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1.
Oncoimmunology ; 13(1): 2300882, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38192443

RESUMO

Myeloid cells are known to play a crucial role in creating a tumor-promoting and immune suppressive microenvironment. Our previous study demonstrated that primary human monocytes can be polarized into immunosuppressive myeloid-derived suppressor cells (MDSCs) by cancer-associated fibroblasts (CAFs) in a 3D co-culture system. However, the molecular mechanisms underlying the immunosuppressive function of MDSCs, especially CAF-induced MDSCs, remain poorly understood. Using mass spectrometry-based proteomics, we compared cell surface protein changes among monocytes, in vitro differentiated CAF-induced MDSCs, M1/M2 macrophages, and dendritic cells, and identified an extracellular vesicle (EV)-mediated secretory phenotype of MDSCs. Functional assays using an MDSC/T-cell co-culture system revealed that blocking EV generation in CAF-induced MDSCs reversed their ability to suppress T-cell proliferation, while EVs isolated from CAF-induced MDSCs directly inhibited T-cell function. Furthermore, we identified fructose bisphosphatase 1 (FBP1) as a cargo protein that is highly enriched in EVs isolated from CAF-induced MDSCs, and pharmacological inhibition of FBP1 partially reversed the suppressive phenotype of MDSCs. Our findings provide valuable insights into the cell surface proteome of different monocyte-derived myeloid subsets and uncover a novel mechanism underlying the interplay between CAFs and myeloid cells in shaping a tumor-permissive microenvironment.


Assuntos
Fibroblastos Associados a Câncer , Vesículas Extracelulares , Células Supressoras Mieloides , Neoplasias , Humanos , Linfócitos T , Microambiente Tumoral
2.
Anticancer Drugs ; 33(2): 167-177, 2022 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-34657099

RESUMO

Hepatocellular carcinoma (HCC) is a major world public problem in the world, with high morbidity and mortality rates. Circular RNA (circRNA) circ_0073181 has been reported to be related to HCC development. However, the mechanism of circ_0073181 in HCC is far from being addressed. Circ_0073181, microRNA-548p (miR-548p) and protein tyrosine phosphatase receptor type E (PTPRE) level were detected by real-time quantitative PCR (RT-qPCR). Cell proliferation, migration, invasion and apoptosis were detected by Cell Counting Kit-8 (CCK-8), 5-ethynyl-2'-deoxyuridine, wound healing, transwell and flow cytometry assay. Protein levels of proliferating cell nuclear antigen, Bcl-2 related X protein (Bax) and PTPRE were examined by western blot assay. The binding relationship between miR-548p and circ_0073181 or PTPRE was predicted by circular RNA interactome and targetScan and then verified by a dual-luciferase reporter and RNA immunoprecipitation (RIP) assays. The biologic role of circ_0073181 on HCC tumor growth was examined by the xenograft tumor model in vivo. Circ_0073181 and PTPRE were upregulated, and miR-548p was decreased in HCC tissues and cells. Furthermore, circ_0073181 knockdown could boost proliferation, migration, invasion and repress apoptosis of HCC cells in vitro. The mechanical analysis suggested that circ_0073181 could regulate PTPRE expression by sponging miR-548p. In addition, circ_0073181 knockdown suppressed cell growth of HCC in vivo. Circ_0073181 silencing could inhibit HCC cell growth and metastasis partly by regulating the miR-548p/ PTPRE axis, providing a promising therapeutic target for the HCC treatment.


Assuntos
Carcinoma Hepatocelular/patologia , Neoplasias Hepáticas/patologia , MicroRNAs/metabolismo , RNA Circular/metabolismo , Proteínas Tirosina Fosfatases Classe 4 Semelhantes a Receptores/metabolismo , Animais , Apoptose/fisiologia , Carcinogênese/patologia , Linhagem Celular Tumoral , Movimento Celular/fisiologia , Proliferação de Células/fisiologia , Humanos , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Ensaios Antitumorais Modelo de Xenoenxerto
3.
Materials (Basel) ; 13(14)2020 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-32708753

RESUMO

Cu-Ni-Si alloys are widely used in lead frames and vacuum devices due to their high electrical conductivity and strength. In this paper, a Cu-Ni-Co-Si-Cr-(Ce) alloy was prepared by vacuum induction melting. Hot compression tests of the Cu-Ni-Co-Si-Cr and Cu-Ni-Co-Si-Cr-Ce alloys were carried out using a Gleeble-1500 simulator at 500-900 °C deformation temperatures and 0.001-10 s-1 strain rates. The texture change was analyzed by electron backscatter diffraction. The <110> fiber component dominated the texture after compression, and the texture intensity was reduced during recrystallization. Moreover, the average misorientation angle φ for Cu-Ni-Co-Si-Cr-Ce (11°) was lower than that of Cu-Ni-Co-Si-Cr (16°) under the same conditions. Processing maps were developed to determine the optimal processing window. The microstructure and precipitates of the Cu-Ni-Co-Si-Cr and Cu-Ni-Co-Si-Cr-Ce alloys were also analyzed. The average grain size of the Cu-Ni-Co-Si-Cr-Ce alloy (48 µm) was finer than that of the Cu-Ni-Co-Si-Cr alloy (80 µm). The average size of precipitates in the Cu-Ni-Co-Si-Cr alloy was 73 nm, while that of the Cu-Ni-Co-Si-Cr-Ce alloy was 27 nm. The addition of Ce delayed the occurrence of dynamic recrystallization.

