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Key epitranscriptomic players have been increasingly characterized for their structural features and their involvement in several diseases. Accordingly, the design and synthesis of novel epitranscriptomic modulators have started opening a glimmer for drug discovery. m6A is a reversible modification occurring on a specific site and is catalyzed by three sets of proteins responsible for opposite functions. Writers (e.g., methyl-transferase-like protein (METTL) 3/METTL14 complex and METTL16) introduce the methyl group on adenosine N-6, by transferring the methyl group from the methyl donor S-adenosyl-methionine (SAM) to the substrate. Despite the rapidly advancing drug discovery progress on METTL3/METTL14, the METTL16 m6A writer has been marginally explored so far. We herein provide the first comprehensive overview of structural and biological features of METTL16, highlighting the state of the art in the field of its biological and structural characterization. We also showcase initial efforts in the identification of structural templates and preliminary structure-activity relationships for METTL16 modulators.
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A series of benzoxazole-based amides and sulfonamides were synthesized and evaluated for their human peroxisome proliferator-activated receptor (PPAR)α and PPARγ activity. All tested compounds showed a dual antagonist profile on both PPAR subtypes; based on transactivation results, seven compounds were selected to test their in vitro antiproliferative activity in a panel of eight cancer cell lines with different expression rates of PPARα and PPARγ. 3f was identified as the most cytotoxic compound, with higher potency in the colorectal cancer cell lines HT-29 and HCT116. Compound 3f induced a concentration-dependent activation of caspases and cell-cycle arrest in both colorectal cancer models. Docking experiments were also performed to shed light on the putative binding mode of this novel class of dual PPARα/γ antagonists.
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SARS-CoV-2 caused worldwide the current outbreak called COVID-19. Despite multiple countermeasures implemented, there is an urgent global need for new potent and efficient antiviral drugs against this pathogen. In this context, the main protease (Mpro) of SARS-CoV-2 is an essential viral enzyme and plays a pivotal role in viral replication and transcription. Its specific cleavage of polypeptides after a glutamine residue has been considered as a key element to design novel antiviral drugs. Herein, we reported the design, synthesis and structure-activity relationships of novel α-ketoamides as covalent reversible inhibitors of Mpro, exploiting the PADAM oxidation route. The reported compounds showed µM to nM activities in enzymatic and in the antiviral cell-based assays against SARS-CoV-2 Mpro. In order to assess inhibitors' binding mode, two co-crystal structures of SARS-CoV-2 Mpro in complex with our inhibitors were solved, which confirmed the covalent binding of the keto amide moiety to the catalytic Cys145 residue of Mpro. Finally, in order to interrogate potential broad-spectrum properties, we assessed a selection of compounds against MERS Mpro where they showed nM inhibitory potency, thus highlighting their potential as broad-spectrum coronavirus inhibitors.
Assuntos
Tratamento Farmacológico da COVID-19 , SARS-CoV-2 , Humanos , Proteases 3C de Coronavírus , Inibidores de Proteases/farmacologia , Inibidores de Proteases/química , Proteínas não Estruturais Virais , Cisteína Endopeptidases/metabolismo , Antivirais/farmacologia , Antivirais/química , Simulação de Acoplamento MolecularRESUMO
Human nucleolin (hNcl) is a multifunctional protein involved in the progression of various cancers and plays a key role in other pathologies. Therefore, there is still unsatisfied demand for hNcl modulators. Recently, we demonstrated that the plant ent-kaurane diterpene oridonin inhibits hNcl but, unfortunately, this compound is quite toxic for healthy cells. Trachylobane diterpene 6,19-dihydroxy-ent-trachiloban-17-oic acid (compound 12) extracted from Psiadia punctulata (DC.) Vatke (Asteraceae) emerged as a ligand of hNcl from a cellular thermal shift assay (CETSA)-based screening of a small library of diterpenes. Effective interaction between this compound and the protein was demonstrated to occur both in vitro and inside two different types of cancer cells. Based on the experimental and computational data, a model of the hNcl/compound 12 complex was built. Because of this binding, hNcl mRNA chaperone activity was significantly reduced, and the level of phosphorylation of the protein was affected. At the biological level, cancer cell incubation with compound 12 produced a cell cycle block in the subG0/G1 phase and induced early apoptosis, whereas no cytotoxicity towards healthy cells was observed. Overall, these results suggested that 6,19-dihydroxy-ent-trachiloban-17-oic could represent a selective antitumoral agent and a promising lead for designing innovative hNcl inhibitors also usable for therapeutic purposes.
