Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 24
Filtrar
Más filtros










Base de datos
Intervalo de año de publicación
1.
PLoS Pathog ; 17(4): e1009477, 2021 04.
Artículo en Inglés | MEDLINE | ID: mdl-33857257

RESUMEN

The lack of efficient methods to control the major diseases of crops most important to agriculture leads to huge economic losses and seriously threatens global food security. Many of the most important microbial plant pathogens, including bacteria, fungi, and oomycetes, secrete necrosis- and ethylene-inducing peptide 1 (Nep1)-like proteins (NLPs), which critically contribute to the virulence and spread of the disease. NLPs are cytotoxic to eudicot plants, as they disturb the plant plasma membrane by binding to specific plant membrane sphingolipid receptors. Their pivotal role in plant infection and broad taxonomic distribution makes NLPs a promising target for the development of novel phytopharmaceutical compounds. To identify compounds that bind to NLPs from the oomycetes Pythium aphanidermatum and Phytophthora parasitica, a library of 587 small molecules, most of which are commercially unavailable, was screened by surface plasmon resonance. Importantly, compounds that exhibited the highest affinity to NLPs were also found to inhibit NLP-mediated necrosis in tobacco leaves and Phytophthora infestans growth on potato leaves. Saturation transfer difference-nuclear magnetic resonance and molecular modelling of the most promising compound, anthranilic acid derivative, confirmed stable binding to the NLP protein, which resulted in decreased necrotic activity and reduced ion leakage from tobacco leaves. We, therefore, confirmed that NLPs are an appealing target for the development of novel phytopharmaceutical agents and strategies, which aim to directly interfere with the function of these major microbial virulence factors. The compounds identified in this study represent lead structures for further optimization and antimicrobial product development.


Asunto(s)
Phytophthora/patogenicidad , Enfermedades de las Plantas/prevención & control , Pythium/patogenicidad , Solanum tuberosum/genética , Simulación de Dinámica Molecular , Necrosis , Phytophthora/genética , Enfermedades de las Plantas/parasitología , Hojas de la Planta/genética , Hojas de la Planta/parasitología , Pythium/genética , Solanum tuberosum/parasitología , Resonancia por Plasmón de Superficie , Nicotiana/genética , Nicotiana/parasitología
2.
Int J Pharm ; 564: 106-116, 2019 Jun 10.
Artículo en Inglés | MEDLINE | ID: mdl-30999044

RESUMEN

Crystalline bulking agent in lyophilized biopharmaceutical formulations provides an elegant lyophilized cake structure and allows aggressive primary drying conditions. The interplay between amorphous and crystalline state of excipients heavily influence the stability of lyophilized biological products and should be carefully evaluated in the formulation and process development phase. This study focuses on: (1) elucidating the influence of formulation and lyophilization process variables on the formation of different states of mannitol and (2) its impact on model monoclonal antibody stability when compared to sucrose. The main aim of the present research work was to study the influence of different mannitol to sucrose ratios and monoclonal antibody concentrations on mannitol physical form established during lyophilization. In addition, also the effect of process variables on mannitol hemihydrate (MHH) formation was under investigation. Thermal analysis and powder X-ray diffraction results revealed that the ratio between sucrose and mannitol and mAb concentration have a decisive impact on mannitol crystallization. Namely, increasing amount of mannitol and monoclonal antibody resulted in decreasing formation of MHH. From the process parameters investigated, a higher secondary drying temperature has the biggest impact on the complete dehydration of MHH. Specifically, higher secondary drying temperature reflected in complete dehydration of MHH. Annealing temperature was shown to affect the MHH content in the final product, wherein the higher annealing temperature was preferential for formation of anhydrous mannitol. Temperature stress stability study revealed that the most important parameter influencing monoclonal antibody stability is the ratio of protein to sucrose. Contrary to widespread assumption, we did not detect any impact of MHH on the stability of the investigated monoclonal antibody.


Asunto(s)
Anticuerpos Monoclonales/química , Inmunoglobulina G/química , Manitol/química , Sacarosa/química , Estabilidad de Medicamentos , Liofilización , Estabilidad Proteica , Temperatura
3.
Eur J Pharm Sci ; 122: 292-302, 2018 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-30006178

