Uridine Diphosphate Glucuronosyltransferase 1A1 Research Articles

Choline supplementation prevents the effects of bilirubin on cerebellar-mediated behavior in choline-restricted Gunn rat pups.

Background:Bilirubin is produced by the breakdown of hemoglobin, and is normally catabolized and excreted. Neurotoxic accumulation of serum bilirubin often occurs in premature infants. The homozygous Gunn rat lacks uridine diphosphate-glucuronosyltransferase-1A1 (UGT1A1), the enzyme needed to biotransform bilirubin. This rodent model of hyperbilirubinemia emulates many aspects of bilirubin toxicity observed in the human infant. We demonstrate that choline supplementation in early postnatal development is neuroprotective in the choline restricted Gunn rat, when hyperbilirubinemia is induced on postnatal day 5.Methods:We first compared behaviors and cerebellar weight of pups born to dams consuming regular rat chow to those of dams consuming choline-restricted diets. Secondly, we measured behaviors and cerebellar weights of pups born to choline-restricted dams, reared on a choline-restricted diet, supplemented with or without choline and treated with or without sulfadimethoxine (SDMX).Results:A choline-restricted diet did not change the behavioral outcomes, but cerebellar weight was reduced in the choline-restricted group regardless of genotype or SDMX administration. SDMX induced behavioral deficits in jj pups, and choline supplementation improved most behavioral effects and cerebellar weight in SDMX-treated jj rats.Conclusion:These results suggest that choline may be used as a safe and effective neuroprotective intervention against hyperbilirubinemia in the choline deficient premature infant.

Relation of Uridine Diphosphate Glucuronosyltransferase 1A1 Promoter Gene Polymorphism (211G>A) With Risk of Hyperbilirubinemia in Neonates

Background: The gene 211G>A variants, that underlie complex disorders, are characteristically common in the neonatal hyperbilirubinemia. However, it is the contribution of multiple different co-expressed susceptibility genes that individually confer a small increase in risk coupled with environmental factors that generate complex disorder phenotypes. Objective: This study aimed to understand the relation of 211G>A promoter polymorphism in UGT1A1 gene and the risk of hyperbilirubinemia in newborns. Patients and Methods: The study included 50 newborns with hyperbilirubinemia with gestation age of ≥ 37weeks and postnatal age of ≤ 2 weeks with normal birth weight. 34 were males and 16 were females. They were divided into two groups; case group consisting of 30 neonates with the peak of total serum bilirubin (TSB) levels ≥ 16 mg /dl and control group consisting of 20 neonates with the peak total serum bilirubin (TSB) levels A genotype can be used as a novel method to detect susceptibility to indirect hyperbilirubinemia in neonates. Conclusion: Our findings added to the understanding of the significance of UGT1A1 in association with neonatal hyperbilirubinemia in East Delta of Egyptian population. Additionally we are in need for other studies to investigate the protective mechanisms.

Relation of Uridine Diphosphate Glucuronosyltransferase 1A1 Promoter Gene Polymorphism (211G>A) With Risk of Hyperbilirubinemia in Neonates

Background: The gene 211G>A variants, that underlie complex disorders, are characteristically common in the neonatal hyperbilirubinemia. However, it is the contribution of multiple different co-expressed susceptibility genes that individually confer a small increase in risk coupled with environmental factors that generate complex disorder phenotypes. Objective: This study aimed to understand the relation of 211G>A promoter polymorphism in UGT1A1 gene and the risk of hyperbilirubinemia in newborns. Patients and Methods: The study included 50 newborns with hyperbilirubinemia with gestation age of ≥ 37weeks and postnatal age of ≤ 2 weeks with normal birth weight. 34 were males and 16 were females. They were divided into two groups; case group consisting of 30 neonates with the peak of total serum bilirubin (TSB) levels ≥ 16 mg /dl and control group consisting of 20 neonates with the peak total serum bilirubin (TSB) levels A genotype can be used as a novel method to detect susceptibility to indirect hyperbilirubinemia in neonates. Conclusion: Our findings added to the understanding of the significance of UGT1A1 in association with neonatal hyperbilirubinemia in East Delta of Egyptian population. Additionally we are in need for other studies to investigate the protective mechanisms.

Effect of Genetic Polymorphisms on the Pharmacokinetics of Deferasirox in Healthy Chinese Subjects and an Artificial Neural Networks Model for Pharmacokinetic Prediction.

