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1.
Bioanalysis ; 12(20): 1439-1447, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-33006478

RESUMO

Aim: There is little information in the literature regarding assays for measuring CDH17 in tissues. Numerous studies indicate overexpression of CDH17 in a variety of diseases including hepatocellular carcinoma, colorectal and gastric cancer. Here we present an immunoaffinity enrichment LC-MS/MS approach for analysis of CDH17 in human tissues, plasma and serum as well as preclinical models. Results: CDH17 levels were measured in colon and ileum tissues from healthy donors and inflamed tissues from patients with Ulcerative Colitus or Crohn's disease. Applicability of the immunocapture LC-MS/MS approach is demonstrated for colon tissues from non-diseased mouse and cynomolgus monkey. Conclusion: The analytical approaches discussed here are suitable for quantitation of CDH17 in various tissues to enable both preclinical and clinical assessment.

2.
Bioanalysis ; 12(18): 1311-1324, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32945691

RESUMO

Background: S1PR1, a G protein-coupled receptor (GPCR) protein, is a therapeutic target for treatment of autoimmune diseases. As a potential biomarker for drug effect and patient stratification, it is of great significance to measure it in biological samples. However, due to the hydrophobic nature of S1PR1 and the difficulties in extraction and solubilization, as well as low expression levels, quantitative determination of S1PR1 remains challenging. Results: In this work, a peptide immunoaffinity LC-MS/MS method was developed to quantify S1PR1 in biopsy-sized colon samples with an LLOQ of 7.81 pM. Conclusion: Peptide immunoaffinity LC-MS/MS based strategy has achieved the desired sensitivity for low abundance S1PR1, and the same strategy could be applied to quantify S1PR1 in multiple species and other GPCR proteins.

3.
Rapid Commun Mass Spectrom ; 34(20): e8896, 2020 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-32666620

RESUMO

RATIONALE: High tumor expression of programmed cell death protein (PD1) and programmed death-ligand 1 (PD-L1) is thought to be associated with positive clinical outcomes after treatment with anti-PD1 or anti-PD-L1 agents. Several sensitive methods based on immunohistochemistry, ligand binding assay (LBA), and liquid chromatography/mass spectrometry involving the measurement of PD1 and PD-L1 expression have been reported. Here, we expand on the characterization of different tumor types using a highly specific, sensitive, and robust immunoaffinity liquid chromatography/tandem mass spectrometry (IA-LC/MS/MS)-based method for the simultaneous quantitation of PD1 and PD-L1 in tumor tissues. METHODS: Human tumor tissue samples were homogenized using a Precellys Evolution homogenizer. The samples were incubated with anti-PD1 and anti-PD-L1 capture polyclonal antibodies, which were bound to magnetic beads. Following enrichment, samples were digested with trypsin. A Waters iKEY HSS T3 1.8 um (150 µm × 100 mm) column with a gradient flow rate of 3 µL/min was used for chromatographic separation, and a Waters TQ-S triple quadrupole mass spectrometer was used for detection. Selected reaction monitoring (SRM) transitions with unit resolution for precursor/product ion masses were optimized for PD1 and PD-L1 surrogate peptides. RESULTS: The surrogate peptides LAAFPEDR for PD1 and FTVTVPK for PD-L1 yielded the most intense SRM transitions at m/z 459.7 > 516.2 and m/z 396.2 > 543.3, respectively, and thus were selected for the quantitation of PD1 and PD-L1. The lower limit of quantitation for PD1 and PD-L1 was 0.062 ng/mL with an assay range up to 10 ng/mL. Using this method, human PD1 and PD-L1 were detected and quantified from four different types of tumor tissues. The data show that PD1 expression level was highly correlated with that of PD-L1 in all tumor tissues analyzed here. CONCLUSIONS: A highly specific and sensitive immunoaffinity microflow LC/MS/MS method for the simultaneous quantification of PD1 and PD-L1 in tumor tissues was developed and implemented. This method combines the advantage of immuno-capture for analyte enrichment with the high specificity of detection of multiple surrogate peptides by LC/MS/MS. The quantification of PD1 and PD-L1 co-expression in tumor could help evaluate their role in assessing tumor type selection and patient stratification.

