title: [Genotoxic effects of oral-exposed TiO2 nanoparticles on bone marrow cells in young rats].
abstract: OBJECTIVE
  To explore the genotoxic effects of oral-exposed TiO2 nanoparticles on bone marrow cells in young rats.
  
  
  METHODS
  Twenty-eight SD male young rats (4 weeks old) were randomly divided into 4 groups, which were exposed to TiO2 nanoparticles ((75 ± 15) nm, anatase) through intragastric administration at 0, 10, 50 and 200 mg/kg body weight (bw) every day for 30 days. The bone marrow cells were collected for micronuclei and γ-H2AX immunofluorescence analysis.
  
  
  RESULTS
  The percentage of γ-H2AX foci-positive cells (37.4 ± 10.0)% in the 50 mg/kg bw dose group were significantly higher than that in the control group (19.8 ± 3.1)% (t value was -17.59, P < 0.01). No significantly difference was found in polychromatic erythrocyte/normochromatic erythrocyte (PCE/NCE) ratio and PCE micronucleus rate between three experimental groups and control group.
  
  
  CONCLUSIONS
  TiO2 nanoparticles can increase the frequency of DNA double-strand breaks in bone marrow cells, but has no effect on micronucleus of bone marrow cells in young rats.
authors.affiliation: Department of Occupational and Environmental Health Sciences, School of Public Health, Peking University Health Science Center, Beijing 100191, China.
authors.forename: Yun
authors.initials: Y
authors.lastname: Wang
authors.affiliation: Department of Occupational and Environmental Health Sciences, School of Public Health, Peking University Health Science Center, Beijing 100191, China.
authors.forename: Zhangjian
authors.initials: Z
authors.lastname: Chen
authors.affiliation: Department of Occupational and Environmental Health Sciences, School of Public Health, Peking University Health Science Center, Beijing 100191, China.
authors.forename: Te
authors.initials: T
authors.lastname: Ba
authors.affiliation: Department of Occupational and Environmental Health Sciences, School of Public Health, Peking University Health Science Center, Beijing 100191, China.
authors.forename: Ji
authors.initials: J
authors.lastname: Pu
authors.affiliation: Department of Occupational and Environmental Health Sciences, School of Public Health, Peking University Health Science Center, Beijing 100191, China.
authors.forename: Yongen
authors.initials: Y
authors.lastname: Gu
authors.affiliation: Department of Occupational and Environmental Health Sciences, School of Public Health, Peking University Health Science Center, Beijing 100191, China.
authors.forename: Jian
authors.initials: J
authors.lastname: Guo
authors.affiliation: Department of Occupational and Environmental Health Sciences, School of Public Health, Peking University Health Science Center, Beijing 100191, China. Email:jiaguangjia@bjmu.edu.cn.
authors.forename: Guang
authors.initials: G
authors.lastname: Jia
mesh_terms: D000818:Animals; D001854:Bone Marrow Cells; D004249:DNA Damage; D006657:Histones; D008297:Male; D048629:Micronuclei, Chromosome-Defective; D053758:Nanoparticles; D051381:Rats; D014025:Titanium
chemical_list: C468783:H2AX protein, human; D006657:Histones; C009495:titanium dioxide; D014025:Titanium