To investigate the effects of Luhong Yixin Granules on myocardial fibrosis in rats with heart failure and its possible mechanism, a total of 60 male Wistar rats were randomly divided into the control group, model group, and low-, medium-and high-dose Luhong Yixin Granules groups, with 12 rats in each group. Except for those in the control group, rats in the other groups were induced by intraperitoneal injection of doxorubicin(DOX) into a rat model. After the Luhong Yixin Granules were dissolved in the same amount of normal saline, they were given by gavage at low, medium and high doses(2.8, 5.6, 11.2 g·kg~(-1)·d~(-1)), and the control group and the model group were given the same amount of normal saline by gavage for 40 days. After the end of dosing, echocardiography was used to measure left ventricular ejection fraction(LVEF) and left ventricular fractional shortening(LVFS). Rat body weight(BW) and heart weight(HW) were calculated as HW/BW. Enzyme-linked immunosorbent assay was used to measure the levels of interleukin-6(IL-6), interleukin-17(IL-17), tumor necrosis factor-α(TNF-α), transforming growth factor-β1(TGF-β1), growth stimulation expressed gene 2 protein(ST2), N-terminal pro-B-type natriuretic peptide(NT-proBNP), galectin-3(Gal-3) and creatine kinase isoenzyme(CK-MB) in serum. Hematoxylin-eosin(HE) staining and Masson staining were used to observe the pathological morphology of myocardial tissue. Western blot and quantitative real-time polymerase chain reaction were used to detect the protein and mRNA expression levels of IL-6, IL-17, TNF-α, TGF-β1, Smad3, Smad7, α-smooth muscle actin(α-SMA), and collagen Ⅰ(COL-Ⅰ), respectively. RESULTS:: showed that compared with those in the control group, LVEF, LVFS, and HW/BW in the model group were decreased(P<0.05), and the levels of IL-6, IL-17, TNF-α, TGF-β1, ST2, NT-proBNP, Gal-3, and CK-MB were increased(P<0.05). HE staining showed inflammatory changes in myocardial tissue; Masson staining showed decreases in the cross-sectional area and ventricular cavity area of the heart, and myocardial fibrosis of varying degrees(P<0.05). The protein and mRNA expression of IL-6, IL-17, TNF-α, TGF-β1, Smad3, α-SMA, and COL-Ⅰ were increased(P<0.05), and the protein and mRNA expression of Smad7 protein was decreased(P<0.01). Compared with those in the model group, LVEF, LVFS and HW/BW of the low-, medium-and high-dose Luhong Yixin Granules groups were increased(P<0.05), and the levels of IL-6, IL-17, TNF-α, TGF-β1, ST2, NT-proBNP, Gal-3 and CK-MB were decreased(P<0.05). HE staining showed gradually reduced inflammatory changes of myocardial tissue, and Masson staining showed increased cross-sectional area and ventricular cavity area of the heart and decreased area of myocardial fibrosis(P<0.05). The protein and mRNA expression levels of IL-6, IL-17, TNF-α, TGF-β1, Smad3, α-SMA, and COL-Ⅰ were decreased(P<0.05), while the protein and mRNA expression levels of Smad7 were increased(P<0.05). Luhong Yixin Granules may be of great value in the treatment of heart failure by regulating the TGF-β1/Smads signaling pathway, inhibiting the expression of inflammation-related proteins, reducing the deposition of extracellular matrix, and alleviating myocardial fibrosis.
