American journal of physiology. Lung cellular and molecular physiology最新文献

{"title":"Development of a preclinical model of ICU-associated sleep fragmentation and effects on pneumonia recovery in mice.","authors":"Mahendra Damarla, Karthik Suresh, Linda Zheng, Kathleen Carino, Melissa Turner, Othello Del Rosario, Franco D'Alessio, Andres Villabona-Rueda, Neil Aggarwal, Ananya Mukandan, Alessandro D'Alessio, Neha Skandan, Samuel Murray, Naina Gour, Stephane Lajoie, Kimberly M Davis, Larissa A Shimoda, Naresh M Punjabi","doi":"10.1152/ajplung.00210.2024","DOIUrl":"10.1152/ajplung.00210.2024","url":null,"abstract":"<p><p>Patients in the intensive care unit (ICU) experience many ICU-specific factors that could impact their outcomes apart from their underlying acute illness. The precise function of sleep is not clear, but its importance is suggested by the literature on the deleterious effects of poor sleep and sleep deprivation and may represent a modifiable opportunity in ICU patients. Investigation into the role of sleep in critical illness is impeded by a lack of sufficient murine models. Although many murine models of sleep disruption exist, these do not replicate the ICU patient experience. We modified a traditional model of sleep fragmentation, that is, intermittent orbital shaking, with increased duration and intensity of shaking, and 2-h on and 2-h off light/dark cycles to create an ICU-associated sleep fragmentation model. Continuous electroencephalogram analyses identified significantly reduced total sleep time, significantly fragmented sleep, and a loss of the diurnal sleep-wake cycle in mice exposed to the ICU sleep fragmentation protocol, but not in mice exposed to a traditional sleep fragmentation protocol when compared with baseline conditions. Using a <i>Streptococcus pneumoniae</i> murine model of pneumonia to mimic critical illness, we note a delay in resolution of markers of lung injury in mice exposed to the ICU sleep fragmentation protocol when compared with <i>S. pneumoniae</i> alone. We conclude that traditional sleep fragmentation models may not recapitulate the ICU patient sleep experience. Investigators could use this ICU sleep fragmentation model for mechanistic studies of how sleep disruption in the ICU affects critical illness outcomes.<b>NEW & NOTEWORTHY</b> The study of sleep and its interaction with critical illness has been limited partly due to a paucity of representative models. We developed an ICU-associated sleep fragmentation model that recapitulates many of the key features of sleep experienced by patients in the intensive care unit. Furthermore, we observed delayed recovery in lung injury in an <i>S. pneumoniae</i> murine model when exposed to ICU sleep fragmentation.</p>","PeriodicalId":7593,"journal":{"name":"American journal of physiology. Lung cellular and molecular physiology","volume":" ","pages":"L650-L660"},"PeriodicalIF":3.6,"publicationDate":"2025-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12186240/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143708195","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Increasing heterogeneity is associated with <i>IL-6</i> expression in the lungs following mechanical ventilation.","authors":"Ella Smalley, David Trevascus, Yong Song, Melissa Preissner, Peter A Dargaville, Martin Donnelley, Kaye Morgan, Stephen Dubsky, Graeme R Zosky","doi":"10.1152/ajplung.00271.2024","DOIUrl":"https://doi.org/10.1152/ajplung.00271.2024","url":null,"abstract":"<p><p>This study aimed to characterize how peak inspiratory pressure (PIP) and positive end-expiratory pressure (PEEP) influence regional lung volume heterogeneity as a result of mechanical ventilation and the influence of this heterogeneity on markers of inflammation within the lungs. Four groups of <i>BALB/C</i> mice (<i>n</i> = 7 or 8 per group) were mechanically ventilated for 2 h using low or high (12 cmH₂O or 20 cmH₂O) peak inspiratory pressure (PIP) with or without 2 cmH₂O positive end-expiratory pressure (PEEP). Four-dimensional computed tomography (4-DCT) images were acquired using synchrotron-based radiation source at baseline and after 2 h. Regional tidal volumes were obtained by 4-D cross-correlational X-ray velocimetry, whereas end-expiratory volume was quantified by Hounsfield units. Tissue was harvested from 10 lung regions, and expression of <i>IL-6</i> and monocyte chemo-attractant protein 1 (<i>MCP-1</i>) was quantified using qPCR. We found a significant reduction in specific end-expiratory