Effect of subchronic in vivo exposure to nitrogen dioxide on lung tissue inflammation, airway microvascular leakage, and in vitro bronchial muscle responsiveness in rats.

In the present study we asked if surfactant metabolism was altered in surfactant protein (SP) A-deficient mice in vivo. Although previous studies in vitro demonstrated that SP-A modulates surfactant secretion and reuptake by type II cells, mice made SP-A deficient by homologous recombination grow and reproduce normally and have normal lung function. Alveolar and lung tissue saturated phophatidylcholine (Sat PC) pools were 50 and 26% larger, respectively, in SP-A(-/-) mice than in SP-A(+/+) mice. Radiolabeled choline and palmitate incorporation into lung Sat PC was similar both in vivo and for lung tissue slices in vitro from SP-A(+/+) and SP-A(-/-) mice. Percent secretion of radiolabeled Sat PC was unchanged from 3 to 15 h, although SP-A(-/-) mice retained more labeled Sat PC in the alveolar lavages at 48 h (consistent with the increased surfactant pool sizes). Clearance of radiolabeled dipalmitoylphosphatidylcholine and SP-B from the air spaces after intratracheal injection was similar in SP-A(-/-) and SP-A(+/+) mice. Lack of SP-A had minimal effects on the overall metabolism of Sat PC or SP-B in mice.

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Methylprednisolone Protects SAP and Pancreatitis-Associated ALI in Mice by Inhibiting NLRP3 Inflammasome Through NF-κB

10.21203/rs.3.rs-96231/v1 ◽

2020 ◽

Author(s):

Chuan-jiang Liu ◽

Qiang Fu ◽

Wenjing Zhou ◽

Xu Zhang ◽

Rui Chen ◽

...

Keyword(s):

Lung Tissue ◽

Nlrp3 Inflammasome ◽

Antioxidant Properties ◽

Underlying Mechanism ◽

Peritoneal Macrophages ◽

Dependent Manner ◽

Expression Levels ◽

Tnf Α

Abstract Background: Methylprednisolone (MP) is a synthetic corticosteroid with potent anti-inflammatory and antioxidant properties used as therapy for a variety of diseases. The underlying mechanism of MP to reduce acute pancreatitis still needs to be elucidated.Methods: Twenty-four male C57BL/6 mice (6-8 weeks) were used to establish SAP mouse model by administering an intraperitoneal injection of Cae and LPS. Amylase expression levels of serum and PLF were measured with an amylase assay kit. The concentrations of IL-1β and TNF-α in the serum and PLF were detected by ELISA. The level of pancreatic and lung tissue damage and inflammation was assessed by H&E staining and immunofluorescence staining. Western blot and qPCR were used to detect the expression levels of NLRP3, IL-1β and TNF-αin vivo and in vitro.Results: In this study, we found MP, used in the early phase of SAP, decreased the levels of IL-1β and TNF-α in serum and peritoneal lavage fluids (PLF), reduced the level of serum amylase and the expression of MPO in lung tissue, attenuated the pathological injury of the pancreas and lungs in a dose-dependent manner. The expression of NLRP3 and IL-1β in pancreas and lungs was down-regulated significantly depending on the MP concentration. In vitro, MP reduced the levels of IL-1β and TNF-α by down-regulating the expression of NLRP3, IL-1β and p-NF-κB in isolated peritoneal macrophages. Conclusion: MP can attenuate the injury of pancreas and lungs, and the inflammatory response in SAP mice by down-regulating the activation of NF-κB and the NLRP3 inflammasome.

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Induction of Apoptosis of Metastatic Mammary Carcinoma Cells In Vivo by Disruption of Tumor Cell Surface CD44 Function

Journal of Experimental Medicine ◽

10.1084/jem.186.12.1985 ◽

1997 ◽

Vol 186 (12) ◽

pp. 1985-1996 ◽

Cited By ~ 172

Author(s):

Qin Yu ◽

Bryan P. Toole ◽

Ivan Stamenkovic

Keyword(s):

