Flavonoids are polyphenolic compounds that occur ubiquitously in foods of plant origin.
Over 4.000 different flavonoids have been described. and they are categorized into flavonols, flavones, catechins, flavanones, anthocyanidins and isoflavonoids.
Flavonoids have a variety of biological effects in numerous mammalian cell systems, in vitro as well in vivo.
Recently, much attention has been paid to their antioxidant properties and to their inhibitory role in various stages of tumour development in animal studies.
Quercetin, the major representative of the flavonol subclass, is a strong antioxidant, and prevents oxidation of low density lipoproteins in vitro.
Oxidized low density lipoproteins are atherogenic, and are considered to be a crucial intermediate in the formation of atherosclerotic plaques.
This agrees with observations in epidemiological studies that the intake of flavonols and flavones was inversely associated with subsequent coronary heart disease.
However, no effects of flavonols on cancer were found in these studies.
The extent of absorption of flavonoids is an important unsolved problem in judging their many alleged health effects.
Flavonoids present in foods were considered non-absorbable because they are bound to sugars as B-glycosides.
Only free flavonoids without a sugar molecule, the so-called aglycones, were thought to be able to pass through the gut wall. (...)
Mots-clés Pascal : Flavonoïde, Alimentation, Origine végétale, Antioxydant, Quercétine, Homme, Cardiopathie coronaire, In vitro, In vivo, Epidémiologie, Absorption, Métabolisme, Pharmacocinétique, Prévention, Etude générale, Appareil circulatoire pathologie, Tumeur maligne
Mots-clés Pascal anglais : Flavonoid, Feeding, Plant origin, Antioxidant, Quercetin, Human, Coronary heart disease, In vitro, In vivo, Epidemiology, Absorption, Metabolism, Pharmacokinetics, Prevention, General study, Cardiovascular disease, Malignant tumor
Notice produite par :
Inist-CNRS - Institut de l'Information Scientifique et Technique
Cote : 97-0506225
Code Inist : 002B02N. Création : 13/02/1998.