Changes in Presenilin 1 gene methylation pattern in diet-induced B vitamin deficiency

Aim of present study was to analyze the methylation pattern of PSEN1 promoter in SK-N-BE neuroblastoma cells and TgCRND8 mice, in a B vitamin (folate, B12 and B6) deficiency paradigm. PSEN1 methylation status has been evaluated through bisulphite modification and genomic sequencing. We demonstrate that B vitamin deficiency induces hypomethylation of specific CpG moieties in the 5′-flanking region; S-adenosylmethionine has been supplemented as methyl donor to reverse this effect. PSEN1 promoter methylation status is correlated with gene expression. These findings pinpoint a direct relationship between B vitamin-dependent alteration of homocysteine cycle and DNA methylation and also indicate that PSEN1 promoter is regulated by methylation of specific CpG moieties.