RESUMO
The mammalian mitochondrial branched-chain ketoacid dehydrogenase (BCKD) complex is a multienzyme complex involved in the catabolism of branched-chain amino acids. BCKD is regulated by the BCKD kinase, or BCKDK, which binds to the E2 subunit of BCKD, phosphorylates its E1 subunit, and inhibits enzymatic activity. Inhibition of the BCKD complex results in increased levels of branched-chain amino acids and branched-chain ketoacids, and this buildup has been associated with heart failure, type 2 diabetes mellitus, and nonalcoholic fatty liver disease. To find BCKDK inhibitors for potential treatment of these diseases, we performed both NMR and virtual fragment screening and identified tetrazole-bearing fragments that bind BCKDK at multiple sites. Through structure-based virtual screening expanding from these fragments, the angiotensin receptor blocker class antihypertension drugs and angiotensin receptor blocker-like compounds were discovered to be potent BCKDK inhibitors, suggesting potential new avenues for heart failure treatment combining BCKDK inhibition and antihypertension.
Assuntos
3-Metil-2-Oxobutanoato Desidrogenase (Lipoamida) , Antagonistas de Receptores de Angiotensina , Humanos , 3-Metil-2-Oxobutanoato Desidrogenase (Lipoamida)/metabolismo , Aminoácidos de Cadeia Ramificada/metabolismo , Antagonistas de Receptores de Angiotensina/farmacologia , Complexos Multienzimáticos/metabolismo , Insuficiência Cardíaca , HipertensãoRESUMO
The optimization for selectivity and central receptor occupancy for a series of spirocyclic azetidine-piperidine inverse agonists of the ghrelin receptor is described. Decreased mAChR muscarinic M2 binding was achieved by use of a chiral indane in place of a substituted benzylic group. Compounds with desirable balance of human in vitro clearance and ex vivo central receptor occupancy were discovered by incorporation of heterocycles. Specifically, heteroaryl rings with nitrogen(s) vicinal to the indane linkage provided the most attractive overall properties.
Assuntos
Sistema Nervoso Central/efeitos dos fármacos , Receptores de Grelina/antagonistas & inibidores , Sequência de Aminoácidos , Animais , Sítios de Ligação , Agonismo Inverso de Drogas , Compostos Heterocíclicos/química , Compostos Heterocíclicos/farmacologia , Humanos , Indanos/química , Indanos/farmacologia , Concentração Inibidora 50 , Isomerismo , Estrutura Molecular , Ligação Proteica/efeitos dos fármacos , Ratos , Relação Estrutura-AtividadeRESUMO
Branched chain amino acid (BCAA) catabolic impairments have been implicated in several diseases. Branched chain ketoacid dehydrogenase (BCKDH) controls the rate limiting step in BCAA degradation, the activity of which is inhibited by BCKDH kinase (BDK)-mediated phosphorylation. Screening efforts to discover BDK inhibitors led to identification of thiophene PF-07208254, which improved cardiometabolic endpoints in mice. Structure-activity relationship studies led to identification of a thiazole series of BDK inhibitors; however, these inhibitors did not improve metabolism in mice upon chronic administration. While the thiophenes demonstrated sustained branched chain ketoacid (BCKA) lowering and reduced BDK protein levels, the thiazoles increased BCKAs and BDK protein levels. Thiazoles increased BDK proximity to BCKDH-E2, whereas thiophenes reduced BDK proximity to BCKDH-E2, which may promote BDK degradation. Thus, we describe two BDK inhibitor series that possess differing attributes regarding BDK degradation or stabilization and provide a mechanistic understanding of the desirable features of an effective BDK inhibitor.
