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Research on the energy metabolism of cancer cells is becoming a central element in oncology, and in recent decades, it has allowed us to better understand the mechanisms underlying the onset and chemoresistance of oncological pathologies. Mitochondrial bioenergetic processes, in particular, have proven to be fundamental for the survival of tumor stem cells (CSC), a subpopulation of tumor cells responsible for tumor recurrence, the onset of metastasis, and the failure of conventional anticancer therapies. Over the years, numerous natural products, in particular flavonoids, widely distributed in the plant kingdom, have been shown to interfere with tumor bioenergetics, demonstrating promising antitumor effects. Herein, the anticancer potential of Licoflavanone, a flavanone isolated from the leaves of G. glabra, was explored for the first time in breast cancer cells. The results obtained highlighted a marked antitumor activity that proved to be greater than that mediated by Glabranin or Pinocembrin, flavanones isolated from the same plant matrix. Furthermore, the investigation of Licoflavanone's effects on breast cancer energy metabolism highlighted the inhibitory activity of this natural product on tumor bioenergetics, a mechanism that could underlie its ability to reduce tumor proliferation, invasiveness, and stemness.
Assuntos
Neoplasias da Mama , Metabolismo Energético , Flavanonas , Glycyrrhiza , Humanos , Flavanonas/farmacologia , Flavanonas/química , Neoplasias da Mama/metabolismo , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/patologia , Metabolismo Energético/efeitos dos fármacos , Feminino , Glycyrrhiza/química , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Células-Tronco Neoplásicas/efeitos dos fármacos , Células-Tronco Neoplásicas/metabolismo , Antineoplásicos Fitogênicos/farmacologia , Antineoplásicos Fitogênicos/química , Extratos Vegetais/farmacologia , Extratos Vegetais/química , Células MCF-7RESUMO
The endocannabinoid system (ECS) is a critical regulatory network composed of endogenous cannabinoids (eCBs), their synthesizing and degrading enzymes, and associated receptors. It is integral to maintaining homeostasis and orchestrating key functions within the central nervous and immune systems. Given its therapeutic significance, we have launched a series of drug discovery endeavors aimed at ECS targets, including peroxisome proliferator-activated receptors (PPARs), cannabinoid receptors types 1 (CB1R) and 2 (CB2R), and monoacylglycerol lipase (MAGL), addressing a wide array of medical needs. The pursuit of new therapeutic agents has been enhanced by the creation of specialized labeled chemical probes, which aid in target localization, mechanistic studies, assay development, and the establishment of biomarkers for target engagement. By fusing medicinal chemistry with chemical biology in a comprehensive, translational end-to-end drug discovery strategy, we have expedited the development of novel therapeutics. Additionally, this strategy promises to foster highly productive partnerships between industry and academia, as will be illustrated through various examples.
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Química Farmacêutica , Descoberta de Drogas , Endocanabinoides , Endocanabinoides/metabolismo , Endocanabinoides/química , Humanos , Indústria Farmacêutica , Monoacilglicerol Lipases/metabolismo , Monoacilglicerol Lipases/antagonistas & inibidores , Desenvolvimento de Medicamentos , AcademiaRESUMO
Parasitic diseases cause significant global morbidity and mortality particularly in the poorest regions of the world. Schistosomiasis, one of the most widespread neglected tropical diseases, affects more than 200 million people worldwide. Histone deacetylase (HDAC) inhibitors are prominent epigenetic drugs that are being investigated in the treatment of several diseases, including cancers and parasitic diseases. Schistosoma mansoni HDAC8 (SmHDAC8) is highly expressed in all life cycle stages of the parasite, and selective inhibition is required in order to avoid undesirable off-target effects in the host. Herein, by X-ray crystal structures of SmHDAC8-inhibitor complexes, biochemical and phenotypic studies, we found two schistosomicidal spiroindoline derivatives binding a novel site, next to Trp198, on the enzyme surface. We determined that by acting on this site, either by mutation of the Trp198 or by compound binding, a decrease in the activity of the enzyme is achieved. Remarkably, this allosteric site differs from the human counterpart; rather, it is conserved in all Schistosoma species, as well as Rhabidoptera and Trematoda classes, thus paving the way for the design of HDAC8-selective allosteric inhibitors with improved properties.
