Emphysema extent on computed tomography is a highly specific index in diagnosing persistent airflow limitation: a real-world study in China.

OBJECTIVE: The diagnostic value of emphysema extent in consistent air flow limitation remains controversial. Therefore, we aimed to assess the value of emphysema extent on computed tomography (CT) on the diagnosis of persistent airflow limitation. Furthermore, we developed a diagnostic criterion for further verification. MATERIALS AND METHODS: We retrospectively enrolled patients who underwent chest CT and lung function test. To be specific, 671 patients were enrolled in the derivation group (Group 1.1), while 479 patients were in the internal validation group (Group 1.2). The percentage of lung volume occupied by low attenuation areas (LAA%) and the percentile of the histogram of attenuation values were calculated. RESULTS: In patients with persistent airflow limitation, the LAA% was higher and the percentile of the histogram of attenuation values was lower, compared with patients without persistent airflow limitation. Using LAA% with a threshold of -950 HU >1.4% as the criterion, the sensitivity was 44.3% and 47.2%, and the specificity was 95.2% and 95.7%, in Group 1.1 and Group 1.2, respectively. The specificity was influenced by the coexistence of interstitial lung disease, pneumothorax, and post-surgery, rather than the coexistence of pneumonia, nodule, or mass. Multivariable models were also developed. CONCLUSION: The emphysema extent on CT is a highly specific marker in the diagnosis of persistent airflow limitation.

Angiotensin-(1-7) decreases the expression of collagen I via TGF-ß1/Smad2/3 and subsequently inhibits fibroblast-myofibroblast transition.

Previous studies have shown that the RAS (renin-angiotensin system) might participate in airway remodelling in asthma. As a main component of the RAS, Ang-(1-7) [angiotensin-(1-7)] has been reported in few studies regarding its protective effect on asthma. However, the functional roles and relevant signalling pathways of Ang-(1-7) have not been well illustrated. In the present study, we analysed the effect of Ang-(1-7) on AngII (angiotensin II)-induced HLF (human lung fibroblast)-MF (myofibroblast) transition by detecting Col-I (collagen type I), TGF-ß1 (transforming growth factor-ß1) and α-SMA (α-smooth muscle actin) expression. We explored further the possible signalling pathways involved in HLF-MF transition. Our results showed that Ang-(1-7) could down-regulate the expression of Col-I, α-SMA and TGF-ß1/Smad2/3 (all P<0.05). A significant decrease was found in phosphorylation of PI3K (phosphoinositide 3-kinase), Akt, p38-MAPK (mitogen-activated protein kinase) and JNK (c-Jun N-terminal kinase) signalling pathways during HLF-MF transition (all P<0.05). Our data suggests that Ang-(1-7) decreases the expression of Col-I via TGF-ß1/Smad2/3 and subsequently inhibits HLF-MF transition.

Long-term efficacy and safety of bronchial thermoplasty in patients with moderate-to-severe persistent asthma: a systemic review and meta-analysis.

OBJECTIVE: To evaluate the long-term efficacy and safety of bronchial thermoplasty (BT) in the treatment of patients with moderate-to-severe persistent asthma. METHODS: We therefore performed a systematic literature review of peer-reviewed studies focusing on BT intervention in asthma control published between January 2000 and June 2014. Three randomized controlled studies and extension studies met the inclusion criteria (n = 6). Outcomes assessed after BT included spirometric data, adverse respiratory events, emergency room (ER) visits and hospitalization for respiratory illness. One-year and 5-year follow-up data were defined as V1 and V5, respectively. RESULTS: There were 249 BT-treated subjects in total who had a 1-year follow-up (V1), whereas 216 of them finished a 5-year follow-up (V5). No evidence of significant decline was found in pre-bronchodilator FEV1 (% predicted) (WMD = 0.75; 95% CI: 3.36 to 1.85; p = 0.57), or in post-bronchodilator FEV1 (% predicted) (WMD = 0.62; 95% CI: 3.32 to 2.08; p = 0.65) between V1 and V5. In addition, the frequency of respiratory adverse events was reduced significantly during the follow-up (RR = 3.41, 95% CI: 2.96-3.93, p < 0.00001). The number of ER visits for adverse respiratory events remained unchanged (RR = 1.06, 95% CI: 0.77-1.46, p = 0.71) after BT treatment. There was no statistically significant increase in the incidence of hospitalization for respiratory adverse events (V5 vs. V1, RR = 1.47, 95% CI: 0.69-3.12, p = 0.32). CONCLUSIONS: These data demonstrate long-term benefits of BT with regard to both asthma control and safety for moderate-to-severe asthmatic patients.

