Unveiling the Differential Anti-Oxidant Activity of Maslinic Acid in Murine Melanoma Cells and in Rat Embryonic Healthy Cells Following Treatment With Hydrogen Peroxide

Maslinic acid (MA) is a natural triterpene from Olea europaea whose pharmacological functions have been showed. The objective of this study was to examine MA effect on cell viability (by MTT assay), reactive oxygen species (ROS levels, by flow cytometry) and key anti-oxidant enzyme activities (by spectrophotometry) in murine skin melanoma (B16F10) cells compared to healthy cells (A10). MA induced cytotoxic effects in cancer cells (IC50 42 µM) whereas no effect was found in A10 cells treated with MA (up to 210 µM). In order to produce a stress situation in cells, 0.15 mM of H2O2 were added. Under stressful conditions, MA protected both cell lines against oxidative damage, decreasing intracellular ROS, being higher in B16F10 than in A10 cells. The treatment with H2O2 and without MA produced different responses in anti-oxidant enzymes activities depending on cell line. In A10 cells, all enzymes were up-regulated, but in B16F10 cells only superoxide dismutase, glutathione S-transferase and glutathione peroxidase increased their activities. MA restored the enzyme activities to similar levels than control group in both cell lines, highlighting that in A10 cells the highest MA doses induced values lower than control. Overall, these findings demonstrate the great anti-oxidant capacity of MA.