Interaction of quercetin glucosides with the intestinal sodium/glucose co-transporter (SGLT-1).
Recently it has been postulated that flavonoid glucosides may be absorbed by the small intestine via the SGLT-1. Therefore, we applied an in vitro mucosal uptake method to investigate mucosal uptake of the non-metabolisable glucose analogue methyl-alpha-D-glucopyranoside (MDG) as influenced by quercetin-3-glucoside (isoquercitrin) and quercetin-4'-glucoside (spiraeosid). We found that both glucosides significantly inhibited SGLT-1-mediated MDG uptake whereas the aglycon quercetin or the quercetin-3-rhamnoglucoside (rutin) were ineffective. Calculated apparent kinetic parameters (Km, Vmax) of initial Na+-dependent MDG uptake by the jejunal mucosa indicate a competitive type of inhibition.
Ader
P
P
Institute of Animal Nutrition, Physiology and Metabolism, Christian-Albrechts-University, Olshausenstrasse 40, 24098, Kiel, Germany. ader@aninut.uni-kiel.de
Blöck
M
M
Pietzsch
S
S
Wolffram
S
S
D000409:Alanine / Q000493:pharmacokinetics; D000818:Animals; D066298:In Vitro Techniques; D007408:Intestinal Absorption / Q000187:drug effects / Q000502:physiology; D007413:Intestinal Mucosa / Q000187:drug effects / Q000378:metabolism; D007583:Jejunum / Q000187:drug effects / Q000378:metabolism; D007700:Kinetics; D008562:Membrane Glycoproteins / Q000037:antagonists & inhibitors* / Q000378:metabolism; D008757:Methylglucosides / Q000493:pharmacokinetics; D009004:Monosaccharide Transport Proteins / Q000037:antagonists & inhibitors* / Q000378:metabolism; D011794:Quercetin / Q000031:analogs & derivatives* / Q000494:pharmacology*; D051381:Rats; D017208:Rats, Wistar; D012431:Rutin / Q000494:pharmacology; D012964:Sodium / Q000378:metabolism; D051269:Sodium-Glucose Transporter 1
D008562:Membrane Glycoproteins; D008757:Methylglucosides; D009004:Monosaccharide Transport Proteins; C495676:Slc5a1 protein, rat; D051269:Sodium-Glucose Transporter 1; C016527:isoquercitrin; C027020:methylglucoside; D012431:Rutin; D011794:Quercetin; D012964:Sodium; C080613:spiraeoside; D000409:Alanine