Deferasirox is an oral iron chelator used to reduce iron levels in iron-overloaded patients with transfusion-dependent anemia or non-transfusion-dependent thalassemia. This study investigated the effects of genetic polymorphisms on the pharmacokinetics of deferasirox in healthy Chinese subjects and constructed a pharmacokinetic prediction model based on physiologic factors and genetic polymorphism data. Twenty-eight subjects were enrolled in a randomized, open-label, two-period crossover study, and they received a single dose of one of two formulations of deferasirox (20mg/kg) with a 7-day washout interval between the two periods. The plasma defersirox concentration was determined using a validated liquid chromatography-tandem mass spectrometry method, and pharmacokinetic parameters were calculated using the noncompartmental method. The polymorphisms of uridine diphosphate glucuronosyltransferase 1A1 (UGT1A1), UGT1A3, multidrug resistance protein 2 (MRP2), cytochrome P450 1A1(CYP1A1), and breast cancer resistance protein 1 (BCRP1) were genotyped using Sanger sequencing. A back-propagation artificial neural network (BP-ANN) model was used to predict the pharmacokinetics. The UGT1A1 rs887829 C > T single-nucleotide polymorphism (SNP) significantly influenced the area under the plasma concentration-time curve and the terminal half-life. Neither the MRP2 rs2273697 G > A SNP nor BCRP1 rs2231142 G > T SNP altered the absorption, disposition, and excretion of the drug. The BP-ANN model had a high goodness-of-fit index and good coherence between the predicted and measured concentrations (R2 = 0.921). Metabolic enzyme-related genetic polymorphisms were more strongly associated with the pharmacokinetics of deferasirox than membrane transporter-related genetic polymorphisms in the Chinese population. www.Chinadrugtrials.org.cn CTR20191164.

Metabolism and Pharmacokinetic Drug-Drug Interaction Profile of Vericiguat, A Soluble Guanylate Cyclase Stimulator: Results From Preclinical and Phase I Healthy Volunteer Studies.

BackgroundVericiguat is a stimulator of soluble guanylate cyclase currently under investigation as a first-in-class therapy for worsening chronic heart failure (NCT02861534). Patients with heart failure often require polypharmacy because of comorbidities. Hence, understanding the clearance mechanisms, elimination, and potential for pharmacokinetic drug–drug interactions of vericiguat is important for dose recommendations in this patient population.MethodsBiotransformation and perpetrator properties of vericiguat were characterized in vitro using human hepatocytes, liver microsomes, and recombinant enzymes. This was complemented by a human mass balance study and ten drug–drug interaction studies in healthy volunteers wherein vericiguat was co-administered orally with omeprazole, magnesium/aluminum hydroxide, ketoconazole, rifampicin, mefenamic acid, midazolam, warfarin, digoxin, sacubitril/valsartan, aspirin, or sildenafil.ResultsIn the human mass balance study, mean total radioactivity recovered was 98.3% of the dose administered (53.1% and 45.2% excreted via urine and feces, respectively). The main metabolic pathway of vericiguat is glucuronidation via uridine diphosphate-glucuronosyltransferase 1A9 and 1A1. In vitro studies revealed a low risk of vericiguat acting as a perpetrator by inhibiting cytochrome P450s, uridine diphosphate-glucuronosyltransferase isoforms, or major transport proteins, or by inducing cytochrome P450s. These observations were supported by phase I drug–drug interaction studies. Phase I studies that assessed the propensity of vericiguat as a victim drug showed changes in the range that did not warrant recommendations for dose adjustment in phase III.ConclusionsA low pharmacokinetic interaction potential of vericiguat was estimated from in vitro data and confirmed in vivo. Thus, vericiguat is suitable for a patient population with multiple comorbidities requiring polypharmacy.Electronic supplementary materialThe online version of this article (10.1007/s40262-020-00895-x) contains supplementary material, which is available to authorized users.

Efficacy and safety of Shengjiang Xiexin decoction in prophylaxis of chemotherapy-related diarrhea in small cell lung cancer patients: study protocol for a multicenter randomized controlled trial

