RESUMO
An increasing number of drugs introduced to the market and numerous repositories of compounds with confirmed activity have posed the need to revalidate the state-of-the-art rules that determine the ranges of properties the compounds should possess to become future drugs. In this study, we designed a series of two chemotypes of aryl-piperazine hydantoin ligands of 5-HT7R, an attractive target in search for innovative CNS drugs, with higher molecular weight (close to or over 500). Consequently, 14 new compounds were synthesised and screened for their receptor activity accompanied by extensive docking studies to evaluate the observed structure-activity/properties relationships. The ADMET characterisation in terms of the biological membrane permeability, metabolic stability, hepatotoxicity, cardiotoxicity, and protein plasma binding of the obtained compounds was carried out in vitro. The outcome of these studies constituted the basis for the comprehensive challenge of computational tools for ADMET properties prediction. All the compounds possessed high affinity to the 5-HT7R (Ki below 250 nM for all analysed structures) with good selectivity over 5-HT6R and varying affinity towards 5-HT2AR, 5-HT1AR and D2R. For the best compounds of this study, the expression profile of genes associated with neurodegeneration, anti-oxidant response and anti-inflammatory function was determined, and the survival of the cells (SH-SY5Y as an in vitro model of Alzheimer's disease) was evaluated. One 5-HT7R agent (32) was characterised by a very promising ADMET profile, i.e. good membrane permeability, low hepatotoxicity and cardiotoxicity, and high metabolic stability with the simultaneous high rate of plasma protein binding and high selectivity over other GPCRs considered, together with satisfying gene expression profile modulations and neural cell survival. Such encouraging properties make it a good candidate for further testing and optimisation as a potential agent in the treatment of CNS-related disorders.
RESUMO
The dopamine D4 receptor (D4R) is a promising therapeutic target in widespread diseases, and the search for novel agonists and antagonists appears to be clinically relevant. The mechanism of binding to the receptor (R) for antagonists and agonists varies. In the present study, we conducted an in-depth computational study, teasing out key similarities and differences in binding modes, complex dynamics, and binding energies for D4R agonists and antagonists. The dynamic network method was applied to investigate the communication paths between the ligand (L) and G-protein binding site (GBS) of human D4R. Finally, the fragment molecular orbitals with pair interaction energy decomposition analysis (FMO/PIEDA) scheme was used to estimate the binding energies of L-R complexes. We found that a strong salt bridge with D3.32 initiates the inhibition of the dopamine D4 receptor. This interaction also occurs in the binding of agonists, but the change in the receptor conformation to the active state starts with interaction with cysteine C3.36. Such a mechanism may arise in the case of agonists unable to form a hydrogen bond with the serine S5.46, considered, so far, to be crucial in the activation of GPCRs. The energy calculations using the FMO/PIEDA method indicate that antagonists show higher residue occupancy of the receptor binding site than agonists, suggesting they could form relatively more stable complexes. Additionally, antagonists were characterized by repulsive interactions with S5.46 distinguishing them from agonists.
Assuntos
Comunicação , Receptores de Dopamina D4 , Humanos , Sítios de Ligação , Cisteína , Interpretação Estatística de DadosRESUMO
Alzheimer's disease (AD) has a complex and not-fully-understood etiology. Recently, the serotonin receptor 5-HT6 emerged as a promising target for AD treatment; thus, here a new series of 5-HT6R ligands with a 1,3,5-triazine core and selenoether linkers was explored. Among them, the 2-naphthyl derivatives exhibited strong 5-HT6R affinity and selectivity over 5-HT1AR (13-15), 5-HT7R (14 and 15), and 5-HT2AR (13). Compound 15 displayed high selectivity for 5-HT6R over other central nervous system receptors and exhibited low risk of cardio-, hepato-, and nephrotoxicity and no mutagenicity, indicating its "drug-like" potential. Compound 15 also demonstrated neuroprotection against rotenone-induced neurotoxicity as well as antioxidant and glutathione peroxidase (GPx)-like activity and regulated antioxidant and pro-inflammatory genes and NRF2 nuclear translocation. In rats, 15 showed satisfying pharmacokinetics, penetrated the blood-brain barrier, reversed MK-801-induced memory impairment, and exhibited anxiolytic-like properties. 15's neuroprotective and procognitive-like effects, stronger than those of the approved drug donepezil, may pave the way for the use of selenotriazines to inhibit both causes and symptoms in AD therapy.
