BACKGROUND Quercetin is one of the most potent antioxidants showing anti-inflammatory, antiproliferative and antitumoral effects; however its short half-life in buffered solution (e.g. body fluids) has so far hampered its introduction into clinical practice. AIM To overcome this inconvenience, quercetin was covalently conjugated into a polymethacrylic acid backbone and the conjugate was teste...

The antibacterial activities of flavonoids were found by the paper disk method to be enhanced by combining or mixing them. The combinations of quercetin and quercitrin, quercetin and morin, and quercetin and rutin were much more active than either flavonoid alone. Although rutin did not show activity in itself, the antibacterial activities of quercetin and morin were enhanced in the presence of...

Quercetin, a kind of dietary flavonoid, has shown its anticancer activity in many kinds of cancers including hematological malignancies (acute myelogenous leukemia, chronic myelogenous leukemia, chronic lymphocytic leukemia, and MM) in vitro and in vivo. However, its effects on MM need further investigation. In this study, MM cell lines were treated with quercetin alone or in combination with d...

Introduction: A large body of experimental evidence supports a role for oxidative stress as a mediator of nerve cell death in Parkinson's disease (PD). Flavonoids like quercetin have been reported to prevent neuronal degeneration caused by increased oxidative burden, therefore, this study examined whether quercetin administration at a high dose would attenuate behavioral abnormalities in e...

In addition to parasite spread, the severity of disease observed in cases of human African trypanosomiasis (HAT), or sleeping sickness, is associated with increased levels of inflammatory mediators, including tumor necrosis factor (TNF)-alpha and nitric oxide derivatives. In the present study, quercetin (3,3',4',5,7-pentahydroxyflavone), a potent immunomodulating flavonoid, was shown to directl...

The purpose of this study was to analyze the protective action of natural flavonoid to the reactive oxygen stress on the Band 3 protein by ektacytometry and computational docking technology. For this, quercetin, a major active ingredient of the plum and onions were used as ligand for molecular interaction. The 3D crystallographic structure of molecular target Band 3 was obtained from PDB databa...

OBJECTIVE In order to investigate the pharmacological properties of Ginkgo biloba extract (GBE) on improving blood circulation, the regulating action of GBE and quercetin (a main flavonoid ingredient in GBE) on thrombomodulin (TM) expression and tissue-type plasminogen activator (t-PA) secretion was studied. METHODS Using flow cytometer and gel image system respectively, we evaluated the TM e...

A detailed spectrofluorimetric study on quercetin in aqueous solution proves that its anionic forms are responsible for a strong fluorescence enhancement observed at pH > 6. Anion fluorescence is also observed in organic solvents with strong hydrogen bond acceptor properties. The results provide a new interpretation of biophysical and analytical literature data where the fluorescence of the ani...

We investigated a molecular mechanism underlying quercetin-mediated amelioration of colonic mucosal injury and analyzed chemical structure contributing to the quercetin's effect. Quercetin up-regulated vascular endothelial growth factor (VEGF), an ulcer healing factor, not only in colon epithelial cell lines but also in the inflamed colonic tissue. VEGF derived from quercetin-treated colon epit...

Herein we investigated the molecular mechanism of action of the citrus flavonoid, quercetin in skeletal muscle cells (L6 myotubes). Taking advantage of protein kinase inhibitors, we proved that the effect of quercetin on 2-NBDG uptake in L6 myotubes was not through insulin signaling pathway, but through adenosine monophosphate kinase (AMPK) pathway and its downstream target p38 MAPK. An increas...