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1.
Artigo em Inglês | MEDLINE | ID: mdl-32068354

RESUMO

BMS-986184 is a human, second-generation, anti-interferon-γ-induced protein 10 (IP-10) monoclonal antibody. In this study the pharmacokinetics and target engagement (TE) of BMS-986184 in healthy participants were characterized using population-based target-mediated drug disposition (TMDD) modeling and data from a first-in-human study (NCT02864264). The results of the first-in-human study and the model generated were used to conduct stochastic simulations of a virtual population of healthy participants to predict pharmacokinetic exposures and TE responses for different dosage regimens. A 2-compartment, 2-target, TMDD structural model, assuming quasi-steady-state and stimulated production on treatment, was developed by simultaneous fitting of the total drug, serum-free IP-10, and serum total IP-10 concentration data, with the second unobservable target contribution to drug elimination described by the Michaelis-Menten elimination term. Model evaluation confirmed agreement between model predictions and observed data. Simulation of a virtual population of healthy individuals demonstrated that steady state was reached at the eighth dosing interval, and that around 150 mg subcutaneously every other week could be a suitable target dosage regimen for future clinical trials. Integrated modeling strategies such as this can be used to help guide rational clinical trial development of drugs with TMDD, leading to improved dose selection and greater patient benefits.

2.
J Med Chem ; 62(20): 8973-8995, 2019 Oct 24.
Artigo em Inglês | MEDLINE | ID: mdl-31318208

RESUMO

Small molecule JAK inhibitors have emerged as a major therapeutic advancement in treating autoimmune diseases. The discovery of isoform selective JAK inhibitors that traditionally target the catalytically active site of this kinase family has been a formidable challenge. Our strategy to achieve high selectivity for TYK2 relies on targeting the TYK2 pseudokinase (JH2) domain. Herein we report the late stage optimization efforts including a structure-guided design and water displacement strategy that led to the discovery of BMS-986165 (11) as a high affinity JH2 ligand and potent allosteric inhibitor of TYK2. In addition to unprecedented JAK isoform and kinome selectivity, 11 shows excellent pharmacokinetic properties with minimal profiling liabilities and is efficacious in several murine models of autoimmune disease. On the basis of these findings, 11 appears differentiated from all other reported JAK inhibitors and has been advanced as the first pseudokinase-directed therapeutic in clinical development as an oral treatment for autoimmune diseases.

3.
J Med Chem ; 62(20): 8953-8972, 2019 Oct 24.
Artigo em Inglês | MEDLINE | ID: mdl-31314518

RESUMO

As a member of the Janus (JAK) family of nonreceptor tyrosine kinases, TYK2 plays an important role in mediating the signaling of pro-inflammatory cytokines including IL-12, IL-23, and type 1 interferons. The nicotinamide 4, identified by a SPA-based high-throughput screen targeting the TYK2 pseudokinase domain, potently inhibits IL-23 and IFNα signaling in cellular assays. The described work details the optimization of this poorly selective hit (4) to potent and selective molecules such as 47 and 48. The discoveries described herein were critical to the eventual identification of the clinical TYK2 JH2 inhibitor (see following report in this issue). Compound 48 provided robust inhibition in a mouse IL-12-induced IFNγ pharmacodynamic model as well as efficacy in an IL-23 and IL-12-dependent mouse colitis model. These results demonstrate the ability of TYK2 JH2 domain binders to provide a highly selective alternative to conventional TYK2 orthosteric inhibitors.

4.
ACS Med Chem Lett ; 10(3): 383-388, 2019 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-30891145

RESUMO

In sharp contrast to a previously reported series of 6-anilino imidazopyridazine based Tyk2 JH2 ligands, 6-((2-oxo-N1-substituted-1,2-dihydropyridin-3-yl)amino)imidazo[1,2-b]pyridazine analogs were found to display dramatically improved metabolic stability. The N1-substituent on 2-oxo-1,2-dihydropyridine ring can be a variety of alkyl, aryl, and heteroaryl groups, but among them, 2-pyridyl provided much enhanced Caco-2 permeability, attributed to its ability to form intramolecular hydrogen bonds. Further structure-activity relationship studies at the C3 position led to the identification of highly potent and selective Tyk2 JH2 inhibitor 6, which proved to be highly effective in inhibiting IFNγ production in a rat pharmacodynamics model and fully efficacious in a rat adjuvant arthritis model.

