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Wilkins AA, Schwarz B, Torres-Escobar A, Castore R, Landry L, Latimer B, Bohrnsen E, Bosio CM, Dragoi AM, Ivanov SS. The intracellular growth of the vacuolar pathogen Legionella pneumophila is dependent on the acyl chain composition of host membranes. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.11.19.567753. [PMID: 38045297 PMCID: PMC10690232 DOI: 10.1101/2023.11.19.567753] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/05/2023]
Abstract
Legionella pneumophila is an accidental human bacterial pathogen that infects and replicates within alveolar macrophages causing a severe atypical pneumonia known as Legionnaires' disease. As a prototypical vacuolar pathogen L. pneumophila establishes a unique endoplasmic reticulum (ER)-derived organelle within which bacterial replication takes place. Bacteria-derived proteins are deposited in the host cytosol and in the lumen of the pathogen-occupied vacuole via a type IVb (T4bSS) and a type II (T2SS) secretion system respectively. These secretion system effector proteins manipulate multiple host functions to facilitate intracellular survival of the bacteria. Subversion of host membrane glycerophospholipids (GPLs) by the internalized bacteria via distinct mechanisms feature prominently in trafficking and biogenesis of the Legionella -containing vacuole (LCV). Conventional GPLs composed of a glycerol backbone linked to a polar headgroup and esterified with two fatty acids constitute the bulk of membrane lipids in eukaryotic cells. The acyl chain composition of GPLs dictates phase separation of the lipid bilayer and therefore determines the physiochemical properties of biological membranes - such as membrane disorder, fluidity and permeability. In mammalian cells, fatty acids esterified in membrane GPLs are sourced endogenously from de novo synthesis or via internalization from the exogenous pool of lipids present in serum and other interstitial fluids. Here, we exploited the preferential utilization of exogenous fatty acids for GPL synthesis by macrophages to reprogram the acyl chain composition of host membranes and investigated its impact on LCV homeostasis and L. pneumophila intracellular replication. Using saturated fatty acids as well as cis - and trans - isomers of monounsaturated fatty acids we discovered that under conditions promoting lipid packing and membrane rigidification L. pneumophila intracellular replication was significantly reduced. Palmitoleic acid - a C16:1 monounsaturated fatty acid - that promotes membrane disorder when enriched in GPLs significantly increased bacterial replication within human and murine macrophages but not in axenic growth assays. Lipidome analysis of infected macrophages showed that treatment with exogenous palmitoleic acid resulted in membrane acyl chain reprogramming in a manner that promotes membrane disorder and live-cell imaging revealed that the consequences of increasing membrane disorder impinge on several LCV homeostasis parameters. Collectively, we provide experimental evidence that L. pneumophila replication within its intracellular niche is a function of the lipid bilayer disorder and hydrophobic thickness.
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Camdzic M, Aga DS, Atilla-Gokcumen GE. Cellular Lipidome Changes during Retinoic Acid (RA)-Induced Differentiation in SH-SY5Y Cells: A Comprehensive In Vitro Model for Assessing Neurotoxicity of Contaminants. ENVIRONMENT & HEALTH (WASHINGTON, D.C.) 2023; 1:110-120. [PMID: 37614295 PMCID: PMC10443778 DOI: 10.1021/envhealth.3c00022] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/27/2023] [Revised: 05/25/2023] [Accepted: 05/26/2023] [Indexed: 08/25/2023]
Abstract
The SH-SY5Y, neuroblastoma cell line, is a common in vitro model used to study physiological neuronal function and the neuronal response to different stimuli, including exposure to toxic chemicals. These cells can be differentiated to neuron-like cells by administration of various reagents, including retinoic acid or phorbol-12-myristate-13-acetate. Despite their common use, there is an incomplete understanding of the molecular changes that occur during differentiation. Therefore, there is a critical need to fully understand the molecular changes that occur during differentiation to properly study neurotoxicity in response to various environmental exposures. Previous studies have investigated the proteome and transcriptome during differentiation; however, the regulation of the cellular lipidome in this process is unexplored. In this work, we conducted liquid chromatography-mass spectrometry (LC-MS)-based untargeted lipidomics in undifferentiated and differentiated SH-SY5Y cells, induced by retinoic acid. We show that there are global differences between the cellular lipidomes of undifferentiated and differentiated cells. Out of thousands of features detected in positive and negative electrospray ionization modes, 44 species were identified that showed significant differences (p-value ≤0.05, fold change ≥2) in differentiated cells. Identification of these features combined with targeted lipidomics highlighted the accumulation of phospholipids, sterols, and sphingolipids during differentiation while triacylglycerols were depleted. These results provide important insights into lipid-related changes that occur during cellular differentiation of SH-5YSY cells and emphasize the need for the detailed characterization of biochemical differences that occur during differentiation while using this in vitro model for assessing ecological impacts of environmental pollutants.
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Affiliation(s)
- Michelle Camdzic
- Department of Chemistry, University at Buffalo, The State University of New
York (SUNY), Buffalo, New York 14260, United States
| | - Diana S. Aga
- Department of Chemistry, University at Buffalo, The State University of New
York (SUNY), Buffalo, New York 14260, United States
| | - G. Ekin Atilla-Gokcumen
- Department of Chemistry, University at Buffalo, The State University of New
York (SUNY), Buffalo, New York 14260, United States
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Du K, Sun L, Luo Z, Cao Y, Sun Q, Zhang K, Faizy A, Piomelli D, Lu X, Shan J, Yang Q. Reduced DMPC and PMPC in lung surfactant promote SARS-CoV-2 infection in obesity. Metabolism 2022; 131:155181. [PMID: 35311662 PMCID: PMC8930181 DOI: 10.1016/j.metabol.2022.155181] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/03/2021] [Revised: 02/18/2022] [Accepted: 03/14/2022] [Indexed: 12/16/2022]
Abstract
OBJECTIVE Obesity is an established risk factor for higher SARS-CoV-2 viral loads, severe COVID-19 pneumonia requiring hospitalization, and worse outcomes. However, the underlying mechanisms for the increased risk are not well understood. SARS-CoV-2 is a respiratory virus with the primary route of entry through the lungs, where the Spike protein of SARS-CoV-2 binds to the ACE2 receptor on pneumocytes. Lung surfactant produced by type II pneumocytes plays a major role in respiratory defense against infections. Surfactant predominantly contains lipids, especially phosphatidylcholines (PC), and obesity is characterized by aberrant lipid metabolism. We hypothesized that altered lipid composition in lung surfactant in obesity may promote SARS-CoV-2 infection, leading to severe COVID-19 disease. METHODS Lipidomic analysis of lung tissue and bronchoalveolar lavage fluid (BALF) was performed using LC-MS/MS. The effects of PCs on SARS-CoV-2 pseudovirus infection were studied in HEK293T cells with ACE2 overexpression and in Vero-E6 cells with endogenous ACE2 expression. For the cell-cell fusion assay, HEK293T-ACE2 and HEK293T expressing SARS-CoV-2 Spike/eGFP were used as the target and effector cells, respectively. RESULTS Lipidomic analysis revealed that myristic acid-containing dimyristoyl-PC (DMPC) and palmitoylmyristoyl-PC (PMPC) were reduced in lung tissue and BALF from high fat diet-induced obese mice. DMPC and PMPC markedly inhibited wild type and D614G mutant SARS-CoV-2 infection in HEK293T-ACE2 and Vero-E6 cells. Feeding obese mice with trimyristin, the triglycerides of myristic acid, increased DMPC and PMPC levels in lung surfactant. Lipid extract from BALF of trimyristin-treated obese mice mitigated the elevated wild type and D614G mutant SARS-CoV-2 infection. The inhibitory effects of DMPC and PMPC on SARS-CoV-2 infection were reversed by cholesterol. CONCLUSIONS The reduced DMPC and PMPC in lung surfactant may promote SARS-CoV-2 infection. Increasing DMPC and PMPC in lung surfactant could be an innovative strategy for preventing and treating severe COVID-19 disease in obesity.
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Affiliation(s)
- Kang Du
- Department of Medicine, Physiology and Biophysics, UCI Diabetes Center, University of California Irvine, Irvine, CA 92697, USA
| | - Ling Sun
- Institute of Pediatrics, Jiangsu Key Laboratory of Pediatric Respiratory Disease, Medical Metabolomics Center, Nanjing University of Chinese Medicine, Nanjing 210023, China
| | - Zichen Luo
- Institute of Pediatrics, Jiangsu Key Laboratory of Pediatric Respiratory Disease, Medical Metabolomics Center, Nanjing University of Chinese Medicine, Nanjing 210023, China
| | - Yang Cao
- Department of Medicine, Physiology and Biophysics, UCI Diabetes Center, University of California Irvine, Irvine, CA 92697, USA
| | - Qiushi Sun
- Department of Medicine, Physiology and Biophysics, UCI Diabetes Center, University of California Irvine, Irvine, CA 92697, USA
| | - Kangzhen Zhang
- Department of Medicine, Physiology and Biophysics, UCI Diabetes Center, University of California Irvine, Irvine, CA 92697, USA
| | - Ahmed Faizy
- Department of Anatomy and Neurobiology, University of California, Irvine, CA 92697-4625, USA; Department of Biological Chemistry, University of California, Irvine, CA 92697-4625, USA
| | - Daniele Piomelli
- Department of Anatomy and Neurobiology, University of California, Irvine, CA 92697-4625, USA; Department of Biological Chemistry, University of California, Irvine, CA 92697-4625, USA
| | - Xiang Lu
- Department of Geriatrics, Sir Run Run Shaw Hospital, Nanjing Medical University, Nanjing 211166, China
| | - Jinjun Shan
- Institute of Pediatrics, Jiangsu Key Laboratory of Pediatric Respiratory Disease, Medical Metabolomics Center, Nanjing University of Chinese Medicine, Nanjing 210023, China.
| | - Qin Yang
- Department of Medicine, Physiology and Biophysics, UCI Diabetes Center, University of California Irvine, Irvine, CA 92697, USA.
