Cardioprotection against Heart Failure by Shenfu Injection via TGF- β/Smads Signaling Pathway

Abstract

Objective: To explore the potential cardioprotective mechanism of Shenfu injection (SFI) against heart failure (HF) by attenuating myocardial fibrosis and cardiac remodeling.

Methods and results: Four weeks after myocardial infarction (MI), adult male Sprague Dawley rats were randomized for 4-week treatment with Valsartan, SFI, or vehicle. Echocardiography and hemodynamics were applied to evaluate cardiac functions. Myocardia of coronary artery ligated (CAD) rats were observed to investigate changes in cardiac structure and function. Our findings suggest that treatment with SFI could inhibit progression of myocardial fibrosis and attenuate cardiac remodeling. In addition, SFI decreased expression of Smad2 and Smad3, while increasing the expression of Smad7 through regulation of TGF-β/Smads signaling pathway.

Conclusion: Treatment with SFI in Sprague Dawley rats improves ventricular structure and function and reduces cardiac fibrosis by ameliorating TGF-β/Smads signaling pathway after ventricular remodeling.

Figure 1

Echocardiographic characterization of cardiac systolic function in rats subjected to HF. Notes. Quantitative assessment of dilation and systolic function based on LVEF (a), LVFS (b), AV Peak V (c), LVIDs (d), LV systolic volume (LV Vols) (e), and LVPWs (f). Data are expressed as mean ± SD from ten animals. ^∗∗P < 0.01 compared with the sham group; ^#P < 0.05 and ^##P < 0.01 compared with the HF group.

Figure 2

Representative echocardiographic images (M-mode) in different groups. Notes. (a) Sham group, (b) HF group, (c) Valsartan + HF group, (d) SFI 1.5 mL/kg + HF group, and (e) SFI 0.75 mL/kg + HF group. HF, heart failure; SFI, Shenfu injection.

Figure 3

Representative transmitral valvular flow profiles and the color images acquired by color Doppler ultrasonography after 4-week drug administration, where the white shadow represents the aortic flow velocity. Notes. (a) Sham group, (b) HF group, (c) Valsartan + HF group, (d) SFI 1.5 mL/kg + HF group, and (e) SFI 0.75 mL/kg + HF group. HF, heart failure; SFI, Shenfu injection.

Figure 4

Hemodynamic assessment was performed to the left ventricle through right carotid artery to evaluate the role of SFI treatment in the management of HF. Notes. Quantitative assessment of hemodynamic on cardiac function based on HR (a), LVP (b), LVSP (c), LVEDP (d), +dp/dt_max (e), and −dp/dt_min (f). Data are expressed as mean ± SD from eight animals. ^∗∗P < 0.01 compared with the sham group; ^#P < 0.05 and ^##P < 0.01 compared with the HF group.

Figure 5

The experimental study of expression for Shenfu injection on myocardial miRNAs in rats with chronic congestive heart failure. (a) The intersection diagram of differentially expressed miRNA in three experiment groups. (b) Statistical analysis of seven miRNA expression differences in heart failure (n = 3). (c–e) GO analysis of differential genes. Notes. Compared with the sham group, ^∗∗P < 0.01; compared with model group, ^#P < 0.05 and ^##P < 0.01.

Figure 6

The effect of SFI on the content of NT-proBNP, TGF-β1, MMP-9, and CTGF of rat serum. Notes. Statistical results from ELISA for NT-proBNP (a), TGF-β1 (b), MMP-9 (c), and CTGF (d). Data are expressed as mean ± SD from ten animals. ^∗∗P < 0.01 compared with the sham group; ^#P < 0.05 and ^##P < 0.01 compared with the HF group. NT-proBNP, N-terminal probrain natriuretic peptide; TGF-β1, transforming growth factor-beta 1; MMP-9, matrix metalloproteinase-9; CTGF, connective tissue growth factor; SD, standard deviation; HF, heart failure; SFI, Shenfu injection.

Figure 7

The effect of SFI treatment on myocardial pathology in rats with HE staining after 4 weeks. Notes. (a) Sham group, (b) HF model group, (c) Valsartan + HF group, (d) SFI 1.5 mL/kg + HF group, and (e) SFI 0.75 mL/kg + HF group. Bar, 100 μm. HF, heart failure; SFI, Shenfu injection; HE, hematoxylin-eosin.

Figure 8

The effect of SFI treatment on left ventricular myocardial fibrosis in rats with Masson trichrome staining after 4 weeks. Notes. (a) Sham group, (b) HF model group, (c) Valsartan + HF group, (d) SFI 1.5 mL/kg + HF group, and (e) SFI 0.75 mL/kg + HF group. Myocardium was stained red and collagens were stained blue. Bar, 100 μm. HF, heart failure; SFI, Shenfu injection.

Figure 9

SFI regulates expression of TGF-β1, Smad2, Smad3, and Smad7 mRNA in rat hearts. Notes. The relative levels of cardiac TGF-β1 (a), Smad2 (b), Smad3 (c), and Smad7 (d) mRNA were assessed by real-time PCR. Results were normalized to GAPDH. Data are expressed as mean ± SD (each group, n = 3). ^∗∗P < 0.01 compared with the sham group; ^#P < 0.05 and ^##P < 0.01 compared with the HF model group. SFI, Shenfu injection; HF, heart failure; SD, standard deviation; PCR, polymerase chain reaction; GAPDH, glyceraldehyde-3-phosphate dehydrogenase; TGF-β1, transforming growth factor-beta 1.