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2.
Biomolecules ; 11(2)2021 02 19.
Artigo em Inglês | MEDLINE | ID: mdl-33669660

RESUMO

Silver nanoparticles (AgNPs) are widely used in various fields because of their antimicrobial properties. However, many studies have reported that AgNPs can be harmful to both microorganisms and humans. Reactive oxygen species (ROS) are a key factor of cytotoxicity of AgNPs in mammalian cells and an important factor in the immune reaction of neutrophils. The immune reactions of neutrophils include the expulsion of webs of DNA surrounded by histones and granular proteins. These webs of DNA are termed neutrophil extracellular traps (NETs). NETs allow neutrophils to catch and destroy pathogens in extracellular spaces. In this study, we investigated how AgNPs stimulate neutrophils, specifically focusing on NETs. Freshly isolated human neutrophils were treated with 5 or 100 nm AgNPs. The 5 nm AgNPs induced NET formation, but the 100 nm AgNPs did not. Subsequently, we investigated the mechanism of AgNP-induced NETs using known inhibitors related to NET formation. AgNP-induced NETs were dependent on ROS, peptidyl arginine deiminase, and neutrophil elastase. The result in this study indicates that treatment of 5 nm AgNPs induce NET formation through histone citrullination by peptidyl arginine deiminase and histone cleavage by neutrophil elastase.


Assuntos
Armadilhas Extracelulares , Elastase de Leucócito/metabolismo , Nanopartículas Metálicas/química , Espécies Reativas de Oxigênio , Prata/química , Cloroquina/farmacologia , Cromatina/metabolismo , Citrulina/química , DNA/química , Ativação Enzimática , Histonas/química , Histonas/metabolismo , Humanos , Lisossomos/metabolismo , Neutrófilos/metabolismo , Reação em Cadeia da Polimerase , Transdução de Sinais , Acetato de Tetradecanoilforbol/química
3.
ACS Appl Mater Interfaces ; 12(13): 15622-15630, 2020 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-32167271

RESUMO

Noble-metal nanocrystals (NCs) are functional segments of biosensing platforms, but their sensitivity and facet effects are still challenging. Conventional synthesis using surfactants to direct crystal growth unfortunately causes adsorbate-surface hindrance, which not only reduces sensing responses but also leads to misunderstanding on facet-dependence. Herein, we utilize electrochemical CO displacement to remove residual surfactants from facet-engineered Pd NCs, and further investigate the structure-activity relationship on specific facets, for example, {100} in cubes, {111} in octahedrons, and {110} in rhombic dodecahedrons. Along with the remarkably boosted response, facet dependence is obvious for H2O2 sensing after surface cleaning. The Pd{100} shows high sensitivity, low detection limit, and wide applicable concentration range, superior to the {110} and {111}. This can be theoretically interpreted by the befitting *OH binding on {100} and thereby the facilitated H2O2 reduction kinetics. The outstanding selectivity to H2O2 ensures the high efficiency of Pd NCs to measure intracellular H2O2 and recognize different types of cancer cells. Moreover, facet effects are also evidenced in glucose detection, highlighting that this work can provide guidelines to design efficient sensing platforms.


Assuntos
Técnicas Biossensoriais/métodos , Peróxido de Hidrogênio/análise , Nanopartículas Metálicas/química , Paládio/química , Linhagem Celular Tumoral , Técnicas Eletroquímicas , Humanos , Peróxido de Hidrogênio/metabolismo , Oxirredução , Propriedades de Superfície , Acetato de Tetradecanoilforbol/química
4.
Mikrochim Acta ; 187(2): 105, 2020 01 08.
Artigo em Inglês | MEDLINE | ID: mdl-31916024

RESUMO

A nanobiocomposite was prepared from multiwalled carbon nanotubes and zein nanoparticles. It was dispersed in water/ethanol and drop cast onto a glassy carbon electrode. The modified electrode can be used for electroreduction of H2O2 (typically at a working potential of -0.71 V vs. Ag/AgCl). The electrochemical properties of the electrode were investigated by cyclic voltammetry, linear sweep voltammetry, chronoamperometry and electrochemical impedance spectroscopy. Response to H2O2 is linear in the 0.049 to 22 µM concentration range, and the detection limit is 35 nM at pH 7.0. The sensor was successfully utilized for the measurement of H2O2 in a synthetic urine sample, and for monitoring the release of H2O2 from human dermal fibroblasts and human hepatocellular carcinoma cells. Graphical abstractSchematic representation of a novel metal- and enzyme-free electrochemical nanosensor. A glassy carbon electrode was modified with a nanocomposite prepared from multiwalled carbon nanotubes and zein nanoparticles. It was applied to the identification of liver cancer cells via sensing of H2O2 and has a very low detection limit.


