RESUMO
Multitarget ligands (MTLs) have emerged as an interesting alternative for addressing complex multifactorial pathologies such as neurodegenerative diseases. However, a common challenge associated with these compounds is often their high molecular weight and low solubility, which becomes a hurdle when trying to permeate over the blood-brain barrier (BBB). In this study, we have designed two new MTLs that modulate three pharmacological targets simultaneously (tau, beta-amyloid and TAR DNA-binding protein 43). To enhance their brain penetration, we have formulated organic polymeric nanoparticles using poly(lactic-co-glycolic acid). The characterization of the formulations, evaluation of their permeability through an in vitro BBB model, and assessment of their activity on disease-representative cellular models, such as Alzheimer's disease and amyotrophic lateral sclerosis, have been conducted. The results demonstrate the potential of the new MTLs and their nanoparticle encapsulation for the treatment of neurodegenerative diseases.
Assuntos
Barreira Hematoencefálica , Doenças Neurodegenerativas , Permeabilidade , Copolímero de Ácido Poliláctico e Ácido Poliglicólico , Copolímero de Ácido Poliláctico e Ácido Poliglicólico/química , Ligantes , Humanos , Barreira Hematoencefálica/metabolismo , Barreira Hematoencefálica/efeitos dos fármacos , Doenças Neurodegenerativas/tratamento farmacológico , Doenças Neurodegenerativas/metabolismo , Nanopartículas/química , Desenho de Fármacos , Composição de Medicamentos , Peptídeos beta-Amiloides/metabolismo , Animais , Proteínas tau/metabolismoRESUMO
AIMS: Multiple sclerosis (MS) is a chronic neurological disease that currently lacks effective curative treatments. There is a need to find effective therapies, especially to reverse the progressive demyelination and neuronal damage. Oligodendrocytes form the myelin sheath around axons in the central nervous system (CNS) and oligodendrocyte precursor cells (OPCs) undergo mechanisms that enable spontaneously the partial repair of damaged lesions. The aim of this study was to discover small molecules with potential effects in demyelinating diseases, including (re)myelinating properties. METHODS: Recently, it has been shown how LRRK2 inhibition promotes oligodendrogliogenesis and therefore an efficient repair or myelin damaged lesions. Here we explored small molecules inhibiting LRRK2 as potential enhancers of primary OPCs proliferation and differentiation, and their potential impact on the clinical score of experimental autoimmune encephalomyelitys (EAE) mice, a validated model of the most frequent clinical form of MS, relapsing-remitting MS. RESULTS: One of the LRRK2 inhibitors presented in this study promoted the proliferation and differentiation of OPC primary cultures. When tested in the EAE murine model of MS, it exerted a statistically significant reduction of the clinical burden of the animals, and histological evidence revealed how the treated animals presented a reduced lesion area in the spinal cord. CONCLUSIONS: For the first time, a small molecule with LRRK2 inhibition properties presented (re)myelinating properties in primary OPCs cultures and potentially in the in vivo murine model. This study provides an in vivo proof of concept for a LRRK2 inhibitor, confirming its potential for the treatment of MS.
Assuntos
Encefalomielite Autoimune Experimental , Esclerose Múltipla , Células Precursoras de Oligodendrócitos , Camundongos , Animais , Encefalomielite Autoimune Experimental/patologia , Células Precursoras de Oligodendrócitos/patologia , Modelos Animais de Doenças , Bainha de Mielina/patologia , Oligodendroglia/patologia , Diferenciação Celular , Benzotiazóis/farmacologia , Benzotiazóis/uso terapêutico , Camundongos Endogâmicos C57BLRESUMO
Ebola virus (EBOV) is a single-strand RNA virus belonging to the Filoviridae family, which has been associated to most Ebola virus disease outbreaks to date, including the West African and the North Kivu epidemics between 2013 and 2022. This unprecedented health emergency prompted the search for effective medical countermeasures. Following up on the carbazole hit identified in our previous studies, we synthetized a new series of compounds, which demonstrated to prevent EBOV infection in cells by acting as virus entry inhibitors. The in vitro inhibitory activity was evaluated through the screening against surrogate models based on viral pseudotypes and further confirmed using replicative EBOV. Docking and molecular dynamics simulations joined to saturation transfer difference-nuclear magnetic resonance (STD-NMR) and mutagenesis experiments to elucidate the biological target of the most potent compounds. Finally, in vitro metabolic stability and in vivo pharmacokinetic studies were performed to confirm their therapeutic potential.
