Does the 2017 global initiative for chronic obstructive lung disease revision really improve the assessment of Chinese chronic obstructive pulmonary disease patients? A multicenter prospective study for more than 5 years.

BACKGROUND: The Global Initiative for Chronic Obstructive Lung Disease (GOLD) 2017 proposed a new classification that reclassified many chronic obstructive pulmonary disease (COPD) patients from group D to B. However, there is a paucity of data related to the comparison between reclassified and non-reclassified COPD patients in terms of long-term prognosis. This study aimed to investigate long-term outcomes of them and determine whether the GOLD 2017 revision improved the assessment of COPD patients. METHODS: This observational, multicenter, prospective study recruited outpatients at 12 tertiary hospitals in China from November 2016 to February 2018 and followed them up until February 2022. All enrolled patients were classified into groups A to D based on GOLD 2017, and the subjects in group B included patients reclassified from group D to B (group DB) and those remaining in group B (group BB). Incidence rates and hazard ratios (HRs) were calculated for the exacerbation of COPD and hospitalization in each group. RESULTS: We included and followed up 845 patients. During the first year of follow-up, the GOLD 2017 classification had a better discrimination ability for different risks of COPD exacerbation and hospitalization than GOLD 2013. Group DB was associated with a higher risk of moderate-to-severe exacerbation (HR = 1.88, 95% confidence interval [CI] = 1.37-2.59, P  <0.001) and hospitalization for COPD exacerbation (HR = 2.23, 95% CI = 1.29-3.85, P  = 0.004) than group BB. However, during the last year of follow-up, the differences in the risks of frequent exacerbations and hospitalizations between group DB and BB were not statistically significant (frequent exacerbations: HR = 1.02, 95% CI = 0.51-2.03, P  = 0.955; frequent hospitalizations: HR = 1.66, 95% CI = 0.58-4.78, P  = 0.348). The mortality rates of the two groups were both approximately 9.0% during the entire follow-up period. CONCLUSIONS: The long-term prognosis of patients reclassified into group B and of those remaining in group B was similar, although patients reclassified from group D to group B had worse short-term outcomes. The GOLD 2017 revision could improve the assessment of Chinese COPD patients in terms of long-term prognosis.

MFG-E8 stabilized by deubiquitinase USP14 suppresses cigarette smoke-induced ferroptosis in bronchial epithelial cells.

Milk fat globule epidermal growth factor 8 (MFG-E8) participates in a range of cellular processes, including reducing apoptosis and oxidative stress. However, its protective activity against cigarette smoke-induced ferroptosis in the pathogenesis of the chronic obstructive pulmonary disease (COPD) and the modulation of MFG-E8 remain unclear. Here, we showed that cigarette smoke diminished MFG-E8 protein levels but had no significant effect on its mRNA levels in lung tissues of humans and mice and in two human bronchial epithelial cell lines. MFG-E8 could attenuate ferroptosis induced by cigarette smoke extract (CSE) in vivo and in vitro. We identified ubiquitin-specific protease 14 (USP14) as a deubiquitinase of MFG-E8 in human bronchial epithelial cells. USP14 interacted with, deubiquitinated and stabilized MFG-E8. Furthermore, USP14 inhibited CSE-induced MFG-E8 proteasomal degradation. USP14 expression downregulated by CSE decreased MFG-E8 abundance and further reduced the antiferroptotic effect of MFG-E8. These findings suggest that USP14 is an essential regulator of MFG-E8 through the proteasomal pathway and that the USP14/MFG-E8 axis plays a critical role in regulating CSE-induced ferroptosis of bronchial epithelial cells.

Extracellular Vesicle Derived From Mesenchymal Stem Cells Have Bidirectional Effects on the Development of Lung Cancer.

