Effects of Berberis aristata/Silybum marianum association on metabolic parameters and adipocytokines in overweight dyslipidemic patients

Nutraceuticals and functional foods have attracted considerable interest as potential alternative therapies for treatment of different cardiovascular disorders and insulin resistance. We evaluated the efficacy of a combination of Berberis Aristata/Silybum Marianum extract (Berberol®) in a sample of overweight, dyslipidemic patients at low cardiovascular risk. We enrolled 105 Caucasian, euglycemic, overweight, dyslipidemic patients, of either sex. At baseline all patients underwent a 6 months run-in period during which they followed an adequate diet and practiced physical activity. At the end of the run-in period, patients were randomised to take placebo or a combination of Berberis aristata/Silybum marianum, 1 tablet during the lunch and 1 tablet during the dinner, for three months, in a double-blind, placebo-controlled design. Berberis aristata/Silybum marianum and placebo were then interrupted for 2 months (wash-out period), and all patients continued with only diet and physical activity. At the end of the wash-out period, patients re-started Berberis aristata/Silybum marianum or placebo twice a day for further 3 months. We evaluated during the run-in period, at randomisation, before and after the wash-out period these parameters: body weight and BMI, fasting plasma glucose, lipid profile, insulin resistance, retinol binding protein-4 (RBP-4), adiponectin (ADN), resistin. Total cholesterol, LDL-C, and Tg decreased, and HDL-C increase after 3 months of Berberis aristata/Silybum marianum, both compared to baseline and placebo. Berberis aristata/Silybum marianum decreased fasting plasma insulin, and HOMA-IR, both compared to baseline and to placebo. Moreover, there was a decrease of RBP-4, and resistin, and an increase of ADN after 3 months of Berberis aristata/Silybum marianum. All these positive effects disappeared after the wash-out period, and re-appeared after the re-introduction of the drug. We observed a significant correlation between HOMA-index decrease and resistin, and RBP-4 decrease, and between HOMA-index decrease and ADN increase in Berberis aristata/Silybum marianum group, but not in placebo group. Berberis aristata/Silybum marianum fixed combination seems to be safe and effective in improving lipid profile, but also in improving insulin resistance and adipocytokines levels.