Disposition and metabolism of the flavonoid chrysin in normal volunteers.
OBJECTIVE
To describe the oral disposition of the dietary flavonoid chrysin in healthy volunteers.


METHODS
Oral 400 mg doses of chrysin were administered to seven subjects. Chrysin and metabolites were assayed in plasma, urine and faeces by h.p.l.c.


RESULTS
Peak plasma chrysin concentrations were only 3-16 ng ml(-1) with AUCs of 5-193 ng ml(-1) h. Plasma chrysin sulphate concentrations were 30-fold higher (AUC 450-4220 ng ml(-1) h). In urine, chrysin and chrysin glucuronide accounted for 0.2-3.1 mg and 2-26 mg, respectively. Most of the dose appeared in faeces as chrysin. Parallel experiments in rats showed high bile concentrations of chrysin conjugates.


CONCLUSIONS
These findings, together with previous data using Caco-2 cells, suggest that chrysin has low oral bioavailability, mainly due to extensive metabolism and efflux of metabolites back into the intestine for hydrolysis and faecal elimination.
Department of Cell and Molecular Pharmacology and Experimental Therapeutics, Division of Clinical Pharmacology, Medical University of South Carolina, Charleston, SC 29425, USA. wallet@musc.edu
T
T
Walle
Y
Y
Otake
J A
JA
Brubaker
U K
UK
Walle
P V
PV
Halushka
D000284:Administration, Oral; D000328:Adult; D000818:Animals; D019380:Anti-HIV Agents / Q000378:metabolism / Q000493:pharmacokinetics*; D005419:Flavonoids / Q000378:metabolism / Q000493:pharmacokinetics*; D006801:Humans; D008297:Male; D023421:Models, Animal; D051381:Rats; D017207:Rats, Sprague-Dawley
D019380:Anti-HIV Agents; D005419:Flavonoids; C043561:chrysin