Relationship between polymerase eta expression and DNA damage-tolerance in human hepatic cells by hydroquinone.
- Author:
Gong-hua HU
1
;
Zhi-xiong ZHUANG
;
Hai-yan HUANG
;
Lei YU
;
Lin-qing YANG
;
Wei-dong JI
Author Information
- Publication Type:Journal Article
- MeSH: Cell Survival; drug effects; Cells, Cultured; DNA Damage; drug effects; DNA Repair; DNA-Directed DNA Polymerase; metabolism; Hepatocytes; drug effects; metabolism; Humans; Hydroquinones; adverse effects; Mutagens
- From: Chinese Journal of Preventive Medicine 2009;43(1):56-60
- CountryChina
- Language:Chinese
-
Abstract:
OBJECTIVETo investigate the effects of hydroquinone (HQ) on expression of Polymerase eta (Pol eta) and DNA damage in human hepatic cells (L-02), and to explore the role and possible mechanism of Pol eta involved in the process of DNA damage-tolerance.
METHODSAfter L-02 hepatic cells were exposed to HQ with various concentrations (0, 5, 10, 20, 40, 80 and 160 micromol/L) for 24 h, cell survival rate was detected by MTT assay; DNA impairment was detected by single cell gel electrophoresis (SCGE); Real-time fluorescent quantitative PCR and Western blotting methods were used to measure the expression of Pol eta at the mRNA and protein level in L-02 hepatic cells exposed to HQ with various concentrations (0, 5, 10, 20, 40, 80 and 160 micromol/L).
RESULTSMTT assay showed that HQ with concentrations from 0 to 80 micromol/L had little effect on the survival rate of L-02 (P>0.05); whereas the survival rate of the group of 160 micromol/Lwas significantly higher than that of the control (P<0.01) after being treated with HQ for 24 h; the higher dose of HQ presented, the more degrees of DNA damage were produced. It was found that HQ in a low concentration (1-80 micromol/L) could induce the expression of Pol eta which was in proportion to the increasements of HQ concentration; the expression levels of mRNA and protein were reached to the maximum when treated with 80 micromol/L; the expression of Pol eta decreased (the relative quantity values were 2.32 +/- 0.16 and 1.20 respectively) once the concentration of HQ exceeded 160 micromol/L as compared with the group of 80 micromol/L, but it was higher than that of the control.
CONCLUSIONThis study suggested that Pol eta might involve in the process of DNA damage-tolerance induced by HQ in the hepatic cells.