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1.
Bioorg Med Chem ; 24(21): 5357-5367, 2016 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-27647370

RESUMO

The quinolinone skeleton has been utilized to develop various mechanism-based immune modulators. However, the effects of quinolinone derivatives on the release of T cell-associated interleukin-2 (IL-2) have not been established. In this study, a series of novel quinolinone derivatives was synthesized, and their immunosuppressive activity was evaluated by measuring suppression of IL-2 release from activated Jurkat T cells. Optimizing the three side chains around the quinolinone skeleton revealed the most active compound: 11l. This compound exhibits potent inhibitory activity toward IL-2 release in both 12-o-tetradecanoylphorbol-13-acetate (PMA)/A23187 (ionomycin) (IC50=80±10nM) and anti-CD3/CD28-stimulated Jurkat T cells (83% inhibition at 10µM) without cytotoxic effects. Further investigation into the underlying mechanism of 11l indicated the suppression of NF-κB and nuclear factor of activated T cells (NFAT) promoter activities in Jurkat T cells.


Assuntos
Descoberta de Drogas , Interleucina-2/antagonistas & inibidores , Quinolonas/farmacologia , Relação Dose-Resposta a Droga , Humanos , Interleucina-2/metabolismo , Células Jurkat , Estrutura Molecular , Quinolonas/síntese química , Quinolonas/química , Relação Estrutura-Atividade
2.
Bioorg Med Chem ; 24(21): 5036-5046, 2016 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-27555284

RESUMO

Members of the Janus kinase (JAK) family are potential therapeutic targets. Abnormal signaling by mutant JAK2 is related to hematological malignancy, such as myeloproliferative neoplasms (MPNs), and tyrosine kinase inhibitor (TKI)-resistance in non-small cell lung cancer (NSCLC). We discovered a potent and highly selective inhibitor of JAK2 over JAK1 and -3 based on the structure of 4-(2,5-triazole)-pyrrolopyrimidine. Among all triazole compounds tested, 2,5-triazole regioisomers more effectively inhibited JAK2 kinase activity than isomers with substitutions of various alkyl groups at the R2 position, except for methyl-substituted 1,5-triazole, which was more potent than the corresponding 1,4- and 2,5-triazoles. None of the synthesized 1,4-isomers inhibited all three JAK family members. Compounds with phenyl or tolyl group substituents at the R1 position were completely inactive compared with the corresponding analogues with a methyl substituted at the R1 position. As a result of this structure-activity relationship, 54, which is substituted with a cyclopropylmethyl moiety, exhibited significant inhibitory activity and selectivity (IC50=41.9nM, fold selectivity JAK1/2 10.6 and JAK3/2 58.1). Compound 54 also exhibited an equivalent inhibition of wild type JAK2 and the V617F mutant. Moreover, 54 inhibited the proliferation of HEL 92.1.7 cells, which carry JAK2 V617F, and gefitinib-resistant HCC827 cells. Compound 54 also suppressed STAT3 phosphorylation at Y705.


Assuntos
Descoberta de Drogas , Janus Quinase 1/antagonistas & inibidores , Janus Quinase 2/antagonistas & inibidores , Janus Quinase 3/antagonistas & inibidores , Inibidores de Proteínas Quinases/farmacologia , Pirimidinas/farmacologia , Pirróis/farmacologia , Triazóis/farmacologia , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga , Humanos , Janus Quinase 1/metabolismo , Janus Quinase 2/metabolismo , Janus Quinase 3/metabolismo , Estrutura Molecular , Inibidores de Proteínas Quinases/síntese química , Inibidores de Proteínas Quinases/química , Pirimidinas/química , Pirróis/química , Estereoisomerismo , Relação Estrutura-Atividade , Triazóis/química
3.
Bioorg Med Chem ; 23(7): 1453-62, 2015 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-25753328

RESUMO

Pheophorbide-a, a non-selective photosensitizer, was conjugated with cancer-targeting moieties, such as folic acid, the CRGDLASLC peptide, the cRGDfK peptide and leuprorelin, for the purpose of targeted photodynamic cancer therapy. The cellular uptake of pheophorbide-a conjugates in cancer cells overexpressing the corresponding receptors of the targeting moieties was largely enhanced compared with that in the receptor-negative cells. In the study of in vitro photodynamic activity and selectivity of pheophorbide-a conjugates in the receptor-positive and receptor-negative cells, a pheophorbide-a conjugate, (14) with an αvß6 ligand (CRGDLASLC) exhibited the highest selectivity in the positive FaDu cells. Targeted PDT with 14 induced cell death through apoptosis and morphological apoptosis-like characteristics. These results suggest that pheophorbide-a conjugate 14 could be utilized in selective photodynamic therapy for oral cancers primarily expressing the αvß6 receptor.