5.
J Med Chem ; 62(5): 2265-2285, 2019 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-30785748

RESUMO

Recently, our research group reported the identification of BMS-986104 (2) as a differentiated S1P1 receptor modulator. In comparison to fingolimod (1), a full agonist of S1P1 currently marketed for the treatment of relapse remitting multiple sclerosis (RRMS), 2 offers several potential advantages having demonstrated improved safety multiples in preclinical evaluations against undesired pulmonary and cardiovascular effects. In clinical trials, 2 was found to exhibit a pharmacokinetic half-life ( T1/2) longer than that of 1, as well as a reduced formation of the phosphate metabolite that is required for activity against S1P1. Herein, we describe our efforts to discover highly potent, partial agonists of S1P1 with a shorter T1/2 and increased in vivo phosphate metabolite formation. These efforts culminated in the discovery of BMS-986166 (14a), which was advanced to human clinical evaluation. The pharmacokinetic/pharmacodynamic (PK/PD) relationship as well as pulmonary and cardiovascular safety assessments are discussed. Furthermore, efficacy of 14a in multiple preclinical models of autoimmune diseases are presented.

6.
Clin Cancer Res ; 24(20): 5178-5189, 2018 10 15.
Artigo em Inglês | MEDLINE | ID: mdl-30021910

RESUMO

Purpose: The ganglioside fucosyl-GM1 (FucGM1) is a tumor-associated antigen expressed in a large percentage of human small cell lung cancer (SCLC) tumors, but absent in most normal adult tissues, making it a promising target in immuno-oncology. This study was undertaken to evaluate the preclinical efficacy of BMS-986012, a novel, nonfucosylated, fully human IgG1 antibody that binds specifically to FucGM1.Experimental Design: The antitumor activity of BMS-986012 was evaluated in in vitro assays using SCLC cells and in mouse xenograft and syngeneic tumor models, with and without chemotherapeutic agents and checkpoint inhibitors.Results: BMS-986012 showed a high binding affinity for FcγRIIIa (CD16), which resulted in enhanced antibody-dependent cellular cytotoxicity (ADCC) against FucGM1-expressing tumor cell lines. BMS-986012-mediated tumor cell killing was also observed in complement-dependent cytotoxicity (CDC) and antibody-dependent cellular phagocytosis (ADCP) assays. In several mouse SCLC models, BMS-986012 demonstrated efficacy and was well tolerated. In the DMS79 xenograft model, tumor regression was achieved with BMS-986012 doses of 0.3 mg/kg and greater; antitumor activity was enhanced when BMS-986012 was combined with standard-of-care cisplatin or etoposide. In a syngeneic model, tumors derived from a genetically engineered model of SCLC were treated with BMS-986012 or anti-FucGM1 with a mouse IgG2a Fc and their responses evaluated; when BMS-986012 was combined with anti-PD-1 or anti-CD137 antibody, therapeutic responses significantly improved.Conclusions: Single-agent BMS-986012 demonstrated robust antitumor activity, with the addition of chemotherapeutic or immunomodulatory agents further inhibiting SCLC growth in the same models. These preclinical data supported evaluation of BMS-986012 in a phase I clinical trial of patients with relapsed, refractory SCLC. Clin Cancer Res; 24(20); 5178-89. ©2018 AACR.


Assuntos
Antineoplásicos Imunológicos/farmacologia , Gangliosídeo G(M1)/análogos & derivados , Animais , Citotoxicidade Celular Dependente de Anticorpos/imunologia , Antígenos de Neoplasias/imunologia , Carcinoma de Células Pequenas/tratamento farmacológico , Carcinoma de Células Pequenas/metabolismo , Carcinoma de Células Pequenas/patologia , Linhagem Celular Tumoral , Modelos Animais de Doenças , Relação Dose-Resposta a Droga , Avaliação Pré-Clínica de Medicamentos , Gangliosídeo G(M1)/antagonistas & inibidores , Gangliosídeo G(M1)/imunologia , Gangliosídeo G(M1)/metabolismo , Humanos , Imuno-Histoquímica , Imunomodulação/efeitos dos fármacos , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/patologia , Camundongos , Ligação Proteica , Receptores de IgG/metabolismo , Membro 9 da Superfamília de Receptores de Fatores de Necrose Tumoral/antagonistas & inibidores , Ensaios Antitumorais Modelo de Xenoenxerto
7.
J Trauma Acute Care Surg ; 85(3): 580-587, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-29847538

