RESUMO
A duplexed, functional multiaddition high throughput screen and subsequent iterative parallel synthesis effort identified the first highly selective and CNS penetrant glucagon-like peptide-1R (GLP-1R) positive allosteric modulator (PAM). PAM (S)-9b potentiated low-dose exenatide to augment insulin secretion in primary mouse pancreatic islets, and (S)-9b alone was effective in potentiating endogenous GLP-1R to reverse haloperidol-induced catalepsy.
Assuntos
Indóis/síntese química , Pirrolidinas/síntese química , Receptores de Glucagon/efeitos dos fármacos , Regulação Alostérica/efeitos dos fármacos , Animais , Catalepsia/induzido quimicamente , Catalepsia/tratamento farmacológico , Fármacos do Sistema Nervoso Central/uso terapêutico , Sinergismo Farmacológico , Exenatida , Peptídeo 1 Semelhante ao Glucagon/farmacologia , Receptor do Peptídeo Semelhante ao Glucagon 1 , Haloperidol , Ensaios de Triagem em Larga Escala , Indóis/metabolismo , Indóis/farmacocinética , Indóis/farmacologia , Insulina/metabolismo , Secreção de Insulina , Ilhotas Pancreáticas/efeitos dos fármacos , Masculino , Camundongos Endogâmicos C57BL , Microssomos Hepáticos/metabolismo , Peptídeos/farmacologia , Pirrolidinas/metabolismo , Pirrolidinas/farmacocinética , Pirrolidinas/farmacologia , Relação Estrutura-Atividade , Peçonhas/farmacologiaRESUMO
Injectable, degradation-resistant peptide agonists for the glucagon-like peptide 1 (GLP-1) receptor (GLP-1R), such as exenatide and liraglutide, activate the GLP-1R via a complex orthosteric-binding site and are effective therapeutics for glycemic control in type 2 diabetes. Orally bioavailable orthosteric small-molecule agonists are unlikely to be developed, whereas positive allosteric modulators (PAMs) may offer an improved therapeutic profile. We hypothesize that allosteric modulators of the GLP-1R would increase the potency and efficacy of native GLP-1 in a spatial and temporally preserved manner and/or may improve efficacy or side effects of injectable analogs. We report the design, optimization, and initial results of a duplexed high-throughput screen in which cell lines overexpressing either the GLP-1R or the glucagon receptor were coplated, loaded with a calcium-sensitive dye, and probed in a three-phase assay to identify agonists, antagonists, and potentiators of GLP-1, and potentiators of glucagon. 175,000 compounds were initially screened, and progression through secondary assays yielded 98 compounds with a variety of activities at the GLP-1R. Here, we describe five compounds possessing different patterns of modulation of the GLP-1R. These data uncover PAMs that may offer a drug-development pathway to enhancing in vivo efficacy of both endogenous GLP-1 and peptide analogs.
Assuntos
Peptídeo 1 Semelhante ao Glucagon/química , Ensaios de Triagem em Larga Escala/métodos , Receptores de Glucagon/química , Regulação Alostérica/efeitos dos fármacos , Sítio Alostérico , Animais , Sítios de Ligação , Células CHO , Cálcio/química , Linhagem Celular , Linhagem Celular Tumoral , Cricetinae , Cricetulus , AMP Cíclico/química , Progressão da Doença , Exenatida , Glucose/química , Humanos , Liraglutida/química , Peptídeos/química , Proteínas Recombinantes/química , Transdução de Sinais , Peçonhas/químicaRESUMO
We have examined the impact of the inflammatory cytokines interleukin-1 beta (IL-1beta) and tumor necrosis factor alpha (TNFalpha) on assembly of nAChRs from subunit mixtures of nAChRalpha4, beta2 and beta4 transiently transfected into 293 cells. In control transfections approximately 55% of alpha4 associated preferentially with beta4, but less than 15% complexed with beta2 and the remainder was associated with both beta subunits. These relative ratios were modified by pro-inflammatory cytokines. IL-1beta strongly enhanced alpha4/beta2 association and decreased alpha4/beta4, whereas TNFalpha promoted mixed alpha4/beta2/beta4 interactions. These results show that the emerging rules governing assembly of nAChRs are subject to modification by the pro-inflammatory cytokine environment.