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1.
Drug Metab Dispos ; 49(9): 736-742, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34135088

RESUMO

Inconsistencies in pharmacokinetic parameters between individual animals in preclinical studies are a common occurrence. Often such differences between animals are simply accepted as experimental variability rather than as indications of specific differences in animal phenotype that could lead to a different interpretation of the data. The fraction unbound in plasma is one factor influencing pharmacokinetic parameters and is typically determined using pooled plasma from multiple animals, making the assumption that there is limited population variance. However, this assumption is not often tested and may not hold true if there are polymorphisms affecting binding or variation in the concentrations of individual plasma proteins that could give rise to different fraction unbound phenotypes in individual animals. During profiling of a novel Syk inhibitor, AZ8399, striking interindividual differences in total plasma clearance and volume of distribution were observed between dogs consistent with differences in fraction unbound between animals. Determination of the fraction unbound showed a ∼5-fold difference in fraction unbound between the animals in the study. Broader analysis of individual dogs across a colony demonstrated a correlation between individual animal fraction unbound with total plasma clearance and volume of distribution. The concentrations of the common drug-binding proteins albumin and α1-acid glycoprotein in plasma were determined, and α1-acid glycoprotein levels were found to correlate with fraction unbound. Finally, single-nucleotide polymorphisms were identified at c.502 and c.522 of exon 5 of the dog α1-acid glycoprotein gene that may be correlated to the α1-acid glycoprotein concentration phenotype observed. SIGNIFICANCE STATEMENT: The current work demonstrates the potential for significant interindividual differences in plasma fraction unbound in beagle dogs and goes on to examine the underlying cause for the compound described. The findings suggest that the application of a population mean value of fraction unbound generated from a pooled sample may not always be appropriate and could introduce significant errors in scaling of in vitro clearance values, PBPK understanding, and interpretation of PKPD or toxicokinetic data in the context of unbound concentrations.


Assuntos
Inibidores Enzimáticos , Orosomucoide , Ligação Proteica , Quinase Syk , Animais , Proteínas Sanguíneas/análise , Proteínas Sanguíneas/metabolismo , Cães , Desenvolvimento de Medicamentos/métodos , Inibidores Enzimáticos/sangue , Inibidores Enzimáticos/farmacocinética , Estudos de Associação Genética , Taxa de Depuração Metabólica , Orosomucoide/genética , Orosomucoide/metabolismo , Variantes Farmacogenômicos , Polimorfismo de Nucleotídeo Único , Ligação Proteica/efeitos dos fármacos , Ligação Proteica/fisiologia , Especificidade da Espécie , Quinase Syk/antagonistas & inibidores , Quinase Syk/metabolismo
2.
FASEB J ; 34(5): 6808-6823, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32239698

RESUMO

Asymmetric dimethylarginine (ADMA), an endogenous inhibitor and uncoupler of nitric oxide synthase, has gained attention as a risk factor for cardiac disease, metabolic syndrome, and cerebrovascular disease. In this study, we investigated the role of systemic ADMA overburden in cerebromicrovascular pathology associated with cognitive dysfunction using APPSwDI transgenic mice expressing human ß-amyloid precursor protein Swedish (Tg-SwDI), a model of cerebrovascular ß-amyloidosis. To induce systemic overburden of ADMA, Tg-SwDI mice were treated with a daily dose of exogenous ADMA. ADMA treatment resulted in elevated ADMA levels in the blood and brain of Tg-SwDI mice. ADMA treatment induced the brain nitrosative stress and inflammation as well as enhanced the brain Aß deposition and cognitive impairment in Tg-SwDI mice. However, ADMA treatment had no such effects on wild type mice. ADMA treatment also exacerbated brain microvascular pathology in Tg-SwDI mice as observed by increased blood-brain barrier dysfunction, loss of tight junction proteins, increased endothelial stress fibers, and decreased microvessel density in the brain. In addition, similar observations were made in cultured human brain microvessel endothelial cells, where ADMA in the presence of VEGF-induced endothelial cell signaling for F-actin stress fiber inducing endothelial barrier dysfunction. Overall, these data document the potential role of ADMA in the cognitive pathology under conditions of cerebrovascular ß-amyloidosis.


Assuntos
Precursor de Proteína beta-Amiloide/fisiologia , Arginina/análogos & derivados , Transtornos Cerebrovasculares/fisiopatologia , Disfunção Cognitiva/patologia , Endotélio Vascular/patologia , Inibidores Enzimáticos/toxicidade , Animais , Arginina/sangue , Arginina/toxicidade , Disfunção Cognitiva/etiologia , Disfunção Cognitiva/metabolismo , Inibidores Enzimáticos/sangue , Feminino , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Camundongos Transgênicos
3.
Anal Bioanal Chem ; 413(25): 6225-6237, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34406463

