Possible Interaction: Quercetin and Isoquercetin

“The antiviral effects of isoquercetin were greater than that of quercetin with lower IC(50) values and higher in vitro therapeutic index.”

“Consistently, quercetin-3-glucoside inhibited the epinephrine-stimulated activity of adenylyl cyclase in membrane preparations, while quercetin was ineffective.”

“Compared to the quercetin gavage the isoquercitrin gavage consistently produced higher levels of QM in tissues (double to five-fold) as well as in plasma (double to three-fold).”

“Using LC–MS/MS analysis, we found that quercetin and quercetin-7-glucoside underwent dimerization during the antioxidant reaction, potentially leading to a decline in AAs.”

“Combinatorial treatment of the five compounds based on the equivalent concentrations in DMLE showed that significant protection was found only in the cells cotreated with isoquercitrin and quercetin , both of whom showed prominent synergism, as assessed by drug–drug interaction analysis.”

“… Qr in the; Qr group (2,590.5 ± 987.9 mg/L*min), IQ group (2,212.7 ± 914.1 mg/L*…) was larger than the AUC0−t of QG in the; Qr group (1,550.0 ± 454.2 mg/L*min), IQ group (669.3 ± … mg/L*min).”

“A mixture of QT with MR or QG showed interesting combination effect.”

“The free radical scavenging activity of QT was approximately four times higher than MR and two times higher than QG.”

“The synergistic antioxidant activity was obtained when QT was mixed with MR whereas the antagonistic effect was found when mixed with QG.”

“Although the IC50 of isoquercetin as α-glucosidase inhibitor was much higher than that of quercetin, the bioavailability of isoquercetin was higher than that of quercetin.”