In-vitro sulfation of piceatannol by human liver cytosol and recombinant sulfotransferases.
OBJECTIVE
The aim of this study was to investigate the concentration-dependent sulfation of piceatannol, a dietary polyphenol present in grapes and wine and known for its promising anticancer and anti-inflammatory activity.


METHODS
Sulfation of piceatannol was investigated in human liver cytosol as well as using a panel of recombinant sulfotransferase isoforms. Furthermore, the chemical structures of novel sulfates were identified by liquid chromatography/mass spectrometry (LC/MS).


RESULTS
In the presence of 3'-phosphoadenosine-5'-phosphosulfate, three metabolites could be detected whose structures were identified by LC/MS/MS as piceatannol disulfate (M1) and two monosulfates (M2, M3). The kinetics of M1 formation exhibited a pattern of substrate inhibition with a Ki of 21.8 +/- 11.3 microm and a Vmax/Km of 7.63 +/- 1.80 microl/mg protein per min. Formation of M2 and M3 showed sigmoidal kinetics with apparent Km and Vmax values of 27.1 +/- 2.90 microm and 118.4 +/- 4.38 pmol/mg protein per min, respectively, for M2; and 35.7 +/- 2.70 microm and 81.8 +/- 2.77 pmol/mg protein per min, respectively, for M3. Incubation in the presence of human recombinant sulfotransferases (SULTs) demonstrated that M1 was formed equally by SULT1A1*1 and SULT1B1 and to a lesser extent by SULT1A1*2. M2 was preferentially catalysed by SULT1A1*2, 1A3 and 1E1. The formation of M3, however, was mainly catalysed by SULT1A2*1 and SULT1A3.


CONCLUSIONS
Our results elucidate the importance of piceatannol sulfation in human liver, which must be taken into account in humans after dietary intake of piceatannol.
Miksits
Michaela
M
Department of Clinical Pharmacy and Diagnostics, University of Vienna, Vienna, Austria.
Sulyok
Michael
M
Schuhmacher
Rainer
R
Szekeres
Thomas
T
Jäger
Walter
W
D000284:Administration, Oral; D015239:Arylsulfotransferase / Q000378:metabolism; D002851:Chromatography, High Pressure Liquid / Q000379:methods; D003600:Cytosol / Q000737:chemistry / Q000378:metabolism*; D019587:Dietary Supplements; D004305:Dose-Response Relationship, Drug; D005419:Flavonoids / Q000737:chemistry / Q000378:metabolism / Q000494:pharmacology; D022781:Hepatocytes / Q000378:metabolism*; D006801:Humans; D007700:Kinetics; D013058:Mass Spectrometry / Q000379:methods; D015394:Molecular Structure; D010636:Phenols / Q000737:chemistry / Q000378:metabolism / Q000494:pharmacology; D010724:Phosphoadenosine Phosphosulfate / Q000378:metabolism / Q000494:pharmacology; D059808:Polyphenols; D011994:Recombinant Proteins / Q000737:chemistry / Q000378:metabolism / Q000494:pharmacology; D013267:Stilbenes / Q000737:chemistry / Q000378:metabolism* / Q000494:pharmacology; D013431:Sulfates / Q000378:metabolism*; D015238:Sulfotransferases / Q000737:chemistry / Q000378:metabolism / Q000494:pharmacology*
D005419:Flavonoids; D010636:Phenols; D059808:Polyphenols; D011994:Recombinant Proteins; D013267:Stilbenes; D013431:Sulfates; D010724:Phosphoadenosine Phosphosulfate; C041525:3,3',4,5'-tetrahydroxystilbene; D015238:Sulfotransferases; C109377:iodothyronine sulfotransferase; D015239:Arylsulfotransferase; C117544:SULT1A1 protein, human; C513290:SULT1A2 protein, human; C020122:estrone sulfotransferase