Background and Purpose Serum amyloid A (SAA), an acute-phase protein whose level tracks infection and inflammation, is the precursor protein of amyloid A (AA) fibrils that is thought to cause AA amyloidosis in human and animals. SAA protein has several isoforms based on the difference of amino acid sequence, such as SAA1 to SAA4 in mice. AA fibrils are associated with chronic inflammation and are mainly originated from SAA1 produced in the liver. SAA3 reportedly contributes to the innate immune response in epithelia; however, little is known about its role at the lung epithelia. Therefore, we investigated SAA3 expression in the lung epithelium activated by bacterial antigens. Materials and Methods The expressions of SAA3 and SAA1 mRNA were investigated using quantitative real-time PCR, in vitro using mouse Clara (Club) cells and ex vivo using surgically removed mouse lungs, after their stimulation by using either lipopolysaccharide (LPS), the major outer membranous antigen of gram-negative bacteria, or lipoteichoic acid (LTA), the major outer membranous antigen of gram-positive bacteria. In addition, SAA3 and SAA1/2 proteins in treated lung samples were detected by immunohistochemistry (IHC). Results SAA3 mRNA expression increased in cells and lungs treated with either LPS or LTA. SAA3 mRNA was more sensitively expressed in LPS than LTA treatment. In contrast, SAA1 mRNA expression did not increase by either LPS or LTA treatment. Furthermore, SAA3 mRNA expression increased in a dose-dependent manner in cells treated with tumor necrosis factor-alpha. By IHC, SAA3 protein was highly expressed in the luminal side of the bronchial epithelium, while SAA1/2 was not expressed. Conclusion These results obtained from in vitro and ex vivo experiments suggest that SAA3 plays an important role in the innate immune response to bacterial infection in the lung epithelia.

Purpose/Aim: Pulmonary fibrosis (PF) is characterized by the progressive and ultimately fatal accumulation of fibroblasts and extracellular matrix in the lung that distorts its architecture and compromises its function.Objective: The present study investigated the potential protective effects of schisandrin B (Sch B) on the Wingless/Integrase-1 (Wnt) signaling pathway in attenuating inflammation and oxidative stress in ICR mice.Methods: Sixty healthy ICR mice were randomly divided into the following groups: control group, bleomycin (BLM) group, Sch B low dose (Sch B-L) group, Sch B medium dose (Sch B-M) group, Sch B high dose (Sch B-H) group, and dexamethasone (DXM) group. The expression of transforming growth factor (TGF)-β1 was examined by ELISA. In addition, the levels of superoxide dismutase (SOD), hydroxyproline (HYP), and the total antioxidant capacity (T-AOC) were determined. The protein and mRNA levels of matrix metalloproteinase 7 (MMP7) and β-catenin in mice were analyzed by western blot and quantitative real -quantitative time PCR (qRT-PCR), respectively.Results: Lung tissues from the BLM group exhibited significantly more inflammatory changes and a significantly greater number of collagen fibers than lung tissues from the control group. In addition, the lung tissues from these BLM-treated mice exhibited slightly increased MMP7 and β-catenin protein expression. Lung tissues from the Sch B-H group exhibited fewer inflammatory changes and fewer collagen fibers than lung tissues from the BLM group. Furthermore, the lung tissues from the Sch B-H mice exhibited decreased HYP and TGF-β1 levels, but increased SOD and T-AOC levels.Conclusions: The present study provided evidence that Sch B may be a potential therapeutic agent for the treatment of PF.

Multiple pharmacological interventions tested over the last decades have failed to reduce ARDS mortality. This short note recounts past data indicating that (i) neutrophils home along an IL-8 gradient, (ii) in ARDS, massive neutrophil accumulation and degranulation in and along bronchoalveolar spaces contributes to damage and hypoxia, (iii) large increases in IL-8 are one of the chemotaxic signals drawing neutrophils to the ARDS lung, and (iv) old data from dermatology and glioblastoma research showed that the old drug against Hansen’s disease, dapsone, inhibits neutrophils’ chemotaxis to IL-8. Therefore dapsone might lower neutrophils’ contributions to ARDS lung pathology. Dapsone can create methemoglobinemia that although rarely problematic it would be particularly undesirable in ARDS. The common antacid drug cimetidine lowers risk of dapsone related methemoglobinemia and should be given concomitantly.