Assuntos
Doença de Alzheimer , Fármacos Neuroprotetores , Selênio , Ratos , Animais , Doença de Alzheimer/tratamento farmacológico , Serotonina/uso terapêutico , Ratos Wistar , Neuroproteção , Antioxidantes/farmacologia , Antioxidantes/uso terapêutico , Receptores de Serotonina , Fármacos Neuroprotetores/farmacologia , Fármacos Neuroprotetores/uso terapêuticoRESUMO
In order to find new hypotensive drugs possessing higher activity and better selectivity, a new series of fifteen 5,5-dimethylhydantoin derivatives (1-15) was designed. Three-step syntheses, consisting of N-alkylations using standard procedures as well as microwaves, were carried out. Crystal structures were determined for compounds 7-9. All of the synthesized 5,5-dimethylhydantoins were tested for their affinity to α1-adrenergic receptors (α1-AR) using both in vitro and in silico methods. Most of them displayed higher affinity (Ki < 127.9 nM) to α1-adrenoceptor than urapidil in radioligand binding assay. Docking to two subtypes of adrenergic receptors, α1A and α1B, was conducted. Selected compounds were tested for their activity towards two α1-AR subtypes. All of them showed intrinsic antagonistic activity. Moreover, for two compounds (1 and 5), which possess o-methoxyphenylpiperazine fragments, strong activity (IC50 < 100 nM) was observed. Some representatives (3 and 5), which contain alkyl linker, proved selectivity towards α1A-AR, while two compounds with 2-hydroxypropyl linker (11 and 13) to α1B-AR. Finally, hypotensive activity was examined in rats. The most active compound (5) proved not only a lower effective dose than urapidil but also a stronger effect than prazosin.
Assuntos
Hipotensão , Prazosina , Ratos , Animais , Prazosina/farmacologia , Anti-Hipertensivos/farmacologia , Ensaio Radioligante , Receptores Adrenérgicos alfa 1/metabolismo , Hipotensão/tratamento farmacológico , Antagonistas de Receptores Adrenérgicos alfa 1/farmacologiaRESUMO
Alzheimer's disease (AD), a neurodegenerative disorder with a complex aetiology, is the most common memory dysfunction particularly affecting the elderly. Various protein targets have been classified to be involved in the AD treatment, including 5-HT6 receptor (5-HT6R). So far, the 5-HT6R ligands obtained by our research group have become a good basis for hydrophobicity modulation to give a chance for more effective action toward AD by additional influence on target enzymes, e.g. cyclin-dependent kinase 5 (CDK5). In the search for 5-HT6R agents with additional inhibitory action on the enzyme, a series of 25 new 1,3,5-triazines (7-31) as modifications of lead, 4-[1-(2,5-dichlorophenoxy)propyl]-6-(4-methylpiperazin-1-yl)-1,3,5-triazine-2-amine (6), was rationally designed. Molecular modelling, synthesis, crystallographic studies, in vitro biological assays and behavioral studies in vivo were performed. The new triazines showed high affinity (Ki < 100 nM) and selectivity for 5-HT6R. The most effective one, 4-[1-(2,5-difluorophenoxy)propyl]-6-(4-methylpiperazin-1-yl)-1,3,5-triazine-2-amine (8), exhibited the strong antagonistic action towards 5-HT6R (Ki = 5 nM, pKb = 8.16), had an impact on the memory processes in the Novel Object Recognition test and displayed anxiolytic-like activity in the Elevated Plus Maze test in rats. Moreover, it had the antiplatelet effect as well as very good permeability (PAMPA model), high metabolic stability (RLMs) and satisfactory safety in vitro. Although the CDK5 inhibitory effects in vitro for the tested compounds (8, 10, 14, 18, 26-31) missed the potency expected from in silico simulations, the novel antagonist (8) with a very satisfying pharmacological and ADMET profile can serve as a new lead structure in further searches for innovative therapy against AD with accompanying symptoms.
