Cardioprotective effect of green tea and green coffee extract as metformin’s add-on to prevent cardiac fibrosis in a rat model of metabolic syndrome

Metabolic syndrome (METS) is a cluster of risk factors contributing to cardiovascular disease (CVD) development. Agonist-related hypertension and obesity may occur due to excess cardiac pressure caused by increased systemic blood pressure. In addition, METS also enhances the progression of cardiac remodelling through several cardiac fibrosis-related genes. METS treatment is managed using metformin as a glycemic control agent, often given with other complementary agents. This study investigates the effect of green tea and green coffee extract therapy as an add-on to metformin in preventing cardiac organ dysfunction and overexpression of cardiac fibrosis biomarkers in the METS rat model. METS model rats were divided into five groups. The rats' blood pressure, flow, and volume are measured using a non-invasive tail-cuff sphygmomanometer. After nine weeks of treatment, the heart was isolated for measurement of angiotensinogen receptor 1 (ATR1), transforming growth factor β (TGFβ), and collagen type 1 (COL1A1) gene expression by reverse-transcriptase PCR. This study found that there was a significant improvement in blood pressure, increased tail blood flow, and volume (p-value<0.05) and decreased ATR1, TGFβ, and COL1A1 gene expression (p-value=0.000) in the green tea-green coffee and metformin (COMB) therapy group. The correlation analysis results show a positive linear relationship between SBP, DBP, TBF, AT1R, TGFβ, and COL1A1. This study found that green tea and green coffee extract therapy as an add-on to metformin could prevent cardiac dysfunction by improving blood pressure, flow and volume, reducing overexpression of ATR1, TGFβ, COL1A1 gene expression that is related to cardiac fibrosis in the METS rat model.