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2.
Bioorg Med Chem Lett ; 29(4): 659-663, 2019 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-30638874

RESUMO

Screening of 100 acylsulfonamides from the Bristol-Myers Squibb compound collection identified the C3-cyclohexyl indole 6 as a potent Nav1.7 inhibitor. Replacement of the C2 furanyl ring of 6 with a heteroaryl moiety or truncation of this group led to the identification of 4 analogs with hNav1.7 IC50 values under 50 nM. Fluorine substitution of the truncated compound 12 led to 34 with improved potency and isoform selectivity. The inverted indole 36 also maintained good activity. Both 34 and 36 exhibited favorable CYP inhibition profiles, good membrane permeability and a low efflux ratio and, therefore, represent new leads in the search for potent and selective Nav1.7 inhibitors to treat pain.

3.
J Med Chem ; 62(2): 831-856, 2019 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-30576602

RESUMO

3-Aryl-indole and 3-aryl-indazole derivatives were identified as potent and selective Nav1.7 inhibitors. Compound 29 was shown to be efficacious in the mouse formalin assay and also reduced complete Freund's adjuvant (CFA)-induced thermal hyperalgesia and chronic constriction injury (CCI) induced cold allodynia and models of inflammatory and neuropathic pain, respectively, following intraperitoneal (IP) doses of 30 mg/kg. The observed efficacy could be correlated with the mouse dorsal root ganglion exposure and NaV1.7 potency associated with 29.

4.
ACS Med Chem Lett ; 9(5): 472-477, 2018 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-29795762

RESUMO

There is a significant unmet medical need for more efficacious and rapidly acting antidepressants. Toward this end, negative allosteric modulators of the N-methyl-d-aspartate receptor subtype GluN2B have demonstrated encouraging therapeutic potential. We report herein the discovery and preclinical profile of a water-soluble intravenous prodrug BMS-986163 (6) and its active parent molecule BMS-986169 (5), which demonstrated high binding affinity for the GluN2B allosteric site (Ki = 4.0 nM) and selective inhibition of GluN2B receptor function (IC50 = 24 nM) in cells. The conversion of prodrug 6 to parent 5 was rapid in vitro and in vivo across preclinical species. After intravenous administration, compounds 5 and 6 have exhibited robust levels of ex vivo GluN2B target engagement in rodents and antidepressant-like activity in mice. No significant off-target activity was observed for 5, 6, or the major circulating metabolites met-1 and met-2. The prodrug BMS-986163 (6) has demonstrated an acceptable safety and toxicology profile and was selected as a preclinical candidate for further evaluation in major depressive disorder.

5.
Bioorg Med Chem Lett ; 28(5): 958-962, 2018 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-29439904

RESUMO

Replacement of the piperidine ring in the lead benzenesulfonamide Nav1.7 inhibitor 1 with a weakly basic morpholine core resulted in a significant reduction in Nav1.7 inhibitory activity, but the activity was restored by shortening the linkage from methyleneoxy to oxygen. These efforts led to a series of morpholine-based aryl sulfonamides as isoform-selective Nav1.7 inhibitors. This report describes the synthesis and SAR of these analogs.


Assuntos
Morfolinas/farmacologia , Canal de Sódio Disparado por Voltagem NAV1.7/metabolismo , Sulfonamidas/farmacologia , Bloqueadores do Canal de Sódio Disparado por Voltagem/farmacologia , Relação Dose-Resposta a Droga , Humanos , Estrutura Molecular , Morfolinas/química , Relação Estrutura-Atividade , Sulfonamidas/síntese química , Sulfonamidas/química , Bloqueadores do Canal de Sódio Disparado por Voltagem/síntese química , Bloqueadores do Canal de Sódio Disparado por Voltagem/química
6.
J Pharmacol Exp Ther ; 363(3): 377-393, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28954811

