Ursolic acid of Origanum majorana L. reduces Abeta-induced oxidative injury.

Amyloid beta protein (Abeta) increases free radical production and lipid peroxidation in PC12 nerve cells, leading to apoptosis and cell death. The effect of ursolic acid from Origanum majorana L. on Abeta-induced neurotoxicity was investigated using PC12 cells. Pretreatment with isolated ursolic acid and vitamin E prevented the PC12 cell from reactive oxygen species (ROS) toxicity that is mediated by Abeta. The ursolic acid resulted in decreased Abeta toxicity assessed by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT), lactate dehydrogenase (LDH), and trypan blue assay. Thus, treatment with these antioxidants inhibited the Abeta-induced neurotoxic effect. Therefore, these results indicate that micromolar Abeta-induced oxidative cell death is reduced by ursolic acid from Origanum majorana L.