Mesenchymal stem cell is a kind of pluripotent cells with the ability of self-renewal and multi-directional differentiation, which exist in bone marrow, umbilical cord blood, umbilical cord tissue, placenta tissue, adipose tissue and so on. Extracellular vesicles are membranous lipid vesicles secreted by a variety of cells and widely present in body fluids, which contain proteins, mRNA, microRNA and other substances, and are an important medium of intercellular communication. At present, more and more evidence shows that mesenchymal stem cell-derived extracellular vesicles play an important role in the development of lung cancer. Regulating the levels of proteins, RNAs and other substances in MSC-EVs and then transplanting them into patients may be a new way to alleviate the development of lung cancer. We mainly introduce the role of extracellular vesicles derived from human umbilical cord mesenchymal stem cells, bone marrow mesenchymal stem cells and adipose mesenchymal stem cells in lung cancer, to provide new alternatives for the treatment of lung cancer.

Omalizumab for STAT3 Hyper-IgE Syndromes in Adulthood: A Case Report and Literature Review.

Background: Hyper-immunoglobulin E (IgE) syndromes (HIES) are a group of primary immune deficiencies disorders (PID) characterized by elevated serum IgE, eczema, recurrent skin, or respiratory system infections and may also be accompanied by some connective tissues and skeletal abnormalities. Currently, there is no complete cure or targeted treatment for HIES. Omalizumab is a humanized recombinant monoclonal antibody against IgE, reducing the level of free IgE, inhibiting the binding of IgE to receptors on the surface of effector cells, and reducing the activation of inflammatory cells and the release of multiple inflammatory mediators. However, the effect of omalizumab in treating HIES remains unknown. Herein, we described a case of an AD-HIES patient with chronic airway disease who benefited from omalizumab treatment. Case Presentation: A 28-year-old Chinese woman was admitted for recurrent cough for 7 years, markedly elevated serum IgE level, and recurrent pneumonia caused by multiple pathogens, such as Pneumocystis jirovecii, Cytomegalovirus, Staphylococcus aureus, Aspergillus, and Mycobacterium tuberculosis. She had eczema-dermatitis, skin abscess, slightly traumatic fracture since childhood, and developed asthma and allergic bronchopulmonary aspergillosis (ABPA) lately. Using whole-exome sequencing, the STAT3 (c.1294G>T, p.Val432Leu) missense mutation for the autosomal dominant hyper-IgE syndrome was identified, and omalizumab was prescribed at 300 mg every 2 weeks. The patient responded well with the improvement of respiratory symptoms and lung function tests. The level of serum IgE remained stable on follow-up. Conclusion: Omalizumab treatment proved beneficial in the case of HIES, especially with chronic airway disease, for which therapeutic options are limited. However, larger-scale prospective studies and long-term follow-up are required to establish the efficacy and safety of this therapeutic intervention.

LncRNA-CCAT1/miR-152-3p is involved in CSE-induced inflammation in HBE cells via regulating ERK signaling pathway.

Emerging studies have noted that dysregulated long non-coding RNAs (lncRNAs) are implicated in the pathological processes of chronic obstructive pulmonary disease (COPD). LncRNA colon cancer-associated transcript 1 (CCAT1) plays well-defined roles in the inflammatory progression. The study aims to figure out the effect and regulatory mechanism of CCAT1 in the cigarette smoke induced inflammation in COPD. The results showed that CCAT1 was highly expressed in lung tissues of smokers with COPD compared with never-smokers without COPD. In human bronchial epithelial (HBE) cells, cigarette smoke extract (CSE) treatment led to an increase in CCAT1 expression in a dose- and time- dependent manner. Functional experiments showed that knockdown of CCAT1 amelioratedCSE-inducedinflammation. Mechanistically, CCAT1 directly targeted miR-152-3p, and miR-152-3p overexpression reversed the pro-inflammatory effects of CCAT1 on HBE cells. Subsequently, miR-152-3p was found to regulate ERK signaling pathway. PD98059, an ERK specific inhibitor, reversed miR-152-3p knockdown mediated inflammation in HBE cells. In addition, CCAT1 acted as a sponge for miR-152-3p to positively regulate ERK signaling pathway. Overall, current findings suggest that CCAT1 promoted inflammation by activating ERK signal pathway via sponging miR-152-3p in CSE-treated HBE cells. These results may provide a novel therapeutic target for alleviating cigarette smoke mediated airway inflammation.

