Melatonin improves influenza virus infection-induced acute exacerbation of COPD by suppressing macrophage M1 polarization and apoptosis

BACKGROUND

Influenza A viruses (IAV) are extremely common respiratory viruses for the acute exacerbation of chronic obstructive pulmonary disease (AECOPD), in which IAV infection may further evoke abnormal macrophage polarization, amplify cytokine storms. Melatonin exerts potential effects of anti-inflammation and anti-IAV infection, while its effects on IAV infection-induced AECOPD are poorly understood.

METHODS

COPD mice models were established through cigarette smoke exposure for consecutive 24 weeks, evaluated by the detection of lung function. AECOPD mice models were established through the intratracheal atomization of influenza A/H3N2 stocks in COPD mice, and were injected intraperitoneally with melatonin (Mel). Then, The polarization of alveolar macrophages (AMs) was assayed by flow cytometry of bronchoalveolar lavage (BAL) cells. In vitro, the effects of melatonin on macrophage polarization were analyzed in IAV-infected Cigarette smoking extract (CSE)-stimulated Raw264.7 macrophages. Moreover, the roles of the melatonin receptors (MTs) in regulating macrophage polarization and apoptosis were determined using MTs antagonist luzindole.

RESULTS

The present results demonstrated that IAV/H3N2 infection deteriorated lung function (reduced FEV20,50/FVC), exacerbated lung damages in COPD mice with higher dual polarization of AMs. Melatonin therapy improved airflow limitation and lung damages of AECOPD mice by decreasing IAV nucleoprotein (IAV-NP) protein levels and the M1 polarization of pulmonary macrophages. Furthermore, in CSE-stimulated Raw264.7 cells, IAV infection further promoted the dual polarization of macrophages accompanied with decreased MT1 expression. Melatonin decreased STAT1 phosphorylation, the levels of M1 markers and IAV-NP via MTs reflected by the addition of luzindole. Recombinant IL-1β attenuated the inhibitory effects of melatonin on IAV infection and STAT1-driven M1 polarization, while its converting enzyme inhibitor VX765 potentiated the inhibitory effects of melatonin on them. Moreover, melatonin inhibited IAV infection-induced apoptosis by suppressing IL-1β/STAT1 signaling via MTs.

CONCLUSIONS

These findings suggested that melatonin inhibited IAV infection, improved lung function and lung damages of AECOPD via suppressing IL-1β/STAT1-driven macrophage M1 polarization and apoptosis in a MTs-dependent manner. Melatonin may be considered as a potential therapeutic agent for influenza virus infection-induced AECOPD.

Dexamethasone protects against asthma via regulating Hif-1α-glycolysis-lactate axis and protein lactylation

PURPOSE

Asthma can not be eradicated till now and its control primarily relies on the application of corticosteroids. Recently, glycolytic reprogramming has been reportedly contributed to asthma, this study aimed to reveal whether the effect of corticosteroids on asthma control is related to their regulation of glycolysis and glycolysis-dependent protein lactylation.

METHODS

Ovalbumin (OVA) aeroallergen was used to challenge mice and stimulate human macrophage cell line THP-1 following dexamethasone (DEX) treatment. Airway hyperresponsiveness, airway inflammation, the expressions of key glycolytic enzymes and pyroptosis markers, the level of lactic acid, real-time glycolysis and oxidative phosphorylation (OXPHOS), and protein lactylation were analyzed.

RESULTS

DEX significantly attenuated OVA-induced eosinophilic airway inflammation, including airway hyperresponsiveness, leukocyte infiltration, goblet cell hyperplasia, Th2 cytokines production and pyroptosis markers expression. Meanwhile, OVA-induced Hif-1α-glycolysis axis was substantially downregulated by DEX, which resulted in low level of lactic acid. Besides, key glycolytic enzymes in the lungs of asthmatic mice were notably co-localized with F4/80-positive macrophages, indicating metabolic shift to glycolysis in lung macrophages during asthma. This was confirmed in OVA-stimulated THP-1 cells that DEX treatment resulted in reductions in pyroptosis, glycolysis and lactic acid level. Finally, protein lactylation was found significantly increased in the lungs of asthmatic mice and OVA-stimulated THP-1 cells, which were both inhibited by DEX.

CONCLUSION

Our present study revealed that the effect of DEX on asthma control was associated with its suppressing of Hif-1α-glycolysis-lactateaxis and subsequent protein lactylation, which may open new avenues for the therapy of eosinophilic asthma.

Melatonin regulates circadian clock proteins expression in allergic airway inflammation

Asthma demonstrates a strong circadian rhythm with disrupted molecular clock. Melatonin which can directly regulate circadian rhythm has been reported to alleviate asthma, but whether this effect is related to its regulation on circadian clock has not yet been known. Here, female C57BL/6 mice were challenged with ovalbumin (OVA) to establish allergic airway inflammation, and were treated with melatonin or Luzindole to investigate whether the expressions of circadian clock proteins were changed in response to OVA and were affected by exogenous/endogenous melatonin. Airway inflammation, mucus secretion, protein expressions of circadian proteins (Bmal1, Per1, Clock, Timeless, Cry1 and Cry2), melatonin biosynthetase (ASMT, AANAT) and melatonin receptor (Mel-1A/B-R) were analyzed accordingly. The results showed that in the successfully established allergic airway inflammation model, inflammatory cells infiltration, expressions of circadian clock proteins in the lung tissues of OVA-challenged mice were all notably up-regulated as compared to that of the vehicle mice. Meanwhile, the protein expression of ASMT and the level of melatonin in the lung tissues were reduced in allergic mice, while the expression of melatonin receptor Mel-1A/B-R was markedly increased. After addition of exogenous melatonin, the OVA-induced airway inflammation was pronouncedly ameliorated, while simultaneously the OVA-induced expressions of Per1 and Clock were further increased. However, a melatonin receptor antagonist Luzindole further augmented the OVA-induced airway inflammation, accompanied with remarkably decreased expressions of Per1, Bmal1, Cry1 and Cry2 but notably increased expression of Timeless. Collectively, our results demonstrated that the expression of circadian clock proteins was increased in the lungs during allergic airway inflammation, and Per1 was a clock protein that can be regulated by both exogenous and endogenous melatonin, suggesting Per1 may be an important potential circadian clock target for melatonin as a negative regulatory factor against Th2-type airway inflammation.

Differential Characteristics of Patients for Hospitalized Severe COVID-19 Infected by the Omicron Variants and Wild Type of SARS-CoV-2 in China

Background

As multiple mutations of SARS-Cov-2 exist, there are now many viral variants with regional differences in distribution. The clinical characteristics of patients hospitalized with the virus also vary significantly, with those of the Omicron variants being strikingly different from those of the earliest wild-type variant. However, comprehensive data on this subject is lacking. It is therefore crucial to explore these differences to develop better clinical strategies for the management of COVID-19.

Methods

A total of 554 confirmed COVID-19 cases in China were clinically classified as mild, moderate, severe, and critical according to their diagnoses and treatment plans. We compared the demographics and clinical characteristics of patients infected with the Omicron vs wild-type strains, between severe and non-severe cases. Bacterial co-infections with SARS-CoV-2 and correlation between inflammatory factors and T cells were analyzed.

