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1.
Contemp Clin Trials Commun ; 35: 101169, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37638227

RESUMO

Background: Sexual and gender minority (SGM) older adults and their care partners, compared to the general population, face unique vulnerabilities that exacerbate living with dementia, including elevated disparities in comorbidities, social isolation, and structural inequities, such as discrimination and lack of access to supports. Methods: This paper describes the virtual adaptation process of the first-ever randomized controlled clinical trial intervention, Aging with Pride: Innovations in Dementia Empowerment and Action (IDEA), that was designed for SGM older adults living with dementia and their care partners and built upon the foundation of RDAD and NHAS. Results: The virtual adaptation of IDEA was guided by the goals of accessibility, quality, ease of delivery, sustainability, and cultural relevance. The implementation required the development of a HIPPA-compliant online virtual platform, coach and participant virtual training, and modification of necessary intervention elements and materials, as needed. Based on the preliminary findings, the participants and intervention coaches responded well to the virtual adaptation of IDEA. When comparing to in-person delivery, the virtual delivery decreased attrition among both intervention participants and coaches. Discussion: The virtual adaptation of the IDEA intervention resulted in preliminary, unexpected, yet potentially important benefits, including the ability to expand the reach of the intervention and decreased attrition. Virtual interventions are an emerging field for people living with dementia and their care partners and additional systematic research is needed to fully assess the benefits and limitations as well as to evaluate if specific subgroups are better served by differing delivery modalities.

2.
Contemp Clin Trials ; 128: 107143, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-36893987

RESUMO

BACKGROUND: Heightened risks of cognitive impairment, disability, and barriers to care among sexual and gender minority (SGM) older adults are well documented. To date, culturally responsive evidence-based dementia interventions for this population do not exist. OBJECTIVE: This study describes the design of the first randomized controlled trial (RCT) testing a culturally responsive cognitive behavioral and empowerment intervention, Innovations in Dementia Empowerment and Action (IDEA), developed to address the unique needs of SGM older adults living with dementia and care partners. METHODS: IDEA is a culturally enhanced version of Reducing Disability in Alzheimer's Disease (RDAD), an efficacious, non-pharmaceutical intervention for people with dementia and care partners. We utilized a staggered multiple baseline design with the goal to enroll 150 dyads randomized into two arms of 75 dyads each, enhanced IDEA and standard RDAD. RESULTS: IDEA was adapted using findings from the longitudinal National Health, Aging, and Sexuality/Gender study, which identified modifiable factors for SGM older adults, including SGM-specific discrimination and stigma, health behaviors, and support networks. The adapted intervention employed the original RDAD strategies and enhanced them with culturally responsive empowerment practices designed to cultivate engagement, efficacy, and support mobilization. Outcomes include adherence to physical activity, reduction in perceived stress and stigma, and increased physical functioning, efficacy, social support, engagement, and resource use. CONCLUSION: IDEA addresses contemporary issues for underserved populations living with dementia and their care partners. Our findings will have important implications for marginalized communities by integrating and evaluating the importance of cultural responsiveness in dementia and caregiving interventions.


Assuntos
Doença de Alzheimer , Disfunção Cognitiva , Minorias Sexuais e de Gênero , Humanos , Idoso , Cuidadores/psicologia , Doença de Alzheimer/psicologia , Identidade de Gênero
3.
Conserv Physiol ; 9(1): coab007, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33833867

RESUMO

Changes in species composition and biomass of Arctic benthic communities are predicted to occur in response to environmental changes associated with oceanic warming and sea-ice loss. Such changes will likely impact ecosystem function, including flows of energy and organic material through the Arctic marine food web. Oxygen consumption rates can be used to quantify differences in metabolic demand among species and estimate the effects of shifting community structure on benthic carbon consumption. Closed-system respirometry using non-invasive oxygen optodes was conducted onboard the R/V Sikuliaq in June 2017 and 2018 on six dominant species of benthic macrofauna from the northern Bering and southern Chukchi Sea shelves, including five bivalve species (Macoma sp., Serripes groenlandicus, Astarte sp., Hiatella arctica and Nuculana pernula) and one amphipod species (Ampelisca macrocephala). Results revealed species-specific respiration rates with high metabolic demand for S. groenlandicus and A. macrocephala compared to that of the other species. For a hypothetical 0.1-g ash-free dry mass individual, the standard metabolic rate of S. groenlandicus would be 4.3 times higher than that of Astarte sp. Overall, carbon demand ranged from 8 to 475 µg C individual-1 day-1 for the species and sizes of individuals measured. The allometric scaling of respiration rate with biomass also varied among species. The scaling coefficient was similar for H. arctica, A. macrocephala and Astarte sp., while it was high for S. groenlandicus and low for Macoma sp. These results suggest that observed shifts in spatial distribution of the dominant macrofaunal taxa across this region will impact carbon demand of the benthic community. Hence, ecosystem models seeking to incorporate benthic system functionality may need to differentiate between communities that exhibit different oxygen demands.