BackgroundDiarrhea is a common adverse reaction in patients with cancer receiving chemotherapy, for which there is currently no effective method of treatment. Shengjiang Xiexin decoction (SXD), a classic traditional Chinese medicine (TCM) formula, has shown efficacy in alleviating irinotecan-induced diarrhea in preliminary clinical studies. The current study is designed to assess the efficacy and safety of SXD for prophylaxis against irinotecan-induced diarrhea. Additionally, we employ a new approach to analyze and evaluate the data based on the patients’ uridine diphosphate glucuronosyltransferase 1A1 (UGT1A1) genotype, which predicts the risk of diarrhea.Methods and designA prospective, double-blind, randomized, placebo-controlled trial will be conducted in patients with small cell lung cancer (SCLC) from five hospitals in China. For this study, 100 irinotecan-naïve patients will be randomly allocated to either the SXD or placebo arms in a 1:1 ratio. Stratified randomization will be used to divide subjects by UGT1A1 genotype into groups with differing risk of diarrhea. The trial will consist of two cycles of chemotherapy with 14 days of oral administration of SXD or placebo administered beginning between 3 days before and up to 11 days after initiation of each chemotherapy cycle. The primary study outcome is the incidence of diarrhea. Secondary outcomes include the degree of diarrhea, the degree of neutropenia, the rate of alterations in chemotherapy regimens, the amount of antidiarrheal drug taken, the rate of hospitalization, and evaluation of chemotherapy efficacy.DiscussionThis study is the first to use the UGT1A1 genotype to stratify patients into groups based on their risk of diarrhea, and to provide a complete assessment of chemotherapy-related diarrhea (CRD), including records of diarrhea duration, grading the severity of diarrhea, and evaluating concomitant symptoms. Study results will provide high-level clinical evidence on the use of SXD as prophylaxis for CRD.Trial registrationChinese Clinical Trial Register: ChiCTR1800018490. Registered on 20 September 2018. Retrospectively registered. http://www.chictr.org.cn/edit.aspx?pid=25250&htm=4c

Neonatal Buccal Cell Collection: A Non-Invasive Strategy to Provide A Reliable Source of DNA for High Resolution Melting Analysis

Background: The low yield and quality of buccal-derived genomic DNA have reduced its applicability in various genetic research. The aim of this study was to assess the quantity, purity and genotyping efficiency of genomic DNA isolated from neonatal buccal swabs. Methods: Paired buccal swabs and whole blood samples were collected from 60 neonates with the mean age 5 days (SD=1.57). The genomic DNA quantity and purity were measured by using Infinite® 200 PRO NanoQuant reader and agarose gel electrophoresis. High-resolution melting (HRM) analysis was used to analyse the sequence variants present in uridine diphosphate glucuronosyltransferase 1A1 (UGT1A1 c.211G>A) and nuclear receptor subfamily 1, group I, member 3 (NR1I3 IVS8+116T>G) genes. Results: Buccal swabs provided lower mean genomic DNA concentration (18.78 ± 8.39 ng/µl versus 40.02 ± 13.03 ng/µl), yield (2.63 ± 1.17 µg versus 8.00 ± 2.61 µg). The purity of buccal samples however were inconsistent with 16 samples (26.7%) having A260/280 ratios below 1.8 which indicated protein contamination. Genomic DNA purity for all blood samples were within the ideal range with average absorbance ratios of 1.8−2.0. However, all buccal genomic DNA demonstrated 100% genotype call rates for all variants. A complete genotype concordance was also observed between paired genomic DNA samples. Conclusion: Despite related to a reduced quantity and purity, neonatal buccal genomic DNA could generate reliable HRM genotyping results. Therefore, buccal swab collection is a promising alternative to the invasive blood sampling to provide genomic DNA for genetic analysis involving paediatric population.

Network Pharmacology-Based Prediction and Verification of Qingluo Tongbi Formula to Reduce Liver Toxicity of Tripterygium wilfordii via UGT2B7 in Endoplasmic Reticulum.

BackgroundThe hepatotoxicity of Tripterygium wilfordii Hook. f. (TWHF) limits its clinic utilization. Qingluo Tongbi formula (QTF) was formulated based on a basic Chinese medicine theory. Previous studies have confirmed the safety and efficacy of QTF in treating rheumatoid arthritis. Therefore, we considered that TWHF could be detoxified based on its reasonable compatibility with QTF. We investigated the detoxicity mechanism of QTF in reducing the liver toxicity of TWHF.Material/MethodsWe used network pharmacology to determine the relevant metabolism targets of TWHF, focusing on the phase II metabolic enzymes uridine diphosphate-glucuronosyltransferase 1A1 (UGT1A1), UGT1A6, and UGT2B7. Based on the molecular mechanisms of these predictions and the results of the network analysis, we designed experiments to verify our hypothesis in vivo. We used western blotting, real-time quantitative polymerase chain reaction (RT-qPCR), double immunofluorescence, and laser confocal microscopy to detect the expression of UGTs. Finally, we used transmission electron microscopy to observe the endoplasmic reticulum structure.ResultsThe results confirmed that QTF reversed the TWHF-induced reduction of UGT content in liver microsomes, upregulated UGT1A1 and UGT1A6 but not UGT2B7 in the liver tissue. UGT2B7 expression in the liver and liver microsomes was inconsistent. QTF upregulated the expression of UGT2B7 in the endoplasmic reticulum, and QTF upregulated UGT2B7 expression levels in the endoplasmic reticulum compared with TWHF, which reduced liver toxicity. Structural changes were observed in the endoplasmic reticulum.ConclusionsThe Chinese traditional medicine compound QTF can achieve the effect of detoxification by upregulating the expression of UGT2B7 in the endoplasmic reticulum.

