Pub Date : 2024-07-30DOI: 10.1152/ajplung.00350.2023
Katherine D Wick, Lianne Siegel, Cathryn Oldmixon, Jens D Lundgren, B Taylor Thompson, Chayse Jones, Carolyn Leroux, Michael A Matthay
The soluble receptor for advanced glycation end-products (sRAGE) is a marker of alveolar type I cell injury associated with outcomes COVID-19 pneumonia. How plasma sRAGE changes over time and whether it remains associated with long-term clinical outcomes beyond a single measurement in COVID-19 has not been well-studied. We studied two cohorts in randomized clinical trials of monoclonal antibody treatment for COVID-19 (bamlanivimab and tixagevimab/cilgavimab). We first studied the association between baseline plasma sRAGE and 90-day clinical outcomes, which had been previously demonstrated in the bamlanivimab cohort, among hospitalized patients with COVID-19 supported with high flow nasal oxygen (HFNO) or non-invasive ventilation (NIV) in the tixagevimab/cilgavimab study. Next, we investigated the relationship between day 3 sRAGE and 90-day outcomes and how plasma sRAGE changes over the first 3 days of hospitalization in both clinical trial cohorts. We found that plasma sRAGE in the highest quartile in the HFNO/NIV participants in the tixagevimab/cilgavimab trial was associated with a significantly lower rate of 90-day sustained recovery (recovery rate ratio 0.31, 95% CI 0.14-0.71, p=0.005) and with a significantly higher rate of 90-day mortality (HR 2.49, 95% CI 1.15-5.43, p = 0.021) compared with the lower three quartiles. Day 3 plasma sRAGE in both clinical trial cohorts remained associated with 90-day clinical outcomes. The trajectory of sRAGE was not influenced by treatment assignment. Our results indicate that plasma sRAGE is a valuable prognostic marker in COVID-19 up to three days after initial hospital presentation.
{"title":"Longitudinal Importance of the Soluble Receptor for Advanced Glycation End-Products in Non-intubated Hospitalized Patients with COVID-19 Pneumonia.","authors":"Katherine D Wick, Lianne Siegel, Cathryn Oldmixon, Jens D Lundgren, B Taylor Thompson, Chayse Jones, Carolyn Leroux, Michael A Matthay","doi":"10.1152/ajplung.00350.2023","DOIUrl":"https://doi.org/10.1152/ajplung.00350.2023","url":null,"abstract":"<p><p>The soluble receptor for advanced glycation end-products (sRAGE) is a marker of alveolar type I cell injury associated with outcomes COVID-19 pneumonia. How plasma sRAGE changes over time and whether it remains associated with long-term clinical outcomes beyond a single measurement in COVID-19 has not been well-studied. We studied two cohorts in randomized clinical trials of monoclonal antibody treatment for COVID-19 (bamlanivimab and tixagevimab/cilgavimab). We first studied the association between baseline plasma sRAGE and 90-day clinical outcomes, which had been previously demonstrated in the bamlanivimab cohort, among hospitalized patients with COVID-19 supported with high flow nasal oxygen (HFNO) or non-invasive ventilation (NIV) in the tixagevimab/cilgavimab study. Next, we investigated the relationship between day 3 sRAGE and 90-day outcomes and how plasma sRAGE changes over the first 3 days of hospitalization in both clinical trial cohorts. We found that plasma sRAGE in the highest quartile in the HFNO/NIV participants in the tixagevimab/cilgavimab trial was associated with a significantly lower rate of 90-day sustained recovery (recovery rate ratio 0.31, 95% CI 0.14-0.71, p=0.005) and with a significantly higher rate of 90-day mortality (HR 2.49, 95% CI 1.15-5.43, p = 0.021) compared with the lower three quartiles. Day 3 plasma sRAGE in both clinical trial cohorts remained associated with 90-day clinical outcomes. The trajectory of sRAGE was not influenced by treatment assignment. Our results indicate that plasma sRAGE is a valuable prognostic marker in COVID-19 up to three days after initial hospital presentation.</p>","PeriodicalId":7593,"journal":{"name":"American journal of physiology. Lung cellular and molecular physiology","volume":null,"pages":null},"PeriodicalIF":3.6,"publicationDate":"2024-07-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141791680","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}
Pub Date : 2024-07-16DOI: 10.1152/ajplung.00198.2024
Thaís C F Menezes, Dara C Fonseca Balladares, Kevin Nolan, Brian B Graham
{"title":"Two hits strike out causing persistent pulmonary hypertension in mice.","authors":"Thaís C F Menezes, Dara C Fonseca Balladares, Kevin Nolan, Brian B Graham","doi":"10.1152/ajplung.00198.2024","DOIUrl":"10.1152/ajplung.00198.2024","url":null,"abstract":"","PeriodicalId":7593,"journal":{"name":"American journal of physiology. Lung cellular and molecular physiology","volume":null,"pages":null},"PeriodicalIF":3.6,"publicationDate":"2024-07-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141619060","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}
Pub Date : 2024-07-01Epub Date: 2024-05-14DOI: 10.1152/ajplung.00091.2024
Miguel A Hernandez-Lara, Joshua Richard, Deepak A Deshpande
Signal transduction by G protein-coupled receptors (GPCRs), receptor tyrosine kinases (RTKs) and immunoreceptors converge at the activation of phospholipase C (PLC) for the hydrolysis of phosphatidylinositol 4,5-bisphosphate (PIP2) into inositol 1,4,5-trisphosphate (IP3) and diacylglycerol (DAG). This is a point for second-messenger bifurcation where DAG via protein kinase C (PKC) and IP3 via calcium activate distinct protein targets and regulate cellular functions. IP3 signaling is regulated by multiple calcium influx and efflux proteins involved in calcium homeostasis. A family of lipid kinases belonging to DAG kinases (DGKs) converts DAG to phosphatidic acid (PA), negatively regulating DAG signaling and pathophysiological functions. PA, through a series of biochemical reactions, is recycled to produce new molecules of PIP2. Therefore, DGKs act as a central switch in terminating DAG signaling and resynthesis of membrane phospholipids precursor. Interestingly, calcium and PKC regulate the activation of α and ζ isoforms of DGK that are predominantly expressed in airway and immune cells. Thus, DGK forms a feedback and feedforward control point and plays a crucial role in fine-tuning phospholipid stoichiometry, signaling, and functions. In this review, we discuss the previously underappreciated complex and intriguing DAG/DGK-driven mechanisms in regulating cellular functions associated with asthma, such as contraction and proliferation of airway smooth muscle (ASM) cells and inflammatory activation of immune cells. We highlight the benefits of manipulating DGK activity in mitigating salient features of asthma pathophysiology and shed light on DGK as a molecule of interest for heterogeneous diseases such as asthma.
