Thickening Of Alveolar Septa Research Articles

Progression of Pulmonary Emphysema and Continued Increase in Ectodomain Shedding of Cell Adhesion Molecule 1 After Cessation of Cigarette Smoke Exposure in Mice.

Pulmonary emphysema usually arises in cigarette smokers, and often progresses after smoking cessation and even in ex-smokers. Lung-epithelial cell adhesion molecule 1 (CADM1), an immunoglobulin superfamily member, is extracellularly shed to produce a proapoptotic C-terminal fragment (CTF) within the cell and contribute to the development of emphysema. Here, we made an ex-smoker model using C57BL/6 mice; mice (6-week-old; 5 mice per group) were exposed to passive smoke of eight cigarettes twice a day 5 days a week until 18 weeks of age, and were then left untreated until 30 weeks of age. We calculated the mean linear intercept (Lm) and the alveolar septal thickness in the lung histologic sections to estimate the alveolar space dilatation. At 18 weeks of age, Lm was marginally enlarged (P = 0.023) with a marked increase in the septal thickness (P < 0.001) in comparison with age-matched control mice (5 mice per group), while at 30 weeks, the increase in Lm was much more prominent (P = 0.006) and the septal thickness was normalized, suggesting that emphysema progressed with septal remodeling during smoking cessation. Western blot analyses of the lungs were performed for CADM1, a possible CADM1 sheddase ADAM10, an epithelial marker pan-cytokeratin, and a myofibroblastic marker α-smooth muscle actin to estimate the expression levels of CTF and ADAM10 per epithelial cell and the levels of pan-cytokeratin and αSMA per tissue. CADM1 shedding was increased in the treated mice than in control mice at both ages, in association with an increase in the CTF level at 30 weeks (P = 0.021). In total of the treated and control mice of 30 weeks of age, Lm was positively correlated with the CTF and ADAM10 levels, and pan-cytokeratin was negatively correlated with CTF, suggesting an involvement of CADM1 shedding in emphysema progression. Positive correlations were also found between CTF and ADAM10, and between ADAM10 and αSMA, suggesting that increased septal myofibroblasts might be involved in increased CADM1 shedding. Taken together, persisting increase in ectodomain shedding of CADM1 appeared to contribute to the progression of emphysema in ex-smokers, and might be accounted for by alveolar septal remodeling.

A Comparative Analysis of Saffron and Methylprednisolone on Bleomycin-Induced Pulmonary Fibrosis in Rats

Background: The purpose of this study was to compare the effects of saffron and methylprednisolone on bleomycin-induced pulmonary fibrosis in rats. Methods: This study was conducted in Bushehr, southern Iran in 2017.The animals were divided into four groups of five rats each. Three groups were injected with a single intratracheal dose of bleomycin (5 mg/kg). The fourth group was administered with normal saline at the same volume (200 µl). Saffron extract dissolved in water was given to one group (100 mg /body weight) orally while intraperitoneal injection of methylprednisolone (2.5 mg/kg) injected to another one for 16 days. The rats were sacrificed 28 days following surgery and their right and left lungs were removed and washed for measuring lung indices, myeloperoxidase activities and finally histopathological examination. Results: Injection of bleomycin caused decrement of body weight aggravated by intraperitoneal methylprednisolone treatment. Lung indices were increased in the bleomycin-treated group compared with the control, while methylprednisolone, unlike saffron, had no preventive effects on it. Both saffron and methylprednisolone treatment prevented the increase in lung myeloperoxidase as a destructive enzyme. In addition, excessive collagen deposition and thickening of alveolar septa were significantly prevented with saffron treatment as compared to methylprednisolone injection following hematoxylin and eosin staining. Conclusion: Saffron with established antioxidant properties could prevent some detrimental effects in bleomycin-induced pulmonary fibrosis even more than methylprednisolone injection known as a standard therapy in this murine model. More investigations must be carried out to examine the beneficial or harmful effects of this remedy.

Modulation of Myeloid Cell Recruitment and Activation By Alveolar Epithelial Type 2 Cells Drives Early Inflammation in a Murine Model of Mutant Surfactant Protein‐C Pulmonary Fibrosis

