Oxidative stress is initiated by reactive oxygen species, the primary factor in many chronic diseases. Moringa oleifera possesses strong antioxidant properties due to the presence of various phytochemicals. In this study, we investigated the effect of M. oleifera leaf extract on markers of oxidative stress in HL60 cells exposed to oxidative stress. HL60 cells were incubated with different concentrations of M. oleifera leaf extract, and cells were harvested for viability assays on days 1, 2, and 3. Antioxidant indexes (malondialdehyde, reduced glutathione, superoxide dismutase, and catalase) were measured on days 1, 2, and 3. Supplementation with the moringa leaf extract at all concentrations resulted in significant reductions in lipid peroxidation in cells that were or were not incubated in an environment with excess oxidative stress. The most significant reduction in this parameter occurred after 24 h of incubation. The results show that reductions seen in this parameter may be due to the modulation of the endogenous antioxidant defense system by extract supplementation. Cell viability was also improved in cells incubated in moringa leaf extract at concentrations of 800 and 1000 μg/mL. This finding, however, did not corroborate with lipid peroxidation results at 1000 μg/mL extract supplementation. Further investigations are needed to clarify the underlying mechanism responsible for increased cell viability at this concentration. We can, therefore, conclude that the moringa leaf extract offered added protection from oxidative stress within the first 24 h, as well as increasing cell viability at certain concentrations.
Keywords: HL60; Moringa oleifera; antioxidant; antiproliferative; catalase; glutathione.