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BACKGROUND & AIMS: Homozygous ZZ alpha-1 antitrypsin (AAT) deficiency produces mutant AAT (Z-AAT) proteins in hepatocytes, leading to progressive liver fibrosis. We evaluated the safety and efficacy of an investigational RNA interference therapeutic, fazirsiran, that degrades Z-AAT messenger RNA, reducing deleterious protein synthesis. METHODS: This ongoing, phase 2 study randomized 40 patients to subcutaneous placebo or fazirsiran 25, 100, or 200 mg. The primary endpoint was percent change in serum Z-AAT concentration from baseline to week 16. Patients with fibrosis on baseline liver biopsy received treatment on day 1, at week 4, and then every 12 weeks and had a second liver biopsy at or after weeks 48, 72, or 96. Patients without fibrosis received 2 doses on day 1 and at week 4. RESULTS: At week 16, least-squares mean percent declines in serum Z-AAT concentration were -61%, -83%, and -94% with fazirsiran 25, 100, and 200 mg, respectively, vs placebo (all P < .0001). Efficacy was sustained through week 52. At postdose liver biopsy, fazirsiran reduced median liver Z-AAT concentration by 93% compared with an increase of 26% with placebo. All fazirsiran-treated patients had histologic reduction from baseline in hepatic globule burden. Portal inflammation improved in 5 of 12 and 0 of 8 patients with a baseline score of >0 in the fazirsiran and placebo groups, respectively. Histologic meta-analysis of histologic data in viral hepatitis score improved by >1 point in 7 of 14 and 3 of 8 patients with fibrosis of >F0 at baseline in the fazirsiran and placebo groups, respectively. No adverse events led to discontinuation, and pulmonary function tests remained stable. CONCLUSIONS: Fazirsiran reduced serum and liver concentrations of Z-AAT in a dose-dependent manner and reduced hepatic globule burden. (ClinicalTrials.gov, Number NCT03945292).
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BACKGROUND: Receptor for Advanced Glycated Endproducts (RAGE) plays a major role in the inflammatory response to infectious and toxin induced acute lung injury. We tested the hypothesis that a RAGE blocking antibody when administered after the onset of injury can reduce lung inflammation compared to control antibody. METHODS: Male and female C57BL/6 (WT) mice were used. Forty-six received lipopolysaccharide (LPS) and 26 PBS by nasal instillation on day one, repeated on day three. On day 2, 36 mice receiving LPS were divided into two groups of 18, one treated with 200 µg of non-immune isotype control IgG and the second group treated with 200 µg of anti-RAGE Ab, each dose divided between IV and IP. Ten of the 46 were not treated. On day 4, before euthanasia, mice were injected with fluorescein isothiocyanate (FITC) labelled albumen. BALF and serum samples were collected as well as lung tissue for immunohistochemistry (IHC). BALF was analyzed for cell (leukocyte) counts, for FITC BALF/serum ratios indicating pulmonary vascular leak, and for cytokines/chemokines using bead based multiplex assays. Quantitative IHC was performed for MPO and RAGE. RESULTS: Ten LPS mice showed minimal inflammation by all measures indicating poor delivery of LPS and were excluded from analysis leaving n = 11 in the LPS + IgG group and n = 12 in the LPS + anti-RAGE group. BALF cell counts were low in the PBS administered mice (4.9 ± 2.1 × 105/ml) and high in the LPS injured untreated mice (109 ± 34) and in the LPS + IgG mice (91 ± 54) while in comparison, LPS + anti-RAGE ab mice counts were significantly lower (51.3 ± 18 vs. LPS + IgG, P = 0.03). The BALF/serum FITC ratios were lower for the LPS + anti-RAGE mice than for the LPS + IgG mice indicating less capillary leakiness. Quantitative IHC RAGE staining was lower in the LPS + anti-RAGE ab mice than in the LPS + IgG treated mice (P = 0.02). CONCLUSIONS: These results describe a four-day LPS protocol to sustain lung injury and allow for treatment and suggests that treatment aimed at blocking RAGE when given after onset of injury can reduce lung inflammation.