RESUMO

The presence of reduced aminothiols, including homocysteine (Hcy), cysteine (Cys), cysteinyl-glycine (CG), and glutathione (GSH), is significantly increased in the pathological state. However, there have been no reports on the relationship between reduced aminothiols (Hcy, Cys, CG, and GSH) and different genders, ages, and drug combinations in human blood. The accurate quantification of these reduced thiols in biological fluids is important for monitoring some special pathological conditions of humans. However, the published methods typically not only require cumbersome and technically challenging processing procedures to ensure reliable measurements, but are also laborious and time-consuming, which may disturb the initial physiological balance and lead to inaccurate results. We developed a hollow fiber centrifugal ultrafiltration (HFCF-UF) method for sample preparation coupled with a high-performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS) method and used it to determine four reduced aminothiols (Hcy, Cys, CG, and GSH) in human blood for the first time. A total of 96 clinical patients were enrolled in our study. The influence of different genders, ages, and drug combinations on the levels of four reduced thiols in human blood was also discussed by SPSS 24.0. The sample preparation was simplified to a single 5 min centrifugation step in a sealed system that did not disturb the physiological environment. The validation parameters for the methodological results were excellent. The procedure was successfully applied to monitoring the concentrations of four reduced aminothiols (Hcy, Cys, CG, and GSH) in 96 clinical blood samples. There were no significant differences in Hcy, Cys, CG, or GSH for the different genders, ages, or combinations with methotrexate or vancomycin (P > 0.05). However, there was a significant increase in Hcy concentration in patients treated with valproic acid who were diagnosed with epilepsy (p=0.0007). It is advisable to measure reduced Hcy level in patients taking valproic acid. The developed HFCF-UF method was simple and accurate. It can be easily applied in clinical research to evaluate oxidative stress in further study.


Assuntos
Análise Química do Sangue/métodos , Cisteína/sangue , Dipeptídeos/sangue , Glutationa/sangue , Homocisteína/sangue , Ultrafiltração/métodos , Antibacterianos/sangue , Antibacterianos/química , Cromatografia Líquida de Alta Pressão/métodos , Cisteína/química , Dipeptídeos/química , Inibidores Enzimáticos/sangue , Inibidores Enzimáticos/química , Congelamento , Glutationa/química , Homocisteína/química , Humanos , Limite de Detecção , Metotrexato/sangue , Metotrexato/química , Estrutura Molecular , Espectrometria de Massas em Tandem/métodos , Temperatura , Ácido Valproico/sangue , Ácido Valproico/química , Vancomicina/sangue , Vancomicina/química
4.
Biomed Chromatogr ; 35(2): e4968, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-32881002

RESUMO

In this study, a simple and sensitive UHPLC-ESI-MS/MS method was established for the determination of LXH254 in rat plasma. The developed method was validated according to the Food and Drug administration guidelines. After extraction using ethyl acetate, the sample was separated on an ACQUITY BEH C18 column. The mobile phase consisted of 2 mM ammonium acetate containing 0.1% formic acid and acetonitrile as the mobile phase with gradient elution. The flow rate was 0.3 mL/min. A TSQ triple quadrupole mass spectrometer operated in positive-ion mode was used for mass detection, with multiple reaction monitoring transitions of m/z 503.3 > 459.1 and m/z 435.3 > 367.1 for LXH254 and olaparib (internal standard), respectively. An excellent linearity was achieved in the concentration range of 0.1-1000 ng/mL, with correlation coefficient >0.998. The mean recovery was more than 78.55%. Inter- and intra-day precision (percentage of relative standard deviation) did not exceed 12.87%, and accuracy was in the range of -2.50 to 13.50%. LXH254 was demonstrated to be stable under the tested storage conditions. The validated UHPLC-MS/MS method was further applied to the pharmacokinetic study of LXH254 in rat plasma after oral (2, 5, and 15 mg/kg) and intravenous (2 mg/kg) administrations. The pharmacokinetic study revealed that LXH254 showed low clearance, moderate bioavailability (~30%), and linear pharmacokinetic profile over the oral dose range of 2-15 mg/kg. To the best of our knowledge, this is the first report on the method development and validation of the determination of LXH254 and its application to pharmacokinetic study.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Inibidores Enzimáticos/sangue , Inibidores Enzimáticos/farmacocinética , Espectrometria de Massas em Tandem/métodos , Quinases raf/antagonistas & inibidores , Administração Intravenosa , Administração Oral , Animais , Disponibilidade Biológica , Estabilidade de Medicamentos , Inibidores Enzimáticos/administração & dosagem , Inibidores Enzimáticos/química , Modelos Lineares , Masculino , Niacinamida/análogos & derivados , Ratos , Ratos Sprague-Dawley , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
5.
Molecules ; 26(19)2021 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-34641489

RESUMO

Nitisinone (NTBC) is used in the treatment of disorders affecting the tyrosine pathway, including hereditary tyrosinemia type I, alkaptonuria, and neuroblastoma. An inappropriate dosage of this therapeutic drug causes side effects; therefore, it is necessary to develop a rapid and sensitive method to monitor the content of NTBC in patients' blood. This study aimed to develop anew polymeric sorbent containing ß-cyclodextrin (ß-CD) derivatives grafted on silica gel to effectively extract NTBC from model physiological fluids. The inclusion complex formed between ß-CD and NTBC was examined by proton nuclear magnetic resonance spectroscopy. The novel sorbents with derivatives of ß-CD were prepared on modified silica gel using styrene as a comonomer, ethylene glycol dimethacrylate as a crosslinking agent, and 2,2'-azo-bis-isobutyronitrile as a polymerization initiator. The obtained products were characterized via Fourier transform infrared spectroscopy and then used as sorbents as part of a solid phase extraction technique. High NTBC recovery (70%indicated that the developed polymeric sorbent may be suitable for extracting this compound from patients' blood samples.


