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Aryl hydrocarbon receptor (AHR) activation by tryptophan (Trp) catabolites enhances tumor malignancy and suppresses anti-tumor immunity. The context specificity of AHR target genes has so far impeded systematic investigation of AHR activity and its upstream enzymes across human cancers. A pan-tissue AHR signature, derived by natural language processing, revealed that across 32 tumor entities, interleukin-4-induced-1 (IL4I1) associates more frequently with AHR activity than IDO1 or TDO2, hitherto recognized as the main Trp-catabolic enzymes. IL4I1 activates the AHR through the generation of indole metabolites and kynurenic acid. It associates with reduced survival in glioma patients, promotes cancer cell motility, and suppresses adaptive immunity, thereby enhancing the progression of chronic lymphocytic leukemia (CLL) in mice. Immune checkpoint blockade (ICB) induces IDO1 and IL4I1. As IDO1 inhibitors do not block IL4I1, IL4I1 may explain the failure of clinical studies combining ICB with IDO1 inhibition. Taken together, IL4I1 blockade opens new avenues for cancer therapy.
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L-Aminoácido Oxidase/metabolismo , Receptores de Hidrocarboneto Arílico/metabolismo , Adulto , Idoso , Animais , Linhagem Celular , Linhagem Celular Tumoral , Progressão da Doença , Feminino , Glioma/imunologia , Glioma/metabolismo , Glioma/terapia , Células HEK293 , Humanos , Inibidores de Checkpoint Imunológico/farmacologia , Indolamina-Pirrol 2,3,-Dioxigenase/metabolismo , Leucemia Linfocítica Crônica de Células B/imunologia , Leucemia Linfocítica Crônica de Células B/metabolismo , Leucemia Linfocítica Crônica de Células B/terapia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Pessoa de Meia-Idade , RatosRESUMO
In recent years, SGLT2 inhibitors have become an integral part of heart failure therapy, and several mechanisms contributing to cardiorenal protection have been identified. In this study, we place special emphasis on the atria and investigate acute electrophysiological effects of dapagliflozin to assess the antiarrhythmic potential of SGLT2 inhibitors. Direct electrophysiological effects of dapagliflozin were investigated in patch clamp experiments on isolated atrial cardiomyocytes. Acute treatment with elevated-dose dapagliflozin caused a significant reduction of the action potential inducibility, the amplitude and maximum upstroke velocity. The inhibitory effects were reproduced in human induced pluripotent stem cell-derived cardiomyocytes, and were more pronounced in atrial compared to ventricular cells. Hypothesizing that dapagliflozin directly affects the depolarization phase of atrial action potentials, we examined fast inward sodium currents in human atrial cardiomyocytes and found a significant decrease of peak sodium current densities by dapagliflozin, accompanied by a moderate inhibition of the transient outward potassium current. Translating these findings into a porcine large animal model, acute elevated-dose dapagliflozin treatment caused an atrial-dominant reduction of myocardial conduction velocity in vivo. This could be utilized for both, acute cardioversion of paroxysmal atrial fibrillation episodes and rhythm control of persistent atrial fibrillation. In this study, we show that dapagliflozin alters the excitability of atrial cardiomyocytes by direct inhibition of peak sodium currents. In vivo, dapagliflozin exerts antiarrhythmic effects, revealing a potential new additional role of SGLT2 inhibitors in the treatment of atrial arrhythmias.
