RESUMO
While anti-angiogenic therapies for wet age-related macular degeneration (AMD) are effective for many patients, they require multiple injections and are expensive and prone to complications. Gene therapy could be an elegant solution for this problem by providing a long-term source of anti-angiogenic proteins after a single administration. Another potential issue with current therapeutic proteins containing a fragment crystallizable (Fc) domain (such as whole antibodies like bevacizumab) is the induction of an unwanted immune response. In wet AMD, a low level of inflammation is already present, so to avoid exacerbation of disease by the therapeutic protein, we propose single-chain fragment variable (scFv) antibodies, which lack the Fc domain, as a safer alternative. To investigate the feasibility of this, anti-vascular endothelial growth factor (VEGF)-blocking antibodies in two formats were produced and tested in vitro and in vivo. The scFv transgene was then cloned into an adeno-associated virus (AAV) vector. A therapeutic effect in a mouse model of choroidal neovascularization (CNV) was demonstrated with antibodies in both scFv and immunoglobulin G1 (IgG1) formats (p < 0.04). Importantly, the scFv anti-VEGF antibody expressed from an AAV vector also had a significant beneficial effect (p = 0.02), providing valuable preclinical data for future translation to the clinic.
RESUMO
A novel series of pyrrolidine-containing GPR40 agonists is described as a potential treatment for type 2 diabetes. The initial pyrrolidine hit was modified by moving the position of the carboxylic acid, a key pharmacophore for GPR40. Addition of a 4-cis-CF3 to the pyrrolidine improves the human GPR40 binding Ki and agonist efficacy. After further optimization, the discovery of a minor enantiomeric impurity with agonist activity led to the finding that enantiomers (R,R)-68 and (S,S)-68 have differential effects on the radioligand used for the binding assay, with (R,R)-68 potentiating the radioligand and (S,S)-68 displacing the radioligand. Compound (R,R)-68 activates both Gq-coupled intracellular Ca2+ flux and Gs-coupled cAMP accumulation. This signaling bias results in a dual mechanism of action for compound (R,R)-68, demonstrating glucose-dependent insulin and GLP-1 secretion in vitro. In vivo, compound (R,R)-68 significantly lowers plasma glucose levels in mice during an oral glucose challenge, encouraging further development of the series.
Assuntos
Hipoglicemiantes/farmacologia , Pirrolidinas/farmacologia , Receptores Acoplados a Proteínas G/agonistas , Animais , Glicemia/análise , Glicemia/metabolismo , Linhagem Celular , Células Cultivadas , Diabetes Mellitus Tipo 2/sangue , Diabetes Mellitus Tipo 2/tratamento farmacológico , Diabetes Mellitus Tipo 2/metabolismo , Peptídeo 1 Semelhante ao Glucagon/metabolismo , Humanos , Hipoglicemiantes/química , Hipoglicemiantes/farmacocinética , Hipoglicemiantes/uso terapêutico , Insulina/metabolismo , Masculino , Camundongos Endogâmicos C57BL , Modelos Moleculares , Pirrolidinas/química , Pirrolidinas/farmacocinética , Pirrolidinas/uso terapêutico , Ratos , Receptores Acoplados a Proteínas G/metabolismoRESUMO
The potent MCHR1 in vitro and in vivo antagonist activity of a series of cyclic tertiary alcohols derived from compound 2b is described. Subsequent pharmacokinetic and pharmacodynamic studies identified BMS-814580 (compound 10) as a highly efficacious antiobesity agent with a relatively clean in vitro and in vivo safety profile.