Assuntos
Peróxido de Hidrogênio/análise , Neoplasias Hepáticas/diagnóstico , Nanopartículas/química , Nanotubos de Carbono/química , Zeína/química , Carbono/química , Técnicas Eletroquímicas/instrumentação , Técnicas Eletroquímicas/métodos , Eletrodos , Fibroblastos , Células Hep G2 , Humanos , Peróxido de Hidrogênio/urina , Limite de Detecção , Nanocompostos/química , Reprodutibilidade dos Testes , Acetato de Tetradecanoilforbol/análogos & derivados , Acetato de Tetradecanoilforbol/química
5.
Nano Lett ; 18(9): 5899-5904, 2018 09 12.
Artigo em Inglês | MEDLINE | ID: mdl-30088769

RESUMO

Adoptive cell therapies are showing very promising results in the fight against cancer. However, these therapies are expensive and technically challenging in part due to the need of a large number of specific T cells, which must be activated and expanded in vitro. Here we describe a method to activate primary human T cells using a combination of nanostructured surfaces functionalized with the stimulating anti-CD3 antibody and the peptidic sequence arginine-glycine-aspartic acid, as well as costimulatory agents (anti-CD28 antibody and a cocktail of phorbol 12-myristate 13-acetate, ionomycin, and protein transport inhibitors). Thus, we propose a method that combines nanotechnology with cell biology procedures to efficiently produce T cells in the laboratory, challenging the current state-of-the-art expansion methodologies.


Assuntos
Materiais Revestidos Biocompatíveis/química , Ativação Linfocitária , Nanoestruturas/química , Linfócitos T/imunologia , Anticorpos Imobilizados/química , Anticorpos Imobilizados/imunologia , Antígenos CD28/imunologia , Complexo CD3/imunologia , Adesão Celular , Células Cultivadas , Ouro/química , Humanos , Imunoterapia Adotiva , Ionomicina/química , Ionomicina/imunologia , Nanoestruturas/ultraestrutura , Oligopeptídeos/química , Oligopeptídeos/imunologia , Propriedades de Superfície , Linfócitos T/citologia , Acetato de Tetradecanoilforbol/química , Acetato de Tetradecanoilforbol/imunologia , Titânio/química
6.
Int J Oncol ; 53(1): 317-328, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29750425

RESUMO

In this study, in order to investigate the effects of increased macrophage infiltration to radioresistant lung tumors in regulating natural killer (NK) cell-mediated immunity, we examined whether the treatment of radioresistant cells with conditioned medium (CM) from phorbol myristate acetate (PMA)/interleukin (IL)-4 treated THP-1 cells (used as a tumor-associated macrophage source) leads to the development of the additional resistance of tumor cells to NK cell cytotoxicity. We found that the susceptibility of THP-1 CM-treated radioresistant cells to NK cell cytotoxicity was decreased compared to the non-treated cells. In addition, it was found that such a decreased susceptibility was associated with increased programmed death receptor ligand 1 (PD-L1) and decreased natural killer group 2D (NKG2D) ligand levels in tumor cells. We further discovered that the THP-1 cells secreted a high level of IL-6, and that blocking IL-6 action by the addition of a neutralizing antibody (Ab) for IL-6 into the THP-1 CM decreased the resistance of THP-1 CM-treated radioresistant cells to NK cell cytotoxicity. Moreover, we discovered that MEK/Erk was the most critical IL-6 downstream signaling pathway in triggering the THP-1 CM effect; thus, the addition of MEK/Erk inhibitor to THP-1 CM enhanced the susceptibility of the THP-1 CM-treated radioresistant cells to NK cell cytotoxicity. On the whole, the findings of this study suggest the existence of a malignant loop characterized by increased macrophage infiltration into radioresistant cells which, in turn, promotes the development of the additional resistance of these cells to NK cell cytotoxicity.


Assuntos
Citotoxicidade Imunológica/imunologia , Células Matadoras Naturais/imunologia , Neoplasias Pulmonares/imunologia , Macrófagos/imunologia , Tolerância a Radiação/imunologia , Anticorpos Neutralizantes/imunologia , Anticorpos Neutralizantes/farmacologia , Antígeno B7-H1/imunologia , Proliferação de Células/efeitos da radiação , Meios de Cultivo Condicionados/química , Meios de Cultivo Condicionados/farmacologia , Humanos , Interleucina-6/antagonistas & inibidores , Interleucina-6/imunologia , Ligantes , Neoplasias Pulmonares/patologia , Neoplasias Pulmonares/radioterapia , Macrófagos/efeitos dos fármacos , Macrófagos/patologia , Subfamília K de Receptores Semelhantes a Lectina de Células NK/imunologia , Células-Tronco Neoplásicas/imunologia , Transdução de Sinais/efeitos dos fármacos , Acetato de Tetradecanoilforbol/química , Acetato de Tetradecanoilforbol/farmacologia
7.
Pak J Biol Sci ; 21(9): 475-479, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30724050