Assuntos
Cicloexanonas/isolamento & purificação , Inibidores Enzimáticos/isolamento & purificação , Nitrobenzoatos/isolamento & purificação , Polímeros/química , Sílica Gel/química , Dióxido de Silício/química , Extração em Fase Sólida/métodos , beta-Ciclodextrinas/química , Adsorção , Cicloexanonas/sangue , Inibidores Enzimáticos/sangue , Humanos , Nitrobenzoatos/sangue , Polimerização
6.
J Pharmacol Exp Ther ; 372(3): 339-353, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-31818916

RESUMO

The serine hydrolase monoacylglycerol lipase (MAGL) is the rate-limiting enzyme responsible for the degradation of the endocannabinoid 2-arachidonoylglycerol (2-AG) into arachidonic acid and glycerol. Inhibition of 2-AG degradation leads to elevation of 2-AG, the most abundant endogenous agonist of the cannabinoid receptors (CBs) CB1 and CB2. Activation of these receptors has demonstrated beneficial effects on mood, appetite, pain, and inflammation. Therefore, MAGL inhibitors have the potential to produce therapeutic effects in a vast array of complex human diseases. The present report describes the pharmacologic characterization of [1-(4-fluorophenyl)indol-5-yl]-[3-[4-(thiazole-2-carbonyl)piperazin-1-yl]azetidin-1-yl]methanone (JNJ-42226314), a reversible and highly selective MAGL inhibitor. JNJ-42226314 inhibits MAGL in a competitive mode with respect to the 2-AG substrate. In rodent brain, the compound time- and dose-dependently bound to MAGL, indirectly led to CB1 occupancy by raising 2-AG levels, and raised norepinephrine levels in cortex. In vivo, the compound exhibited antinociceptive efficacy in both the rat complete Freund's adjuvant-induced radiant heat hypersensitivity and chronic constriction injury-induced cold hypersensitivity models of inflammatory and neuropathic pain, respectively. Though 30 mg/kg induced hippocampal synaptic depression, altered sleep onset, and decreased electroencephalogram gamma power, 3 mg/kg still provided approximately 80% enzyme occupancy, significantly increased 2-AG and norepinephrine levels, and produced neuropathic antinociception without synaptic depression or decreased gamma power. Thus, it is anticipated that the profile exhibited by this compound will allow for precise modulation of 2-AG levels in vivo, supporting potential therapeutic application in several central nervous system disorders. SIGNIFICANCE STATEMENT: Potentiation of endocannabinoid signaling activity via inhibition of the serine hydrolase monoacylglycerol lipase (MAGL) is an appealing strategy in the development of treatments for several disorders, including ones related to mood, pain, and inflammation. [1-(4-Fluorophenyl)indol-5-yl]-[3-[4-(thiazole-2-carbonyl)piperazin-1-yl]azetidin-1-yl]methanone is presented in this report to be a novel, potent, selective, and reversible noncovalent MAGL inhibitor that demonstrates dose-dependent enhancement of the major endocannabinoid 2-arachidonoylglycerol as well as efficacy in models of neuropathic and inflammatory pain.


Assuntos
Encéfalo/efeitos dos fármacos , Inibidores Enzimáticos/farmacologia , Leucócitos Mononucleares/efeitos dos fármacos , Monoacilglicerol Lipases/antagonistas & inibidores , Piperazinas/farmacologia , Animais , Ligação Competitiva , Encéfalo/enzimologia , Relação Dose-Resposta a Droga , Inibidores Enzimáticos/sangue , Escherichia coli/enzimologia , Escherichia coli/genética , Células HeLa , Humanos , Cinética , Leucócitos Mononucleares/enzimologia , Masculino , Camundongos Endogâmicos C57BL , Estrutura Molecular , Monoacilglicerol Lipases/genética , Dor/tratamento farmacológico , Piperazinas/sangue , Ligação Proteica , Ratos Sprague-Dawley , Receptor CB1 de Canabinoide/agonistas , Receptor CB2 de Canabinoide/agonistas , Sono REM/efeitos dos fármacos , Especificidade por Substrato
7.
Toxicol Appl Pharmacol ; 401: 115103, 2020 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-32522582

RESUMO

Small cell lung cancer (SCLC) is a particularly aggressive subset of lung cancer, and identification of new therapeutic options is of significant interest. We recently reported that SCLC cell lines display a specific vulnerability to inhibition of squalene epoxidase (SQLE), an enzyme in the cholesterol biosynthetic pathway that catalyzes the conversion of squalene to 2,3-oxidosqualene. Since it has been reported that SQLE inhibition can result in dermatitis in dogs, we conducted a series of experiments to determine if SQLE inhibitors would be tolerated at exposures predicted to drive maximal efficacy in SCLC tumors. Detailed profiling of the SQLE inhibitor NB-598 showed that dogs did not tolerate predicted efficacious exposures, with dose-limiting toxicity due to gastrointestinal clinical observations, although skin toxicities were also observed. To extend these studies, two SQLE inhibitors, NB-598 and Cmpd-4″, and their structurally inactive analogs, NB-598.ia and Cmpd-4″.ia, were profiled in monkeys. While both active SQLE inhibitors resulted in dose-limiting gastrointestinal toxicity, the structurally similar inactive analogs did not. Collectively, our data demonstrate that significant toxicities arise at exposures well below the predicted levels needed for anti-tumor activity. The on-target nature of the toxicities identified is likely to limit the potential therapeutic utility of SQLE inhibition for the treatment of SCLC.


