Abstract 4039: Black Bean Extract Prevents Development of Cardiac Hypertrophy via Suppression of Collagen 1 and TGF-b in Cardiac Fibroblasts
Introduction: Inappropriate fibrosis is a hallmark of heart failure and recent evidence suggests a Black Bean Extract (BB) is capable of blocking fibrosis. We tested this extract in our mouse model of cardiac hypertrophy (CH) as well as cultured cardiac fibroblasts (CF).
Methods: CH was induced in C57BL6 mice by inclusion of 1% NaCl and 0.3 mg/ml L-NAME for 35 days and continuous delivers of 0.7 mg/kg/day of angiotensin II for 28 days. BB was delivered in the diet. Echocardiography was performed and hearts were removed for analysis in all three groups (Control, CH, CH+BB). For in vitro studies, CF were isolated from normal mouse hearts and grown in culture and serum starved for 12 hours followed by stimulation with fetal calf serum (FCS) with and without the addition of BB and real-time PCR used.
Results: The CH mouse demonstrated a 20% increase in mean arterial pressure which resulted in a >40% decrease in fractional shortening by echocardiography, a >25% increase in cardiac fibrosis by histology and significant increases in BNP, TNF-a, ET-1, TGF-b and Collagen 1 genes. The addition of BB significantly blocked the cardiac dysfunction, the fibrosis increase and the genes induced in the CH mouse to almost control levels. FCS stimulated TGF-b and collagen I production CF and inclusion of BB significantly decreased both the TGF-b and collagen I gene expression in culture.
Conclusion: Black Bean Extract is capable of inhibiting fibrosis and inflammatory markers in a mouse model of cardiac hypertrophy and the induced cardiac dysfunction. In cultured cardiac fibroblasts there is a direct of effect of BB on TGF-b and collagen I.