RESUMEN

This report presents challenging psychopharmacotherapy management of a psychotic disorder in a patient with a delicate pharmacogenetic profile and drug-drug interactions. A 31-year old woman diagnosed with schizophrenia in 2017 was referred by her psychiatrist to a clinical pharmacologist for interpretation of a pharmacogenetic test and advice regarding optimal psychopharmacotherapy. In spite of adherence to aripiprazole, olanzapine, risperidone, and levomepromazine, and rational anxiolytic therapy, she still experienced anxiety, anhedonia, loss of appetite, sleeping problems, and auditory hallucinations with commands to harm herself. Due to a lack of alternative therapeutic steps, low aripiprazole serum concentrations, and a lack of explanation for pharmacotherapy unresponsiveness, pharmacogenetic testing was performed. The patient was defined as CYP2D6 *1/*1, CYP1A2 *1F/*1F, CYP3A4 *1/*1B, CYP3A5 *1/*3, and having increased activity of the enzymes UGT1A4 and UGT2B7, intermediate activity of ABCB1 transporter, and low activity of COMT. Carbamazepine was discontinued, aripiprazole was increased to a maximum of 30 mg/day orally with long-acting injection (400 mg monthly), and olanzapine was increased to a daily dose of 35 mg orally. These changes led to an optimal therapeutic drug concentration and improved clinical status. At the last follow-up, the patient was without severe auditory hallucinations, became more engaged in daily life, had more interaction with others, had found a job, and even had started an emotional relationship. In psychiatry, pharmacogenetic testing is an important tool for guiding pharmacological therapy, particularly in patients with an unsatisfactory clinical response and a lack of alternative therapeutic steps for pharmacotherapy unresponsiveness.

Asunto(s)

Antipsicóticos , Interacciones Farmacológicas , Humanos , Adulto , Femenino , Antipsicóticos/administración & dosificación , Antipsicóticos/uso terapéutico , Trastornos Psicóticos/tratamiento farmacológico , Trastornos Psicóticos/genética , Aripiprazol/administración & dosificación , Aripiprazol/uso terapéutico , Esquizofrenia/tratamiento farmacológico , Esquizofrenia/genética , Citocromo P-450 CYP1A2/genética , Pruebas de Farmacogenómica , Farmacogenética , Citocromo P-450 CYP3A/genética , Citocromo P-450 CYP2D6/genética

RESUMEN

Aripiprazole once-monthly (AOM) exhibits an important interindividual pharmacokinetic variability with significant implications for its clinical use. CYP2D6 and CYP3A4 highly contributes to this variability, as they metabolize aripiprazole (ARI) into its active metabolite, dehydroaripiprazole (DHA) and the latter into inactive metabolites. This study aims to evaluate the effect of CYP2D6 and CYP3A4 polymorphisms in combination and the presence of concomitant inducers and inhibitors of this cytochromes on ARI and DHA plasma concentrations in a real clinical setting. An observational study of a cohort of 74 Caucasian patients under AOM treatment was conducted. Regarding CYP2D6, higher concentrations were found for active moiety (ARI plus DHA) (AM) (67 %), ARI (67 %) and ARI/DHA ratio (77 %) for poor metabolizers (PMs) compared to normal metabolizers (NMs). No differences were found for DHA. PMs for both CYP2D6 and CYP3A4 showed a 58 % higher AM and 66 % higher plasma concentration for ARI compared with PMs for CYP2D6 and NMs for CYP3A4. In addition, PMs for both CYP2D6 and CYP3A4 have 45 % higher DHA concentrations than NMs for both cytochromes and 41 % more DHA than PMs for CYP2D6 and NMs for CYP3A4, suggesting a significant role of CYP3A4 in the elimination of DHA. Evaluating the effect of CYPD26 and CYP3A4 metabolizing state in combination on plasma concentrations of ARI, DHA and parent-to-metabolite ratio, considering concomitant treatments with inducers and inhibitor, could optimize therapy for patients under AOM treatment.

Asunto(s)

Antipsicóticos , Aripiprazol , Citocromo P-450 CYP2D6 , Citocromo P-450 CYP3A , Humanos , Citocromo P-450 CYP2D6/genética , Citocromo P-450 CYP2D6/metabolismo , Aripiprazol/farmacocinética , Citocromo P-450 CYP3A/genética , Citocromo P-450 CYP3A/metabolismo , Masculino , Femenino , Adulto , Antipsicóticos/farmacocinética , Antipsicóticos/sangre , Antipsicóticos/uso terapéutico , Persona de Mediana Edad , Polimorfismo Genético/genética , Quinolonas/farmacocinética , Quinolonas/sangre , Adulto Joven , Piperazinas/farmacocinética , Piperazinas/sangre , Anciano , Preparaciones de Acción Retardada/farmacocinética

RESUMEN

African American (AA) kidney transplant recipients (KTRs) have poor outcomes, which may in-part be due to tacrolimus (TAC) sub-optimal immunosuppression. We previously determined the common genetic regulators of TAC pharmacokinetics in AAs which were CYP3A5 *3, *6, and *7. To identify low-frequency variants that impact TAC pharmacokinetics, we used extreme phenotype sampling and compared individuals with extreme high (n = 58) and low (n = 60) TAC troughs (N = 515 AA KTRs). Targeted next generation sequencing was conducted in these two groups. Median TAC troughs in the high group were 7.7 ng/ml compared with 6.3 ng/ml in the low group, despite lower daily doses of 5 versus 12 mg, respectively. Of 34,542 identified variants across 99 genes, 1406 variants were suggestively associated with TAC troughs in univariate models (p-value < 0.05), however none were significant after multiple testing correction. We suggest future studies investigate additional sources of TAC pharmacokinetic variability such as drug-drug-gene interactions and pharmacomicrobiome.