Jiawei Xianglian Decoction (JWXLD), a Traditional Chinese Medicine (TCM), Alleviates CPT‐11‐Induced Diarrhea in Mice

Irinotecan (CPT-11) is used for therapy of various cancers. However, it has several serious adverse reactions such as diarrhea which is caused by SN-38, the active form of CPT-11. This study aimed to evaluate the effectiveness of Jiawei xianglian decoction (JWXLD), which has been widely used for the treatment of diarrhea in China. In this study, a mouse model with delayed diarrhea was generated by CPT-11. Real-time PCR and enzyme-linked immunosorbent assay (ELISA) were performed to explore intestinal microflora and inflammatory cytokine. Hematoxylin and eosin (H&E) staining was used to analyze tissue morphology. We found that 0.12, 0.23, and 0.46 g JWXLD significantly reduced the severity of CPT-11-induced diarrhea. The levels of Lactobacillus (Lacto) and Bifidobacterium (Bifid) were significantly downregulated by CPT-11, and these effects can be reversed by JWXLD treatment. Furthermore, JWXLD was observed to decrease the activity of β-glucuronidase (β-GD). Histopathological data showed that CPT-11 induced severe intestinal mucosal injury, which was characterized as grade 6, and JWXLD significantly alleviated the injury. In addition, CPT-11 increased the productions of tumor necrosis factor-alpha (TNF-α), tumor necrosis factor-beta (TNF-β), interleukin-6 (IL-6), and interleukin-1 (IL-1), but decreased interleukin-15 (IL-15), interleukin-7 (IL-7), and uridine diphosphate-glucuronosyltransferase 1A1 (UGT1A1). In conclusion, JWXLD can counteract these effects caused by CPT-11 treatment. JWXLD could alleviate CPT-11-induced diarrhea.

Regorafenib plus FOLFIRI with irinotecan dose escalated according to uridine diphosphate glucuronosyltransferase 1A1genotyping in previous treated metastatic colorectal cancer patients:study protocol for a randomized controlled trial

BackgroundRegorafenib is an oral multikinase inhibitor for metastatic colorectal cancer (mCRC) previously treated with fluoropyrimidines, irinotecan, oxaliplatin, monoclonal antibodies targeting vascular endothelial growth factor, and monoclonal antibodies targeting epidermal growth factor receptor. A dose reduction from 160 mg to 120 mg regorafenib reduces regorafenib-associated adverse events (AEs). Dose adjustment of irinotecan in a 5-fluorouracil/leucovorin/irinotecan (FOLFIRI) regimen on the basis of an individual uridine diphosphate glucuronosyl transferase 1A1 (UGT1A1) genotype provides optimal oncological outcomes with acceptable AEs. The aim of this study is to address the efficacy and safety of a dose-adjusted combination of regorafenib and FOLFIRI for patients with mCRC.MethodsA prospective, multicenter, randomized in a 2:1 ratio, controlled, clinical trial with two parallel arms will be conducted to compare irinotecan dose-escalated FOLFIRI according to UGT1A1 genotyping plus 120 mg regorafenib with 120 mg regorafenib alone in previously treated patients with mCRC. The primary endpoint is progression-free survival, and the secondary endpoints are overall survival, disease control rate, time to progression, and duration of treatment. Safety assessments will also be recorded.DiscussionDose adjustment for regorafenib and irinotecan makes treatment-related AEs tolerable and makes the concomitant treatment practicable. This study will provide initial evidence regarding the efficacy and safety of a new combination of chemotherapy and a targeted agent for mCRC.Trial registrationClinicalTrials.gov, NCT03880877. Prospectively registered on 19 March 2019.

Cytochrome P450 1A2 Is Incapable of Oxidizing Bilirubin Under Physiological Conditions.