Endothelial Microparticles Derived from Primary Pulmonary Microvascular Endothelial Cells Mediate Lung Inflammation in Chronic Obstructive Pulmonary Disease by Transferring microRNA-126.

BACKGROUND: Extracellular vesicles (EVs) are considered to new types of intercellular communication media, and microRNA is one of the most common transferring components of EVs. This study aimed to explore the potential role of endothelial microparticles (EMPs) derived from primary pulmonary microvascular endothelial cells in regulating lung inflammation of chronic obstructive pulmonary disease (COPD) through transferring microRNA-126 (miR-126). METHODS: EMPs generated from primary pulmonary microvascular endothelial cells were isolated by gradient centrifugation and characterized by transmission electron microscopy, flow cytometry and Western blotting. EMPs were treated to in vitro and in vivo COPD models induced by cigarette smoke extract (CSE). miR-126 mimics or inhibitors were transfected into EMPs by calcium chloride. Pathological changes of lung tissue, mRNA and protein levels of inflammation-related factors were measured to explore the effect of EMPs transferring miR-126 on CSE-induced inflammation. RESULTS: Both in vitro and in vivo studies demonstrated that mRNA and protein levels of inflammation-related factors were significantly increased in COPD group, while EMPs could dramatically reverse these increases. In vitro, overexpression of miR-126 in EMPs decreased HMGB1 expression and magnified the decreasing effect of EMPs on inflammation-related factors. CONCLUSION: The present study reveals that EMPs are capable of alleviating lung inflammation and transferring miR-126 can magnify the anti-inflammatory effect of EMPs, which may provide a novel therapeutic alternative for COPD.

Emerging Therapeutic Potential of Mesenchymal Stem Cell-Derived Extracellular Vesicles in Chronic Respiratory Diseases: An Overview of Recent Progress.

Mesenchymal stem cell-derived extracellular vesicles (MSC-EVs) are able to carry genetic and protein goods to mediate the interaction between MSCs and target cells. Recently, more and more researches have focused on the therapeutic role of MSC-EVs in chronic respiratory diseases. In this review, we summarize the cumulative strategies and mechanisms of MSC-EVs in treating chronic respiratory diseases. This review suggests that MSC-EVs may serve as a novel cell-free-based therapy for chronic respiratory diseases, including COPD, asthma, pulmonary fibrosis, and pulmonary arterial hypertension. In current studies of chronic respiratory diseases, umbilical cord and bone marrow are main sources of MSC-EVs, while adipose tissue, lung, and induced pluripotent stem cells are also applied. Isolation methods of MSC-EVs in treating chronic respiratory diseases involve ultracentrifugation, exosome extraction kits and anion-exchange chromatography. Intratracheal delivery and intravenous administration are the most widely used routes of MSC-EVs. MSC-EVs are able to transfer microRNAs and protein to target cells and further magnify the therapeutic effects.

Existence of multiple organ aging in animal model of emphysema induced by cigarette smoke extract.

