Open Journal of Medicinal Chemistry, 2012, 2, 119-128 doi:10.4236/ojmc.2012.24015 Published Online December 2012 (http://www.SciRP.org/journal/ojmc) Inhibitory Effect of Aqueous Extract of Moringa oleifera and Newbuoldia laevis Leaves on Ferrous Sulphate and Sodium Nitroprusside Induced Oxidative Stress in Rat’s Testes in Vitro* Seun F. Akomolafe 1,2# , Ganiyu Oboh 2 , Afolabi A. Akindahunsi 2 , Ayodele J. Akinyemi 2,3 , Olusola Adeyanju 4 1 Department of Biochemistry, Ekiti State University, Ado Ekiti, Nigeria 2 Department of Biochemistry, Federal University of Technology, Akure, Nigeria 3 Department of Biochemistry, Afe Babalola University, Ado Ekiti, Nigeria 4 Department of Chemistry, University of Jos, Jos, Nigeria Email: # purposefulseun@yahoo.co.uk Received October 10, 2012; revised November 15, 2012; accepted November 26, 2012 ABSTRACT Oxidative stress has been identified as one of the factors that affects fertility status. Therefore, this study sought to in- vestigate the inhibitory effect of aqueous extract of Moringa oleifera and Newbuoldia laevis leaves on FeSO 4 and So- dium Nitroprusside (SNP) induced lipid peroxidation in rat testes in vitro. Incubation of the testes tissue homogenate in the presence of FeSO 4 and SNP caused a significant increase in the malondialdehyde (MDA) contents of the testes. The aqueous extract from both Moringa oleifera and Newbuoldia laevis leaves caused a significant decrease in the MDA contents of the testes in a dose-dependent manner. However, aqueous extract from Moringa oleifera leaf (EC 50 = 0.29 mg/ml) had a significant (P < 0.05) higher inhibitory effect on Fe 2+ induced lipid peroxidation in the rat testes homoge- nate than that of Newbuoldia laevis leaf extract (EC 50 = 0.58 mg/ml); while there was no significant (P < 0.05) differ- ence between the plant extracts on SNP induced lipid peroxidation in the rat testes homogenates. Therefore, part of the mechanisms through which the water extractable phytochemicals in the leaves protect the testes from oxidative stress may be through their antioxidant activity; DPPH scavenging ability, Fe 2+ chelating and reducing power. Therefore, these plants have potential to prevent oxidative stress in testes and improve fertility outcomes. Keywords: Lipid Peroxidation; Malondialdehyde; Antioxidant Activity; Testes 1. Introduction Infertility is a major clinical problem, affecting people medically and psychosocially. Published literature data indicates that 15% of all couples in the United States are infertile, and the male factor is responsible for 25% of these cases [1]. In many cases the cause of male infertil- ity, oxidative stress (OS) has been identified as one of the major factors that affects fertility status and thus, has been extensively studied in recent years. Spermatozoa, like any other aerobic cell, are constantly facing the “oxy- gen-paradox” [2]. Oxygen is essential to sustain life as physiological levels of reactive oxygen species (ROS) are necessary to maintain normal cell function [3]. Con- versely, breakdown products of oxygen such as ROS can be detrimental to cell function and survival [4]. Reactive oxygen species are present as free radicals. Examples of ROS include the hydroxyl superoxide radical, hydrogen peroxide, peroxyl radical, and hypochlorite ion. These are the common forms of ROS that have been considered injurious to sperm survival and function when present in abundance. Although iron is necessary physiologically as compo- nents of many enzymes and proteins, free iron in the cy- tosol and mitochondria could cause considerable oxida- tive damage by acting catalytically in the production of ROS which have the potential to damage cellular lipids, nucleic acids, proteins and carbohydrate resulting in wide ranging impairment in cellular function and integrity [5]. The mechanism by which iron can cause this deleterious effect is that Fe (II) can react with hydrogen peroxide (H 2 O 2 ) to produce the hydroxyl radical (OH) via the Fenton reaction, whereas superoxide can react with iron (III) to regenerate iron (II) that can participate in the Fenton reaction [6]. The overproduction of ROS can lead * No competing financial interests exist. # Corresponding author. Copyright © 2012 SciRes. OJMC