Background: Bilirubin (BR) is metabolized mainly by uridine diphosphate (UDP)-glucuronosyltransferase 1A1 (UGT1A1) through glucuronidation in the liver. Some studies have shown that several subtypes of cytochrome P450 (CYP) enzymes, including CYP1A2, are upregulated by inducers and proposed to be alternative BR degradation enzymes. However, no information is available on the BR degradation ability of CYP in normal rats without manipulation by CYP inducers. Methods: Quantitative real-time polymerase chain reaction (QRT-PCR), western blot, immunofluorescence, and confocal microscopy were used to find expression of CYP1A2 in the brain and the liver. BR metabolites in microsomal fractions during development were examined by high-performance liquid chromatography/electrospray ionization tandem mass spectrometry (LC-MS/MS). Results: In the present study, we observed that CYP1A2 mRNA levels increased at postnatal days (P)14 and P30 with respect to the level at P7 both in liver and brain, this increment was especially pronounced in the brain at P14. The expression of CYP1A2 in the brainstem (BS) was higher than that in the cerebellum (CLL) and cortex (COR). Meanwhile, the CYP1A2 protein level was significantly higher in the COR than in the brainstem and CLL at P14. The levels of BR and its metabolites (m/z values 301, 315, 333 and biliverdin) were statistically unaltered by incubation with liver and brain microsomal fractions. Conclusion: Our results indicated that the region-specific expression of CYP1A2 increased during development, but CYP family enzymes were physiologically incapable of metabolizing BR. The ability of CYPs to oxidize BR may be triggered by CYP inducers.

Uridine diphosphate glucuronosyl transferase 1A (UGT1A1) promoter polymorphism in young patients with sickle cell anaemia: report of the first cohort study from Nigeria

Background(TA) n repeat sequence (rs8175347) of UGT1A1 gene promoter polymorphism is associated with serum bilirubin levels and gallstones among different sickle cell anaemia (SCA) populations. There are no data on UGT1A1 polymorphisms and their impact on Nigerian SCA patients. In this study, we determined the distribution of the UGT1A1 (TA) n genotypes among a group of young Nigerian SCA patients and healthy controls. In addition, the influence of UGT1A1 (TA) n genotypes on the laboratory and clinical events among the patients was determined.MethodsThe distribution of the UGT1A1 (TA) n genotypes among 101 young Nigerian SCA patients and 64 normal appropriate controls were determined and studied. The UGT1A1 (TA) n genotypes were further classified into subgroups and used to differentiate the clinical events and laboratory parameters of the patients.ResultsFour (TA) n alleles:(TA)5, 6, 7, and 8 were found. These were associated with 10 genotypes: TA5/5, 5/6, 5/7, 5/8, 6/6, 6/7, 6/8, 7/7, 7/8, 8/8. The normal (wild-type)-(TA) 6/6), low- (TA) 7/7, 7/8, 8/8), intermediate- (TA) 5/7, 5/8, 6/7, 6/8), and high-activity (TA) 5/5, 5/6,) genotypes were found in 24.8, 24.8, 41.5, and 8.9% patients and 20.3, 15.6, 61, and 3.1% controls respectively. The general genotype distribution of the patients and control group were not significantly different. There were significant differences in serum bilirubin and lactate dehydrogenase (LDH) of the patients when differentiated by the UGT1A1 (TA) n genotypes (p<0.05). Asymptomatic gallstones were found in 5.9% of patients and were significantly of the low-activity genotypes sub-group 5 (20%) vs 1(1.3%) p = 0.0033. Although, bilirubin and fetal hemoglobin (HbF) of patients with gallstones were significantly different from those without gallstone, only the serum bilirubin was associated with UGT1A1 (TA) n genotypes on multivariate analysis (p < 0.0001).ConclusionThis study highlights the contribution of UGT1A1 polymorphisms, a non-globin genetic factor, to the laboratory and clinical manifestations of young Nigerian SCA patients for the first time. It also shows that children with co-inheritance of low UGT1A1 (TA) n affinity genotypes may be at risk of gallstone, hence the need to follow them up.

Pazopanib-Induced Liver Toxicity in Patients With Metastatic Renal Cell Carcinoma: Effect of UGT1A1 Polymorphism on Pazopanib Dose Reduction, Safety, and Patient Outcomes.

