RESUMO
In this article, the rationale for the design, synthesis, and biological evaluation of a series of N-type voltage-sensitive calcium channel (VSCC) blockers is described. N-Type VSCC blockers, such as ziconotide, have shown utility in several models of stroke and pain. Modification of the previously reported lead, 1a, led to several 4-(4-benzyloxylphenyl)piperidine structures with potent in vitro and in vivo activities. In this series, the most interesting compound, (S)-2-amino-1-{4-[(4-benzyloxy-phenyl)-(3-methyl-but-2-enyl)-amino]-p iperidin-1-yl}-4-methyl-pentan-1-one (11), blocked N-type calcium channels (IC(50) = 0.67 microM in the IMR32 assay) and was efficacious in the audiogenic DBA/2 seizure mouse model (ED(50) = 6 mg/kg, iv) as well as the antiwrithing model (ED(50) = 6 mg/kg, iv). Whole-cell voltage-clamp electrophysiology experiments demonstrated that compound 11 blocked N-type Ca(2+) channels and Na(+) channels in superior cervical ganglion neurons at similar concentrations. Compound 11, which showed superior in vivo efficacy, stands out as an interesting lead for further development of neurotherapeutic agents in this series.
Assuntos
Analgésicos não Narcóticos/síntese química , Anticonvulsivantes/síntese química , Bloqueadores dos Canais de Cálcio/síntese química , Neurônios/metabolismo , Piperidinas/síntese química , Estimulação Acústica , Analgésicos não Narcóticos/química , Analgésicos não Narcóticos/farmacocinética , Analgésicos não Narcóticos/farmacologia , Animais , Anticonvulsivantes/química , Anticonvulsivantes/farmacocinética , Anticonvulsivantes/farmacologia , Pressão Sanguínea/efeitos dos fármacos , Bloqueadores dos Canais de Cálcio/química , Bloqueadores dos Canais de Cálcio/farmacocinética , Bloqueadores dos Canais de Cálcio/farmacologia , Linhagem Celular , Frequência Cardíaca/efeitos dos fármacos , Humanos , Técnicas In Vitro , Ativação do Canal Iônico , Masculino , Camundongos , Camundongos Endogâmicos DBA , Microssomos Hepáticos/metabolismo , Medição da Dor , Técnicas de Patch-Clamp , Piperidinas/química , Piperidinas/farmacocinética , Piperidinas/farmacologia , Ratos , Ratos Sprague-Dawley , Ratos Wistar , Convulsões/tratamento farmacológicoRESUMO
Striatal-enriched protein tyrosine phosphatase (STEP) has been described as a regulator of multiple kinases and glutamate receptor subunits critical for synaptic plasticity. Published behavioral and biochemical characterization from the founder line of STEP knockout (KO) mice revealed superior cognitive performance, with enhanced phosphorylation of substrates such as ERK, Fyn and GluN2B; suggesting that inhibitors of STEP may have potential as therapeutic agents for the treatment of neuropsychiatric disorders. The objectives of this work aimed to replicate and extend the previously reported behavioral consequences of STEP knockout. Consistent with previous reported data, STEP KO mice demonstrated exploratory activity levels and similar motor coordination relative to WT littermate controls as well as intact memory in a Y-maze spatial novelty test. Interestingly, KO mice demonstrated deficits in pre-pulse inhibition as well as reduced seizure threshold relative to WT controls. Immunohistochemical staining of brains revealed the expected gene-dependent reduction in STEP protein confirming knockout in the mice. The present data confirm expression and localization of STEP and the absence in KO mice, and describe functional downstream implications of reducing STEP levels in vivo.