Results

Compared to the wild-type cases, the severe Omicron cases were older (median age 48.36 vs 73.24), and had more upper-respiratory symptoms and comorbidities. Decreased leukocyte counts were less pronounced, although more instances of significantly decreased CD4+ and CD8+ T-cell counts, elevated infection-related biomarkers (eg procalcitonin and C-reactive protein), and abnormal coagulation factors (including increased D-dimer and fibrinogen levels) were detected in the severe Omicron cases. The mean length of hospital stay was significantly shorter in the severe Omicron cases. CD4+ and CD8+ T cell numbers were negatively correlated with neutrophil-to-lymphocyte ratios, as well as serum interleukin-6, procalcitonin, and C-reactive protein levels.

Conclusion

There were significant clinical differences between patients hospitalized with severe cases of Omicron- variant COVID-19 vs wild-type. The Omicron cases tended to be older and had more upper respiratory tract symptoms, comorbidities and bacterial co-infections. Elevated levels of inflammatory cytokines with T-cell depletion correlated with poor disease progression and prognosis. We hope these data provide a theoretical basis for future integrated prevention and control plans for COVID-19.

Exosome-derived circKIF20B suppresses gefitinib resistance and cell proliferation in non-small cell lung cancer

BACKGROUND

The gefitinib resistance mechanism in non-small cell lung cancer (NSCLC) remains unclear, albeit exosomal circular RNA (circRNA) is known to possibly play a vital role in it.

METHODS

We employed high-throughput sequencing techniques to detect the expressions of exosomal circRNA both in gefitinib-resistant and gefitinib-sensitive cells in this study. The circKIF20B expression was determined in serum exosomes and tissues of patients by qRT-PCR. The structure, stability, and intracellular localization of circKIF20B were verified by Sanger sequencing, Ribonuclease R (RNase R)/actinomycin D (ACTD) treatments, and Fluorescence in situ hybridization (FISH). The functions of circKIF20B were investigated by 5-Ethynyl-20-deoxyuridine (EdU), flow cytometry, Cell Counting Kit-8 (CCK-8), oxygen consumption rate (OCR), and xenograft model. Co-culture experiments were performed to explore the potential ability of exosomal circKIF20B in treating gefitinib resistance. The downstream targets of circKIF20B were determined by luciferase assay, RNA pulldown, and RNA immunoprecipitation (RIP).

RESULTS

We found that circKIF20B was poorly expressed in the serum exosomes of gefitinib-resistant patients (n = 24) and the tumor tissues of patients with NSCLC (n = 85). CircKIF20B was negatively correlated with tumor size and tumor stage. Decreasing circKIF20B was found to promote gefitinib resistance by accelerating the cell cycle, inhibiting apoptosis, and enhancing mitochondrial oxidative phosphorylation (OXPHOS), whereas increasing circKIF20B was found to restore gefitinib sensitivity. Mechanistically, circKIF20B is bound to miR-615-3p for regulating the MEF2A and then altering the cell cycle, apoptosis, and mitochondrial OXPHOS. Overexpressing circKIF20B parental cells can restore sensitivity to gefitinib in the recipient cells by upregulating the exosomal circKIF20B expression.

CONCLUSIONS

This study revealed a novel mechanism of circKIF20B/miR-615-3p/MEF2A signaling axis involving progression of gefitinib resistance in NSCLC. Exosomal circKIF20B is expected to be an easily accessible and alternative liquid biopsy candidate and potential therapeutic target in gefitinib-resistant NSCLC. The schematic diagram of mechanism in this study. Exosomal circKIF20B inhibits gefitinib resistance and cell proliferation by arresting the cell cycle, promoting apoptosis, and reducing OXPHOS via circKIF20B/miR-615-3p/MEF2A axis in NSCLC.

TLR2-hif1α-mediated glycolysis contributes to pyroptosis and oxidative stress in allergic airway inflammation

As a pattern recognition receptor which activates innate immune system, toll-like receptor 2 (TLR2) has been reportedly mediates allergic airway inflammation (AAI), yet the underlying mechanism remains elusive. Here, in a murine AAI model, TLR2^-/- mice showed decreased airway inflammation, pyroptosis and oxidative stress. RNA-sequencing revealed that allergen-induced hif1 signaling pathway and glycolysis were significantly downregulated when TLR2 was deficient, which were confirmed by lung protein immunoblots. Glycolysis inhibitor 2-Deoxy-d-glucose (2-DG) inhibited allergen-induced airway inflammation, pyroptosis, oxidative stress and glycolysis in wild type (WT) mice, while hif1α stabilizer ethyl 3,4-dihydroxybenzoate (EDHB) restored theses allergen-induced changes in TLR2^-/- mice, indicating TLR2-hif1α-mediated glycolysis contributes to pyroptosis and oxidative stress in AAI. Moreover, upon allergen challenge, lung macrophages were highly activated in WT mice but were less activated in TLR2^-/- mice, 2-DG replicated while EDHB reversed such effect of TLR2 deficiency on lung macrophages. Likewise, both in vivo and ex vivo WT alveolar macrophages (AMs) exhibited higher TLR2/hif1α expression, glycolysis and polarization activation in response to ovalbumin (OVA), which were all inhibited in TLR2^-/- AMs, suggesting AMs activation and metabolic switch are dependent on TLR2. Finally, depletion of resident AMs in TLR2^-/- mice abolished while transfer of TLR2^-/- resident AMs to WT mice replicated the protective effect of TLR2 deficiency on AAI when administered before allergen challenge. Collectively, we suggested that loss of TLR2-hif1α-mediated glycolysis in resident AMs ameliorates allergic airway inflammation that inhibits pyroptosis and oxidative stress, therefore the TLR2-hif1α-glycolysis axis in resident AMs may be a novel therapeutic target for AAI.

Influenza a virus triggers acute exacerbation of chronic obstructive pulmonary disease by increasing proinflammatory cytokines secretion via NLRP3 inflammasome activation

Background

Influenza A virus (IAV) triggers acute exacerbation of chronic obstructive pulmonary disease (AECOPD), but the molecular mechanisms remain unclear. In this study, we investigated the role of IAV induced NLRP3 inflammasome activation to increase airway inflammation response in the progression of AECOPD.

Methods

Human bronchial epithelial cells were isolated and cultured from normal and COPD bronchial tissues and co-cultured with IAV. The NLRP3 inflammasome associated genes were identified using RNA sequencing, and the expressions of NLRP3 inflammasome components were measured using qRT-PCR and western blot after cells were transfected with siRNA and treated with MCC950. Moreover, IAV-induced COPD rat models were established to confirm the results; 37 AECOPD patients were included to measure the serum and bronchoalveolar lavage fluid (BALF) of interleukin (IL)-18 and IL-1β.

