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1.
Wilderness Environ Med ; 28(4): 327-331, 2017 Dec.
Article in English | MEDLINE | ID: mdl-28927548

ABSTRACT

A 48-year-old man developed general fatigue, dyspnea, and fever at an altitude of 1562 m from the morning of the first day of a 3-day hike. Despite pharyngeal discomfort and mild general fatigue, he felt that the symptoms were not sufficient to abandon his plan. He usually required 1.5 hours to reach Tokusawa (6.4 km from the starting point at an altitude of 1500 m), but this time he required 2.5 hours and slept briefly upon arrival at Tokusawa due to extreme fatigue and respiratory discomfort. His symptoms became aggravated, so he presented at a mountain clinic with oxygen saturation at 80% and body temperature of 37.6ºC. He was diagnosed with hypoxemia due to pneumonia and/or other disease(s) and was evacuated to a hospital where a chest computed tomography scan revealed ground glass opacity and infiltrative shadows. He was treated for pneumonia, but another doctor discovered during follow-up that the patient had sprayed 300 mL of a waterproofing aerosol on mountain equipment in a nonventilated, enclosed area of his home on the night before starting out on the hike. Therefore, waterproofing spray was considered to have caused pulmonary damage. Self-reporting or appropriate questionnaires are the only means of identifying this type of injury. The differential diagnosis of pulmonary problems in an outdoor setting should include toxic aerosol exposure from waterproofing spray.


Subject(s)
Lung Injury/diagnosis , Recreation , Aerosols , Diagnosis, Differential , Humans , Japan , Lung Injury/diagnostic imaging , Lung Injury/etiology , Male , Middle Aged
2.
J Immunol ; 197(2): 504-16, 2016 07 15.
Article in English | MEDLINE | ID: mdl-27279371

ABSTRACT

Fibroblastic foci, known to be the leading edge of fibrosis development in idiopathic pulmonary fibrosis (IPF), are composed of fibrogenic myofibroblasts. Autophagy has been implicated in the regulation of myofibroblast differentiation. Insufficient mitophagy, the mitochondria-selective autophagy, results in increased reactive oxygen species, which may modulate cell signaling pathways for myofibroblast differentiation. Therefore, we sought to investigate the regulatory role of mitophagy in myofibroblast differentiation as a part of IPF pathogenesis. Lung fibroblasts were used in in vitro experiments. Immunohistochemical evaluation in IPF lung tissues was performed. PARK2 was examined as a target molecule for mitophagy regulation, and a PARK2 knockout mouse was employed in a bleomycin-induced lung fibrosis model. We demonstrated that PARK2 knockdown-mediated mitophagy inhibition was involved in the mechanism for activation of the platelet-derived growth factor receptor (PDGFR)/PI3K/AKT signaling pathway accompanied by enhanced myofibroblast differentiation and proliferation, which were clearly inhibited by treatment with both antioxidants and AG1296, a PDGFR inhibitor. Mitophagy inhibition-mediated activation of PDGFR signaling was responsible for further autophagy suppression, suggesting the existence of a self-amplifying loop of mitophagy inhibition and PDGFR activation. IPF lung demonstrated reduced PARK2 with concomitantly increased PDGFR phosphorylation. Furthermore, bleomycin-induced lung fibrosis was enhanced in PARK2 knockout mice and subsequently inhibited by AG1296. These findings suggest that insufficient mitophagy-mediated PDGFR/PI3K/AKT activation, which is mainly attributed to reduced PARK2 expression, is a potent underlying mechanism for myofibroblast differentiation and proliferation in fibroblastic foci formation during IPF pathogenesis.


Subject(s)
Idiopathic Pulmonary Fibrosis/pathology , Mitophagy/physiology , Myofibroblasts/pathology , Ubiquitin-Protein Ligases/metabolism , Animals , Blotting, Western , Cell Differentiation/physiology , Fluorescent Antibody Technique , Humans , Idiopathic Pulmonary Fibrosis/metabolism , Immunohistochemistry , In Situ Nick-End Labeling , Mice , Mice, Knockout , Microscopy, Electron, Transmission , Phosphatidylinositol 3-Kinases/metabolism , Proto-Oncogene Proteins c-akt/metabolism , Receptors, Platelet-Derived Growth Factor/metabolism , Signal Transduction/physiology
3.
Infect Dis (Lond) ; 48(11-12): 782-8, 2016.
Article in English | MEDLINE | ID: mdl-27329337