Cell Surface ◽

Tumor Cell ◽

Tumor Cells ◽

Lung Tissue ◽

Mammary Carcinoma ◽

Cell Types ◽

Pulmonary Endothelium ◽

Soluble Cd44

To understand how the hyaluronan receptor CD44 regulates tumor metastasis, the murine mammary carcinoma TA3/St, which constitutively expresses cell surface CD44, was transfected with cDNAs encoding soluble isoforms of CD44 and the transfectants (TA3sCD44) were compared with parental cells (transfected with expression vector only) for growth in vivo and in vitro. Local release of soluble CD44 by the transfectants inhibited the ability of endogenous cell surface CD44 to bind and internalize hyaluronan and to mediate TA3 cell invasion of hyaluronan-producing cell monolayers. Mice intravenously injected with parental TA3/St cells developed massive pulmonary metastases within 21–28 d, whereas animals injected with TA3sCD44 cells developed few or no tumors. Tracing of labeled parental and transfectant tumor cells revealed that both cell types initially adhered to pulmonary endothelium and penetrated the interstitial stroma. However, although parental cells were dividing and forming clusters within lung tissue 48 h following injection, >80% of TA3sCD44 cells underwent apoptosis. Although sCD44 transfectants displayed a marked reduction in their ability to internalize and degrade hyaluronan, they elicited abundant local hyaluronan production within invaded lung tissue, comparable to that induced by parental cells. These observations provide direct evidence that cell surface CD44 function promotes tumor cell survival in invaded tissue and that its suppression can induce apoptosis of the invading tumor cells, possibly as a result of impairing their ability to penetrate the host tissue hyaluronan barrier.

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The in Vivo and in Vitro Biosynthesis of Lung Tissue Glycopeptides

Archives of Internal Medicine ◽

10.1001/archinte.1971.00310170061007 ◽

1971 ◽

Vol 127 (5) ◽

pp. 853 ◽

Cited By ~ 3

Author(s):

Luigi De Luca

Keyword(s):

Lung Tissue ◽

In Vitro Biosynthesis

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Cathepsin B promotes collagen biosynthesis driving Bronchiolitis Obliterans Syndrome

European Respiratory Journal ◽

10.1183/13993003.01416-2020 ◽

2020 ◽

pp. 2001416

Author(s):

Carmela Morrone ◽

Natalia F. Smirnova ◽

Aicha Jeridi ◽

Nikolaus Kneidinger ◽

Christine Hollauer ◽

...

Keyword(s):

Lung Tissue ◽

Cathepsin B ◽

Bronchiolitis Obliterans ◽

Major Complication ◽

Fibroblast Cell ◽

Bronchiolitis Obliterans Syndrome ◽

Collagen Deposition ◽

The Impact

Bronchiolitis obliterans syndrome (BOS) is a major complication after lung transplantation (LTx). BOS is characterised by massive peribronchial fibrosis, leading to air trapping induced pulmonary dysfunction. Cathepsin B, a lysosomal cysteine-protease, was shown to enforce fibrotic pathways in several diseases. However, the relevance of Cathepsin B in BOS progression has not yet been addressed. The aim of the study was to elucidate the function of Cathepsin B in BOS pathogenesis.We determined Cathepsin B levels in BAL fluid and lung tissue from healthy donors (HD) and BOS LTx patients. Furthermore, Cathepsin B activity was assessed via a FRET-based assay and protein expression was determined using Western blotting, ELISA, and immunostaining. To investigate the impact of Cathepsin B in the pathophysiology of BOS, we used an in-vivo orthotopic left-LTx mouse model. Mechanistic studies were performed in-vitro using macrophage and fibroblast cell lines.We found a significant increase of Cathepsin B activity in BALF and lung tissue from BOS patients, as well as in our murine model of lymphocytic bronchiolitis (LB). Moreover, Cathepsin B activity was associated with an increased biosynthesis of collagen, and negatively affected lung function. Interestingly, we observed that Cathepsin B was mainly expressed in macrophages that infiltrated areas characterised by a massive accumulation of collagen deposition. Mechanistically, macrophage-derived Cathepsin B contributed to TGF-β1-dependent activation of fibroblasts, and its inhibition reversed the phenotype.Infiltrating macrophages release active Cathepsin B promoting fibroblast-activation and subsequent collagen deposition, driving BOS. Cathepsin B represents a promising therapeutic target to prevent the progression of BOS.

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Premobilization of CD133+ progenitors is associated with attenuated inflammation-induced pulmonary dysfunction following extracorporeal circulation in mice

Interactive Cardiovascular and Thoracic Surgery ◽

10.1093/icvts/ivaa074 ◽

2020 ◽

Vol 31 (2) ◽

pp. 210-220

Author(s):

Dan Luo ◽

Xinhao Liu ◽

Jie Zhang ◽

Lei Du ◽

Lin Bai ◽

...