RESUMO

BACKGROUND: To investigate the effect of biliary tract external drainage (BTED) on inflammatory mediators and pathomorphism of intestine, liver, and lung in septic rats. METHOD: 48 SD rats (n = 8 per group) were randomized into six groups: control, sepsis, sepsis plus BTED, normal bile (obtained from eight healthy rats), and septic bile infusion for 6 hours respectively to test the effects of BTED bile infusion on cytokines' expression and tissue injury in the intestine, liver, and lung of septic/normal rats. Co-cultivation of intestinal epithelial cells (IEC-6) with bile for 12 hours was performed to evaluate the potential cytotoxicity of septic bile. Survival rate for sepsis plus BTED rats was detected compared with sepsis without BTED group (n = 20 per group) at 24, 48, and 72 hours, respectively. RESULTS: BTED for 6 hours significantly reduced the mRNA expression levels of tumor necrosis factor alpha (TNF-α) and IL-1ß (all p < 0.05 vs. sepsis group), whereas mRNA expression of TNF-α and IL-1ß in the intestine was increased after 6 hours' septic bile infusion compared with normal bile infusion group (all p < 0.05). TNF-α concentration in septic bile was significantly higher than that in the control group (p < 0.001). Tissue injury was significantly attenuated after 6 hours' BTED. CONCLUSIONS: BTED can significantly restrain the mRNA expression of TNF-α and IL-1ß in the intestine, liver, and lung and attenuate histological damage in septic rats.


Assuntos
Bile/metabolismo , Procedimentos Cirúrgicos do Sistema Biliar/métodos , Drenagem/métodos , Mediadores da Inflamação/metabolismo , Fígado/metabolismo , Pulmão/metabolismo , Sepse/metabolismo , Animais , Bile/fisiologia , Citocinas/metabolismo , Modelos Animais de Doenças , Interleucina-1beta/genética , Intestinos/fisiopatologia , Intestinos/cirurgia , Fígado/fisiopatologia , Pulmão/fisiopatologia , Masculino , Insuficiência de Múltiplos Órgãos/genética , Insuficiência de Múltiplos Órgãos/patologia , RNA Mensageiro/genética , Ratos , Ratos Sprague-Dawley/genética , Sepse/patologia , Sepse/cirurgia , Fator de Necrose Tumoral alfa/genética
8.
Bioorg Med Chem Lett ; 28(2): 85-93, 2018 01 15.
Artigo em Inglês | MEDLINE | ID: mdl-29233651

RESUMO

We disclose the optimization of a high throughput screening hit to yield benzothiazine and tetrahydroquinoline sulfonamides as potent RORγt inverse agonists. However, a majority of these compounds showed potent activity against pregnane X receptor (PXR) and modest activity against liver X receptor α (LXRα). Structure-based drug design (SBDD) led to the identification of benzothiazine and tetrahydroquinoline sulfonamide analogs which completely dialed out LXRα activity and were less potent at PXR. Pharmacodynamic (PD) data for compound 35 in an IL-23 induced IL-17 mouse model is discussed along with the implications of a high Ymax in the PXR assay for long term preclinical pharmacokinetic (PK) studies.


Assuntos
Compostos Bicíclicos com Pontes/farmacologia , Desenho de Drogas , Propanóis/farmacologia , Receptores do Ácido Retinoico/agonistas , Receptores de Esteroides/agonistas , Sulfonamidas/farmacologia , Animais , Compostos Bicíclicos com Pontes/síntese química , Compostos Bicíclicos com Pontes/química , Cristalografia por Raios X , Relação Dose-Resposta a Droga , Humanos , Receptores X do Fígado/agonistas , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Modelos Moleculares , Estrutura Molecular , Receptor de Pregnano X , Propanóis/síntese química , Propanóis/química , Relação Estrutura-Atividade , Sulfonamidas/síntese química , Sulfonamidas/química
9.
Bioanalysis ; 9(20): 1573-1588, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-29072496

RESUMO

AIM: IP-10 is a protein target for the treatment of Crohn's disease. Inhibition of IP-10 by anti-IP-10 mAbs neutralizes its various biological activities. The measurement of free IP-10 suppression as a target engagement biomarker is required for the assessment of drug effect on the target. RESULTS: The development of highly sensitive immunoaffinity-LC-MS/MS assays for quantifying free and total IP-10 in cynomolgus monkey serum is reported for the first time. This paper details strategies for maximizing assay sensitivity by selecting digestion routes, and optimizing immunocapture to achieve full recovery and minimal matrix effect. For the free IP-10 assay, bioanalytical strategies have been established to minimize drug/ligand dissociation. CONCLUSION: The assays have been implemented for target engagement measurement, pharmacokinetic-pharmacodynamic correlation, and human dose projections.