Asunto(s)

Negro o Afroamericano , Inmunosupresores , Trasplante de Riñón , Tacrolimus , Adulto , Femenino , Humanos , Masculino , Persona de Mediana Edad , Negro o Afroamericano/genética , Citocromo P-450 CYP3A/genética , Variación Genética , Secuenciación de Nucleótidos de Alto Rendimiento , Inmunosupresores/farmacocinética , Variantes Farmacogenómicas , Fenotipo , Tacrolimus/farmacocinética , Tacrolimus/uso terapéutico , Receptores de Trasplantes

RESUMEN

The influence of genetic variants related to opioid use disorder (OUD) was evaluated using multiple logistic regression analysis in self-reported assigned African American/Afro-Caribbean and European biogeographical ancestry groups (BGAGs) and by sex. From a sample size of 1301 adult patients (>18 years of age) seen in emergency departments of three medical centers in Ohio, six variants were found to be associated with OUD. Two of the variants, rs2740574 (CYP3A4) and rs324029 (DRD3), were included in the analysis having met criteria of at least five subjects for each BGAG, variant carrier status, and OUD status combinations. Variant carriers in the African/Afro-Caribbean BGAG had slightly lower predicted probabilities of OUD. Variant carriers in the European BGAG had slightly higher predicted probabilities of OUD. Relative to sex, all the six variants met evaluation criteria (five subjects for all sex, variant, and OUD status combinations). No statistically significant interactions were found between a given variant, BGAGs and sex. Findings suggest variant testing relative to OUD risk can be applied across BGAGs and sex, however, studies in larger populations are needed.

Asunto(s)

Alelos , Negro o Afroamericano , Trastornos Relacionados con Opioides , Población Blanca , Humanos , Masculino , Femenino , Trastornos Relacionados con Opioides/genética , Adulto , Negro o Afroamericano/genética , Población Blanca/genética , Autoinforme , Persona de Mediana Edad , Región del Caribe , Predisposición Genética a la Enfermedad/genética , Citocromo P-450 CYP3A/genética , Polimorfismo de Nucleótido Simple/genética , Factores de Riesgo , Población Negra/genética

RESUMEN

Calcineurin inhibitors (CNIs) are the mainstay of immunosuppression in kidney transplantation. Interpatient variability in the disposition of calcineurin inhibitors is a well-researched phenomenon and has a well-established genetic contribution. There is great diversity in the makeup of African genomes, but very little is known about the pharmacogenetics of CNIs and transplant outcomes. This review focuses on genetic variants of calcineurin inhibitors' metabolizing enzymes (CYP3A4, CYP3A5), related molecules (POR, PPARA) and membrane transporters involved in the metabolism of calcineurin inhibitors. Given the genetic diversity across the African continent, it is imperative to generate pharmacogenetic data, especially in the era of personalized medicine and emphasizes the need for studies specific to African populations. The study of allelic variants in populations where they have greater frequencies will help answer questions regarding their impact. We aim to fill the knowledge gaps by reviewing existing research and highlighting areas where African research can contribute.

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Research on the pharmacogenetics of calcineurin inhibitors in kidney transplant recipients is truly wanting in data from the African continent. Given Africa's vast genetic diversity, it is necessary to intensify efforts to generate data from Africa in this field.

Asunto(s)

Inhibidores de la Calcineurina , Inmunosupresores , Trasplante de Riñón , Farmacogenética , Humanos , Inhibidores de la Calcineurina/uso terapéutico , Trasplante de Riñón/tendencias , Farmacogenética/métodos , Inmunosupresores/uso terapéutico , Receptores de Trasplantes , Población Negra/genética , Citocromo P-450 CYP3A/genética , África

RESUMEN

BACKGROUND: Tacrolimus is the core basic immunosuppressant after transplantation. Cytochrome P450 3A5 (CYP3A5) is the main enzyme involved in tacrolimus metabolism, and rs776746A>G is the most frequently studied polymorphism in the CYP3A5 gene. The aim of this study was to investigate the effect of CYP3A5 gene polymorphisms on tacrolimus blood concentrations and acute graft versus host disease (GVHD) in patients with allogeneic hematopoietic stem cell transplantation (allo-HSCT). METHODS: This study included adult patients who received allo-HSCT at the First Affiliated Hospital of Wannan Medical College from January 2021 to June 2022, and received postoperative treatment with tacrolimus. Tacrolimus blood levels were obtained by fully automatic chemiluminescence immunoassay analyzer. Polymerase chain reaction/restriction fragment length polymorphism was used to genotype for CYP3A5*3 allelic variants. RESULTS: In a total of 50 transplant patients, 30 patients were detected with CYP3A5*3/*3 genotype, 15 patients with CYP3A5*1/*3 genotype, and 5 patients with CYP3A5*1/*1 genotype. The initial tacrolimus blood concentrations in allo-HSCT patients with CYP3A5*1/*1, *1/*3, and *3/*3 genes were 7.75, 8.61, and 10.19 ng/mL, respectively; The initial blood concentration/dose (C/D) ratios were 4.08, 4.42 and 5.66 ng/(mL·mg), respectively. The C/D ratios of allo-HSCT patients carrying CYP3A5*1/*1, *1/*3, and *3/*3 genes were 4.35 and 4.71 and 5.58, 4.19, 4.56 and 5.71 ng/(mL·mg) in the second and 3rd weeks after operation. These results showed that the blood concentration and C/D ratio of tacrolimus in patients with CYP3A5*3/*3 genotype were significantly higher than those in patients with CYP3A5*1/*3 or CYP3A5*1/*1 genotype. Moreover, the incidence of acute GVHD after allo-HSCT in patients with CYP3A5*1/*1 genotype was significantly higher than that in patients with CYP3A5*1/*3 or CYP3A5*3/*3 genotype. CONCLUSIONS: Most patients carry the mutant allele CYP3A5*3. CYP3A5 gene polymorphisms affect tacrolimus blood concentrations and acute GVHD after allo-HSCT.

