Moringa oleifera Hot Water Extract Protects Vero Cells from Hydrogen Peroxide-Induced Oxidative Stress by Regulating Mitochondria-Mediated Apoptotic Pathway and Nrf2/HO-1 Signaling.

The present study discloses the identification of phenolic compounds in Moringa oleifera hot water extract (MOH) and the evaluation of its antioxidant activity on H 2 O 2 -induced oxidative stress in Vero cells. Upon analysis, MOH was found to contain phenolic compounds and indicated 2,2-diphenyl-1-picrylhydrazyl (DPPH) and 2,2-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid) diammonium salt (ABTS + ) radical scavenging with IC 50 values of 102.52 and 122.55 µg/mL, respectively. The ferric reducing antioxidant power (FRAP) of MOH indicated a dose-dependent increase with a maximum absorbance at 125 μg/mL and the oxygen radical absorbance capacity (ORAC) of MOH was 1004.95 µmol TE/mg. Results showed that MOH dose-dependently reduced intracellular ROS generation in H 2 O 2 -stimulated Vero cells while increasing the cell viability. Fluorescence microscopy and flowcytometric analyses have supported the above findings. MOH markedly suppressed the H 2 O 2 -induced mitochondrial depolarization and apoptosis through suppression of the mitochondrial-mediated apoptosis pathway and activated the Nrf2/HO-1 signaling pathway by possibly involving H 2 O 2 generation in cell media. Findings of western blot were supported by immunocytochemistry of Nrf2 nuclear translocation. Thus, MOH bioactivity would potentiate its applications in manufacturing functional food.