RESUMEN
Ciprofol is a novel short-acting intravenous anaesthetic developed in China that is mainly metabolized by cytochrome P450 2B6 (CYP2B6) and uridine diphosphate glucuronosyltransferase 1A9 (UGT1A9). Currently, insufficient evidence is available to support drugâdrug interactions between ciprofol and CYP2B6 inactivators. Here, we established a high-performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS) method to assess the concentration of ciprofol and investigated the effects of psoralen and clopidogrel on the metabolism of ciprofol in liver microsomes and rats. In rat and human liver microsomes, the median inhibitory concentration (IC50) values of psoralen were 63.31 µmol·L-1 and 34.05 µmol·L-1, respectively, showing mild inhibitory effects on ciprofol metabolism, whereas the IC50 values of clopidogrel were 6.380 µmol·L-1 and 2.565 µmol·L-1, respectively, with moderate inhibitory effects. SD rats were randomly divided into three groups: psoralen (27 mg·kg-1), clopidogrel (7.5 mg·kg-1), and the same volume of 0.5% carboxy methyl cellulose. After 7 days, all rats were injected with 2.4 mg·kg-1 ciprofol. Compared with the control group, the AUC and MRT values of ciprofol in the psoralen and clopidogrel groups were significantly greater, whereas the CL values were significantly lower. In addition, the durations of loss of righting reflex (LORR) in the psoralen and clopidogrel groups were 16.1% and 23.0% longer than that in the control group, respectively. In conclusion, psoralen and clopidogrel inhibit ciprofol metabolism to different degrees and prolong the duration of LORR in rats.
Asunto(s)
Clopidogrel , Citocromo P-450 CYP2B6 , Microsomas Hepáticos , Ratas Sprague-Dawley , Animales , Humanos , Clopidogrel/metabolismo , Clopidogrel/farmacología , Ratas , Microsomas Hepáticos/metabolismo , Masculino , Citocromo P-450 CYP2B6/metabolismo , Inhibidores del Citocromo P-450 CYP2B6/metabolismo , Inhibidores del Citocromo P-450 CYP2B6/farmacología , Ticlopidina/metabolismo , Ticlopidina/farmacología , Ticlopidina/análogos & derivados , Ficusina/farmacología , Espectrometría de Masas en Tándem , Cromatografía Líquida de Alta Presión , Interacciones Farmacológicas , Fenilacetatos , TiofenosRESUMEN
BACKGROUND AND OBJECTIVES: A genetic algorithm (GA) approach was developed to predict drug-drug interactions (DDIs) caused by cytochrome P450 2C8 (CYP2C8) inhibition or cytochrome P450 2B6 (CYP2B6) inhibition or induction. Nighty-eight DDIs, obtained from published in vivo studies in healthy volunteers, have been considered using the area under the plasma drug concentration-time curve (AUC) ratios (i.e., ratios of AUC of the drug substrate administered in combination with a DDI perpetrator to AUC of the drug substrate administered alone) to describe the extent of DDI. METHODS: The following parameters were estimated in this approach: the contribution ratios (CRCYP2B6 and CRCYP2C8, i.e., the fraction of the dose metabolized via CYP2B6 or CYP2C8, respectively) and the inhibitory or inducing potency of the perpetrator drug (IRCYP2B6, IRCYP2C8 and ICCYP2B6, for inhibition of CYP2B6 and CYP2C8, and induction of CYP2B6, respectively). The workflow consisted of three main phases. First, the initial estimates of the parameters were estimated through GA. Then, the model was validated using an external validation. Finally, the parameter values were refined via a Bayesian orthogonal regression using all data. RESULTS: The AUC ratios of 5 substrates, 11 inhibitors and 19 inducers of CYP2B6, and the AUC ratios of 19 substrates and 23 inhibitors of CYP2C8 were successfully predicted by the developed methodology within 50-200% of observed values. CONCLUSIONS: The approach proposed in this work may represent a useful tool for evaluating the suitable doses of a CYP2C8 or CYP2B6 substrates co-administered with perpetrators.
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Algoritmos , Área Bajo la Curva , Citocromo P-450 CYP2B6 , Citocromo P-450 CYP2C8 , Interacciones Farmacológicas , Interacciones Farmacológicas/fisiología , Citocromo P-450 CYP2B6/metabolismo , Citocromo P-450 CYP2B6/genética , Humanos , Citocromo P-450 CYP2C8/metabolismo , Citocromo P-450 CYP2C8/genética , Inhibidores del Citocromo P-450 CYP2C8/farmacología , Inhibidores del Citocromo P-450 CYP2B6/farmacología , Inhibidores del Citocromo P-450 CYP2B6/farmacocinética , Teorema de BayesRESUMEN
Cytochromes P450 (CYPs) play a prominent role in catalyzing phase I xenobiotic biotransformation and account for about 75% of the total metabolism of commercially available drugs, including chemotherapeutics. The gene expression and enzyme activity of CYPs are variable between individuals, which subsequently leads to different patterns of susceptibility to carcinogenesis by genotoxic xenobiotics, as well as differences in the efficacy and toxicity of clinically used drugs. This research aimed to examine the presence of the CYP2B6*9 polymorphism and its possible association with the incidence of B-CLL in Egyptian patients, as well as the clinical outcome after receiving cyclophosphamide chemotherapy. DNA was isolated from whole blood samples of 100 de novo B-CLL cases and also from 100 sex- and age-matched healthy individuals. The presence of the CYP2B6*9 (G516T) polymorphism was examined by PCR-based allele specific amplification (ASA). Patients were further indicated for receiving chemotherapy, and then they were followed up. The CYP2B6*9 variant indicated a statistically significant higher risk of B-CLL under different genetic models, comprising allelic (T-allele vs. G-allele, OR = 4.8, p < 0.001) and dominant (GT + TT vs. GG, OR = 5.4, p < 0.001) models. Following cyclophosphamide chemotherapy, we found that the patients with variant genotypes (GT + TT) were less likely to achieve remission compared to those with the wild-type genotype (GG), with a response percentage of (37.5% vs. 83%, respectively). In conclusion, our findings showed that the CYP2B6*9 (G516T) polymorphism is associated with B-CLL susceptibility among Egyptian patients. This variant greatly affected the clinical outcome and can serve as a good therapeutic marker in predicting response to cyclophosphamide treatment.