Asunto(s)

Citocromo P-450 CYP3A , Enfermedad Injerto contra Huésped , Trasplante de Células Madre Hematopoyéticas , Inmunosupresores , Tacrolimus , Trasplante Homólogo , Humanos , Citocromo P-450 CYP3A/genética , Tacrolimus/sangre , Trasplante de Células Madre Hematopoyéticas/efectos adversos , Masculino , Adulto , Femenino , Inmunosupresores/sangre , Inmunosupresores/uso terapéutico , Inmunosupresores/efectos adversos , Inmunosupresores/farmacocinética , Enfermedad Injerto contra Huésped/sangre , Enfermedad Injerto contra Huésped/genética , Persona de Mediana Edad , Adulto Joven , Genotipo , Polimorfismo Genético , Adolescente

RESUMEN

Vanillin (VAN) is a common flavoring agent that can cause liver damage when ingested in large amounts. Nevertheless, the precise processes responsible for its toxicity remain obscure. The present research aimed to examine the metabolic activation of VAN and establish a potential correlation between its reactive metabolites and its cytotoxicity. In rat liver microsomes incubated with VAN, reduced glutathione/N-acetylcysteine (GSH/NAC), and nicotinamide adenine dinucleotide phosphate (NADPH), two conjugates formed from GSH and one conjugate derived from NAC were identified. We also discovered one GSH conjugate in both the bile obtained from rats and the rat primary hepatocytes that were subjected to VAN exposure. Additionally, the NAC conjugate exerted in the urine of VAN-treated rats was observed. These results indicate that a quinone intermediate was produced from VAN both in vitro and in vivo. Next, we identified CYP3A as the main enzyme that initiated the bioactive pathway of VAN. After the activity of CYP3A was selectively inhibited by ketoconazole (KTZ), the generation of the GSH conjugate declined in hepatocytes exposed to VAN. Furthermore, the vulnerability to VAN-induced toxicity was alleviated by KTZ in hepatocytes. Thus, we propose that the cytotoxicity of VAN may derive from metabolic activation triggered by CYP3A.

Asunto(s)

Activación Metabólica , Benzaldehídos , Citocromo P-450 CYP3A , Hepatocitos , Microsomas Hepáticos , Ratas Sprague-Dawley , Animales , Benzaldehídos/metabolismo , Benzaldehídos/farmacología , Hepatocitos/metabolismo , Hepatocitos/efectos de los fármacos , Ratas , Masculino , Citocromo P-450 CYP3A/metabolismo , Citocromo P-450 CYP3A/genética , Microsomas Hepáticos/metabolismo , Microsomas Hepáticos/efectos de los fármacos , Glutatión/metabolismo , Aromatizantes/metabolismo , Aromatizantes/química , Aromatizantes/toxicidad

RESUMEN

OBJECTIVE: This study aimed to explore the potential role of CYP3A5 (c. 6986A>G) gene polymorphism in predicting kidney function impairment in patients with hypertension who did not have elevated serum cystatin C. METHODS: We recruited a group of patients with hypertension who did not have elevated cystatin C and analyzed the CYP3A5 (c. 6986A>G) gene polymorphism. Chi-square tests were used to compare the clinical characteristics and genotypic distribution between the two groups. Logistic regression analysis was used to explore the association between CYP3A5 (c.6986A>G) gene polymorphism and renal function impairment in hypertension with non-elevated cystatin. RESULTS: In patients with hypertension who participated in the study, there was a significant association between CYP3A5 (c. 6986A>G) gene polymorphism and kidney function impairment (p < 0.05). Patients with the CYP3A5 (c. 6986A>G) mutation display a greater risk of kidney function impairment. CONCLUSION: CYP3A5 (c. 6986A>G) gene AA homozygote polymorphism significantly increases risk of kidney function impairment in patients with hypertension with normal cystatin C. However, further studies are needed to validate this association and to further understand the mechanism of CYP3A5 (c. 6986A>G) gene polymorphism in kidney function impairment in patients with hypertension.

Asunto(s)

Biomarcadores , Cistatina C , Citocromo P-450 CYP3A , Predisposición Genética a la Enfermedad , Hipertensión , Riñón , Polimorfismo de Nucleótido Simple , Humanos , Citocromo P-450 CYP3A/genética , Masculino , Femenino , Persona de Mediana Edad , Hipertensión/genética , Hipertensión/fisiopatología , Hipertensión/diagnóstico , Cistatina C/sangre , Cistatina C/genética , Biomarcadores/sangre , Factores de Riesgo , Riñón/fisiopatología , Fenotipo , Estudios de Asociación Genética , Homocigoto , Adulto , Anciano , Enfermedades Renales/genética , Enfermedades Renales/diagnóstico , Enfermedades Renales/sangre , Enfermedades Renales/fisiopatología , Enfermedades Renales/enzimología , Frecuencia de los Genes , Estudios de Casos y Controles , Medición de Riesgo

