Impact of Opuntia ficus-indica Fruit Extracts on Toxicity Induced by Doxorubicin in Cardiomyocytes

Background and objectives: Doxorubicin is an antineoplastic agent whose administration may cause cardiotoxicity. Opuntia ficus-indica is a widely consumed cactus species with nutritional and antioxidant value. In this study, the effect of fruit extracts of Opuntia ficus-indica on doxorubicin-induced cardiotoxicity was investigated in vitro. Methods: Hydroalcoholic and anthocyanin-rich extracts were evaluated for total phenolic and anthocyanin contents. Pretreatment of H9C2 cardiomyocytes with both extracts (10-1000 µg/mL) and then exposure to doxorubicin (2 μM) for 24 h, and assessment of cell viability (MTT assay), intracellular reactive oxygen species (ROS) level, glutathione depletion, and total antioxidant capacity as ferric reducing antioxidant power (FRAP) were performed. Results: Incubation with the extracts (10-1000 µg/mL) for 24 h did not reduce the viability of cardiomyocytes. Pretreatment with hydroalcoholic extract (50-1000 μg/mL) and anthocyanin-rich extract (25-1000 μg/mL) significantly alleviated cytotoxicity from doxorubicin. Both extracts markedly reduced intracellular ROS levels, glutathione depletion, and elevated FRAP levels. However, anthocyanin-rich at 1000 μg/mL demonstrated a significantly greater effect in improving FRAP levels than hydroalcoholic extract. Conclusions: Findings of this in vitro study revealed the cytoprotective impact of hydroalcoholic and anthocyanin-rich extracts of O. ficus-indica fruits on doxorubicin-induced cardiotoxicity through antioxidative activities.