INTRODUCTION: It is commonly considered that COPD or at least emphysema represents accelerated lung aging induced in part by oxidative damage from cigarette smoke components. However, the issue if there are any aging signs in other organs in patients with COPD or emphysema remains unclear. The aim of this study is to explore whether there is multiple organ aging in the animal model of emphysema induced by cigarette smoke extract (CSE), and to ascertain the possible mechanisms, if any. METHODS: The animal model of emphysema was induced by CSE. Histomorphological changes in lung, heart, liver, kidney and spleen tissues were measured after staining with hematoxylin and eosin (H&E). The concentrations of stem cell factor (SCF), CyclinD1 and superoxide dismutase (SOD) in serum were determined by ELISA kit. The expressions of p16 (INK4a), Sca-1, eNOS proteins and mRNA in lung, heart, liver, kidney and spleen tissues were detected by Western blotting and quantitative reverse transcriptase polymerase chain reaction (qRT-PCR), respectively. Decitabine (Dec) was applied to examine whether it could alter the changes caused by CSE. RESULTS: The histomorphology of lung tissue was significantly changed, while other organs exhibited normal structure and histomorphology. The concentrations of SCF, CyclinD1 and SOD in serum were lower in the CSE group than in the control group. The expression levels of p16(INK4a) protein and mRNA in lung, heart, liver, kidney and spleen tissues were higher in the CSE group than in the control group, while the expression levels of Sca-1 and eNOS proteins and mRNA were lower in the CSE group than in the control group, in the tissues described above. Dec could partly alleviate the damages caused by CSE and the degree of alleviation resulted by Dec varied from organ to organ. CONCLUSIONS: In addition to the aging of the lung tissue in the emphysema animal model induced by CSE, the tissues of the heart, liver, kidney and spleen were also in the progress of aging, but the sensibility and affinity of lung to CSE were higher than those of the other organs. Multiple organ aging may also exist in the animal model of emphysema induced by CSE. DEC can partly alleviate the multiple organ aging caused by CSE.

Roles of Inflammasome in Cigarette Smoke-Related Diseases and Physiopathological Disorders: Mechanisms and Therapeutic Opportunities.

Cigarette smoke damages a wide range of immunological functions, including innate and adaptive immune responses. Emerging literature demonstrates that inflammasome constitutes an essential component in innate immune response. In this review, we focus on the cumulative mechanisms of inflammasome in cigarette smoke-related diseases and physiopathological disorders, and summarize potential therapeutic opportunities targeting inflammasome. This review suggests that inflammasomes (NLRP3, NLRP6, NLRP12 and AIM2) are involved in the pathogenesis of several cigarette smoke-related diseases (including COPD, ALI, atherosclerosis, kidney injury, bladder dysfunction, and oral leukoplakia) and physiopathological disorders (macrophage dysfunction, endothelial barrier dysfunction, podocyte injury, and ubiquitin-mediated proteasomal processing). MyD88/NF-κB, HMGB1, production of ROS, endoplasmic reticulum stress and mitochondrial dysfunction, and Ca2+ influx are potentially involved in cigarette smoke induced-inflammasome activation. Strategies targeting ROS/NLRP3 inflammasome axis are most widely investigated and show potential therapeutic effects.

Lung adenocarcinoma misdiagnosed as IgG4-related lung disease: A case report and literature review. / 误诊为IgG4ç›¸å ³æ€§è‚ºç— çš„è‚ºè ºç™Œ1ä¾‹å¹¶æ–‡çŒ®å¤ä¹ .

IgG4-related disease (IgG4-RD) is a recently recognized disorder characterized by elevated serum IgG4 levels and infiltration of IgG4 positive blood cells in the affected organs. However, other conditions like malignancy as well as connective tissue diseases, may show similar findings. A 56-year-old male patient visited Second Xiangya Hospital, Central South University for recurrent fever and chest pain for more than 1 month. Preliminary tests diagnosed as IgG4-related lung disease (IgG4-RLD). However, the improvement of symptoms was absent after the treatment with methylprednisolone. The patient underwent the second biopsy and the result eventually demonstrated lung adenocarcinoma. The role of IgG4 in the pathogenesis or prognosis for lung adenocarcinoma remains unclear. Therefore, a thorough evaluation of symptoms, test of specific serum markers and eventually pathological confirmation are required to avoid misdiagnosis.

Clinical characteristics of pulmonary alveolar proteinosis. / 肺泡蛋白沉积症的临床特征.