ABSTRACT

BACKGROUND: Community-acquired pneumonia (CAP) has high morbidity and mortality. Unfortunately, the pathogen detection rate using conventional culture methods is relatively low. We compared comprehensive real-time polymerase chain reaction (real-time PCR) analysis of nasopharyngeal swab specimens (NPS) and sputum samples against conventional methods for ability to detect causative pathogens of CAP. METHODS: We prospectively enrolled adult CAP patients, including those with prior antibiotic use, from December 2012 to May 2014. For each patient, causative pathogens were investigated conventionally and by real-time PCR that can identify 6 bacterial and 11 viral pathogens. RESULTS: Patients numbered 92 (mean age, 63 years; 59 male), including 30 (33%) with prior antibiotic use. Considering all patients, identification of causative pathogens by real-time PCR was significantly more frequent than by conventional methods in all patients (72% vs. 57%, p = 0.018). In patients with prior antibiotic use, identification rates also differed significantly (PCR, 77%; conventional, 50%; p = 0.027). Mixed infections were more frequent according to real-time PCR than conventional methods (26% vs. 4%, p < 0.001). By the real-time PCR, Streptococcus pneumoniae was most frequently identified (38%) as a causative pathogen, followed by Haemophilus influenzae (37%) and Mycoplasma pneumoniae (5%). PCR also identified viral pathogens (21%), with sensitivity enhanced by simultaneous examination of both NPS and sputum samples rather than only NPS samples. CONCLUSIONS: Real-time PCR of NPS and sputum samples could better identify bacterial and viral pathogens in CAP than conventional methods, both overall and in patients with prior antibiotic treatment.


Subject(s)
Community-Acquired Infections/diagnosis , Microbiological Techniques/methods , Molecular Diagnostic Techniques/methods , Pneumonia/diagnosis , Real-Time Polymerase Chain Reaction/methods , Adult , Aged , Aged, 80 and over , Bacteria/classification , Bacteria/isolation & purification , Female , Humans , Japan , Male , Middle Aged , Nasopharynx/microbiology , Nasopharynx/virology , Prospective Studies , Sensitivity and Specificity , Sputum/microbiology , Sputum/virology , Viruses/classification , Viruses/isolation & purification
4.
Article in English | MEDLINE | ID: mdl-26451098

ABSTRACT

Respiratory infection is a major cause of exacerbation in chronic obstructive pulmonary disease (COPD). Infectious contributions to exacerbations remain incompletely described. We therefore analyzed respiratory tract samples by comprehensive real-time polymerase chain reaction (PCR) in combination with conventional methods. We evaluated multiple risk factors for prolonged hospitalization to manage COPD exacerbations, including infectious agents. Over 19 months, we prospectively studied 46 patients with 50 COPD exacerbations, collecting nasopharyngeal swab and sputum samples from each. We carried out real-time PCR designed to detect six bacterial species and eleven viruses, together with conventional procedures, including sputum culture. Infectious etiologies of COPD exacerbations were identified in 44 of 50 exacerbations (88%). Infections were viral in 17 of 50 exacerbations (34%). COPD exacerbations caused by Gram-negative bacilli, including enteric and nonfermenting organisms, were significantly associated with prolonged hospitalization for COPD exacerbations. Our results support the use of a combination of real-time PCR and conventional methods for determining both infectious etiologies and risk of extended hospitalization.


Subject(s)
Disease Progression , Pulmonary Disease, Chronic Obstructive/complications , Real-Time Polymerase Chain Reaction/methods , Respiratory Tract Infections/etiology , Respiratory Tract Infections/microbiology , Aged , Aged, 80 and over , Female , Hospitalization , Humans , Male , Middle Aged , Prospective Studies , Risk Factors , Sputum/microbiology
5.
Autophagy ; 11(3): 547-59, 2015.
Article in English | MEDLINE | ID: mdl-25714760

ABSTRACT

Cigarette smoke (CS)-induced mitochondrial damage with increased reactive oxygen species (ROS) production has been implicated in COPD pathogenesis by accelerating senescence. Mitophagy may play a pivotal role for removal of CS-induced damaged mitochondria, and the PINK1 (PTEN-induced putative kinase 1)-PARK2 pathway has been proposed as a crucial mechanism for mitophagic degradation. Therefore, we sought to investigate to determine if PINK1-PARK2-mediated mitophagy is involved in the regulation of CS extract (CSE)-induced cell senescence and in COPD pathogenesis. Mitochondrial damage, ROS production, and cell senescence were evaluated in primary human bronchial epithelial cells (HBEC). Mitophagy was assessed in BEAS-2B cells stably expressing EGFP-LC3B, using confocal microscopy to measure colocalization between TOMM20-stained mitochondria and EGFP-LC3B dots as a representation of autophagosome formation. To elucidate the involvement of PINK1 and PARK2 in mitophagy, knockdown and overexpression experiments were performed. PINK1 and PARK2 protein levels in lungs from patients were evaluated by means of lung homogenate and immunohistochemistry. We demonstrated that CSE-induced mitochondrial damage was accompanied by increased ROS production and HBEC senescence. CSE-induced mitophagy was inhibited by PINK1 and PARK2 knockdown, resulting in enhanced mitochondrial ROS production and cellular senescence in HBEC. Evaluation of protein levels demonstrated decreased PARK2 in COPD lungs compared with non-COPD lungs. These results suggest that PINK1-PARK2 pathway-mediated mitophagy plays a key regulatory role in CSE-induced mitochondrial ROS production and cellular senescence in HBEC. Reduced PARK2 expression levels in COPD lung suggest that insufficient mitophagy is a part of the pathogenic sequence of COPD.