G 蛋白偶联受体 (GPCR)、受体酪氨酸激酶 (RTK) 和免疫感受器的信号转导汇聚到磷脂酶 C (PLC) 的激活处,以将磷脂酰肌醇 4,5- 二磷酸 (PIP2) 水解为肌醇 1,4,5- 三磷酸 (IP3) 和二酰甘油 (DAG)。这是第二信使的分叉点,DAG 通过蛋白激酶 C (PKC) 和 IP3 通过钙激活不同的蛋白质靶点,并调节细胞功能。IP3 信号由多种参与钙平衡的钙流入和流出蛋白调节。属于 DAG 激酶(DGK)的脂质激酶家族可将 DAG 转化为磷脂酸(PA),从而对 DAG 信号转导和病理生理功能进行负向调节。PA 通过一系列生化反应循环生成新的 PIP2 分子。因此,DGKs 是终止 DAG 信号传导和膜磷脂前体再合成的中心开关。有趣的是,钙和 PKC 可调节主要在气道和免疫细胞中表达的 DGK 的 a 和 z 异构体的活化。因此,DGK 形成了一个反馈和前馈控制点,在微调磷脂的配比、信号传递和功能方面发挥着至关重要的作用。在这篇综述中,我们讨论了以前未被充分认识的复杂而有趣的 DAG/DGK 驱动机制,这些机制可调节与哮喘有关的细胞功能,如气道平滑肌(ASM)细胞的收缩和增殖以及免疫细胞的炎症激活。我们强调了操纵 DGK 活性对减轻哮喘病理生理学显著特征的益处,并阐明了 DGK 作为一种分子对哮喘等异质性疾病的重要性。
{"title":"Diacylglycerol kinase is a keystone regulator of signaling relevant to the pathophysiology of asthma.","authors":"Miguel A Hernandez-Lara, Joshua Richard, Deepak A Deshpande","doi":"10.1152/ajplung.00091.2024","DOIUrl":"10.1152/ajplung.00091.2024","url":null,"abstract":"<p><p>Signal transduction by G protein-coupled receptors (GPCRs), receptor tyrosine kinases (RTKs) and immunoreceptors converge at the activation of phospholipase C (PLC) for the hydrolysis of phosphatidylinositol 4,5-bisphosphate (PIP<sub>2</sub>) into inositol 1,4,5-trisphosphate (IP<sub>3</sub>) and diacylglycerol (DAG). This is a point for second-messenger bifurcation where DAG via protein kinase C (PKC) and IP<sub>3</sub> via calcium activate distinct protein targets and regulate cellular functions. IP<sub>3</sub> signaling is regulated by multiple calcium influx and efflux proteins involved in calcium homeostasis. A family of lipid kinases belonging to DAG kinases (DGKs) converts DAG to phosphatidic acid (PA), negatively regulating DAG signaling and pathophysiological functions. PA, through a series of biochemical reactions, is recycled to produce new molecules of PIP<sub>2</sub>. Therefore, DGKs act as a central switch in terminating DAG signaling and resynthesis of membrane phospholipids precursor. Interestingly, calcium and PKC regulate the activation of α and ζ isoforms of DGK that are predominantly expressed in airway and immune cells. Thus, DGK forms a feedback and feedforward control point and plays a crucial role in fine-tuning phospholipid stoichiometry, signaling, and functions. In this review, we discuss the previously underappreciated complex and intriguing DAG/DGK-driven mechanisms in regulating cellular functions associated with asthma, such as contraction and proliferation of airway smooth muscle (ASM) cells and inflammatory activation of immune cells. We highlight the benefits of manipulating DGK activity in mitigating salient features of asthma pathophysiology and shed light on DGK as a molecule of interest for heterogeneous diseases such as asthma.</p>","PeriodicalId":7593,"journal":{"name":"American journal of physiology. Lung cellular and molecular physiology","volume":null,"pages":null},"PeriodicalIF":3.6,"publicationDate":"2024-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11380957/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140915641","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}
Pub Date : 2024-07-01Epub Date: 2024-05-07DOI: 10.1152/ajplung.00241.2023
Y Jane Choi, Ellen Williams, Mar Janna Dahl, Sebastian E Amos, Christopher James, Angelo P Bautista, Veena Kurup, Gabrielle C Musk, Helen Kershaw, Peter G Arthur, Anthony Kicic, Yu Suk Choi, Jessica R Terrill, J Jane Pillow
Chorioamnionitis is a common antecedent of preterm birth and induces inflammation and oxidative stress in the fetal lungs. Reducing inflammation and oxidative stress in the fetal lungs may improve respiratory outcomes in preterm infants. Creatine is an organic acid with known anti-inflammatory and antioxidant properties. The objective of the study was to evaluate the efficacy of direct fetal creatine supplementation to reduce inflammation and oxidative stress in fetal lungs arising from an in utero proinflammatory stimulus. Fetal lambs (n = 51) were instrumented at 90 days gestation to receive a continuous infusion of creatine monohydrate (6 mg·kg-1·h-1) or saline for 17 days. Maternal chorioamnionitis was induced with intra-amniotic lipopolysaccharide (LPS; 1 mg, O55:H6) or saline 7 days before delivery at 110 days gestation. Tissue creatine content was assessed with capillary electrophoresis, and inflammatory markers were analyzed with Luminex Magpix and immunohistochemistry. Oxidative stress was measured as the level of protein thiol oxidation. The effects of LPS and creatine were analyzed using a two-way ANOVA. Fetal creatine supplementation increased lung creatine content by 149% (PCr < 0.0001) and had no adverse effects on lung morphology. LPS-exposed groups showed increased levels of interleukin-8 in the bronchoalveolar lavage (PLPS < 0.0001) and increased levels of CD45+ leukocytes (PLPS < 0.0001) and MPO+ (PLPS < 0.0001) cells in the lung parenchyma. Creatine supplementation significantly reduced the levels of CD45+ (PCr = 0.045) and MPO+ cells (PCr = 0.012) in the lungs and reduced thiol oxidation in plasma (PCr < 0.01) and lung tissue (PCr = 0.02). In conclusion, fetal creatine supplementation reduced markers of inflammation and oxidative stress in the fetal lungs arising from chorioamnionitis.NEW & NOTEWORTHY We evaluated the effect of antenatal creatine supplementation to reduce pulmonary inflammation and oxidative stress in the fetal lamb lungs arising from lipopolysaccharide (LPS)-induced chorioamnionitis. Fetal creatine supplementation increased lung creatine content and had no adverse effects on systemic fetal physiology and overall lung architecture. Importantly, fetuses that received creatine had significantly lower levels of inflammation and oxidative stress in the lungs, suggesting an anti-inflammatory and antioxidant benefit of creatine.
