Effects of Rauwolfia Vomitoria extracts on monoamine oxidase activity in wistar rats

Abstract

Monoamine Oxidase (MAO; EC 1.4.3.4.) is a widely distributed mitochondrial enzyme with two isoforms: MAO-A and MAO-B. It has high expression levels in gastro-intestinal and hepatic as well as neuronal tissues. The enzyme catalyzes the oxidative deamination of a variety of monoamines, both endogenous and exogenous, and has major roles in metabolizing released neurotransmitters, and in detoxification of a large variety of endogenous and exogenous amines. Drugs which inhibit MAO are currently in clinical use for treatment of affective disorders. Major Depressive Disorder (MDD), the most prevalent mood disorder is the leading cause of worldwide disability. Core symptoms of MDD include depressed mood, irritability, anhedonia (defined as the reduced ability to experience pleasure from previously rewarding activities), difficulty concentrating, and disrupted appetite and sleep habits. Several clinical studies report a high prevalence of MDD comorbidity with inflammatory diseases including cardiovascular diseases, diabetes, metabolic disorders, asthma, and rheumatoid arthritis. Medicinal plant play a significant role in providing primary health care services to rural people serving as therapeutic agents as well as important raw materials for the manufacture of traditional and modern medicine. A large number of medicinal plants are claimed to possess the antidepressant properties in the traditional system and are also used extensively by people worldwide R. Vomitoria, a shrub of the family Apocynaceae is commonly called serpent wood or swizzler stick and is used locally in the treatment of mental disorders, nervous disorders and insomnia.The aim of this article is to review the findings of the studies on antidepressant effects, mechanism of action of medicinal plants with emphasis on monoamine oxidase enzyme. Ninety male Wistar rats were orally administered 125, 250 and 500 mg/kg body weight of aqueous and ethanol root extract of Rauwolfia vomitoria for 14 and 28 days. Animals were sacrificed by cervical dislocation and monoamine oxidase activity was determined spectrophotometrically. Rauwolfia vomitoria root decreased MAO significantly compared to standard imipramine, citalopram and control.