Assuntos
Biomarcadores/sangue , Quimiocina CXCL10/sangue , Cromatografia de Afinidade , Espectrometria de Massas em Tandem , Sequência de Aminoácidos , Animais , Anticorpos Monoclonais/imunologia , Quimiocina CXCL10/genética , Quimiocina CXCL10/imunologia , Cromatografia Líquida de Alta Pressão , Humanos , Ligantes , Macaca fascicularis , Peptídeos/química , Peptídeos/isolamento & purificação , Proteínas Recombinantes/biossíntese , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Alinhamento de Sequência
10.
J Leukoc Biol ; 102(5): 1271-1280, 2017 11.
Artigo em Inglês | MEDLINE | ID: mdl-28899907

RESUMO

IFN-γ-inducible protein 10 (CXCL10), a chemokine that is abundantly secreted in response to inflammatory stimuli, has been implicated in the pathogenesis of multiple inflammatory diseases, such as inflammatory bowel disease. Whereas CXCL10 is traditionally recognized for recruiting pathogenic T cells to inflamed sites, its nonchemotactic role during inflammation remains poorly defined. In this report, we identified a novel function of CXCL10 in the regulation of the inflammatory potential of human monocytes to produce cytokines. We found that CXCL10 was necessary and sufficient for IFN-γ-primed human monocytes to induce a robust production of proinflammatory cytokines, such as IL-12 and IL-23. CXCL10-induced monocyte production of these cytokines depended on CXCR3 receptor engagement as well as on the Iκ B kinase and p38 MAPK signaling pathways. By using an innate-mediated murine colitis model, we demonstrated that anti-CXCL10 Ab treatment robustly suppressed the local production of myeloid-derived inflammatory cytokines and intestinal tissue damage. Together, our data unravel a previously unappreciated role of CXCL10 in the amplification of myeloid cell-mediated inflammatory responses. Targeting CXCL10 is therefore an attractive approach to treating inflammatory diseases that are driven by innate and adaptive immunity.


Assuntos
Imunidade Adaptativa , Quimiocina CXCL10/imunologia , Colite Ulcerativa/imunologia , Doença de Crohn/imunologia , Imunidade Inata , Monócitos/imunologia , Animais , Anticorpos Neutralizantes/administração & dosagem , Antígenos CD40/antagonistas & inibidores , Quimiocina CXCL10/antagonistas & inibidores , Quimiocina CXCL10/genética , Colite/induzido quimicamente , Colite/genética , Colite/imunologia , Colite/patologia , Colite Ulcerativa/genética , Colite Ulcerativa/patologia , Doença de Crohn/genética , Doença de Crohn/patologia , Feminino , Regulação da Expressão Gênica , Humanos , Quinase I-kappa B/genética , Quinase I-kappa B/imunologia , Interferon gama/genética , Interferon gama/imunologia , Interleucina-12/genética , Interleucina-12/imunologia , Interleucina-23/genética , Interleucina-23/imunologia , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Monócitos/citologia , Cultura Primária de Células , Receptores CXCR3/genética , Receptores CXCR3/imunologia , Transdução de Sinais , Proteínas Quinases p38 Ativadas por Mitógeno/genética , Proteínas Quinases p38 Ativadas por Mitógeno/imunologia
11.
Biomed Pharmacother ; 91: 476-484, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28478272