RESUMO

BACKGROUND AND OBJECTIVE: Zerumbone has been reported to exert anti-inflammatory, anti-ulcer and anti-hyperglycemic effects but the specific mechanism through which zerumbone exerts its anti-inflammatory action through inhibiting reactive oxygen species was not well studied. Hence, this paper studied the zerumbone capacity to inhibit intracellular and extracellular Reactive Oxygen Species (ROS) produced by whole blood cell, polymorphoneutrophil (PMNs) and macrophage cells due to the zymogen and phorbolmyristerate acetate (PMA) oxidant effect. MATERIALS AND METHODS: Zymogen and PMA based chemiluminescence assay were used to determine the immunomodulatory effect of zerumbone at concentrations (100, 10 and 1 µg mL-1) toward production of Reactive Oxygen Species (ROS) from whole blood, PMNs and macrophage. RESULTS: Zerumbone significantly inhibited intracellular and extracellular ROS production by the zymosan/PMA-activated phagocyte cells with IC50 values of (16.3±0.1, 23.7±0.1 and 4.97±0.1 µg mL-1) against whole blood, PMNs and macrophage respectively. CONCLUSION: The anti-inflammatory activity of zerumbone was so much significant that even strong oxidant (zymogen and PMA) were not able to produce reactive oxygen species when incubated together in phagocytic cells, thus suppress production of ROS. Therefore, it is highly used in herbal medicine as a potent immunomodulatory therapy in various inflammation associated diseases.


Assuntos
Imunomodulação , Neutrófilos/efeitos dos fármacos , Espécies Reativas de Oxigênio/metabolismo , Sesquiterpenos/farmacologia , Animais , Relação Dose-Resposta a Droga , Precursores Enzimáticos/química , Humanos , Sistema Imunitário , Inflamação , Concentração Inibidora 50 , Luminescência , Macrófagos/metabolismo , Camundongos , Neutrófilos/citologia , Preparações de Plantas/química , Explosão Respiratória , Acetato de Tetradecanoilforbol/química
8.
Artigo em Inglês | MEDLINE | ID: mdl-26653982

RESUMO

The response of a cell or tissue to ionizing radiation is mediated by direct damage to cellular components and indirect damage mediated by radiolysis of water. Radiation affects both irradiated cells and the surrounding cells and tissues. The radiation-induced bystander effect is defined by the presence of biological effects in cells that were not themselves in the field of irradiation. To establish the contribution of the bystander effect in the survival of the neighboring cells, lung carcinoma A549 cells were exposed to gamma-irradiation, 2Gy. The medium from the irradiated cells was transferred to non-irradiated A549 cells. Irradiated A549 cells as well as non-irradiated A549 cells cultured in the presence of medium from irradiated cells showed decrease in survival and increase in γ-H2AX and p-ATM foci, indicating a bystander effect. Bystander signaling was also observed between different cell types. Phorbol-12-myristate-13-acetate (PMA)-stimulated and gamma-irradiated U937 (human monocyte) cells induced a bystander response in non-irradiated A549 (lung carcinoma) cells as shown by decreased survival and increased γ-H2AX and p-ATM foci. Non-stimulated and/or irradiated U937 cells did not induce such effects in non-irradiated A549 cells. Since ATM protein was activated in irradiated cells as well as bystander cells, it was of interest to understand its role in bystander effect. Suppression of ATM with siRNA in A549 cells completely inhibited bystander effect in bystander A549 cells. On the other hand suppression of ATM with siRNA in PMA stimulated U937 cells caused only a partial inhibition of bystander effect in bystander A549 cells. These results indicate that apart from ATM, some additional factor may be involved in bystander effect between different cell types.


Assuntos
Adenocarcinoma/metabolismo , Proteínas Mutadas de Ataxia Telangiectasia/metabolismo , Efeito Espectador , Histonas/metabolismo , Neoplasias Pulmonares/metabolismo , Monócitos/metabolismo , Adenocarcinoma de Pulmão , Proteínas Mutadas de Ataxia Telangiectasia/genética , Linhagem Celular Tumoral , Dano ao DNA , Raios gama , Histonas/genética , Humanos , Processamento de Imagem Assistida por Computador , RNA Interferente Pequeno/genética , RNA Interferente Pequeno/metabolismo , Transdução de Sinais , Acetato de Tetradecanoilforbol/análogos & derivados , Acetato de Tetradecanoilforbol/química , Transfecção , Células U937
9.
Nanoscale ; 7(38): 16100-9, 2015 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-26372376