RESUMO

(R)-3-((3S,4S)-3-fluoro-4-(4-hydroxyphenyl)piperidin-1-yl)-1-(4-methylbenzyl)pyrrolidin-2-one (BMS-986169) and the phosphate prodrug 4-((3S,4S)-3-fluoro-1-((R)-1-(4-methylbenzyl)-2-oxopyrrolidin-3-yl)piperidin-4-yl)phenyl dihydrogen phosphate (BMS-986163) were identified from a drug discovery effort focused on the development of novel, intravenous glutamate N-methyl-d-aspartate 2B receptor (GluN2B) negative allosteric modulators (NAMs) for treatment-resistant depression (TRD). BMS-986169 showed high binding affinity for the GluN2B subunit allosteric modulatory site (Ki = 4.03-6.3 nM) and selectively inhibited GluN2B receptor function in Xenopus oocytes expressing human N-methyl-d-aspartate receptor subtypes (IC50 = 24.1 nM). BMS-986169 weakly inhibited human ether-a-go-go-related gene channel activity (IC50 = 28.4 µM) and had negligible activity in an assay panel containing 40 additional pharmacological targets. Intravenous administration of BMS-986169 or BMS-986163 dose-dependently increased GluN2B receptor occupancy and inhibited in vivo [3H](+)-5-methyl-10,11-dihydro-5H-dibenzo[a,d]cyclohepten-5,10-imine ([3H]MK-801) binding, confirming target engagement and effective cleavage of the prodrug. BMS-986169 reduced immobility in the mouse forced swim test, an effect similar to intravenous ketamine treatment. Decreased novelty suppressed feeding latency, and increased ex vivo hippocampal long-term potentiation was also seen 24 hours after acute BMS-986163 or BMS-986169 administration. BMS-986169 did not produce ketamine-like hyperlocomotion or abnormal behaviors in mice or cynomolgus monkeys but did produce a transient working memory impairment in monkeys that was closely related to plasma exposure. Finally, BMS-986163 produced robust changes in the quantitative electroencephalogram power band distribution, a translational measure that can be used to assess pharmacodynamic activity in healthy humans. Due to the poor aqueous solubility of BMS-986169, BMS-986163 was selected as the lead GluN2B NAM candidate for further evaluation as a novel intravenous agent for TRD.


Assuntos
Antidepressivos/uso terapêutico , Transtorno Depressivo Maior/tratamento farmacológico , Organofosfatos/uso terapêutico , Piperidinas/uso terapêutico , Pró-Fármacos/uso terapêutico , Pirrolidinonas/uso terapêutico , Receptores de N-Metil-D-Aspartato/metabolismo , Administração Intravenosa , Regulação Alostérica , Animais , Antidepressivos/efeitos adversos , Antidepressivos/farmacocinética , Encéfalo/efeitos dos fármacos , Encéfalo/metabolismo , Encéfalo/fisiopatologia , Ondas Encefálicas/efeitos dos fármacos , Transtorno Depressivo Maior/fisiopatologia , Transtorno Depressivo Maior/psicologia , Transtornos Dissociativos/induzido quimicamente , Macaca fascicularis , Masculino , Memória de Curto Prazo/efeitos dos fármacos , Camundongos , Atividade Motora/efeitos dos fármacos , Organofosfatos/efeitos adversos , Organofosfatos/farmacocinética , Piperidinas/efeitos adversos , Piperidinas/farmacocinética , Pró-Fármacos/efeitos adversos , Pró-Fármacos/farmacocinética , Pirrolidinonas/efeitos adversos , Pirrolidinonas/farmacocinética , Ensaio Radioligante , Ratos Sprague-Dawley , Receptores de N-Metil-D-Aspartato/antagonistas & inibidores , Xenopus
7.
Bioorg Med Chem ; 25(20): 5490-5505, 2017 10 15.
Artigo em Inglês | MEDLINE | ID: mdl-28818462

RESUMO

Since zwitterionic benzenesulfonamide Nav1.7 inhibitors suffer from poor membrane permeability, we sought to eliminate this characteristic by replacing the basic moiety with non-basic bicyclic acetals and monocyclic ethers. These efforts led to the discovery of the non-zwitterionic aryl sulfonamide 49 as a selective Nav1.7 inhibitor with improved membrane permeability. Despite its moderate cellular activity, 49 exhibited robust efficacy in mouse models of neuropathic and inflammatory pain and modulated translational electromyogram measures associated with activation of nociceptive neurons.