Assuntos
Ebolavirus , Doença pelo Vírus Ebola , Humanos , Simulação de Dinâmica Molecular , Mutagênese , Replicação ViralRESUMO
Fragile X syndrome (FXS) is caused by the loss of function of Fragile X mental retardation protein (FMRP). FXS is one of the leading monogenic causes of intellectual disability (ID) and autism. Although it is caused by the failure of a single gene, FMRP that functions as an RNA binding protein affects a large number of genes secondarily. All these genes represent hundreds of potential targets and different mechanisms that account for multiple pathological features, thereby hampering the search for effective treatments. In this scenario, it seems desirable to reorient therapies toward more general approaches. Neuronal calcium sensor 1 (NCS-1), through its interaction with the guanine-exchange factor Ric8a, regulates the number of synapses and the probability of the release of a neurotransmitter, the two neuronal features that are altered in FXS and other neurodevelopmental disorders. Inhibitors of the NCS-1/Ric8a complex have been shown to be effective in restoring abnormally high synapse numbers as well as improving associative learning in FMRP mutant flies. Here, we demonstrate that phenothiazine FD44, an NCS-1/Ric8a inhibitor, has strong inhibition ability in situ and sufficient bioavailability in the mouse brain. More importantly, administration of FD44 to two different FXS mouse models restores well-known FXS phenotypes, such as hyperactivity, associative learning, aggressive behavior, stereotype, or impaired social approach. It has been suggested that dopamine (DA) may play a relevant role in the behavior and in neurodevelopmental disorders in general. We have measured DA and its metabolites in different brain regions, finding a higher metabolic rate in the limbic area, which is also restored with FD44 treatment. Therefore, in addition to confirming that the NCS-1/Ric8a complex is an excellent therapeutic target, we demonstrate the rescue effect of its inhibitor on the behavior of cognitive and autistic FXS mice and show DA metabolism as a FXS biochemical disease marker.
RESUMO
Multitarget directed ligands (MTDLs) are arising as promising tools to tackle complex diseases. The main goal of this work is to create powerful modulating agents for neurodegenerative disorders. To achieve this aim, we have combined fragments that inhibit key protein kinases involved in the main pathomolecular pathways of Alzheimer's disease (AD) such as tau aggregation, neuroinflammation and decreased neurogenesis, whilst looking for a third action in beta-secretase (BACE1), responsible of ß-amyloid production. We obtained well-balanced MTDLs with in vitro activity in three different relevant targets and efficacy in two cellular models of AD. Furthermore, computational studies confirmed how these compounds accommodate adequately into the long and rather narrow BACE1 catalytic site. Finally, we employed in situ click chemistry using BACE1 as protein template as a versatile synthetic tool that allowed us to obtain further MTDLs.
Assuntos
Doença de Alzheimer/tratamento farmacológico , Secretases da Proteína Precursora do Amiloide/antagonistas & inibidores , Ácido Aspártico Endopeptidases/antagonistas & inibidores , Inibidores Enzimáticos/farmacologia , Fármacos Neuroprotetores/farmacologia , Triazóis/farmacologia , Doença de Alzheimer/metabolismo , Secretases da Proteína Precursora do Amiloide/metabolismo , Peptídeos beta-Amiloides/antagonistas & inibidores , Peptídeos beta-Amiloides/metabolismo , Ácido Aspártico Endopeptidases/metabolismo , Linhagem Celular , Inibidores Enzimáticos/síntese química , Inibidores Enzimáticos/química , Humanos , Ligantes , Estrutura Molecular , Fármacos Neuroprotetores/síntese química , Fármacos Neuroprotetores/química , Triazóis/síntese química , Triazóis/químicaRESUMO
Despite the efforts to develop new treatments against Ebola virus (EBOV) there is currently no antiviral drug licensed to treat patients with Ebola virus disease (EVD). Therefore, there is still an urgent need to find new drugs to fight against EBOV. In order to do this, a virtual screening was done on the druggable interaction between the EBOV glycoprotein (GP) and the host receptor NPC1 with a subsequent selection of compounds for further validation. This screening led to the identification of new small organic molecules with potent inhibitory action against EBOV infection using lentiviral EBOV-GP-pseudotype viruses. Moreover, some of these compounds have shown their ability to interfere with the intracellular cholesterol transport receptor NPC1 using an ELISA-based assay. These preliminary results pave the way to hit to lead optimization programs that lead to successful candidates.