RESUMEN

Freeze-drying is the method of choice to dry formulations with biopharmaceutical drugs, to enhance protein stability. This is usually done below the glass transition temperature of maximally freeze-concentrated solutions (Tg'), to avoid protein aggregation, preserve protein activity, and obtain pharmaceutically 'elegant' cakes. Unfortunately, this is a lengthy and energy-consuming process. However, it was recently shown that drying above Tg' or even above the collapse temperature (Tc) is not necessarily detrimental for stability of biopharmaceuticals, and hence provides an attractive option for freeze-drying cycle optimisation. The goal of the present study was to optimise the freeze-drying cycle for a model IgG monoclonal antibody (20 mg/mL) in sucrose and sucrose/glycine formulations, by reducing primary drying time. To study the impact of shelf temperature (Ts) and chamber pressure on product temperature (Tp), one conventional and five aggressive cycles were tested. Aggressive conditions during primary drying were achieved by increasing Ts from -20 °C (conventional cycle) to 30 °C, with chamber pressure set to 0.1 mbar, 0.2 mbar or 0.3 mbar. These combinations of Ts and chamber pressure resulted in Tp well above Tg', and in some cases, even above Tc, without causing macrocollapse. Other critical quality attributes of the products were also within the expected ranges, such as reconstitution time and residual water content. Physical stability was tested using size exclusion chromatography, dynamic light scattering, and micro-flow imaging. All of the lyophilised samples were exposed to stress and the intended storage conditions, with no impacts on the product seen. These data show that implementation of aggressive conditions for the investigated formulations is possible and can significantly contribute to the reduction of primary drying times by up to 54% (from 48 to 22 h) in comparison to conventional freeze-drying.


Asunto(s)
Composición de Medicamentos/métodos , Anticuerpos Monoclonales/química , Excipientes/química , Liofilización/métodos , Glicina/química , Inmunoglobulina G/química , Sacarosa/química
4.
J Med Chem ; 61(1): 119-139, 2018 01 11.
Artículo en Inglés | MEDLINE | ID: mdl-29227101

RESUMEN

The enzymatic activity of butyrylcholinesterase (BChE) in the brain increases with the progression of Alzheimer's disease, thus classifying BChE as a promising drug target in advanced Alzheimer's disease. We used structure-based drug discovery approaches to develop potent, selective, and reversible human BChE inhibitors. The most potent, compound 3, had a picomolar inhibition constant versus BChE due to strong cation-π interactions, as revealed by the solved crystal structure of its complex with human BChE. Additionally, compound 3 inhibits BChE ex vivo and is noncytotoxic. In vitro pharmacokinetic experiments show that compound 3 is highly protein bound, highly permeable, and metabolically stable. Finally, compound 3 crosses the blood-brain barrier, and it improves memory, cognitive functions, and learning abilities of mice in a scopolamine model of dementia. Compound 3 is thus a promising advanced lead compound for the development of drugs for alleviating symptoms of cholinergic hypofunction in patients with advanced Alzheimer's disease.


Asunto(s)
Butirilcolinesterasa/metabolismo , Inhibidores de la Colinesterasa/química , Inhibidores de la Colinesterasa/farmacología , Diseño de Fármacos , Animales , Butirilcolinesterasa/química , Inhibidores de la Colinesterasa/metabolismo , Inhibidores de la Colinesterasa/farmacocinética , Cristalografía por Rayos X , Femenino , Humanos , Cinética , Masculino , Ratones , Modelos Moleculares , Unión Proteica , Conformación Proteica , Ratas , Seguridad , Termodinámica , Distribución Tisular
5.
Sci Rep ; 7(1): 11459, 2017 09 13.
Artículo en Inglés | MEDLINE | ID: mdl-28904354

RESUMEN

Cathepsin X is a cysteine peptidase involved in the progression of cancer and neurodegenerative diseases. Targeting this enzyme with selective inhibitors opens a new possibility for intervention in several therapeutic areas. In this study triazole-based reversible and selective inhibitors of cathepsin X have been identified. Their selectivity and binding is enhanced when the 2,3-dihydrobenzo[b][1,4]dioxine moiety is present as the R1 substituent. Of a series of selected triazole-benzodioxine derivatives, compound 22 is the most potent inhibitor of cathepsin X carboxypeptidase activity (Ki = 2.45 ± 0.05 µM) with at least 100-fold greater selectivity in comparison to cathepsin B or other related cysteine peptidases. Compound 22 is not cytotoxic to prostate cancer cells PC-3 or pheochromocytoma PC-12 cells at concentrations up to 10 µM. It significantly inhibits the migration of tumor cells and increases the outgrowth of neurites, both processes being under the control of cathepsin X carboxypeptidase activity. Compound 22 and other characterized triazole-based inhibitors thus possess a great potential for further development resulting in several in vivo applications.