Assuntos
Asteraceae , Diterpenos do Tipo Caurano , Diterpenos , Neoplasias , Asteraceae/química , Diterpenos/química , Diterpenos/farmacologia , Diterpenos do Tipo Caurano/química , Diterpenos do Tipo Caurano/farmacologia , Humanos , Ligantes , Neoplasias/tratamento farmacológico , Fosfoproteínas , Fosforilação , RNA Mensageiro , Proteínas de Ligação a RNA , NucleolinaRESUMO
Insulin resistance is a major pathophysiological feature in the development of type 2 diabetes (T2DM). Ferulic acid is known for attenuating the insulin resistance and reducing the blood glucose in T2DM rats. In this work, we designed and synthesized a library of new ferulic acid amides (FAA), which could be considered as ring opening derivatives of the antidiabetic PPARγ agonists Thiazolidinediones (TZDs). However, since these compounds displayed weak PPAR transactivation capacity, we employed a proteomics approach to unravel their molecular target(s) and identified the peroxiredoxin 1 (PRDX1) as a direct binding target of FAAs. Interestingly, PRDX1, a protein with antioxidant and chaperone activity, has been implied in the development of T2DM by inducing hepatic insulin resistance. SPR, mass spectrometry-based studies, docking experiments and inâ vitro inhibition assay confirmed that compounds VIe and VIf bound PRDX1 and induced a dose-dependent inhibition. Furthermore, VIe and VIf significantly improved hyperglycemia and hyperlipidemia in streptozotocin-nicotinamide (STZ-NA)-induced diabetic rats as confirmed by histopathological examinations. These results provide guidance for developing the current FAAs as new potential antidiabetic agents.
Assuntos
Amidas/farmacologia , Ácidos Cumáricos/farmacologia , Inibidores Enzimáticos/farmacologia , Hipoglicemiantes/farmacologia , Hipolipemiantes/farmacologia , Peroxirredoxinas/antagonistas & inibidores , Amidas/síntese química , Amidas/química , Animais , Compostos de Bifenilo/antagonistas & inibidores , Sobrevivência Celular/efeitos dos fármacos , Ácidos Cumáricos/síntese química , Ácidos Cumáricos/química , Diabetes Mellitus Experimental/induzido quimicamente , Diabetes Mellitus Experimental/tratamento farmacológico , Diabetes Mellitus Experimental/metabolismo , Relação Dose-Resposta a Droga , Inibidores Enzimáticos/síntese química , Inibidores Enzimáticos/química , Humanos , Hipoglicemia/induzido quimicamente , Hipoglicemia/tratamento farmacológico , Hipoglicemia/metabolismo , Hipoglicemiantes/síntese química , Hipoglicemiantes/química , Hipolipemiantes/síntese química , Hipolipemiantes/química , Masculino , Modelos Moleculares , Estrutura Molecular , Peroxirredoxinas/metabolismo , Picratos/antagonistas & inibidores , Ratos , Ratos Sprague-Dawley , Ratos Wistar , Estreptozocina , Relação Estrutura-Atividade , Células Tumorais CultivadasRESUMO
Given the enormous social and health impact of the pandemic triggered by severe acute respiratory syndrome 2 (SARS-CoV-2), the scientific community made a huge effort to provide an immediate response to the challenges posed by Coronavirus disease 2019 (COVID-19). One of the most important proteins of the virus is an enzyme, called 3CLpro or main protease, already identified as an important pharmacological target also in SARS and Middle East respiratory syndrome virus (MERS) viruses. This protein triggers the production of a whole series of enzymes necessary for the virus to carry out its replicating and infectious activities. Therefore, it is crucial to gain a deeper understanding of 3CLpro structure and function in order to effectively target this enzyme. All-atoms molecular dynamics (MD) simulations were performed to examine the different conformational behaviors of the monomeric and dimeric form of SARS-CoV-2 3CLpro apo structure, as revealed by microsecond time scale MD simulations. Our results also shed light on the conformational dynamics of the loop regions at the entry of the catalytic site. Studying, at atomic level, the characteristics of the active site and obtaining information on how the protein can interact with its substrates will allow the design of molecules able to block the enzymatic function crucial for the virus.