Assuntos
Doença de Alzheimer , Ansiolíticos , Animais , Ratos , Doença de Alzheimer/tratamento farmacológico , Serotonina , Aminas , MemóriaRESUMO
Alzheimer's disease is becoming a growing problem increasing at a tremendous rate. Serotonin 5-HT6 receptors appear to be a particularly attractive target from a therapeutic perspective, due to their involvement not only in cognitive processes, but also in depression and psychosis. In this work, we present the synthesis and broad biological characterization of a new series of 18 compounds with a unique 1,3,5-triazine backbone, as potent 5-HT6 receptor ligands. The main aim of this research is to compare the biological activity of the newly synthesized sulfur derivatives with their oxygen analogues and their N-demethylated O- and S-metabolites obtained for the first time. Most of the new triazines displayed high affinity (Ki < 200 nM) and selectivity towards 5-HT6R, with respect to 5-HT2AR, 5-HT7R, and D2R, in the radioligand binding assays. For selected, active compounds crystallographic studies, functional bioassays, and ADME-Tox profile in vitro were performed. The exciting novelty is that the sulfur derivatives exhibit an agonistic mode of action contrary to all other compounds obtained to date in this chemical class herein and previously reported. Advanced computational studies indicated that this intriguing functional shift might be caused by presence of chalcogen bonds formed only by the sulfur atom. In addition, the N-demethylated derivatives have emerged highly potent antioxidants and, moreover, show a significant improvement in metabolic stability compared to the parent structures. The cholinesterase study present micromolar inhibitory AChE and BChE activity for both 5-HT6 agonist 19 and potent antagonist 5. Finally, the behavioral experiments of compound 19 demonstrated its antidepressant-like properties and slight ability to improve cognitive deficits, without inducing memory impairments by itself. Described pharmacological properties of both compounds (5 and 19) allow to give a design clue for the development of multitarget compounds with 5-HT6 (both agonist and antagonist)/AChE and/or BChE mechanism in the group of 1,3,5-triazine derivatives.
Assuntos
Doença de Alzheimer , Calcogênios , Humanos , Doença de Alzheimer/tratamento farmacológico , Serotonina , Estrutura Molecular , Relação Estrutura-Atividade , Receptores de Serotonina/metabolismo , Ligantes , Triazinas/química , Éteres , Inibidores da Colinesterase/farmacologia , Inibidores da Colinesterase/uso terapêutico , Acetilcolinesterase/metabolismoRESUMO
Lymphomas are still difficult to treat even with modern therapies as, among others, multidrug resistance (MDR) is often counteracting a successful cancer therapy. P-gp/ABC-transporters are well-known for their crucial role in the main tumour MDR mechanism, eliminating drugs and cytotoxic substances from the cancer cell by efflux, and their modulators are promising for innovative therapy, but none has been approved in the pharmaceutical market yet. Herein, we have designed, synthesised and analysed 30 novel seleno- and thioether 1,3,5-triazine derivatives conducting comprehensive studies to evaluate their potential application in human JURKAT lymphoma cells. Among the new compounds, four (11, 12, 13 and 23) were much more effective than the reference inhibitor verapamil, being potent ABCB1 inhibitors already at 2 µM, while 5 and 15 showed very potent ABCB1 inhibitory activity only at 20 µM. Results of P-gp ATPase assays, supported with docking studies, indicated the competitive substrate mode of modulating action for 15, while ABCB1, ABCC1 and ABCG2 genes expression induction by 15 with q-PCR was confirmed. All compounds were evaluated for their cytotoxic and antiproliferative properties in both sensitive (PAR) and resistant (MDR) mouse T-lymphoma cell lines, and compound 15, also considering its promising ABCB1 inhibition properties, was revealed to be the best compound in terms of its cytotoxic effect (IC50: 16.73 µM) as well as concerning the antiproliferative effect (IC50: 5.35 µM) in MDR cells. Regarding the mechanistic studies looking at the cell cycle, the thioether 15 and selenium derivatives 26 and 29 were significantly effective in the regulation of cell cycle-related genes alone or in co-treatment with doxorubicin counteracting Cyclin D1 and E1 expression and increasing p53 and p21 levels, shedding first light on their mechanism of action. In summary, we explored the chemical space of seleno- and thioether 1,3,5-triazine derivatives with interesting activity against lymphoma. Especially compound 15 is worthy of being studied deeper to evaluate its precise mode of action further as well it can be improved regarding its potency and drug-likeness.