4.
Cancer Immunol Res ; 8(4): 436-450, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-32075803

RESUMO

Cancer-associated fibroblasts (CAF) represent a functionally heterogeneous population of activated fibroblasts that constitutes a major component of tumor stroma. Although CAFs have been shown to promote tumor growth and mediate resistance to chemotherapy, the mechanisms by which they may contribute to immune suppression within the tumor microenvironment (TME) in lung squamous cell carcinoma (LSCC) remain largely unexplored. Here, we identified a positive correlation between CAF and monocytic myeloid cell abundances in 501 primary LSCCs by mining The Cancer Genome Atlas data sets. We further validated this finding in an independent cohort using imaging mass cytometry and found a significant spatial interaction between CAFs and monocytic myeloid cells in the TME. To delineate the interplay between CAFs and monocytic myeloid cells, we used chemotaxis assays to show that LSCC patient-derived CAFs promoted recruitment of CCR2+ monocytes via CCL2, which could be reversed by CCR2 inhibition. Using a three-dimensional culture system, we found that CAFs polarized monocytes to adopt a myeloid-derived suppressor cell (MDSC) phenotype, characterized by robust suppression of autologous CD8+ T-cell proliferation and IFNγ production. We further demonstrated that inhibiting IDO1 and NADPH oxidases, NOX2 and NOX4, restored CD8+ T-cell proliferation by reducing reactive oxygen species (ROS) generation in CAF-induced MDSCs. Taken together, our study highlights a pivotal role of CAFs in regulating monocyte recruitment and differentiation and demonstrated that CCR2 inhibition and ROS scavenging abrogate the CAF-MDSC axis, illuminating a potential therapeutic path to reversing the CAF-mediated immunosuppressive microenvironment.


Assuntos
Fibroblastos Associados a Câncer/imunologia , Carcinoma de Células Escamosas/imunologia , Neoplasias Pulmonares/imunologia , Monócitos/imunologia , Células Supressoras Mieloides/imunologia , Espécies Reativas de Oxigênio/metabolismo , Idoso , Idoso de 80 Anos ou mais , Linfócitos T CD8-Positivos/imunologia , Fibroblastos Associados a Câncer/metabolismo , Fibroblastos Associados a Câncer/patologia , Carcinoma de Células Escamosas/metabolismo , Carcinoma de Células Escamosas/patologia , Proliferação de Células , Células Cultivadas , Feminino , Humanos , Terapia de Imunossupressão , Indolamina-Pirrol 2,3,-Dioxigenase/imunologia , Indolamina-Pirrol 2,3,-Dioxigenase/metabolismo , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/patologia , Masculino , Pessoa de Meia-Idade , NADPH Oxidase 2/imunologia , NADPH Oxidase 2/metabolismo , NADPH Oxidase 4/imunologia , NADPH Oxidase 4/metabolismo , Receptores CCR2/imunologia , Receptores CCR2/metabolismo , Transdução de Sinais , Microambiente Tumoral
5.
IEEE Trans Neural Netw Learn Syst ; 31(12): 5285-5299, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-32078563

RESUMO

Recently, applications of complex-valued neural networks (CVNNs) to real-valued classification problems have attracted significant attention. However, most existing CVNNs are black-box models with poor explanation performance. This study extends the real-valued group method of data handling (RGMDH)-type neural network to the complex field and constructs a circular complex-valued group method of data handling (C-CGMDH)-type neural network, which is a white-box model. First, a complex least squares method is proposed for parameter estimation. Second, a new complex-valued symmetric regularity criterion is constructed with a logarithmic function to represent explicitly the magnitude and phase of the actual and predicted complex output to evaluate and select the middle candidate models. Furthermore, the property of this new complex-valued external criterion is proven to be similar to that of the real external criterion. Before training this model, a circular transformation is used to transform the real-valued input features to the complex field. Twenty-five real-valued classification data sets from the UCI Machine Learning Repository are used to conduct the experiments. The results show that both RGMDH and C-CGMDH models can select the most important features from the complete feature space through a self-organizing modeling process. Compared with RGMDH, the C-CGMDH model converges faster and selects fewer features. Furthermore, its classification performance is statistically significantly better than the benchmark complex-valued and real-valued models. Regarding time complexity, the C-CGMDH model is comparable with other models in dealing with the data sets that have few features. Finally, we demonstrate that the GMDH-type neural network can be interpretable.