Assuntos
Clorofila/análogos & derivados , Sistemas de Liberação de Medicamentos/métodos , Fotoquimioterapia/métodos , Fármacos Fotossensibilizantes/química , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Clorofila/administração & dosagem , Clorofila/química , Relação Dose-Resposta a Droga , Humanos , Fármacos Fotossensibilizantes/administração & dosagem
4.
Bioorg Chem ; 61: 58-65, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-26123174

RESUMO

The pyridine core skeleton of the previously reported dichloropyridine-based potent hP2X7 receptor antagonist 5 (IC50 = 13 nM in hP2X7-expressing HEK293 cells) was modified with various heterocyclic scaffolds. Among the derivatives with quinoline, quinazoline, acridine, and purine scaffolds, the chloropurine-based analog 9o exhibited the most potent antagonistic activity, with an IC50 value of 176 ± 37 nM in an ethidium bromide uptake assay. In addition, 9o significantly inhibited IL-1ß release in THP-1 cells stimulated with LPS/IFN-γ/BzATP (IC50 = 120 ± 15 nM). Although 9o was less active than the previous antagonist 5, 9o exhibited greatly improved metabolic stability in the in vitro evaluation (71.4% in human, 72.3% in mouse).


Assuntos
Compostos Heterocíclicos/química , Antagonistas do Receptor Purinérgico P2X/química , Purinas/química , Animais , Avaliação Pré-Clínica de Medicamentos , Células HEK293 , Compostos Heterocíclicos/síntese química , Humanos , Camundongos , Microssomos Hepáticos/metabolismo , Ligação Proteica , Antagonistas do Receptor Purinérgico P2X/metabolismo , Receptores Purinérgicos P2X7/química , Receptores Purinérgicos P2X7/metabolismo , Relação Estrutura-Atividade
5.
Lasers Med Sci ; 30(2): 499-507, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23700080

RESUMO

Photodynamic therapy (PDT) with photosensitizer is one of the promising modalities for cancer treatment. For clinical use of PDT, screening process should be preceded to enhance sensitivity to PDT. Thus, we investigated a molecular biomarker to determine the sensitivity to pheophorbide a (Pa)-PDT in immortalized human oral keratinocytes (IHOK) and oral squamous cell carcinoma (OSCC) cell lines. Two IHOK and several OSCC cell lines were used. After Pa-PDT, cell viability was reduced by more than 50%, and reactive oxygen species were generated in IHOK and OSCC cell lines. Additionally, apoptosis occurred in PDT-treated cells. IHOK(S) and IHOK(P), the two IHOK cell lines derived from the same source, showed a difference in cytotoxicity after Pa-PDT. To explain this difference in cytotoxicity, we looked at the expression of Wnt signaling-related genes in these two cell lines, for the morphology of IHOK(S) which was spindle like and elongated and distinct from IHOK(P) and the parent cell. Among the relevant genes, runt-related transcription factor 3 (RUNX3), an apoptosis-related gene, was selected as a potential marker that confers sensitivity to PDT. We found that the cytotoxicity by Pa-PDT was proportional to RUNX3 expression in OSCC cell lines. Additionally, knockdown of RUNX3 expression reduced cytotoxicity by Pa-PDT, suggesting that RUNX3 might be a biomarker to determine sensitivity to Pa-PDT. This was the first study to find a new target molecule that enhances Pa-PDT effects in IHOK and OSCC cell lines. Hence, the development of a PDT-dependent biomarker could provide a novel approach to improve the effects of PDT on oral precancerous and cancerous lesions.


Assuntos
Carcinoma de Células Escamosas/terapia , Clorofila/análogos & derivados , Subunidade alfa 3 de Fator de Ligação ao Core/fisiologia , Neoplasias Bucais/terapia , Fotoquimioterapia/métodos , Apoptose/efeitos dos fármacos , Carcinoma de Células Escamosas/metabolismo , Linhagem Celular Tumoral , Clorofila/química , Regulação Neoplásica da Expressão Gênica , Humanos , Queratinócitos/metabolismo , Neoplasias Bucais/metabolismo , Fármacos Fotossensibilizantes/uso terapêutico , Espécies Reativas de Oxigênio/metabolismo , Transdução de Sinais , Proteínas Wnt/metabolismo
6.
Hepatology ; 53(4): 1342-51, 2011 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-21480338