OBJECTIVES: Pulmonary alveolar proteinosis (PAP) is a rare disease with non-specific and various clinical manifestations, often leading to misdiagnosis. This study aims to raise the awareness of this disease via summarizing the clinical characteristics, diagnosis, and therapy of PAP. METHODS: We retrospectively analyzed clinical data of 25 hospitalized cases of PAP during 2008 and 2019 in the Department of Respiratory and Critical Care Medicine of the Second Xiangya Hospital of Central South University. RESULTS: Cough with unkown reason and dyspnea were common clinical manifastations of PAP. Five patients had a history of occupational inhalational exposure. Sixteen patients had typical image features including ground-glass opacification of alveolar spaces and thickening of the interlobular and intralobular septa, in typical shapes called crazy-paving and geographic pattern. Fourteen patients underwent pulmonary function tests, revealing a reduction in the diffusing capacity for carbon monoxide. The positive rate of transbronchial biopsy was 95%. Five patients received the whole lung lavage and the symptoms and imaging fcauters significantly relieved after five-years follow-up. CONCLUSIONS: PAP is characterized by radiographic pattern and pathology. Transbronchial lung biopsy is effective to make diagnosis of PAP. The whole lung lavage remains a efficient therapy.

Resveratrol attenuates cigarette smoke induced endothelial apoptosis by activating Notch1 signaling mediated autophagy.

BACKGROUND: Increasing evidence shows that endothelial apoptosis contributes to cigarette smoke (CS)-induced disease progression, such as chronic obstructive pulmonary disease (COPD). Our previous studies have validated Notch1 as an anti-apoptotic signaling in CS-induced endothelial apoptosis. Resveratrol (RESV) is a naturally occurring polyphenol that exhibits an anti-apoptotic activity in endothelial cells that exposed to many kinds of destructive stimulus. However, the effects of resveratrol on Notch1 signaling in CS-induced endothelial apoptosis have not yet been fully elucidated. Therefore, the aim of this study was to examine whether RESV can protect endothelial cells from CS-induced apoptosis via regulating Notch1 signaling. METHODS: Human umbilical vein endothelial cells (HUVECs) were pretreated with RESV for 2 h, followed by cotreatment with 2.5%CSE for 24 h to explore the role of RESV in CSE induced endothelial apoptosis. 3-methyladenine (3-MA) or rapamycin was used to alter autophagic levels. Lentivirus Notch1 intracellular domain (LV-N1ICD), γ-secretase inhibitor (DAPT) and Notch1 siRNA were used to change Notch1 expression. The expression of Notch1, autophagic and apoptotic markers were examined by Western blot and the apoptosis rate was detected by Flow cytometry analysis. RESULTS: Our results showed that activating autophagy reduced CSE-induced endothelial apoptosis, while blocking autophagy promoted cell apoptosis in HUVECs. RESV pretreatment attenuated the CSE-induced endothelial apoptosis and activated Notch1 signaling. RESV pretreatment also increased LC3b-II and Beclin1 production, decreased p62 and mTOR expression. 3-MA treatment inhibited autophagy and aggravated CSE induced apoptosis, while rapamycin promoted autophagy, led to a decrease in cell apoptosis. LV-N1ICD transfection upregulated autophagy and reduced apoptosis. However, this protective effect was abolished by 3-MA treatment. In cells treated with DAPT or Notch1 siRNA, autophagy was decreased, while apoptosis was increased. RESV partly rescued the DAPT or Notch1 siRNA induced apoptosis by activating Notch1 signaling. CONCLUSION: In HUVECs, RESV attenuates CSE induced endothelial apoptosis by inducing autophagy in a Notch1-dependent manner.

The clinical characteristics of East Asian patients with Birt-Hogg-Dubé syndrome.