Assuntos
Inibidores Enzimáticos/sangue , Inibidores Enzimáticos/toxicidade , Esqualeno Mono-Oxigenase/antagonistas & inibidores , Esqualeno Mono-Oxigenase/sangue , Animais , Cães , Relação Dose-Resposta a Droga , Avaliação Pré-Clínica de Medicamentos/métodos , Macaca fascicularis , Masculino , Pele/efeitos dos fármacos , Pele/enzimologia , Pele/patologia
8.
Semin Liver Dis ; 39(4): 414-421, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31041787

RESUMO

To prevent rejection, liver transplant providers largely base their management decisions on their clinical impression and pharmacokinetics. Clinical impression relies on assessing graft function, liver enzymes, and biopsy. High immunosuppressive drug levels, although minimizing rejection, are related to significant side effects such as nephrotoxicity and metabolic syndrome, contributing to long-term morbidity and mortality. Similarly, levels that are lower than necessary can decrease the rate of side effects with a potential toll on rejection and graft survival. Herein, the authors present an update on immunosuppressive drug level monitoring and manipulation strategies according to different scenarios and time from transplant. They also provide a brief overview of next level immunosuppression monitoring strategies that aim to properly balance rejection rates with drug side effect profiles.


Assuntos
Tomada de Decisão Clínica , Imunossupressores/sangue , Transplante de Fígado , Transplantados , Inibidores de Calcineurina/administração & dosagem , Inibidores de Calcineurina/sangue , Interações Medicamentosas , Monitoramento de Medicamentos , Inibidores Enzimáticos/administração & dosagem , Inibidores Enzimáticos/sangue , Rejeição de Enxerto/prevenção & controle , Sobrevivência de Enxerto , Humanos , Imunossupressores/administração & dosagem , Imunossupressores/efeitos adversos , Serina-Treonina Quinases TOR/antagonistas & inibidores
9.
Ther Drug Monit ; 41(6): 703-713, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31219949

RESUMO

BACKGROUND: Mycophenolate mofetil or enteric-coated mycophenolate sodium (EC-MPS) and steroids are used for induction and maintenance therapy in severe lupus nephritis. Blood concentrations of mycophenolic acid (MPA), the active metabolite of these drugs, vary among patients with lupus nephritis. The objective of this study was to examine whether concentration-controlled (CC) dosing (through therapeutic drug monitoring) of EC-MPS results in a higher proportion of participants achieving target exposure of MPA compared with fixed-dosing (FD). An additional aim of the study was to evaluate the influence of CC dosing on clinical outcomes. METHODS: Nineteen participants were randomly assigned either to the FD or CC group. All the participants were eligible to have free and total measurements of MPA over a period of 8-12 hours on 3 different occasions. Area under the concentration-time curve between 0 and 12 hours (AUC0-12) was calculated using noncompartmental methods. Dose of EC-MPS was titrated according to AUC0-12 in the CC group. RESULTS: Thirty-two AUC0-12 measurements were obtained from 9 FD and 9 CC participants. Large inter-patient variability was observed in both groups but was more pronounced in the FD group. There were no significant differences between FD and CC participants in any pharmacokinetic parameters across the study visits, except for total C0 (FD 2.0 ± 0.3 mg/L versus CC 1.1 ± 0.3; P = 0.01) and dose-normalized C0 (FD 2.9 ± 0.2 mg/L/g versus CC 2.1 ± 0.7 mg/L/g; P = 0.04) at the second visit and total AUC0-12 (FD 66.6 ± 6.0 mg·h/L versus CC 35.2 ± 11.4 mg·h/L; P = 0.03) at the third visit. At the first study visit, 33.3% of the FD and 11.1% of the CC participants achieved the target area under the concentration-time curve (P = 0.58). From the second visit, none of the FD participants, compared with all the CC participants, achieved target AUC0-12 (P = 0.01). More CC participants achieved remission compared with FD participants (absolute difference of -22.2, 95% confidence interval (Equation is included in full-text article.)0.19 to 0.55; P = 0.62). The mean free MPA AUC0-12 was significantly lower in those who had complete remission. CONCLUSIONS: CC participants reached target AUC0-12 quicker. Larger studies are required to test clinical efficacy.


Assuntos
Monitoramento de Medicamentos , Inibidores Enzimáticos/farmacocinética , Nefrite Lúpica/tratamento farmacológico , Ácido Micofenólico/farmacocinética , Adulto , Inibidores Enzimáticos/sangue , Inibidores Enzimáticos/uso terapêutico , Feminino , Humanos , Nefrite Lúpica/sangue , Nefrite Lúpica/metabolismo , Masculino , Pessoa de Meia-Idade , Ácido Micofenólico/sangue , Ácido Micofenólico/uso terapêutico
10.
Bioorg Chem ; 82: 129-138, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30312868

RESUMO

Pyrimidine-fused compounds are of great interest for the discovery of potent bioactive agents. This study describes the synthesis of novel pyranopyrimidines 3a-f and pyranotriazolopyrimidines 4a-d derivatives via the cyclocondensation reaction of α-functionalized iminoether 2, which was obtained from 2-amino-3-cyanopyrane 1, with a series of primary aromatic amines and hydrazides, respectively. Structures of all synthesized compounds were established on the basis of spectroscopic methods including 1H NMR, 13C NMR and ES-HRMS. They were finally tested for their anticoagulant and anti-tyrosinase activities. Significant results have been obtained and the structure-activity relationship (SAR) was discussed with the help of molecular docking analysis.