RESUMO

Hypoxia inducible factor-1α (HIF-1α) plays an essential role in hypoxia and inflammatory response. Oxygen metabolic dysfunction and cascade amplification of inflammatory response are prominent pathophysiological characteristics in sepsis induced acute lung injury (ALI). In this study, we started with septic mesenteric lymph injection model to investigate whether HIF-1α played a role in the pathogenesis of ALI induced by septic lymph. The data demonstrated that rats injected with septic lymph showed a significant higher Lung Injury Scale and MPO(myeloperoxidase) levels than that of rats injected with normal saline/lymph. ALI was associated with a higher degree of HIF-1α expression in the lungs infused by septic lymph. Intratracheal delivery of YC-1(3-(5'-hydroxymethyl-2'-furyl)-1-benzylindazole) significantly attenuated lung inflammatory damages. Furthermore, in vitro studies, human alveolar type II epithelial cell (A549)/human pulmonary microvascular endothelial cell (HPMEC) incubated by septic lymph showed dramatically decreased cell viability, higher levels of inflammatory cytokines (TNF-α, IL-6 and IL-1ß) and excitation of HIF-1α expression (Immunofluorescence localization/RT-PCR test) simultaneously. Nevertheless, compared with the non-silencing cell lines, A549/HPMEC with HIF-1α gene silencing manifested increased viability and restrained cytokines' expression after incubation with septic lymph. These results indicate that HIF-1α expression can be induced and activated in rats during the acute lung inflammatory damages triggered by septic lymph injection and that lung inflammatory injuries occur via a HIF-1α-dependent pathway.


Assuntos
Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Lesão Pulmonar/metabolismo , Pulmão/patologia , Linfa/metabolismo , Pneumonia/metabolismo , Sepse/metabolismo , Células A549 , Animais , Sobrevivência Celular , Citocinas/metabolismo , Células Endoteliais/metabolismo , Inativação Gênica , Humanos , Indazóis/farmacologia , Indazóis/uso terapêutico , Lesão Pulmonar/tratamento farmacológico , Masculino , Artérias Mesentéricas , Peroxidase/metabolismo , Ratos Sprague-Dawley , Sepse/tratamento farmacológico
12.
Medchemcomm ; 8(4): 725-729, 2017 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-30108791

RESUMO

Recently, our research group reported the identification of prodrug amino-alcohol 2 as a potent and efficacious S1P1 receptor modulator. This molecule is differentiated preclinically over the marketed drug fingolimod (Gilenya 1), whose active phosphate metabolite is an S1P1 full agonist, in terms of pulmonary and cardiovascular safety. S1P1 partial agonist 2, however, has a long half-life in rodents and was projected to have a long half-life in humans. The purpose of this communication is to disclose highly potent partial agonists of S1P1 with shorter half-lives relative to the clinical compound 2. PK/PD relationships as well as their preclinical pulmonary and cardiovascular safety assessment are discussed.

13.
Anal Chim Acta ; 945: 57-66, 2016 Nov 16.
Artigo em Inglês | MEDLINE | ID: mdl-27968716

RESUMO

LC-MS/MS has been widely applied to the quantitative analysis of tissue samples. However, one key remaining issue is that the extraction recovery of analyte from spiked tissue calibration standard and quality control samples (QCs) may not accurately represent the "true" recovery of analyte from incurred tissue samples. This may affect the accuracy of LC-MS/MS tissue bioanalysis. Here, we investigated whether the recovery determined using tissue QCs by LC-MS/MS can accurately represent the "true" recovery from incurred tissue samples using two model compounds: BMS-986104, a S1P1 receptor modulator drug candidate, and its phosphate metabolite, BMS-986104-P. We first developed a novel acid and surfactant assisted protein precipitation method for the extraction of BMS-986104 and BMS-986104-P from rat tissues, and determined their recoveries using tissue QCs by LC-MS/MS. We then used radioactive incurred samples from rats dosed with 3H-labeled BMS-986104 to determine the absolute total radioactivity recovery in six different tissues. The recoveries determined using tissue QCs and incurred samples matched with each other very well. The results demonstrated that, in this assay, tissue QCs accurately represented the incurred tissue samples to determine the "true" recovery, and LC-MS/MS assay was accurate for tissue bioanalysis. Another aspect we investigated is how the tissue QCs should be prepared to better represent the incurred tissue samples. We compared two different QC preparation methods (analyte spiked in tissue homogenates or in intact tissues) and demonstrated that the two methods had no significant difference when a good sample preparation was in place. The developed assay showed excellent accuracy and precision, and was successfully applied to the quantitative determination of BMS-986104 and BMS-986104-P in tissues in a rat toxicology study.