Keyword(s):

Acute Kidney Injury ◽

Lung Injury ◽

Bronchoalveolar Lavage ◽

Lung Tissue ◽

Extracorporeal Circulation ◽

Kidney Injury ◽

Inflammatory Factors ◽

Pulmonary Dysfunction

Abstract OBJECTIVES Progenitor cells mobilized by granulocyte colony-stimulating factor (G-CSF) have been shown to lessen acute kidney injury induced by extracorporeal circulation (ECC). Both acute kidney injury and lung injury are characterized by endothelial dysfunction. Our goal was to examine whether and how G-CSF-mobilized progenitors with endothelial capacity may help mitigate ECC-induced pulmonary dysfunction. METHODS G-CSF (10 μg/kg/day) was administered subcutaneously to C57BL/6 mice before or at the initiation of the ECC process, after which lung injury was assessed by measuring neutrophils in the fluid from bronchoalveolar lavage and determining the pathological score in lung tissue. CD133+ progenitors were isolated and injected into C57BL/6 mice before ECC in vivo. We incubated the CD133+ cells with pulmonary monocytes or neutrophils isolated from naïve mice in vitro. RESULTS Pretreatment with G-CSF for 2 days significantly decreased the number of neutrophils in the bronchoalveolar lavage fluid, and the pathological score (P < 0.01; n = 5) improved the PaO2/FiO2 ratio [193.4 ± 12.7 (ECC without G-CSF) vs 305.6 ± 22.6 mmHg (ECC with G-CSF); P = 0.03, n = 5] and suppressed neutrophil elastase and tumour necrosis factor-α levels in the circulation; we also observed increases in both circulating and pulmonary populations of CD133+ progenitors. Similar effects were observed in animals pretreated with CD133+ progenitors instead of G-CSF before ECC. The majority of CD133+/CD45− and CD133+/CD45+ progenitors were mobilized in the lung and in the circulation, respectively. Incubating CD133+ progenitors with neutrophils or pulmonary monocytes blocked lipopolysaccharide-induced release of inflammatory factors. CONCLUSIONS Our results suggest that pretreatment of G-CSF attenuates ECC-induced pulmonary dysfunction through inhibiting the inflammatory response in lung tissue and in the circulation with associated premobilization of CD133+ progenitors.

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Loss of Oncostatin M Signaling in Adipocytes Induces Insulin Resistance and Adipose Tissue Inflammation in Vivo

Journal of Biological Chemistry ◽

10.1074/jbc.m116.739110 ◽

2016 ◽

Vol 291 (33) ◽

pp. 17066-17076 ◽

Cited By ~ 14

Author(s):

Carrie M. Elks ◽

Peng Zhao ◽

Ryan W. Grant ◽

Hardy Hang ◽

Jennifer L. Bailey ◽

...

Keyword(s):

Insulin Resistance ◽

Adipose Tissue ◽

Cell Types ◽

Oncostatin M ◽

Adipose Tissue Inflammation ◽

High Fat ◽

Tissue Inflammation ◽

Fat Feeding

Oncostatin M (OSM) is a multifunctional gp130 cytokine. Although OSM is produced in adipose tissue, it is not produced by adipocytes. OSM expression is significantly induced in adipose tissue from obese mice and humans. The OSM-specific receptor, OSM receptor β (OSMR), is expressed in adipocytes, but its function remains largely unknown. To better understand the effects of OSM in adipose tissue, we knocked down Osmr expression in adipocytes in vitro using siRNA. In vivo, we generated a mouse line lacking Osmr in adiponectin-expressing cells (OSMRFKO mice). The effects of OSM on gene expression were also assessed in vitro and in vivo. OSM exerts proinflammatory effects on cultured adipocytes that are partially rescued by Osmr knockdown. Osm expression is significantly increased in adipose tissue T cells of high fat-fed mice. In addition, adipocyte Osmr expression is increased following high fat feeding. OSMRFKO mice exhibit increased insulin resistance and adipose tissue inflammation and have increased lean mass, femoral length, and bone volume. Also, OSMRFKO mice exhibit increased expression of Osm, the T cell markers Cd4 and Cd8, and the macrophage markers F4/80 and Cd11c. Interestingly, the same proinflammatory genes induced by OSM in adipocytes are induced in the adipose tissue of the OSMRFKO mouse, suggesting that increased expression of proinflammatory genes in adipose tissue arises both from adipocytes and other cell types. These findings suggest that adipocyte OSMR signaling is involved in the regulation of adipose tissue homeostasis and that, in obesity, OSMR ablation may exacerbate insulin resistance by promoting adipose tissue inflammation.

