RESUMO
To date, Alzheimer's disease is the most alarming neurodegenerative disorder worldwide. This illness is multifactorial in nature and cholinesterase inhibitors have been the ones used in clinical treatments. In this context, many of these drugs selectively inhibit the acetylcholinesterase enzyme interacting in both the active site and the peripheric anionic site. Besides, some agents have exhibited extensive benefits being able to co-inhibit butyrylcholinesterase. In this contribution, a strategy previously explored by numerous authors is reported; the synthesis of hybrid cholinesterase inhibitors. This strategy uses a molecule of recognized high inhibitory activity (tacrine) together with a steroidal alkaloid of natural origin using different connectors. The biological assays demonstrated the improvement in the inhibitory activity compared to the alkaloidal precursor, together with the reinforcement of the interactions in multiple sites of the enzymatic cavity. This strategy should be explored and exploited in this area. Docking and molecular dynamic studies were performed to explain enzyme-ligand interactions, assisting a structure-activity relationship analysis.
Assuntos
Alcaloides/farmacologia , Produtos Biológicos/farmacologia , Inibidores da Colinesterase/farmacologia , Desenho de Fármacos , Esteroides/farmacologia , Acetilcolinesterase/metabolismo , Alcaloides/síntese química , Alcaloides/química , Animais , Produtos Biológicos/síntese química , Produtos Biológicos/química , Butirilcolinesterase/metabolismo , Inibidores da Colinesterase/síntese química , Inibidores da Colinesterase/química , Relação Dose-Resposta a Droga , Electrophorus , Cavalos , Estrutura Molecular , Esteroides/síntese química , Esteroides/química , Relação Estrutura-AtividadeRESUMO
Alzheimer's Disease (AD) is a complex neurodegenerative disorder associated in some instances with dyshomeostasis of redox-active metal ions, such as copper and iron. In this work, we investigated whether the conjugation of various aromatic amines would improve the pharmacological efficacy of the iron chelator desferrioxamine (DFO). Conjugates of DFO with aniline (DFOANI), benzosulfanylamide (DFOBAN), 2-naphthalenamine (DFONAF) and 6-quinolinamine (DFOQUN) were obtained and their properties examined. DFOQUN had good chelating activity, promoted a significant increase in the inhibition of ß-amyloid peptide aggregation when compared to DFO, and also inhibited acetylcholinesterase (AChE) activity both in vitro and in vivo (Caenorhabditis elegans). These data indicate that the covalent conjugation of a strong iron chelator to an AChE inhibitor offers a powerful approach for the amelioration of iron-induced neurotoxicity symptoms.
Assuntos
Aminas/farmacologia , Antioxidantes/farmacologia , Caenorhabditis elegans/efeitos dos fármacos , Inibidores da Colinesterase/farmacologia , Desferroxamina/farmacologia , Quelantes de Ferro/farmacologia , Acetilcolinesterase/metabolismo , Aminas/química , Peptídeos beta-Amiloides/antagonistas & inibidores , Peptídeos beta-Amiloides/metabolismo , Animais , Antioxidantes/síntese química , Antioxidantes/química , Compostos de Bifenilo/antagonistas & inibidores , Caenorhabditis elegans/enzimologia , Inibidores da Colinesterase/síntese química , Inibidores da Colinesterase/química , Desferroxamina/química , Humanos , Quelantes de Ferro/síntese química , Quelantes de Ferro/química , Estrutura Molecular , Picratos/antagonistas & inibidores , Agregados Proteicos/efeitos dos fármacosRESUMO
Five new examples of 9,10-chloro(bromo)-7-amine-spiro[chromeno[4,3-b]quinoline-6,1'-cycloalkanes] - in which cycloalkanes = cyclopentane, cyclohexane, and cycloheptane - were synthesized at yields of 42-56%, using a sequential one-pot two-step cyclocondensation reaction of three different scaffolds of 2-aminobenzonitriles and the respective spiro[chroman-2,1'-cycloalkan]-4-ones, and using AlCl3 as the catalyst in a solvent-free method. Subsequently, the five new spirochromeno-quinolines and nine quinolines previously published by us (14 modified tacrine scaffolds) were subjected to AChE and BChE inhibitory activity evaluation. The molecule containing a spirocyclopentane derivative had the highest AChE and BChE inhibitory activity (IC50 = 3.60 and 4.40 µM, respectively), and in general, the non-halogenated compounds were better inhibitors of AChE and BChE than the halogenated molecules. However, the inhibitory potency of compounds 3a-n was weaker than that of tacrine. By molecular docking simulations, it was found that the size of the spirocarbocyclic moieties is inversely proportional to the inhibitory activity of the cholinesterases, probably because an increase in the size of the spirocyclic component sterically hindered the interaction of tacrine derivatives with the active site of tested cholinesterases. The findings obtained here may help in the design and development of new anticholinesterase drugs.