4.
Am J Physiol Lung Cell Mol Physiol ; 310(3): L249-62, 2016 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-26637636

RESUMO

Pulmonary hypertension (PH) complicating chronic parenchymal lung disease, such as idiopathic pulmonary fibrosis, results in significant morbidity and mortality. Since the hypoxia-inducible factor (HIF) signaling pathway is important for development of pulmonary hypertension in chronic hypoxia, we investigated whether HIF signaling in vascular endothelium regulates development of PH related to pulmonary fibrosis. We generated a transgenic model in which HIF is deleted within vascular endothelial cells and then exposed these mice to chronic intraperitoneal bleomycin to induce PH associated with lung fibrosis. Although no differences in the degree of fibrotic remodeling were observed, we found that endothelial HIF-deficient mice were protected against development of PH, including right ventricle and pulmonary vessel remodeling. Similarly, endothelial HIF-deficient mice were protected from PH after a 4-wk exposure to normobaric hypoxia. In vitro studies of pulmonary vascular endothelial cells isolated from the HIF-targeted mice and controls revealed that endothelial HIF signaling increases endothelial cell expression of connective tissue growth factor, enhances vascular permeability, and promotes pulmonary artery smooth muscle cell proliferation and wound healing ability, all of which have the potential to impact the development of PH in vivo. Taken together, these studies demonstrate that vascular endothelial cell HIF signaling is necessary for development of hypoxia and pulmonary fibrosis associated PH. As such, HIF and HIF-regulated targets represent a therapeutic target in these conditions.


Assuntos
Células Endoteliais/metabolismo , Hipertensão Pulmonar/metabolismo , Fator 1 Induzível por Hipóxia/metabolismo , Artéria Pulmonar/metabolismo , Animais , Proliferação de Células/fisiologia , Células Cultivadas , Endotélio Vascular/metabolismo , Fibrose/etiologia , Hipertensão Pulmonar/complicações , Hipóxia/metabolismo , Camundongos Transgênicos , Músculo Liso Vascular/metabolismo , Remodelação Vascular/fisiologia
5.
Am J Respir Crit Care Med ; 191(4): 417-26, 2015 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-25389906

RESUMO

RATIONALE: Asymptomatic relatives of patients with familial interstitial pneumonia (FIP), the inherited form of idiopathic interstitial pneumonia, carry increased risk for developing interstitial lung disease. OBJECTIVES: Studying these at-risk individuals provides a unique opportunity to investigate early stages of FIP pathogenesis and develop predictive models of disease onset. METHODS: Seventy-five asymptomatic first-degree relatives of FIP patients (mean age, 50.8 yr) underwent blood sampling and high-resolution chest computed tomography (HRCT) scanning in an ongoing cohort study; 72 consented to bronchoscopy with bronchoalveolar lavage (BAL) and transbronchial biopsies. Twenty-seven healthy individuals were used as control subjects. MEASUREMENTS AND MAIN RESULTS: Eleven of 75 at-risk subjects (14%) had evidence of interstitial changes by HRCT, whereas 35.2% had abnormalities on transbronchial biopsies. No differences were noted in inflammatory cells in BAL between at-risk individuals and control subjects. At-risk subjects had increased herpesvirus DNA in cell-free BAL and evidence of herpesvirus antigen expression in alveolar epithelial cells (AECs), which correlated with expression of endoplasmic reticulum stress markers in AECs. Peripheral blood mononuclear cell and AEC telomere length were shorter in at-risk individuals than healthy control subjects. The minor allele frequency of the Muc5B rs35705950 promoter polymorphism was increased in at-risk subjects. Levels of several plasma biomarkers differed between at-risk subjects and control subjects, and correlated with abnormal HRCT scans. CONCLUSIONS: Evidence of lung parenchymal remodeling and epithelial dysfunction was identified in asymptomatic individuals at risk for FIP. Together, these findings offer new insights into the early pathogenesis of idiopathic interstitial pneumonia and provide an ongoing opportunity to characterize presymptomatic abnormalities that predict progression to clinical disease.