Assuntos
Modelos Químicos , Animais , Cromatografia Líquida , Ratos , Padrões de Referência , Espectrometria de Massas em Tandem
14.
Bioanalysis ; 8(13): 1383-401, 2016 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-27277879

RESUMO

BACKGROUND: Antibody-drug conjugates (ADCs) are complex drug constructs with multiple species in the heterogeneous mixture that contribute to their efficacy and toxicity. The bioanalysis of ADCs involves multiple assays and analytical platforms. METHODS: A series of ligand binding and LC-MS/MS (LB-LC-MS/MS) hybrid assays, through different combinations of anti-idiotype (anti-Id), anti-payload, or generic capture reagents, and cathepsin-B or trypsin enzyme digestion, were developed and evaluated for the analysis of conjugated-payload as well as for species traditionally measured by ligand-binding assays, total-antibody and conjugated-antibody. RESULTS & CONCLUSION: Hybrid assays are complementary or viable alternatives to ligand-binding assay for ADC bioanalysis and PK/PD modeling. The fit-for-purpose choice of analytes, assays and platforms and an integrated strategy from Discovery to Development for ADC PK and bioanalysis are recommended.


Assuntos
Imunoconjugados/sangue , Preparações Farmacêuticas/sangue , Espectrometria de Massas em Tandem/métodos , Animais , Cromatografia Líquida/métodos , Haplorrinos , Humanos , Imunoensaio/métodos , Imunoconjugados/análise , Limite de Detecção , Preparações Farmacêuticas/análise , Ratos
15.
Drug Metab Dispos ; 44(7): 1123-38, 2016 07.
Artigo em Inglês | MEDLINE | ID: mdl-27098743

RESUMO

We used the intestinal segregated flow model (SFM) versus the traditional model (TM), nested within physiologically based pharmacokinetic (PBPK) models, to describe the biliary and urinary excretion of morphine 3ß-glucuronide (MG) after intravenous and intraduodenal dosing of morphine in rats in vivo. The SFM model describes a partial (5%-30%) intestinal blood flow perfusing the transporter- and enzyme-rich enterocyte region, whereas the TM describes 100% flow perfusing the intestine as a whole. For the SFM, drugs entering from the circulation are expected to be metabolized to lesser extents by the intestine due to the segregated flow, reflecting the phenomenon of shunting and route-dependent intestinal metabolism. The poor permeability of MG crossing the liver or intestinal basolateral membranes mandates that most of MG that is excreted into bile is hepatically formed, whereas MG that is excreted into urine originates from both intestine and liver metabolism, since MG is effluxed back to blood. The ratio of MG amounts in urine/bile [Formula: see text] for intraduodenal/intravenous dosing is expected to exceed unity for the SFM but approximates unity for the TM. Compartmental analysis of morphine and MG data, without consideration of the permeability of MG and where MG is formed, suggests the ratio to be 1 and failed to describe the kinetics of MG. The observed intraduodenal/intravenous ratio of [Formula: see text] (2.55 at 4 hours) was better predicted by the SFM-PBPK (2.59 at 4 hours) and not the TM-PBPK (1.0), supporting the view that the SFM is superior for the description of intestinal-liver metabolism of morphine to MG. The SFM-PBPK model predicts an appreciable contribution of the intestine to first pass M metabolism.


Assuntos
Duodeno/irrigação sanguínea , Duodeno/metabolismo , Circulação Hepática , Fígado/irrigação sanguínea , Fígado/metabolismo , Modelos Biológicos , Derivados da Morfina/farmacocinética , Morfina/farmacocinética , Circulação Esplâncnica , Administração Intravenosa , Administração Oral , Animais , Permeabilidade da Membrana Celular , Eliminação Hepatobiliar , Inativação Metabólica , Masculino , Morfina/administração & dosagem , Morfina/sangue , Morfina/urina , Derivados da Morfina/sangue , Derivados da Morfina/urina , Ratos Sprague-Dawley , Fluxo Sanguíneo Regional , Eliminação Renal
16.
Int J Clin Exp Med ; 8(5): 7351-8, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26221275

RESUMO

Klotho is a potential biomarker and therapeutic target in a model of acute kidney injury (AKI) induced in rats by ischemia-reperfusion injury. However, the sensitivity and specificity of serum Klotho for early detecting clinical AKI are unknown. This prospective study evaluated the significance of serum Klotho for early detection of postoperative AKI among adult patients undergoing cardiac valve replacement surgery. Moreover, we also compared the utilities of serum Klotho, serum creatinine and cystatin C in early detection of AKI. There was no marked difference between AKI and non-AKI groups in preoperative serum Klotho levels. Immediately after the operation, serum Klotho decreased significantly in patients with AKl. In spite of the poor specificity, its diagnostic sensitivity was excellent. On postoperative 1 d, with the rapid recovery toward the preoperative level, the ability of serum Klotho for early detecting AKI declined. Changes in serum Klotho levels at every time point among patients without AKI did not reveal any statistical significance. We showed that AKI is a state of transient Klotho deficiency in patients undergoing cardiac valve replacement surgery. Serum Klotho levels were drastically decreased beginning at 0h with ideal ROC-AUC, sensitivity but poor specificity, which didn't exceed 4 h after operation, suggesting that serum Klotho could serve as a potential biomarker for CSA-AKI, especially during the short period after cardiac surgery. A larger multicentre cohort study of population in different ages undergoing on-pump cardiac surgery is required to identify the optimal timing of serum Klotho measurement and the optimal cut-off points for clinical use to further refine the optimal timing for early detection of AKI.