Asunto(s)
Catepsina K/antagonistas & inhibidores , Inhibidores de Cisteína Proteinasa/farmacología , Descubrimiento de Drogas , Animales , Catepsina K/química , Inhibidores de Cisteína Proteinasa/química , Descubrimiento de Drogas/métodos , Cinética , Espectroscopía de Resonancia Magnética , Estructura Molecular , Proyección Neuronal/efectos de los fármacos , Células PC12 , Unión Proteica , Ratas , Bibliotecas de Moléculas Pequeñas , Relación Estructura-Actividad
6.
Bioorg Med Chem Lett ; 27(4): 944-949, 2017 02 15.
Artículo en Inglés | MEDLINE | ID: mdl-28077258

RESUMEN

We report on the successful application of ProBiS-CHARMMing web server in the discovery of new inhibitors of MurA, an enzyme that catalyzes the first committed cytoplasmic step of bacterial peptidoglycan synthesis. The available crystal structures of Escherichia coli MurA in the Protein Data Bank have binding sites whose small volume does not permit the docking of drug-like molecules. To prepare the binding site for docking, the ProBiS-CHARMMing web server was used to simulate the induced-fit effect upon ligand binding to MurA, resulting in a larger, more holo-like binding site. The docking of a filtered ZINC compound library to this enlarged binding site was then performed and resulted in three compounds with promising inhibitory potencies against MurA. Compound 1 displayed significant inhibitory potency with IC50 value of 1µM. All three compounds have novel chemical structures, which could be used for further optimization of small-molecule MurA inhibitors.


Asunto(s)
Transferasas Alquil y Aril/antagonistas & inhibidores , Inhibidores Enzimáticos/farmacología , Transferasas Alquil y Aril/química , Transferasas Alquil y Aril/metabolismo , Secuencia de Carbohidratos , Descubrimiento de Drogas , Inhibidores Enzimáticos/química , Simulación del Acoplamiento Molecular , Peptidoglicano/metabolismo
7.
Bioorg Med Chem ; 25(2): 633-645, 2017 01 15.
Artículo en Inglés | MEDLINE | ID: mdl-27908752

RESUMEN

In the brains of patients with Alzheimer's disease, the enzymatic activities of butyrylcholinesterase (BChE) and monoamine oxidase B (MAO-B) are increased. While BChE is a viable therapeutic target for alleviation of symptoms caused by cholinergic hypofunction, MAO-B is a potential therapeutic target for prevention of neurodegeneration in Alzheimer's disease. Starting with piperidine-based selective human (h)BChE inhibitors and propargylamine-based MAO inhibitors, we have designed, synthesized and biochemically evaluated a series of N-propargylpiperidines. All of these compounds inhibited hBChE with good selectivity over the related enzyme, acetylcholinesterase, and crossed the blood-brain barrier in a parallel artificial membrane permeation assay. The crystal structure of one of the inhibitors (compound 3) in complex with hBChE revealed its binding mode. Three compounds (4, 5, 6) showed concomitant inhibition of MAO-B. Additionally, the most potent hBChE inhibitor 7 and dual BChE and MAO-B inhibitor 6 were non-cytotoxic and protected neuronal SH-SY5Y cells from toxic amyloid ß-peptide species.


Asunto(s)
Enfermedad de Alzheimer/tratamiento farmacológico , Inhibidores de la Colinesterasa/farmacología , Inhibidores de la Monoaminooxidasa/farmacología , Naftalenos/farmacología , Piperidinas/farmacología , Sulfonamidas/farmacología , Péptidos beta-Amiloides/antagonistas & inhibidores , Péptidos beta-Amiloides/metabolismo , Péptidos beta-Amiloides/farmacología , Butirilcolinesterasa/metabolismo , Muerte Celular/efectos de los fármacos , Línea Celular , Inhibidores de la Colinesterasa/síntesis química , Inhibidores de la Colinesterasa/química , Relación Dosis-Respuesta a Droga , Humanos , Estructura Molecular , Monoaminooxidasa/metabolismo , Inhibidores de la Monoaminooxidasa/síntesis química , Inhibidores de la Monoaminooxidasa/química , Naftalenos/síntesis química , Naftalenos/química , Fragmentos de Péptidos/antagonistas & inhibidores , Fragmentos de Péptidos/metabolismo , Fragmentos de Péptidos/farmacología , Piperidinas/síntesis química , Piperidinas/química , Relación Estructura-Actividad , Sulfonamidas/síntesis química , Sulfonamidas/química
8.
Sci Rep ; 6: 39495, 2016 12 21.
Artículo en Inglés | MEDLINE | ID: mdl-28000737

RESUMEN

Alzheimer's disease (AD) is characterized by severe basal forebrain cholinergic deficit, which results in progressive and chronic deterioration of memory and cognitive functions. Similar to acetylcholinesterase, butyrylcholinesterase (BChE) contributes to the termination of cholinergic neurotransmission. Its enzymatic activity increases with the disease progression, thus classifying BChE as a viable therapeutic target in advanced AD. Potent, selective and reversible human BChE inhibitors were developed. The solved crystal structure of human BChE in complex with the most potent inhibitor reveals its binding mode and provides the molecular basis of its low nanomolar potency. Additionally, this compound is noncytotoxic and has neuroprotective properties. Furthermore, this inhibitor moderately crosses the blood-brain barrier and improves memory, cognitive functions and learning abilities of mice in a model of the cholinergic deficit that characterizes AD, without producing acute cholinergic adverse effects. Our study provides an advanced lead compound for developing drugs for alleviating symptoms caused by cholinergic hypofunction in advanced AD.