Background: The axis formed by CXC chemokine receptor 4 (CXCR4), expressed on mesenchymal stromal cells (MSCs), and stromal cell-derived factor-1 (SDF-1), expressed in recipient organs, is a critical mediator of MSC migration in non-pulmonary injury models. The role and regulation of SDF-1 expression in preterm lungs, of potential relevance for MSC-based cell therapy for bronchopulmonary dysplasia (BPD), is unknown. The aim of this study was to determine the spatiotemporal pattern of CXCR4/SDF-1 expression in lungs of extremely preterm infants at risk for BPD.Methods: Postmortem lung samples were collected from ventilated extremely preterm infants who died between 23 and 29 wks (“short-term ventilated”) or between 36 and 39 wks (“long-term ventilated”) corrected postmenstrual age. Results were compared with age-matched infants who had lived <12 h or stillborn infants (“early” and “late” controls). CXCR4 and SDF-1 expression was studied by immunohistochemistry, immunofluorescence/confocal microscopy, and qRT-PCR analysis.Results: Compared with age-matched controls without antenatal infection, lungs of early control infants with evidence of intrauterine infection/inflammation showed significant upregulation of SDF-1 expression, localized to the respiratory epithelium, and of CXCR4 expression, localized to stromal cells. Similarly, pulmonary SDF-1 mRNA levels were significantly higher in long-term ventilated ex-premature infants with established BPD than in age-matched controls. The pulmonary vasculature was devoid of SDF-1 expression at all time points. Endogenous CXCR4-positive stromal cells were preferentially localized along the basal aspect of SDF-1-positive bronchial and respiratory epithelial cells, suggestive of functionality of the CXCR4/SDF-1 axis.Conclusions: Incipient and established neonatal lung injury is associated with upregulation of SDF-1 expression, restricted to the respiratory epithelium. Knowledge of the clinical associations, time-course and localization of pulmonary SDF-1 expression may guide decisions about the optimal timing and delivery route of MSC-based cell therapy for BPD.

Purpose: Airway remodeling is one of the features of severe asthma. Previous study shows that IL-27 inhibits airway inflammation in asthmatic mice. However, the role of IL-27 on airway remodeling in OVA-induced asthmatic mice and its possible mechanism remain unclear. Methods: We established an ovalbumin (OVA)-induced asthmatic mice model. IL-27 were preventative administered to OVA-induced asthmatic mice. The total cells in Bronchoalveolar lavage fluid (BALF) and Airway hyperresponsiveness (AHR) were measured. The lung tissues were performed by Hematoxylin and eosin (HE) staining to estimate the pathological changes. Masson staining was used to observe the collagen deposition area. The expression of α-smooth muscle actin (α-SMA) and Type I collagen was measured by immunohistochemistry, western blot, and quantitative reverse transcription polymerase chain reaction (qRT-PCR). Additionally, western blot was also used to measure the expression of phosphorylated-Akt (p-Akt) in each group. Results: IL-27 group showed significant inhibitory effect on the α-SMA and Type I collagen. The expression of p-Akt in the tissues of asthma model was increased and inhibited by IL-27. Conclusions: IL-27 can alleviate airway remodeling in OVA-induced asthmatic mice, and the mechanism may relate to PI3K/Akt pathway.

Purpose/Aim of the study: Prolonged exposure to hyperoxia can cause injury to normal lung tissue. However, patients with acute hypoxic respiratory failure are frequently exposed to very high oxygen levels. This study investigated the effects of long term normobaric hyperoxia exposure in a mouse model of acute severe lung injury (SLI).Meterials and Methods: C57BL/6J mice were injected intratracheally with lipopolysaccharide (LPS, 4 mg/kg) to induce acute lung injury. After 2 h, mice were divided into two groups, and then exposed to room air or hyperoxic conditions for 48 h. Animals in the hyperoxia group were placed within their cages in a Plexiglass chamber with an atmosphere of 95% O2 maintained constant using an oxygen analyzer. After exposure to normoxia (N) or hyperoxia (H) for 48 h, the left lungs were collected for tissue paraffin block or oxidative stress assay. One lobe of the right lung was collected for lung/body weight ratio. The lung injury score and the mean linear intercept were evaluated in hematoxylin and eosin -stained lungs. The biochemical tests were performed by using ELISA assay.Results: Lung injury scoring, lung/body weight, and mean linear intercept were not significantly different between the N + LPS (NLPS) and H + LPS (HLPS) groups. Similar trends were observed in hydroxyproline and transforming growth factor-β (TGF-β) levels. Total cell and neutrophil counts in bronchoalveolar lavage fluid showed no significant differences between NLPS and HLPS groups. Histological analyses demonstrated more severe lung injury and fibrosis in the NLPS group than in the HLPS group. In addition, interleukin (IL)-1β was significantly decreased in the HLPS group compared to the NLPS group. Other inflammatory cytokines, such as tumor necrosis factor-α (TNF-α) and IL-6, showed similar trends. The malondialdehyde (MDA) level was significantly lower in the HLPS group than in the NLPS group.Conclusions: Exposure to hyperoxia did not augment lung injury in the LPS-induced lung injury model, and some indicators even showed better outcomes. These results suggest that long-term high-oxygen therapy in patients with SLI has low risk of lung injury.