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Fibrilação Atrial , Compostos Benzidrílicos , Glucosídeos , Células-Tronco Pluripotentes Induzidas , Inibidores do Transportador 2 de Sódio-Glicose , Humanos , Animais , Suínos , Miócitos Cardíacos , Inibidores do Transportador 2 de Sódio-Glicose/farmacologia , Antiarrítmicos/farmacologia , Antiarrítmicos/uso terapêutico , Potenciais de Ação , SódioRESUMO
OBJECTIVE: To test feasibility and safety of administering sildenafil in neonates with neonatal encephalopathy (NE), developing brain injury despite therapeutic hypothermia (TH). STUDY DESIGN: We performed a randomized, double-blind, placebo-controlled phase Ib clinical trial between 2016 and 2019 in neonates with moderate or severe NE, displaying brain injury on day-2 magnetic resonance imaging (MRI) despite TH. Neonates were randomized (2:1) to 7-day sildenafil or placebo (2 mg/kg/dose enterally every 12 hours, 14 doses). Outcomes included feasibility and safety (primary outcomes), pharmacokinetics (secondary), and day-30 neuroimaging and 18-month neurodevelopment assessments (exploratory). RESULTS: Of the 24 enrolled neonates, 8 were randomized to sildenafil and 3 to placebo. A mild decrease in blood pressure was reported in 2 of the 8 neonates after initial dose, but not with subsequent doses. Sildenafil plasma steady-state concentration was rapidly reached, but decreased after TH discontinuation. Twelve percent of neonates (1/8) neonates died in the sildenafil group and 0% (0/3) in the placebo group. Among surviving neonates, partial recovery of injury, fewer cystic lesions, and less brain volume loss on day-30 magnetic resonance imaging were noted in 71% (5/7) of the sildenafil group and in 0% (0/3) of the placebo group. The rate of death or survival to 18 months with severe neurodevelopmental impairment was 57% (4/7) in the sildenafil group and 100% (3/3) in the placebo group. CONCLUSIONS: Sildenafil was safe and well-absorbed in neonates with NE treated with TH. Optimal dosing needs to be established. Evaluation of a larger number of neonates through subsequent phases II and III trials is required to establish efficacy. CLINICAL TRIAL REGISTRATION: ClinicalTrials.govNCT02812433.
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Asfixia Neonatal , Lesões Encefálicas , Hipotermia Induzida , Hipóxia-Isquemia Encefálica , Doenças do Recém-Nascido , Recém-Nascido , Humanos , Citrato de Sildenafila/efeitos adversos , Asfixia/complicações , Estudos de Viabilidade , Asfixia Neonatal/terapia , Lesões Encefálicas/complicações , Lesões Encefálicas/tratamento farmacológico , Doenças do Recém-Nascido/terapia , Hipóxia-Isquemia Encefálica/terapia , Hipotermia Induzida/métodos , Método Duplo-CegoRESUMO
Short bowel syndrome (SBS) following extensive intestinal resection is often characterized by impaired absorption of orally administered drugs, including tyrosine kinase inhibitors (TKI). We report the case of a patient with EGFR-mutated non-small cell lung carcinoma treated with 80 mg/day of the TKI osimertinib who achieved partial response of the tumour, but was subsequently subjected to a double-barrelled jejunostomy due to ileus. Due to the development of SBS after the bypass surgery, plasma concentrations of osimertinib were monitored using mass spectrometry. The therapeutic drug monitoring confirmed a malabsorption of osimertinib in the patient (108 ng/mL, which is below the 5th percentile of the expected plasma concentration) and was useful to guide adjustments of TKI dosing in order to achieve adequate blood levels (161 ng/mL after increase of the dose to 120 mg/day) in order to maintain tumour control.
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Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Síndrome do Intestino Curto , Humanos , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Carcinoma Pulmonar de Células não Pequenas/patologia , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/patologia , Síndrome do Intestino Curto/tratamento farmacológico , Monitoramento de Medicamentos , Mutação , Receptores ErbB/genética , Inibidores de Proteínas Quinases/farmacologiaRESUMO
PURPOSE: In Europe, most medicines are taken orally and primarily packaged as single solid oral dosage forms (SODF) in blister chambers (alveoli) arranged on blister cards. Blister cards are constructed as multilayer laminates of aluminum (Al) foils and/or various plastic polymers bonded together, forming the alveoli, which are separated by more or less large gaps. We calculated the amount of packaging material (and thus waste) generated annually for the packaging of the most commonly prescribed SODF in Germany and estimated how much waste could be saved by rearranging the alveoli. METHODS: For this purpose, we analysed the SODF of the 50 most frequently prescribed medicines that were packaged in alveoli (N = 45; 13 of aluminum-aluminum blisters, 32 of mixed materials), measured and weighed their packaging material and content, calculated the annual amount of waste produced from them, and estimated how much waste could be saved if the alveoli were optimally positioned on the blister cards. In addition, we examined the variability of the blister packaging of eight groups of commonly prescribed generics of the same strength. RESULTS: Detailed analysis of the blister cards revealed that most of the material (69%) was used for the space between blisters and that aluminum-aluminum alveoli were more than four times larger than the packaged SODF. The (conservatively) estimated annual amount of composite waste generated for the primary packaging of these SODF was 3868 t (and extrapolated to the entire German pharmaceutical market 8533 t), of which an optimized arrangement of the blister chambers, i.e., a 2-mm sealing area around each alveolus and the arrangement of the SODF in 2 rows, would save approximately 37%. CONCLUSION: Considering that other ecological strategies are not yet mature, the optimal arrangement of blister chambers would be a captivatingly simple and, above all, immediately implementable strategy to avoid large amounts of avoidable waste.
