title: Cytotoxic effects of ZnO nanoparticles on mouse testicular cells.
abstract: BACKGROUND
  Nanoscience and nanotechnology are developing rapidly, and the applications of nanoparticles (NPs) have been found in several fields. At present, NPs are widely used in traditional consumer and industrial products, however, the properties and safety of NPs are still unclear and there are concerns about their potential environmental and health effects. The aim of the present study was to investigate the potential toxicity of ZnO NPs on testicular cells using both in vitro and in vivo systems in a mouse experimental model.
  
  
  METHODS
  ZnO NPs with a crystalline size of 70 nm were characterized with various analytical techniques, including ultraviolet-visible spectroscopy, Fourier transform infrared spectroscopy, X-ray diffraction, transmission electron microscopy, and atomic force microscopy. The cytotoxicity of the ZnO NPs was examined in vitro on Leydig cell and Sertoli cell lines, and in vivo on the testes of CD1 mice injected with single doses of ZnO NPs.
  
  
  RESULTS
  ZnO NPs were internalized by Leydig cells and Sertoli cells, and this resulted in cytotoxicity in a time- and dose-dependent manner through the induction of apoptosis. Apoptosis likely occurred as a consequence of DNA damage (detected as γ-H2AX and RAD51 foci) caused by increase in reactive oxygen species associated with loss of mitochondrial membrane potential. In addition, injection of ZnO NPs in male mice caused structural alterations in the seminiferous epithelium and sperm abnormalities.
  
  
  CONCLUSIONS
  These results demonstrate that ZnO NPs have the potential to induce apoptosis in testicular cells likely through DNA damage caused by reactive oxygen species, with possible adverse consequences for spermatogenesis and therefore, male fertility. This suggests that evaluating the potential impacts of engineered NPs is essential prior to their mass production, to address both the environmental and human health concerns and also to develop sustainable and safer nanomaterials.
authors: College of Biological and Pharmaceutical Engineering, Wuhan Polytechnic University, Wuhan, People's Republic of China.
authors: Zhe
authors: Z
authors: Han
authors: College of Biological and Pharmaceutical Engineering, Wuhan Polytechnic University, Wuhan, People's Republic of China.
authors: Qi
authors: Q
authors: Yan
authors: Key Laboratory of Animal Reproduction and Germplasm Enhancement in Universities of Shandong, College of Animal Science and Technology, Qingdao Agricultural University, Qingdao, People's Republic of China.
authors: Wei
authors: W
authors: Ge
authors: College of Biological and Pharmaceutical Engineering, Wuhan Polytechnic University, Wuhan, People's Republic of China.
authors: Zhi-Guo
authors: ZG
authors: Liu
authors: Department of Stem Cell and Regenerative Biology, Konkuk University, Seoul, Republic of Korea.
authors: Sangiliyandi
authors: S
authors: Gurunathan
authors: Department of Biomedicine and Prevention, University of Rome "Tor Vergata", Rome, Italy.
authors: Massimo
authors: M
authors: De Felici
authors: Key Laboratory of Animal Reproduction and Germplasm Enhancement in Universities of Shandong, College of Animal Science and Technology, Qingdao Agricultural University, Qingdao, People's Republic of China.
authors: Wei
authors: W
authors: Shen
authors: College of Biological and Pharmaceutical Engineering, Wuhan Polytechnic University, Wuhan, People's Republic of China.
authors: Xi-Feng
authors: XF
authors: Zhang
mesh_terms: D000818:Animals; D017209:Apoptosis / Q000187:drug effects*; D002478:Cells, Cultured; D004249:DNA Damage / Q000187:drug effects; D006801:Humans; D007985:Leydig Cells / Q000187:drug effects / Q000473:pathology*; D008297:Male; D053768:Metal Nanoparticles / Q000737:chemistry / Q000633:toxicity*; D051379:Mice; D018625:Microscopy, Atomic Force; D046529:Microscopy, Electron, Transmission; D036103:Nanotechnology; D017382:Reactive Oxygen Species / Q000378:metabolism; D012708:Sertoli Cells / Q000187:drug effects / Q000473:pathology*; D017550:Spectroscopy, Fourier Transform Infrared; D014961:X-Ray Diffraction; D015034:Zinc Oxide / Q000737:chemistry / Q000633:toxicity*
chemical_list: D017382:Reactive Oxygen Species; D015034:Zinc Oxide
keywords: Leydig cells; Sertoli cells; ZnO nanoparticle; mice