The Metabolic Effects of Cynara Supplementation in Overweight and Obese Class I Subjects with Newly Detected Impaired Fasting Glycemia: A Double-Blind, Placebo-Controlled, Randomized Clinical Trial

Abstract

Impaired fasting glucose (IFG) is a condition that precedes diabetes and increases the risk of developing it. Studies support the hypoglycemic effect of Cynarascolymus (Cs) extracts due to the content of chlorogenic acid, which is a potent inhibitor of glucose 6-phosphate translocase and of dicaffeoylquinic acid derivatives that modulate the activity of alpha-glucosidase. Given this background, we investigated whether a new highly standardized Cs extract could improve glycemic control, insulin sensitivity and other metabolic parameters (total cholesterol (TC), low-density lipoprotein-cholesterol (LDL-C), high-density lipoprotein-cholesterol (HDL-C) Triglycerides, Apolipo protein B (ApoB), Apolipo protein A (ApoA), waist circumference, visceral adipose tissue (VAT) by dual-energy X-ray absorptiometry (DXA) in overweight subjects with newly diagnosed IFG. Fifty-four subjects (females/males 26/28, mean ± SD age 51.5 ± 6.2) were randomly assigned to the supplemented group (n = 27) and placebo (n = 27). After multiple testing correction, statistically significant interactions between time and group were observed for the primary endpoint glycemia (β = 0.36, p < 0.0001) and for the secondary endpoints HDL (β = −0.10, p < 0.0001), total cholesterol/HDL (β = 0.27, p < 0.0001), LDL (β = 0.15, p = 0.005), LDL/HDL (β = 0.23, p = 0.001), insulin (β = 1.28, p = 0.04), glycated hemoglobin (β = 0.21, p = 0.0002), A1c-derived average glucose (β = 0.34, p = 0.0002), ApoB (β = 6.00, p = 0.01), ApoA (β = −4.50, p = 0.04), ApoB/ApoA (β = 0.08, p = 0.003), waist circumference (β = 1.89, p = 0.05), VATβ = 222.37, p = 0.005). In conclusion, these results confirm that Cs supplementation has a significant effect on metabolic parameters in IFG patients.