4.
Anal Biochem ; 602: 113766, 2020 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-32389692

RESUMO

The S100A1 protein is a target of interest for the treatment of heart failure as it has been previously reported to be depleted in failing cardiomyocytes. A gene therapy approach leading to increased expression levels of the protein directly in the heart could potentially lead to restoration of contractile function and improve overall cell survival. S100A1 is a relatively small soluble protein that is extremely well conserved across species with only a single amino acid difference between the sequences in human and pig, a commonly used pre-clinical model for evaluation of efficacy, biodistribution and safety for cardiac-directed gene therapy approaches. This high homology presents a bioanalytical challenge for the accurate detection and quantitation of both endogenous (pig) and exogenous (human) transduced S100A1 proteins post treatment using a human S100A1 gene therapy in pigs. Here we present a sensitive and selective LC-MS/MS approach that can easily differentiate and simultaneously quantitate both human and pig S100A1 proteins. Additionally, we report on a detailed profiling of S100A1 protein in various pig tissues, a comprehensive evaluation of S100A1 distribution in pig hearts and a comparison to S100A1 levels in human cardiac samples.

5.
Bioanalysis ; 11(22): 2029-2048, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31808716

RESUMO

The 2019 13th Workshop on Recent Issues in Bioanalysis (WRIB) took place in New Orleans, LA, USA on April 1-5, 2019 with an attendance of over 1000 representatives from pharmaceutical/biopharmaceutical companies, biotechnology companies, contract research organizations and regulatory agencies worldwide. WRIB was once again a 5-day, week-long event - a full immersion week of bioanalysis, biomarkers, immunogenicity and gene therapy. As usual, it was specifically designed to facilitate sharing, reviewing, discussing and agreeing on approaches to address the most current issues of interest including both small- and large-molecule bioanalysis involving LCMS, hybrid LBA/LCMS, LBA cell-based/flow cytometry assays and qPCR approaches. This 2019 White Paper encompasses recommendations emerging from the extensive discussions held during the workshop, and is aimed to provide the bioanalytical community with key information and practical solutions on topics and issues addressed, in an effort to enable advances in scientific excellence, improved quality and better regulatory compliance. Due to its length, the 2019 edition of this comprehensive White Paper has been divided into three parts for editorial reasons. This publication (Part 1) covers the recommendations on Innovation in Small Molecules and Oligonucleotides & Mass Spec Method Development Strategies for Large Molecules Bioanalysis. Part 2 (2018 FDA BMV Guidance, 2019 ICH M10 BMV Draft Guideline and regulatory agencies' input on bioanalysis, biomarkers, immunogenicity and gene therapy) and Part 3 (New Insights in Biomarkers Assays Validation, Current & Effective Strategies for Critical Reagent Management, Flow Cytometry Validation in drug discovery & development & CLSI H62, Interpretation of the 2019 FDA Immunogenicity Guidance and The Gene Therapy Bioanalytical Challenges) are published in volume 11 of Bioanalysis, issues 23 and 24 (2019), respectively.


Assuntos
Cromatografia Líquida/métodos , Invenções , Espectrometria de Massas/métodos , Oligonucleotídeos/análise , Bibliotecas de Moléculas Pequenas/análise
6.
PLoS One ; 14(3): e0212670, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30913212

RESUMO

Immunotherapy has fundamentally changed the landscape of cancer treatment. Despite the encouraging results with the checkpoint modulators, response rates vary widely across tumor types, with a majority of patients exhibiting either primary resistance without a significant initial response to treatment or acquired resistance with subsequent disease progression. Hematopoietic progenitor kinase 1 (HPK1) is predominantly expressed in hematopoietic cell linages and serves as a negative regulator in T cells and dendritic cells (DC). While HPK1 gene knockout (KO) studies suggest its role in anti-tumor immune responses, the involvement of kinase activity and thereof its therapeutic potential remain unknown. To investigate the potential of pharmacological intervention using inhibitors of HPK1, we generated HPK1 kinase dead (KD) mice which carry a single loss-of-function point mutation in the kinase domain and interrogated the role of kinase activity in immune cells in the context of suppressive factors or the tumor microenvironment (TME). Our data provide novel findings that HKP1 kinase activity is critical in conferring suppressive functions of HPK1 in a wide range of immune cells including CD4+, CD8+, DC, NK to Tregs, and inactivation of kinase domain was sufficient to elicit robust anti-tumor immune responses. These data support the concept that an HPK1 small molecule kinase inhibitor could serve as a novel agent to provide additional benefit in combination with existing immunotherapies, particularly to overcome resistance to current treatment regimens.


