title: Triclosan reduces the levels of global DNA methylation in HepG2 cells.
abstract: Triclosan (TCS), an antibacterial agent, is widely used in a variety of personal care and industrial products. TCS is associated with the development of liver tumors in rodents and has become a concern to environmental and human health. This study is aimed at investigating whether TCS could modulate the levels of global DNA methylation (GDM) in human hepatocytes. We found that treatment with different doses (1.25-10 μM) of TCS did not affect HepG2 cell viability, but significantly reduced the levels of GDM in HepG2 cells, and inhibited DNMT1 activity. Furthermore, treatment with TCS significantly inhibited the methylated DNA-binding domain 2 (MBD2), MBD3, and MeCP2 mRNA transcription. In addition, treatment with TCS promoted the accumulation of 8-hydroxy-2-deoxyguanosine (8-OHdG) in a dose-dependent manner, which was abrogated by treatment with an antioxidant, N-acetylcysteine (NAC). Collectively, our data indicated that TCS reduced the levels of GDM and down-regulated the MBD2, MBD3, and MeCP2 gene expression by increasing 8-OHdG levels and inhibiting the DNMT1 activity in HepG2 cells.
authors.affiliation: State Key Laboratory of Organic Geochemistry, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China. mahuimin@gig.ac.cn
authors.forename: Huimin
authors.initials: H
authors.lastname: Ma
authors.forename: Liujin
authors.initials: L
authors.lastname: Zheng
authors.forename: Yuhua
authors.initials: Y
authors.lastname: Li
authors.forename: Shangxia
authors.initials: S
authors.lastname: Pan
authors.forename: Junjie
authors.initials: J
authors.lastname: Hu
authors.forename: Zhiqiang
authors.initials: Z
authors.lastname: Yu
authors.forename: Gan
authors.initials: G
authors.lastname: Zhang
authors.forename: Guoying
authors.initials: G
authors.lastname: Sheng
authors.forename: Jiamo
authors.initials: J
authors.lastname: Fu
mesh_terms: D000080242:8-Hydroxy-2'-Deoxyguanosine; D000891:Anti-Infective Agents, Local / Q000494:pharmacology*; D004247:DNA / Q000235:genetics / Q000378:metabolism; D000076123:DNA (Cytosine-5-)-Methyltransferase 1; D004248:DNA (Cytosine-5-)-Methyltransferases / Q000037:antagonists & inhibitors / Q000378:metabolism; D019175:DNA Methylation / Q000187:drug effects*; D004268:DNA-Binding Proteins / Q000235:genetics; D003849:Deoxyguanosine / Q000031:analogs & derivatives / Q000378:metabolism; D015536:Down-Regulation / Q000187:drug effects; D056945:Hep G2 Cells / Q000187:drug effects* / Q000378:metabolism; D006801:Humans; D051783:Methyl-CpG-Binding Protein 2 / Q000235:genetics; D014260:Triclosan / Q000494:pharmacology*
chemical_list: D000891:Anti-Infective Agents, Local; D004268:DNA-Binding Proteins; C115368:MBD2 protein; C115369:MBD3 protein, human; D051783:Methyl-CpG-Binding Protein 2; D014260:Triclosan; D000080242:8-Hydroxy-2'-Deoxyguanosine; D004247:DNA; D000076123:DNA (Cytosine-5-)-Methyltransferase 1; D004248:DNA (Cytosine-5-)-Methyltransferases; C000619380:DNMT1 protein, human; D003849:Deoxyguanosine