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Betacoronavirus/metabolismo , Cisteína Endopeptidases/química , Cisteína Endopeptidases/metabolismo , Proteínas não Estruturais Virais/química , Proteínas não Estruturais Virais/metabolismo , Betacoronavirus/química , Domínio Catalítico , Proteases 3C de Coronavírus , Humanos , Modelos Moleculares , Simulação de Dinâmica Molecular , Ligação Proteica , Conformação Proteica , Multimerização Proteica , SARS-CoV-2RESUMO
An agonist-antagonist switching strategy was performed to discover novel PPARα antagonists. Phenyldiazenyl derivatives of fibrates were developed, bearing sulfonimide or amide functional groups. A second series of compounds was synthesized, replacing the phenyldiazenyl moiety with amide or urea portions. Final compounds were screened by transactivation assay, showing good PPARα antagonism and selectivity at submicromolar concentrations. When tested in cancer cell models expressing PPARα, selected derivatives induced marked effects on cell viability. Notably, 3c, 3d, and 10e displayed remarkable antiproliferative effects in two paraganglioma cell lines, with CC50 lower than commercial PPARα antagonist GW6471 and a negligible toxicity on normal fibroblast cells. Docking studies were also performed to elucidate the binding mode of these compounds and to help interpretation of SAR data.
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Amyloid precursor protein (APP) is processed along both the nonamyloidogenic pathway preventing amyloid beta peptide (Aß) production and the amyloidogenic pathway, generating Aß, whose accumulation characterizes Alzheimer's disease. Items of evidence report that the intracellular trafficking plays a key role in the generation of Aß and that the 37/67 kDa LR (laminin receptor), acting as a receptor for Aß, may mediate Aß-pathogenicity. Moreover, findings indicating interaction between the receptor and the key enzymes involved in the amyloidogenic pathway suggest a strong link between 37/67 kDa LR and APP processing. We show herein that the specific 37/67 kDa LR inhibitor, NSC48478, is able to reversibly affect the maturation of APP in a pH-dependent manner, resulting in the partial accumulation of the immature APP isoforms (unglycosylated/acetylated forms) in the endoplasmic reticulum (ER) and in transferrin-positive recycling endosomes, indicating alteration of the APP intracellular trafficking. These effects reveal NSC48478 inhibitor as a novel small molecule to be tested in disease conditions, mediated by the 37/67 kDa LR and accompanied by inactivation of ERK1/2 (extracellular signal-regulated kinases) signalling and activation of Akt (serine/threonine protein kinase) with consequent inhibition of GSK3ß.