Subject(s)
Cellular Senescence , Epithelial Cells/pathology , Mitophagy , Protein Kinases/physiology , Pulmonary Disease, Chronic Obstructive/physiopathology , Ubiquitin-Protein Ligases/physiology , Adult , Aged , Autophagy , Bronchi/cytology , Female , Humans , Immunohistochemistry , Lung/physiopathology , Male , Microscopy, Electron , Middle Aged , Mitochondria/pathology , Pulmonary Disease, Chronic Obstructive/immunology , Reactive Oxygen Species/metabolism , Smoking/adverse effects , Tobacco Products
6.
Mol Ther ; 23(4): 717-27, 2015 Apr.
Article in English | MEDLINE | ID: mdl-25597412

ABSTRACT

Programmed cell death ligand-1 (PD-L1) has recently gained considerable attention for its role in tumor immune escape. Here, we identify a miR-197/CKS1B/STAT3-mediated PD-L1 network in chemoresistant non-small-cell lung cancer (NSCLC), independent of immunoinhibitory signals. miR-197 is downregulated in platinum-resistant NSCLC specimens, resulting in the promotion of chemoresistance, tumorigenicity, and pulmonary metastasis in vitro and in vivo. Mechanistic investigations reveal that a miR-197-mediated CKS1B/STAT3 axis exerts tumor progression regulated by various oncogenic genes (Bcl-2, c-Myc, and cyclin D1), and PD-L1 is a putative biomarker of this axis. Furthermore, we demonstrate that a miR-197 mimic sensitizes PD-L1(high) drug-resistant cells to chemotherapy. These results indicate that the biological interaction between PD-L1 and chemoresistance occurs through the microRNA regulatory cascade. More importantly, expression levels of miR-197 are inversely correlated with PD-L1 expression (n = 177; P = 0.026) and are associated with worse overall survival (P = 0.015). Our discoveries suggest that the miR-197/CKS1B/STAT3-mediated network can drive tumor PD-L1 expression as a biomarker of this cascade, and miR-197 replacement therapy may be a potential treatment strategy for chemoresistant NSCLC.


Subject(s)
Antineoplastic Agents/therapeutic use , B7-H1 Antigen/metabolism , CDC2-CDC28 Kinases/metabolism , Carcinoma, Non-Small-Cell Lung/drug therapy , Drug Resistance, Neoplasm , Lung Neoplasms/drug therapy , MicroRNAs/metabolism , STAT3 Transcription Factor/metabolism , Carcinoma, Non-Small-Cell Lung/genetics , Carcinoma, Non-Small-Cell Lung/metabolism , Cell Line, Tumor , Humans , Lung Neoplasms/genetics , Lung Neoplasms/metabolism , MicroRNAs/genetics , Survival Analysis
7.
Intern Med ; 53(16): 1835-9, 2014.
Article in English | MEDLINE | ID: mdl-25130121

ABSTRACT

A 63-year-old woman was diagnosed with advanced lung adenocarcinoma complicated by Trousseau's syndrome characterized by non-bacterial thrombotic endocarditis, asymptomatic brain infarction, deep venous thrombosis, and low-grade disseminated intravascular coagulation (DIC). The patient's DIC rapidly became widespread, and multiple micropulmonary embolisms led to severe respiratory failure. She received a blood transfusion and anticoagulant treatment with heparin and recombinant human soluble thrombomodulin, which modestly ameliorated her symptoms, and additional chemotherapy led to tumor shrinkage with concomitant resolution of Trousseau's syndrome. Although there are no established medical approaches for managing Trousseau's syndrome, intensive anticoagulant treatment may be effective for improving the patients' general condition in order for them to be able to undergo subsequent combination chemotherapy.


Subject(s)
Adenocarcinoma/complications , Adenocarcinoma/drug therapy , Anticoagulants/therapeutic use , Disseminated Intravascular Coagulation/complications , Disseminated Intravascular Coagulation/drug therapy , Lung Neoplasms/complications , Lung Neoplasms/drug therapy , Paraneoplastic Syndromes/complications , Paraneoplastic Syndromes/drug therapy , Adenocarcinoma/diagnosis , Adenocarcinoma of Lung , Disseminated Intravascular Coagulation/diagnosis , Female , Heparin/therapeutic use , Humans , Lung Neoplasms/diagnosis , Middle Aged , Paraneoplastic Syndromes/diagnosis , Treatment Outcome , Venous Thrombosis/complications , Venous Thrombosis/diagnosis , Venous Thrombosis/drug therapy
8.
J Immunol ; 192(3): 958-68, 2014 Feb 01.
Article in English | MEDLINE | ID: mdl-24367027