volume (sEEV) in mice ventilated with low PIP and no PEEP and a reduction in tidal volume in groups without PEEP. End-expiratory volume heterogeneity decreased in the low PIP and no PEEP group, whereas tidal volume heterogeneity decreased in the equivalent high PIP group, potentially due to regional redistribution of lung volumes. We found associations between <i>IL-6</i> expression and tidal volume heterogeneity. In this study, we have demonstrated that changes in PIP and PEEP impact atelectasis, overdistension, and heterogeneity, and that increases in tidal volume heterogeneity may be driving <i>IL-6-</i>mediated biotrauma. These findings highlight the importance of considering the spatial distribution of tidal volumes as a driver of lung injury during mechanical ventilation.<b>NEW & NOTEWORTHY</b> The combination of low inspiratory and expiratory pressure promotes atelectasis but is not associated with markers of injury in the healthy lung during short-term ventilation. High inspiratory pressures promote tidal volume heterogeneity, which is correlated with the expression of genetic markers of lung injury. These data suggest that heterogeneity in tidal volume may be a key driver of biotrauma in the healthy, mechanically ventilated lung.</p>","PeriodicalId":7593,"journal":{"name":"American journal of physiology. Lung cellular and molecular physiology","volume":"328 5","pages":"L738-L747"},"PeriodicalIF":3.6,"publicationDate":"2025-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143959568","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Role of <i>N</i>-glycosylation of surfactant protein SP-B^N in lipid and SP-B interacting properties. Implications in disease.","authors":"Miriam Isasi-Campillo, Paula Rangel-Arranz, Lucía García-Ortega, Jesús Pérez-Gil","doi":"10.1152/ajplung.00350.2024","DOIUrl":"https://doi.org/10.1152/ajplung.00350.2024","url":null,"abstract":"<p><p>SP-B^N is an independent protein derived from the precursor of pulmonary surfactant protein B (SP-B), a critical component of the pulmonary surfactant (PS), the membrane-based system that coats the alveolar air-liquid interface and is essential for both respiratory mechanics and innate defense. In humans, a single-nucleotide polymorphism (SNP) defining hSP-B^N glycosylation has been associated with propensity to certain respiratory diseases, but molecular studies in this regard are scarce. Previous studies with the murine SP-B^N, nonglycosylated, have suggested a role for this protein in lipid transfer during PS biogenesis. This study focuses on the structural and functional characterization of both glycosylated and nonglycosylated human SP-B^N protein variants to elucidate the impact of <i>N</i>-glycosylation. Recombinant proteins (hSP-B^N, glycosylated, and hSP-B^N-T73I, nonglycosylated) were produced in <i>Pichia pastoris</i> and purified to homogeneity. The structural characterization confirmed the main features of hSP-B^N as a member of the SAPLIP protein family: mainly α-helical, a propensity to dimerization and a high stability. Interestingly, <i>N</i>-glycosylation did not significantly affect hSP-B^N structure. Regarding lipid interactions, both hSP-B^N variants were able to bind and perturb membranes in lipid vesicles with a PS-like composition at acidic, but not neutral pH, which is relevant given the acidification during PS biogenesis. Remarkably, <i>N</i>-glycosylation impaired the synergistic effect of hSP-B^N and mature SP-B to promote lipid mixing/transfer activity. These results support the joint action of both proteins in PS biogenesis and, more importantly, suggest that this combined activity affected with the SNP-induced glycosylation of hSP-B^N could be behind certain PS defects acquired during biogenesis causing some susceptibility to respiratory diseases.<b>NEW & NOTEWORTHY</b> The impact of <i>N</i>-glycosylation on the structure and function of human SP-B^N protein has been studied. Homogeneous production of glycosylated hSP-B^N and nonglycosylated hSP-B^N-T73I was achieved in <i>Pichia pastoris.</i> Structural characterization and lipid interaction properties at acidic pH revealed no significant differences due to glycosylation. <i>N</i>-glycosylation impairs the synergistic action of hSP-B^N and SP-B in lipid transfer/mixing activity. <i>N</i>-glycosylation of hSP-B^N could impair PS biogenesis, in agreement with its potential involvement in respiratory disease.