BACKGROUND: Birt-Hogg-Dube (BHD) syndrome is an autosomal dominant disease that has been characterized by skin lesions, multiple pulmonary cysts, spontaneous pneumothorax, and renal tumors, but the patients in Asian countries may show fewer symptoms. We aimed to explore and summarize the clinical features of BHD patients in East Asia to facilitate early diagnosis and timely interventions. METHODS: We collected and analyzed the clinical data of patients diagnosed with BHD in our hospital by reviewing medical records. We performed a systematic literature search regarding the presenting clinical features in BHD patients from China, Japan, and Korea and then reviewed the publications that were identified. RESULTS: In our hospital, 10 patients were diagnosed with BHD from April 2015 to September 2019. After reviewing the literature, we recruited 38 articles, including 12, 20, and 6 reports from China, Japan, and Korea, respectively. A total of 166 patients were included in this study, and 100 of them (60.2%) were females. Multiple pulmonary cysts were present in 145 patients (87.3%), and 124 patients (74.7%) had a history of pneumothorax on at least one occasion. Skin biopsy confirmed fibrofolliculomas (FFs) alone in 22 patients (13.3%), trichodiscomas (TDs) alone in 3 patients (1.8%), and both FFs and TDs in 7 patients (4.2%). Renal carcinoma only occurred in 12 (7.2%) patients. The most frequent genetic mutations in East Asian patients were c.1285delC on exon 11 (18.4%), c.1285dupC on exon 11 (18.4%), and c.1347_1353dupCCACCCT on exon 12 (8.2%). CONCLUSIONS: Our findings suggested that pulmonary cysts are the most frequent radiological findings, and pneumothorax is the most common symptom in East Asian patients with BHD, and that skin lesions and kidney involvement are less frequent. To make an early diagnosis and minimize the severity of complications, careful observation, and timely genetic examination of the FLCN gene is essential.

Blood and Bronchoalveolar Lavage Fluid Metagenomic Next-Generation Sequencing in Pneumonia.

BACKGROUND: Metagenomic next-generation sequencing (mNGS) has made a revolution in the mode of pathogen identification. We decided to explore the diagnostic value of blood and bronchoalveolar lavage fluid (BALF) as mNGS samples in pneumonia. METHODS: We retrospectively reviewed 467 mNGS results and assessed the diagnostic performance of paired blood and BALF mNGS in 39 patients with pneumonia. RESULTS: For bacteria and fungi, 16 patients had culture-confirmed pathogen diagnosis, while 13 patients were culture-negative. BALF mNGS was more sensitive than blood mNGS (81.3% vs. 25.0%, p=0.003), and the specificity in BALF and blood mNGS was not statistically significant different (76.9% vs. 84.6%, p=0.317). For 10 patients without culture test, treatments were changed in 2 patients. For viruses, Epstein-Barr virus was positive in blood mNGS in 9 patients. Human adenovirus was detected in both BALF and blood mNGS in 3 patients. CONCLUSION: Our study suggests that BALF mNGS is more sensitive than blood mNGS in detecting bacteria and fungi, but blood also has advantages to identify the pathogens of pneumonia, especially for some viruses.

The Genomic Characteristics of ALK Fusion Positive Tumors in Chinese NSCLC Patients.

Anaplastic lymphoma kinase (ALK) fusion events account for ~3-7% genetic alterations in patients with non-small cell lung cancer (NSCLC). In this study, we identified the ALK fusion patterns and a novel ALK fusion partner in 44 ALK positive NSCLC patients using a customized HapOncoCDx panel, and identified ALK fusion partners. The most common partner is EML4, forming the variant 1 (v1, E13:A20, 18/44), variant 2 (v2, E20:A20, 5/44), and variant 3 (v3, E6:A20, 13/44). Moreover, we detected a new ALK fusion partner HMBOX1. At the mutation level, TP53 is the most frequently mutated gene (24%), followed by ALK (12%) and STED2 (12%). The median tumor mutation burden (TMB) of these samples is 2.29 mutations/Mb, ranging from 0.76 mut/Mb to 16.79 muts/Mb. We further elaborately portrayed the TP53 mutation sites on the peptide sequence of the encoded protein by lollipop. The mutational signature and copy number alterations (CNAs) of the samples were also analyzed. The CNA events were found in 13 (13/44) patients, and the most commonly amplified genes were MDM2 (n = 4/13) and TERT (n = 4/13). Together, these results may guide personalized clinical management of patients with ALK fusion in the era of precision medicine.

Primary enteric adenocarcinoma: A case report and literature review. / åŽŸå‘æ€§è‚ºè‚ åž‹è ºç™Œ1ä¾‹å¹¶æ–‡çŒ®å¤ä¹ .

