胆红素作为人体的一种重要内源性物质,是临床诊断黄疸的主要依据,也是肝功能的重要指标。本文在简述胆红素代谢过程、代谢动力学及代谢异常的基础上,重点对有机阴离子转运多肽(organic anion transport polypeptide.OATP)和多药耐药相...胆红素作为人体的一种重要内源性物质,是临床诊断黄疸的主要依据,也是肝功能的重要指标。本文在简述胆红素代谢过程、代谢动力学及代谢异常的基础上,重点对有机阴离子转运多肽(organic anion transport polypeptide.OATP)和多药耐药相关蛋白(multidrug-associated protein.MRP)等转运体介导的胆红素转运、PXR和CAR等核受体对UGTlAl介导的胆红素代谢调控、药物对胆红素代谢的抑制和诱导,及其与胆红素相关病症关系等方面的最新进展进行归纳和总结,为进一步研究和揭示黄疸、高胆红素血症、新生儿黄疸等胆红素相关病症的发生原因和发生机制提供参考,并为其诊断、预防和治疗提供最新科学依据。展开更多
AIM： To identify the variants in U rase 1 （UGT1A1） gene in Gilbert＇s syndrome （GS） and to estimate the association between homozygosity for TA insertion and GS in India, as well as the frequency of TA insertion ...AIM： To identify the variants in U rase 1 （UGT1A1） gene in Gilbert＇s syndrome （GS） and to estimate the association between homozygosity for TA insertion and GS in India, as well as the frequency of TA insertion and its impact among normal controls in India. METHODS： Ninety-five GS cases and 95 normal controls were selected. Liver function and other tests were done. The promoter and all 5 exons of UGT1A1 gene were resequenced. Functional assessment of a novel trinucleotide insertion was done by in silico analysis and by estimating UGT1A1 promoter activity carried out by ludferase reporter assay of appropriate constructs in Hep G2 cell line. RESULTS： Among the GS patients, 80% were homozygous for the TA insertion, which was several-fold higher than reports from other ethnic groups. The mean UCB level was elevated among individuals with only one copy of this insertion, which was not significantly different from those with two copies. Many new DNA variants in UGT1A1 gene were discovered, including a trinucleotide （CAT） insertion in the promoter found in a subset （10%） of GS patients, but not among normal controls. In-silico analysis showed marked changes in the DNA-folding of the promoter and functional analysis showed a 20-fold reduction in transcription efficiency of UGT1A1 gene resulting from this insertion, thereby significantly elevating the UCB level. CONCLUSION： The genetic epidemiology of GS is variable across ethnic interactions among UGT1A1 groups and the epistatic promoter variants modulate bilirubin glucuronidation.展开更多
Bilirubin,a major end product of heme breakdown,is an important constituent of bile,responsible for its characteristic colour.Over recent decades,our understanding of bilirubin metabolism has expanded along with the p...Bilirubin,a major end product of heme breakdown,is an important constituent of bile,responsible for its characteristic colour.Over recent decades,our understanding of bilirubin metabolism has expanded along with the processes of elimination of other endogenous and exogenous anionic substrates,mediated by the action of multiple transport systems at the sinusoidal and canalicular membrane of hepatocytes.Several inherited disorders characterised by impaired bilirubin conjugation(Crigler-Najjar syndrome typeⅠand typeⅡ,Gilbert syndrome)or transport(Dubin-Johnson and Rotor syndrome)result in various degrees of hyperbilirubinemia of either the predominantly unconjugated or predominantly conjugated type.Moreover,disrupted regulation of hepatobiliary transport systems can explain jaundice in many acquired liver disorders.In this review,we discuss the recent data on liver bilirubin handling based on the discovery of the molecular basis of Rotor syndrome.The data show that a substantial fraction of bilirubin conjugates is primarily secreted by MRP3 at the sinusoidal membrane into the blood,from where they are subsequently reuptaken by sinusoidal membrane-bound organic anion transporting polypeptides OATP1B1 and OATP1B3.OATP1B proteins are also responsible for liver clearance of bilirubin conjugated in splanchnic organs,such as the intestine and kidney,and for a number of endogenous compounds,xenobiotics and drugs.Absence of one or both OATP1B proteins thus may have serious impact on toxicity of commonly used drugs cleared by this system such as statins,sartans,methotrexate or rifampicin.The liverblood cycling of conjugated bilirubin is impaired in cholestatic and parenchymal liver diseases and this impairment most likely contributes to jaundice accompanying these disorders.展开更多
