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1.
J Med Chem ; 63(4): 1660-1670, 2020 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-31990537

RESUMO

Endothelial lipase (EL) hydrolyzes phospholipids in high-density lipoprotein (HDL) resulting in reduction in plasma HDL levels. Studies with murine transgenic, KO, or loss-of-function variants strongly suggest that inhibition of EL will lead to sustained plasma high-density lipoprotein cholesterol (HDL-C) increase and, potentially, a reduced cardiovascular disease (CVD) risk. Herein, we describe the discovery of a series of oxadiazole ketones, which upon optimization, led to the identification of compound 12. Compound 12 was evaluated in a mouse pharmacodynamics (PD) model and demonstrated a 56% increase in plasma HDL-C. In a mouse reverse cholesterol transport study, compound 12 stimulated cholesterol efflux by 53% demonstrating HDL-C functionality.

3.
Bioorg Med Chem Lett ; 29(15): 1918-1921, 2019 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-31176700

RESUMO

A low level of high density lipoprotein (HDL) is an independent risk factor for cardiovascular disease. HDL reduces inflammation and plays a central role in reverse cholesterol transport, where cholesterol is removed from peripheral tissues and atherosclerotic plaque. One approach to increase plasma HDL is through inhibition of endothelial lipase (EL). EL hydrolyzes phospholipids in HDL resulting in reduction of plasma HDL. A series of benzothiazole sulfone amides was optimized for EL inhibition potency, lipase selectivity and improved pharmacokinetic profile leading to the identification of Compound 32. Compound 32 was evaluated in a mouse pharmacodynamic model and found to show no effect on HDL cholesterol level despite achieving targeted plasma exposure (Ctrough > 15 fold over mouse plasma EL IC50 over 4 days).

4.
ACS Med Chem Lett ; 9(7): 673-678, 2018 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-30034599

RESUMO

Screening of a small set of nonselective lipase inhibitors against endothelial lipase (EL) identified a potent and reversible inhibitor, N-(3-(3,4-dichlorophenyl)propyl)-3-hydroxy-1-methyl-2-oxo-1,2-dihydropyridine-4-carboxamide (5; EL IC50 = 61 nM, ELHDL IC50 = 454 nM). Deck mining identified a related hit, N-(3-(3,4-dichlorophenyl)propyl)-4-hydroxy-1-methyl-5-oxo-2,5-dihydro-1H-pyrrole-3-carboxamide (6a; EL IC50 = 41 nM, ELHDL IC50 = 1760 nM). Both compounds were selective against lipoprotein lipase (LPL) but nonselective versus hepatic lipase (HL). Optimization of compound 6a for EL inhibition using HDL as substrate led to N-(4-(3,4-dichlorophenyl)butan-2-yl)-1-ethyl-4-hydroxy-5-oxo-2,5-dihydro-1H-pyrrole-3-carboxamide (7c; EL IC50 = 148 nM, ELHDL IC50 = 218 nM) having improved PK over compound 6a, providing a tool molecule to test for the ability to increase HDL-cholesterol (HDL-C) levels in vivo using a reversible EL inhibitor. Compound 7c did not increase HDL-C in vivo despite achieving plasma exposures targeted on the basis of enzyme activity and protein binding demonstrating the need to develop more physiologically relevant in vitro assays to guide compound progression for in vivo evaluation.

5.
ACS Med Chem Lett ; 9(12): 1175-1180, 2018 Dec 13.
Artigo em Inglês | MEDLINE | ID: mdl-30613322

RESUMO

Myeloperoxidase (MPO) generates reactive oxygen species that potentially contribute to many chronic inflammatory diseases. A recently reported triazolopyrimidine MPO inhibitor was optimized to improve acid stability and remove methyl guanine methyl transferase (MGMT) activity. Multiple synthetic routes were explored that allowed rapid optimization of a key benzyl ether side chain. Crystal structures of inhibitors bound to the MPO active site demonstrated alternate binding modes and guided rational design of MPO inhibitors. Thioether 36 showed significant inhibition of MPO activity in an acute mouse inflammation model after oral dosing.

6.
ACS Med Chem Lett ; 9(12): 1263-1268, 2018 Dec 13.
Artigo em Inglês | MEDLINE | ID: mdl-30613337

RESUMO

Endothelial lipase (EL) selectively metabolizes high density lipoprotein (HDL) particles. Inhibition of EL has been shown to increase HDL concentration in preclinical animal models and was targeted as a potential treatment of atherosclerosis. We describe the introduction of an α-sulfone moiety to a benzothiazole series of EL inhibitors resulting in increased potency versus EL. Optimization for selectivity versus hepatic lipase and pharmacokinetic properties resulted in the discovery of 24, which showed good in vitro potency and bioavailability but, unexpectedly, did not increase HDL in the mouse pharmacodynamic model at the target plasma exposure.

7.
Medchemcomm ; 8(11): 2093-2099, 2017 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-30108726

RESUMO

Myeloperoxidase, a mammalian peroxidase involved in the immune system as an anti-microbial first responder, can produce hypochlorous acid in response to invading pathogens. Myeloperoxidase has been implicated in several chronic pathological diseases due to the chronic production of hypochlorous acid, as well as other reactive radical species. A high throughput screen and triaging protocol was developed to identify a reversible inhibitor of myeloperoxidase toward the potential treatment of chronic diseases such as atherosclerosis. The identification and characterization of a reversible myeloperoxidase inhibitor, 7-(benzyloxy)-3H-[1,2,3]triazolo[4,5-d]pyrimidin-5-amine is described.

8.
Anal Biochem ; 501: 56-65, 2016 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-26874021

RESUMO

Kynurenine aminotransferases convert kynurenine to kynurenic acid and play an important role in the tryptophan degradation pathway. Kynurenic acid levels in brain have been hypothesized to be linked to a number of central nervous system (CNS) disorders. Kynurenine aminotransferase II (KATII) has proven to be a key modulator of kynurenic acid levels in brain and, thus, is an attractive target to treat CNS diseases. A sensitive, high-throughput, label-free RapidFire mass spectrometry assay has been developed for human KATII. Unlike other assays, this method is directly applicable to KATII enzymes from different animal species, which allows us to select proper animal model(s) to evaluate human KATII inhibitors. We also established a coupled fluorescence assay for human KATII. The short assay time and kinetic capability of the fluorescence assay provide a useful tool for orthogonal inhibitor validation and mechanistic studies.


Assuntos
Avaliação Pré-Clínica de Medicamentos/métodos , Ensaios Enzimáticos/métodos , Inibidores Enzimáticos/farmacologia , Transaminases/antagonistas & inibidores , Encéfalo/efeitos dos fármacos , Encéfalo/metabolismo , Doenças do Sistema Nervoso Central/tratamento farmacológico , Doenças do Sistema Nervoso Central/enzimologia , Inibidores Enzimáticos/química , Ensaios de Triagem em Larga Escala/métodos , Humanos , Ácido Cinurênico/metabolismo , Espectrometria de Massas/métodos , Espectrometria de Fluorescência/métodos , Transaminases/metabolismo
9.
J Biol Chem ; 289(48): 33456-68, 2014 Nov 28.
Artigo em Inglês | MEDLINE | ID: mdl-25301950

RESUMO

HCV infection is an urgent global health problem that has triggered a drive to discover therapies that specifically target the virus. BMS-791325 is a novel direct antiviral agent specifically targeting HCV NS5B, an RNA-dependent RNA polymerase. Robust viral clearance of HCV was observed in infected patients treated with BMS-791325 in combination with other anti-HCV agents in Phase 2 clinical studies. Biochemical and biophysical studies revealed that BMS-791325 is a time-dependent, non-competitive inhibitor of the polymerase. Binding studies with NS5B genetic variants (WT, L30S, and P495L) exposed a two-step, slow binding mechanism, but details of the binding mechanism differed for each of the polymerase variants. For the clinically relevant resistance variant (P495L), the rate of initial complex formation and dissociation is similar to WT, but the kinetics of the second step is significantly faster, showing that this variant impacts the final tight complex. The resulting shortened residence time translates into the observed decrease in inhibitor potency. The L30S variant has a significantly different profile. The rate of initial complex formation and dissociation is 7-10 times faster for the L30S variant compared with WT; however, the forward and reverse rates to form the final complex are not significantly different. The impact of the L30S variant on the inhibition profile and binding kinetics of BMS-791325 provides experimental evidence for the dynamic interaction of fingers and thumb domains in an environment that supports the formation of active replication complexes and the initiation of RNA synthesis.


Assuntos
Antivirais/química , Benzazepinas/química , Hepacivirus/enzimologia , Indóis/química , RNA Replicase/antagonistas & inibidores , Proteínas não Estruturais Virais/antagonistas & inibidores , Substituição de Aminoácidos , Antivirais/farmacologia , Benzazepinas/uso terapêutico , Hepatite C/tratamento farmacológico , Hepatite C/enzimologia , Humanos , Indóis/uso terapêutico , Mutação de Sentido Incorreto , Ligação Proteica , RNA Replicase/química , RNA Replicase/metabolismo , RNA Viral/biossíntese , Proteínas não Estruturais Virais/química , Proteínas não Estruturais Virais/metabolismo
10.
Int J Toxicol ; 32(5): 336-50, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24097127

RESUMO

Dapagliflozin, a first-in-class, selective inhibitor of sodium-glucose cotransporter 2 (SGLT2), promotes urinary glucose excretion to reduce hyperglycemia for the treatment of type 2 diabetes. A series of nonclinical studies were undertaken to evaluate dapagliflozin in species where it was shown to have pharmacologic activity comparable with that in humans at doses that resulted in supratherapeutic exposures. In vitro screening (>300 targets; 10 µmol/L) indicated no significant off-target activities for dapagliflozin or its primary human metabolite. Once daily, orally administered dapagliflozin was evaluated in Sprague-Dawley rats (≤6 months) and in beagle dogs (≤1 year) at exposures >5000-fold those observed at the maximum recommended human clinical dose (MRHD; 10 mg). Anticipated, pharmacologically mediated effects of glucosuria, osmotic diuresis, and mild electrolyte loss were observed, but there were no adverse effects at clinically relevant exposures, including in the kidneys or urogenital tract. The SGLT2-/- mice, which show chronic glucosuria, and dapagliflozin-treated, wild-type mice exhibited similar safety profiles. In rats but not dogs, dapagliflozin at >2000-fold MRHD exposures resulted in tissue mineralization and trabecular bone accretion. Investigative studies suggested that the effect was not relevant to human safety, since it was partially related to off-target inhibition of SGLT1, which was observed only at high doses of dapagliflozin and resulted in intestinal glucose malabsorption and increased intestinal calcium absorption. The rigorous assessment of supra- and off-target dapagliflozin pharmacology in nonclinical species allowed for a thorough evaluation of potential toxicity, providing us with confidence in its safety in patients with diabetes.


Assuntos
Glucosídeos/toxicidade , Hipoglicemiantes/toxicidade , Inibidores do Transportador 2 de Sódio-Glicose , Animais , Compostos Benzidrílicos , Células CHO , Cricetulus , Cães , Relação Dose-Resposta a Droga , Avaliação Pré-Clínica de Medicamentos , Feminino , Glucosídeos/administração & dosagem , Glucosídeos/farmacocinética , Humanos , Hipoglicemiantes/administração & dosagem , Hipoglicemiantes/farmacocinética , Masculino , Camundongos , Camundongos Endogâmicos ICR , Camundongos Knockout , Ratos , Ratos Sprague-Dawley , Transportador 2 de Glucose-Sódio/genética
11.
J Med Chem ; 56(22): 9275-95, 2013 Nov 27.
Artigo em Inglês | MEDLINE | ID: mdl-24164581

RESUMO

Preclinical antithrombotic efficacy and bleeding models have demonstrated that P2Y1 antagonists are efficacious as antiplatelet agents and may offer a safety advantage over P2Y12 antagonists in terms of reduced bleeding liabilities. In this article, we describe the structural modification of the tert-butyl phenoxy portion of lead compound 1 and the subsequent discovery of a novel series of conformationally constrained ortho-anilino diaryl ureas. In particular, spiropiperidine indoline-substituted diaryl ureas are described as potent, orally bioavailable small-molecule P2Y1 antagonists with improved activity in functional assays and improved oral bioavailability in rats. Homology modeling and rat PK/PD studies on benchmark compound 3l will also be presented. Compound 3l was our first P2Y1 antagonist to demonstrate a robust oral antithrombotic effect with mild bleeding liability in the rat thrombosis and hemostasis models.


Assuntos
Desenho de Fármacos , Conformação Molecular , Compostos de Fenilureia/farmacologia , Compostos de Fenilureia/farmacocinética , Antagonistas do Receptor Purinérgico P2Y/farmacologia , Antagonistas do Receptor Purinérgico P2Y/farmacocinética , Receptores Purinérgicos P2Y1/metabolismo , Compostos de Espiro/farmacologia , Compostos de Espiro/farmacocinética , Ureia/farmacologia , Ureia/farmacocinética , Animais , Disponibilidade Biológica , Humanos , Indóis/química , Modelos Moleculares , Compostos de Fenilureia/química , Compostos de Fenilureia/metabolismo , Antagonistas do Receptor Purinérgico P2Y/química , Antagonistas do Receptor Purinérgico P2Y/metabolismo , Ratos , Ratos Sprague-Dawley , Receptores Purinérgicos P2Y1/química , Homologia de Sequência de Aminoácidos , Compostos de Espiro/química , Compostos de Espiro/metabolismo , Ureia/química , Ureia/metabolismo
12.
J Med Chem ; 56(4): 1704-14, 2013 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-23368907

RESUMO

Two distinct G protein-coupled purinergic receptors, P2Y1 and P2Y12, mediate ADP-driven platelet activation. The clinical effectiveness of P2Y12 blockade is well established. Recent preclinical data suggest that P2Y1 and P2Y12 inhibition provide equivalent antithrombotic efficacy, while targeting P2Y1 has the potential for reduced bleeding liability. In this account, the discovery of a 2-(phenoxypyridine)-3-phenylurea chemotype that inhibited ADP-mediated platelet aggregation in human blood samples is described. Optimization of this series led to the identification of compound 16, 1-(2-(2-tert-butylphenoxy)pyridin-3-yl)-3-4-(trifluoromethoxy)phenylurea, which demonstrated a 68 ± 7% thrombus weight reduction in an established rat arterial thrombosis model (10 mg/kg plus 10 mg/kg/h) while only prolonging cuticle and mesenteric bleeding times by 3.3- and 3.1-fold, respectively, in provoked rat bleeding time models. These results suggest that a P2Y1 antagonist could potentially provide a safe and efficacious antithrombotic profile.


Assuntos
Fibrinolíticos/síntese química , Compostos de Fenilureia/síntese química , Antagonistas do Receptor Purinérgico P2Y/síntese química , Piridinas/síntese química , Ureia/análogos & derivados , Animais , Arteriopatias Oclusivas/sangue , Arteriopatias Oclusivas/tratamento farmacológico , Tempo de Sangramento , Fibrinolíticos/química , Fibrinolíticos/farmacologia , Células HEK293 , Humanos , Masculino , Compostos de Fenilureia/química , Compostos de Fenilureia/farmacologia , Agregação Plaquetária/efeitos dos fármacos , Antagonistas do Receptor Purinérgico P2Y/química , Antagonistas do Receptor Purinérgico P2Y/farmacologia , Piridinas/química , Piridinas/farmacologia , Ratos , Relação Estrutura-Atividade , Trombose/sangue , Trombose/tratamento farmacológico , Ureia/síntese química , Ureia/química , Ureia/farmacologia
13.
J Intensive Care Med ; 27(3): 145-60, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-21525112

RESUMO

Intra-abdominal hypertension (IAH) and abdominal compartment syndrome (ACS) are highly morbid conditions that are common and underrecognized in the intensive care unit. Intra-abdominal hypertension affects the critically ill patient population and is not solely limited to the trauma and surgical subgroups. The recognition of IAH and ACS as distinct clinical states has become more apparent. Extensive bench and clinical research has shed significant light into the definition, incidence, etiology, physiology, clinical manifestations, and treatment strategies. Although further research into this morbid condition is needed, improvement in recognition is a critical first step. This review aims to scrutinize the basic science and clinical literature available on this condition in a surgically focused, organ-system-based approach.


Assuntos
Cuidados Críticos/métodos , Hipertensão Intra-Abdominal , Músculos Abdominais/irrigação sanguínea , Técnicas de Fechamento de Ferimentos Abdominais , Lesão Renal Aguda , Humanos , Hipertensão Intra-Abdominal/complicações , Hipertensão Intra-Abdominal/diagnóstico , Hipertensão Intra-Abdominal/fisiopatologia , Complicações Pós-Operatórias , Resultado do Tratamento
14.
J Pharmacol Exp Ther ; 339(2): 589-96, 2011 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-21828263

RESUMO

The thienopyridine antiplatelet drugs, such as ticlopidine, clopidogrel, and prasugrel, require activation by cytochromes P450 in vivo to effectively block platelet aggregation. The study of the metabolic activation of these compounds has been hampered by the lability and reactivity of the ring-opened active metabolite (AM) and by the numerous metabolites that can be formed in such a transformation. We have developed a novel method whereby platelets are incubated with the cytochrome P450 and the thienopyridine of interest for various amounts of time, and the effects on ADP-driven platelet aggregation are directly examined. In this way, the platelet is used as a biosensor for detection of the AM. Using this method, cytochromes P450 capable of converting clopidogrel, prasugrel, and 2-oxo-clopidogrel to metabolites that inhibit ADP-induced platelet aggregation were identified as well as which cytochromes P450 were capable of catalyzing partial reactions (e.g., conversion of 2-oxo-clopidogrel to the AM). These studies show that, in vitro, CYP3A4/5, 2C19, and 2B6 are individually capable of converting clopidogrel and prasugrel to the AM and that the cytochrome P450 preference for these two thienopyridines is very similar.


Assuntos
Plaquetas/efeitos dos fármacos , Sistema Enzimático do Citocromo P-450/metabolismo , Piperazinas/farmacologia , Inibidores da Agregação de Plaquetas/farmacologia , Agregação Plaquetária/efeitos dos fármacos , Tienopiridinas/metabolismo , Tiofenos/farmacologia , Hidrocarboneto de Aril Hidroxilases/metabolismo , Baculoviridae , Técnicas Biossensoriais , Biotransformação , Plaquetas/metabolismo , Clopidogrel , Citocromo P-450 CYP2B6 , Citocromo P-450 CYP2C19 , Citocromo P-450 CYP3A/metabolismo , Ensaios Enzimáticos , Humanos , Microssomos , Piperazinas/metabolismo , Inibidores da Agregação de Plaquetas/metabolismo , Plasma Rico em Plaquetas/metabolismo , Cloridrato de Prasugrel , Tienopiridinas/farmacologia , Tiofenos/metabolismo , Ticlopidina/análogos & derivados , Ticlopidina/metabolismo , Ticlopidina/farmacologia
15.
J Intensive Care Med ; 23(2): 122-7, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18431828

RESUMO

Anion gap, anion gap corrected for serum albumin, and base deficit are often used as surrogates for measuring serum lactate. None of these surrogates is postulated to predict hyperlactatemia in the critically ill. We prospectively collected data from September 2004 through August 2005 for 1381 consecutive admissions. Patients with renal disease, ketoacidosis, or toxic ingestion were excluded. Anion gap, anion gap corrected for albumin, and base deficit were calculated for all patients. We identified 286 patients who met our inclusion or exclusion criteria. The receiver-operating characteristic area under the curve for the prediction of hyperlactatemia for anion gap, anion gap corrected for albumin, and base deficit were 0.55, 0.57, and 0.64, respectively. Anion gap, anion gap corrected for albumin, and base deficit do not predict the presence or absence of clinically significant hyperlactatemia. Serum lactate should be measured in all critically ill adults in whom hypoperfusion is suspected.


Assuntos
Acidose Láctica/sangue , Acidose Láctica/diagnóstico , Análise Química do Sangue/métodos , Choque/diagnóstico , Equilíbrio Ácido-Base , Feminino , Humanos , Hipoalbuminemia/sangue , Masculino , Pessoa de Meia-Idade , Curva ROC , Estudos Retrospectivos , Sensibilidade e Especificidade
16.
Anal Biochem ; 357(2): 216-24, 2006 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-16889745

RESUMO

Calcium signaling in platelets is an important physiological response to various aggregation stimuli. Loading platelets with various fluorescent dyes and measuring the change in calcium concentration using a spectrofluorometer has been the traditional approach to studying calcium signaling. This method suffers from the need for large platelet samples and a decrease in total fluorescence signal with time due to photobleaching. Therefore, it is rarely used to measure the quantitative effect of an agonist or antagonist on calcium signaling. Adaptation of these measurements to a fluorescent imaging plate reader (FLIPR) format allows the sample size to be reduced by 5- to 10-fold, and the microplate format allows a significant increase in throughput. Addition of the agonists to all wells simultaneously serves to normalize the total response. This article describes the first use of a FLIPR to study the calcium flux in human platelets. The IC(50) values showed a linear correlation with the K(i) for receptor binding in washed platelets. The generality of the methodology was shown by measuring EC(50) values for agonists and IC(50) values for antagonists of the platelet G protein-coupled receptor P2Y(1) and for the ion channel P2X(1).


Assuntos
Plaquetas/metabolismo , Sinalização do Cálcio , Cálcio/análise , Cálcio/sangue , Corantes Fluorescentes/análise , Dimetil Sulfóxido , Humanos , Concentração Inibidora 50 , Modelos Moleculares , Receptores Acoplados a Proteínas-G/metabolismo
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