ABSTRACT

Cigarette smoke (CS)-induced cellular senescence has been implicated in the pathogenesis of chronic obstructive pulmonary disease, and SIRT6, a histone deacetylase, antagonizes this senescence, presumably through the attenuation of insulin-like growth factor (IGF)-Akt signaling. Autophagy controls cellular senescence by eliminating damaged cellular components and is negatively regulated by IGF-Akt signaling through the mammalian target of rapamycin (mTOR). SIRT1, a representative sirtuin family, has been demonstrated to activate autophagy, but a role for SIRT6 in autophagy activation has not been shown. Therefore, we sought to investigate the regulatory role for SIRT6 in autophagy activation during CS-induced cellular senescence. SIRT6 expression levels were modulated by cDNA and small interfering RNA transfection in human bronchial epithelial cells (HBECs). Senescence-associated ß-galactosidase staining and Western blotting of p21 were performed to evaluate senescence. We demonstrated that SIRT6 expression levels were decreased in lung homogenates from chronic obstructive pulmonary disease patients, and SIRT6 expression levels correlated significantly with the percentage of forced expiratory volume in 1 s/forced vital capacity. CS extract (CSE) suppressed SIRT6 expression in HBECs. CSE-induced HBEC senescence was inhibited by SIRT6 overexpression, whereas SIRT6 knockdown and mutant SIRT6 (H133Y) without histone deacetylase activity enhanced HBEC senescence. SIRT6 overexpression induced autophagy via attenuation of IGF-Akt-mTOR signaling. Conversely, SIRT6 knockdown and overexpression of a mutant SIRT6 (H133Y) inhibited autophagy. Autophagy inhibition by knockdown of ATG5 and LC3B attenuated the antisenescent effect of SIRT6 overexpression. These results suggest that SIRT6 is involved in CSE-induced HBEC senescence via autophagy regulation, which can be attributed to attenuation of IGF-Akt-mTOR signaling.


Subject(s)
Autophagy/physiology , Bronchi/pathology , Cellular Senescence/physiology , Epithelial Cells/pathology , Insulin-Like Growth Factor I/physiology , Pulmonary Disease, Chronic Obstructive/pathology , Sirtuins/physiology , Smoke/adverse effects , Acetylation , Autophagy-Related Protein 5 , Cells, Cultured , Cellular Senescence/drug effects , Epithelial Cells/metabolism , Forced Expiratory Volume , Gene Expression Regulation/drug effects , Humans , Microtubule-Associated Proteins/physiology , Mutation , Protein Processing, Post-Translational , Proto-Oncogene Proteins c-akt/physiology , Pulmonary Disease, Chronic Obstructive/physiopathology , RNA Interference , RNA, Small Interfering/pharmacology , Signal Transduction/physiology , Sirtuins/antagonists & inhibitors , Sirtuins/genetics , TOR Serine-Threonine Kinases/physiology , Nicotiana , Vital Capacity
9.
Am J Physiol Lung Cell Mol Physiol ; 305(10): L737-46, 2013 Nov 15.
Article in English | MEDLINE | ID: mdl-24056969

ABSTRACT

Mitochondria are dynamic organelles that continuously change their shape through fission and fusion. Disruption of mitochondrial dynamics is involved in disease pathology through excessive reactive oxygen species (ROS) production. Accelerated cellular senescence resulting from cigarette smoke exposure with excessive ROS production has been implicated in the pathogenesis of chronic obstructive pulmonary disease (COPD). Hence, we investigated the involvement of mitochondrial dynamics and ROS production in terms of cigarette smoke extract (CSE)-induced cellular senescence in human bronchial epithelial cells (HBEC). Mitochondrial morphology was examined by electron microscopy and fluorescence microscopy. Senescence-associated ß-galactosidase staining and p21 Western blotting of primary HBEC were performed to evaluate cellular senescence. Mitochondrial-specific superoxide production was measured by MitoSOX staining. Mitochondrial fragmentation was induced by knockdown of mitochondrial fusion proteins (OPA1 or Mitofusins) by small-interfering RNA transfection. N-acetylcysteine and Mito-TEMPO were used as antioxidants. Mitochondria in bronchial epithelial cells were prone to be more fragmented in COPD lung tissues. CSE induced mitochondrial fragmentation and mitochondrial ROS production, which were responsible for acceleration of cellular senescence in HBEC. Mitochondrial fragmentation induced by knockdown of fusion proteins also increased mitochondrial ROS production and percentages of senescent cells. HBEC senescence and mitochondria fragmentation in response to CSE treatment were inhibited in the presence of antioxidants. CSE-induced mitochondrial fragmentation is involved in cellular senescence through the mechanism of mitochondrial ROS production. Hence, disruption of mitochondrial dynamics may be a part of the pathogenic sequence of COPD development.


Subject(s)
Bronchi/pathology , Cellular Senescence/drug effects , Epithelial Cells/pathology , Mitochondria/pathology , Nicotiana/adverse effects , Reactive Oxygen Species/metabolism , Blotting, Western , Bronchi/drug effects , Bronchi/metabolism , Cells, Cultured , Dynamins , Epithelial Cells/drug effects , Epithelial Cells/metabolism , GTP Phosphohydrolases/antagonists & inhibitors , GTP Phosphohydrolases/genetics , GTP Phosphohydrolases/metabolism , Humans , Immunoenzyme Techniques , Membrane Proteins/antagonists & inhibitors , Membrane Proteins/genetics , Membrane Proteins/metabolism , Microscopy, Electron , Microtubule-Associated Proteins/antagonists & inhibitors , Microtubule-Associated Proteins/genetics , Microtubule-Associated Proteins/metabolism , Mitochondria/drug effects , Mitochondria/metabolism , Mitochondrial Proteins/antagonists & inhibitors , Mitochondrial Proteins/genetics , Mitochondrial Proteins/metabolism , RNA, Small Interfering/genetics
10.
Respir Res ; 14: 30, 2013 Mar 05.
Article in English | MEDLINE | ID: mdl-23497247

