DNA Methyltransferase Inhibitor 5-AZA-DC Regulates TGF1-Mediated Alteration of Neuroglial Cell Functions after Oxidative Stress.

5-AZA-DC is an efficient methylation inhibitor that inhibits methylation of target DNA. In this study, we explored the effects of 5-AZA-DC on the regulation of TGF1 on target genes in neuroglial cell, as well as neuroglial cell functions under oxidative stress. The oxidative stress was constructed by editing CRISPR/Cas9 for knock out Ang-1 and ApoE4 genes. Cells were subjected to TGF1 (or shTGF1) transfection and/or 5-AZA-DC intervention. Results showed that under oxidative stress, both TGF1 and shTGF1 transfection raised DNMT1, but reduced TGF1, PTEN, and TSC2 expressions in neuroglial cells. TGF1 directly bind to the promoter of PTEN gene. 5-AZA-DC intervention lowered DNMT1 and raised TGF1 expression, as well as promoted the binding between TGF1 and promoter of PTEN. TGF1 caused a significant increase in the DNA demethylation level of PTEN promoter, while 5-AZA-DC intervention reduced the DNA demethylation level of PTEN promoter. Under oxidative stress, TGF1 (or shTGF1) transfection inhibited neuroglial cell proliferation, migration, and invasion, promoted cell apoptosis. 5-AZA-DC intervention alleviated TGF1 (or shTGF1) transfection caused neuroglial cell proliferation, migration, and invasion inhibition, as well as cell apoptosis. To conclude, these results suggest that 5-AZA-DC can be used as a potential drug for epigenetic therapy on oxidative stress damage in neuroglial cells. The findings of this research provide theoretical basis and research ideas for methylation drug intervention and TGF1 gene as a possible precise target of glial oxidative stress diagnosis and treatment.