RESUMO

UNLABELLED: Activation of innate immunity (natural killer [NK] cell/interferon-γ [IFN-γ]) has been shown to play an important role in antiviral and antitumor defenses as well as antifibrogenesis. However, little is known about the regulation of innate immunity during chronic liver injury. Here, we compared the functions of NK cells in early and advanced liver fibrosis induced by a 2-week or a 10-week carbon tetrachloride (CCl(4) ) challenge, respectively. Injection of polyinosinic-polycytidylic acid (poly I:C) or IFN-γ induced NK cell activation and NK cell killing of hepatic stellate cells (HSCs) in the 2-week CCl(4) model. Such activation was diminished in the 10-week CCl(4) model. Consistent with these findings, the inhibitory effect of poly I:C and IFN-γ on liver fibrosis was markedly reduced in the 10-week versus the 2-week CCl(4) model. In vitro coculture experiments demonstrated that 4-day cultured (early activated) HSCs induce NK cell activation via an NK group 2 member D/retinoic acid-induced early gene 1-dependent mechanism. Such activation was reduced when cocultured with 8-day cultured (intermediately activated) HSCs due to the production of transforming growth factor-ß (TGF-ß) by HSCs. Moreover, early activated HSCs were sensitive, whereas intermediately activated HSCs were resistant to IFN-γ-mediated inhibition of cell proliferation, likely due to elevated expression of suppressor of cytokine signaling 1 (SOCS1). Disruption of the SOCS1 gene restored the IFN-γ inhibition of cell proliferation in intermediately activated HSCs. Production of retinol metabolites by HSCs contributed to SOCS1 induction and subsequently inhibited IFN-γ signaling and functioning, whereas production of TGF-ß by HSCs inhibited NK cell function and cytotoxicity against HSCs. CONCLUSION: The antifibrogenic effects of NK cell/IFN-γ are suppressed during advanced liver injury, which is likely due to increased production of TGF-ß and expression of SOCS1 in intermediately activated HSCs.


Assuntos
Células Estreladas do Fígado/imunologia , Imunidade Inata/imunologia , Interferon gama/antagonistas & inibidores , Células Matadoras Naturais/imunologia , Cirrose Hepática/imunologia , Animais , Intoxicação por Tetracloreto de Carbono/imunologia , Células Estreladas do Fígado/efeitos dos fármacos , Interferon gama/farmacologia , Camundongos , Poli I-C/farmacologia , Proteína 1 Supressora da Sinalização de Citocina , Proteínas Supressoras da Sinalização de Citocina/biossíntese , Fator de Crescimento Transformador beta/metabolismo , Vitamina A/metabolismo
7.
Bioorg Med Chem Lett ; 21(19): 5726-9, 2011 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-21873054

RESUMO

Compounds having α,ß-unsaturated lactones display a variety of biological activities. Many research groups have tested both natural and unnatural α,ß-unsaturated lactones for as-yet undiscovered biological properties. We synthesized α,ß-unsaturated lactones with various substituents at the δ-position and studied their immunosuppressive effects, that is, the inhibition of Interleukin-2 (IL-2) production. Among the compounds synthesized, the benzofuran-substituted α,ß-unsaturated lactone 4h showed the best inhibitory activity toward IL-2 production in Jurkat e6-1 T lymphocytes (IC(50)=66.9 nM) without cytotoxicity at 10 µM. The results indicated that 4h may be useful as a potent immunosuppressive agent, as well as in IL-2-related studies.


Assuntos
Imunossupressores/síntese química , Lactonas/síntese química , Testes Imunológicos de Citotoxicidade , Avaliação Pré-Clínica de Medicamentos , Humanos , Imunossupressores/metabolismo , Imunossupressores/farmacologia , Inflamação/tratamento farmacológico , Concentração Inibidora 50 , Interleucina-2/biossíntese , Células Jurkat , Lactonas/metabolismo , Lactonas/farmacologia , Estrutura Molecular , Relação Estrutura-Atividade , Linfócitos T/metabolismo
8.
Bioorg Med Chem ; 19(18): 5383-91, 2011 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-21873067

RESUMO

Pheophorbide-a, a chlorine based photosensitizer known to be selectively accumulated in cancer cells, was conjugated with anticancer drugs, doxorubicin and paclitaxel in the purpose of selective cancer diagnosis and therapy. Pheophorbide-a was conjugated with anticancer drugs via directly and by the use of selective cleavage linkers in cancer cell. The fluorescence of pheophorbide-a and doxorubicin conjugate by excitation at 420 or 440 nm was greatly diminished possibly by the energy transfer mechanism between two fluorescent groups. However, upon treatment in cancer cells, the conjugate showed to be cleaved to restore each fluorescence of pheophorbide-a and doxorubicin after 48 h of incubation. Also, pheophorbide-a conjugates either with doxorubicin and paclitaxel inhibited the growth of various cancer cells more potently than pheophorbide-a, which displayed very weak inhibitory activity. The results indicated that the pheophorbide-a conjugates with anticancer drugs could be utilized for selective cancer therapy as well as for the fluorescence detection of cancer.