Assuntos
Fármacos Antiobesidade/química , Fármacos Antiobesidade/uso terapêutico , Obesidade/tratamento farmacológico , Pirimidinas/química , Pirimidinas/uso terapêutico , Receptores de Somatostatina/antagonistas & inibidores , Animais , Fármacos Antiobesidade/farmacocinética , Fármacos Antiobesidade/farmacologia , Cães , Halogenação , Humanos , Macaca fascicularis , Masculino , Camundongos , Pirimidinas/farmacocinética , Pirimidinas/farmacologia , Ratos , Receptores de Somatostatina/metabolismo , Relação Estrutura-AtividadeRESUMO
Intimate partner violence (IPV) is prevalent in Kenya, yet few studies have examined the role of health care providers (HCPs) in addressing IPV. Interviews with 18 Kenyan HCPs explored how they recognize and support IPV victims, including barriers to care. HCPs most commonly see victims of physical abuse. Medical responses to victims included counseling, treatment, and referrals, although rural HCPs reported fewer available services than in urban settings. HCPs attributed the limited response to IPV victims to unclear laws and fragmented care, especially in a culture where IPV remains largely unspoken and underreported. These results underscore the need for increased training on IPV assessment and response for HCPs in Kenya, with emphasis on standardized care guidelines for victims.
Assuntos
Atitude do Pessoal de Saúde , Vítimas de Crime/estatística & dados numéricos , Pessoal de Saúde/psicologia , Violência por Parceiro Íntimo/prevenção & controle , Relações Médico-Paciente , Adulto , Serviços de Saúde Comunitária/organização & administração , Feminino , Humanos , Violência por Parceiro Íntimo/estatística & dados numéricos , Quênia , Masculino , Pessoa de Meia-IdadeRESUMO
Non-basic azolotriazinones were explored using an empirical free brain exposures-driven approach to identify potent MCHR1 antagonists for evaluation in in vivo efficacy studies. An optimized lead from this series, 1j (rMCHR1 Ki=1.8 nM), demonstrated a 6.9% reduction in weight gain relative to vehicle in a rat model at 30 mg/kg after 4 days of once-daily oral treatment as a glycine prodrug. Despite a promising efficacy profile, an assessment of the biliary toxicity risk of this compound rendered this compound non-progressible.
Assuntos
Encéfalo/efeitos dos fármacos , Obesidade/tratamento farmacológico , Receptores de Somatostatina/antagonistas & inibidores , Triazinas/farmacologia , Animais , Encéfalo/metabolismo , Relação Dose-Resposta a Droga , Humanos , Estrutura Molecular , Obesidade/metabolismo , Ratos , Relação Estrutura-Atividade , Triazinas/administração & dosagem , Triazinas/químicaRESUMO
Our investigation of the structure-activity and structure-liability relationships for dihydropyrrolopyrazol-6-one MCHR1 antagonists revealed that off-rate characteristics, inferred from potencies in a FLIPR assay following a 2 h incubation, can impact in vivo efficacy. The in vitro and exposure profiles of dihydropyrrolopyrazol-6-ones 1b and 1e were comparable to that of the thienopyrimidinone counterparts 41 and 43 except for a much faster MCHR1 apparent off-rate. The greatly diminished dihydropyrrolopyrazol-6-one anti-obesity response may be the consequence of this rapid off-rate.
Assuntos
Fármacos Antiobesidade/química , Pirazóis/química , Receptores de Somatostatina/antagonistas & inibidores , Animais , Fármacos Antiobesidade/farmacocinética , Fármacos Antiobesidade/farmacologia , Fármacos Antiobesidade/uso terapêutico , Meia-Vida , Humanos , Obesidade/tratamento farmacológico , Ligação Proteica , Pirazóis/farmacocinética , Pirazóis/farmacologia , Pirazóis/uso terapêutico , Ratos , Ratos Sprague-Dawley , Receptores de Somatostatina/metabolismo , Relação Estrutura-Atividade , Redução de Peso/efeitos dos fármacosRESUMO
The design, synthesis and structure-activity relationships of a novel series of 3,4-disubstituted pyrrolidine acid analogs as PPAR ligands is outlined. In both the 1,3- and 1,4-oxybenzyl pyrrolidine acid series, the preferred stereochemistry was shown to be the cis-3R,4S isomer, as exemplified by the potent dual PPARα/γ agonists 3k and 4i. The N-4-trifluoromethyl-pyrimidinyl pyrrolidine acid analog 4i was efficacious in lowering fasting glucose and triglyceride levels in diabetic db/db mice.