Assuntos
Doenças Pulmonares Intersticiais/diagnóstico , Fenótipo , Adulto , Idoso , Doenças Assintomáticas , Biomarcadores/metabolismo , Biópsia , Lavagem Broncoalveolar , Broncoscopia , Estudos de Casos e Controles , DNA Viral/análise , Feminino , Frequência do Gene , Marcadores Genéticos , Herpesviridae/genética , Herpesviridae/isolamento & purificação , Humanos , Pulmão/diagnóstico por imagem , Pulmão/metabolismo , Pulmão/patologia , Pulmão/virologia , Doenças Pulmonares Intersticiais/genética , Doenças Pulmonares Intersticiais/metabolismo , Doenças Pulmonares Intersticiais/virologia , Masculino , Pessoa de Meia-Idade , Mucina-5B/genética , Polimorfismo Genético , Estudos Prospectivos , Tomografia Computadorizada por Raios X
6.
Am J Respir Crit Care Med ; 187(6): 630-9, 2013 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-23306543

RESUMO

RATIONALE: Alveolar epithelial cells (AECs) play central roles in the response to lung injury and the pathogenesis of pulmonary fibrosis. OBJECTIVES: We aimed to determine the role of ß-catenin in alveolar epithelium during bleomycin-induced lung fibrosis. METHODS: Genetically modified mice were developed to selectively delete ß-catenin in AECs and were crossed to cell fate reporter mice that express ß-galactosidase (ßgal) in cells of AEC lineage. Mice were given intratracheal bleomycin (0.04 units) and assessed for AEC death, inflammation, lung injury, and fibrotic remodeling. Mouse lung epithelial cells (MLE12) with small interfering RNA knockdown of ß-catenin underwent evaluation for wound closure, proliferation, and bleomycin-induced cytotoxicity. MEASUREMENTS AND MAIN RESULTS: Increased ß-catenin expression was noted in lung parenchyma after bleomycin. Mice with selective deletion of ß-catenin in AECs had greater AEC death at 1 week after bleomycin, followed by increased numbers of fibroblasts and enhanced lung fibrosis as determined by semiquantitative histological scoring and total collagen content. However, no differences in lung inflammation or protein levels in bronchoalveolar lavage were noted. In vitro, ß-catenin-deficient AECs showed increased bleomycin-induced cytotoxicity as well as reduced proliferation and impaired wound closure. Consistent with these findings, mice with AEC ß-catenin deficiency showed delayed recovery after bleomycin. CONCLUSIONS: ß-Catenin in the alveolar epithelium protects against bleomycin-induced fibrosis. Our studies suggest that AEC survival and wound healing are enhanced through ß-catenin-dependent mechanisms. Activation of the developmentally important ß-catenin pathway in AECs appears to contribute to epithelial repair after epithelial injury.


Assuntos
Lesão Pulmonar/patologia , Alvéolos Pulmonares/fisiologia , Fibrose Pulmonar/patologia , beta Catenina/fisiologia , Animais , Bleomicina/efeitos adversos , Modelos Animais de Doenças , Epitélio , Marcação In Situ das Extremidades Cortadas , Lesão Pulmonar/induzido quimicamente , Camundongos , Camundongos Transgênicos , Fibrose Pulmonar/induzido quimicamente , Cicatrização/fisiologia
7.
Exp Lung Res ; 38(3): 124-34, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22394286

RESUMO

Idiopathic pulmonary fibrosis (IPF) is characterized by interstitial lung infiltrates, dyspnea, and progressive respiratory failure. Reports linking telomerase mutations to familial interstitial pneumonia (FIP) suggest that telomerase activity and telomere length maintenance are important in disease pathogenesis. To investigate the role of telomerase in lung fibrotic remodeling, intratracheal bleomycin was administered to mice deficient in telomerase reverse transcriptase (TERT) or telomerase RNA component (TERC) and to wild-type controls. TERT-deficient and TERC-deficient mice were interbred to the F6 and F4 generation, respectively, when they developed skin manifestations and infertility. Fibrosis was scored using a semiquantitative scale and total lung collagen was measured using a hydroxyprolinemicroplate assay. Telomere lengths were measured in peripheral blood leukocytes and isolated type II alveolar epithelial cells (AECs). Telomerase activity in type II AECs was measured using a real-time polymerase chain reaction (PCR)-based system. Following bleomycin, TERT-deficient and TERC-deficient mice developed an equivalent inflammatory response and similar lung fibrosis (by scoring of lung sections and total lung collagen content) compared to controls, a pattern seen in both early (F1) and later (F6 TERT and F4 TERC) generations. Telomere lengths were reduced in peripheral blood leukocytes and isolated type II AECs from F6 TERT-deficient and F4 TERC-deficient mice compared to controls. Telomerase deficiency in a murine model leads to telomere shortening, but does not predispose to enhanced bleomycin-induced lung fibrosis. Additional genetic or environmental factors may be necessary for development of fibrosis in the presence of telomerase deficiency.