Assuntos
Anti-Helmínticos , Proteínas de Helminto , Inibidores de Histona Desacetilases , Histona Desacetilases , Schistosoma mansoni , Animais , Humanos , Sítios de Ligação , Proteínas de Helminto/química , Proteínas de Helminto/genética , Inibidores de Histona Desacetilases/farmacologia , Inibidores de Histona Desacetilases/química , Histona Desacetilases/química , Histona Desacetilases/genética , Schistosoma mansoni/enzimologia , Schistosoma mansoni/genética , Anti-Helmínticos/química , Anti-Helmínticos/farmacologia , Cristalografia por Raios XRESUMO
Morin is a vasorelaxant flavonoid, whose activity is ascribable to CaV1.2 channel blockade that, however, is weak as compared to that of clinically used therapeutic agents. A conventional strategy to circumvent this drawback is to synthesize new derivatives differently decorated and, in this context, morin-derivatives able to interact with CaV1.2 channels were found by employing the potential of PLATO in target fishing and reverse screening. Three different derivatives (5a-c) were selected as promising tools, synthesized, and investigated in in vitro functional studies using rat aorta rings and rat tail artery myocytes. 5a-c were found more effective vasorelaxant agents than the naturally occurring parent compound and antagonized both electro- and pharmaco-mechanical coupling in an endothelium-independent manner. 5a, the series' most potent, reduced also Ca2+ mobilization from intracellular store sites. Furthermore, 5a≈5c > 5b inhibited Ba2+ current through CaV1.2 channels. However, compound 5a caused also a concentration-dependent inhibition of KCa1.1 channel currents.
Assuntos
Inteligência Artificial , Bloqueadores dos Canais de Cálcio , Canais de Cálcio Tipo L , Flavonoides , Vasodilatação , Vasodilatadores , Animais , Ratos , Flavonoides/farmacologia , Vasodilatadores/química , Vasodilatadores/farmacologia , Bloqueadores dos Canais de Cálcio/química , Bloqueadores dos Canais de Cálcio/farmacologia , Canais de Cálcio Tipo L/metabolismoRESUMO
Topoisomerases are ubiquitous enzymes in the human body, particularly involved in cancer development and progression. Topoisomerase I (topoI) performs DNA relaxation reactions by "controlled rotation" rather than by "strand passage." The inhibition of topoI has become a useful strategy to control cancer cell proliferation. Nowadays, different compounds have undergone clinical trials, but the search for new molecular entities is necessary and benefits from medicinal chemistry efforts. Pyrrole-based compounds emerged as promising antiproliferative agents, with particular interest in breast cancer therapy and topoI inhibition. Starting from these observations and based on the scaffold-hopping approach, we developed a small library of 1-(2-aminophenyl)pyrrole-based amides (7a-f) as new anticancer agents. Tested on a panel of cancer cell lines, 7a-f displayed the most interesting profile in MDA-MB-231 cells, where the most active compounds, 7d-f, were able to induce death by apoptosis. Direct enzymatic assays and docking simulations on the topoI active site (PDB: 1A35) revealed the inhibitory activity and potential binding site for the newly developed 1-(2-aminophenyl)pyrrole-based amides.
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Aiming to simultaneously modulate the endocannabinoid system (ECS) functions and the epigenetic machinery, we selected the fatty acid amide hydrolase (FAAH) and histone deacetylase (HDAC) enzymes as desired targets to develop potential neuroprotective multitarget-directed ligands (MTDLs), expecting to achieve an additive or synergistic therapeutic effect in oxidative stress-related conditions. We herein report the design, synthesis, and biological evaluation of the first-in-class FAAH-HDAC multitarget inhibitors. A pharmacophore merging strategy was applied, yielding 1-phenylpyrrole-based compounds 4a-j. The best-performing compounds (4c, 4f, and 4h) were tested for their neuroprotective properties in oxidative stress models, employing 1321N1 human astrocytoma cells and SHSY5 human neuronal cells. In our preliminary studies, compound 4h stood out, showing a balanced nanomolar inhibitory activity against the selected targets and outperforming the standard antioxidant N-acetylcysteine in vitro. Together with 4f, 4h was also able to protect 1321N1 cells from tert-butyl hydroperoxide or glutamate insult. Our study may provide the basis for the development of novel MTDLs targeting the ECS and epigenetic enzymes.