Assuntos
Hipoglicemiantes/síntese química , PPAR alfa/agonistas , PPAR gama/agonistas , Pirrolidinas/química , Animais , Glicemia/análise , Diabetes Mellitus Tipo 2/tratamento farmacológico , Desenho de Fármacos , Feminino , Hipoglicemiantes/química , Hipoglicemiantes/uso terapêutico , Ligantes , Camundongos , Camundongos Obesos , PPAR alfa/metabolismo , PPAR gama/metabolismo , Pirrolidinas/síntese química , Pirrolidinas/uso terapêutico , Estereoisomerismo , Relação Estrutura-Atividade , Triglicerídeos/sangueRESUMO
Identification of MCHR1 antagonists with a preclinical safety profile to support clinical evaluation as antiobesity agents has been a challenge. Our finding that a basic moiety is not required for MCHR1 antagonists to achieve high affinity allowed us to explore structures less prone to off-target activities such as hERG inhibition. We report the SAR evolution of hydroxylated thienopyrimidinone ethers culminating in the identification of 27 (BMS-819881), which entered obesity clinical trials as the phosphate ester prodrug 35 (BMS-830216).
Assuntos
Fármacos Antiobesidade/farmacologia , Descoberta de Drogas , Obesidade/tratamento farmacológico , Receptores de Somatostatina/antagonistas & inibidores , Animais , Fármacos Antiobesidade/farmacocinética , Fármacos Antiobesidade/uso terapêutico , Cães , Canal de Potássio ERG1 , Canais de Potássio Éter-A-Go-Go/antagonistas & inibidores , Humanos , Masculino , RatosRESUMO
OBJECTIVES: To examine the impact of serum-derived bovine immunoglobulin, an oral medical food known to neutralize bacterial antigen and reduce intestinal inflammation, on restoration of mucosal immunity and gastrointestinal function in individuals with HIV enteropathy. DESIGN: Open-label trial with intensive 8-week phase of bovine serum immunoglobulin (SBI) 2.5âg twice daily with a 4-week washout period and an optional 9-month extension study. METHODS: HIV enteropathy was defined as chronic gastrointestinal symptoms including frequent loose or watery stools despite no identifiable, reversible cause. Upper endoscopy for tissue immunofluorescent antibody assay and disaccharide gut permeability/absorption studies were performed before and after 8 weeks of SBI to test mucosal immunity and gastrointestinal function. Blood was collected for markers of microbial translocation, inflammation, and collagen kinetics. A validated gastrointestinal questionnaire assessed changes in symptoms. RESULTS: All eight participants experienced profound improvement in symptoms with reduced bowel movements/day (Pâ=â0.008) and improvements in stool consistency (Pâ=â0.008). Gut permeability was normal before and after the intervention, but D-xylose absorption increased in seven of eight participants. Mucosal CD4 lymphocyte densities increased by a median of 139.5âcells/mm2 from 213 to 322âcells/mm2 (Pâ=â0.016). Intestinal-fatty acid binding protein (I-FABP), a marker of enterocyte damage, initially rose in seven of eight participants after 8 weeks (Pâ=â0.039), and then fell below baseline in four of five who continued receiving SBI (Pâ=â0.12). Baseline serum I-FABP levels were negatively correlated with subsequent rise in mucosal CD4 lymphocyte densities (râ=â-0.74, Pâ=â0.046). CONCLUSION: SBI significantly increases intestinal mucosal CD4 lymphocyte counts, improves duodenal function, and showed evidence of promoting intestinal repair in the setting of HIV enteropathy.