Results

Increased levels of NLRP3 inflammasome components were not seen until 6 h post-inoculation in normal cells. However, both cell groups reached peak NLRP3 level at 12 h post-inoculation and maintained it for up to 24 h. ASC, Caspase-1, IL-1β and IL-18 were also elevated in a similar time-dependent pattern in both cell groups. The mRNA and protein expression of the NLRP3 inflammasome components were decreased when COPD cells treated with siRNA and MCC950. In COPD rats, the NLRP3 inflammasome components were elevated by IAV. MCC950 alleviated lung damage, improved survival time, and reduced NLRP3 inflammasome components expression in COPD rats. Additionally, the serum and BALF levels of IL-1β and IL-18 were increased in AECOPD patients.

Conclusions

NLRP3 inflammasome is activated in COPD patients as a pre-existing condition that is further exacerbated by IAV infection.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12950-022-00305-y.

Melatonin Suppresses Macrophage M1 Polarization and ROS-Mediated Pyroptosis via Activating ApoE/LDLR Pathway in Influenza A-Induced Acute Lung Injury

Influenza virus infection is one of the strongest pathogenic factors for the development of acute lung injury (ALI)/ acute respiratory distress syndrome (ARDS). However, the underlying cellular and molecular mechanisms have not been clarified. In this study, we aim to investigate whether melatonin modulates macrophage polarization, oxidative stress, and pyroptosis via activating Apolipoprotein E/low-density lipoprotein receptor (ApoE/LDLR) pathway in influenza A-induced ALI. Here, wild-type (WT) and ApoE-/- mice were instilled intratracheally with influenza A (H3N2) and injected intraperitoneally with melatonin for 7 consecutive days. In vitro, WT and ApoE-/- murine bone marrow-derived macrophages (BMDMs) were pretreated with melatonin before H3N2 stimulation. The results showed that melatonin administration significantly attenuated H3N2-induced pulmonary damage, leukocyte infiltration, and edema; decreased the expression of proinflammatory M1 markers; enhanced anti-inflammatory M2 markers; and switched the polarization of alveolar macrophages (AMs) from M1 to M2 phenotype. Additionally, melatonin inhibited reactive oxygen species- (ROS-) mediated pyroptosis shown by downregulation of malonaldehyde (MDA) and ROS levels as well as inhibition of the NLRP3/GSDMD pathway and lactate dehydrogenase (LDH) release. Strikingly, the ApoE/LDLR pathway was activated when melatonin was applied in H3N2-infected macrophages and mice. ApoE knockout mostly abrogated the protective impacts of melatonin on H3N2-induced ALI and its regulatory ability on macrophage polarization, oxidative stress, and pyroptosis. Furthermore, recombinant ApoE3 (re-ApoE3) inhibited H3N2-induced M1 polarization of BMDMs with upregulation of MT1 and MT2 expression, but re-ApoE2 and re-ApoE4 failed to do this. Melatonin combined with re-ApoE3 played more beneficial protective effects on modulating macrophage polarization, oxidative stress, and pyroptosis in H3N2-infected ApoE-/- BMDMs. Our study indicated that melatonin attenuated influenza A- (H3N2-) induced ALI by inhibiting the M1 polarization of pulmonary macrophages and ROS-mediated pyroptosis via activating the ApoE/LDLR pathway. This study suggested that melatonin-ApoE/LDLR axis may serve as a novel therapeutic strategy for influenza virus-induced ALI.

Interleukin-6 neutralizing antibody attenuates the hypersecretion of airway mucus via inducing the nuclear translocation of Nrf2 in chronic obstructive pulmonary disease

Airway mucus hypersecretion is a vital pathophysiologic feature in chronic obstructive pulmonary disease (COPD) patients in which airflow limitation result, and it is key to strategizing in the management of COPD. To investigate the mechanisms underlying the action of interleukin-6 neutralizing antibody (IL-6 Ab) in attenuating airway mucus hypersecretion in COPD, human and mouse primary bronchial epithelial cells from COPD patients and mice were isolated, human organoid model of trachea was established and all treated with IL-6 and/or IL-6 Ab. The differential expression of Muc5ac and Nrf2 were determined in pDHBE compared to pNHBE cells via high-throughput sequencing of transcriptome. The serum concentration of Muc5ac was significantly elevated and positively correlated with IL-6 in COPD patients using ELISA, and the excessive mucus secretion was observed in the trachea of COPD patients using HE, AB-PAS and IHC staining. The levels of Muc5ac were significantly elevated in the IL-6-treated group, and diminished with IL-6 Ab treatment, both in vitro and in the organoid model using qRT-PCR, WB and IF. The expression levels of protein Muc5ac were significantly reduced in cells transfected with the IL-6 small interfering RNA (siRNA-IL-6), which was in contrast to the levels of protein Nrf2, and the protective effects of IL-6 Ab were inhibited in cells transfected with Nrf2 short hairpin RNA (shRNA-Nrf2). IL-6 Ab significantly attenuated hypersecretion of airway mucus by inducing nuclear translocation of Nrf2 in COPD. These findings indicated that IL-6 Ab may constitute a novel therapeutic agent for IL-6-induced airway mucus hypersecretion by improving airflow limitation in COPD patients.

Melatonin attenuates LPS-induced pyroptosis in acute lung injury by inhibiting NLRP3-GSDMD pathway via activating Nrf2/HO-1 signaling axis

Acute lung injury (ALI)/ acute respiratory distress syndrome (ARDS) is featured by intensive inflammatory responses and oxidative stress, which lead to cytokine storms and pyroptosis. Here, we aimed to investigate whether melatonin was capable of alleviating LPS-induced ALI via activating the nuclear factor erythroid 2-related factor 2/heme oxygenase 1 (Nrf2/HO-1) signaling axis and inhibiting pyroptosis. Mice were injected with melatonin (30 mg/kg) intraperitoneally for consecutive five days before LPS instillation intratracheally, and human alveolar epithelial cell (AECⅡ) A549 cell lines and murine macrophages Raw264.7 cell lines were pretreated with melatonin (400 μM) before LPS (10 μg/ml) stimulation. The result demonstrated that LPS induced obvious lung injury characterized by alveolar damage, neutrophil infiltration and lung edema as well as the reduction of the survival rate of mice, which were totally reversed by melatonin pretreatment. Mechanistically, melatonin pretreatment activated nuclear factor erythroid2-related factor (Nrf) 2 signaling, subsequently, drove antioxidant pathways including significant increases in the expression of Nrf2, HO-1, NQO1, Mn-SOD and Catalase in vivo and in vitro. Simultaneously, melatonin inhibited ROS and MDA overproduction, iNOS expression as well as TNF-α and IL-1β expression and release. Furthermore, melatonin inhibited LPS-induced pyroptosis by reversing the overexpression of NLRP3, Caspase-1, IL-1β, IL-18 and GSDMD-N, as well as LDH release and TUNEL-positive cells in A549 cells and Raw264.7 cells. Overall, the current study suggests that melatonin exerts protective roles on LPS-induced ALI and pyroptosis by inhibiting NLRP3-GSDMD pathway via activating Nrf2/HO-1 signaling axis.

CD19 and POU2AF1 are Potential Immune-Related Biomarkers Involved in the Emphysema of COPD: On Multiple Microarray Analysis

Purpose

Emphysema is the main cause of the progression of chronic obstructive pulmonary disease (COPD). This study aimed to identify the key genes involved in COPD-related emphysema.