Pazopanib can induce liver toxicity in patients with metastatic renal cell carcinoma (mRCC). We assessed the effect of a TA repeat polymorphism in the UGT1A1 (uridine diphosphate glucuronosyltransferase 1A1) gene encoding uridine diphosphate glucuronosyltransferase 1A1 on liver toxicity, dose reductions, and patient outcomes. Patients with mRCC treated with first-line pazopanib developing liver toxicity underwent genotyping for the UGT1A1 polymorphism. Liver toxicity was assessed using the Common Terminology Criteria for Adverse Events, version 4.0. Progression-free survival and overall survival were assessed using the Kaplan-Meier and log-rank methods. Of 261 patients, 34 (13%) had developed liver toxicity after a median of 29 days (range, 5-155 days). Grade 4, 3, and 2 alanine aminotransferase or bilirubin had increased in 2 (6%), 17 (50%), and 8 (24%) patients, respectively. The UGT1A1 assessment demonstrated that 18 patients (53%) had TA6/TA7, 7 (21%) had TA7/TA7, and 9 (26%) had wild-type TA6/TA6. The UGT1A1 polymorphism was associated with improved median progression-free survival (TA6/TA6, 5.5 months; TA6/TA7, 34.2 months; TA7/TA7, 22.3 months; unknown UGT1A1 status, 9.2 months; UGT1A1 polymorphisms combined vs. unknown status, P= .021). UGT1A1 polymorphism was associated with improved median overall survival (TA6/TA6, 8.1 months, TA6/TA7 or TA7/TA7 not reached, unknown UGT1A1 status, 16.6 months; UGT1A1 polymorphisms combined vs. unknown status, P= .033). Patients with UGT1A1 polymorphism safely resumed pazopanib at ultra-low doses determined by the degree of liver toxicity and UGT1A1 polymorphism. UGT1A1 polymorphisms were associated with improved outcomes, despite pazopanib interruption and dose reductions. UGT1A1 assessment could improve the management of pazopanib-induced liver toxicity in patients with mRCC.

Profiling of UGT1A1*6, UGT1A1*60, UGT1A1*93, and UGT1A1*28 Polymorphisms in Indonesian Neonates With Hyperbilirubinemia Using Multiplex PCR Sequencing.

Background: Single nucleotide polymorphism (SNP) variants of the uridine diphosphate glucuronosyltransferase 1A1 (UGT1A1) gene have been studied as an important factor in neonatal hyperbilirubinemia (jaundice) severity. Specific ethnicities, including Asians, have certain SNPs that appear more frequently than others.Aim: To identify the most common SNPs in Indonesian neonates and their association with the severity of neonatal hyperbilirubinemia.Methods: Eighty-eight inborn and outborn jaundiced infants from three different hospitals (Bengkulu, Jakarta, Biak Papua) across Indonesia were enrolled in this cross-sectional study and their peak total serum bilirubin (TSB) levels assessed. SNP variant analyses of the TATAA box, promoter, and exon 1 regions of UGT1A1 gene from 78 of the 88 infants were carried out using the SNaPshotR Multiplex Polymerase Chain Reaction (PCR) System followed by DNA sequencing.Results: We detected SNP variants UGT1A1*28, UGT1A1*60, UGT1A1*93, and UGT1A1*6 in our population. Mean total serum bilirubin (TSB) was 14.59 ± 5.57 mg/dL. Bivariate analyses using delivery location, gestational age, birth weight, mother's age, and ethnicity were shown to be associated with moderate-to-severe hyperbilirubinemia (p < 0.05). None of the four SNPs appeared to be associated with moderate-to-severe hyperbilirubinemia. In multivariate analysis, however, only the “other ethnic group” (e.g., Chinese, Bengkulu, Papua, Bima) category showed an association with moderate-to-severe hyperbilirubinemia, with an odds ratio of 6.49 (95% CI 1.01–41.67; p < 0.05).Conclusions: We found that the UGT1A1*60 is the most common SNP detected in neonates with hyperbilirubinemia in the Indonesian population. Interestingly, in Indonesia, UGT1A1 polymorphisms do not appear to be associated with differences in the severity of hyperbilirubinemia.

Metabolism of IMM-H004 and Its Pharmacokinetic-Pharmacodynamic Analysis in Cerebral Ischemia/Reperfusion Injured Rats.

IMM-H004, a derivative of coumarin, is a promising candidate for the treatment of cerebral ischemia. The pharmacodynamic mechanisms of IMM-H004 are still under exploration. The present study was conducted to explore the pharmacoactive substances of IMM-H004 from the perspective of drug metabolism. Four metabolites of IMM-H004 including demethylated metabolites M1 and M2, glucuronide conjugate IMM-H004G (M3), and sulfated conjugate M4 were found in rats in vivo. IMM-H004G was the major metabolite in rats and cultured human hepatocytes, and uridine diphosphate-glucuronosyltransferase (UGT) was found to catalyze the metabolism of IMM-H004 in human liver microsomes (HLMs) and rat liver microsomes (RLMs) with high capacity (V max at 3.25 and 5.04 nmol/min/mg protein). Among 13 recombinant human UGT isoforms, UGT1A7, 1A9, 1A8, and 1A1 appeared to be primarily responsible for IMM-H004G formation. The exposure and duration of IMM-H004G (28,948 h × ng/ml of area under the plasma concentration–time curve (AUC), 6.61 h of t 1/2β) was much higher than that of the parent drug (1,638 h × ng/ml of AUC, 0.42 h of t 1/2β) in transient middle cerebral artery occlusion/reperfusion (MCAO/R) rats, consistent with the malondialdehyde (MDA) inhibition effect for at least 10 h. Further pharmacological study revealed that IMM-H004G exhibited a similar neuroprotective activity to that of the parent drug on both oxygen-glucose deprivation injured PC12 cells and transient MCAO/R injured rats. These results demonstrate that both prototype and IMM-H004G are the active pharmaceutical substances, and IMM-H004G, at least in part, contributes to the maintenance of anti-cerebral ischemia efficacy of IMM-H004.