ABSTRACT

BACKGROUND: Marked accumulation of alveolar macrophages (AM) conferred by apoptosis resistance has been implicated in pathogenesis of chronic obstructive pulmonary disease (COPD). Apoptosis inhibitor of macrophage (AIM), has been shown to be produced by mature tissue macrophages and AIM demonstrates anti-apoptotic property against multiple apoptosis-inducing stimuli. Accordingly, we attempt to determine if AIM is expressed in AM and whether AIM is involved in the regulation of apoptosis in the setting of cigarette smoke extract (CSE) exposure. METHODS: Immunohistochemical evaluations of AIM were performed. Immunostaining was assessed by counting total and positively staining AM numbers in each case (n = 5 in control, n = 5 in non-COPD smoker, n = 5 in COPD). AM were isolated from bronchoalveolar lavage fluid (BALF). The changes of AIM expression levels in response to CSE exposure in AM were evaluated. Knock-down of anti-apoptotic Bcl-xL was mediated by siRNA transfection. U937 monocyte-macrophage cell line was used to explore the anti-apoptotic properties of AIM. RESULTS: The numbers of AM and AIM-positive AM were significantly increased in COPD lungs. AIM expression was demonstrated at both mRNA and protein levels in isolated AM, which was enhanced in response to CSE exposure. AIM significantly increased Bcl-xL expression levels in AM and Bcl-xL was involved in a part of anti-apoptotic mechanisms of AIM in U937 cells in the setting of CSE exposure. CONCLUSIONS: These results suggest that AIM expression in association with cigarette smoking may be involved in accumulation of AM in COPD.


Subject(s)
Apoptosis Regulatory Proteins/biosynthesis , Gene Expression Regulation , Macrophages, Alveolar/metabolism , Pulmonary Disease, Chronic Obstructive/metabolism , Aged , Antigens, CD/biosynthesis , Antigens, CD/genetics , Antigens, Differentiation, T-Lymphocyte/biosynthesis , Antigens, Differentiation, T-Lymphocyte/genetics , Apoptosis Regulatory Proteins/genetics , Bronchoalveolar Lavage Fluid , Cells, Cultured , Female , HEK293 Cells , Humans , Lectins, C-Type/biosynthesis , Lectins, C-Type/genetics , Macrophages, Alveolar/pathology , Male , Middle Aged , Pulmonary Disease, Chronic Obstructive/genetics , Pulmonary Disease, Chronic Obstructive/pathology , U937 Cells
11.
Am J Physiol Lung Cell Mol Physiol ; 304(1): L56-69, 2013 Jan 01.
Article in English | MEDLINE | ID: mdl-23087019

ABSTRACT

Autophagy, a process that helps maintain homeostatic balance between the synthesis, degradation, and recycling of organelles and proteins to meet metabolic demands, plays an important regulatory role in cellular senescence and differentiation. Here we examine the regulatory role of autophagy in idiopathic pulmonary fibrosis (IPF) pathogenesis. We test the hypothesis that epithelial cell senescence and myofibroblast differentiation are consequences of insufficient autophagy. Using biochemical evaluation of in vitro models, we find that autophagy inhibition is sufficient to induce acceleration of epithelial cell senescence and myofibroblast differentiation in lung fibroblasts. Immunohistochemical evaluation of human IPF biospecimens reveals that epithelial cells show increased cellular senescence, and both overlaying epithelial cells and fibroblasts in fibroblastic foci (FF) express both ubiquitinated proteins and p62. These findings suggest that insufficient autophagy is an underlying mechanism of both accelerated cellular senescence and myofibroblast differentiation in a cell-type-specific manner and is a promising clue for understanding the pathogenesis of IPF.


Subject(s)
Autophagy , Idiopathic Pulmonary Fibrosis/physiopathology , Adaptor Proteins, Signal Transducing/biosynthesis , Cell Differentiation/physiology , Cellular Senescence/physiology , Endoplasmic Reticulum Stress/physiology , Epithelial Cells/pathology , Epithelial Cells/physiology , Humans , Myofibroblasts/cytology , Sequestosome-1 Protein , Tunicamycin/pharmacology , Ubiquitin/biosynthesis
12.
Respirol Case Rep ; 1(2): 36-8, 2013 Dec.
Article in English | MEDLINE | ID: mdl-25473538

ABSTRACT

Thymomas are associated with a wide spectrum of autoimmune paraneoplastic diseases. Here we report the case of 31-year-old male with invasive thymoma, myasthenia gravis, polymyositis, and acute fulminant myocarditis that presented with cardiogenic shock requiring intra-aortic balloon pumping and percutaneous cardiopulmonary support. Corticosteroid therapy was effective. To our knowledge, this is the first case of thymoma with acute fulminant cardiomyositis that was successfully treated by assisted circulation and corticosteroids, despite a poor prognosis.

13.
Intern Med ; 51(22): 3155-8, 2012.
Article in English | MEDLINE | ID: mdl-23154723

ABSTRACT

We present a case of organizing pneumonia complicated by pneumothorax in association with cyst formation that developed during corticosteroid treatment. Although it has been reported that the check-valve mechanism is a plausible cause of cyst and pneumothorax formation in patients with organizing pneumonia, the details of the corresponding pathological changes that occur in air-trapping have not been elucidated. A pathological examination of lung specimens obtained with video-assisted thoracoscopic surgery suggested that granulation tissues plugging the bronchiole lumens might be a potential cause of the check-valve mechanism in this case. In this report, we also reviewed eight other cases of organizing pneumonia with pneumothorax or cyst formation.