Uridine-diphosphate glucuronosyltransferase 1 A1(UGT1 A1) is an important conjugative enzyme in mammals that is responsible for the conjugation and detoxification of both endogenous and xenobiotic compounds. Strong in...Uridine-diphosphate glucuronosyltransferase 1 A1(UGT1 A1) is an important conjugative enzyme in mammals that is responsible for the conjugation and detoxification of both endogenous and xenobiotic compounds. Strong inhibition of UGT1 A1 may trigger adverse drug/herb–drug interactions, or result in metabolic disorders of endobiotic metabolism. Therefore, both the US Food and Drug Administration(FDA)and the European Medicines Agency(EMA) have recommended assaying the inhibitory potential of drugs under development on the human UGT1 A1 prior to approval. This review focuses on the significance,progress and challenges in discovery and characterization of UGT1 A1 inhibitors. Recent advances in the development of UGT1 A1 probes and their application for screening UGT1 A1 inhibitors are summarized and discussed in this review for the first time. Furthermore, a long list of UGT1 A1 inhibitors, including information on their inhibition potency, inhibition mode, and affinity, has been prepared and analyzed. Challenges and future directions in this field are highlighted in the final section. The information and knowledge that are presented in this review provide guidance for rational use of drugs/herbs in order to avoid the occurrence of adverse effects via UGT1 A1 inhibition, as well as presenting methods for rapid screening and characterization of UGT1 A1 inhibitors and for facilitating investigations on UGT1 A1–ligand interactions.展开更多
AIM: To investigate the relationship between single nucleotide polymorphisms in the uridine-diphosphoglucurono-syltransferase (UGT) UGT1A7 and UGT1A1 genes and patients suffering from colorectal cancer (CRC). METHODS:...AIM: To investigate the relationship between single nucleotide polymorphisms in the uridine-diphosphoglucurono-syltransferase (UGT) UGT1A7 and UGT1A1 genes and patients suffering from colorectal cancer (CRC). METHODS: A case-control study was designed in order to investigate the genotypes of the UGT1A7 and UGT1A1 genes, which were identified by the polymerase chain reaction-restriction fragment length polymorphism (RFLP) method, for 268 CRC patients and 441 healthy controls. RESULTS: The results of simple logistical regressions revealed odds ratios (ORs) of 1.97 (P<0.001),1.91 (P<0.001),and 2.03 (P<0.001) for patients who carried the UGT1A7*1/*3 genotype,UGT1A7*3 allele,and variant-211 UGT1A1 allele.The interaction of UGT1A7*3 allele and variant-211 UGT1A1 allele produced an additive effect on the risk for the development of CRC [observed OR (2.34) greater than expected OR (1.59)]. For the 268 patients, the results of simple logistical regressions indicated that the OR of developing metastases was 4.90 (P<0.001) and 4.89 (P<0.001) for the individuals possessing UGT1A7*3 allele and variant-211 UGT1A1 allele, respectively. The results of multivariate logistical regressions confirmed these findings (OR = 2.51, P= 0.01; and OR=2.71,P=0.01,respectively).The interaction of these two variants resulted in an additive effect on the risk for metastases amongst patients [observed OR (6.83) greater than expected OR (4.56)]. CONCLUSION: In conclusion, carriage of the UGT1A7*3 allele, as well as variant-211 UGT1A1 allele represents a risk factor for the development of, and a determinant for, metastases associated with CRC patients.展开更多