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Lysophosphatidylcholine Acyltransferase 1 Deficiency Promotes Pulmonary Emphysema via Apoptosis of Alveolar Epithelial Cells. Inflammation 2022; 45:1765-1779. [PMID: 35338433 DOI: 10.1007/s10753-022-01659-4] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2021] [Revised: 01/26/2022] [Accepted: 03/07/2022] [Indexed: 11/05/2022]
Abstract
Chronic obstructive pulmonary disease (COPD) is primarily caused by inhalation of cigarette smoke and is the third leading cause of death worldwide. Pulmonary surfactant, a complex of phospholipids and proteins, plays an essential role in respiration by reducing the surface tension in the alveoli. Lysophosphatidylcholine acyltransferase 1 (LPCAT1) is an enzyme that catalyzes the biosynthesis of surfactant lipids and is expressed in type 2 alveolar epithelial cells. Its dysfunction is suggested to be involved in various lung diseases; however, the relationship between LPCAT1 and COPD remains unclear. To investigate the role of LPCAT1 in the pathology of COPD, we analyzed an elastase-induced emphysema model using Lpcat1 knockout (KO) mice. In Lpcat1 KO mice, elastase-induced emphysema was significantly exacerbated with increased apoptotic cells, which was not ameliorated by supplementation with dipalmitoylphosphatidylcholine, which is a major component of the surfactant synthesized by LPCAT1. We subsequently evaluated the effects of cigarette smoking on primary human type 2 alveolar epithelial cells (hAEC2s) and found that cigarette smoke extract (CSE) downregulated the expression of Lpcat1. Furthermore, RNA sequencing analysis revealed that the apoptosis pathway was significantly enriched in CSE-treated primary hAEC2s. Finally, we downregulated the expression of Lpcat1 using small interfering RNA, which resulted in enhanced CSE-induced apoptosis in A549 cells. Taken together, cigarette smoke-induced downregulation of LPCAT1 can promote the exacerbation of pulmonary emphysema by increasing the susceptibility of alveolar epithelial cells to apoptosis, thereby suggesting that Lpcat1 is a novel therapeutic target for irreversible emphysema.
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Sun XW, Lin YN, Ding YJ, Li SQ, Li HP, Zhou JP, Zhang L, Shen JM, Li QY. Surfaxin attenuates PM2.5-induced airway inflammation via restoring surfactant proteins in rats exposed to cigarette smoke. ENVIRONMENTAL RESEARCH 2022; 203:111864. [PMID: 34389351 DOI: 10.1016/j.envres.2021.111864] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/08/2021] [Revised: 06/27/2021] [Accepted: 08/07/2021] [Indexed: 06/13/2023]
Abstract
Epidemiologic studies have shown that the fine particulate matter 2.5 (PM2.5) exaggerates chronic airway inflammation involving in acute exacerbation of chronic obstructive pulmonary disease (AECOPD). Surfactant proteins (SPs) decreases significantly related to airflow limitation and airway inflammation. However, how to restore the reduction of SPs levels in airway inflammation exposed to PM2.5 has not been well understood. In the present study, the SPs including SPA, SPB, SPC and SPD levels in bronchoalveolar lavage fluid (BALF) were detected from patients with stable COPD. Rats were exposed to cigarette smoke and PM2.5. After given with Surfaxin, the expression of SPs, protein kinase C (PKC) and tight junction protein (ZO-1) in lung tissue and the levels of C-reactive protein (CRP) and fibrinogen (FIB) in plasma was observed. The results showed that SPA, SPB and SPD were significantly lower than those of the control group (p < 0.01). PM2.5 aggravated smoking-induced airway inflammation and oxidative stress demonstrated by pathological changes of lung tissue and increased levels of CRP and PKC in vivo. PM2.5 decreased the expression of all the SPs and ZO-1, which could be significantly restored by Surfaxin. These findings indicate that Surfaxin protects the alveolar epithelium from PM2.5 in airway inflammation through increasing SPs.
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Affiliation(s)
- Xian Wen Sun
- Department of Respiratory and Critical Care Medicine, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China; Institute of Respiratory Medicine, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Ying Ni Lin
- Department of Respiratory and Critical Care Medicine, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China; Institute of Respiratory Medicine, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Yong Jie Ding
- Department of Respiratory and Critical Care Medicine, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China; Institute of Respiratory Medicine, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Shi Qi Li
- Department of Respiratory and Critical Care Medicine, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China; Institute of Respiratory Medicine, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Hong Peng Li
- Department of Respiratory and Critical Care Medicine, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China; Institute of Respiratory Medicine, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Jian Ping Zhou
- Department of Respiratory and Critical Care Medicine, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China; Institute of Respiratory Medicine, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Liu Zhang
- Department of Respiratory and Critical Care Medicine, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China; Institute of Respiratory Medicine, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Ji Min Shen
- Department of Respiratory and Critical Care Medicine, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China; Institute of Respiratory Medicine, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Qing Yun Li
- Department of Respiratory and Critical Care Medicine, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China; Institute of Respiratory Medicine, Shanghai Jiao Tong University School of Medicine, Shanghai, China.
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AP-3-dependent targeting of flippase ATP8A1 to lamellar bodies suppresses activation of YAP in alveolar epithelial type 2 cells. Proc Natl Acad Sci U S A 2021; 118:2025208118. [PMID: 33990468 DOI: 10.1073/pnas.2025208118] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
Lamellar bodies (LBs) are lysosome-related organelles (LROs) of surfactant-producing alveolar type 2 (AT2) cells of the distal lung epithelium. Trafficking pathways to LBs have been understudied but are likely critical to AT2 cell homeostasis given associations between genetic defects of endosome to LRO trafficking and pulmonary fibrosis in Hermansky Pudlak syndrome (HPS). Our prior studies uncovered a role for AP-3, defective in HPS type 2, in trafficking Peroxiredoxin-6 to LBs. We now show that the P4-type ATPase ATP8A1 is sorted by AP-3 from early endosomes to LBs through recognition of a C-terminal dileucine-based signal. Disruption of the AP-3/ATP8A1 interaction causes ATP8A1 accumulation in early sorting and/or recycling endosomes, enhancing phosphatidylserine exposure on the cytosolic leaflet. This in turn promotes activation of Yes-activating protein, a transcriptional coactivator, augmenting cell migration and AT2 cell numbers. Together, these studies illuminate a mechanism whereby loss of AP-3-mediated trafficking contributes to a toxic gain-of-function that results in enhanced and sustained activation of a repair pathway associated with pulmonary fibrosis.
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Furse S, Watkins AJ, Koulman A. Extraction of Lipids from Liquid Biological Samples for High-Throughput Lipidomics. Molecules 2020; 25:E3192. [PMID: 32668693 PMCID: PMC7397209 DOI: 10.3390/molecules25143192] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2020] [Revised: 06/26/2020] [Accepted: 07/08/2020] [Indexed: 02/02/2023] Open
Abstract
Extraction of the lipid fraction is a key part of acquiring lipidomics data. High-throughput lipidomics, the extraction of samples in 96w plates that are then run on 96 or 384w plates, has particular requirements that mean special development work is needed to fully optimise an extraction method. Several methods have been published as suitable for it. Here, we test those methods using four liquid matrices: milk, human serum, homogenised mouse liver and homogenised mouse heart. In order to determine the difference in performance of the methods as objectively as possible, we used the number of lipid variables identified, the total signal strength and the coefficient of variance to quantify the performance of the methods. This showed that extraction methods with an aqueous component were generally better than those without for these matrices. However, methods without an aqueous fraction in the extraction were efficient for milk samples. Furthermore, a mixture containing a chlorinated solvent (dichloromethane) appears to be better than an ethereal solvent (tert-butyl methyl ether) for extracting lipids. This study suggests that a 3:1:0.005 mixture of dichloromethane, methanol and triethylammonium chloride, with an aqueous wash, is the most efficient of the currently reported methods for high-throughput lipid extraction and analysis. Further work is required to develop non-aqueous extraction methods that are both convenient and applicable to a broad range of sample types.
