Quercetin glucuronidation

Wittig, J., Herderich, M., Graefe, E.U., and Veit, M., Identification of quercetin glucuronides in human plasma by high-performance liquid chromatography-tandem mass spectrometry, J. Chromatogr. B Biomed. Sci. AppL, 753, 237, 2001. 

Yoshizumi, M., Tsuchiya, K., Suzaki, Y., Kirima, K., Kyaw, M., Moon, J.H., Terao, J., and Tamaki, T., Quercetin glucuronide prevents VSMC hypertrophy by angiotensin II via the inhibition of JNK and AP-1 signaling pathway, Bioehem. Biophys. Res. Commun., 293, 1458, 2002. 

Day, A.J. et al.. Conjugation position of quercetin glucuronides and effect on biological activity. Free Radical Biol Med, 29, 1234, 2000. 

Kawai Y, Nishikawa T, Shiba Y, Saito S, Murota K, Shibata N, Kobayashi M, Kanayama M, Uchida K, Terao J. 2008. Macrophage as a target of quercetin glucuronides in human atherosclerotic arteries Implication in the anti-atherosclero-tic mechanism of dietary flavonoids. J Biol Chem 283 9424-9434. 

Lee-Hilz YY, Stolaki M, van Berkel WJ, Aarts JM, Rietjens IM. 2008. Activation of EpRE-mediated gene transcription by quercetin glucuronides depends on their deconjugation. Food Chem Toxicol. 

However, the effect of piperine on SULT and flavonoid status across the life cycle remains to be investigated. Induction of phase II metabolism appears to decrease the bioavailability and accelerate the excretion of flavonoids. For example, Siess et al.115 and Walle et al.116 reported flavones induced rat hepatic UGT activity in HepG2 and Caco-2 cells. This induction of UGT enhanced quercetin glucuronidation in Caco-2 cells. In addition to inducing UGT activity, the flavone chrysin inhibits hepatic SULT-mediated sulfation of acetaminophen and minoxidol." The impact of chrysin on the capacity of COMT action toward flavonoids has not been examined. Further, the effect of age on phase II modulation by piperine and chrysin has not been reported. Thus, information on the relationship between age and intake of flavonoids and other phytochemicals that also affect phase II metabolism is required. 

Hepatic 3-glucuronidase is active on quercetin glucuronides in a liver cell model and was enhanced in the presence of methylation inhibitors. 

Sesink, A.L., O Leary, K.A., and Hollman, P.C., Quercetin glucuronides but not glucosides are present in human plasma after consumption of quercetin-3-glucoside or quercetin-4 -glucoside, J. Nutr, 131, 1938, 2001. 

O Leary, K.A., Day, A.J., Needs, RW., O Brien, N.M., and Williamson, G., Metabolism of quercetin glucuronides in an in vitro cell model, in Biologically-Active Phytochemicals in Foods Analysis, Metabolism, Bioavailability and Function, W. Pfannhauser, G.R. Fenwick, and S. Khokhar, Eds., Royal Society of Chemistry, Cambridge, U.K., pp. 441 142, 2001. 

Figure 2.16 HPLC profile of flavonols of a Cabernet Sauvignon grape skins extract recorded at wavelength 360nm. (1) myricetin glucuronide, (2) myricetin gluco-side, (3) quercetin glucuronide, (4) quercetin glucoside, (5) quercetin rutinoside, (6) kaempferol glucuronide, (7) kaempferol glucoside, (8) unidentified flavonol...

Chao, P.D. et al.. Quercetin glucuronides inhibited 2-aminofluorene acetylation in human acute myeloid HL-60 leukemia cells, Phytomedicine, 9, 625,2002. 

Kawai, Y., Nishikawa, T., Shiba, T. et al. (2008a). Macrophages as a target of quercetin glucuronides in human atherosclerotic arteries. Journal of Biological Chemistry, 283, 9424-9434. 

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