{"title":"Antenatal creatine supplementation reduces persistent fetal lung inflammation and oxidative stress in an ovine model of chorioamnionitis.","authors":"Y Jane Choi, Ellen Williams, Mar Janna Dahl, Sebastian E Amos, Christopher James, Angelo P Bautista, Veena Kurup, Gabrielle C Musk, Helen Kershaw, Peter G Arthur, Anthony Kicic, Yu Suk Choi, Jessica R Terrill, J Jane Pillow","doi":"10.1152/ajplung.00241.2023","DOIUrl":"10.1152/ajplung.00241.2023","url":null,"abstract":"<p><p>Chorioamnionitis is a common antecedent of preterm birth and induces inflammation and oxidative stress in the fetal lungs. Reducing inflammation and oxidative stress in the fetal lungs may improve respiratory outcomes in preterm infants. Creatine is an organic acid with known anti-inflammatory and antioxidant properties. The objective of the study was to evaluate the efficacy of direct fetal creatine supplementation to reduce inflammation and oxidative stress in fetal lungs arising from an in utero proinflammatory stimulus. Fetal lambs (<i>n</i> = 51) were instrumented at 90 days gestation to receive a continuous infusion of creatine monohydrate (6 mg·kg<sup>-1</sup>·h<sup>-1</sup>) or saline for 17 days. Maternal chorioamnionitis was induced with intra-amniotic lipopolysaccharide (LPS; 1 mg, O55:H6) or saline 7 days before delivery at 110 days gestation. Tissue creatine content was assessed with capillary electrophoresis, and inflammatory markers were analyzed with Luminex Magpix and immunohistochemistry. Oxidative stress was measured as the level of protein thiol oxidation. The effects of LPS and creatine were analyzed using a two-way ANOVA. Fetal creatine supplementation increased lung creatine content by 149% (<i>P</i><sub>Cr</sub> < 0.0001) and had no adverse effects on lung morphology. LPS-exposed groups showed increased levels of interleukin-8 in the bronchoalveolar lavage (<i>P</i><sub>LPS</sub> < 0.0001) and increased levels of CD45<sup>+</sup> leukocytes (<i>P</i><sub>LPS</sub> < 0.0001) and MPO<sup>+</sup> (<i>P</i><sub>LPS</sub> < 0.0001) cells in the lung parenchyma. Creatine supplementation significantly reduced the levels of CD45<sup>+</sup> (<i>P</i><sub>Cr</sub> = 0.045) and MPO<sup>+</sup> cells (<i>P</i><sub>Cr</sub> = 0.012) in the lungs and reduced thiol oxidation in plasma (<i>P</i><sub>Cr</sub> < 0.01) and lung tissue (<i>P</i><sub>Cr</sub> = 0.02). In conclusion, fetal creatine supplementation reduced markers of inflammation and oxidative stress in the fetal lungs arising from chorioamnionitis.<b>NEW & NOTEWORTHY</b> We evaluated the effect of antenatal creatine supplementation to reduce pulmonary inflammation and oxidative stress in the fetal lamb lungs arising from lipopolysaccharide (LPS)-induced chorioamnionitis. Fetal creatine supplementation increased lung creatine content and had no adverse effects on systemic fetal physiology and overall lung architecture. Importantly, fetuses that received creatine had significantly lower levels of inflammation and oxidative stress in the lungs, suggesting an anti-inflammatory and antioxidant benefit of creatine.</p>","PeriodicalId":7593,"journal":{"name":"American journal of physiology. Lung cellular and molecular physiology","volume":null,"pages":null},"PeriodicalIF":3.6,"publicationDate":"2024-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140854955","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}
Pub Date : 2024-07-01Epub Date: 2024-05-21DOI: 10.1152/ajplung.00264.2023
Maunick Lefin Koloko Ngassie, Li Y Drake, Benjamin B Roos, Amanda Koenig-Kappes, Christina M Pabelick, Reinoud Gosens, Corry-Anke Brandsma, Janette K Burgess, Y S Prakash
Loss of proteostasis and cellular senescence have been previously established as characteristics of aging; however, their interaction in the context of lung aging and potential contributions to aging-associated lung remodeling remains understudied. In this study, we aimed to characterize endoplasmic reticulum (ER) stress response, cellular senescence, and their interaction in relation to extracellular matrix (ECM) production in lung fibroblasts from young (25-45 yr) and old (>60 yr) humans. Fibroblasts from young and old patients without significant preexisting lung disease were exposed to vehicle, MG132, etoposide, or salubrinal. Afterward, cells and cell lysates or supernatants were analyzed for ER stress, cellular senescence, and ECM changes using protein analysis, proliferation assay, and senescence-associated beta-galactosidase (SA-β-Gal) staining. At baseline, fibroblasts from aging individuals showed increased levels of ER stress (ATF6 and PERK), senescence (p21 and McL-1), and ECM marker (COL1A1) compared to those from young individuals. Upon ER stress induction and etoposide exposure, fibroblasts showed an increase in senescence (SA-β-Gal, p21, and Cav-1), ER stress (PERK), and ECM markers (COL1A1 and LUM) compared