The missense isoleucine to threonine substitution at position 73 [I73T] in the Surfactant Protein‐C [SP‐C] gene [SFTPC], an alveolar type‐2 cell [AT2] restricted protein, has been linked to sporadic and familial cases of idiopathic pulmonary fibrosis (IPF). Many patients with idiopathic pulmonary fibrosis (IPF) experience one or more episodes of precipitous deterioration. These “acute exacerbations” are marked by altered gas exchange, neutrophilic/eosinophilic alveolitis, diffuse alveolar damage, and changes on HRCT. To temporally model the impact of SP‐CI73T expression on lung homeostasis, we generated an inducible SP‐CI73T expressing line (IER‐SP‐CI73T) by crossing a hypomorphic SP‐CI73T‐Neo founder line to a R26FlpOER line. Intraperitoneal tamoxifen administration to hypomorphic IER‐SP‐CI73T mice resulted in early increases in mutant sftpcI73T mRNA and proSP‐CI73T protein expression accompanied by allele and tamoxifen dose dependent weight loss and mortality. In this early phase (3–14 d), IER‐SP‐CI73T mice exhibited histological evidence of diffuse lung injury, increased vascular leak, elevations in total bronchoalveolar lavage (BAL) cell counts, and distinct temporal increases in BAL MCP‐1, IL‐5, Eotaxin, IL‐6, CCL‐17, KC/CXCL‐1 and TGF‐β. By 6 weeks, lungs of surviving IER‐SP‐CI73T mice showed marked alveolar septal thickening, diffuse collagen deposition, and foci of αSMA+ cells consistent with an IPF phenotype. RNA‐sequencing profiling and PCR analysis of AT2 cells from IER‐SP‐CI73T mice confirmed an epithelial contribution to these recruitment and activation factors starting at 3d. To test the downstream effects of AT2‐effector cell crosstalk, we analyzed BAL and whole lung digests via flow cytometry. Tamoxifen induction resulted in sequential accumulation of SiglecFloCD11b+CD64−CD11c−Ly6C+ monocytes (3d), LY6G+ neutrophils (7d) and SiglecFhiCD11bhiCD11clo eosinophils (2wk) in the lung. Conversely, there was significant reduction in the number of SiglecFhiCD11bintCD64hiCD11chiCD206hi resident macrophages in lung tissue digests of IER‐SP‐CI73T mice. Intratracheal and intravenous clodronate depletion was used to test the role of resident macrophages and infiltrating monocytes, respectively, in the development of the injury. Notably, early intratracheal clodronate administration was associated with enhanced mortality, corroborating the notion that resident alveolar macrophages are fundamental in the early inflammatory response and crosstalk with lung epithelia. Conversely, monocyte depletion via IV clodronate appeared to be beneficial with respect to survival and BAL cell counts at 3d and 7d suggesting a deleterious role for these proinflammatory infiltrating cells in SP‐CI73T mediated lung injury. Taken together, our findings support the concept that epithelial dysfunction is a key component of IPF and highlights the importance of AT2 crosstalk with immune compartments in the lung to mediate blood borne cell recruitment, as well as modulate the resultant acute exacerbations and fibrotic remodeling.This abstract is from the Experimental Biology 2018 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.

Oral exposure of deltamethrin and/or lipopolysaccharide (LPS) induced activation of the pulmonary immune system in Swiss albino mice

The deltamethrin, a synthetic pyrethroid, is used worldwide and has been linked with several type of acute toxicity. However, effect of low level of deltamethrin alone or in combination with the microbial antigen on pulmonary system is not understood. Lipopolysaccharide (LPS) was used as antigen which is a key inflammatory component of gram-negative bacteria, which induces a distinctive pattern of cytokine release that regulates inflammation. The aim was to determine whether chronic exposure to a low level of deltamethrin alone or in combination with LPS impair the lung response in adult male Swiss albino mice. The mice were orally exposed to different doses of deltamethrin (0.1, 0.05, 0.005, 0.001mg/kg bwt) and then immunized with LPS at the 60th day. None of the treatment groups contained residues of deltamethrin above the limits of quantification. Deltamethrin combined with LPS challenge caused significant lymphocytosis and neutropenia in group 1 (0.1mg/kg) mice (P < 0.05). The highest dose of deltamethrin exposure (0.1mg/kg bwt) alone altered the total cell count significantly in blood and total leukocyte count (TLC) and macrophage count in bronchoalveolar lavage fluid. Microscopic pulmonary damage was evaluated by H&E staining and EM which indicated that two higher doses of deltamethrin, i.e., 0.1 and 0.05mg/kg bwt, distinctly increased inflammatory cell infiltration and caused alveolar septa thickening and leukocyte infiltration into the alveolar septum (septal cell infiltration) in the lungs. Deltamethrin exposure alone and/or with endotoxin revealed different degrees of immunopositive reaction for Toll-like receptor 4 (TLR4) and pro-inflammatory cytokine-like tumor necrosis factor-alpha (TNFα) in different parts of the lungs. The expression of TLR4 and TNFα in the lung tissue was more pronounced in two higher dose groups. Thus, chronic low-level deltamethrin exposure may impair the main pro-inflammatory response in the lungs which is more pronounced in combination with LPS. Further research is required in direction of the mechanism of action of deltamethrin on the immune cell lineage and their differentiation.

Intratracheal Administration of Autologous Bone Marrow-Derived Cells Ameliorates Monocrotaline-Induced Pulmonary Vessel Remodeling and Lung Inflammation in Rats.