Subject(s)
Cysts/etiology , Lung Diseases/etiology , Pneumonia/complications , Pneumothorax/etiology , Adrenal Cortex Hormones/adverse effects , Adult , Cysts/diagnosis , Humans , Lung Diseases/diagnosis , Male , Pneumonia/diagnosis , Pneumonia/drug therapy , Pneumothorax/diagnosis , Pneumothorax/surgery , Thoracic Surgery, Video-Assisted , Tomography, X-Ray Computed
14.
Oncoimmunology ; 1(5): 630-641, 2012 Aug 01.
Article in English | MEDLINE | ID: mdl-22934255

ABSTRACT

Tobacco smoke-induced accelerated cell senescence has been implicated in the pathogenesis of chronic obstructive pulmonary disease (COPD). Cell senescence is accompanied by the accumulation of damaged cellular components suggesting that in COPD, inhibition of autophagy may contribute to cell senescence. Here we look at whether autophagy contributes to cigarette smoke extract (CSE) - induced cell senescence of primary human bronchial epithelial cells (HBEC), and further evaluate p62 and ubiquitinated protein levels in lung homogenates from COPD patients. We demonstrate that CSE transiently induces activation of autophagy in HBEC, followed by accelerated cell senescence and concomitant accumulation of p62 and ubiquitinated proteins. Autophagy inhibition further enhanced accumulations of p62 and ubiquitinated proteins, resulting in increased senescence and senescence-associated secretory phenotype (SASP) with interleukin (IL)-8 secretion. Conversely, autophagy activation by Torin1, a mammalian target of rapamycin (mTOR inhibitor), suppressed accumulations of p62 and ubiquitinated proteins and inhibits cell senescence. Despite increased baseline activity, autophagy induction in response to CSE was significantly decreased in HBEC from COPD patients. Increased accumulations of p62 and ubiquitinated proteins were detected in lung homogenates from COPD patients. Insufficient autophagic clearance of damaged proteins, including ubiquitinated proteins, is involved in accelerated cell senescence in COPD, suggesting a novel protective role for autophagy in the tobacco smoke-induced senescence-associated lung disease, COPD.

15.
Am J Respir Cell Mol Biol ; 46(3): 306-12, 2012 Mar.
Article in English | MEDLINE | ID: mdl-21980054

ABSTRACT

Cigarette smoke induces damage to proteins and organelles by oxidative stress, resulting in accelerated epithelial cell senescence in the lung, which is implicated in chronic obstructive pulmonary disease (COPD) pathogenesis. Although the detailed molecular mechanisms are not fully understood, cellular energy status is one of the most crucial determinants for cell senescence. Creatine kinase (CK) is a constitutive enzyme, playing regulatory roles in energy homeostasis of cells. Among two isozymes, brain-type CK (CKB) is the predominant CK in lung tissue. In this study, we investigated the role of CKB in cigarette smoke extract (CSE)-induced cellular senescence in human bronchial epithelial cells (HBECs). Primary HBECs and Beas2B cells were used. Protein carbonylation was evaluated as a marker of oxidative protein damage. Cellular senescence was evaluated by senescence-associated ß-galactosidase staining. CKB inhibition was examined by small interfering RNA and cyclocreatine. Secretion of IL-8, a hallmark of senescence-associated secretary phenotype, was measured by ELISA. CKB expression levels were reduced in HBECs from patients with COPD compared with that of HBECs from nonsmokers. CSE induced carbonylation of CKB and subsequently decreased CKB protein levels, which was reversed by a proteasome inhibitor. CKB inhibition alone induced cell senescence, and further enhanced CSE-induced cell senescence and IL-8 secretion. CSE-induced oxidation of CKB is a trigger for proteasomal degradation. Concomitant loss of enzymatic activity regulating energy homeostasis may lead to the acceleration of bronchial epithelial cell senescence, which is implicated in the pathogenesis of COPD.


Subject(s)
Bronchi/drug effects , Cellular Senescence/drug effects , Creatine Kinase, BB Form/metabolism , Epithelial Cells/drug effects , Smoke/adverse effects , Smoking/adverse effects , Bronchi/enzymology , Bronchi/immunology , Bronchi/pathology , Cells, Cultured , Creatine Kinase, BB Form/antagonists & inhibitors , Creatine Kinase, BB Form/genetics , Cyclin B1/metabolism , Down-Regulation , Enzyme-Linked Immunosorbent Assay , Epithelial Cells/enzymology , Epithelial Cells/immunology , Epithelial Cells/pathology , Humans , Immunohistochemistry , Interleukin-8/metabolism , Oxidative Stress/drug effects , Protease Inhibitors/pharmacology , Proteasome Endopeptidase Complex/metabolism , Proteasome Inhibitors , Protein Carbonylation/drug effects , Protein Kinase Inhibitors/pharmacology , RNA Interference , Signal Transduction/drug effects , Ubiquitination , beta-Galactosidase/metabolism
16.
Intern Med ; 50(20): 2367-9, 2011.
Article in English | MEDLINE | ID: mdl-22001467

