Author + information
- 1Modern Research Center for Traditional Chinese Medicine, Beijing University of Chinese Medicine
- 2School of Chinese Materia Medica, Beijing University of Chinese Medicine
- 3Center of Scientific Experiment, Beijing University of Chinese Medicine
- 4School of Life Sciences, Beijing University of Chinese Medicine
Baoyuan Decoction (BYD), a classical Chinese formula, has been well documented for its anti-myocardial ischemic efficacy in ancient China and has widely been used in the treatment of heart failure in clinical nowadays. However, the underlying molecular mechanism of BYD for heart failure remains unknown. The present study aims to investigate that whether BYD treatment can reduce cardiac hypertrophy and inhibit myocardial apoptosis in heart failure rats and the role of cardiac ankyrin repeat protein (CARP) in this process.
Sprague-Dawley (SD) rats were randomly divided into 6 groups including sham group, model group (left anterior descending coronary artery ligation), EGb761 positive control group, BYD low-dose group, BYD middle-dose group, and BYD high-dose group. 7 days after treatment, hemodynamic and heart function were both detected. HE and Masson’s trichrome staining were performed to assess the degree of myocardial hypertrophy and fibrosis. Myocardial apoptosis rate was detected by TUNEL assay. Expression of critical proteins as CARP, p53, MDM2, proBNP, AT1, and mitochondrial apoptotic pathway (Bax, bcl-2 and cleaved caspase-3) were determined by Western blot. In vitro, apoptosis and remodeling models in H9c2 cardiomyocytes were induced by OGD/R and AngII respectively. Different dosages of BYD (400μg/ml, 600μg/ml, and 800μg/ml) were added accordingly in each group with the RNH-6270, the antagonist of AT1, as the positive drug. Level of CARP were assayed by immunofluorescence. Protein expressions of CARP, proBNP and AT1 were measured by Western blot as previously described.
Echocardiography results showed that LVEDd and LVEDs in the model group were larger than that in sham group, indicating the induction of ventricular remodeling. Results of HE and Masson’s trichrome staining also demonstrated pathological changes of hypertrophy. Expressions of heart failure biomarker, proBNP and hypertrophy markers, AT1 and CARP, were dramatically elevated in model group compared to sham group. Western blot results showed that p53, which is highly inducible by CARP, increased significantly, while MDM2, the inhibitor of p53, decreased in model group. Increased expressions of mitochondrial apoptotic pathway factors, including Bax and cleaved caspase-3 were also observed. MTT and Hoechst showed that CARP overexpression significantly reduced cell viability and increased apoptosis of H9c2 in the presence of AngII stimulation or OGD/R, suggesting the apoptosis was at least partly mediated by CARP. After treatment of BYD, expressions of CARP, AT1 and proBNP were reduced both in vivo and vitro. BYD could also suppress the expressions of p53, Bax and cleaved caspase-3, suggesting that CARP-p53 mediated apoptosis was inhibited by BYD.
BYD has definite cardioprotective effect on attenuating cardiac remodeling and improving heart dysfunction mainly through inhibiting the expression of CARP and subsequent reduction of p53-related apoptosis. These findings provide evidence for beneficial effects of BYD in the clinical application for heart failure.