Protein Information

Name UGT1A1
Synonyms Bilirubin specific UDPGT isozyme 1; UGT 1; UGT1; GNT1; HUG BR1; Phenol/billirubinUDP glucuronosyltransferase 1; UDP glycosyltransferase 1 family polypeptide A1; UDP glucuronosyl transferase 1A1…

Compound Information

Name 1-naphthol
CAS 1-naphthalenol

Reference List

PubMed Abstract RScore(About this table)
12051676 Dean B, Chang S, Stevens J, Thomas PE, King C: Isolation and characterization of a UDP-glucuronosyltransferase (UGT1A01) cloned from female rhesus monkey. Arch Biochem Biophys. 2002 Jun 15;402(2):289-95.

Catalytic activity of UGT1A01 was determined with 7-hydroxy-4-(trifluoromethyl)-coumarin and more specific human UGT1A1 substrates (1-naphthol, beta-estradiol, 17 alpha-ethinylestradiol, and bilirubin).
83(1,1,1,3) Details
20145913 Donato MT, Montero S, Castell JV, Gomez-Lechon MJ, Lahoz A: Validated assay for studying activity profiles of human liver UGTs after drug exposure: inhibition and induction studies. Anal Bioanal Chem. 2010 Mar;396(6):2251-63. Epub 2010 Feb 10.

The assays are based on analysis and quantification by high-performance liquid chromatography-tandem mass spectrometry of glucuronides formed from selective probe substrates, namely, beta-estradiol (UGT1A1, 3-glucuronide), 1-naphthol (UGT1A6), propofol (UGT1A9), and naloxone (UGT2B7).
83(1,1,1,3) Details
17998297 Fujiwara R, Nakajima M, Yamanaka H, Katoh M, Yokoi T: Product inhibition of UDP-glucuronosyltransferase (UGT) enzymes by UDP obfuscates the inhibitory effects of UGT substrates. Drug Metab Dispos. 2008 Feb;36(2):361-7. Epub 2007 Nov 12.

In the present study, we found that UGT1A1-catalyzed estradiol 3-O-glucuronide formation and UGT1A4-catalyzed imipramine N-glucuronide formation in human liver microsomes were prominently decreased in the presence of 1-naphthol, but those by recombinant human UGT1A1 and UGT1A4, respectively, were not.
70(0,2,3,5) Details
19487247 Kerdpin O, Mackenzie PI, Bowalgaha K, Finel M, Miners JO: Influence of N-terminal domain histidine and proline residues on the substrate selectivities of human UDP-glucuronosyltransferase 1A1, 1A6, 1A9, 2B7, and 2B10. Drug Metab Dispos. 2009 Sep;37(9):1948-55. Epub 2009 Jun 1.


The conserved N-terminal domain histidine of UGT1A1, UGT1A6, UGT1A9, and UGT2B7 was mutated to proline and leucine 34 of UGT2B10 was substituted with histidine, and the capacity of the wild-type and mutant proteins to glucuronidate 4MU, 1NP, LTG, TFP, and naproxen was characterized.
4(0,0,0,4) Details
18004206 Udomuksorn W, Elliot DJ, Lewis BC, Mackenzie PI, Yoovathaworn K, Miners JO: Influence of mutations associated with Gilbert and Crigler-Najjar type II syndromes on the glucuronidation kinetics of bilirubin and other UDP-glucuronosyltransferase 1A substrates. Pharmacogenet Genomics. 2007 Dec;17(12):1017-29.


OBJECTIVES: UGT1A1 coding region mutations, including UGT1A1*6 (G71R), UGT1A1*7 (Y486D), UGT1A1*27 (P229Q) and UGT1A1*62 (F83L), have been linked to Gilbert syndrome in Asian populations, whereas homozygosity for UGT1A1*7 is associated with the Crigler-Najjar syndrome type II.
4(0,0,0,4) Details
17301691 Kurkela M, Patana AS, Mackenzie PI, Court MH, Tate CG, Hirvonen J, Goldman A, Finel M: Interactions with other human UDP-glucuronosyltransferases attenuate the consequences of the Y485D mutation on the activity and substrate affinity of UGT1A6. Pharmacogenet Genomics. 2007 Feb;17(2):115-26.