Assuntos
Classificação , Interpretação Estatística de Dados , Redes Neurais de Computação , Algoritmos , Animais , Benchmarking , Bases de Dados Factuais , Humanos , Aprendizado de Máquina , Modelos Teóricos
6.
J Colloid Interface Sci ; 557: 266-275, 2019 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-31521975

RESUMO

The direct absorption solar collector (DASCs) with nanofluids can remarkably improve the utilization efficiency of solar energy. However, in the actual applications, the temperature distribution of the receiver is extremely uneven when the concentration of nanofluids is high or the receiver is deep. This makes the temperature of upper layer much higher than that of the lower layer, resulting in much heat loss to the surrounding by convection. Here, we propose a magnetic forced convection nanofluids absorption system, where an external rotating magnetic field is used to change the heat transfer mechanism of working fluids from traditional heat conduction to the thermal convection. It is found that the photothermal conversion efficiency of FeNi/C-EG nanofluids is up to 58.1% in this system, which is 22.7% higher than non-external rotating magnetic field when the nanofluids concentration is 50 ppm. Furthermore, the agglomeration of nanofluids can be effectively reduced by an external rotating magnetic field.

7.
RSC Adv ; 9(58): 33625-33632, 2019 Oct 18.
Artigo em Inglês | MEDLINE | ID: mdl-35528889

RESUMO

Although HfB12 is a promising surperhard material because of the boron cuboctahedron cage, the Vickers hardness of HfB12 remains controversial. We apply first-principles calculations to investigate the influence of a transition metal on the structural stability, Vickers hardness and thermodynamic properties of HfB12. The Vickers hardness of HfB12 is 39.3 GPa. In particular, the Vickers hardness of TM-doped HfB12, which are novel superhard materials, is larger than 40 GPa. The Vickers hardness of Re-doped HfB12 is up to 47.6 GPa. The improvement of Vickers hardness is that the introduction of an alloying element improves the localized hybridization between B and Hf, and then enhances the bond strength of the B-B covalent bond and the Hf-B bond. In addition, these alloying elements enhance the melting-point and Debye temperature of the HfB12. Therefore, we believe that alloying is an effective method to improve the Vickers hardness and thermodynamic properties of HfB12 superhard material.

8.
ACS Appl Mater Interfaces ; 9(42): 36817-36827, 2017 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-28975789

RESUMO

Although tremendous efforts have been devoted to the exploration of cost-effective, active, and stable electrochemical catalysts, only few significant breakthroughs have been achieved up to now. Therefore, exploring new catalysts and improving catalyst activity and stability are still major tasks at present. Controllable synthesis of Pt-based alloy nanocrystals with a uniform high-index surface and unique architecture has been regarded as an effective strategy to optimize their catalytic efficiency toward electrochemical reactions. Accordingly, here we present a one-pot facile solvothermal process to synthesize novel unique Cu@CuPt core-shell concave octahedron nanocrystals that exhibit both outstanding activity and long durability. By regulating temperatures during the synthesis process, we were able to control the reduction rate of Cu and Pt ions, which could subsequently lead to the sequential stacking of Cu and Pt atoms. Owing to the concave structure, the as-prepared core-shell nanoparticles hold a high-index surface of {312} and {413}. Such surfaces can provide a high density of atomic steps and terraces, which is suggested to be favorable for electrochemical catalysts. Specifically, the Cu@CuPt core-shell concave octahedron presents 8.6/13.1 times enhanced specific/mass activities toward the methanol oxidation reaction in comparison to those of a commercial Pt/C catalyst, respectively. Meanwhile, the as-prepared catalyst exhibits superior durability and antiaggregation properties under harsh electrochemical conditions. The facile method used here proposes a novel idea to the fabrication of nanocrystals with desired compositional distribution, and the as-prepared product offers exciting opportunities to be applied in direct methanol fuel cells.

9.
Br J Pharmacol ; 173(21): 3080-3087, 2016 11.
Artigo em Inglês | MEDLINE | ID: mdl-27417329

RESUMO

BACKGROUND AND PURPOSE: Asthma presents as a heterogeneous syndrome characterized by airway obstruction, inflammation and hyper-reactivity (AHR). Spleen tyrosine kinase (Syk) mediates allergen-induced mast cell degranulation, a central component of allergen-induced inflammation and AHR. However, the role of Syk in IgE-mediated constriction of human small airways remains unknown. In this study, we addressed whether selective inhibition of Syk attenuates IgE-mediated constriction and mast cell mediator release in human small airways. EXPERIMENTAL APPROACH: Human precision cut lung slices (hPCLS) ex vivo derived from non-asthmatic donors were incubated overnight with human IgE, dexamethasone, montelukast, antihistamines or a selective Syk inhibitor (SYKi). High-affinity IgE receptor (FcεRI) activation by anti-IgE cross-linking was performed, and constriction and mediator release measured. Airway constriction was normalized to that induced by maximal carbachol stimulation. Syk expression (determined by qPCR and immunoblot) was also evaluated in human primary airway smooth muscle (HASM) cells to determine whether Syk directly modulates HASM function. KEY RESULTS: While dexamethasone had little effect on FcεR-mediated contraction, montelukast or antihistamines partially attenuated the response. SYKi abolished anti-IgE-mediated contraction and suppressed the release of mast cell or basophil mediators from the IgE-treated hPCLS. In contrast, SYKi had little effect on the non-allergic contraction induced by carbachol. Syk mRNA and protein were undetectable in HASM cells. CONCLUSIONS AND IMPLICATIONS: A selective Syk inhibitor, but not corticosteroids, abolished FcεR-mediated contraction in human small airways ex vivo. The mechanism involved FcεRI receptor activation on mast cells or basophils that degranulate causing airway constriction, rather than direct actions on HASM.