to vehicle. Additionally, IL-6 and IL-8 levels were increased in the supernatants of MG132- and etoposide-treated fibroblasts, respectively. Finally, the ER stress inhibitor salubrinal decreased the expression of p21 compared to vehicle and MG132 treatments; however, salubrinal inhibited COL1A1 but not p21 expression in MG132-treated fibroblasts. Our study suggests that ER stress response plays an important role in establishment and maintenance of a senescence phenotype in lung fibroblasts and therefore contributes to altered remodeling in the aging lung.NEW & NOTEWORTHY The current study establishes functional links between endoplasmic reticulum (ER) stress and cellular senescence per se in the specific context of aging human lung fibroblasts. Recognizing that the process of aging per se is complex, modulated by the myriad of lifelong and environmental exposures, it is striking to note that chronic ER stress may play a crucial role in the establishment and maintenance of cellular senescence in lung fibroblasts.
{"title":"Endoplasmic reticulum stress-induced senescence in human lung fibroblasts.","authors":"Maunick Lefin Koloko Ngassie, Li Y Drake, Benjamin B Roos, Amanda Koenig-Kappes, Christina M Pabelick, Reinoud Gosens, Corry-Anke Brandsma, Janette K Burgess, Y S Prakash","doi":"10.1152/ajplung.00264.2023","DOIUrl":"10.1152/ajplung.00264.2023","url":null,"abstract":"<p><p>Loss of proteostasis and cellular senescence have been previously established as characteristics of aging; however, their interaction in the context of lung aging and potential contributions to aging-associated lung remodeling remains understudied. In this study, we aimed to characterize endoplasmic reticulum (ER) stress response, cellular senescence, and their interaction in relation to extracellular matrix (ECM) production in lung fibroblasts from young (25-45 yr) and old (>60 yr) humans. Fibroblasts from young and old patients without significant preexisting lung disease were exposed to vehicle, MG132, etoposide, or salubrinal. Afterward, cells and cell lysates or supernatants were analyzed for ER stress, cellular senescence, and ECM changes using protein analysis, proliferation assay, and senescence-associated beta-galactosidase (SA-β-Gal) staining. At baseline, fibroblasts from aging individuals showed increased levels of ER stress (ATF6 and PERK), senescence (p21 and McL-1), and ECM marker (COL1A1) compared to those from young individuals. Upon ER stress induction and etoposide exposure, fibroblasts showed an increase in senescence (SA-β-Gal, p21, and Cav-1), ER stress (PERK), and ECM markers (COL1A1 and LUM) compared to vehicle. Additionally, IL-6 and IL-8 levels were increased in the supernatants of MG132- and etoposide-treated fibroblasts, respectively. Finally, the ER stress inhibitor salubrinal decreased the expression of p21 compared to vehicle and MG132 treatments; however, salubrinal inhibited COL1A1 but not p21 expression in MG132-treated fibroblasts. Our study suggests that ER stress response plays an important role in establishment and maintenance of a senescence phenotype in lung fibroblasts and therefore contributes to altered remodeling in the aging lung.<b>NEW & NOTEWORTHY</b> The current study establishes functional links between endoplasmic reticulum (ER) stress and cellular senescence per se in the specific context of aging human lung fibroblasts. Recognizing that the process of aging per se is complex, modulated by the myriad of lifelong and environmental exposures, it is striking to note that chronic ER stress may play a crucial role in the establishment and maintenance of cellular senescence in lung fibroblasts.</p>","PeriodicalId":7593,"journal":{"name":"American journal of physiology. Lung cellular and molecular physiology","volume":null,"pages":null},"PeriodicalIF":3.6,"publicationDate":"2024-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11380945/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141070107","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}
Pub Date : 2024-07-01Epub Date: 2024-03-19DOI: 10.1152/ajplung.00127.2023
Miranda R Sun, Susana Gonzalez, Jason B Huang, Qiyuan Zhou, Arjun Cherukuri, Rohan Adavadkar, Hong-Li Yan, Shu-Han Sun, Guofei Zhou, J Usha Raj, Tianji Chen
We have reported previously that during hypoxia exposure, the expression of mature miR-17∼92 was first upregulated and then downregulated in pulmonary artery smooth muscle cells (PASMC) and in mouse lungs in vitro and in vivo. Here, we investigated the mechanisms regulating this biphasic expression of miR-17∼92 in PASMC in hypoxia. We measured the level of primary miR-17∼92 in PASMC during hypoxia exposure and found that short-term hypoxia exposure (3% O2, 6 h) induced the level of primary miR-17∼92, whereas long-term hypoxia exposure (3% O2, 24 h) decreased its level, suggesting a biphasic regulation of miR-17∼92 expression at the transcriptional level. We found that short-term hypoxia-induced upregulation of miR-17∼92 was hypoxia-inducible factor 1α (HIF1α) and E2F1 dependent. Two HIF1α binding sites on miR-17∼92 promoter were identified. We also found that long-term hypoxia-induced suppression of miR-17∼92 expression could be restored by silencing of p53. Mutation of the p53-binding sites in the miR-17∼92 promoter increased