Pulmonary function parameters in high-resolution computed tomography phenotypes of chronic obstructive pulmonary disease.

BACKGROUND: Heterogeneity of clinical presentation of chronic obstructive pulmonary disease (COPD) attributes to different pathological basis. High-resolution computed tomography (HRCT) phenotypes of COPD may reflex the pathological basis of COPD indirectly by evaluating the small airway inflammation and emphysema. How the pulmonary function related with different HRCT phenotypes has not been well known. The aim was to explore the features of pulmonary function parameters in the 3 phenotypes. METHODS: Sixty-three stable COPD patients were allocated in 3 groups based on HRCT findings: phenotype A (absence of emphysema, with minimal evidence of emphysema with or without bronchial wall thickening [BWT]), phenotype E (emphysema without BWT) and phenotype M (emphysema with BWT). The pulmonary function testing was also analyzed. RESULTS: The values of forced expiratory volume in 1 second (FEV1)/forced vital capacity (FVC%), FEV1% and maximum expiratory flows (MEF)50% were the highest in phenotype A (P < 0.05), so was residual volume (RV)/total lung capacity (TLC%) in phenotype E (P < 0.05). Those with MEF50/MEF25 ratio >4.0 were more prevalence in phenotype A than in E and M (odds ratio = 2.214; P < 0.05). The occurrences of RV/TLC% >40% were higher in phenotype E than in A and M (odds ratio = 3.906; P < 0.05). Receiver operating characteristic analysis showed that the cutoff value of MEF50/MEF25 ratio for identifying phenotype A was 2.5, with sensitivity 66.7% and specificity 92.9%. The cutoff value of RV/TLC% for identifying phenotype E was 57.4%, with sensitivity 75.0% and specificity 79.1%. CONCLUSIONS: The different features of pulmonary function parameters were found in various HRCT phenotypes; MEF50/MEF25 ratio could imply phenotype A, whereas RV/TLC% may be the indicator of phenotype E.

Correlation between group behavior and quorum sensing in Pseudomonas aeruginosa isolated from patients with hospital-acquired pneumonia.

BACKGROUND: This study investigated the correlation between the expression of the Las and Rhl quorum-sensing (QS) systems and the communal behavior (motility, biofilm formation, and pyocyanin production) of Pseudomonas aeruginosa (P. aeruginosa) isolated from patients with hospital-acquired pneumonia. METHODS: We analyzed 138 P. aeruginosa isolates from 48 patients (30 men and 18 women; age 68.18±15.08 years). P. aeruginosa clinical isolates were assessed for Las and Rhl gene expression and bacterial motility, biofilm formation, and pyocyanin production. RESULTS: P. aeruginosa swimming, twitching, and swarming motility positively correlated with the expression of LasI, LasR, and RhlI (P<0.05) but not with that of RhlR (P>0.05). At all analyzed time points, a significant positive correlation was found between biofilm formation and the expression of LasI, LasR (P<0.01), and RhlI (P<0.05 for day 1, P<0.01 for days 7 and 14), whereas RhlR expression positively correlated with biofilm formation only on day 14 (P<0.05). On days 1 and 7, positive correlation was observed between pyocyanin production and the levels of LasI and RhlI (P<0.05). In bacterial clearance cases, the expression of QS-related genes and the group behavior of the pathogen did not correlate (P>0.05). However, in cases of persistent P. aeruginosa infection, the changes in LasI and LasR gene expression were positively correlated with those in bacterial motility (P<0.05), and the changes in LasI, LasR, RhlI, and RhlR expression showed a significant positive association with those in biofilm formation (P<0.01). CONCLUSIONS: In patients with hospital-acquired pneumonia, the expression of the Las and Rhl QS genes was associated with bacterial motility, biofilm formation, and pyocyanin production, suggesting an involvement of the QS genes in the clearance of pathogenic P. aeruginosa in patients.

Twice daily N-acetylcysteine 600 mg for exacerbations of chronic obstructive pulmonary disease (PANTHEON): a randomised, double-blind placebo-controlled trial.