Assuntos
Antineoplásicos , Linfoma , Camundongos , Animais , Humanos , Membro 2 da Subfamília G de Transportadores de Cassetes de Ligação de ATP/metabolismo , Sulfetos/farmacologia , Resistencia a Medicamentos Antineoplásicos , Proteínas de Neoplasias , Resistência a Múltiplos Medicamentos , Antineoplásicos/farmacologia , Antineoplásicos/química , Linfoma/tratamento farmacológico , Preparações Farmacêuticas , Triazinas/farmacologia , Linhagem Celular TumoralRESUMO
In view of the unsatisfactory treatment of cognitive disorders, in particular Alzheimer's disease (AD), the aim of this review was to perform a computer-aided analysis of the state of the art that will help in the search for innovative polypharmacology-based therapeutic approaches to fight against AD. Apart from 20-year unrenewed cholinesterase- or NMDA-based AD therapy, the hope of effectively treating Alzheimer's disease has been placed on serotonin 5-HT6 receptor (5-HT6R), due to its proven, both for agonists and antagonists, beneficial procognitive effects in animal models; however, research into this treatment has so far not been successfully translated to human patients. Recent lines of evidence strongly emphasize the role of kinases, in particular microtubule affinity-regulating kinase 4 (MARK4), Rho-associated coiled-coil-containing protein kinase I/II (ROCKI/II) and cyclin-dependent kinase 5 (CDK5) in the etiology of AD, pointing to the therapeutic potential of their inhibitors not only against the symptoms, but also the causes of this disease. Thus, finding a drug that acts simultaneously on both 5-HT6R and one of those kinases will provide a potential breakthrough in AD treatment. The pharmacophore- and docking-based comprehensive literature analysis performed herein serves to answer the question of whether the design of these kind of dual agents is possible, and the conclusions turned out to be highly promising.
Assuntos
Doença de Alzheimer , Transtornos Cognitivos , Doença de Alzheimer/metabolismo , Animais , Transtornos Cognitivos/etiologia , Humanos , Ligantes , Receptores de Serotonina/metabolismo , Serotonina , Antagonistas da Serotonina/farmacologiaRESUMO
This research allowed us to find the first highly potent 5-HT6/5-HT2A receptor (5-HT6/5-HT2AR) dual antagonists in a group of 1,3,5-triazine compounds as a result of an exit beyond the hydrophobic feature of the pharmacophore model for 5-HT6R antagonists. Design and synthesis of the series (2-16) of new O- and S-containing ether derivatives of 1,3,5-triazines with the double-ring aromatic region have been performed. The new compounds were examined within the comprehensive pharmacological screening, including: radioligand binding assays, functional and ADMET studies in vitro as well as behavioral tests in rats. Crystallographic aspects and computer-aided structure-activity relationship were analyzed, as well. The comprehensive approach led to selection of compound 12 (4-(4-methylpiperazin-1-yl)-6-(2-(naphthalen-2-ylthio)propan-2-yl)-1,3,5-triazin-2-amine) with the most significant dual 5-HT6/5-HT2AR antagonistic action (5-HT6R Ki = 11 nM, 5-HT2AR Ki = 39 nM). Moreover, the compound 12 has satisfactory ADMETox properties in vitro, i.e.: the high permeability through biological membranes, high metabolic stability, neither mutagenic nor hepatotoxic effects, and moderate ability to inhibit CYP3A4. Above all, 12 showed ability to reverse the pharmacologically-induced (MK-801) memory impairment at low doses (1-3 mg/kg) in Novel Object Recognition (NOR) test in rats. Our results indicate a promising potency of dual 5-HT6/5-HT2AR antagonism in the search for novel strategy to fight Alzheimer's disease, which remains an unmet clinical need.
Assuntos
Receptores de Serotonina , Antagonistas da Serotonina , Animais , Estrutura Molecular , Ratos , Receptores de Serotonina/metabolismo , Serotonina , Triazinas/química , Triazinas/farmacologiaRESUMO
Several studies confirmed the reciprocal interactions between adrenergic and serotoninergic systems and the influence of these phenomena on the pathogenesis of anxiety. Hence, searching for chemical agents with a multifunctional pharmacodynamic profile may bring highly effective therapy for CNS disorders. This study presents a deep structural insight into the hydantoin-arylpiperazine group and their serotonin/α-adrenergic activity. The newly synthesized compounds were tested in the radioligand binding assay and the intrinsic activity was evaluated for the selected derivatives. The computer-aided SAR analysis enabled us to answer questions about the influence of particular structural fragments on selective vs. multifunctional activity. As a result of the performed investigations, there were two leading structures: (a) compound 12 with multifunctional adrenergic-serotonin activity, which is a promising candidate to be an effective anxiolytic agent; (b) compound 14 with high α1A/α1D affinity and selectivity towards α1B, which is recommended due to the elimination of probable cardiotoxic effect. The structural conclusions of this work provide significant support for future lead optimization in order to achieve the desired pharmacodynamic profile in searching for new CNS-modulating agents.
