RESUMO
We have observed that molecular constructs based on multiple apoA-I mimetic peptides attached to a branched scaffold display promising anti-atherosclerosis functions in vitro. Building on these promising results, we now describe chronic in vivo studies to assess anti-atherosclerotic efficacy of HDL-like nanoparticles assembled from a trimeric construct, administered over 10 weeks either ip or orally to LDL receptor-null mice. When dosed ip, the trimer-based nanolipids markedly reduced plasma LDL-cholesterol levels by 40%, unlike many other apoA-I mimetic peptides, and were substantially atheroprotective. Surprisingly, these nanoparticles were also effective when administered orally at a dose of 75 mg/kg, despite the peptide construct being composed of l-amino acids and being undetectable in the plasma. The orally administered nanoparticles reduced whole aorta lesion areas by 55% and aortic sinus lesion volumes by 71%. Reductions in plasma cholesterol were due to the loss of non-HDL lipoproteins, while plasma HDL-cholesterol levels were increased. At a 10-fold lower oral dose, the nanoparticles were marginally effective in reducing atherosclerotic lesions. Intriguingly, analogous results were obtained with nanolipids of the corresponding monomeric peptide. These nanolipid formulations provide an avenue for developing orally efficacious therapeutic agents to manage atherosclerosis.
Assuntos
Apolipoproteína A-I , Lipoproteínas HDL/química , Lipoproteínas HDL/farmacologia , Nanopartículas/química , Receptores de LDL/metabolismo , Animais , Feminino , Lipoproteínas HDL/metabolismo , Camundongos , Camundongos Knockout , Peptidomiméticos/química , Peptidomiméticos/farmacologia , Receptores de LDL/genéticaAssuntos
Inibidores da Captação Adrenérgica/química , Deutério/química , Aprovação de Drogas , Descoberta de Drogas , Tetrabenazina/análogos & derivados , Inibidores da Captação Adrenérgica/efeitos adversos , Inibidores da Captação Adrenérgica/metabolismo , Inibidores da Captação Adrenérgica/uso terapêutico , Animais , Bioquímica/métodos , Coreia/tratamento farmacológico , Deutério/efeitos adversos , Deutério/metabolismo , Deutério/uso terapêutico , Aprovação de Drogas/métodos , Descoberta de Drogas/métodos , Controle de Medicamentos e Entorpecentes/métodos , Humanos , Discinesia Tardia/tratamento farmacológico , Tetrabenazina/efeitos adversos , Tetrabenazina/química , Tetrabenazina/metabolismo , Tetrabenazina/uso terapêuticoRESUMO
We describe an approach for engineering peptide-lipid nanoparticles that function similarly to high-density lipoprotein (HDL). Branched, multivalent constructs, bearing multiple 23- or 16-amino-acid peptides, were designed, synthesized, and combined with phospholipids to produce nanometer-scale discoidal HDL-like particles. A variety of biophysical techniques were employed to characterize the constructs, including size exclusion chromatography, analytical ultracentrifuge sedimentation, circular dichroism, transmission electron microscopy, and fluorescence spectroscopy. The nanoparticles functioned in vitro (human and mouse plasma) and in vivo (mice) to rapidly remodel large native HDLs into small lipid-poor HDL particles, which are key acceptors of cholesterol in reverse cholesterol transport. Fluorescent labeling studies showed that the constituents of the nanoparticles readily distributed into native HDLs, such that the peptide constructs coexisted with apolipoprotein A-I (apoA-I), the main structural protein in HDLs. Importantly, nanolipid particles containing multivalent peptides promoted efficient cellular cholesterol efflux and were functionally superior to those derived from monomeric apoA-I mimetic peptides. The multivalent peptide-lipid nanoparticles were also remarkably stable toward enzymatic digestion in vitro and displayed long half-lives and desirable pharmacokinetic profiles in mice, providing a real practical advantage over previously studied linear or tandem helical peptides. Encouragingly, a two-week exploratory efficacy study in a widely used animal model for atherosclerosis research (LDLr-null mice) using nanoparticles constructed from a trimeric peptide demonstrated an exceptional 50% reduction in the plasma total cholesterol levels compared to the control group. Altogether, the studies reported here point to an attractive avenue for designing synthetic, HDL-like nanoparticles, with potential for treating atherosclerosis.