Assuntos
Anticoagulantes/farmacologia , Inibidores Enzimáticos/farmacologia , Monofenol Mono-Oxigenase/antagonistas & inibidores , Piranos/farmacologia , Pirimidinas/farmacologia , Triazóis/farmacologia , Agaricus/enzimologia , Anticoagulantes/sangue , Anticoagulantes/síntese química , Anticoagulantes/química , Sítios de Ligação , Inibidores Enzimáticos/sangue , Inibidores Enzimáticos/síntese química , Inibidores Enzimáticos/química , Humanos , Simulação de Acoplamento Molecular , Estrutura Molecular , Monofenol Mono-Oxigenase/química , Tempo de Tromboplastina Parcial , Piranos/sangue , Piranos/síntese química , Piranos/química , Pirimidinas/sangue , Pirimidinas/síntese química , Pirimidinas/química , Relação Estrutura-Atividade , Triazóis/sangue , Triazóis/síntese química , Triazóis/química
11.
Xenobiotica ; 49(11): 1338-1343, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30507339

RESUMO

1. S-EPA is a sulfur-substitution analog of epacadostat (EPA), an effective small molecule indoleamine 2,3-dioxgenase1 (IDO) inhibitor. By in vitro and in vivo experiments, pharmacokinetic differences of two closely related analogs, S-EPA and EPA was investigated in this study. 2. Liver microsomes clearance experiments showed S-EPA had comparable metabolic stability with EPA in rat and human liver microsomes. The whole blood distribution experiments showed the distribution ratio of S-EPA in blood cells to plasma in mice, rats, dogs and monkey was 1.2, 4.8, 2.2 and 40.6, respectively. While the distribution ratio of EPA ranged from 0.94 to 1.30 in mice, rats, dogs and was 3.1 in monkeys. 3. The pharmacokinetic study in rats showed the exposure (AUClast) of S-EPA in plasma and blood cells was 1.7-fold and 3.9-fold higher than that of EPA, respectively. Moreover, the exposure ratio of S-EPA in blood cells to plasma was 3.7, while the ratio of EPA was 1.6. 4. In CT26 tumor bearing mice, the IDO inhibition of S-EPA and EPA on plasma or tumor kynurenine was generally consistent. And the inhibition ratio could reach at more than 50% at 3 h after single dose, at least lasting up to 8 h.


Assuntos
Inibidores Enzimáticos/farmacocinética , Indolamina-Pirrol 2,3,-Dioxigenase/antagonistas & inibidores , Oximas/farmacocinética , Sulfetos/farmacocinética , Sulfonamidas/farmacocinética , Animais , Linhagem Celular Tumoral , Cães , Estabilidade de Medicamentos , Inibidores Enzimáticos/sangue , Inibidores Enzimáticos/química , Humanos , Cinurenina/sangue , Cinurenina/metabolismo , Macaca fascicularis , Camundongos Endogâmicos BALB C , Microssomos Hepáticos/efeitos dos fármacos , Microssomos Hepáticos/metabolismo , Transplante de Neoplasias , Oximas/sangue , Oximas/química , Ratos Sprague-Dawley , Sulfetos/sangue , Sulfetos/química , Sulfonamidas/sangue , Sulfonamidas/química
12.
AAPS PharmSciTech ; 20(5): 218, 2019 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-31187334

RESUMO

The aim of this study was to develop a self-microemulsifying drug delivery system (SMEDDS) for enhancement of the oral bioavailability of isoliquiritigenin (ISL) as well as evaluate its in vivo anti-hyperuricemic effect in rats. The ISL-loaded self-microemulsifying drug delivery system (ISL-SMEDDS) was comprised of ethyl oleate (EO, oil phase), Tween 80 (surfactant), and PEG 400 (co-surfactant). The ISL-SMEDDS exhibited an acceptable narrow size distribution (44.78 ± 0.35 nm), negative zeta potential (- 10.67 ± 0.86 mV), and high encapsulation efficiency (98.17 ± 0.24%). The in vitro release study indicated that the release rates of the formulation were obviously higher in different release media (HCl, pH 1.2; PBS, pH 6.8; double-distilled water, pH 7.0) compared with the ISL solution. The oral bioavailability of the ISL-SMEDDS was enhanced by 4.71 times in comparison with the free ISL solution. More importantly, ISL-SMEDDS significantly reduced uric acid level by inhibiting xanthine oxidase (XOD) activity in the model rats. Collectively, the prepared ISL-SMEDDS proved to be potential carriers for enhancing the solubility and oral bioavailability of ISL, as well as ameliorating its anti-hyperuricemic effect.


Assuntos
Chalconas/administração & dosagem , Chalconas/sangue , Sistemas de Liberação de Medicamentos/métodos , Hiperuricemia/sangue , Hiperuricemia/tratamento farmacológico , Administração Oral , Animais , Disponibilidade Biológica , Emulsões , Inibidores Enzimáticos/administração & dosagem , Inibidores Enzimáticos/sangue , Masculino , Polietilenoglicóis/administração & dosagem , Polietilenoglicóis/metabolismo , Ratos , Ratos Sprague-Dawley , Solubilidade , Tensoativos/administração & dosagem , Tensoativos/metabolismo
13.
Mod Rheumatol ; 29(6): 1002-1006, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30289014