Assuntos
Aminoácidos de Cadeia Ramificada , Tiofenos , Camundongos , Animais , Aminoácidos de Cadeia Ramificada/metabolismo , Fosforilação , Tiofenos/farmacologia , Oxirredutases/metabolismoRESUMO
Previous drug discovery efforts identified classical PYK2 kinase inhibitors such as 2 and 3 that possess selectivity for PYK2 over its intra-family isoform FAK. Efforts to identify more kinome-selective chemical matter that stabilize a DFG-out conformation of the enzyme are described herein. Two sub-series of PYK2 inhibitors, an indole carboxamide-urea and a pyrazole-urea have been identified and found to have different binding interactions with the hinge region of PYK2. These leads proved to be more selective than the original classical inhibitors.
Assuntos
Quinase 2 de Adesão Focal/antagonistas & inibidores , Indóis/farmacologia , Inibidores de Proteínas Quinases/farmacologia , Pirazóis/farmacologia , Ureia/farmacologia , Animais , Cristalografia por Raios X , Relação Dose-Resposta a Droga , Quinase 2 de Adesão Focal/metabolismo , Células HEK293 , Humanos , Indóis/síntese química , Indóis/química , Modelos Moleculares , Estrutura Molecular , Inibidores de Proteínas Quinases/síntese química , Inibidores de Proteínas Quinases/química , Pirazóis/síntese química , Pirazóis/química , Ratos , Relação Estrutura-Atividade , Ureia/análogos & derivados , Ureia/químicaRESUMO
This work addresses the link between selectivity and an unusual, folded conformation for the P-loop observed initially for MAP4K4 and subsequently for other kinases. Statistical and computational analyses of our crystal structure database demonstrate that inhibitors that induce the P-loop folded conformation tend to be more selective, especially if they take advantage of this specific conformation by interacting more favorably with a conserved Tyr or Phe residue from the P-loop.
Assuntos
MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Modelos Moleculares , Bases de Dados de Proteínas , MAP Quinases Reguladas por Sinal Extracelular/antagonistas & inibidores , MAP Quinases Reguladas por Sinal Extracelular/química , Conformação Proteica , Dobramento de Proteína , Inibidores de Proteínas Quinases/química , Inibidores de Proteínas Quinases/farmacologia , Especificidade por SubstratoRESUMO
Amplification and overexpression of erbB2 (Her-2/neu) proto-oncogene has been linked to human malignancies including tumors of the breast, ovary, and stomach. It has been implicated in tumor growth, sensitivity to standard chemotherapy, prognosis of patients, and disease-free survival. Although the clinical use of trastuzumab (Herceptin) has prolonged the survival of breast cancer patients with erbB2-overexpressing tumors, there is an urgent need for more potent and orally bioavailable small-molecule inhibitors. CP-724,714 is a potent inhibitor of erbB2 receptor autophosphorylation in intact cells and is currently undergoing phase I clinical trials. Here, we describe the effects of CP-724,714 in vitro and in vivo in human breast cancer models. CP-724,714 is selective for inhibiting growth of HER2-driven cell lines. In addition, we show that it induces G1 cell cycle block in erbB2-overexpressing BT-474 human breast carcinoma cells and inhibits erbB2 autophosphorylation in xenografts when administered p.o. to athymic mice. It induces a marked reduction of extracellular signal-regulated kinase and Akt phosphorylation, tumor cell apoptosis, and release of caspase-3. P.o. administration (q.d. or b.i.d.) of CP-724,714 inhibits the growth of erbB2-overexpressing tumors in athymic mice without overt adverse effects.
