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Gary Williamson - One of the best experts on this subject based on the ideXlab platform.
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metabolism of quercetin 7 and quercetin 3 glucuronides by an in vitro hepatic model the role of human β glucuronidase sulfotransferase catechol o methyltransferase and multi resistant protein 2 mrp2 in flavonoid metabolism
Biochemical Pharmacology, 2003Co-Authors: Karen Oleary, Nora M Obrien, Paul W. Needs, Fred A Mellon, Gary WilliamsonAbstract:Abstract Quercetin-3- and quercetin-7-glucuronides are major products of small Intestine epithelial cell metabolism (J. Nutr. 130 (2000) 2765) but it is not known if quercetin glucuronides can be further processed in the liver or if they are excreted directly. Using the HepG2 hepatic cell model, we show that highly purified quercetin-7- and quercetin-3-glucuronides can follow two pathways of metabolism: (i) methylation of the catechol functional group of both quercetin glucuronides (44% of quercetin-7-glucuronide at a rate of 2.6 nmol/hr/10 6 cells, and 32% of quercetin-3-glucuronide at a rate of 1.9 nmol/hr/10 6 cells, over 48 hr) or (ii) hydrolysis of the glucuronide by endogenous β-glucuronidase followed by sulfation to quercetin-3′-sulfate (7% of quercetin-7-glucuronide at a rate of 0.42 nmol/hr/10 6 cells and 10% of quercetin-3-glucuronide at a rate of 0.61 nmol/hr/10 6 cells, over 48 hr). In contrast, quercetin-4′-glucuronide was not metabolised, and interestingly this is not a major product of the small Intestine Absorption process. The conversion of the quercetin-7- and quercetin-3-glucuronide to the mono-sulfate conjugate shows intracellular deglucuronidation by β-glucuronidase activity, allowing transient contact of the free aglycone with the cellular environment. Inhibition of methylation using a catechol- O -methyltransferase inhibitor shifted metabolism towards sulfation, as indicated by an increase in quercetin-3′-sulfate formation (increase in rate to 1.13 and 1.43 nmol/hr/10 6 cells for quercetin-7-glucuronide and quercetin-3-glucuronide, respectively). Efflux of quercetin metabolites from HepG2 cells (methylated glucuronide and sulfate conjugates) was not altered by verapamil, a p -glycoprotein inhibitor, but efflux was competitively inhibited by MK-571, a multidrug resistant protein inhibitor, indicating a role for multidrug resistant protein in the efflux of quercetin conjugates from HepG2 cells. These results show that HepG2 cells can absorb and turnover quercetin glucuronides and that human endogenous β-glucuronidase activity could modulate the intracellular biological activities of dietary antioxidant flavonoids.
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metabolism of quercetin 7 and quercetin 3 glucuronides by an in vitro hepatic model the role of human β glucuronidase sulfotransferase catechol o methyltransferase and multi resistant protein 2 mrp2 in flavonoid metabolism
Biochemical Pharmacology, 2003Co-Authors: Karen A Oleary, Nora M Obrien, Paul W. Needs, Fred A Mellon, Andrea J Day, Gary WilliamsonAbstract:Quercetin-3- and quercetin-7-glucuronides are major products of small Intestine epithelial cell metabolism (J. Nutr. 130 (2000) 2765) but it is not known if quercetin glucuronides can be further processed in the liver or if they are excreted directly. Using the HepG2 hepatic cell model, we show that highly purified quercetin-7- and quercetin-3-glucuronides can follow two pathways of metabolism: (i) methylation of the catechol functional group of both quercetin glucuronides (44% of quercetin-7-glucuronide at a rate of 2.6 nmol/hr/10(6) cells, and 32% of quercetin-3-glucuronide at a rate of 1.9 nmol/hr/10(6) cells, over 48 hr) or (ii) hydrolysis of the glucuronide by endogenous beta-glucuronidase followed by sulfation to quercetin-3'-sulfate (7% of quercetin-7-glucuronide at a rate of 0.42 nmol/hr/10(6) cells and 10% of quercetin-3-glucuronide at a rate of 0.61 nmol/hr/10(6) cells, over 48 hr). In contrast, quercetin-4'-glucuronide was not metabolised, and interestingly this is not a major product of the small Intestine Absorption process. The conversion of the quercetin-7- and quercetin-3-glucuronide to the mono-sulfate conjugate shows intracellular deglucuronidation by beta-glucuronidase activity, allowing transient contact of the free aglycone with the cellular environment. Inhibition of methylation using a catechol-O-methyltransferase inhibitor shifted metabolism towards sulfation, as indicated by an increase in quercetin-3'-sulfate formation (increase in rate to 1.13 and 1.43 nmol/hr/10(6) cells for quercetin-7-glucuronide and quercetin-3-glucuronide, respectively). Efflux of quercetin metabolites from HepG2 cells (methylated glucuronide and sulfate conjugates) was not altered by verapamil, a p-glycoprotein inhibitor, but efflux was competitively inhibited by MK-571, a multidrug resistant protein inhibitor, indicating a role for multidrug resistant protein in the efflux of quercetin conjugates from HepG2 cells. These results show that HepG2 cells can absorb and turnover quercetin glucuronides and that human endogenous beta-glucuronidase activity could modulate the intracellular biological activities of dietary antioxidant flavonoids.