BACKGROUND: Increased oxidative stress and inflammation has a role in the pathogenesis of chronic obstructive pulmonary disease (COPD). Drugs with antioxidant and anti-inflammatory properties, such as N-acetylcysteine, might provide a useful therapeutic approach for COPD. We aimed to assess whether N-acetylcysteine could reduce the rate of exacerbations in patients with COPD. METHODS: In our prospective, randomised, double-blind, placebo-controlled, parallel-group study, we enrolled patients aged 40-80 years with moderate-to-severe COPD (post-bronchodilator forced expiratory volume in 1 s [FEV1]/forced vital capacity <0·7 and FEV1 of 30-70% of predicted) at 34 hospitals in China. We stratified patients according to use of inhaled corticosteroids (regular use or not) at baseline and randomly allocated them to receive N-acetylcysteine (one 600 mg tablet, twice daily) or matched placebo for 1 year. The primary endpoint was the annual exacerbation rate in patients who received at least one dose of study drug and had at least one assessment visit after randomisation. This study is registered with the Chinese Clinical Trials Registry, ChiCTR-TRC-09000460. FINDINGS: Between June 25, 2009, and Dec 29, 2010, we screened 1297 patients, of whom 1006 were eligible for randomisation (504 to N-acetylcysteine and 502 to placebo). After 1 year, we noted 497 acute exacerbations in 482 patients in the N-acetylcysteine group who received at least one dose and had at least one assessment visit (1·16 exacerbations per patient-year) and 641 acute exacerbations in 482 patients in the placebo group (1·49 exacerbations per patient-year; risk ratio 0·78, 95% CI 0·67-0·90; p=0·0011). N-acetylcysteine was well tolerated: 146 (29%) of 495 patients who received at least one dose of N-acetylcysteine had adverse events (48 serious), as did 130 (26%) of 495 patients who received at least one dose of placebo (46 serious). The most common serious adverse event was acute exacerbation of COPD, occurring in 32 (6%) of 495 patients in the N-acetylcysteine group and 36 (7%) of 495 patients in the placebo group. INTERPRETATION: Our findings show that in Chinese patients with moderate-to-severe COPD, long-term use of N-acetylcysteine 600 mg twice daily can prevent exacerbations, especially in disease of moderate severity. Future studies are needed to explore efficacy in patients with mild COPD (GOLD I). FUNDING: Hainan Zambon Pharmaceutical.

Clinical features of three avian influenza H7N9 virus-infected patients in Shanghai.

INTRODUCTION: Since February 2013, a novel reassortant H7N9 virus associated with human deaths, but no apparent outbreaks in poultry and wild birds has emerged in eastern China. OBJECTIVES: The potential reemergence of H7N9 during next year's influenza season demand a further understanding of this important disease. METHODS: Between March 1 and April 30, 2013, we obtained and analyzed clinical, epidemiologic and radiologic features, and virologic data from three laboratory-confirmed patients of A H7N9 infection admitted in Shanghai Ruijin Hospital. RESULTS: All patients were middle to old aged (mean age 62 years) and overweight (mean body mass index 31) patients. Two patients were exposed to poultry directly or indirectly in food market. They presented with fever and rapidly progressive pneumonia that did not respond to antibiotics. Time between onset of symptoms and onset of respiratory failure (days) were 7-11 days. Two patients presented secondary invasive bacterial infections. All patients died on day 7 to day 86 after the onset of symptoms. CONCLUSIONS: Cross species poultry-to-person transmission of this new reassortant avian influenza H7N9 virus can result in severe and fatal respiratory disease like acute respiratory distress syndrome (ARDS) in humans. Reduplicate chest imaging examination is suggested for risky patients with fever and dyspnea. Secondary invasive bacterial infections and pneumothorax can cause severe and fatal consequence. Old age, obesity and presence of comorbidity may be associated with increased mortality. Pulmonary fibrosis can be seen at late stage of the disease.

Association between the interleukin-13 gene and development of chronic obstructive pulmonary disease in southern Chinese Han population: a case-control study.