Patients and Methods

GSE76925 was downloaded from Gene Expression Omnibus database. Protein–protein interaction networks of differentially expressed genes (DEGs) between control and COPD groups were constructed to identify hub genes using Cytoscape. Diagnostic performance of hub genes was evaluated using receiver operating characteristic analysis. Correlation analysis was performed to identify the key genes by analyzing the relationship between the hub genes and lung function and computed tomography (CT) indexes of emphysema. COPD patients were then divided into two groups based on the median expression of key genes and DEGs between these two groups were identified. Enrichment analysis of DEGs and correlation analysis between key genes and the infiltration of the immune cells were also analyzed. Finally, the role of key genes was evaluated in a lung tissues dataset (GSE47460) and a blood dataset (GSE76705). Additionally, the expression of key genes was validated by quantitative real-time polymerase chain reaction and immunohistochemistry.

Results

CD19 and POU2AF1 had diagnostic efficacy for COPD and were significantly correlated with lung function and CT indexes of emphysema. Enrichment and immune analyses revealed that CD19 and POU2AF1 were correlated with the B cells in COPD. These results were consistent in GSE47460. The expression of CD19 and POU2AF1 in blood was the opposite of that in lung tissues, and CD19 and POU2AF1 were both significantly upregulated in COPD lung tissues at both the mRNA and protein levels.

Conclusion

CD19 and POU2AF1 may serve as key regulators of emphysema and contribute to the progression of COPD by regulating the B-cell immunology. Targeting B cells may be a promising strategy for treating COPD.

[Correlation between systemic inflammation level and emphysema degree and bone mineral density in chronic obstructive pulmonary disease patients and its mechanism]

Objective: To study the correlation between systemic inflammation level and emphysema degree and bone mineral density in chronic obstructive pulmonary disease (COPD) patients and its possible mechanism. Methods: 90 patients with stable COPD who met the inclusion criteria and 50 controls in the physical examination center during the same period were recruited. All the enrolled objects have collected general clinical data, analyzed peripheral blood samples, measuring the Low-attenuation area of lung and CT value of lumbar 1 vertebra (L1-CT) by chest spiral CT. According to LAA%, COPD patients were divided into 36 cases of the non-emphysema group, 32cases of mild to moderate emphysema group, and 22 cases of severe emphysema group. The correlation between L1-CT value, LAA%, peripheral blood inflammatory factors, and pulmonary function indices in each group was analyzed and compared. Results: The HU value of L1-CT (107±32) in the COPD group was significantly lower than that in the control group (153±30), and the difference was statistically significant (P<0.05). The higher the LAA% in COPD patients was, the lower the value of L1-CT was, and the difference between groups was statistically significant. Compared with COPD patients in the non-emphysema group, peripheral blood neutrophil/lymphocyte ratio (NLR), platelet/lymphocyte ratio (PLR), and C-reactive protein (CRP) were all increased in the emphysema group, and the differences were statistically significant (P<0.05). L1-CT was negatively correlated with LAA, PLR, NLR, and CRP while uncorrelated with serum concentration of calcium and phosphorus. Conclusion: The decrease in bone density in COPD patients is closely related to the degree of emphysema. It is associated with increased levels of systemic inflammation caused by COPD itself. Early and timely broad-spectrum anti-inflammatory treatment may have certain clinical significance for the prevention and treatment of comorbidity with osteoporosis.

The Influenza A Virus H3N2 Triggers the Hypersusceptibility of Airway Inflammatory Response via Activating the lncRNA TUG1/miR-145-5p/NF-κB Pathway in COPD

Background: Patients with chronic obstructive pulmonary disease (COPD) are more susceptible to influenza A virus (IAV) with more severe symptoms, yet the underlying molecular mechanisms of the hypersusceptibility of airway inflammatory response remain unclear. Methods: The primary human bronchial epithelial cells (pHBECs) were isolated from normal and COPD bronchial tissues (NHBE and DHBE) and cultured with/without IAV infection in vitro. DHBE cells were exposed to IAV for 24 h after knockdown of lncRNA TUG1 with short hairpin RNA (shRNA). Gain-of-function assays were performed with the miR-145-5p inhibitor and NF-κBp65 transfection. The expressions of lncRNA TUG1, miR-145-5p, phospho-NF-κBp65, NF-κBp65, TNF-α, and (Interleukin) IL-1β were examined with qRT-PCR, Western blotting, and ELISA. The interactions of lncRNA TUG1, miR-145-5p, and NF-κB were verified with luciferase reporter assay. Results: The expressions of lncRNA TUG1, phospho-NF-κBp65, TNF-α, and IL-1β were increased significantly in pHBECs after being infected with IAV for 24 h (all p0.05). The detailed time analysis revealed that the NF-κBp65 in DHBE was activated earlier than that in NHBE by Western blotting and immunofluorescence. Knockdown of lncRNA TUG1 and miR-145-5p mimic attenuated the expressions of NF-κBp65, TNF-α, and IL-1β significantly. The miR-145-5p inhibitor and NF-κBp65 transfection reversed the attenuated expressions of NF-κBp65, TNF-α, and IL-1β. Conclusion: The IAV causes the hypersusceptibility of airway inflammatory response, which may be closely associated with more severe symptoms in AECOPD patients. The lncRNA TUG1 inhibitor may be a promising therapeutic strategy for AECOPD caused by IAV.

ResolvinD1 Protects the Airway Barrier Against Injury Induced by Influenza A Virus Through the Nrf2 Pathway

Airway barrier damage and excessive inflammation induced by influenza A virus (IAV) are associated with disease progression and prognosis. ResolvinD1 (RvD1) is a promising lipid mediator with critical protection against infection in the lung. However, whether RvD1 protects against IAV-induced injury and the underlying mechanisms remain elusive. In this study, primary normal human bronchial epithelial (pNHBE) cells were isolated and co-cultured with IAV and/or RvD1. Then, the expressions of E-cadherin, Zonula occludins-1, inflammatory mediators and proteins in Nrf2-dependent pathway were detected. To further explore the mechanisms, Nrf2 short hairpin RNA (Nrf2 shRNA) was applied in pNHBE cells. Furthermore, mice were infected with IAV, and were subsequently treated with RvD1. We found that IAV downregulated expressions of E-cadherin, Zonula occludins-1, Nrf2 and HO-1, upregulated the phosphorylation of NF κ B p65 and IKBα, levels of IL-8 and TNF-α, as well as ROS production. RvD1 reversed these damaging effects induced by IAV. However, when Nrf2 expression was suppressed with shRNA in pNHBE cells, the protective effects of RvD1 on IAV-induced injury were inhibited. In vivo studies further demonstrated that RvD1 could alleviate barrier protein breakdown and reduce airway inflammatory reactions. Collectively, the study demonstrated that RvD1 could play dual beneficial roles in protecting airway epithelium barrier function and reducing inflammation via the Nrf2 pathway, which may provide a better treatment option for influenza A virus infection.