RESUMO

Monocytes/macrophages are important constituents of the innate immune system. Monocyte-macrophage differentiation is not only crucial for innate immune responses, but is also related to some cardiovascular diseases. Silver nanoparticles (AgNPs) are one of the most widely used nanomaterials because of their broad-spectrum antimicrobial properties. However, the effect of AgNPs on the functions of blood monocytes is scarcely reported. Here, we report the impedance effect of AgNPs on THP-1 monocyte differentiation, and that this effect was mediated by autophagy blockade and lysosomal impairment. Firstly, AgNPs inhibit phorbol 12-myristate 13-acetate (PMA)-induced monocyte differentiation by down-regulating both expression of surface marker CD11b and response to lipopolysaccharide (LPS) stimulation. Secondly, autophagy is activated during PMA-induced THP-1 monocyte differentiation, and the autophagy inhibitor chloroquine (CQ) can inhibit this process. Thirdly, AgNPs block the degradation of the autophagy substrate p62 and induce autophagosome accumulation, which demonstrates the blockade of autophagic flux. Fourthly, lysosomal impairments including alkalization and decrease of lysosomal membrane stability were observed in AgNP-treated THP-1 cells. In conclusion, we demonstrate that the impedance of monocyte-macrophage differentiation by AgNPs is mediated by autophagy blockade and lysosomal dysfunction. Our results suggest that crosstalk exists in different biological effects induced by AgNPs.


Assuntos
Autofagia/efeitos dos fármacos , Diferenciação Celular/efeitos dos fármacos , Nanopartículas Metálicas/química , Prata/química , Acetato de Tetradecanoilforbol/química , Linhagem Celular , Humanos , Macrófagos/efeitos dos fármacos , Monócitos/efeitos dos fármacos , Prata/farmacologia , Acetato de Tetradecanoilforbol/toxicidade
10.
PLoS One ; 10(8): e0134912, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26258904

RESUMO

Inflammasome complexes form upon interaction of Nod Like Receptor (NLR) proteins with pathogen associated molecular patterns (PAPMS) inside the cytosol. Stimulation of a subset of inflammasome receptors including NLRP3, NLRC4 and AIM2 triggers formation of the micrometer-sized spherical supramolecular complex called the ASC speck. The ASC speck is thought to be the platform of inflammasome activity, but the reason why a supramolecular complex is preferred against oligomeric platforms remains elusive. We observed that a set of cytosolic proteins, including the model antigen ovalbumin, tend to co-aggregate on the ASC speck. We suggest that co-aggregation of antigenic proteins on the ASC speck during intracellular infection might be instrumental in antigen presentation.


Assuntos
Apresentação de Antígeno , Proteínas Adaptadoras de Sinalização CARD/metabolismo , Proteínas de Ligação ao Cálcio/metabolismo , Proteínas de Transporte/metabolismo , Proteínas de Ligação a DNA/metabolismo , Inflamassomos/metabolismo , Antígenos/química , Caspase 1/metabolismo , Diferenciação Celular , Citoesqueleto/metabolismo , Citosol/metabolismo , Proteínas de Fluorescência Verde/metabolismo , Células HEK293 , Humanos , Inflamação , Macrófagos/metabolismo , Proteína 3 que Contém Domínio de Pirina da Família NLR , Ovalbumina/química , Complexo de Endopeptidases do Proteassoma/metabolismo , Acetato de Tetradecanoilforbol/química , Ubiquitina/metabolismo
11.
Shock ; 44(6): 524-34, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26263436

RESUMO

Vascular reactivity to vasoconstrictors and vasodilators is greatly reduced after severe trauma, shock, and sepsis or multiple organ dysfunction syndrome. This reduced vascular reactivity severely interferes with the treatment of shock and other critical conditions. In particular, it interferes with the efficacy of vasoactive agents. Consequently, it is very important to elucidate the mechanisms and search for the effective treatment measures. In recent years, a lot of studies focused on the characteristics and the change rules of vascular hyporeactivity and mechanisms following shock. Also, the treatment approaches based on various mechanisms have been a hot pot these years.


Assuntos
Vasos Sanguíneos/fisiopatologia , Choque Hemorrágico/fisiopatologia , Choque Hemorrágico/terapia , Vasoconstritores/uso terapêutico , Vasodilatadores/uso terapêutico , Acidose , Adulto , Fatores Etários , Idoso , Analgésicos Opioides/química , Vasos Sanguíneos/efeitos dos fármacos , Queimaduras/terapia , Cálcio/química , Monóxido de Carbono/química , Membrana Celular/metabolismo , Estado Terminal , Endotelinas/química , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Óxido Nítrico/química , Peptídeos/química , Proteína Quinase C/química , Fatores Sexuais , Choque Séptico/terapia , Acetato de Tetradecanoilforbol/química , Quinases Associadas a rho/metabolismo
12.
Acta Biochim Pol ; 62(3): 435-43, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26284263

