The role of NOXO1 in the mouse model of cigarette smoke-induced emphysema and pulmonary hypertension
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ABSTRACT: NOXO1 KO mice seem to be protected from cigarette smoke-induced emphysema and pulmonary hypertension. Since the molecular mechanisms are not clear yet, this microarray experiment should help to identify the molecular differences in these KO mice compared to the wild-type (WT), figuring out how the protection occurs. Since we believe that vascular altertions could not only be responsible for vascular remodeling but also the trigger for emphysema development, we microdissected pre-capillary vessels from WT and KO mice, both controls and smoke-exposed. In addition, alveolar septa were microdissected to investigate the alveolar changes.
Project description:Chronic Obstructive Pulmonary Disease, which is comprised of chronic bronchitis and emphysema, is a leading cause of morbidity and mortality. Because tissue destruction is the prominent characteristic of emphysema, extracellular proteinases, particularly those with elastolytic ability, are often considered to be key drivers in this disease. Several human and mouse studies have implicated roles for matrix metalloproteinases (MMPs), particularly macrophage-derived proteinases, in COPD pathogenesis. MMP28 is expressed by the pulmonary epithelium and macrophage, and we have found that it regulates macrophage recruitment and polarization. We hypothesized that MMP28 would have contributory roles in emphysema via alteration of macrophage numbers and activation. Because of the established association of emphysema pathogenesis to macrophage influx, we evaluated the inflammatory changes and lung histology of Mmp28-/- mice exposed to 3 and 6 months of cigarette smoke. At earlier time-points, we found altered macrophage polarization in the smoke-exposed Mmp28-/- lung consistent with other published findings that MMP28 regulates macrophage activation. At both 3 and 6 months, Mmp28-/- mice had blunted inflammatory responses more closely resembling non-smoked mice, with a reduction in neutrophil recruitment and CXCL1 chemokine expression. By 6 months, Mmp28-/- mice were protected from emphysema. These results highlight a previously unrecognized role for MMP28 in promoting chronic lung inflammation and tissue remodeling induced by cigarette smoke and highlight another potential target to modulate COPD.
Project description:A majority of the gas-exchange surface is generated during alveologenesis, and disruption of this process causes bronchopulmonary dysplasia (BPD) in preterm infants, characterized by alveolar simplification. BPD is a significant risk factor for adult emphysema, marked by alveolar loss. A comprehensive molecular understanding of alveologenesis and effective treatments for BPD and emphysema are still lacking. Here, we show that the cells expressing Hhip, a gene associated with both BPD and emphysema, expand within the alveoli during alveologenesis, followed by hedgehog (Hh) inhibition and myofibroblast transition. Stromal-specific deletion of Hhip leads to aberrant persistence of SMA+ alveolar myofibroblasts, mediated by a hyperactive Hh-IGF1 axis. Conditional knockout animal and 3D stroma-stem cell organoid models demonstrate that loss of Hhip induces alveolar stem/progenitor cell senescence in a non–cell-autonomous manner. Alveolar simplification and BPD phenotypes induced by Hhip deletion can be partially rescued by IGF1 signaling blockade. We also observe the downregulation of Hhip expression and hyperactivation of Hh-IGF1 signaling in hyperoxia-induced BPD animal models. In addition, adult mice deficient in Hhip expression develop emphysema phenotype with abnormal alveolar myofibroblasts. Finally, we develop a therapeutic Fc-fused HHIP recombinant protein that attenuates BPD phenotypes in postnatal mice and emphysema in adult mice. These findings underscore the critical role of HHIP in coordinating alveologenesis and preventing BPD and emphysema by restricting Hh-IGF1 signaling.
Project description:Emphysema is a major pathological phenotype of chronic obstructive pulmonary disease (COPD) that is characterized by progressive and irreversible alveolar tissue destruction caused by several stressors, such as tobacco smoke and air pollution. It remains incurable in part due to an incomplete understanding of cellular and molecular mechanisms underlying the failure of tissue repair. Here, we have generated a single cell RNA sequencing dataset of enriched epithelial cells from emphysematous parenchymal lung tissue of COPD patients and from healthy controls.Using this dataset, we performed high resolution analysis of 78,699 ATII cells and reveal novel ATII cell subsets in severe emphysema and health. These include two ATII sub-clusters expressing various secretoglobin mRNAs (SCGBpos) in COPD that present distinct transcriptomic profiles compared to healthy sub-clusters. These ATII sub-clusters that are present in human COPD are also found in a mouse emphysema model. Importantly, the COPD specific ATII cells from both species demonstrate airway origins and fail to undergo alveolar differentiation in organoid cultures, thereby suggesting that a common mechanism in emphysema pathogenesis.