Association between the UGT1A1*28 allele and hyperbilirubinemia in HIV-positive patients receiving atazanavir: a meta-analysis.

Objectives The uridine diphosphate glucuronosyltransferase 1A1 (UGT1A1)*28 allele in HIV-positive patients receiving atazanavir (ATV) might be associated with the risk of hyperbilirubinemia. Owing to mixed and inconclusive results, a meta-analysis was conducted to systematically summarize and clarify this association.Methods Based on a comprehensive search of PubMed, Embase and Web of Science databases, studies investigating the association between UGT1A1 alleles and hyperbilirubinemia was retrieved. We evaluated the strength of this relationship using odds ratios (ORs) with 95% confidence intervals (CIs). Sensitivity analysis was performed by removing each study one at a time and calculating the pooled ORs of the remaining studies to test the robustness of the meta-analysis results. The Q statistic and the I2 index statistic were used to assess heterogeneity. Publication bias was evaluated using Orwin’s fail-safe N test.Results A total of six individual studies were included in this meta-analysis. A significantly increased risk of hyperbilirubinemia was observed in HIV-positive patients receiving ATV with the UGT1A1*1/*28 or UGT1A1*28/*28 genotype, and the risk was higher with the UGT1A1*28/*28 genotype than with the UGT1A1*1/*28 genotype. (UGT1A1*28/*28 versus UGT1A1*1/*28: OR = 3.69, 95%CI = 1.82–7.49; UGT1A1*1/*28 versus UGT1A1*1/*1: OR = 3.50, 95%CI = 1.35–9.08; UGT1A1*28/*28 versus UGT1A1*1/*1: OR = 10.07, 95%CI = 4.39–23.10). All of the pooled ORs were not significantly affected by the remaining studies and different modeling methods, indicating robust results.Conclusions This meta-analysis suggests that the UGT1A1*28 allele represents a biomarker for an increased risk of hyperbilirubinemia in HIV-positive patients receiving ATV.

Pharmacogenetic Analysis of OATP1B1, UGT1A1, and BCRP Variants in Relation to the Pharmacokinetics of Letermovir in Previously Conducted Clinical Studies.

The cytomegalovirus (CMV) viral terminase inhibitor letermovir is indicated for prevention of CMV infection in CMV-seropositive allogeneic hematopoietic stem cell transplant recipients. In this analysis, functional variants in solute carrier organic anion transporter family member 1B1 (SLCO1B1), uridine diphosphate-glucuronosyltransferase 1A1 (UGT1A1), and breast cancer resistance protein (BCRP) were assessed for effects on letermovir pharmacokinetics (PK) using pooled genetic information from 296 participants in 12 phase 1 studies. Letermovir area under the plasma concentration-time curve (AUC) was increased in carriers of the SLCO1B1 variant rs4149056 C allele relative to noncarriers with a geometric mean ratio (GMR) of 1.18 (95% confidence interval [CI], 1.06-1.30) for carriers of 1 copy and 1.42 (1.10-1.84) for carriers of 2 copies of the risk allele C compared with noncarriers. The SLCO1B1 variant rs4149032 T allele was associated with a decrease in letermovir AUC with GMR (95%CI) of 0.93 (0.85-1.02) and 0.82 (0.73-0.92) for carriers of 1 and 2 copies of the risk alleleT, respectively, compared with noncarriers. The UGT1A1*6 variant rs4148323 A allele was present predominantly in Asian participants and was associated with an increase in letermovir AUC compared with noncarriers (GMR, 1.36; 95%CI, 1. 1.07-1.74). SLCO1B1 variant rs2306283, UGT1A1*28 TA promoter repeat, and BCRP variant rs2231142 had no effect on letermovir PK. Together, these data suggest that variants of enzymes and transporters that are involved in the disposition of letermovir in vitro may account for some variability in letermovir PK, but do not affect exposure to a clinically relevant extent.