Assuntos
Inibidores da Colinesterase/farmacologia , Colinesterases/metabolismo , Cicloparafinas/farmacologia , Quinolinas/farmacologia , Animais , Inibidores da Colinesterase/síntese química , Inibidores da Colinesterase/química , Cicloparafinas/síntese química , Cicloparafinas/química , Relação Dose-Resposta a Droga , Electrophorus , Cavalos , Simulação de Acoplamento Molecular , Estrutura Molecular , Quinolinas/síntese química , Quinolinas/química , Relação Estrutura-AtividadeRESUMO
A novel series of arylcarbamate-N-acylhydrazones derivatives have been designed and synthesized as potential anti-cholinesterase agents. In vitro studies revealed that these compounds demonstrated selective for butyrylcholinesterase (BuChE) with potent inhibitory activity. The compounds 10a-d, 12b and 12d were the most potent BuChE inhibitors with IC50 values of 0.07-2.07 µM, highlighting the compound 10c (IC50 = 0.07 µM) which showed inhibitory activity 50 times greater than the reference drug donepezil (IC50 = 3.54 µM). The activity data indicates that the position of the carbamate group in the aromatic ring has a greater influence on the inhibitory activity of the derivatives. The enzyme kinetics studies indicate that the compound 10c has a non-competitive inhibition against BuChE with Ki value of 0.097 mM. Molecular modeling studies corroborated the in vitro inhibitory mode of interaction and show that compound 10c is stabilized into hBuChE by strong hydrogen bond interaction with Tyr128, π-π stacking interaction with Trp82 and CHâ¯O interactions with His438, Gly121 and Glu197. Based on these data, compound10cwas identified as low-cost promising candidate for a drug prototype for AD treatment.
Assuntos
Carbamatos/farmacologia , Inibidores da Colinesterase/farmacologia , Desenho de Fármacos , Hidrazonas/farmacologia , Acetilcolinesterase/metabolismo , Animais , Butirilcolinesterase/metabolismo , Carbamatos/síntese química , Carbamatos/química , Inibidores da Colinesterase/síntese química , Inibidores da Colinesterase/química , Relação Dose-Resposta a Droga , Electrophorus , Cavalos , Hidrazonas/síntese química , Hidrazonas/química , Modelos Moleculares , Estrutura Molecular , Relação Estrutura-AtividadeRESUMO
A new series of ten multifunctional Cinnamoyl-N-acylhydrazone-donepezil hybrids was synthesized and evaluated as multifunctional ligands against neurodegenerative diseases. The molecular hybridization approach was based on the combination of 1-benzyl-4-piperidine fragment from the anti-Alzheimer AChE inhibitor donepezil (1) and the cinnamoyl subunit from curcumin (2), a natural product with remarkable antioxidant, neuroprotective and anti-inflammatory properties, using a N-acylhydrazone fragment as a spacer subunit. Compounds 4a and 4d showed moderate inhibitory activity towards AChE with IC50 values of 13.04 and 9.1 µM, respectively. In addition, compound 4a and 4d showed a similar predicted binding mode to that observed for donepezil in the molecular docking studies. On the other hand, compounds 4a and 4c exhibited significant radical scavenging activity, showing the best effects on the DPPH test and also exhibited a significant protective neuronal cell viability exposed to t-BuOOH and against 6-OHDA insult to prevent the oxidative stress in Parkinson's disease. Similarly, compound 4c was capable to prevent the ROS formation, with indirect antioxidant activity increasing intracellular GSH levels and the ability to counteract the neurotoxicity induced by both OAß1-42 and 3-NP. In addition, ADMET in silico prediction indicated that both compounds 4a and 4c did not show relevant toxic effects. Due to their above-mentioned biological properties, compounds 4a and 4c could be explored as lead compounds in search of more effective and low toxic small molecules with multiple neuroprotective effects for neurodegenerative diseases.