miR-17∼92 promoter activity in both normoxia and hypoxia. Our findings suggest that the biphasic transcriptional regulation of miR-17∼92 during hypoxia is controlled by HIF1/E2F1 and p53 in PASMC: during short-term hypoxia exposure, stabilization of HIF1 and induction of E2F1 induce the transcription of miR-17∼92, whereas during long-term hypoxia exposure, hyperphosphorylation of p53 suppresses the expression of miR-17∼92.NEW & NOTEWORTHY We showed that the biphasic transcriptional regulation of miR-17∼92 during hypoxia is controlled by two distinct mechanisms: during short-term hypoxia exposure, induction of HIF1 and E2F1 upregulates miR-17∼92. Longer hypoxia exposure induces hyperphosphorylation of p53 at ser15, which leads to its binding to miR-17∼92 promoter and inhibition of its expression. Our findings provide novel insights into the spatiotemporal regulation of miR-17∼92 that may play a role in the development of human lung diseases including pulmonary hypertension (PH).
{"title":"Biphasic regulation of miR-17∼92 transcription during hypoxia: roles of HIF1 and p53 hyperphosphorylation at ser15.","authors":"Miranda R Sun, Susana Gonzalez, Jason B Huang, Qiyuan Zhou, Arjun Cherukuri, Rohan Adavadkar, Hong-Li Yan, Shu-Han Sun, Guofei Zhou, J Usha Raj, Tianji Chen","doi":"10.1152/ajplung.00127.2023","DOIUrl":"10.1152/ajplung.00127.2023","url":null,"abstract":"<p><p>We have reported previously that during hypoxia exposure, the expression of mature miR-17∼92 was first upregulated and then downregulated in pulmonary artery smooth muscle cells (PASMC) and in mouse lungs in vitro and in vivo. Here, we investigated the mechanisms regulating this biphasic expression of miR-17∼92 in PASMC in hypoxia. We measured the level of primary miR-17∼92 in PASMC during hypoxia exposure and found that short-term hypoxia exposure (3% O<sub>2</sub>, 6 h) induced the level of primary miR-17∼92, whereas long-term hypoxia exposure (3% O<sub>2</sub>, 24 h) decreased its level, suggesting a biphasic regulation of miR-17∼92 expression at the transcriptional level. We found that short-term hypoxia-induced upregulation of miR-17∼92 was hypoxia-inducible factor 1α (HIF1α) and E2F1 dependent. Two HIF1α binding sites on miR-17∼92 promoter were identified. We also found that long-term hypoxia-induced suppression of miR-17∼92 expression could be restored by silencing of p53. Mutation of the p53-binding sites in the miR-17∼92 promoter increased miR-17∼92 promoter activity in both normoxia and hypoxia. Our findings suggest that the biphasic transcriptional regulation of miR-17∼92 during hypoxia is controlled by HIF1/E2F1 and p53 in PASMC: during short-term hypoxia exposure, stabilization of HIF1 and induction of E2F1 induce the transcription of miR-17∼92, whereas during long-term hypoxia exposure, hyperphosphorylation of p53 suppresses the expression of miR-17∼92.<b>NEW & NOTEWORTHY</b> We showed that the biphasic transcriptional regulation of miR-17∼92 during hypoxia is controlled by two distinct mechanisms: during short-term hypoxia exposure, induction of HIF1 and E2F1 upregulates miR-17∼92. Longer hypoxia exposure induces hyperphosphorylation of p53 at ser15, which leads to its binding to miR-17∼92 promoter and inhibition of its expression. Our findings provide novel insights into the spatiotemporal regulation of miR-17∼92 that may play a role in the development of human lung diseases including pulmonary hypertension (PH).</p>","PeriodicalId":7593,"journal":{"name":"American journal of physiology. Lung cellular and molecular physiology","volume":null,"pages":null},"PeriodicalIF":3.6,"publicationDate":"2024-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11380943/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140157404","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}
Pub Date : 2024-07-01Epub Date: 2024-05-07DOI: 10.1152/ajplung.00066.2024
Melissa E Skibba, Allan R Brasier
The mechanisms how aeroallergens induce sensitization are incompletely understood. The house dust mite (HDM) Dermatophagoides pteronyssius (Der p) is a ubiquitous aeroallergen that represents a major cause of allergic rhinitis and asthma. Herein, we tested whether HDM-induced aeroallergen exposure sensitivity is caused by the innate-immune response in small airway epithelial cells. HDM exposure is a rapid activator of NF-κB/RelA in the Secretoglobin (Scgb1a1+) lineage associated with upregulation of NF-κB/RelA-dependent markers of epithelial plasticity. To determine the effect of epithelial NF-κB signaling, NF-κB was depleted in a tamoxifen (TMX)-inducible Scgb1a1-CreERTM mouse within a CL57B/L6 background. Corn oil or TMX-treated/RelA-depleted [RelA knockdown (KD)] mice were repetitively exposed to airway HDM challenges to induce airway hyperresponsiveness (AHR). Strikingly, we observed that HDM induces hallmarks of epithelial plasticity through upregulation of the mesenchymal core factors SNAI1 and ZEB1 and production of metalloproteinase (MMP)9 that are RelA-dependent. Downstream, HDM-induced mucous metaplasia, Th2 polarization, allergen sensitivity, and airway hyperreactivity were all reduced in the RelA-depleted mice. Mechanistically, HDM-induced functional and structural barrier disruption was dependent on RelA signaling and associated with active MMP