Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 15 de 15
Filtrar
Mais filtros











Base de dados
Intervalo de ano de publicação
1.
ACS Appl Bio Mater ; 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38558434

RESUMO

Most ovarian carcinoma (OvCa) patients present with advanced disease at the time of diagnosis. Malignant, metastatic OvCa is invasive and has poor prognosis, exposing the need for improved therapeutic targeting. High CD47 (OvCa) and SIRPα (macrophage) expression has been linked to decreased survival, making this interaction a significant target for therapeutic discovery. Even so, previous attempts have fallen short, limited by CD47 antibody specificity and efficacy. Macrophages are an important component of the OvCa tumor microenvironment and are manipulated to aid in cancer progression via CD47-SIRPα signaling. Thus, we have leveraged lipid-based nanoparticles (LNPs) to design a therapy uniquely situated to home to phagocytic macrophages expressing the SIRPα protein in metastatic OvCa. CD47-SIRPα presence was evaluated in patient histological sections using immunohistochemistry. 3D tumor spheroids generated on a hanging drop array with OVCAR3 high-grade serous OvCa and THP-1-derived macrophages created a representative model of cellular interactions involved in metastatic OvCa. Microfluidic techniques were employed to generate LNPs encapsulating SIRPα siRNA (siSIRPα) to affect the CD47-SIRPα signaling between the OvCa and macrophages. siSIRPα LNPs were characterized for optimal size, charge, and encapsulation efficiency. Uptake of the siSIRPα LNPs by macrophages was assessed by Incucyte. Following 48 h of 25 nM siSIRPα treatment, OvCa/macrophage heterospheroids were evaluated for SIRPα knockdown, platinum chemoresistance, and invasiveness. OvCa patient tumors and in vitro heterospheroids expressed CD47 and SIRPα. Macrophages in OvCa spheroids increased carboplatin resistance and invasion, indicating a more malignant phenotype. We observed successful LNP uptake by macrophages causing significant reduction in SIRPα gene and protein expressions and subsequent reversal of pro-tumoral alternative activation. Disrupting CD47-SIRPα interactions resulted in sensitizing OvCa/macrophage heterospheroids to platinum chemotherapy and reversal of cellular invasion outside of heterospheroids. Ultimately, our results strongly indicate the potential of using LNP-based nanoimmunotherapy to reduce malignant progression of ovarian cancer.

2.
Pharmaceuticals (Basel) ; 16(12)2023 Dec 04.
Artigo em Inglês | MEDLINE | ID: mdl-38139812

RESUMO

Anaplastic thyroid cancer (ATC) is an aggressive form of thyroid cancer (TC), accounting for 50% of total TC-related deaths. Although therapeutic approaches against TC have improved in recent years, the survival rate remains low, and severe adverse effects are commonly reported. However, unexplored alternatives based on natural compounds, such as lysicamine, an alkaloid found in plants with established cytotoxicity against breast and liver cancers, offer promise. Therefore, this study aimed to explore the antineoplastic effects of lysicamine in papillary TC (BCPAP) and ATC (HTH83 and KTC-2) cells. Lysicamine treatment reduced cell viability, motility, colony formation, and AKT activation while increasing the percentage of necrotic cells. The absence of caspase activity confirmed apoptosis-independent cell death. Necrostatin-1 (NEC-1)-mediated necrosome inhibition reduced lysicamine-induced necrosis in KTC-2, suggesting necroptosis induction via a reactive oxygen species (ROS)-independent mechanism. Additionally, in silico analysis predicted lysicamine target proteins, particularly those related to MAPK and TGF-ß signaling. Our study demonstrated lysicamine's potential as an antineoplastic compound in ATC cells with a proposed mechanism related to inhibiting AKT activation and inducing cell death.