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Leucemia Linfocítica Crónica de Células B , Humanos , Citocromo P-450 CYP2B6/genética , Leucemia Linfocítica Crónica de Células B/tratamiento farmacológico , Leucemia Linfocítica Crónica de Células B/epidemiología , Leucemia Linfocítica Crónica de Células B/genética , Incidencia , Egipto/epidemiología , Sistema Enzimático del Citocromo P-450/genética , Genotipo , Ciclofosfamida/efectos adversosRESUMEN
BACKGROUND: Cytochrome P450 (CYP) comprises a group of phase-I metabolizing enzymes that are important in xenobiotics metabolism. Genetic polymorphism of CYPs has been comprehensively studied for their association with a range of diseases. In this study, we assessed single-nucleotide polymorphism (SNP) of CYP1A, CYP1B, CYP2B, and CYP2C and their role in gastrointestinal (GI) cancer susceptibility in the rural population of Maharashtra. MATERIALS AND METHODS: In this hospital-based case-control study, the association of polymorphism of CYP genes was studied by the polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) method. The study subjects included 200 clinically confirmed GI cancer patients and equal number of healthy controls. Odds ratio (OR) with 95% confidence interval (CI) and P value were evaluated to find out the level of association, where P ≤ 0.005 was considered statistically significant. RESULTS: After the analysis of CYP1A1*2A (rs4646903), CYP1B1*3 (rs1059836), CYP2B6*5 (rs3211371), CYP2C8*2 (rs11572103), CYP2C9*2 (rs1799853), and CYP2C9*3 (rs1057910), we noticed that variant (T) allele of CYP2B6*5 possessed significantly elevated risk (OR = 4.43; 95% CI: 2.20-8.90; P < 0.0001) of GI cancer in studied population. The genotypic distribution of G/C heterozygote allele of CYP1B1*3 (OR = 0.19, 95% CI = 0.12-0.32; P < 0.0001) and homozygous variant C/C allele (OR = 0.24, 95% CI = 0.13-0.45; P < 0.0001) showed a negative association with the development of GI cancer. CONCLUSION: The findings from this study supported that polymorphism of CYP2B6*5gene may be involved in the development of GI cancer. However, other SNPs of CYP1A, CYP1B, and CYP2C genes did not signify the risk for GI cancer in the studied population of rural Maharashtra.
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Citocromo P-450 CYP1A1 , Neoplasias Gastrointestinales , Humanos , Citocromo P-450 CYP1A1/genética , Polimorfismo de Nucleótido Simple , Citocromo P-450 CYP2C8/genética , Citocromo P-450 CYP2C9/genética , Estudios de Casos y Controles , Citocromo P-450 CYP2B6/genética , India/epidemiología , Genotipo , Neoplasias Gastrointestinales/genética , Citocromo P-450 CYP1B1/genéticaRESUMEN
Cytochrome P450 mediated substrate metabolism is generally characterized by the formation of reactive intermediates. In vitro and in vivo reaction uncoupling, results in the accumulation and dissociation of reactive intermediates, leading to increased ROS formation. The susceptibility towards uncoupling and altered metabolic activity is partly modulated by pharmacogenomic alleles resulting in amino acid substitutions. A large variability in the prevalence of these alleles has been demonstrated in CYP2B6, with some being predominantly unique to African populations. The aim of this study is to characterize the uncoupling potential of recombinant CYP2B6*1, CYP2B6*6 and CYP2B6*34 metabolism of specific substrates. Therefore, functional effects of these alterations on enzyme activity were determined by quantification of bupropion, efavirenz and ketamine biotransformation using HPLC-MS/MS. Determination of H2O2 levels was performed by the AmplexRed/horseradish peroxidase assay. Our studies of the amino acid substitutions Q172H, K262R and R487S revealed an exclusive use of the peroxide shunt for the metabolism of bupropion and ketamine by CYP2B6*K262R. Ketamine was also identified as a trigger for the peroxide shunt in CYP2B6*1 and all variants. Concurrently, ketamine acted as an uncoupler for all enzymes. We further showed that the expressed CYP2B6*34 allele results in the highest H2O2 formation. We therefore conclude that the reaction uncoupling and peroxide shunt are directly linked and can be substrate specifically induced with K262R carriers being most likely to use the peroxide shunt and R487S carrier being most prone to reaction uncoupling. This elucidates the functional diversity of pharmacogenomics in drug metabolism and safety.
Asunto(s)
Bupropión , Citocromo P-450 CYP2B6 , Ketamina , Alelos , Bupropión/metabolismo , Bupropión/farmacología , Citocromo P-450 CYP2B6/efectos de los fármacos , Citocromo P-450 CYP2B6/genética , Peróxido de Hidrógeno , Ketamina/metabolismo , Ketamina/farmacología , Farmacogenética , Especies Reactivas de Oxígeno , Espectrometría de Masas en Tándem , HumanosRESUMEN
BACKGROUND: Converging lines of evidence indicate that ketamine is a rapid antidepressant for individuals with treatment-resistant depression. Hitherto, no reliable a priori predictors of ketamine response have been reported. Pharmacogenetic biomarkers have yielded mixed results regarding potential candidate genes associated with ketamine's biochemistry as reliable predictors of response. AIMS: No studies have examined the effects of Val66Met and CYP2B6 genotypes on patients receiving repeated infusions of intravenous ketamine. METHODS: In all, 85 participants with major depressive disorder who had previously received four infusions of intravenous ketamine were recruited to the foregoing study. Buccal swabs were collected and genotype variants across the Val66Met and CYP2B6 genes were analyzed. A repeated measures mixed linear model was used to assess change in depressive symptoms, suicidality, and anxiety, correcting for sex and age. Multiple regression was run to determine whether these genetic markers were associated with treatment efficacy for depressive severity, suicidal ideation, anxiolytic response, and degree of dissociation to intravenous ketamine. RESULTS: Participants experienced significant overall reductions in depression, suicide, and anxiety. Overall, 25% met the response criteria and 15% met the remission criteria. However, Val66Met and CYP2B6 did not significantly predict changes in symptoms of depression, suicide, anxiety, or average dissociation. CONCLUSIONS: This study contributes to the growing literature that ketamine efficacy is unlikely to be predicted by single genes, and a pleiotropic approach may likely be necessary for developing reliable predictors of clinical benefits.