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Lesión Pulmonar Aguda , Neumonía , Femenino , Masculino , Animales , Ratones , Lipopolisacáridos/toxicidad , Fluoresceína-5-Isotiocianato/metabolismo , Ratones Endogámicos C57BL , Lesión Pulmonar Aguda/tratamiento farmacológico , Pulmón/metabolismo , Inflamación/metabolismo , Neumonía/inducido químicamente , Neumonía/metabolismo , Inmunoglobulina G/metabolismoRESUMEN
Although allergic asthma is a highly prevalent chronic inflammatory condition, the underlying pathogenesis driving T-helper cell type 2 inflammation is not well understood. Wnt/ß-catenin signaling has been implicated, but the influence of individual members of the pathway is not clear. We hypothesized that SFRP-1 (secreted frizzled-related protein-1), a Wnt signaling modulator, plays an important role in the development of allergic inflammation in asthma. Using an in vivo house dust mite asthma model, SFRP-1-/- mice were sensitized, and their BAL fluid was collected to evaluate airway inflammation. SFRP-1-/- mice exhibited less inflammation with reduced cellular infiltration and concentration of IL-5 in bronchoalveolar lavage fluid compared with wild-type (WT) mice. Similar findings were observed in WT mice treated with SFRP-1 inhibitor, WAY316606. Alveolar macrophages from sensitized SFRP-1-/- mice demonstrated reduced alternative polarization compared with WT, indicating that macrophages could mediate the alteration in inflammation seen in these mice. These findings suggest that SFRP-1 is an important potentiator of asthmatic airway inflammation.
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Asma , Proteínas de la Membrana/metabolismo , Animales , Asma/patología , Líquido del Lavado Bronquioalveolar , Modelos Animales de Enfermedad , Inflamación/metabolismo , Péptidos y Proteínas de Señalización Intracelular , Ratones , PyroglyphidaeRESUMEN
Acute respiratory distress syndrome (ARDS) is characterized by pulmonary edema and poor gas exchange resulting from severe inflammatory lung injury. Neutrophilic infiltration and increased pulmonary vascular permeability are hallmarks of early ARDS and precipitate a self-perpetuating cascade of inflammatory signaling. The biochemical processes initiating these events remain unclear. Typically associated with extracellular matrix degradation, recent data suggest matrix metalloproteinases (MMPs) are regulators of pulmonary inflammation. To demonstrate that inhalation of a broad MMP inhibitor attenuates LPS induced pulmonary inflammation. Nebulized CGS27023AM (CGS) was administered to LPS-injured mice. Pulmonary CGS levels were examined by mass spectroscopy. Inflammatory scoring of hematoxylin-eosin sections, examination of vascular integrity via lung wet/dry and bronchoalveolar lvage/serum FITC-albumin ratios were performed. Cleaved caspase-3 levels were also assessed. Differential cell counts and pulse-chase labeling were utilized to determine the effects of CGS on neutrophil migration. The effects of CGS on human neutrophil migration and viability were examined using Boyden chambers and MTT assays. Nebulization successfully delivered CGS to the lungs. Treatment decreased pulmonary inflammatory scores, edema, and apoptosis in LPS treated animals. Neutrophil chemotaxis was reduced by CGS treatment, with inhalation causing significant reductions in both the total number and newly produced bromodeoxyuridine-positive cells infiltrating the lung. Mechanistic studies on cells isolated from humans demonstrate that CGS-treated neutrophils exhibit decreased chemotaxis. The protective effect observed following treatment with a nonspecific MMP inhibitor indicates that one or more MMPs mediate the development of pulmonary edema and neutrophil infiltration in response to LPS injury. In accordance with this, inhaled MMP inhibitors warrant further study as a potential new therapeutic avenue for treatment of acute lung injury.