Assuntos
Imunoglobulina E/imunologia , Pulmão/efeitos dos fármacos , Músculo Liso/efeitos dos fármacos , Inibidores de Proteínas Quinases/farmacologia , Proteínas Tirosina Quinases/antagonistas & inibidores , Baço/enzimologia , Células Cultivadas , Humanos , Técnicas In Vitro , Pulmão/citologia , Pulmão/enzimologia , Pulmão/imunologia , Contração Muscular/efeitos dos fármacos , Contração Muscular/imunologia , Músculo Liso/enzimologia , Músculo Liso/imunologia , Inibidores de Proteínas Quinases/química , Proteínas Tirosina Quinases/metabolismo
10.
Channels (Austin) ; 10(3): 247-51, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26645934

RESUMO

The CFTR chloride channel is tightly regulated by phosphorylation at multiple serine residues. Recently it has been proposed that its activity is also regulated by tyrosine kinases, however the tyrosine phosphorylation sites remain to be identified. In this study we examined 2 candidate tyrosine residues near the boundary between the first nucleotide binding domain and the R domain, a region which is important for channel function but devoid of PKA consensus sequences. Mutating tyrosines at positions 625 and 627 dramatically reduced responses to Src or Pyk2 without altering the activation by PKA, suggesting they may contribute to CFTR regulation.


Assuntos
Regulador de Condutância Transmembrana em Fibrose Cística/metabolismo , Proteínas Tirosina Quinases/metabolismo , Animais , Linhagem Celular , Cricetinae , Regulador de Condutância Transmembrana em Fibrose Cística/genética , Fenômenos Eletrofisiológicos , Ativação Enzimática , Mutagênese Sítio-Dirigida , Mutação
11.
FASEB J ; 29(9): 3945-53, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26062600

RESUMO

The cystic fibrosis transmembrane conductance regulator (CFTR) channel is activated by PKA phosphorylation of a regulatory domain that interacts dynamically with multiple CFTR domains and with other proteins. The large number of consensus sequences for phosphorylation by PKA has naturally focused most attention on regulation by this kinase. We report here that human CFTR is also phosphorylated by the tyrosine kinases p60c-Src (proto-oncogene tyrosine-protein kinase) and the proline-rich tyrosine kinase 2 (Pyk2), and they can also cause robust activation of quiescent CFTR channels. In excised patch-clamp experiments, CFTR activity during exposure to Src or Pyk2 reached ∼80% of that stimulated by PKA. Exposure to PKA after Src or Pyk2 caused a further increase to the level induced by PKA alone, implying a common limiting step. Channels became spontaneously active when v-Src or the catalytic domain of Pyk2 was coexpressed with CFTR and were further stimulated by the tyrosine phosphatase inhibitor dephostatin. Exogenous Src also activated 15SA-CFTR, a variant that lacks 15 potential PKA sites and has little response to PKA. PKA-independent activation by tyrosine phosphorylation has implications for the mechanism of regulation by the R domain and for the physiologic functions of CFTR.


Assuntos
Regulador de Condutância Transmembrana em Fibrose Cística/metabolismo , Animais , Proteína Tirosina Quinase CSK , Linhagem Celular , Cricetinae , Proteínas Quinases Dependentes de AMP Cíclico/genética , Proteínas Quinases Dependentes de AMP Cíclico/metabolismo , Regulador de Condutância Transmembrana em Fibrose Cística/genética , Quinase 2 de Adesão Focal/genética , Quinase 2 de Adesão Focal/metabolismo , Humanos , Fosforilação/fisiologia , Estrutura Terciária de Proteína , Proto-Oncogene Mas , Tirosina/genética , Tirosina/metabolismo , Quinases da Família src/genética , Quinases da Família src/metabolismo
12.
Nat Commun ; 5: 4387, 2014 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-25034454

RESUMO

Injury to lung epithelial cells has a role in multiple lung diseases. We previously identified mitsugumin 53 (MG53) as a component of the cell membrane repair machinery in striated muscle cells. Here we show that MG53 also has a physiological role in the lung and may be used as a treatment in animal models of acute lung injury. Mice lacking MG53 show increased susceptibility to ischaemia-reperfusion and overventilation-induced injury to the lung when compared with wild-type mice. Extracellular application of recombinant human MG53 (rhMG53) protein protects cultured lung epithelial cells against anoxia/reoxygenation-induced injuries. Intravenous delivery or inhalation of rhMG53 reduces symptoms in rodent models of acute lung injury and emphysema. Repetitive administration of rhMG53 improves pulmonary structure associated with chronic lung injury in mice. Our data indicate a physiological function for MG53 in the lung and suggest that targeting membrane repair may be an effective means for treatment or prevention of lung diseases.