Assuntos
Antagonistas de Receptores Adrenérgicos alfa 1 , Ansiolíticos , Estrutura Molecular , Receptores Adrenérgicos alfa 1 , Antagonistas de Receptores Adrenérgicos alfa 1/química , Antagonistas de Receptores Adrenérgicos alfa 1/farmacologia , Animais , Ansiolíticos/química , Ansiolíticos/farmacologia , Células HEK293 , Humanos , Piperazinas/química , Piperazinas/farmacologia , Ratos , Receptores Adrenérgicos alfa 1/química , Receptores Adrenérgicos alfa 1/metabolismoRESUMO
Among the serotonin receptors, one of the most recently discovered 5-HT6 subtype is an important protein target and its ligands may play a key role in the innovative treatment of cognitive disorders. However, none of its selective ligands have reached the pharmaceutical market yet. Recently, a new chemical class of potent 5-HT6 receptor agents, the 1,3,5-triazine-piperazine derivatives, has been synthesized. Three members, the ortho and meta dichloro- (1,2) and the unsubstituted phenyl (3) derivatives, proved to be of special interest due to their high affinities (1,2) and selectivity (3) toward 5-HT6 receptor. Thus, a broader pharmacological profile for 1-3, including comprehensive screening of the receptor selectivity and drug-like parameters in vitro as well as both, pharmacokinetic and pharmacodynamic properties in vivo, have been investigated within this study. A comprehensive analysis of the obtained results indicated significant procognitive-like activity together with beneficial drug-likeness in vitro and pharmacokinetics in vivo profiles for both, (RS)-4-[1-(2,3-dichlorophenoxy)propyl]-6-(4-methylpiperazin-1-yl)-1,3,5-triazin-2-amine (2) and (RS)-4-(4-methylpiperazin-1-yl)-6-(1-phenoxypropyl)-1,3,5-triazin-2-amine (3), but insensibly predominant for compound 2. Nevertheless, both compounds (2 and 3) seem to be good Central Nervous System drug candidates in search for novel therapeutic approach to dementia diseases, based on the 5-HT6 receptor target.
Assuntos
Transtornos Cognitivos/tratamento farmacológico , Demência/tratamento farmacológico , Receptores de Serotonina/química , Antagonistas da Serotonina/farmacologia , Triazinas/farmacologia , Animais , Células CACO-2 , Humanos , Masculino , Estrutura Molecular , Ratos , Ratos Wistar , Receptores de Serotonina/metabolismo , Antagonistas da Serotonina/química , Relação Estrutura-Atividade , Triazinas/químicaRESUMO
Despite the better understanding of the mechanisms underlying Alzheimer's Disease (AD) and launched clinical trials, no AD-modifying treatment based on a synthetic drug has been introduced for almost twenty years. The serotonin 5-HT6 and 5-HT7 receptors turned out to be promising biological targets for modulation of central nervous system dysfunctions including cognitive impairment. Within this paper, we evaluate the pharmacological potency of both, 5-HT6R and 5-HT7R, agents in search for novel AD treatment. An overview of chemical structures of the 5-HTRs ligands with simultaneous procognitive action which have undergone preclinical and clinical studies within the last 10 years has been performed.
Assuntos
Doença de Alzheimer/tratamento farmacológico , Nootrópicos/uso terapêutico , Receptores de Serotonina/metabolismo , Antagonistas da Serotonina/uso terapêutico , Agonistas do Receptor de Serotonina/uso terapêutico , Animais , Humanos , Nootrópicos/química , Antagonistas da Serotonina/química , Agonistas do Receptor de Serotonina/químicaRESUMO
ABCB1 modulation is an interesting strategy in the search for new anticancer agents that can overcome multidrug resistance (MDR). Hence, 17 new 5-arylideneimidazolones containing an amine moiety, as potential ABCB1 inhibitors, were designed, synthesized, and investigated. The series was tested in both parental (PAR) and multidrug-resistant (MDR) ABCB1-overexpressing T-lymphoma cancer cells using cytotoxicity assays. The ABCB1-modulating activity was examined in rhodamine 123 accumulation tests, followed by Pgp-Glo™ Assay to determine the influence of the most active compounds on ATPase activity. Lipophilic properties were assessed both, in silico and experimentally (RP-TLC). Pharmacophore-based molecular modelling toward ABCB1 modulation was performed. The studies allowed the identification of anticancer agents (p-fluorobenzylidene derivatives) more potent than doxorubicin, with highly selective action on MDR T-lymphoma cells (selectivity index >40). Most of the investigated compounds showed ABCB1-modulating action; in particular, two 5-benzyloxybenzylidene derivatives displayed activity nearly as strong as that of tariquidar.