Assuntos
Antivirais/farmacologia , Descoberta de Drogas/métodos , Proteína C1 de Niemann-Pick/metabolismo , Domínios e Motivos de Interação entre Proteínas/efeitos dos fármacos , Proteínas do Envelope Viral/metabolismo , Internalização do Vírus/efeitos dos fármacos , Animais , Antivirais/isolamento & purificação , Chlorocebus aethiops , Células HEK293 , Células HeLa , Doença pelo Vírus Ebola/tratamento farmacológico , Humanos , Células VeroRESUMO
A previous phenotypic screening campaign led to the identification of a quinazoline derivative with promising in vitro activity against Schistosoma mansoni. Follow-up studies of the antischistosomal potential of this candidate are presented here. The in vivo studies in a S. mansoni mouse model show a significant reduction of total worms and a complete disappearance of immature eggs when administered concomitantly with praziquantel in comparison with the administration of praziquantel alone. This fact is of utmost importance because eggs are responsible for the pathology and transmission of the disease. Subsequently, the chemical optimisation of the structure in order to improve the metabolic stability of the parent compound was carried out leading to derivatives with improved drug-like properties. Additionally, the putative target of this new class of antischistosomal compounds was envisaged by using computational tools and the binding mode to the target enzyme, aldose reductase, was proposed.
Assuntos
Aldeído Redutase/antagonistas & inibidores , Inibidores Enzimáticos/química , Inibidores Enzimáticos/farmacologia , Quinazolinas/química , Quinazolinas/farmacologia , Schistosoma mansoni/efeitos dos fármacos , Aldeído Redutase/metabolismo , Animais , Anti-Helmínticos , Relação Dose-Resposta a Droga , Inibidores Enzimáticos/síntese química , Masculino , Camundongos , Modelos Moleculares , Estrutura Molecular , Quinazolinas/síntese química , Schistosoma mansoni/enzimologia , Relação Estrutura-AtividadeRESUMO
We report the evaluation of 265 compounds from a PDE-focused library for their antischistosomal activity, assessed in vitro using Schistosoma mansoni. Of the tested compounds, 171 (64%) displayed selective in vitro activity, with 16 causing worm hypermotility/spastic contractions and 41 inducing various degrees of worm killing at 100⯵M, with the surviving worms displaying sluggish movement, worm unpairing and complete absence of eggs. The compounds that did not affect worm viability (nâ¯=â¯72) induced a complete cessation of ovipositing. 82% of the compounds had an impact on male worms whereas female worms were barely affected. In vivo evaluation in S. mansoni-infected mice with the in vitro 'hit' NPD-0274â¯at 20â¯mg/kg/day orally for 5 days resulted in worm burden reductions of 29% and intestinal tissue egg load reduction of 35% at 10 days post-treatment. Combination of praziquantel (PZQ) at 10â¯mg/kg/day for 5 days with NPD-0274 or NPD-0298 resulted in significantly higher worm killing than PZQ alone, as well as a reduction in intestinal tissue egg load, disappearance of immature eggs and an increase in the number of dead eggs.
Assuntos
Anti-Helmínticos/farmacologia , Imidazóis/farmacologia , Schistosoma mansoni/efeitos dos fármacos , Bibliotecas de Moléculas Pequenas , 3',5'-AMP Cíclico Fosfodiesterases/antagonistas & inibidores , Animais , Anti-Helmínticos/química , Descoberta de Drogas , Fibroblastos/efeitos dos fármacos , Ensaios de Triagem em Larga Escala , Humanos , Imidazóis/química , Masculino , Camundongos , Contagem de Ovos de Parasitas , Praziquantel/farmacologiaRESUMO
More than 100 years after being first described, Chagas disease remains endemic in 21 Latin American countries and has spread to other continents. Indeed, this disease, which is caused by the protozoan parasite Trypanosoma cruzi, is no longer just a problem for the American continents but has become a global health threat. Current therapies, i.e., nifurtimox and benznidazole (Bz), are far from being adequate, due to their undesirable effects and their lack of efficacy in the chronic phases of the disease. In this work, we present an in-depth phenotypic evaluation in T. cruzi of a new class of imidazole compounds, which were discovered in a previous phenotypic screen against different trypanosomatids and were designed as potential inhibitors of cAMP phosphodiesterases (PDEs). The confirmation of several activities similar or superior to that of Bz prompted a synthesis program of hit optimization and extended structure-activity relationship aimed at improving drug-like properties such as aqueous solubility, which resulted in additional hits with 50% inhibitory concentration (IC50) values similar to that of Bz. The cellular effects of one representative hit, compound 9, on bloodstream trypomastigotes were further investigated. Transmission electron microscopy revealed cellular changes, after just 2 h of incubation with the IC50 concentration, that were consistent with induced autophagy and osmotic stress, mechanisms previously linked to cAMP signaling. Compound 9 induced highly significant increases in both cellular and medium cAMP levels, confirming that inhibition of T. cruzi PDE(s) is part of its mechanism of action. The potent and selective activity of this imidazole-based PDE inhibitor class against T. cruzi constitutes a successful repurposing of research into inhibitors of mammalian PDEs.