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Lesión Pulmonar Aguda/tratamiento farmacológico , Endotoxinas/farmacología , Inhibidores de la Metaloproteinasa de la Matriz/farmacología , Neumonía/tratamiento farmacológico , Lesión Pulmonar Aguda/metabolismo , Humanos , Lipopolisacáridos/farmacología , Infiltración Neutrófila/efectos de los fármacos , Infiltración Neutrófila/fisiología , Neutrófilos/efectos de los fármacos , Neutrófilos/metabolismo , Neumonía/inducido químicamente , Neumonía/metabolismo , Factor de Necrosis Tumoral alfa/metabolismoRESUMEN
Asthma is a chronic inflammatory disease mediated by allergen-specific CD4 T cells that promote lung inflammation through recruitment of cellular effectors into the lung. A subset of lung T cells can persist as tissue-resident memory T cells (TRMs) following infection and allergen induction, although the generation and role of TRM in asthma persistence and pathogenesis remain unclear. In this study, we used a mouse model of chronic exposure to intranasal house dust mite (HDM) extract to dissect how lung TRMs are generated and function in the persistence and pathogenesis of allergic airway disease. We demonstrate that both CD4+ and CD8+ T cells infiltrate into the lung tissue during acute HDM exposure; however, only CD4+ TRMs, and not CD8+ TRMs, persist long term following cessation of HDM administration. Lung CD4+ TRMs are localized around airways and are rapidly reactivated upon allergen re-exposure accompanied by the rapid induction of airway hyperresponsiveness independent of circulating T cells. Lung CD4+ TRM activation to HDM challenge is also accompanied by increased recruitment and activation of dendritic cells in the lungs. Our results indicate that lung CD4+ TRMs can perpetuate allergen-specific sensitization and direct early inflammatory signals that promote rapid lung pathology, suggesting that targeting lung CD4+ TRMs could have therapeutic benefit in alleviating recurrent asthma episodes.
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Alérgenos/inmunología , Asma/inmunología , Linfocitos T CD4-Positivos/inmunología , Pulmón/inmunología , Activación de Linfocitos/inmunología , Animales , Linfocitos T CD8-positivos/inmunología , Modelos Animales de Enfermedad , Femenino , Hipersensibilidad/inmunología , Mediadores de Inflamación/inmunología , Ratones , Ratones Endogámicos C57BL , Neumonía/inmunología , Pyroglyphidae/inmunología , Hipersensibilidad Respiratoria/inmunologíaRESUMEN
BACKGROUND: Expression of the Receptor for Advanced Glycation Endproducts (RAGE) initiates pro-inflammatory pathways resulting in lung destruction. We hypothesized that RAGE directed imaging demonstrates increased lung uptake in smoke-exposure. METHODS: After exposure to room air or to cigarette smoke for 4-weeks or 16-weeks, rabbits were injected with 99mTc-anti-RAGE F(ab')2 and underwent Single-Photon Emission Computed Tomography/Computed Tomography (SPECT/CT) imaging. Lung radiotracer uptake was calculated as percent injected dose (%ID). Lungs were dissected for gamma well counting and histological analysis. RESULTS: 99mTc-anti-RAGE F(ab')2 SPECT/CT imaging demonstrated increased lung expression of RAGE with smoke exposure compared to room air control at 4-weeks: Room air right (R) 0.75 ± 0.38%ID, left (L) 0.62 ± 0.32%ID vs. Smoke exposed R 0.17 ± 0.03, L 0.17 ± 0.02%ID (p = 0.02 and 0.028, respectively). By 16-weeks of smoke exposure, the uptake decreased to 0.19 ± 0.05%ID R and 0.17 ± 0.05%ID L, significantly lower than 4-week imaging (p = 0.0076 and 0.0129 respectively). Staining for RAGE confirmed SPECT results, with the RAGE ligand HMGB1 upregulated in the macrophages of 4-week smoke-exposed rabbits. CONCLUSIONS: RAGE-directed imaging identified pulmonary RAGE expression acutely in vivo in an animal model of emphysema early after smoke exposure, with diminution over time. These studies document the extent and time course of RAGE expression under smoke exposure conditions and could be utilized for disease monitoring and examining response to future RAGE-targeted therapies.
