In this paper, the protective effect of the bioflavonoid quercetin on behaviors, antioxidases, and neurotransmitters in 1-methyl-4-phenyl-1, 2, 3, 6-tetrahydropyridine-(MPTP-) induced Parkinson's disease (PD) was investigated. Quercetin treatment (50 mg/kg, 100 mg/kg and 200 mg/kg body weight) was orally administered for 14 consecutive days. The results show that quercetin treatment markedly im...

The polyphenol quercetin may prevent CVD due to its antihypertensive and vasorelaxant properties. We investigated the effects of quercetin after regular intake on blood pressure (BP) in overweight-to-obese patients with pre-hypertension and stage I hypertension. In addition, the potential mechanisms responsible for the hypothesised effect of quercetin on BP were explored. Subjects (n 70) were r...

      Tribulus terrestris L. var. orientalis (Kerner) G. Beck is widely used in the traditional medicine of many countries. Several flavonoides are identified from the plant material. Aerial parts which collected from northeast of Iran are used in this study. Three flavonoid glycosides were isolated and characterized. The flovonoids were found to be based on quercetin...

The objective is to investigate the influence of PM2.5 exposure on peripheral blood lymphocyte subsets in pregnant mice and the antagonism of quercetin on adverse effects induced by PM2.5 exposure. Pregnant mice were randomly divided into control group, PM2.5 model group and 3 quercetin intervention groups. Dams in all groups except the control group were exposed to PM2.5 suspension by intratra...

The aim of the present study was to compare the ability of the myricetin and quercetin to modulate the oxidative DNA damage induced by 2-amino-3, 8-dimethylimidazo [4,5-f] quinoxaline (8-MeIQx), 2-amino-3, 4, 8-trimethylimidazo [4, 5-f]-quinoxaline (4,8-diMeIQx) and 2-amino-1-methyl-6-phenyl-imidazo [4,5-b] pyridine (PhIP), in human hepatoma cells. DNA damage (strand breaks and oxidized purines...

Quercetin is one of the most abundant polyphenolic flavonoids found in fruits and vegetables and has anti-oxidative and anti-obesity effects. Because the small intestine is a major absorptive organ of dietary nutrients, it is likely that highly concentrated food constituents, including polyphenols, are present in the small intestinal epithelial cells, suggesting that food factors may have a pro...

Etoposide [4'-demethylepipodophyllotoxin-9-(4,6-O-ethylidene)-beta-D-glucopyranoside] is a substrate for P-glycoprotein (P-gp) and cytochrome P450 (CYP) 3A. This study was designed to investigate the effects of quercetin (3,5,7,3',4'-pentahydroxyflavanone), a P-gp and CYP3A inhibitor, on the pharmacokinetics of etoposide in rats. Etoposide was administered to rats orally (9 mg/kg) or i.v. (3 mg...

Quercetin is a natural flavonoid widely distributed in human diet and functional foods. Quercetin 3-O-β-glucuronide (Q3G) is present in wine and some medicinal plants. Quercetin and Q3G may be metabolized from each other in vivo. While quercetin has been the subject of many studies, the pharmacokinetic profiles of quercetin and Q3G (in animals) have not yet been compared. Herein, we prepared a ...

Oxidative stress has been implicated in the pathogenesis of many kinds of neurodegenerative disorders, particularly Parkinson's disease. Quercetin is a bioflavonoid found ubiquitously in fruits and vegetables, and has antioxidative activity. However, the underlying mechanism of the antioxidative effect of quercetin in neurodegenerative diseases has not been well explored. Here, we investigated ...

To investigate the effects of flavonoids on free radical-mediated biological membrane damage and the interaction of flavonoids with heme proteins, we studied the effects of quercetin, its glycosides (rutin and quercetin-3-O-glucoside), morin and (-)epicatechin on the hemolysis of the bovine erythrocytes induced by the hydrophilic free radical initiator, 2,2'-azobis(2-amidinopropane)dihydrochlor...