Abscisic acid suppresses the activation of NLRP3 inflammasome and oxidative stress in murine allergic airway inflammation

Abscisic acid (ABA), a well-known natural phytohormone reportedly exerts anti-inflammatory and anti-oxidative properties in diabetes and colitis. However, the efficacy of ABA against allergic airway inflammation and the underlying mechanism remain unknown. Herein, an OVA-induced murine allergic airway inflammation model was established and treated with ABA in the presence or absence of PPAR-γ antagonist GW9662. The results showed that ABA effectively stunted the development of airway inflammation, and concordantly downregulated OVA-induced activation of NLRP3 inflammasome, suppressed oxidative stress and decreased the expression of mitochondrial fusion/fission markers including Optic Atrophy 1 (OPA1), Mitofusion 2 (Mfn2), dynamin-related protein 1 (DRP1) and Fission 1 (Fis1). Moreover, ABA treatment further increased OVA-induced expression of PPAR-γ, while GW9662 abrogated the inhibitory effect of ABA on allergic airway inflammation as well as on the activation of NLRP3 inflammasome and oxidative stress. Consistently, ABA inhibited the activation of NLRP3 inflammasome, suppressed oxidative stress and mitochondrial fusion/fission in LPS-stimulated Raw264.7 cells via PPAR-γ. Collectively, ABA ameliorates OVA-induced allergic airway inflammation in a PPAR-γ dependent manner, and such effect of ABA may be associated with its inhibitory effect on NLRP3 inflammasome and oxidative stress. Our results suggest the potential of ABA or ABA-rich food in protecting against asthma.

Correlation between sestrin2 expression and airway remodeling in COPD

BACKGROUND

Airway remodeling is a major pathological characteristic of chronic obstructive pulmonary disease (COPD), and has been shown to be associated with oxidative stress. Sestrin2 has recently drawn attention as an important antioxidant protein. However, the underlying correlation between sestrin2 and airway remodeling in COPD has yet to be clarified.

METHODS

A total of 124 subjects were enrolled in this study, including 62 control subjects and 62 COPD patients. The pathological changes in airway tissues were assessed by different staining methods. The expression of sestrin2 and matrix metalloproteinase 9 (MMP9) in airway tissues was monitored by immunohistochemistry. Enzyme-linked immunosorbent assays (ELISAs) were used to detect the serum concentrations of sestrin2 and MMP9. The airway parameters on computed tomography (CT) from all participants were measured for evaluating airway remodeling. The relationship between serum sestrin2 and MMP9 concentration and airway parameters in chest CT was also analyzed.

RESULTS

In patients with COPD, staining of airway structures showed distinct pathological changes of remodeling, including cilia cluttered, subepithelial fibrosis, and reticular basement membrane (Rbm) fragmentation. Compared with control subjects, the expression of sestrin2 and MMP9 was significantly increased in both human airway tissues and serum. Typical imaging characteristics of airway remodeling and increased airway parameters were also found by chest CT. Additionally, serum sestrin2 concentration was positively correlated with serum MMP9 concentration and airway parameters in chest CT.

CONCLUSION

Increased expression of sestrin2 is related to airway remodeling in COPD. We demonstrated for the first time that sestrin2 may be a novel biomarker for airway remodeling in patients with COPD.

[Influenza virus activates toll-like receptor 7/nuclear factor-κB signaling pathway to regulate airway inflammatory response in patients with acute exacerbation of chronic obstructive pulmonary diseases]

Objective: To explore how influenza A virus (IAV) regulates airway inflammation via activating Toll-like receptor 7(TLR7)/nuclear factor of κB (NF-κB) signaling pathway in patients with acute exacerbation of chronic obstructive pulmonary disease (COPD). Methods: Primary bronchial epithelial cells were isolated and cultured from normal controls and COPD patients. Samples were divided into 6 groups according to different in vitro treatment, including normal epithelial cell group (A), normal cells+IAV group (B), COPD epithelial cell group (C), COPD cells+IAV group (D), normal cells+TLR7 small interference RNA (si-RNA) group (E), COPD cells+TLR7 siRNA group (F). Protein expressions of TLR7 and NF-κB were detected by Western blot after 24h co-culture with IAV and TLR7 siRNA. Interleukin-6 (IL-6) and tumor necrosis factor α (TNF α) were detected by enzyme-linked immunosorbent assay (ELISA). Results: (1) Compared with group A [0.350±0.075 and 0.470±0.034, (53.000±6.532)pg/ml and (17.000±1.625)pg/ml],TLR7, NF-κB protein expression and IL-6, TNF α levels were significantly increased in group B[0.950±0.075 and 1.090±0.078,(185.000±7.874)pg/ml and (32.000±0.838)pg/ml], group C[0.780±0.056 and 0.910±0.045,(138.000±5.100)pg/ml and 29.000±1.323)pg/ml) and group D[1.280±0.031 and 1.540±0.051,(432.000±5.734)pg/ml and (52.000±3.453)pg/ml] (all P<0.01). Compared with group C TLR7, NF-κB protein expression and IL-6, TNF α levels were significantly increased in group D (P<0.01). (2) Compared with the group A[0.530±0.023 and 0.800±0.046,(51.000±0.327)pg/ml and (14.000±0.314)pg/ml], TLR7, NF-κB protein expression and IL-6, TNF α levels were significantly decreased in the group E[0.350±0.047 and 0.510±0.067,(26.000±1.081)pg/ml and(8.000±0.526)pg/ml] (P<0.05). Compared with group C[1.080±0.078 and 1.280±0.034,(125.000±2.249)pg/ml and (28.000±1.010)pg/ml], TLR7, NF-κB protein expression and IL-6, TNF α levels decreased in the group F[0.880±0.056 and 1.040±0.029,(83.000±1.125)pg/ml and (21.000±0.429)pg/ml] (P<0.05). Conclusion: Influenza viruses activate TLR7/NF-κB signaling pathway to regulate airway inflammation storms in patients with acute exacerbation of COPD. New therapeutic targets of acute exacerbation COPD may be studied based on these inflammation responses to influenza viruses.

Shufeng Jiedu capsules for treating acute exacerbations of chronic obstructive pulmonary disease: a systematic review and meta-analysis

Background

Chinese herbal medicine is widely used in combination with usual care for acute exacerbations of chronic obstructive pulmonary disease (AECOPD) in China. Chinese patent medicine Shufeng Jiedu (SFJD) capsules is widely used for respiratory infectious diseases. This review aims to evaluate effectiveness and safety of SFJD for AECOPD.

Methods

A systematic review of randomised controlled trials (RCTs) in patients with AECOPD, who received SFJD as a single intervention or as add-on treatment to usual care. PubMed, the Cochrane Library, EMBASE, Scopus, Web of Science and four Chinese databases were searched from inception to April 2019. Two authors screened trials, extracted data, and assessed risk of bias, independently. Meta-analysis was performed using RevMan 5.3 software. We performed subgroup analyses and sensitivity analyses according to the predefined protocol. Quality of evidence was assessed using GRADE.