Assuntos
Antineoplásicos/farmacologia , Desenho Assistido por Computador , Resistência a Múltiplos Medicamentos/efeitos dos fármacos , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Imidazóis/farmacologia , Subfamília B de Transportador de Cassetes de Ligação de ATP/antagonistas & inibidores , Subfamília B de Transportador de Cassetes de Ligação de ATP/metabolismo , Animais , Antineoplásicos/síntese química , Antineoplásicos/química , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Imidazóis/síntese química , Imidazóis/química , Camundongos , Relação Estrutura-Atividade , Células Tumorais CultivadasRESUMO
A series of 17 arylpiperazine derivatives of the 5-spiroimidazolidine-2,4-diones (6-22) has been explored, including variations in (i) the number of aromatic rings at position 5, (ii) the length of the linker, as well as (iii) the kind and position of the linked arylpiperazine terminal fragment. Synthesis (6-16) and X-ray crystallographic studies for representative compounds (8, 10, 14 and 18) have been performed. The ability to inhibit the tumor multidrug resistance (MDR) efflux pump P-glycoprotein (P-gp, ABCB1) overexpressed in mouse T-lymphoma cells was investigated. The cytotoxic and antiproliferative actions of the compounds on both the reference and the ABCB1-overproducing cells were also examined. The pharmacophore-based molecular modeling studies have been performed. ADMET properties in vitro of selected most active derivatives (6, 11 and 12) have been determined. All compounds, excluding 18, inhibited the cancer P-gp efflux pump with higher potency than that of reference verapamil. The spirofluorene derivatives with amine alkyl substituents at position 1, and the methyl group at position 3 (6-16), occurred the most potent P-gp inhibitors in the MDR T-lymphoma cell line. In particular, compounds 7 and 12 were 100-fold more potent than verapamil. Crystallography-supported pharmacophore-based SAR analysis has postulated specific structural properties that could explain this excellent cancer MDR-inhibitory action.
Assuntos
Antineoplásicos/farmacologia , Imidazolidinas/farmacologia , Linfoma de Células T/tratamento farmacológico , Compostos de Espiro/farmacologia , Antineoplásicos/síntese química , Antineoplásicos/química , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Relação Dose-Resposta a Droga , Resistência a Múltiplos Medicamentos/efeitos dos fármacos , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Imidazolidinas/síntese química , Imidazolidinas/química , Linfoma de Células T/metabolismo , Linfoma de Células T/patologia , Simulação de Acoplamento Molecular , Estrutura Molecular , Compostos de Espiro/síntese química , Compostos de Espiro/química , Relação Estrutura-AtividadeRESUMO
The mitogen-activated protein kinase (MAPK)-interacting kinases 1 and 2 (MNKs 1/2) and their downstream target eIF4E, play a role in oncogenic transformation, progression and metastasis. These results provided rationale for development of first MNKs inhibitors, currently in clinical trials for cancer treatment. Inhibitors of the MNKs/eIF4E pathway are also proposed as treatment strategy for inflammatory conditions. Here we present results of optimization of indazole-pyridinone derived MNK1/2 inhibitors among which compounds 24 and 26, selective and metabolically stable derivatives. Both compounds decreased levels of eIF4E Ser206 phosphorylation (pSer209-eIF4E) in MOLM16 cell line. When administered in mice compounds 24 and 26 significantly improved survival rates of animals in the endotoxin lethal dose challenge model, with concomitant reduction of proinflammatory cytokine levels - TNFα and IL-6 in serum. Identified MNK1/2 inhibitors represent a novel class of immunomodulatory compounds with a potential for the treatment of inflammatory diseases including sepsis.
