[Enhancement effect of polychlorinated biphenyl on benzo (a) pyrene-induced DNA damage in HepG2 cells].
OBJECTIVE
To study the effect of polychlorinated biphenyl, Aroclor1254 on benzo (a) pyrene [B (a) P]-induced DNA damage in HepG2 cells.


METHODS
HepG2 cells were pretreated with Aroclor1254 (11.5, 23 and 46 micromol/L) for 24 hours and then exposed to B (a) P (50 micromol/L). DMSO (10 ml/L) was used as solvent control. Single cell gel electrophoresis (SCGE) and high-performance liquid chromatography-electrochemical detection (HPLC-EC) assays were applied to detect DNA single-strand breaks and 8-hydroxy-2'-deoxyguanosine (8-OHdG) in HepG2 cells, respectively.


RESULTS
Average Oliver tail moment (OTM) and 8-OHdG level in HepG2 cells were significantly increased in B (a) P treated group (1.66 +/- 0.21), (23.31 +/- 6.02) 8-OHdG/10(6)dG than that in solvent control (0.79 +/- 0.15), (12.31 +/- 3.24) 8-OHdG/10(6)dG, respectively. In Aroclor 1254 treated group (11.5, 23.0, 46.0 micromol/L), average OTM were 0.88 +/- 0.20, 1.01 +/- 0.15 and 1.10 +/- 0.16, and 8-OHdG levels were (19.57 +/- 7.57), (22.80 +/- 9.16) and (31.74 +/- 9.25) 8-OHdG/10(6)dG, respectively. A concentration of 46 micromol/L Aroclor1254 caused a significant increase of 8-OHdG level as compared with the solvent control. After pretreatment of HepG2 cells with Aroclor1254 (11.5, 23.0 and 46.0 micromol/L), B (a) P induced more DNA strand breaks (OTM: 2.14 +/- 0.22, 2.43 +/- 0.32 and 2.71 +/- 0.31) and 8-OHdG [(32.50 +/- 3.81), (49.23 +/- 16.66) and (60.36 +/- 18.04) 8-OHdG/10(6)dG] in HepG2 cells than B (a) P alone.


CONCLUSIONS
Aroclor1254 might enhance B (a) P-induced DNA damage in HepG2 cells, which should imply a synergistic effect of Aroclor1254 on the genotoxicity of B (a) P.
Zou
Ya-ling
YL
Department of Occupational and Environmental Health, School of Public Health, Tongji Medical College of Huazhong University of Science and Technology, Wuhan 430030, China.
Lai
Rui-ping
RP
Zhou
Li-hong
LH
Li
Xiao-yan
XY
Lu
Wen-qing
WQ
D001564:Benzo(a)pyrene / Q000633:toxicity*; D045744:Cell Line, Tumor; D004249:DNA Damage / Q000187:drug effects*; D004357:Drug Synergism; D006801:Humans; D011078:Polychlorinated Biphenyls / Q000633:toxicity*
D001564:Benzo(a)pyrene; D011078:Polychlorinated Biphenyls