RESUMO

Objectives: This study aimed to determine the association between the dosage and pharmacokinetics of mycophenolate mofetil (MMF) in juvenile patients with autoimmune diseases.Methods: Totally, 29 patients were administered oral MMF. The blood concentrations of mycophenolate acid (MPA) at seven points, the area under the time-concentration curve (MPA-AUC0-12h), the peak concentration (Cmax), and the time to peak concentration (Tmax) were measured. To obtain a dose-normalized MPA-AUC0-12h value, the actual measured MPA-AUC0-12h value was divided by the dose value of the morning administration corrected for body weight (BW) or body surface area (BSA). The patients were classified into three age groups (group 1, ≤10 years; group 2, >10-≤15 years; and group 3, >15 years), and pharmacokinetic parameters were compared among the groups.Results: In total, we obtained 37 measurements. The actual measured MPA-AUC0-12h values and the MPA-AUC0-12h values corrected for dose per BW and Tmax were lower in young patients. The MPA-AUC0-12h values corrected for dose per BSA and Cmax were comparable among all the groups.Conclusion: In patients with juvenile autoimmune diseases, determining MMF administration dosage according to BSA may facilitate MPA-AUC0-12h value prediction.


Assuntos
Doenças Autoimunes/tratamento farmacológico , Inibidores Enzimáticos/sangue , Imunossupressores/sangue , Ácido Micofenólico/sangue , Adolescente , Criança , Inibidores Enzimáticos/administração & dosagem , Inibidores Enzimáticos/uso terapêutico , Feminino , Humanos , Imunossupressores/administração & dosagem , Imunossupressores/uso terapêutico , Masculino , Ácido Micofenólico/administração & dosagem , Ácido Micofenólico/uso terapêutico , Adulto Jovem
14.
Bioorg Med Chem Lett ; 28(23-24): 3721-3725, 2018 12 15.
Artigo em Inglês | MEDLINE | ID: mdl-30348490

RESUMO

Endothelial lipase (EL) inhibitors have been shown to elevate HDL-C levels in pre-clinical murine models and have potential benefit in prevention and treatment of cardiovascular diseases. Modification of the 1-ethyl-3-hydroxy-1,5-dihydro-2H-pyrrol-2-one (DHP) lead, 1, led to the discovery of a series of potent tetrahydropyrimidinedione (THP) EL inhibitors. Synthesis and SAR studies including modification of the amide group, together with changes on the pyrimidinone core led to a series of arylcycloalkyl, indanyl, and tetralinyl substituted 5-amino or 5-hydroxypyrimidinedione-4-carboxamides. Several compounds were advanced to PK evaluation. Among them, compound 4a was one of the most potent with measurable ELHDL hSerum potency and compound 3g demonstrated the best overall pharmacokinetic parameters.


Assuntos
Inibidores Enzimáticos/química , Inibidores Enzimáticos/farmacologia , Lipase/antagonistas & inibidores , Pirimidinonas/química , Pirimidinonas/farmacologia , Animais , HDL-Colesterol/sangue , HDL-Colesterol/metabolismo , Inibidores Enzimáticos/sangue , Inibidores Enzimáticos/síntese química , Humanos , Lipase/sangue , Lipase/metabolismo , Camundongos , Modelos Moleculares , Pirimidinonas/sangue , Pirimidinonas/síntese química , Relação Estrutura-Atividade
15.
Ther Drug Monit ; 40(5): 572-580, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-29847459

RESUMO

BACKGROUND: The aim of this study was to characterize the pharmacokinetics of mycophenolic acid (MPA) and MPA glucuronide (MPAG) in Chinese renal transplant patients taking enteric-coated mycophenolate sodium (EC-MPS). Limited sampling strategies (LSSs) were developed to estimate the area under the concentration curve from 0 to 12 hours (AUC0-12h) of total and free MPA. Another objective was to investigate the correlation between high-performance liquid chromatography (HPLC) and enzyme-multiplied immunoassay technology (EMIT) for total MPA determination. METHODS: Serial blood samples were collected over 12 hours from 15 patients who were administered multiple doses of EC-MPS. LSS was developed by multiple stepwise regression analysis. Measurement by HPLC and EMIT was compared using Passing-Bablok regression and Bland-Altman analysis. RESULTS: Normalized to 720 mg twice daily, the AUC0-12h of total MPA and MPAG was 43.0 ± 17.4 and 653 ± 329 mg·h/L, respectively, whereas the free MPA AUC0-12h was 1.368 ± 0.988 mg·h/L. The free fraction of MPA was 3.01% ± 3.15%. The combination of C2h-C4h-C6h and C2h-C4h-C6h-C8h was found to be superior to estimate total and free MPA simultaneously. The EMIT showed an acceptable correlation with HPLC, with an AUC0-12h overestimation of 11.32% ± 15.77%. CONCLUSIONS: The pharmacokinetic profile of total and free MPA and its main metabolite MPAG was examined in Chinese adult renal transplant patients receiving EC-MPS. The use of LSS to estimate individual free and total MPA exposure could be useful in optimizing patient care.