BACKGROUND: Interleukin-13 (IL-13) has been implicated to be responsible for recruitment of inflammatory cells from the blood to the lung, regulation of matrix metalloproteinase and induction of mucin production and secretion in chronic obstructive pulmonary disease (COPD). We determined plasma IL-13 levels in patients with COPD and investigated its association with common polymorphisms of IL-13 gene in a case-control study. METHODS: We genotyped 160 cases and 175 control subjects in a local hospital using Mass-Array(TM) Technology Platform then tested the association of four SNPs in IL-13 (rs1295685, rs1800925, rs1881457, rs20541) with COPD, and then determined plasma IL-13 levels in patients with COPD and controls. RESULTS: Association was found between IL-13 gene SNPs (rs20541 and rs1800925) and an increased risk of COPD. By linkage disequilibrium (LD) analysis, two blocks (rs1881457 and rs1800925; rs20541 and rs1295685) were found. The risk of COPD was found associated with the IL-13 gene polymorphism among southern Chinese Han population. Plasma IL-13 level was increased in COPD patients compared with controls. CONCLUSIONS: The polymorphism of the IL-13 gene is associated with an increased risk of COPD in southern Chinese Han population. Plasma IL-13 levels were found elevated in patients with COPD.

CD39/CD73 and the imbalance of Th17 cells and regulatory T cells in allergic asthma.

In the immune system, CD4+CD25+Foxp3+ regulatory T cells (Tregs) maintain self­tolerance and Th17 cells mediate inflammatory responses. CD39 is expressed on the surface of a subset of naturally occurring human Tregs that are important in constraining pathogenic Th17 cells. Additional studies have shown that Tregs differentiate into interleukin­17 (IL­17)+Foxp3+ T cells. Our previous study indicated an imbalance of Th17 and Tregs in allergic asthma; however, the underlying mechanisms remain poorly understood. Using quantitative PCR (qPCR), CD39 and CD73 mRNA levels in CD4+ T cells were investigated. Flow cytometry was used to analyze the proportion of IL­17+Foxp3+ T cells, and CD39 and CD73 expressed by CD4+ T cells and Tregs in the peripheral blood of the subjects. The results of the present study demonstrated an increased frequency of CD4+Foxp3+IL­17+ T cells in moderate to severe asthma. A deficiency in CD39 expressed on the surface of CD4+ T cells and Tregs was observed in asthma patients. The expression of CD39 and CD73 on the surface of CD4+ T cells and Tregs was negatively correlated with the number of Th17 cells. These results indicated that the plasticity of Tregs transforming to IL­17+Foxp3+CD4+ T cells, the reduced frequency of CD39+ Tregs and less effective suppression of IL­17 production by residual CD39+ Tregs leads to an imbalance of Th17 and Tregs in asthma. Therefore, enhanced CD39 activity is hypothesized to prevent the progression of asthma.

An increased ratio of Th2/Treg cells in patients with moderate to severe asthma.

BACKGROUND: Recent studies have shown that T helper type-2 (Th2) cells can induce the apoptosis of CD4+CD25+ Treg cells or resist the immunosuppressive effect of Treg cells. We hypothesize that an imbalance of Th2/Treg is present in patients with allergic asthma. METHODS: Twenty-two patients with mild asthma, 17 patients with moderate to severe asthma, and 20 healthy donors were enrolled. All patients were allergic to house dust mites. The proportion of peripheral blood CD4+CD25+ Treg cells and Th2 cells were determined by flow cytometry. The concentration of interleukin (IL)-10, transforming growth factor (TGF)-ß and IL-4 in plasma was determined by enzyme linked immunosorbent assay. In these subjects, peripheral blood mononuclear cells from 17 mild asthmatic patients, 13 moderate to severe asthmatic patients and 14 healthy donors were acquired and expression of forkhead box P3 (Foxp3) and GATA-3 mRNA was detected by reverse-transcriptase polymerase chain reaction. RESULTS: Compared with healthy donors and patients with mild asthma, the percent of CD4+CD25+ Treg cells and plasma IL-10 levels were decreased in patients with moderate to severe asthma. There were no significant differences in Foxp3 mRNA expression among three groups, but a downward trend seen among patients with asthma. However, the percent of Th2 cells, IL-4 levels and expression of GATA-3 mRNA was markedly higher in patients with mild and moderate to severe asthma than in the control group. The ratio of Th2/Treg and their cytokines was increased in allergic asthma, especially for moderate to severe asthma. The ratio of GATA-3/Foxp3 mRNA was also increased in allergic asthma. In patients with moderate to severe asthma, the percentage of peripheral blood Treg cells was negatively correlated to the percentage of Th2 cells and IL-4 levels. CONCLUSIONS: The decline of CD4+CD25+ Treg cells in patients with moderate to severe asthma may play an important role in progress of the disease. Furthermore, the deficiency of CD4+CD25+ Treg cells was associated with the over-expression of Th2 response.