</p>","PeriodicalId":7593,"journal":{"name":"American journal of physiology. Lung cellular and molecular physiology","volume":"328 5","pages":"L700-L715"},"PeriodicalIF":3.6,"publicationDate":"2025-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143957146","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Oxidation of low-density lipoprotein by hemoglobin causes pulmonary microvascular endothelial barrier dysfunction through lectin-like oxidized LDL receptor 1.","authors":"Jamie E Meegan, Kyle J Riedmann, Samantha Gonski, Joel S Douglas, Avery M Bogart, Lorraine B Ware, Julie A Bastarache","doi":"10.1152/ajplung.00026.2025","DOIUrl":"10.1152/ajplung.00026.2025","url":null,"abstract":"<p><p>Elevated circulating cell-free hemoglobin (Hb) is a pathological driver of endothelial injury and contributes to disease severity and organ dysfunction during several pathologies, including sickle cell disease, pulmonary hypertension, primary graft dysfunction after lung transplantation, and sepsis. However, the signaling mechanisms involved in Hb-mediated pulmonary microvascular endothelial barrier dysfunction are not well understood. One mechanism by which Hb may contribute to microvascular endothelial barrier dysfunction is through its ability to oxidize circulating lipids and lipoproteins, including low-density lipoproteins (LDLs). In this study, we hypothesized that oxidation of LDL (oxLDL) by Hb (Hb-oxLDL) disrupts the pulmonary microvascular endothelial barrier via the scavenger receptor for oxLDL, lectin-like oxidized LDL receptor 1 (LOX-1). We stimulated primary human pulmonary microvascular endothelial cells with Hb-oxLDL and found significant disruption to the endothelial barrier. Barrier dysfunction by Hb-oxLDL was partially prevented by haptoglobin or LOX-1 inhibitor. We also found that oxidation of LDL by heme was sufficient to disrupt the endothelial barrier. Together, these data demonstrate that oxidation of LDL by Hb disrupts the pulmonary microvascular endothelial barrier through the LOX-1 receptor, indicating a potential mechanism for Hb-mediated microvascular injury during inflammatory and hemolytic conditions.<b>NEW & NOTEWORTHY</b> This study demonstrates that oxidation of low-density lipoproteins (LDLs) by hemoglobin or heme disrupts the pulmonary microvascular endothelial barrier; the scavenger receptor lectin-like oxidized LDL receptor 1 mediates this response. This study reveals a novel mechanism by which the pulmonary microvascular endothelium could be targeted for therapeutic intervention during hemolytic or inflammatory pathologies.</p>","PeriodicalId":7593,"journal":{"name":"American journal of physiology. Lung cellular and molecular physiology","volume":"328 5","pages":"L748-L755"},"PeriodicalIF":3.6,"publicationDate":"2025-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12117588/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143960811","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Targeting type-2 inflammation in pulmonary hypertension: lessons from a novel model.","authors":"Navneet Singh, William M Oldham","doi":"10.1152/ajplung.00109.2025","DOIUrl":"10.1152/ajplung.00109.2025","url":null,"abstract":"","PeriodicalId":7593,"journal":{"name":"American journal of physiology. Lung cellular and molecular physiology","volume":" ","pages":"L669-L670"},"PeriodicalIF":3.6,"publicationDate":"2025-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12100054/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143794533","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The impact of electronic cigarettes on airway epithelial barrier integrity in preclinical mouse model.","authors":"Amelia L Beaumont, Andjela Raduka, Nannan Gao, Claire E Lee, Robert L Chatburn, Fariba Rezaee","doi":"10.1152/ajplung.00408.2024","DOIUrl":"10.1152/ajplung.00408.2024","url":null,"abstract":"<p><p>The increasing use of electronic cigarettes (e-cigs) among adolescents poses significant public health risks. This study investigates the impact of e-cigs on the airway epithelial barrier, focusing on apical junctional complexes (AJCs), including tight junctions (TJs) and adherens junctions (AJs). We hypothesized that e-cigs disrupt AJCs in a mouse model, leading to increased airway barrier permeability. C57BL/6 mice were exposed to 36 mg/mL e-cig aerosols (3 puffs/min) for 1 h daily over 4 days. Bronchoalveolar lavage (BAL) fluid analysis, lung inflammation assessment, immunohistochemistry (IHC) staining, Western blotting (WB), and permeability assays were performed to evaluate the structure and function of the airway barrier. E-cig-exposed