RESUMEN

BACKGROUND: Acute immune rejection remains a challenge in the post-transplant period, with approximately 7.8% of renal transplant recipients experiencing rejection episodes within the first year. Genetic polymorphisms in the CYP3A5 gene, which influences tacrolimus metabolism, have garnered interest regarding their association with clinical outcomes in renal transplantation. METHODS: This retrospective correlation study analysed clinical data from kidney transplant patients who received tacrolimus treatment at our hospital from June 2015 to June 2023. The presence of CYP3A5 gene polymorphisms, tacrolimus trough levels, and demographic and clinical data were collected and analysed. RESULTS: A total of 105 kidney transplant patients were included. Patients were divided into acute immune rejection (n = 56) and non-acute immune rejection (n = 49) groups. The distribution of CYP3A5 gene polymorphisms differed significantly between the acute rejection and non-acute rejection groups (p = 0.037). The acute rejection group exhibited a higher frequency of CYP3A5 *1/*1 or *1/*3 genotypes than the non-acute rejection group. No statistically significant differences were found in the tacrolimus trough levels between the two groups. Correlation analysis revealed a statistically significant correlation between CYP3A5 gene polymorphism and post-transplant acute immune rejection (r = 0.223, p < 0.05). CONCLUSIONS: This study demonstrated a significant association between CYP3A5 gene polymorphism and the risk of post-transplant acute immune rejection in renal transplant recipients receiving tacrolimus therapy. These findings highlighted the importance of genetic variability in tacrolimus metabolism when managing immunosuppressive therapy in transplant recipients.

Asunto(s)

Citocromo P-450 CYP3A , Rechazo de Injerto , Inmunosupresores , Trasplante de Riñón , Polimorfismo Genético , Tacrolimus , Humanos , Tacrolimus/uso terapéutico , Citocromo P-450 CYP3A/genética , Rechazo de Injerto/genética , Masculino , Femenino , Estudios Retrospectivos , Inmunosupresores/uso terapéutico , Enfermedad Aguda , Persona de Mediana Edad , Adulto , Correlación de Datos

RESUMEN

This study aimed to elucidate the impact of variations in liver enzyme activity, particularly CYP3A4, on the metabolism of furmonertinib. An in vitro enzyme incubation system was established for furmonertinib using liver microsomes and recombinant CYP3A4 baculosomes, with analytes detected by LC-MS/MS. The pharmacokinetic characteristics of furmonertinib were studied in vivo using Sprague-Dawley rats. It was found that telmisartan significantly inhibited the metabolism of furmonertinib, as demonstrated by a significant increase in the AUC of furmonertinib when co-administered with telmisartan, compared to the furmonertinib-alone group. Mechanistically, it was noncompetitive in rat liver microsomes, while it was mixed competitive and noncompetitive in human liver microsomes and CYP3A4. Considering the genetic polymorphism of CYP3A4, the study further investigated its effect on the kinetics of furmonertinib. The results showed that compared to CYP3A4.1, CYP3A4.29 had significantly increased activity in catalyzing furmonertinib, whereas CYP3A4.7, 9, 10, 12, 13, 14, 18, 23, 33, and 34 showed markedly decreased activity. The inhibitory activity of telmisartan varied in CYP3A4.1 and CYP3A4.18, with IC50 values of 8.56 ± 0.90 µM and 27.48 ± 3.52 µM, respectively. The key loci affecting the inhibitory effect were identified as ARG105, ILE301, ALA370, and LEU373. Collectively, these data would provide a reference for the quantitative application of furmonertinib.

Asunto(s)

Citocromo P-450 CYP3A , Microsomas Hepáticos , Ratas Sprague-Dawley , Animales , Citocromo P-450 CYP3A/genética , Citocromo P-450 CYP3A/metabolismo , Microsomas Hepáticos/efectos de los fármacos , Microsomas Hepáticos/enzimología , Humanos , Masculino , Ratas , Polimorfismo Genético , Telmisartán/farmacología , Inhibidores del Citocromo P-450 CYP3A/farmacología , Interacciones Farmacológicas

RESUMEN

Drug metabolism in the intestinal wall affects bioavailability of orally administered drugs and is influenced by age. Hence, it is important to fully understand the drug metabolizing capacity of the gut to predict systemic exposure. The aim of this study was to investigate the potential of enteroids as a tool to study CYP3A4/5 -mediated metabolism in both children and adults. Bioconversion of midazolam, a CYP3A4/5 model substrate, was studied using enteroid monolayers as well as tissue explants in the Ussing chamber, both derived from pediatric [median (range age): 54 weeks (2 days - 13 years), n = 21] and adult (n = 5) tissue. Caco-2 cellular monolayers were employed as controls. In addition, mRNA expression of CYP3A4 was determined in enteroid monolayers (n = 11), tissue (n = 23) and Caco-2 using RT-qPCR. Midazolam metabolism was successfully detected in all enteroid monolayers, as well as in all tissue explants studied in the Ussing chamber, whereas Caco-2 showed no significant metabolite formation. The extracted fraction of midazolam was similar between enteroid monolayers and tissue. The fraction of midazolam extracted increased with age in enteroid monolayers derived from 0 to 70 week old donors. No statistically significant correlation was observed in tissue likely due to high variability observed and the smaller donor numbers included in the study. At the level of gene expression, CYP3A4 increased with age in tissues (n = 32), while this was not reflected in enteroid monolayers (n = 16). Notably, asymmetric metabolite formation was observed in enteroids and tissue, with higher metabolite formation on the luminal side of the barrier. In summary, we demonstrated that enteroids can be used to measure CYP3A4/5 midazolam metabolism, which we show is similar as observed in fresh isolated tissue. This was the case both in children and adults, indicating the potential of enteroids to predict intestinal metabolism. This study provides promising data to further develop enteroids to study drug metabolism in vitro and potentially predict oral absorption for special populations as an alternative to using fresh tissue.