Assuntos
Antineoplásicos/farmacologia , Clorofila/análogos & derivados , Doxorrubicina/farmacologia , Corantes Fluorescentes , Neoplasias/tratamento farmacológico , Paclitaxel/farmacologia , Animais , Antineoplásicos/química , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Clorofila/química , Relação Dose-Resposta a Droga , Doxorrubicina/química , Ensaios de Seleção de Medicamentos Antitumorais , Fluorescência , Corantes Fluorescentes/química , Células HeLa , Humanos , Camundongos , Camundongos Endogâmicos C3H , Microscopia Confocal , Conformação Molecular , Neoplasias/diagnóstico , Paclitaxel/química , Espectrometria de Fluorescência , Estereoisomerismo , Relação Estrutura-Atividade , Distribuição Tecidual , Células Tumorais Cultivadas
9.
Sci Rep ; 10(1): 7527, 2020 05 05.
Artigo em Inglês | MEDLINE | ID: mdl-32371928

RESUMO

Programmed, reshaping hydrogel architectures were fabricated from sugar/hydrogel inks via a three-dimensional printing method involving a stimuli-responsive polymer. We developed a new hydrogel ink composed of monomers (acrylamide [AAm]) and N-isopropylacrylamide [NIPAAm]), and sugar (mixture of glucose and sucrose) as a pore-generator, enabling to improve printability by increasing the ink's viscoelastic properties and induce the formation of macropores in the hydrogel architectures. This study demonstrated that creating macropores in such architectures enables rapid responses to stimuli that can facilitate four-dimensional printing. We printed bilayer structures from monomer inks to which we had added sugar, and we exposed them to processes that cross-linked the monomers and leached out the sugar to create macropores. In comparison with a conventional poly(N-isopropylacrylamide) hydrogel, the macroporous hydrogels prepared using polymerization in the presence of a high concentration of sugar showed higher swelling ratios and exhibited much faster response rates to temperature changes. We used rheometry and scanning electron microscopy to characterize the properties of these inks and hydrogels. The results suggest that this method may provide a readily available route to the rapid design and fabrication of shape-morphing hydrogel architectures with potential application in soft robotics, hydrogel actuators, and tissue engineering.

10.
Mol Pharmacol ; 76(6): 1341-8, 2009 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19759354

RESUMO

The P2Y14 receptor was initially identified as a G protein-coupled receptor activated by UDP-glucose and other nucleotide sugars. We have developed several cell lines that stably express the human P2Y14 receptor, allowing facile examination of its coupling to native Gi family G proteins and their associated downstream signaling pathways (J Pharmacol Exp Ther 330:162-168, 2009). In the current study, we examined P2Y14 receptor-dependent inhibition of cyclic AMP accumulation in human embryonic kidney (HEK) 293, C6 glioma, and Chinese hamster ovary (CHO) cells stably expressing this receptor. Not only was the human P2Y14 receptor activated by UDP-glucose, but it also was activated by UDP. The apparent efficacies of UDP and UDP-glucose were similar, and the EC50 values (74, 33, and 29 nM) for UDP-dependent activation of the P2Y14 receptor in HEK293, CHO, and C6 glioma cells, respectively, were similar to the EC50 values (323, 132, and 72 nM) observed for UDP-glucose. UDP and UDP-glucose also stimulated extracellular signal-regulated kinase (ERK) 1/2 phosphorylation in P2Y14 receptor-expressing HEK293 cells but not in wild-type HEK293 cells. A series of analogs of UDP were potent P2Y14 receptor agonists, but the naturally occurring nucleoside diphosphates, CDP, GDP, and ADP exhibited agonist potencies over 100-fold less than that observed with UDP. Two UDP analogs were identified that selectively activate the P2Y14 receptor over the UDP-activated P2Y6 receptor, and these molecules stimulated phosphorylation of ERK1/2 in differentiated human HL-60 promyeloleukemia cells, which natively express the P2Y14 receptor but had no effect in wild-type HL-60 cells, which do not express the receptor. We conclude that UDP is an important cognate agonist of the human P2Y14 receptor.


