title: Sublethal effects of zinc oxide nanoparticles on male reproductive cells.
abstract: Environmental exposure to nanomaterials is inevitable as nanomaterials become part of our daily life, and as a result, nanotoxicity research is gaining attention. Most investigators focused on the effects of zinc oxide nanoparticles (ZnO NPs) on human health, while limited information was available on the male reproductive system. Herein, mouse Sertoli cell line (TM-4) and spermatocyte cell line (GC2-spd) were used as in vitro models to explore the reproductive effects of ZnO NPs at sublethal dose and its underlying mechanisms. Cells were treated with different concentrations of ZnO NPs. By cell viability assay, a dose of 8μg/mL was found as a sublethal dose and increased the ROS levels in both cells. The decreased glutathione level and increased MDA level were also found in ZnO NPs treated group. In TM4 cells, the expressions of BTB proteins (ZO-1, occludin, claudin-5, and connexin-43) were lower in the ZnO NPs group. The increased cell permeability and increased TNF-α secretion were also observed in ZnO NPs group. In GC2-spd cells, S phase arrest and DNA damage occurred in ZnO NPs group, which could be partially rescued by NAC. Our findings demonstrated that exposure to ZnO NPs induced ROS generation, caused DNA damage of germ cells, and down-regulated the expression of BTB proteins in Sertoli cells which could compromise the integrity of the blood-testis barrier. All these contributed to the male reproductive cytotoxic effects of ZnO NPs that could be partially rescued by anti-oxidants.
authors.affiliation: State Key Laboratory of Reproductive Medicine, Institute of Toxicology, Nanjing Medical University, Nanjing 211166, China; Key Laboratory of Modern Toxicology of Ministry of Education, School of Public Health, Nanjing Medical University, Nanjing 211166, China.
authors.forename: Qian
authors.initials: Q
authors.lastname: Liu
authors.affiliation: State Key Laboratory of Reproductive Medicine, Institute of Toxicology, Nanjing Medical University, Nanjing 211166, China; Key Laboratory of Modern Toxicology of Ministry of Education, School of Public Health, Nanjing Medical University, Nanjing 211166, China.
authors.forename: Cheng
authors.initials: C
authors.lastname: Xu
authors.affiliation: Nanjing Institute of Environmental Sciences, Key Laboratory of Pesticide Environmental Assessment and Pollution Control, Ministry of Environmental Protection, Nanjing 210042, China.
authors.forename: Guixiang
authors.initials: G
authors.lastname: Ji
authors.affiliation: State Key Laboratory of Reproductive Medicine, Institute of Toxicology, Nanjing Medical University, Nanjing 211166, China; Key Laboratory of Modern Toxicology of Ministry of Education, School of Public Health, Nanjing Medical University, Nanjing 211166, China.
authors.forename: Hui
authors.initials: H
authors.lastname: Liu
authors.affiliation: Department of Environmental and Occupational Health Sciences, School of Public Health and Information Sciences, University of Louisville, Louisville, KY 40202, USA.
authors.forename: Yiqun
authors.initials: Y
authors.lastname: Mo
authors.affiliation: Department of Environmental and Occupational Health Sciences, School of Public Health and Information Sciences, University of Louisville, Louisville, KY 40202, USA.
authors.forename: David J
authors.initials: DJ
authors.lastname: Tollerud
authors.affiliation: State Key Laboratory of Reproductive Medicine, Institute of Toxicology, Nanjing Medical University, Nanjing 211166, China; Key Laboratory of Modern Toxicology of Ministry of Education, School of Public Health, Nanjing Medical University, Nanjing 211166, China. Electronic address: aihuagu@njmu.edu.cn.
authors.forename: Aihua
authors.initials: A
authors.lastname: Gu
authors.affiliation: Department of Environmental and Occupational Health Sciences, School of Public Health and Information Sciences, University of Louisville, Louisville, KY 40202, USA. Electronic address: qunwei.zhang@louisville.edu.
authors.forename: Qunwei
authors.initials: Q
authors.lastname: Zhang
mesh_terms: D000818:Animals; D002460:Cell Line; D002470:Cell Survival / Q000187:drug effects; D004249:DNA Damage; D005978:Glutathione / Q000378:metabolism; D008297:Male; D008315:Malondialdehyde / Q000378:metabolism; D008565:Membrane Proteins / Q000378:metabolism; D053768:Metal Nanoparticles / Q000633:toxicity*; D051379:Mice; D017382:Reactive Oxygen Species / Q000378:metabolism; D012708:Sertoli Cells / Q000187:drug effects* / Q000378:metabolism; D013090:Spermatocytes / Q000187:drug effects* / Q000378:metabolism; D014409:Tumor Necrosis Factor-alpha / Q000378:metabolism; D015034:Zinc Oxide / Q000633:toxicity*
chemical_list: D008565:Membrane Proteins; D017382:Reactive Oxygen Species; D014409:Tumor Necrosis Factor-alpha; D008315:Malondialdehyde; D005978:Glutathione; D015034:Zinc Oxide
keywords: In vitro; Male reproductive cells; Reactive oxygen species; The blood-testis barrier (BTB); Zinc oxide nanoparticles