Asunto(s)

Citocromo P-450 CYP3A , Midazolam , Humanos , Citocromo P-450 CYP3A/metabolismo , Citocromo P-450 CYP3A/genética , Midazolam/farmacocinética , Midazolam/metabolismo , Células CACO-2 , Niño , Preescolar , Adolescente , Lactante , Adulto , Recién Nacido , Mucosa Intestinal/metabolismo , Masculino , Organoides/metabolismo , Factores de Edad , Femenino , Intestinos , ARN Mensajero/metabolismo

RESUMEN

OBJECTIVE: This study was the first to evaluate the effect of CYP3A4 gene polymorphisms on the plasma concentration and effectiveness of perampanel (PER) in Chinese pediatric patients with epilepsy. METHODS: We enrolled 102 patients for this investigation. The steady-state concentration was determined after patients maintained a consistent PER dosing regimen for at least 21 days. Plasma PER concentrations were measured using liquid chromatography-tandem mass spectrometry. Leftover samples from standard therapeutic drug monitoring were allocated for genotyping analysis. The primary measure of efficacy was the rate of seizure reduction with PER treatment at the final check-up. RESULTS: The CYP3A4×10 GC phenotype exhibited the highest average plasma concentration of PER at 491.1 ±â€¯328.1 ng/mL, in contrast to the CC phenotype at 334.0 ±â€¯161.1 ng/mL. The incidence of adverse events was most prominent in the CYP3A4×1 G TT and CYP3A4×10 GC groups, with rates of 77.8 % (7 of 9 patients) and 50.0 % (46 of 92 patients), respectively. Moreover, the percentage of patients for whom PER was deemed ineffective was least in the CYP3A4×1 G TT and CYP3A4×10 CC groups, recorded at 11.1 % (1 of 9 patients) and 10.0 % (1 of 10 patients), respectively. There was a significant correlation between PER plasma concentration and either exposure or toxicity (both with p < 0.05). We suggest a plasma concentration range of 625-900 ng/mL as a suitable reference for PER in Chinese patients with epilepsy. CONCLUSION: The CYP3A4×10 gene's genetic polymorphisms influence plasma concentrations of PER in Chinese pediatric patients with epilepsy. Given that both efficacy and potential toxicity are closely tied to plasma PER levels, the CYP3A4 genetic phenotype should be factored in when prescribing PER to patients with epilepsy.

Asunto(s)

Anticonvulsivantes , Citocromo P-450 CYP3A , Epilepsia , Nitrilos , Piridonas , Humanos , Citocromo P-450 CYP3A/genética , Niño , Femenino , Masculino , Piridonas/farmacocinética , Piridonas/uso terapéutico , Piridonas/sangre , Epilepsia/tratamiento farmacológico , Epilepsia/genética , Anticonvulsivantes/farmacocinética , Anticonvulsivantes/uso terapéutico , Nitrilos/farmacocinética , Preescolar , Adolescente , Polimorfismo Genético/genética , China , Pueblo Asiatico/genética , Genotipo , Resultado del Tratamiento , Pueblos del Este de Asia

RESUMEN

OBJECTIVES: Rhabdomyosarcoma (RMS) accounts for 50% of soft tissue sarcomas and 7% of pediatric malignancies. Cyclophosphamide (CPA) is the cornerstone of therapy and is a prodrug that is activated by the highly polymorphic drug-metabolizing enzyme CYP3A5. We aim to examine the possible CYP3A5 polymorphism association with CPA efficacy, survival outcomes, and toxicity in Egyptian pediatric RMS patients. METHODS: The three non-functional SNPs, CYP3A5*3 rs776746 (C_26201809_30), CYP3A5*6 rs10264272 (C_30203950_10), and CYP3A5*7 rs41303343 (C_32287188_10) were genotyped by real-time PCR. We conducted a cohort retrospective study of 150 pediatric RMS patients treated with CPA-based first-line treatment to analyze the association between these genotypes and CPA efficacy/toxicities in RMS patients. KEY FINDINGS: The frequency of having normal, intermediate, and poor metabolizers was 4.7%, 34%, and 61.3%, respectively. There was an association between these different phenotypes, genotypes, and CPA efficacy/toxicity. Hemorrhagic cystitis and pancytopenia were present in all patients, while nephrotoxicity incidence was 87.3%. There was a notable difference in the occurrence of hemorrhagic cystitis among CYP3A5 intermediate metabolizers *1/*3, *1/*6, and poor metabolizers *3/*3, *3/*6 with a significance level of p<0.05. Neither CYP3A5*7 polymorphism nor *6/*6 genotype was identified in our study. CONCLUSION: Our results demonstrate that CYP3A5*3 (rs776746) and CYP3A5*6 (rs10264272) have a great association with CPA efficacy and toxicity in RMS patients.

Asunto(s)

Ciclofosfamida , Citocromo P-450 CYP3A , Polimorfismo de Nucleótido Simple , Rabdomiosarcoma , Humanos , Citocromo P-450 CYP3A/genética , Ciclofosfamida/efectos adversos , Masculino , Femenino , Rabdomiosarcoma/genética , Rabdomiosarcoma/tratamiento farmacológico , Niño , Egipto/epidemiología , Preescolar , Estudios Retrospectivos , Estudios de Seguimiento , Pronóstico , Antineoplásicos Alquilantes/efectos adversos , Antineoplásicos Alquilantes/uso terapéutico , Lactante , Genotipo , Adolescente , Tasa de Supervivencia