Asunto(s)
Trastorno Depresivo Mayor , Trastorno Depresivo Resistente al Tratamiento , Ketamina , Humanos , Ketamina/uso terapéutico , Citocromo P-450 CYP2B6/genética , Trastorno Depresivo Mayor/tratamiento farmacológico , Trastorno Depresivo Mayor/genética , Depresión/tratamiento farmacológico , Factor Neurotrófico Derivado del Encéfalo/genética , Trastorno Depresivo Resistente al Tratamiento/tratamiento farmacológico , Trastorno Depresivo Resistente al Tratamiento/genética , Infusiones IntravenosasRESUMEN
Bupropion is used for treating depression, obesity, and seasonal affective disorder, and for smoking cessation. Bupropion is commonly prescribed, but has complex pharmacokinetics and interindividual variability in metabolism and bioactivation may influence therapeutic response, tolerability, and safety. Bupropion is extensively and stereoselectively metabolized, the metabolites are pharmacologically active, and allelic variation in cytochrome P450 (CYP) 2B6 affects clinical hydroxylation of single-dose bupropion. Genetic effects on stereoselective disposition of steady-state bupropion are not known. In this preplanned secondary analysis of a prospective, randomized, double-blinded, crossover study which compared brand and generic bupropion XL 300 mg drug products, we measured steady-state enantiomeric plasma and urine parent bupropion and primary and secondary metabolite concentrations. This investigation evaluated the influence of genetic polymorphisms in CYP2B6, CYP2C19, and P450 oxidoreductase on the disposition of Valeant Pharmaceuticals Wellbutrin brand bupropion in 67 participants with major depressive disorder. We found that hydroxylation of both bupropion enantiomers was lower in carriers of the CYP2B6*6 allele and in carriers of the CYP2B6 516G>T variant, with correspondingly greater bupropion and lesser hydroxybupropion plasma concentrations. Hydroxylation was 25-50% lower in CYP2B6*6 carriers and one-third to one-half less in 516T carriers. Hydroxylation of the bupropion enantiomers was comparably affected by CYP2B6 variants. CYP2C19 polymorphisms did not influence bupropion plasma concentrations or hydroxybupropion formation but did influence the minor pathway of 4'-hydroxylation of bupropion and primary metabolites. P450 oxidoreductase variants did not influence bupropion disposition. Results show that CYP2B6 genetic variants affect steady-state metabolism and bioactivation of Valeant brand bupropion, which may influence therapeutic outcomes. SIGNIFICANCE STATEMENT: Bupropion, used for depression, obesity, and smoking cessation, undergoes metabolic bioactivation, with incompletely elucidated interindividual variability. We evaluated cytochrome P450 (CYP) 2B6, CYP2C19 and P450 oxidoreductase genetic variants and steady-state bupropion and metabolite enantiomers disposition. Both enantiomers hydroxylation was lower in CYP2B6*6 and CYP2B6 516G>T carriers, with greater bupropion and lesser hydroxybupropion plasma concentrations. CYP2C19 polymorphisms did not affect bupropion or hydroxybupropion but did influence minor 4'-hydroxylation of bupropion and primary metabolites. CYP2B6 variants affect steady-state bupropion bioactivation, which may influence therapeutic outcomes.
Asunto(s)
Bupropión , Bupropión/análogos & derivados , Trastorno Depresivo Mayor , Humanos , Bupropión/farmacocinética , Citocromo P-450 CYP2B6/genética , Citocromo P-450 CYP2C19 , Farmacogenética , Estudios Cruzados , Estudios Prospectivos , Sistema Enzimático del Citocromo P-450/genética , Obesidad , Oxidorreductasas N-Desmetilantes/genéticaRESUMEN
PURPOSE: Midostaurin, approved for treating FLT-3-mutated acute myeloid leukemia and advanced systemic mastocytosis, is metabolized by cytochrome P450 (CYP) 3A4 to two major metabolites, and may inhibit and/or induce CYP3A, CYP2B6, and CYP2C8. Two studies investigated the impact of midostaurin on CYP substrate drugs and oral contraceptives in healthy participants. METHODS: Using sentinel dosing for participants' safety, the effects of midostaurin at steady state following 25-day (Study 1) or 24-day (Study 2) dosing with 50 mg twice daily were evaluated on CYP substrates, midazolam (CYP3A4), bupropion (CYP2B6), and pioglitazone (CYP2C8) in Study 1; and monophasic oral contraceptives (containing ethinylestradiol [EES] and levonorgestrel [LVG]) in Study 2. RESULTS: In Study 1, midostaurin resulted in a 10% increase in midazolam peak plasma concentrations (Cmax), and 3-4% decrease in total exposures (AUC). Bupropion showed a 55% decrease in Cmax and 48-49% decrease in AUCs. Pioglitazone showed a 10% decrease in Cmax and 6% decrease in AUC. In Study 2, midostaurin resulted in a 26% increase in Cmax and 7-10% increase in AUC of EES; and a 19% increase in Cmax and 29-42% increase in AUC of LVG. Midostaurin 50 mg twice daily for 28 days ensured that steady-state concentrations of midostaurin and the active metabolites were achieved by the time of CYP substrate drugs or oral contraceptive dosing. No safety concerns were reported. CONCLUSION: Midostaurin neither inhibits nor induces CYP3A4 and CYP2C8, and weakly induces CYP2B6. Midostaurin at steady state has no clinically relevant PK interaction on hormonal contraceptives. All treatments were well tolerated.
