A study on myocardial fibrosis in rats with post-myocardial infarction heart failure based on Luofengning No. 2 in the transforming growth factor-β/Smads pathway

Abstract

Objective: The present study aims to observe the effects of Luofengning No. 2 on cardiac function, histopathology, and the transforming growth factor-β (TGFβ)/Smads pathway in rat models.Methods: A post-myocardial infarction heart failure (HF) model was constructed, and a total of 50 male Sprague Dawley rats were randomly divided into six groups: (1) the model group (n = 6), (2) the captopril group (n = 6), (3) the low-dose Luofengning No. 2 group (n = 6), (4) the medium-dose Luofengning No. 2 group (n = 7), (5) the high-dose Luofengning No. 2 group (n = 6), and (6) the sham operation group (n = 5). The serum N-terminal pro-brain natriuretic peptide (NT-proBNP) levels were detected using the enzyme-linked immunosorbent assay, and myocardial fibrosis (MF) was observed through Masson staining. In addition, the collagen volume fraction (CVF) was calculated, and the myocardial tissue TGFβ1, Smad2/3, collagen type I (Col-I), and collagen type III (Col-III) protein expressions were detected using Western blot testing.Results: The general conditions of the rats in the drug administration groups were improved, and the heart weight index, left ventricular weight index, and serum NT-proBNP levels were significantly lower compared with the model group (p<0.05 or p<0.01). Furthermore, the TGFβ1, Smad2/3, Col-I, collagen type III (Col-III), and CVF protein levels in the drug administration groups were significantly lower compared with the model group (p<0.05 or p<0.01). There existed no statistically significant differences in NT-proBNP levels; TGFβ1, Smad2/3, Col-I, and Col-III protein levels; or MF degrees between the captopril group and the high-dose Luofengning No. 2 group (p>0.05).Conclusion: Luofengning No. 2 might positively affect cardiac function and anti-MF improvement in rats with HF; this could be related to TGFβ1/Smad2/3.