Assuntos
Inibidores de Histona Desacetilases , Fármacos Neuroprotetores , Humanos , Inibidores de Histona Desacetilases/farmacologia , Fármacos Neuroprotetores/farmacologia , Relação Estrutura-Atividade , AmidoidrolasesRESUMO
Pseudomonas aeruginosa (PA), one of the ESKAPE pathogens, is an opportunistic Gram-negative bacterium responsible for nosocomial infections in humans but also for infections in patients affected by AIDS, cancer, or cystic fibrosis (CF). Treatment of PA infections in CF patients is a global healthcare problem due to the ability of PA to gain antibiotic tolerance through biofilm formation. Anti-virulence compounds represent a promising approach as adjuvant therapy, which could reduce or eliminate the pathogenicity of PA without impacting its growth. Pyocyanin is one of the virulence factors whose production is modulated by the Pseudomonas quinolone signal (PQS) through its receptor PqsR. Different PqsR modulators have been synthesized over the years, highlighting this new powerful therapeutic strategy. Based on the promising structure of quinazolin-4(3H)-one, we developed compounds 7a-d, 8a,b, 9, 10, and 11a-f able to reduce biofilm formation and the production of virulence factors (pyocyanin and pyoverdine) at 50 µM in two PA strains responsible for CF acute and chronic infections. The developed compounds did not reduce the cell viability of IB3-1 bronchial CF cells, and computational studies confirmed the potential ability of novel compounds to act as potential Pqs system modulators.
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Sesquiterpenes such as leucodin and the labdane-type diterpene manool are natural compounds endowed with remarkably in vitro vasorelaxant and in vivo hypotensive activities. Given their structural similarity with the sesquiterpene lactone (+)-sclareolide, this molecule was selected as a scaffold to develop novel vasoactive agents. Functional, electrophysiology, and molecular dynamics studies were performed. The opening of the five-member lactone ring in the (+)-sclareolide provided a series of labdane-based small molecules, promoting a significant in vitro vasorelaxant effect. Electrophysiology data identified 7 as a CaV1.2 channel blocker and a KCa1.1 channel stimulator. These activities were also confirmed in the intact vascular tissue. The significant antagonism caused by the CaV1.2 channel agonist Bay K 8644 suggested that 7 might interact with the dihydropyridine binding site. Docking and molecular dynamic simulations provided the molecular basis of the CaV1.2 channel blockade and KCa1.1 channel stimulation produced by 7. Finally, 7 reduced coronary perfusion pressure and heart rate, while prolonging conduction and refractoriness of the atrioventricular node, likely because of its Ca2+ antagonism. Taken together, these data indicate that the labdane scaffold represents a valuable starting point for the development of new vasorelaxant agents endowed with negative chronotropic properties and targeting key pathways involved in the pathophysiology of hypertension and ischemic cardiomyopathy.
Assuntos
Diterpenos , Hipertensão , Sítios de Ligação , Canais de Cálcio Tipo L/metabolismo , Diterpenos/farmacologia , Humanos , Lactonas , Vasodilatadores/farmacologiaRESUMO
Histone deacetylases (HDACs) are epigenetic enzymes which participate in transcriptional repression and chromatin condensation mechanisms by removing the acetyl moiety from acetylated ε-amino group of histone lysines and other non-histone proteins. In recent years, HDAC8, a class I HDAC, has emerged as a promising target for different disorders, including X-linked intellectual disability, fibrotic diseases, cancer, and various neuropathological conditions. Selective HDAC8 targeting is required to limit side effects deriving from the treatment with pan-HDAC inhibitors (HDACis); thus, many endeavours have focused on the development of selective HDAC8is. In addition, polypharmacological approaches have been explored to achieve a synergistic action on multi-factorial diseases or to enhance the drug efficacy. In this frame, proteolysis-targeting chimeras (PROTACs) might be regarded as a dual-targeting approach for attaining HDAC8 proteasomal degradation. This review highlights the most relevant and recent advances relative to HDAC8 validation in various diseases, providing a snapshot of the current selective HDAC8is, with a focus on polyfunctional modulators.