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Alumínio , Vesícula , Humanos , Embalagem de Medicamentos , Comprimidos , Europa (Continente)RESUMO
Rifampicin is a strong inducer of cytochrome P450 (CYP3A4) and P-glycoprotein (P-gp/ABCB1), leading to profound drug-drug interactions. In contrast, the chemically related rifabutin does not show such pronounced induction properties in vivo. The aim of our study was to conduct a comprehensive analysis of the different induction potentials of rifampicin and rifabutin in primary human hepatocytes and to analyze the mechanism of potential differences. Therefore, we evaluated CYP3A4/ABCB1 mRNA expression (polymerase chain reaction), CYP3A4/P-gp protein expression (immunoaffinity-liquid chromatography-mass spectrometry, IA-LC-MS/MS), CYP3A4 activity (testosterone hydroxylation), and considered intracellular drug uptake after treatment with increasing rifamycin concentrations (0.01-10 µM). Furthermore, rifamycin effects on the protein levels of CYP2C8, CYP2C9, and CYP2C19 were analyzed (IA-LC-MS/MS). Mechanistic analysis included the evaluation of possible suicide CYP3A4 inhibition (IC50 shift assay) and drug impact on translational efficiency (cell-free luminescence assays). Rifabutin accumulated 6- to 15-fold higher in hepatocytes than rifampicin, but induced CYP3A4 mRNA comparably to rifampicin (e. g. rifampicin 61-fold vs. rifabutin 44-fold, 72 h). While rifampicin for example enhanced protein (10 µM: 21-fold) and activity levels considerably (53-fold), rifabutin only slightly increased CYP3A4 protein expression (10 µM: 3.3-fold) or activity (11-fold) compared to rifampicin after 72 h. Both rifamycins similarly influenced expression of other eliminating proteins. A potential CYP3A4 suicide inhibition by a specific rifabutin metabolite or disruption of ribosome function were excluded experimentally. In conclusion, the lack of protein enhancement, could explain rifabutin's weaker induction-related drug-drug interaction risk in vivo.
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Citocromo P-450 CYP3A , Interações Medicamentosas , Hepatócitos , RNA Mensageiro , Rifabutina , Rifampina , Rifabutina/análogos & derivados , Rifabutina/toxicidade , Hepatócitos/efeitos dos fármacos , Hepatócitos/metabolismo , Humanos , Citocromo P-450 CYP3A/metabolismo , Citocromo P-450 CYP3A/genética , RNA Mensageiro/metabolismo , RNA Mensageiro/genética , Rifampina/farmacologia , Rifampina/toxicidade , Células Cultivadas , Indutores do Citocromo P-450 CYP3A/farmacologia , Subfamília B de Transportador de Cassetes de Ligação de ATP/genética , Subfamília B de Transportador de Cassetes de Ligação de ATP/metabolismo , Indução Enzimática/efeitos dos fármacos , Membro 1 da Subfamília B de Cassetes de Ligação de ATP/metabolismo , Membro 1 da Subfamília B de Cassetes de Ligação de ATP/genética , Masculino , Espectrometria de Massas em TandemRESUMO
Physiology-based pharmacokinetic modeling suggests that rifabutin can out-balance P-glycoprotein (P-gp) induction by concurrent P-gp inhibition. However, clinical or experimental evidence for this Janus-faced rifabutin effect is missing. Consequently, LS180 cells were exposed to a moderately (2 µM) and strongly (10 µM) P-gp-inducing concentration of rifampicin or rifabutin for 6 days. Cellular accumulation of the fluorescent P-gp substrate rhodamine 123 was evaluated using flow cytometry, either without (induction only) or with adding rifamycin drug to the cells during the rhodamine 123 efflux phase (induction + potential inhibition). Rhodamine 123 accumulation was decreased similarly by both drugs after 6-day exposure (2 µM: 55% residual fluorescence compared to non-induced cells, P < 0.01; 10 µM: 30% residual fluorescence compared to non-induced cells, P < 0.001), indicating P-gp induction. Rhodamine 123 influx transporters mRNA expressions were not affected, excluding off-target effects. Acute re-exposure to rifabutin, however, considerably re-increased rhodamine 123 accumulation (2 µM induction: re-increase by 55%, P < 0.01; 10 µM induction: 49% re-increase, P < 0.001), suggesting P-gp inhibition. In contrast, rifampicin only had weak effects (2 µM induction: no re-increase; 10 µM induction: 16% re-increase; P < 0.05). Molecular docking analysis eventually revealed that rifabutin has a higher binding affinity to the inhibitor binding site of P-gp than rifampicin (ΔG (kcal/mol) = -11.5 vs -5.3). Together, this study demonstrates that rifabutin can at least partly mask P-gp induction by P-gp inhibition, mediated by high affinity binding to the inhibitory site of P-gp.