secretion into the bronchoalveolar lavage fluid. To establish the role of MMP2/9 in barrier disruption, we observe that a small-molecule MMP inhibitor (SB-3CT) blocked HDM-induced barrier disruption and activation of plasticity in naïve wild-type (WT) mice. Loss of functional barrier was associated with MMP disruption of zona occludens (ZO)-1 containing adherens junctions. Overall, this data indicates that host innate signaling in the Scgb1a1+ progenitors is directly linked to epithelial plasticity, MMP9 secretion, and enhanced barrier permeability that allows allergen penetration, sensitization producing allergic asthma (AA) in vivo. We propose that maintenance of epithelial integrity may reduce allergic sensitization and AA.NEW & NOTEWORTHY Allergic asthma from house dust mite (HDM) allergy causes substantial morbidity. This study examines the dynamic changes in small airway epithelial cells in a mouse model of HDM exposure. Our findings indicate that NF-κB/RelA signaling mediates matrix metalloproteinase production, disrupting the epithelial barrier resulting in allergic sensitization. Our findings bring new insight into mechanisms for epithelial cell-state change in the allergen response, creating a potential therapeutic pathway for maintaining barrier function in asthma.
{"title":"NF-κB/RelA signaling in secretoglobin progenitors mediates plasticity and MMP-induced barrier disruption in house dust mite-induced allergic asthma.","authors":"Melissa E Skibba, Allan R Brasier","doi":"10.1152/ajplung.00066.2024","DOIUrl":"10.1152/ajplung.00066.2024","url":null,"abstract":"<p><p>The mechanisms how aeroallergens induce sensitization are incompletely understood. The house dust mite (HDM) <i>Dermatophagoides pteronyssius</i> (Der p) is a ubiquitous aeroallergen that represents a major cause of allergic rhinitis and asthma. Herein, we tested whether HDM-induced aeroallergen exposure sensitivity is caused by the innate-immune response in small airway epithelial cells. HDM exposure is a rapid activator of NF-κB/RelA in the Secretoglobin (Scgb1a1+) lineage associated with upregulation of NF-κB/RelA-dependent markers of epithelial plasticity. To determine the effect of epithelial NF-κB signaling, NF-κB was depleted in a tamoxifen (TMX)-inducible <i>Scgb1a1</i>-CreER<sup>TM</sup> mouse within a CL57B/L6 background. Corn oil or TMX-treated/RelA-depleted [RelA knockdown (KD)] mice were repetitively exposed to airway HDM challenges to induce airway hyperresponsiveness (AHR). Strikingly, we observed that HDM induces hallmarks of epithelial plasticity through upregulation of the mesenchymal core factors SNAI1 and ZEB1 and production of metalloproteinase (MMP)9 that are RelA-dependent. Downstream, HDM-induced mucous metaplasia, Th2 polarization, allergen sensitivity, and airway hyperreactivity were all reduced in the RelA-depleted mice. Mechanistically, HDM-induced functional and structural barrier disruption was dependent on RelA signaling and associated with active MMP secretion into the bronchoalveolar lavage fluid. To establish the role of MMP2/9 in barrier disruption, we observe that a small-molecule MMP inhibitor (SB-3CT) blocked HDM-induced barrier disruption and activation of plasticity in naïve wild-type (WT) mice. Loss of functional barrier was associated with MMP disruption of zona occludens (ZO)-1 containing adherens junctions. Overall, this data indicates that host innate signaling in the Scgb1a1+ progenitors is directly linked to epithelial plasticity, MMP9 secretion, and enhanced barrier permeability that allows allergen penetration, sensitization producing allergic asthma (AA) in vivo. We propose that maintenance of epithelial integrity may reduce allergic sensitization and AA.<b>NEW & NOTEWORTHY</b> Allergic asthma from house dust mite (HDM) allergy causes substantial morbidity. This study examines the dynamic changes in small airway epithelial cells in a mouse model of HDM exposure. Our findings indicate that NF-κB/RelA signaling mediates matrix metalloproteinase production, disrupting the epithelial barrier resulting in allergic sensitization. Our findings bring new insight into mechanisms for epithelial cell-state change in the allergen response, creating a potential therapeutic pathway for maintaining barrier function in asthma.</p>","PeriodicalId":7593,"journal":{"name":"American journal of physiology. Lung cellular and molecular physiology","volume":null,"pages":null},"PeriodicalIF":3.6,"publicationDate":"2024-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11380976/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140875594","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}
Pub Date : 2024-07-01Epub Date: 2024-05-07DOI: 10.1152/ajplung.00323.2023
Richard Zimmermann, Franziska Roeder, Clemens Ruppert, Bradford J Smith, Lars Knudsen