Assuntos
Lesão Pulmonar Aguda/tratamento farmacológico , Lesão Pulmonar Aguda/patologia , Proteínas de Transporte/metabolismo , Proteínas de Transporte/farmacologia , Membrana Celular/efeitos dos fármacos , Terapia de Alvo Molecular/métodos , Lesão Pulmonar Aguda/genética , Animais , Proteínas de Transporte/administração & dosagem , Proteínas de Transporte/genética , Hipóxia Celular/efeitos dos fármacos , Membrana Celular/metabolismo , Células Cultivadas , Modelos Animais de Doenças , Células Epiteliais/efeitos dos fármacos , Células Epiteliais/patologia , Feminino , Humanos , Pulmão/patologia , Masculino , Proteínas de Membrana , Camundongos Knockout , Ratos , Ratos Sprague-Dawley , Ratos Wistar , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Proteínas Recombinantes/farmacologia , Traumatismo por Reperfusão/tratamento farmacológico , Traumatismo por Reperfusão/patologia , Respiração Artificial/efeitos adversos , Proteínas com Motivo Tripartido
13.
J Pharmacol Exp Ther ; 349(1): 75-84, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24492651

RESUMO

Nasal congestion is one of the most troublesome symptoms of many upper airways diseases. We characterized the effect of selective α2c-adrenergic agonists in animal models of nasal congestion. In porcine mucosa tissue, compound A and compound B contracted nasal veins with only modest effects on arteries. In in vivo experiments, we examined the nasal decongestant dose-response characteristics, pharmacokinetic/pharmacodynamic relationship, duration of action, potential development of tolerance, and topical efficacy of α2c-adrenergic agonists. Acoustic rhinometry was used to determine nasal cavity dimensions following intranasal compound 48/80 (1%, 75 µl). In feline experiments, compound 48/80 decreased nasal cavity volume and minimum cross-sectional areas by 77% and 40%, respectively. Oral administration of compound A (0.1-3.0 mg/kg), compound B (0.3-5.0 mg/kg), and d-pseudoephedrine (0.3 and 1.0 mg/kg) produced dose-dependent decongestion. Unlike d-pseudoephedrine, compounds A and B did not alter systolic blood pressure. The plasma exposure of compound A to produce a robust decongestion (EC(80)) was 500 nM, which related well to the duration of action of approximately 4.0 hours. No tolerance to the decongestant effect of compound A (1.0 mg/kg p.o.) was observed. To study the topical efficacies of compounds A and B, the drugs were given topically 30 minutes after compound 48/80 (a therapeutic paradigm) where both agents reversed nasal congestion. Finally, nasal-decongestive activity was confirmed in the dog. We demonstrate that α2c-adrenergic agonists behave as nasal decongestants without cardiovascular actions in animal models of upper airway congestion.


Assuntos
Agonistas de Receptores Adrenérgicos alfa 2/farmacologia , Descongestionantes Nasais/farmacologia , Receptores Adrenérgicos alfa 2/metabolismo , Rinite Vasomotora/tratamento farmacológico , Administração Intranasal , Administração Oral , Agonistas de Receptores Adrenérgicos alfa 2/administração & dosagem , Agonistas de Receptores Adrenérgicos alfa 2/farmacocinética , Agonistas de Receptores Adrenérgicos alfa 2/uso terapêutico , Antagonistas de Receptores Adrenérgicos alfa 2/farmacologia , Animais , Gatos , Modelos Animais de Doenças , Cães , Relação Dose-Resposta a Droga , Técnicas In Vitro , Masculino , Descongestionantes Nasais/administração & dosagem , Descongestionantes Nasais/farmacocinética , Descongestionantes Nasais/uso terapêutico , Mucosa Nasal/irrigação sanguínea , Mucosa Nasal/efeitos dos fármacos , Mucosa Nasal/metabolismo , Rinite Vasomotora/metabolismo , Suínos , Vasoconstrição/efeitos dos fármacos
14.
Eur J Pharmacol ; 718(1-3): 290-8, 2013 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-24012780

RESUMO

Accumulating evidence indicates protective actions of mineralocorticoid antagonists (MR antagonists) on cardiovascular pathology, which includes blunting vascular inflammation and myocardial fibrosis. We examined the anti-inflammatory and anti-fibrotic potential of MR antagonists in rodent respiratory models. In an ovalbumin allergic and challenged Brown Norway rat model, the total cell count in nasal lavage was 29,348 ± 5451, which was blocked by spironolactone (0.3-60 mg/kg, p.o.) and eplerenone (0.3-30 mg/kg, p.o.). We also found that MR antagonists attenuated pulmonary inflammation in the Brown Norway rat. A series of experiments were conducted to determine the actions of MR blockade in acute/chronic lung injury models. (1) Ex vivo lung slice rat experiments found that eplerenone (0.01 and 10 µM) and spironolactone (10 µM) diminished lung hydroxyproline concentrations by 55 ± 5, 122 ± 9, and 83 ± 8%. (2) In in vivo studies, MR antagonists attenuated the increases in bronchioalveolar lavage (BAL) neutrophils and macrophages caused by lung bleomycin exposure. In separate studies, bleomycin (4.0 U/kg, i.t.) increased lung levels of hydroxyproline by approximately 155%, which was blocked by spironolactone (10-60 mg/kg, p.o.). In a rat Lipopolysaccharide (LPS) model, spironolactone inhibited acute increases in BAL cytokines with moderate effects on neutrophils. Finally, we found that chronic LPS exposure significantly increased end expiratory lung and decreased lung elastance in the mouse. These functional effects of chronic LPS were improved by MR antagonists. Our results demonstrate that MR antagonists have significant pharmacological actions in the respiratory system.


