British Journal of Nutrition 2004-06-01

Quercetin glucosides inhibit glucose uptake into brush-border-membrane vesicles of porcine jejunum.

Rainer Cermak, Sandra Landgraf, Siegfried Wolffram

Index: Br. J. Nutr. 91(6) , 849-55, (2004)

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Abstract

Recent experimental data point to an interaction of dietary flavonol monoglucosides with the intestinal Na-dependent glucose transporter 1 (SGLT1). To investigate this interaction in more detail, we performed experiments with SGLT1-containing brush-border-membrane vesicles (BBMV) from pig jejunum. The flavonol quercetin-3-O-glucoside (Q3G) concentration-dependently inhibited Na-dependent uptake of radioactively labelled d-glucose into BBMV. Uptake of l-leucine was not inhibited by Q3G, indicating a specific interaction of the glucoside with SGLT1. Whereas the maximal transport rate of concentration-dependent initial glucose uptake was not altered in the presence of Q3G, the constant for half-maximal glucose uptake was increased, suggesting a competitive type of inhibition of glucose uptake by Q3G. Trans-stimulation experiments suggested the transport of Q3G via SGLT1. In addition, Q3G decreased the Na-independent diffusive uptake of glucose into BBMV. Other flavonoids were also tested for their inhibitory effect on d-glucose uptake. Among the tested quercetin glycosides, only the 4'-O-glucoside (Q4G) also inhibited Na-dependent glucose uptake into BBMV, whereas the 3-O-galactoside, the 3-O-glucorhamnoside and the aglycone quercetin itself were ineffective. Glucosides of some other flavonoid classes such as naringenin-7-O-glucoside, genistein-7-O-glucoside and cyanidin-3,5-O-diglucoside were ineffective as well. Thus, dietary quercetin monoglucosides, for example, Q3G and Q4G, have an impact on intestinal nutrient transporters such as SGLT1 and related systems.

Related Compounds

Structure Name/CAS No. Articles
spiraeoside Structure spiraeoside
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