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Bupropión , Citocromo P-450 CYP2B6 , Citocromo P-450 CYP2C8 , Citocromo P-450 CYP3A , Interacciones Farmacológicas , Midazolam , Estaurosporina , Humanos , Área Bajo la Curva , Bupropión/farmacocinética , Bupropión/administración & dosificación , Anticonceptivos Orales/administración & dosificación , Anticonceptivos Orales/farmacología , Anticonceptivos Orales/farmacocinética , Citocromo P-450 CYP2B6/metabolismo , Citocromo P-450 CYP2B6/genética , Citocromo P-450 CYP2C8/metabolismo , Citocromo P-450 CYP3A/metabolismo , Combinación de Medicamentos , Etinilestradiol/farmacocinética , Etinilestradiol/administración & dosificación , Etinilestradiol/farmacología , Voluntarios Sanos , Levonorgestrel/farmacocinética , Levonorgestrel/administración & dosificación , Levonorgestrel/farmacología , Midazolam/farmacocinética , Midazolam/administración & dosificación , Pioglitazona/farmacología , Pioglitazona/administración & dosificación , Pioglitazona/farmacocinética , Estaurosporina/análogos & derivados , Estaurosporina/farmacología , Estaurosporina/farmacocinética , Estaurosporina/administración & dosificación , Masculino , Femenino , Adolescente , Adulto Joven , Adulto , Persona de Mediana EdadRESUMEN
BACKGROUND: Excessive weight gain affects some persons with HIV after switching to integrase strand transfer inhibitor (INSTI)-containing antiretroviral therapy (ART). We studied associations between CYP2B6 genotype and weight gain after ART switch among ACTG A5001 and A5322 participants. METHODS: Eligible participants switched from efavirenz- to INSTI-containing ART, had genotype data, and had weight data at least once from 4 weeks to 2 years post-switch. Multivariable linear mixed effects models adjusted for race/ethnicity, CD4, age, BMI and INSTI type assessed relationships between CYP2B6 genotype and estimated differences in weight change. RESULTS: A total of 159 eligible participants switched ART from 2007 to 2019, of whom 138 had plasma HIV-1 RNAâ <â 200 copies/mL (65 CYP2B6 normal, 56 intermediate, 17 poor metabolizers). Among participants with switch HIV-1 RNAâ <â 200 copies/mL, weight increased in all 3 CYP2B6 groups. The rate of weight gain was greater in CYP2B6 poor than in CYP2B6 normal metabolizers overall, and within 9 subgroups (male, female, White, Black, Hispanic, dolutegravir, elvitegravir, raltegravir, and TDF in the pre-switch regimen); only in Hispanic and elvitegravir subgroups were these associations statistically significant ( P â <â 0.05). Compared to normal metabolizers, CYP2B6 intermediate status was not consistently associated with weight gain. CONCLUSION: CYP2B6 poor metabolizer genotype was associated with greater weight gain after switch from efavirenz- to INSTI-containing ART, but results were inconsistent. Weight gain in this setting is likely complex and multifactorial.
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Fármacos Anti-VIH , Infecciones por VIH , Inhibidores de Integrasa VIH , Humanos , Masculino , Femenino , Citocromo P-450 CYP2B6/genética , Farmacogenética , Inhibidores de Integrasa VIH/uso terapéutico , Benzoxazinas/efectos adversos , Infecciones por VIH/tratamiento farmacológico , Infecciones por VIH/genética , Aumento de Peso/genética , ARN/uso terapéutico , Fármacos Anti-VIH/efectos adversosRESUMEN
Ciprofol is a novel intravenous anesthetic agent. Its major glucuronide metabolite, M4, is found in plasma and urine. However, the specific isoforms of UDP-glucuronosyltransferases (UGTs) that metabolize ciprofol to M4 remain unknown. This study systematically characterized UGTs that contribute to the formation of M4 using human liver microsomes (HLM), human intestinal microsomes (HIM), and human recombinant UGTs. The inhibitory potential of ciprofol and M4 against major human UGTs and cytochrome P450 enzymes (P450s) was also explored. In vitro-in vivo extrapolation (IVIVE) and physiologically-based pharmacokinetic (PBPK) simulations were performed to predict potential in vivo drug-drug interactions (DDIs) caused by ciprofol. Glucuronidation of ciprofol followed Michaelis-Menten kinetics in both HLM and HIM with apparent Km values of 345 and 412 µM, Vmax values of 2214 and 444 nmol min-1·mg protein-1, respectively. The in vitro intrinsic clearances (CLint = Vmax/Km) for ciprofol glucuronidation by HLM and HIM were 6.4 and 1.1 µL min-1·mg protein-1, respectively. Human recombinant UGT studies revealed that UGT1A9 is the predominant isoform mediating M4 formation, followed by UGT1A7, with UGT1A8 playing a minor role. Ciprofol competitively inhibited CYP1A2 (Ki = 12 µM) and CYP2B6 (Ki = 4.7 µM), and noncompetitively inhibited CYP2C19 (Ki = 29 µM). No time-dependent inhibition by ciprofol was noted for CYP1A2, CYP2B6, or CYP2C19. In contrast, M4 showed limited or no inhibitory effects against selected P450s. Neither ciprofol nor M4 inhibited UGTs significantly. Initial IVIVE suggested potential ciprofol-mediated inhibition of CYP1A2, CYP2B6, and CYP2C19 inhibition in vivo. However, PBPK simulations showed no significant effect on phenacetin, bupropion, and S-mephenytoin exposure or peak plasma concentration. Our findings are pertinent for future DDI studies of ciprofol as either a perpetrator or victim drug.
