Background: Quercetin is one of the main flavonoids, overall distributed in plants. The antioxidant capacity of quercetin is several times vitamin E and glutathione. This systematic review and meta‐analysis of randomized controlled trials were performed to determine the effect of quercetin on oxidative stress (OS) markers. Methods: A literature search was conducted in PubMed, ISI Web of Science...

The present study was performed to evaluate the role of quercetin in bleomycin (BLM)-induced pulmonary fibrosis (PF) in Sprague-Dawley rats. The rats after BLM administration received quercetin and were sacrificed on the days 12, 22 and 36 to measure the total protein content in bronchoalveolar lavage fluid (BALF). In addition, the hydroxyproline (HYP) content, malondialdehyde (MDA), the GSH/GS...

It is essential to have a thorough knowledge of the bioavailability and metabolism of dietary flavonols to understand their role in disease prevention. Lightly fried onions containing 275 micromol flavonols, principally quercetin-4'-glucoside and quercetin-3,4'-diglucoside, were fed to healthy human volunteers and plasma and urine were collected over a 24 h period. Samples were analysed by HPLC...

Diesel exhaust particles (DEPs) are particulate matter from diesel exhaust that contain many toxic compounds, such as polyaromatic hydrocarbons (PAHs). Some toxicities of PAH are thought to be expressed via aryl hydrocarbon receptors (AhRs). The male reproductive toxicity of DEPs might depend on AhR activation induced by PAHs. We hypothesized that AhR antagonists protect against the male reprod...

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...

Quercetin is a bioflavonoid abundant in onions, apples, tea and red wine and one of the most studied flavonoids. Dietary quercetin intake is suggested to be health promoting, but this assumption is mainly based on mechanistic studies performed in vitro. The objective of this study was to investigate the effect of quercetin on stress-induced changes in oxidative biomarkers in the hypothalamus of...

Insulin sensitivity is partly dependent on insulin-mediated nitric oxide (NO) release and antioxidants may decrease insulin resistance by amelioring NO bioavailability. The effects of chronic therapy with the antioxidant quercetin on blood pressure, vascular function and glucose tolerance in male spontaneously hypertensive rats (SHR), a model of genetically hypertension and insulin resistance, ...

Previous research indicates that ultramarathon exercise can result in blood oxidative stress. The purpose of this investigation was to examine the efficacy of oral supplementation with quercetin, a naturally occurring compound with known antioxidant properties, as a potential countermeasure against blood oxidative stress during an ultramarathon competition. In double-blind fashion, 63 participa...

Quercetin is a plant-derived flavonoid that is widely distributed in nature. The present study is designed to analyze the underlying mechanism in the protection of quercetin against pyrrolizidine alkaloid clivorine-induced acute liver injury in vivo. Serum transaminases, total bilirubin analysis, and liver histological evaluation demonstrated the protection of quercetin against clivorine-induce...