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Modelos Animales de Enfermedad , Pulmón/diagnóstico por imagen , Pulmón/metabolismo , Receptor para Productos Finales de Glicación Avanzada/metabolismo , Tomografía Computarizada por Tomografía Computarizada de Emisión de Fotón Único/métodos , Fumar Tabaco/metabolismo , Animales , Femenino , Conejos , Fumar , Fumar Tabaco/patologíaRESUMEN
Macrophage infiltration is common to both emphysema and atherosclerosis, and cigarette smoke down-regulates the macrophage cholesterol efflux transporter ATP binding cassette (ABC)A1. This decreased cholesterol efflux results in lipid-laden macrophages. We hypothesize that cigarette smoke adversely affects cholesterol transport via an ABCA1-dependent mechanism in macrophages, enhancing TLR4/myeloid differentiation primary response gene 88 (Myd88) signaling and resulting in matrix metalloproteinase (MMP) up-regulation and exacerbation of pulmonary inflammation. ABCA1 is significantly down-regulated in the lung upon smoke exposure conditions. Macrophages exposed to cigarette smoke in vivo and in vitro exhibit impaired cholesterol efflux correlating with significantly decreased ABCA1 expression, up-regulation of the TLR4/Myd88 pathway, and downstream MMP-9 and MMP-13 expression. Treatment with liver X receptor (LXR) agonist restores ABCA1 expression after short-term smoke exposure and attenuates the inflammatory response; after long-term smoke exposure, there is also attenuated physiologic and morphologic changes of emphysema. In vitro, treatment with LXR agonist decreases macrophage inflammatory activation in wild-type but not ABCA1 knockout mice, suggesting an ABCA1-dependent mechanism of action. These studies demonstrate an important association between cigarette smoke exposure and cholesterol-mediated pathways in the macrophage inflammatory response. Modulation of these pathways through manipulation of ABCA1 activity effectively blocks cigarette smoke-induced inflammation and provides a potential novel therapeutic approach for the treatment of chronic obstructive pulmonary disease.-Sonett, J., Goldklang, M., Sklepkiewicz, P., Gerber, A., Trischler, J., Zelonina, T., Westerterp, M., Lemaître, V., Okada, V., D'Armiento, J. A critical role for ABC transporters in persistent lung inflammation in the development of emphysema after smoke exposure.
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The present study tested the hypothesis that maternal smoke exposure results in fetal lung growth retardation due to dysregulation in various signaling pathways, including the Wnt (wingless-related integration site)/ß-catenin pathway. Pregnant female C57BL/6J mice were exposed to cigarette smoke (100-150 mg/m3) or room air, and offspring were humanely killed on 12.5, 14.5, 16.5, and 18.5 d post coitum (dpc). We assessed lung stereology with Cavalieri estimation; apoptosis with proliferating cell nuclear antigen, TUNEL, and caspase assays; and gene expression with quantitative PCR (qPCR) and RNA sequencing on lung epithelium and mesenchyme retrieved by laser capture microdissection. Results demonstrated a significant decrease in body weight and lung volume of smoke-exposed embryos. At 16.5 dpc, the reduction in lung volume was due to loss of lung mesenchymal tissue correlating with a decrease in cell proliferation (n = 10; air: 61.65% vs. smoke: 44.21%, P < 0.05). RNA sequence analysis demonstrated an alteration in the Wnt pathway, and qPCR confirmed an increased expression of secreted frizzled-related protein 1 (sFRP-1) [n = 12; relative quantification (RQ) 1 vs. 2.33, P < 0.05] and down-regulation of Cyclin D1 (n = 7; RQ 1 vs. 0.61, P < 0.05) in mesenchymal tissue. Furthermore, genome expression studies revealed a smoke-induced up-regulation of Rho-GTPase-dependent actin cytoskeletal signaling that can lead to loss of tissue integrity.-Unachukwu, U., Trischler, J., Goldklang, M., Xiao, R., D'Armiento, J. Maternal smoke exposure decreases mesenchymal proliferation and modulates Rho-GTPase-dependent actin cytoskeletal signaling in fetal lungs.