Assuntos
Doença de Alzheimer/metabolismo , Precursor de Proteína beta-Amiloide/metabolismo , Naftóis/farmacologia , Neurônios/metabolismo , Receptores de Laminina/antagonistas & inibidores , Proteínas Ribossômicas/antagonistas & inibidores , Animais , Linhagem Celular Tumoral , Retículo Endoplasmático/metabolismo , Endossomos/efeitos dos fármacos , Glicosilação , Complexo de Golgi/efeitos dos fármacos , Células HeLa , Humanos , Concentração de Íons de Hidrogênio , Concentração Inibidora 50 , Laminina , Camundongos , Microscopia de Fluorescência , Proteínas Priônicas , Processamento de Proteína Pós-Traducional , Transporte Proteico , RNA Interferente Pequeno/metabolismo , Transdução de SinaisRESUMO
A series of l-lysine-conjugated pyridophenoxazinones 2-5 and 2'-5' were designed and synthesized for developing compounds with multimodal anticancer potentialities. All compounds inhibited the proliferation of a panel of human liquid and solid neoplastic cell lines. 2 and 5 were the most active compounds with IC50 values in the submicromolar range. UV-vis, 1H NMR, unwinding, and docking experiments demonstrated that they intercalate between the middle 5'-GC-3' base pairs with the carboxamide side chain lying into major groove. Charge-transfer contribution to the complex stability, evaluated by ab initio calculations, was found to correlate with cytotoxicity. Relaxation and cleavage assays showed that 2 and 5 selectively target Topo IIα over Topo IIß and stimulate the formation of covalent Topo II-DNA complexes, functioning as poisons. Moreover, compound 5 induced DNA damage and arrested MCF-7 cells at the G2/M phase. Altogether, the work provides interesting structure-activity relationships in the pyridophenoxazinone-l-lysine conjugate series and identifies 5 as a promising candidate for further in vivo evaluation.
Assuntos
Antineoplásicos/farmacologia , DNA Topoisomerases Tipo II/metabolismo , DNA de Neoplasias/efeitos dos fármacos , Lisina/farmacologia , Oxazinas/farmacologia , Inibidores da Topoisomerase II/farmacologia , Antineoplásicos/síntese química , Antineoplásicos/química , Sítios de Ligação/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Ligantes , Modelos Lineares , Lisina/química , Modelos Moleculares , Estrutura Molecular , Oxazinas/química , Relação Estrutura-Atividade , Inibidores da Topoisomerase II/síntese química , Inibidores da Topoisomerase II/químicaRESUMO
CDC25 phosphatases play a critical role in the regulation of the cell cycle and thus represent attractive cancer therapeutic targets. We previously discovered the 4-(2-carboxybenzoyl)phthalic acid (NSC28620) as a new CDC25 inhibitor endowed with promising anticancer activity in breast, prostate, and leukemia cells. Herein, we report a structure-based optimization of NSC28620, leading to the identification of a series of novel naphthylphenylketone and naphthylphenylamine derivatives as CDC25B inhibitors. Compounds 7j, 7i, 6e, 7f, and 3 showed higher inhibitory activity than the initial lead, with Ki values in the low micromolar range. Kinetic analysis, intrinsic fluorescence studies, and induced fit docking simulations provided a mechanistic understanding of the activity of these derivatives. All compounds were tested in the highly aggressive human melanoma cell lines A2058 and A375. Compound 4a potently inhibited cell proliferation and colony formation, causing an increase of the G2/M phase and a reduction of the G0/G1 phase of the cell cycle in both cell lines.
Assuntos
Compostos de Anilina/síntese química , Antineoplásicos/síntese química , Desenho de Fármacos , Descoberta de Drogas/métodos , Cetonas/síntese química , Fosfatases cdc25/antagonistas & inibidores , Compostos de Anilina/farmacologia , Compostos de Anilina/uso terapêutico , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/fisiologia , Inibidores Enzimáticos/síntese química , Inibidores Enzimáticos/uso terapêutico , Humanos , Cetonas/farmacologia , Cetonas/uso terapêutico , Melanoma/tratamento farmacológico , Estrutura Terciária de Proteína , Resultado do TratamentoRESUMO
Peroxisome Proliferator-Activated Receptor γ (PPARγ) is an important sensor at the crossroad of diabetes, obesity, immunity and cancer as it regulates adipogenesis, metabolism, inflammation and proliferation. PPARγ exerts its pleiotropic functions upon binding of natural or synthetic ligands. The molecular mechanisms through which PPARγ controls cancer initiation/progression depend on the different mode of binding of distinctive ligands. Here, we analyzed a series of chiral phenoxyacetic acid analogues for their ability to inhibit colorectal cancer (CRC) cells growth by binding PPARγ as partial agonists as assessed in transactivation assays of a PPARG-reporter gene. We further investigated compounds (R,S)-3, (S)-3 and (R,S)-7 because they combine the best antiproliferative activity and a limited transactivation potential and found that they induce cell cycle arrest mainly via upregulation of p21waf1/cip1. Interestingly, they also counteract the ß-catenin/TCF pathway by repressing c-Myc and cyclin D1, supporting their antiproliferative effect. Docking experiments provided insight into the binding mode of the most active compound (S)-3, suggesting that its partial agonism could be related to a better stabilization of H3 rather than H11 and H12. In conclusion, we identified a series of PPARγ partial agonists affecting distinct pathways all leading to strong antiproliferative effects. These findings may pave the way for novel therapeutic strategies in CRC.