Assuntos
Neoplasias , Proteínas Repressoras , Inibidores de Histona Desacetilases/farmacologia , Inibidores de Histona Desacetilases/uso terapêutico , Histona Desacetilases/metabolismo , Humanos , Neoplasias/tratamento farmacológico , Proteínas Repressoras/genética , Proteínas Repressoras/metabolismoRESUMO
In the field of drug discovery, the nitrile group is well represented among drugs and biologically active compounds. It can form both non-covalent and covalent interactions with diverse biological targets, and it is amenable as an electrophilic warhead for covalent inhibition. The main advantage of the nitrile group as a warhead is mainly due to its milder electrophilic character relative to other more reactive groups (e.g., -CHO), reducing the possibility of unwanted reactions that would hinder the development of safe drugs, coupled to the ease of installation through different synthetic approaches. The covalent inhibition is a well-assessed design approach for serine, threonine, and cysteine protease inhibitors. The mechanism of hydrolysis of these enzymes involves the formation of a covalent acyl intermediate, and this mechanism can be exploited by introducing electrophilic warheads in order to mimic this covalent intermediate. Due to the relevant role played by the cysteine protease in the survival and replication of infective agents, spanning from viruses to protozoan parasites, we will review the most relevant and recent examples of protease inhibitors presenting a nitrile group that have been introduced to form or to facilitate the formation of a covalent bond with the catalytic cysteine active site residue.
Assuntos
Cisteína Proteases , Doenças Parasitárias , Cisteína/química , Inibidores de Cisteína Proteinase/farmacologia , Descoberta de Drogas , Humanos , Nitrilas/farmacologiaRESUMO
The potential of natural and synthetic chalcones as therapeutic leads against different pathological conditions has been investigated for several years, and this class of compounds emerged as a privileged chemotype due to its interesting anti-inflammatory, antimicrobial, antiviral, and anticancer properties. The objective of our study was to contribute to the investigation of this class of natural products as anti-leishmanial agents. We aimed at investigating the structure-activity relationships of the natural chalcone lophirone E, characterized by the presence of benzofuran B-ring, and analogues on anti-leishmania activity. Here we describe an effective synthetic strategy for the preparation of the natural chalcone lophirone E and its application to the synthesis of a small set of chalcones bearing different substitution patterns at both the A and heterocyclic B rings. The resulting compounds were investigated for their activity against Leishmania infantum promastigotes disclosing derivatives 1 and 28a,b as those endowed with the most interesting activities (IC50 = 15.3, 27.2, 15.9 µM, respectively). The synthetic approaches here described and the early SAR investigations highlighted the potential of this class of compounds as antiparasitic hits, making this study worthy of further investigation.