Assuntos
Bleomicina/efeitos adversos , Antagonistas de Receptores de Mineralocorticoides/farmacologia , Pneumonia/tratamento farmacológico , Receptores de Mineralocorticoides/metabolismo , Animais , Modelos Animais de Doenças , Elasticidade/efeitos dos fármacos , Fibrose , Hidroxiprolina/metabolismo , Hipersensibilidade/tratamento farmacológico , Hipersensibilidade/metabolismo , Hipersensibilidade/patologia , Hipersensibilidade/fisiopatologia , Lipopolissacarídeos/efeitos adversos , Pulmão/efeitos dos fármacos , Pulmão/patologia , Pulmão/fisiopatologia , Masculino , Camundongos , Antagonistas de Receptores de Mineralocorticoides/uso terapêutico , Pneumonia/metabolismo , Pneumonia/patologia , Pneumonia/fisiopatologia , Ventilação Pulmonar/efeitos dos fármacos , Ratos
15.
Am J Respir Cell Mol Biol ; 49(6): 1085-92, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23889698

RESUMO

Spleen tyrosine kinase (SYK) is a key activator of signaling pathways downstream of multiple surface receptors implicated in asthma. SYK function has been extensively studied in mast cells downstream of the high-affinity IgE receptor, FcεR1. Preclinical studies have demonstrated a role for SYK in models of allergic inflammation, but a role in airway constriction has not been demonstrated. Here, we have used a potent and selective pharmacological inhibitor of SYK to determine the role of SYK in allergen-mediated inflammation and airway constriction in preclinical models. Attenuation of allergic airway responses was evaluated in a rat passive anaphylaxis model and rat and sheep inhaled allergen challenge models, as well as an ex vivo model of allergen-mediated airway constriction in rats and cynomolgus monkeys. Pharmacological inhibition of SYK dose-dependently blocked IgE-mediated tracheal plasma extravasation in rats. In a rat ovalbumin-sensitized airway challenge model, oral dosing with an SYK inhibitor led to a dose-dependent reduction in lung inflammatory cells. Ex vivo analysis of allergen-induced airway constriction in ovalbumin-sensitized brown Norway rats showed a complete attenuation with treatment of a SYK inhibitor, as well as a complete block of allergen-induced serotonin release. Similarly, allergen-mediated airway constriction was attenuated in ex vivo studies from nonhuman primate lungs. Intravenous administration of an SYK inhibitor attenuated both early- and late-phase allergen-induced increases in airway resistance in an Ascaris-sensitive sheep allergen challenge model. These data support a key role for SYK signaling in mediating allergic airway responses.


Assuntos
Alérgenos/administração & dosagem , Asma/prevenção & controle , Peptídeos e Proteínas de Sinalização Intracelular/antagonistas & inibidores , Inibidores de Proteínas Quinases/farmacologia , Proteínas Tirosina Quinases/antagonistas & inibidores , Animais , Ascaris suum/imunologia , Asma/etiologia , Asma/fisiopatologia , Broncoconstrição/efeitos dos fármacos , Broncoconstrição/imunologia , Broncoconstrição/fisiologia , Degranulação Celular/efeitos dos fármacos , Modelos Animais de Doenças , Humanos , Peptídeos e Proteínas de Sinalização Intracelular/fisiologia , Macaca fascicularis , Masculino , Mastócitos/efeitos dos fármacos , Mastócitos/imunologia , Ovalbumina/imunologia , Proteínas Tirosina Quinases/fisiologia , Ratos , Ratos Endogâmicos BN , Ratos Sprague-Dawley , Ovinos , Transdução de Sinais/efeitos dos fármacos , Quinase Syk
16.
Bioorg Med Chem Lett ; 22(9): 3291-5, 2012 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-22465636

RESUMO

The introduction of A ring pyrazole modification to the hydrocortisone C-21 heteroaryl thioethers generated compounds with excellent transrepression potency (IL-8 inhibition) compared to their hydrocortisone analogs. However, the transcriptional transactivation activity of these compounds were considerably higher than the corresponding hydrocortisone analogs. Among all the compounds evaluated, a quinoxaline thioether modification demonstrated the best overall in vitro separation.


Assuntos
Receptores de Glucocorticoides/efeitos dos fármacos , Esteroides/química , Sulfetos/química , Humanos , Hidrocortisona , Pirazóis/química , Relação Estrutura-Atividade , Sulfetos/farmacologia , Ativação Transcricional/efeitos dos fármacos
17.
Bioorg Med Chem Lett ; 22(2): 1086-90, 2012 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-22197391

RESUMO

The prednisolone C-21 heteroaryl thioethers have been synthesized and evaluated in cell based transrepression and transactivation assays. Most of the compounds demonstrated weak transactivational activity in both human and rat tyrosineaminotransferase functional assay while keeping potent anti-inflammatory activity. The benzimidazole thioether 7 exhibited comparable anti-inflammatory activity and improved safety profile compared to the classical oral steroid prednisolone.


Assuntos
Anti-Inflamatórios não Esteroides/farmacologia , Descoberta de Drogas , Receptores de Glucocorticoides/agonistas , Sulfetos/farmacologia , Administração Oral , Animais , Anti-Inflamatórios não Esteroides/administração & dosagem , Anti-Inflamatórios não Esteroides/química , Disponibilidade Biológica , Linhagem Celular , Relação Dose-Resposta a Droga , Células Hep G2 , Humanos , Conformação Molecular , Ratos , Ratos Endogâmicos BN , Receptores de Glucocorticoides/metabolismo , Estereoisomerismo , Relação Estrutura-Atividade , Sulfetos/administração & dosagem , Sulfetos/química , Tirosina Transaminase/metabolismo
18.
J Pharmacol Exp Ther ; 337(1): 256-66, 2011 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-21233198

RESUMO

We define the pharmacological and pharmacokinetic profiles of a novel α(2C)-adrenoceptor agonist, compound A [N-[3,4-dihydro-4-(1H-imidazol-4-ylmethyl)-2H-1,4-benzoxazin-6-yl]-N-ethyl-N'-methylurea]. This compound has high affinity (K(i)) for the human α(2C)-adrenoceptor (K(i) = 12 nM), and 190- to 260-fold selectivity over the α(2A)- and α(2B)-adrenoceptor subtypes. In cell-based functional assays, compound A produced good agonist (EC(50) = 166 nM) and efficacy (E(max) = 64%) responses at the α(2C)-adrenoceptor, much lower potency and efficacy at the α(2A)-adrenoceptor (EC(50) = 1525 nM; E(max) = 8%) and α(2B)-adrenoceptor (EC(50) = 5814 nM; E(max) = 21%) subtypes, and low or no affinity and functional activity at the α(1A)-, α(1B)-, and α(1D)-adrenoceptor subtypes. In the human saphenous vein postjunctional α(2C)-adrenoceptor bioassay, compound A functions as a potent agonist (pD(2) = 6.3). In a real-time contraction bioassay of pig nasal mucosa, compound A preferentially constricted the veins (EC(50) = 108 nM), and the magnitude of arteriolar contraction reached only 50% of the maximum venular responses. Compound A exhibited no effect on locomotor activity, sedation, and body temperature in mice (up to 100 mg/kg) and did not cause hypertension and mydriasis (30 mg/kg) in conscious rats. Compound A is orally bioavailable (24%) with good plasma exposure. This compound is a substrate for the efflux P-glycoprotein transporter, resulting in very low central nervous system (CNS) penetration. In summary, compound A is a highly selective, orally active, and non-CNS-penetrating α(2C)-adrenoceptor agonist with desirable in vitro and in vivo pharmacological properties suitable for the treatment of nasal congestion.


Assuntos
Agonistas Adrenérgicos/química , Agonistas Adrenérgicos/farmacologia , Compostos de Metilureia/química , Compostos de Metilureia/farmacologia , Morfolinas/química , Morfolinas/farmacologia , Atividade Motora/efeitos dos fármacos , Mucosa Nasal/efeitos dos fármacos , Receptores Adrenérgicos alfa 2/metabolismo , Veia Safena/efeitos dos fármacos , Agonistas Adrenérgicos/metabolismo , Animais , Células CHO , Cricetinae , Cricetulus , Humanos , Masculino , Compostos de Metilureia/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Morfolinas/metabolismo , Atividade Motora/fisiologia , Mucosa Nasal/metabolismo , Ratos , Ratos Sprague-Dawley , Proteínas Recombinantes/agonistas , Proteínas Recombinantes/metabolismo , Veia Safena/metabolismo , Suínos
19.
Pharmacology ; 85(5): 311-8, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20453555

RESUMO

BACKGROUND: Histamine and cysteinyl leukotrienes are pivotal mast cell mediators which contribute considerably and likely complementary to the symptoms of allergic rhinitis. Currently, we sought to explore the direct actions of histamine and leukotriene D(4) (LTD(4)), a cysteinyl leukotriene, on porcine nasal arteries and veins. We also studied combined blocks of histamine and cysteinyl leukotrienes using loratadine and montelukast in an in vivo model of allergy-mediated nasal inflammation. METHODS: For the evaluation of the action of histamine and LTD(4) on arteries and veins, porcine nasal mucosa was isolated and cut into slices (100-300 microm thick). Real-time images of the nasal arteries and veins were recorded and vessel activities estimated by changes in cross-sectional area before and after the tested drugs. For the in vivo studies, the effect of loratadine and montelukast given alone and in combination was examined on upper airway inflammation in ovalbumin-sensitized and -challenged Brown Norway rats. RESULTS: Both histamine (0.001-10 micromol/l) and LTD(4) (0.001-10 micromol/l) produced a concentration-dependent increase in the lumen area of nasal mucosa arteries and veins. Histamine (0.01 micromol/l) alone produced a 24 and 12% increase in cross-sectional areas of arteries and veins, respectively. LTD(4) (0.001 micromol/l) alone increased artery and vein dilation by about 17 and 9%, respectively. Combination treatment with histamine (0.01 micromol/l) and LTD(4) (0.001 micromol/l) increased vessel dilation by 65% (arteries) and 26% (veins). In our in vivo Brown Norway rat studies, oral loratadine (0.01-10 mg/kg) and montelukast (0.01-10 mg/kg) significantly reduced antigen-induced total nasal inflammatory cell infiltration in a dose-dependent manner. The antiinflammatory dose-response curve of loratadine was shifted to the left when studied in combination with montelukast (0.01 mg/kg). Similarly, the dose-response characteristics of montelukast (0.01-10 mg/kg) was shifted in the presence of loratadine (0.01 mg/kg). CONCLUSION: Our studies support the position that histamine and cysteinyl leukotrienes may act collaboratively to elicit allergic nasal pathologies such as upper airway inflammation and nasal vessel dilation (which may translate into increased nasal mucosal engorgement). Furthermore, the current results are supportive of the hypothesis that combined treatment of allergic rhinitis with an H(1) receptor antagonist and a CysLT(1) receptor antagonist may have greater benefit than sole treatment with these agents alone.


Assuntos
Cisteína/fisiologia , Histamina/fisiologia , Leucotrienos/fisiologia , Mucosa Nasal/irrigação sanguínea , Mucosa Nasal/efeitos dos fármacos , Rinite/tratamento farmacológico , Acetatos/farmacologia , Acetatos/uso terapêutico , Animais , Ciclopropanos , Cisteína/antagonistas & inibidores , Relação Dose-Resposta a Droga , Sinergismo Farmacológico , Quimioterapia Combinada , Feminino , Antagonistas não Sedativos dos Receptores H1 da Histamina/farmacologia , Antagonistas não Sedativos dos Receptores H1 da Histamina/uso terapêutico , Hipersensibilidade/tratamento farmacológico , Técnicas In Vitro , Antagonistas de Leucotrienos/farmacologia , Antagonistas de Leucotrienos/uso terapêutico , Leucotrieno D4/antagonistas & inibidores , Leucotrieno D4/fisiologia , Loratadina/farmacologia , Loratadina/uso terapêutico , Masculino , Mucosa Nasal/patologia , Infiltração de Neutrófilos/efeitos dos fármacos , Quinolinas/farmacologia , Quinolinas/uso terapêutico , Ratos , Ratos Endogâmicos BN , Rinite/imunologia , Sulfetos , Sus scrofa
20.
Eur J Pharmacol ; 630(1-3): 112-20, 2010 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-20006596

RESUMO

We describe the pharmacological and pharmacokinetic profiles of SCH 486757, a nociceptin/orphanin FQ peptide (NOP) receptor agonist that has recently entered human clinical trials for cough. SCH 486757 selectively binds human NOP receptor (K(i)=4.6+/-0.61nM) over classical opioid receptors. In a guinea pig capsaicin cough model, SCH 486757 (0.01-1mg/kg) suppressed cough at 2, 4, and 6h post oral administration with a maximum efficacy occurring at 4h equivalent to codeine, hydrocodone, dextromethorphan and baclofen. The antitussive effects of SCH 486757 (3.0mg/kg, p.o.) was blocked by the NOP receptor antagonist J113397 (12mg/kg, i.p.) but not by naltrexone (10mg/kg, p.o.). SCH 486757 does not produce tolerance to its antitussive activity after a 5-day BID dosing regimen. After acute and chronic dosing paradigms, SCH 486757 (1mg/kg) inhibited capsaicin-evoked coughing by 46+/-9% and 40+/-11%, respectively. In a feline mechanically-evoked cough model, SCH 486757 produces a maximum inhibition of cough and expiratory abdominal electromyogram amplitude of 59 and 61%, respectively. SCH 486757 did not significantly affect inspiratory electromyogram amplitude. We examined the abuse potential of SCH 486757 (10mg/kg, p.o.) in a rat conditioned place preference procedure which is sensitive to classical drugs of abuse, such as amphetamine and morphine. SCH 486757 was without effect in this model. Finally, SCH 486757 displays a good oral pharmacokinetic profile in the guinea pig, rat and dog. We conclude that SCH 486757 has a favorable antitussive profile in preclinical animal models.


Assuntos
Antitussígenos/uso terapêutico , Tosse/tratamento farmacológico , Receptores Opioides/agonistas , Animais , Compostos Azabicíclicos/farmacologia , Gatos , Cães , Relação Dose-Resposta a Droga , Avaliação Pré-Clínica de Medicamentos , Cobaias , Masculino , Pirimidinas/farmacologia , Ratos , Ratos Sprague-Dawley , Receptores Opioides/metabolismo , Receptor de Nociceptina
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