Using 1-naphthol as the aglycone substrate, the Km of 6YD for the cosubstrate UDP-glucuronic acid was about 50 times higher than in UGT1A6.
OBJECTIVES: To explore the possible role of hetero-oligomerization among the human UDP-glucuronosyltransferases in attenuating the consequences of the pathological Y486D mutation (UGT1A1 numbering) that often causes hyperbilirubinaemia.
3(0,0,0,3) Details
16819192 Naganuma M, Saruwatari A, Okamura S, Tamura H: Turmeric and curcumin modulate the conjugation of 1-naphthol in Caco-2 cells. Biol Pharm Bull. 2006 Jul;29(7):1476-9.

Moreover, and in contrast to the moderate inhibition of UGT activity by turmeric and curcumin, both induce the expression of the UGT1A1 and UGT1A6 genes, revealed by real-time PCR analysis.
1(0,0,0,1) Details
17618724 Lee CH, Ito Y, Yanagiba Y, Yamanoshita O, Kim H, Zhang SY, Kamijima M, Gonzalez FJ, Nakajima T: Pyrene-induced CYP1A2 and SULT1A1 may be regulated by CAR and not by AhR. . Toxicology. 2007 Sep 5;238(2-3):147-56. Epub 2007 Jun 2.


In contrast, pyrene exposure increased expression of the UGT1A1 and 1A6, and glucuronidation activities associated with 1-hydroxypyrene and 1-naphthol in the liver only in AhR (-/-) mice, although pyrene treatment dose-dependently decreased the latter activity.
1(0,0,0,1) Details
12153725 Yokota H, Kunimasa Y, Shimoyama Y, Kobayashi T, Matsumoto J, Yuasa A: Effects on extrahepatic UDP-glucuronosyltransferases in hypophysectomized rat. J Biochem. 2002 Aug;132(2):265-70.

UDP-glucuronosyltransferase activities toward 1-naphthol decreased to 20-30% of control in the liver, kidney, lung, and testis.
The mRNA of UGT1A1, which is an isoform contributing to the glucuronidation of bilirubin, increased significantly in the liver and slightly in the kidney after hypophysectomy.
1(0,0,0,1) Details
15980103 Tochigi Y, Yamashiki N, Ohgiya S, Ganaha S, Yokota H: Isoform-specific expression and induction of udp-glucuronosyltransferase in immunoactivated peritoneal macrophages of the rat. Drug Metab Dispos. 2005 Sep;33(9):1391-8. Epub 2005 Jun 24.

Expressions of UGT1A1, 1A6, and 1A7 were observed in macrophages by immunohistochemical staining and reverse transcriptase-polymerase chain reaction.
When macrophage cells cultured in plates were exposed to 1-naphthol and 3-hydroxybenzo-[a] pyrene (3-OH-B [a] P), these glucuronides increased in the medium, indicating that macrophages glucuronidated the chemicals.
1(0,0,0,1) Details
15684482 Okamura S, Suzuki K, Yanase M, Koizumi M, Tamura HO: The effects of coffee on conjugation reactions in human colon carcinoma cells. Biol Pharm Bull. 2005 Feb;28(2):271-4.


After supplementing Caco-2 cultures with both 1-naphthol (200 microM) and various concentrations of coffee, the accumulation of 1-naphthyl sulfate and glucuronide in the growth medium was determined by analytical HPLC over a 24-h period.
0(0,0,0,0) Details
12814968 Chen C, Staudinger JL, Klaassen CD: Nuclear receptor, pregname X receptor, is required for induction of UDP-glucuronosyltranferases in mouse liver by pregnenolone-16 alpha-carbonitrile. Drug Metab Dispos. 2003 Jul;31(7):908-15.


In wild-type mice, PCN treatment significantly increased UGT activities toward bilirubin, 1-naphthol, chloramphenicol, thyroxine, and triiodothyronine.
0(0,0,0,0) Details