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Rifabutina , Rifampina , Rifampina/farmacologia , Rifabutina/farmacologia , Rodamina 123/metabolismo , Membro 1 da Subfamília B de Cassetes de Ligação de ATP/metabolismo , Simulação de Acoplamento MolecularRESUMO
INTRODUCTION: We investigated the effectiveness of a multidomain intervention to preserve cognitive function in older adults at risk for dementia in Germany in a cluster-randomized trial. METHODS: Individuals with a Cardiovascular Risk Factors, Aging, and Dementia (CAIDE) risk score ≥ 9 aged 60 to 77 years were recruited. After randomization of their general practitioner (GP), patients received a multidomain intervention (including optimization of nutrition and medication, and physical, social, and cognitive activity) or general health advice and GP treatment as usual over 24 months. Primary outcome was global cognitive performance (composite z score, based on domain-specific neuropsychological tests). RESULTS: Of 1030 participants at baseline, n = 819 completed the 24-month follow-up assessment. No differences regarding global cognitive performance (average marginal effect = 0.010, 95% confidence interval: -0.113, 0.133) were found between groups at follow-up. Perceived restrictions in intervention conduct by the COVID-19 pandemic did not impact intervention effectiveness. DISCUSSION: The intervention did not improve global cognitive performance. HIGHLIGHTS: Overall, no intervention effects on global cognitive performance were detected. The multidomain intervention improved health-related quality of life in the total sample. In women, the multidomain intervention reduced depressive symptoms. The intervention was completed during the COVID-19 pandemic.
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COVID-19 , Disfunção Cognitiva , Demência , Idoso , Feminino , Humanos , Disfunção Cognitiva/epidemiologia , Disfunção Cognitiva/prevenção & controle , Demência/epidemiologia , Demência/prevenção & controle , Pandemias , Qualidade de Vida , Fatores de RiscoRESUMO
Monoclonal antibodies (mAbs) acting as immune checkpoint inhibitors (ICIs) are among the most frequently used immunotherapies in oncology. However, precision medicine approaches to adapt the treatment to the patient are still poorly exploited. Given the risk of severe adverse reactions, predicting patient eligibility for ICI therapy represents a great asset for precision medicine. Today, the extended panel of mass spectrometric approaches, accompanied by newly developed sample preparation methods is a strategy of choice for responder and non-responder stratification on a molecular basis, and early detection of resistance. In this perspective article, we review the biodisposition of mAbs, the interest in molecular stratification of patients treated with these mAbs, and the possible analytical strategies to achieve this goal, with a major emphasis on mass spectrometric approaches.
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Inibidores de Checkpoint Imunológico , Medicina de Precisão , Humanos , Inibidores de Checkpoint Imunológico/uso terapêutico , Anticorpos Monoclonais/uso terapêutico , Imunoterapia/métodos , Antígeno B7-H1RESUMO
AIMS: In patients of all ages, metamizole is a frequently used analgesic. Recently, metamizole has been identified as an inducer of, among others, cytochrome P450 (CYP) 3A activity, but the time course of this interaction has not been evaluated. METHODS: Using repeated oral microdoses (30 µg) of the CYP3A index substrate midazolam, we assessed changes in midazolam pharmacokinetics (area under the concentration-time curve from 2-4 h: AUC2-4 and estimated partial metabolic clearance: eClmet ) before, at steady-state, and after discontinuation of 3 × 1000 mg metamizole/day orally for 8 days. RESULTS: Significant changes in pharmacokinetic parameters were detected already 3 days after start of metamizole treatment. At the steady-state of enzyme induction, the geometric mean ratio of midazolam AUC2-4 was substantially reduced to 0.18 (90% confidence interval: 0.14-0.24) with a corresponding 5.43-fold (4.15-7.10) increase of eClmet . After discontinuation of metamizole, the changes slowly recovered, but were still significant at the end of the observation period on the fifth day after discontinuation of metamizole therapy (AUC2-4 reduced to 0.50 [0.41-0.63] and eClmet 1.99-fold increased [1.60-2.47, P < 0.05]). CONCLUSION: Metamizole acts as a strong inducer of CYP3A already few days after start of metamizole administration and, thus, should be avoided in patients using drugs with narrow therapeutic index and major clearance via CYP3A. If their administration is essential, close monitoring and dose adjustment of comedication should be performed as early as the first week after the initiation and after discontinuation of metamizole therapy.