Assuntos
Adsorção , Dieta/métodos , Duodeno/imunologia , Enteropatia por HIV/terapia , Imunidade nas Mucosas , Imunoglobulinas/administração & dosagem , Soroglobulinas/administração & dosagem , Administração Oral , Adulto , Animais , Contagem de Linfócito CD4 , Bovinos , Duodeno/patologia , Duodeno/fisiopatologia , Enteropatia por HIV/imunologia , Humanos , Imunoglobulinas/isolamento & purificação , Masculino , Projetos Piloto , Soroglobulinas/isolamento & purificação , Resultado do TratamentoRESUMO
The insect baculovirus AcMNPV (Autographa californica multiple nuclear polyhedrosis virus) enters many mammalian cell lines, prompting its application as a general eukaryotic gene delivery agent, but the basis of entry is poorly understood. For adherent mammalian cells, we show that entry is favoured by low pH and by increasing the available cell-surface area through a transient release from the substratum. Low pH also stimulated baculovirus entry into mammalian cells grown in suspension which, optimally, could reach 90% of the transduced population. The basic loop, residues 268-281, of the viral surface glycoprotein gp64 was required for entry and a tetra mutant with increasing basicity increased entry into a range of mammalian cells. The same mutant failed to plaque in Sf9 cells, instead showing individual cell entry and minimal cell-to-cell spread, consistent with an altered fusion phenotype. Viruses grown in different insect cells showed different mammalian cell entry efficiencies, suggesting that additional factors also govern entry.
Assuntos
Nucleopoliedrovírus/metabolismo , Proteínas Virais de Fusão/metabolismo , Internalização do Vírus , Animais , Células CHO , Membrana Celular/metabolismo , Membrana Celular/virologia , Cricetinae , Cricetulus , Genes Reporter , Vetores Genéticos/genética , Vetores Genéticos/metabolismo , Proteínas de Fluorescência Verde/genética , Proteínas de Fluorescência Verde/metabolismo , Células HEK293 , Humanos , Concentração de Íons de Hidrogênio , Mutagênese , Nucleopoliedrovírus/genética , Regiões Promotoras Genéticas , Células Sf9 , Transformação Genética , Proteínas Virais de Fusão/genética , Ensaio de Placa Viral , Ligação ViralRESUMO
This study funded by Centers for Disease Control compares HIV prevalence and risk behavior among heterosexual methamphetamine (n = 428) and nonmethamphetamine (n = 878) injectors in California, USA, during 2001-2003. While HIV was not highly prevalent among methamphetamine injectors (3%), sexual and injection risk behaviors were highly prevalent (ranging from 21% to 72%). In multivariate analyses, methamphetamine injectors had higher odds than nonmethamphetamine injectors of unprotected vaginal intercourse and sex with five or more sexual partners in the past 6 months and of distributive and receptive syringe sharing in the past 30 days. There was no significant difference in HIV sero-status by methamphetamine use. Suggestions are made for designing HIV prevention programs. The study's limitations are noted.
Assuntos
Infecções por HIV/epidemiologia , Heterossexualidade , Metanfetamina , Abuso de Substâncias por Via Intravenosa , Adulto , California/epidemiologia , Feminino , Infecções por HIV/etiologia , Soropositividade para HIV/diagnóstico , Soropositividade para HIV/epidemiologia , Humanos , Entrevistas como Assunto , Masculino , Pessoa de Meia-Idade , Fatores de Risco , Comportamento Sexual/estatística & dados numéricos , Sexo sem Proteção/estatística & dados numéricosRESUMO
Latinos in the United States are an ethnically diverse group disproportionately affected by HIV/AIDS. We describe HIV seroprevalence, HIV risk behaviors and utilization of health services among Mexican American injection drug users (IDUs) in California (n = 286) and compare them to White (n = 830) and African American (n = 314) IDUs. Study participants were recruited from syringe exchange programs (n = 24) in California. HIV seroprevalence among Mexican Americans (0.5%) was dramatically lower than Whites (5%) and African Americans (8%). Mexican Americans reported fewer sex-related risks than Whites and African Americans though injection-related risks remained high. Compared to Whites, Mexican Americans were more likely to participate in drug treatment during a 6 month period (AOR 1.5, 95% CI 1.1, 2.0) but less likely to receive any health care (AOR 0.6, 95% CI 0.5, 0.8). Exploring cultural and structural factors among Mexican American IDUs may offer new insights into how to maintain low rates of HIV seroprevalence and reduce barriers to health care utilization.