Assuntos
Descoberta de Drogas , Modelos Biológicos , Canal de Sódio Disparado por Voltagem NAV1.7/metabolismo , Neurônios/efeitos dos fármacos , Nociceptividade/efeitos dos fármacos , Sulfonamidas/farmacologia , Administração Oral , Animais , Dor Crônica/induzido quimicamente , Dor Crônica/tratamento farmacológico , Modelos Animais de Doenças , Relação Dose-Resposta a Droga , Adjuvante de Freund , Células HEK293 , Humanos , Inflamação/induzido quimicamente , Inflamação/tratamento farmacológico , Masculino , Camundongos , Estrutura Molecular , Neurônios/metabolismo , Relação Estrutura-Atividade , Sulfonamidas/administração & dosagem , Sulfonamidas/química
8.
Eur J Pharmacol ; 812: 104-112, 2017 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-28690193

RESUMO

Alzheimer's disease is associated with the accumulation of amyloid-ß (Aß) in the brain. In particular, the 42-amino acid form, Aß1-42, is thought to play a key role in the disease. It is therefore of interest that diverse compounds, known as γ-secretase modulators (GSM), can selectively decrease Aß1-42 production without inhibiting the production of other forms of Aß. Here we describe the novel discovery of synergistic inhibition of Aß by certain combinations of GSMs. Cell cultures were treated with pairwise combinations of GSMs to determine how Aß peptide production was affected. Analysis of isobolograms and calculation of the combination index showed that BMS-869780 and GSM-2 were highly synergistic. Additional combinations of GSMs revealed that inhibition of Aß occurred only when one GSM was of the "acid GSM" structural class and the other was of the "non-acid GSM" class. A total of 15 representative acid/non-acid GSM combinations were shown to inhibit Aß production, whereas 10 pairwise combinations containing two acid GSMs or containing two non-acid GSMs did not inhibit Aß. We also discovered that lasalocid, a natural product, is a potent GSM. Lasalocid is unique in that it did not synergize with other GSMs. Synergism did not translate in vivo perhaps because of biochemical differences between the cell culture model and brain. These findings reinforce the pharmacological differences between different structural classes of GSMs, and may help to exploit the potential of γ-secretase as a drug target.


Assuntos
Secretases da Proteína Precursora do Amiloide/antagonistas & inibidores , Peptídeos beta-Amiloides/biossíntese , Fragmentos de Peptídeos/biossíntese , Inibidores de Proteases/farmacologia , Acetatos/farmacologia , Animais , Linhagem Celular Tumoral , Sinergismo Farmacológico , Humanos , Camundongos , Piperidinas/farmacologia
9.
J Med Chem ; 60(6): 2513-2525, 2017 Mar 23.
Artigo em Inglês | MEDLINE | ID: mdl-28234467

RESUMO

By taking advantage of certain features in piperidine 4, we developed a novel series of cyclohexylamine- and piperidine-based benzenesulfonamides as potent and selective Nav1.7 inhibitors. However, compound 24, one of the early analogs, failed to reduce phase 2 flinching in the mouse formalin test even at a dose of 100 mpk PO due to insufficient dorsal root ganglion (DRG) exposure attributed to poor membrane permeability. Two analogs with improved membrane permeability showed much increased DRG concentrations at doses of 30 mpk PO, but, confoundingly, only one of these was effective in the formalin test. More data are needed to understand the disconnect between efficacy and exposure relationships.


Assuntos
Analgésicos/química , Analgésicos/uso terapêutico , Dor/tratamento farmacológico , Sulfonamidas/química , Sulfonamidas/uso terapêutico , Bloqueadores do Canal de Sódio Disparado por Voltagem/química , Bloqueadores do Canal de Sódio Disparado por Voltagem/uso terapêutico , Analgésicos/farmacocinética , Analgésicos/farmacologia , Animais , Descoberta de Drogas , Gânglios Espinais/efeitos dos fármacos , Gânglios Espinais/metabolismo , Células HEK293 , Humanos , Masculino , Camundongos , Canal de Sódio Disparado por Voltagem NAV1.7/metabolismo , Dor/metabolismo , Piperidinas/química , Piperidinas/farmacocinética , Piperidinas/farmacologia , Piperidinas/uso terapêutico , Sulfonamidas/farmacocinética , Sulfonamidas/farmacologia , Bloqueadores do Canal de Sódio Disparado por Voltagem/farmacocinética , Bloqueadores do Canal de Sódio Disparado por Voltagem/farmacologia
10.
Bioorg Med Chem Lett ; 26(23): 5729-5731, 2016 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-27816517