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Citocromo P-450 CYP1A2 , Microsomas Hepáticos , Humanos , Citocromo P-450 CYP2B6/metabolismo , Citocromo P-450 CYP1A2/metabolismo , Citocromo P-450 CYP2C19/metabolismo , Microsomas Hepáticos/metabolismo , Glucuronosiltransferasa/metabolismo , Interacciones Farmacológicas , CinéticaRESUMEN
PURPOSE: The inhibitory effect of Apatinib on cytochrome P450 (CYP450) enzymes has been studied. However, it is unknown whether the inhibition is related to the major metabolites, M1-1, M1-2 and M1-6. METHODS: A 5-in-1 cocktail system composed of CYP2B6/Cyp2b1, CYP2C9/Cyp2c11, CYP2E1/Cyp2e1, CYP2D6/Cyp2d1 and CYP3A/Cyp3a2 was used in this study. Firstly, the effects of APA and its main metabolites on the activities of HLMs, RLMs and recombinant isoforms were examined. The reaction mixture included HLMs, RLMs or recombinant isoforms (CYP3A4.1, CYP2D6.1, CYP2D6.10 or CYP2C9.1), analyte (APA, M1-1, M1-2 or M1-6), probe substrates. The reactions were pre-incubated for 5 min at 37 °C, followed by the addition of NAPDH to initiate the reactions, which continued for 40 min. Secondly, IC50 experiments were conducted to determine if the inhibitions were reversible. The reaction mixture of the "+ NADPH Group" included HLMs or RLMs, 0 to 100 of µM M1-1 or M1-2, probe substrates. The reactions were pre-incubated for 5 min at 37 °C, and then NAPDH was added to initiate reactions, which proceeded for 40 min. The reaction mixture of the "- NADPH Group" included HLMs or RLMs, probe substrates, NAPDH. The reactions were pre-incubated for 30 min at 37 °C, and then 0 to 100 µM of M1-1 or M1-2 was added to initiate the reactions, which proceeded for 40 min. Finally, the reversible inhibition of M1-1 and M1-2 on isozymes was determined. The reaction mixture included HLMs or RLMs, 0 to 10 µM of M1-1 or M1-2, probe substrates with concentrations ranging from 0.25Km to 2Km. RESULTS: Under the influence of M1-6, the activity of CYP2B6, 2C9, 2E1 and 3A4/5 was increased to 193.92%, 210.82%, 235.67% and 380.12% respectively; the activity of CYP2D6 was reduced to 92.61%. The inhibitory effects of M1-1 on CYP3A4/5 in HLMs and on Cyp2d1 in RLMs, as well as the effect of M1-2 on CYP3A in HLMs, were determined to be noncompetitive inhibition, with the Ki values equal to 1.340 µM, 1.151 µM and 1.829 µM, respectively. The inhibitory effect of M1-1 on CYP2B6 and CYP2D6 in HLMs, as well as the effect of M1-2 on CYP2C9 and CYP2D6 in HLMs, were determined to be competitive inhibition, with the Ki values equal to 12.280 µM, 2.046 µM, 0.560 µM and 4.377 µM, respectively. The inhibitory effects of M1-1 on CYP2C9 in HLMs and M1-2 on Cyp2d1 in RLMs were determined to be mixed-type, with the Ki values equal to 0.998 µM and 0.884 µM. The parameters could not be obtained due to the atypical kinetics of CYP2E1 in HLMs under the impact of M1-2. CONCLUSIONS: M1-1 and M1-2 exhibited inhibition for several CYP450 isozymes, especially CYP2B6, 2C9, 2D6 and 3A4/5. This observation may uncover potential drug-drug interactions and provide valuable insights for the clinical application of APA.
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Citocromo P-450 CYP3A , Microsomas Hepáticos , Piridinas , Humanos , Ratas , Animales , Microsomas Hepáticos/metabolismo , Citocromo P-450 CYP3A/metabolismo , Citocromo P-450 CYP2D6/metabolismo , Citocromo P-450 CYP2D6/farmacología , Citocromo P-450 CYP2E1/metabolismo , Isoenzimas/metabolismo , Citocromo P-450 CYP2C9/metabolismo , Citocromo P-450 CYP2B6/metabolismo , NADP/metabolismo , Sistema Enzimático del Citocromo P-450/metabolismoRESUMEN
Ciprofol (HSK3486) is a novel intravenous agent for general anesthesia. In humans, HSK3486 mainly undergoes glucuronidation to form M4 [fraction of clearance (fCL): 62.6%], followed by the formation of monohydroxylated metabolites that further undergo glucuronidation and sulfation to produce M5-1, M5-2, M5-3, and M3 (summed fCL: 35.2%). However, the complete metabolic pathways of HSK3486 in humans remain unclear. In this study, by comparison with chemically synthesized reference standards, three monohydroxylated metabolites [M7-1, 4-hydroxylation with an unbound intrinsic clearance (CLint,u) of 2211 µl/min/mg; M7-2, ω-hydroxylation with a CLint,u of 600 µl/min/mg; and M7-3, (ω-1)-hydroxylation with a CLint,u of 78.4 µl/min/mg] were identified in human liver microsomes, and CYP2B6 primarily catalyzed their formation. In humans, M7-1 was shown to undergo glucuronidation at the 4-position and 1-position by multiple UDP-glucuronosyltransferases (UGTs) to produce M5-1 and M5-3, respectively, or was metabolized to M3 by cytosolic sulfotransferases. M7-2 was glucuronidated at the ω position by UGT1A9, 2B4, and 2B7 to form M5-2. UGT1A9 predominantly catalyzed the glucuronidation of HSK3486 (M4). The CLint,u values for M4 formation in human liver and kidney microsomes were 1028 and 3407 µl/min/mg, respectively. In vitro to in vivo extrapolation analysis suggested that renal glucuronidation contributed approximately 31.4% of the combined clearance. In addition to HSK3486 glucuronidation (M4), 4-hydroxylation (M7-1) was identified as another crucial oxidative metabolic pathway (fCL: 34.5%). Further attention should be paid to the impact of CYP2B6- and UGT1A9-mediated drug interactions and gene polymorphisms on the exposure and efficacy of HSK3486. SIGNIFICANCE STATEMENT: This research elucidates the major oxidative metabolic pathways of HSK3486 (the formation of three monohydroxylated metabolites: M7-1, M7-2, M7-3) as well as definitive structures and formation pathways of these monohydroxylated metabolites and their glucuronides or sulfate in humans. This research also identifies major metabolizing enzymes responsible for the glucuronidation (UGT1A9) and oxidation (CYP2B6) of HSK3486 and characterizes the mechanism of extrahepatic metabolism. The above information is helpful in guiding the safe use of HSK3486 in the clinic.