RESUMO

Obtaining a suitable experimental cellular model is a major problem for neuroscience studies. Neuroblastoma cell lines have been often applied in studies related to pathological disorders of nervous system. However, in the search for an ideal model, these cells must be differentiated to cancel their tumor character. The subsequent reactions that are caused by differentiation are not always indifferent to the same model. We evaluated the effect of two well known substances, used for SH-N-SK cell line differentiation, retinoic acid (RA) and phorbol-12-myristate-13-acetate (PMA), on the induction of pro-inflammatory and pro-oxidative reactions in these cells. Cells differentiated with PMA were able to produce significantly higher amounts of pro-inflammatory cytokines whereas the release of nitric oxide radicals was similar to that in undifferentiated cells. On the contrary, in RA-differentiated cells no significant changes in cytokine production were observed and the nitric oxide release was decreased. Additionally, the RA-differentiated neuronal model was more sensible to lipopolysaccharide stimulation, producing pro-inflammatory cytokines abundantly. These results suggest that RA-differentiated SH-N-SK cells provide a more suitable experimental model for the study of molecular and cellular mechanisms of the inflammation and oxidative stress in neuronal cells.


Assuntos
Inflamação/metabolismo , Neuroblastoma/patologia , Oxigênio/química , Antineoplásicos/farmacologia , Caspase 3/metabolismo , Caspase 7/metabolismo , Diferenciação Celular , Linhagem Celular Tumoral/efeitos dos fármacos , Citocinas/metabolismo , Radicais Livres , Perfilação da Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Humanos , Inflamação/patologia , Neurônios/metabolismo , Óxido Nítrico/química , Nitritos/química , Estresse Oxidativo , Fenótipo , Acetato de Tetradecanoilforbol/química , Tretinoína/química
13.
Cancer Prev Res (Phila) ; 8(9): 817-25, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26100520

RESUMO

In this study, the effects of combining ursolic acid + resveratrol, for possible combined inhibitory effects on skin tumor promotion, were evaluated. Ursolic acid, resveratrol, and the combination of ursolic acid + resveratrol were applied topically prior to 12-O-tetracanoylphorbol-13-acetate (TPA) treatment on mouse skin to examine their effect on TPA-induced signaling pathways, epidermal hyperproliferation, skin inflammation, inflammatory gene expression, and skin tumor promotion. The combination of ursolic acid + resveratrol produced a greater inhibition of TPA-induced epidermal hyperproliferation. The combination of ursolic acid + resveratrol inhibited TPA-induced signaling pathways, including EGFR, STAT3, Src, Akt, Cox-2, Fas, NF-κB, p38 MAPK, c-Jun, and JNK1/2 while increasing levels of tumor suppressors, such as p21 and PDCD4, to a greater extent compared with the groups treated with the individual compounds. Ursolic acid + resveratrol also induced a dramatic increase of p-AMPK-α(Thr172). Combined treatment with ursolic acid + resveratrol resulted in a greater inhibition of expression of proinflammatory cytokines, including Il1a, Il1b, and Il22. Furthermore, NF-κB, Egr-1, and AP-1 DNA binding activities after TPA treatment were dramatically decreased by the combination of ursolic acid + resveratrol. Treatment with ursolic acid + resveratrol during skin tumor promotion with TPA produced greater inhibition of tumor multiplicity and tumor size than with either agent alone. Collectively, the greater ability of the combination of ursolic acid + resveratrol to inhibit skin tumor promotion was due to the greater inhibitory effects on growth factor and inflammatory signaling, skin inflammation, and epidermal hyperproliferation induced by TPA treatment.


Assuntos
Anticarcinógenos/administração & dosagem , Neoplasias Cutâneas/induzido quimicamente , Neoplasias Cutâneas/tratamento farmacológico , Estilbenos/administração & dosagem , Acetato de Tetradecanoilforbol/química , Triterpenos/administração & dosagem , Animais , Carcinogênese , Núcleo Celular/metabolismo , Proliferação de Células , Citosol/metabolismo , Feminino , Inflamação , Masculino , Camundongos , Camundongos Endogâmicos ICR , Ligação Proteica , Resveratrol , Transdução de Sinais/efeitos dos fármacos , Pele/patologia , Neoplasias Cutâneas/metabolismo , Ácido Ursólico
14.
Inflamm Res ; 63(12): 1013-21, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25374129