Research progress in the expression of uridine diphosphate-glucuronosyl transferase 1A1 gene polymorphism

The uridine diphosphate-glucuronosyl transferase 1A1 (UGT1A1) gene mutation can affect the expression of UGT1A1 gene and enzyme activity, and then reduce bilirubin metabolism leading to unconjugated hyperbi-lirubinemia.With the development of molecular biotechnology, more and more studies are trying to identify the pathogenesis of these polymorphisms by analyzing the expression and enzyme activity of UGT1A1 gene polymorphisms.Now, the progresses in the study of the expression of UGT1A1 gene polymorphism were reviewed. Key words: Uridine diphosphate-glucuronosyl transferase 1A1 gene; Polymorphism; Unconjugated hyperbi-lirubinemia; Enzyme activity

Association between UGT1A1 gene polymorphism and safety and efficacy of irinotecan monotherapy as the third-line treatment for advanced gastric cancer.

While uridine diphosphate glucuronosyltransferase (UGT) 1A1 is a key enzyme in the metabolism of irinotecan, relationship between UGT1A1 genotype and safety and efficacy of irinotecan monotherapy in patients with advanced gastric cancer is not clarified. Efficacy and safety in advanced gastric cancer patients, who were tested for UGT1A1*6 and *28 genotype and treated with irinotecan monotherapy as third-line treatment from 2009 to 2014, were evaluated according to the UGT1A1*6 and *28 genotypes. Among 74 patients of the subjects, the genotypes of UGT1A1 were wild-type (WT) in 37 patients (50%), single heterozygosity (SH) in 27 (36.5%) and double heterozygosity or homozygosity (Homo/DH) in 10 (13.5%). The initial dose of irinotecan was reduced in 10 patients (27%) with WT, in 9 (33%) with SH, and in 7 (70%) with Homo/DH. Median overall survival was 6.9 months, 6.3 months, and 2.8 months in the WT, SH and Homo/DH genotypes, associated with median time to treatment failure of 2.4 months, 2.3 months, and 1.3 months, respectively. Among 36 patients with measurable lesion, disease control rates were 47.6%, 41.7% and 33.3% in the WT, SH and Homo/DH genotypes. Grade 3 or higher adverse events of special interest were neutropenia (13%, 22%, and 64% for the WT, SH and Homo/DH genotypes), febrile neutropenia (2%, 7%, and 50%) and diarrhea (6%, 5%, and 21%). The UGT1A1 polymorphism may be related to the clinical outcomes of irinotecan monotherapy as the third-line treatment for advanced gastric cancer.

Oncologic Outcomes in Metastatic Colorectal Cancer with Regorafenib with FOLFIRI as a Third- or Fourth-Line Setting

BACKGROUND: To evaluate the efficacy and toxicities of regorafenib plus irinotecan, dose-escalated on the basis of uridine diphosphate glucuronosyltransferase 1A1 (UGT1A1) genotyping, in previously heavily treated metastatic colorectal cancer (mCRC) and the prognostic values of EGFR expression, KRAS mutations, and tumor sidedness. METHODS: Forty-one patients with mCRC with disease progression after treatment with fluoropyrimidines, oxaliplatin, irinotecan, anti-VEGF, and anti-EGFR MoAbs were subjected to UGT1A1 genotyping and received regorafenib combined with FOLFIRI with dose-escalated irinotecan. RESULTS: The median follow-up period was 10.0 months (1.3-23.5 months). The overall disease control rate was 58.5%, whereas the median progression-free survival (PFS) and overall survival (OS) were 6.0 months and 12.0 months, respectively. KRAS mutations were significantly associated with positive EGFR expression (P = .026). KRAS mutations significantly correlated with a shorter OS than KRAS wild-type (6.0 vs. 14.4 months, P = .014) but had no significant association with PFS. Positive EGFR expression had an inverse correlation with PFS (2.5 vs. 14.0 months, P = .039) and OS (9.6 vs. 19.7 months, P = .044). Moreover, left-sided tumors associated with superior PFS (2.0 vs. 7.0 months, P < .0001) and OS (4.0 vs. 13.0 months, P < .0001), and tumor sidedness was an independent prognostic factor by the multivariate analysis. CONCLUSION: Regorafenib and FOLFIRI concomitant therapy with dose-escalated irinotecan seemed to be potentially practicable with satisfactory oncological results. KRAS mutations and EGFR expression might be predictors of poor oncological outcomes; however, left-sided mCRCs would be more beneficial for concomitant regorafenib and FOLFIRI therapy.