Inflammation is a feature of lung injury and plays a critical role in pulmonary vascular remodeling. Bone marrow-derived cells (BMCs) have anti-inflammatory properties and favor macrophage differentiation into an alternatively activated regulatory M2 profile. We investigated the effect of autologous BMCs on monocrotaline-induced pulmonary vessel remodeling and lung inflammation in rats, by direct administration into lungs via the airway. BMCs were isolated and plastic-adherent cells were cultured for 3weeks. 1week following monocrotaline (60mg/kg) treatment, fluorescently labeled autologous BMCs (1 × 106 cells) or vehicle were administered intratracheally to male Sprague-Dawley rats. 4weeks following monocrotaline treatment, lung pathology was evaluated. Monocrotaline increased pulmonary vessel wall thickness, perivascular infiltration, alveolar septal thickening, and inflammatory cell infiltration including T lymphocytes and monocytes/macrophages in alveolar areas, and also increased mRNA expression of inflammatory-related cytokines including IL-10 in the lung. Intratracheal administration of autologous BMCs prevented pulmonary vessel wall thickening and perivascular infiltration, and increased CD163-positive M2-like macrophages in perivascular areas. BMC administration inhibited the thickening of alveolar septa and reduced monocrotaline-induced inflammatory cell infiltration in lung parenchyma compared with monocrotaline-vehicle-treated-rats. Furthermore, BMCs administration increased expression of CD163-positive cells in perivascular areas and maintained the increased mRNA expression of IL-10. Intratracheal administration of autologous BMCs prevented monocrotaline-induced pulmonary vessel remodeling and lung inflammation, at least in part, through induction of alternatively activated macrophages and regulation of the local lung environment toward resolving inflammation.

SOX4 arrests lung development in rats with hyperoxia‑induced bronchopulmonary dysplasia by controlling EZH2 expression.

Bronchopulmonary dysplasia (BPD) is currently the most common severe complication in premature infants and is characterized by the arrest of alveolar and vascular growth. Alveolar type II cells play an important role in the pathological foundation of BPD. An association of BPD with epithelial-to-mesenchymal transition (EMT) in type II cells exposed to hyperoxia was previously identified. SOX4, a transcription factor that is indispensable to embryogenesis, including lung development, participates in regulating EMT and cell survival, affecting tumorigenesis. The aim of the present study was to investigate the involvement of SOX4 in the occurrence of BPD, which, to the best of our knowledge, has not been previously determined. For this purpose, newborn rats were randomly divided into two treatment groups: The model group was exposed to hyperoxia (80–85% O2), while the control group was kept under normoxic conditions (21% O2). Lung tissues were collected on postnatal days 1, 3, 7, 14 and 21 and morphological changes in the lungs were examined by hematoxylin and eosin staining. The location of SOX4 in type II cells was detected by double immunofluorescence. The expression of SOX4 and enhancer of zeste homolog 2 (EZH2) in type II cells and lung tissues were detected by immunochemistry, western blotting and quantitative polymerase chain reaction analysis. The results demonstrated that, compared with the control group, the radial alveolar count decreased rapidly in the model group, accompanied by increased mean alveolar diameter and alveolar septal thickness. SOX4 and EZH2 were highly expressed in type II cells exposed to hyperoxia. However, in total lung tissues, SOX4 and EZH2 expression was profoundly decreased in the early stages and increased in the late stages following exposure to hyperoxia. The expression of the EZH2 protein was positively correlated with that of the SOX4 protein. In conclusion, at the alveolar stage, which is a critical period after birth for lung development, hyperoxia induced dysregulation of SOX4 and EZH2 in rat lungs, indicating that SOX4 may contribute to the disruption of lung development in BPD by regulating EZH2 expression.

Structure-activity and anti-platelet aggregation mechanism of a non-toxic 5′-nucleotidase: Molecular docking and binding interaction study

Inflammation and oxidative stress are important risk factors in PM2.5-induced injury. The current study attempted to study the role of caspase recruitment domain (CARD) 9 in ambient PM2.5-induced pulmonary injury in mice. The CARD9−/− and C57BL/6 mice were exposed to 3.6, 7.8 and 15.6 mg/kg bw of PM2.5 or saline by intratracheal instillation. After the last PM2.5 exposure, the spleen, bronchoalveolar lavage fluid (BALF) and pulmonary tissue were collected and examined. The results showed that PM2.5 exposure induced inflammatory cell infiltration and alveolar septal thickening in the lung. Regulatory T (Treg) cells in spleen of CARD9−/− mice were significantly higher than that in the C57BL/6 mice, whereas the T helper cells 17 (Th17) were lower. The levels of interleukin (IL)-6 and IL-17A in BALF of the CARD9−/− mice were significantly lower than that in the C57BL/6 mice. The mRNA expression of IL-17A, IL-6 and RORγt in the lung of the CARD9−/− mice is significantly lower than that in the C57BL/6 mice, whereas the mRNA levels of Foxp3 in CARD9−/− mice were significantly higher than that in the C57BL/6 mice at the same dose of PM2.5. The protein expression of nuclear factor κB (NF-κB) is higher in the C57BL/6 mice than that in the CARD9−/− mice. This study indicates that ambient PM2.5-induced pulmonary injury is associated with the immune and inflammatory response. CARD9-mediated Th17/Treg differentiation probably played an important role in PM2.5-induced pulmonary damage.