ABSTRACT

We encountered a case of limited-disease small cell lung cancer with episodic syncope. The frequency of the syncopal attacks increased with the increase in the tumor size, thus a relationship was suspected to exist between the SCLC and syncope. Syncope was evaluated by history taking, 24-hour ECG monitoring, and coronary angiography. As orthostatic hypotension and cardiac disease could be excluded, we finally diagnosed this case as neurally mediated syncope. Serum tests for anti-Hu and anti-Yo antibodies were negative. A temporary pacemaker was inserted for sick sinus syndrome. This patient showed good response to the chemotherapy. No further syncopal attacks were observed after the second course of chemotherapy. Here, in addition we review four cases of SCLC with episodic syncope. Interestingly, in all cases, the tumor was located in the left hilum in close vicinity of the afferent vagal nerve (C-fibers) and mechano-receptor. Therefore, we thought that the mechanism underlying the syncope was mechano-receptor hypersensitivity.


Subject(s)
Lung Neoplasms/complications , Small Cell Lung Carcinoma/complications , Syncope, Vasovagal/etiology , Humans , Male , Middle Aged
17.
J Immunol ; 187(1): 510-9, 2011 Jul 01.
Article in English | MEDLINE | ID: mdl-21646299

ABSTRACT

TLR3, one of the TLRs involved in the recognition of infectious pathogens for innate and adaptive immunity, primarily recognizes viral-associated dsRNA. Recognition of dsRNA byproducts released from apoptotic and necrotic cells is a recently proposed mechanism for the amplification of toxicity, suggesting a pivotal participation of TLR3 in viral infection, as well as in lung diseases where apoptosis plays a critical role, such as asthma and chronic obstructive pulmonary disease. In addition to metabolic control, insulin signaling was postulated to be protective by inhibiting apoptosis. Therefore, we explored the role of insulin signaling in protecting against TLR3-mediated apoptosis of human bronchial epithelial cells. Significant TLR3-mediated apoptosis was induced by polyinosinic-polycytidylic acid, a dsRNA analog, via caspase-8-dependent mechanisms. However, insulin efficiently inhibited TLR3/polyinosinic-polycytidylic acid-induced human bronchial epithelial cell apoptosis via PI3K/Akt and ERK pathways, at least in part, via upregulation of cellular FLIPs and through protein synthesis-independent mechanisms. These results indicate the significance of TLR3-mediated dsRNA-induced apoptosis in the pathogenesis of apoptosis-driven lung disease and provide evidence for a novel protective role of insulin.


Subject(s)
Apoptosis/immunology , Extracellular Signal-Regulated MAP Kinases/physiology , Insulin/physiology , MAP Kinase Signaling System/immunology , Phosphatidylinositol 3-Kinase/physiology , Proto-Oncogene Proteins c-akt/physiology , Respiratory Mucosa/immunology , Toll-Like Receptor 3/antagonists & inhibitors , Bronchi/enzymology , Bronchi/immunology , Bronchi/pathology , Cells, Cultured , Humans , Respiratory Mucosa/enzymology , Respiratory Mucosa/pathology , Toll-Like Receptor 3/physiology
18.
Am J Physiol Lung Cell Mol Physiol ; 300(3): L391-401, 2011 Mar.
Article in English | MEDLINE | ID: mdl-21224216

ABSTRACT

Reepithelialization of remodeled air spaces with bronchial epithelial cells is a prominent pathological finding in idiopathic pulmonary fibrosis (IPF) and is implicated in IPF pathogenesis. Recent studies suggest that epithelial senescence is a risk factor for development of IPF, indicating such reepithelialization may be influenced by the acceleration of cellular senescence. Among the sirtuin (SIRT) family, SIRT6, a class III histone deacetylase, has been demonstrated to antagonize senescence. We evaluated the senescence of bronchiolization in association with SIRT6 expression in IPF lung. Senescence-associated ß-galactosidase staining and immunohistochemical detection of p21 were performed to evaluate cellular senescence. As a model for transforming growth factor (TGF)-ß-induced senescence of abnormal reepithelialization, we used primary human bronchial epithelial cells (HBEC). The changes of SIRT6, p21, and interleukin (IL)-1ß expression levels in HBEC, as well as type I collagen expression levels in fibroblasts, were evaluated. In IPF lung samples, an increase in markers of senescence and SIRT6 expression was found in the bronchial epithelial cells lining cystically remodeled air spaces. We found that TGF-ß induced senescence in primary HBEC by increasing p21 expression, and, whereas TGF-ß also induced SIRT6, it was not sufficient to inhibit cellular senescence. However, overexpression of SIRT6 efficiently inhibited TGF-ß-induced senescence via proteasomal degradation of p21. TGF-ß-induced senescent HBEC secreted increased amounts of IL-1ß, which was sufficient to induce myofibroblast differentiation in fibroblasts. These findings suggest that accelerated epithelial senescence plays a role in IPF pathogenesis through perpetuating abnormal epithelial-mesenchymal interactions, which can be antagonized by SIRT6.


