The effect of angoroside C on pressure overload-induced ventricular remodeling in rats

Background: Our previous study reveals that total rough extract of Radix Scrophulariae has a beneficial effect on ventricular remodeling.

Hypothesis: After carrying out a series of preliminary experiments, we speculated that angoroside C may be the effective agent.

Study design: After oral administration, the effect of angoroside C on ventricular remodeling was evaluated by using a pressure-overloaded rat model, some related indexes were detected in vivo.

Methods: A model of pressure overloaded ventricular remodeling was produced by abdominal aortic constriction (AAC) in rats. The sham-operated rats underwent an identical surgical procedure except for AAC. AAC rats were randomly divided into five groups: model control group, three angoroside C treated groups (7.5, 15 and 30 mg·kg(-1)) and captopril treated group (40 mg·kg(-1)). The rats were orally administered with the corresponding drugs or drinking water for 4 weeks. The levels of blood pressure (BP), left ventricular weight index (LVWI) and heart weight index (HWI) were detected. Myocardium tissue was stained with hematoxylin and eosin or picric acid/sirius red for cardiomyocyte cross-section area or collagen content measurements respectively. The concentrations of angiotensin Ⅱ (Ang Ⅱ), hydroxyproline (Hyp), matrix metalloproteinase 2 (MMP-2), MMP-9 and tissue inhibitor of metalloproteinase-1 (TIMP-1) in myocardium or serum were determined. Real-time RT-PCR was performed to detect the mRNA expressions of endothelin 1 (ET-1), transforming growth factor β1 (TGF-β1).

Results: Angoroside C significantly reduced the BP, LVWI and HWI, decreased the content of Ang Ⅱ, Hyp, diminished cross sectional area of cardiomyocytes and ameliorated collagen deposition. Additionally, it markedly reduced collagen I and III expressions and regulated matrix metalloproteinase-2, 9 and inhibitors of metalloproteinase expressions. Angoroside C also down regulated the gene expressions of ET-1 and TGF-β1mRNA in myocardium.

Conclusion: Angoroside C has beneficial effects against ventricular remodeling. The mechanism is likely to be related to decreasing the level of Ang Ⅱ, attenuating the mRNA expressions of ET-1 and TGF-β1.