RESUMO

OBJECTIVES: The present study was aimed at elucidating the molecular mechanisms of anti-inflammatory activity of piceatannol (trans-3,4,3',5'-tetrahydroxystilbene) in mouse skin in vivo. METHODS: Female HR-1 hairless mice were topically treated with 12-O-tetradecanoylphorbol-13-acetate (TPA) with or without piceatannol pretreatment. Epidermal protein expression was assessed by Western blot analysis. The cyclooxygenase-2 (COX-2) expression was detected by immunohistochemistry. The DNA binding of nuclear factor-kappaB (NF-κB) and activator protein-1 (AP-1) was examined by the electrophoretic mobility gel shift assay. The catalytic activity of IκBα kinase-ß (IKKß) was measured by in vitro kinase assay. RESULTS: Pretreatment with piceatannol attenuated TPA-induced expression of COX-2 and inducible nitric oxide synthase (iNOS) in mouse skin. Piceatannol diminished nuclear translocation and the DNA binding of NF-κB through the blockade of phosphorylation and subsequent degradation of IκBα. Piceatannol attenuated the catalytic activity of IKKß and inhibited the phosphorylation of mitogen-activated protein (MAP) kinases in TPA-treated mouse skin. In addition, piceatannol decreased TPA-induced expression of c-Fos and the DNA binding of AP-1. CONCLUSION: Piceatannol inhibits TPA-induced COX-2 and iNOS expression by blocking the activation of NF-κB and AP-1 via suppression of the IKKß activity and phosphorylation of MAP kinases, which provides a mechanistic basis of its anti-inflammatory effects in mouse skin.


Assuntos
Ciclo-Oxigenase 2/metabolismo , NF-kappa B/metabolismo , Óxido Nítrico Sintase Tipo II/metabolismo , Estilbenos/farmacologia , Acetato de Tetradecanoilforbol/química , Fator de Transcrição AP-1/metabolismo , Animais , Catálise , Domínio Catalítico , Feminino , Quinase I-kappa B/metabolismo , Imuno-Histoquímica , Inflamação , Camundongos , Fosforilação , Ligação Proteica , Proteínas Proto-Oncogênicas c-fos/metabolismo , Pele/metabolismo
15.
J Am Chem Soc ; 136(38): 13209-16, 2014 Sep 24.
Artigo em Inglês | MEDLINE | ID: mdl-25207655

RESUMO

The seco-B-ring bryostatin analogue, macrodiolide WN-1, was prepared in 17 steps (longest linear sequence) and 30 total steps with three bonds formed via hydrogen-mediated C-C coupling. This synthetic route features a palladium-catalyzed alkoxycarbonylation of a C2-symmetric diol to form the C9-deoxygenated bryostatin A-ring. WN-1 binds to PKCα (Ki = 16.1 nM) and inhibits the growth of multiple leukemia cell lines. Although structural features of the WN-1 A-ring and C-ring are shared by analogues that display bryostatin-like behavior, WN-1 displays PMA-like behavior in U937 cell attachment and proliferation assays, as well as in K562 and MV-4-11 proliferation assays. Molecular modeling studies suggest the pattern of internal hydrogen bonds evident in bryostatin 1 is preserved in WN-1, and that upon docking WN-1 into the crystal structure of the C1b domain of PKCδ, the binding mode of bryostatin 1 is reproduced. The collective data emphasize the critical contribution of the B-ring to the function of the upper portion of the molecule in conferring a bryostatin-like pattern of biological activity.


Assuntos
Antineoplásicos/química , Briostatinas/química , Briozoários/química , Acetato de Tetradecanoilforbol/química , Animais , Antineoplásicos/síntese química , Antineoplásicos/farmacologia , Briostatinas/síntese química , Briostatinas/farmacologia , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Humanos , Hidrogenação , Leucemia/tratamento farmacológico , Leucemia/metabolismo , Modelos Moleculares , Proteína Quinase C-alfa/metabolismo , Acetato de Tetradecanoilforbol/síntese química , Acetato de Tetradecanoilforbol/farmacologia , Células U937
16.
Life Sci ; 113(1-2): 45-54, 2014 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-25093921

RESUMO

AIMS: Ultraviolet irradiation and carcinogens have been reported to induce epigenetic alterations, which potentially contribute to the development of skin cancer. We aimed to study the genome-wide DNA methylation profiles of skin cancers induced by ultraviolet B (UVB) irradiation and 7,12-dimethylbenz(a)anthracene (DMBA)/12-O-tetradecanoylphorbol-1,3-acetate (TPA). MAIN METHODS: Methylated DNA immunoprecipitation (MeDIP) followed by next-generation sequencing was utilized to ascertain the DNA methylation profiles in the following common mouse skin cancer models: SKH-1 mice treated with UVB irradiation and CD-1 mice treated with DMBA/TPA. Ingenuity® Pathway Analysis (IPA) software was utilized to analyze the data and to identify gene interactions among the different pathways. KEY FINDINGS: 6003 genes in the UVB group and 5424 genes in the DMBA/TPA group exhibited a greater than 2-fold change in CpG methylation as mapped by the IPA software. The top canonical pathways identified by IPA after the two treatments were ranked were pathways related to cancer development, cAMP-mediated signaling, G protein-coupled receptor signaling and PTEN signaling associated with UVB treatment, whereas protein kinase A signaling and xenobiotic metabolism signaling were associated with DMBA/TPA treatment. In addition, the mapped IL-6-related inflammatory pathways displayed alterations in the methylation profiles of inflammation-related genes linked to UVB treatment. SIGNIFICANCE: Genes with altered methylation were ranked in the UVB and DMBA/TPA models, and the molecular interaction networks of those genes were identified by the IPA software. The genome-wide DNA methylation profiles of skin cancers induced by UV irradiation or by DMBA/TPA will be useful for future studies on epigenetic gene regulation in skin carcinogenesis.