Project description:Emphysema is a major pathological phenotype of chronic obstructive pulmonary disease (COPD) that is characterized by progressive and irreversible alveolar tissue destruction caused by several stressors, such as tobacco smoke and air pollution. It remains incurable in part due to an incomplete understanding of cellular and molecular mechanisms underlying the failure of tissue repair. Here, we have generated a single cell RNA sequencing dataset of enriched epithelial cells from emphysematous parenchymal lung tissue of COPD patients and from healthy controls. Using this dataset, we performed high resolution analysis of 78,699 ATII cells and reveal novel ATII cell subsets in severe emphysema and health. These include two ATII sub-clusters expressing various secretoglobin mRNAs (SCGBpos) in COPD that present distinct transcriptomic profiles compared to healthy sub-clusters. These ATII sub-clusters that are present in human COPD are also found in a mouse emphysema model. Importantly, the COPD specific ATII cells from both species demonstrate airway origins and fail to undergo alveolar differentiation in organoid cultures, thereby suggesting that a common mechanism in emphysema pathogenesis.
Project description:HIV1+ smokers develop emphysema at an earlier age and with a higher incidence than HIV1- smokers. Based on the knowledge that human alveolar macrophages (AM) are capable of producing proteases that degrade extracellular matrix components, we hypothesized that upregulation of AM matrix metalloproteinases may be associated with the emphysema of HIV1+ smokers. To test this hypothesis, microarray analysis was used to screen which MMP genes were expressed by AM isolated by bronchoalveolar lavage (BAL) of HIV1+ smokers with early emphysema. For each of the MMP genes observed to be expressed (MMP-1, -2, -7, -9, -10, -12 and -14), TaqMan PCR was used to quantify the relative expression in AM from 4 groups of individuals: HIV1 healthy nonsmokers, HIV1- healthy smokers, HIV1- smokers with early emphysema and HIV1+ smokers with early emphysema. Strikingly, while AM gene expression of MMPs was higher in HIV1- individuals with emphysema in comparison with HIV1- healthy smokers, for the majority of the MMPs (-1, -7, -9, -10, -12), AM expression from HIV1+ smokers with early emphysema was significantly higher than HIV1- smokers with early emphysema. Consistent with these observations, HIV1+ individuals with early emphysema had higher levels of epithelial lining fluid MMPs (-2, -7, -9,-12) than the 3 HIV1 groups. Interestingly, the active forms of MMP-2, -9 and -12 were detected in epithelial lining fluid from HIV1+ individuals with early emphysema, but not in any of the other groups. Considering that the substrate specificity of the upregulated AM MMPs includes collagenases, gelatinases, matrilysins and elastase, these data suggest that upregulated AM MMP genes and activation of MMP proteins may contribute to the emphysema of HIV1+ individuals who smoke. Keywords: expression study Asymptomatic HIV+ smokers with early emphysema
Project description:Chronic obstructive pulmonary disease (COPD) is a complex pulmonary disorder primarily induced by cigarette smoking, and characterized by persistent airflow limitation. The mouse represents an important model for studying COPD pathologies such as lung emphysema. In this respect, a number of mechanistic studies have been performed, however the approaches were mostly focused on single gene analysis or characterization of cellular, inflammatory or histopathological changes without attempting a more comprehensive interpretation. In the present study we aimed at applying systems biology approach to identify genome-wide molecular mechanisms indicative of cigarette smoke (CS)-induced lung emphysema. The lung transcriptomes of five mouse models (C57BL/6, ApoE-/-, A/J, CD1, and Nrf2-/-), that are known to be susceptible to CS-induced emphysema development, were analyzed following prolonged (5-6 months) CS exposure. The investigation resulted in the confirmation of many existing mechanistic explanations underlying smoke-induced lung emphysema, including increased transcriptional activity of NF-?B, and increased levels of TNF-a, IFN-g, and IL-1b. More importantly, we predicted mechanisms without currently well-documented roles, including increased transcriptional activity of PU.1, STAT1, C/EBP, FOXM1, YY1 and N-cor, and increased IL-17 cytokine expression, and reduced protein expression of ITGB6 and CFTR. We also corroborated, by using targeted proteomic approaches, several predictions such as reduced expression of ITGB6 and increased expression of BRCA1, C/EBPs, PU.1, TNF-a, IL-1b or CSF2. We believe this study will provide more insights into better understanding of CS-induced molecular processes underlying emphysema development in mice that may eventually be relevant in humans.