Asunto(s)
Enfermedad de Alzheimer/tratamiento farmacológico , Inhibidores de la Colinesterasa/farmacología , Diseño de Fármacos , Animales , Barrera Hematoencefálica , Encéfalo/patología , Butirilcolinesterasa , Dominio Catalítico , Cromatografía Líquida de Alta Presión , Progresión de la Enfermedad , Evaluación Preclínica de Medicamentos , Femenino , Humanos , Aprendizaje , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Conformación Proteica , Ratas , Ratas Wistar
9.
Angew Chem Int Ed Engl ; 55(19): 5745-8, 2016 05 04.
Artículo en Inglés | MEDLINE | ID: mdl-27037901

RESUMEN

Elevated expression of the immunoproteasome has been associated with autoimmune diseases, inflammatory diseases, and various types of cancer. Selective inhibitors of the immunoproteasome are not only scarce, but also almost entirely restricted to peptide-based compounds. Herein, we describe nonpeptidic reversible inhibitors that selectively block the chymotrypsin-like (ß5i) subunit of the human immunoproteasome in the low micromolar range. The most potent of the reversibly acting compounds were then converted into covalent, irreversible, nonpeptidic inhibitors that retained selectivity for the ß5i subunit. In addition, these inhibitors discriminate between the immunoproteasome and the constitutive proteasome in cell-based assays. Along with their lack of cytotoxicity, these data point to these nonpeptidic compounds being suitable for further investigation as ß5i-selective probes for possible application in noncancer diseases related to the immunoproteasome.


Asunto(s)
Complejo de la Endopetidasa Proteasomal/metabolismo , Inhibidores de Proteasoma/metabolismo , Línea Celular , Supervivencia Celular/efectos de los fármacos , Células HeLa , Humanos , Concentración 50 Inhibidora , Cinética , Simulación del Acoplamiento Molecular , Oligopéptidos/química , Oligopéptidos/metabolismo , Oligopéptidos/toxicidad , Complejo de la Endopetidasa Proteasomal/química , Inhibidores de Proteasoma/química , Inhibidores de Proteasoma/toxicidad , Subunidades de Proteína/antagonistas & inhibidores , Subunidades de Proteína/metabolismo , Relación Estructura-Actividad
10.
J Chem Inf Model ; 55(8): 1521-8, 2015 Aug 24.
Artículo en Inglés | MEDLINE | ID: mdl-26158767

RESUMEN

We developed LiSiCA (ligand similarity using clique algorithm)--ligand-based virtual screening software that uses a fast maximum clique algorithm to find two- and three-dimensional similarities between pairs of molecules and applied it to the discovery of novel potent butyrylcholinesterase inhibitors. LiSiCA, which runs in parallel on multiple processor cores, was successfully tested on the Database of Useful Decoys-Enhanced, to evaluate its ability to discriminate active molecules from decoys. We then applied LiSiCA for the discovery of novel inhibitors of human butyrylcholinesterase, a promising anti-Alzheimer target, using a known inhibitor as the reference compound. We demonstrated that LiSiCA is capable of finding potent nanomolar inhibitors, whose scaffolds differed from the reference compound, thus proving its ability for scaffold hopping and usefulness in drug discovery.


Asunto(s)
Butirilcolinesterasa/metabolismo , Inhibidores de la Colinesterasa/química , Inhibidores de la Colinesterasa/farmacología , Descubrimiento de Drogas/métodos , Programas Informáticos , Algoritmos , Enfermedad de Alzheimer/tratamiento farmacológico , Enfermedad de Alzheimer/enzimología , Humanos , Ligandos , Modelos Moleculares
11.
Arch Pharm (Weinheim) ; 348(8): 556-63, 2015 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-26032855

RESUMEN

Alzheimer's disease (AD) is a fatal and complex neurodegenerative disorder for which effective treatment remains the unmet challenge. Using donepezil as a starting point, we aimed to develop novel potential anti-AD agents with a multidirectional biological profile. We designed the target compounds as dual binding site acetylcholinesterase inhibitors, where the N-benzylamine pharmacophore is responsible for interactions with the catalytic anionic site of the enzyme. The heteroaromatic fragment responsible for interactions with the peripheral anionic site was modified and three different heterocycles were introduced: isoindoline, isoindolin-1-one, and saccharine. Based on the results of the pharmacological evaluation, we identified compound 8b with a saccharine moiety as the most potent and selective human acetylcholinesterase inhibitor (IC50 = 33 nM) and beta amyloid aggregation inhibitor. It acts as a non-competitive acetylcholinesterase inhibitor and is able to cross the blood-brain barrier in vitro. We believe that compound 8b represents an important lead compound for further development as potential anti-AD agent.


