The impact of different flavonoid classes on colonic Cl- secretion in rats

Cermak, R Vujicic, Z Scharrer, E Wolfram, S

R. Cermak et al., The impact of different flavonoid classes on colonic Cl- secretion in rats, BIOCH PHARM, 62(8), 2001, pp. 1145-1151

26

INGLESE

Article

Pharmacology & Toxicology

BIOCHEMICAL PHARMACOLOGY

0006-2952 → ACNP

62

8

2001

1145 - 1151

ISI

0006-2952(20011015)62:8<1145:TIODFC>2.0.ZU;2-4

The plant polyphenol quercetin was shown to induce a significant CI- secret ion in intestinal epithelium. In order to elucidate the structural requirem ents of quercetin and related flavonoids for this activity, we tested the a bility of further flavonols and other flavonoids found in edible plants to induce CI- secretion which was measured as an increase in short-circuit cur rent (I-sc) in rat colon. Whereas several flavonols and the flavon luteolin increased I-sc, other flavonoids such as flavanones, flavans, flavanols, a nd anthocyanidins failed to do so. Two glycosides of quercetin, spiraeosid, and isoquercitrin, as well as two methoxylated quercetin metabolites, isor hamnetin and tamarixetin, were also able to increase I-sc. We conclude that a 2,3-double bond in conjunction with the 4-oxo group in the C ring and a hydroxylated B ring are necessary for the secretory activity of flavonoids. This activity requires different structural features than those mandatory for the antioxidative properties of flavonoids. Glucosidation and methoxyla tion of several hydroxyl groups does not necessarily abolish the secretory potential. (C) 2001 Elsevier Science Inc. All rights reserved.