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Glucuronosiltransferasa , Microsomas Hepáticos , Humanos , Citocromo P-450 CYP2B6/metabolismo , Glucurónidos/metabolismo , Glucuronosiltransferasa/metabolismo , Hígado/metabolismo , Microsomas Hepáticos/metabolismo , Uridina Difosfato/metabolismoRESUMEN
BACKGROUND AND OBJECTIVE: Lorlatinib is a tyrosine kinase inhibitor approved for the treatment of advanced anaplastic lymphoma kinase-positive non-small cell lung cancer. This study assessed the effect of steady-state lorlatinib on the metabolic enzymes cytochrome P450 (CYP) 2B6, CYP2C9, and uridine 5'-diphospho-glucuronosyltransferase (UGT) and the P-glycoprotein (P-gp) transporter. METHODS: Thirty-two patients received a single oral dose of a probe drug on Day - 2 to determine the pharmacokinetics of the probe drug alone. Starting on Day 1, patients received 100 mg oral lorlatinib daily. On Day 15, a single oral dose of the probe drug was administered concurrently with lorlatinib. Pharmacokinetic parameters for these probe substrates were assessed. RESULTS: Plasma exposures of all probe substrates were reduced by lorlatinib compared with the probe alone. The greatest reduction in area under the plasma concentration-time curve from time zero to infinity (AUC∞) and maximum (peak) plasma drug concentration (Cmax) (67% and 63% decrease, respectively) was observed with the P-gp probe substrate fexofenadine. Lorlatinib coadministration also decreased the AUC∞ and Cmax of bupropion (CYP2B6 probe substrate) by 25% and 27%, tolbutamide (CYP2C9 probe substrate) by 43% and 15%, and acetaminophen (UGT probe substrate) by 45% and 28%, respectively. CONCLUSIONS: Lorlatinib is a net moderate inducer of P-gp and a weak inducer of CYP2B6, CYP2C9, and UGT after steady state is achieved with daily dosing. Medications that are P-gp substrates with a narrow therapeutic window should be avoided in patients taking lorlatinib; no dose modifications are needed with substrates of CYP2B6, CYP2C9, or UGT. CLINICALTRIALS: gov: NCT01970865.
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Aminopiridinas , Carcinoma de Pulmón de Células no Pequeñas , Lactamas , Neoplasias Pulmonares , Pirazoles , Humanos , Carcinoma de Pulmón de Células no Pequeñas/tratamiento farmacológico , Citocromo P-450 CYP2C9/genética , Neoplasias Pulmonares/tratamiento farmacológico , Citocromo P-450 CYP2B6 , Miembro 1 de la Subfamilia B de Casetes de Unión a ATP , Uridina , Glucuronosiltransferasa/genética , Interacciones Farmacológicas , Lactamas Macrocíclicas/efectos adversosRESUMEN
BACKGROUND: Maternal obesity (MO) increases fetal androgen concentrations, the prevalence of macrosomia, and predisposes offspring to metabolic dysfunction in later life, especially males. These risks may be, in part, the result of increased liver-specific androgen signalling pathway activity in utero. Androgen signalling activity can be suppressed by androgen metabolism via cytochrome P450 (CYP) isoenzymes (CYP2B6, CYP3A) or through inhibition of the full-length androgen receptor (AR-FL) via the antagonistic isoform, AR-45. We hypothesised MO impairs CYP enzyme activity and AR-45 expression in male fetal livers, thereby enhancing activity of androgen signalling pathways. METHODS: Nine months prior to pregnancy, nulliparous female baboons were assigned to either ad libitum control or high fat diet. At 165 day (d) gestation (term, 180 d) fetal liver was collected (n = 6/sex/group). CYP activity was quantified using functional assays; subcellular AR expression was measured using Western blot. RESULTS: CYP2B6 and CYP3A activity, and nuclear expression of AR-45, was reduced in MO males only. Nuclear AR-45 expression was inversely related with fetal body weight of MO males only. CONCLUSIONS: Reduced CYP2B6 and CYP3A activity in conjunction with decreased nuclear AR-45 expression may enhance liver androgen signalling in males from MO pregnancies, thereby increasing the risk of macrosomia, as well as metabolic dysfunction in later life.