Pneumocystis Jirovecii Pneumonia in Immunocompetent Japanese Male

SESSION TITLE: Unusual Pulmonary Infections SESSION TYPE: Global Case Report Poster PRESENTED ON: Tuesday, October 31, 2017 at 01:30 PM - 02:30 PM INTRODUCTION: Pneumocystis jiroveci pneumonia (PCP) is a common opportunistic infection in acquired immune deficiency syndrome (AIDS) patients. The risk factors are low CD4+ lymphocyte count (in HIV patients), underlying malignancies, organ transplantation or immunosuppressive medications. PCP without those risk factors is extremely rare. We herein report a case of PCP in an immunocompetent patient. CASE PRESENTATION: A 37-year-old Japanese male presented with a non-productive cough for two weeks. He had a history of intracerebral hemorrhage at the age of two. He had never smoked and drunk alcoholic beverages. Initial vital signs were almost unremarkable other than low oxygen saturation (93% in room air). Physical examinations were unremarkable. Chest radiograph revealed a diffuse airspace consolidation on the both lungs. Chest computed tomography (CT) scan revealed bilateral airspace consolidation, ground-glass opacity, and traction bronchiectasis on the upper lobes. Laboratory tests were remarkable for the elevated white blood cell (8,850/mm3), lactate dehydrogenase (425 U/l), C-reactive protein (9.18 mg/dl), KL-6 (2,940 U/ml), and decreased total protein (5.3 g/dl) and albumin (2.1 g/dl). Serum rheumatoid factor and anti-nuclear antibody were negative. Serum levels of immunoglobulin A, G and M were within normal range. Sputum and blood culture did not yield any organisms, and the patient underwent bronchoalveolar lavage (BAL) and transbronchial lung biopsy (TBLB). The cytological analysis of BAL fluid (BALF) was unremarkable, and routine cultures of BALF were negative. TBLB sample from the right upper lobe revealed alveolar septal thickening by chronic inflammatory cells infiltration with collagen-type fibrosis. From these results, the patient was diagnosed with acute exacerbation of chronic fibrosing interstitial pneumonia, and received intravenous levofloxacin with corticosteroid pulse therapy followed by a prednisolone maintenance therapy. On the 5th day of the treatment, his respiratory condition worsened and cyclophosphamide (500 mg/body) was added intravenously. On the same day, the additional laboratory examination revealed an elevated serum β-D glucan level (104.3 pg/ml), and voriconazole and sulfamethoxazole trimethoprim were started. The additional HIV antibody test was negative. Despite the anti-fungal therapy, he died on the 12th day due to respiratory failure. Autopsy revealed alveolar spaces filled with foamy amorphous material composed of abundant numbers of cystic forms of Pnemocystis jirovecii and cell debris, and also inflammatory reaction with hyaline membranes. Retrospectively, Gomori-Grocott’s methenamine silver-nitrate staining of the BALF and TBLB samples obtained on the admission day revealed a little amount of cystic forms of Pneumocystis jirovecii, therefore, it was thought that he had been PCP from the admission day. DISCUSSION: PCP in patients without underlying immunosuppressive diseases is exclusively rare, and to our best knowledge, only 19 cases have been reported to date. In Cano’s case series, two patients had previous or simultaneous infection by another microorganisms, and they speculated that a transitory alteration in the immunocompetency condition due to a previous or concomitant infection of PCP might develop. However, our patient did not show the evidence of infection other than Pneumocystis jirovecii. In our patient, we finally suspected PCP from the resistance immunosuppressive therapy and the elevated β-D glucan level, and it is thought that we should perform the Gomori-Grocott’s methenamine silver-nitrate staining of BALF, retrospectively. CONCLUSIONS: We experienced a case of PCP without any underlying risk factors. Although this condition is exclusively rare, but it may be necessary to perform serum β-D glucan assay and Gomori-Grocott’s methenamine silver-nitrate staining of BALF in patients with diffuse ground-glass opacity, regardless of immune status. Reference #1: Palella Jr FJ, Delaney KM, Moorman AC, et al. Declining morbidity and mortality among patients with advanced human immunodeficiency virus infection. New England Journal of Medicine. 1998;338(13):853-60. Reference #2: Jacobs JL, Libby DM, Winters RA, et al. A cluster of Pneumocystis carinii pneumonia in adults without predisposing illnesses. New England Journal of Medicine. 1991;324(4):246-50. Reference #3: Koshy G, Koshy JM, John M, Deodhar D. Pneumocystis jirovecii pneumonia in an immunocompetent host. Annals of Tropical Medicine and Public Health. 2015;8(4):122. DISCLOSURE: The following authors have nothing to disclose: Masanobu Okahisa, Kazunori Tobino No Product/Research Disclosure Information

Evaluation of potential changes in liver and lung tissue of rats in an ischemia-reperfusion injury model (modified pringle maneuver).

