Effect of Anthocyanins Supplementation on Serum IGFBP-4 Fragments and Glycemic Control in Patients with Fasting Hyperglycemia: A Randomized Controlled Trial

Diabetes Metab Syndr Obes. 2020 Sep 28;13:3395-3404. doi: 10.2147/DMSO.S266751. eCollection 2020.

Abstract

Background: Insulin-like growth factor binding protein-4 (IGFBP-4) fragments have been shown to be associated with cardiometabolic diseases. Anthocyanins as a subgroup of natural polyphenols could have benefits on treating cardiometabolic diseases. The aim of this study was to examine the effects of purified anthocyanins on serum IGFBP-4 fragments and glycemic control in patients with fasting hyperglycemia.

Methods: A set of 121 participants with elevated fasting glucose (≥5.6 mmol/L), who were originally randomly assigned to anthocyanins (320 mg/day) or placebo groups, were included in this study. Serum IGFBP-4 fragments, fasting and postload glucose, insulin, and C-peptide after a three-hour oral glucose tolerance test (OGTT) were measured at baseline and at the end of 12 weeks.

Results: Compared with placebo, anthocyanins increased serum IGFBP-4 fragments (net change 8.33 ng/mL, 95% CI [1.2, 15.47], p=0.023) and decreased fasting glucose (-0.4 mmol/L [-0.71, -0.1], p=0.01), 2-hour C-peptide (-1.02 ng/mL [-1.99, -0.04], p=0.041) and the 3-hour area under the curve (AUC) of C-peptide (-2.19 [-4.11, -0.27], p=0.026). No other significant difference in parameters for glycemic control and insulin resistance was observed.

Conclusion: Anthocyanins supplementation for 12 weeks improved serum IGFBP-4 fragments and decreased fasting glucose and postload C-peptide in patients with fasting hyperglycemia. Further studies are needed to confirm our findings and clarify the potential mechanism.

Trial registration: ClinicalTrials.gov, NCT02689765. Registered on 6 February 2016, https://clinicaltrials.gov/ct2/show/NCT02689765.

Keywords: C-peptide; IGFBP-4 fragments; anthocyanin; insulin resistance; oral glucose tolerance test.

Associated data

  • ClinicalTrials.gov/NCT02689765

Grant support

This study was supported by the Key Project of National Natural Science Foundation of China (grant number 81730090) and the Health Technology Project of NanShan, ShenZhen (grant number 2019034).