Cucurbita argyrosperma Seed Extract Ameliorating Oxidative Stress in H9c2 Cardiomyocytes through Suppression of Intracellular Reactive Oxygen Species Production

Background: Oxidative stress induced by the excessive reactive oxygen species (ROS) generation is involved in the pathogenesis of various diseases. Methanol extract from Cucurbita argyrosperma (CM) was used to test for antioxidant and antioxidative stress. Materials and Methods: The radical scavenging potential was determined using eight different in vitro assays: 1,1‑diphenyl‑2‑picrylhydrazyl (DPPH), 2,2’‑Azino‑bis‑3‑ethylbenzothiazoline‑6‑sulfonic acid (ABTS) radical, β‑carotene‑linoleic acid, chelating activity, ferric reducing antioxidant power (FRAP), hydroxyl radical, nitric oxide (NO) radical, and superoxide anion radicals, palmitate (PA) on H9c2 cells, and H2O2‑induced cell damage on H9c2 cardiomyocytes. Results: CM showed antioxidant activity with DPPH radical values of EC50 7.6 ± 5.38 mg/mL, β‑carotene‑linoleic acid EC50 of 279.4 ± 36.32 mg/ml, chelating activity EC50 of 301.2 ± 9.78 mg/ml, FRAP EC50 of 101.3 ± 3.10 mg/ml, hydroxyl EC50 of 42.6 ± 8.6 mg/mL, superoxide EC50 of 50.6 ± 8.66 mg/ml, NO EC50 of 101.2 ± 19.74 mg/ml, and ABTS EC50 of 13.2 ± 4.9 mg/ml. The methanol extract preincubation decreases the intracellular ROS induced by H2O2 and PA in H9c2 cells in a concentration‑dependent manner. The methanol extract could also protect H9c2 cells and inhibit the activity of xanthine oxidase, malondialdehyde, and lactate dehydrogenase which increases cell viability, heme oxygenase‑1, glutathione/oxidized glutathione, superoxide dismutase‑1, catalase, and GSH‑Px? levels. Conclusions: The finding suggests that methanol extract can protect the oxidative stress‑induced cardiomyocyte damage through ROS regulation and can be used as a therapeutic agent for the improvement of oxidative stress in various diseases.