Assuntos
Inibidores de Adenilil Ciclases , Proteínas de Ligação ao GTP/fisiologia , Agonistas do Receptor Purinérgico P2 , Difosfato de Uridina/farmacologia , 1-Metil-3-Isobutilxantina/farmacologia , Animais , Células CHO , Linhagem Celular , Colforsina/farmacologia , Cricetinae , Cricetulus , Ativação Enzimática/efeitos dos fármacos , MAP Quinases Reguladas por Sinal Extracelular/biossíntese , Células HL-60 , Humanos , Receptores Purinérgicos P2 , Transdução de Sinais/efeitos dos fármacos , Uridina Difosfato Glucose/farmacologia
11.
Bioorg Med Chem Lett ; 19(21): 6053-8, 2009 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-19800793

RESUMO

Screening of library compounds has yielded pyrazolodiazepine derivatives with P2X7 receptor antagonist activity. To explore the structure-activity relationships (SAR) of these pyrazolodiazepines as human P2X7 receptor antagonists, derivatives were synthesized by substitutions at positions R2 and R3 of the pyrazolodiazepine skeleton. Using a 2'(3')-O-(4-benzoylbenzoyl)ATP (BzATP)-induced fluorescent ethidium uptake assay, the activities of these derivatives were tested in HEK-293 cells stably expressing human P2X7 receptors. Moreover, the effect of these derivatives was assessed by measuring their effect on IL-1beta release induced by BzATP-induced activation of differentiated THP-1 cells. A 2-phenethyl pyrazolodiazepine derivative with a 1-methyl-1H-3-indolyl group at position R2 had fivefold greater activity than the derivative with a 5-isoquinolinyl at R2. Moreover, a benzyl moiety at R3 had fivefold greater activity than a bicyclic moiety. The stereochemical effect at C-6 showed a preference for the (R)-isomer. Among the series of active derivatives, compound 23b, with a phenethyl group at R1, a 3-methyl indole at R2, and a benzyl at R3, exhibited activity similar to that of the positive control, KN-62, as shown by the inhibitory effects of IL-1beta release.


Assuntos
Anti-Inflamatórios/síntese química , Antagonistas do Receptor Purinérgico P2 , Pirazóis/síntese química , Anti-Inflamatórios/química , Anti-Inflamatórios/farmacologia , Linhagem Celular , Etídio/metabolismo , Humanos , Interleucina-1beta/metabolismo , Pirazóis/química , Pirazóis/farmacologia , Receptores Purinérgicos P2/metabolismo , Receptores Purinérgicos P2X7 , Relação Estrutura-Atividade
12.
Bioorg Med Chem Lett ; 19(11): 3002-5, 2009 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-19419868

RESUMO

Ribose-based nucleoside 5'-diphosphates and triphosphates and related nucleotides were compared in their potency at the P2Y receptors with the corresponding nucleoside 5'-phosphonate derivatives. Phosphonate derivatives of UTP and ATP activated the P2Y(2) receptor but were inactive or weakly active at P2Y(4) receptor. Uridine 5'-(diphospho)phosphonate was approximately as potent at the P2Y(2) receptor as at the UDP-activated P2Y(6) receptor. These results suggest that removal of the 5'-oxygen atom from nucleotide agonist derivatives reduces but does not prevent interaction with the P2Y(2) receptor. Uridine 5'-(phospho)phosphonate as well as the 5'-methylenephosphonate equivalent of UMP were inactive at the P2Y(4) receptor and exhibited maximal effects at the P2Y(2) receptor that were 50% of that of UTP suggesting novel action of these analogues.


Assuntos
Nucleotídeos/síntese química , Agonistas do Receptor Purinérgico P2 , Difosfato de Adenosina/análogos & derivados , Difosfato de Adenosina/síntese química , Difosfato de Adenosina/química , Trifosfato de Adenosina/análogos & derivados , Trifosfato de Adenosina/síntese química , Trifosfato de Adenosina/química , Linhagem Celular Tumoral , Humanos , Nucleotídeos/química , Receptores Purinérgicos P2/metabolismo , Proteínas Recombinantes/agonistas , Proteínas Recombinantes/metabolismo , Difosfato de Uridina/análogos & derivados , Difosfato de Uridina/síntese química , Difosfato de Uridina/química , Uridina Trifosfato/análogos & derivados , Uridina Trifosfato/síntese química , Uridina Trifosfato/química
13.
Bioorg Med Chem ; 17(14): 5298-311, 2009 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-19502066

