title: Beta-cypermethrin impairs reproductive function in male mice by inducing oxidative stress.
abstract: Cypermethrin (CYP), an insecticide, has deleterious effects on male reproductive function. The objective was to identify whether the effects of beta-CYP on male reproductive organs were associated with oxidative stress. Three doses of beta-CYP (1, 10, and 20mg/kg) were administered to male mice for 35 d, with or without vitamin E (20mg/kg). The moderate (10mg/kg) and high (20mg/kg) doses of beta-CYP not only decreased body weight and the weight of the testes, epididymides, seminal vesicles, and prostate (P<0.05) but also reduced serum testosterone concentration and the expression of steroidogenic acute regulatory protein (P<0.05), in addition to damaging the seminiferous tubules and sperm development. Furthermore, moderate and high doses of beta-CYP administration decreased sperm number, sperm motility, and intact acrosome rate (P<0.05). Based on ultrastructural analyses, high doses of beta-CYP produced swelling and degeneration of mitochondria and the smooth endoplasmic reticulum of Leydig cells and caused the formation of concentric circles. These toxic effects of beta-CYP may be mediated by increasing oxidative stress, as the moderate and high doses of this compound increased malondialdehyde and nitric oxide in testes (P<0.05); reduced the activity of catalase, glutathione peroxidase (GSH-Px), and superoxide dismutase (P<0.05); and activated ERK1/2 (P<0.05). Vitamin E reversed the effects of beta-CYP on testosterone production and testis damage (P<0.05 vs. the high-dose group). Therefore, we inferred that beta-CYP damaged the structure of testes and decreased sperm output by inducing oxidative stress.
authors.affiliation: Chongqing Key Laboratory of Forage & Herbivore, College of Animal Science and Technology, Southwest University, Chongqing 400716, China.
authors.forename: X-Z
authors.initials: XZ
authors.lastname: Wang
authors.forename: S-S
authors.initials: SS
authors.lastname: Liu
authors.forename: Y
authors.initials: Y
authors.lastname: Sun
authors.forename: J-Y
authors.initials: JY
authors.lastname: Wu
authors.forename: Y-L
authors.initials: YL
authors.lastname: Zhou
authors.forename: J-H
authors.initials: JH
authors.lastname: Zhang
mesh_terms: D000818:Animals; D021461:Animals, Outbred Strains; D004822:Epididymis / Q000033:anatomy & histology / Q000187:drug effects / Q000378:metabolism; D007306:Insecticides / Q000633:toxicity; D007985:Leydig Cells / Q000166:cytology / Q000187:drug effects / Q000648:ultrastructure; D015227:Lipid Peroxidation / Q000187:drug effects; D008297:Male; D051379:Mice; D009929:Organ Size / Q000187:drug effects; D018384:Oxidative Stress / Q000187:drug effects*; D011722:Pyrethrins / Q000633:toxicity*; D017382:Reactive Oxygen Species / Q000378:metabolism; D012098:Reproduction / Q000187:drug effects* / Q000502:physiology; D013094:Spermatozoa / Q000187:drug effects / Q000378:metabolism; D013737:Testis / Q000033:anatomy & histology / Q000187:drug effects / Q000378:metabolism; D013739:Testosterone / Q000097:blood; D015854:Up-Regulation / Q000187:drug effects
chemical_list: D007306:Insecticides; D011722:Pyrethrins; D017382:Reactive Oxygen Species; C017160:cypermethrin; D013739:Testosterone