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Andrógenos , Obesidad Materna , Humanos , Femenino , Embarazo , Masculino , Andrógenos/metabolismo , Obesidad Materna/metabolismo , Citocromo P-450 CYP3A/metabolismo , Citocromo P-450 CYP2B6/metabolismo , Macrosomía Fetal/metabolismo , Receptores Androgénicos/metabolismo , Hígado/metabolismo , IsoenzimasRESUMEN
Genetic variation in CYP2B6 and CYP2A6 is known to impact interindividual response to antiretrovirals, nicotine, and bupropion, among other drugs. However, the full catalogue of clinically relevant pharmacogenetic variants in these genes is yet to be established, especially across African populations. This study therefore aimed to characterize the star allele (haplotype) distribution in CYP2B6 and CYP2A6 across diverse and understudied sub-Saharan African (SSA) populations. We called star alleles from 961 high-depth full genomes using StellarPGx, Aldy, and PyPGx. In addition, we performed CYP2B6 and CYP2A6 star allele frequency comparisons between SSA and other global biogeographical groups represented in the new 1000 Genomes Project high-coverage dataset (n = 2,000). This study presents frequency information for star alleles in CYP2B6 (e.g., *6 and *18; frequency of 21-47% and 2-19%, respectively) and CYP2A6 (e.g., *4, *9, and *17; frequency of 0-6%, 3-10%, and 6-20%, respectively), and predicted phenotypes (for CYP2B6), across various African populations. In addition, 50 potentially novel African-ancestry star alleles were computationally predicted by StellarPGx in CYP2B6 and CYP2A6 combined. For each of these genes, over 4% of the study participants had predicted novel star alleles. Three novel star alleles in CYP2A6 (*54, *55, and *56) and CYP2B6 apiece, and several suballeles were further validated via targeted Single-Molecule Real-Time resequencing. Our findings are important for informing the design of comprehensive pharmacogenetic testing platforms, and are highly relevant for personalized medicine strategies, especially relating to antiretroviral medication and smoking cessation treatment in Africa and the African diaspora. More broadly, this study highlights the importance of sampling diverse African ethnolinguistic groups for accurate characterization of the pharmacogene variation landscape across the continent.
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Nicotina , Farmacogenética , Humanos , Citocromo P-450 CYP2B6/genética , Citocromo P-450 CYP2A6/genética , Frecuencia de los Genes , África del Sur del Sahara , Genotipo , AlelosRESUMEN
Tramadol is an important minor opioid prescribed for pain management. In this study, we analyzed the well-known impact of CYP2D6 genetic variation and 60 additional variants in eight candidate genes (i.e., ABCG2, SLCO1B1, CYP2D6, CYP2B6, CYP2C19, CYP2C9, CYP3A5, and CYP3A4) on tramadol efficacy and safety. Some 108 patients with pain after surgery admitted to a post-anesthesia care unit (PACU) and prescribed tramadol were recruited. They were genotyped, and tramadol M1/M2 metabolite concentrations were determined by a newly validated HPLC-MS/MS method. CYP2D6 intermediate (IM) and poor (PM) metabolizers showed lower M1 concentrations adjusted for dose/weight at 30 and 120 min compared to ultrarapid (UM) and normal (NM) metabolizers (univariate p < 0.001 and 0.020, multivariate p < 0.001 and 0.001, unstandardized ß coefficients = 0.386 and 0.346, R2 = 0.146 and 0.120, respectively). CYP2B6 PMs (n = 10) were significantly related to a higher reduction in pain 30 min after tramadol intake (univariate p = 0.038, multivariate p = 0.016, unstandardized ß coefficient = 0.224, R2 = 0.178), to lower PACU admission time (p = 0.007), and to lower incidence of adverse drug reactions (p = 0.038) compared to the other phenotypes. CYP3A4 IMs and PMs showed a higher prevalence of drowsiness and dizziness (p = 0.028 and 0.005, respectively). Our results suggest that the interaction of CYP2B6 and CYP2D6 phenotypes may be clinically relevant, pending validation of these results in large, independent cohorts. Additional research is required to clarify the impact of CYP3A4 genetic variation on tramadol response.
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Citocromo P-450 CYP2D6 , Tramadol , Humanos , Citocromo P-450 CYP2D6/genética , Citocromo P-450 CYP3A/metabolismo , Citocromo P-450 CYP2B6/genética , Espectrometría de Masas en Tándem , Analgésicos Opioides , Fenotipo , Genotipo , Dolor Postoperatorio , Transportador 1 de Anión Orgánico Específico del Hígado/genéticaRESUMEN
Methadone is cleared predominately by hepatic cytochrome P450 (CYP) 2B6-catalyzed metabolism to inactive metabolites. CYP2B6 also catalyzes the metabolism of several other drugs. Methadone and CYP2B6 are susceptible to pharmacokinetic drug-drug interactions. Use of natural products such as herbals and other botanicals is substantial and growing, and concomitant use of prescription medicines and non-prescription herbals is common and may result in interactions, often precipitated by CYP inhibition. Little is known about herbal product effects on CYP2B6 activity, and CYP2B6-catalyzed methadone metabolism. We screened a family of natural product compounds used in traditional medicines, herbal teas, and synthetic analogs of compounds found in plants, including kavalactones, flavokavains, chalcones and gambogic acid, for inhibition of expressed CYP2B6 activity and specifically inhibition of CYP2B6-mediated methadone metabolism. An initial screen evaluated inhibition of CYP2B6-catalyzed 7-ethoxy-4-(trifluoromethyl) coumarin O-deethylation. Hits were further evaluated for inhibition of racemic methadone metabolism, including mechanism of inhibition and kinetic constants. In order of decreasing potency, the most effective inhibitors of methadone metabolism were dihydromethysticin (competitive, K i 0.074 µM), gambogic acid (noncompetitive, K i 6 µM), and 2,2'-dihydroxychalcone (noncompetitive, K i 16 µM). Molecular modeling of CYP2B6-methadone and inhibitor binding showed substrate and inhibitor binding position and orientation and their interactions with CYP2B6 residues. These results show that CYP2B6 and CYP2B6-catalyzed methadone metabolism are inhibited by certain natural products, at concentrations which may be clinically relevant. SIGNIFICANCE STATEMENT: This investigation identified several natural product constituents which inhibit in vitro human recombinant CYP2B6 and CYP2B6-catalyzed N-demethylation of the opioid methadone. The most potent inhibitors (K i) were dihydromethysticin (0.074 µM), gambogic acid (6 µM) and 2,2'-dihydroxychalcone (16 µM). Molecular modeling of ligand interactions with CYP2B6 found that dihydromethysticin and 2,2'-dihydroxychalcone bound at the active site, while gambogic acid interacted with an allosteric site on the CYP2B6 surface. Natural product constituents may inhibit CYP2B6 and methadone metabolism at clinically relevant concentrations.