Assuntos
3',5'-AMP Cíclico Fosfodiesterases/antagonistas & inibidores , Antiparasitários/farmacologia , Doença de Chagas/tratamento farmacológico , Imidazóis/farmacologia , Trypanosoma cruzi/efeitos dos fármacos , Animais , Autofagia/efeitos dos fármacos , Células Cultivadas , Descoberta de Drogas , Imidazóis/síntese química , Camundongos , Testes de Sensibilidade Parasitária , Relação Estrutura-AtividadeRESUMO
The Cu-catalyzed silylation of terminal and internal alkynes bearing a 2-pyridyl sulfonyl group (SO2Py) at the propargylic position affords a breadth of vinyl silanes in good yields and with excellent regio- and stereocontrol under mild conditions. The directing SO2Py group is essential in terms of reaction efficiency and chemoselectivity. Importantly, this group also provides the ability to reverse the regiochemical outcome of the reaction, opening the access to either regioisomer without modification of the starting substrate by virtue of an in situ base-promoted alkyne to allene equilibration which takes place prior to the silylcupration process. Furthermore, removal of the directing SO2Py allows for further elaboration of the silylation products. In particular, a one-pot tandem alkyne silylation/allylic substitution sequence, in which both steps are catalyzed by the same Cu species, opens up a new approach for the access to either formal hydrosilylation regioisomer of unsymmetrical aliphatic-substituted internal alkynes from propargyl sulfones.
RESUMO
A practical Pd-catalyzed ortho-olefination of enantioenriched N-(SO2Py)-protected aryl-alanine and norephedrine derivatives with electron-deficient alkenes has been developed using N-fluoro-2,4,6-trimethylpyridinium triflate as the terminal oxidant. The reaction occurs efficiently with excellent monosubstitution selectivity and without loss of enantiopurity. This cross-coupling proved to be broad in scope, tolerating a variety of steric and electronic changes to both coupling partners. Removal of the directing group under mild conditions provides access to optically active tetrahydroisoquinoline-3-carboxylic acid derivatives (Tics) with good diastereocontrol and with very small erosion of enantiomeric purity.
RESUMO
By using DABCO·(SO(2))(2), DABSO, as a solid bench-stable SO(2)-equivalent, the palladium-catalysed aminosulfonylation of aryl-, alkenyl- and heteroaryl halides has been achieved. N,N-Dialkylhydrazines are employed as the N-nucleophiles and provide N-aminosulfonamides as the products in good to excellent yields. The reactions are operationally simple to perform, requiring only a slight excess of SO(2) (1.2-2.2 equiv.), and tolerate a variety of substituents on the halide coupling partner. Variation of the hydrazine component is also demonstrated. The use of N,N-dibenzylhydrazine as the N-nucleophile delivers N-aminosulfonamide products that can be converted into the corresponding primary sulfonamides using a high-yielding, telescoped, deprotection sequence. The ability to employ hydrazine·SO(2) complexes as both the N-nucleophile and SO(2) source is also illustrated.
Assuntos
Alcenos/química , Halogênios/química , Paládio/química , Ácidos Sulfônicos/química , Catálise , Estrutura MolecularRESUMO
The Pd(II)-catalyzed direct coupling of arene C-H bonds with organoboron reagents assisted by the 2-pyridylsulfinyl group is reported. Methylboronic acid and arylboronic acid neopentyl esters proved to be efficient coupling partners, furnishing methylated arenes and biaryl products in moderate to good yields. The 2-pyridylsulfinyl group can be easily removed to provide the free biaryls. The essential role of the 2-pyridyl unit in stabilizing the cyclopalladation complex was demonstrated by X-ray diffraction analysis of the palladacycle intermediate.
RESUMO
The easily installed and removed N-(2-pyridyl)sulfonyl group exerts complete C2 regiocontrol over the Pd(II)-catalysed C-H alkenylation of indoles and pyrroles, affording the corresponding products in good isolated yields (typically > or = 70 %). A remarkable feature of this catalyst system is that it tolerates a wide variety of substituted alkenes, including conjugated electron-deficient alkenes, styrenes and 1,3-dienes, as well as conjugated 1,1- and 1,2-disubstituted olefins. The final reductive desulfonylation affords the C2-substituted, free-NH indoles and pyrroles in good yield. This N-(2-pyridyl)sulfonyl-directing strategy has also been extended to the development of a protocol for the intermolecular, dehydrogenative homocoupling of indoles, providing 2,2'-biindoles. Mechanistic work based upon reactions with isotopically labelled starting materials and competitive kinetic studies of electronically varied substrates suggests a chelation-assisted electrophilic aromatic substitution palladation mechanism.