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Comparison of In Vitro and In Vivo Rates of Collagen Synthesis in Normal and Damaged Lung Tissue

Experimental Lung Research ◽

10.3109/01902148609061492 ◽

1986 ◽

Vol 10 (2) ◽

pp. 187-201 ◽

Cited By ~ 10

Author(s):

James P. Kehrer ◽

Yu-Chen C. Lee ◽

Suzanne M. Solem

Keyword(s):

Lung Tissue ◽

Collagen Synthesis

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In VitroandIn VivoEvaluation of APX001A/APX001 and Other Gwt1 Inhibitors againstCryptococcus

Antimicrobial Agents and Chemotherapy ◽

10.1128/aac.00523-18 ◽

2018 ◽

Vol 62 (8) ◽

Cited By ~ 34

Author(s):

Karen Joy Shaw ◽

Wiley A. Schell ◽

Jonathan Covel ◽

Gisele Duboc ◽

C. Giamberardino ◽

...

Keyword(s):

Brain Tissue ◽

Lung Tissue ◽

Fungal Infections ◽

Treatment Options ◽

Content Type ◽

Fungal Burden ◽

Geographical Regions ◽

Current Therapies

ABSTRACTCryptococcal meningitis (CM), caused primarily byCryptococcus neoformans, is uniformly fatal if not treated. Treatment options are limited, especially in resource-poor geographical regions, and mortality rates remain high despite current therapies. Here we evaluated thein vitroandin vivoactivity of several compounds, including APX001A and its prodrug, APX001, currently in clinical development for the treatment of invasive fungal infections. These compounds target the conserved Gwt1 enzyme that is required for the localization of glycosylphosphatidylinositol (GPI)-anchored cell wall mannoproteins in fungi. The Gwt1 inhibitors had low MIC values, ranging from 0.004 μg/ml to 0.5 μg/ml, against bothC. neoformansandC. gattii. APX001A and APX2020 demonstratedin vitrosynergy with fluconazole (fractional inhibitory concentration index, 0.37 for both). In a CM model, APX001 and fluconazole each alone reduced the fungal burden in brain tissue (0.78 and 1.04 log10CFU/g, respectively), whereas the combination resulted in a reduction of 3.52 log10CFU/g brain tissue. Efficacy, as measured by a reduction in the brain and lung tissue fungal burden, was also observed for another Gwt1 inhibitor prodrug, APX2096, where dose-dependent reductions in the fungal burden ranged from 5.91 to 1.79 log10CFU/g lung tissue and from 7.00 and 0.92 log10CFU/g brain tissue, representing the nearly complete or complete sterilization of lung and brain tissue at the higher doses. These data support the further clinical evaluation of this new class of antifungal agents for the treatment of CM.

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Humic-like substances in cigarette smoke condensate and lung tissue of smokers

AJP Lung Cellular and Molecular Physiology ◽

10.1152/ajplung.1994.266.4.l382 ◽

1994 ◽

Vol 266 (4) ◽

pp. L382-L388 ◽

Cited By ~ 6

Author(s):

A. J. Ghio ◽

J. Stonehuerner ◽

D. R. Quigley

Keyword(s):

Free Radical ◽

Cigarette Smoke ◽

Lung Tissue ◽

Cigarette Smoke Exposure ◽

Cigarette Smoke Condensate ◽

Free Radical Generation ◽

Carboxylate Content ◽

Radical Generation

Deposition of pigmented matter in the lower respiratory tract correlates with the extent of emphysema in smokers as well as with free radical generation and iron accumulation. Pulmonary emphysema is postulated to be mediated by free radical generation which is either directly or indirectly associated with cigarette smoke exposure. The hypothesis was tested that 1) incomplete combustion of tobacco yields humic-like substances (HLS) which 2) deposit in the lung as pigmented particulates, 3) complex iron cations in vitro and in vivo, and 4) have a capacity to catalyze oxidant formation. HLS, isolated by alkali extraction of cigarette smoke condensate (CSC) (Tobacco Health Research Institute, University of Kentucky), demonstrated a high carbon and low carboxylate content on elemental and functional group analyses, respectively, compared with values for HLS sequestered from soils. The HLS isolated from CSC had a capacity to complex iron in vitro and accumulated the metal in vivo after intratracheal instillation in an animal model. Both HLS and its iron complex generated free radicals, and some portion of this oxidant generation was metal dependent. Lung tissue collected at autopsy from smokers contained HLS with an infrared spectrum almost identical to that of the material isolated from CSC. Associations between particulate deposition, metal accumulation, and free radical generation suggest a possible role of HLS in the induction of lung disease following cigarette exposure.

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