Subject(s)
Bronchi/pathology , Cellular Senescence/drug effects , Epithelial Cells/metabolism , Epithelial Cells/pathology , Idiopathic Pulmonary Fibrosis/pathology , Sirtuins/metabolism , Transforming Growth Factor beta1/pharmacology , Cell Differentiation/drug effects , Cyclin-Dependent Kinase Inhibitor p21/metabolism , Epithelial Cells/drug effects , Humans , Idiopathic Pulmonary Fibrosis/metabolism , Interleukin-1beta/metabolism , Myofibroblasts/cytology , Myofibroblasts/drug effects , Proteasome Endopeptidase Complex/metabolism , Protein Processing, Post-Translational/drug effects , beta-Galactosidase/metabolism
19.
J Thorac Oncol ; 4(2): 208-13, 2009 Feb.
Article in English | MEDLINE | ID: mdl-19179898

ABSTRACT

INTRODUCTION: Circulating endothelial cells (CECs) increase in cancer patients and play an important role in tumor neovascularization. METHODS: This study was designed to investigate the role of CEC as a marker for predicting the effectiveness of a carboplatin plus paclitaxel based first line chemotherapy in advanced non-small cell lung cancer (NSCLC). RESULTS: The CEC count in 4 ml of peripheral blood before starting chemotherapy (baseline value) was significantly higher in NSCLC patients, ranging from 32 to 4501/4 ml (n = 31, mean +/- SD = 595 +/- 832), than in healthy volunteers (n = 53, 46.2 +/- 86.3). We did not detect a significant correlation between the CEC count and estimated tumor volume. CECs were significantly decreased by chemotherapy as compared with pretreatment values (175.6 +/- 24 and 173.0 +/- 24, day +8, +22, respectively). We investigated the correlation between baseline CEC and the clinical effectiveness of chemotherapy. CEC values are significantly higher in patients with clinical benefit (partial response and stable disease, 516 +/- 458, 870.8 +/- 1215, respectively) than in progressive disease patients (211 +/- 150). Furthermore, a statistically significant decrease in CECs, on day 22, was observed only in patients with partial response. Patients who had a baseline CEC count greater than 400/4 ml showed a longer progression-free survival (>400, 271 days [range: 181-361] versus <400, 34 [range: 81-186], p = 0.019). CONCLUSION: CEC is suggested to be a promising predictive marker of the clinical efficacy of the CBDCA plus paclitaxel regimen in patients with NSCLC.


Subject(s)
Antineoplastic Combined Chemotherapy Protocols/therapeutic use , Carcinoma, Non-Small-Cell Lung/blood , Carcinoma, Non-Small-Cell Lung/drug therapy , Endothelium, Vascular/pathology , Lung Neoplasms/blood , Lung Neoplasms/drug therapy , Neoplastic Cells, Circulating/pathology , Adenocarcinoma/blood , Adenocarcinoma/drug therapy , Adenocarcinoma/secondary , Adult , Aged , Biomarkers, Tumor/blood , Carboplatin/administration & dosage , Carcinoma, Non-Small-Cell Lung/secondary , Carcinoma, Squamous Cell/blood , Carcinoma, Squamous Cell/drug therapy , Carcinoma, Squamous Cell/secondary , Female , Humans , Lung Neoplasms/pathology , Male , Middle Aged , Neoplasm Staging , Paclitaxel/administration & dosage , Prognosis , Survival Rate , Treatment Outcome
20.
Nihon Kokyuki Gakkai Zasshi ; 46(12): 1059-64, 2008 Dec.
Article in Japanese | MEDLINE | ID: mdl-19195212

ABSTRACT

A 64-year-old woman presented skin lesions on her face, upper extremities and finger erythema (heliotropism and Gottron's sign). She had weakness in her lower extremities. She was given a diagnosis of dermatomyositis (DM), because the serum examination showed that a myositis-specific antibody was positive whereas Jo-1 antibody was negative. The findings of chest X-ray and computed tomography showed that she had limited small cell lung cancer, but no interstitial pneumonia. She was treated with standard chemotherapy consisting of cisplatin and etoposide with accelerated hyperfractionation radiotherapy. She showed partial response to the treatment, whereas the skin lesions and muscle weakness deteriorated accompanied with bone marrow suppression due to chemotherapy. Skin and muscle biopsy were performed and pathological findings showed typical perivasculitis infiltrated with lymphocytes in muscle and skin. With the recovery of bone marrow suppression and partial response due to chemotherapy, the skin lesions improved and creatine kinase became normalized. She was given a diagnosis of paraneoplastic DM. Since severe leukocytopenia paralleled the deterioration of DM, the decrease of peripheral white blood cell counts, especially regulatory T cell counts, may be associated with DM activity.


Subject(s)
Antineoplastic Combined Chemotherapy Protocols/administration & dosage , Dermatomyositis/complications , Leukopenia/chemically induced , Lung Neoplasms/drug therapy , Paraneoplastic Syndromes/complications , Small Cell Lung Carcinoma/drug therapy , Antineoplastic Agents, Phytogenic/administration & dosage , Cisplatin/administration & dosage , Etoposide/administration & dosage , Female , Humans , Middle Aged
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