Assuntos
Imunidade Celular , Vigilância Imunológica , Linfócitos/imunologia , Neoplasias Experimentais/imunologia , Proteínas Serina-Treonina Quinases/imunologia , Microambiente Tumoral/imunologia , Animais , Linhagem Celular Tumoral , Linfócitos/patologia , Camundongos , Camundongos Mutantes , Neoplasias Experimentais/genética , Mutação Puntual , Proteínas Serina-Treonina Quinases/genética , Microambiente Tumoral/genética
7.
Anal Biochem ; 568: 41-50, 2019 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-30605634

RESUMO

Apelin, the endogenous ligand for the APJ receptor, has generated interest due to its beneficial effects on the cardiovascular system. Synthesized as a 77 amino acid preproprotein, apelin is post-translationally cleaved to a series of shorter peptides. Though (Pyr)1apelin-13 represents the major circulating form in plasma, it is highly susceptible to proteolytic degradation and has an extremely short half-life, making it challenging to quantify. Literature reports of apelin levels in rodents have historically been determined with commercial ELISA kits which suffer from a lack of selectivity, recognizing a range of active and inactive isoforms of apelin peptide. (Pyr)1apelin-13 has demonstrated beneficial hemodynamic effects in humans, and we wished to evaluate if similar effects could be measured in pre-clinical models. Despite development of a highly selective LC/MS/MS method, in rodent studies where (Pyr)1apelin-13 was administered exogenously the peptide was not detectable until a detailed stabilization protocol was implemented during blood collection. Further, the inherent high clearance of (Pyr)1apelin-13 required an extended release delivery system to enable chronic dosing. The ability to deliver sustained doses and stabilize (Pyr)1apelin-13 in plasma allowed us to demonstrate for the first time the link between systemic concentration of apelin and its pharmacological effects in animal models.


Assuntos
Peptídeos e Proteínas de Sinalização Intercelular/farmacocinética , Peptídeos/análise , Animais , Cromatografia Líquida , Cães , Ensaio de Imunoadsorção Enzimática , Hemodinâmica , Humanos , Peptídeos e Proteínas de Sinalização Intercelular/sangue , Peptídeos e Proteínas de Sinalização Intercelular/metabolismo , Masculino , Camundongos , Peptídeos/metabolismo , Ratos , Ratos Sprague-Dawley , Espectrometria de Massas em Tandem
8.
J Pharmacol Exp Ther ; 368(1): 136-145, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30361237

RESUMO

Plasma pyridoxic acid (PDA) and homovanillic acid (HVA) were recently identified as novel endogenous biomarkers of organic anion transporter (OAT) 1/3 function in monkeys. Consequently, this clinical study assessed the dynamic changes and utility of plasma PDA and HVA as an initial evaluation of OAT1/3 inhibition in early-phase drug development. The study was designed as a single-dose randomized, three-phase, crossover study; 14 Indian healthy volunteers received probenecid (PROB) (1000 mg orally) alone, furosemide (FSM) (40 mg orally) alone, or FSM 1 hour after receiving PROB (40 and 1000 mg orally) on days 1, 8, and 15, respectively. PDA and HVA plasma concentrations remained stable over time in the prestudy and FSM groups. Administration of PROB significantly increased the area under the plasma concentration-time curve (AUC) of PDA by 3.1-fold (dosed alone; P < 0.05), and 3.2-fold (coadministered with FSM; P < 0.01), compared with the prestudy and FSM groups, respectively. The corresponding increase in HVA AUC was 1.8-fold (P > 0.05) and 2.1-fold (P < 0.05), respectively. The increases in PDA AUC are similar to those in FSM AUC, whereas those of HVA are smaller (3.1-3.2 and 1.8-2.1 vs. 3.3, respectively). PDA and HVA renal clearance (CL R) values were decreased by PROB to smaller extents compared with FSM (0.35-0.37 and 0.67-0.73 vs. 0.23, respectively). These data demonstrate that plasma PDA is a promising endogenous biomarker for OAT1/3 function and that its plasma exposure responds in a similar fashion to FSM upon OAT1/3 inhibition by PROB. The magnitude and variability of response in PDA AUC and CL R values between subjects is more favorable relative to HVA.