Assuntos
Metilação de DNA , Regulação Neoplásica da Expressão Gênica , Genoma , Neoplasias Cutâneas/genética , 9,10-Dimetil-1,2-benzantraceno/química , Animais , Carcinógenos/química , Ilhas de CpG , Modelos Animais de Doenças , Epigênese Genética , Feminino , Inflamação , Camundongos , Análise de Sequência de DNA , Transdução de Sinais , Neoplasias Cutâneas/induzido quimicamente , Acetato de Tetradecanoilforbol/análogos & derivados , Acetato de Tetradecanoilforbol/química , Raios Ultravioleta
17.
Mediators Inflamm ; 2014: 507272, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24891766

RESUMO

We revisited the action of a carotenoid, the lycopene, on the expression of proinflammatory genes, reactive oxygen species (ROS) production, and metalloprotease (MMP9) activity. THP1 and Caco2 cell lines were used as in vitro models for the two main cell types found in intestine tissue, that is, monocytes and epithelial cells. Proinflammatory condition was induced using either phorbol ester acetate (PMA), lipopolysaccharide (LPS) or tumor necrosis factor (TNF). In THP1 cells, short term pretreatment (2 h) with a low concentration (2 µM) of lycopene reinforce proinflammatory gene expression. The extent of the effect of lycopene is dependent on the proinflammtory stimulus (PMA, LPS or TNF) used. Lycopene enhanced MMP9 secretion via a c-AMP-dependent process, and reduced ROS production at higher concentrations than 2 µM. Cell culture media, conditioned by PMA-treated monocytes and then transferred on CaCo-2 epithelial cells, induced a proinflammatory state in these cells. The extent of this inflammatory effect was reduced when cells has been pretreated (12 h) with lycopene. At low concentration (2 µM or less), lycopene appeared to promote an inflammatory state not correlated with ROS modulation. At higher concentration (5 µM-20 µM), an anti-inflammatory effect takes place as a decrease of ROS production was detected. So, both concentration and time have to be considered in order to define the exact issue of the effect of carotenoids present in meals.


Assuntos
Antioxidantes/farmacologia , Carotenoides/farmacologia , Regulação da Expressão Gênica , Inflamação/tratamento farmacológico , Metaloproteinase 9 da Matriz/metabolismo , Transcrição Gênica , Células CACO-2 , Linhagem Celular , AMP Cíclico/metabolismo , Perfilação da Expressão Gênica , Humanos , Lipopolissacarídeos/química , Licopeno , Monócitos/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Acetato de Tetradecanoilforbol/química , Fator de Necrose Tumoral alfa/química , beta-Galactosidase/metabolismo
18.
Mediators Inflamm ; 2014: 406514, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24948847

RESUMO

Toll-like receptor (TLR) ligands are being developed for use as vaccine adjuvants and as immunomodulators because of their ability to stimulate innate and adaptive immune responses. Flagellin, a TLR5 ligand, was reported to show potent mucosal vaccine adjuvant activity. To identify ligands that potentiate the adjuvant activity of flagellin, we screened a plant library using HEK293T cells transiently cotransfected with phTLR5 and pNF- κ B-SEAP plasmids. The 90% EtOH extract from Croton tiglium showed significant NF- κ B transactivation in a TLR5-independent manner along with the increase of a flagellin activity. We have studied to characterize an active component from Croton tiglium and to elucidate the action mechanisms. Phorbol 12-myristate 13-acetate (PMA) was isolated as an active component of Croton tiglium by activity-guided fractionation, column chromatography, HPLC, NMR, and MS. PMA at a range of nM induced PKC-dependent NF- κ B activation and IL-8 production in both TLR5- and TLR5+ assay systems. In in vivo mouse vaccination model, PMA induced antigen-specific IgG and IgA antibody responses and increased IL-12 production corresponding to T cell responses in spleen lymphocytes. These results suggest that PMA would serve as an efficacious mucosal vaccine adjuvant.


