Glucuronosyltransferase (UGT)
Glucuronosyltransferase (UGT) is a glycosyltransferase (EC 2.4.1.17) also known as UDP-glucuronosyltransferase, that catalyzes the addition of a glycosyl group from a UTP-sugar to a small hydrophobic molecule.
Although the majority of UGT enzymes are expressed in the liver, UGT1A7, UGT1A8, and UGT1A10 are expressed exclusively extrahepatically, mainly in the intestine. UGT1A9, UGT2B7, and UGT2B11 are expressed at relatively high amounts in the kidney.[6]
Glucuronosyltransferase catalyzes the conversion of 1-naphthol + UDPglucuronate to 1-naphthyl-O-glucuronide + UDP.
Substrate | UGT | End Product |
---|---|---|
1-Naphthol | 1-naphthyl-O-glucuronide | |
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Cofactor | Byproduct | |
UDPglucuronate | UDP | |
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UGT1A1
Inhibitors | Strength | Dosage | Verified in Man |
---|---|---|---|
Andrographis paniculata | 50% [11] | IC50 5.00 micorg/mL | ? |
Genistein (in Kudzu) | 96.7% Inhibition [12] | 30 μM | ? |
Isoliquiritigenin (in licorice) | 95.2% [8] | 100 μM | ? |
Liquiritigenin (in licorice) | K(i) 9.1 μM [9] | ? | ? |
Silybin | IC50 1.4 µM [6] | ? | ? |
Silymarin [6] | ? | ? | ? |
Valerenic acid [6] | ? | ? | ? |
Valerian root [6] | ? | ? | ? |
UGT1A3
Inhibitors | Strength | Dosage | Verified in Man |
---|---|---|---|
Andrographis paniculata | 50% [11] | 1.70 microg/mL | ? |
Genistein (in Kudzu) | 47.4% Inhibition [12] | 30 μM | ? |
Glycyrrhetinic acid (in licorice) | K(i) 0.2 μM [10] | ? | ? |
Isoliquiritigenin (in licorice) | 76.1% [8] | 100 μM | ? |
UGT1A4
Inhibitors | Strength | Dosage | Verified in Man |
---|---|---|---|
EGCG | IC50 33.8 μg/ml [3] | ? | ? |
UGT1A6
Inhibitors | Strength | Dosage | Verified in Man |
---|---|---|---|
Andrographis paniculata | 50% [11] | IC50 5.66 microg/mL | ? |
Celastrol | 99% inhibition[7] | 100 μM | ? |
Isoliquiritigenin (in licorice) | 78.9% [8] | 100 μM | ? |
Milk thistle (contains silybin & silymarin) | IC50 59.5 μg/ml [3] | ? | ? |
Saw palmetto | IC50 >100 μg/ml [3] | ? | ? |
Silybin | IC50 28 µM [6] | ? | ? |
Silymarin [6] | ? | ? | ? |
Valerian root | 75% inhibition [2]1 | ? | ? |
UGT1A7
Inhibitors | Strength | Dosage | Verified in Man |
---|---|---|---|
Andrographis paniculata | 50% [11] | IC50 9.88 microg/mL | ? |
Isoliquiritigenin (in licorice) | 87.2% [8] | 100 μM | ? |
UGT1A8
Inhibitors | Strength | Dosage | Verified in Man |
---|---|---|---|
Andrographis paniculata | 50% [11] | IC50 2.57 microg/mL | ? |
Isoliquiritigenin (in licorice) | 67.2% [8] | 100 μM | ? |
UGT1A9
Inhibitors | Strength | Dosage | Verified in Man |
---|---|---|---|
Genistein (in Kudzu) | 79.5% Inhibition [12] | 30 μM | ? |
Isoliquiritigenin (in licorice) | 94.8% [8] | 100 μM | ? |
Liquiritigenin (in licorice) | K(i) 3.2 μM [9] | ? | ? |
Milk thistle (contains silybin & silymarin) | IC50 33.6 μg/ml [3] | ? | ? |
Cranberry | IC50 >100 μg/ml [3] | ? | ? |
Silybin | IC50 20 µM [6] | ? | ? |
Silymarin [6] | ? | ? | ? |
Valerian root | 75% inhibition [2]2 | ? | ? |
Inducers | Strength | Dosage | Verified in Man |
---|---|---|---|
Carbamazepine | ? | ? | ? |
Nicotine | ? | ? | ? |
UGT1A10
Inhibitors | Strength | Dosage | Verified in Man |
---|---|---|---|
Andrographis paniculata | 50% [11] | IC50 15.66 microg/mL | ? |
Isoliquiritigenin (in licorice) | 91.7% [8] | 100 μM | ? |
UGT2B4
Inhibitors | Strength | Dosage | Verified in Man |
---|---|---|---|
Methadone | ? | ? | Yes[4] |
UGT2B7
Inhibitors | Strength | Dosage | Verified in Man |
---|---|---|---|
Andrographis paniculata | 50% [11] | IC50 2.82 microg/mL | ? |
Atovaquone | ? | ? | ? |
(±) Borneol (rosemary essential oil) | IC50=200 μM3[13] | ? | ? |
(-) Borneol | IC50=200 μM4[13] | ? | ? |
Celastrol | 98% inhibition[7] | 100 μM | ? |
Dextropropoxyphene | ? | ? | Yes[5] |
Eugenol | 54.5% inhibition [1] | 100 μM | ? |
Fluconazole | ? | ? | Yes[5] |
Genistein (in Kudzu) | 30% Inhibition [12] | 30 μM | ? |
Glycyrrhetinic acid (in licorice) | K(i) 1.7 μM [10] | ? | ? |
(±) Isoborneol (in mango ginger root essential oil) | IC50=366 μM5[13] | ? | ? |
(+) Isomenthol | IC50=100 μM or less[13] | ? | ? |
Ketoconazole | ? | ? | Yes[5] |
Milk thistle (contains silybin) [6] | ? | ? | ? |
Silybin | IC50 92 µM [6] | ? | ? |
Stevioside (a sweetener found in stevia) | Potential competitive inhibition6 | ? | ? |
Valerenic acid | IC50 4.96 mM [2] | ? | ? |
Valerian root | 84% inhibition [2] | ? | ? |
Methadone | ? | ? | Yes[4][5] |
UGT2B15
Inhibitors | Strength | Dosage | Verified in Man |
---|---|---|---|
Silybin | IC50 75 µM [6] | ? | ? |
Bibliography
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