Assuntos
Antiparasitários/química , Antiparasitários/farmacologia , Benzofuranos/química , Biflavonoides/síntese química , Chalconas/síntese química , Indóis/química , Biflavonoides/química , Chalconas/química , Fenômenos Químicos , Técnicas de Química Sintética , Humanos , Leishmania infantum , Estrutura Molecular , Relação Estrutura-AtividadeRESUMO
Survival and expansion of malignant B cells in chronic lymphocytic leukemia (CLL) are highly dependent both on intrinsic defects in the apoptotic machinery and on the interactions with cells and soluble factors in the lymphoid microenvironment. The adaptor protein p66Shc is a negative regulator of antigen receptor signaling, chemotaxis and apoptosis whose loss in CLL B cells contributes to their extended survival and poor prognosis. Hence, the identification of compounds that restore p66Shc expression and function in malignant B cells may pave the way to a new therapeutic approach for CLL. Here we show that a novel oxazepine-based compound (OBC-1) restores p66Shc expression in primary human CLL cells by promoting JNK-dependent STAT4 activation without affecting normal B cells. Moreover, we demonstrate that the potent pro-apoptotic activity of OBC-1 in human leukemic cells directly correlates with p66Shc expression levels and is abrogated when p66Shc is genetically deleted. Preclinical testing of OBC-1 and the novel analogue OBC-2 in Eµ-TCL1 tumor-bearing mice resulted in a significantly longer overall survival and a reduction of the tumor burden in the spleen and peritoneum. Interestingly, OBCs promote leukemic cell mobilization from the spleen to the blood, which correlates with upregulation of sphingosine-1-phosphate receptor expression. In summary, our work identifies OBCs as a promising class of compounds that, by boosting p66Shc expression through the activation of the JNK/STAT4 pathway, display dual therapeutic effects for CLL intervention, namely the ability to mobilize cells from secondary lymphoid organs and a potent pro-apoptotic activity against circulating leukemic cells.
Assuntos
Antineoplásicos/uso terapêutico , Leucemia Linfocítica Crônica de Células B/tratamento farmacológico , Oxazepinas/uso terapêutico , Animais , Antineoplásicos/farmacologia , Morte Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Feminino , Humanos , Proteínas Quinases JNK Ativadas por Mitógeno/metabolismo , Leucemia Linfocítica Crônica de Células B/metabolismo , Leucemia Linfocítica Crônica de Células B/patologia , Masculino , Camundongos Transgênicos , Oxazepinas/farmacologia , Proteínas Proto-Oncogênicas c-bcl-2/genética , Fator de Transcrição STAT4/genética , Fator de Transcrição STAT4/metabolismo , Receptores de Esfingosina-1-Fosfato/genética , Proteína 1 de Transformação que Contém Domínio 2 de Homologia de Src/genética , Proteína 1 de Transformação que Contém Domínio 2 de Homologia de Src/metabolismoRESUMO
Oral squamous cell carcinomas (OSCC) and esophageal squamous cell carcinomas (ESCC) exhibit a survival rate of less than 60% and 40%, respectively. Late-stage diagnosis and lack of effective treatment strategies make both OSCC and ESCC a significant health burden. Autophagy, a lysosome-dependent catabolic process, involves the degradation of intracellular components to maintain cell homeostasis. Targeting autophagy has been highlighted as a feasible therapeutic strategy with clinical utility in cancer treatment, although its associated regulatory mechanisms remain elusive. The detection of relevant biomarkers in biological fluids has been anticipated to facilitate early diagnosis and/or prognosis for these tumors. In this context, recent studies have indicated the presence of specific proteins and small RNAs, detectable in circulating plasma and serum, as biomarkers. Interestingly, the interplay between biomarkers (eg, exosomal microRNAs) and autophagic processes could be exploited in the quest for targeted and more effective therapies for OSCC and ESCC. In this review, we give an overview of the available biomarkers and innovative targeted therapeutic strategies, including the application of autophagy modulators in OSCC and ESCC. Additionally, we provide a viewpoint on the state of the art and on future therapeutic perspectives combining the early detection of relevant biomarkers with drug discovery for the treatment of OSCC and ESCC.