Assuntos
Comportamento Exploratório , Locomoção , Aprendizagem em Labirinto , Proteínas Tirosina Fosfatases não Receptoras/metabolismo , Animais , Encéfalo/metabolismo , Encéfalo/fisiologia , Encéfalo/fisiopatologia , Camundongos , Camundongos Endogâmicos C57BL , Pentilenotetrazol/toxicidade , Proteínas Tirosina Fosfatases não Receptoras/genética , Convulsões/induzido quimicamente , Convulsões/genética , Convulsões/fisiopatologiaRESUMO
Evidence suggests that 30-50% of patients suffering from major depressive disorder (MDD) are classified as suffering from treatment resistant depression (TRD) as they have an inadequate response to standard antidepressants. A key feature of this patient population is the increased incidence of co-morbid symptoms like anxiety and pain. Recognizing that current standards of care are largely focused on monoaminergic mechanisms of action (MOAs), innovative approaches to drug discovery for TRD are targeting glutamate hyperfunction. Here we describe the in vitro and in vivo profile of GRN-529, a novel negative allosteric modulator (NAM) of metabotropic glutamate receptor 5 (mGluR5). In cell based pharmacology assays, GRN-529 is a high affinity (Ki 5.4 nM), potent (IC50 3.1 nM) and selective (>1000-fold selective vs mGluR1) mGluR5 NAM. Acute administration of GRN-529 (0.1-30 mg/kg p.o.) had dose-dependent efficacy across a therapeutically relevant battery of animal models, comprising depression (decreased immobility time in tail suspension and forced swim tests) and 2 of the co-morbid symptoms overrepresented in TRD, namely anxiety (attenuation of stress-induced hyperthermia, and increased punished crossings in the four plate test) and pain (reversal of hyperalgesia due to sciatic nerve ligation or inflammation). The potential side effect liability of GRN-529 was also assessed using preclinical models: GRN-529 had no effect on rat sexual behavior or motor co-ordination (rotarod), however it impaired cognition in mice (social odor recognition). Efficacy and side effects of GRN-529 were compared to standard of care agents (antidepressant, anxiolytic or analgesics) and the tool mGluR5 NAM, MTEP. To assess the relationship between target occupancy and efficacy, ex vivo receptor occupancy was measured in parallel with efficacy testing. This revealed a strong correlation between target engagement, exposure and efficacy across behavioral endpoints, which supports the potential translational value of PET imaging to dose selection in patients. Collectively this broad spectrum profile of efficacy of GRN-529 supports our hypothesis that negative allosteric modulation of mGluR5 could represent an innovative therapeutic approach to the treatment of TRD. This article is part of a Special Issue entitled 'Metabotropic Glutamate Receptors'.
Assuntos
Regulação Alostérica/efeitos dos fármacos , Transtorno Depressivo Resistente a Tratamento/tratamento farmacológico , Antagonistas de Aminoácidos Excitatórios/uso terapêutico , Receptores de Glutamato Metabotrópico/antagonistas & inibidores , Regulação Alostérica/fisiologia , Analgésicos/farmacologia , Animais , Ansiolíticos/farmacologia , Antidepressivos/efeitos adversos , Antidepressivos/farmacologia , Antidepressivos/uso terapêutico , Comportamento Animal/efeitos dos fármacos , Benzamidas/efeitos adversos , Benzamidas/farmacologia , Benzamidas/uso terapêutico , Cálcio/metabolismo , Transtorno Depressivo Resistente a Tratamento/metabolismo , Transtorno Depressivo Resistente a Tratamento/fisiopatologia , Modelos Animais de Doenças , Relação Dose-Resposta a Droga , Avaliação Pré-Clínica de Medicamentos/métodos , Avaliação Pré-Clínica de Medicamentos/psicologia , Antagonistas de Aminoácidos Excitatórios/efeitos adversos , Antagonistas de Aminoácidos Excitatórios/farmacologia , Ácido Glutâmico/farmacologia , Células HEK293 , Humanos , Camundongos , Piridinas/efeitos adversos , Piridinas/farmacologia , Piridinas/uso terapêutico , Ensaio Radioligante/métodos , Ratos , Receptor de Glutamato Metabotrópico 5 , Receptores de Glutamato Metabotrópico/metabolismo , Receptores de Glutamato Metabotrópico/fisiologiaAssuntos
Analgésicos não Narcóticos/farmacologia , Bloqueadores dos Canais de Cálcio/farmacologia , Ácidos Pentanoicos/farmacologia , Administração Oral , Analgésicos não Narcóticos/química , Animais , Bloqueadores dos Canais de Cálcio/química , Canais de Cálcio Tipo L/efeitos dos fármacos , Canais de Cálcio Tipo N/efeitos dos fármacos , Linhagem Celular , Injeções Intravenosas , Masculino , Camundongos , Camundongos Endogâmicos DBA , Medição da Dor , Ácidos Pentanoicos/química , RatosRESUMO
Our drug discovery efforts for N-type calcium channel blockers in the 4-piperidinylaniline series led to the discovery of an orally active analgesic agent 26.1-[4-Dimethylamino-benzyl)-piperidin-4-yl]-[4-(3,3-dimethyl-but yl)-phenyl]-(3-methyl-but-2-enyl)amine (26) showed high affinity to functionally block N-type calcium channels (IC50=0.7 microM in the IMR32 assay) and exhibited high efficacy in the anti-writhing analgesia test with mice (ED50=12 mg/kg by po and 4 mg/kg by iv). In this report, the rationale for the design, synthesis, biological evaluation, and pharmacokinetics of this series of blockers is described.