3.
Immunology ; 169(2): 132-140, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-36465031

RESUMO

Breast cancer liver metastases (BCLM) are usually unresectable and difficult to treat with systemic chemotherapy. A major reason for chemotherapy failure is that BCLM are typically small, avascular nodules, with poor transport and fast washout of therapeutics from surrounding capillaries. We have previously shown that nanoalbumin-bound paclitaxel (nab-PTX) encapsulated in porous silicon multistage nanovectors (MSV) is preferentially taken up by tumour-associated macrophages (TAM) in the BCLM microenvironment. The TAM alter therapeutic transport characteristics and retain it in the tumour vicinity, increasing cytotoxicity. Computational modeling has shown that therapeutic regimens could be designed to eliminate single lesions. To evaluate clinically-relevant scenarios, this study develops a modeling framework to evaluate MSV-nab-PTX therapy targeting multiple BCLM. An experimental model of BCLM, splenic injection of breast cancer 4 T1 cells was established in BALB/C mice. Livers were analyzed histologically to determine size and density of BCLM. The data were used to calibrate a 3D continuum mixture model solved via distributed computing to enable simulation of multiple BCLM. Overall tumour burden was analyzed as a function of metastases number and potential therapeutic regimens. The computational model enables realistic 3D representation of metastatic tumour burden in the liver, with the capability to evaluate BCLM growth and therapy response for hundreds of lesions. With the given parameter set, the model projects that repeated MSV-nab-PTX treatment in intervals <7 days would control the tumour burden. We conclude that nanotherapy targeting TAM associated with BCLM may be evaluated and fine-tuned via 3D computational modeling that realistically simulates multiple metastases.


Assuntos
Neoplasias Hepáticas , Animais , Camundongos , Camundongos Endogâmicos BALB C , Neoplasias Hepáticas/tratamento farmacológico , Macrófagos , Paclitaxel/uso terapêutico , Microambiente Tumoral , Melanoma Maligno Cutâneo
4.
J Control Release ; 349: 796-811, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35914613

RESUMO

We describe a role of CD44-mediated signaling during host-defense against tuberculosis (TB) using a mouse model of TB and studies in M. tuberculosis (Mtb) infected human macrophage (MФ). Liposomes targeting CD44 using thioaptamers (CD44TA-LIP) were designed and tested as new vaccines to boost host immunity in TB. CD44TA-LIP enhanced killing of Mtb in human MФ, which correlated with an increased production of pro-inflammatory cytokines IL-1ß, TNF-α and IL-12. CD44TA-LIP activated MФ showed an enhanced MHC-II dependent antigen presentation to CD4 T-cells. Inhibition of cellular proliferation and cytoskeleton rearrangement pathways downstream of CD44 signaling abrogated CD44TA-LIP-induced antimicrobial effects. Blockade of inflammatory pathways also reduced antigen presentation by MФ and activation of CD4 T cells. Mtb infected MФ treated with CD44TA-LIP exhibited increased nitric oxide and HßD2 defensin peptide production. Among Mtb infected mice with increased lung and spleen loads of organisms, intranasal administration of CD44TA-LIP led to a ten-fold reduction of colony forming units of Mtb and elevated IFN-γ + CD4, effector, central and resident memory T cells. Biodistribution studies demonstrated that CD44TA-LIP preferentially accumulated in the lungs and were associated with CD11b + cells. CD44TA-LIP treated mice showed no weight loss or increased liver LDH levels. This study highlights the importance of CD44-mediated signaling in host-defense during TB and the therapeutic potential of CD44TA-LIP.


Assuntos
Anti-Infecciosos , Receptores de Hialuronatos/metabolismo , Mycobacterium tuberculosis , Nanopartículas , Tuberculose , Defensinas , Humanos , Interleucina-12 , Lipossomos , Antígeno de Macrófago 1 , Óxido Nítrico , Distribuição Tecidual , Tuberculose/tratamento farmacológico , Fator de Necrose Tumoral alfa
5.
Front Oncol ; 11: 703995, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34540670

RESUMO

This study aims to identify prognostic factors in nasopharyngeal carcinoma (NPC) to improve the current 8th edition TNM classification. A systematic review of the literature reported between 2013 and 2019 in PubMed, Embase, and Scopus was conducted. Studies were included if (1) original clinical studies, (2) ≥50 NPC patients, and (3) analyses on the association between prognostic factors and overall survival. The data elements of eligible studies were abstracted and analyzed. A level of evidence was synthesized for each suggested change to the TNM staging and prognostic factors. Of 5,595 studies screened, 108 studies (44 studies on anatomical criteria and 64 on non-anatomical factors) were selected. Proposed changes/factors with strong evidence included the upstaging paranasal sinus to T4, defining parotid lymph node as N3, upstaging N-category based on presence of lymph node necrosis, as well as the incorporation of non-TNM factors including EBV-DNA level, primary gross tumor volume (GTV), nodal GTV, neutrophil-lymphocyte ratio, lactate dehydrogenase, C-reactive protein/albumin ratio, platelet count, SUVmax of the primary tumor, and total lesion glycolysis. This systematic review provides a useful summary of suggestions and prognostic factors that potentially improve the current staging system. Further validation studies are warranted to confirm their significance.