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Dipirona , Midazolam , Humanos , Midazolam/farmacocinética , Dipirona/farmacologia , Citocromo P-450 CYP3A/metabolismo , Voluntários Saudáveis , Cinética , Área Sob a Curva , Interações Medicamentosas , Administração OralRESUMO
PURPOSE: We assessed the differential effect of clarithromycin, a strong inhibitor of cytochrome P450 (CYP) 3A4 and P-glycoprotein, on the pharmacokinetics of a regular dose of edoxaban and on a microdose cocktail of factor Xa inhibitors (FXaI). Concurrently, CYP3A activity was determined with a midazolam microdose. METHODS: In an open-label fixed-sequence trial in 12 healthy volunteers, the pharmacokinetics of a microdosed FXaI cocktail (µ-FXaI; 25 µg apixaban, 50 µg edoxaban, and 25 µg rivaroxaban) and of 60 mg edoxaban before and during clarithromycin (2 x 500 mg/d) dosed to steady-state was evaluated. Plasma concentrations of study drugs were quantified using validated ultra-performance liquid chromatography-tandem mass spectrometry methods. RESULTS: Therapeutic clarithromycin doses increased the exposure of a therapeutic 60 mg dose of edoxaban with a geometric mean ratio (GMR) of the area under the plasma concentration-time curve (AUC) of 1.53 (90 % CI: 1.37-1.70; p < 0.0001). Clarithromycin also increased the GMR (90% CI) of the exposure of microdosed FXaI apixaban to 1.38 (1.26-1.51), edoxaban to 2.03 (1.84-2.24), and rivaroxaban to 1.44 (1.27-1.63). AUC changes observed for the therapeutic edoxaban dose were significantly smaller than those observed with the microdose (p < 0.001). CONCLUSION: Clarithromycin increases FXaI exposure. However, the magnitude of this drug interaction is not expected to be clinically relevant. The edoxaban microdose overestimates the extent of the drug interaction with the therapeutic dose, whereas AUC ratios for apixaban and rivaroxaban were comparable to the interaction with therapeutic doses as reported in the literature. TRIAL REGISTRATION: EudraCT Number: 2018-002490-22.
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PURPOSE: Early antiviral treatment with nirmatrelvir/ritonavir is recommended for SARS-CoV-2-infected patients at high risk for severe courses. Such patients are usually chronically ill and susceptible to adverse drug interactions caused by ritonavir. We investigated the interactions of short-term low-dose ritonavir therapy with atorvastatin and rosuvastatin, two statins commonly used in this population. METHOD: We assessed exposure changes (area under the concentration-time curve (AUC∞) and maximum concentration (Cmax)) of a single dose of 10 mg atorvastatin and 10 mg rosuvastatin before and on the fifth day of ritonavir treatment (2 × 100 mg/day) in healthy volunteers and developed a semi-mechanistic pharmacokinetic model to estimate dose adjustment of atorvastatin during ritonavir treatment. RESULTS: By the fifth day of ritonavir treatment, the AUC∞ of atorvastatin increased 4.76-fold and Cmax 3.78-fold, and concurrently, the concentration of atorvastatin metabolites decreased to values below the lower limit of quantification. Pharmacokinetic modelling indicated that a stepwise reduction in atorvastatin dose during ritonavir treatment with a stepwise increase up to 4 days after ritonavir discontinuation can keep atorvastatin exposure within safe and effective margins. Rosuvastatin pharmacokinetics were only mildly modified; ritonavir significantly increased the Cmax 1.94-fold, while AUC∞ was unchanged. CONCLUSION: Atorvastatin doses should likely be adjusted during nirmatrelvir/ritonavir treatment. For patients on a 20-mg dose, we recommend half of the original dose. In patients taking 40 mg or more, a quarter of the dose should be taken until 2 days after discontinuation of nirmatrelvir/ritonavir. Patients receiving rosuvastatin do not need to change their treatment regimen. TRIAL REGISTRATION: EudraCT number: 2021-006634-39. DRKS00027838.
