Effects of smoking on the methylation of promoter region of ERα in men with coronay artery disease

Epigenetic modifications, especially alteration in DNA methylation, are increasingly being recognized as a key factor in the pathogenesis of complex disorders, including atherosclerosis. However, there are limited data on the epigenetic changes in the coronary artery disease (CAD) patients. In the present study we evaluated the effect of smoking as aepigenetic factor on the methylation of promoter region of the estrogen receptor alpha (ERα) gene in men withcoronary artery disease. 46 men with CAD and 46 healthy men were participated in the current study. Both groupsof case and controls divided by 23 smoker and 23 non-smoker subjects. Genomic DNA were extracted from peripheral lymphocytes and treated with bisulphite for modification. Methylation status was evaluated by methylation specific-PCR (MS-PCR). There were no significant difference in methylatin status of promotor region ofERα gene between patients with CAD and control groups (p=0.494). When the subjects with and without smoking werecompared according to DNA methylation status, the methylation percentage in the smoker and non-smoker groupswere as follow: the homozygote methylated subjects, 13.4% and 0.0%, heterozygote individual, 87.26% and 43.47% and the homozygote non-methylated subjects, 8.69% and 56.5%, respectively. There was a significant difference between smoker and non-smoker subjects according to methylation status of promoter region of ERα gene. In conclusion, smoking with reduction the expression of ER α by methylation the promoter region of the gene can probably have a key role in the occurrence of CAD in men

Keywords:

coronary artery disease , DNA methylation , ERα , smoking