RESUMEN

Cytochrome P450 3A4 (CYP3A4) enzyme is involved in the metabolism of about 30 % of clinically used drugs, including the antimalarials artemether and lumefantrine. CYP3A4 polymorphisms yield enzymatic variants that contribute to inter-individual variation in drug metabolism. Here, we examined CYP3A4 polymorphisms in populations from malaria-endemic islands in Lake Victoria, Kenya, and Vanuatu, to expand on the limited data sets. We used archived dried blood spots collected from 142 Kenyan and 263 ni-Vanuatu adults during cross-sectional malaria surveys in 2013 and 2005-13, respectively, to detect CYP3A4 variation by polymerase chain reaction (PCR) and sequencing. In Kenya, we identified 14 CYP3A4 single nucleotide polymorphisms (SNPs), including the 4713G (CYP3A4∗1B; allele frequency 83.9 %) and 19382A (CYP3A4∗15; 0.7 %) variants that were previously linked to altered metabolism of antimalarials. In Vanuatu, we detected 15 SNPs, including the 4713A (CYP3A4∗1A; 88.6 %) and 25183C (CYP3A4∗18; 0.6 %) variants. Additionally, we detected a rare and novel SNP C4614T (0.8 %) in the 5' untranslated region. A higher proportion of CYP3A4 genetic variance was found among ni-Vanuatu populations (16 %) than among Lake Victoria Kenyan populations (8 %). Our work augments the scarce data sets and contributes to improved precision medicine approaches, particularly to anti-malarial chemotherapy, in East African and Pacific Islander populations.

Asunto(s)

Antimaláricos , Citocromo P-450 CYP3A , Malaria , Polimorfismo de Nucleótido Simple , Humanos , Kenia/epidemiología , Polimorfismo de Nucleótido Simple/genética , Malaria/genética , Malaria/tratamiento farmacológico , Malaria/epidemiología , Citocromo P-450 CYP3A/genética , Citocromo P-450 CYP3A/metabolismo , Vanuatu/epidemiología , Femenino , Adulto , Masculino , Enfermedades Endémicas , Estudios Transversales , Variación Genética/genética

RESUMEN

BACKGROUND: In the paediatric liver transplant programme in Johannesburg, South Africa (SA), tacrolimus is the calcineurin inhibitor of choice, comprising an essential component of the immunosuppression regimen. It is characterised by a narrow therapeutic index and wide interpatient variability, necessitating therapeutic drug monitoring of whole-blood concentrations. Pharmacogenetic research, although not representative of SA population groups, suggests that single-nucleotide polymorphisms within the cytochrome P450 3A5 (CYP3A5) gene contribute to the variability in tacrolimus dosing requirements. The rs776746 polymorphism, CYP3A5*3, results in a splice defect and a non-functional enzyme. Clinically, to reach the same tacrolimus concentration-to-dose ratio (CDR), expressors (CYP3A5*1/*1 and *1/*3) require a higher tacrolimus dose than non-expressors (*3/*3). OBJECTIVES: To compare the pharmacokinetics of tacrolimus in paediatric liver transplant recipients with their donors' CYP3A5 genotypes, considering both donor and recipient characteristics. METHODS: Blood samples from 46 living liver donors were collected, their genomic DNA was extracted, and their CYP3A5 genotype was established (polymerase chain reaction and restriction fragment length polymorphism analysis, validated by Sanger sequencing). The relationship of donor and recipient characteristics with the mean tacrolimus CDR was analysed using a general linear model. Non- confounding significant variables were included in a multiple regression model. RESULTS: The study showed that all expressor donors genotyped as CYP3A5*1/*1 were of black African self-reported race and ethnicity. During the first 15 days post-transplant, we found that children who received grafts from donor CYP3A5 expressors (CYP3A5*1/*1 and *1/*3) had significantly lower mean tacrolimus CDRs compared with those who received grafts from donor CYP3A5 non-expressors (*3/*3); the recipients of CYP3A5 expressor grafts therefore require higher doses of oral tacrolimus to achieve the same therapeutic target range. In addition, graft-to-recipient weight ratio and the CYP3A5 donor genotypes were independent factors that significantly (p<0.05) affected mean tacrolimus CDRs in recipients. CONCLUSION: In this study, we showed that all CYP3A5*1 homozygote donors were of black African self-reported race and ethnicity, and tacrolimus CDRs in paediatric living-donor liver transplant recipients were significantly affected by donor graft size and donor CYP3A5 genotypes. Information from this study may inform the development of an Afrocentric tacrolimus precision-medicine algorithm to optimise recipient safety and graft outcomes.

Asunto(s)

Citocromo P-450 CYP3A , Genotipo , Inmunosupresores , Trasplante de Hígado , Polimorfismo de Nucleótido Simple , Tacrolimus , Humanos , Tacrolimus/farmacocinética , Tacrolimus/administración & dosificación , Tacrolimus/uso terapéutico , Citocromo P-450 CYP3A/genética , Sudáfrica , Niño , Inmunosupresores/farmacocinética , Inmunosupresores/administración & dosificación , Inmunosupresores/uso terapéutico , Masculino , Femenino , Preescolar , Adolescente , Donadores Vivos , Lactante

RESUMEN

Clothianidin, classified as a second-generation neonicotinoid, has achieved extensive application due to its high efficacy against insect pests. This broad-spectrum usage has resulted in its frequent detection in environmental surveys. CYP2C19 and CYP3A4 are crucial for converting clothianidin to desmethyl-clothianidin (dm-clothianidin). The expression of these CYP450s can be significantly influenced by genetic polymorphisms. The objective of our research was to examine the catalytic effects of 27 CYP3A4 variants and 31 CYP2C19 variants on the metabolism of clothianidin within recombinant insect microsomes. These variants were assessed through a well-established incubation procedure. In addition, the concentration of its metabolite dm-clothianidin was quantified by employing an ultra performance liquid chromatography tandem mass spectrometry (UPLC-MS/MS). Lastly, the kinetic parameters of these CYP3A4 and CYP2C19 variants were calculated by applying Michaelis-Menten kinetic analysis to fit the data. The observed changes in enzyme activity were related to the metabolic transformation of clothianidin to dm-clothianidin. In the CYP2C19 metabolic pathway, one variant (CYP2C19.23) showed no notable change in intrinsic clearance (CLint), four variants (CYP2C19.29, .30, .31 and L16F) demonstrated a marked increase in CLint (110.86-183.46 %), and the remaining 25 variants exhibited a considerable decrease in CLint (26.38-89.79 %), with a maximum decrease of 73.62 % (CYP2C19.6). In the CYP3A4 metabolic pathway, 26 variants demonstrated significantly reduced CLint (10.54-52.52 %), with a maximum decrease of 89.46 % (CYP3A4.20). Our results suggested that most variants of CYP3A4 and CYP2C19 significantly altered the enzymatic activities associated with clothianidin metabolism to various degrees. This study provides new insights into assessing the metabolic behavior of pesticides and delivers crucial data that can guide clinical detoxification strategies.

