title: The Effect of Nano-Titanium Dioxide on Limb Bud Development of NMRI Mouse Embryo In Vivo.
abstract: OBJECTIVE
  There is a wide application of titanium dioxide (TiO2) nanoparticles (NPs) in industry. These particles are used in various products, and they also has biological effects on cells and organs through direct contact.
  
  
  METHODS
  In this experimental research, the effect of TiO2 on chondrogenesis of forelimb buds of mice embryos was assessed in in vivo condition. Concentrations of 30, 150 and 500 mg/kg body weight (BW) TiO2 NPs (20 nm size) dissolved in distilled water were injected intraperitoneally to Naval Medical Research Institute (NMRI) mice on day 11.5 of gestation. On day 15, limb buds were amputated from the embryos and skeletogeneis of limb buds were studied.
  
  
  RESULTS
  TiO2 NPs caused the significant changes in chondrocytes in the following developmental stages: resting, proliferating, hypertrophy, degenerating, perichondrium and mesenchymal cells. Decreased number of mesenchymal cells and increased level of chondrocytes were observed after the injection of different concentrations of TiO2, which proves the unpredictable effects of TiO2 on limb buds.
  
  
  CONCLUSIONS
  Results of the present study showed TiO2 NPs accelerated the chondrogenesis of limb buds, but further studies are recommended to predict TiO2 toxicity effects on organogenesis.
authors.affiliation: Department of Biology, Faculty of Science, Islamic Azad University, Science and Research Branch, Tehran, Iran.
authors.forename: Kazem
authors.initials: K
authors.lastname: Parivar
authors.affiliation: Department of Biology, Faculty of Science, Islamic Azad University, Science and Research Branch, Tehran, Iran.
authors.forename: Nasim
authors.initials: N
authors.lastname: Hayati Rudbari
authors.affiliation: Department of Biology, Faculty of Science, Islamic Azad University, Ghaemshahr, Mazandaran, Iran.
authors.forename: Ramazan
authors.initials: R
authors.lastname: Khanbabaee
authors.affiliation: Department of Biology, Faculty of Science, Islamic Azad University, Ghaemshahr, Mazandaran, Iran.
authors.forename: Mahya
authors.initials: M
authors.lastname: Khaleghi
keywords: Chondrogenesis; Limb Bud; Nanoparticles; Titanium Dioxide