Assuntos
Lipoproteínas HDL/química , Nanopartículas/química , Peptídeos/química , Animais , Aterosclerose/tratamento farmacológico , Modelos Animais de Doenças , Humanos , Lipoproteínas HDL/sangue , Lipoproteínas HDL/uso terapêutico , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Knockout , Modelos Moleculares , Estrutura Molecular , Nanopartículas/uso terapêutico , Peptídeos/sangue , Peptídeos/uso terapêutico , Receptores de LDL/deficiênciaRESUMO
Inhibitors of ketohexokinase (KHK) have potential for the treatment of diabetes and obesity. We have continued studies on a pyrimidinopyrimidine series of potent KHK inhibitors by exploring the 2-position substituent (R(3)) that interacts with Asp-27B in the ATP-binding region of KHK (viz. 1, 2; Table 1). We found that increased spacing between the terminal ammonium group and the heterocyclic scaffold (viz. 16-20), such that interaction with Asp-27B is not possible, still results in potent KHK inhibition (IC(50)=15-50 nM). We propose a new interaction with Asp-194, which serves to expand the pyrimidinopyrimidine pharmacophore.
Assuntos
Inibidores Enzimáticos/química , Frutoquinases/antagonistas & inibidores , Ligantes , Pirimidinas/química , Sítios de Ligação , Simulação por Computador , Cristalografia por Raios X , Inibidores Enzimáticos/síntese química , Inibidores Enzimáticos/metabolismo , Frutoquinases/metabolismo , Células Hep G2 , Humanos , Ligação Proteica , Estrutura Terciária de Proteína , Pirimidinas/síntese química , Pirimidinas/metabolismoRESUMO
RATIONALE: Mast cells and neutrophils are key contributors to the pathophysiological inflammatory processes that underpin asthma and chronic obstructive pulmonary disease, partly through the release of noxious serine proteases, including cathepsin G (Cat G) and chymase. From this standpoint, a dual inhibitor of neutrophil Cat G and mast cell chymase could protect against these disease-related inflammatory responses. OBJECTIVES: We examined the antiinflammatory pharmacology of RWJ-355871, a dual inhibitor of Cat G and chymase, in animal models of inflammation that evince pathophysiological pathways relevant to asthma and chronic obstructive pulmonary disease to determine the therapeutic potential of this compound. METHODS: In an ovalbumin (OVA)-sensitized rat model, RWJ-355871 was administered to block the mast-cell-mediated increase in paw volume caused by OVA injection. In a sheep asthma model, antigen-induced airway responses were assessed with and without aerosol treatment with RWJ-355871. In a murine tobacco-smoke model of airway inflammation, the effect of RWJ-355871 on smoke-induced neutrophilia was determined. MEASUREMENTS AND MAIN RESULTS: Intravenous treatment of OVA-sensitized rats with RWJ-355871 provided dose-dependent reduction in the increase in rat paw volume. In allergic sheep, aerosol pretreatment with RWJ-355871 showed dose-dependent inhibition of the antigen-induced early response, late response, and post-antigen-induced airway hyperreponsiveness. In tobacco-smoke-exposed mice, nebulized RWJ-355871 significantly reduced the smoke-induced neutrophilia from the levels observed in untreated mice. CONCLUSIONS: The preclinical antiinflammatory effects of RWJ-355871 in these animal models of inflammation indicate that this dual inhibitor may have therapeutic utility for treating airway inflammatory diseases involving mechanisms that depend on Cat G and/or chymase.