17.
Mater Sci Eng C Mater Biol Appl ; 48: 487-98, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25579950

RESUMO

In this study, a novel hydrogel, chitosan (CS) crosslinked carboxymethyl-ß-cyclodextrin (CM-ß-CD) polymer modified Fe3O4 magnetic nanoparticles was synthesized for delivering hydrophobic anticancer drug 5-fluorouracil (CS-CDpoly-MNPs). Carboxymethyl-ß-cyclodextrin being grafted on the Fe3O4 nanoparticles (CDpoly-MNPs) contributed to an enhancement of adsorption capacities because of the inclusion abilities of its hydrophobic cavity with insoluble anticancer drugs through host-guest interactions. Experimental results indicated that the amounts of crosslinking agent and bonding times played a crucial role in determining morphology features of the hybrid nanocarriers. The nanocarriers exhibited a high loading efficiency (44.7±1.8%) with a high saturation magnetization of 43.8emu/g. UV-Vis spectroscopy results showed that anticancer drug 5-fluorouracil (5-Fu) could be successfully included into the cavities of the covalently linked CDpoly-MNPs. Moreover, the free carboxymethyl groups could enhance the bonding interactions between the covalently linked CDpoly-MNPs and anticancer drugs. In vitro release studies revealed that the release behaviors of CS-CDpoly-MNPs carriers were pH dependent and demonstrated a swelling and diffusion controlled release. A lower pH value led to swelling effect and electrostatic repulsion contributing to the protonation amine impact of NH3(+), and thus resulted in a higher release rate of 5-Fu. The mechanism of 5-Fu encapsulated into the magnetic chitosan nanoparticles was tentatively proposed.


Assuntos
Antimetabólitos Antineoplásicos/química , Quitosana/química , Materiais Revestidos Biocompatíveis/química , Sistemas de Liberação de Medicamentos , Fluoruracila/química , Nanopartículas de Magnetita/química , Concentração de Íons de Hidrogênio , Interações Hidrofóbicas e Hidrofílicas
18.
Pharm Res ; 32(3): 1128-40, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25319098

RESUMO

PURPOSE: Since the vitamin D receptor (VDR) was found to up-regulate cerebral P-glycoprotein expression in vitro and in mice, we extend our findings to rats by assessing the effect of rat Vdr activation on brain efflux of quinidine, a P-gp substrate that is eliminated primarily by cytochrome P450 3a. METHODS: We treated rats with vehicle or the active VDR ligand, 1α,25-dihydroxyvitamin D3 [1,25(OH)2D3] (4.8 or 6.4 nmol/kg i.p. every 2nd day × 4) and examined P-gp expression and cerebral quinidine disposition via microdialysis in control and treatment studies conducted longitudinally in the same rat. RESULTS: The 6.4 nmol/kg 1,25(OH)2D3 dose increased cerebral P-gp expression 1.75-fold whereas hepatic Cyp3a remained unchanged. Although there was no change in systemic clearance elicited by 1,25(OH)2D3, brain extracellular fluid quinidine concentrations were lower in treated rats. We noted that insertion of indwelling catheters increased plasma protein binding of quinidine and serial sampling decreased the blood:plasma concentration ratio, factors that alter distribution ratios in microdialysis studies. After appropriate correction, KECF/P,uu and KECF/B,uu, or ratios of quinidine unbound concentrations in brain extracellular fluid to plasma or blood at steady-state, were more than halved. CONCLUSION: We demonstrate that VDR activation increases cerebral P-gp expression and delimits brain penetration of P-gp substrates.