Asunto(s)

Citocromo P-450 CYP2C19 , Citocromo P-450 CYP3A , Guanidinas , Neonicotinoides , Polimorfismo Genético , Tiazoles , Citocromo P-450 CYP2C19/genética , Citocromo P-450 CYP2C19/metabolismo , Citocromo P-450 CYP3A/genética , Citocromo P-450 CYP3A/metabolismo , Tiazoles/metabolismo , Guanidinas/metabolismo , Neonicotinoides/metabolismo , Humanos , Animales , Cinética , Espectrometría de Masas en Tándem , Insecticidas/metabolismo , Microsomas/metabolismo

RESUMEN

Introduction: Pharmacogenetic markers, such as the ATP Binding Cassette (ABCB1) and cytochrome P450 (CYP) 3A5 enzymes, play a crucial role in personalized medicine by influencing drug efficacy and toxicity based on individuals' or populations' genetic variations.This study aims to investigate the genetic polymorphisms of CYP3A5 (rs776746) and ABCB1 (rs1045642) in the West Algerian population and compare the genotypes and allelic distributions with those of various ethnic groups. Methods: The study involved 472 unrelated healthy subjects from the Western Algerian population. DNA genotyping was performed using TaqMan allelic discrimination assay. The variants in our population were compared to those in other ethnic groups available in the 1000 Genomes Project. Genotype and allele frequencies were calculated using the chi-square test and the Hardy-Weinberg equilibrium (HWE). Results: The minor allele frequencies were found to be 0.21 for CYP3A5 6986A and 0.34 for ABCB1 3435T. These frequencies were similar to those observed in North African populations, while notable differences were observed in comparison to certain Caucasian and African populations. Conclusion: The difference in the allelic and genotypic distribution of these polymorphisms emphasize the need for dose adjustments in drugs metabolized by CYP3A5 and transported by ABCB1 to optimize treatments outcomes.

Asunto(s)

Subfamilia B de Transportador de Casetes de Unión a ATP , Citocromo P-450 CYP3A , Frecuencia de los Genes , Genotipo , Polimorfismo de Nucleótido Simple , Humanos , Citocromo P-450 CYP3A/genética , Subfamilia B de Transportador de Casetes de Unión a ATP/genética , Argelia , Masculino , Femenino , Adulto , Farmacogenética , Persona de Mediana Edad , Población Negra/genética , Alelos , Adulto Joven

RESUMEN

BACKGROUND: The burden of chronic kidney disease (CKD) and kidney failure in Ghana is on the ascendency, with the prevalence of CKD estimated at 13.3%. Patients with CKD who progress to kidney failure require life sustaining kidney replacement therapy (KRT) which is almost exclusively available in Ghana as haemodialysis. Kidney transplantation is considered the best KRT option for patients with irreversible kidney failure due to its relative cost efficiency as well as its superiority in terms of survival and quality of life. However, because transplants may trigger an immune response with potential organ rejection, immunosuppressants such as tacrolimus dosing are required. OBJECTIVE: This study sought to determine single nucleotide polymorphisms in CYP3A5, CYP3A4 and MDR1 genes that affect the pharmacokinetics of Tacrolimus in a population of Ghanaian patients with kidney failure. METHOD: This cross-sectional study comprised of 82 kidney failure patients undergoing maintenance haemodialysis at the Renal and Dialysis unit of Korle-Bu Teaching Hospital (KBTH). Clinical and demographic data were collected and genomic DNA isolated. Samples were genotyped for specific SNPs using Polymerase Chain Reaction-Restriction Fragment Length Polymorphism (PCR-RFLP). RESULTS: Participants, 58/82 (70.73%) harbored the wildtype CYP3A5*1/*1 AA genotype, 20/82 (24.39%) carried the heterozygous CYP3A5*1/*3 AG genotype, and 4/82 (4.88%) had the homozygous mutant CYP3A5*3/*3 GG genotype. Also, 6/82 (7.32%) carried the wildtype AA genotype, 11/82 (13.41%) had the heterozygous AG genotype, and 65/82 (79.27%) harbored the homozygous mutant GG genotype of CYP3A4*1B (-290 A>G). For MDR1_Ex21 (2677 G>T), 81/82 (98.78%) carried the wildtype GG genotype, while 1/82 (1.22%) had the heterozygous GT genotype. For MDR1_Ex26 (3435 C>T), 63/82 (76.83%) had the wildtype CC genotype, while 18/82 (21.95%) carried the heterozygous CT genotype, and 1/82 (1.22%) harbored the mutant TT genotype. CONCLUSION: SNPs in CYP3A4, CYP3A5, and MDR1 genes in a population of Ghanaian kidney failure patients were described. The varying SNPs of the featured genes suggest the need to consider the genetic status of Ghanaians kidney failure patients prior to transplantation and tacrolimus therapy.