Assuntos
Proteína 1 Transportadora de Ânions Orgânicos/fisiologia , Transportadores de Ânions Orgânicos Sódio-Independentes/fisiologia , Ácido Piridóxico/sangue , Adolescente , Adulto , Biomarcadores/sangue , Estudos Cross-Over , Voluntários Saudáveis , Humanos , Masculino , Pessoa de Meia-Idade , Reprodutibilidade dos Testes , Adulto Jovem
9.
Bioanalysis ; 10(9): 633-644, 2018 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-29749254

RESUMO

AIM: Coproporphyrins (CP-I and CP-III) have been identified as possible biomarkers to predict human hepatic organic anion-transporting polypeptides-mediated-drug-interactions for a new drug entering clinical development. RESULTS: The method is applicable to quantify plasma CP-I and CP-III within 0.078-15.0 nM. The results identify and address a number of challenges encountered with porphyrin assays such as photodegradation and interferences. To overcome interferences from ubiquitous porphyrins, a surrogate matrix was used to prepare calibration standards. Quality controls were prepared in plasma and surrogate matrix to ensure parallelism between surrogate matrix and plasma. CONCLUSION: A robust UHPLC-MS/MS assay was developed and validated for CP-I and CP-III in plasma, and is currently applied to clinical studies to confirm suitability of Coproporphyrins as a potential substitute for drug-drug interaction study.


Assuntos
Biomarcadores Farmacológicos/sangue , Cromatografia Líquida de Alta Pressão/métodos , Coproporfirinas/sangue , Transportadores de Ânions Orgânicos/metabolismo , Espectrometria de Massas em Tandem/métodos , Biomarcadores Farmacológicos/química , Coproporfirinas/química , Desenho de Fármacos , Interações Medicamentosas , Humanos , Transportadores de Ânions Orgânicos/química , Rifampina/sangue , Rifampina/química , Rosuvastatina Cálcica/sangue , Rosuvastatina Cálcica/química
10.
Drug Metab Dispos ; 46(2): 178-188, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-29162614

RESUMO

Perturbation of organic anion transporter (OAT) 1- and OAT3-mediated transport can alter the exposure, efficacy, and safety of drugs. Although there have been reports of the endogenous biomarkers for OAT1/3, none of these have all of the characteristics required for a clinical useful biomarker. Cynomolgus monkeys were treated with intravenous probenecid (PROB) at a dose of 40 mg/kg in this study. As expected, PROB increased the area under the plasma concentration-time curve (AUC) of coadministered furosemide, a known substrate of OAT1 and OAT3, by 4.1-fold, consistent with the values reported in humans (3.1- to 3.7-fold). Of the 233 plasma metabolites analyzed using a liquid chromatography-tandem mass spectrometry (LC-MS/MS)-based metabolomics method, 29 metabolites, including pyridoxic acid (PDA) and homovanillic acid (HVA), were significantly increased after either 1 or 3 hours in plasma from the monkeys pretreated with PROB compared with the treated animals. The plasma of animals was then subjected to targeted LC-MS/MS analysis, which confirmed that the PDA and HVA AUCs increased by approximately 2- to 3-fold by PROB pretreatments. PROB also increased the plasma concentrations of hexadecanedioic acid (HDA) and tetradecanedioic acid (TDA), although the increases were not statistically significant. Moreover, transporter profiling assessed using stable cell lines constitutively expressing transporters demonstrated that PDA and HVA are substrates for human OAT1, OAT3, OAT2 (HVA), and OAT4 (PDA), but not OCT2, MATE1, MATE2K, OATP1B1, OATP1B3, and sodium taurocholate cotransporting polypeptide. Collectively, these findings suggest that PDA and HVA might serve as blood-based endogenous probes of cynomolgus monkey OAT1 and OAT3, and investigation of PDA and HVA as circulating endogenous biomarkers of human OAT1 and OAT3 function is warranted.


Assuntos
Biomarcadores/sangue , Ácido Homovanílico/sangue , Proteína 1 Transportadora de Ânions Orgânicos/metabolismo , Transportadores de Ânions Orgânicos Sódio-Independentes/metabolismo , Ácido Piridóxico/sangue , Animais , Transporte Biológico/fisiologia , Linhagem Celular , Células HEK293 , Humanos , Macaca fascicularis , Metabolômica/métodos , Probenecid/metabolismo
12.
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
13.
Anal Chem ; 89(9): 5115-5123, 2017 05 02.
Artigo em Inglês | MEDLINE | ID: mdl-28383906

RESUMO

We demonstrate a novel strategy using affinity extraction (AE) LC-MS to directly measure drug exposure and target engagement, two critical pharmacological questions, with a single assay. The assay measures total drug and target concentration at the site of therapeutic action, as well as the amount of target bound to drug. The case study presented applies the strategy to measure drug engagement of a membrane bound receptor (CD40) that is critical to immune regulation in colon biopsies collected from monkey dosed with an anti-CD40 antibody. Unlike other techniques that measure receptor occupancy, such as flow cytometry, this technique does not rely on viable cells allowing measurement of frozen samples in a remote setting from the clinic.


