title: [Protective Effect of S-isopentenyl-L-cysteine against DNA Damage in Irradiated Mice].
abstract: OBJECTIVE
  To evaluate the protective effect of S-isopentenyl-L-cysteine,a new cysteine derivative,on DNA damage induced by radiation by using acute radiation injury animal models.
  
  
  METHODS
  Forty ICR mice were randomly divided into five groups:the control group,1.0Gy gamma irradiation group,1.0Gy gamma irradiation combined with S-isopentenyl-L-cysteine group,7.2Gy gamma irradiation group,and 7.2Gy gamma irradiation combined with S-isopentenyl-L-cysteine group,with 8 mice in each group.The comet assay and bone marrow polychromatic micronucleus experiments were performed to evaluate the double-strand DNA breaks in ICR mice exposed to 1.0 and 7.2Gy gamma-ray, respectively.
  
  
  RESULTS
  The tail DNA percentage,tail length,tail moment,and olive tail moment of peripheral blood lymphocytes in 7.2Gy gamma irradiation group were significantly higher than that of the control group (P<0.01).And it was also observed that above experimental indexes of 7.2Gy gamma irradiation combined with S-isopentenyl-L-cysteine group was significantly less than that of 7.2Gy gamma irradiation group (P<0.05). In addition,the micronucleus rate of 1.0Gy gamma irradiation group and 7.2Gy gamma irradiation group were both significantly higher than in the control group (P<0.01). In addition,in mice given S-isopentenyl-L-cysteine before irradiation,the micronucleus rate of ICR mice exposed to 1.0 and 7.2Gy gamma-ray decreased from (39.5000 ± 3.3141)‰ to (28.1667±4.1345)‰ (P=0.033) and from (76.5000 ± 4.6242)‰ to (22.8333 ± 3.6553)‰(P=0.000),respectively. The bone marrow polychromatic micronucleus experiment indicated that the value of polychromatic erythrocyte (PCE)/normochromatic erythrocyte(NCE) of ICR mice exposed to 1.0 and 7.2Gy gamma-ray was less than the control group(P<0.05). Meanwhile,after irradiating by certain dose,the value of PCE/NCE in mice given S-isopentenyl-L-cysteine before irradiation was significantly higher than the corresponding groups (P<0.05).
  
  
  CONCLUSIONS
  S-isopentenyl-L-cysteine has a good protective effect against DNA damage induced by radiation.
authors.affiliation: Tianjin Key Laboratory of Radiation Medicine and Molecular Nuclear Medicine,Institute of Radiation Medicine,CAMS and PUMC,Tianjin 300192,China.
authors.forename: Qi-sheng
authors.initials: QS
authors.lastname: Zheng
authors.affiliation: Tianjin Key Laboratory of Radiation Medicine and Molecular Nuclear Medicine,Institute of Radiation Medicine,CAMS and PUMC,Tianjin 300192,China.
authors.forename: Guang-yun
authors.initials: GY
authors.lastname: Yu
authors.affiliation: Tianjin Key Laboratory of Radiation Medicine and Molecular Nuclear Medicine,Institute of Radiation Medicine,CAMS and PUMC,Tianjin 300192,China.
authors.forename: Xin
authors.initials: X
authors.lastname: He
authors.affiliation: Tianjin Key Laboratory of Radiation Medicine and Molecular Nuclear Medicine,Institute of Radiation Medicine,CAMS and PUMC,Tianjin 300192,China.
authors.forename: Ming
authors.initials: M
authors.lastname: Jiang
authors.affiliation: Tianjin Key Laboratory of Radiation Medicine and Molecular Nuclear Medicine,Institute of Radiation Medicine,CAMS and PUMC,Tianjin 300192,China.
authors.forename: Xiao-fei
authors.initials: XF
authors.lastname: Chu
authors.affiliation: Tianjin Key Laboratory of Radiation Medicine and Molecular Nuclear Medicine,Institute of Radiation Medicine,CAMS and PUMC,Tianjin 300192,China.
authors.forename: Shu-yi
authors.initials: SY
authors.lastname: Zhao
authors.affiliation: Tianjin Key Laboratory of Radiation Medicine and Molecular Nuclear Medicine,Institute of Radiation Medicine,CAMS and PUMC,Tianjin 300192,China.
authors.forename: Sai-jun
authors.initials: SJ
authors.lastname: Fan
authors.affiliation: Tianjin Key Laboratory of Radiation Medicine and Molecular Nuclear Medicine,Institute of Radiation Medicine,CAMS and PUMC,Tianjin 300192,China.
authors.forename: Pei-xun
authors.initials: PX
authors.lastname: Liu
mesh_terms: D000818:Animals; D001853:Bone Marrow; D003545:Cysteine; D004249:DNA Damage; D004195:Disease Models, Animal; D005720:Gamma Rays; D051379:Mice; D008813:Mice, Inbred ICR; D011832:Radiation Injuries; D011837:Radiation-Protective Agents
chemical_list: D011837:Radiation-Protective Agents; D003545:Cysteine