Assuntos
Acetatos/farmacologia , Proliferação de Células/efeitos dos fármacos , Neoplasias do Colo/patologia , PPAR gama/agonistas , Acetatos/química , Ciclo Celular/efeitos dos fármacos , Células HEK293 , Células HT29 , Humanos , Simulação de Acoplamento Molecular , PPAR gama/química , PPAR gama/genética , EstereoisomerismoRESUMO
Cardiovascular disease is the major cause of death globally, with hypercholesterolemia being an important risk factor. The PCSK9 represents an attractive therapeutic target for hypercholesterolemia treatment and is currently in the spotlight of the scientific community. After autocatalytic activation in the hepatocyte endoplasmic reticulum, this convertase binds to the LDLR and channels it to the degradation pathway. This review gives an overview on the latest developments in the inhibition of PCSK9, including disruption of the protein-protein interaction (PPI) between PCSK9 and LDLR by peptidomimetics, adnectins and monoclonal antibodies and the suppression of PCSK9 expression by small molecules, siRNA and genome editing techniques. In addition, we discuss alternative approaches, such as anti-PCSK9 active vaccination and heparin mimetics.
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Inibidores Enzimáticos/química , Hipercolesterolemia/tratamento farmacológico , Pró-Proteína Convertase 9/genética , Pró-Proteína Convertase 9/metabolismo , Animais , Anticorpos Monoclonais/metabolismo , Produtos Biológicos/química , Produtos Biológicos/farmacologia , Descoberta de Drogas/métodos , Retículo Endoplasmático/metabolismo , Inibidores Enzimáticos/farmacologia , Fibronectinas/química , Edição de Genes/métodos , Regulação da Expressão Gênica/efeitos dos fármacos , Hepatócitos/metabolismo , Humanos , Hipercolesterolemia/metabolismo , Peptídeos/química , Peptídeos/farmacologia , Peptidomiméticos/metabolismo , Conformação Proteica , RNA Interferente Pequeno/metabolismo , Receptores de LDL/metabolismo , Transdução de SinaisRESUMO
The development of immunoproteasome-selective inhibitors is a promising strategy for treating hematologic malignancies, autoimmune and inflammatory diseases. In this context, we report the design, synthesis, and biological evaluation of a new series of amide derivatives as immunoproteasome inhibitors. Notably, the designed compounds act as noncovalent inhibitors, which might be a promising therapeutic option because of the lack of drawbacks and side effects associated with irreversible inhibition. Among the synthesized compounds, we identified a panel of active inhibitors with Ki values in the low micromolar or sub-micromolar ranges toward the ß5i and/or ß1i subunits of immunoproteasomes. One of the active compounds was shown to be the most potent and selective inhibitor with a Ki value of 21â nm against the single ß1i subunit. Docking studies allowed us to determine the mode of binding of the molecules in the catalytic site of immunoproteasome subunits.