Asunto(s)

Subfamilia B de Transportador de Casetes de Unión a ATP , Citocromo P-450 CYP3A , Inmunosupresores , Polimorfismo de Nucleótido Simple , Tacrolimus , Centros de Atención Terciaria , Humanos , Polimorfismo de Nucleótido Simple/genética , Ghana/epidemiología , Femenino , Masculino , Citocromo P-450 CYP3A/genética , Tacrolimus/farmacocinética , Tacrolimus/administración & dosificación , Persona de Mediana Edad , Adulto , Subfamilia B de Transportador de Casetes de Unión a ATP/genética , Inmunosupresores/administración & dosificación , Estudios Transversales , Insuficiencia Renal/genética , Anciano , Diálisis Renal

RESUMEN

OBJECTIVE: Idiopathic inflammatory myopathies (IIM) are a heterogeneous and life-threatening group of diseases; in particular, anti-melanoma differentiation-associated gene 5 antibody positive DM (MDA5+ DM) is reportedly strongly associated with high mortality rate. Tacrolimus (TAC) provides an excellent therapeutic option, but the trough concentration (Cmin)-outcome relationship remains unexplored. This study was undertaken to identify optimal Cmin and individualized dose based on CYP3A5 genotype for IIM patients. METHODS: A total of 134 IIM patients with 467 Cmin were enrolled. We examined the relationship between TAC Cmin and relapses. The receiver operating characteristic analysis was used to confirm the optimal Cmin. Analyses of factors influencing Cmin were conducted. The dose requirement based on CYP3A5 genotype was confirmed. RESULTS: TAC Cmin is strongly associated with relapses. The optimal cutoff values were 5.30, 5.85, 4.85 and 5.35 ng/ml for acute, subacute, chronic and all-phase IIM patients (P = 0.001, 0.013, 0.002 and <0.001, respectively), as well as 5.35, 5.85, 5.55 and 5.85 ng/ml for acute, subacute, chronic and all-phase MDA5+ DM patients (P = 0.007, 0.001, 0.036 and <0.001, respectively). CYP3A5 genotype was one of the significant factors influencing TAC Cmin. CYP3A5 expressers required 0.059 mg/kg/day to attain the target Cmin, while nonexpressers required 0.046 mg/kg/day (P = 0.019). CONCLUSION: TAC treatment may elicit favorable outcome in patients with IIM and MDA5+ DM when Cmin exceeded 5.35 and 5.85 ng/ml, which is crucial to a lower relapse rate. The individualized dose based on the CYP3A5 genotype provides a reference for TAC personalized therapy in IIM.

Asunto(s)

Citocromo P-450 CYP3A , Genotipo , Inmunosupresores , Miositis , Tacrolimus , Humanos , Citocromo P-450 CYP3A/genética , Femenino , Masculino , Tacrolimus/uso terapéutico , Persona de Mediana Edad , Inmunosupresores/uso terapéutico , Adulto , Miositis/genética , Miositis/tratamiento farmacológico , Medicina de Precisión , Pueblo Asiatico/genética , China , Anciano , Recurrencia , Pueblos del Este de Asia

RESUMEN

Tacrolimus (FK506) is a cornerstone of GVHD-prophylaxis treatment in paediatrics undergoing haematopoietic stem cell transplantation (HSCT). However, due to concerns about highly inter/intra-individual variability, precision dosing of FK506 is crucial. Cytochrome P450 (CYP) 3A4 and 3A5 are considered important sources of FK506 pharmacokinetic variability. Nevertheless, the impact of age-related maturation in hepatic and intestinal CYP3A4/3A5 enzymes remains unknown in paediatric HSCT patients. Physiologically-based pharmacokinetic (PBPK) models were developed and verified in adult volunteers and adult HSCT patients using GastroPlus™ (version 9.0), and then extrapolated to paediatric HSCT patients, taking into account the maturation of CYP3A4 and CYP3A5. Default CYP3A4 and CYP3A5 ontogeny profiles were updated based on the latest reports. The paediatric PBPK model was evaluated with independent data collected from Sun Yat-sen Memorial Hospital (86 paediatric HSCT patients, 1 to 16 -year-old). Simulations were performed to evaluate a reported FK506 dosing regimen in infants and children with different CYP3A5 genotypes. Extensive PBPK model validation indicated good predictability, with the predicted/observed (P/O) ratios within the range of 0.80-fold to 1.25-fold. Blood tacrolimus concentration-time curves were comparable between the real and virtual patients. Simulations showed that the higher levels of tacrolimus in 9-month-old to 3-year-old infants were mainly attributed to the CYP3A4/3A5 ontogeny profiles, which resulted in lower clearance and higher exposure relative to dose. The oral dosage of 0.1 mg/kg/day (q12 h) is considered appropriate for paediatric HSCT patients 9 months to 15 years of age with CYP3A5 *1/*1 genotypes. Lower doses were required for paediatric HSCT patients with CYP3A5 *1/*3 (0.08 mg/kg/day, q12h) or CYP3A5 *3/*3 genotypes (0.07 mg/kg/day, q12h), and analyses demonstrated 12.5-20 % decreases in ≤3-year-old patients. The study highlights the feasibility of PBPK modelling to explore age-related enzyme maturation in infants and children (≤3-year-old) undergoing HSCT and emphasizes the need to include hepatic and gut CYP3A4/3A5 maturation parameters.

Asunto(s)

Citocromo P-450 CYP3A , Trasplante de Células Madre Hematopoyéticas , Inmunosupresores , Modelos Biológicos , Tacrolimus , Humanos , Tacrolimus/farmacocinética , Tacrolimus/administración & dosificación , Citocromo P-450 CYP3A/metabolismo , Citocromo P-450 CYP3A/genética , Niño , Preescolar , Trasplante de Células Madre Hematopoyéticas/métodos , Lactante , Adolescente , Inmunosupresores/farmacocinética , Inmunosupresores/administración & dosificación , Masculino , Femenino , Adulto