Assuntos
Autofagia/efeitos dos fármacos , Autofagia/efeitos da radiação , Neoplasias Esofágicas/tratamento farmacológico , Carcinoma de Células Escamosas do Esôfago/tratamento farmacológico , Neoplasias Bucais/tratamento farmacológico , Proteínas Quinases Ativadas por AMP/metabolismo , Consumo de Bebidas Alcoólicas , Antineoplásicos/farmacologia , Autofagossomos/metabolismo , Biomarcadores/metabolismo , Neoplasias Esofágicas/radioterapia , Carcinoma de Células Escamosas do Esôfago/radioterapia , Predisposição Genética para Doença , Humanos , Lisossomos/metabolismo , Neoplasias Bucais/radioterapia , Prognóstico , Radioterapia/métodos , Transdução de Sinais , Produtos do Tabaco , Viroses/complicaçõesRESUMO
Schistosomiasis is a neglected tropical disease mainly affecting the poorest tropical and subtropical areas of the world with the impressive number of roughly 200 million infections per year. Schistosomes are blood trematode flukes of the genus Schistosoma causing symptoms in humans and animals. Organ morbidity is caused by the accumulation of parasite eggs and subsequent development of fibrosis. If left untreated, schistosomiasis can result in substantial morbidity and even mortality. Praziquantel (PZQ) is the most effective and widely used compound for the treatment of the disease, in prevention and control programs in the last 30 years. Unfortunately, it has no effect on juvenile immature schistosomes and cannot prevent reinfection or interfere with the schistosome life cycle; moreover drug-resistance represents a serious threat. The search for an alternative or complementary treatment is urgent and drug repurposing could accelerate a solution. The anti-anginal drug perhexiline maleate (PHX) has been previously shown to be effective on larval, juvenile, and adult stages of S. mansoni and to impact egg production in vitro. Since PHX is a racemic mixture of R-(+)- and S-(-)-enantiomers, we designed and realized a stereoselective synthesis of both PHX enantiomers and developed an analytical procedure for the direct quantification of the enantiomeric excess also suitable for semipreparative separation of PHX enantiomers. We next investigated the impact of each enantiomer on viability of newly transformed schistosomula (NTS) and worm pairs of S. mansoni as well as on egg production and vitellarium morphology by in vitro studies. Our results indicate that the R-(+)-PHX is mainly driving the anti-schistosomal activity but that also the S-(-)-PHX possesses a significant activity towards S. mansoni in vitro.
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Perexilina/análogos & derivados , Schistosoma mansoni/efeitos dos fármacos , Animais , Larva , Estrutura Molecular , Perexilina/uso terapêutico , Estereoisomerismo , Relação Estrutura-AtividadeRESUMO
Histone deacetylases (HDACs) are a class of epigenetic modulators overexpressed in numerous types of cancers. Consequently, HDAC inhibitors (HDACIs) have emerged as promising antineoplastic agents. Unfortunately, the most developed HDACIs suffer from poor selectivity towards a specific isoform, limiting their clinical applicability. Among the isoforms, HDAC1 represents a crucial target for designing selective HDACIs, being aberrantly expressed in several malignancies. Accordingly, the development of a predictive in silico tool employing a large set of HDACIs (aminophenylbenzamide derivatives) is herein presented for the first time. Software Phase was used to derive a 3D-QSAR model, employing as alignment rule a common-features pharmacophore built on 20 highly active/selective HDAC1 inhibitors. The 3D-QSAR model was generated using 370 benzamide-based HDACIs, which yielded an excellent correlation coefficient value (R2 = 0.958) and a satisfactory predictive power (Q2 = 0.822; Q2F3 = 0.894). The model was validated (r2ext_ts = 0.794) using an external test set (113 compounds not used for generating the model), and by employing a decoys set and the receiver-operating characteristic (ROC) curve analysis, evaluating the Güner-Henry score (GH) and the enrichment factor (EF). The results confirmed a satisfactory predictive power of the 3D-QSAR model. This latter represents a useful filtering tool for screening large chemical databases, finding novel derivatives with improved HDAC1 inhibitory activity.