Assuntos
Cinamatos/farmacologia , Donepezila/farmacologia , Hidrazonas/farmacologia , Doenças Neurodegenerativas/tratamento farmacológico , Fármacos Neuroprotetores/farmacologia , Acetilcolinesterase/metabolismo , Butirilcolinesterase/metabolismo , Linhagem Celular Tumoral , Inibidores da Colinesterase/síntese química , Inibidores da Colinesterase/metabolismo , Inibidores da Colinesterase/farmacocinética , Inibidores da Colinesterase/farmacologia , Cinamatos/síntese química , Cinamatos/metabolismo , Cinamatos/farmacocinética , Donepezila/síntese química , Donepezila/metabolismo , Donepezila/farmacocinética , Sequestradores de Radicais Livres/síntese química , Sequestradores de Radicais Livres/metabolismo , Sequestradores de Radicais Livres/farmacocinética , Sequestradores de Radicais Livres/farmacologia , Humanos , Hidrazonas/síntese química , Hidrazonas/metabolismo , Hidrazonas/farmacocinética , Ligantes , Simulação de Acoplamento Molecular , Estrutura Molecular , Fármacos Neuroprotetores/síntese química , Fármacos Neuroprotetores/metabolismo , Fármacos Neuroprotetores/farmacocinética , Ligação Proteica , Relação Estrutura-AtividadeRESUMO
Alzheimer's disease (AD) is a neurodegenerative process that compromises cognitive functions. The physiopathology of AD is multifactorial and is mainly supported by the cholinergic and amyloid hypotheses, which allows the identification the fundamental role of some markers, such as the enzymes acetylcholinesterase (AChE) and ß-secretase (BACE-1), and the ß-amyloid peptide (Aß). In this work, we prepared a series of chalcones and 2'-aminochalcones, which were tested against AChE and BACE-1 enzymes and on the aggregation of Aß. All compounds inhibited AChE activity with different potencies. We have found that the majority of chalcones having the amino group are able to inhibit BACE-1, which was not observed for chalcones without this group. The most active compound is the one derived from 2,3-dichlorobenzaldeyde, having an IC50 value of 2.71 µM. A molecular docking study supported this result, showing a good interaction of the amino group with aspartic acid residues of the catalytic diade of BACE-1. Thioflavin-T fluorescence emission is reduced in 30 - 40%, when Aß42 is incubated in the presence of some chalcones under aggregation conditions. In vitro cytotoxicity and in silico prediction of pharmacokinetic properties were also conducted in this study.
Assuntos
Chalconas/farmacologia , Inibidores da Colinesterase/farmacologia , Inibidores de Proteases/farmacologia , Acetilcolinesterase/metabolismo , Doença de Alzheimer/tratamento farmacológico , Secretases da Proteína Precursora do Amiloide/metabolismo , Peptídeos beta-Amiloides/metabolismo , Animais , Ácido Aspártico Endopeptidases/metabolismo , Linhagem Celular Tumoral , Chalconas/síntese química , Chalconas/metabolismo , Chalconas/farmacocinética , Chlorocebus aethiops , Inibidores da Colinesterase/síntese química , Inibidores da Colinesterase/metabolismo , Inibidores da Colinesterase/farmacocinética , Electrophorus , Humanos , Camundongos , Simulação de Acoplamento Molecular , Fragmentos de Peptídeos/metabolismo , Inibidores de Proteases/síntese química , Inibidores de Proteases/farmacocinética , Ligação Proteica , Multimerização Proteica/efeitos dos fármacos , Células VeroRESUMO
BACKGROUND: Currently approved Alzheimer's disease medications mainly comprise acetylcholinesterase inhibitors. Many of these inhibitors are either natural compounds or synthetic molecules inspired in natural compounds. Hybrid molecules that can interact with different target sites of the enzyme could lead to the discovery of effective multitarget drugs. OBJECTIVE: To design, synthesize, and evaluate a series of new aza-resveratrol analogs as in vitro acetyl- and butyrylcholinesterase inhibitors. METHODS: The synthesis is achieved by a simple and efficient microwave-assisted method, from commercially available starting materials. Compounds are designed as hybrids of an aza-stilbene nucleus (Schiff base) connected to a tertiary amine by a hydrocarbon chain of variable length, designed to interact both with the peripheric anionic site and the catalytic site of the enzyme. RESULTS: All the derivatives inhibit both enzymes in a concentration-dependent manner, acting as moderate to potent cholinesterase inhibitors. The most potent inhibitors are compounds 12b (IC50 = 0.43 µM) and 12a (IC50 = 0.31 µM) for acetyl- and butyrylcholinesterase, respectively. Compounds 12a and 12b also exhibit significant acetylcholinesterase inhibition in SH-SY5Y human neuroblastoma cells without cytotoxic properties. Enzyme kinetic studies and molecular modeling reveal that inhibitor 12b targets both the catalytic active site and the peripheral anionic site of acetylcholinesterase what makes it able to modulate the self-induced ß-amyloid aggregation. Furthermore, the molecular modeling analysis helps to assess the impact of the linker length in the inhibitory activity of this family of new cholinesterase inhibitors. CONCLUSION: These compounds have the potential to serve as a dual binding site inhibitor and might provide a useful template for the development of new anti-Alzheimer's disease agents.