Assuntos
Catepsina G/antagonistas & inibidores , Quimases/antagonistas & inibidores , Pneumopatias/enzimologia , Organofosfonatos/uso terapêutico , Piperidinas/uso terapêutico , Doença Pulmonar Obstrutiva Crônica/enzimologia , Animais , Biomarcadores/metabolismo , Líquido da Lavagem Broncoalveolar/química , Catepsina G/metabolismo , Quimases/metabolismo , Modelos Animais de Doenças , Relação Dose-Resposta a Droga , Ensaio de Imunoadsorção Enzimática , Feminino , Injeções Intravenosas , Pneumopatias/tratamento farmacológico , Camundongos , Organofosfonatos/administração & dosagem , Piperidinas/administração & dosagem , Doença Pulmonar Obstrutiva Crônica/tratamento farmacológico , Ratos , Ovinos , Resultado do TratamentoRESUMO
Collagens are integral structural proteins in animal tissues and play key functional roles in cellular modulation. We sought to discover collagen model peptides (CMPs) that would form triple helices and self-assemble into supramolecular fibrils exhibiting collagen-like biological activity without preorganizing the peptide chains by covalent linkages. This challenging objective was accomplished by placing aromatic groups on the ends of a representative 30-mer CMP, (GPO)(10), as with l-phenylalanine and l-pentafluorophenylalanine in 32-mer 1a. Computational studies on homologous 29-mers 1a'-d' (one less GPO), as pairs of triple helices interacting head-to-tail, yielded stabilization energies in the order 1a' > 1b' > 1c' > 1d', supporting the hypothesis that hydrophobic aromatic groups can drive CMP self-assembly. Peptides 1a-d were studied comparatively relative to structural properties and ability to stimulate human platelets. Although each 32-mer formed stable triple helices (CD) spectroscopy, only 1a and 1b self-assembled into micrometer-scale fibrils. Light microscopy images for 1a depicted long collagen-like fibrils, whereas images for 1d did not. Atomic force microscopy topographical images indicated that 1a and 1b self-organize into microfibrillar species, whereas 1c and 1d do not. Peptides 1a and 1b induced the aggregation of human blood platelets with a potency similar to type I collagen, whereas 1c was much less effective, and 1d was inactive (EC(50) potency: 1a/1b >> 1c > 1d). Thus, 1a and 1b spontaneously self-assemble into thrombogenic collagen-mimetic materials because of hydrophobic aromatic interactions provided by the special end-groups. These findings have important implications for the design of biofunctional CMPs.
Assuntos
Colágenos Fibrilares/química , Peptídeos/química , Trombina/metabolismo , Biomimética , Dicroísmo Circular , Colágenos Fibrilares/metabolismo , Humanos , Interações Hidrofóbicas e Hidrofílicas , Microscopia de Força Atômica , Modelos Moleculares , Peptídeos/síntese química , Trombina/químicaRESUMO
The gut microbiome is a malleable microbial community that can remodel in response to various factors, including diet, and contribute to the development of several chronic diseases, including atherosclerosis. We devised an in vitro screening protocol of the mouse gut microbiome to discover molecules that can selectively modify bacterial growth. This approach was used to identify cyclic D,L-α-peptides that remodeled the Western diet (WD) gut microbiome toward the low-fat-diet microbiome state. Daily oral administration of the peptides in WD-fed LDLr-/- mice reduced plasma total cholesterol levels and atherosclerotic plaques. Depletion of the microbiome with antibiotics abrogated these effects. Peptide treatment reprogrammed the microbiome transcriptome, suppressed the production of pro-inflammatory cytokines (including interleukin-6, tumor necrosis factor-α and interleukin-1ß), rebalanced levels of short-chain fatty acids and bile acids, improved gut barrier integrity and increased intestinal T regulatory cells. Directed chemical manipulation provides an additional tool for deciphering the chemical biology of the gut microbiome and might advance microbiome-targeted therapeutics.