RESUMO

The P2Y(14) receptor, a nucleotide signaling protein, is activated by uridine-5'-diphosphoglucose 1 and other uracil nucleotides. We have determined that the glucose moiety of 1 is the most structurally permissive region for designing analogues of this P2Y(14) agonist. For example, the carboxylate group of uridine-5'-diphosphoglucuronic acid proved to be suitable for flexible substitution by chain extension through an amide linkage. Functionalized congeners containing terminal 2-acylaminoethylamides prepared by this strategy retained P2Y(14) activity, and molecular modeling predicted close proximity of this chain to the second extracellular loop of the receptor. In addition, replacement of glucose with other sugars did not diminish P2Y(14) potency. For example, the [5'']ribose derivative had an EC(50) of 0.24muM. Selective monofluorination of the glucose moiety indicated a role for the 2''- and 6''-hydroxyl groups of 1 in receptor recognition. The beta-glucoside was twofold less potent than the native alpha-isomer, but methylene replacement of the 1''-oxygen abolished activity. Replacement of the ribose ring system with cyclopentyl or rigid bicyclo[3.1.0]hexane groups abolished activity. Uridine-5'-diphosphoglucose also activates the P2Y(2) receptor, but the 2-thio analogue and several of the potent modified-glucose analogues were P2Y(14)-selective.


Assuntos
Agonistas do Receptor Purinérgico P2 , Receptores Purinérgicos P2/metabolismo , Relação Estrutura-Atividade , Nucleotídeos de Uracila/química , Nucleotídeos de Uracila/farmacologia , Uridina Difosfato Glucose/análogos & derivados , Animais , Células COS , Chlorocebus aethiops , Humanos , Modelos Moleculares , Estrutura Molecular , Ligação Proteica , Conformação Proteica , Receptores Purinérgicos P2/química , Fosfolipases Tipo C/metabolismo , Nucleotídeos de Uracila/síntese química
14.
Adv Drug Deliv Rev ; 144: 162-179, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-31176755

RESUMO

Patient deaths resulting from cardiovascular diseases are increasing across the globe, posing the greatest risk to patients in developed countries. Myocardial infarction, as a result of inadequate blood flow to the myocardium, results in irreversible loss of cardiomyocytes which can lead to heart failure. A sequela of myocardial infarction is scar formation that can alter the normal myocardial architecture and result in arrhythmias. Over the past decade, a myriad of tissue engineering approaches has been developed to fabricate engineered scaffolds for repairing cardiac tissue. This paper highlights the recent application of electrically conductive nanomaterials (carbon and gold-based nanomaterials, and electroactive polymers) to the development of scaffolds for cardiac tissue engineering. Moreover, this work summarizes the effects of these nanomaterials on cardiac cell behavior such as proliferation and migration, as well as cardiomyogenic differentiation in stem cells.


Assuntos
Condutividade Elétrica , Infarto do Miocárdio/terapia , Nanoestruturas/administração & dosagem , Engenharia Tecidual , Animais , Materiais Biocompatíveis , Carbono/administração & dosagem , Ouro/administração & dosagem , Humanos , Miócitos Cardíacos/efeitos dos fármacos , Polímeros/administração & dosagem
15.
Biofabrication ; 11(2): 025014, 2019 03 28.
Artigo em Inglês | MEDLINE | ID: mdl-30786263

RESUMO

Physicochemical and biological gradients are desirable features for hydrogels to enhance their relevance to biological environments for three-dimensional (3D) cell culture. Therefore, simple and efficient techniques to generate chemical, physical and biological gradients within hydrogels are highly desirable. This work demonstrates a technique to generate biomolecular and mechanical gradients in photocrosslinkable hydrogels by stacking and crosslinking prehydrogel solution in a layer by layer manner. Partial crosslinking of the hydrogel allows mixing of prehydrogel solution with the previous hydrogel layer, which makes a smooth gradient profile, rather than discrete layers. This technique enables the generation of concentration gradients of bovine serum albumin in both gelatin methacryloyl (GelMA) and poly(ethylene glycol) diacrylate hydrogels, as well as mechanical gradients across a hydrogel containing varying gel concentrations. Fluorescence microscopy, mechanical testing, and scanning electron microscopy show that the gradient profiles can be controlled by changing both the volume and concentration of each layer as well as intensity of UV exposure. GelMA hydrogel gradients with different Young's moduli were successfully used to culture human fibroblasts. The fibroblasts migrated along the gradient axis and showed different morphologies. In general, the proposed technique provides a rapid and simple approach to design and fabricate 3D hydrogel gradients for in vitro biological studies and potentially for in vivo tissue engineering applications.


