2.1. Study Design and Participants
chronic non-communicable diseases, amenorrhea
VASODILATION, CARDIOVASCULAR DISEASES
A randomized trial conducted on 48 individuals compared the effects of resveratrol supplementation (500 mg/day) and energy restriction (1000 kcal/day) for 30 days on SIRT1 and vascular reactivity parameters. The study participants were 24 postmenopausal women (01 years of natural amenorrhea) and 24 men aged 55 to 65, all without previous cardiovascular diseases. Participants were healthy volunteers without chronic non-communicable diseases, normal physical examination, and normal resting electrocardiogram. After a washout period of 15 days without using any medications or supplements, the participants were randomly assigned to either caloric restriction or resveratrol groups in a 1:1 ratio according to sex. Subsequently, participants underwent a standardized interview, blood sample collection, anthropometric assessment, blood pressure and heart rate measurement, and vascular reactivity test. Such procedures were repeated at the end of the study.Exclusion criteria were: BMI ≥ 30 kg/mThe analyzed clinical variables were age, weight, body mass index (BMI), waist circumference, blood pressure, and heart rate. Biochemical parameters included serum concentrations of triglycerides, total cholesterol, high-density lipoprotein cholesterol (HDL-c), low-density lipoprotein cholesterol (LDL-c), apolipoprotein A–I (apoA–I), apolipoprotein B (apoB), lipoprotein (a) (Lp(a)), non-esterified fatty acids (NEFA), glucose, insulin, high-sensitivity C-reactive protein (hsCRP), noradrenaline (NA), and serum levels and gene expression of SIRT1. Vascular reactivity parameters included endothelium-dependent and endothelium-independent vasodilation.The energy restriction group consisted of a low-calorie diet (1000 kcal/day), corresponding to an approximate 50% energy intake reduction. Food diaries were used to analyze the adherence to the proposed interventions. Subjects were instructed to write down all the food intake daily and not exceed 1000 kcal/day. Participants included in the resveratrol group were instructed to take resveratrol capsules (250 mg of resveratrol each) twice a day (The study was approved by the Ethics Committee of the University of São Paulo Medical School Hospital (CAAE:00788012.8.0000.0068), and all participants signed informed consent. Trial registration: 