Danqi soft capsule administered for 4 weeks significantly attenuated tachyarrhythmia induction rates, arrhythmia scores, and infarct border zone remodelling in post-myocardial infarction rats.
Does Danqi soft capsule prevent infarct border zone remodelling and reduce susceptibility to ventricular arrhythmias in post-myocardial infarction rats?
Danqi soft capsule regulates interstitial fibrosis and myocyte hypertrophy via the TGF-β1/Smad3 pathway, inhibiting left ventricular remodeling and reducing vulnerability to tachyarrhythmias after myocardial infarction in a rat model.
Danqi soft capsule (DQ) is a traditional Chinese medicine containing Salvia miltiorrhiza and Panax notoginseng; it is safe and efficient in treating ischaemic heart diseases. The purpose of the present study was to assess whether DQ could prevent infarct border zone (IBZ) remodelling and decrease ventricular arrhythmias occurrence in post-myocardial infarction (MI) stage. MI was induced by a ligation of the left anterior descending coronary artery. DQ was administered to the post-MI rats started from 1 week after MI surgery for 4 weeks. The results showed that DQ treatment significantly attenuated tachyarrhythmia induction rates and arrhythmia score in post-MI rats. In echocardiography, DQ improved left ventricular (LV) systolic and diastolic function. Histological assessment revealed that DQ significantly reduced fibrotic areas and myocyte areas, and increased connexin (Cx) 43 positive areas in IBZ. Western blot revealed that DQ treatment significantly reduced the protein expression levels of type I and III collagens, α-smooth muscle actin (α-SMA), transforming growth factor-β1 (TGF-β1) and Smad3 phosphorylation, while increasing Cx43 amounts. Overall, these findings mainly indicated that DQ intervention regulates interstitial fibrosis, Cx43 expression and myocyte hypertrophy by TGF-β1/Smad3 pathway in IBZ, inhibits LV remodelling and reduces vulnerability to tachyarrhythmias after MI. This study presents a proof of concept for novel antiarrhythmic strategies in preventing IBZ remodelling, modifying the healed arrhythmogenic substrate and thus reducing susceptibility to ventricular arrhythmias in the late post-MI period.
Ma et al. (Mon,) conducted a other in Post-myocardial infarction. Danqi soft capsule (DQ) was evaluated on Tachyarrhythmia induction rates, arrhythmia score, and infarct border zone remodelling. Danqi soft capsule administered for 4 weeks significantly attenuated tachyarrhythmia induction rates, arrhythmia scores, and infarct border zone remodelling in post-myocardial infarction rats.