Assuntos
Anticorpos/análise , Antígenos CD40/análise , Colo/química , Membrana Mucosa/química , Animais , Anticorpos/imunologia , Antígenos CD40/imunologia , Cromatografia de Afinidade/métodos , Humanos , Macaca fascicularis , Ratos , Espectrometria de Massas em Tandem/métodos
14.
Obesity (Silver Spring) ; 25(6): 1069-1076, 2017 06.
Artigo em Inglês | MEDLINE | ID: mdl-28452429

RESUMO

OBJECTIVE: Characteristic pathological changes define the progression of steatosis to nonalcoholic steatohepatitis (NASH) and are correlated to metabolic pathways. A common rodent model of NASH is the methionine and choline deficient (MCD) diet. The objective of this study was to perform full metabolomic analyses on liver samples to determine which pathways are altered most pronouncedly in this condition in humans, and to compare these changes to rodent models of nonalcoholic fatty liver disease (NAFLD). METHODS: A principal component analysis for all 91 metabolites measured indicated that metabolome perturbation is greater and less varied for humans than for rodents. RESULTS: Metabolome changes in human and rat NAFLD were greatest for the amino acid and bile acid metabolite families (e.g., asparagine, citrulline, gamma-aminobutyric acid, lysine); although, in many cases, the trends were reversed when compared between species (cholic acid, betaine). CONCLUSIONS: Overall, these results indicate that metabolites of specific pathways may be useful biomarkers for NASH progression, although these markers may not correspond to rodent NASH models. The MCD model may be useful when studying certain end points of NASH; however, the metabolomics results indicate important differences between humans and rodents in the biochemical pathogenesis of the disease.


Assuntos
Metabolômica/métodos , Obesidade/complicações , Animais , Dieta , Progressão da Doença , Humanos , Fígado/patologia , Masculino , Hepatopatia Gordurosa não Alcoólica/metabolismo , Ratos , Ratos Sprague-Dawley
15.
Cell Metab ; 24(2): 223-33, 2016 08 09.
Artigo em Inglês | MEDLINE | ID: mdl-27508871

RESUMO

The development of LXR agonists for the treatment of coronary artery disease has been challenged by undesirable properties in animal models. Here we show the effects of an LXR agonist on lipid and lipoprotein metabolism and neutrophils in human subjects. BMS-852927, a novel LXRß-selective compound, had favorable profiles in animal models with a wide therapeutic index in cynomolgus monkeys and mice. In healthy subjects and hypercholesterolemic patients, reverse cholesterol transport pathways were induced similarly to that in animal models. However, increased plasma and hepatic TG, plasma LDL-C, apoB, apoE, and CETP and decreased circulating neutrophils were also evident. Furthermore, similar increases in LDL-C were observed in normocholesterolemic subjects and statin-treated patients. The primate model markedly underestimated human lipogenic responses and did not predict human neutrophil effects. These studies demonstrate both beneficial and adverse LXR agonist clinical responses and emphasize the importance of further translational research in this area.


Assuntos
Movimento Celular , Imidazóis/efeitos adversos , Imidazóis/farmacologia , Metabolismo dos Lipídeos , Lipoproteínas/metabolismo , Receptores X do Fígado/agonistas , Neutrófilos/metabolismo , Transportador 1 de Cassete de Ligação de ATP/genética , Transportador 1 de Cassete de Ligação de ATP/metabolismo , Membro 1 da Subfamília G de Transportadores de Cassetes de Ligação de ATP/genética , Membro 1 da Subfamília G de Transportadores de Cassetes de Ligação de ATP/metabolismo , Tecido Adiposo/metabolismo , Adolescente , Adulto , Animais , Movimento Celular/efeitos dos fármacos , Colesterol/sangue , Colesterol/metabolismo , Voluntários Saudáveis , Humanos , Inibidores de Hidroximetilglutaril-CoA Redutases/farmacologia , Inibidores de Hidroximetilglutaril-CoA Redutases/uso terapêutico , Hipercolesterolemia/sangue , Hipercolesterolemia/tratamento farmacológico , Imidazóis/uso terapêutico , Contagem de Leucócitos , Lipoproteínas/sangue , Macaca fascicularis , Macrófagos/metabolismo , Masculino , Camundongos Endogâmicos C57BL , Sistema Fagocitário Mononuclear/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Ratos , Triglicerídeos/sangue , Adulto Jovem
16.
Gut Microbes ; 7(4): 313-322, 2016 07 03.
Artigo em Inglês | MEDLINE | ID: mdl-27355107

RESUMO

We previously reported quantitation of gut microbiota in a panel of 89 different inbred strains of mice, and we now examine the question of sex differences in microbiota composition. When the total population of 689 mice was examined together, several taxa exhibited significant differences in abundance between sexes but a larger number of differences were observed at the single strain level, suggesting that sex differences can be obscured by host genetics and environmental factors. We also examined a subset of mice on chow and high fat diets and observed sex-by-diet interactions. We further investigated the sex differences using gonadectomized and hormone treated mice from 3 different inbred strains. Principal coordinate analysis with unweighted UniFrac distances revealed very clear effects of gonadectomy and hormone replacement on microbiota composition in all 3 strains. Moreover, bile acid analyses showed gender-specific differences as well as effects of gonodectomy, providing one possible mechanism mediating sex differences in microbiota composition.


Assuntos
Microbioma Gastrointestinal , Trato Gastrointestinal/microbiologia , Hormônios/metabolismo , Camundongos/microbiologia , Animais , Ácidos e Sais Biliares/metabolismo , Comportamento Alimentar , Feminino , Masculino , Camundongos/fisiologia , Fatores Sexuais
17.
J Pharmacol Exp Ther ; 358(3): 397-404, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-27317801

RESUMO

In the present study, an open-label, three-treatment, three-period clinical study of rosuvastatin (RSV) and rifampicin (RIF) when administered alone and in combination was conducted in 12 male healthy subjects to determine if coproporphyrin I (CP-I) and coproporphyrin III (CP-III) could serve as clinical biomarkers for organic anion transporting polypeptide 1B1 (OATP1B1) and 1B3 that belong to the solute carrier organic anion gene subfamily. Genotyping of the human OATP1B1 gene was performed in all 12 subjects and confirmed absence of OATP1B1*5 and OATP1B1*15 mutations. Average plasma concentrations of CP-I and CP-III prior to drug administration were 0.91 ± 0.21 and 0.15 ± 0.04 nM, respectively, with minimum fluctuation over the three periods. CP-I was passively eliminated, whereas CP-III was actively secreted from urine. Administration of RSV caused no significant changes in the plasma and urinary profiles of CP-I and CP-III. RIF markedly increased the maximum plasma concentration (Cmax) of CP-I and CP-III by 5.7- and 5.4-fold (RIF) or 5.7- and 6.5-fold (RIF+RSV), respectively, as compared with the predose values. The area under the plasma concentration curves from time 0 to 24 h (AUC0-24h) of CP-I and CP-III with RIF and RSV increased by 4.0- and 3.3-fold, respectively, when compared with RSV alone. In agreement with this finding, Cmax and AUC0-24h of RSV increased by 13.2- and 5.0-fold, respectively, when RIF was coadministered. Collectively, we conclude that CP-I and CP-III in plasma and urine can be appropriate endogenous biomarkers specifically and reliably reflecting OATP inhibition, and thus the measurement of these molecules can serve as a useful tool to assess OATP drug-drug interaction liabilities in early clinical studies.


Assuntos
Coproporfirinas/sangue , Coproporfirinas/urina , Transportadores de Ânions Orgânicos/antagonistas & inibidores , Rifampina/farmacologia , Rosuvastatina Cálcica/farmacologia , Adulto , Biomarcadores/sangue , Biomarcadores/urina , Interações Medicamentosas , Humanos , Masculino , Pessoa de Meia-Idade , Rifampina/farmacocinética , Rosuvastatina Cálcica/farmacocinética , Adulto Jovem
18.
Anal Biochem ; 503: 71-8, 2016 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-27033006

RESUMO

The growing field of biomarker bioanalysis by liquid chromatography mass spectrometry (LC-MS) is challenged with the selection of suitable matrices to construct relevant and valid calibration curves resulting in not only precise but also accurate data. Because surrogate matrices are often employed with the associated concerns about the accuracy of the obtained data, here we present an assay using surrogate analytes in naive biological matrices. This approach is illustrated with the analysis of endogenous bile acids (e-BAs) in serum and plasma using stable isotope-labeled (SIL) analogues as calibration standards to address the matrix concerns. Several deuterated BAs (d-BAs) were used as standards representing respectively grouped e-BAs with structural similarity allowing for the simultaneous bioanalysis of 16 e-BA. The utility of this LC-MS assay employing d-BAs is demonstrated with the analysis of samples resultant of a controlled metabolomics study where a cohort of rats was fed/fasted to investigate the change of e-BAs dependent on food consumption and fasting time.


Assuntos
Ácidos e Sais Biliares/sangue , Ácidos e Sais Biliares/metabolismo , Marcação por Isótopo , Metabolômica , Animais , Ácidos e Sais Biliares/química , Cromatografia Líquida , Humanos , Espectrometria de Massas , Estrutura Molecular , Ratos
19.
Amino Acids ; 47(3): 603-15, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25534430

RESUMO

Nonalcoholic fatty liver disease (NAFLD) is a globally widespread disease of increasing clinical significance. The pathological progression of the disease from simple steatosis to nonalcoholic steatohepatitis (NASH) has been well defined, however, the contribution of altered branched chain amino acid metabolomic profiles to the progression of NAFLD is not known. The three BCAAs: leucine, isoleucine and valine are known to mediate activation of several important hepatic metabolic signaling pathways ranging from insulin signaling to glucose regulation. The purpose of this study is to profile changes in hepatic BCAA metabolite levels with transcriptomic changes in the progression of human NAFLD to discover novel mechanisms of disease progression. Metabolomic and transcriptomic data sets representing the spectrum of human NAFLD (normal, steatosis, NASH fatty, and NASH not fatty livers) were utilized for this study. During the transition from steatosis to NASH, increases in the levels of leucine (127% of normal), isoleucine (139%), and valine (147%) were observed. Carnitine metabolites also exhibited significantly elevated profiles in NASH fatty and NASH not fatty samples and included propionyl, hexanoyl, lauryl, acetyl and butyryl carnitine. Amino acid and BCAA metabolism gene sets were significantly enriched among downregulated genes during NASH. These cumulative alterations in BCAA metabolite and amino acid metabolism gene profiles represent adaptive physiological responses to disease-induced hepatic stress in NASH patients.


Assuntos
Isoleucina/metabolismo , Leucina/metabolismo , Hepatopatia Gordurosa não Alcoólica/metabolismo , Valina/metabolismo , Carnitina/genética , Carnitina/metabolismo , Feminino , Perfilação da Expressão Gênica , Humanos , Isoleucina/genética , Leucina/genética , Masculino , Metabolômica , Hepatopatia Gordurosa não Alcoólica/genética , Transdução de Sinais/genética , Valina/genética
20.
J Lipid Res ; 55(8): 1784-96, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24872406

RESUMO

Lysophosphatidic acids (LPAs) are biologically active signaling molecules involved in the regulation of many cellular processes and have been implicated as potential mediators of fibroblast recruitment to the pulmonary airspace, pointing to possible involvement of LPA in the pathology of pulmonary fibrosis. LPAs have been measured in various biological matrices and many challenges involved with their analyses have been documented. However, little published information is available describing LPA levels in human bronchoalveolar lavage fluid (BALF). We therefore conducted detailed investigations into the effects of extensive sample handling and sample preparation conditions on LPA levels in human BALF. Further, targeted lipid profiling of human BALF and plasma identified the most abundant lysophospholipids likely to interfere with LPA measurements. We present the findings from these investigations, highlighting the importance of well-controlled sample handling for the accurate quantitation of LPA. Further, we show that chromatographic separation of individual LPA species from their corresponding lysophospholipid species is critical to avoid reporting artificially elevated levels. The optimized sample preparation and LC/MS/MS method was qualified using a stable isotope-labeled LPA as a surrogate calibrant and used to determine LPA levels in human BALF and plasma from a Phase 0 clinical study comparing idiopathic pulmonary fibrosis patients to healthy controls.


Assuntos
Líquido da Lavagem Broncoalveolar/química , Fibrose Pulmonar Idiopática/metabolismo , Lisofosfolipídeos/metabolismo , Cromatografia Líquida/métodos , Feminino , Humanos , Masculino , Espectrometria de Massas/métodos
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