Assuntos
Membro 1 da Subfamília B de Cassetes de Ligação de ATP/efeitos dos fármacos , Barreira Hematoencefálica/efeitos dos fármacos , Calcitriol/farmacologia , Permeabilidade Capilar/efeitos dos fármacos , Microdiálise , Quinidina/metabolismo , Receptores de Calcitriol/agonistas , Membro 1 da Subfamília B de Cassetes de Ligação de ATP/metabolismo , Animais , Transporte Biológico , Barreira Hematoencefálica/metabolismo , Estado de Consciência , Citocromo P-450 CYP3A/metabolismo , Relação Dose-Resposta a Droga , Masculino , Microssomos Hepáticos/enzimologia , Ligação Proteica , Quinidina/sangue , Ratos Sprague-Dawley , Receptores de Calcitriol/metabolismo , Regulação para Cima
19.
J Pharm Sci ; 102(8): 2440-9, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23744594

RESUMO

A gastric-retentive formulation amenable to dosing in rodents has the potential to enable sustained release in a preclinical setting. This may be useful to provide systemic exposure over a longer duration or to increase duration of exposure for compounds with targets localized in the gastrointestinal tract. Previous work has shown that a mixture of 1% sodium alginate and 0.625% karaya gum in the presence of a calcium chelator can form gels in situ that are gastric retained in rats. The aim of this work was to define the physicochemical boundaries of compounds within this technology and their relation to in vivo release using a series of model compounds with high permeability but varying solubility. In vitro data demonstrated a good correlation between solubility and initial release rates from the gels. In vivo studies were conducted in Sprague-Dawley rats to compare the exposure profile of compounds dosed in gel relative to a standard formulation. In vivo data were consistent with trends from the in vitro studies. These data suggest that, in conjunction with an understanding of compound solubility, sodium alginate/karaya gum gels may be a useful tool to modulate exposure profiles in rodent models in a preclinical setting.


Assuntos
Alginatos/química , Anti-Hipertensivos/farmacocinética , Inibidores de Ciclo-Oxigenase/farmacocinética , Preparações de Ação Retardada/química , Ibuprofeno/farmacocinética , Metoprolol/farmacocinética , Pirazóis/farmacocinética , Sulfonamidas/farmacocinética , Administração Oral , Animais , Anti-Hipertensivos/administração & dosagem , Anti-Hipertensivos/química , Celecoxib , Inibidores de Ciclo-Oxigenase/administração & dosagem , Inibidores de Ciclo-Oxigenase/química , Mucosa Gástrica/metabolismo , Géis/química , Ácido Glucurônico/química , Ácidos Hexurônicos/química , Ibuprofeno/administração & dosagem , Ibuprofeno/química , Masculino , Metoprolol/administração & dosagem , Metoprolol/química , Permeabilidade , Pirazóis/administração & dosagem , Pirazóis/química , Ratos , Ratos Sprague-Dawley , Solubilidade , Sulfonamidas/administração & dosagem , Sulfonamidas/química
20.
J Chromatogr A ; 1284: 155-62, 2013 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-23466204

RESUMO

In recent years, there has been increasing interest in using LC-MS/MS to measure protein drugs (biotherapeutics) in plasma/serum to support pharmacokinetic/toxicokinetic (PK/TK) studies. A number of strategies have been proposed to quantify different types of protein drug candidates in biological matrices. However, the application of LC-MS/MS in biotherapeutics is still very limited in regulated bioanalysis due to practical challenges. In this manuscript, we propose a "data-dependent" approach for the LC-MS/MS support of protein drug candidates, focusing on operational aspects. We have developed and validated a fast, simple and reliable LC-MS/MS method to quantify a protein drug candidate in mouse serum. This method can fit into our current workflow for routine small molecule LC-MS/MS assays with an overall sample preparation time of less than two hours. The method has been demonstrated to be accurate, precise and rugged, and it has been successfully applied to analyze samples from toxicology studies. The results were verified using a ligand binding assay and tested by standard-addition sample reanalysis. In addition, general recommendations for developing and validating an LC-MS/MS assay based on surrogate peptide(s) of protein drug candidates are also proposed for regulated bioanalysis.


Assuntos
Anticorpos Monoclonais/sangue , Cromatografia Líquida/métodos , Descoberta de Drogas/métodos , Espectrometria de Massas em Tandem/métodos , Animais , Calibragem , Camundongos , Fragmentos de Peptídeos/análise , Fragmentos de Peptídeos/química , Padrões de Referência , Reprodutibilidade dos Testes , Projetos de Pesquisa , Tripsina/química
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