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Affiliation(s)
- Samuel Furse
- Core Metabolomics and Lipidomics Laboratory, Wellcome Trust-MRC Institute of Metabolic Science, University of Cambridge, Box 289, Cambridge Biomedical Campus, Hills Road, Cambridge CB2 0QQ, UK
| | - Adam J. Watkins
- Division of Child Health, Obstetrics and Gynaecology, Faculty of Medicine, University of Nottingham, Nottingham NG7 2UH, UK;
| | - Albert Koulman
- Core Metabolomics and Lipidomics Laboratory, Wellcome Trust-MRC Institute of Metabolic Science, University of Cambridge, Box 289, Cambridge Biomedical Campus, Hills Road, Cambridge CB2 0QQ, UK
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Saigusa D, Saito R, Kawamoto K, Uruno A, Kano K, Aoki J, Yamamoto M, Kawamoto T. Conductive Adhesive Film Expands the Utility of Matrix-Assisted Laser Desorption/Ionization Mass Spectrometry Imaging. Anal Chem 2019; 91:8979-8986. [DOI: 10.1021/acs.analchem.9b01159] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Affiliation(s)
- Daisuke Saigusa
- Department of Integrative Genomics, Tohoku Medical Megabank Organization, Tohoku University, 2-1 Seiryo-machi, Aoba-ku, Sendai, Miyagi 980-8573, Japan
- Medical Biochemistry, Tohoku University School of Medicine, 2-1 Seiryo-machi, Aoba-ku, Sendai, Miyagi 980-8575, Japan
- LEAP, Japan Agency for Medical Research and Development (AMED), 1-7-1, Otemachi, Chiyoda-ku, Tokyo, Japan
| | - Ritsumi Saito
- Department of Integrative Genomics, Tohoku Medical Megabank Organization, Tohoku University, 2-1 Seiryo-machi, Aoba-ku, Sendai, Miyagi 980-8573, Japan
- Medical Biochemistry, Tohoku University School of Medicine, 2-1 Seiryo-machi, Aoba-ku, Sendai, Miyagi 980-8575, Japan
| | - Komei Kawamoto
- School of Dental Medicine, Tsurumi University, 2-1-3 Tsurumi,
Tsurumi-ku, Yokohama, Kanagawa 230-8501, Japan
| | - Akira Uruno
- Department of Integrative Genomics, Tohoku Medical Megabank Organization, Tohoku University, 2-1 Seiryo-machi, Aoba-ku, Sendai, Miyagi 980-8573, Japan
- Medical Biochemistry, Tohoku University School of Medicine, 2-1 Seiryo-machi, Aoba-ku, Sendai, Miyagi 980-8575, Japan
| | - Kuniyuki Kano
- Medical Biochemistry, Tohoku University School of Medicine, 2-1 Seiryo-machi, Aoba-ku, Sendai, Miyagi 980-8575, Japan
- Laboratory of Molecular and Cellular Biochemistry, Graduate School of Pharmaceutical Sciences, Tohoku University, 6-3 Aoba, Aramaki-aza,
Aoba-ku, Sendai, Miyagi 980-8578, Japan
| | - Junken Aoki
- Medical Biochemistry, Tohoku University School of Medicine, 2-1 Seiryo-machi, Aoba-ku, Sendai, Miyagi 980-8575, Japan
- Laboratory of Molecular and Cellular Biochemistry, Graduate School of Pharmaceutical Sciences, Tohoku University, 6-3 Aoba, Aramaki-aza,
Aoba-ku, Sendai, Miyagi 980-8578, Japan
| | - Masayuki Yamamoto
- Department of Integrative Genomics, Tohoku Medical Megabank Organization, Tohoku University, 2-1 Seiryo-machi, Aoba-ku, Sendai, Miyagi 980-8573, Japan
- Medical Biochemistry, Tohoku University School of Medicine, 2-1 Seiryo-machi, Aoba-ku, Sendai, Miyagi 980-8575, Japan
| | - Tadafumi Kawamoto
- School of Dental Medicine, Tsurumi University, 2-1-3 Tsurumi,
Tsurumi-ku, Yokohama, Kanagawa 230-8501, Japan
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Christmann U, Hite RD, Witonsky SG, Buechner-Maxwell VA, Wood PL. Evaluation of lipid markers in surfactant obtained from asthmatic horses exposed to hay. Am J Vet Res 2019; 80:300-305. [PMID: 30801214 DOI: 10.2460/ajvr.80.3.300] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
OBJECTIVE To evaluate the lipidomic profile of surfactant obtained from horses with asthma at various clinical stages and to compare results with findings for healthy horses exposed to the same conditions. SAMPLE Surfactant samples obtained from 6 horses with severe asthma and 7 healthy horses. PROCEDURES Clinical evaluation of horses and surfactant analysis were performed. Samples obtained from horses with severe asthma and healthy horses before (baseline), during, and after exposure to hay were analyzed. Crude surfactant pellets were dried prior to dissolution in a solution of isopropanol:methanol:chloroform (4:2:1) containing 7.5mM ammonium acetate. Shotgun lipidomics were performed by use of high-resolution data acquisition on an ion-trap mass spectrometer. Findings were analyzed by use of an ANOVA with a Tukey-Kramer post hoc test. RESULTS Results of lipidomic analysis were evaluated to detect significant differences between groups of horses and among exposure statuses within groups of horses. Significantly increased amounts of cyclic phosphatidic acid (cPA) and diacylglycerol (DAG) were detected in surfactant from severely asthmatic horses during exposure to hay, compared with baseline and postexposure concentrations. Concentrations of cPA and DAG did not change significantly in healthy horses regardless of exposure status. CONCLUSIONS AND CLINICAL RELEVANCE cPA 16:0 and DAG 36:2 were 2 novel lipid mediators identified in surfactant obtained from asthmatic horses with clinical disease. These molecules were likely biomarkers of sustained inflammation. Further studies are needed to evaluate a possible correlation with disease severity and potential alterations in the plasma lipidomic profile of horses with asthma.
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Sluzalska KD, Liebisch G, Ishaque B, Schmitz G, Rickert M, Steinmeyer J. The Effect of Dexamethasone, Adrenergic and Cholinergic Receptor Agonists on Phospholipid Metabolism in Human Osteoarthritic Synoviocytes. Int J Mol Sci 2019; 20:ijms20020342. [PMID: 30650648 PMCID: PMC6359197 DOI: 10.3390/ijms20020342] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2018] [Revised: 01/09/2019] [Accepted: 01/11/2019] [Indexed: 01/07/2023] Open
Abstract
Phospholipids (PLs) possess the unique ability to contribute to synovial joint lubrication. The aim of our study was to determine for the first time the effect of dexamethasone and some adrenergic and cholinergic agonists on the biosynthesis and release of PLs from human fibroblast-like synoviocytes (FLS). Osteoarthritic human knee FLS were treated with dexamethasone, terbutaline, epinephrine, carbachol, and pilocarpine, or the glucocorticoid receptor antagonist RU 486. Simultaneously PL biosynthesis was determined through the incorporation of stable isotope-labeled precursors into PLs. Radioactive isotope-labeled precursors were used to radiolabel PLs for the subsequent quantification of their release into nutrient media. Lipids were extracted and quantified using electrospray ionization tandem mass spectrometry or liquid scintillation counting. Dexamethasone significantly decreased the biosynthesis of phosphatidylcholine, phosphatidylethanolamine (PE), PE-based plasmalogen, and sphingomyelin. The addition of RU 486 abolished these effects. A release of PLs from FLS into nutrient media was not recognized by any of the tested agents. None of the adrenergic or cholinergic receptor agonists modulated the PL biosynthesis. We demonstrate for the first time an inhibitory effect of dexamethasone on the PL biosynthesis of FLS from human knees. Moreover, our study indicates that the PL metabolism of synovial joints and lungs are differently regulated.
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Affiliation(s)
- Katarzyna D Sluzalska
- Laboratory for Experimental Orthopaedics, Department of Orthopaedics, Justus Liebig University Giessen, 35392 Giessen, Germany.
| | - Gerhard Liebisch
- Department of Clinical Chemistry and Laboratory Medicine, University Hospital Regensburg, 93053 Regensburg, Germany.
| | - Bernd Ishaque
- Laboratory for Experimental Orthopaedics, Department of Orthopaedics, Justus Liebig University Giessen, 35392 Giessen, Germany.
| | - Gerd Schmitz
- Department of Clinical Chemistry and Laboratory Medicine, University Hospital Regensburg, 93053 Regensburg, Germany.
| | - Markus Rickert
- Laboratory for Experimental Orthopaedics, Department of Orthopaedics, Justus Liebig University Giessen, 35392 Giessen, Germany.
| | - Juergen Steinmeyer
- Laboratory for Experimental Orthopaedics, Department of Orthopaedics, Justus Liebig University Giessen, 35392 Giessen, Germany.
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Eggers LF, Müller J, Marella C, Scholz V, Watz H, Kugler C, Rabe KF, Goldmann T, Schwudke D. Lipidomes of lung cancer and tumour-free lung tissues reveal distinct molecular signatures for cancer differentiation, age, inflammation, and pulmonary emphysema. Sci Rep 2017; 7:11087. [PMID: 28894173 PMCID: PMC5594029 DOI: 10.1038/s41598-017-11339-1] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2017] [Accepted: 08/23/2017] [Indexed: 01/05/2023] Open
Abstract
Little is known about the human lung lipidome, its variability in different physiological states, its alterations during carcinogenesis and the development of pulmonary emphysema. We investigated how health status might be mirrored in the lung lipidome. Tissues were sampled for both lipidomic and histological analysis. Using a screening approach, we characterised lipidomes of lung cancer tissues and corresponding tumour-free alveolar tissues. We quantified 311 lipids from 11 classes in 43 tissue samples from 26 patients. Tumour tissues exhibited elevated levels of triacylglycerols and cholesteryl esters, as well as a significantly lower abundance of phosphatidylglycerols, which are typical lung surfactant components. Adenocarcinomas and squamous cell carcinomas were distinguished with high specificity based on lipid panels. Lipidomes of tumour biopsy samples showed clear changes depending on their histology and, in particular, their proportion of active tumour cells and stroma. Partial least squares regression showed correlations between lipid profiles of tumour-free alveolar tissues and the degree of emphysema, inflammation status, and the age of patients. Unsaturated long-chain phosphatidylserines and phosphatidylinositols showed a positive correlation with a worsened emphysema status and ageing. This work provides a resource for the human lung lipidome and a systematic data analysis strategy to link clinical characteristics and histology.
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Affiliation(s)
- Lars F Eggers
- Research Center Borstel, Bioanalytical Chemistry, Parkallee 1-40, 23845, Borstel, Germany
| | - Julia Müller
- Pathology of the University Hospital of Lübeck and the Research Center Borstel, Location Borstel, Clinical and Experimental Pathology, 23845, Borstel, Germany
| | - Chakravarthy Marella
- Research Center Borstel, Bioanalytical Chemistry, Parkallee 1-40, 23845, Borstel, Germany
| | - Verena Scholz
- Research Center Borstel, Bioanalytical Chemistry, Parkallee 1-40, 23845, Borstel, Germany
| | - Henrik Watz
- Pulmonary Research Institute at LungenClinic Großhansdorf, Wöhrendamm 80, 22927, Großhansdorf, Germany.,Airway Research Center North, German Center for Lung Research, Wöhrendamm 80, 22927, Großhansdorf, Germany
| | - Christian Kugler
- LungenClinic Großhansdorf, Wöhrendamm 80, 22927, Großhansdorf, Germany
| | - Klaus F Rabe
- Airway Research Center North, German Center for Lung Research, Wöhrendamm 80, 22927, Großhansdorf, Germany.,LungenClinic Großhansdorf, Wöhrendamm 80, 22927, Großhansdorf, Germany
| | - Torsten Goldmann
- Pathology of the University Hospital of Lübeck and the Research Center Borstel, Location Borstel, Clinical and Experimental Pathology, 23845, Borstel, Germany.,Airway Research Center North, German Center for Lung Research, Wöhrendamm 80, 22927, Großhansdorf, Germany
| | - Dominik Schwudke
- Research Center Borstel, Bioanalytical Chemistry, Parkallee 1-40, 23845, Borstel, Germany. .,Airway Research Center North, German Center for Lung Research, Wöhrendamm 80, 22927, Großhansdorf, Germany.