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AIMS: Alcohol-associated liver disease (ALD) is a global health problem caused, among other factors, by oxidative stress from the formation of reactive oxygen species (ROS). One important source of ROS is microsomal ethanol metabolism catalyzed by cytochrome P450 2E1 (CYP2E1), which is induced by chronic ethanol consumption. Inhibition of CYP2E1 by clomethiazole (CMZ) decreases oxidative stress in cell cultures and improves ALD in animal studies. Our study aimed to assess the benefits of a CYP2E1 inhibitor (clomethiazole) in detoxification of patients with ALD. METHODS: Open label, randomized controlled clinical trial to study whether CYP2E1 inhibition improves ALD in the patients with alcohol use disorders admitted for alcohol detoxification therapy (ADT). Patients had to have a serum aspartate aminotransferase (AST) activity exceeding twice the upper normal limit at time of admission and be non-cirrhotic defined by fibroscan value <12 kPa. Sixty patients were randomly assigned to ADT with either CMZ or clorazepate (CZP) for 7-10 days in a 1:1 ratio. The chlorzoxazone test of CYP2E1 activity was performed at enrolment and at 2 points during the study. RESULTS: ADT improved hepatic steatosis (controlled attenuation parameter) in both groups significantly. A trend towards a greater improvement in hepatic fat content during ADT (-21.5%) was observed in the CMZ group (252 ± 48 dB/m vs. 321 ± 38 dB/m; P < 0.0001) compared with the CZP group (-13.9%; 273 ± 38 dB/m vs. 317 ± 39 dB/m; P < 0.0001). As already reported, serum AST (P < 0.004) and alanine aminotransferase (ALT) activities (P < 0.0006) significantly decreased in CMZ patients as compared with patients on CZP by the end of hospitalization. A significant correlation was found between AST (P = 0.023), ALT (P = 0.009), GGT (P = 0.039) and CAP. CONCLUSION: This study demonstrates that CMZ improves clinical biomarkers for ALD in humans most likely due to its inhibitory effect on CYP2E1. Because of its addictive potential, CMZ can only be given for a short period of time and therefore other CYP2E1 inhibitors to treat ALD are needed.
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Alcoolismo , Fígado Gorduroso , Hepatopatias Alcoólicas , Animais , Humanos , Clormetiazol/metabolismo , Clormetiazol/farmacologia , Clorazepato Dipotássico , Citocromo P-450 CYP2E1 , Alcoolismo/metabolismo , Espécies Reativas de Oxigênio , Fígado , Hepatopatias Alcoólicas/metabolismo , Etanol/farmacologia , Transaminases/metabolismo , Transaminases/farmacologia , Alanina TransaminaseRESUMO
Compared to rifampicin (600 mg/day), standard doses of rifabutin (300 mg/day) have a lower risk of drug-drug interactions due to induction of cytochrome P450 3A4 (CYP3A4) or P-glycoprotein (Pgp/ABCB1) mediated by the pregnane X receptor (PXR). However, clinical comparisons with equal rifamycin doses or in vitro experiments respecting actual intracellular concentrations are lacking. Thus, the genuine pharmacological differences and the potential molecular mechanisms of the discordant perpetrator effects are unknown. Consequently, the cellular uptake kinetics (mass spectrometry), PXR activation (luciferase reporter gene assays), and impact on CYP3A4 and Pgp/ABCB1 expression and activity (polymerase chain reaction, enzymatic assays, flow cytometry) were evaluated in LS180 cells after treatment with different rifampicin or rifabutin concentrations for variable exposure times and eventually normalized to actual intracellular concentrations. In addition, inhibitory effects on CYP3A4 and Pgp activities were investigated. While rifampicin is poorly taken up by LS180 cells, it strongly activates PXR and leads to enhanced expression and activity of CYP3A4 and Pgp. In contrast, rifabutin is a significantly less potent and less efficient PXR activator and gene inducer, despite sixfold to eightfold higher intracellular accumulation. Finally, rifabutin is a potent inhibitor of Pgp (IC50 = 0.3 µM) compared to rifampicin (IC50 = 12.9 µM). Together, rifampicin and rifabutin significantly differ by their effects on the regulation and function of CYP3A4 and Pgp, even when controlled for intracellular concentrations. Rifabutin's concurrent Pgp inhibitory action might partly compensate the inducing effects, explaining its weaker clinical perpetrator characteristics.
