Dietary flavonoids fail to suppress F2-isoprostane formation in vivo

Willcox, Joye K; Catignani, George L.; Roberts, L. Jackson

doi:10.1016/s0891-5849(02)01425-9

Cited by 23 publications

(15 citation statements)

References 42 publications

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“…Consumption of the flavonoids at the doses (mean intake, 25 mg/day) used in this study was without negative effects on animal performance (Table 1), in accordance with results published by other researchers, some of which used even higher doses (23,(35)(36)(37)(38). In this investigation, all three dietary flavonoids substantially increased the blood and liver concentrations of a-T (Table 2).…”

Section: Discussionsupporting

confidence: 90%

Dietary flavonoids with a catechol structure increase α-tocopherol in rats and protect the vitamin from oxidation in vitro

Frank

Budek

Lundh

et al. 2006

Journal of Lipid Research

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To identify dietary phenolic compounds capable of improving vitamin E status, male Sprague-Dawley rats were fed for 4 weeks either a basal diet (control) with 2 g/kg cholesterol and an adequate content of vitamin E or the basal diet fortified with quercetin (Q), (2)-epicatechin (EC), or (1)-catechin (C) at concentrations of 2 g/kg. All three catechol derivatives substantially increased concentrations of a-tocopherol (a-T) in blood plasma and liver. To study potential mechanisms underlying the observed increase of a-T, the capacities of the flavonoids to i ) protect a-T from oxidation in LDL exposed to peroxyl radicals, ii ) reduce a-tocopheroxyl radicals (a-T˙) in SDS micelles, and iii ) inhibit the metabolism of tocopherols in HepG2 cells were determined. All flavonoids protected a-T from oxidation in human LDL ex vivo and dose-dependently reduced the concentrations of a-T˙. None of the test compounds affected vitamin E metabolism in the hepatocyte cultures. In conclusion, fortification of the diet of Sprague-Dawley rats with Q, EC, or C considerably improved their vitamin E status. The underlying mechanism does not appear to involve vitamin E metabolism but may involve direct quenching of free radicals or reduction of the a-T˙by the

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Section: Discussionsupporting

confidence: 90%

Dietary flavonoids with a catechol structure increase α-tocopherol in rats and protect the vitamin from oxidation in vitro

Frank

Budek

Lundh

et al. 2006

Journal of Lipid Research

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“…A small number of in vivo studies indicate that quercetin decreases hepatic lipid peroxidation in rats [15,46], scavenges superoxide generation in rabbit hind-limb ischemic-reperfusion injury [47], decreases UV-light-induced increases in plasma MDA while increasing the levels of reduced glutathione [48], decreases plasma thiobarbituric acid reactive substances and hydroperoxides and restores the activities of superoxide dismutase and catalase to near-normal levels in streptozotocin-induced diabetic rats [49]. In contrast and similar to our results, Willcox et al [50] found that quercetin at 5.0 g/kg diet did not prevent increases in F 2 -isoprostanes, a product of lipid peroxidation, in plasma or hearts of vitamin-E-deficient rats. Consistently, we did not find that quercetin prevented increases in plasma protein carbonyls in vitamin-E-deficient rats, although it has been found to protect apolipoprotein B100 in LDL in vitro against bromine radical-induced oxidation [51].…”

Section: Discussionsupporting

confidence: 89%

Antioxidant activity and metabolite profile of quercetin in vitamin-E-depleted rats

Ameho¹,

Chen²,

Smith³

et al. 2008

The Journal of Nutritional Biochemistry

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“…An increase in plasma vitamin C levels [80,81] was also noted as well as an increase in plasma total antioxidant capacity following CJ intake [80,82]. However, CJ consumption failed to acutely increase endogenous antioxidants [81] or to suppress F2-isoprostane formation, a product of lipid peroxidation, in vivo [83]. Finally, evidence for the presence of salicylates in human plasma after CJ consumption has also been recently reported [84].…”

Section: Bioavailability Of Cranberry Flavonoidsmentioning

confidence: 80%

Evidences of the cardioprotective potential of fruits: The case of cranberries

Ruel

Couillard

2007

Molecular Nutrition Food Res

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Eating a healthy balanced diet, is one of the most important and relevant ways to delay and prevent various health complications including cardiovascular disease (CVD). Among the nutritional factors that have been investigated in recent years, dietary fat intake may be the one that has been most targeted. However, there is also clear epidemiological evidence that increased fruits and vegetables intake can significantly reduce the risk of CVD, an effect that has been suggested to be resulting to a significant extent, from the high polyphenol content of these foods. Numerous polyphenolic compounds such as flavonoids have been identified as having strong antioxidant properties. Most interesting is the fact that, in addition to being one of the largest groups of antioxidant phytochemicals, flavonoids are also an integral part of the human diet as they are found in most fruits and vegetables. Cranberries are one of the most important sources of flavonoids that have a strong antioxidant and anti-inflammatory capacities. Thus, consumption of cranberries or their related products could be of importance not only in the maintenance of health but also in preventing CVD. The following review will present evidences supported for the most part by clinical observations that cranberries can exert potentially healthy effects for your heart.

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Dietary flavonoids fail to suppress F2-isoprostane formation in vivo

Cited by 23 publications

References 42 publications

Dietary flavonoids with a catechol structure increase α-tocopherol in rats and protect the vitamin from oxidation in vitro

Dietary flavonoids with a catechol structure increase α-tocopherol in rats and protect the vitamin from oxidation in vitro

Antioxidant activity and metabolite profile of quercetin in vitamin-E-depleted rats

Evidences of the cardioprotective potential of fruits: The case of cranberries

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