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12
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Beers MF, Moodley Y. When Is an Alveolar Type 2 Cell an Alveolar Type 2 Cell? A Conundrum for Lung Stem Cell Biology and Regenerative Medicine. Am J Respir Cell Mol Biol 2017; 57:18-27. [PMID: 28326803 DOI: 10.1165/rcmb.2016-0426ps] [Citation(s) in RCA: 81] [Impact Index Per Article: 11.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
Generating mature, differentiated, adult lung cells from pluripotent cells, such as induced pluripotent stem cells and embryonic stem cells, offers the hope of both generating disease-specific in vitro models and creating definitive and personalized therapies for a host of debilitating lung parenchymal and airway diseases. With the goal of advancing lung-regenerative medicine, several groups have developed and reported on protocols using defined media, coculture with mesenchymal components, or sequential treatments mimicking lung development, to obtain distal lung epithelial cells from stem cell precursors. However, there remains significant controversy about the degree of differentiation of these cells compared with their primary counterparts, coupled with a lack of consistency or uniformity in assessing the resultant phenotypes. Given the inevitable, exponential expansion of these approaches and the probable, but yet-to-emerge second and higher generation techniques to create such assets, we were prompted to pose the question, what makes a lung epithelial cell a lung epithelial cell? More specifically for this Perspective, we also posed the question, what are the minimum features that constitute an alveolar type (AT) 2 epithelial cell? In addressing this, we summarize a body of work spanning nearly five decades, amassed by a series of "lung epithelial cell biology pioneers," which carefully describes well characterized molecular, functional, and morphological features critical for discriminately assessing an AT2 phenotype. Armed with this, we propose a series of core criteria to assist the field in confirming that cells obtained following a differentiation protocol are indeed mature and functional AT2 epithelial cells.
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Affiliation(s)
- Michael F Beers
- 1 Lung Epithelial Biology Laboratories, Penn Center for Pulmonary Biology, Pulmonary and Critical Care Division, Department of Medicine, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania; and
| | - Yuben Moodley
- 2 University of Western Australia, Harry Perkins Research Institute, Fiona Stanley Hospital, Murdoch, Western Australia, Australia
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13
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Zemski Berry KA, Murphy RC, Kosmider B, Mason RJ. Lipidomic characterization and localization of phospholipids in the human lung. J Lipid Res 2017; 58:926-933. [PMID: 28280112 PMCID: PMC5408611 DOI: 10.1194/jlr.m074955] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2017] [Revised: 02/17/2017] [Indexed: 01/22/2023] Open
Abstract
Lipids play a central role in lung physiology and pathology; however, a comprehensive lipidomic characterization of human pulmonary cells relevant to disease has not been performed. The cells involved in lung host defense, including alveolar macrophages (AMs), bronchial epithelial cells (BECs), and alveolar type II cells (ATIIs), were isolated from human subjects and lipidomic analysis by LC-MS and LC-MS/MS was performed. Additionally, pieces of lung tissue from the same donors were analyzed by MALDI imaging MS in order to determine lipid localization in the tissue. The unique distribution of phospholipids in ATIIs, BECs, and AMs from human subjects was accomplished by subjecting the large number of identified phospholipid molecular species to univariant statistical analysis. Specific MALDI images were generated based on the univariant statistical analysis data to reveal the location of specific cell types within the human lung slice. While the complex composition and function of the lipidome in various disease states is currently poorly understood, this method could be useful for the characterization of lipid alterations in pulmonary disease and may aid in a better understanding of disease pathogenesis.
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Affiliation(s)
| | - Robert C Murphy
- Department of Pharmacology, University of Colorado Denver, Aurora, CO 80045
| | - Beata Kosmider
- Department of Medicine, National Jewish Health, Denver, CO 80206
| | - Robert J Mason
- Department of Medicine, National Jewish Health, Denver, CO 80206
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14
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Brandsma J, Postle AD. Analysis of the regulation of surfactant phosphatidylcholine metabolism using stable isotopes. Ann Anat 2017; 211:176-183. [PMID: 28351529 DOI: 10.1016/j.aanat.2017.02.008] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2016] [Revised: 02/27/2017] [Accepted: 02/28/2017] [Indexed: 01/22/2023]
Abstract
The pathways and mechanisms that regulate pulmonary surfactant synthesis, processing, secretion and catabolism have been extensively characterised using classical biochemical and analytical approaches. These have constructed a model, largely in experimental animals, for surfactant phospholipid metabolism in the alveolar epithelial cell whereby phospholipid synthesised on the endoplasmic reticulum is selectively transported to lamellar body storage vesicles, where it is subsequently processed before secretion into the alveolus. Surfactant phospholipid is a complex mixture of individual molecular species defined by the combination of esterified fatty acid groups and a comprehensive description of surfactant phospholipid metabolism requires consideration of the interactions between such molecular species. However, until recently, lipid analytical techniques have not kept pace with the considerable advances in understanding of the enzymology and molecular biology of surfactant metabolism. Refinements in electrospray ionisation mass spectrometry (ESI-MS) can now provide very sensitive platforms for the rapid characterisation of surfactant phospholipid composition in molecular detail. The combination of ESI-MS and administration of phospholipid substrates labelled with stable isotopes extends this analytical approach to the quantification of synthesis and turnover of individual molecular species of surfactant phospholipid. As this methodology does not involve radioactivity, it is ideally suited to application in clinical studies. This review will provide an overview of the metabolic processes that regulate the molecular specificity of surfactant phosphatidylcholine together with examples of how the application of stable isotope technologies in vivo has, for the first time, begun to explore regulation of the molecular specificity of surfactant synthesis in human subjects.
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Affiliation(s)
- Joost Brandsma
- Academic Unit of Clinical & Experimental Sciences, Faculty of Medicine, University of Southampton, United Kingdom
| | - Anthony D Postle
- Academic Unit of Clinical & Experimental Sciences, Faculty of Medicine, University of Southampton, United Kingdom.
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15
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Bernhard W. Lung surfactant: Function and composition in the context of development and respiratory physiology. Ann Anat 2016; 208:146-150. [DOI: 10.1016/j.aanat.2016.08.003] [Citation(s) in RCA: 47] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2016] [Revised: 08/11/2016] [Accepted: 08/13/2016] [Indexed: 02/07/2023]
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16
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Furse S. Is phosphatidylglycerol essential for terrestrial life? J Chem Biol 2016; 10:1-9. [PMID: 28101250 DOI: 10.1007/s12154-016-0159-3] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2016] [Accepted: 08/29/2016] [Indexed: 01/11/2023] Open
Abstract
Lipids are of increasing importance in understanding biological systems. Lipids carrying an anionic charge are noted in particular for their electrostatic interactions with both proteins and divalent cations. However, the biological, analytical, chemical and biophysical data of such species are rarely considered together, limiting our ability to assess the true role of such lipids in vivo. In this review, evidence from a range of studies about the lipid phosphatidylglycerol is considered. This evidence supports the conclusions that this lipid is ubiquitous in living systems and generally of low abundance but probably fundamental for terrestrial life. Possible reasons for this are discussed and further questions posed.
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Affiliation(s)
- Samuel Furse
- Molekylærbiologisk institutt, Unversitetet i Bergen, Thormøhlens gate 55, 5006 Bergen, Norway
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17
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Griese M, Kirmeier HG, Liebisch G, Rauch D, Stückler F, Schmitz G, Zarbock R. Surfactant lipidomics in healthy children and childhood interstitial lung disease. PLoS One 2015; 10:e0117985. [PMID: 25692779 PMCID: PMC4333572 DOI: 10.1371/journal.pone.0117985] [Citation(s) in RCA: 36] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2014] [Accepted: 01/06/2015] [Indexed: 11/19/2022] Open
Abstract
Background Lipids account for the majority of pulmonary surfactant, which is essential for normal breathing. We asked if interstitial lung diseases (ILD) in children may disrupt alveolar surfactant and give clues for disease categorization. Methods Comprehensive lipidomics profiles of broncho-alveolar lavage fluid were generated in 115 children by electrospray ionization tandem mass spectrometry (ESI-MS/MS). Two reference populations were compared to a broad range of children with ILD. Results Class and species composition in healthy children did not differ from that in children with ILD related to diffuse developmental disorders, chronic tachypnoe of infancy, ILD related to lung vessels and the heart, and ILD related to reactive lymphoid lesions. As groups, ILDs related to the alveolar surfactant region, ILD related to unclear respiratory distress syndrome in the mature neonate, or in part ILD related to growth abnormalities reflecting deficient alveolarisation, had significant alterations of some surfactant specific phospholipids. Additionally, lipids derived from inflammatory processes were identified and differentiated. In children with ABCA3-deficiency from two ILD causing mutations saturated and monounsaturated phosphatidylcholine species with 30 and 32 carbons and almost all phosphatidylglycerol species were severely reduced. In other alveolar disorders lipidomic profiles may be of less diagnostic value, but nevertheless may substantiate lack of significant involvement of mechanisms related to surfactant lipid metabolism. Conclusions Lipidomic profiling may identify specific forms of ILD in children with surfactant alterations and characterized the molecular species pattern likely to be transported by ABCA3 in vivo.
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Affiliation(s)
- Matthias Griese
- Department of Pediatric Pulmonology, Hauner Children’s Hospital, Ludwig Maximilians University, Member of the German Center for Lung Research (DZL), Lindwurmstr. 4a, D-80337 Munich, Germany
- * E-mail:
| | - Hannah G. Kirmeier
- Department of Pediatric Pulmonology, Hauner Children’s Hospital, Ludwig Maximilians University, Member of the German Center for Lung Research (DZL), Lindwurmstr. 4a, D-80337 Munich, Germany
| | - Gerhard Liebisch
- Institute of Computational Biology, Helmholtz Center Munich, Neuherberg, Germany
| | - Daniela Rauch
- Department of Pediatric Pulmonology, Hauner Children’s Hospital, Ludwig Maximilians University, Member of the German Center for Lung Research (DZL), Lindwurmstr. 4a, D-80337 Munich, Germany
| | - Ferdinand Stückler
- Institute of Computational Biology, Helmholtz Center Munich, Neuherberg, Germany
| | - Gerd Schmitz
- Institute of Clinical Chemistry and Laboratory Medicine, University of Regensburg, Franz-Josef-Strauss-Allee 11, 93053 Regensburg, Germany
| | - Ralf Zarbock
- Department of Pediatric Pulmonology, Hauner Children’s Hospital, Ludwig Maximilians University, Member of the German Center for Lung Research (DZL), Lindwurmstr. 4a, D-80337 Munich, Germany
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18
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Aug A, Altraja A, Altraja S, Laaniste L, Mahlapuu R, Soomets U, Kilk K. Alterations of bronchial epithelial metabolome by cigarette smoke are reversible by an antioxidant, O-methyl-L-tyrosinyl-γ-L-glutamyl-L-cysteinylglycine. Am J Respir Cell Mol Biol 2014; 51:586-94. [PMID: 24810251 DOI: 10.1165/rcmb.2013-0377oc] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023] Open
Abstract
Human bronchial epithelial cells (HBECs) have first-line contact with harmful substances during smoking, and changes in their metabolism most likely represent a defining factor in coping with the stress and development of airway diseases. This study was designed to determine the dynamics of metabolome changes in HBECs treated with cigarette smoke condensate (CSC), and to test whether normal metabolism can be restored by synthetic antioxidants. Principal component analysis, based on untargeted mass spectra, indicated that treatment of CSC-exposed HBECs with O-methyl-L-tyrosinyl-γ-L-glutamyl-L-cysteinylglycine (UPF1) acted faster than did N-acetylcysteine to revert the effect of CSC. The maximum effect of 10 μg/ml CSC itself on HBEC cell line, BEAS-2B, metabolism was seen at 2 hours after treatment, with return to the baseline level by 7 hours. In primary HBECs, the initial maximum effect was seen at 1 hour after CSC exposure. Certain metabolites associated with redox pathways and energy production were affected by CSC. Subsequent restoration of their content by UPF1 supports the hypothetical protective capacity of UPF1 against the oxidative stress and increased energy demand, respectively. Furthermore, UPF1 up-regulated the contents of phospholipid species identified as phosphatidylcholines and phosphatidylethanolamines in the CSC-exposed HBECs, indicating possible suppression of inflammatory processes along with an increase in spermidine as an endogenous cytoprotector. In conclusion, with this dynamic metabolomics study, we characterize the durability of the CSC-induced metabolic changes in BEAS-2B line cells and primary HBECs, and demonstrate the ability of UPF1 to significantly accelerate the recovery of HBECs from CSC insult.
