Effect of statins on sirtuin 1 and endothelial nitric oxide synthase expression in young patients with a history of premature myocardial infarction

OBJECTIVE
The present study was an investigation of the effect of statins on the expression of circulating sirtuin 1 (SIRT1) and endothelial nitric oxide synthase (eNOS) proteins, and on the distribution of single nucleotide polymorphisms (SNPs) of the SIRT1 gene in patients with a history of premature myocardial infarction (PMI).

METHODS
A total of 108 patients who had suffered from a premature ST-elevation myocardial infarction (STEMI) under the age of 45 years were enrolled in this study. While 79 patients had been taking statins since the index event, 29 patients had not been treated with statins post myocardial infarction (MI) or the therapy had been withdrawn at the 4-week follow-up control. The control group consisted of 91 healthy patients without a previous cardiovascular event. The levels of SIRT1 and eNOS protein; oxidative stress markers, like total antioxidant status (TAS), total oxidant status (TOS), and the oxidative stress index (OSI); as well as the distribution of the SNPs rs7069102 and rs2273773 were measured and analyzed.

RESULTS
A significant increase in the SIRT1 level (p<0.001) and a significant decrease in the eNOS level (p=0.001) was observed in all genotypes and alleles for both SNPs in patients who received statin therapy compared with the control group. Both SNPs were distributed in a similar frequency in the 2 MI groups, irrespective of statin treatment.

CONCLUSION
Statins induce SIRT1 protein, which might have a cardioprotective role after PMI. In addition, the eNOS protein level was low in all of the MI patients, suggesting that impairment of eNOS expression is disease-specific without a causal link to SIRT1.