Assuntos
Inibidores da Colinesterase/síntese química , Resveratrol/síntese química , Acetilcolinesterase/metabolismo , Doença de Alzheimer/tratamento farmacológico , Sítios de Ligação , Butirilcolinesterase/metabolismo , Humanos , Micro-Ondas , Modelos Moleculares , Simulação de Acoplamento Molecular , Relação Estrutura-AtividadeRESUMO
The present work proposed the preparation of triazolic analogues of tyrosol, a biophenol found in olive oil and whose wide range of bioactivities has been the target of many studies. We obtained fifteen novel tyrosol derivatives and the compounds of the series were later evaluated as acetylcholinesterase (AChE) inhibitors. The study of AChE inhibition is important for the development of new drugs and pesticides, and especially the research for managing Alzheimer's disease. The most active compound, namely 7-({1-[2-(4-hydroxyphenyl)ethyl]-1H-1,2,3-triazol-4-yl}methoxy)-4-methyl-2H-chromen-2-one (30), showed IC50 value of 14.66⯱â¯2.29⯵mol L-1. Docking experiments corroborated by kinetic assay are suggestive of a competitive inhibition mechanism. Derivatives interacted with amino acids from the AChE active site associated to the development of Alzheimer's disease. The results indicate that the compounds synthesized have a high potential as prototypes for the development of new acetylcholinesterase inhibitors.
Assuntos
Acetilcolinesterase/metabolismo , Inibidores da Colinesterase/farmacologia , Triazóis/farmacologia , Animais , Inibidores da Colinesterase/síntese química , Inibidores da Colinesterase/química , Electrophorus , Simulação de Acoplamento Molecular , Estrutura Molecular , Triazóis/síntese química , Triazóis/químicaRESUMO
Herein, we report an eco-friendly, electrosynthetic approach for the intramolecular oxyselenylation of allyl-naphthol/phenol derivatives. This reaction proceeds with 0.2 equiv. of nBu4NClO4 as an electrolyte and Pt working electrodes in an undivided cell, resulting in the selenyl-dihydrofurans in good to excellent yields. Furthermore, several of the synthesized products presented a high percentage of acetylcholinesterase (AChE) inhibition, highlighting their potential anti-Alzheimer activity.
Assuntos
Inibidores da Colinesterase/farmacologia , Técnicas Eletroquímicas , Furanos/farmacologia , Naftóis/farmacologia , Compostos Organosselênicos/farmacologia , Fenóis/farmacologia , Acetilcolinesterase/metabolismo , Inibidores da Colinesterase/síntese química , Inibidores da Colinesterase/química , Relação Dose-Resposta a Droga , Eletrodos , Furanos/síntese química , Furanos/química , Humanos , Estrutura Molecular , Naftóis/química , Compostos Organosselênicos/síntese química , Compostos Organosselênicos/química , Fenóis/químicaRESUMO
During the last decade, the one drug-one target strategy has resulted to be inefficient in facing diseases with complex ethiology like Alzheimer's disease and many others. In this context, the multitarget paradigm has emerged as a promising strategy. Based on this consideration, we aim to develop novel molecules as promiscuous ligands acting in two or more targets at the same time. For such purpose, a new series of indolylpropyl-piperazinyl oxoethyl-benzamido piperazines were synthesized and evaluated as multitarget-directed drugs for the serotonin transporter (SERT) and acetylcholinesterase (AChE). The ability to decrease ß-amyloid levels as well as cell toxicity of all compounds were also measured. In vitro results showed that at least four compounds displayed promising activity against SERT and AChE. Compounds 18 and 19 (IC50 = 3.4 and 3.6 µM respectively) exhibited AChE inhibition profile in the same order of magnitude as donepezil (DPZ, IC50 = 2.17 µM), also displaying nanomolar affinity in SERT. Moreover, compounds 17 and 24 displayed high SERT affinities (IC50 = 9.2 and 1.9 nM respectively) similar to the antidepressant citalopram, and significant micromolar AChE activity at the same time. All the bioactive compounds showed a low toxicity profile in the range of concentrations studied. Molecular docking allowed us to rationalize the binding mode of the synthesized compounds in both targets. In addition, we also show that compounds 11 and 25 exhibit significant ß-amyloid lowering activity in a cell-based assay, 11 (50% inhibition, 10 µM) and 25 (35% inhibition, 10 µM). These results suggest that indolylpropyl benzamidopiperazines based compounds constitute promising leads for a multitargeted approach for Alzheimer's disease.