title: Effect on morphology, oxidative stress and energy metabolism enzymes in the testes of mice after a 13-week oral administration of melamine and cyanuric acid combination.
abstract: Cases of pet poisoning and infant renal calculus have attracted much attention to the toxicity of melamine and its derivatives, such as cyanuric acid. Although individually melamine and cyanuric acid have low toxicity, their simultaneous presence can cause severe damage. Little is known about their adverse effects on the reproductive system. In this study, mice were orally administrated 1, 5 or 25 mg/kg/d of both melamine and cyanuric acid for 13 weeks. Lethargy, rough hair, and reduction of food and water intake and of body and testis weight were found after exposure to the combination, and pathological changes were found in the morphology of the testes, such as disruption of the seminiferous tubule structure, decrease of the spermatogenic cell series and coagulation necrosis. Total antioxidant capacity and superoxide dismutase activities and glutathione concentration was lower and malondialdehyde concentration was higher than in control mice. The activities of malate dehydrogenase, lactate dehydrogenase and Na(+)/K(+)-ATPase were also lower in combination treated mice than in control mice. These results indicate that the combined exposure to both melamine and cyanuric acid damaged testes in mice by either a direct or indirect effect, which may be related to renal failure and secondary anorexia. Oxidative stress and lower energy production levels both contributed to the testicular damage.
authors.affiliation: College of Veterinary Medicine, Nanjing Agricultural University, Weigang 1, Nanjing 210095, China. lyj@njau.edu.cn
authors.forename: Yingjun
authors.initials: Y
authors.lastname: Lv
authors.forename: Zhijun
authors.initials: Z
authors.lastname: Liu
authors.forename: Yujie
authors.initials: Y
authors.lastname: Tian
authors.forename: Hongbo
authors.initials: H
authors.lastname: Chen
mesh_terms: D000818:Animals; D001835:Body Weight / Q000187:drug effects; D004326:Drinking / Q000187:drug effects; D004338:Drug Combinations; D004734:Energy Metabolism / Q000187:drug effects* / Q000502:physiology; D005978:Glutathione / Q000378:metabolism; D007770:L-Lactate Dehydrogenase / Q000378:metabolism; D008291:Malate Dehydrogenase / Q000378:metabolism; D008297:Male; D008315:Malondialdehyde / Q000378:metabolism; D051379:Mice; D008813:Mice, Inbred ICR; D009929:Organ Size / Q000187:drug effects; D018384:Oxidative Stress / Q000187:drug effects*; D012117:Resins, Synthetic / Q000633:toxicity*; D000254:Sodium-Potassium-Exchanging ATPase / Q000378:metabolism; D013482:Superoxide Dismutase / Q000378:metabolism; D013737:Testis / Q000187:drug effects* / Q000201:enzymology; D018675:Toxicity Tests; D014227:Triazines / Q000633:toxicity*
chemical_list: D004338:Drug Combinations; D012117:Resins, Synthetic; D014227:Triazines; D008315:Malondialdehyde; D007770:L-Lactate Dehydrogenase; D008291:Malate Dehydrogenase; D013482:Superoxide Dismutase; D000254:Sodium-Potassium-Exchanging ATPase; D005978:Glutathione; C004632:cyanuric acid; C011907:melamine