mice showed weight loss and elevated serum cotinine levels. BAL fluid analysis revealed elevated white blood cells. Histological analysis confirmed lung inflammation, whereas IHC and WB showed significant AJC disruption. Notably, claudin-2 levels were elevated in e-cig-exposed mice compared with controls. Claudin-2, known for its role in promoting permeability in \"leaky\" epithelia, increased alongside decreases in other TJ components, signifying structural barrier impairment. After e-cig exposure, instilling fluorescein isothiocyanate (FITC)-dextran into the airway increased serum FITC-dextran levels, indicating enhanced barrier permeability. E-cig aerosol exposure disrupts airway epithelial barrier structure and function, primarily through the disassembly of TJs and AJs. These findings suggest potential pathways for further clinical investigation into the health risks of e-cig use.<b>NEW & NOTEWORTHY</b> The rising use of e-cigs among youth has become a significant public health concern. This study, using a mouse model, demonstrates that exposure to e-cig aerosol leads to airway inflammation, structural damage to the airway epithelial barrier, and increased epithelial barrier permeability.</p>","PeriodicalId":7593,"journal":{"name":"American journal of physiology. Lung cellular and molecular physiology","volume":" ","pages":"L564-L570"},"PeriodicalIF":3.6,"publicationDate":"2025-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12147400/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143584344","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Therapeutic strategies to reverse cigarette smoke-induced ion channel and mucociliary dysfunction in COPD airway epithelial cells.","authors":"Neerupma Silswal, Nathalie Baumlin, Steven Haworth, Robert N Montgomery, Makoto Yoshida, John S Dennis, Sireesha Yerrathota, Michael D Kim, Matthias Salathe","doi":"10.1152/ajplung.00258.2024","DOIUrl":"10.1152/ajplung.00258.2024","url":null,"abstract":"<p><p>Cigarette smoke (CS) is a leading cause of chronic obstructive pulmonary disease (COPD). Here, we investigated whether the ion channel amplifier nesolicaftor rescues CS-induced mucociliary and ion channel dysfunction. As CS increases the expression of transforming growth factor-beta1 (TGF-β1), human bronchial epithelial cells (HBECs) from healthy donors were used for TGF-β1 and COPD donors (COPD-HBEC) for CS exposure experiments. CS and TGF-β1 induce mucociliary dysfunction by increasing MUC5AC and decreasing ion channel conductance important for mucus hydration. These include cystic fibrosis transmembrane conductance regulator (CFTR) and apical large-conductance, Ca²⁺-activated K⁺ (BK) channels. Nesolicaftor rescued CFTR and BK channel dysfunction, restored ciliary beat frequency (CBF), and decreased mucus viscosity and MUC5AC expression in CS-exposed COPD-HBEC. Nesolicaftor further reversed reductions in airway surface liquid (ASL) volumes, CBF, and CFTR and BK conductance, and blocked the increase in extracellular signal-regulated kinase (ERK) signaling in TGF-β1-exposed normal HBECs. Mechanistically, nesolicaftor increased, as expected, not only binding of PCBP1 to <i>CFTR</i> mRNA but also surprisingly to <i>LRRC26</i> mRNA, which encodes the gamma subunit required for BK function. Similar to nesolicaftor, the angiotensin receptor blocker (ARB) losartan rescued TGF-β1-mediated decreases in PCBP1 binding to <i>LRRC26</i> mRNA. In addition, the ARB telmisartan restored PCBP1 binding to <i>CFTR</i> and <i>LRRC26</i> mRNAs to rescue CFTR and BK function in CS-exposed COPD-HBEC. Thus, nesolicaftor and ARBs act on the same target and were therefore neither additive nor synergistic in their actions. These data demonstrate that nesolicaftor and ARBs may provide benefits in COPD by improving ion channel function important for mucus hydration.<b>NEW & NOTEWORTHY</b> Cigarette smoke (CS) increases transforming growth factor-beta1 (TGF-β1) expression that causes mucociliary dysfunction by decreasing ion channel function. In our study, a CFTR amplifier (nesolicaftor) and angiotensin II receptor blockers (losartan and telmisartan) improve CS-induced ion channel dysfunction, by increasing binding of PCBP1 to <i>CFTR</i> and <i>LRRC26</i> mRNAs. Therefore, nesolicaftor and ARBs, acting on the same target, may provide therapeutic benefits for treating smoking-related diseases.