Asunto(s)
Enfermedad de Alzheimer/tratamiento farmacológico , Péptidos beta-Amiloides/metabolismo , Bencilaminas/síntesis química , Bencilaminas/farmacología , Inhibidores de la Colinesterasa/síntesis química , Inhibidores de la Colinesterasa/farmacología , Diseño de Fármacos , Compuestos Heterocíclicos/síntesis química , Compuestos Heterocíclicos/farmacología , Fragmentos de Péptidos/metabolismo , Acetilcolinesterasa/química , Acetilcolinesterasa/metabolismo , Enfermedad de Alzheimer/diagnóstico , Enfermedad de Alzheimer/enzimología , Péptidos beta-Amiloides/química , Sitios de Unión , Unión Competitiva , Barrera Hematoencefálica/metabolismo , Butirilcolinesterasa/metabolismo , Permeabilidad Capilar , Dominio Catalítico , Inhibidores de la Colinesterasa/metabolismo , Proteínas Ligadas a GPI/antagonistas & inhibidores , Proteínas Ligadas a GPI/química , Proteínas Ligadas a GPI/metabolismo , Cinética , Ligandos , Simulación del Acoplamiento Molecular , Terapia Molecular Dirigida , Fragmentos de Péptidos/química , Agregación Patológica de Proteínas , Unión Proteica , Conformación Proteica , Sacarina/análogos & derivados , Sacarina/síntesis química , Sacarina/farmacología , Relación Estructura-Actividad
12.
Bioorg Med Chem ; 23(15): 4442-4452, 2015 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-26116179

RESUMEN

Tremendous efforts have been dedicated to the development of effective therapeutics against Alzheimer's disease, which represents the most common debilitating neurodegenerative disease. Multifunctional agents are molecules designed to have simultaneous effects on different pathological processes. Such compounds represent an emerging strategy for the development of effective treatments against Alzheimer's disease. Here, we report on the synthesis and biological evaluation of a series of nitroxoline-based analogs that were designed by merging the scaffold of 8-hydroxyquinoline with that of a known selective butyrylcholinesterase inhibitor that has promising anti-Alzheimer properties. Most strikingly, compound 8g inhibits self-induced aggregation of the amyloid beta peptide (Aß1-42), inhibits with sub-micromolar potency butyrylcholinesterase (IC50=215 nM), and also selectively complexes Cu(2+). Our study thus designates this compound as a promising multifunctional agent for therapeutic treatment of Alzheimer's disease. The crystal structure of human butyrylcholinesterase in complex with compound 8g is also solved, which suggests ways to further optimize compounds featuring the 8-hydroxyquinoline scaffold.


Asunto(s)
Inhibidores de la Colinesterasa/química , Nitroquinolinas/química , Enfermedad de Alzheimer/tratamiento farmacológico , Péptidos beta-Amiloides/química , Péptidos beta-Amiloides/metabolismo , Sitios de Unión , Butirilcolinesterasa/química , Butirilcolinesterasa/metabolismo , Quelantes/química , Quelantes/metabolismo , Inhibidores de la Colinesterasa/síntesis química , Inhibidores de la Colinesterasa/uso terapéutico , Cristalografía por Rayos X , Diseño de Fármacos , Humanos , Metales/química , Metales/metabolismo , Simulación del Acoplamiento Molecular , Nitroquinolinas/síntesis química , Nitroquinolinas/uso terapéutico , Fragmentos de Péptidos/química , Fragmentos de Péptidos/metabolismo , Unión Proteica , Estructura Terciaria de Proteína , Espectrofotometría Ultravioleta
13.
Bioorg Med Chem ; 23(10): 2445-57, 2015 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-25868744

RESUMEN

Due to the complex nature of Alzheimer's disease, multi-target-directed ligand approaches are one of the most promising strategies in the search for effective treatments. Acetylcholinesterase, butyrylcholinesterase and ß-amyloid are the predominant biological targets in the search for new anti-Alzheimer's agents. Our aim was to combine both anticholinesterase and ß-amyloid anti-aggregation activities in one molecule, and to determine the therapeutic potential in vivo. We designed and synthesized 28 new compounds as derivatives of donepezil that contain the N-benzylpiperidine moiety combined with the phthalimide or indole moieties. Most of these test compounds showed micromolar activities against cholinesterases and aggregation of ß-amyloid, combined with positive results in blood-brain barrier permeability assays. The most promising compound 23 (2-(8-(1-(3-chlorobenzyl)piperidin-4-ylamino)octyl)isoindoline-1,3-dione) is an inhibitor of butyrylcholinesterase (IC50=0.72 µM) that has ß-amyloid anti-aggregation activity (72.5% inhibition at 10 µM) and can cross the blood-brain barrier. Moreover, in an animal model of memory impairment induced by scopolamine, the activity of 23 was comparable to that of donepezil. The selected compound 23 is an excellent lead structure in the further search for new anti-Alzheimer's agents.


Asunto(s)
Acetilcolinesterasa/química , Enfermedad de Alzheimer/tratamiento farmacológico , Amnesia/tratamiento farmacológico , Butirilcolinesterasa/química , Inhibidores de la Colinesterasa/síntesis química , Fármacos Neuroprotectores/síntesis química , Piperidinas/síntesis química , Enfermedad de Alzheimer/metabolismo , Enfermedad de Alzheimer/patología , Amnesia/inducido químicamente , Amnesia/metabolismo , Amnesia/patología , Péptidos beta-Amiloides , Animales , Barrera Hematoencefálica/efectos de los fármacos , Inhibidores de la Colinesterasa/farmacología , Modelos Animales de Enfermedad , Donepezilo , Humanos , Indanos/farmacología , Indoles/química , Masculino , Memoria/efectos de los fármacos , Ratones , Modelos Moleculares , Fármacos Neuroprotectores/farmacología , Ftalimidas/química , Piperidinas/farmacología , Agregado de Proteínas/efectos de los fármacos , Escopolamina , Relación Estructura-Actividad
14.
Bioorg Med Chem ; 23(7): 1629-37, 2015 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-25707322

RESUMEN

Alzheimer's disease is a fatal neurodegenerative disorder with a complex etiology. Because the available therapy brings limited benefits, the effective treatment for Alzheimer's disease remains the unmet challenge. Our aim was to develop a new series of donepezil-based compounds endowed with inhibitory properties against cholinesterases and ß-amyloid aggregation. We designed the target compounds as dual binding site acetylcholinesterase inhibitors with N-benzylamine moiety interacting with the catalytic site of the enzyme and an isoindoline-1,3-dione fragment interacting with the peripheral anionic site of the enzyme. The results of pharmacological evaluation lead us to identify a compound 3b as the most potent and selective human acetylcholinesterase inhibitor (hAChE IC50=0.361µM). Kinetic studies revealed that 3b inhibited acetylcholinesterase in non-competitive mode. The result of the parallel artificial membrane permeability assay for the blood-brain barrier indicated that the compound 3b would be able to cross the blood-brain barrier and reach its biological targets in the central nervous system. The selected compound 3b represents a potential lead structure for further development of anti-Alzheimer's agents.


Asunto(s)
Enfermedad de Alzheimer/enzimología , Inhibidores de la Colinesterasa/síntesis química , Sistemas de Liberación de Medicamentos/métodos , Diseño de Fármacos , Indoles/síntesis química , Enfermedad de Alzheimer/tratamiento farmacológico , Animales , Inhibidores de la Colinesterasa/administración & dosificación , Colinesterasas/química , Colinesterasas/metabolismo , Evaluación Preclínica de Medicamentos/métodos , Caballos , Humanos , Indoles/administración & dosificación , Estructura Secundaria de Proteína
15.
Eur J Med Chem ; 92: 738-49, 2015 Mar 06.
Artículo en Inglés | MEDLINE | ID: mdl-25621991

RESUMEN

The presented study describes the synthesis, pharmacological evaluation (AChE and BuChE inhibition, beta amyloid anti-aggregation effect and neuroprotective effect), molecular modeling and crystallographic studies of a novel series of isoindoline-1,3-dione derivatives. The target compounds were designed as dual binding site acetylcholinesterase inhibitors with an arylalkylamine moiety binding at the catalytic site of the enzyme and connected via an alkyl chain to a heterocyclic fragment, capable of binding at the peripheral anionic site of AChE. Among these molecules, compound 15b was found to be the most potent and selective AChE inhibitor (IC50EeAChE = 0.034 µM). Moreover, compound 13b in addition to AChE inhibition (IC50 EeAChE = 0.219 µM) possesses additional properties, such as the ability to inhibit Aß aggregation (65.96% at 10 µM) and a neuroprotective effect against Aß toxicity at 1 and 3 µM. Compound 13b emerges as a promising multi-target ligand for the further development of the therapy for age-related neurodegenerative disorders.