Assuntos
Infecções por HIV/epidemiologia , Americanos Mexicanos/estatística & dados numéricos , Abuso de Substâncias por Via Intravenosa/epidemiologia , Adulto , California/epidemiologia , Usuários de Drogas/estatística & dados numéricos , Feminino , Infecções por HIV/complicações , Infecções por HIV/etnologia , Humanos , Masculino , Pessoa de Meia-Idade , Uso Comum de Agulhas e Seringas , Programas de Troca de Agulhas/estatística & dados numéricos , Assunção de Riscos , Estudos Soroepidemiológicos , Comportamento Sexual/etnologia , Comportamento Sexual/estatística & dados numéricos , Fatores Socioeconômicos , Abuso de Substâncias por Via Intravenosa/complicações , Abuso de Substâncias por Via Intravenosa/etnologiaRESUMO
The orexigenic peptide ghrelin has been shown to have prokinetic activity in the gastrointestinal (GI) system of several species, including humans. In this series of experiments, we have evaluated the prokinetic activity of novel, small-molecule ghrelin receptor (GhrR) agonists after parenteral and peroral dosing in mice and rats. Gastric emptying, small intestinal transport, and fecal output were determined after intraperitoneal and intracerebroventricular dosing of GhrR agonists, using ghrelin as a positive control. These same parameters were evaluated after oral gavage dosing of the synthetic agonists. Regardless of dose route, GhrR agonist treatment increased gastric emptying, small intestinal transit, and fecal output. However, fecal output was only increased by GhrR agonist treatment if mice were able to feed during the stimulatory period. Thus, GhrR agonists can stimulate upper GI motility, and the orexigenic action of the compounds can indirectly contribute to prokinetic activity along the entire GI tract. The orexigenic and prokinetic effects of either ghrelin or small-molecule GhrR agonists were selective for the GhrR because they were absent when evaluated in GhrR knockout mice. We next evaluated the efficacy of the synthetic GhrR agonists dosed in a model of opiate-induced bowel dysfunction induced by a single injection of morphine. Oral dosing of a GhrR agonist normalized GI motility in opiate-induced dysmotility. These data demonstrate the potential utility of GhrR agonists for treating gastrointestinal hypomotility disorders.
Assuntos
Motilidade Gastrointestinal/efeitos dos fármacos , Grelina/administração & dosagem , Grelina/farmacologia , Hormônios Peptídicos/administração & dosagem , Hormônios Peptídicos/farmacologia , Receptores de Grelina/agonistas , Administração Oral , Animais , Peso Corporal/efeitos dos fármacos , Doença de Bowen/induzido quimicamente , Doença de Bowen/tratamento farmacológico , Doença de Bowen/fisiopatologia , Sistema Nervoso Central/efeitos dos fármacos , Defecação/efeitos dos fármacos , Ingestão de Alimentos/efeitos dos fármacos , Esvaziamento Gástrico/efeitos dos fármacos , Trânsito Gastrointestinal/efeitos dos fármacos , Intestino Delgado/efeitos dos fármacos , Intestino Delgado/fisiologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Morfina/farmacologia , Hormônios Peptídicos/sangue , Ratos , Ratos Sprague-Dawley , Receptores de Grelina/genética , Receptores de Grelina/metabolismoRESUMO
The design, synthesis and structure-activity relationships of a novel series of N-phenyl-substituted pyrrole, 1,2-pyrazole and 1,2,3-triazole acid analogs as PPAR ligands are outlined. The triazole acid analogs 3f and 4f were identified as potent dual PPARalpha/gamma agonists both in binding and functional assays in vitro. The 3-oxybenzyl triazole acetic acid analog 3f showed excellent glucose and triglyceride lowering in diabetic db/db mice.
Assuntos
Azóis/síntese química , Desenho de Fármacos , PPAR alfa/agonistas , PPAR gama/agonistas , Animais , Azóis/farmacologia , Linhagem Celular/enzimologia , Cristalografia por Raios X , Feminino , Humanos , Concentração de Íons de Hidrogênio , Camundongos , Camundongos Transgênicos , PPAR alfa/metabolismo , PPAR gama/metabolismo , Relação Estrutura-AtividadeRESUMO
The discovery and optimization of a novel series of prolinol-derived GHSR agonists is described. This series emerged from a 11,520-member solid-phase library targeting the GPCR protein superfamily, and the rapid optimization of low micromolar hits into single-digit nanomolar leads can be attributed to the solid-phase synthesis of matrix libraries, which revealed multiple non-additive structure-activity relationships. In addition, the separation of potent diastereomers highlighted the influence of the alpha-methyl stereochemistry of the phenoxyacetamide sidechain on GHSR activity.
