Olive oil is the major component of the Mediterranean diet and has rich history of nutritional and medicinal uses. In the present study, the antidepressant and anxiolytic effects and their neurochemical basis following repeated administration of extravirgin olive oil were monitored. Male albino Wistar rats were used during study. Animals of test group were given olive oil orally at the dose of 0.25？mL/kg daily for 4 weeks. Control rats received equal volume of water. Elevated-plus maze (EPM) test and forced swim test (FST) were performed for the assessment of anxiety and depression like symptoms. An increase in time spent in open arm in EPM and increased struggling time in FST following long-term administration of olive oil indicate that olive oil has anxiolytic and antidepressant properties. Neurochemical results showed that repeated administration of olive oil decreased the levels of brain 5-HT (5-hydroxytryptamine), 5-HIAA (5-hydroxyindoleacetic acid), and levels of DA (dopamine); however, levels of DA metabolite HVA (homovalinic acid) were increased. Hence, present findings suggest that olive oil has neuroprotective effects. It reduces behavioral deficits via altering 5-HT and DA metabolism. So it could be used as a therapeutic substance for the treatment of depression and anxiety. 1. Introduction Olive (Olea europaea) is in the family Oleaceae that is used throughout the world especially in the Mediterranean region. It is full of nutrients and vitamins. Extravirgin olive oil is derived from the first pressing of the olives. It has the most delicate flavor and antioxidant benefits [1]. Olive oil is rich in monounsaturated fatty acids (MUFAs) and has excellent health benefits [2]. Olive oil is composed mainly of mixed triglyceride esters of oleic acid, palmitic acid, and other fatty acids, along with the traces of squalene (up to 0.7%) and sterols (about 0.2%; phytosterol & tocosterols). It also contains group of antioxidants that are esters of tyrosol and hydroxytyrosols, including oleocanthal, oleuropein, vitamin E, and carotenoids. Oleuropein is a chemical that prevents the oxidation of LDL (low density lipoproteins) particles [3]. Evidence from epidemiological studies suggests that a higher proportion of monounsaturated fats in the diet are linked with a reduction in the risk of coronary heart disease [4]. It has been reported that olive oil consumption has favorable effects on cholesterol regulation and LDL cholesterol oxidation and it also exerts antiplatelet [5], anti-inflammatory, antithrombotic, and antihypertensive as well as vasodilatory
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