In surgical procedures involving the liver, such as transplantation, resection, and trauma, a temporary occlusion of hepatic vessels may be required. This study was designed to analyze the lesions promoted by ischemia and reperfusion injury of the hepatic pedicle, in the liver and lung, using histopathological and immunohistochemical techniques. In total, 39 Wistar rats were divided into four groups: control group (C n = 3) and ischemia groups subjected to 10, 20, and 30 minutes of hepatic pedicle clamping (I10, n = 12; I20, n = 12; I30, n = 12). Each ischemia group was subdivided into four subgroups of reperfusion (R15, n = 3; R30, n = 3; R60, n = 3; R120, n = 3), after 15, 30, 60, and 120 minutes of reperfusion, respectively. Significant differences were observed in the liver parenchyma (P < 0.05) between the values of microvesicles and hydropic degeneration at different times of ischemia and reperfusion. However, the values of vascular congestion, necrosis, and pyknotic nuclei showed no significant differences (P > 0.05). In the lung parenchyma, a significant difference was observed (P < 0.05) between the values of alveolar septal wall thickening and inflammatory infiltration at different times of ischemia and reperfusion. However, there was no significant difference (P < 0.05) between the values of vascular congestion, bronchial epithelial degeneration, interstitial edema, and hemorrhage. The positive immunoreactivity of caspase-3 protein in the liver parenchyma (indication of ongoing apoptosis), showed no significant differences (P > 0.05) at different times of ischemia and reperfusion. In the pulmonary parenchyma, the immunoreactivity was not specific, and was not quantified. This study demonstrated that the longer the duration of ischemia and reperfusion, the greater are the morphological lesions found in the hepatic and pulmonary parenchyma.

Aripiprazole-induced hypersensitivity pneumonitis

Aripiprazole is an atypical antipsychotic agent commonly used in the management of schizophrenia. Aripiprazole has not been reported to have an association with interstitial lung disease. We describe a case...

Soluble vimentin binds to P‐selectin and attenuates leukocytic infiltration into the lungs in murine endotoxin induced acute lung injury

BackgroundAcute lung injury (ALI) is a devastating condition that culminates as inflammation of the lungs mediated by leukocytic infiltration. In animal models, platelets and platelet P‐selectin are well described mediators of ALI and other forms of inflammation through enhancing capture and transmigration of neutrophils across vascular endothelium. Vimentin is an intermediate filament protein mainly thought to be involved in maintaining the cytoskeleton. Recently, there has been increasing evidence of vimentin's role during inflammation, although its precise role is unclear. We had recently observed that recombinant soluble vimentin (sVim) blocks neutrophil adhesion to platelets, endothelial cells, and P‐selectin monolayers; whether these observations translate into attenuation of ALI is unknown. Therefore, we hypothesize that soluble vimentin sVim blocks P‐selectin‐PSGL‐1 interactions and will decrease leukocytic infiltration into the lungs of endotoxin‐exposed mice.MethodsAll experiments were approved by the Institutional Animal Care and Use Committee at Baylor College of Medicine and the Michael E. DeBakey Veterans Affairs Medical Center. Recombinant sVim was expressed in E. coli and His‐purified using affinity chromatography. Binding kinetics of sVim to P‐selectin was determined using both enzyme‐linked immunosorbent assay (ELISA) and surface plasmon resonance (SPR). ELISA was performed by detecting sVim binding to immobilized P‐selectin/Fc or PSGL‐1/Fc protein. In SPR (BIACore), sVim was perfused over immobilized P‐selectin/Fc or IgG protein to determine the equilibrium dissociation constant KD. To determine whether sVim inhibits leukocytic infiltration into lungs after endotoxin exposure, C57BL/6 mice were treated with intraperitoneal injections of sVim (3 mg/kg) or vehicle control followed by endotoxin (O111:B4; 15 mg/kg) 1 hour later and then euthanized at 96 hours. Mice were evaluated by blinded investigators for both physical activity and degree of lung inflammation. Activity was determined using the mouse clinical assessment score for sepsis (M‐CASS) and lung inflammation was determined by alveolar septal thickening and leukocytic infiltration on hematoxylin and eosin stained sections.ResultssVim preferentially binds to P‐selectin/Fc and but not PSGL‐1/Fc in ELISA. Using SPR, sVim binds to P‐selectin/Fc with a KD of 125 ± 1.2 nM and not to IgG control. Endotoxin‐exposed mice treated with sVim were more active as determined by the M‐CASS (1.9 ± 0.2 vs 2.5 ± 0.2; 4‐point scale where lower is better; n=10/grp, p&lt;0.05). Mice receiving sVim also had less alveolar septal thickening and leukocytic infiltration into the lungs after exposure to endotoxin.ConclusionSoluble vimentin binds to P‐selectin and not P‐selectin glycoprotein ligand‐1 and decreases leukocytic infiltration into the lungs of endotoxin‐exposed mice. Further studies need to take place to determine whether vimentin also improves gas exchange in the lungs. Finally, dose‐response studies need to be performed to determine the optimal dose and timing of sVim to improve outcomes in acute lung injury.Support or Funding InformationNIH/NHLBI HL‐116524, NIH/NIGMS GM‐112806

Effects of Long-Term Simulated Microgravity on Oxidant and Antioxidant Values in the Plasma and Lung Tissues of Rhesus Macaque