6.
Cancer Immunol Immunother ; 69(5): 731-744, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32036448

RESUMO

Tumor-associated macrophages (TAMs) have been shown to both aid and hinder tumor growth, with patient outcomes potentially hinging on the proportion of M1, pro-inflammatory/growth-inhibiting, to M2, growth-supporting, phenotypes. Strategies to stimulate tumor regression by promoting polarization to M1 are a novel approach that harnesses the immune system to enhance therapeutic outcomes, including chemotherapy. We recently found that nanotherapy with mesoporous particles loaded with albumin-bound paclitaxel (MSV-nab-PTX) promotes macrophage polarization towards M1 in breast cancer liver metastases (BCLM). However, it remains unclear to what extent tumor regression can be maximized based on modulation of the macrophage phenotype, especially for poorly perfused tumors such as BCLM. Here, for the first time, a CRISPR system is employed to permanently modulate macrophage polarization in a controlled in vitro setting. This enables the design of 3D co-culture experiments mimicking the BCLM hypovascularized environment with various ratios of polarized macrophages. We implement a mathematical framework to evaluate nanoparticle-mediated chemotherapy in conjunction with TAM polarization. The response is predicted to be not linearly dependent on the M1:M2 ratio. To investigate this phenomenon, the response is simulated via the model for a variety of M1:M2 ratios. The modeling indicates that polarization to an all-M1 population may be less effective than a combination of both M1 and M2. Experimental results with the CRISPR system confirm this model-driven hypothesis. Altogether, this study indicates that response to nanoparticle-mediated chemotherapy targeting poorly perfused tumors may benefit from a fine-tuned M1:M2 ratio that maintains both phenotypes in the tumor microenvironment during treatment.


Assuntos
Paclitaxel Ligado a Albumina/administração & dosagem , Neoplasias da Mama/terapia , Neoplasias Hepáticas/terapia , Ativação de Macrófagos/genética , Macrófagos/imunologia , Modelos Biológicos , Animais , Neoplasias da Mama/imunologia , Neoplasias da Mama/patologia , Sistemas CRISPR-Cas/genética , Diferenciação Celular/genética , Diferenciação Celular/imunologia , Engenharia Celular , Linhagem Celular Tumoral/transplante , Técnicas de Cocultura , Modelos Animais de Doenças , Feminino , Humanos , Lipossomos , Neoplasias Hepáticas/imunologia , Neoplasias Hepáticas/secundário , Camundongos , Nanopartículas , Esferoides Celulares , Resultado do Tratamento , Microambiente Tumoral/efeitos dos fármacos , Microambiente Tumoral/genética , Microambiente Tumoral/imunologia
7.
J Oncol Pharm Pract ; 25(5): 1053-1057, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29651918

RESUMO

PURPOSE: Fosaprepitant (Emend®) is an antiemetic frequently used for the prevention of chemotherapy-induced nausea and vomiting. We previously documented an overall 28.7% incidence of infusion-site reactions in patients receiving fosaprepitant via peripheral venous access. These data resulted in a practice change within our institution; fosaprepitant is administered in more dilute concentrations over 30 min to prevent these adverse events. This retrospective study explored the impact of this practice change on the incidence of infusion-site reactions. METHODS: Medical records of patients with cancer receiving intravenous fosaprepitant through a peripheral intravenous line were reviewed. The primary objective of this study was to compare the incidence of infusion-site reactions before the practice change to the incidence after the practice change. Data collection included demographics, fosaprepitant infusion information, and grading of reactions. RESULTS: Between September 2013 and December of 2013, charts of 122 patients receiving intravenous fosaprepitant through a peripheral line at the The Arthur G. James Cancer Hospital at The Ohio State University were reviewed. We found a 5.74% incidence of infusion-site reactions which is significantly lower than the prechange incidence of 28.7% (p < 0.001). CONCLUSIONS: Infusion-site reactions were significantly reduced when fosaprepitant was diluted to 150 mg/250 ml and infused over 30 min. We recommend oncology pharmacists consider using the more dilute fosaprepitant preparation and 30 min infusion duration when administering via a peripheral intravenous line to improve patient tolerance.