Assuntos
Adjuvantes Imunológicos/química , Transdução de Sinais , Acetato de Tetradecanoilforbol/química , Receptores Toll-Like/metabolismo , Animais , Células CACO-2 , Núcleo Celular/metabolismo , Croton/química , Citosol/metabolismo , Flagelina/química , Células HEK293 , Humanos , Interleucina-8/metabolismo , Ligantes , Linfócitos/citologia , Camundongos , Camundongos Endogâmicos BALB C , NF-kappa B/metabolismo , Extratos Vegetais/química , Baço/citologia , Linfócitos T/imunologia , Receptor 5 Toll-Like/metabolismo , Ativação Transcricional , Vacinas
19.
J Biomol Screen ; 19(6): 890-9, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24464434

RESUMO

Protein kinases C (PKC) modulate the activity of the Kv11.1 ion channel current (hERG). However, the differential effects of specific PKC subtypes on the biophysics of the channel are unknown. The pharmaceutical tools to selectively modulate PKC subtypes are not membrane permeable and must be added directly to the intracellular solution in electrophysiology studies. Here, the PatchXpress electrophysiology robot was used to voltage clamp up to 16 cells simultaneously yet asynchronously across individual Sealchip chambers. The precision afforded by repeats of automation procedures minimized the experimental errors typical of these assays. Eight well-known PKC selective peptidomimmetics and general synthetic modulators were used to modulate the protein-protein interactions between hERG and the major PKC subtypes. We identified a specific role for the PKCε inhibitory peptidomimmetics in decreasing PKC-induced hERG τ activation (80%) and half-maximum activation voltage (90%) at steady state; a specific PKCε activator exhibited the opposite effect. Disruption of PKCß, PKCα, and PKCη interactions also showed significant effects albeit of lower magnitudes. The effect of PKCδ inhibitor was only marginal. A significant correlation was observed between the shifts in τ activation and half-maximum voltage at steady state (R(2)= 0.85). Peak current amplitudes and time constant of deactivation remained unaffected in all conditions.


Assuntos
Canal de Potássio ERG1/química , Proteína Quinase C/química , Acetato de Tetradecanoilforbol/química , Membrana Celular/metabolismo , Eletrofisiologia , Células HEK293 , Humanos , Cinética , Peptídeos/química , Peptidomiméticos/química , Mapeamento de Interação de Proteínas , Isoformas de Proteínas/química , Inibidores de Proteínas Quinases/química , Robótica , Transfecção
20.
J Invest Dermatol ; 134(4): 1023-1032, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24177187

RESUMO

Phytosphingosine is abundant in plants and fungi and is found in mammalian epidermis, including the stratum corneum. Phytosphingosine and its derivatives N-acetyl phytosphingosine and tetraacetyl phytosphingosine are part of the natural defense system of the body. However, these molecules exhibit strong toxicities at high concentrations. We synthesized phytosphingosine derivatives, mYG-II-6 ((Z)-4-oxo-4-(((2S,3S,4R)-1,3,4-trihydroxyoctadecan-2-yl)amino)but-2-enoic acid) and fYG-II-6 ((E)-4-oxo-4-(((2S,3S,4R)-1,3,4-trihydroxyoctadecan-2-yl)amino)but-2-enoic acid), to increase efficacy and decrease toxicity, and the biological activities of the derivatives in the inflammatory response were examined. Both YG-II-6 compounds effectively suppressed 12-O-tetradecanoylphorbol-13-acetate (TPA)-induced inflammatory skin damage and inflammatory response in a mouse model. In addition, topical application of fYG-II-6 suppressed ear swelling and psoriasiform dermatitis in the ears of IL-23-injected mice. Anti-inflammatory and antipsoriatic activities of the phytosphingosine derivatives inhibited NF-κB, JAK/signal transducer and activator of transcription (JAK/STAT), and mitogen-activated protein kinase (MAPK) signaling. Finally, the YG-II-6 compounds induced programmed cell death in keratinocytes and mouse skin and were less toxic than phytosphingosine. Our study demonstrated that the phytosphingosine-derived YG-II-6 compounds have much stronger biological potencies than the lead compounds. The YG-II-6 compounds ameliorated inflammatory skin damage. Thus, YG-II-6 compounds are potential topical agents for treating chronic inflammatory skin diseases, such as psoriasis.


Assuntos
Inflamação/tratamento farmacológico , Janus Quinase 1/metabolismo , Queratinócitos/citologia , NF-kappa B/metabolismo , Pele/metabolismo , Esfingosina/análogos & derivados , Adulto , Animais , Anti-Inflamatórios/química , Apoptose , Sobrevivência Celular , Dermatite/metabolismo , Humanos , Interleucina-23/metabolismo , Janus Quinase 1/antagonistas & inibidores , Queratinócitos/efeitos dos fármacos , Leucócitos Mononucleares/citologia , Sistema de Sinalização das MAP Quinases , Masculino , Camundongos , NF-kappa B/antagonistas & inibidores , Psoríase/metabolismo , Transdução de Sinais , Pele/efeitos dos fármacos , Pele/patologia , Esfingosina/química , Linfócitos T/citologia , Acetato de Tetradecanoilforbol/química
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