Assuntos
Bleomicina/toxicidade , Fibrose Pulmonar Idiopática/induzido quimicamente , Fibrose Pulmonar Idiopática/enzimologia , Telomerase/deficiência , Homeostase do Telômero/efeitos dos fármacos , Remodelação das Vias Aéreas/efeitos dos fármacos , Remodelação das Vias Aéreas/genética , Animais , Antibióticos Antineoplásicos/toxicidade , Colágeno/metabolismo , Células Epiteliais/efeitos dos fármacos , Células Epiteliais/metabolismo , Feminino , Fibrose Pulmonar Idiopática/genética , Leucócitos/efeitos dos fármacos , Leucócitos/metabolismo , Pulmão/efeitos dos fármacos , Pulmão/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Mutação/genética , Pneumonia/induzido quimicamente , Pneumonia/genética , Pneumonia/metabolismo , Alvéolos Pulmonares/efeitos dos fármacos , Alvéolos Pulmonares/metabolismo , RNA/genética , Telomerase/genética , Telomerase/metabolismo , Homeostase do Telômero/genética , Encurtamento do Telômero/efeitos dos fármacos , Encurtamento do Telômero/genética
8.
Exp Lung Res ; 38(3): 135-46, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22394287

RESUMO

In addition to parenchymal fibrosis, fibrotic remodeling of the distal airways has been reported in interstitial lung diseases. Mechanisms of airway wall remodeling, which occurs in a variety of chronic lung diseases, are not well defined and current animal models are limited. The authors quantified airway remodeling in lung sections from subjects with idiopathic pulmonary fibrosis (IPF) and controls. To investigate intratracheal bleomycin as a potential animal model for fibrotic airway remodeling, the authors evaluated lungs from C57BL/6 mice after bleomycin treatment by histologic scoring for fibrosis and peribronchial inflammation, morphometric evaluation of subepithelial connective tissue volume density, TUNEL (terminal deoxynucleotidyl transferase dUTP-mediated nick-end labeling) assay, and immunohistochemistry for transforming growth factor ß1 (TGFß1), TGFß2, and the fibroblast marker S100A4. Lung mechanics were determined at 3 weeks post bleomycin. IPF lungs had small airway remodeling with increased bronchial wall thickness compared to controls. Similarly, bleomycin-treated mice developed dose-dependent airway wall inflammation and fibrosis and greater airflow resistance after high-dose bleomycin. Increased TUNEL(+) bronchial epithelial cells and peribronchial inflammation were noted by 1 week, and expression of TGFß1 and TGFß2 and accumulation of S100A4(+) fibroblasts correlated with airway remodeling in a bleomycin dose-dependent fashion. IPF is characterized by small airway remodeling in addition to parenchymal fibrosis, a pattern also seen with intratracheal bleomycin. Bronchial remodeling from intratracheal bleomycin follows a cascade of events including epithelial cell injury, airway inflammation, profibrotic cytokine expression, fibroblast accumulation, and peribronchial fibrosis. Thus, this model can be utilized to investigate mechanisms of airway remodeling.