Mechanical ventilation can cause ventilation-induced lung injury (VILI). The concept of stress concentrations suggests that surfactant dysfunction-induced microatelectases might impose injurious stresses on adjacent, open alveoli and function as germinal centers for injury propagation. The aim of the present study was to quantify the histopathological pattern of VILI progression and to test the hypothesis that injury progresses at the interface between microatelectases and ventilated lung parenchyma during low-positive end-expiratory pressure (PEEP) ventilation. Bleomycin was used to induce lung injury with microatelectases in rats. Lungs were then mechanically ventilated for up to 6 h at PEEP = 1 cmH2O and compared with bleomycin-treated group ventilated protectively with PEEP = 5 cmH2O to minimize microatelectases. Lung mechanics were measured during ventilation. Afterward, lungs were fixed at end-inspiration or end-expiration for design-based stereology. Before VILI, bleomycin challenge reduced the number of open alveoli [N(alvair,par)] by 29%. No differences between end-inspiration and end-expiration were observed. Collapsed alveoli clustered in areas with a radius of up to 56 µm. After PEEP = 5 cmH2O ventilation for 6 h, N(alvair,par) remained stable while PEEP = 1 cmH2O ventilation led to an additional loss of aerated alveoli by 26%, mainly due to collapse, with a small fraction partly edema filled. Alveolar loss strongly correlated to worsening of tissue elastance, quasistatic compliance, and inspiratory capacity. The radius of areas of collapsed alveoli increased to 94 µm, suggesting growth of the microatelectases. These data provide evidence that alveoli become unstable in neighborhood of microatelectases, which most likely occurs due to stress concentration-induced local vascular leak and surfactant dysfunction.NEW & NOTEWORTHY Low-volume mechanical ventilation in the presence of high surface tension-induced microatelectases leads to the degradation of lung mechanical function via the progressive loss of alveoli. Microatelectases grow at the interfaces of collapsed and open alveoli. Here, stress concentrations might cause injury and alveolar instability. Accumulation of small amounts of alveolar edema can be found in a fraction of partly collapsed alveoli but, in this model, alveolar flooding is not a major driver for degradation of lung mechanics.
{"title":"Low-volume ventilation of preinjured lungs degrades lung function via stress concentration and progressive alveolar collapse.","authors":"Richard Zimmermann, Franziska Roeder, Clemens Ruppert, Bradford J Smith, Lars Knudsen","doi":"10.1152/ajplung.00323.2023","DOIUrl":"10.1152/ajplung.00323.2023","url":null,"abstract":"<p><p>Mechanical ventilation can cause ventilation-induced lung injury (VILI). The concept of stress concentrations suggests that surfactant dysfunction-induced microatelectases might impose injurious stresses on adjacent, open alveoli and function as germinal centers for injury propagation. The aim of the present study was to quantify the histopathological pattern of VILI progression and to test the hypothesis that injury progresses at the interface between microatelectases and ventilated lung parenchyma during low-positive end-expiratory pressure (PEEP) ventilation. Bleomycin was used to induce lung injury with microatelectases in rats. Lungs were then mechanically ventilated for up to 6 h at PEEP = 1 cmH<sub>2</sub>O and compared with bleomycin-treated group ventilated protectively with PEEP = 5 cmH<sub>2</sub>O to minimize microatelectases. Lung mechanics were measured during ventilation. Afterward, lungs were fixed at end-inspiration or end-expiration for design-based stereology. Before VILI, bleomycin challenge reduced the number of open alveoli [N(alvair,par)] by 29%. No differences between end-inspiration and end-expiration were observed. Collapsed alveoli clustered in areas with a radius of up to 56 µm. After PEEP = 5 cmH<sub>2</sub>O ventilation for 6 h, N(alvair,par) remained stable while PEEP = 1 cmH<sub>2</sub>O ventilation led to an additional loss of aerated alveoli by 26%, mainly due to collapse, with a small fraction partly edema filled. Alveolar loss strongly correlated to worsening of tissue elastance, quasistatic compliance, and inspiratory capacity. The radius of areas of collapsed alveoli increased to 94 µm, suggesting growth of the microatelectases. These data provide evidence that alveoli become unstable in neighborhood of microatelectases, which most likely occurs due to stress concentration-induced local vascular leak and surfactant dysfunction.<b>NEW & NOTEWORTHY</b> Low-volume mechanical ventilation in the presence of high surface tension-induced microatelectases leads to the degradation of lung mechanical function via the progressive loss of alveoli. Microatelectases grow at the interfaces of collapsed and open alveoli. Here, stress concentrations might cause injury and alveolar instability. Accumulation of small amounts of alveolar edema can be found in a fraction of partly collapsed alveoli but, in this model, alveolar flooding is not a major driver for degradation of lung mechanics.</p>","PeriodicalId":7593,"journal":{"name":"American journal of physiology. Lung cellular and molecular physiology","volume":null,"pages":null},"PeriodicalIF":3.6,"publicationDate":"2024-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140849716","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}
Pub Date : 2024-07-01Epub Date: 2024-05-21DOI: 10.1152/ajplung.00274.2023
Afzaal Nadeem Mohammed, Fatemeh Kohram, Ying-Wei Lan, Enhong Li, Olena A Kolesnichenko, Tanya V Kalin, Vladimir V Kalinichenko