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Desenvolvimento de Medicamentos , Inibidores de Histona Desacetilases/química , Simulação de Acoplamento Molecular , Simulação de Dinâmica Molecular , Relação Quantitativa Estrutura-Atividade , Algoritmos , Simulação por Computador , Desenho de Fármacos , Inibidores de Histona Desacetilases/farmacologia , Humanos , Ligantes , Estrutura Molecular , Curva ROC , Reprodutibilidade dos TestesRESUMO
Caffeic acid and related natural compounds were previously described as Leishmania amazonensis arginase (L-ARG) inhibitors, and against the whole parasite in vitro. In this study, we tested cinnamides that were previously synthesized to target human arginase. The compound caffeic acid phenethyl amide (CAPA), a weak inhibitor of human arginase (IC50 = 60.3 ± 7.8 µM) was found to have 9-fold more potency against L-ARG (IC50 = 6.9 ± 0.7 µM). The other compounds that did not inhibit human arginase were characterized as L-ARG, showing an IC50 between 1.3-17.8 µM, and where the most active was compound 15 (IC50 = 1.3 ± 0.1 µM). All compounds were also tested against L. amazonensis promastigotes, and only the compound CAPA showed an inhibitory activity (IC50 = 80 µM). In addition, in an attempt to gain an insight into the mechanism of competitive L-ARG inhibitors, and their selectivity over mammalian enzymes, we performed an extensive computational investigation, to provide the basis for the selective inhibition of L-ARG for this series of compounds. In conclusion, our results indicated that the compounds based on cinnamoyl or 3,4-hydroxy cinnamoyl moiety could be a promising starting point for the design of potential antileishmanial drugs based on selective L-ARG inhibitors.
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Antiprotozoários/farmacologia , Arginase/antagonistas & inibidores , Cinamatos/farmacologia , Inibidores Enzimáticos/farmacologia , Leishmania/enzimologia , Proteínas de Protozoários/antagonistas & inibidores , Animais , Sítios de Ligação , Ácidos Cafeicos/química , Bovinos , Cinamatos/química , Desenho de Fármacos , Humanos , Concentração Inibidora 50 , Cinética , Ligantes , Simulação de Dinâmica Molecular , Conformação Proteica , Proteínas Recombinantes/químicaRESUMO
Despite recent advancements in its control, malaria is still a deadly parasitic disease killing millions of people each year. Progresses in combating the infection have been made by using the so-called artemisinin combination therapies (ACTs). Natural and synthetic peroxides are an important class of antimalarials. Here we describe a new series of peroxides synthesized through a new elaboration of the scaffold of bicyclic-fused/bridged synthetic endoperoxides previously developed by us. These peroxides are produced by a straightforward synthetic protocol and are characterized by submicromolar potency when tested against both chloroquine-sensitive and chloroquine-resistant Plasmodium falciparum strains. To investigate their mode of action, the biomimetic reaction of the representative compound 6w with Fe(II) was studied by EPR and the reaction products were characterized by NMR. Rationalization of the observed structure-activity relationship studies was performed by molecular docking. Taken together, our data robustly support the hypothesized mode of activation of peroxides 6a-cc and led to the definition of the key structural requirements responsible for the antiplasmodial potency. These data will pave the way in future to the rational design of novel optimized antimalarials suitable for in vivo investigation.
Assuntos
Antimaláricos/farmacologia , Materiais Biomiméticos/farmacologia , Compostos Bicíclicos com Pontes/farmacologia , Compostos Férricos/farmacologia , Plasmodium falciparum/efeitos dos fármacos , Antimaláricos/síntese química , Antimaláricos/química , Materiais Biomiméticos/síntese química , Materiais Biomiméticos/química , Compostos Bicíclicos com Pontes/síntese química , Compostos Bicíclicos com Pontes/química , Relação Dose-Resposta a Droga , Compostos Férricos/síntese química , Compostos Férricos/química , Estrutura Molecular , Testes de Sensibilidade Parasitária , Relação Estrutura-AtividadeRESUMO
Mutations in MECP2 gene have been identified in more than 95% of patients with classic Rett syndrome, one of the most common neurodevelopmental disorders in females. Taking advantage of the breakthrough technology of genetic reprogramming, we investigated transcriptome changes in neurons differentiated from induced Pluripotent Stem Cells (iPSCs) derived from patients with different mutations. Profiling by RNA-seq in terminally differentiated neurons revealed a prominent GABAergic circuit disruption along with a perturbation of cytoskeleton dynamics. In particular, in mutated neurons we identified a significant decrease of acetylated α-tubulin which can be reverted by treatment with selective inhibitors of HDAC6, the main α-tubulin deacetylase. These findings contribute to shed light on Rett pathogenic mechanisms and provide hints for the treatment of Rett-associated epileptic behavior as well as for the definition of new therapeutic strategies for Rett syndrome.