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Affiliation(s)
- Argo Aug
- 1 Department of Biochemistry, Institute of Biomedicine and Translational Medicine, University of Tartu, the Centre of Excellence for Translational Medicine, Tartu, Estonia
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Lysophospholipid acyltransferases mediate phosphatidylcholine diversification to achieve the physical properties required in vivo. Cell Metab 2014; 20:295-305. [PMID: 24981836 DOI: 10.1016/j.cmet.2014.05.019] [Citation(s) in RCA: 118] [Impact Index Per Article: 11.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/26/2013] [Revised: 04/18/2014] [Accepted: 05/13/2014] [Indexed: 12/19/2022]
Abstract
The acyl-chain composition of the major mammalian phospholipid phosphatidylcholine (PC) is distinct in various tissues. Although it was classically suggested that PC diversity is acquired through acyl-chain remodeling, the mechanisms and biological relevance of acyl-chain diversity remain unclear. Here, we show that differences in the substrate selectivity of lysophospholipid acyltransferases regulate tissue PC acyl-chain composition through contribution of both the de novo and remodeling pathways, depending on the fatty acid species. Unexpectedly, while dipalmitoyl-PC (DPPC) is enriched through the remodeling pathway, several polyunsaturated PC molecules accumulate during the de novo pathway. We confirmed this concept for DPPC in pulmonary surfactant and showed that the biophysical properties of this lipid are important to prevent the early onset of acute lung injury. We propose a model of harmonized processes for phospholipid diversification to satisfy in vivo requirements, with an example of its biological relevance.
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20
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Nakamura A, Ebina-Shibuya R, Itoh-Nakadai A, Muto A, Shima H, Saigusa D, Aoki J, Ebina M, Nukiwa T, Igarashi K. Transcription repressor Bach2 is required for pulmonary surfactant homeostasis and alveolar macrophage function. ACTA ACUST UNITED AC 2013; 210:2191-204. [PMID: 24127487 PMCID: PMC3804940 DOI: 10.1084/jem.20130028] [Citation(s) in RCA: 82] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
Abstract
Pulmonary alveolar proteinosis (PAP) results from a dysfunction of alveolar macrophages (AMs), chiefly due to disruptions in the signaling of granulocyte macrophage colony-stimulating factor (GM-CSF). We found that mice deficient for the B lymphoid transcription repressor BTB and CNC homology 2 (Bach2) developed PAP-like accumulation of surfactant proteins in the lungs. Bach2 was expressed in AMs, and Bach2-deficient AMs showed alterations in lipid handling in comparison with wild-type (WT) cells. Although Bach2-deficient AMs showed a normal expression of the genes involved in the GM-CSF signaling, they showed an altered expression of the genes involved in chemotaxis, lipid metabolism, and alternative M2 macrophage activation with increased expression of Ym1 and arginase-1, and the M2 regulator Irf4. Peritoneal Bach2-deficient macrophages showed increased Ym1 expression when stimulated with interleukin-4. More eosinophils were present in the lung and peritoneal cavity of Bach2-deficient mice compared with WT mice. The PAP-like lesions in Bach2-deficient mice were relieved by WT bone marrow transplantation even after their development, confirming the hematopoietic origin of the lesions. These results indicate that Bach2 is required for the functional maturation of AMs and pulmonary homeostasis, independently of the GM-CSF signaling.
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Affiliation(s)
- Atsushi Nakamura
- Department of Biochemistry, 2 Division of Respiratory Medicine, and 3 Center for Regulatory Epigenome and Diseases, Tohoku University Graduate School of Medicine, Sendai 980-8575, Japan
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21
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Abstract
The alveolar type II epithelial (ATII) cell is highly specialised for the synthesis and storage, in intracellular lamellar bodies, of phospholipid destined for secretion as pulmonary surfactant into the alveolus. Regulation of the enzymology of surfactant phospholipid synthesis and metabolism has been extensively characterised at both molecular and functional levels, but understanding of surfactant phospholipid metabolism in vivo in either healthy or, especially, diseased lungs is still relatively poorly understood. This review will integrate recent advances in the enzymology of surfactant phospholipid metabolism with metabolic studies in vivo in both experimental animals and human subjects. It will highlight developments in the application of stable isotope-labelled precursor substrates and mass spectrometry to probe lung phospholipid metabolism in terms of individual molecular lipid species and identify areas where a more comprehensive metabolic model would have considerable potential for direct application to disease states.
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22
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Zarbock R, Woischnik M, Sparr C, Thurm T, Kern S, Kaltenborn E, Hector A, Hartl D, Liebisch G, Schmitz G, Griese M. The surfactant protein C mutation A116D alters cellular processing, stress tolerance, surfactant lipid composition, and immune cell activation. BMC Pulm Med 2012; 12:15. [PMID: 22458263 PMCID: PMC3376036 DOI: 10.1186/1471-2466-12-15] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2011] [Accepted: 03/29/2012] [Indexed: 12/26/2022] Open
Abstract
BACKGROUND Surfactant protein C (SP-C) is important for the function of pulmonary surfactant. Heterozygous mutations in SFTPC, the gene encoding SP-C, cause sporadic and familial interstitial lung disease (ILD) in children and adults. Mutations mapping to the BRICHOS domain located within the SP-C proprotein result in perinuclear aggregation of the proprotein. In this study, we investigated the effects of the mutation A116D in the BRICHOS domain of SP-C on cellular homeostasis. We also evaluated the ability of drugs currently used in ILD therapy to counteract these effects. METHODS SP-CA116D was expressed in MLE-12 alveolar epithelial cells. We assessed in vitro the consequences for cellular homeostasis, immune response and effects of azathioprine, hydroxychloroquine, methylprednisolone and cyclophosphamide. RESULTS Stable expression of SP-CA116D in MLE-12 alveolar epithelial cells resulted in increased intracellular accumulation of proSP-C processing intermediates. SP-CA116D expression further led to reduced cell viability and increased levels of the chaperones Hsp90, Hsp70, calreticulin and calnexin. Lipid analysis revealed decreased intracellular levels of phosphatidylcholine (PC) and increased lyso-PC levels. Treatment with methylprednisolone or hydroxychloroquine partially restored these lipid alterations. Furthermore, SP-CA116D cells secreted soluble factors into the medium that modulated surface expression of CCR2 or CXCR1 receptors on CD4+ lymphocytes and neutrophils, suggesting a direct paracrine effect of SP-CA116D on neighboring cells in the alveolar space. CONCLUSIONS We show that the A116D mutation leads to impaired processing of proSP-C in alveolar epithelial cells, alters cell viability and lipid composition, and also activates cells of the immune system. In addition, we show that some of the effects of the mutation on cellular homeostasis can be antagonized by application of pharmaceuticals commonly applied in ILD therapy. Our findings shed new light on the pathomechanisms underlying SP-C deficiency associated ILD and provide insight into the mechanisms by which drugs currently used in ILD therapy act.
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Affiliation(s)
- Ralf Zarbock
- Childrens' Hospital of the Ludwig-Maximilians-University, Lindwurmstr, 4, 80337 Munich, Germany
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23
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Plantier L, Besnard V, Xu Y, Ikegami M, Wert SE, Hunt AN, Postle AD, Whitsett JA. Activation of sterol-response element-binding proteins (SREBP) in alveolar type II cells enhances lipogenesis causing pulmonary lipotoxicity. J Biol Chem 2012; 287:10099-10114. [PMID: 22267724 DOI: 10.1074/jbc.m111.303669] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023] Open
Abstract
Pulmonary inflammation is associated with altered lipid synthesis and clearance related to diabetes, obesity, and various inherited metabolic disorders. In many tissues, lipogenesis is regulated at the transcriptional level by the activity of sterol-response element-binding proteins (SREBP). The role of SREBP activation in the regulation of lipid metabolism in the lung was assessed in mice in which both Insig1 and Insig2 genes, encoding proteins that bind and inhibit SREBPs in the endoplasmic reticulum, were deleted in alveolar type 2 cells. Although deletion of either Insig1 or Insig2 did not alter SREBP activity or lipid homeostasis, deletion of both genes (Insig1/2(Δ/Δ) mice) activated SREBP1, causing marked accumulation of lipids that consisted primarily of cholesterol esters and triglycerides in type 2 epithelial cells and alveolar macrophages. Neutral lipids accumulated in type 2 cells in association with the increase in mRNAs regulating fatty acid, cholesterol synthesis, and inflammation. Although bronchoalveolar lavage fluid phosphatidylcholine was modestly decreased, lung phospholipid content and lung function were maintained. Insig1/2(Δ/Δ) mice developed lung inflammation and airspace abnormalities associated with the accumulation of lipids in alveolar type 2 cells, alveolar macrophages, and within alveolar spaces. Deletion of Insig1/2 activated SREBP-enhancing lipogenesis in respiratory epithelial cells resulting in lipotoxicity-related lung inflammation and tissue remodeling.