Assuntos
Obstrução das Vias Respiratórias/induzido quimicamente , Remodelação das Vias Aéreas/efeitos dos fármacos , Bleomicina/toxicidade , Fibrose Pulmonar Idiopática/induzido quimicamente , Obstrução das Vias Respiratórias/genética , Obstrução das Vias Respiratórias/metabolismo , Obstrução das Vias Respiratórias/patologia , Remodelação das Vias Aéreas/genética , Remodelação das Vias Aéreas/fisiologia , Animais , Antibióticos Antineoplásicos/administração & dosagem , Antibióticos Antineoplásicos/toxicidade , Bleomicina/administração & dosagem , Modelos Animais de Doenças , Células Epiteliais/efeitos dos fármacos , Células Epiteliais/metabolismo , Células Epiteliais/patologia , Feminino , Fibroblastos/efeitos dos fármacos , Fibroblastos/metabolismo , Fibroblastos/patologia , Humanos , Fibrose Pulmonar Idiopática/genética , Fibrose Pulmonar Idiopática/metabolismo , Fibrose Pulmonar Idiopática/patologia , Inflamação/induzido quimicamente , Inflamação/genética , Inflamação/metabolismo , Inflamação/patologia , Pulmão/efeitos dos fármacos , Pulmão/metabolismo , Pulmão/patologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Proteína A4 de Ligação a Cálcio da Família S100 , Proteínas S100/genética , Proteínas S100/metabolismo , Fator de Crescimento Transformador beta1/genética , Fator de Crescimento Transformador beta1/metabolismo , Fator de Crescimento Transformador beta2/genética , Fator de Crescimento Transformador beta2/metabolismo
9.
Proc Natl Acad Sci U S A ; 108(26): 10562-7, 2011 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-21670280

RESUMO

Evidence of endoplasmic reticulum (ER) stress has been found in lungs of patients with familial and sporadic idiopathic pulmonary fibrosis. We tested whether ER stress causes or exacerbates lung fibrosis by (i) conditional expression of a mutant form of surfactant protein C (L188Q SFTPC) found in familial interstitial pneumonia and (ii) intratracheal treatment with the protein misfolding agent tunicamycin. We developed transgenic mice expressing L188Q SFTPC exclusively in type II alveolar epithelium by using the Tet-On system. Expression of L188Q SFTPC induced ER stress, as determined by increased expression of heavy-chain Ig binding protein (BiP) and splicing of X-box binding protein 1 (XBP1) mRNA, but no lung fibrosis was identified in the absence of a second profibrotic stimulus. After intratracheal bleomycin, L188Q SFTPC-expressing mice developed exaggerated lung fibrosis and reduced static lung compliance compared with controls. Bleomycin-treated L188Q SFTPC mice also demonstrated increased apoptosis of alveolar epithelial cells and greater numbers of fibroblasts in the lungs. With a complementary model, intratracheal tunicamycin treatment failed to induce lung remodeling yet resulted in augmentation of bleomycin-induced fibrosis. These data support the concept that ER stress produces a dysfunctional epithelial cell phenotype that facilitates fibrotic remodeling. ER stress pathways may serve as important therapeutic targets in idiopathic pulmonary fibrosis.


Assuntos
Retículo Endoplasmático/metabolismo , Pulmão/patologia , Fibrose Pulmonar/patologia , Animais , Apoptose/genética , Bleomicina/toxicidade , Peptídeos e Proteínas de Sinalização Intercelular , Pulmão/efeitos dos fármacos , Pulmão/metabolismo , Camundongos , Camundongos Transgênicos , Mutação , Peptídeos/genética , Fibrose Pulmonar/genética , Fibrose Pulmonar/metabolismo , Proteína C Associada a Surfactante Pulmonar , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Tunicamicina/toxicidade
10.
Am J Physiol Lung Cell Mol Physiol ; 300(6): L887-97, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21441353

RESUMO

The response of alveolar epithelial cells (AECs) to lung injury plays a central role in the pathogenesis of pulmonary fibrosis, but the mechanisms by which AECs regulate fibrotic processes are not well defined. We aimed to elucidate how transforming growth factor-ß (TGFß) signaling in lung epithelium impacts lung fibrosis in the intratracheal bleomycin model. Mice with selective deficiency of TGFß receptor 2 (TGFßR2) in lung epithelium were generated and crossed to cell fate reporter mice that express ß-galactosidase (ß-gal) in cells of lung epithelial lineage. Mice were given intratracheal bleomycin (0.08 U), and the following parameters were assessed: AEC death by terminal deoxynucleotidyl transferase dUTP-mediated nick-end labeling assay, inflammation by total and differential cell counts from bronchoalveolar lavage, fibrosis by scoring of trichrome-stained lung sections, and total lung collagen content. Mice with lung epithelial deficiency of TGFßR2 had improved AEC survival, despite greater lung inflammation, after bleomycin administration. At 3 wk after bleomycin administration, mice with epithelial TGFßR2 deficiency showed a significantly attenuated fibrotic response in the lungs, as determined by semiquantitatve scoring and total collagen content. The reduction in lung fibrosis in these mice was associated with a marked decrease in the lung fibroblast population, both total lung fibroblasts and epithelial-to-mesenchymal transition-derived (S100A4(+)/ß-gal(+)) fibroblasts. Attenuation of TGFß signaling in lung epithelium provides protection from bleomycin-induced fibrosis, indicating a critical role for the epithelium in transducing the profibrotic effects of this cytokine.


Assuntos
Bleomicina/efeitos adversos , Epitélio/metabolismo , Fibroblastos/metabolismo , Lesão Pulmonar/induzido quimicamente , Proteínas Serina-Treonina Quinases/fisiologia , Alvéolos Pulmonares/efeitos dos fármacos , Receptores de Fatores de Crescimento Transformadores beta/fisiologia , Fator de Crescimento Transformador beta/metabolismo , Animais , Antibióticos Antineoplásicos/efeitos adversos , Western Blotting , Proliferação de Células , Células Cultivadas , Modelos Animais de Doenças , Epitélio/efeitos dos fármacos , Epitélio/patologia , Fibroblastos/efeitos dos fármacos , Fibroblastos/patologia , Imunofluorescência , Lesão Pulmonar/metabolismo , Lesão Pulmonar/patologia , Camundongos , Camundongos Transgênicos , Pneumonia/induzido quimicamente , Pneumonia/metabolismo , Pneumonia/patologia , Alvéolos Pulmonares/metabolismo , Alvéolos Pulmonares/patologia , Fibrose Pulmonar/induzido quimicamente , Fibrose Pulmonar/metabolismo , Fibrose Pulmonar/patologia , Receptor do Fator de Crescimento Transformador beta Tipo II , Transdução de Sinais , beta-Galactosidase/metabolismo
11.
Am J Physiol Lung Cell Mol Physiol ; 299(4): L442-52, 2010 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-20562227

RESUMO

Single-dose intratracheal bleomycin has been instrumental for understanding fibrotic lung remodeling, but fails to recapitulate several features of idiopathic pulmonary fibrosis (IPF). Since IPF is thought to result from recurrent alveolar injury, we aimed to develop a repetitive bleomycin model that results in lung fibrosis with key characteristics of human disease, including alveolar epithelial cell (AEC) hyperplasia. Wild-type and cell fate reporter mice expressing ß-galactosidase in cells of lung epithelial lineage were given intratracheal bleomycin after intubation, and lungs were harvested 2 wk after a single or eighth biweekly dose. Lungs were evaluated for fibrosis and collagen content. Bronchoalveolar lavage (BAL) was performed for cell counts. TUNEL staining and immunohistochemistry were performed for pro-surfactant protein C (pro-SP-C), Clara cell 10 (CC-10), ß-galactosidase, S100A4, and α-smooth muscle actin. Lungs from repetitive bleomycin mice had marked fibrosis with prominent AEC hyperplasia, similar to usual interstitial pneumonia (UIP). Compared with single dosing, repetitive bleomycin mice had greater fibrosis by scoring, morphometry, and collagen content; increased TUNEL+ AECs; and reduced inflammatory cells in BAL. Sixty-four percent of pro-SP-C+ cells in areas of fibrosis expressed CC-10 in the repetitive model, suggesting expansion of a bronchoalveolar stem cell-like population. In reporter mice, 50% of S100A4+ lung fibroblasts were derived from epithelial mesenchymal transition compared with 33% in the single-dose model. With repetitive bleomycin, fibrotic remodeling persisted 10 wk after the eighth dose. Repetitive intratracheal bleomycin results in marked lung fibrosis with prominent AEC hyperplasia, features reminiscent of UIP.


Assuntos
Antibióticos Antineoplásicos/farmacologia , Bleomicina/farmacologia , Modelos Animais de Doenças , Células Epiteliais/efeitos dos fármacos , Fibrose Pulmonar Idiopática/induzido quimicamente , Animais , Apoptose , Líquido da Lavagem Broncoalveolar , Proliferação de Células , Células Cultivadas , Células Epiteliais/metabolismo , Fibroblastos/efeitos dos fármacos , Fibroblastos/metabolismo , Imunofluorescência , Humanos , Fibrose Pulmonar Idiopática/metabolismo , Fibrose Pulmonar Idiopática/patologia , Técnicas Imunoenzimáticas , Marcação In Situ das Extremidades Cortadas , Integrases , Intubação Intratraqueal , Mesoderma/efeitos dos fármacos , Mesoderma/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , beta-Galactosidase/metabolismo
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