Assuntos
Glucuronídeos/farmacocinética , Transplante de Rim , Ácido Micofenólico/análogos & derivados , Ácido Micofenólico/farmacocinética , Adolescente , Adulto , Área Sob a Curva , Povo Asiático , Cromatografia Líquida de Alta Pressão , Inibidores Enzimáticos/sangue , Inibidores Enzimáticos/farmacocinética , Técnica de Imunoensaio Enzimático de Multiplicação , Feminino , Glucuronídeos/sangue , Humanos , Masculino , Pessoa de Meia-Idade , Ácido Micofenólico/sangue , Comprimidos com Revestimento Entérico/farmacocinética , Adulto Jovem
16.
Eur J Mass Spectrom (Chichester) ; 24(4): 344-351, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-29629565

RESUMO

Foretinib (GSK1363089) is a multiple receptor tyrosine kinases inhibitor. In this study, a reliable, fast liquid chromatography-tandem mass spectrometric method was described for assaying foretinib in plasma, urine, and rat liver microsome samples. Simple extraction procedure by protein preciptation with acetonitrile was implemented for foretinib and brigatinib (internal standard) analysis. Chromatographic resolution of analytes was achieved on C18 column with the help of isocratic mobile phase. The binary mobile phase consisted of 60% ammonium formate (10 mM, pH 4.2) and 40% acetonitrile at a flow rate of 0.25 mL/min. Run time was 3 min, and both foretinib and brigatinib were eluted within 0.74 and 1.95 min; they were detected in positive ion mode utilizing multiple reactions monitoring mode. Linearity of the proposed method ranged from 5 to 500 ng/mL (r2 ≥ 0.9993) in the human plasma. Lower limit of quantification and detection were 6.0 and 1.8 ng/mL, respectively. Intraday and interday precision and accuracy were 0.16 to 1.67 % and -2.39 to -0.52 %. In vitro half-life and intrinsic clearance were 24.93 min and 6.56 mL/min/kg, respectively. Literature review showed that no previous studies have been proposed for the analytical quantification of foretinib in human plasma or its metabolic stability. The established method was also applied to estimate the rate of foretinib excretion in rat urine. The developed method can be used for foretinib pharmacokinetic applications.


Assuntos
Anilidas/sangue , Cromatografia Líquida/métodos , Quinolinas/sangue , Espectrometria de Massas em Tandem/métodos , Anilidas/urina , Animais , Inibidores Enzimáticos/sangue , Inibidores Enzimáticos/urina , Humanos , Limite de Detecção , Microssomos Hepáticos/química , Quinolinas/urina , Ratos
17.
Biomed Chromatogr ; 32(4)2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29193233

RESUMO

A specific, sensitive and stable high-performance liquid chromatographic-tandem mass spectrometry (LC-MS/MS) method was developed and validated for the quantitative determination of methyl 3-amino-6-methoxythieno [2,3-b]quinoline-2-carboxylate (PU-48), a novel diuretic thienoquinolin urea transporter inhibitor in rat plasma. In this method, the chromatographic separation of PU-48 was achieved with a reversed-phase C18 column (100 × 2.1 mm, 3 µm) at 35°C. The mobile phase consisted of acetonitrile and water with 0.05% formic acid added with a gradient elution at flow rate of 0.3 mL/min. Samples were detected with the triple-quadrupole tandem mass spectrometer with multiple reaction monitoring mode via electrospray ionization source in positive mode. The retention time were 6.2 min for PU-48 and 7.2 min for megestrol acetate (internal standard, IS). The monitored ion transitions were mass-to-charge ratio (m/z) 289.1 → 229.2 for PU-48 and m/z 385.3 → 267.1 for the internal standard. The calibration curve for PU-48 was linear over the concentration range of 0.1-1000 ng/mL (r2 > 0.99), and the lower limit of quantitation was 0.1 ng/mL. The precision, accuracy and stability of the method were validated adequately. The developed and validated method was successfully applied to the pharmacokinetic study of PU-48 in rats.


Assuntos
Proteínas de Transporte/antagonistas & inibidores , Cromatografia Líquida/métodos , Inibidores Enzimáticos/sangue , Proteínas de Membrana Transportadoras/metabolismo , Quinolinas/metabolismo , Espectrometria de Massas em Tandem/métodos , Animais , Estabilidade de Medicamentos , Inibidores Enzimáticos/química , Inibidores Enzimáticos/farmacocinética , Modelos Lineares , Masculino , Quinolinas/análise , Quinolinas/sangue , Ratos , Ratos Sprague-Dawley , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Transportadores de Ureia
18.
Chem Pharm Bull (Tokyo) ; 66(12): 1131-1152, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30504630

RESUMO

A novel series of 2-acyl-3-carboxyl-tetrahydroisoquinoline derivatives were synthesized and biologically evaluated. Among them, (S)-2-{(E)-3-furan-2-ylacryloyl}-7-[(2E,4E)-5-(2,4,6-trifluorophenyl)penta-2,4-dienyloxy]-1,2,3,4-tetrahydroisoquinoline-3-carboxylic acid (compound 17u) was identified as a potent protein tyrosine phosphatase 1B (PTP1B) inhibitor without peroxisome proliferator-activated receptor (PPAR) γ activation: PTP1B inhibition IC50=0.19 µM and PPARγ ΕC50>10 µM. Compound 17u exhibited mixed-type inhibition for PTP1B, and this mode of inhibition was rationalized by computational ligand docking into the catalytic and allosteric sites of PTP1B. Compound 17u also showed high oral absorption at 10 mg/kg (per os (p.o.), Cmax=4.67 µM) in rats, significantly reduced non-fasting plasma glucose and triglyceride levels with no side effects at 30 mg/kg/d (p.o.) for 4 weeks, and attenuated elevations in plasma glucose levels in the oral glucose tolerance test performed 24 h after its final administration in db/db mice. In conclusion, the substituted 2-acyl-3-carboxyl-tetrahydroisoquinoline is a novel scaffold of mixed-type PTP1B inhibitors without PPARγ activation, and compound 17u has potential as an efficacious and safe anti-diabetic drug as well as a useful tool for investigations on the physiological and pathophysiological effects of mixed-type PTP1B inhibition.


Assuntos
Inibidores Enzimáticos/farmacologia , Hipoglicemiantes/farmacologia , Proteína Tirosina Fosfatase não Receptora Tipo 1/antagonistas & inibidores , Tetra-Hidroisoquinolinas/farmacologia , Animais , Diabetes Mellitus Experimental/tratamento farmacológico , Relação Dose-Resposta a Droga , Inibidores Enzimáticos/sangue , Inibidores Enzimáticos/química , Humanos , Hipoglicemiantes/sangue , Hipoglicemiantes/química , Masculino , Camundongos , Camundongos Endogâmicos , Simulação de Acoplamento Molecular , Estrutura Molecular , PPAR gama/metabolismo , Proteína Tirosina Fosfatase não Receptora Tipo 1/metabolismo , Ratos , Ratos Sprague-Dawley , Relação Estrutura-Atividade , Tetra-Hidroisoquinolinas/sangue , Tetra-Hidroisoquinolinas/química
19.
J Microencapsul ; 35(4): 313-326, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29683357

RESUMO

Rhein (RH) has many bioactivities, but the application was limited of its poor solubility. The present study aimed to establish an efficient method for the synthesis of rhein amide derivatives (RAD) to increase the solubility and anti-tumour activity. RAD exhibited stronger anti-tumour activity than RH in MTT assay. The solubility and oil/water partition coefficient results indicated that rhein-phenylalanine and rhein-isoleucine have better absorption effect, which was consolidated in pharmacokinetic study. Then, rhein-phenylalanine and rhein-isoleucine were prepared into nanocrystals via the precipitation high-pressure homogenisation method. Additionally, the nanocrystals both displayed much higher dissolution profiles than the bulk drugs. Pharmacokinetics study indicated that the AUC0-∞ and Cmax of nanocrystals increased markedly (p < 0.01). However, the concentration of RH-Phe-NC was far less than RH-Ile-NC in plasma. Consequently, RH-Ile-NC was validated to be an applicable way to improve the bioavailability of RH, which owns a promising future in clinical application.


Assuntos
Antraquinonas/sangue , Antraquinonas/química , Inibidores Enzimáticos/sangue , Inibidores Enzimáticos/química , Nanopartículas/química , Amidas/sangue , Amidas/síntese química , Amidas/química , Animais , Antraquinonas/síntese química , Disponibilidade Biológica , Inibidores Enzimáticos/síntese química , Células Hep G2 , Humanos , Isoleucina/análogos & derivados , Isoleucina/sangue , Isoleucina/síntese química , Masculino , Fenilalanina/análogos & derivados , Fenilalanina/sangue , Fenilalanina/síntese química , Ratos Sprague-Dawley , Solubilidade
20.
Artigo em Inglês | MEDLINE | ID: mdl-28739782

RESUMO

Coadministering pyrazinamide (PZA) with the xanthine oxidase inhibitor allopurinol increases systemic levels of the active metabolite, pyrazinoic acid (POA), but the effects on bactericidal activity against tuberculosis are unknown. We randomized healthy volunteers to take a single dose of PZA (either 10 or 25 mg/kg of body weight) at the first visit and the same dose 7 days later, coadministered with allopurinol (100 mg daily; 2 days before to 1 day after the PZA dose). Blood was drawn at intervals until 48 h after each PZA dose, and drug levels were measured using liquid chromatography-tandem mass spectrometry. Whole-blood bactericidal activity (WBA) was measured by inoculating blood samples with Mycobacterium tuberculosis and estimating the change in bacterial CFU after 72 h of incubation. Allopurinol increased the POA area under the concentration-time curve from 0 to 8 h (AUC0-8) (18.32 h · µg/ml versus 24.63 h · µg/ml for PZA alone versus PZA plus allopurinol) (P < 0.001) and its peak plasma concentration (Cmax) (2.81 µg/ml versus 4.00 µg/ml) (P < 0.001). There was no effect of allopurinol on mean cumulative WBA (0.01 ± 0.02 ΔlogCFU versus 0.00 ± 0.02 ΔlogCFU for PZA alone versus PZA plus allopurinol) (P = 0.49). Higher systemic POA levels were associated with greater WBA levels (P < 0.001), but the relationship was evident only at low POA concentrations. The lack of an effect of allopurinol on WBA despite a significant increase in blood POA levels suggests that host-generated POA may be less effective than POA generated inside bacteria. Coadministration of allopurinol does not appear to be a useful strategy for increasing the efficacy of PZA in clinical practice. (This study has been registered at ClinicalTrials.gov under registration no. NCT02700347.).


Assuntos
Alopurinol/sangue , Antituberculosos/sangue , Atividade Bactericida do Sangue/efeitos dos fármacos , Inibidores Enzimáticos/sangue , Mycobacterium tuberculosis/efeitos dos fármacos , Pirazinamida/sangue , Adulto , Idoso , Alopurinol/farmacologia , Antituberculosos/farmacologia , Quimioterapia Combinada , Inibidores Enzimáticos/farmacologia , Voluntários Saudáveis , Humanos , Testes de Sensibilidade Microbiana , Pessoa de Meia-Idade , Pirazinamida/farmacologia , Xantina Oxidase/antagonistas & inibidores , Adulto Jovem
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