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Productos Biológicos , Chalconas , Metadona , Humanos , Metadona/farmacocinética , Citocromo P-450 CYP2B6/metabolismo , Oxidorreductasas N-Desmetilantes/metabolismo , Productos Biológicos/farmacología , Productos Biológicos/metabolismo , Microsomas Hepáticos/metabolismoRESUMEN
BACKGROUND: A considerable inter-individual variability has been reported in the relationship between methadone doses applied and serum concentrations achieved in methadone maintenance treatment. However, the underlying causes for this variability are not fully understood. OBJECTIVES: We investigated the influence of genetic, pathophysiological and pharmacological factors on serum methadone concentration-to-dose ratio (CDR) and discussed the clinical implications of the findings. METHODS: We used data from two retrospective laboratory databases and a prospective cohort study to investigate the impact on methadone CDR of hepatic cytochrome P450 enzyme system (CYP) genetic polymorphisms, age, sex, concomitant medication, liver fibrosis and body mass index through linear mixed model analyses. FINDINGS: A positive association was found between CDR and the homozygous CYP2B6*6 genotype, concurrent treatment with CYP3A4 inhibitors and body mass index. CDR was lower among women and during concomitant use of CYP inducers. CDR was not associated with age or the degree of liver fibrosis in our investigations. CONCLUSIONS: This research work supports the need for individually tailored dosage considering the various factors that influence methadone CDR. The gained knowledge can contribute to reducing the risks associated with the treatment and optimizing the desired outcomes.
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Metadona , Trastornos Relacionados con Opioides , Humanos , Femenino , Metadona/uso terapéutico , Analgésicos Opioides , Estudios Retrospectivos , Estudios Prospectivos , Sistema Enzimático del Citocromo P-450/genética , Cirrosis Hepática/tratamiento farmacológico , Citocromo P-450 CYP2B6/genéticaRESUMEN
BACKGROUND: The expression and activity of cytochrome P450 2B6 (CYP2B6) may be related to the metabolic associated fat liver disease (MAFLD). Since constitutive androstane receptor (CAR) is a classic transcriptional regulator of CYP2B6, and the single nucleotide polymorphisms (SNPs) of CYP2B6 and CAR are both associated with adverse reactions of efavirenz, we hypothesized that genetic polymorphisms of CAR might also result in additional interindividual variability in CYP2B6. This study was devoted to explore the association between CYP2B6 and CAR SNPs and susceptibility to MAFLD. MATERIALS AND METHODS: A total of 590 objects of study (118 with MAFLD and 472 healthy control) between December 2014 and April 2018 were retrospectively enrolled. Twenty-two selected SNPs in CYP2B6 and CAR were genotyped with a custom-designed 48-plex SNP Scan TM® Kit. The frequencies of the alleles, genotypes and genetic models of the variants were compared between the two groups. The odds ratios (ORs) and the corresponding 95% confidence intervals (CIs) were calculated. RESULTS: The T allele of rs3745274 in CYP2B6 was associated with a decreased risk for MAFLD (OR 0.610; 95% CI: 0.451-0.825, p = 0.001) which was still statistically significant after adjusting with Bonferroni method(p = 0.014) The allele, genotype and genetic model frequencies were similar in the two groups for the other twenty-one SNPs (all P > 0.05). There were no multiplicative or additive interactions between the SNPs. CONCLUSION: Our study revealed that rs3745274 variants in CYP2B6 is associated with susceptibility to MAFLD in the Han Chinese population.
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Fármacos Anti-VIH , Enfermedad del Hígado Graso no Alcohólico , Humanos , Citocromo P-450 CYP2B6/genética , Estudios Retrospectivos , Polimorfismo de Nucleótido Simple , Genotipo , China/epidemiologíaRESUMEN
Lekethromycin (LKMS) is a synthetic macrolide compound derivative intended for use as a veterinary medicine. Since there have been no in vitro studies evaluating its potential for drug-drug interactions related to cytochrome P450 (CYP450) enzymes, the effect of the inhibitory mechanisms of LKMS on CYP450 enzymes is still unclear. Thus, this study aimed to evaluate the inhibitory effects of LKMS on dog CYP450 enzymes. A cocktail approach using ultra-performance liquid chromatography-tandem mass spectrometry was conducted to investigate the inhibitory effect of LKMS on canine CYP450 enzymes. Typical probe substrates of phenacetin, coumarin, bupropion, tolbutamide, dextromethorphan, chlorzoxazone, and testosterone were used for CYP1A2, CYP2A6, CYP2B6, CYP2C9, CYP2D6, CYP2E1, and CYP3A4, respectively. This study showed that LKMS might not be a time-dependent inhibitor. LKMS inhibited CYP2A6, CYP2B6, and CYP2D6 via mixed inhibition. LKMS exhibited mixed-type inhibition against the activity of CYP2A6 with an inhibition constant (Ki) value of 135.6 µΜ. LKMS inhibited CYP2B6 in a mixed way, with Ki values of 59.44 µM. A phenotyping study based on an inhibition assay indicated that CYP2D6 contributes to the biotransformation of LKMS. A mixed inhibition of CYP2D6 with Ki values of 64.87 µM was also observed. Given that this study was performed in vitro, further in vivo studies should be conducted to identify the interaction between LKMS and canine CYP450 enzymes to provide data support for the clinical application of LKMS and the avoidance of adverse interactions between other drugs.