Background and purpose of the study: Pseudomonas aeruginosa commonly colonizes the airway of patients with chronic obstructive pulmonary disease (COPD) and exacerbates their symptoms. P. aeruginosa carries flagellin that stimulates toll-like receptor (TLR)-5; however, the role of flagellin in the pathogenesis of COPD remains unclear. The aim of the study was to evaluate the mechanisms of the flagellin-induced innate immune response in bronchial epithelial cells, and to assess the effects of anti-inflammatory agents for treatment. Materials and methods: We stimulated BEAS-2B cells with P. aeruginosa-derived flagellin, and assessed mRNA expression and protein secretion of interleukin (IL)-6 and IL-8. We also used mitogen-activated protein kinases (MAPK) inhibitors to assess the signaling pathways involved in flagellin stimulation, and investigated the effect of clinically available anti-inflammatory agents against flagellin-induced inflammation. Results: Flagellin promoted protein and mRNA expression of IL-6 and IL-8 in BEAS-2B cells and induced phosphorylation of p38, ERK, and JNK; p38 phosphorylation-induced IL-6 production, while IL-8 production resulted from p38 and ERK phosphorylation. Fluticasone propionate (FP) and dexamethasone (DEX) suppressed IL-6 and IL-8 production in BEAS-2B cells, but clarithromycin (CAM) failed to do so. Conclusions: P. aeruginosa-derived flagellin-induced IL-6 and IL-8 production in bronchial epithelial cells, which partially explains the mechanisms of progression and exacerbation of COPD. Corticosteroids are the most effective treatment for the suppression of flagellin-induced IL-6 and IL-8 production in the bronchial epithelial cells.

Aims: Cough is a common medical problem, and when it persists for more than 8 weeks it is arbitrarily defined as chronic. While spirometry assesses the large airways, impulse oscillometry system (IOS) measures peripheral airway function. The present study investigated whether provocation with inhaled capsaicin affects the large and small airways in patients with chronic idiopathic cough (CIC) or asthma and in healthy controls. Materials and methods: Twenty-one patients with CIC, 18 patients with asthma, and 22 healthy controls were subjected to a provocation with capsaicin, and lung function was assessed by IOS and spirometry. Results: At baseline, before the capsaicin provocation, the CIC group had significantly increased airway resistance compared to the controls. After capsaicin provocation, the CIC group exhibited a significant increase in total airway resistance. The asthma group showed a small but significant reduction in spirometry, increased airway resistance, and reactance after capsaicin provocation. Capsaicin inhalation affected neither the spirometry nor the IOS of the healthy controls. Conclusions: The present study demonstrates that inhaled capsaicin induces changes in lung function, both in patients with CIC and in patients with asthma, when IOS, which measures changes also in the peripheral airways, is used. IOS appears to be a more sensitive tool than spirometry for the detection of airway impairment in airway provocation studies. In patients with CIC, higher peripheral resistance at baseline may have clinical significance.

Objective: We aimed to determine whether beryllium toxicity was associated with mitochondria apoptosis pathway in SD rats. Methods: Thirty-two SD rats were given an intratracheal instillation dose of 10 g/l beryllium oxide (0.5 ml per rat). Additional 32 rats were given an intratracheal instillation dose of 0.9% normal saline (0.5 ml per rat). The percentage of apoptosis, mitochondrial membrane potential, the expression level of apoptosis related genes and proteins, including bcl2, Bax and Caspase-3 were detected. Results: The average of percentage of apoptosis, the expression of caspase-3, bax, and cytochrome c were decreased significantly in lung tissues from rats exposed to beryllium oxide compared to normal controls. The expression of bcl2 and ADP were increased significantly at 80 d after exposure. Conclusions: We conclude that inhibition of apoptosis by beryllium oxide involves mitochondrial apoptosis pathway in rat model of beryllium oxide-induced pulmonary disease.

Aim of this study: Airway remodeling, which encompasses structural changes in airway is a main feature of asthma. Interleukin-33 (IL-33) has been reported to be a vital cytokine in airway remodeling in asthma, but the underlying mechanisms are not clear yet. This study focused on discussing the role of IL-33 in airway remodeling in asthma. Material and methods: Female BALB/c mice were divided into a control group, an OVA induced allergic airway disease group and an anti-ST2 antibody intervention group. Immunohistochemistry and western blot were performed to detect IL-33, ST2 expression in addition to airway remodeling markers a-smooth muscle actin (a-SMA) and type 1 collagen in OVA-induced mice model. Levels of p-JNK and p-STAT3 activation in mice were detected by western blot. Human lung fibroblast (HLF) were stimulated with rhIL-33, anti-ST2 antibody and JNK inhibitor sp600125 and levels of JNK and STAT3 activation were determined via western blot and immunofluorescence staining. Results: Anti-ST2 treatment inhibited JNK/STAT3 phosphorylation and airway remodeling in OVA-induced mouse model. IL-33 induced a-SMA and collagen 1 expression was inhibited by anti-ST2 antibody and sp600125 treatment via decreased JNK/STAT3 phosphorylation in human lung fibroblast. Conclusions: IL-33 promoted airway remodeling by interacting with ST2 to activate the JNK/STAT3 signaling pathway in asthma.