Karen Oleary - One of the best experts on this subject based on the ideXlab platform.
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metabolism of quercetin 7 and quercetin 3 glucuronides by an in vitro hepatic model the role of human β glucuronidase sulfotransferase catechol o methyltransferase and multi resistant protein 2 mrp2 in flavonoid metabolism
Biochemical Pharmacology, 2003Co-Authors: Karen Oleary, Nora M Obrien, Paul W. Needs, Fred A Mellon, Gary WilliamsonAbstract:Abstract Quercetin-3- and quercetin-7-glucuronides are major products of small Intestine epithelial cell metabolism (J. Nutr. 130 (2000) 2765) but it is not known if quercetin glucuronides can be further processed in the liver or if they are excreted directly. Using the HepG2 hepatic cell model, we show that highly purified quercetin-7- and quercetin-3-glucuronides can follow two pathways of metabolism: (i) methylation of the catechol functional group of both quercetin glucuronides (44% of quercetin-7-glucuronide at a rate of 2.6 nmol/hr/10 6 cells, and 32% of quercetin-3-glucuronide at a rate of 1.9 nmol/hr/10 6 cells, over 48 hr) or (ii) hydrolysis of the glucuronide by endogenous β-glucuronidase followed by sulfation to quercetin-3′-sulfate (7% of quercetin-7-glucuronide at a rate of 0.42 nmol/hr/10 6 cells and 10% of quercetin-3-glucuronide at a rate of 0.61 nmol/hr/10 6 cells, over 48 hr). In contrast, quercetin-4′-glucuronide was not metabolised, and interestingly this is not a major product of the small Intestine Absorption process. The conversion of the quercetin-7- and quercetin-3-glucuronide to the mono-sulfate conjugate shows intracellular deglucuronidation by β-glucuronidase activity, allowing transient contact of the free aglycone with the cellular environment. Inhibition of methylation using a catechol- O -methyltransferase inhibitor shifted metabolism towards sulfation, as indicated by an increase in quercetin-3′-sulfate formation (increase in rate to 1.13 and 1.43 nmol/hr/10 6 cells for quercetin-7-glucuronide and quercetin-3-glucuronide, respectively). Efflux of quercetin metabolites from HepG2 cells (methylated glucuronide and sulfate conjugates) was not altered by verapamil, a p -glycoprotein inhibitor, but efflux was competitively inhibited by MK-571, a multidrug resistant protein inhibitor, indicating a role for multidrug resistant protein in the efflux of quercetin conjugates from HepG2 cells. These results show that HepG2 cells can absorb and turnover quercetin glucuronides and that human endogenous β-glucuronidase activity could modulate the intracellular biological activities of dietary antioxidant flavonoids.
Raquel Mateos - One of the best experts on this subject based on the ideXlab platform.
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Flavanol Bioavailability in Two Cocoa Products with Different Phenolic Content. A Comparative Study in Humans.