Whole-exome sequencing to identify novel somatic mutations in squamous cell lung cancers.

Squamous cell lung cancer is a major histotype of non-small cell lung cancer (NSCLC) that is distinct from lung adenocarcinoma. We used whole-exome sequencing to identify novel non-synonymous somatic mutations in squamous cell lung cancer. We identified 101 single-nucleotide variants (SNVs) including 77 non-synonymous SNVs (67 missense and 10 nonsense mutations) and 11 INDELs causing frameshifts. We also found four SNVs located within splicing sites. We verified 62 of the SNVs (51 missense, 10 nonsense and 1 splicing-site mutation) and 10 of the INDELs as somatic mutations in lung cancer tissue. Sixteen of the mutated genes were also mutated in at least one patient with a different type of lung cancer in the Catalogue of Somatic Mutation in Cancer (COSMIC) database. Four genes (LPHN2, TP53, MYH2 and TGM2) were mutated in approximately 10% of the samples in the COSMIC database. We identified two missense mutations in C10orf137 and MS4A3 that also occurred in other solid-tumor tissues in the COSMIC database. We found another somatic mutation in EP300 that was mutated in 4.2% of the 2,020 solid-tumor samples in the COSMIC database. Taken together, our results implicate TP53, EP300, LPHN2, C10orf137, MYH2, TGM2 and MS4A3 as potential driver genes of squamous cell lung cancer.

Angiotensin-converting enzyme 2 attenuates the metastasis of non-small cell lung cancer through inhibition of epithelial-mesenchymal transition.

Angiotensin-converting enzyme 2 (ACE2) is a key enzyme of the renin-angiotensin system (RAS). ACE2 plays a critical counterbalancing role by degrading angiotensin II (Ang II) to Ang 1-7. Recent studies suggest that RAS influences tumor growth and development by its paracrine effects on the tumor microenvironment. Epithelial­mesenchymal transition (EMT) is now thought to be a process that plays a fundamental role in tumor progression and metastasis. In the present study, we investigated the role of ACE2 in lung cancer metastasis and the mechanism of EMT. This is the first study to elucidate the mechanism through which the overexpression of ACE2 in the A549 lung cancer cell line decreases metastasis formation in vivo and upregulates the expression of E-cadherin both in vitro and in vivo. We also observed the downregulation of vimentin, which supports a role of ACE2 in influencing EMT in lung cancer. Further analysis indicated that ACE2 abrogated the upregulation of TGF-ß1-induced EMT markers, such as vimentin and α-smooth muscle actin (αSMA) in vitro in A549 cells. Finally, exposing A549 cells stably expressing ACE2 to DX600, an inhibitor of ACE2, recovered the sensitivity of lung cancer cells to TGF-ß1-mediated induction of EMT. Our study demonstrated that ACE2 attenuated the metastasis of lung cancer and may serve as a target for new strategies to inhibit EMT in cancer cells.

Obstructive sleep apnea is associated with impaired glucose metabolism in Han Chinese subjects.

BACKGROUND: Increasingly, evidence from population, clinic-based and laboratory studies supports an independent association between obstructive sleep apnea syndrome (OSAS) and an increased risk of type 2 diabetes; however, this observation has yet to be replicated in China and the potential mechanisms that link these two conditions are not clear. METHODS: A total of 179 Han Chinese subjects were enrolled in this study. All subjects underwent polysomnography, the oral glucose tolerance-insulin releasing test (OGTT-IRT) and serum HbA(1)c measurement. Indexes including homeostasis model assessment-IR (HOMA-IR), Matsuda index, HOMA-ß, early phase insulinogenic index (ΔI(30)/ΔG(30)), AUC-I(180) and oral disposition index (DIo) were calculated for the assessment of insulin resistance and pancreatic ß-cell function. RESULTS: Based on OGTT, 25.4%, 44.6% and 54.5% subjects were diagnosed having glucose metabolic disorders respectively in control, mild to moderate and severe OSAS groups (P < 0.05). Serum HbA(1)c levels were highest in subjects with severe OSAS (P < 0.05). In contrast, compared with normal subjects, HOMA-ß, ΔI(30)/Δ(G30) and DIO were lower in severe OSAS group (P < 0.05). In stepwise multiple linear regressions, 0-min glucose and HbA(1)c were positively correlated with the percentage of total sleep time below an oxyhemoglobin saturation of 90% (T90) (Beta = 0.215 and 0.368, P < 0.05); 30-min and 60-min glucose was negatively correlated with the lowest SpOO(2) (LSpO(2)) (Beta = -0.214 and -0.241, P < 0.05). HOMA-ß and DI(O) were negatively correlated with T90 (Beta = -0.153 and -0.169, P < 0.05) while body mass index (BMI) was the only determinant of HOMA-IR and Matsuda index. CONCLUSIONS: OSAS is associated with impairment in glucose tolerance and pancreatic ß-cell function in Han Chinese subjects while insulin sensitivity is mainly determined by obesity.