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Affiliation(s)
- Laurent Plantier
- Section of Neonatology, Perinatal and Pulmonary Biology, Perinatal Institute, Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio 45229 and
| | - Valérie Besnard
- Section of Neonatology, Perinatal and Pulmonary Biology, Perinatal Institute, Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio 45229 and
| | - Yan Xu
- Section of Neonatology, Perinatal and Pulmonary Biology, Perinatal Institute, Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio 45229 and
| | - Machiko Ikegami
- Section of Neonatology, Perinatal and Pulmonary Biology, Perinatal Institute, Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio 45229 and
| | - Susan E Wert
- Section of Neonatology, Perinatal and Pulmonary Biology, Perinatal Institute, Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio 45229 and
| | - Alan N Hunt
- Division of Clinical and Experimental Sciences, Faculty of Medicine, University of Southampton, Southampton SO16 6YD, United Kingdom
| | - Anthony D Postle
- Division of Clinical and Experimental Sciences, Faculty of Medicine, University of Southampton, Southampton SO16 6YD, United Kingdom
| | - Jeffrey A Whitsett
- Section of Neonatology, Perinatal and Pulmonary Biology, Perinatal Institute, Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio 45229 and.
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24
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Orsi M, Essex JW. The ELBA force field for coarse-grain modeling of lipid membranes. PLoS One 2011; 6:e28637. [PMID: 22194874 PMCID: PMC3241685 DOI: 10.1371/journal.pone.0028637] [Citation(s) in RCA: 131] [Impact Index Per Article: 10.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2011] [Accepted: 11/11/2011] [Indexed: 02/05/2023] Open
Abstract
A new coarse-grain model for molecular dynamics simulation of lipid membranes is presented. Following a simple and conventional approach, lipid molecules are modeled by spherical sites, each representing a group of several atoms. In contrast to common coarse-grain methods, two original (interdependent) features are here adopted. First, the main electrostatics are modeled explicitly by charges and dipoles, which interact realistically through a relative dielectric constant of unity (ε(r) = 1). Second, water molecules are represented individually through a new parametrization of the simple Stockmayer potential for polar fluids; each water molecule is therefore described by a single spherical site embedded with a point dipole. The force field is shown to accurately reproduce the main physical properties of single-species phospholipid bilayers comprising dioleoylphosphatidylcholine (DOPC) and dioleoylphosphatidylethanolamine (DOPE) in the liquid crystal phase, as well as distearoylphosphatidylcholine (DSPC) in the liquid crystal and gel phases. Insights are presented into fundamental properties and phenomena that can be difficult or impossible to study with alternative computational or experimental methods. For example, we investigate the internal pressure distribution, dipole potential, lipid diffusion, and spontaneous self-assembly. Simulations lasting up to 1.5 microseconds were conducted for systems of different sizes (128, 512 and 1058 lipids); this also allowed us to identify size-dependent artifacts that are expected to affect membrane simulations in general. Future extensions and applications are discussed, particularly in relation to the methodology's inherent multiscale capabilities.
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Affiliation(s)
- Mario Orsi
- School of Chemistry, University of Southampton, Southampton, United Kingdom.
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25
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Glasser JR, Mallampalli RK. Surfactant and its role in the pathobiology of pulmonary infection. Microbes Infect 2011; 14:17-25. [PMID: 21945366 DOI: 10.1016/j.micinf.2011.08.019] [Citation(s) in RCA: 55] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2011] [Revised: 08/06/2011] [Accepted: 08/09/2011] [Indexed: 12/19/2022]
Abstract
Pulmonary surfactant is a complex surface-active substance comprised of key phospholipids and proteins that has many essential functions. Surfactant's unique composition is integrally related to its surface-active properties, its critical role in host defense, and emerging immunomodulatory activities ascribed to surfactant lipids. Together these effector functions provide for lung stability and protection from a barrage of potentially virulent infectious pathogens.
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Affiliation(s)
- Jennifer R Glasser
- Department of Medicine, Acute Lung Injury Center of Excellence, Pittsburgh, PA 15213, USA
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26
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Postle AD, Henderson NG, Koster G, Clark HW, Hunt AN. Analysis of lung surfactant phosphatidylcholine metabolism in transgenic mice using stable isotopes. Chem Phys Lipids 2011; 164:549-55. [DOI: 10.1016/j.chemphyslip.2011.04.004] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2011] [Revised: 04/09/2011] [Accepted: 04/10/2011] [Indexed: 11/26/2022]
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27
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Berry KAZ, Li B, Reynolds SD, Barkley RM, Gijón MA, Hankin JA, Henson PM, Murphy RC. MALDI imaging MS of phospholipids in the mouse lung. J Lipid Res 2011; 52:1551-60. [PMID: 21508254 DOI: 10.1194/jlr.m015750] [Citation(s) in RCA: 77] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023] Open
Abstract
Lipid mediators are important in lung biochemistry and are derived from the enzymatic oxidation of arachidonic and docosahexaenoic acids, which are PUFAs that are present in phospholipids in cell membranes. In this study, MALDI imaging MS was used to determine the localization of arachidonate- and docosahexaenoate-containing phospholipids in mouse lung. These PUFA-containing phospholipids were determined to be uniquely abundant at the lining of small and large airways, which were unequivocally identified by immunohistochemistry. In addition, it was found that the blood vessels present in the lung were characterized by sphingomyelin molecular species, and lung surfactant phospholipids appeared evenly distributed throughout the lung parenchyma, indicating alveolar localization. This technique revealed unexpected high concentrations of arachidonate- and docosahexaenoate-containing phospholipids lining the airways in pulmonary tissue, which could serve as precursors of lipid mediators affecting airways biology.
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Affiliation(s)
- Karin A Zemski Berry
- Department of Pharmacology, University of Colorado Denver, 12801 East 17 Avenue, Mail Stop 8303, Aurora, CO 80045, USA.
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Debouzy JC, Crouzier D, Favier AL, Perino J. ESR and NMR studies provide evidence that phosphatidyl glycerol specifically interacts with poxvirus membranes. Virol J 2010; 7:379. [PMID: 21194478 PMCID: PMC3023795 DOI: 10.1186/1743-422x-7-379] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2010] [Accepted: 12/31/2010] [Indexed: 11/21/2022] Open
Abstract
Background The lung would be the first organ targeted in case of the use of Variola virus (the causative agent of smallpox) as a bioweapon. Pulmonary surfactant composed of lipids (90%) and proteins (10%) is considered the major physiological barrier against airborne pathogens. The principle phospholipid components of lung surfactant were examined in an in vitro model to characterize their interactions with VACV, a surrogate for variola virus. One of them, Dipalmitoyl phosphatidylglycerol (DPPG), was recently shown to inhibit VACV cell infection. Results The interactions of poxvirus particles from the Western Reserve strain (VACV-WR) and the Lister strain (VACV-List) with model membranes for pulmonary surfactant phospholipids, in particular DPPG, were studied by Electron Spin Resonance (ESR) and proton Nuclear Magnetic Resonance (1H-NMR). ESR experiments showed that DPPG exhibits specific interactions with both viruses, while NMR experiments allowed us to deduce its stoichiometry and to propose a model for the mechanism of interaction at the molecular level. Conclusions These results confirm the ability of DPPG to strongly bind to VACV and suggest that similar interactions occur with variola virus. Similar studies of the interactions between lipids and other airborne pathogens are warranted.
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Affiliation(s)
- Jean-Claude Debouzy
- Unité de biophysique cellulaire et moléculaire, CRSSA-IRBA, 24 avenue des maquis du Grésivaudan, 38702 La Tronche cedex, France
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Perino J, Crouzier D, Spehner D, Debouzy JC, Garin D, Crance JM, Favier AL. Lung surfactant DPPG phospholipid inhibits vaccinia virus infection. Antiviral Res 2010; 89:89-97. [PMID: 21095206 DOI: 10.1016/j.antiviral.2010.11.009] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2010] [Revised: 11/03/2010] [Accepted: 11/14/2010] [Indexed: 10/18/2022]
Abstract
Vaccinia virus (VACV) was used as a surrogate of Variola virus (genus Orthopoxvirus), the causative agent of smallpox, to study orthopoxvirus infection via the respiratory airway. Lung surfactant, a physiological barrier to infection encountered by the virus, is predominantly composed of phospholipids whose role during orthopoxvirus infection has not been investigated. An attenuated Lister strain, derived from the traditional smallpox vaccine and the Western Reserve (WR) strain, lethal for mice infected by the respiratory route, were examined for their ability to bind various surfactant phospholipids. Dipalmitoyl phosphatidylglycerol (DPPG) was found to interact with both VACV strains. DPPG incorporated in small unilamellar vesicle (SUV-DPPG) inhibited VACV cell infection, unlike other phospholipids tested. Both pre-incubation of virus with SUV-DPPG and pretreatment of the cell with SUV-DPPG inhibited cell infection. This specific DPPG effect was shown to be concentration and time dependent and to prevent the first step of the viral cycle, i.e. virus cell attachment. Cryo-electron microscopy highlighted the interaction between the virus and SUV-DPPG. In the presence of the phospholipid, virus particles displayed a hedgehog-like appearance due to the attachment of lipid vesicles. Mice infected intranasally with VACV-WR pre-incubated with SUV-DPPG survived a lethal infection. These data suggest that DPPG in lung surfactant could reduce the amount of orthopoxvirus particles able to infect pneumocytes at the beginning of a respiratory poxvirus infection. The knowledge acquired during this study of virus-DPPG interactions may be used to develop novel chemotherapeutic strategies for smallpox.