Assuntos
Analgésicos/química , Analgésicos/farmacologia , Compostos de Anilina/química , Compostos de Anilina/farmacologia , Bloqueadores dos Canais de Cálcio/química , Bloqueadores dos Canais de Cálcio/farmacologia , Canais de Cálcio Tipo N/efeitos dos fármacos , Piperidinas/química , Piperidinas/farmacologia , Administração Oral , Analgésicos/síntese química , Compostos de Anilina/síntese química , Animais , Bloqueadores dos Canais de Cálcio/administração & dosagem , Bloqueadores dos Canais de Cálcio/síntese química , Linhagem Celular , Espectroscopia de Ressonância Magnética , Masculino , Espectrometria de Massas , Camundongos , Estrutura Molecular , Piperidinas/síntese química , Ratos , Ratos WistarRESUMO
Selective N-Type Voltage Sensitive Calcium Channel (VSCC) antagonists have shown utility in several models of pain and ischemia. We report the structure-activity relationship at the proximal phenyl group in a series of non-peptidyl VSCC blockers.
Assuntos
Compostos de Anilina/química , Compostos de Anilina/farmacologia , Bloqueadores dos Canais de Cálcio/química , Bloqueadores dos Canais de Cálcio/farmacologia , Leucina/análogos & derivados , Estimulação Acústica , Sequência de Aminoácidos , Compostos de Anilina/uso terapêutico , Animais , Bloqueadores dos Canais de Cálcio/uso terapêutico , Leucina/química , Leucina/farmacologia , Leucina/uso terapêutico , Camundongos , Camundongos Endogâmicos DBA , Dados de Sequência Molecular , Convulsões/tratamento farmacológico , Convulsões/fisiopatologia , Relação Estrutura-AtividadeRESUMO
Exploration of the SAR around the leucine side chain in a series of N,N-dialkyldipeptidylamines with potent functional activity at N-type VSCC is presented. A novel analog is disclosed which possesses improved aqueous solubility, in vivo activity in an audiogenic seizure model, and reversible blockade in electrophysiological assays.
Assuntos
Alcanos/química , Bloqueadores dos Canais de Cálcio/química , Canais de Cálcio Tipo N/metabolismo , Leucina/química , Oligopeptídeos/química , Alcanos/síntese química , Alcanos/farmacologia , Bloqueadores dos Canais de Cálcio/síntese química , Bloqueadores dos Canais de Cálcio/farmacologia , Canais de Cálcio Tipo N/efeitos dos fármacos , Dipeptídeos/síntese química , Dipeptídeos/química , Dipeptídeos/farmacologia , Eletrofisiologia , Oligopeptídeos/síntese química , Oligopeptídeos/farmacologia , Solubilidade , Relação Estrutura-Atividade , ômega-Conotoxinas/síntese química , ômega-Conotoxinas/química , ômega-Conotoxinas/farmacologiaRESUMO
Selective N-type voltage sensitive calcium channel (VSCC) blockers have shown utility in several models of stroke and pain. We are especially interested in small molecule N-type calcium channel blockers for therapeutic use. Herein, we report a series of N,N-dialkyl-dipeptidylamines with potent functional activity at N-type VSCCs and in vivo efficacy. The synthesis, SAR, and pharmacological evaluation of this series are discussed.
Assuntos
Bloqueadores dos Canais de Cálcio/síntese química , Diaminas/síntese química , Diaminas/farmacologia , Dipeptídeos/síntese química , Dipeptídeos/farmacologia , Animais , Modelos Animais de Doenças , Camundongos , Camundongos Endogâmicos DBA , Modelos Químicos , Convulsões/tratamento farmacológicoRESUMO
Several novel N-type voltage sensitive calcium channel blockers showed high affinity in the IMR32 assay and efficacy in the anti-writhing model. Herein, we describe the design, synthesis, SAR studies, biological data, physicochemical properties and pharmacokinetics of this 4-piperidinylaniline series.
Assuntos
Analgésicos não Narcóticos/farmacologia , Compostos de Anilina/farmacologia , Bloqueadores dos Canais de Cálcio/farmacologia , Canais de Cálcio Tipo N/efeitos dos fármacos , Animais , Bloqueadores dos Canais de Cálcio/síntese química , Camundongos , Relação Estrutura-AtividadeRESUMO
Selective N-type voltage sensitive calcium channel (VSCC) blockers have shown efficacy in several animal models of stroke and pain. In the process of searching for small molecule N-type calcium channel blockers, we have identified a series of N-methyl-N-aralkyl-peptidylamines with potent functional activity at N-type VSCCs. The most active compound discovered in this series is PD 173212 (11, IC50 = 36 nM in the IMR-32 assays). SAR and pharmacological evaluation of this series are described.