</p>","PeriodicalId":7593,"journal":{"name":"American journal of physiology. Lung cellular and molecular physiology","volume":" ","pages":"L571-L585"},"PeriodicalIF":3.6,"publicationDate":"2025-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12188546/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143646950","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Intraamniotic vitamin D preserves lung development and prevents pulmonary hypertension in experimental bronchopulmonary dysplasia due to intraamniotic sFlt-1.","authors":"Michael W Cookson, Tania Gonzalez, Elisa M Bye, Greg Seedorf, Sarah Ellor, Bradford J Smith, James C Fleet, Erica W Mandell","doi":"10.1152/ajplung.00409.2024","DOIUrl":"10.1152/ajplung.00409.2024","url":null,"abstract":"<p><p>Preterm infants born to mothers with preeclampsia, a disease of vascular dysfunction, are at increased risk for bronchopulmonary dysplasia (BPD). Endothelial cells are critical in both maintaining proper vascular function and coordinating lung development. Understanding the mechanisms contributing to BPD in the setting of preeclampsia and how preeclampsia impacts pulmonary endothelial cells (PECs) in the newborn lung are required to decrease the burden of BPD. Vitamin D has been shown to improve lung angiogenesis and lung development in inflammatory models of BPD, but its therapeutic potential in the setting of preeclampsia is unknown. We hypothesized that intraamniotic (IA) treatment with the biologically active form of vitamin D, 1,25 dihydroxyvitamin D [1,25(OH)₂D], will preserve lung growth in an experimental model of BPD induced by antenatal exposure to soluble vascular endothelial growth factor receptor-1 [sFlt-1 (soluble fms-like tyrosine kinase 1)]. Fetal rats were exposed to saline (control), sFlt-1 alone, 1,25(OH)₂D alone, or simultaneous sFlt-1 + 1,25(OH)₂D via IA injection during the late canalicular stage of lung development and delivered 2 days later. IA treatment with 1,25(OH)₂D in sFlt-1-exposed pups improved lung alveolar and vascular growth and function at 14 days of life. PECs orchestrate alveolar development, and we demonstrate that IA sFlt-1 exposure alone decreased in vitro growth and tube formation of PECs isolated from newborn pups and that PECs from pups coexposed to IA sFlt-1 and 1,25(OH)₂D demonstrated increased growth and tube formation. We conclude that IA 1,25(OH)₂D treatment improves distal lung development during sFlt-1 exposure through preservation of angiogenesis in the developing lung.<b>NEW & NOTEWORTHY</b> This study highlights that experimental BPD induced by intraamniotic sFlt-1 is associated with impaired growth in postnatal pulmonary endothelial cells. We demonstrate that 1,25(OH)₂D may be a therapeutic option to improve lung development through enhancement of VEGF signaling and preservation of early pulmonary endothelial growth in the newborn rat lung.</p>","PeriodicalId":7593,"journal":{"name":"American journal of physiology. Lung cellular and molecular physiology","volume":" ","pages":"L603-L615"},"PeriodicalIF":3.6,"publicationDate":"2025-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143690847","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Sodium nitrite prevents impaired postnatal alveolar development.","authors":"Kathrine L Daniel, Chantal Gaudet, Ali Hamraghani, Nadya Ben Fadel, Behzad Yeganeh, Robert P Jankov","doi":"10.1152/ajplung.00324.2024","DOIUrl":"10.1152/ajplung.00324.2024","url":null,"abstract":"<p><p>Deficient nitric oxide (NO) signaling plays a critical role in the pathogenesis of bronchopulmonary dysplasia (BPD); however, clinical trials of inhaled NO (iNO) as a preventive therapy for BPD have shown little to no benefit. A biochemical obstacle to effective NO-based therapy relates to the high reactivity of NO, potentially leading to harmful oxidation and nitration. Hypothesizing that nitrite-based therapy has less potential to produce adverse reactions, we compared the preventive effects of sodium nitrite (NaNO₂) and iNO on lung morphology, NO content and signaling, <i>S</i>-nitrosothiols (SNOs), and tyrosine nitration in a novel rat model of experimental BPD. From <i>postnatal days</i> (PNDs) <i>1</i>-<i>21</i>, rat pups were exposed to normoxia or to hyperoxia-intermittent hypoxia (H-IH; PND 1-7 85% O₂, PND 7-14 60% O₂, and PND 14-21 normoxia with intermittent exposure to 10% O₂ for 10 min every 4 h) while receiving daily subcutaneous (sc) NaNO₂ (20 mg/kg) or continuous iNO (10 ppm). Controls were treated with vehicle or were not exposed to iNO. Exposure to H-IH caused alveolar and pulmonary vascular hypoplasia, pulmonary hypertension (PH), decreased lung NO content and signaling, and increased tyrosine nitration. NaNO₂ prevented abnormal lung morphology and PH, normalized NO content and signaling, and prevented nitration. iNO prevented PH, but had minimal effects on abnormal distal airspace morphology, and caused nitration and alveolar hypoplasia in control (normoxia-exposed) animals. Treatment with NaNO₂ increased <i>S</i>-nitrosylation of nine lung proteins; none were increased by iNO. These observations provide a biological rationale for superior efficacy of NaNO₂ in preventing experimental BPD.