Assuntos
Amidas/química , Complexo de Endopeptidases do Proteassoma/metabolismo , Inibidores de Proteassoma/química , Amidas/síntese química , Amidas/metabolismo , Doenças Autoimunes/imunologia , Doenças Autoimunes/metabolismo , Doenças Autoimunes/patologia , Sítios de Ligação , Domínio Catalítico , Humanos , Simulação de Acoplamento Molecular , Complexo de Endopeptidases do Proteassoma/química , Inibidores de Proteassoma/síntese química , Inibidores de Proteassoma/metabolismo , Subunidades Proteicas/antagonistas & inibidores , Subunidades Proteicas/metabolismo , Relação Estrutura-AtividadeRESUMO
A new series of derivatives of the PPARα/γ dual agonist 1 allowed us to identify the ligand ( S)-6 as a potent partial agonist of both PPARα and γ subtypes. X-ray studies in PPARγ revealed two different binding modes of ( S)-6 to the canonical site. However, ( S)-6 was also able to bind an alternative site as demonstrated by transactivation assay in the presence of a canonical PPARγ antagonist and supported from docking experiments. This compound did not activate the PPARγ-dependent program of adipocyte differentiation inducing a very less severe lipid accumulation compared to rosiglitazone but increased the insulin-stimulated glucose uptake in 3T3-L1 adipocytes. Finally, ( S)-6 inhibited the Cdk5-mediated phosphorylation of PPARγ at serine 273 that is currently considered the mechanism by which some PPARγ partial agonists exert antidiabetic effects similar to thiazolidinediones, without showing their typical side effects. This is the first PPARα/γ dual agonist reported to show this inhibitory effect representing the potential lead of a new class of drugs for treatment of dyslipidemic type 2 diabetes.
Assuntos
Quinase 5 Dependente de Ciclina/antagonistas & inibidores , Descoberta de Drogas , Inibidores Enzimáticos/química , Inibidores Enzimáticos/farmacologia , PPAR alfa/antagonistas & inibidores , PPAR gama/agonistas , PPAR gama/metabolismo , Propionatos/química , Propionatos/farmacologia , Células 3T3-L1 , Animais , Cristalografia por Raios X , Quinase 5 Dependente de Ciclina/química , Células Hep G2 , Humanos , Camundongos , Modelos Moleculares , Estrutura Molecular , Fosforilação , Conformação Proteica , Relação Estrutura-AtividadeRESUMO
Structural determinants of affinity of N6-substituted-5'-C-(ethyltetrazol-2-yl)adenosine and 2-chloroadenosine derivatives at adenosine receptor (AR) subtypes were studied with binding and molecular modeling. Small N6-cycloalkyl and 3-halobenzyl groups furnished potent dual acting A1AR agonists and A3AR antagonists. 4 was the most potent dual acting human (h) A1AR agonist (Ki = 0.45 nM) and A3AR antagonist (Ki = 0.31 nM) and highly selective versus A2A; 11 and 26 were most potent at both h and rat (r) A3AR. All N6-substituted-5'-C-(ethyltetrazol-2-yl)adenosine derivatives proved to be antagonists at hA3AR but agonists at the rA3AR. Analgesia of 11, 22, and 26 was evaluated in the mouse formalin test (A3AR antagonist blocked and A3AR agonist strongly potentiated). N6-Methyl-5'-C-(ethyltetrazol-2-yl)adenosine (22) was most potent, inhibiting both phases, as observed combining A1AR and A3AR agonists. This study demonstrated for the first time the advantages of a single molecule activating two AR pathways both leading to benefit in this acute pain model.