Asunto(s)
Acetilcolinesterasa/metabolismo , Péptidos beta-Amiloides/antagonistas & inhibidores , Bencilaminas/farmacología , Inhibidores de la Colinesterasa/farmacología , Fármacos Neuroprotectores/farmacología , Ftalimidas/farmacología , Agregado de Proteínas/efectos de los fármacos , Agregación Patológica de Proteínas/tratamiento farmacológico , Péptidos beta-Amiloides/metabolismo , Bencilaminas/síntesis química , Bencilaminas/química , Línea Celular Tumoral , Inhibidores de la Colinesterasa/síntesis química , Inhibidores de la Colinesterasa/química , Relación Dosis-Respuesta a Droga , Humanos , Modelos Moleculares , Estructura Molecular , Fármacos Neuroprotectores/síntesis química , Fármacos Neuroprotectores/química , Ftalimidas/síntesis química , Ftalimidas/química , Relación Estructura-Actividad
16.
Molecules ; 19(11): 19209-19, 2014 Nov 19.
Artículo en Inglés | MEDLINE | ID: mdl-25415480

RESUMEN

We describe a ligand-based approach towards compounds with more specific targeting for Burkitt's lymphoma. Using three-dimensional ligand-based similarity searches and a previously described hit compound, we have identified six compounds that are chemically different but with similar spatial conformations. Biological evaluation revealed that one compound has better growth inhibition and improved selectivity towards Burkitt's lymphoma cells than the query compound. However, initial mechanism-of-action studies show a different target profile in comparison with the previous hit compound, which does not involve the inhibition of the proteasome or the NFκB pathway. The data from this study provide a solid basis for further efforts in the search for selective agents against Burkitt's lymphoma.


Asunto(s)
Linfoma de Burkitt/tratamiento farmacológico , Bibliotecas de Moléculas Pequeñas/farmacología , Linfoma de Burkitt/metabolismo , Línea Celular Tumoral , Humanos , Ligandos , FN-kappa B/metabolismo , Complejo de la Endopetidasa Proteasomal/metabolismo
17.
J Med Chem ; 57(19): 8167-79, 2014 Oct 09.
Artículo en Inglés | MEDLINE | ID: mdl-25226236

RESUMEN

Butyrylcholinesterase (BChE) is regarded as a promising drug target as its levels and activity significantly increase in the late stages of Alzheimer's disease. To discover novel BChE inhibitors, we used a hierarchical virtual screening protocol followed by biochemical evaluation of 40 highest scoring hit compounds. Three of the compounds identified showed significant inhibitory activities against BChE. The most potent, compound 1 (IC50 = 21.3 nM), was resynthesized and resolved into its pure enantiomers. A high degree of stereoselective activity was revealed, and a dissociation constant of 2.7 nM was determined for the most potent stereoisomer (+)-1. The crystal structure of human BChE in complex with compound (+)-1 was solved, revealing the binding mode and providing clues for potential optimization. Additionally, compound 1 inhibited amyloid ß(1-42) peptide self-induced aggregation into fibrils (by 61.7% at 10 µM) and protected cultured SH-SY5Y cells against amyloid-ß-induced toxicity. These data suggest that compound 1 represents a promising candidate for hit-to-lead follow-up in the drug-discovery process against Alzheimer's disease.


Asunto(s)
Butirilcolinesterasa/química , Inhibidores de la Colinesterasa/síntesis química , Péptidos beta-Amiloides/química , Animales , Línea Celular Tumoral , Inhibidores de la Colinesterasa/química , Inhibidores de la Colinesterasa/farmacología , Cromatografía Líquida de Alta Presión , Cristalización , Descubrimiento de Drogas , Humanos , Ratones , Simulación del Acoplamiento Molecular , Fragmentos de Péptidos/química , Agregado de Proteínas , Estereoisomerismo
18.
Eur J Med Chem ; 70: 393-9, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-24177366

RESUMEN

Toll-like receptor 4 (TLR4) in complex with its accessory protein MD-2 represents an emerging target for the treatment of severe sepsis and neuropathic pain. We performed structure-based and ligand-based virtual screening targeting the TLR4-MD-2 interface. Three in silico hit compounds showed promising TLR4 antagonistic activities with micromolar IC50 values. These compounds also suppressed cytokine secretion by human peripheral blood mononuclear cells. The specific affinity of the most potent hit was confirmed by surface plasmon resonance direct-binding experiments. The results of our study represent a very promising starting point for the development of potent small-molecule antagonists of TLR4.


Asunto(s)
Ensayos Analíticos de Alto Rendimiento , Bibliotecas de Moléculas Pequeñas/farmacología , Receptor Toll-Like 4/antagonistas & inhibidores , Citocinas/antagonistas & inhibidores , Citocinas/metabolismo , Relación Dosis-Respuesta a Droga , Células HEK293 , Humanos , Leucocitos Mononucleares/efectos de los fármacos , Leucocitos Mononucleares/metabolismo , Ligandos , Modelos Moleculares , Estructura Molecular , Bibliotecas de Moléculas Pequeñas/química , Solubilidad , Relación Estructura-Actividad , Resonancia por Plasmón de Superficie
19.
Biochimie ; 95(6): 1120-6, 2013 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-23270797