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Neurônios GABAérgicos/metabolismo , Neurônios GABAérgicos/fisiologia , Desacetilase 6 de Histona/metabolismo , Células-Tronco Pluripotentes Induzidas/fisiologia , Síndrome de Rett/metabolismo , Síndrome de Rett/fisiopatologia , Tubulina (Proteína)/metabolismo , Acetilação , Diferenciação Celular/fisiologia , Feminino , Humanos , MasculinoRESUMO
Tuberculosis (TB) is one of the top 10 causes of death worldwide. This scenario is further complicated by the insurgence of multidrug-resistant (MDR) and extensively drug-resistant (XDR) TB. The identification of appropriate drugs with multi-target affinity profiles is considered to be a widely accepted strategy to overcome the rapid development of resistance. The aim of this study was to discover Food and Drug Administration (FDA)-approved drugs possessing antimycobacterial activity, potentially coupled to an effective multi-target profile. An integrated screening platform was implemented based on computational procedures (high-throughput docking techniques on the target enzymes peptide deformylase and Zmp1) and in vitro phenotypic screening assays using two models to evaluate the activity of the selected drugs against Mycobacterium tuberculosis (Mtb), namely, growth of Mtb H37Rv and of two clinical isolates in axenic media, and infection of peripheral blood mononuclear cells with Mtb. Starting from over 3000 FDA-approved drugs, we selected 29 marketed drugs for submission to biological evaluation. Out of 29 drugs selected, 20 showed antimycobacterial activity. Further characterization suggested that five drugs possessed promising profiles for further studies. Following a repurposing strategy, by combining computational and biological efforts, we identified marketed drugs with relevant antimycobacterial profiles.
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Antituberculosos , Reposicionamento de Medicamentos , Leucócitos Mononucleares/microbiologia , Mycobacterium tuberculosis/crescimento & desenvolvimento , Tuberculose/tratamento farmacológico , Antituberculosos/química , Antituberculosos/farmacologia , Aprovação de Drogas , Avaliação Pré-Clínica de Medicamentos , Humanos , Leucócitos Mononucleares/metabolismo , Leucócitos Mononucleares/patologia , Tuberculose/metabolismo , Tuberculose/patologiaRESUMO
Neuroblastoma, a paediatric malignancy of the sympathetic nervous system, accounts for 15 % of childhood cancer deaths. Despite advances in understanding the biology, it remains one of the most difficult paediatric cancers to treat partly due to the development of multidrug resistance. There is thus a compelling demand for new treatment strategies that can bypass resistance mechanisms. The pyrrolo-1,5-benzoxazepine (PBOX) compounds are a series of novel microtubule-targeting agents that potently induce apoptosis in various tumour models. We have previously reported that PBOX compounds induce apoptosis in drug sensitive and multidrug resistant neuroblastoma cells and synergistically enhance apoptosis induced by chemotherapeutics such as carboplatin. In this study we present further data concerning the molecular basis of PBOX-induced apoptosis in neuroblastoma. We demonstrate that PBOX-6 induced AMP-activated protein kinase (AMPK) activation and downstream acetyl-CoA carboxylase phosphorylation. Increased reactive oxygen species (ROS) appeared to serve as the upstream signal for AMPK activation as pretreatment of cells with the antioxidant N-acetylcysteine inhibited both AMPK activation and PBOX-induced apoptosis. Furthermore, activation of AMPK by PBOX-6 was found to inhibit mTOR complex 1 (mTORC1) signalling. Finally, we demonstrate the efficacy of PBOX-6 in an in vivo xenograft model of neuroblastoma. This study provides new insights into understanding the molecular and cellular mechanisms involved in PBOX-induced cell death in neuroblastoma and further supports their future use as novel anti-cancer agents for the treatment of neuroblastoma.