This study evaluated the influence of long-term simulated microgravity on oxidative stress and total antioxidant capacity in the plasma and lung tissues of rhesus macaque (-10°C head-down tilting). Fifteen healthy male rhesus macaques were randomly divided into groups 1 (control, n=5), groups 2 (head-down tilting for 6 weeks, n=5) and groups 3 (head-down tilting for 6 weeks and recover from 4 weeks, n=5). Oxidative stress was evaluated by critical SOD, GSH, H2O2 in plasma and SOD, GSH in lung tissues. HE staining was used to observe the histopathological structure changes of pulmonary tissues. CAT, SOD1, SOD2, SOD3, GPX1, GPX4, GPX7, PRDX1, HMOX1, ALOX5 and DUOX1 mRNA were measured by real-time PCR. GSH concentration was significantly decreased, whereas H2O2 level was significantly increased in group 2 compared with group 1 and group 3. Compared to group 1, histopathological examination revealed alveolar septal thickening, and alveolar and interstitial lymphocytic infiltration in group 2 and group 3 and the pathological changes in group 3 were smaller than those in group 2. Group 2 and group 3 showed significant up-regulation of SOD3 gene compared with group 1 by real-time PCR. In a long-term simulated microgravity environment, systemic antioxidant level of GSH was reduced but an oxidative stress marker of H2O2 was increased. Meanwhile, long-term simulated microgravity caused lung injury and induced the mRNA of SOD3 expression in lung tissues. But oxidant stress is not a major factor involved in the development of lung damage under simulated microgravity. Further study still clarifies the mechanism about the lung injury under microgravity.

Stereological monitoring of mouse lung alveolarization from the early postnatal period to adulthood.

Postnatal lung maturation generates a large number of small alveoli, with concomitant thinning of alveolar septal walls, generating a large gas exchange surface area but minimizing the distance traversed by the gases. This demand for a large and thin gas exchange surface area is not met in disorders of lung development, such as bronchopulmonary dysplasia (BPD) histopathologically characterized by fewer, larger alveoli and thickened alveolar septal walls. Diseases such as BPD are often modeled in the laboratory mouse to better understand disease pathogenesis or to develop new interventional approaches. To date, there have been no stereology-based longitudinal studies on postnatal mouse lung development that report dynamic changes in alveoli number or alveolar septal wall thickness during lung maturation. To this end, changes in lung structure were quantified over the first 22 mo of postnatal life of C57BL/6J mice. Alveolar density peaked at postnatal day (P)39 and remained unchanged at 9 mo (P274) but was reduced by 22 mo (P669). Alveoli continued to be generated, initially at an accelerated rate between P5 and P14, and at a slower rate thereafter. Between P274 and P669, loss of alveoli was noted, without any reduction in lung volume. A progressive thinning of the alveolar septal wall was noted between P5 and P28. Pronounced sex differences were observed in alveoli number in adult (but not juvenile) mice, when comparing male and female mouse lungs. This sex difference was attributed exclusively to the larger volume of male mouse lungs.

CARD9-mediated ambient PM2.5-induced pulmonary injury is associated with Th17 cell

Inflammation and oxidative stress are important risk factors in PM2.5-induced injury. The current study attempted to study the role of caspase recruitment domain (CARD) 9 in ambient PM2.5-induced pulmonary injury in mice. The CARD9−/− and C57BL/6 mice were exposed to 3.6, 7.8 and 15.6mg/kgbw of PM2.5 or saline by intratracheal instillation. After the last PM2.5 exposure, the spleen, bronchoalveolar lavage fluid (BALF) and pulmonary tissue were collected and examined. The results showed that PM2.5 exposure induced inflammatory cell infiltration and alveolar septal thickening in the lung. Regulatory T (Treg) cells in spleen of CARD9−/− mice were significantly higher than that in the C57BL/6 mice, whereas the T helper cells 17 (Th17) were lower. The levels of interleukin (IL)-6 and IL-17A in BALF of the CARD9−/− mice were significantly lower than that in the C57BL/6 mice. The mRNA expression of IL-17A, IL-6 and RORγt in the lung of the CARD9−/− mice is significantly lower than that in the C57BL/6 mice, whereas the mRNA levels of Foxp3 in CARD9−/− mice were significantly higher than that in the C57BL/6 mice at the same dose of PM2.5. The protein expression of nuclear factor κB (NF-κB) is higher in the C57BL/6 mice than that in the CARD9−/− mice. This study indicates that ambient PM2.5-induced pulmonary injury is associated with the immune and inflammatory response. CARD9-mediated Th17/Treg differentiation probably played an important role in PM2.5-induced pulmonary damage.

Study on the expression of epidermal growth factor receptor protein during benzo(a)pyrene induced carcinogenesis