High-dose N-acetylcysteine in the prevention of COPD exacerbations: rationale and design of the PANTHEON Study.

Chronic obstructive pulmonary disease (COPD) is characterized by persistent airflow limitation; from a pathophysiological point of view it involves many components, including mucus hypersecretion, oxidative stress and inflammation. N-acetylcysteine (NAC) is a mucolytic agent with antioxidant and anti-inflammatory properties. Long-term efficacy of NAC 600mg/d in COPD is controversial; a dose-effect relationship has been demonstrated, but at present it is not known whether a higher dose provides clinical benefits. The PANTHEON Study is a prospective, ICS stratified, randomized, double-blind, placebo-controlled, parallel-group, multi-center trial designed to assess the efficacy and safety of high-dose (1200 mg/daily) NAC treatment for one year in moderate-to-severe COPD patients. The primary endpoint is the annual exacerbation rate. Secondary endpoints include recurrent exacerbations hazard ratio, time to first exacerbation, as well as quality of life and pulmonary function. The hypothesis, design and methodology are described and baseline characteristics of recruited patients are presented. 1006 COPD patients (444 treated with maintenance ICS, 562 ICS naive, aged 66.27±8.76 yrs, average post-bronchodilator FEV1 48.95±11.80 of predicted) have been randomized at 34 hospitals in China. Final results of this study will provide objective data on the effects of high-dose (1200 mg/daily) long-term NAC treatment in the prevention of COPD exacerbations and other outcome variables.

Levels of thioredoxin are related to the severity of obstructive sleep apnea: based on oxidative stress concept.

BACKGROUND: Oxidative stress is a typical feature of obstructive sleep apnea (OSA). Thioredoxin (TRX), as one of the oxidative stress biomarkers, is a potent protein disulfide reductase in antioxidant defense. Our study is designed to test whether thioredoxin could assess the severity of OSA. METHODS: Sixty-three adults suspected of having OSA were included in this study and were divided into four groups based on the results of polysomnography (PSG): control, mild, moderate, and severe. Subjects with chronic medical diseases (with the exception of essential hypertension) or taking any antioxidant medication were excluded. Blood samples were obtained within an hour after the overnight PSG test. Plasma TRX levels were detected by enzyme-linked immunosorbent assay. RESULTS: The plasma TRX level in severe group was obviously increased (8.62 ± 2.14, 13.33 ± 5.60, 14.71 ± 5.53, and 16.10 ± 7.34 ng/ml; p < 0.05). The TRX positively related to AHI (r = 0.313; p < 0.05), while negatively related to the lowest O(2) saturation (r = 0.266; p < 0.037). The OSA patients associated with hypertension showed elevated TRX level (17.70 ± 6.98 vs. 13.43 ± 5.83 ng/ml; t = 2.434, p < 0.018). The cutoff value of TRX for identifying OSA was 9.39 ng/ml (sensitivity 91 %, specificity 78 %), and its cutoff value for differentiating moderate-severe OSA from mild OSA was 11.79 ng/ml (sensitivity 75 %, specificity 65 %). CONCLUSION: These results suggest that plasma TRX level is associated with the severity of OSA. Therefore, TRX may be used as a severity indicator of OSA.

[Characteristics of histone deacetylase 9 in peripheral blood of patients with bronchial asthma].

