Flavonoid inhibition of sodium-dependent vitamin C transporter 1 (SVCT1) and glucose transporter isoform 2 (GLUT2), intestinal transporters for vitamin C and Glucose.

摘要: Abstract Vitamin C and flavonoids, polyphenols with uncertain function, are abundant in fruits vegetables. We postulated that flavonoids have a novel regulatory action of delaying or inhibiting absorption vitamin glucose, which structurally similar. From six structural classes at least 12 compounds were chosen for studies. investigated the effects selected on intestinal transporter SVCT1(h) by transfecting overexpressing Chinese hamster ovary cells. Flavonoids reversibly inhibited transport transfected cells IC50 values 10–50 μm, concentrations expected to physiologic consequences. The most potent inhibitor class was flavonols, quercetin is foods. Because endogenous transport, we expressed inXenopus laevis oocytes study mechanism inhibition. Quercetin reversible non-competitive ascorbate transport; K i 17.8 μm. GLUT2 oocytes; 22.8 When diabetic rats administered glucose quercetin, hyperglycemia significantly decreased compared administration alone. also normal given plus specific inhibitor, because it did not inhibit sugar transporters GLUT5 SGLT1 injected oocytes. but transported SVCT1(h). Considered together, these data show modulate their respective suggest new function flavonoids.