ABSTRACT
OBJECTIVE: To investigate the effect of bisphenol A exposure on the expression of DNA methyltransferase(Dnmt) gene in mouse Leydig cell line TM3 cells. METHODS: TM3 cells were randomly divided into 0, 20, 50, 125 and 300 μmol/L dose group(0 μmol/L dose group was the control group). Cells were treated with various concentration of bisphenol A solution for 24 hours.The viability of TM3 cells was determined by CCK-8 method, and the mRNA expression of Dnmt1, Dnmt3 a and Dnmt3 b was detected by real-time fluorescence quantitative polymerase chain reaction. RESULTS:The viability of TM3 cells decreased with the increasing doses of bisphenol A(P<0.01). The relative mRNA expression of Dnmt1 in TM3 cells decreased with the increase of doses of bisphenol A(P<0.01).The relative mRNA expression of Dnmt3 b in TM3 cells in the 20, 50, 125, 300 μmol/L dose group was lower than that in the control group(P<0.05).There was no statistical significant difference in the relative mRNA expression of Dnmt3 a in TM3 cells in these 5 groups(P>0.05). CONCLUSION: Bisphenol exposure is cytotoxic to TM3 cells. This toxic effect may be related to changes in Dnmt mRNA expression.