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Affiliation(s)
- Julien Perino
- Laboratoire de Virologie, Institut de Recherche Biomédicale des Armées-Antenne du Centre de Recherches du Service de Santé des Armées, 38702 La Tronche Cedex, France
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Woischnik M, Sparr C, Kern S, Thurm T, Hector A, Hartl D, Liebisch G, Mulugeta S, Beers MF, Schmitz G, Griese M. A non-BRICHOS surfactant protein c mutation disrupts epithelial cell function and intercellular signaling. BMC Cell Biol 2010; 11:88. [PMID: 21092132 PMCID: PMC2994813 DOI: 10.1186/1471-2121-11-88] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2010] [Accepted: 11/20/2010] [Indexed: 12/18/2022] Open
Abstract
Background Heterozygous mutations of SFTPC, the gene encoding surfactant protein C (SP-C), cause sporadic and familial interstitial lung disease (ILD) in children and adults. The most frequent SFTPC mutation in ILD patients leads to a threonine for isoleucine substitution at position 73 (I73T) of the SP-C preprotein (proSP-C), however little is known about the cellular consequences of SP-CI73T expression. Results To address this, we stably expressed SP-CI73T in cultured MLE-12 alveolar epithelial cells. This resulted in increased intracellular accumulation of proSP-C processing intermediates, which matched proSP-C species recovered in bronchial lavage fluid from patients with this mutation. Exposure of SP-CI73T cells to drugs currently used empirically in ILD therapy, cyclophosphamide, azathioprine, hydroxychloroquine or methylprednisolone, enhanced expression of the chaperones HSP90, HSP70, calreticulin and calnexin. SP-CI73T mutants had decreased intracellular phosphatidylcholine level (PC) and increased lyso-PC level without appreciable changes of other phospholipids. Treatment with methylprednisolone or hydroxychloroquine partially restored these lipid alterations. Furthermore, SP-CI73T cells secreted into the medium soluble factors that modulated surface expression of CCR2 or CXCR1 receptors on CD4+ lymphocytes and neutrophils, suggesting a direct paracrine influence of SP-CI73T on neighboring cells in the alveolar space. Conclusion We show that I73T mutation leads to impaired processing of proSP-C in alveolar type II cells, alters their stress tolerance and surfactant lipid composition, and activates cells of the immune system. In addition, we show that some of the mentioned cellular aspects behind the disease can be modulated by application of pharmaceutical drugs commonly applied in the ILD therapy.
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Affiliation(s)
- Markus Woischnik
- Department of Pneumology, Dr von Hauner Children's Hospital, Ludwig-Maximilians University, Lindwurmstr 4, Munich 80337, Germany
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Pynn CJ, Picardi MV, Nicholson T, Wistuba D, Poets CF, Schleicher E, Perez-Gil J, Bernhard W. Myristate is selectively incorporated into surfactant and decreases dipalmitoylphosphatidylcholine without functional impairment. Am J Physiol Regul Integr Comp Physiol 2010; 299:R1306-16. [DOI: 10.1152/ajpregu.00380.2010] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Lung surfactant mainly comprises phosphatidylcholines (PC), together with phosphatidylglycerols and surfactant proteins SP-A to SP-D. Dipalmitoyl-PC (PC16:0/16:0), palmitoylmyristoyl-PC (PC16:0/14:0), and palmitoylpalmitoleoyl-PC (PC16:0/16:1) together comprise 75–80% of surfactant PC. During alveolarization, which occurs postnatally in the rat, PC16:0/14:0 reversibly increases at the expense of PC16:0/16:0. As lipoproteins modify surfactant metabolism, we postulated an extrapulmonary origin of PC16:0/14:0 enrichment in surfactant. We, therefore, fed rats (d19–26) with trilaurin (C12:03), trimyristin (C14:03), tripalmitin (C16:03), triolein (C18:13) or trilinolein (C18:23) vs. carbohydrate diet to assess their effects on surfactant PC composition and surface tension function using a captive bubble surfactometer. Metabolism was assessed with deuterated C12:0 (ω-d3-C12:0) and ω-d3-C14:0. C14:03 increased PC16:0/14:0 in surfactant from 12 ± 1 to 45 ± 3% and decreased PC16:0/16:0 from 47 ± 1 to 29 ± 2%, with no impairment of surface tension function. Combined phospholipase A2 assay and mass spectrometry revealed that 50% of the PC16:0/14:0 peak comprised its isomer 1-myristoyl-2-palmitoyl-PC (PC14:0/16:0). While C12:03 was excluded from incorporation into PC, it increased PC16:0/14:0 as well. C16:03, C18:13, and C18:23 had no significant effect on PC16:0/16:0 or PC16:0/14:0. d3-C14:0 was enriched in lung PC, either via direct supply or via d3-C12:0 elongation. Enrichment of d3-C14:0 in surfactant PC contrasted its rapid turnover in plasma and liver PC, where its elongation product d3-C16:0 surmounted d3-C14:0. In summary, high surfactant PC16:0/14:0 during lung development correlates with C14:0 and C12:0 supply via specific C14:0 enrichment into lung PC. Surfactant that is high in PC16:0/14:0 but low in PC16:0/16:0 is compatible with normal respiration and surfactant function in vitro.
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Affiliation(s)
- Christopher J. Pynn
- Departments of 1Neonatology and
- Internal Medicine IV, Faculty of Medicine, and
| | - M. Victoria Picardi
- Department of Bioquimica y Biologia Molecular, Universidad Complutense, Madrid, Spain
| | - Tim Nicholson
- Department of Chemistry, Eberhard-Karls-University, Tübingen, Germany; and
| | - Dorothee Wistuba
- Department of Chemistry, Eberhard-Karls-University, Tübingen, Germany; and
| | | | | | - Jesus Perez-Gil
- Department of Bioquimica y Biologia Molecular, Universidad Complutense, Madrid, Spain
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Ballard PL, Lee JW, Fang X, Chapin C, Allen L, Segal MR, Fischer H, Illek B, Gonzales LW, Kolla V, Matthay MA. Regulated gene expression in cultured type II cells of adult human lung. Am J Physiol Lung Cell Mol Physiol 2010; 299:L36-50. [PMID: 20382749 DOI: 10.1152/ajplung.00427.2009] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
Alveolar type II cells have multiple functions, including surfactant production and fluid clearance, which are critical for lung function. Differentiation of type II cells occurs in cultured fetal lung epithelial cells treated with dexamethasone plus cAMP and isobutylmethylxanthine (DCI) and involves increased expression of 388 genes. In this study, type II cells of human adult lung were isolated at approximately 95% purity, and gene expression was determined (Affymetrix) before and after culturing 5 days on collagen-coated dishes with or without DCI for the final 3 days. In freshly isolated cells, highly expressed genes included SFTPA/B/C, SCGB1A, IL8, CXCL2, and SFN in addition to ubiquitously expressed genes. Transcript abundance was correlated between fetal and adult cells (r = 0.88), with a subset of 187 genes primarily related to inflammation and immunity that were expressed >10-fold higher in adult cells. During control culture, expression increased for 8.1% of expressed genes and decreased for approximately 4% including 118 immune response and 10 surfactant-related genes. DCI treatment promoted lamellar body production and increased expression of approximately 3% of probed genes by > or =1.5-fold; 40% of these were also induced in fetal cells. Highly induced genes (> or =10-fold) included PGC, ZBTB16, DUOX1, PLUNC, CIT, and CRTAC1. Twenty-five induced genes, including six genes related to surfactant (SFTPA/B/C, PGC, CEBPD, and ADFP), also had decreased expression during control culture and thus are candidates for hormonal regulation in vivo. Our results further define the adult human type II cell molecular phenotype and demonstrate that a subset of genes remains hormone responsive in cultured adult cells.
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Affiliation(s)
- Philip L Ballard
- Department of Pediatrics, University of California San Francisco, San Francisco, USA.
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Besnard V, Matsuzaki Y, Clark J, Xu Y, Wert SE, Ikegami M, Stahlman MT, Weaver TE, Hunt AN, Postle AD, Whitsett JA. Conditional deletion of Abca3 in alveolar type II cells alters surfactant homeostasis in newborn and adult mice. Am J Physiol Lung Cell Mol Physiol 2010; 298:L646-59. [PMID: 20190032 DOI: 10.1152/ajplung.00409.2009] [Citation(s) in RCA: 46] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
ATP-binding cassette A3 (ABCA3) is a lipid transport protein required for synthesis and storage of pulmonary surfactant in type II cells in the alveoli. Abca3 was conditionally deleted in respiratory epithelial cells (Abca3(Δ/Δ)) in vivo. The majority of mice in which Abca3 was deleted in alveolar type II cells died shortly after birth from respiratory distress related to surfactant deficiency. Approximately 30% of the Abca3(Δ/Δ) mice survived after birth. Surviving Abca3(Δ/Δ) mice developed emphysema in the absence of significant pulmonary inflammation. Staining of lung tissue and mRNA isolated from alveolar type II cells demonstrated that ∼50% of alveolar type II cells lacked ABCA3. Phospholipid content and composition were altered in lung tissue, lamellar bodies, and bronchoalveolar lavage fluid from adult Abca3(Δ/Δ) mice. In adult Abca3(Δ/Δ) mice, cells lacking ABCA3 had decreased expression of mRNAs associated with lipid synthesis and transport. FOXA2 and CCAAT enhancer-binding protein-α, transcription factors known to regulate genes regulating lung lipid metabolism, were markedly decreased in cells lacking ABCA3. Deletion of Abca3 disrupted surfactant lipid synthesis in a cell-autonomous manner. Compensatory surfactant synthesis was initiated in ABCA3-sufficient type II cells, indicating that surfactant homeostasis is a highly regulated process that includes sensing and coregulation among alveolar type II cells.
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Affiliation(s)
- Valérie Besnard
- The Perinatal Institute and Section of Neonatology, Perinatal and Pulmonary Biology, Cincinnati Children’s Hospital Medical Center, Department of Pediatrics and University of Cincinnati College of Medicine, Ohio
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Bernhard W, Pynn CJ. Therapeutic lung surfactants as carriers for other therapeutics--a matter of vision, courage and determination. Pediatr Pulmonol 2009; 44:1157-8. [PMID: 19911361 DOI: 10.1002/ppul.21123] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Affiliation(s)
- Wolfgang Bernhard
- Department of Neonatology, Faculty of Medicine, Eberhard-Karls-University, Calwer Strasse 7 & Otfried-Müller-Str. 27, D-72076 Tübingen, Germany.