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Actinas/fisiología , Proteínas Activadoras de GTPasa/metabolismo , Regulación del Desarrollo de la Expresión Génica/efectos de los fármacos , Pulmón/embriología , Células Madre Mesenquimatosas/efectos de los fármacos , Humo/efectos adversos , Animales , Apoptosis , Proliferación Celular/efectos de los fármacos , Citoesqueleto , Femenino , Feto/efectos de los fármacos , Proteínas Activadoras de GTPasa/genética , Pulmón/efectos de los fármacos , Pulmón/metabolismo , Células Madre Mesenquimatosas/fisiología , Ratones , Embarazo , Transducción de Señal/efectos de los fármacos , Transducción de Señal/fisiología , Productos de Tabaco , Proteínas Wnt/genética , Proteínas Wnt/metabolismoRESUMEN
OBJECTIVE: We conducted this study to determine the generalizability of information gained from randomized controlled trials in critically ill patients by assessing the incidence of eligibility for each trial. DESIGN: Prospective, observational cohort study. We identified the 15 most highly cited randomized controlled trials in critical care medicine published between 1998 and 2008. We examined the inclusion and exclusion criteria for each randomized controlled trial and then assessed the eligibility of each patient admitted to a study ICU for each randomized controlled trial and calculated rates of potential trial eligibility in the cohort. SETTING: Three ICUs in two academic medical centers in Canada and the United States. PATIENTS: Adults admitted to participating medical or surgical ICU in November 2010 or July 2011. MEASUREMENTS AND MAIN RESULTS: Among the 15 trials, the most common trial inclusion criteria were clinical criteria for sepsis (six trials) or acute respiratory distress syndrome (four trials), use of invasive mechanical ventilation (five trials) or related to ICU type or duration of ICU stay (five trials). Of the 93 patients admitted to a study ICU, 52% of patients (n = 48) did not meet enrollment criteria for any studied randomized controlled trial and 30% (n = 28) were eligible for only one of the 15. Trial ineligibility was mostly due to failure to meet inclusion criteria (87% of screening assessments) rather than meeting specific exclusion criteria (52% of screening assessments). Of the positive screening assessments, 85% occurred on the first day of ICU admission. CONCLUSIONS: Slightly more than half of the patients assessed were not eligible for enrollment in any of 15 major randomized controlled trials in critical care, most often due to the absence of the specific clinical condition of study. The majority of patients who met criteria for a randomized controlled trial did so on the first day of ICU admission.
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Cuidados Críticos/métodos , Selección de Paciente , Ensayos Clínicos Controlados Aleatorios como Asunto/métodos , Cuidados Críticos/estadística & datos numéricos , Determinación de la Elegibilidad , Femenino , Humanos , Unidades de Cuidados Intensivos/estadística & datos numéricos , Tiempo de Internación/estadística & datos numéricos , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Ensayos Clínicos Controlados Aleatorios como Asunto/estadística & datos numéricos , Índice de Severidad de la EnfermedadRESUMEN
Lung morphometry was introduced over 50 years ago to provide quantitative evaluation of the lung structure. The existing parameters, such as mean linear intercept and destructive index, suffer from simplistic data interpretation and a subjective data acquisition process. To overcome these existing shortcomings, parenchymal airspace profiling (PAP) was developed to provide a more detailed and unbiased quantitative method. Following the standard protocols of fixation, embedding, and sectioning, lung micrographs were: (1) marked with nonparenchymal area, preprocessed, and binarized under the researcher's supervision; (2) analyzed with a statistical learning method, Gaussian mixture model, to provide an unbiased categorization of parenchymal airspace compartments, corresponding to a single alveolus, alveolar sac, and ductal/destructive airspace; and (3) further quantified into morphometric parameters, including reference volume, alveolar count, and ductal/destructive fraction (DF) based on stereological principles. PAP was performed on hematoxylin and eosin-stained lung sections from mice and rabbits. Unbiased categorization revealed differences in alveolar size among several mouse strains (NZW/LacJAsunto(s)
Pulmón/patología
, Tejido Parenquimatoso/patología
, Animales
, Recuento de Células
, Masculino
, Ratones Endogámicos AKR
, Ratones Endogámicos C57BL
, Alveolos Pulmonares/patología
, Especificidad de la Especie
RESUMEN
Asthma is a chronic inflammatory disease, which is characterized by activation of CD4(+) T helper 2 cells orchestrating an allergic airway response. Whereas the role of Wnt family members in regulating T cell maintenance and maturation is established, their contribution to T cell activation in allergic asthma is not known. We hypothesized that Wnt10b plays a role in the modulation of the allergic airway response and affects T cell activation and polarization. Using an in vivo house dust mite asthma model, Wnt10b-deficient (Wnt10b(-/-)) mice were allergen-sensitized and inflammation, as well as T cell activation, was studied in vivo and in vitro. Wnt10b(-/-) mice exhibited an augmented inflammatory phenotype with an increase in eosinophils in the bronchoalveolar lavage and IL-4 and IL-13 in the lungs when compared with wild-type mice. In vitro studies confirmed an increased T helper type 2 polarization and increased T cell activation of Wnt10b(-/-) cells. Accordingly, the percentage of naive T cells was elevated by the addition of recombinant Wnt10b protein. Finally, Wnt10b(-/-) mice exhibited an increase in the percentage of effector T cells in the lungs after house dust mite sensitization, which indicated a heightened activation state, measured by an increased percentage of CD69(hi)CD11a(hi) cells. These findings suggest that Wnt10b plays an important role in regulating asthmatic airway inflammation through modification of the T cell response and is a prospective target in the disease process.