文摘胆红素作为人体的一种重要内源性物质,是临床诊断黄疸的主要依据,也是肝功能的重要指标。本文在简述胆红素代谢过程、代谢动力学及代谢异常的基础上,重点对有机阴离子转运多肽(organic anion transport polypeptide.OATP)和多药耐药相关蛋白(multidrug-associated protein.MRP)等转运体介导的胆红素转运、PXR和CAR等核受体对UGTlAl介导的胆红素代谢调控、药物对胆红素代谢的抑制和诱导,及其与胆红素相关病症关系等方面的最新进展进行归纳和总结,为进一步研究和揭示黄疸、高胆红素血症、新生儿黄疸等胆红素相关病症的发生原因和发生机制提供参考,并为其诊断、预防和治疗提供最新科学依据。
基金Supported by grants from the Department of Biotechnology, Government of India (to PPM) and the Department of Science & Technology, Government of West Bengal (to AC)
文摘AIM： To identify the variants in U rase 1 （UGT1A1） gene in Gilbert＇s syndrome （GS） and to estimate the association between homozygosity for TA insertion and GS in India, as well as the frequency of TA insertion and its impact among normal controls in India. METHODS： Ninety-five GS cases and 95 normal controls were selected. Liver function and other tests were done. The promoter and all 5 exons of UGT1A1 gene were resequenced. Functional assessment of a novel trinucleotide insertion was done by in silico analysis and by estimating UGT1A1 promoter activity carried out by ludferase reporter assay of appropriate constructs in Hep G2 cell line. RESULTS： Among the GS patients, 80% were homozygous for the TA insertion, which was several-fold higher than reports from other ethnic groups. The mean UCB level was elevated among individuals with only one copy of this insertion, which was not significantly different from those with two copies. Many new DNA variants in UGT1A1 gene were discovered, including a trinucleotide （CAT） insertion in the promoter found in a subset （10%） of GS patients, but not among normal controls. In-silico analysis showed marked changes in the DNA-folding of the promoter and functional analysis showed a 20-fold reduction in transcription efficiency of UGT1A1 gene resulting from this insertion, thereby significantly elevating the UCB level. CONCLUSION： The genetic epidemiology of GS is variable across ethnic interactions among UGT1A1 groups and the epistatic promoter variants modulate bilirubin glucuronidation.
基金Supported by The Project(Ministry of Health,Czech Republic)for Development of Research Organization 00023001(IKEM,Prague,Czech Republic),Institutional support
文摘Bilirubin,a major end product of heme breakdown,is an important constituent of bile,responsible for its characteristic colour.Over recent decades,our understanding of bilirubin metabolism has expanded along with the processes of elimination of other endogenous and exogenous anionic substrates,mediated by the action of multiple transport systems at the sinusoidal and canalicular membrane of hepatocytes.Several inherited disorders characterised by impaired bilirubin conjugation(Crigler-Najjar syndrome typeⅠand typeⅡ,Gilbert syndrome)or transport(Dubin-Johnson and Rotor syndrome)result in various degrees of hyperbilirubinemia of either the predominantly unconjugated or predominantly conjugated type.Moreover,disrupted regulation of hepatobiliary transport systems can explain jaundice in many acquired liver disorders.In this review,we discuss the recent data on liver bilirubin handling based on the discovery of the molecular basis of Rotor syndrome.The data show that a substantial fraction of bilirubin conjugates is primarily secreted by MRP3 at the sinusoidal membrane into the blood,from where they are subsequently reuptaken by sinusoidal membrane-bound organic anion transporting polypeptides OATP1B1 and OATP1B3.OATP1B proteins are also responsible for liver clearance of bilirubin conjugated in splanchnic organs,such as the intestine and kidney,and for a number of endogenous compounds,xenobiotics and drugs.Absence of one or both OATP1B proteins thus may have serious impact on toxicity of commonly used drugs cleared by this system such as statins,sartans,methotrexate or rifampicin.The liverblood cycling of conjugated bilirubin is impaired in cholestatic and parenchymal liver diseases and this impairment most likely contributes to jaundice accompanying these disorders.