Assuntos
Aterosclerose/microbiologia , Microbioma Gastrointestinal , Animais , Antibacterianos/farmacologia , Anti-Inflamatórios/farmacologia , Aterosclerose/sangue , Bactérias/efeitos dos fármacos , Bactérias/crescimento & desenvolvimento , Biomarcadores/metabolismo , Colesterol/sangue , Dieta Ocidental , Comportamento Alimentar , Feminino , Microbioma Gastrointestinal/genética , Regulação da Expressão Gênica/efeitos dos fármacos , Interações Hospedeiro-Patógeno/efeitos dos fármacos , Interações Hospedeiro-Patógeno/genética , Fatores Imunológicos/farmacologia , Camundongos Endogâmicos C57BL , Modelos Biológicos , Peptídeos Cíclicos/química , Peptídeos Cíclicos/farmacologia , Receptores de LDL/metabolismo , Proteínas de Junções Íntimas/metabolismo , Transcrição GênicaRESUMO
The alpha(V) integrins are key receptors involved in mediating cell migration and angiogenesis. In age-related macular degeneration (AMD) and diabetic retinopathy, angiogenesis plays a critical role in the loss of vision. These ocular vasculopathies might be treatable with a suitable alpha(V) antagonist, and an oral drug would offer a distinct advantage over current therapies. (3,S,beta,S)-1,2,3,4-Tetrahydro-beta-[[1-[1-oxo-3-(1,5,6,7-tetrahydro-1,8-naphthyridin-2-yl)propyl]-4-piperidinyl]methyl]-3-quinolinepropanoic acid (JNJ-26076713) is a potent, orally bioavailable, nonpeptide alpha(V) antagonist derived from the arginine-glycine-asparagine binding motif in the matrix protein ligands (e.g., vitronectin). This compound inhibits alpha(V)beta(3) and alpha(V)beta(5) binding to vitronectin in the low nanomolar range, it has excellent selectivity over integrins alpha(IIb)beta(3) and alpha(5)beta(1), and it prevents adhesion to human, rat, and mouse endothelial cells. JNJ-26076713 blocks cell migration induced by vascular endothelial growth factor, fibroblast growth factor (FGF), and serum, and angiogenesis induced by FGF in the chick chorioallantoic membrane model. JNJ-26076713 is the first alpha(V) antagonist reported to inhibit retinal neovascularization in an oxygen-induced model of retinopathy of prematurity after oral administration. In diabetic rats, orally administered JNJ-26076713 markedly inhibits retinal vascular permeability, a key early event in diabetic macular edema and AMD. Given this profile, JNJ-26076713 represents a potential therapeutic candidate for the treatment of age-related macular degeneration, macular edema, and proliferative diabetic retinopathy.
Assuntos
Permeabilidade Capilar/fisiologia , Diabetes Mellitus Experimental/metabolismo , Retinopatia Diabética/metabolismo , Integrina alfaV/metabolismo , Naftiridinas/administração & dosagem , Naftiridinas/farmacocinética , Quinolinas/administração & dosagem , Quinolinas/farmacocinética , Neovascularização Retiniana/metabolismo , Administração Oral , Inibidores da Angiogênese/administração & dosagem , Inibidores da Angiogênese/química , Inibidores da Angiogênese/farmacocinética , Animais , Disponibilidade Biológica , Permeabilidade Capilar/efeitos dos fármacos , Linhagem Celular , Embrião de Galinha , Diabetes Mellitus Experimental/tratamento farmacológico , Retinopatia Diabética/tratamento farmacológico , Modelos Animais de Doenças , Feminino , Humanos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Naftiridinas/química , Gravidez , Quinolinas/química , Ratos , Ratos Long-Evans , Ratos Sprague-Dawley , Neovascularização Retiniana/tratamento farmacológicoRESUMO
The marketed drug topiramate ( 1) is a moderate inhibitor of carbonic anhydrase-II (CA-II) ( K i or K d = 0.3-0.6 microM), whereas sulfamide cognate 2 is a comparatively weak inhibitor ( K i or K d = 25-650 microM). From an X-ray cocrystal structure of 2.CA-II, Winum et al. ( J. Med. Chem. 2006, 49, 7024) proposed that an adverse steric interaction between the C8 methyl group in 2 and Ala-65 of CA-II is responsible for the diminished CA-II inhibitory potency of 2. We performed a straightforward test of this Ala-65 effect by synthesizing and examining ligand 3, which lacks the offending (pro- S or C8) methyl substituent in 2. We also prepared and evaluated related sulfamides 5, 7, and 9. In a CA-II inhibition assay (4-nitrophenyl acetate), the K i for 3 was approximately 300 microM, indicating very weak inhibition, close to that for 2 (4NPA, K i = 340 microM). In a CA-II binding assay (ThermoFluor), the K d for 3 was >57 microM, indicating very weak binding, lower than the affinity of 2 ( K d = 25 microM). Our results draw into question the proposed steric interaction between the C8 methyl of 2 and Ala-65 of CA-II.
Assuntos
Anidrase Carbônica II/antagonistas & inibidores , Inibidores da Anidrase Carbônica/farmacologia , Frutose/análogos & derivados , Inibidores da Anidrase Carbônica/química , Cristalografia por Raios X , Frutose/química , Frutose/farmacologia , Cinética , Espectroscopia de Ressonância Magnética , TopiramatoRESUMO
We have developed a novel series of potent and selective factor Xa inhibitors that employ a key 7-fluoroindazolyl moiety. The 7-fluoro group on the indazole scaffold replaces the carbonyl group of an amide that is found in previously reported factor Xa inhibitors. The structure of a factor Xa cocrystal containing 7-fluoroindazole 51a showed the 7-fluoro atom hydrogen-bonding with the N-H of Gly216 (2.9 A) in the peptide backbone. Thus, the 7-fluoroindazolyl moiety not only occupied the same space as the carbonyl group of an amide found in prior factor Xa inhibitors but also maintained a hydrogen bond interaction with the protein's beta-sheet domain. The structure-activity relationship for this series was consistent with this finding, as the factor Xa inhibitory potencies were about 60-fold greater (DeltaDelta G approximately 2.4 kcal/mol) for the 7-fluoroindazoles 25a and 25c versus the corresponding indazoles 25b and 25d. Highly convergent synthesis of these factor Xa inhibitors is also described.
Assuntos
Inibidores do Fator Xa , Indazóis/síntese química , Inibidores de Serina Proteinase/síntese química , Células CACO-2 , Permeabilidade da Membrana Celular , Cristalografia por Raios X , Fator Xa/química , Humanos , Ligação de Hidrogênio , Técnicas In Vitro , Indazóis/química , Indazóis/farmacologia , Microssomos Hepáticos/enzimologia , Modelos Moleculares , Conformação Proteica , Inibidores de Serina Proteinase/química , Inibidores de Serina Proteinase/farmacologia , Relação Estrutura-Atividade , TermodinâmicaRESUMO
The dysregulation of arginine vasopressin (AVP) release and activation of vasopressin V(1A) and V(2) receptors may play a role in disease. The in vitro and in vivo pharmacology of RWJ-676070, a potent, balanced antagonist of both the V(1A) and V(2) receptors is described. RWJ-676070 binding and intracellular functional antagonist activity was characterized using cells expressing V(1A), V(1B) or V(2) receptors. Its inhibition of V(1A) receptor-mediated contraction of vascular rings and platelet aggregation was determined. V(2) receptor-medated aquaresis was determined in rats, dogs and monkeys. V(1A) receptor-mediated inhibitory activity was assessed in vivo in a vasopressin-induced hypertension model and in normotensive rats and in two hypertensive rat models. RWJ-676070 inhibited AVP binding to human V(1A) and V(2) receptors (Ki=1 and 14 nM, respectively). RWJ-676070 inhibited V(1A) receptor-induced intracellular calcium mobilization and V(2) receptor-induced cAMP accumulation with Ki values of 14 nM and 13 nM, respectively. The compound was slightly less potent against rat V(1A) receptors. RWJ-676070 inhibited V(1A) receptor-mediated vasoconstriction in rat and dog vascular rings and AVP-induced human platelet aggregation. Dose dependent aquaresis was demonstrated in rats, dogs and monkeys following oral administration. RWJ-676070 inhibited AVP-induced hypertension in rats but had no effect on arterial pressure in normotensive and spontaneously hypertensive rats but did decrease arterial pressure in Dahl, salt-sensitive hypertensive rats. RWJ-676070 is a new, potent antagonist of V(1A) and V(2) receptors that may be useful for treatment of diseases benefiting from balanced inhibition of both V(1A) and V(2) receptors.
Assuntos
Antagonistas dos Receptores de Hormônios Antidiuréticos , Benzazepinas/farmacologia , Compostos de Espiro/farmacologia , Animais , Pressão Sanguínea/efeitos dos fármacos , Cães , Relação Dose-Resposta a Droga , Feminino , Frequência Cardíaca/efeitos dos fármacos , Humanos , Hipertensão/tratamento farmacológico , Técnicas In Vitro , Macaca fascicularis , Masculino , Agregação Plaquetária/efeitos dos fármacos , Ratos , Ratos Endogâmicos SHR , Vasoconstrição , Vasopressinas/farmacologiaRESUMO
Triple reuptake inhibitors, which block the serotonin transporter (SERT), norepinephrine transporter (NET) and dopamine transporter (DAT) in the central nervous system have been described as therapeutic alternatives for classical selective serotonin reuptake inhibitors, with advantages due to their multiple mechanisms of action. JNJ-7925476 (trans-6-(4-ethynylphenyl)-1,2,3,5,6,10b-hexahydropyrrolo[2,1-a]isoquinoline) is a selective and potent inhibitor of the SERT, NET, and DAT (K(i)=0.9, 17 and 5.2 nM, respectively). Following subcutaneous dosing in rat, JNJ-7925476 was rapidly absorbed into the plasma, and drug concentrations in the brain tracked with those in the plasma but were 7-fold higher. The ED(50) values for JNJ-7925476 occupancy of the SERT, NET, and DAT in rat brain were 0.18, 0.09 and 2.4 mg/kg, respectively. JNJ-7925476 (0.1-10 mg/kg, s.c.) rapidly induced a robust, dose-dependent increase in extracellular serotonin, dopamine, and norepinephrine levels in rat cerebral cortex. The compound also showed potent antidepressant-like activity in the mouse tail suspension test (ED(50)=0.3 mg/kg, i.p.). These results demonstrate that JNJ-7925476 is a triple reuptake inhibitor with in-vivo efficacy in biochemical and behavioral models of depression.
Assuntos
Isoquinolinas/farmacologia , Inibidores da Captação de Neurotransmissores/farmacologia , Pirróis/farmacologia , Animais , Área Sob a Curva , Autorradiografia , Barreira Hematoencefálica/efeitos dos fármacos , Química Encefálica/efeitos dos fármacos , Linhagem Celular Tumoral , Córtex Cerebral/efeitos dos fármacos , Córtex Cerebral/metabolismo , Proteínas da Membrana Plasmática de Transporte de Dopamina/metabolismo , Elevação dos Membros Posteriores , Humanos , Isoquinolinas/química , Isoquinolinas/farmacocinética , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Microdiálise , Atividade Motora/efeitos dos fármacos , Inibidores da Captação de Neurotransmissores/química , Inibidores da Captação de Neurotransmissores/farmacocinética , Pirróis/química , Pirróis/farmacocinética , Ratos , Ratos Sprague-Dawley , Proteínas da Membrana Plasmática de Transporte de Serotonina/metabolismo , EstereoisomerismoRESUMO
2-Cyano-6-fluorophenylacetamide was explored as a novel P2 scaffold in the design of thrombin inhibitors. Optimization around this structural motif culminated in 14, which is a potent thrombin inhibitor (K(i)=1.2nM) that exhibits robust efficacy in canine anticoagulation and thrombosis models upon oral administration.
Assuntos
Acetamidas , Motivos de Aminoácidos , Anticoagulantes/administração & dosagem , Desenho de Fármacos , Nitrilas , Trombina/antagonistas & inibidores , Trombose/tratamento farmacológico , Acetamidas/síntese química , Acetamidas/farmacocinética , Acetamidas/uso terapêutico , Administração Oral , Animais , Anticoagulantes/síntese química , Anticoagulantes/farmacocinética , Sítios de Ligação , Modelos Animais de Doenças , Cães , Relação Dose-Resposta a Droga , Haplorrinos , Humanos , Ligação de Hidrogênio , Modelos Químicos , Nitrilas/síntese química , Nitrilas/farmacocinética , Nitrilas/uso terapêutico , Ratos , Relação Estrutura-AtividadeRESUMO
We have explored a series of spirocyclic piperidine amide derivatives (5) as tryptase inhibitors. Thus, 4 (JNJ-27390467) was identified as a potent, selective tryptase inhibitor with oral efficacy in two animal models of airway inflammation (sheep and guinea pig asthma models). An X-ray co-crystal structure of 4 x tryptase revealed a hydrophobic pocket in the enzyme's active site, which is induced by the phenylethynyl group and is comprised of amino acid residues from two different monomers of the tetrameric protein.
Assuntos
Asma/tratamento farmacológico , Hipersensibilidade Respiratória/tratamento farmacológico , Inibidores de Serina Proteinase/farmacologia , Compostos de Espiro/síntese química , Compostos de Espiro/farmacologia , Triptases/antagonistas & inibidores , Administração Oral , Animais , Disponibilidade Biológica , Cromatografia Líquida de Alta Pressão , Cristalografia por Raios X , Inibidores das Enzimas do Citocromo P-450 , Modelos Animais de Doenças , Cães , Cobaias , Humanos , Microssomos Hepáticos/efeitos dos fármacos , Microssomos Hepáticos/enzimologia , Estrutura Molecular , Ratos , Inibidores de Serina Proteinase/síntese química , Inibidores de Serina Proteinase/farmacocinética , Ovinos , Espectrometria de Massas por Ionização por Electrospray , Compostos de Espiro/farmacocinética , Tripsina/metabolismo , Triptases/metabolismoRESUMO
This article reviews the scientific literature on the application of alpha-ketoheterocycles to the discovery of potent enzyme inhibitors. The alpha-ketoheterocycle functionality provides a moderately electrophilic ketone carbonyl with 'tunable' reactivity, as well as a structural template for introducing new interactions in the enzyme active-site cleft. This type of moiety has served an important role in the design of active-site-directed inhibitors of diverse serine and cysteine proteases, and of fatty acid amide hydrolase (FAAH). Potent inhibitors have been identified for, inter alia, elastase, thrombin, factor Xa, tryptase, chymase, cathepsin K, cathepsin S, and FAAH. For example, 6e is an orally active inhibitor of human neutrophil elastase that entered human clinical studies, 52h is an orally bioavailable inhibitor of human chymase, and 82m is a FAAH inhibitor with in vivo endocannabinoid-enhancing activity.
Assuntos
Amidoidrolases/antagonistas & inibidores , Compostos Heterocíclicos/farmacologia , Inibidores de Proteases/química , Inibidores Enzimáticos/química , Compostos Heterocíclicos/farmacocinética , Humanos , Cetonas/farmacologiaRESUMO
A series of beta-carboxamido-phosphon(in)ic acids (2) was identified as a new structural motif for obtaining potent inhibitors of human mast cell chymase. For example, 1-naphthyl derivative 5f had an IC50 value of 29 nM and (E)-styryl derivative 6g had an IC50 value of 3.5 nM. An X-ray structure for 5f.chymase revealed key interactions within the enzyme active site. Compound 5f was selective for inhibiting chymase versus eight serine proteases. Compound 6h was orally bioavailable in rats (F=39%), and orally efficacious in a hamster model of inflammation.
Assuntos
Amidas/síntese química , Anti-Inflamatórios não Esteroides/síntese química , Quimases/antagonistas & inibidores , Mastócitos/enzimologia , Organofosfonatos/síntese química , Ácidos Fosfínicos/síntese química , Administração Oral , Amidas/química , Amidas/farmacologia , Animais , Anti-Inflamatórios não Esteroides/química , Anti-Inflamatórios não Esteroides/farmacologia , Sítios de Ligação , Disponibilidade Biológica , Catepsina G , Catepsinas/antagonistas & inibidores , Cricetinae , Cristalografia por Raios X , Humanos , Modelos Moleculares , Naftalenos/síntese química , Naftalenos/química , Naftalenos/farmacologia , Organofosfonatos/química , Organofosfonatos/farmacologia , Ácidos Fosfínicos/química , Ácidos Fosfínicos/farmacologia , Ratos , Serina Endopeptidases , Estereoisomerismo , Relação Estrutura-AtividadeRESUMO
Various 4-phenylpiperidine-benzoxazin-3-ones were synthesized and biologically evaluated as urotensin-II (U-II) receptor antagonists. Compound 12i was identified from in vitro evaluation as a low nanomolar antagonist against both rat and human U-II receptors. This compound showed in vivo efficacy in reversing the ear-flush response induced by U-II in rats.
Assuntos
Benzoxazinas/síntese química , Piperidinas/síntese química , Receptores Acoplados a Proteínas G/antagonistas & inibidores , Urotensinas/metabolismo , Animais , Benzoxazinas/farmacologia , Células CHO , Cricetinae , Cricetulus , Humanos , Piperidinas/farmacologia , Ratos , Receptores Acoplados a Proteínas G/fisiologia , Relação Estrutura-Atividade , Urotensinas/antagonistas & inibidores , Urotensinas/fisiologiaRESUMO
We have continued to explore spirobenzazepines as vasopressin receptor antagonists to follow up on RWJ-339489 (2), which had advanced into preclinical development. Further structural modifications were pursued to find a suitable backup compound for human clinical studies. Thus, we identified carboxylic acid derivative 3 (RWJ-676070; JNJ-17158063) as a potent, balanced vasopressin V(1a)/V(2) receptor antagonist with favorable properties for clinical development. Compound 3 is currently undergoing human clinical investigation.
Assuntos
Antagonistas dos Receptores de Hormônios Antidiuréticos , Benzazepinas/química , Compostos de Espiro/química , Animais , Anti-Hipertensivos/administração & dosagem , Anti-Hipertensivos/química , Anti-Hipertensivos/metabolismo , Anti-Hipertensivos/farmacocinética , Benzazepinas/administração & dosagem , Benzazepinas/farmacocinética , Benzazepinas/farmacologia , Avaliação Pré-Clínica de Medicamentos , Feminino , Humanos , Masculino , Ratos , Ratos Long-Evans , Receptores de Vasopressinas/metabolismo , Receptores de Vasopressinas/fisiologia , Compostos de Espiro/administração & dosagem , Compostos de Espiro/metabolismo , Compostos de Espiro/farmacocinética , Compostos de Espiro/farmacologia , Vasopressinas/metabolismoRESUMO
There is great interest in developing new modes of therapy for atherosclerosis to treat coronary heart disease and stroke, particularly ones that involve modulation of high-density lipoproteins (HDLs). Here, we describe a new supramolecular chemotype for altering HDL morphology and function. Guided by rational design and SAR-driven peptide sequence enumerations, we have synthesized and determined the HDL remodeling activities of over 80 cyclic d,l-α-peptides. We have identified a few distinct sequence motifs that are effective in vitro in remodeling human and mouse plasma HDLs to increase the concentration of lipid-poor pre-beta HDLs, which are key initial acceptors of cholesterol in the reverse cholesterol transport (RCT) process, and concomitantly promote cholesterol efflux from macrophage cells. Functional assays with various control peptides, such as scrambled sequences, linear and enantiomeric cyclic peptide variants, and backbone-modified structures that limit peptide self-assembly, provide strong support for the supramolecular mode of action. Importantly, when the lead cyclic peptide c[wLwReQeR] was administered to mice (ip), it also promoted the formation of small, lipid-poor HDLs in vivo, displayed good plasma half-life (â¼6 h), did not appear to have adverse side effects, and exerted potent anti-inflammatory effects in an acute in vivo inflammation assay. Given that previously reported HDL remodeling peptides have been based on α-helical apoA-I mimetic architectures, the present study, involving a new structural class, represents a promising step toward new potential therapeutics to combat atherosclerosis.
RESUMO
This paper examines the relative effectiveness of bioisosteric sulfamate and sulfamide derivatives for inhibition of human carbonic anhydrase-II (CA-II) by using a direct binding assay based on the ThermoFluor method (Matulis et al. Biochemistry 2005, 44, 5258). Compounds 1-10, which represent five cognate sulfamate/sulfamide pairs, were studied by ThermoFluor to obtain binding affinities (K(a) values). The corresponding dissociation constants, K(d), provide an independent measure of CA-II activity relative to commonly used K(i) values from enzyme kinetics studies. There was a sizable difference in potency between the sulfamates and sulfamides, with the sulfamides being much less potent, by factors ranging from 25 (7/8) to 1,200 (3/4). These results are consistent with our recent report that sulfamides tend to be much weaker inhibitors of CA-II than their corresponding sulfamates (Maryanoff et al. J. Med. Chem. 2005, 48, 1941). Additionally, for arylsulfamides 10-12 the K(d) values determined by ThermoFluor and the K(i) values determined from enzyme kinetics are consistent. It appears that the sulfamide group is less suitable than the sulfamate group for obtaining potent inhibition of CA-II.