Project description:We have previously shown that mice with loss of C-type lectin-like type II (CLEC2), which have lymphatic dysfunction due to the role of CLEC2 in platelets for maintaining separation between the venous and lymphatic system, develop lung tertiary lymphoid organ (TLO) formation and lung injury that resembles an emphysema phenotype of chronic obstructive pulmonary disease (COPD). We now sought to investigate whether and how TLOs in these mice may play a pathogenic role in lung injury that is relevant to human disease. We found that inhibiting TLO formation using an anti-CD20 antibody in CLEC2-deficient mice partially blocked the development of emphysema. TLOs in CLEC2-deficient mice were rich in plasma cells and were a source of a broad array of autoantibodies. Chronic cigarette smoke exposure increased the size and number of lung TLOs in CLEC2-deficient mice, and was associated with increased markers of antigen presentation and maturation, leading to increased autoantibody deposition. Using lung tissue from COPD patients, we found an increase in lymphatic markers in patients with an emphysema phenotype and autoreactive TLOs compared to COPD patients without emphysema that lack prominent TLOs. Taken together, these results demonstrate that emphysema in mice with lymphatic dysfunction can be partially rescued by blocking TLO formation, and that these TLOs are source of autoantibodies that are exacerbated by cigarette smoke. Our work suggests that lymphatic dysfunction in mice may recapitulate some aspects an autoimmune emphysema phenotype that is seen in a subset of patients with COPD.
Project description:HIV1+ smokers develop emphysema at an earlier age and with a higher incidence than HIV1- smokers. Based on the knowledge that human alveolar macrophages (AM) are capable of producing proteases that degrade extracellular matrix components, we hypothesized that upregulation of AM matrix metalloproteinases may be associated with the emphysema of HIV1+ smokers. To test this hypothesis, microarray analysis was used to screen which MMP genes were expressed by AM isolated by bronchoalveolar lavage (BAL) of HIV1+ smokers with early emphysema. For each of the MMP genes observed to be expressed (MMP-1, -2, -7, -9, -10, -12 and -14), TaqMan PCR was used to quantify the relative expression in AM from 4 groups of individuals: HIV1 healthy nonsmokers, HIV1- healthy smokers, HIV1- smokers with early emphysema and HIV1+ smokers with early emphysema. Strikingly, while AM gene expression of MMPs was higher in HIV1- individuals with emphysema in comparison with HIV1- healthy smokers, for the majority of the MMPs (-1, -7, -9, -10, -12), AM expression from HIV1+ smokers with early emphysema was significantly higher than HIV1- smokers with early emphysema. Consistent with these observations, HIV1+ individuals with early emphysema had higher levels of epithelial lining fluid MMPs (-2, -7, -9,-12) than the 3 HIV1 groups. Interestingly, the active forms of MMP-2, -9 and -12 were detected in epithelial lining fluid from HIV1+ individuals with early emphysema, but not in any of the other groups. Considering that the substrate specificity of the upregulated AM MMPs includes collagenases, gelatinases, matrilysins and elastase, these data suggest that upregulated AM MMP genes and activation of MMP proteins may contribute to the emphysema of HIV1+ individuals who smoke. Keywords: expression study
Project description:To assess the mechanism which caused emphysema in the IQOS group, we performed microarray analysis using homogenate lung tissue that were exposed to fresh air, IQOS aerosol, or cigarette smoke for 6 months. In microarray-based analysis, gene expressions to the air group were different in the IQOS and CS group, and apoptosis-related pathways were enhanced in the IQOS group. Apoptosis-related protein (cytochrome c, cleaved caspase-3, and cleaved PARP1) expression in the IQOS group were higher than air group in homogenete lungs. More single-stranded DNA and TUNEL positive alveolar cells were found in the IQOS group than control significantly.
Project description:Chronic obstructive pulmonary disease (COPD) is characterized by a progressive decline in lung function, caused by exposure to exogenous particles, mainly cigarette smoke (CS). COPD pathogenesis is initiated and perpetuated by an abnormal CS-induced inflammatory response of the lungs, involving both innate and adaptive immunity. Specifically, B cells organized in iBALT structures, as well as macrophages, accumulate in the lungs and contribute to CS-induced emphysema, but the mechanisms thereof remain unclear. Here, we demonstrate that B cell-deficient mice are significantly protected against CS-induced emphysema. Chronic CS exposure led to increased lung compliance, total lung capacity, and mean linear chord length in WT, but not B cell-deficient mice, associated with an increased size and number of iBALT structures. The increased accumulation of macrophages around iBALT and in emphysematous alveolar areas in CS-exposed WT mice coincided with upregulated MMP12 expression. In vitro co-culture experiments using B cells and macrophages demonstrated that B cell-derived IL-10 drives macrophage activation and MMP12 upregulation. In summary, B cell function in iBALT formation in CS-induced emphysema provides a new innovative mechanism, which could be explored as a target for therapeutic intervention in COPD patients. Expression data of mice treated with cigarette smoke. Lung tissue was analysed at four and six months of age.