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Asma/inmunología , Modelos Animales de Enfermedad , Linfocitos T/inmunología , Proteínas Wnt/fisiología , Animales , Líquido del Lavado Bronquioalveolar , Polaridad Celular , Pulmón/inmunología , Ratones , Ratones Noqueados , Bazo/inmunología , Bazo/patología , Proteínas Wnt/genéticaRESUMEN
Evaluation of lung disease is limited by the inability to visualize ongoing pathological processes. Molecular imaging that targets cellular processes related to disease pathogenesis has the potential to assess disease activity over time to allow intervention before lung destruction. Because apoptosis is a critical component of lung damage in emphysema, a functional imaging approach was taken to determine if targeting apoptosis in a smoke exposure model would allow the quantification of early lung damage in vivo. Rabbits were exposed to cigarette smoke for 4 or 16 weeks and underwent single-photon emission computed tomography/computed tomography scanning using technetium-99m-rhAnnexin V-128. Imaging results were correlated with ex vivo tissue analysis to validate the presence of lung destruction and apoptosis. Lung computed tomography scans of long-term smoke-exposed rabbits exhibit anatomical similarities to human emphysema, with increased lung volumes compared with controls. Morphometry on lung tissue confirmed increased mean linear intercept and destructive index at 16 weeks of smoke exposure and compliance measurements documented physiological changes of emphysema. Tissue and lavage analysis displayed the hallmarks of smoke exposure, including increased tissue cellularity and protease activity. Technetium-99m-rhAnnexin V-128 single-photon emission computed tomography signal was increased after smoke exposure at 4 and 16 weeks, with confirmation of increased apoptosis through terminal deoxynucleotidyl transferase dUTP nick end labeling staining and increased tissue neutral sphingomyelinase activity in the tissue. These studies not only describe a novel emphysema model for use with future therapeutic applications, but, most importantly, also characterize a promising imaging modality that identifies ongoing destructive cellular processes within the lung.
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Apoptosis , Enfisema Pulmonar/diagnóstico por imagen , Enfisema Pulmonar/patología , Tomografía Computarizada por Tomografía Computarizada de Emisión de Fotón Único , Animales , Anexina A5/metabolismo , Adaptabilidad , Modelos Animales de Enfermedad , Femenino , Humanos , Pulmón/diagnóstico por imagen , Pulmón/patología , Pulmón/fisiopatología , Neumonía/complicaciones , Neumonía/diagnóstico por imagen , Neumonía/patología , Neumonía/fisiopatología , Enfisema Pulmonar/complicaciones , Enfisema Pulmonar/fisiopatología , Conejos , Humo , Tecnecio/metabolismo , Factores de TiempoRESUMEN
Large conductance voltage- and calcium-activated potassium (BK) channels are highly expressed in airway smooth muscle (ASM). Utilizing the ovalbumin (OVA) and house dust mite (HDM) models of asthma in C57BL/6 mice, we demonstrate that systemic administration of the BK channel agonist rottlerin (5 µg/g) during the challenge period reduced methacholine-induced airway hyperreactivity (AHR) in OVA- and HDM-sensitized mice (47% decrease in peak airway resistance in OVA-asthma animals, P<0.01; 54% decrease in HDM-asthma animals, P<0.01) with a 35-40% reduction in inflammatory cells and 20-35% reduction in Th2 cytokines in bronchoalveolar lavage fluid. Intravenous rottlerin (5 µg/g) reduced AHR within 5 min in the OVA-asthma mice by 45% (P<0.01). With the use of an ex vivo lung slice technique, rottlerin relaxed acetylcholine-stimulated murine airway lumen area to 87 ± 4% of the precontracted area (P<0.01 vs. DMSO control). Rottlerin increased BK channel activity in human ASM cells (V50 shifted by 73.5±13.5 and 71.8±14.6 mV in control and asthmatic cells, respectively, both P<0.05 as compared with pretreatment) and reduced the frequency of acetylcholine-induced Ca(2+) oscillations in murine ex vivo lung slices. These findings suggest that rottlerin, with both anti-inflammatory and ASM relaxation properties, may have benefit in treating asthma.