Assuntos
Adenosina/análogos & derivados , Adenosina/farmacologia , Analgésicos/química , Analgésicos/farmacologia , Agonistas do Receptor Purinérgico P1/química , Agonistas do Receptor Purinérgico P1/farmacologia , Antagonistas de Receptores Purinérgicos P1/química , Antagonistas de Receptores Purinérgicos P1/farmacologia , Dor Aguda/tratamento farmacológico , Adenosina/uso terapêutico , Agonistas do Receptor A1 de Adenosina/química , Agonistas do Receptor A1 de Adenosina/farmacologia , Agonistas do Receptor A1 de Adenosina/uso terapêutico , Antagonistas do Receptor A3 de Adenosina/química , Antagonistas do Receptor A3 de Adenosina/farmacologia , Antagonistas do Receptor A3 de Adenosina/uso terapêutico , Analgésicos/uso terapêutico , Animais , Humanos , Camundongos , Modelos Moleculares , Agonistas do Receptor Purinérgico P1/uso terapêutico , Antagonistas de Receptores Purinérgicos P1/uso terapêutico , Receptor A1 de Adenosina/metabolismo , Receptor A3 de Adenosina/metabolismo , Receptores Purinérgicos P1/metabolismoRESUMO
Malignant melanoma is the most aggressive and life-threatening skin cancer. Melanoma develops in melanocytes and is characterized by a very high tendency to spread to other parts of the body. Its pathogenesis depends on DNA mutations leading to the activation of oncogenes or to the inactivation of suppressor genes. The identification of misregulations in intracellular signal transduction pathways has provided an opportunity for the development of mutation-specific inhibitors, which specifically target the mutated signaling cascades. Over the last few years, clinical trials with MAPK pathway inhibitors have shown significant clinical activity in melanoma; however, their efficacy is limited due to the onset of acquired resistance. This has prompted a large set of preclinical studies looking at new approaches of pathway- or target-specific inhibitors. This review gives an overview of the latest developments of small molecule targeting multiple molecular pathways in both preclinical and clinical melanoma settings, with particular emphasis on additional strategies to tackle the reduced responsiveness to inhibitor treatment as possible future directions.
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Antineoplásicos/farmacologia , Melanoma/tratamento farmacológico , Melanoma/enzimologia , Proteínas Quinases Ativadas por Mitógeno/antagonistas & inibidores , Inibidores de Proteínas Quinases/farmacologia , Bibliotecas de Moléculas Pequenas/farmacologia , Antineoplásicos/síntese química , Antineoplásicos/química , Humanos , Melanoma/patologia , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Inibidores de Proteínas Quinases/síntese química , Inibidores de Proteínas Quinases/química , Bibliotecas de Moléculas Pequenas/síntese química , Bibliotecas de Moléculas Pequenas/químicaRESUMO
We screened a short series of new chiral diphenylmethane derivatives and identified potent dual PPARα/γ partial agonists. As both enantiomers of the most active compound 1 displayed an unexpected similar transactivation activity, we performed docking experiments to provide a molecular understanding of their similar partial agonism. We also evaluated the ability of both enantiomers of 1 and racemic 2 to inhibit colorectal cancer cells proliferation: (S)-1 displayed a more robust activity due, at least in part, to a partial inhibition of the Wnt/ß-catenin signalling pathway that is upregulated in the majority of colorectal cancers. Finally, we investigated the effects of (R)-1, (S)-1 and (R,S)-2 on mitochondrial function and demonstrated that they activate the carnitine shuttle system through upregulation of carnitine/acylcarnitine carrier (CAC) and carnitine-palmitoyl-transferase 1 (CPT1) genes. Consistent with the notion that these are PPARα target genes, we tested and found that PPARα itself is regulated by a positive loop. Moreover, these compounds induced a significant mitochondrial biogenesis. In conclusion, we identified a new series of dual PPARα/γ agonists endowed with novel anti-proliferative properties associated with a strong activation of mitochondrial functions and biogenesis, a potential therapeutic target of the treatment of insulin resistance.
Assuntos
Antineoplásicos/química , Antineoplásicos/farmacologia , Compostos Benzidrílicos/química , Compostos Benzidrílicos/farmacologia , Mitocôndrias/efeitos dos fármacos , PPAR alfa/agonistas , PPAR gama/agonistas , Antineoplásicos/síntese química , Antineoplásicos/metabolismo , Compostos Benzidrílicos/síntese química , Compostos Benzidrílicos/metabolismo , Carnitina/metabolismo , Proliferação de Células/efeitos dos fármacos , Avaliação Pré-Clínica de Medicamentos , Células HT29 , Células Hep G2 , Humanos , Resistência à Insulina , Mitocôndrias/metabolismo , Simulação de Acoplamento Molecular , PPAR alfa/química , PPAR alfa/metabolismo , PPAR gama/química , PPAR gama/metabolismo , Conformação Proteica , Transdução de Sinais/efeitos dos fármacos , beta Catenina/metabolismoRESUMO
The peroxisome proliferator-activated receptors (PPARs) are nuclear receptors involved in the regulation of the metabolic homeostasis and therefore represent valuable therapeutic targets for the treatment of metabolic diseases. The development of more balanced drugs interacting with PPARs, devoid of the side-effects showed by the currently marketed PPARγ full agonists, is considered the major challenge for the pharmaceutical companies. Here we present a structure-based virtual screening approach that let us identify a novel PPAR pan-agonist with a very attractive activity profile and its crystal structure in the complex with PPARα and PPARγ, respectively. In PPARα this ligand occupies a new pocket whose filling is allowed by the ligand-induced switching of the F273 side chain from a closed to an open conformation. The comparison between this pocket and the corresponding cavity in PPARγ provides a rationale for the different activation of the ligand towards PPARα and PPARγ, suggesting a novel basis for ligand design.