Bronchopulmonary dysplasia (BPD) is a severe complication of preterm births, which develops due to exposure to supplemental oxygen and mechanical ventilation. Published studies demonstrated that the number of endothelial progenitor cells (EPC) is decreased in mouse and human BPD lungs and that adoptive transfer of EPC is an effective approach in reversing the hyperoxia-induced lung damage in mouse model of BPD. Recent advancements in macrophage biology identified the specific subtypes of circulating and resident macrophages mediating the developmental and regenerative functions in the lungs. Several studies reported the successful application of macrophage therapy in accelerating the regenerative capacity of damaged tissues and enhancing the therapeutic efficacy of other transplantable progenitor cells. In the present study, we explored the efficacy of combined cell therapy with EPC and resident alveolar macrophages (rAM) in hyperoxia-induced BPD mouse model. rAM and EPC were purified from neonatal mouse lungs and were used for adoptive transfer to the recipient neonatal mice exposed to hyperoxia. Adoptive transfer of rAM alone did not result in engraftment of donor rAM into the lung tissue but increased the mRNA level and protein concentration of proangiogenic CXCL12 chemokine in recipient mouse lungs. Depletion of rAM by chlodronate-liposomes decreased the retention of donor EPC after their transplantation into hyperoxia-injured lungs. Adoptive transfer of rAM in combination with EPC enhanced the therapeutic efficacy of EPC as evidenced by increased retention of EPC, increased capillary density, improved arterial oxygenation, and alveolarization in hyperoxia-injured lungs. Dual therapy with EPC and rAM has promise in human BPD.NEW & NOTEWORTHY Recent studies demonstrated that transplantation of lung-resident endothelial progenitor cells (EPC) is an effective therapy in mouse model of bronchopulmonary dysplasia (BPD). However, key factors regulating the efficacy of EPC are unknown. Herein, we demonstrate that transplantation of tissue-resident alveolar macrophages (rAM) increases CXCL12 expression in neonatal mouse lungs. rAM are required for retention of donor EPC in hyperoxia-injured lungs. Co-transplantation of rAM and EPC improves the efficacy of EPC therapy in mouse BPD model.
{"title":"Transplantation of alveolar macrophages improves the efficacy of endothelial progenitor cell therapy in mouse model of bronchopulmonary dysplasia.","authors":"Afzaal Nadeem Mohammed, Fatemeh Kohram, Ying-Wei Lan, Enhong Li, Olena A Kolesnichenko, Tanya V Kalin, Vladimir V Kalinichenko","doi":"10.1152/ajplung.00274.2023","DOIUrl":"10.1152/ajplung.00274.2023","url":null,"abstract":"<p><p>Bronchopulmonary dysplasia (BPD) is a severe complication of preterm births, which develops due to exposure to supplemental oxygen and mechanical ventilation. Published studies demonstrated that the number of endothelial progenitor cells (EPC) is decreased in mouse and human BPD lungs and that adoptive transfer of EPC is an effective approach in reversing the hyperoxia-induced lung damage in mouse model of BPD. Recent advancements in macrophage biology identified the specific subtypes of circulating and resident macrophages mediating the developmental and regenerative functions in the lungs. Several studies reported the successful application of macrophage therapy in accelerating the regenerative capacity of damaged tissues and enhancing the therapeutic efficacy of other transplantable progenitor cells. In the present study, we explored the efficacy of combined cell therapy with EPC and resident alveolar macrophages (rAM) in hyperoxia-induced BPD mouse model. rAM and EPC were purified from neonatal mouse lungs and were used for adoptive transfer to the recipient neonatal mice exposed to hyperoxia. Adoptive transfer of rAM alone did not result in engraftment of donor rAM into the lung tissue but increased the mRNA level and protein concentration of proangiogenic CXCL12 chemokine in recipient mouse lungs. Depletion of rAM by chlodronate-liposomes decreased the retention of donor EPC after their transplantation into hyperoxia-injured lungs. Adoptive transfer of rAM in combination with EPC enhanced the therapeutic efficacy of EPC as evidenced by increased retention of EPC, increased capillary density, improved arterial oxygenation, and alveolarization in hyperoxia-injured lungs. Dual therapy with EPC and rAM has promise in human BPD.<b>NEW & NOTEWORTHY</b> Recent studies demonstrated that transplantation of lung-resident endothelial progenitor cells (EPC) is an effective therapy in mouse model of bronchopulmonary dysplasia (BPD). However, key factors regulating the efficacy of EPC are unknown. Herein, we demonstrate that transplantation of tissue-resident alveolar macrophages (rAM) increases CXCL12 expression in neonatal mouse lungs. rAM are required for retention of donor EPC in hyperoxia-injured lungs. Co-transplantation of rAM and EPC improves the efficacy of EPC therapy in mouse BPD model.</p>","PeriodicalId":7593,"journal":{"name":"American journal of physiology. Lung cellular and molecular physiology","volume":null,"pages":null},"PeriodicalIF":3.6,"publicationDate":"2024-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11380942/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141075178","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}