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Acetofenonas/uso terapéutico , Antiinflamatorios/uso terapéutico , Asma/tratamiento farmacológico , Benzopiranos/uso terapéutico , Canales de Potasio de Gran Conductancia Activados por el Calcio/agonistas , Acetofenonas/farmacología , Potenciales de Acción , Animales , Antiinflamatorios/farmacología , Antígenos Dermatofagoides/toxicidad , Asma/inducido químicamente , Benzopiranos/farmacología , Señalización del Calcio , Células Cultivadas , Femenino , Humanos , Canales de Potasio de Gran Conductancia Activados por el Calcio/metabolismo , Ratones , Ratones Endogámicos C57BL , Miocitos del Músculo Liso/metabolismo , Miocitos del Músculo Liso/fisiología , Ovalbúmina/toxicidad , Tráquea/efectos de los fármacos , Tráquea/patologíaRESUMEN
Plasminogen activator inhibitor-1 (PAI-1) is increased in the lungs of patients with pulmonary fibrosis, and animal studies have shown that experimental manipulations of PAI-1 levels directly influence the extent of scarring that follows lung injury. PAI-1 has 2 known properties that could potentiate fibrosis, namely an antiprotease activity that inhibits the generation of plasmin, and a vitronectin-binding function that interferes with cell adhesion to this extracellular matrix protein. To determine the relative importance of each PAI-1 function in lung fibrogenesis, we administered mutant PAI-1 proteins that possessed either intact antiprotease or vitronectin-binding activity to bleomycin-injured mice genetically deficient in PAI-1. We found that the vitronectin-binding capacity of PAI-1 was the primary determinant required for its ability to exacerbate lung scarring induced by intratracheal bleomycin administration. The critical role of the vitronectin-binding function of PAI-1 in fibrosis was confirmed in the bleomycin model using mice genetically modified to express the mutant PAI-1 proteins. We conclude that the vitronectin-binding function of PAI-1 is necessary and sufficient in its ability to exacerbate fibrotic processes in the lung.
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Fibrosis Pulmonar/etiología , Fibrosis Pulmonar/metabolismo , Serpina E2/metabolismo , Vitronectina/metabolismo , Animales , Bleomicina/administración & dosificación , Bleomicina/toxicidad , Líquido del Lavado Bronquioalveolar/química , Colágeno/metabolismo , Modelos Animales de Enfermedad , Humanos , Hidroxiprolina/metabolismo , Pulmón/efectos de los fármacos , Pulmón/metabolismo , Pulmón/patología , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Ratones Transgénicos , Proteínas Mutantes/genética , Proteínas Mutantes/metabolismo , Inhibidor 1 de Activador Plasminogénico/genética , Inhibidor 1 de Activador Plasminogénico/metabolismo , Unión Proteica , Fibrosis Pulmonar/patología , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Serpina E2/sangre , Serpina E2/deficiencia , Serpina E2/genética , Vitronectina/sangreRESUMEN
Smokers with airflow obstruction have an increased risk of atherosclerosis, but the relationship between the pathogenesis of these diseases is not well understood. To determine whether hypercholesterolemia alters lung inflammation and emphysema formation, we examined the lung phenotype of two hypercholesterolemic murine models of atherosclerosis at baseline and on a high-fat diet. Airspace enlargement developed in the lungs of apolipoprotein E-deficient (Apoe(-/-)) mice exposed to a Western-type diet for 10 wk. An elevated number of macrophages and lymphocytes accompanied by an increase in matrix metalloproteinase-9 (MMP-9) activity and MMP-12 expression was observed in the lungs of Apoe(-/-) mice on a Western-type diet. In contrast, low-density lipoprotein receptor-deficient (Ldlr(-/-)) mice did not exhibit lung destruction or inflammatory changes. Most importantly, we revealed augmented expression of the downstream targets of the Toll-like receptor (TLR) pathway, interleukin-1 receptor-associated kinase 1, and granulocyte colony-stimulating factor, in the lungs of Apoe(-/-) mice fed with a Western-type diet. In addition, we demonstrated overexpression of MMP-9 in Apoe(-/-) macrophages treated with TLR4 ligand, augmented with the addition of oxidized LDL, suggesting that emphysema in these mice results from the activation of the TLR pathway secondary to known abnormal cholesterol efflux. Our findings indicate that, in Apoe(-/-) mice fed with an atherogenic diet, abnormal cholesterol efflux leads to increased systemic inflammation with subsequent lung damage and emphysema formation.