Nutrients, 2019Co-Authors: Miren Gómez-juaristi, Beatriz Sarriá, Sara Martínez-lópez, Laura Bravo Clemente, Raquel MateosAbstract:Cocoa has beneficial health effects partly due to its high flavanol content. This study was aimed at assessing the Absorption and metabolism of polyphenols in two soluble cocoa products: a conventional (CC) and a flavanol-rich product (CC-PP). A crossover, randomized, blind study was performed in 13 healthy men and women. On two different days, after an overnight fast, volunteers consumed one serving of CC (15 g) or CC-PP (25 g) in 200 mL of semi-skimmed milk containing 19.80 mg and 68.25 mg of flavanols, respectively. Blood and urine samples were taken, before and after CC and CC-PP consumption, and analyzed by high-performance liquid chromatography coupled to electrospray ionisation and quadrupole time-of-flight mass spectrometry (HPLC-ESI-QToF-MS). Up to 10 and 30 metabolites were identified in plasma and urine, respectively. Phase II derivatives of epicatechin were identified with kinetics compatible with small Intestine Absorption, although the most abundant groups of metabolites were phase II derivatives of phenyl-γ-valerolactone and phenylvaleric acid, formed at colonic level. 5-(4′-Hydroxyphenyl)-γ-valerolactone-sulfate could be a sensitive biomarker of cocoa flavanol intake. CC and CC-PP flavanols showed a dose-dependent Absorption with a recovery of 35%. In conclusion, cocoa flavanols are moderately bioavailable and extensively metabolized, mainly by the colonic microbiota.
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bioavailability of hydroxycinnamates in an instant green roasted coffee blend in humans identification of novel colonic metabolites
Food & Function, 2018Co-Authors: Miren Gomezjuaristi, Beatriz Sarriá, Sara Martinezlopez, Laura Bravo, Raquel MateosAbstract:Roasting greatly reduces the phenolic content in green coffee beans. Considering the beneficial effects of coffee polyphenols, blends containing green coffee beans are being consumed as a healthier alternative to roasted coffee. This study was aimed at assessing the Absorption and metabolism of hydroxycinnamates in an instant green/roasted (35/65) coffee blend in healthy humans. Twelve fasting men and women consumed a cup of coffee containing 269.5 mg (760.6 μmol) of chlorogenic acids. Blood and urine samples were taken before and after coffee consumption at different times and analyzed by LC-MS-QToF. Up to 25 and 42 metabolites were identified in plasma and urine, respectively, mainly in the form of sulfate and methyl derivatives, and to a lower extent as glucuronides. Un-metabolized hydroxycinnamate esters (caffeoyl-, feruloyl-, and coumaroylquinic acids), hydroxycinnamic acids (caffeic, ferulic and coumaric acids) and their phase II metabolites, in addition to phase II derivatives of lactones, represented a minor group of metabolites (16.3% of the metabolites excreted in urine) with kinetics compatible with small Intestine Absorption. Dihydrohydroxycinnamic acids and their phase II derivatives, in addition to feruloylglycine, showed delayed kinetics due to their colonic origin and represented the most abundant group of metabolites (75.7% of total urinary metabolites). Dihydrohydroxycinnamate esters (dihydroferuloyl-, dihydrocaffeoyl- and dihydrocoumaroylquinic acids) have been identified for the first time in both plasma and urine, with microbial origin (excreted 8–12 h after coffee intake) amounting to 8% of total urinary metabolites. In conclusion, coffee polyphenols are partially bioavailable and extensively metabolized, mainly by the colonic microbiota.
Nora M Obrien - One of the best experts on this subject based on the ideXlab platform.
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metabolism of quercetin 7 and quercetin 3 glucuronides by an in vitro hepatic model the role of human β glucuronidase sulfotransferase catechol o methyltransferase and multi resistant protein 2 mrp2 in flavonoid metabolism
Biochemical Pharmacology, 2003Co-Authors: Karen Oleary, Nora M Obrien, Paul W. Needs, Fred A Mellon, Gary WilliamsonAbstract:Abstract Quercetin-3- and quercetin-7-glucuronides are major products of small Intestine epithelial cell metabolism (J. Nutr. 130 (2000) 2765) but it is not known if quercetin glucuronides can be further processed in the liver or if they are excreted directly. Using the HepG2 hepatic cell model, we show that highly purified quercetin-7- and quercetin-3-glucuronides can follow two pathways of metabolism: (i) methylation of the catechol functional group of both quercetin glucuronides (44% of quercetin-7-glucuronide at a rate of 2.6 nmol/hr/10 6 cells, and 32% of quercetin-3-glucuronide at a rate of 1.9 nmol/hr/10 6 cells, over 48 hr) or (ii) hydrolysis of the glucuronide by endogenous β-glucuronidase followed by sulfation to quercetin-3′-sulfate (7% of quercetin-7-glucuronide at a rate of 0.42 nmol/hr/10 6 cells and 10% of quercetin-3-glucuronide at a rate of 0.61 nmol/hr/10 6 cells, over 48 hr). In contrast, quercetin-4′-glucuronide was not metabolised, and interestingly this is not a major product of the small Intestine Absorption process. The conversion of the quercetin-7- and quercetin-3-glucuronide to the mono-sulfate conjugate shows intracellular deglucuronidation by β-glucuronidase activity, allowing transient contact of the free aglycone with the cellular environment. Inhibition of methylation using a catechol- O -methyltransferase inhibitor shifted metabolism towards sulfation, as indicated by an increase in quercetin-3′-sulfate formation (increase in rate to 1.13 and 1.43 nmol/hr/10 6 cells for quercetin-7-glucuronide and quercetin-3-glucuronide, respectively). Efflux of quercetin metabolites from HepG2 cells (methylated glucuronide and sulfate conjugates) was not altered by verapamil, a p -glycoprotein inhibitor, but efflux was competitively inhibited by MK-571, a multidrug resistant protein inhibitor, indicating a role for multidrug resistant protein in the efflux of quercetin conjugates from HepG2 cells. These results show that HepG2 cells can absorb and turnover quercetin glucuronides and that human endogenous β-glucuronidase activity could modulate the intracellular biological activities of dietary antioxidant flavonoids.
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metabolism of quercetin 7 and quercetin 3 glucuronides by an in vitro hepatic model the role of human β glucuronidase sulfotransferase catechol o methyltransferase and multi resistant protein 2 mrp2 in flavonoid metabolism
Biochemical Pharmacology, 2003Co-Authors: Karen A Oleary, Nora M Obrien, Paul W. Needs, Fred A Mellon, Andrea J Day, Gary WilliamsonAbstract:Quercetin-3- and quercetin-7-glucuronides are major products of small Intestine epithelial cell metabolism (J. Nutr. 130 (2000) 2765) but it is not known if quercetin glucuronides can be further processed in the liver or if they are excreted directly. Using the HepG2 hepatic cell model, we show that highly purified quercetin-7- and quercetin-3-glucuronides can follow two pathways of metabolism: (i) methylation of the catechol functional group of both quercetin glucuronides (44% of quercetin-7-glucuronide at a rate of 2.6 nmol/hr/10(6) cells, and 32% of quercetin-3-glucuronide at a rate of 1.9 nmol/hr/10(6) cells, over 48 hr) or (ii) hydrolysis of the glucuronide by endogenous beta-glucuronidase followed by sulfation to quercetin-3'-sulfate (7% of quercetin-7-glucuronide at a rate of 0.42 nmol/hr/10(6) cells and 10% of quercetin-3-glucuronide at a rate of 0.61 nmol/hr/10(6) cells, over 48 hr). In contrast, quercetin-4'-glucuronide was not metabolised, and interestingly this is not a major product of the small Intestine Absorption process. The conversion of the quercetin-7- and quercetin-3-glucuronide to the mono-sulfate conjugate shows intracellular deglucuronidation by beta-glucuronidase activity, allowing transient contact of the free aglycone with the cellular environment. Inhibition of methylation using a catechol-O-methyltransferase inhibitor shifted metabolism towards sulfation, as indicated by an increase in quercetin-3'-sulfate formation (increase in rate to 1.13 and 1.43 nmol/hr/10(6) cells for quercetin-7-glucuronide and quercetin-3-glucuronide, respectively). Efflux of quercetin metabolites from HepG2 cells (methylated glucuronide and sulfate conjugates) was not altered by verapamil, a p-glycoprotein inhibitor, but efflux was competitively inhibited by MK-571, a multidrug resistant protein inhibitor, indicating a role for multidrug resistant protein in the efflux of quercetin conjugates from HepG2 cells. These results show that HepG2 cells can absorb and turnover quercetin glucuronides and that human endogenous beta-glucuronidase activity could modulate the intracellular biological activities of dietary antioxidant flavonoids.
Paul W. Needs - One of the best experts on this subject based on the ideXlab platform.
