Oat β-glucan depresses SGLT1- and GLUT2-mediated glucose transport in intestinal epithelial cells (IEC-6).

Abstract

Oat β-glucan consumption is linked to reduced risk factors associated with diabetes and obesity by lowering glycemic response and serum level of low-density lipoproteins. The purpose of this study was to identify the mechanism of action of oat β-glucan at the interface between the gut wall and the lumen responsible for attenuating glucose levels. We proposed that viscous oat β-glucan acts as a physical barrier to glucose uptake in normally absorptive gut epithelial cells IEC-6 by affecting the expression of intestinal glucose transporters. Concentration and time-dependent changes in glucose uptake were established by using a nonmetabolizable glucose analog 2-[N-(7-nitrobenz-2-oxa-1,3-diazol-4-yl)amino]-2-deoxy-d-glucose. The effectiveness of nutrient transport in IEC-6 cells was shown by significant differences in glucose uptake and corresponding transporter expression. The expressions of glucose transporters sodium-glucose-linked transport protein 1 (SGLT1) and glucose transporter 2 (GLUT2) increased with time (0-60 minutes) and glucose levels (5-25 mmol/L). The suppression of glucose uptake and SGLT1 and GLUT2 expression by increasing concentrations (4-8 mg/mL) of oat β-glucan demonstrated a direct effect of the physical properties of oat β-glucan on glucose transport. These results affirmed oat β-glucan as a dietary agent for minimizing postprandial glucose and showed that modulating the activity of the key intestinal glucose transporters with oat β-glucan could be an effective way of lowering blood glucose levels in patients with diabetes.

• Authors: Nazanin N Abbasi, Peter P Purslow, Susan M Tosh, Marica Bakovic
• Journal: Nutrition research (New York, N.Y.) (Nutr Res) Vol. 36 Issue 6 Pg. 541-52 (06 2016) ISSN: 1879-0739 [Electronic] United States
• PMID: 27188900 (Publication Type: Journal Article)
• Copyright: Copyright © 2016 Elsevier Inc. All rights reserved.

Chemical References

• Actins
• Glucose Transporter Type 2
• RNA, Messenger
• Slc2a2 protein, rat
• Slc5a1 protein, rat
• Sodium-Glucose Transporter 1
• beta-Glucans
• beta-glucan, (1-3)(1-4)-
• Glucose

Topics

• Actins (genetics, metabolism)
• Animals
• Biological Transport (drug effects)
• Cell Survival (drug effects)
• Cells, Cultured
• Epithelial Cells (drug effects, metabolism)
• Glucose (metabolism)
• Glucose Transporter Type 2 (genetics, metabolism)
• Intestinal Mucosa (metabolism)
• Intestines (cytology, drug effects)
• Postprandial Period (drug effects)
• RNA, Messenger (genetics, metabolism)
• Rats
• Sodium-Glucose Transporter 1 (genetics, metabolism)
• beta-Glucans (analysis, pharmacology)