Primary enteric adenocarcinoma is a rare variant of primary pulmonary adenocarcinoma. This disease lacks a distinctive manifestation and often requires pathological examination to make a definite diagnosis. A male patient visited the Second Xiangya Hospital, Central South University for consistent cough and sputum production for about 1 year. Anti-infection therapy was given but it showed ineffectiveness. Enteric adenocarcinoma was diagnosed after percutaneous lung biopsy according to pathological findings. Combining this case with relevant literature, we summarized the characteristics to raise physicians' awareness for this rare subtype.

Notch1 regulates endothelial apoptosis via the ERK pathway in chronic obstructive pulmonary disease.

The Notch signaling pathway plays critical role for determining cell fate by controlling proliferation, differentiation, and apoptosis. In the current study, we investigated the roles of the Notch signaling pathway in cigarette smoke (CS)-induced endothelial apoptosis in chronic obstructive pulmonary disease (COPD). We obtained surgical specimens from 10 patients with COPD and 10 control participants. Notch1, 2, and 4 express in endothelial cells, whereas Notch3 mainly localizes in smooth muscle cells. Compared with control groups, we found that the expression of Notch1, 3, and 4 decreased, as well as their target genes Hes1 and Hes2, while the expression of Notch2 and extracellular signal-regulated kinase (ERK)1/2 increased in COPD patients compared with controls, as well as in human pulmonary microvascular endothelial cells (HPMECs) when exposed to CS extract (CSE). Overexpression of Notch1 with N1ICD in HPMECs markedly alleviated the cell apoptosis induced by CSE. The ERK signaling pathway was significantly activated by CSE, which correlated with CSE-induced apoptosis. However, this activation can be abolished by N1ICD overexpression. Furthermore, treatment of PD98059 (ERK inhibitor) significantly alleviated CSE-induced apoptosis, as well as reduced the methylation of mitochondrial transcription factor A (mtTFA) promoter, which was correlated with CS-induced endothelial apoptosis. These results suggest that CS alters Notch signaling in pulmonary endothelial cells. Notch1 protects against CS-induced endothelial apoptosis in COPD through inhibiting the ERK pathway, while the ERK pathway further regulates the methylation of mtTFA promotor.

miR-34a is involved in CSE-induced apoptosis of human pulmonary microvascular endothelial cells by targeting Notch-1 receptor protein.

BACKGROUND: Abnormal apoptosis of lung endothelial cells has been observed in emphysematous lung tissue and has been suggested to be an important upstream event in the pathogenesis of chronic obstructive pulmonary disease (COPD). Studies have shown that microRNAs (miRNAs) contribute to the pathogenesis of pulmonary diseases by regulating cell apoptosis. The present study was designed to investigate the expression of microRNA-34a (miR-34a) in human pulmonary microvascular endothelial cells (HPMECs) exposed to cigarette smoke extract (CSE), and the potential regulatory role of miR-34a in endothelial cell apoptosis. RESULTS: Our results showed that the expression of miR-34a was significantly increased in CSE-treated HPMECs, and inhibiting miR-34a attenuated CSE-induced HPMEC apoptosis. Furthermore, expression of Notch-1, a receptor protein in the Notch signalling pathway, was decreased and was inversely correlated with miR-34a expression in HPMECs treated with CSE. Computational miRNA target prediction confirmed that Notch-1 is a target of miR-34a. Luciferase reporter assay further confirmed the direct interaction between miR-34a and the 3'-untranslated region (UTR) of Notch-1. Restoration of Notch-1 pathway was able to partially block the effect of miR-34a on HPMEC apoptosis. These results indicate that Notch-1 is a critical downstream target of miR-34a in regulating the CSE-induced HPMEC apoptosis. CONCLUSIONS: Our results suggest that miR-34a plays a key role in CSE-induced endothelial cell apoptosis by directly regulating its target gene Notch-1 in endothelial cells.

The role of cyclooxygenase-2 in the protection against apoptosis in vascular endothelial cells induced by cigarette smoking.