<b>NEW & NOTEWORTHY</b> Deficient nitric oxide (NO) signaling plays a critical role in bronchopulmonary dysplasia (BPD); however, human trials of inhaled NO (iNO) to prevent BPD have shown little to no benefit. We compared preventive effects of sodium nitrite (NaNO₂) to iNO in a novel rat model of experimental BPD. NaNO₂ prevented impaired postnatal alveolarization, whereas iNO had minimal effect. NaNO₂ inhibited nitration and enhanced <i>S</i>-nitrosylation of several proteins in the lung, potentially explaining its superiority to iNO.</p>","PeriodicalId":7593,"journal":{"name":"American journal of physiology. Lung cellular and molecular physiology","volume":" ","pages":"L586-L602"},"PeriodicalIF":3.6,"publicationDate":"2025-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143584384","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Culture conditions differentially regulate the inflammatory niche and cellular phenotype of tracheobronchial basal stem cells.","authors":"Shubha Murthy, Denise A Seabold, Lalit K Gautam, Adrian M Caceres, Rosemary Sease, Ben A Calvert, Shana M Busch, Aaron Neely, Crystal N Marconett, Amy L Ryan","doi":"10.1152/ajplung.00293.2024","DOIUrl":"10.1152/ajplung.00293.2024","url":null,"abstract":"<p><p>Bronchial epithelial cells derived from the tracheobronchial regions of human airways (HBECs) provide a valuable in vitro model for studying pathological mechanisms and evaluating therapeutics. This cell population comprises a mixed population of basal cells (BCs), the predominant stem cell in airways capable of both self-renewal and functional differentiation. Despite their potential for regenerative medicine, BCs exhibit significant phenotypic variability in culture. To investigate how culture conditions influence BC phenotype and function, we expanded three independent BC isolates in three media: airway epithelial cell growth medium (AECGM), dual-SMAD inhibitor (DSI)-enriched AECGM, and PneumaCult Ex plus (PEx+). Analysis through RNA sequencing, immune assays, and impedance measurements revealed that PEx+ media significantly drove cell proliferation and a broad proinflammatory phenotype in BCs. In contrast, BCs expanded in AECGM and displayed increased expression of structural and extracellular matrix components at higher passage. AECGM increased expression of some cytokines at high passage, whereas DSI suppressed inflammation implicating the involvement TGF-β in BC inflammatory processes. Differentiation capacity of BCs declined with time in culture irrespective of expansion media. This was associated with an increase in PLUNC expressing secretory cells in AECGM and PEx+ media consistent with the known immune modulatory role of PLUNC in the airways. These findings highlight the profound impact of media conditions on inflammatory niche established by, and function of, in vitro expanded BCs. The broad proinflammatory phenotype driven by PEx+ media, in particular, should be considered in the development of cell-based models for airway diseases and therapeutic applications.<b>NEW & NOTEWORTHY</b> Airway basal cells, vital for airway regeneration and potential therapies, show significant changes based on culture conditions. Our study reveals that media composition and culture duration greatly affect basal cell properties with profound changes in the proinflammatory phenotype and extracellular matrix deposition driven by changes in growth conditions. These results underscore the critical impact of culture conditions on BC phenotype, influencing cell-based models for airway disease research and therapy.</p>","PeriodicalId":7593,"journal":{"name":"American journal of physiology. Lung cellular and molecular physiology","volume":" ","pages":"L538-L553"},"PeriodicalIF":3.6,"publicationDate":"2025-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12261264/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143472233","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}