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Receptores de Esteroides , Rifampina , Rifampina/farmacologia , Citocromo P-450 CYP3A/genética , Citocromo P-450 CYP3A/metabolismo , Rifabutina/toxicidade , Receptores de Esteroides/genética , Receptores de Esteroides/metabolismo , Interações MedicamentosasRESUMO
The authors would like to make the following corrections to the publication [...].
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The development of desorption/ionization (DI) mass spectrometric (MS) assays for drug quantification in tissue sections and their validation according to regulatory guidelines would enable their universalization for applications in (clinical) pharmacology. Recently, new enhancements in desorption electrospray ionization (DESI) have highlighted the reliability of this ion source for the development of targeted quantification methods that meet requirements for method validation. However, it is necessary to consider subtle parameters leading to the success of such method developments, such as the morphology of desorption spots, the analytical time, and sample surface, to cite but a few. Here, we provide additional experimental data highlighting an additional important parameter, based on the unique advantage of DESI-MS on continuous extraction during analysis. We demonstrate that considering desorption kinetics during DESI analyses would largely help (i) reducing analytical time during profiling analyses, (ii) verifying solvent-based drug extraction using the selected sample preparation method for profiling and imaging modes, and (iii) predicting the feasibility of imaging assays using samples in a given expected concentration range of the targeted drug. These observations will likely serve as precious guidance for the development of validated DESI-profiling and imaging methods in the future.
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Diagnóstico por Imagem , Espectrometria de Massas por Ionização por Electrospray , Espectrometria de Massas por Ionização por Electrospray/métodos , Reprodutibilidade dos Testes , CinéticaRESUMO
PURPOSE: The use of two-dimensional (2D) printing technologies of drugs on orodispersible films (ODF) can promote dose individualization and facilitate drug delivery in vulnerable patients, including children. We investigated midazolam pharmacokinetics after the administration of 2D-printed ODF. METHODS: Midazolam doses of 0.03 and 3 mg were printed on an ODF using a 2D drug printer. We investigated the bioavailability of the two midazolam doses with ODF swallowed immediately (ODF-IS) or delayed after 2 min (ODF-DS) by comparing their pharmacokinetics with intravenous and oral midazolam solution in 12 healthy volunteers. RESULTS: The relative bioavailability of ODF-IS 0.03 mg was 102% (90% confidence interval: 89.4-116) compared to oral solution and for 3 mg 101% (86.8-116). Cmax of ODF-IS 0.03 mg was 95.5% (83.2-110) compared to oral solution and 94.3% (78.2-114) after 3 mg. Absolute bioavailability of ODF-IS 0.03 mg was 24.9% (21.2-29.2) and for 3 mg 28.1% (23.4-33.8) (oral solution: 0.03 mg: 24.4% (22.0-27.1); 3 mg: 28.0% (25.0-31.2)). Absolute bioavailability of ODF-DS was significantly larger than for ODF-IS (0.03 mg: 61.4%; 3 mg: 44.1%; both p < 0.0001). CONCLUSION: This trial demonstrates the tolerability and unchanged bioavailability of midazolam printed on ODF over a 100-fold dose range, proving the suitability of ODF for dose individualization. Midazolam ODF-IS AUC0-∞ in both doses was bioequivalent to the administration of an oral solution. However, Cmax of the therapeutic dose of ODF-IS missed bioequivalence by a clinically not relevant extent. Prolonged mucosal exposure increased bioavailability. (Trial Registration EudraCT: 2020-003984-24, August 10, 2020).
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Midazolam , Criança , Humanos , Administração Oral , Disponibilidade Biológica , Voluntários Saudáveis , Equivalência TerapêuticaRESUMO
PURPOSE: To describe the prevalence of complexity factors in the medication regimens of community-dwelling patients with more than five drugs and to evaluate the relevance of these factors for individual patients. METHODS: Data were derived from the HIOPP-6 trial, a controlled study conducted in 9 general practices which evaluated an electronic tool to detect and reduce complexity of drug treatment. The prevalence of complexity factors was based on the results of the automated analysis of 139 patients' medication data. The relevance assessment was based on the patients' rating of each factor in an interview (48 patients included for analysis). RESULTS: A median of 5 (range 0-21) complexity factors per medication regimen were detected and at least one factor was observed in 131 of 139 patients. Almost half of these patients found no complexity factor in their medication regimen relevant. CONCLUSION: In most medication regimens, complexity factors could be identified automatically, yet less than 15% of factors were indeed relevant for patients as judged by themselves. When assessing complexity of medication regimens, one should especially consider factors that are both particularly frequent and often challenging for patients, such as use of inhalers or tablet splitting. TRIAL REGISTRATION: The HIOPP-6 trial was registered retrospectively on May 17, 2021, in the German Clinical Trials register under DRKS-ID DRKS00025257.
