Metabolic fate of luteolin and its functional activity at focal site.
Luteolin has been shown to possess potent antioxidant and anti-inflammatory/anti-allergic activities. In order to evaluate a chemopreventive role of luteolin in inflammatory responses involved in the pathogenesis of atherosclerosis and cancer etc., the metabolic fate of luteolin in rats and humans was investigated by HPLC analysis, and its effect on cell surface expression of adhesion molecules in human umbilical vein endothelial cells(HUVECs) was examined by ELISA. Luteolin monoglucuronide, which was a main metabolite, and free luteolin were detected in rat plasma and human serum. Luteolin monoglucuronide was hydrolyzed to free luteolin by beta-glucuronidase released from neutrophils stimulated with lonomycin and Cytocharasine B. Luteolin suppressed the TNF-alpha induced ICAM-1 expression significantly. Among nine flavonoids (40 microM) examined, chrysin, apigenine, quercetin and galangin also demonstrated suppressive effct on it. These results suggest the posssibility that deconjugation of luteolin monoglucuronide occurs and that free luteolin showed functional acyivities such as suppression of TNF-alpha induced ICAM- 1 expression at inflammation site.
Shimoi
K
K
School of Food and Nutritional Sciences and Graduate School of Nutritional and Environmental Sciences, University of Shizuoka, Japan. shimoi@smail.u-shizuoka-ken.ac.jp
Saka
N
N
Kaji
K
K
Nozawa
R
R
Kinae
N
N
D000818:Animals; D015815:Cell Adhesion Molecules / Q000032:analysis / Q000378:metabolism; D002462:Cell Membrane / Q000737:chemistry / Q000378:metabolism; D002851:Chromatography, High Pressure Liquid; D004730:Endothelium, Vascular / Q000187:drug effects / Q000378:metabolism; D005419:Flavonoids / Q000097:blood / Q000378:metabolism* / Q000494:pharmacology; D005966:Glucuronidase / Q000378:metabolism; D020719:Glucuronides / Q000097:blood; D006801:Humans; D006868:Hydrolysis; D018799:Intercellular Adhesion Molecule-1 / Q000032:analysis / Q000378:metabolism; D047311:Luteolin; D009504:Neutrophils / Q000201:enzymology; D051381:Rats; D014409:Tumor Necrosis Factor-alpha / Q000494:pharmacology; D014471:Umbilical Veins
D015815:Cell Adhesion Molecules; D005419:Flavonoids; D020719:Glucuronides; D014409:Tumor Necrosis Factor-alpha; D018799:Intercellular Adhesion Molecule-1; D005966:Glucuronidase; D047311:Luteolin