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metabolism of quercetin 7 and quercetin 3 glucuronides by an in vitro hepatic model the role of human β glucuronidase sulfotransferase catechol o methyltransferase and multi resistant protein 2 mrp2 in flavonoid metabolism
Biochemical Pharmacology, 2003Co-Authors: Karen Oleary, Nora M Obrien, Paul W. Needs, Fred A Mellon, Gary WilliamsonAbstract:Abstract Quercetin-3- and quercetin-7-glucuronides are major products of small Intestine epithelial cell metabolism (J. Nutr. 130 (2000) 2765) but it is not known if quercetin glucuronides can be further processed in the liver or if they are excreted directly. Using the HepG2 hepatic cell model, we show that highly purified quercetin-7- and quercetin-3-glucuronides can follow two pathways of metabolism: (i) methylation of the catechol functional group of both quercetin glucuronides (44% of quercetin-7-glucuronide at a rate of 2.6 nmol/hr/10 6 cells, and 32% of quercetin-3-glucuronide at a rate of 1.9 nmol/hr/10 6 cells, over 48 hr) or (ii) hydrolysis of the glucuronide by endogenous β-glucuronidase followed by sulfation to quercetin-3′-sulfate (7% of quercetin-7-glucuronide at a rate of 0.42 nmol/hr/10 6 cells and 10% of quercetin-3-glucuronide at a rate of 0.61 nmol/hr/10 6 cells, over 48 hr). In contrast, quercetin-4′-glucuronide was not metabolised, and interestingly this is not a major product of the small Intestine Absorption process. The conversion of the quercetin-7- and quercetin-3-glucuronide to the mono-sulfate conjugate shows intracellular deglucuronidation by β-glucuronidase activity, allowing transient contact of the free aglycone with the cellular environment. Inhibition of methylation using a catechol- O -methyltransferase inhibitor shifted metabolism towards sulfation, as indicated by an increase in quercetin-3′-sulfate formation (increase in rate to 1.13 and 1.43 nmol/hr/10 6 cells for quercetin-7-glucuronide and quercetin-3-glucuronide, respectively). Efflux of quercetin metabolites from HepG2 cells (methylated glucuronide and sulfate conjugates) was not altered by verapamil, a p -glycoprotein inhibitor, but efflux was competitively inhibited by MK-571, a multidrug resistant protein inhibitor, indicating a role for multidrug resistant protein in the efflux of quercetin conjugates from HepG2 cells. These results show that HepG2 cells can absorb and turnover quercetin glucuronides and that human endogenous β-glucuronidase activity could modulate the intracellular biological activities of dietary antioxidant flavonoids.
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metabolism of quercetin 7 and quercetin 3 glucuronides by an in vitro hepatic model the role of human β glucuronidase sulfotransferase catechol o methyltransferase and multi resistant protein 2 mrp2 in flavonoid metabolism
Biochemical Pharmacology, 2003Co-Authors: Karen A Oleary, Nora M Obrien, Paul W. Needs, Fred A Mellon, Andrea J Day, Gary WilliamsonAbstract:Quercetin-3- and quercetin-7-glucuronides are major products of small Intestine epithelial cell metabolism (J. Nutr. 130 (2000) 2765) but it is not known if quercetin glucuronides can be further processed in the liver or if they are excreted directly. Using the HepG2 hepatic cell model, we show that highly purified quercetin-7- and quercetin-3-glucuronides can follow two pathways of metabolism: (i) methylation of the catechol functional group of both quercetin glucuronides (44% of quercetin-7-glucuronide at a rate of 2.6 nmol/hr/10(6) cells, and 32% of quercetin-3-glucuronide at a rate of 1.9 nmol/hr/10(6) cells, over 48 hr) or (ii) hydrolysis of the glucuronide by endogenous beta-glucuronidase followed by sulfation to quercetin-3'-sulfate (7% of quercetin-7-glucuronide at a rate of 0.42 nmol/hr/10(6) cells and 10% of quercetin-3-glucuronide at a rate of 0.61 nmol/hr/10(6) cells, over 48 hr). In contrast, quercetin-4'-glucuronide was not metabolised, and interestingly this is not a major product of the small Intestine Absorption process. The conversion of the quercetin-7- and quercetin-3-glucuronide to the mono-sulfate conjugate shows intracellular deglucuronidation by beta-glucuronidase activity, allowing transient contact of the free aglycone with the cellular environment. Inhibition of methylation using a catechol-O-methyltransferase inhibitor shifted metabolism towards sulfation, as indicated by an increase in quercetin-3'-sulfate formation (increase in rate to 1.13 and 1.43 nmol/hr/10(6) cells for quercetin-7-glucuronide and quercetin-3-glucuronide, respectively). Efflux of quercetin metabolites from HepG2 cells (methylated glucuronide and sulfate conjugates) was not altered by verapamil, a p-glycoprotein inhibitor, but efflux was competitively inhibited by MK-571, a multidrug resistant protein inhibitor, indicating a role for multidrug resistant protein in the efflux of quercetin conjugates from HepG2 cells. These results show that HepG2 cells can absorb and turnover quercetin glucuronides and that human endogenous beta-glucuronidase activity could modulate the intracellular biological activities of dietary antioxidant flavonoids.