Assuntos
Antieméticos/efeitos adversos , Morfolinas/efeitos adversos , Neoplasias/tratamento farmacológico , Antieméticos/uso terapêutico , Institutos de Câncer , Coleta de Dados , Feminino , Humanos , Incidência , Infusões Intravenosas , Masculino , Pessoa de Meia-Idade , Morfolinas/administração & dosagem , Náusea/induzido quimicamente , Farmacêuticos/organização & administração , Estudos Retrospectivos , Vômito/induzido quimicamente
8.
J Cell Physiol ; 232(11): 3139-3145, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28059438

RESUMO

Numerous protocols exist for isolating aortic endothelial and smooth muscle cells from small animals. However, establishing a protocol for isolating pure cell populations from large animal vessels that are more elastic has been challenging. We developed a simple sequential enzymatic approach to isolate highly purified populations of porcine aortic endothelial and smooth muscle cells. The lumen of a porcine aorta was filled with 25 U/ml dispase solution and incubated at 37°C to dissociate the endothelial cells. The smooth muscle cells were isolated by mincing the tunica media of the treated aorta and incubating the pieces in 0.2% and then 0.1% collagenase type I solution. The isolated endothelial cells stained positive for von Willebrand factor, and 97.2% of them expressed CD31. Early and late passage endothelial cells had a population doubling time of 38 hr and maintained a capacity to take up DiI-Ac-LDL and form tubes in Matrigel®. The isolated smooth muscle cells stained highly positive for alpha-smooth muscle actin, and an impurities assessment showed that only 1.8% were endothelial cells. Population doubling time for the smooth muscle cells was ∼70 hr at passages 3 and 7; and the cells positively responded to endothelin-1, as shown by a 66% increase in the intracellular calcium level. This simple protocol allows for the isolation of highly pure populations of endothelial and smooth muscle cells from porcine aorta that can survive continued passage in culture without losing functionality or becoming overgrown by fibroblasts.


Assuntos
Separação Celular/métodos , Células Endoteliais/fisiologia , Músculo Liso Vascular/citologia , Miócitos de Músculo Liso/patologia , Animais , Aorta/citologia , Transporte Biológico , Biomarcadores/sangue , Cálcio/metabolismo , Proliferação de Células , Colagenases/metabolismo , Endopeptidases/metabolismo , Células Endoteliais/efeitos dos fármacos , Células Endoteliais/metabolismo , Endotelina-1/farmacologia , Citometria de Fluxo , Lipoproteínas LDL/metabolismo , Microscopia de Fluorescência , Miócitos de Músculo Liso/efeitos dos fármacos , Miócitos de Músculo Liso/metabolismo , Neovascularização Fisiológica , Fenótipo , Sus scrofa , Fatores de Tempo
9.
PLoS One ; 11(3): e0149679, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26930653

RESUMO

Several clinical studies show that individuals with HIV are at an increased risk for worsened lung function and for the development of COPD, although the mechanism underlying this increased susceptibility is poorly understood. The airway epithelium, situated at the interface between the external environment and the lung parenchyma, acts as a physical and immunological barrier that secretes mucins and cytokines in response to noxious stimuli which can contribute to the pathobiology of chronic obstructive pulmonary disease (COPD). We sought to determine the effects of HIV on the lung epithelium. We grew primary normal human bronchial epithelial (NHBE) cells and primary lung epithelial cells isolated from bronchial brushings of patients to confluence and allowed them to differentiate at an air- liquid interface (ALI) to assess the effects of HIV on the lung epithelium. We assessed changes in monolayer permeability as well as the expression of E-cadherin and inflammatory modulators to determine the effect of HIV on the lung epithelium. We measured E-cadherin protein abundance in patients with HIV compared to normal controls. Cell associated HIV RNA and DNA were quantified and the p24 viral antigen was measured in culture supernatant. Surprisingly, X4, not R5, tropic virus decreased expression of E-cadherin and increased monolayer permeability. While there was some transcriptional regulation of E-cadherin, there was significant increase in lysosome-mediated protein degradation in cells exposed to X4 tropic HIV. Interaction with CXCR4 and viral fusion with the epithelial cell were required to induce the epithelial changes. X4 tropic virus was able to enter the airway epithelial cells but not replicate in these cells, while R5 tropic viruses did not enter the epithelial cells. Significantly, X4 tropic HIV induced the expression of intercellular adhesion molecule-1 (ICAM-1) and activated extracellular signal-regulated kinase (ERK). We demonstrate that HIV can enter airway epithelial cells and alter their function by impairing cell-cell adhesion and increasing the expression of inflammatory mediators. These observed changes may contribute local inflammation, which can lead to lung function decline and increased susceptibility to COPD in HIV patients.


Assuntos
Células Epiteliais/virologia , Epitélio/virologia , Infecções por HIV/virologia , HIV-1/fisiologia , Pneumonia/virologia , Western Blotting , Caderinas/genética , Caderinas/metabolismo , Células Cultivadas , Células Epiteliais/metabolismo , Epitélio/metabolismo , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Expressão Gênica , Infecções por HIV/genética , Infecções por HIV/metabolismo , HIV-1/classificação , HIV-1/genética , Interações Hospedeiro-Patógeno , Humanos , Molécula 1 de Adesão Intercelular/metabolismo , Pulmão/patologia , Pulmão/virologia , Microscopia Confocal , Pneumonia/genética , Pneumonia/metabolismo , Doença Pulmonar Obstrutiva Crônica/genética , Doença Pulmonar Obstrutiva Crônica/metabolismo , Doença Pulmonar Obstrutiva Crônica/virologia , Receptores CXCR4/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Fatores de Tempo
10.
Am J Respir Cell Mol Biol ; 50(6): 1010-20, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24328827

RESUMO

Pulmonary arterial smooth muscle cell (PASMC) proliferation and migration are important contributors to the vascular remodeling that occurs during development of pulmonary hypertension. We previously demonstrated that aquaporin (AQP)1, a member of the water channel family of proteins, was expressed in PASMCs and was necessary for hypoxia-induced migration; however, the mechanism by which AQP1 controls this response is unclear. The C-terminal tail of AQP1 contains putative calcium (EF-hand) and protein binding sites. Thus, we wanted to explore whether the C-terminal tail or the EF-hand motif of AQP1 was required for migration and proliferation. Rat PASMCs were isolated from distal pulmonary arteries, and proliferation and migration were measured using BrdU incorporation and transwell filters, respectively. To deplete AQP1, PASMCs were transfected with AQP1 small interference RNA (siRNA) or nontargeting siRNA. Knockdown of AQP1 reduced basal proliferation and hypoxia-induced migration and proliferation in PASMCs. In subsequent experiments, wild-type AQP1, AQP1 lacking the entire cytoplasmic C-terminal tail, or AQP1 with a mutation in the EF-hand motif were expressed in PASMCs using adenoviral constructs. For all AQP1 constructs, infection increased AQP1 protein levels, water permeability, and the change in cell volume induced by hypotonic challenge. Infection with wild-type and EF-hand mutated AQP1, but not C-terminal-deleted AQP1, increased PASMC migration and proliferation. Our results suggest that AQP1 controls proliferation and migration in PASMCs and that the mechanism requires the C-terminal tail of the protein but is independent of water transport or the EF-hand motif.


Assuntos
Aquaporina 1/metabolismo , Movimento Celular/fisiologia , Células Musculares/fisiologia , Artéria Pulmonar/fisiologia , Animais , Aquaporina 1/genética , Cálcio/metabolismo , Processos de Crescimento Celular/genética , Processos de Crescimento Celular/fisiologia , Hipóxia Celular/fisiologia , Movimento Celular/genética , Fluoresceínas/química , Técnicas de Silenciamento de Genes , Masculino , Células Musculares/metabolismo , Mutação , Artéria Pulmonar/metabolismo , Ratos , Ratos Wistar , Água/metabolismo
11.
Am J Respir Cell Mol Biol ; 48(5): 635-46, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23349051

RESUMO

Acute respiratory distress syndrome (ARDS) causes significant morbidity and mortality. Exacerbating factors increasing the risk of ARDS remain unknown. Supplemental oxygen is often necessary in both mild and severe lung disease. The potential effects of supplemental oxygen may include augmentation of lung inflammation by inhibiting anti-inflammatory pathways in alveolar macrophages. We sought to determine oxygen-derived effects on the anti-inflammatory A2A adenosinergic (ADORA2A) receptor in macrophages, and the role of the ADORA2A receptor in lung injury. Wild-type (WT) and ADORA2A(-/-) mice received intratracheal lipopolysaccharide (IT LPS), followed 12 hours later by continuous exposure to 21% oxygen (control mice) or 60% oxygen for 1 to 3 days. We measured the phenotypic endpoints of lung injury and the alveolar macrophage inflammatory state. We tested an ADORA2A-specific agonist, CGS-21680 hydrochloride, in LPS plus oxygen-exposed WT and ADORA2A(-/-) mice. We determined the specific effects of myeloid ADORA2A, using chimera experiments. Compared with WT mice, ADORA2A(-/-) mice exposed to IT LPS and 60% oxygen demonstrated significantly more histologic lung injury, alveolar neutrophils, and protein. Macrophages from ADORA2A(-/-) mice exposed to LPS plus oxygen expressed higher concentrations of proinflammatory cytokines and cosignaling molecules. CGS-21680 prevented the oxygen-induced augmentation of lung injury after LPS only in WT mice. Chimera experiments demonstrated that the transfer of WT but not ADORA2A(-/-) bone marrow cells into irradiated ADORA2A(-/-) mice reduced lung injury after LPS plus oxygen, demonstrating myeloid ADORA2A protection. ADORA2A is protective against lung injury after LPS and oxygen. Oxygen after LPS increases macrophage activation to augment lung injury by inhibiting the ADORA2A pathway.


Assuntos
Lesão Pulmonar Aguda/metabolismo , Macrófagos Alveolares/metabolismo , Oxigênio/toxicidade , Receptor A2A de Adenosina/metabolismo , Lesão Pulmonar Aguda/induzido quimicamente , Lesão Pulmonar Aguda/imunologia , Adenosina/análogos & derivados , Adenosina/farmacologia , Agonistas do Receptor A2 de Adenosina/farmacologia , Animais , Líquido da Lavagem Broncoalveolar , Células Cultivadas , Quimiocinas/metabolismo , Técnicas de Inativação de Genes , Mediadores da Inflamação/fisiologia , Lipopolissacarídeos/farmacologia , Pulmão/efeitos dos fármacos , Pulmão/imunologia , Pulmão/patologia , Macrófagos Alveolares/efeitos dos fármacos , Macrófagos Alveolares/imunologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Oxigenoterapia , Fenetilaminas/farmacologia , Receptor A2A de Adenosina/genética
12.
Nanotoxicology ; 7(6): 1143-51, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-22783847

RESUMO

The respiratory system is one of the portals of entry into the body, and hence inhalation of engineered nanomaterials is an important route of exposure. The broad range of physicochemical properties that influence biological responses necessitate the systematic study to contribute to understanding occupational exposure. Here, we report on the influence of nanoparticle charge and dose on human airway epithelial cells, and show that this platform can be used to evaluate consequences of exposure to engineered nanomaterials.


Assuntos
Brônquios/citologia , Células Epiteliais/metabolismo , Pontos Quânticos/química , Pontos Quânticos/metabolismo , Transporte Biológico , Compostos de Cádmio/química , Células Cultivadas , Células Epiteliais/efeitos dos fármacos , Humanos , Compostos de Selênio/química , Propriedades de Superfície
13.
Tissue Barriers ; 1(4): e25248, 2013 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-24665410

RESUMO

Chronic obstructive pulmonary disease (COPD) causes significant morbidity and mortality. Cigarette smoke, the most common risk factor for COPD, induces airway and alveolar epithelial barrier permeability and initiates an innate immune response. Changes in abundance of aquaporin 5 (AQP5), a water channel, can affect epithelial permeability and immune response after cigarette smoke exposure. To determine how AQP5-derived epithelial barrier modulation affects epithelial immune response to cigarette smoke and development of emphysema, WT and AQP5(-/-) mice were exposed to cigarette smoke (CS). We measured alveolar cell counts and differentials, and assessed histology, mean-linear intercept (MLI), and surface-to-volume ratio (S/V) to determine severity of emphysema. We quantified epithelial-derived signaling proteins for neutrophil trafficking, and manipulated AQP5 levels in an alveolar epithelial cell line to determine specific effects on neutrophil transmigration after CS exposure. We assessed paracellular permeability and epithelial turnover in response to CS. In contrast to WT mice, AQP5(-/-) mice exposed to 6 months of CS did not demonstrate a significant increase in MLI or a significant decrease in S/V compared with air-exposed mice, conferring protection against emphysema. After sub-acute (4 weeks) and chronic (6 mo) CS exposure, AQP5(-/-) mice had fewer alveolar neutrophil but similar lung neutrophil numbers as WT mice. The presence of AQP5 in A549 cells, an alveolar epithelial cell line, was associated with increase neutrophil migration after CS exposure. Compared with CS-exposed WT mice, neutrophil ligand (CD11b) and epithelial receptor (ICAM-1) expression were reduced in CS-exposed AQP5(-/-) mice, as was secreted LPS-induced chemokine (LIX), an epithelial-derived neutrophil chemoattractant. CS-exposed AQP5(-/-) mice demonstrated decreased type I pneumocytes and increased type II pneumocytes compared with CS-exposed WT mice suggestive of enhanced epithelial repair. Absence of AQP5 protected against CS-induced emphysema with reduced epithelial permeability, neutrophil migration, and altered epithelial cell turnover which may enhance repair.

14.
PLoS One ; 7(6): e38717, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22715407

RESUMO

Aquaporin-5 (AQP5) is a water-specific channel located on the apical surface of airway epithelial cells. In addition to regulating transcellular water permeability, AQP5 can regulate paracellular permeability, though the mechanisms by which this occurs have not been determined. Microtubules also regulate paracellular permeability. Here, we report that AQP5 promotes microtubule assembly and helps maintain the assembled microtubule steady state levels with slower turnover dynamics in cells. Specifically, reduced levels of AQP5 correlated with lower levels of assembled microtubules and decreased paracellular permeability. In contrast, overexpression of AQP5 increased assembly of microtubules, with evidence of increased MT stability, and promoted the formation of long straight microtubules in the apical domain of the epithelial cells. These findings indicate that AQP5-mediated regulation of microtubule dynamics modulates airway epithelial barrier properties and epithelial function.


Assuntos
Aquaporina 5/metabolismo , Permeabilidade da Membrana Celular/fisiologia , Células Epiteliais/metabolismo , Microtúbulos/metabolismo , Aquaporina 5/genética , Linhagem Celular Transformada , Células Epiteliais/citologia , Humanos , Microtúbulos/genética
15.
Am J Respir Cell Mol Biol ; 45(1): 120-6, 2011 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-20870893

RESUMO

Epithelial cells have the ability to regulate paracellular permeability dynamically in response to extracellular stimuli. With every respiratory effort, airway epithelial cells are exposed to both physiologic as well as pathologic stimuli, and regulation of the epithelial barrier in response to these stimuli is crucial to respiratory function. We report that increased membrane septin-2 localization mediates decreases in paracellular permeability by altering cortical actin arrangement in human airway epithelial cells. This phenomenon occurs in response to both physiologic levels of shear stress and a pathologic stimulus, particular matter exposure. The resulting changes in barrier function in response to septin-2 redistribution have a significant impact on the ability of the apical ligand, epidermal growth factor, to interact with its receptor, epidermal growth factor receptor, which is segregated to the basolateral side in airway epithelial cells. This suggests that the dynamic regulation of the epithelial barrier function is essential in regulating signaling responses to extracellular stimuli. These findings indicate that septin-2 plays a fundamental role in regulating barrier function by altering cortical actin expression.


Assuntos
Membrana Celular/metabolismo , Células Epiteliais/metabolismo , Mucosa Respiratória/metabolismo , Actinas/metabolismo , Animais , Linhagem Celular , Membrana Celular/patologia , Cães , Fator de Crescimento Epidérmico/metabolismo , Células Epiteliais/patologia , Regulação da Expressão Gênica , Humanos , Transporte Proteico , Mucosa Respiratória/patologia , Septinas , Transdução de Sinais
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA