In recent years, interest in the use of nutraceuticals has risen substantially. Olive oil has been shown to produce a number of therapeutically important effects due to its antioxidant property. The present study concerns neurochemical and behavioral effects of long term administration of low and high doses (0.1 mL/kg and 0.25 mL/kg) of olive oil and associated antioxidant effects in rats. Long term administration of low dose of olive oil increased motor activity in an open field, decreased anxiety in elevated plus maze test, and enhanced memory in Morris water maze test. Whole brain levels of serotonin increased with low dose of olive oil while homovanillic acid (HVA), a metabolite of dopamine increased with both doses of olive oil. Low dose of olive oil increased glutathione peroxidase activity whereas high dose of olive oil decreased malondialdehyde levels in plasma. The results show that particularly low doses of olive oil reduce anxiety and improve learning and memory together with antioxidant properties, brain dopamine and serotonin also play important role in the therapeutically important effects of olive oil.
M. Atif Raza Cheema, Khalid Mahmood and Darakhshan J Haleem