Assuntos
Reagentes de Ligações Cruzadas/química , Hidrogéis/química , Luz , Fenômenos Mecânicos , Animais , Humanos , Metacrilatos/química , Camundongos , Células NIH 3T3 , Polímeros/química , Soroalbumina Bovina/metabolismo , Suínos , Raios Ultravioleta
16.
Bioorg Med Chem ; 16(12): 6319-32, 2008 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-18514530

RESUMO

The phosphate, uracil, and ribose moieties of uracil nucleotides were varied structurally for evaluation of agonist activity at the human P2Y(2), P2Y(4), and P2Y(6) receptors. The 2-thio modification, found previously to enhance P2Y(2) receptor potency, could be combined with other favorable modifications to produce novel molecules that exhibit high potencies and receptor selectivities. Phosphonomethylene bridges introduced for stability in analogues of UDP, UTP, and uracil dinucleotides markedly reduced potency. Truncation of dinucleotide agonists of the P2Y(2) receptor, in the form of Up(4)-sugars, indicated that a terminal uracil ring is not essential for moderate potency at this receptor and that specific SAR patterns are observed at this distal end of the molecule. Key compounds reported in this study include 9, alpha,beta-methylene-UDP, a P2Y(6) receptor agonist; 30, Up(4)-phenyl ester and 34, Up(4)-[1]glucose, selective P2Y(2) receptor agonists; dihalomethylene phosphonate analogues 16 and 41, selective P2Y(2) receptor agonists; 43, the 2-thio analogue of INS37217 (P(1)-(uridine-5')-P(4)-(2'-deoxycytidine-5')tetraphosphate), a potent and selective P2Y(2) receptor agonist.


Assuntos
Agonistas do Receptor Purinérgico P2 , Nucleotídeos de Uracila/química , Nucleotídeos de Uracila/farmacologia , Humanos , Receptores Purinérgicos P2 , Receptores Purinérgicos P2Y2 , Relação Estrutura-Atividade , Nucleotídeos de Uracila/síntese química
17.
Eur J Med Chem ; 151: 462-481, 2018 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-29649742

RESUMO

Screening a compound library of quinolinone derivatives identified compound 11a as a new P2X7 receptor antagonist. To optimize its activity, we assessed structure-activity relationships (SAR) at three different positions, R1, R2 and R3, of the quinolinone scaffold. SAR analysis suggested that a carboxylic acid ethyl ester group at the R1 position, an adamantyl carboxamide group at R2 and a 4-methoxy substitution at the R3 position are the best substituents for the antagonism of P2X7R activity. However, because most of the quinolinone derivatives showed low inhibitory effects in an IL-1ß ELISA assay, the core structure was further modified to a quinoline skeleton with chloride or substituted phenyl groups. The optimized antagonists with the quinoline scaffold included 2-chloro-5-adamantyl-quinoline derivative (16c) and 2-(4-hydroxymethylphenyl)-5-adamantyl-quinoline derivative (17k), with IC50 values of 4 and 3 nM, respectively. In contrast to the quinolinone derivatives, the antagonistic effects of the quinoline compounds (16c and 17k) were paralleled by their ability to inhibit the release of the pro-inflammatory cytokine, IL-1ß, from LPS/IFN-γ/BzATP-stimulated THP-1 cells (IC50 of 7 and 12 nM, respectively). In addition, potent P2X7R antagonists significantly inhibited the sphere size of TS15-88 glioblastoma cells.


Assuntos
Antineoplásicos/farmacologia , Glioblastoma/tratamento farmacológico , Antagonistas do Receptor Purinérgico P2X/farmacologia , Quinolinas/farmacologia , Quinolonas/farmacologia , Anti-Inflamatórios/síntese química , Anti-Inflamatórios/química , Anti-Inflamatórios/farmacologia , Antineoplásicos/síntese química , Antineoplásicos/química , Linhagem Celular , Linhagem Celular Tumoral , Glioblastoma/metabolismo , Humanos , Antagonistas do Receptor Purinérgico P2X/síntese química , Antagonistas do Receptor Purinérgico P2X/química , Quinolinas/síntese química , Quinolinas/química , Quinolonas/síntese química , Quinolonas/química , Receptores Purinérgicos P2X7/metabolismo , Relação Estrutura-Atividade
18.
J Med Chem ; 50(9): 2030-9, 2007 May 03.
Artigo em Inglês | MEDLINE | ID: mdl-17407275

