Quercetin Attenuates Lambda Cyhalothrin- Induced Reproductive Toxicity in Male Rats Fatma Ben Abdallah, 1,2* Hamadi Fetoui, 3* Nassira Zribi, 1,2 Feiza Fakhfakh, 2 Leila Keskes 1,2 1 Laboratory of Histology Embryology and Reproductive Biology, Faculty of Medicine of Sfax, University of sfax, Tunisia 2 Laboratory of Molecular Human Genetics, Faculty of Medicine of Sfax, University of Sfax, Tunisia 3 Animal Physiology Laboratory, Life Science Department, Sciences Faculty of Sfax, University of Sfax, Tunisia Received 14 January 2011; revised 30 June 2011; accepted 10 July 2011 ABSTRACT: The aim of this study was to evaluate the possible protective effects of Quercetin (Qe) against oxidative stress induced by k cyhalothrin (LTC) in reproductive system. Thirty-two male rats were divided into four groups. First group was allocated as the control group. Second group was given a Qe alone while the third group received a LTC alone. Animals in the fourth group were given a Qe with LTC. Caudae epididymis was removed for sperm analysis. Lipid peroxidation (LPO), superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx), glutathione-S-transferase (GST), and reduced gluta- thione (GSH) were determined in the testis. Additionally, the different histopathologic changes were observed in the testis of animals. LTC exposure significantly increased the abnormal morphology and LPO. On the contrary, sperm motility, viability and count, levels of GSH, and activities of SOD, CAT, GPx, and GSTwere significantly decreased compared to controls. Qe with LTC offset the decrease in functional sperm parameters, antioxidants enzymatic activities, and nonenzymatic antioxidant levels when compared with LTC-treated rats. Furthermore, LTC showed irregular seminiferous tubules containing only Sertoli cells and Qe with LTC caused regular seminiferous tubules showing spermatogenesis at level of spermatocytes. We conclude that LTC-induced oxidative stress and functional sperm parameters in male rats, and dietary of Qe attenuates the reproductive toxicity of LTC to restore the antioxidant system and sperm parameters in male rats. # 2011 Wiley Periodicals, Inc. Environ Toxicol 00: 000–000, 2011. Keywords: lambda-cyhalothrin; Quercetin; reproductive system; antioxidants enzyme activities; histopathology of the testis INTRODUCTION The synthetic pyrethroids constitute a unique group of insecticides having pyrethrin-like structures with better per- formance characteristics and account for over 30% of insec- ticide use globally (Vijverberg and van den Bercken, 1982). These insecticides are analogs of naturally occurring pyrethrins and have been developed with the aim to improve the specificity and activity of natural insecticide pyrethrum (Sogorb and Vilanova, 2002). The favorable properties of this class of insecticides have promoted wide- spread application in virtually all sectors of food protection and pest control. With the use of pyrethroids steadily rising, there may be an urgent need to identify the adverse effects that may be associated with their use. It has been reported during pyrethroid metabolism, reactive oxygen species (ROS) were generated and caused oxidative stress in *These authors contributed equally to this work. Correspondence to: F. B. Abdallah; e-mail: fatma_isbs@yahoo.fr Published online in Wiley Online Library (wileyonlinelibrary.com). DOI 10.1002/tox.20762  C 2011 Wiley Periodicals, Inc. 1