Results

Thirteen RCTs (1036 patients, with 936 inpatients) were included, all compared SFJD in combination with usual care (including antibiotics) to usual care alone. The mean age of participants ranged from 52 to 67 years, with approximately 60% male. Due to lack of blinding and other factors, all trials were of high risk of bias. SFJD was associated with a significant reduction in treatment failure, from 20.1 to 8.3% (11 trials; 815 patients; relative risk 0.43, 95% confidence interval [CI] 0.30 to 0.62), and duration of hospital stay (2 trials; 79 patients; mean difference − 4.32 days, 95% CI − 5.89 to − 2.75 days). No significant difference in adverse events was found between SFJD and control groups.

Conclusion

Low certainty evidence suggests SFJD may bring additional benefit in reducing treatment failure, shorten hospital stay, and improving symptoms. Further large, high quality RCTs are needed to confirm its benefit and safety.

Trial registration

PROSPERO CRD42019133682.

Apolipoprotein E negatively regulates murine allergic airway inflammation via suppressing the activation of NLRP3 inflammasome and oxidative stress

Apolipoprotein E (ApoE) has been reported as a steroid unresponsive gene and functions as a negative regulator of airway hyperreactivity (AHR) and goblet cell hyperplasia in house dust mite (HDM)-challenged mice. However, the role of ApoE in Ovalbumin (OVA)-induced allergic airway inflammation disease and the underlying mechanism are still unknown. In the present study, murine allergic airway inflammation was induced by inhaled OVA for consecutive 7 days in wild type (WT) and ApoE^-/- mice. In the OVA-induced model, the ApoE level in the bronchoalveolar lavage fluid (BALF) and lung tissues was significantly higher than that of control mice. And ApoE deficiency aggravated airway inflammation including leukocytes infiltration, goblet cell hyperplasia and IgE production as compared to those of WT mice after OVA- challenged, suggesting ApoE servers as an endogenous negative regulator of airway inflammation. Furthermore, OVA challenge elevated the activation of NLRP3 inflammasome with higher protein expression of NLRP3, caspase1 and IL-1β, enhanced oxidative stress with higher expression of 8-OHdG, nitrotyrosine and SOD2, increased the expression of mitochondrial fusion/fission markers including Optic Atrophy 1 (OPA1), Mitofusion 2 (Mfn2), dynamin-related protein 1 (DRP1) and Fission 1 (Fis1). However, these OVA-induced changes were augmented in ApoE^-/- mice. Collectively, our results demonstrated that the OVA-induced airway inflammation was aggravated in ApoE^-/- mice, and suggested that the underlying mechanism may be associated with the augmented activation of NLRP3 inflammasome and oxidative stress in ApoE^-/- mice, therefore targeting ApoE pathway might be a novel therapy approach for allergic airway diseases such as asthma.

TLR2-Melatonin Feedback Loop Regulates the Activation of NLRP3 Inflammasome in Murine Allergic Airway Inflammation

Toll-like receptor 2 (TLR2) is suggested to initiate the activation of NLRP3 inflammasome, and considered to be involved in asthma. The findings that melatonin modulates TLRs-mediated immune responses, together with the suppressing effect of TLRs on endogenous melatonin synthesis, support the possibility that a feedback loop exists between TLRs system and endogenous melatonin synthesis. To determine whether TLR2-melatonin feedback loop exists in allergic airway disease and regulates NLRP3 inflammasome activity, wild-type (WT) and TLR2^−/− mice were challenged with OVA to establish allergic airway disease model. Following OVA challenge, WT mice exhibited increased-expression of TLR2, activation of NLRP3 inflammasome and marked airway inflammation, which were all effectively inhibited in the TLR2^−/− mice, indicating that TLR2-NLRP3 mediated airway inflammation. Meanwhile, melatonin biosynthesis was reduced in OVA-challenged WT mice, while such reduction was notably rescued by TLR2 deficiency, suggesting that TLR2-NLRP3-mediated allergic airway inflammation was associated with decreased endogenous melatonin biosynthesis. Furthermore, addition of melatonin to OVA-challenged WT mice pronouncedly ameliorated airway inflammation, decreased TLR2 expression and NLRP3 inflammasome activation, further implying that melatonin in turn inhibited airway inflammation via suppressing TLR2-NLRP3 signal. Most interestingly, although melatonin receptor antagonist luzindole significantly reduced the protein expressions of ASMT, AANAT and subsequent level of melatonin in OVA-challenged TLR2^−/− mice, it exhibited null effect on leukocytes infiltration, Th2-cytokines production and NLRP3 activity. These results indicate that a TLR2-melatonin feedback loop regulates NLRP3 inflammasome activity in allergic airway inflammation, and melatonin may be a promising therapeutic medicine for airway inflammatory diseases such as asthma.

Melatonin biosynthesis restored by CpG oligodeoxynucleotides attenuates allergic airway inflammation via regulating NLRP3 inflammasome

AIMS

Both CpG oligodeoxynucleotide (CpG-ODN) and melatonin have been reported to induce Th1 response and contribute to allergic asthma resistance. Here, we aimed to reveal how they confer such effect as well as whether they crosstalk with each other.

MAIN METHODS

Six-week-old Female C57BL/6 mice were challenged by OVA to induce allergic airway inflammation, and were treated with CpG-ODN, CpG-ODN plus Luzindole or melatonin respectively. Bronchoalveolar lavage fluid (BALF) cellularity was classified and counted by Wright's-Giemsa staining. HE and PAS staining were used to analyze airway inflammation. The levels of IL-4, IL-5, IL-13,GM-CSF and IFN-γ, as well as IL-1β and IL-18 were analyzed by ELISA. Protein expressions of ASMT, AANAT, NLRP3, IL-1β and caspase-1 in lung tissue were detected by Western blotting, expression of ASMT and AANAT were further observed by immunohistochemistry.

KEY FINDINGS

We found that CpG-ODN considerably suppressed OVA-induced airway leukocytes infiltration, goblet cell hyperplasia and Th2 cytokines production. Furthermore, the resolution effect of CpG-ODN on OVA-induced allergic airway inflammation occurred in parallel with decreased-activation of NLRP3 inflammasome and increased biosynthesis of melatonin. Blocking the effect of endogenous melatonin by Luzindole abolished the suppressive effect of CpG-ODN on OVA-induced airway inflammation and activation of NLRP3 inflammasome, suggesting such effect was mediated by endogenous melatonin. Moreover, exogenous melatonin pronouncedly ameliorated airway inflammation and decreased the activation of NLRP3 inflammasome.

SIGNIFICANCE

These results proven that CpG-ODN protects against allergic airway inflammation via suppressing the activation of NLRP3 inflammasome, and such effect may be resulted from the restored-production of melatonin.

Unique synergistic antiviral effects of Shufeng Jiedu Capsule and oseltamivir in influenza A viral-induced acute exacerbation of chronic obstructive pulmonary disease

BACKGROUND

The aim of the present study was to investigate the synergistic effects and interactive mechanisms of Shufeng Jiedu Capsule (SFJDC) combined with oseltamivir in the treatment of acute exacerbation of chronic obstructive pulmonary disease (AECOPD) induced by the influenza A virus (IAV).