RESUMO

UDP-glucose (UDPG) and derivatives are naturally occurring agonists of the Gi protein-coupled P2Y14 receptor, which occurs in the immune system. We synthesized and characterized pharmacologically novel analogues of UDPG modified on the nucleobase, ribose, and glucose moieties, as the basis for designing novel ligands in conjunction with modeling. The recombinant human P2Y14 receptor expressed in COS-7 cells was coupled to phospholipase C through an engineered Galpha-q/i protein. Most modifications of the uracil or ribose moieties abolished activity; this is among the least permissive P2Y receptors. However, a 2-thiouracil modification in 15 (EC50 49 +/- 2 nM) enhanced the potency of UDPG (but not UDP-glucuronic acid) by 7-fold. 4-Thio analogue 13 was equipotent to UDPG, but S-alkylation was detrimental. Compound 15 was docked in a rhodposin-based receptor homology model, which correctly predicted potent agonism of UDP-fructose, UDP-mannose, and UDP-inositol. The hexose moiety of UDPG interacts with multiple H-bonding and charged residues and provides a fertile region for agonist modification.


Assuntos
Agonistas do Receptor Purinérgico P2 , Uridina Difosfato Glucose/análogos & derivados , Uridina Difosfato Glucose/síntese química , Animais , Sítios de Ligação , Células COS , Chlorocebus aethiops , Humanos , Modelos Moleculares , Conformação Molecular , Receptores Purinérgicos P2 , Proteínas Recombinantes/agonistas , Estereoisomerismo , Relação Estrutura-Atividade , Uridina Difosfato Glucose/farmacologia
19.
J Med Chem ; 50(6): 1166-76, 2007 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-17302398

RESUMO

A rhodopsin-based homology model of the nucleotide-activated human P2Y2 receptor, including loops, termini, and phospholipids, was optimized with the Monte Carlo multiple minimum conformational search routine. Docked uridine 5'-triphosphate (UTP) formed a nucleobase pi-pi complex with conserved Phe3.32. Selectivity-enhancing 2'-amino-2'-deoxy substitution interacted through pi-hydrogen-bonding with aromatic Phe6.51 and Tyr3.33. A "sequential ligand composition" approach for docking the flexible dinucleotide agonist Up4U demonstrated a shift of conserved cationic Arg3.29 from the UTP gamma position to the delta position of Up4U and Up4 ribose. Synthesized nucleotides were tested as agonists at human P2Y receptors expressed in 1321N1 astrocytoma cells. 2'-Amino and 2-thio modifications were synergized to enhance potency and selectivity; compound 8 (EC50 = 8 nM) was 300-fold P2Y2-selective versus P2Y4. 2'-Amine acetylation reduced potency, and trifluoroacetylation produced intermediate potency. 5-Amino nucleobase substitution did not enhance P2Y2 potency through a predicted hydrophilic interaction possibly because of destabilization of the receptor-favored Northern conformation of ribose. This detailed view of P2Y2 receptor recognition suggests mutations for model validation.


Assuntos
Modelos Moleculares , Agonistas do Receptor Purinérgico P2 , Receptores Purinérgicos P2/química , Uridina Trifosfato/análogos & derivados , Trifosfato de Adenosina/química , Sítios de Ligação , Linhagem Celular Tumoral , Desenho de Fármacos , Humanos , Método de Monte Carlo , Conformação Proteica , Relação Quantitativa Estrutura-Atividade , Receptores Purinérgicos P2Y2 , Uridina Trifosfato/síntese química , Uridina Trifosfato/química , Uridina Trifosfato/farmacologia
20.
Adv Mater ; 29(31)2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28627043

RESUMO

Millimeter-long conducting fibers can be fabricated from carbon nanomaterials via a simple method involving the release of a prestrained protein layer. This study shows how a self-rolling process initiated by polymerization of a micropatterned layer of fibronectin (FN) results in the production of carbon nanomaterial-based microtubular fibers. The process begins with deposition of carbon nanotube (CNT) or graphene oxide (GO) particles on the FN layer. Before polymerization, particles are discrete and nonconducting, but after polymerization the carbon materials become entangled to form an interconnected conducting network clad by FN. Selective removal of FN using high-temperature combustion yields freestanding CNT or reduced GO microtubular fibers. The properties of these fibers are characterized using atomic force microscopy and Raman spectroscopy. The data suggest that this method may provide a ready route to rapid design and fabrication of aligned biohybrid nanomaterials potentially useful for future electronic applications.


Assuntos
Nanoestruturas , Grafite , Microscopia de Força Atômica , Nanotubos de Carbono , Óxidos
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