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Vida Independente , Polimedicação , Protocolos Clínicos , Humanos , Prevalência , Estudos RetrospectivosRESUMO
The activity of nuclear receptors (e.g., pregnane x receptor, PXR) can be assessed by luminescence-based dual reporter gene assays. Under most conditions, receptor-activated firefly luminescence is normalized to Renilla luminescence, which is triggered by a constitutively active promoter. Simultaneous damage to the cells can however disrupt these signals and thus impair the interpretation of the data. Consequently, this study addressed three important aspects: First, idealized models were described, each highlighting crucial characteristics and important pitfalls of dual PXR reporter gene assays used to evaluate PXR activation or inhibition. Second, these models were supported by experimental data obtained with a strong PXR activator (rifampicin) with low cytotoxicity, a PXR activator with high cytotoxicity (dovitinib), a proposed PXR inhibitor that reportedly has no toxic effects (triptolide), and a cytotoxic control (oxaliplatin). Data were evaluated for relative PXR activity data, individual firefly or Renilla luminescence, and anti-proliferative effects of the compounds (assessed by crystal violet staining). Finally, a step-by-step guide is proposed to avoid misleading set-up of the assay or misinterpretation of the data obtained. Key considerations here include (1) omission of drug concentrations beyond 10-20% proliferation inhibition; (2) observation of Renilla luminescence, because this tends to indicate 'false PXR activation' when it inexplicably decreases; (3) parallel decrease of relative PXR activity and proliferation below baseline levels in conjunction with a sharp decrease in Renilla luminescence indicates 'false PXR antagonism'; (4) non-sigmoidal relationships suggest the absence of concentration dependency.
Assuntos
Receptores de Esteroides , Citocromo P-450 CYP3A/genética , Genes Reporter , Receptores Citoplasmáticos e Nucleares/genética , Receptores de Esteroides/genética , Rifampina/farmacologiaRESUMO
BACKGROUND: Pharmacist-led medication review and medication management programs (MMP) are well-known strategies to improve medication safety and effectiveness. If performed interprofessionally, outcomes might even improve. However, little is known about task sharing in interprofessional MMP, in which general practitioners (GPs) and community pharmacists (CPs) collaboratively perform medication reviews and continuously follow-up on patients with designated medical and pharmaceutical tasks, respectively. In 2016, ARMIN (Arzneimittelinitiative Sachsen-Thüringen) an interprofessional MMP was launched in two German federal states, Saxony and Thuringia. The aim of this study was to understand how GPs and CPs share tasks in MMP when reviewing the patients' medication. METHODS: This was a cross-sectional postal survey among GPs and CPs who participated in the MMP. Participants were asked who completed which MMP tasks, e.g., checking drug-drug interactions, dosing, and side effects. In total, 15 MMP tasks were surveyed using a 5-point Likert scale ranging from "I complete this task alone" to "GP/CP completes this task alone". The study was conducted between 11/2020 and 04/2021. Data was analyzed using descriptive statistics. RESULTS: In total, 114/165 (69.1%) GPs and 166/243 (68.3%) CPs returned a questionnaire. The majority of GPs and CPs reported (i) checking clinical parameters and medication overuse and underuse to be completed by GPs, (ii) checking storage conditions of drugs and initial compilation of the patient's medication including brown bag review being mostly performed by CPs, and (iii) checking side-effects, non-adherence, and continuous updating of the medication list were carried out jointly. The responses differed most for problems with self-medication and adding and removing over-the-counter medicines from the medication list. In addition, the responses revealed that some MMP tasks were not sufficiently performed by either GPs or CPs. CONCLUSIONS: Both GPs' and CPs' expertise are needed to perform MMP as comprehensively as possible. Future studies should explore how GPs and CPs can complement each other in MMP most efficiently.