In Vitro and In Vivo Inhibition of Intestinal Glucose Transport by Guava (Psidium Guajava) Extracts.

Ulrike Müller,Julian Weghuber,Nicole Ollinger,Georg Sandner,Bettina Schwarzinger,Peter Lanzerstorfer,Otmar Höglinger,Verena Stadlbauer,Marcus Iken,Tobias Kühne,Markus Himmelsbach,Clemens Schwarzinger,Flora Stübl

doi:10.1002/mnfr.201701012

Abstract

ScopeKnown pharmacological activities of guava (Psidium guajava) include modulation of blood glucose levels. However, mechanistic details remain unclear in many cases.Methods and resultsThis study investigated the effects of different guava leaf and fruit extracts on intestinal glucose transport in vitro and on postprandial glucose levels in vivo. Substantial dose‐ and time‐dependent glucose transport inhibition (up to 80%) was observed for both guava fruit and leaf extracts, at conceivable physiological concentrations in Caco‐2 cells. Using sodium‐containing (both glucose transporters, sodium‐dependent glucose transporter 1 [SGLT1] and glucose transporter 2 [GLUT2], are active) and sodium‐free (only GLUT2 is active) conditions, we show that inhibition of GLUT2 was greater than that of SGLT1. Inhibitory properties of guava extracts also remained stable after digestive juice treatment, indicating a good chemical stability of the active substances. Furthermore, we could unequivocally show that guava extracts significantly reduced blood glucose levels (≈fourfold reduction) in a time‐dependent manner in vivo (C57BL/6N mice). Extracts were characterized with respect to their main putative bioactive compounds (polyphenols) using HPLC and LC‐MS.ConclusionThe data demonstrated that guava leaf and fruit extracts can potentially contribute to the regulation of blood glucose levels.

Highlights

Introduction tioninhibited or delayed intestinal glucose absorption may have a tremendous impact on managing diabetes and Diabetes mellitus is a chronic disease that leads to hy- obesity.perglycemia
The data demonstrated that guava leaf and fruit extracts can cose transporter 4 (GLUT4) activities.[4,5]
Antihyperglycemic properties of guava extracts, via reducing the postprandial glucose response, were proved in vivo (C57BL/6N mice). These results indicate that consumption of guava extracts may contribute to moderate regulation of blood glucose levels by direct inhibition of intestinal glucose transport

Summary

Introduction

Inhibited or delayed intestinal glucose absorption may have a tremendous impact on managing diabetes and Diabetes mellitus is a chronic disease that leads to hy- obesity. In this context, people with type 2 diabetes mellitus. Intestinal glucose absorption is predominantly facilitated by (T2DM) constitute the majority of people (>90%) with diabetes sodium-dependent glucose transporter 1 (SGLT1),[8,9] whereas.

Results

Discussion

Conclusion