RESUMEN

Murein peptide ligase (Mpl) is an enzyme found in Gram-negative bacteria. It catalyses the addition of tripeptide L-Ala-γ-D-Glu-meso-diaminopimelate to nucleotide precursor UDP-N-acetylmuramic acid during the recycling of peptidoglycan. Although not essential, this enzyme represents an interesting target for antibacterial compounds through the synthesis of alternate substrates whose incorporation into peptidoglycan might be deleterious for the bacterial cell. Therefore, we have synthesised 10 tripeptides L-Ala-γ-D-Glu-Xaa in which Xaa represents amino acids different from diaminopimelic acid. Tripeptide with Xaa = ε-D-Lys proved to be an excellent substrate of Escherichia coli Mpl in vitro. Tripeptides with Xaa = p-amino- or p-nitro-L-phenylalanine were poor substrates, while tripeptides with Xaa = D- or L-2-aminopimelate, DL-2-aminoheptanoic acid, L-Glu, L-norleucine, L-norvaline, L-2-aminobutyric acid or L-Ala were not substrates at all. Although a good Mpl substrate, the D-Lys-containing tripeptide was devoid of antibacterial activity against E. coli, presumably owing to poor uptake.


Asunto(s)
Proteínas de Escherichia coli/metabolismo , Oligopéptidos/síntesis química , Oligopéptidos/metabolismo , Péptido Sintasas/metabolismo , Cromatografía Líquida de Alta Presión , Oligopéptidos/química , Especificidad por Sustrato
20.
Chem Biol Interact ; 202(1-3): 204-9, 2013 Feb 25.
Artículo en Inglés | MEDLINE | ID: mdl-23261716

RESUMEN

The imbalance in expression of the human aldo-keto reductases AKR1C1-AKR1C3 is related to different hormone dependent and independent cancers and some other diseases. The AKR1C1-3 enzymes thus represent emerging targets for the development of new drugs. Currently, various enzymatic assays are used in the search for AKR1C inhibitors, and consequently the results of different research groups are not necessarily comparable. During our recent search for AKR1C inhibitors, we found a cyclopentanol derivative (2-(4-chlorobenzylidene)cyclopentanol, CBCP-ol) and its respective cyclopentanone counterpart (2-(4-chlorobenzylidene)cyclopentanone, CBCP-one) that acted as AKR1C substrates. We determined the kinetic parameters KM, kcat and kcat/KM for oxidation of CBCP-ol and reduction of CBCP-one by AKR1C enzymes in the presence of NAD(+)/NADP(+) and NADH/NADPH, respectively. The catalytic efficiencies for the oxidation of CBCP-ol in the presence of NAD(+) or NADP(+) were in general higher when compared to the catalytic efficiencies for reduction of CBCP-one in the presence of NADH or NADPH. When NADPH was used, as compared to NADH, the reductions of CBCP-one by AKR1C1, AKR1C2 and AKR1C3 were 14-, 51- and 31-fold more efficient, respectively. When comparing to oxidations of the well-known artificial substrates, 1-acenaphthenol and S-tetralol, we observed similar catalytic efficiencies as for CBCP-ol oxidation with NAD(+) and NADP(+). The comparison of CBCP-one reduction with NADPH to reductions of physiological substrates revealed in general higher efficiencies, except for reduction of 9-cis-retinaldehyde by AKR1C3. This NADPH-dependent reduction of CBCP-one was then used to re-evaluate inhibitory potencies of the known inhibitors of the target AKR1C3 and the anti-target AKR1C2, medroxyprogesterone acetate and ursodeoxycholic acid, respectively, showing Ki constants similar to the reported values. Our data thus confirm that the new enzymatic assays with two cyclopentane substrates CBP-ol and CBP-one, and especially reduction of CBCP-one with NADPH, are appropriate for the evaluation of AKR1C inhibitors.


Asunto(s)
20-Hidroxiesteroide Deshidrogenasas/antagonistas & inhibidores , 20-Hidroxiesteroide Deshidrogenasas/metabolismo , 3-Hidroxiesteroide Deshidrogenasas/antagonistas & inhibidores , 3-Hidroxiesteroide Deshidrogenasas/metabolismo , Pruebas de Enzimas/métodos , Hidroxiprostaglandina Deshidrogenasas/antagonistas & inhibidores , Hidroxiprostaglandina Deshidrogenasas/metabolismo , Oxidorreductasas de Alcohol/metabolismo , Aldehído Reductasa , Miembro C3 de la Familia 1 de las Aldo-Ceto Reductasas , Aldo-Ceto Reductasas , Catálisis , Ciclopentanos/farmacología , Inhibidores Enzimáticos/farmacología , Humanos , Cinética , Acetato de Medroxiprogesterona/farmacología , NAD/metabolismo , NADP/metabolismo , Oxidación-Reducción , Ácido Ursodesoxicólico/farmacología
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA