RESUMO
Prostatic smooth muscle cells (pSMCs) differentiation is a key factor for prostatic homeostasis, with androgens exerting multiple effects on these cells. Here, we demonstrated that the myodifferentiator complex Srf/Myocd is up-regulated by testosterone in a dose-dependent manner in primary cultures of rat pSMCs, which was associated to the increase in Acta2, Cnn1, and Lmod1 expressions. Blocking Srf or Myocd by siRNAs inhibited the myodifferentiator effect of testosterone. While LPS led to a dedifferentiated phenotype in pSMCs, characterized by down-regulation of Srf/Myocd and smooth muscle cell (SMC)-restricted genes, endotoxin treatment on Myocd-overexpressing cells did not result in phenotypic alterations. Testosterone at a physiological dose was able to restore the muscular phenotype by normalizing Srf/Myocd expression in inflammation-induced dedifferentiated pSMCs. Moreover, the androgen reestablished the proliferation rate and IL-6 secretion increased by LPS. These results provide novel evidence regarding the myodifferentiating role of testosterone on SMCs by modulating Srf/Myocd. Thus, androgens preserve prostatic SMC phenotype, which is essential to maintain the normal structure and function of the prostate. J. Cell. Physiol. 232: 2806-2817, 2017. © 2016 Wiley Periodicals, Inc.
Assuntos
Desdiferenciação Celular/efeitos dos fármacos , Miócitos de Músculo Liso/efeitos dos fármacos , Proteínas Nucleares/metabolismo , Testosterona/farmacologia , Transativadores/metabolismo , Fatores de Transcrição/metabolismo , Actinas/metabolismo , Animais , Proteínas de Ligação ao Cálcio/metabolismo , Proliferação de Células/efeitos dos fármacos , Células Cultivadas , Relação Dose-Resposta a Droga , Interleucina-6/metabolismo , Lipopolissacarídeos/farmacologia , Masculino , Proteínas dos Microfilamentos/metabolismo , Miócitos de Músculo Liso/metabolismo , Proteínas Nucleares/genética , Fenótipo , Próstata , Interferência de RNA , Ratos Wistar , Transdução de Sinais/efeitos dos fármacos , Transativadores/genética , Fatores de Transcrição/genética , Transfecção , CalponinasRESUMO
Prostate smooth muscle cells (pSMCs) are capable of responding to inflammatory stimuli by secreting proinflammatory products, which causes pSMCs to undergo dedifferentiation. Although it has been proposed that androgens decrease proinflammatory molecules in many cells and under various conditions, the role of testosterone in the prostate inflammatory microenvironment is still unclear. Therefore, our aim was to evaluate if testosterone was able to modulate the pSMCs response to bacterial LPS by stimulating primary pSMC cultures, containing testosterone or vehicle, with LPS (1 or 10 µg/ml) for 24-48 h. The LPS challenge induced pSMCs dedifferentiation as evidenced by a decrease of calponin and alpha smooth muscle actin along with an increase of vimentin in a dose-dependent manner, whereas testosterone abrogated these alterations. Additionally, an ultrastructural analysis showed that pSMCs acquired a secretory profile after LPS and developed proteinopoietic organelles, while pSMCs preincubated with testosterone maintained a more differentiated phenotype. Testosterone downregulated the expression of surface TLR4 in control cells and inhibited any increase after LPS treatment. Moreover, testosterone prevented IκB-α degradation and the LPS-induced NF-κB nuclear translocation. Testosterone also decreased TNF-α and IL6 production by pSMCs after LPS as quantified by ELISA. Finally, we observed that testosterone inhibited the induction of pSMCs proliferation incited by LPS. Taken together, these results indicate that testosterone reduced the proinflammatory pSMCs response to LPS, with these cells being less reactive in the presence of androgens. In this context, testosterone might have a homeostatic role by contributing to preserve a contractile phenotype on pSMCs under inflammatory conditions.
Assuntos
Miócitos de Músculo Liso/citologia , Miócitos de Músculo Liso/metabolismo , Próstata/citologia , Próstata/metabolismo , Testosterona/metabolismo , Receptor 4 Toll-Like/metabolismo , Animais , Diferenciação Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Citocinas/biossíntese , Mediadores da Inflamação/metabolismo , Lipopolissacarídeos/farmacologia , Masculino , Modelos Biológicos , Miócitos de Músculo Liso/efeitos dos fármacos , NF-kappa B/metabolismo , Fenótipo , Próstata/efeitos dos fármacos , Ratos , Ratos Wistar , Testosterona/farmacologiaRESUMO
Bronchiolar Clara cells play a critical role in lung homoeostasis. The main goal of this study was to evaluate the effects of chronic allergy on these cells and the efficacy of budesonide (BUD) and montelukast (MK) in restoring their typical phenotypes after ovalbumin-induced chronic allergy in mice. Chronic allergy induced extensive bronchiolar Alcian blue-periodic acid-Schiff (AB/PAS)-positive metaplasia. In addition, cells accumulated numerous big electron-lucent granules negative for Clara cell main secretory protein (CC16), and consequently, CC16 was significantly reduced in bronchoalveolar lavage. A concomitant reduction in SP-D and CYP2E1 content was observed. The phenotypic changes induced by allergy were pharmacologically reversed by both treatments; MK was more efficient than BUD in doing so. MK decreased AB/PAS reactivity to control levels whereas they remained persistently elevated after BUD. Moreover, most non-ciliated cells recovered their normal morphology after MK, whereas for BUD normal cells coexisted with 'transitional' cells that contained remnant mucous granules and stained strongly for CC16 and SP-D. Glucocorticoids were also less able to reduce inflammatory infiltration and maintained higher percentage of neutrophils, which may have contributed to prolonged mucin expression. These results show that chronic allergy-induced mucous metaplasia of Clara cells affects their defensive mechanisms. However, anti-inflammatory treatments were able to re-establish the normal phenotype of Clara cell, with MK being more efficient at restoring a normal profile than BUD. This study highlights the role of epithelial cells in lung injuries and their contribution to anti-inflammatory therapies.
Assuntos
Acetatos/uso terapêutico , Asma/tratamento farmacológico , Asma/patologia , Brônquios/patologia , Budesonida/uso terapêutico , Fenótipo , Quinolinas/uso terapêutico , Acetatos/farmacologia , Animais , Antiasmáticos/farmacologia , Antiasmáticos/uso terapêutico , Anti-Inflamatórios/farmacologia , Anti-Inflamatórios/uso terapêutico , Asma/induzido quimicamente , Brônquios/efeitos dos fármacos , Brônquios/metabolismo , Budesonida/farmacologia , Doença Crônica , Ciclopropanos , Citocromo P-450 CYP2E1/metabolismo , Modelos Animais de Doenças , Epitélio/efeitos dos fármacos , Epitélio/metabolismo , Epitélio/patologia , Feminino , Camundongos , Camundongos Endogâmicos BALB C , Ovalbumina/efeitos adversos , Proteína D Associada a Surfactante Pulmonar/metabolismo , Quinolinas/farmacologia , Sulfetos , Uteroglobina/metabolismoRESUMO
This paper describes the development of a coating for cotton and polypropylene (PP) fabrics based on a polymeric matrix embedded with cuprous oxide nanoparticles (Cu2O@SDS NPs) in order to inactivate SARS-CoV-2 and manufactured by a simple process using a dip-assisted layer-by-layer technology, at low curing temperature and without the need for expensive equipment, capable of achieving disinfection rates of up to 99%. The polymeric bilayer coating makes the surface of the fabrics hydrophilic, enabling the transportation of the virus-infected droplets to achieve the rapid inactivation of SARS-CoV-2 by contact with the Cu2O@SDS NPs incorporated in the coated fabrics.
Assuntos
COVID-19 , Nanopartículas , Humanos , SARS-CoV-2 , COVID-19/prevenção & controle , Têxteis , PolímerosRESUMO
BACKGROUND: Prostate smooth muscle cells (SMCs) are strongly involved in the development and progression of benign prostatic hyperplasia and prostate cancer. However, their participation in prostatitis has not been completely elucidated. Thus, we aimed to characterize the response of normal SMC to bacterial lipopolysaccharide (LPS). METHODS: Primary prostate SMCs from normal rats were stimulated with LPS (0.1, 1, or 10 µg/ml) for 24 or 48 hr. The phenotype was evaluated by electron microscopy, immunofluorescence, and Western blot of SMCα-actin (ACTA2), calponin, vimentin, and tenascin-C, while the innate immune response was assessed by immunodetection of TLR4, CD14, and nuclear NF-κB. The secretion of TNFα and IL6 was determined using ELISA. RESULTS: Bacterial LPS induces SMCs to develop a secretory phenotype including dilated rough endoplasmic reticulum cisternae with well-developed Golgi complexes. Furthermore, SMCs displayed a decrease in ACTA2 and calponin, and an increase in vimentin levels after LPS challenge. The co-expression of ACTA2 and vimentin, together with the induction of tenascin-C expression indicate that a myofibroblastic-like phenotype was induced by the endotoxin. Moreover, LPS elicited a TLR4 increase, with a peak in NF-κB activation occurring after 10 min of treatment. Finally, LPS stimulated the secretion of IL6 and TNFα. CONCLUSIONS: Prostate SMCs are capable of responding to LPS in vitro by dedifferentiating from a contractile to a miofibroblastic-like phenotype and secreting cytokines, with the TLR4 signaling pathway being involved in this response. In this way, prostate SMCs may contribute to the pathophysiology of inflammatory diseases by modifying the epithelial-stromal interactions.
Assuntos
Desdiferenciação Celular/efeitos dos fármacos , Lipopolissacarídeos/farmacologia , Miócitos de Músculo Liso/efeitos dos fármacos , Próstata/efeitos dos fármacos , Animais , Western Blotting , Desdiferenciação Celular/fisiologia , Proliferação de Células/efeitos dos fármacos , Células Cultivadas , Ensaio de Imunoadsorção Enzimática , Imunofluorescência , Imunidade Inata/efeitos dos fármacos , Interleucina-6/metabolismo , Receptores de Lipopolissacarídeos/metabolismo , Masculino , Miócitos de Músculo Liso/metabolismo , NF-kappa B/metabolismo , Fosforilação , Próstata/citologia , Próstata/metabolismo , Ratos , Ratos Wistar , Receptor 4 Toll-Like/metabolismo , Fator de Necrose Tumoral alfa/metabolismoRESUMO
BACKGROUND: It has been proposed that prostatic inflammation plays a pivotal role in the pathophysiology of benign hyperplasia and prostate cancer. However, little information is available about the prostatic reaction to bacterial compounds in vivo. Our aim was therefore to evaluate the early effects of bacterial infection on rat ventral prostate compartments. METHODS: Using a rat model of acute bacterial prostatitis by Escherichia coli, we analyzed the histological and ultrastructural changes in the prostate at 24, 48, and 72 hr postinfection. Prostatic tissues were immunostained for prostatic binding protein (PBP), ACTA2, ErbB1, and ErbB2 receptors, TUNEL, and markers of cell proliferation. Dot and Western blots for PBP, ACTA2, ErbB1, ErbB2, and TGFbeta1 were also performed. RESULTS: The prostatic epithelium became hypertrophied, with increases in PBP and ErbB1 expression at 24 hr postinfection. Moreover, inflammation induced the expression of ErbB2, a receptor strongly involved in carcinogenesis. These alterations were more pronounced at 48 hr, but the epithelium also showed apoptosis and finally atrophy at 72 hr postinfection, with a decrease in PBP and ErbB receptors. Interestingly, the epithelial cells exhibited a high level of proliferation in response to the bacteria. The stromal reaction to acute inflammation was initially characterized by smooth muscle hypertrophy. Afterwards, muscle cells acquired a secretory phenotype, with a reduction in ACTA2 at 72 hr postinfection. CONCLUSIONS: Prostatic inflammation, even at the early stages, promotes atrophic and proliferative changes, and the upregulation of ErbB receptors together with dedifferentiation of smooth muscle cells. These data suggest that repetitive reinfections could lead to uncontrolled growth in the prostate gland.
Assuntos
Infecções por Escherichia coli/patologia , Escherichia coli/imunologia , Próstata/patologia , Prostatite/patologia , Actinas/metabolismo , Animais , Apoptose/fisiologia , Western Blotting , Processos de Crescimento Celular/fisiologia , Células Epiteliais/metabolismo , Células Epiteliais/patologia , Receptores ErbB/biossíntese , Receptores ErbB/metabolismo , Infecções por Escherichia coli/imunologia , Infecções por Escherichia coli/metabolismo , Infecções por Escherichia coli/microbiologia , Imuno-Histoquímica , Marcação In Situ das Extremidades Cortadas , Masculino , Microscopia Eletrônica , Proteína de Ligação a Fosfatidiletanolamina/biossíntese , Proteína de Ligação a Fosfatidiletanolamina/metabolismo , Próstata/imunologia , Próstata/metabolismo , Próstata/microbiologia , Prostatite/imunologia , Prostatite/metabolismo , Prostatite/microbiologia , Ratos , Ratos Wistar , Células Estromais/metabolismo , Células Estromais/patologia , Fator de Crescimento Transformador beta1/metabolismoRESUMO
In spite of physiopathogenic and therapeutic advances, asthma remains uncontrolled. The purpose of this test is to assess whether the instruments commonly used in the management of asthma are sufficient tools to control asthma, comparing the information provided by clinical evidence with cellular inflammatory parameters obtained through the analysis of induced sputum. We studied 15 asthmatics under treatment, which were evaluated the asthma control status (ACS) by clinical and spirometrical criteria, according to GINA recommendations. Then each patient underwent to obtain a sample of induced sputum (IE) and it was further analysed as a previously validated technique. From the total number of patients, 7 were total controlled patients according to ACS; only 2 of them had a normal IE cellular pattern while the other 5 presented an inflammatory profile in the differential cells count of the IE, forced to make adjustments in the anti-inflammatory treatment. One partially controlled patient by ACS, revealed inflammatory parameters in IE allowing modify the therapeutic schema. In 7 not controlled patients by ACS, the cellular inflammatory characteristics in IE, allowed modify therapeutic strategy which achieved control of the disease. We concluded that inflamommetry by IE cellular analysis is the tool that contributes to optimize the treatment and achieve true control of the disease. We suggest including this procedure in clinical practice and proposing a strategy for the management of asthma.
Assuntos
Asma/tratamento farmacológico , Asma/patologia , Escarro/citologia , Testes de Provocação Brônquica , Doença Crônica , Eosinófilos/patologia , Feminino , Humanos , Masculino , Reprodutibilidade dos Testes , EspirometriaRESUMO
Allergic asthma is the most common phenotype of the pathology, having an early-onset in childhood and producing a Th2-driven airways remodeling process that leads to symptoms and pathophysiological changes. The avoidance of aeroallergen exposure in early life has been shown to prevent asthma, but without repeated success and with the underlying preventive mechanisms at the beginning of asthma far to be fully recognized. In the present study, we aimed to evaluate if neonatal LPS-induced boost in epithelial host defenses contribute to prevent OVA-induced asthma in adult mice. To this, we focused on the response of bronchiolar club cells (CC), which are highly specialized in maintaining the epithelial homeostasis in the lung. In these cells, neonatal LPS administration increased the expression of TLR4 and TNFα, as well as the immunodulatory/antiallergic proteins: club cell secretory protein (CCSP) and surfactant protein D (SP-D). LPS also prevented mucous metaplasia of club cells and reduced the epidermal growth factor receptor (EGFR)-dependent mucin overproduction, with mice displaying normal breathing patterns after OVA challenge. Furthermore, the overexpression of the epithelial Th2-related molecule TSLP was blunted, and normal TSLP and IL-4 levels were found in the bronchoalveolar lavage. A lower eosinophilia was detected in LPS-pretreated mice, along with an increase in phagocytes and regulatory cells (CD4+CD25+FOXP3+ and CD4+IL-10+), together with higher levels of IL-12 and TNFα. In conclusion, our study demonstrates stable asthma-preventive epithelial effects promoted by neonatal LPS stimulation, leading to the presence of regulatory cells in the lung. These anti-allergic dynamic mechanisms would be overlaid in the epithelium, favored by an adequate epidemiological environment, during the development of asthma.
Assuntos
Asma/imunologia , Bronquíolos/efeitos dos fármacos , Bronquíolos/imunologia , Citocinas/metabolismo , Epitélio/imunologia , Imunidade Inata , Lipopolissacarídeos/imunologia , Lipopolissacarídeos/farmacologia , Alérgenos/imunologia , Animais , Animais Recém-Nascidos , Asma/prevenção & controle , Modelos Animais de Doenças , Epitélio/efeitos dos fármacos , Camundongos , Camundongos Endogâmicos BALB C , Ovalbumina/imunologia , Ovalbumina/farmacologia , Linfócitos T Reguladores/efeitos dos fármacos , Linfócitos T Reguladores/imunologiaRESUMO
Androgen signaling in prostate smooth muscle cells (pSMCs) is critical for the maintenance of prostate homeostasis, the alterations of which are a central aspect in the development of pathological conditions. Testosterone can act through the classic androgen receptor (AR) in the cytoplasm, eliciting genomic signaling, or through different types of receptors located at the plasma membrane for nongenomic signaling. We aimed to find evidence of nongenomic testosterone-signaling mechanisms in pSMCs and their participation in cell proliferation, differentiation, and the modulation of the response to lipopolysaccharide. We demonstrated that pSMCs can respond to testosterone by a rapid activation of ERK1/2 and Akt. Furthermore, a pool of ARs localized at the cell surface of pSMCs is responsible for a nongenomic testosterone-induced increase in cell proliferation. Through membrane receptor stimulation, testosterone favors a muscle phenotype, indicated by an increase in smooth muscle markers. We also showed that the anti-inflammatory effects of testosterone, capable of attenuating lipopolysaccharide-induced proinflammatory actions, are promoted only by receptors located inside the cell. We postulate that testosterone might perform prohomeostatic effects through intracellular-initiated mechanisms by modulating cell proliferation and inflammation, whereas some pathological, hyperproliferative actions would be induced by membrane-initiated nongenomic signaling in pSMCs.
Assuntos
Músculo Liso/efeitos dos fármacos , Miócitos de Músculo Liso/efeitos dos fármacos , Próstata/efeitos dos fármacos , Receptores Androgênicos/metabolismo , Testosterona/farmacologia , Animais , Células Cultivadas , Masculino , Músculo Liso/metabolismo , Miócitos de Músculo Liso/metabolismo , Próstata/citologia , Próstata/metabolismo , Ratos Wistar , Transdução de Sinais/efeitos dos fármacos , Distribuição TecidualRESUMO
Neutrophils are major effectors of acute inflammation against infection and tissue damage, with ability to adapt their phenotype according to the microenvironment. Although sex hormones regulate adaptive immune cells, which explains sex differences in immunity and infection, little information is available about the effects of androgens on neutrophils. We therefore aimed to examine neutrophil recruitment and plasticity in androgen-dependent and -independent sites under androgen manipulation. By using a bacterial model of prostate inflammation, we showed that neutrophil recruitment was higher in testosterone-treated rats, with neutrophil accumulation being positively correlated to serum levels of testosterone and associated to stronger inflammatory signs and tissue damage. Testosterone also promoted LPS-induced neutrophil recruitment to the prostate, peritoneum, and liver sinusoids, as revealed by histopathology, flow cytometry, and intravital microscopy. Strikingly, neutrophils in presence of testosterone exhibited an impaired bactericidal ability and a reduced myeloperoxidase activity. This inefficient cellular profile was accompanied by high expression of the anti-inflammatory cytokines IL10 and TGFß1, which is compatible with the "N2-like" neutrophil phenotype previously reported in the tumor microenvironment. These data reveal an intriguing role for testosterone promoting inefficient, anti-inflammatory neutrophils that prolong bacterial inflammation, generating a pathogenic environment for several conditions. However, these immunomodulatory properties might be beneficially exploited in autoimmune and other non-bacterial diseases.
Assuntos
Androgênios/metabolismo , Infecções por Escherichia coli/imunologia , Neutrófilos/imunologia , Prostatite/imunologia , Testosterona/metabolismo , Infecções Urinárias/imunologia , Escherichia coli Uropatogênica/fisiologia , Androgênios/administração & dosagem , Animais , Células Cultivadas , Modelos Animais de Doenças , Humanos , Interleucina-10/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Infiltração de Neutrófilos , Ratos , Ratos Wistar , Testosterona/administração & dosagem , Fator de Crescimento Transformador beta/metabolismo , Microambiente TumoralRESUMO
In pituitary adenomas, early recurrences and resistance to conventional pharmacotherapies are common, but the mechanisms involved are still not understood. The high expression of epidermal growth factor receptor 2 (HER2)/extracellular signal-regulated kinase (ERK1/2) signal observed in human pituitary adenomas, together with the low levels of the antimitogenic transforming growth factor beta receptor 2 (TBR2), encouraged us to evaluate the effect of the specific HER2 inhibition with trastuzumab on experimental pituitary tumor cell growth and its effect on the antiproliferative response to TGFB1. Trastuzumab decreased the pituitary tumor growth as well as the expression of ERK1/2 and the cell cycle regulators CCND1 and CDK4. The HER2/ERK1/2 pathway is an attractive therapeutic target, but its intricate relations with other signaling modulators still need to be unraveled. Thus, we investigated possible cross-talk with TGFB signaling, which has not yet been studied in pituitary tumors. In tumoral GH3 cells, co-incubation with trastuzumab and TGFB1 significantly decreased cell proliferation, an effect accompanied by a reduction in ERK1/2 phosphorylation, an increase of SMAD2/3 activation. In addition, through immunoprecipitation assays, a diminution of SMAD2/3-ERK1/2 and an increase SMAD2/3-TGFBR1 interactions were observed when cells were co-incubated with trastuzumab and TGFB1. These findings indicate that blocking HER2 by trastuzumab inhibited pituitary tumor growth and modulated HER2/ERK1/2 signaling and consequently the anti-mitogenic TGFB1/TBRs/SMADs cascade. The imbalance between HER2 and TGFBRs expression observed in human adenomas and the response to trastuzumab on experimental tumor growth may make the HER2/ERK1/2 pathway an attractive target for future pituitary adenoma therapy.
Assuntos
Adenoma/metabolismo , Proliferação de Células/efeitos dos fármacos , Neoplasias Hipofisárias/metabolismo , Transdução de Sinais/efeitos dos fármacos , Proteínas Smad/metabolismo , Fator de Crescimento Transformador beta/metabolismo , Trastuzumab/farmacologia , Adenoma/patologia , Adulto , Ciclo Celular/efeitos dos fármacos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Fosforilação , Neoplasias Hipofisárias/patologia , Adulto JovemRESUMO
In spite of the numerous studies on chronic obstructive pulmonary disease (COPD), the cellular and molecular basis of the disease's development remain unclear. Neutrophils and eosinophils are known to be key players in COPD. Recently, neutrophil extracellular trap cell death (NETosis), a mechanism due to decondensation and extrusion of chromatin to form extracellular traps, has been demonstrated in COPD. However, there is limited knowledge about eosinophil extracellular trap cell death (EETosis) and its role in the pathogenesis of COPD. The aim of this study was to evaluate EETosis in stable COPD. Induced sputum obtained from healthy smokers and low exacerbation risk COPD A or B group patients or high exacerbation risk COPD C or D group patients were included. Samples were examined using electron microscopy and immunofluorescence. Healthy smokers (n=10) and COPD A (n=19) group exhibited neutrophilic or paucigranulocytic phenotypes, with NETosis being absent in these patients. In contrast, COPD B (n=29), with eosinophilic or mixed phenotypes, showed EETosis and incipient NETosis. COPD C (n=18) and COPD D groups (n=13) were differentiated from low exacerbation rate-COPD group by the abundant cellular debris, with COPD C group having an eosinophilic pattern and numerous cells undergoing EETosis. A hallmark of this group was the abundant released membranes that often appeared phagocytosed by neutrophils, which coincidentally exhibited early NETosis changes. The COPD D group included patients with a neutrophilic or mixed pattern, with abundant neutrophil extracellular trap-derived material. This study is the first to demonstrate EETosis at different stages of stable COPD. The results suggest a role for eosinophils in COPD pathophysiology, especially at the beginning and during the persistence of the disease, regardless of whether the patient quit smoking, with EETosis debris probably triggering uncontrolled NETosis. The main target of these findings should be young smokers with the potential to develop COPD.
Assuntos
Eosinófilos/ultraestrutura , Armadilhas Extracelulares/metabolismo , Pulmão/ultraestrutura , Neutrófilos/ultraestrutura , Doença Pulmonar Obstrutiva Crônica/patologia , Estudos de Casos e Controles , Morte Celular , Estudos Transversais , Eosinófilos/metabolismo , Feminino , Imunofluorescência , Volume Expiratório Forçado , Humanos , Pulmão/metabolismo , Pulmão/fisiopatologia , Masculino , Microscopia Confocal , Microscopia Eletrônica , Pessoa de Meia-Idade , Neutrófilos/metabolismo , Doença Pulmonar Obstrutiva Crônica/metabolismo , Doença Pulmonar Obstrutiva Crônica/fisiopatologia , Fumar/efeitos adversos , Abandono do Hábito de Fumar , Prevenção do Hábito de Fumar , Escarro/citologia , Escarro/metabolismo , Capacidade VitalRESUMO
Although pituitary adenomas represent 25% of intracranial tumors, they are usually benign, with the mechanisms by which these tumors usually avoid an invasive profile and metastatic growth development still remaining unclear. In this context, cellular senescence might constitute a plausible explanation for the benign nature of pituitary adenomas. In this study, we investigated the emergence of cellular senescence as a growth control mechanism during the progression of estrogen-induced pituitary tumors. The quantification of Ki67-immunopositive cells in the pituitaries of estrogenized male rats after 10, 20, 40, and 60 days revealed that the mitogenic potential rate was not sustained for the whole period analyzed and successively decreased after 10 days of estrogen exposure. In addition, the expression of cellular senescence features, such as the progressive rise in the enzymatic senescence-associated b-galactosidase (SA-b-gal) activity, IL6, IL1b, and TGFb expression, was observed throughout pituitary tumor development. Furthermore, tumoral pituitary cells also displayed nuclear pATM expression, indicating activated DNA damage signaling, with a significant increase in p21 expression also being detected. The associations among DNA damage signaling activation, SA-b-gal expression, and p21 may provide a reliable combination of senescence-associated markers for in vivo pituitary senescence detection. These results suggest a role for this cellular process in the regulation of pituitary cell growth. Thus, cellular senescence should be conceived as a contributing component to the benign nature of pituitary adenomas, thereby influencing the capability of the pituitary gland to avoid unregulated cell proliferation.
Assuntos
Senescência Celular/fisiologia , Estrogênios/toxicidade , Neoplasias Hipofisárias/patologia , Animais , Senescência Celular/efeitos dos fármacos , Progressão da Doença , Estrogênios/administração & dosagem , Masculino , Neoplasias Hipofisárias/induzido quimicamente , Ratos , Ratos Wistar , Transdução de SinaisRESUMO
Atopic asthma is a chronic allergic disease that involves T-helper type 2 (Th2)-inflammation and airway remodeling. Bronchiolar club cells (CC) and alveolar macrophages (AM) are sentinel cells of airway barrier against inhaled injuries, where allergy induces mucous metaplasia of CC and the alternative activation of AM, which compromise host defense mechanisms and amplify Th2-inflammation. As there is evidence that high levels of environmental endotoxin modulates asthma, the goal of this study was to evaluate if the activation of local host defenses by Lipopolysaccharide (LPS) previous to allergy development can contribute to preserving CC and AM protective phenotypes. Endotoxin stimulus before allergen exposition reduced hallmarks of allergic inflammation including eosinophil influx, Interleukin-4 and airway hyperreactivity, while the T-helper type 1 related cytokines IL-12 and Interferon-γ were enhanced. This response was accompanied by the preservation of the normal CC phenotype and the anti-allergic proteins Club Cell Secretory Protein (CCSP) and Surfactant-D, thereby leading to lower levels of CC metaplasia and preventing the increase of the pro-Th2 cytokine Thymic stromal lymphopoietin. In addition, classically activated alveolar macrophages expressing nitric oxide were promoted over the alternatively activated ones that expressed arginase-1. We verified that LPS induced a long-term overexpression of CCSP and the innate immune markers Toll-like receptor 4, and Tumor Necrosis Factor-α, changes that were preserved in spite of the allergen challenge. These results demonstrate that LPS pre-exposition modifies the local bronchioalveolar microenvironment by inducing natural anti-allergic mechanisms while reducing local factors that drive Th2 type responses, thus modulating allergic inflammation.
Assuntos
Asma/imunologia , Macrófagos Alveolares/imunologia , Mucosa Respiratória/citologia , Mucosa Respiratória/imunologia , Animais , Western Blotting , Modelos Animais de Doenças , Endotoxinas/imunologia , Endotoxinas/toxicidade , Ensaio de Imunoadsorção Enzimática , Feminino , Imunofluorescência , Imuno-Histoquímica , Camundongos , Camundongos Endogâmicos BALB C , Fenótipo , Uteroglobina/metabolismoRESUMO
Bronchiolar Clara cells are integral components of lung homeostasis, predominantly distributed in distal airways. In addition to the 16 kDa Clara cell protein, a major secretory product with anti-inflammatory effects, rat Clara cells express the glycan-binding protein galectin-3 and secrete it into the airways. Given the essential role of galectin-3 in the control of inflammation and the well-established function of glucocorticoids (GCs) in lung physiology, here we investigated whether galectin-3 is a target of the regulatory effects of GCs. Adult male rats were subjected to bilateral adrenalectomy and the lungs were processed for light and transmission electron microscopy, immunoelectron microscopy and Western blot analysis. Profound changes in bronchiolar Clara cells and macrophage morphology could be observed by electron microscopy after adrenalectomy. While specific galectin-3 staining was detected in the nucleus and cytoplasm of Clara cells and macrophages from control animals, cytoplasmic galectin-3 expression was dramatically reduced after adrenalectomy in both cell types. This effect was cell-specific as it did not affect expression of this lectin in ciliated cells. After dexamethasone treatment, galectin-3 expression increased significantly in the nucleus and cytoplasm of macrophages and Clara cells. Western blot analysis showed a clear decrease in galectin-3 expression in ADX animals, which was recovered after a 7-day treatment with dexamethasone. In peritoneal macrophages, galectin-3 expression was also dependent on the effects of GCs both in vivo and in vitro. Our results identify a cell type-specific control of galectin-3 synthesis by GCs in lung bronchiolar Clara cells and interstitial macrophages, which may provide an alternative mechanism by which GCs contribute to modulate the inflammatory response.