Assuntos
Inibidores de Proteínas Quinases/farmacologia , Quinazolinas/farmacologia , Receptor ErbB-2/antagonistas & inibidores , Animais , Apoptose/efeitos dos fármacos , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Ciclo Celular/efeitos dos fármacos , Processos de Crescimento Celular/efeitos dos fármacos , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Feminino , Humanos , Camundongos , Camundongos Nus , Células NIH 3T3 , Fosforilação/efeitos dos fármacos , Proto-Oncogene Mas , Proteínas Proto-Oncogênicas c-akt/metabolismo , Receptor ErbB-2/metabolismo , Ensaios Antitumorais Modelo de XenoenxertoRESUMO
Lead-like drugs, or drugs below molecular weight 300, are an important and sometimes overlooked component of the current pharmacopeia and contemporary medicinal chemistry practice. To examine the recent state-of-the-art in lead-like drug discovery, we surveyed recent drug approvals from 2011 to 2017 and top 200 prescribed medications, as well as provide case studies on recently approved lead-like drugs. Many of these recent drugs are close analogs of previously known drugs or natural substrates, with a key focus of their medicinal chemistry optimization being the choice of a low molecular weight starting point and maintaining low molecular weight during the optimization. However, the identification of low molecular weight starting points may be limited by the availability of suitable low molecular weight screening sets. To increase the discovery rate of lead-like drugs, we suggest an increased focus on inclusion and prosecution of lead-like starting points in screening libraries.
Assuntos
Descoberta de Drogas , Avaliação Pré-Clínica de Medicamentos , Peso MolecularRESUMO
Sodium-phosphate cotransporter 2a, or NaPi2a (SLC34A1), is a solute-carrier (SLC) transporter located in the kidney proximal tubule that reabsorbs glomerular-filtered phosphate. Inhibition of NaPi2a may enhance urinary phosphate excretion and correct maladaptive mineral and hormonal derangements associated with increased cardiovascular risk in chronic kidney disease-mineral and bone disorder (CKD-MBD). To date, only nonselective NaPi inhibitors have been described. Herein, we detail the discovery of the first series of selective NaPi2a inhibitors, resulting from optimization of a high-throughput screening hit. The oral PK profile of inhibitor PF-06869206 (6f) in rodents allows for the exploration of the pharmacology of selective NaPi2a inhibition.
RESUMO
Studies have linked the serine-threonine kinase MAP4K4 to the regulation of a number of biological processes and/or diseases, including diabetes, cancer, inflammation, and angiogenesis. With a majority of the members of our lead series (e.g., 1) suffering from time-dependent inhibition (TDI) of CYP3A4, we sought design avenues that would eliminate this risk. One such approach arose from the observation that carboxylic acid-based intermediates employed in our discovery efforts retained high MAP4K4 inhibitory potency and were devoid of the TDI risk. The medicinal chemistry effort that led to the discovery of this central nervous system-impaired inhibitor together with its preclinical safety profile is described.
Assuntos
Aminopiridinas/síntese química , Aminopiridinas/farmacologia , Peptídeos e Proteínas de Sinalização Intracelular/antagonistas & inibidores , Inibidores de Proteínas Quinases/síntese química , Inibidores de Proteínas Quinases/farmacologia , Proteínas Serina-Treonina Quinases/antagonistas & inibidores , Aminopiridinas/efeitos adversos , Animais , Disponibilidade Biológica , Ácidos Carboxílicos/química , Inibidores do Citocromo P-450 CYP3A/síntese química , Inibidores do Citocromo P-450 CYP3A/farmacologia , Descoberta de Drogas , Meia-Vida , Lipopolissacarídeos/farmacologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Modelos Moleculares , Conformação Molecular , Inibidores de Proteínas Quinases/efeitos adversos , Ratos , Ratos Wistar , Relação Estrutura-Atividade , Fator de Necrose Tumoral alfa/sangueRESUMO
Optimization of the pharmacokinetic (PK) properties of a series of activators of adenosine monophosphate-activated protein kinase (AMPK) is described. Derivatives of the previously described 5-aryl-indole-3-carboxylic acid clinical candidate (1) were examined with the goal of reducing glucuronidation rate and minimizing renal excretion. Compounds 10 (PF-06679142) and 14 (PF-06685249) exhibited robust activation of AMPK in rat kidneys as well as desirable oral absorption, low plasma clearance, and negligible renal clearance in preclinical species. A correlation of in vivo renal clearance in rats with in vitro uptake by human and rat renal organic anion transporters (human OAT/rat Oat) was identified. Variation of polar functional groups was critical to mitigate active renal clearance mediated by the Oat3 transporter. Modification of either the 6-chloroindole core to a 4,6-difluoroindole or the 5-phenyl substituent to a substituted 5-(3-pyridyl) group provided improved metabolic stability while minimizing propensity for active transport by OAT3.
Assuntos
Proteínas Quinases Ativadas por AMP/efeitos dos fármacos , Ativadores de Enzimas/síntese química , Ativadores de Enzimas/farmacologia , Indóis/síntese química , Indóis/farmacologia , Animais , Ativação Enzimática/efeitos dos fármacos , Ativadores de Enzimas/farmacocinética , Humanos , Indóis/farmacocinética , Absorção Intestinal , Rim/efeitos dos fármacos , Rim/enzimologia , Masculino , Modelos Moleculares , Transportadores de Ânions Orgânicos Sódio-Independentes/metabolismo , Ratos , Ratos Wistar , Relação Estrutura-AtividadeRESUMO
Adenosine monophosphate-activated protein kinase (AMPK) is a protein kinase involved in maintaining energy homeostasis within cells. On the basis of human genetic association data, AMPK activators were pursued for the treatment of diabetic nephropathy. Identification of an indazole amide high throughput screening (HTS) hit followed by truncation to its minimal pharmacophore provided an indazole acid lead compound. Optimization of the core and aryl appendage improved oral absorption and culminated in the identification of indole acid, PF-06409577 (7). Compound 7 was advanced to first-in-human trials for the treatment of diabetic nephropathy.
Assuntos
Proteínas Quinases Ativadas por AMP/metabolismo , Nefropatias Diabéticas/tratamento farmacológico , Ativadores de Enzimas/química , Indóis/química , Administração Oral , Adsorção , Animais , Cristalografia por Raios X , Cães , Ativadores de Enzimas/síntese química , Ativadores de Enzimas/farmacocinética , Ativadores de Enzimas/farmacologia , Ensaios de Triagem em Larga Escala , Humanos , Indazóis/síntese química , Indazóis/química , Indazóis/farmacologia , Indóis/síntese química , Indóis/farmacocinética , Indóis/farmacologia , Injeções Intravenosas , Macaca fascicularis , Masculino , Modelos Moleculares , Conformação Proteica , RatosRESUMO
Mitogen-activated protein kinase 4 (MAP4K4) regulates the MEK kinase cascade and is implicated in cytoskeletal rearrangement and migration; however, identifying MAP4K4 substrates has remained a challenge. To ascertain MAP4K4-dependent phosphorylation events, we combined phosphoproteomic studies of MAP4K4 inhibition with in vitro assessment of its kinase specificity. We identified 235 phosphosites affected by MAP4K4 inhibition in cells and found that pTP and pSP motifs were predominant among them. In contrast, in vitro assessment of kinase specificity showed that MAP4K4 favors a pTL motif. We showed that MAP4K4 directly phosphorylates and coimmunoprecipitates with FERM, RhoGEF, and pleckstrin domain-containing protein 1 (FARP1). MAP4K4 inhibition in SH-SY5Y cells increases neurite outgrowth, a process known to involve FARP1. As FARP1 and MAP4K4 both contribute to cytoskeletal rearrangement, the results suggest that MAP4K4 exerts some of its effects on the cytoskeleton via phosphorylation of FARP1.
Assuntos
Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Proteínas Serina-Treonina Quinases/metabolismo , Fatores de Troca de Nucleotídeo Guanina Rho/metabolismo , Bioensaio , Células Hep G2 , Humanos , Estrutura Molecular , Fosforilação , ProteômicaRESUMO
Signalling pathways that control endothelial cell (EC) permeability, leukocyte adhesion and inflammation are pivotal for atherosclerosis initiation and progression. Here we demonstrate that the Sterile-20-like mitogen-activated protein kinase kinase kinase kinase 4 (MAP4K4), which has been implicated in inflammation, is abundantly expressed in ECs and in atherosclerotic plaques from mice and humans. On the basis of endothelial-specific MAP4K4 gene silencing and gene ablation experiments in Apoe(-/-) mice, we show that MAP4K4 in ECs markedly promotes Western diet-induced aortic macrophage accumulation and atherosclerotic plaque development. Treatment of Apoe(-/-) and Ldlr(-/-) mice with a selective small-molecule MAP4K4 inhibitor also markedly reduces atherosclerotic lesion area. MAP4K4 silencing in cultured ECs attenuates cell surface adhesion molecule expression while reducing nuclear localization and activity of NFκB, which is critical for promoting EC activation and atherosclerosis. Taken together, these results reveal that MAP4K4 is a key signalling node that promotes immune cell recruitment in atherosclerosis.
Assuntos
Aterosclerose/metabolismo , Células Endoteliais/metabolismo , Inflamação/metabolismo , Proteínas Serina-Treonina Quinases/metabolismo , Doenças Vasculares/metabolismo , Aminopiridinas/farmacologia , Animais , Apolipoproteínas E/genética , Apolipoproteínas E/metabolismo , Aterosclerose/genética , Regulação da Expressão Gênica/fisiologia , Inflamação/genética , Macrófagos , Masculino , Camundongos , Camundongos Knockout , NF-kappa B/genética , NF-kappa B/metabolismo , Proteínas Serina-Treonina Quinases/antagonistas & inibidores , Proteínas Serina-Treonina Quinases/genética , Receptores de LDL/genética , Receptores de LDL/metabolismo , Doenças Vasculares/genética , Quinase Induzida por NF-kappaBRESUMO
Several polar heteroaromatic acetic acids and their piperidine amides were synthesized and evaluated as ghrelin or type 1a growth hormone secretagogue receptor (GHS-R1a) inverse agonists. Efforts to improve pharmacokinetic and safety profile was achieved by modulating physicochemical properties and, more specifically, emphasizing increased polarity of our chemical series. ortho-Carboxamide containing compounds provided optimal physicochemical, pharmacologic, and safety profile. pH-dependent chemical stability was also assessed with our series.
RESUMO
Recent studies in adipose tissue, pancreas, muscle, and macrophages suggest that MAP4K4, a serine/threonine protein kinase may be a viable target for antidiabetic drugs. As part of the evaluation of MAP4K4 as a novel antidiabetic target, a tool compound, 16 (PF-6260933) and a lead 17 possessing excellent kinome selectivity and suitable properties were delivered to establish proof of concept in vivo. The medicinal chemistry effort that led to the discovery of these lead compounds is described herein together with in vivo pharmacokinetic properties and activity in a model of insulin resistance.
RESUMO
An "sp2 -sp3 Stille coupling" of the vinyl triflate 1 and the stannyl compound 2 is a key step toward the completion of the total synthesis of eleutherobin, a natural product exhibiting taxol-like cytotoxic activity.
RESUMO
Ghrelin is an endogenous peptide hormone secreted primarily by the stomach and is involved in a number of physiological processes including growth hormone secretion, food intake, as well as energy and glucose homeostasis. The physiological actions of ghrelin are mediated through the growth hormone secretagogue receptor 1a (ghrelin receptor), a peptidic G-protein-coupled receptor. This target has attracted much interest, as agents that block ghrelin's actions on its receptor are anticipated to be pharmaceutical interventions for a number of diseases. This review provides an overview of ghrelin biology with a focus on metabolic diseases and summarizes recent medicinal chemistry programs aimed at delivering small molecule ghrelin receptor antagonists and inverse agonists to the clinic.
Assuntos
Receptores de Grelina/antagonistas & inibidores , Aciltransferases/genética , Animais , Indústria Farmacêutica , Ingestão de Alimentos/efeitos dos fármacos , Grelina/genética , Grelina/farmacologia , Glucose/metabolismo , Homeostase/efeitos dos fármacos , Humanos , Obesidade/tratamento farmacológico , Pâncreas/efeitos dos fármacos , Pâncreas/fisiologia , Ratos , Receptores de Grelina/agonistas , Receptores de Grelina/genéticaRESUMO
Disrupting the binding interaction between proprotein convertase (PCSK9) and the epidermal growth factor-like domain A (EGF-A domain) in the low-density lipoprotein receptor (LDL-R) is a promising strategy to promote LDL-R recycling and thereby lower circulating cholesterol levels. In this study, truncated 26 amino acid EGF-A analogs were designed and synthesized, and their structures were analyzed in solution and in complex with PCSK9. The most potent peptide had an increased binding affinity for PCSK9 (KD = 0.6 µM) compared with wild-type EGF-A (KD = 1.2 µM), and the ability to increase LDL-R recycling in the presence of PCSK9 in a cell-based assay.
Assuntos
Peptídeos/metabolismo , Pró-Proteína Convertases/metabolismo , Receptores de LDL/metabolismo , Serina Endopeptidases/metabolismo , Sequência de Aminoácidos , Sítios de Ligação , Linhagem Celular , Colesterol/metabolismo , Fator de Crescimento Epidérmico/química , Transferência Ressonante de Energia de Fluorescência , Humanos , Simulação de Dinâmica Molecular , Dados de Sequência Molecular , Mutagênese , Peptídeos/síntese química , Peptídeos/química , Pró-Proteína Convertase 9 , Pró-Proteína Convertases/química , Pró-Proteína Convertases/genética , Ligação Proteica , Estrutura Secundária de Proteína , Estrutura Terciária de Proteína , Serina Endopeptidases/química , Serina Endopeptidases/genéticaRESUMO
The identification of potent, highly selective orally bioavailable ghrelin receptor inverse agonists from a spiro-azetidino-piperidine series is described. Examples from this series have promising in vivo pharmacokinetics and increase glucose-stimulated insulin secretion in human whole and dispersed islets. A physicochemistry-based strategy to increase lipophilic efficiency for ghrelin receptor potency and retain low clearance and satisfactory permeability while reducing off-target pharmacology led to the discovery of 16h. Compound 16h has a superior balance of ghrelin receptor pharmacology and off-target selectivity. On the basis of its promising pharmacological and safety profile, 16h was advanced to human clinical trials.
RESUMO
The Aurora family of highly related serine/threonine kinases plays a key role in the regulation of mitosis. Aurora1 and Aurora2 play important but distinct roles in the G(2) and M phases of the cell cycle and are essential for proper chromosome segregation and cell division. Overexpression and amplification of Aurora2 have been reported in different tumor types, including breast, colon, pancreatic, ovarian, and gastric cancer. PF-03814735 is a novel, potent, orally bioavailable, reversible inhibitor of both Aurora1 and Aurora2 kinases that is currently in phase I clinical trials for the treatment of advanced solid tumors. In intact cells, the inhibitory activity of PF-03814735 on the Aurora1 and Aurora2 kinases reduces levels of phospho-Aurora1, phosphohistone H3, and phospho-Aurora2. PF-03814735 produces a block in cytokinesis, resulting in inhibition of cell proliferation and the formation of polyploid multinucleated cells. Although PF-03814735 produces significant inhibition of several other protein kinases, the predominant biochemical effects in cellular assays are consistent with inhibition of Aurora kinases. Once-daily oral administration of PF-03814735 to mice bearing human xenograft tumors produces a reduction in phosphohistone H3 in tumors at doses that are tolerable and that result in significant inhibition of tumor growth. The combination of PF-03814735 and docetaxel in xenograft mouse tumor models shows additive tumor growth inhibition. These results support the clinical evaluation of PF-03814735 in cancer patients. Mol Cancer Ther; 9(4); 883-94. (c)2010 AACR.