Assuntos
Fatores Imunológicos/síntese química , Indazóis/química , Peptídeos e Proteínas de Sinalização Intracelular/antagonistas & inibidores , Inibidores de Proteínas Quinases/síntese química , Proteínas Serina-Treonina Quinases/antagonistas & inibidores , Piridonas/química , Choque Séptico/tratamento farmacológico , Sequência de Aminoácidos , Animais , Citocinas/metabolismo , Relação Dose-Resposta a Droga , Descoberta de Drogas , Endotoxinas/metabolismo , Fator de Iniciação 4E em Eucariotos/metabolismo , Humanos , Fatores Imunológicos/farmacologia , Camundongos , Simulação de Acoplamento Molecular , Ligação Proteica , Inibidores de Proteínas Quinases/farmacologia , Choque Séptico/induzido quimicamente , Transdução de Sinais , Relação Estrutura-AtividadeRESUMO
This study concerns synthesis and evaluation of pharmacodynamic and pharmacokinetic profile for all four stereoisomers of MF-8 (5-(4-fluorophenyl)-3-(2-hydroxy-3-(4-(2-methoxyphenyl)piperazin-1-yl)propyl)-5-methylimidazolidine-2,4-dione), the previously described, highly potent 5-HT7R ligand with antidepressant activity on mice. The combination of DFT calculations of 1H NMR chemical shifts with docking and dynamic simulations, in comparison to experimental screening results, provided prediction of the configuration for one of two present stereogenic centers. The experimental data for stereoisomers (MF-8A-MF-8D) confirmed the significant impact of stereochemistry on both, 5-HT7R affinity and antagonistic action, with Ki and Kb values in the range of 3-366 nM and 0.024-99 µM, respectively. We also indicated the stereochemistry-dependent influence of the tested compounds on P-glycoprotein efflux, absorption in Caco-2 model, metabolic pathway as well as CYP3A4 and CYP2C9 activities.
Assuntos
Hidantoínas/farmacocinética , Piperazinas/farmacocinética , Antagonistas da Serotonina/farmacocinética , Animais , Sítios de Ligação , Linhagem Celular Tumoral , Citocromo P-450 CYP2C9/química , Citocromo P-450 CYP2C9/metabolismo , Inibidores do Citocromo P-450 CYP3A/síntese química , Inibidores do Citocromo P-450 CYP3A/metabolismo , Inibidores do Citocromo P-450 CYP3A/farmacocinética , Inibidores do Citocromo P-450 CYP3A/toxicidade , Teoria da Densidade Funcional , Estabilidade de Medicamentos , Humanos , Hidantoínas/síntese química , Hidantoínas/metabolismo , Hidantoínas/toxicidade , Camundongos , Microssomos Hepáticos/metabolismo , Modelos Químicos , Simulação de Acoplamento Molecular , Simulação de Dinâmica Molecular , Piperazinas/síntese química , Piperazinas/metabolismo , Piperazinas/toxicidade , Ligação Proteica , Espectroscopia de Prótons por Ressonância Magnética , Receptores de Serotonina/química , Receptores de Serotonina/metabolismo , Antagonistas da Serotonina/síntese química , Antagonistas da Serotonina/metabolismo , Antagonistas da Serotonina/toxicidade , EstereoisomerismoRESUMO
In the light of recent lines of evidence, 5-HT6R ligands are a promising tool for future treatment of memory impairment. Hence, this study has supplied highly potent 5-HT6R agents with procognitive effects, which represent an original chemical class of 1,3,5-triazines, different from widely studied sulfone and indole-like 5-HT6R ligands. The new compounds were rationally designed as modifications of lead, 4-(1-(2-chlorophenoxy)ethyl)-6-(4-methylpiperazin-1-yl)-1,3,5-triazin-2-amine (1), involving an introduction of: (i) two chlorines at benzene ring and (ii) varied linkers joining the triazine ring to aromatic ethers. Synthesis, in vitro and in vivo biological tests and computer-aided SAR analysis for 19 new compounds were carried out. Most of the new triazines displayed high affinity (Ki < 100 nM) and selectivity towards 5-HT6R, with respect to 5-HT2AR, 5-HT7R and D2R. The crystallography-supported docking studies, including quantum-polarized ligand docking (QPLD), indicated that chlorine atoms may be involved in different type of halogen bonding, however, the linker properties seem to predominately affect the 5-HT6R affinity. 4-[1-(2,5-Dichlorophenoxy)propyl]-6-(4-methylpiperazin-1-yl)-1,3,5-triazin-2-amine (9), which displayed: the highest affinity (Ki = 6 nM), very strong 5-HT6R antagonistic action (KB = 27 pM), procognitive effects in vivo in novel object recognition (NOR) test in rats, a very good permeability in PAMPA model and satisfying safety in vitro, was identified as the most potent 1,3,5-triazine agent so far, useful as a new lead for further research.
