Premature Myocardial Infarction: Genetic Variations in SIRT1 Affect Disease Susceptibility

OBJECTIVES: Premature myocardial infarction (PMI) is an uncommon disease, and its incidence varies between 2% and 10%, rising, depending on genetic susceptibility under the influence of lifestyle. The purpose of this study was to investigate the association between SIRT1 single nucleotide polymorphisms (SNPs), SIRT1, and eNOS (endothelial nitric oxide synthase) protein expressions, total antioxidant status (TAS), total oxidant status (TOS), and oxidative stress index (OSI) in young patients with premature ST-elevation myocardial infarction (STEMI). METHODS: Genotyping of the three single-nucleotide polymorphisms (rs7895833 A > G in the promoter region, rs7069102 C > G in intron 4, and rs2273773 C > T in exon 5) in SIRT1 gene was performed in 108 consecutive patients (87.0% were men with a mean age of 40.74 ± 3.82 years) suffering from ST-elevation myocardial infarction at the age of ≤45 and 91 control subjects. RESULTS: The risk for myocardial infarction was increased by 2.31 times in carriers of CC or CG genotypes. SIRT1 protein levels were enhanced and endothelial nitric oxide synthase levels were diminished in ST-elevation myocardial infarction patients regardless of the underlying gene variant. There was no correlation between SIRT1 expression and the amount of endothelial nitric oxide synthase, total antioxidant status, total oxidant status, and oxidative stress index levels in patients and in the control group either. CONCLUSIONS: SIRT1 single-nucleotide polymorphisms were associated with premature myocardial infarction, which affected the SIRT1 and endothelial nitric oxide synthase protein expression, irrespective of the underlying SIRT1 genotype.