Asunto(s)
Apolipoproteínas E/deficiencia , Colesterol/metabolismo , Hipercolesterolemia/patología , Enfisema Pulmonar/metabolismo , Enfisema Pulmonar/patología , Transducción de Señal , Receptor Toll-Like 4/metabolismo , Animales , Apolipoproteínas E/genética , Apolipoproteínas E/metabolismo , Transporte Biológico , Células Cultivadas , Dieta Aterogénica , Dieta Alta en Grasa , Femenino , Factor Estimulante de Colonias de Granulocitos/biosíntesis , Hipercolesterolemia/metabolismo , Quinasas Asociadas a Receptores de Interleucina-1/biosíntesis , Lipoproteínas LDL/metabolismo , Pulmón/metabolismo , Pulmón/patología , Linfocitos , Macrófagos , Metaloproteinasa 12 de la Matriz/biosíntesis , Metaloproteinasa 9 de la Matriz/biosíntesis , Ratones , Ratones Endogámicos C57BL , Ratones Transgénicos , Enfermedad Pulmonar Obstructiva Crónica , Enfisema Pulmonar/genética , Enfisema Pulmonar/inmunología , Receptores de LDL/deficiencia , Receptores de LDL/genética , Receptores de LDL/metabolismoRESUMEN
Tuberous sclerosis (TS) is a rare disorder exhibiting multi-systemic benign neoplasms. We hypothesized the origin of TS neoplastic cells derived from the neural crest given the heterogeneous ecto-mesenchymal phenotype of the most common TS neoplasms. To test this hypothesis, we employed Cre-loxP lineage tracing of myelin protein zero (Mpz)-expressing neural crest cells (NCCs) in spontaneously developing renal tumors of Tsc2 +/- /Mpz(Cre)/TdT fl/fl reporter mice. In these mice, ectopic renal tumor onset was detected at 4 months of age increasing in volume by 16 months of age with concomitant increase in the subpopulation of tdTomato+ NCCs from 0% to 6.45% of the total number of renal tumor cells. Our results suggest that Tsc2 +/- mouse renal tumors arise from domiciled proliferative progenitor cell populations of neural crest origin that co-opt tumorigenesis due to mutations in Tsc2 loci. Targeting neural crest antigenic determinants will provide a potential alternative therapeutic approach for TS pathogenesis.
RESUMEN
Alpha-1 Antitrypsin (AAT) is a serum protease inhibitor that regulates increased lung protease production induced by cigarette smoking. Mutations in the Serpina1 gene cause AAT to form hepatoxic polymers, which can lead to reduced availability for the protein's primary function and severe liver disease. An AAT antisense oligonucleotide (ASO) was previously identified to be beneficial for the AATD liver disease by blocking the mutated AAT transcripts. Here we hypothesized that knockdown of AAT aggravates murine lung injury during smoke exposure and acute exacerbations of chronic obstructive pulmonary disease (COPD). C57BL/6J mice were randomly divided into 4 groups each for the smoking and smoke-flu injury models. The ASO and control (No-ASO) were injected subcutaneously starting with smoking or four days prior to influenza infection and then injected weekly at 50 mg/kg body weight. ASO treatment during a 3-month smoke exposure significantly decreased the serum and lung AAT expression, resulting in increased Cela1 expression and elastase activity. However, despite the decrease in AAT, neither the inflammatory cell counts in the bronchoalveolar lavage fluid (BALF) nor the lung structural changes were significantly worsened by ASO treatment. We observed significant differences in inflammation and emphysema due to smoke exposure, but did not observe an ASO treatment effect. Similarly, with the smoke-flu model, differences were only observed between smoke-flu and room air controls, but not as a result of ASO treatment. Off-target effects or compensatory mechanisms may account for this finding. Alternatively, the reduction of AAT with ASO treatment, while sufficient to protect from liver injury, may not be robust enough to lead to lung injury. The results also suggest that previously described AAT ASO treatment for AAT mutation related liver disease may attenuate hepatic injury without being detrimental to the lungs. These potential mechanisms need to be further investigated in order to fully understand the impact of AAT inhibition on protease-antiprotease imbalance in the murine smoke exposure model.