Assuntos
Pirrolidinas/síntese química , Pirrolidinas/farmacologia , Receptores Acoplados a Proteínas G/efeitos dos fármacos , Receptores de Grelina/agonistas , Técnicas de Química Combinatória , Estrutura Molecular , Pirrolidinas/química , Estereoisomerismo , Relação Estrutura-AtividadeRESUMO
The first enantioselective synthesis of (D)-2-tert-butoxycarbonylamino-5,5-difluoro-5-phenyl-pentanoic acid 3 was achieved. The incorporation of the titled compound into growth hormone secretagogue (GHS) compounds resulted in new analogs 10 and 16, both of which had significantly increased in vitro potency. The compound 10 also showed improved in vivo efficacy as well as pharmacokinetic properties in rat models.
Assuntos
Hormônio do Crescimento/metabolismo , Ácidos Pentanoicos/síntese química , Administração Oral , Animais , Área Sob a Curva , Disponibilidade Biológica , Carbamatos/farmacologia , Química Farmacêutica/métodos , Desenho de Fármacos , Indóis/farmacologia , Modelos Químicos , Ácidos Pentanoicos/química , Ácidos Pentanoicos/farmacologia , Hormônios Peptídicos/química , Ratos , Compostos de Espiro/farmacologia , Estereoisomerismo , Tetrazóis/farmacologiaRESUMO
Several series of substituted dehydropiperidine and piperidine-4-carboxylic acid analogs have been designed and synthesized as novel, potent dual PPARalpha/gamma agonists. The SAR of these series of analogs is discussed. A rare double bond migration occurred during the basic hydrolysis of the alpha,beta-unsaturated dehydropiperidine esters 12, and the structures of the migration products were confirmed through a series of 2D NMR experiments.
Assuntos
Ácidos Carboxílicos , PPAR alfa/agonistas , PPAR gama/agonistas , Piperidinas , Ligação Competitiva/efeitos dos fármacos , Ácidos Carboxílicos/síntese química , Ácidos Carboxílicos/química , Ácidos Carboxílicos/farmacologia , Relação Dose-Resposta a Droga , Desenho de Fármacos , Humanos , Concentração Inibidora 50 , Estrutura Molecular , Piperidinas/síntese química , Piperidinas/química , Piperidinas/farmacologia , Estereoisomerismo , Relação Estrutura-AtividadeRESUMO
A novel series of N1 substituted tetrazole amides were prepared and showed to be potent growth hormone (GH) secretagogues. Among them, hydroxyl containing analog 31 displayed excellent in vivo activity by increasing plasma GH 10-fold in an anesthetized IV rat model.
Assuntos
Amidas/síntese química , Amidas/farmacologia , Hormônio do Crescimento/metabolismo , Tetrazóis/química , Amidas/química , Animais , Linhagem Celular , Glioma/metabolismo , Hormônio do Crescimento/sangue , Estrutura Molecular , Ratos , Relação Estrutura-AtividadeAssuntos
Infecção Hospitalar/microbiologia , Resistência a Meticilina , Infecções Estafilocócicas/microbiologia , Staphylococcus aureus/efeitos dos fármacos , Infecção Hospitalar/epidemiologia , Farmacorresistência Bacteriana , Humanos , Infecções Estafilocócicas/epidemiologia , Infecções Estafilocócicas/prevenção & controle , Infecções Estafilocócicas/transmissão , Staphylococcus aureus/classificação , Staphylococcus aureus/enzimologiaRESUMO
1H-tetrazole-1-alkanenitrile SR-9g exhibits a >10-fold in vivo potency enhancement over the lead nitrile 1 and has acceptable oral bioavailability in rats and dogs. An enantiospecific synthesis of 1H-tetrazole-1-alkanenitrile nitriles 9 has been developed.