Effect of Ethanolic Extract of Vernonia amygdalina on the Proliferation, Viability and Function of Mouse Induced Pluripotent Stem Cells and Cardiomyocytes.

Vernonia amygdalina (V. amygdalina) leaves are commonly used in traditional medicine around the world for the treatment of a plethora disorders, including heart disease. The aim of this study was to examine and evaluate the cardiac effect of V. amygdalina leaf extracts using mouse induced pluripotent stem cells (miPSCs) and their cardiomyocytes' (CMs) derivatives. We used a well-established stem cell culture to assess the effect of V. amygdalina extract on miPSC proliferation, EB formation and the beating activity of miPS cell-derived CMs. To study the cytotoxic effect of our extract, undifferentiating miPSCs were exposed to different concentrations of V. amygdalina. Cell colony formation and EB morphology were assessed using microscopy, whereas the cell viability was accessed with an impedance-based method and immunocytochemistry following treatment with different concentrations of V. amygdalina. Ethanolic extract of V. amygdalina induced toxicity in miPSCs, as revealed by a decrease in cell proliferation and colony formation, and an increase in cell death at a concentration of ≥20 mg/mL. At a concentration of 10 mg/mL, the rate of beating EBs was observed with no significant difference regarding the yield of cardiac cells. In addition, V. amygdalina did not affect the sarcomeric organization, but induced positive or negative effects on miPS cell-derived CMs' differentiation in a concentration-dependent manner. Taken together, our findings demonstrate that the ethanolic extract of V. amygdalina affected cell proliferation, colony forming and cardiac beating capacities in a concentration-dependent manner.