Assuntos
Avaliação Pré-Clínica de Medicamentos/métodos , Naftalenos/química , Naftalenos/farmacologia , PPAR alfa/química , PPAR alfa/metabolismo , Sítios de Ligação , Varredura Diferencial de Calorimetria , Cristalografia por Raios X , Células Hep G2 , Humanos , Ligantes , Simulação de Acoplamento Molecular , PPAR alfa/agonistas , PPAR gama/agonistas , PPAR gama/metabolismo , Conformação Proteica , Pirimidinas/farmacologia , Relação Estrutura-AtividadeRESUMO
Cladosporols are secondary metabolites from Cladosporium tenuissimum characterized for their ability to control cell proliferation. We previously showed that cladosporol A inhibits proliferation of human colon cancer cells through a PPARγ-mediated modulation of gene expression. In this work, we investigated cladosporol B, an oxidate form of cladosporol A, and demonstrate that it is more efficient in inhibiting HT-29 cell proliferation due to a robust G0/G1-phase arrest and p21(waf1/cip1) overexpression. Cladosporol B acts as a PPARγ partial agonist with lower affinity and reduced transactivation potential in transient transfections as compared to the full agonists cladosporol A and rosiglitazone. Site-specific PPARγ mutants and surface plasmon resonance (SPR) experiments confirm these conclusions. Cladosporol B in addition displays a sustained proapoptotic activity also validated by p21(waf1/cip1) expression analysis in the presence of the selective PPARγ inhibitor GW9662. In the DMSO/H2O system, cladosporols A and B are unstable and convert to the ring-opened compounds 2A and 2B. Finally, docking experiments provide the structural basis for full and partial PPARγ agonism of 2A and 2B, respectively. In summary, we report here, for the first time, the structural characteristics of the binding of cladosporols, two natural molecules, to PPARγ. The binding of compound 2B is endowed with a lower transactivation potential, higher antiproliferative and proapoptotic activity than the two full agonists as compound 2A and rosiglitazone (RGZ).
Assuntos
Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Naftóis/farmacologia , PPAR gama/agonistas , Anilidas/farmacologia , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Inibidor de Quinase Dependente de Ciclina p21/metabolismo , Agonismo Parcial de Drogas , Pontos de Checagem da Fase G1 do Ciclo Celular , Células HEK293 , Humanos , Ligantes , Simulação de Acoplamento Molecular , Estresse Oxidativo , PPAR gama/antagonistas & inibidores , PPAR gama/genética , PPAR gama/metabolismo , Ligação Proteica , Conformação Proteica , Estereoisomerismo , Relação Estrutura-Atividade , Ativação TranscricionalRESUMO
Polypharmacology, a new paradigm in drug discovery that focuses on multi-target drugs (MTDs), has potential application for drug repurposing, the process of finding new uses for existing approved drugs, prediction of off-target toxicities and rational design of MTDs. In this scenario, computational strategies have demonstrated great potential in predicting polypharmacology and in facilitating drug repurposing. Here, we provide a comprehensive overview of various computational approaches that enable the prediction and analysis of in vitro and in vivo drug-response phenotypes and outline their potential for drug discovery. We give an outlook on the latest advances in rational design of MTDs and discuss possible future directions of algorithm development in this field.