基金supported by the NSF of China(81773687,81703606,81573501,81473181)the National Key Research and Development Program of China(2017YFC1700200 and2017YFC1702000)+4 种基金the Fundamental Research Funds for the Central Universities(wd01185)the National S&T Major Projects of China(2017ZX09101004)Program of Shanghai Academic/Technology Research Leader(18XD1403600)the Innovative Entrepreneurship Program of High-level Talents in Dalian(2016RQ025&2017RQ121)the Doctoral Scientific Research Foundation of Liaoning Province,China(20170520059)
文摘Uridine-diphosphate glucuronosyltransferase 1 A1(UGT1 A1) is an important conjugative enzyme in mammals that is responsible for the conjugation and detoxification of both endogenous and xenobiotic compounds. Strong inhibition of UGT1 A1 may trigger adverse drug/herb–drug interactions, or result in metabolic disorders of endobiotic metabolism. Therefore, both the US Food and Drug Administration(FDA)and the European Medicines Agency(EMA) have recommended assaying the inhibitory potential of drugs under development on the human UGT1 A1 prior to approval. This review focuses on the significance,progress and challenges in discovery and characterization of UGT1 A1 inhibitors. Recent advances in the development of UGT1 A1 probes and their application for screening UGT1 A1 inhibitors are summarized and discussed in this review for the first time. Furthermore, a long list of UGT1 A1 inhibitors, including information on their inhibition potency, inhibition mode, and affinity, has been prepared and analyzed. Challenges and future directions in this field are highlighted in the final section. The information and knowledge that are presented in this review provide guidance for rational use of drugs/herbs in order to avoid the occurrence of adverse effects via UGT1 A1 inhibition, as well as presenting methods for rapid screening and characterization of UGT1 A1 inhibitors and for facilitating investigations on UGT1 A1–ligand interactions.
基金Supported by a Grant From the National Science Council (NSC 93-3112-B-242-001), Taipei, Taiwan, China
文摘AIM: To investigate the relationship between single nucleotide polymorphisms in the uridine-diphosphoglucurono-syltransferase (UGT) UGT1A7 and UGT1A1 genes and patients suffering from colorectal cancer (CRC). METHODS: A case-control study was designed in order to investigate the genotypes of the UGT1A7 and UGT1A1 genes, which were identified by the polymerase chain reaction-restriction fragment length polymorphism (RFLP) method, for 268 CRC patients and 441 healthy controls. RESULTS: The results of simple logistical regressions revealed odds ratios (ORs) of 1.97 (P<0.001),1.91 (P<0.001),and 2.03 (P<0.001) for patients who carried the UGT1A7*1/*3 genotype,UGT1A7*3 allele,and variant-211 UGT1A1 allele.The interaction of UGT1A7*3 allele and variant-211 UGT1A1 allele produced an additive effect on the risk for the development of CRC [observed OR (2.34) greater than expected OR (1.59)]. For the 268 patients, the results of simple logistical regressions indicated that the OR of developing metastases was 4.90 (P<0.001) and 4.89 (P<0.001) for the individuals possessing UGT1A7*3 allele and variant-211 UGT1A1 allele, respectively. The results of multivariate logistical regressions confirmed these findings (OR = 2.51, P= 0.01; and OR=2.71,P=0.01,respectively).The interaction of these two variants resulted in an additive effect on the risk for metastases amongst patients [observed OR (6.83) greater than expected OR (4.56)]. CONCLUSION: In conclusion, carriage of the UGT1A7*3 allele, as well as variant-211 UGT1A1 allele represents a risk factor for the development of, and a determinant for, metastases associated with CRC patients.