METHODS

The extraction of SFJDC was analyzed by UHPLC/ESI Q-Orbitrap Mass Spectrometry. Human bronchial epithelial cells were isolated from COPD (DHBE) bronchial tissues, co-cultured with IAV for 24 h, and were subsequently treated with SFJDC and/or oseltamivir. Cell viability was detected by MTT assay. A rat model of COPD with IAV infection was established and treated with SFJDC and/or oseltamivir. Interleukin (IL)-1β and IL-18 in serum and bronchoalveolar lavage fluid (BALF) were measured by ELISA. Additionally, mRNA and protein levels of NLRP3 inflammasome pathway were measured by quantitative real-time PCR and Western blotting, respectively.

RESULTS

SFJDC and/or oseltamivir, at their optimal concentrations, had no significant cytotoxicity against DHBEs. The levels of NLRP3-inflammasome-associated components were significantly elevated after cells were inoculated with IAV, whereas the mRNA and protein levels of these components were significantly decreased after treatment with SFJDC and/or oseltamivir in vitro. Moreover, in vivo, the combination of SFJDC and oseltamivir improved survival rates, attenuated clinical symptoms, induced weight gain, alleviated lung damage, and significantly reduced IL-1β and IL-18 levels in serum and BALF, as well as reduced the expression levels of NLRP3-associated components and viral titers in lung homogenates.

CONCLUSION

SFJDC combined with oseltamivir treatment significantly attenuated IAV-induced airway inflammation and lung viral titers. Hence, our findings may provide a novel therapeutic strategy for IAV-induced respiratory infection.

[Association of sleep-disorders with systemic inflammatory markers and acute exacerbation in chronic obstructive pulmonary disease patients]

Objective: To investigate the association of sleep quality with the levels of systemic inflammatory markers in patients with chronic obstructive pulmonary disease(COPD) and the correlations between the frequency of acute exacerbation of COPD (AECOPD) and Pittsburgh sleep quality index (PSQI). Methods: A total of 198 COPD patients admitted in our hospital from October, 2016 to June, 2017 were screened, and 124 patients were eligible for the study. On the first day of hospitalization, the serum samples and clinical data were collected, including white blood cells, lymphocytes, platelet count, CRP and PSQI. Poor sleep quality was defined as PSQI score >5. Results: The percentage of COPD patients with poor sleep quality was about 68%. Poor sleep quality was positively correlated with the frequency of acute exacerbation in COPD patients. The ratio of neutrophil to lymphocyte (NLR), ratio of platelet to lymphocyte (PLR) and levels of CRP were higher in patients with poor sleep quality than those in the control group. NLR, PLR and CRP in peripheral blood of the patients with poor sleep quality were positively correlated with PSQI score. The CRP levels and PSQI score in COPD patients with poor sleep quality group were positively correlated with the frequency of exacerbations in the past year (r=0.437, r=0.430). Conclusion: A high percentage of COPD patients had poor sleep quality, which was positively correlated with the levels of systemic inflammation as well as the frequency of AECOPD.

Respiratory infectious phenotypes in acute exacerbation of COPD: an aid to length of stay and COPD Assessment Test

Purpose

To investigate the respiratory infectious phenotypes and their impact on length of stay (LOS) and the COPD Assessment Test (CAT) Scale in acute exacerbation of COPD (AECOPD).

Patients and methods

We categorized 81 eligible patients into bacterial infection, viral infection, coinfection, and non-infectious groups. The respiratory virus examination was determined by a liquid bead array xTAG Respiratory Virus Panel in pharyngeal swabs, while bacterial infection was studied by conventional sputum culture. LOS and CAT as well as demographic information were recorded.

Results

Viruses were detected in 38 subjects, bacteria in 17, and of these, seven had both. Influenza virus was the most frequently isolated virus, followed by enterovirus/rhinovirus, coronavirus, bocavirus, metapneumovirus, parainfluenza virus types 1, 2, 3, and 4, and respiratory syncytial virus. Bacteriologic analyses of sputum showed that Pseudomonas aeruginosa was the most common bacteria, followed by Acinetobacter baumannii, Klebsiella, Escherichia coli, and Streptococcus pneumoniae. The longest LOS and the highest CAT score were detected in coinfection group. CAT score was positively correlated with LOS.

Conclusion

Respiratory infection is a common causative agent of exacerbations in COPD. Respiratory coinfection is likely to be a determinant of more severe acute exacerbations with longer LOS. CAT score may be a predictor of longer LOS in AECOPD.

A study on the effect of IL-6 gene polymorphism on the prognosis of non-small-cell lung cancer

Background

Lung cancer is one of the most commonly diagnosed clinical diseases. IL-6 is a multifunctional cytokine that is related to chemotactic factors and tumor biological regulation. −174G/C polymorphism in the promoter region of the IL-6 gene single-nucleotide polymorphism is the −174 position change from G to C. However, the relationship between the IL-6 gene polymorphism and prognosis of lung cancer is elusive. Therefore, the aim of this study was to evaluate the effect of −174G/C polymorphism on the prognosis of patients with non-small-cell lung cancer (NSCLC).

Methods

DNA was extracted from the peripheral blood of 434 cases diagnosed with NSCLC by cytologic or histologic examination. Polymerase chain reaction–restriction fragment length polymorphism (NlaIII) was used to detect the genotype of −174G/C. Based on the functional activity of the IL-6 gene polymorphism, genotypes were divided into G vector (CG/GG) (high yield) and CC genotype (low yield). Prognosis of patients was analyzed and independent risk factors evaluated. A quantitative analysis of the degree of pain after diagnosis was performed to evaluate the correlations between gene polymorphisms and the degree of pain and use of analgesics.

Results

Survival analysis showed that survival of the patients carrying the G allele (CG/GG) was significantly lower than that of patients with CC genotype (42.31 versus 62.79 months; P=0.032). The IL-6 gene promoter region revealed the presence of polymorphic variants, which may be associated with changes in the gene transcription process that affect the level of serum cytokines. IL-6 −174G/C gene polymorphism is associated with a significant morphine equivalent daily dose (IL-6 GG, 69.61; GC, 73.17; CC, 181.67; P=0.004). Homozygous IL-6 −174C/C genotype carriers required higher doses of opioids than GG or GC carriers.

Conclusion

Polymorphism of −174G/C in IL-6 is closely related to cancer pain in NSCLC patients, the use of analgesics, and survival prognosis. It is necessary to further confirm the related results and determine the underlying pathogenic mechanisms.

The COPD assessment test correlates well with the computed tomography measurements in COPD patients in China

Background

The chronic obstructive pulmonary disease (COPD) assessment test (CAT) is a validated simple instrument to assess health status, and it correlates well with the severity of airway obstruction in COPD patients. However, little is known about the relationships between CAT scores and quantitative computed tomography (CT) measurements of emphysema and airway wall thickness in COPD patients in the People’s Republic of China.

Methods

One hundred and twelve participants including 63 COPD patients and 49 normal control subjects were recruited. All participants were examined with high-resolution CT to get the measurements of emphysema (percentage of pixels below −950 HU [%LAA–950]) and airway wall thickness (wall area percentage and the ratio of airway wall thickness to total diameter). Meanwhile, they completed the CAT and modified Medical Research Council questionnaire independently.