RESUMO

This Letter describes the synthesis and structure-activity relationships of a series of furo[2,3-d][1,3]thiazinamine BACE1 inhibitors. The co-crystal structure of a representative thiazinamine 2e bound with the BACE1 active site displayed a binding mode driven by interactions with the catalytic aspartate dyad and engagement of the biaryl amide toward the S1 and S3 pockets. This work indicates that furo[2,3-d]thiazine can serve as a viable bioisostere of the known furo[3,4-d]thiazine.


Assuntos
Doença de Alzheimer/tratamento farmacológico , Secretases da Proteína Precursora do Amiloide/antagonistas & inibidores , Ácido Aspártico Endopeptidases/antagonistas & inibidores , Inibidores Enzimáticos/química , Inibidores Enzimáticos/farmacologia , Furanos/química , Furanos/farmacologia , Tiazinas/química , Tiazinas/farmacologia , Doença de Alzheimer/metabolismo , Secretases da Proteína Precursora do Amiloide/química , Secretases da Proteína Precursora do Amiloide/metabolismo , Ácido Aspártico Endopeptidases/química , Ácido Aspártico Endopeptidases/metabolismo , Domínio Catalítico , Humanos , Modelos Moleculares , Ligação Proteica
11.
J Med Chem ; 59(18): 8593-600, 2016 09 22.
Artigo em Inglês | MEDLINE | ID: mdl-27559936

RESUMO

Truncation of the S3 substituent of the biaryl aminothiazine 2, a potent BACE1 inhibitor, led to a low molecular weight aminothiazine 5 with moderate activity. Despite its moderate activity, compound 5 demonstrated significant brain Aß reduction in rodents. The metabolic instability of 5 was overcome by the replacement of the 6-dimethylisoxazole, a metabolic soft spot, with a pyrimidine ring. Thus, truncation of the S3 substituent represents a viable approach to the discovery of orally bioavailable, brain-penetrant BACE1 inhibitors.


Assuntos
Secretases da Proteína Precursora do Amiloide/antagonistas & inibidores , Peptídeos beta-Amiloides/metabolismo , Ácido Aspártico Endopeptidases/antagonistas & inibidores , Inibidores Enzimáticos/química , Inibidores Enzimáticos/farmacologia , Tiazinas/química , Tiazinas/farmacologia , Aminação , Secretases da Proteína Precursora do Amiloide/metabolismo , Animais , Ácido Aspártico Endopeptidases/metabolismo , Encéfalo/efeitos dos fármacos , Encéfalo/metabolismo , Inibidores Enzimáticos/sangue , Humanos , Camundongos , Simulação de Acoplamento Molecular , Ratos , Relação Estrutura-Atividade , Tiazinas/sangue
12.
J Pharmacol Exp Ther ; 358(1): 138-50, 2016 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-27189973

RESUMO

The pharmacokinetics, pharmacodynamics, safety, and tolerability of BMS-932481, a γ-secretase modulator (GSM), were tested in healthy young and elderly volunteers after single and multiple doses. BMS-932481 was orally absorbed, showed dose proportionality after a single dose administration, and had approximately 3-fold accumulation after multiple dosing. High-fat/caloric meals doubled the Cmax and area under the curve and prolonged Tmax by 1.5 hours. Consistent with the preclinical pharmacology of GSMs, BMS-932481 decreased cerebrospinal fluid (CSF) Aß39, Aß40, and Aß42 while increasing Aß37 and Aß38, thereby providing evidence of γ-secretase enzyme modulation rather than inhibition. In plasma, reductions in Aß40 and Aß42 were observed with no change in total Aß; in CSF, modest decreases in total Aß were observed at higher dose levels. Increases in liver enzymes were observed at exposures associated with greater than 70% CSF Aß42 lowering after multiple dosing. Although further development was halted due to an insufficient safety margin to test the hypothesis for efficacy of Aß lowering in Alzheimer's disease, this study demonstrates that γ-secretase modulation is achievable in healthy human volunteers and supports further efforts to discover well tolerated GSMs for testing in Alzheimer's disease and other indications.