Objective: To explore the expression of epidermal growth factor receptor(EGFR) protein during benzo(a)pyrene (BaP) induced carcinogenesis. Methods: This study, we firstly utilized immunofluorescence assay and Western-blot to examine EGFR expression of the BaP which was constructed previously by project team induced malignant transformation human bronchial epithelial cell (BTC) and the control (16HBE cell). Then, we selected 36 healthy SD rats, divided into two groups according to simple random method, 18 rats each group. The constructed rat lung neoplasm model induced by pulmonary injection of BaP (10 mg/ml of BaP solution in 0.2 ml corn oil), contrast group use 0.2 ml corn oil, lung tissue was collected and the EGFR expression of lung tissue was detected by immunofluorescence assay and Western blot. T analysis was used to test the different of EGFR between two groups. Results: Immunofluorescence analysis showed that the EGFR expression in BTC was significantly higher than 16HBE cell. Meanwhile, Western blot also was used to confirmed this result, the relative expression of EGFR protein in the rats of the model group the control group were 1.04±0.13 and 2.32±0.12, respectively, and the difference was statistically significance (t=12.39, P<0.001). In vivo, well-defined tumor was found in the rat with pulmonary injection of BaP, and the lung showed diffuse alveolar septal thickening, alveolar wall destruction and pulmonary alveoli fusion, which suggested that the rat lung neoplasm model was constructive successfully. Furthermore, we found the EGFR expression of lung was increased dramatically in the rat lung neoplasm model by immunofluorescence detection and Western blot. The relative expression of EGFR protein in the rats of the model group the control group were 0.21±0.03 and 1.30±0.07, respectively, and the difference was statistically significance (t=12.84, P<0.001). Conclusion: Expression of EGFR protein was increased during BaP carcinogenesis, and EGFR may play an important role in the carcinogenesis of BaP.

Molecular mechanisms of pulmonary response progression in crystalline silica exposed rats

An understanding of the mechanisms underlying diseases is critical for their prevention. Excessive exposure to crystalline silica is a risk factor for silicosis, a potentially fatal pulmonary disease. Male Fischer 344 rats were exposed by inhalation to crystalline silica (15 mg/m3, six hours/day, five days) and pulmonary response was determined at 44 weeks following termination of silica exposure. Additionally, global gene expression profiling in lungs and BAL cells and bioinformatic analysis of the gene expression data were done to understand the molecular mechanisms underlying the progression of pulmonary response to silica. A significant increase in lactate dehydrogenase activity and albumin content in BAL fluid (BALF) suggested silica-induced pulmonary toxicity in the rats. A significant increase in the number of alveolar macrophages and infiltrating neutrophils in the lungs and elevation in monocyte chemoattractant protein-1 (MCP-1) in BALF suggested the induction of pulmonary inflammation in the silica exposed rats. Histological changes in the lungs included granuloma formation, type II pneumocyte hyperplasia, thickening of alveolar septa and positive response to Masson’s trichrome stain. Microarray analysis of global gene expression detected 94 and 225 significantly differentially expressed genes in the lungs and BAL cells, respectively. Bioinformatic analysis of the gene expression data identified significant enrichment of several disease and biological function categories and canonical pathways related to pulmonary toxicity, especially inflammation. Taken together, these data suggested the involvement of chronic inflammation as a mechanism underlying the progression of pulmonary response to exposure of rats to crystalline silica at 44 weeks following termination of exposure.

Effects of Long-Term Simulated Microgravity on Oxidant and Antioxidant Values in the Plasma and Lung Tissues of Rhesus Macaque

This study evaluated the influence of long-term simulated microgravity on oxidative stress and total antioxidant capacity in the plasma and lung tissues of rhesus macaque (-10℃ head-down tilting). Fifteen healthy male rhesus macaques were randomly divided into groups 1 (control, n=5), groups 2 (head-down tilting for 6 weeks, n=5) and groups 3 (head-down tilting for 6 weeks and recover from 4 weeks, n=5). Oxidative stress was evaluated by critical SOD, GSH, H₂O₂ in plasma and SOD, GSH in lung tissues. HE staining was used to observe the histopathological structure changes of pulmonary tissues. CAT, SOD1, SOD2, SOD3, GPX1, GPX4, GPX7, PRDX1, HMOX1, ALOX5 and DUOX1 mRNA were measured by real-time PCR. GSH concentration was significantly decreased, whereas H2O2 level was significantly increased in group 2 compared with group 1 and group 3. Compared to group 1, histopathological examination revealed alveolar septal thickening, and alveolar and interstitial lymphocytic infiltration in group 2 and group 3 and the pathological changes in group 3 were smaller than those in group 2. Group 2 and group 3 showed significant up-regulation of SOD3 gene compared with group 1 by real-time PCR. In a long-term simulated microgravity environment, systemic antioxidant level of GSH was reduced but an oxidative stress marker of H₂O₂ was increased. Meanwhile, long-term simulated microgravity caused lung injury and induced the mRNA of SOD3 expression in lung tissues. But oxidant stress is not a major factor involved in the development of lung damage under simulated microgravity. Further study still clarifies the mechanism about the lung injury under microgravity.

Antithrombin III improved neutrophil extracellular traps in lung after the onset of endotoxemia