OBJECTIVE: To investigate the expression pattern of histone deacetylase 9 (HDAC9) in peripheral blood of asthmatics and its effect on immune cells (Th2, Th17, Tregs) involved in the pathogenesis of asthma. METHODS: Forty-seven asthmatics from Ruijin Hospital were recruited and assigned to intermittent, mild and moderate-severe groups. Lung function test and Asthma Control Questionnaire were performed to evaluate asthma control and severity. Twenty healthy donors were enrolled as controls. GATA3, IL-4, and HDAC9 mRNA expression levels were measured by SYRB Green Real-time PCR. The cytokine IL-17-mainly produced by Th17 cells and TGF-ß-mainly produced by Treg cells, were measured by ELISA. RESULTS: The GATA3 and IL-4 mRNA expression levels (28.12 ± 7.57 and 743.6 ± 312.8) were up-regulated in asthmatics as compared to the healthy controls [0.56 ± 0.22, 0.7 ± 0.8 (U = 16.00, 37.00, P < 0.01)]. The HDAC9 mRNA expression levels of intermittent, mild and moderate-severe groups were 3.20 ± 0.50, 89.6 ± 18.0, 323.0 ± 65.3, respectively, which were associated with the severity of disease (H = 11.32, P < 0.05). The level of IL-17 in asthmatic group was (83 ± 55) ng/L, which was up-regulated as compared to the healthy control [(34 ± 22) ng/L (U = 153.50, P < 0.01)]. The level of TGF-ß was decreased in the asthmatic groups as compared to the healthy control, but the difference did not reach significance. HDAC9 mRNA expression level was positively correlated with GATA3 mRNA expression level (r = 0.482, P < 0.05), and also with IL-4 mRNA expression (r = 0.432, P < 0.05) and IL-17 (r = 0.538, P < 0.05), but negatively correlated with TGF-ß (r = -0.417, P < 0.05). In patients with moderate-severe asthma, HDAC9 mRNA expression level was negatively correlated with FEV(1)% (r = -0.657, P < 0.05). CONCLUSION: HDAC9 mRNA expression was up-regulated in peripheral blood of asthmatics, which was not only associate with the Th2 master transcriptional factors GATA3, cytokine IL-4 mRNA, Th17 and Treg cell-related cytokines, but also with FEV(1)% in moderate-severe asthma.

Genetic polymorphisms of XPD and CDA and lung cancer risk.

To determine the susceptibility genes of lung cancer, we investigated the frequency distributions of the xeroderma pigmentosum complementary group D (XPD) and cytidine deaminase (CDA) genes in patients. A case-control study was conducted involving lung cancer patients and healthy controls. The genotypic distributions of XPD exon 10 G→A (Asp312Asn) and 23 T→G (Lys751Gln), and CDA 79 A→C (Lys27Gln) and 208 G→A (Ala70Thr), were determined using polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP). The results demonstrated that the XPD Asp312Asn genotype distribution was G/G (82.52%) and A/G (17.48%) in the lung cancer patients, and G/G (82.52%), A/G (16.50%) and A/A (10.98%) in the controls. The genotypes of Lys751Gln were T/T (83.49%) and T/G (16.50%) in the lung cancer patients, and T/T (84.47%) and T/G (15.53%) in the controls. Mutations in the XPD single nucleotide polymorphism loci did not demonstrate a significant difference between the two groups (P>0.05). The risk of lung cancer in individuals with mutations at positions 312 and 751 increased 6.13-fold (P=0.047). The CDA Lys27Gln genotype distribution was A/A (78.65%), A/C (20.39%) and C/C (0.98%) in the lung cancer patients, and A/A (79.61%), A/C (19.42%) and C/C (0.98%) in the controls (P=0.985). The CDA Ala70Thr genotype distribution was G/G (98.06%) and A/G (1.94%) in the controls, while all the genotypes were wild-type in the lung cancer patients. The difference between the lung cancer patients and the controls was not statistically significant (P=0.155). There was also no significant difference in the frequency distribution of XPD or CDA between the different pathological types (P>0.05). Our findings demonstrate that the mutation of XPD codons 312 and 751 increases the risk of lung cancer. By contrast, polymorphisms of CDA appear to have little association with lung cancer.

RNA interference-mediated silencing of SOCS-1 via lentiviral vector promotes apoptosis of alveolar epithelial cells in vitro.

