Metabolic Response to Mulberry Extract Supplementation in Patients With Diabetic Nephropathy: a Randomized Controlled Trial

Abstract

Introduction. This study aimed to evaluate the effects of mulberry extract administration on markers of insulin metabolism, lipid concentrations, and biomarkers of inflammation and oxidative stress in patients with diabetic nephropathy (DN).

Materials and Methods. Sixty patients were randomly allocated into 2 groups to receive either 300 mg/d of mulberry extract (n = 30) or placebo (n = 30), twice per day for 12 weeks. Fasting blood samples were taken at the onset of the study and 12 weeks after supplementation to examine markers of insulin metabolism, lipid concentrations, and biomarkers of inflammation and oxidative stress.

Results. Mulberry extract, compared to placebo, resulted in significant reductions in serum triglycerides (-37.3 ± 64.7 mg/dL versus +3.0 ± 78.8 mg/dL, P = .03) and very low-density lipoprotein cholesterol (-7.4 ± 12.9 mg/dL versus +0.6 ± 15.8 mg/dL, P = .03), and a significant increase in high-density lipoprotein cholesterol concentration (+0.5 ± 4.0 mg/dL versus -2.0 ± 5.0 mg/dL, P = .03). Other significant changes were in serum high-sensitivity C-reaction protein (-2.3 ± 4.5 µg/mL versus -0.1 ± 2.2 µg/mL, P = .02), plasma glutathione (+87.8 ± 159.7 µmol/L versus -24.2 ± 138.8 µmol/L, P = .005) and malondialdehyde (-0.03 ± 0.5 µmol/L versus +0.7 ± 1.0 µmol/L, P < .001).  

Conclusions. These findings showed that mulberry extract administration had favorable effects on serum lipids, HSCRP, glutathione, and malondialdehyde levels in DN patients; however, it did not affect markers of insulin metabolism or biomarkers of inflammation and oxidative stress.