Assuntos
Secretases da Proteína Precursora do Amiloide/metabolismo , Peptídeos beta-Amiloides , Compostos de Anilina/farmacologia , Compostos de Anilina/farmacocinética , Anti-Inflamatórios não Esteroides/farmacologia , Anti-Inflamatórios não Esteroides/farmacocinética , Pirimidinas/farmacologia , Pirimidinas/farmacocinética , Adolescente , Adulto , Doença de Alzheimer/tratamento farmacológico , Doença de Alzheimer/enzimologia , Peptídeos beta-Amiloides/sangue , Peptídeos beta-Amiloides/líquido cefalorraquidiano , Compostos de Anilina/efeitos adversos , Compostos de Anilina/química , Anti-Inflamatórios não Esteroides/efeitos adversos , Anti-Inflamatórios não Esteroides/química , Área Sob a Curva , Cromatografia Líquida , Relação Dose-Resposta a Droga , Método Duplo-Cego , Feminino , Voluntários Saudáveis , Humanos , Limite de Detecção , Masculino , Espectrometria de Massas , Pessoa de Meia-Idade , Pirimidinas/efeitos adversos , Pirimidinas/química , Adulto Jovem
13.
J Pharmacol Exp Ther ; 358(1): 125-37, 2016 07.
Artigo em Inglês | MEDLINE | ID: mdl-27189974

RESUMO

The amyloid-ß peptide (Aß)-in particular, the 42-amino acid form, Aß1-42-is thought to play a key role in the pathogenesis of Alzheimer's disease (AD). Thus, several therapeutic modalities aiming to inhibit Aß synthesis or increase the clearance of Aß have entered clinical trials, including γ-secretase inhibitors, anti-Aß antibodies, and amyloid-ß precursor protein cleaving enzyme inhibitors. A unique class of small molecules, γ-secretase modulators (GSMs), selectively reduce Aß1-42 production, and may also decrease Aß1-40 while simultaneously increasing one or more shorter Aß peptides, such as Aß1-38 and Aß1-37. GSMs are particularly attractive because they do not alter the total amount of Aß peptides produced by γ-secretase activity; they spare the processing of other γ-secretase substrates, such as Notch; and they do not cause accumulation of the potentially toxic processing intermediate, ß-C-terminal fragment. This report describes the translation of pharmacological activity across species for two novel GSMs, (S)-7-(4-fluorophenyl)-N2-(3-methoxy-4-(3-methyl-1H-1,2,4-triazol-1-yl)phenyl)-N4-methyl-6,7-dihydro-5H-cyclopenta[d]pyrimidine-2,4-diamine (BMS-932481) and (S,Z)-17-(4-chloro-2-fluorophenyl)-34-(3-methyl-1H-1,2,4-triazol-1-yl)-16,17-dihydro-15H-4-oxa-2,9-diaza-1(2,4)-cyclopenta[d]pyrimidina-3(1,3)-benzenacyclononaphan-6-ene (BMS-986133). These GSMs are highly potent in vitro, exhibit dose- and time-dependent activity in vivo, and have consistent levels of pharmacological effect across rats, dogs, monkeys, and human subjects. In rats, the two GSMs exhibit similar pharmacokinetics/pharmacodynamics between the brain and cerebrospinal fluid. In all species, GSM treatment decreased Aß1-42 and Aß1-40 levels while increasing Aß1-38 and Aß1-37 by a corresponding amount. Thus, the GSM mechanism and central activity translate across preclinical species and humans, thereby validating this therapeutic modality for potential utility in AD.


Assuntos
Secretases da Proteína Precursora do Amiloide/metabolismo , Peptídeos beta-Amiloides/antagonistas & inibidores , Compostos de Anilina/farmacologia , Compostos de Anilina/farmacocinética , Encéfalo/efeitos dos fármacos , Hidrocarbonetos Aromáticos com Pontes/farmacologia , Hidrocarbonetos Aromáticos com Pontes/farmacocinética , Pirimidinas/farmacologia , Pirimidinas/farmacocinética , Peptídeos beta-Amiloides/líquido cefalorraquidiano , Peptídeos beta-Amiloides/genética , Compostos de Anilina/química , Animais , Encéfalo/enzimologia , Encéfalo/metabolismo , Hidrocarbonetos Aromáticos com Pontes/química , Linhagem Celular , Cães , Relação Dose-Resposta a Droga , Avaliação Pré-Clínica de Medicamentos , Feminino , Humanos , Macaca fascicularis , Pirimidinas/química , Ratos Sprague-Dawley , Receptores Notch/metabolismo , Especificidade da Espécie , Distribuição Tecidual
14.
J Org Chem ; 81(8): 3386-90, 2016 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-27002691

RESUMO

Michael addition of thiourea to enones with subsequent intramolecular aminal ether formation provided easy access to furo[2,3-d]thiazinamines and pyrano[2,3-d][1,3]thiazin-2-amines. These amines served as versatile intermediates to a variety of beta-amyloid cleaving enzyme-1 (BACE1) inhibitors.

15.
ACS Med Chem Lett ; 7(3): 271-6, 2016 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-26985314

RESUMO

By targeting the flap backbone of the BACE1 active site, we discovered 6-dimethylisoxazole-substituted biaryl aminothiazine 18 with 34-fold improved BACE1 inhibitory activity over the lead compound 1. The cocrystal structure of 18 bound to the active site indicated two hydrogen-bond interactions between the dimethylisoxazole and threonine 72 and glutamine 73 of the flap. Incorporation of the dimethylisoxazole substitution onto the related aminothiazine carboxamide series led to pyrazine-carboxamide 26 as a very potent BACE1 inhibitor (IC50 < 1 nM). This compound demonstrated robust brain Aß reduction in rat dose-response studies. Thus, compound 26 may be useful in testing the amyloid hypothesis of Alzheimer's disease.

16.
Bioorg Med Chem Lett ; 26(6): 1554-1557, 2016 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-26898338

RESUMO

This Letter describes an efficient ring-closing metathesis approach to 2-chloro-4-amino-pyrimido[4,5-c]azepines and 2-chloro-4-amino-pyrimido[4,5-c]oxepines. These chlorides were applied to the synthesis of several potent γ-secretase modulators (GSMs).


Assuntos
Secretases da Proteína Precursora do Amiloide/metabolismo , Azepinas/farmacologia , Oxepinas/farmacologia , Pirimidinas/farmacologia , Azepinas/síntese química , Azepinas/química , Relação Dose-Resposta a Droga , Humanos , Estrutura Molecular , Oxepinas/síntese química , Oxepinas/química , Pirimidinas/síntese química , Pirimidinas/química , Relação Estrutura-Atividade
18.
Bioorg Med Chem Lett ; 25(22): 5040-7, 2015 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-26497283

RESUMO

The synthesis, evaluation, and structure-activity relationships of a class of acyl guanidines which inhibit the BACE-1 enzyme are presented. The prolinyl acyl guanidine chemotype (7c), unlike compounds of the parent isothiazole chemotype (1), yielded compounds with good agreement between their enzymatic and cellular potency as well as a reduced susceptibility to P-gp efflux. Further improvements in potency and P-gp ratio were realized via a macrocyclization strategy. The in vivo profile in wild-type mice and P-gp effects for the macrocyclic analog 21c is presented.


Assuntos
Secretases da Proteína Precursora do Amiloide/antagonistas & inibidores , Ácido Aspártico Endopeptidases/antagonistas & inibidores , Guanidinas/farmacologia , Compostos Macrocíclicos/farmacologia , Prolina/análogos & derivados , Prolina/farmacologia , Inibidores de Proteases/farmacologia , Membro 1 da Subfamília B de Cassetes de Ligação de ATP/metabolismo , Peptídeos beta-Amiloides/biossíntese , Animais , Células CACO-2 , Catepsina D/antagonistas & inibidores , Catepsina E/antagonistas & inibidores , Cães , Guanidinas/síntese química , Humanos , Compostos Macrocíclicos/síntese química , Células Madin Darby de Rim Canino , Masculino , Camundongos , Simulação de Acoplamento Molecular , Pepsina A/antagonistas & inibidores , Prolina/síntese química , Inibidores de Proteases/síntese química
19.
J Neurosci ; 35(17): 6931-6, 2015 Apr 29.
Artigo em Inglês | MEDLINE | ID: mdl-25926467