Results

Significantly higher CAT scores and CT measurements were found in COPD patients compared with normal control subjects (P<0.05), and there was a tendency of higher CAT scores and CT measurements with increasing disease severity measured by GOLD staging system. Positive correlations were found between CAT scores and CT measurements (P<0.01). Using multiple linear stepwise regression, CAT score =−46.38+0.778× (wall area percentage) +0.203× (%LAA–950) (P<0.001). Meanwhile, CAT scores and CT measurements in COPD patients all positively correlated with the modified Medical Research Council grades and negatively correlated with FEV₁% (P<0.01).

Conclusion

CAT scores correlate well with the quantitative CT measurements in COPD patients, which may provide an imaging evidence that the structural changes of the lungs in this disease are associated with the health status measured by CAT.

Utility of the CAT in the therapy assessment of COPD exacerbations in China

BACKGROUND

Chronic obstructive pulmonary disease (COPD) exacerbations are accompanied with increased systemic inflammation, which accelerate the pulmonary function injury and impair the quality of life. Prompt and effective treatments for COPD exacerbations slow down the disease progression, but an objective instrument to assess the efficacy of the treatments following COPD exacerbations is lacking nowadays. The COPD Assessment Test (CAT) is an 8-item questionnaire designed to assess and quantify health status and symptom burden in COPD patients. We hypothesize that the change in CAT score is related to the treatment response following COPD exacerbations.

METHODS

78 inpatients with clinician-diagnosed acute exacerbation of COPD (AECOPD) completed the CAT, St George's Respiratory Questionnaire (SGRQ) and modified Medical Research Council (mMRC) Dyspnea Scale both at exacerbation and the 7th day of therapy, and a subgroup of 39 patients performed the pulmonary function test. Concentrations of serum C-reactive protein (CRP) and plasma fibrinogen were assayed at the same time. Correlations between the CAT and other measurements were examined.

RESULTS

After 7 days' therapy, the CAT and SGRQ scores, mMRC grades, as well as the concentrations of CRP and fibrinogen all decreased significantly (P < 0.001). Meanwhile, the FEV1% predicted had a significant improvement (P < 0.001). The CAT scores were significantly correlated with concurrent concentrations of CRP and fibrinogen, SGRQ scores, FEV1% predicted and mMRC grades (P < 0.05). The change in CAT score was positively correlated with the change of CRP (r = 0.286, P < 0.05), SGRQ score (r = 0.725, P < 0.001) and mMRC grades (r = 0.593, P < 0.001), but not with fibrinogen (r = 0.137, P > 0.05) or FEV1% predicted (r = -0.101, P > 0.05). No relationship was found between the changes of SGRQ score and CRP and fibrinogen (P>0.05).

CONCLUSIONS

The CAT is associate with the changes of systemic inflammation following COPD exacerbations. Moreover, the CAT is responsive to the treatments, similar to other measures such as SGRQ, mMRC dyspnea scale and pulmonary function. Therefore, the CAT is a potentially useful instrument to assess the efficacy of treatments following COPD exacerbations.

The unique alterations of hippocampus and cognitive impairment in chronic obstructive pulmonary disease

Background

Cognitive impairment has been found in chronic obstructive pulmonary disease (COPD) patients. However, the structural alteration of the brain and underlying mechanisms are poorly understood.

Methods

Thirty-seven mild-to-moderate COPD patients, forty-eight severe COPD patients, and thirty-one control subjects were recruited for cognitive test and neuroimaging studies. Serum levels of S100B,pulmonary function and arterial blood gas levels were also evaluated in each subject.

Results

The hippocampal volume was significantly smaller in COPD patients compared to the control group. It is positively correlated with a mini mental state examination (MMSE) score, SaO₂ in mild-to-moderate COPD patients, the levels of PaO₂ in both mild-to-moderate and severe COPD patients. Higher S100B concentrations were observed in mild-to-moderate COPD patients, while the highest S100B level was found in severe COPD patients when compared to the control subjects. S100B levels are negatively associated with MMSE in both mild-to-moderate and severe COPD patients and also negatively associated with the hippocampal volume in the total COPD patients.

Conclusions

Hippocampal atrophy based on quantitative assessment by magnetic resonance imaging does occur in COPD patients, which may be associated with cognitive dysfunction and the most prevalent mechanism accountable for hippocampal atrophy is chronic hypoxemia in COPD. Higher serum S100B levels may be peripheral biochemical marker for cognitive impairment in COPD.

Neuronal calcium sensor-1 modulation of optimal calcium level for neurite outgrowth

Neurite extension and branching are affected by activity-dependent modulation of intracellular Ca2+, such that an optimal window of [Ca2+] is required for outgrowth. Our understanding of the molecular mechanisms regulating this optimal [Ca2+]i remains unclear. Taking advantage of the large growth cone size of cultured primary neurons from pond snail Lymnaea stagnalis combined with dsRNA knockdown, we show that neuronal calcium sensor-1 (NCS-1) regulates neurite extension and branching, and activity-dependent Ca2+ signals in growth cones. An NCS-1 C-terminal peptide enhances only neurite branching and moderately reduces the Ca2+ signal in growth cones compared with dsRNA knockdown. Our findings suggest that at least two separate structural domains in NCS-1 independently regulate Ca2+ influx and neurite outgrowth, with the C-terminus specifically affecting branching. We describe a model in which NCS-1 regulates cytosolic Ca2+ around the optimal window level to differentially control neurite extension and branching.

The role of synaptotagmin I C2A calcium-binding domain in synaptic vesicle clustering during synapse formation

Synaptic vesicles aggregate at the presynaptic terminal during synapse formation via mechanisms that are poorly understood. Here we have investigated the role of the putative calcium sensor synaptotagmin I in vesicle aggregation during the formation of soma-soma synapses between identified partner cells using a simple in vitro synapse model in the mollusc Lymnaea stagnalis. Immunocytochemistry, optical imaging and electrophysiological recording techniques were used to monitor synapse formation and vesicle localization. Within 6 h, contact between appropriate synaptic partner cells up-regulated global synaptotagmin I expression, and induced a localized aggregation of synaptotagmin I at the contact site. Cell contacts between non-synaptic partner cells did not affect synaptotagmin I expression. Application of an human immunodeficiency virus type-1 transactivator (HIV-1 TAT)-tagged peptide corresponding to loop 3 of the synaptotagmin I C2A domain prevented synaptic vesicle aggregation and synapse formation. By contrast, a TAT-tagged peptide containing the calcium-binding motif of the C2B domain did not affect synaptic vesicle aggregation or synapse formation. Calcium imaging with Fura-2 demonstrated that TAT-C2 peptides did not alter either basal or evoked intracellular calcium levels. These results demonstrate that contact with an appropriate target cell is necessary to initiate synaptic vesicle aggregation during nascent synapse formation and that the initial aggregation of synaptic vesicles is dependent on loop 3 of the C2A domain of synaptotagmin I.