Suppressor of cytokine signaling-1 (SOCS1) is a protein that negatively regulates cytokine and growth factor signaling. However, little is known regarding the precise role it plays in idiopathic pulmonary fibrosis. The aim of the present study was to construct a recombinant lentiviral vector for RNA interference targeting the SOCS1 gene and to detect the expression in human alveolar epithelial cells. A lentiviral vector-mediated RNA interference method was used to establish a SOCS1-negative cell line of alveolar origin (A549). Three pairs of complementary small hairpin RNA (shRNA) oligonucleotides targeting the SOCS1 gene were designed, synthesized and inserted into the pPll3.7 vector. Packaged lentivirus particles were obtained after 48 h, and the supernatant was used to transfect the human alveolar epithelial cell line A549. The expression of the SOCS1 protein was detected by Western blotting. MTT assay was used to detect the cell proliferation of alveolar epithelial cells with SOCS1 knockdown. The recombinant plasmids were confirmed by sequencing. The lentivirus-containing supernatant effectively infected the A549 cell line, and the expression of SOCS1 protein was inhibited, which was confirmed by Western blotting in the target cells. MTT assay indicated the inhibition effect for cell proliferation of A549 cells in the SOCS1-RNA interference group, compared to the control group with no interference-mediated silencing of the SOCS1 gene. A lentiviral vector for RNA interference targeting the SOCS1 gene was successfully constructed, and cell survival tests showed that knockdown of the SOCS1 gene promotes the apoptosis of alveolar cells.

Chronic intermittent hypoxia induces thioredoxin system changes in a gender-specific fashion in mice.

Obstructive sleep apnea (OSA) is an independent risk factor of multisystem injury including liver and cardiovascular system. Chronic intermittent hypoxia (CIH) associated with recurrent apneas in patients with OSA is one of the most important causes of the increased various systems injury and oxidative stress induced by CIH is an important pathogenic mechanism. Reports indicated that females are less susceptible to oxidative stress injury. The goal of this study was to explore if there exists gender deference of thioredoxin system (Trx/Txnip) alterations by CIH and to clarify a clue for studying gender disparity of OSA-related multisystem injury. C57BL/6J mice of each gender were exposed to CIH with a fractional inspired O2 (FiO2) nadir of 5%. The oxidative and antioxidant biomarkers were evaluated, including serum OxLDL level and Trx/Txnip expression of liver tissue. Male mice exposed to CIH exhibited significant increases in serum OxLDL level than that of the male control (73.24 ± 22.43 µg/dL, 45.20 ± 28.53 µg/dL, P = 0.032) but no significant difference in the females. Male mice exposed to CIH also exhibited decreased expression of Trx than the female (0.4460 ± 0.1023 versus 1.0454 ± 0.1777, P = 0.013) and increased expression of Txnip than the female (0.0123 ± 0.0476 versus 0.0065 ± 0.0058, P = 0.022). These data suggest that CIH induces thioredoxin system change in a gender-specific fashion in mice.

Coexistence of Th1/Th2 and Th17/Treg imbalances in patients with allergic asthma.

BACKGROUND: Recent recognition is that Th2 response is insufficient to fully explain the aetiology of asthma. Other CD4(+) T cells subsets might play a role in asthma. We investigated the relative abundance and activities of Th1, Th2, Th17 and CD4(+)CD25(+) Treg cells in patients with allergic asthma. METHODS: Twenty-two patients with mild asthma, 17 patients with moderate to severe asthma and 20 healthy donors were enrolled. All patients were allergic to house dust mites. Plasma total IgE, pulmonary function and Asthma Control Questionnaire were assessed. The proportions of peripheral blood Th1, Th2, Th17 and CD4(+)CD25(+) Treg cells were determined by flow cytometry. The expression of cytokines in plasma and in the culture supernatant of peripheral blood mononuclear cells was determined by enzyme linked, immunosorbent assay. RESULTS: The frequency of blood Th2 cells and IL-4 levels in plasma and culture supernatant of peripheral blood mononuclear cells were increased in all patients with allergic asthma. The frequency of Th17 cells and the plasma and culture supernatant levels of IL-17 were increased, whereas the frequency of CD4(+)CD25(+) Treg cells and plasma IL-10 levels were decreased in patients with moderate to severe asthma. Dermatophagoides pteronyssinus specific IgE levels were positively correlated with the percentage of blood Th2 cells and plasma IL-4 levels. Forced expiratory volume in the first second was negatively correlated with the frequency of Th17 cells and plasma IL-17 levels, and positively correlated with the frequency of Treg cells. However, mean Asthma Control Questionnaire scores were positively correlated with the frequency of Th17 cells and plasma IL-17 levels, and negatively correlated with the frequency of Treg cells. CONCLUSIONS: Imbalances in Th1/Th2 and Th17/Treg were found in patients with allergic asthma. Furthermore, elevated Th17 cell responses, the absence of Tregs and an imbalance in Th17/Treg levels were associated with moderate to severe asthma.