RESUMO

Multiple small-molecule inhibitors of the ß-secretase enzyme (BACE1) are under preclinical or clinical investigation for Alzheimer's disease (AD). Prior work has illustrated robust lowering of central amyloid ß (Aß) after acute administration of BACE1 inhibitors. However, very few studies have assessed the overall impact of chronically administered BACE1 inhibitors on brain amyloid burden, neuropathology, and behavioral function in aged preclinical models. We investigated the effects of a potent nonbrain-penetrant BACE1 inhibitor, delivered directly to the brain using intracerebroventricular infusion in an aged transgenic mouse model. Intracerebroventricular infusion of the BACE1 inhibitor (0.3-23.5 µg/d) for 8 weeks, initiated in 17-month-old Tg2576 mice, produced dose-dependent increases in brain inhibitor concentrations (0.2-13 µm). BACE1 inhibition significantly reversed the behavioral deficit in contextual fear conditioning, and reduced brain Aß levels, plaque burden, and associated pathology (e.g., dystrophic neurites), with maximal effects attained with ∼1 µg/d dose. Strikingly, the BACE1 inhibitor also reversed amyloid pathology below baseline levels (amyloid burden at the start of treatment), without adversely affecting cerebral amyloid angiopathy, microhemorrhages, myelination, or neuromuscular function. Inhibitor-mediated decline in brain amyloid pathology was associated with an increase in microglial ramification. This is the first demonstration of chronically administered BACE1 inhibitor to activate microglia, reverse brain amyloid pathology, and elicit functional improvement in an aged transgenic mouse model. Thus, engagement of novel glial-mediated clearance mechanisms may drive disease-modifying therapeutic benefit with BACE1 inhibition in AD.


Assuntos
Secretases da Proteína Precursora do Amiloide/antagonistas & inibidores , Peptídeos beta-Amiloides/metabolismo , Ácido Aspártico Endopeptidases/antagonistas & inibidores , Encéfalo/patologia , Transtornos Cognitivos/tratamento farmacológico , Inibidores Enzimáticos/uso terapêutico , Microglia/efeitos dos fármacos , Fatores Etários , Secretases da Proteína Precursora do Amiloide/metabolismo , Precursor de Proteína beta-Amiloide/genética , Animais , Ácido Aspártico Endopeptidases/metabolismo , Encéfalo/efeitos dos fármacos , Encéfalo/metabolismo , Encéfalo/fisiologia , Transtornos Cognitivos/genética , Transtornos Cognitivos/patologia , Modelos Animais de Doenças , Medo/efeitos dos fármacos , Humanos , Infusões Intraventriculares , Masculino , Memória/efeitos dos fármacos , Camundongos , Camundongos Transgênicos , Microglia/patologia , Mutação/genética , Neurônios/efeitos dos fármacos , Neurônios/patologia
20.
Int J Alzheimers Dis ; 2014: 431858, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25097793

RESUMO

Alzheimer's disease is the most prevalent cause of dementia and is associated with accumulation of amyloid-ß peptide (Aß), particularly the 42-amino acid Aß1-42, in the brain. Aß1-42 levels can be decreased by γ-secretase modulators (GSM), which are small molecules that modulate γ-secretase, an enzyme essential for Aß production. BMS-869780 is a potent GSM that decreased Aß1-42 and Aß1-40 and increased Aß1-37 and Aß1-38, without inhibiting overall levels of Aß peptides or other APP processing intermediates. BMS-869780 also did not inhibit Notch processing by γ-secretase and lowered brain Aß1-42 without evidence of Notch-related side effects in rats. Human pharmacokinetic (PK) parameters were predicted through allometric scaling of PK in rat, dog, and monkey and were combined with the rat pharmacodynamic (PD) parameters to predict the relationship between BMS-869780 dose, exposure and Aß1-42 levels in human. Off-target and safety margins were then based on comparisons to the predicted exposure required for robust Aß1-42 lowering. Because of insufficient safety predictions and the relatively high predicted human daily dose of 700 mg, further evaluation of BMS-869780 as a potential clinical candidate was discontinued. Nevertheless, BMS-869780 demonstrates the potential of the GSM approach for robust lowering of brain Aß1-42 without Notch-related side effects.

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