizine reduces myocardial infarction-induced apoptosis and fibrosis through inhibiting p53 and TGF-β1/Smad2/3 pathways in mice

Purpose:  To explore the mechanism of jatrorrhizine on apoptosis and fibrosis induced by myocardial infarction (MI) in an animal model.

Methods:  The left anterior descending branch of coronary artery was surgically ligated to duplicate the mouse model of MI. The sham and infarcted mice were treated with normal saline once a day, while mice in experimental groups received low-dose (LD) and high-dose (HD) jatrorrhizine once a day respectively. Two weeks later, cardiac function was detected by echocardiography, and histopathological examination was performed using hematoxylin and eosin (H&E) and Masson staining. The expressions of p53, TGF-β1, Smad/2/3, Bax, Bcl-2, collagen I and collagen III were quantified using qRT-PCR and western blot assays.

Results:  Jatrorrhizine significantly improved left ventricular ejection fraction (LVEF) and left ventricle end-systolic (LVES) in mice. Histopathological, administration of jatrorrhizine weakened infiltration of inflammatory cells and cardiac fibrosis in myocardium of mice caused by MI. Additionally, jatrorrhizine suppressed cardiomyocyte apoptosis exhibited as its capability to reverse changes of Bax and Bcl-2 levels in myocardium caused by MI. Jatrorrhizine statistically significantly downregulated expression of collagen I and collagen III, as well as TGF-β1, Smad2/3 and p53.

Conclusions:  Jatrorrhizine reduce cardiomyocyte apoptosis and fibrosis through inhibiting p53/Bax/Bcl-2 and TGF-β1/Smad2/3 signaling pathways.

Key words
Alkaloid; Myocardial Infarction; Apoptosis; Fibrosis; Mice