Serum concentrations and gene expression of sirtuin 1 in healthy and slightly overweight subjects after caloric restriction or resveratrol supplementation: A randomized trial

Background: Sirtuin 1 (Sirt1) plays an important role in vascular biology, and influences aspects of age-dependent atherosclerosis. In animals, the sirtuin system is strongly influenced by resveratrol and caloric restriction, but its expression in humans is controversial. This study investigated the effects of resveratrol and caloric restriction on Sirt1 serum concentrations and vascular biomarkers in a healthy human population. Methods and results: Forty-eight healthy participants (24 women) aged 55-65 years were randomized to either 30 days of resveratrol administration (500 mg/day) or caloric restriction (1000 cal/day). Blood was collected at baseline and day 30. Laboratory data analyzed were triglycerides, total cholesterol, HDL, VLDL, LDL, apolipoprotein A1, apolipoprotein B, lipoprotein (a), non-esterified fatty acids (NEFA), glucose, insulin, oxidative stress, C-reactive protein, and Sirt1. Expression of the Sirt1 gene was analyzed using real-time PCR. Caloric restriction diminished the abdominal circumference and improved the lipid profile, but not resveratrol intervention. Resveratrol and caloric restriction increased serum concentrations of Sirt1, from 1.06 +/- 0.71 to 5.75 +/- 2.98 ng/mL; p < 0.0001, and from 1.65 +/- 1.81 to 5.80 +/- 2.23 ng/mL; p < 0.0001, respectively. Sirt1 increased in women and men in both interventions. On the other hand expression of Sirt1 mRNA was not different after caloric restriction and resveratrol treatment. Conclusions: Caloric restriction and resveratrol significantly increased plasma concentrations of Sirt1. The longterm impact of these interventions on atherosclerosis should be assessed. (C) 2016 Elsevier Ireland Ltd. All rights reserved.