BackgroundCoagulation and inflammation are closely linked during acute inflammatory conditions, such as sepsis. Antithrombin (AT) is an anticoagulant that also has anti-inflammatory activities. The effects of therapeutically administering AT III after the onset of endotoxemia or sepsis were not clear. Here, we studied the effects of administering AT III after inducing lethal endotoxemia in mice. MethodsMice were injected intraperitoneally with lipopolysaccharide (LPS) to induce endotoxemia. AT III was administered 3 h later. We assessed survival and the severity of endotoxemia and quantified plasma cytokine levels and biochemical markers of liver and kidney function. In the lungs, we examined neutrophil accumulation, neutrophil extracellular traps, alveolar wall thickness, and chemokine (C-X-C motif) ligand 1 (cxcl-1), cxcl-2, and high mobility group box 1 expression. ResultsAdministering AT III reduced the severity and mortality of LPS-induced endotoxemia as indicated by 24-h survival of 84% of the mice that received LPS + AT III and only 53% of mice given LPS alone (P < 0.05). AT III treatment attenuated several changes induced in the lungs by endotoxemia including cxcl-2 mRNA expression, high mobility group box 1 protein expression, neutrophil accumulation, alveolar septal thickening, and neutrophil extracellular trap formation. AT III did not decrease plasma cytokine levels or plasma urea nitrogen levels that were upregulated as a result of LPS-induced endotoxemia. ConclusionsAdministration of AT III after the onset of endotoxemia improved outcomes in a mouse model. The attenuation of lung inflammation may have a large impact on mortality and morbidity. Because lung inflammation increases the likelihood of mortality from sepsis, AT III could be a useful agent in septic patients.

Consequences of a Maternal High-Fat Diet and Late Gestation Diabetes on the Developing Rat Lung.

RationaleInfants born to diabetic or obese mothers are at risk of respiratory distress and persistent pulmonary hypertension of the newborn (PPHN), conceivably through fuel-mediated pathogenic mechanisms. Prior research and preventative measures focus on controlling maternal hyperglycemia, but growing evidence suggests a role for additional circulating fuels including lipids. Little is known about the individual or additive effects of a maternal high-fat diet on fetal lung development.ObjectiveThe objective of this study was to determine the effects of a maternal high-fat diet, alone and alongside late-gestation diabetes, on lung alveologenesis and vasculogenesis, as well as to ascertain if consequences persist beyond the perinatal period.MethodsA rat model was used to study lung development in offspring from control, diabetes-exposed, high-fat diet-exposed and combination-exposed pregnancies via morphometric, histologic (alveolarization and vasculogenesis) and physiologic (echocardiography, pulmonary function) analyses at birth and 3 weeks of age. Outcomes were interrogated for diet, diabetes and interaction effect using ANOVA with significance set at p≤0.05. Findings prompted additional mechanistic inquiry of key molecular pathways.ResultsOffspring exposed to maternal diabetes or high-fat diet, alone and in combination, had smaller lungs and larger hearts at birth. High-fat diet-exposed, but not diabetes-exposed offspring, had a higher perinatal death rate and echocardiographic evidence of PPHN at birth. Alveolar mean linear intercept, septal thickness, and airspace area (D2) were not significantly different between the groups; however, markers of lung maturity were. Both diabetes-exposed and diet-exposed offspring expressed more T1α protein, a marker of type I cells. Diet-exposed newborn pups expressed less surfactant protein B and had fewer pulmonary vessels enumerated. Mechanistic inquiry revealed alterations in AKT activation, higher endothelin-1 expression, and an impaired Txnip/VEGF pathway that are important for vessel growth and migration. After 3 weeks, mortality remained highest and static lung compliance and hysteresis were lowest in combination-exposed offspring.ConclusionThis study emphasizes the effects of a maternal high-fat diet, especially alongside late-gestation diabetes, on pulmonary vasculogenesis, demonstrates adverse consequences beyond the perinatal period and directs attention to mechanistic pathways of interest. Findings provide a foundation for additional investigation of preventative and therapeutic strategies aimed at decreasing pulmonary morbidity in at-risk infants.

Reproducibility of quantitative indices of lung function and microstructure from 129 Xe chemical shift saturation recovery (CSSR) MR spectroscopy.

PurposeTo evaluate the reproducibility of indices of lung microstructure and function derived from 129Xe chemical shift saturation recovery (CSSR) spectroscopy in healthy volunteers and patients with chronic obstructive pulmonary disease (COPD), and to study the sensitivity of CSSR‐derived parameters to pulse sequence design and lung inflation level.MethodsPreliminary data were collected from five volunteers on three occasions, using two implementations of the CSSR sequence. Separately, three volunteers each underwent CSSR at three different lung inflation levels. After analysis of these preliminary data, five COPD patients were scanned on three separate days, and nine age‐matched volunteers were scanned three times on one day, to assess reproducibility.ResultsCSSR‐derived alveolar septal thickness (ST) and surface‐area‐to‐volume (S/V) ratio values decreased with lung inflation level (P < 0.001; P = 0.057, respectively). Intra‐subject standard deviations of ST were lower than the previously measured differences between volunteers and subjects with interstitial lung disease. The mean coefficient of variation (CV) values of ST were 3.9 ± 1.9% and 6.0 ± 4.5% in volunteers and COPD patients, respectively, similar to CV values for whole‐lung carbon monoxide diffusing capacity. The mean CV of S/V in volunteers and patients was 14.1 ± 8.0% and 18.0 ± 19.3%, respectively.Conclusion 129Xe CSSR presents a reproducible method for estimation of alveolar septal thickness. Magn Reson Med 77:2107–2113, 2017. © 2016 The Authors Magnetic Resonance in Medicine published by Wiley Periodicals, Inc. on behalf of International Society for Magnetic Resonance in Medicine. This is an open access article under the terms of the Creative Commons Attribution License, which permits use, distribution and reproduction in any medium, provided the original work is properly cited.