Assuntos
Cloro/química , Cognição/efeitos dos fármacos , Receptores de Serotonina/metabolismo , Triazinas/química , Triazinas/farmacologia , Animais , Simulação de Acoplamento Molecular , Conformação Proteica , Ratos , Receptores de Serotonina/química , Segurança , Relação Estrutura-Atividade , Triazinas/metabolismoRESUMO
Recently, a computational approach combining a structure-activity relationship library containing pairs of halogenated ligands and their corresponding unsubstituted ligands (called XSAR) with QM-based molecular docking and binding free energy calculations was developed and used to search for amino acids frequently targeted by halogen bonding, also known as XB hot spots. However, the analysis of ligand-receptor complexes with halogen bonds obtained by molecular docking provides a limited ability to study the role and significance of halogen bonding in biological systems. Thus, a set of molecular dynamics simulations for the dopamine D4 receptor, recently crystallized with the antipsychotic drug nemonapride (5WIU), and the five XSAR sets were performed to verify the identified hot spots for halogen bonding, in other words, primary (V5x40), and secondary (S5x43, S5x461 and H6x55). The simulations confirmed the key role of halogen bonding with V5x40 and H6x55 and supported S5x43 and S5x461. The results showed that steric restrictions and the topology of the molecular core have a crucial impact on the stabilization of the ligand-receptor complex by halogen bonding.
Assuntos
Halogênios/metabolismo , Simulação de Dinâmica Molecular , Receptores de Dopamina D4/metabolismo , Ligantes , Relação Estrutura-AtividadeRESUMO
This research has provided the most active 5-HT6R agents among 1,3,5-triazine derivatives investigated to date and has also identified the world's first selenium-containing 5-HT6R ligands. The studies are focused on design, synthesis, biological evaluation and docking-supported SAR analysis for novel 5-HT6R agents as derivatives of lead structure 4-(4-methylpiperazin-1-yl)-6-(phenoxymethyl)-1,3,5-triazin-2-amine (7). The lead modifications included an introduction of: (i) various small substituents at benzene ring, (ii) a branched ether linker or (iii) the ether oxygen replacement with other chalcogen (S, Se) or sulfonyl moiety. Hence, a series of new compounds (7-24) was synthesized and examined on their affinities for 5-HT6R and selectivity, in respect to the 5-HT1AR, 5-HT2AR, 5-HT7R and dopamine D2 receptor, in the radioligand binding assays. For representative most active compounds functional bioassays and toxicity profile in vitro and antidepressant-like activity in vivo were examined. The 2-isopropyl-5-methylphenyl derivative (10) was found as the most active triazine 5-HT6R antagonist (Kiâ¯=â¯11â¯nM). SAR analysis indicated, that an exchange of oxygen to selenium (7 vs. 22), and especially, to sulfur (7 vs. 19) was beneficial to increase both affinity and antagonistic action for 5-HT6R. Surprisingly, an introduction of SO2 caused a drastic decrease of the 5-HT6R affinity, which was explained at a molecular level based on docking studies. All in vivo tested compounds (10, 18 and 21) did not show any risk of toxicity in the safety studies in vitro.
Assuntos
Processamento de Imagem Assistida por Computador , Receptores de Serotonina/metabolismo , Antagonistas da Serotonina/farmacologia , Animais , Linhagem Celular Tumoral , Relação Dose-Resposta a Droga , Humanos , Ligantes , Locomoção/efeitos dos fármacos , Modelos Moleculares , Estrutura Molecular , Ratos , Antagonistas da Serotonina/síntese química , Antagonistas da Serotonina/química , Relação Estrutura-AtividadeRESUMO
In order to search for active and selective serotonin 5-HT7R antagonists among 3,5-disubstituted arylpiperazine-imidazolidine-2,4-diones, the role of the introduction/deletion and the mutual orientation of aromatic rings was analyzed. Chemical modifications of 2nd generation lead structure of 3-(3-(4-(diphenylmethyl)piperazin-1-yl)-2-hydroxypropyl)-5-(4-fluorophenyl)-5-methylimidazolidine-2,4-dione (2, KKB16) were performed. New derivatives (4-18) were designed and synthesized. X-ray crystallographic analysis of the representative compound 5-(4-fluorophenyl)-3-[2-hydroxy-3-(4-phenylpiperazin-1-yl)propyl]-5-methylimidazolidine-2,4-dione (3) was performed to support molecular modeling and SAR studies. The affinity for 5-HT7R, D2R and 5-HT1AR in radioligand binding assays for the entire series and ADME-Tox parameters in vitro for selected compounds (7, 10, and 13) were evaluated. Molecular docking and pharmacophore model assessment were performed. According to the obtained results, 5-methyl-5-naphthylhydantoin derivatives were found to be the new highly active 5-HT7R agents (Ki ≤ 5 nM) with significant selectivity over 5-HT1AR and D2R. On the contrary, the (1-naphthyl)piperazine moiety was gained with the potent dual 5-HT7R/5-HT1AR action (Ki: 11 nM/19 nM).