BACKGROUND: Apoptosis has been demonstrated to be an important upstream event in the pathogenesis of chronic obstructive pulmonary disease (COPD). Cyclooxygenase-2 (COX-2) seems to be biologically relevant in COPD. However, the role of COX-2 in the apoptosis in vascular endothelial cells induced by cigarette smoke extract (CSE) remains to be elucidated. Our recent study found that the prostacyclin, one of the COX products in the microvascular endothelium, inhibited apoptosis in the emphysematous lungs of rats induced by CSE. In order to clarify the role of COX-2 in the apoptosis of vascular endothelial cells induced by CSE, we performed the present experiment to elucidate it. METHODS: Twenty surgical lung specimens were obtained from 6 patients with COPD, 7 smoking controls and seven nonsmoking controls. The apoptotic index (AI) and COX-2 protein expression were detected in lung tissues. To further investigate the effects of CSE on the apoptosis and COX-2 expression in a human vascular endothelial cell line, the apoptosis rate and COX-2 expression were examined in human umbilical vein endothelial cells (ECV304) under exposure to varied concentrations of CSE as well as under exposure to 5.0% CSE for varied durations. Repeatedly, the apoptosis rate and COX-2 expression in ECV304 cells under 5.0% CSE were examined after exposing to varied concentrations of celecoxib, a highly selective COX-2 inhibitor. RESULTS: Significantly increased AI and expression of COX-2 were found both in the lungs of patients with COPD and smoking controls compared with nonsmoking controls. The CSE induced apoptosis in ECV304 cells in means of both dose-dependent and time-dependent manners. The COX-2 was slightly expressed in the cells after exposing to 5% CSE for 3 and 6 h, and markedly expressed after the exposure time for 9 and 12 h, but vanished after 24 h of the exposure. Of interest, with the completely block of the COX-2 expression by celecoxib at 50.0 µmol/L, the apoptosis rate was markedly increased again in ECV304 cells under exposure to 5.0% CSE. CONCLUSIONS: Endothelial cell apoptosis and the expression of COX-2 protein were increased in both COPD patients and CSE-induced vascular endothelial cells. Of interest, it seems that the COX-2 probably had a protective role against the apoptosis in the vascular endothelial cells induced by cigarette smoking.

Pneumocystis jirovecii dihydropteroate synthase gene mutations in a group of HIV-negative immunocompromised patients with Pneumocystis pneumonia.

The purpose of this study was to investigate dihydropteroate synthase (DHPS) mutations and their clinical context in non-HIV-infected patients with Pneumocystis pneumonia (PCP). DHPS genes in respiratory samples collected from HIV-negative patients with PCP presented between January 2008 and April 2011 were amplified by polymerase chain reaction (PCR) and sequenced. Basic clinical data from the medical records of the patients were also reviewed. The most common point mutations, which result in Thr55Ala and Pro57Ser amino acid substitutions, were not detected in the Pneumocystis jirovecii sampled from the HIV-negative patients. Two other point mutations, which result in nonsynonymous mutation, Asp90Asn and Glu98Lys, were identified in P. jirovecii from two patients. Among the patients, the levels of lactate dehydrogenase (LDH), C-reactive protein (CRP) and plasma (1-3) ß-D-glucan were elevated in 75, 92.31 and 42.86% of patients, respectively. The percentage of circulating lymphocytes was significantly lower in non-survivors than in survivors [4.2%, interquartile range (IQR) 2.4-5.85 versus 10.1%, IQR 5.65-23.4; P=0.019]. The neutrophil proportion in bronchoalveolar lavage fluid (BALF) was significantly higher in non-survivors than in survivors (49.78±27.67 versus 21.33±15.03%; P=0.047). Thirteen patients had received adjunctive corticosteroids (1 mg/kg/day prednisone equivalent) and nine (69.23%) of them eventually experienced treatment failure. No common DHPS gene mutations of P. jirovecii were detected in the HIV-negative PCP patients. However, other mutations did exist, the significance of which remains to be further identified. The elevation of neutrophil counts in BALF and reduction of the number of lymphocytes in peripheral blood may be associated with poor outcome. The efficacy of adjunctive steroid therapy in HIV-negative patients with P. jirovecii infection requires further investigation.