ABSTRACT
Aim To investigate whether the effect of Aβ25-35 on Bcl-2 and Bax gene transcription through DNA methylation in SH-SY5Y cell.Methods Differ-ent concentrations of Aβ25-35 (0, 25, 50 μmol? L-1 ) were treated with SH-SY5Y cells for 48 h or 72 h in vitro.The optimal concentration and time of Aβ25-35 in-duced SH-SY5 Y apoptosis were determined by MTT method.Protein expression levels of Bcl-2 and Bax of Aβ25-35-treated groups were determined by Western blot.Real time PCR was used to detect the mRNA lev-els of DNA methyltransferase including DNMT 1 , DN-MT3a, DMT3b, MeCP2. Methylation specific PCR ( MSP) was used to analyze the effect of Aβ25-35 media-ted Bcl-2 and Bax gene promoter methylation .Results 25 μmol? L-1 Aβ25-35 was exposed to SH-SY5Y cells for 72 h, MTT assay showed that cell viability was (68.49 ±9.83 )%, which was significantly reduced compared with the control group ( P 0.05 ); MSP results showed that Bcl-2 and Bax unmethylated ampli-fication was positive , methylated amplification was neg-ative in control group , Bcl-2 and Bax unmethylated amplification was positive and methylated amplification was negative in Aβ25-35-treated group.Conclusion DNA methylation of Bcl-2 and Bax gene promoter are not affected during Aβ25-35 induced SH-SY5Y cell ap-optosis .