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35
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Masukawa Y, Narita H, Sato H, Naoe A, Kondo N, Sugai Y, Oba T, Homma R, Ishikawa J, Takagi Y, Kitahara T. Comprehensive quantification of ceramide species in human stratum corneum. J Lipid Res 2009; 50:1708-19. [PMID: 19349641 DOI: 10.1194/jlr.d800055-jlr200] [Citation(s) in RCA: 150] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023] Open
Abstract
One of the key challenges in lipidomics is to quantify lipidomes of interest, as it is practically impossible to collect all authentic materials covering the targeted lipidomes. For diverse ceramides (CER) in human stratum corneum (SC) that play important physicochemical roles in the skin, we developed a novel method for quantification of the overall CER species by improving our previously reported profiling technique using normal-phase liquid chromatography-electrospray ionization-mass spectrometry (NPLC-ESI-MS). The use of simultaneous selected ion monitoring measurement of as many as 182 kinds of molecular-related ions enables the highly sensitive detection of the overall CER species, as they can be analyzed in only one SC-stripped tape as small as 5 mm x 10 mm. To comprehensively quantify CERs, including those not available as authentic species, we designed a procedure to estimate their levels using relative responses of representative authentic species covering the species targeted, considering the systematic error based on intra-/inter-day analyses. The CER levels obtained by this method were comparable to those determined by conventional thin-layer chromatography (TLC), which guarantees the validity of this method. This method opens lipidomics approaches for CERs in the SC.
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Affiliation(s)
- Yoshinori Masukawa
- Tochigi Research Laboratories, Kao Corporation, Ichikai, Haga, Tochigi 321-3497, Japan.
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36
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Besnard V, Wert SE, Stahlman MT, Postle AD, Xu Y, Ikegami M, Whitsett JA. Deletion of Scap in alveolar type II cells influences lung lipid homeostasis and identifies a compensatory role for pulmonary lipofibroblasts. J Biol Chem 2009; 284:4018-30. [PMID: 19074148 PMCID: PMC2635058 DOI: 10.1074/jbc.m805388200] [Citation(s) in RCA: 58] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2008] [Revised: 11/21/2008] [Indexed: 12/22/2022] Open
Abstract
Pulmonary function after birth is dependent upon surfactant lipids that reduce surface tension in the alveoli. The sterol-responsive element-binding proteins (SREBPs) are transcription factors regulating expression of genes controlling lipid homeostasis in many tissues. To identify the role of SREBPs in the lung, we conditionally deleted the SREBP cleavage-activating protein gene, Scap, in respiratory epithelial cells (ScapDelta/Delta) in vivo. Prior to birth (E18.5), deletion of Scap decreased the expression of both SREBPs and a number of genes regulating fatty acid and cholesterol metabolism. Nevertheless, ScapDelta/Delta mice survived postnatally, surfactant and lung tissue lipids being substantially normalized in adult ScapDelta/Delta mice. Although phospholipid synthesis was decreased in type II cells from adult ScapDelta/Delta mice, lipid storage, synthesis, and transfer by lung lipofibroblasts were increased. mRNA microarray data indicated that SCAP influenced two major gene networks, one regulating lipid metabolism and the other stress-related responses. Deletion of the SCAP/SREBP pathway in respiratory epithelial cells altered lung lipid homeostasis and induced compensatory lipid accumulation and synthesis in lung lipofibroblasts.
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Affiliation(s)
- Valérie Besnard
- Division of Pulmonary Biology, Cincinnati Children's Hospital Medical Center, Department of Pediatrics, the University of Cincinnati College of Medicine, Cincinnati, Ohio 45229-3039, USA
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38
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Swain RJ, Kemp SJ, Goldstraw P, Tetley TD, Stevens MM. Spectral monitoring of surfactant clearance during alveolar epithelial type II cell differentiation. Biophys J 2008; 95:5978-87. [PMID: 18820234 PMCID: PMC2599825 DOI: 10.1529/biophysj.108.136168] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2008] [Accepted: 08/25/2008] [Indexed: 11/18/2022] Open
Abstract
In this study, we report on the noninvasive identification of spectral markers of alveolar type II (ATII) cell differentiation in vitro using Raman microspectroscopy. ATII cells are progenitor cells for alveolar type I (ATI) cells in vivo, and spontaneously differentiate toward an ATI-like phenotype in culture. We analyzed undifferentiated and differentiated primary human ATII cells, and correlated Raman spectral changes to cellular changes in morphology and marker protein synthesis (surfactant protein C, alkaline phosphatase, caveolin-1). Undifferentiated ATII cells demonstrated spectra with strong phospholipid vibrations, arising from alveolar surfactant stored within cytoplasmic lamellar bodies (Lbs). Differentiated ATI-like cells yielded spectra with significantly less lipid content. Factor analysis revealed a phospholipid-dominated spectral component as the main discriminator between the ATII and ATI-like phenotypes. Spectral modeling of the data revealed a significant decrease in the spectral contribution of cellular lipids-specifically phosphatidyl choline, the main constituent of surfactant, as ATII cells differentiate. These observations were consistent with the clearance of surfactant from Lbs as ATII cells differentiate, and were further supported by cytochemical staining for Lbs. These results demonstrate the first spectral characterization of primary human ATII cells, and provide insight into the biochemical properties of alveolar surfactant in its unperturbed cellular environment.
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Affiliation(s)
- Robin J Swain
- Department of Materials and Institute of Biomedical Engineering, Imperial College London, London, United Kingdom
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39
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A matter of fat: An introduction to lipidomic profiling methods. J Chromatogr B Analyt Technol Biomed Life Sci 2008; 871:174-81. [DOI: 10.1016/j.jchromb.2008.04.002] [Citation(s) in RCA: 106] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2008] [Revised: 03/27/2008] [Accepted: 04/03/2008] [Indexed: 02/02/2023]
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40
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Louhelainen N, Myllärniemi M, Rahman I, Kinnula VL. Airway biomarkers of the oxidant burden in asthma and chronic obstructive pulmonary disease: current and future perspectives. Int J Chron Obstruct Pulmon Dis 2008; 3:585-603. [PMID: 19281076 PMCID: PMC2650600 DOI: 10.2147/copd.s3671] [Citation(s) in RCA: 48] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
Abstract
The pathogenesis of asthma and chronic obstructive pulmonary disease (COPD) has been claimed to be attributable to increased systemic and local oxidative stress. Detection of the oxidant burden and evaluation of their progression and phenotypes by oxidant biomarkers have proved challenging and difficult. A large number of asthmatics are cigarette smokers and smoke itself contains oxidants complicating further the use of oxidant biomarkers. One of the most widely used oxidant markers in asthma is exhaled nitric oxide (NO), which plays an important role in the pathogenesis of asthma and disease monitoring. Another oxidant marker that has been widely investigated in COPD is 8-isoprostane, but it is probably not capable of differentiating asthma from COPD, or even sensitive in the early assessment of these diseases. None of the current biomarkers have been shown to be better than exhaled NO in asthma. There is a need to identify new biomarkers for obstructive airway diseases, especially their differential diagnosis. A comprehensive evaluation of oxidant markers and their combinations will be presented in this review. In brief, it seems that additional analyses utilizing powerful tools such as genomics, metabolomics, lipidomics, and proteomics will be required to improve the specificity and sensitivity of the next generation of biomarkers.
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Affiliation(s)
- Noora Louhelainen
- Department of Medicine, Division of Pulmonary Medicine, University of Helsinki and Helsinki University Central Hospital, Helsinki, Finland
| | - Marjukka Myllärniemi
- Department of Medicine, Division of Pulmonary Medicine, University of Helsinki and Helsinki University Central Hospital, Helsinki, Finland
| | - Irfan Rahman
- Department of Environmental Medicine and the Lung Biology and Disease Program, University of Rochester Medical Center, Rochester, New York, USA
| | - Vuokko L Kinnula
- Department of Medicine, Division of Pulmonary Medicine, University of Helsinki and Helsinki University Central Hospital, Helsinki, Finland
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41
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Bernhard W, Schmiedl A, Koster G, Orgeig S, Acevedo C, Poets CF, Postle AD. Developmental changes in rat surfactant lipidomics in the context of species variability. Pediatr Pulmonol 2007; 42:794-804. [PMID: 17659602 DOI: 10.1002/ppul.20657] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Lung surfactant comprises mainly phosphatidylcholine (PC) species together with phosphatidylglycerols and surfactant proteins (SP) SP-A to -D. Changes in the concentrations of its principal components dipalmitoyl-PC, palmitoylmyristoyl-PC, palmitoylpalmitoleoyl-PC relative to developmental, structural and physiological differences are only partially understood. Particularly, their attribution to differences in air-liquid interface curvature, compared with dynamic parameters, such as respiratory rate, are controversial. We postulated that during alveolarization the changes in these principal PC components of surfactant differ from those in other phospholipid parameters, and that across endothermic vertebrates their concentrations are related to lung physiology rather than structure. We therefore investigated in rats from postnatal day (d)1 to d42 the pattern of surfactant phospholipids relative to alveolarization (d4-d14), and we discuss these changes in terms of molecular adaptation to pulmonary structure or physiology. Contrary to mammals with advanced alveolarization and increased respiratory rate (RR) at term, concentrations of dipalmitoyl-PC (49-52%) and palmitoylmyristoyl-PC (7-9%) in lung lavage fluid were identical at d1 and d42. At d7-d14, when in rats RR is increased, palmitoyl-myristoyl-PC transiently increased by 2.5- to 3.9-fold at the expense of dipalmitoyl-PC (-32% to 34%) and palmitoyl-palmitoleoyl-PC (-16%). Other lipidomic changes followed essentially different patterns of increase or decrease. Palmitoyl-myristoyl-PC was increased in large aggregates suggesting that it is an integral component of active surfactant. In the overall context of vertebrates, irrespective of age and lung structure, fractions of palmitoyl-myristoyl-PC, dipalmitoyl-PC and palmitoyl-palmitoleoyl-PC correlate with differences in RR rather than alveolar curvature. In adult mammals, however, only concentrations of palmitoyl-palmitoleoyl-PC correlate with RR.
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Affiliation(s)
- Wolfgang Bernhard
- Department of Neonatology, Faculty of Medicine, Eberhard-Karls-University, Tübingen, Germany.
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42
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Andreeva AV, Kutuzov MA, Voyno-Yasenetskaya TA. Regulation of surfactant secretion in alveolar type II cells. Am J Physiol Lung Cell Mol Physiol 2007; 293:L259-71. [PMID: 17496061 DOI: 10.1152/ajplung.00112.2007] [Citation(s) in RCA: 147] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Molecular mechanisms of surfactant delivery to the air/liquid interface in the lung, which is crucial to lower the surface tension, have been studied for more than two decades. Lung surfactant is synthesized in the alveolar type II cells. Its delivery to the cell surface is preceded by surfactant component synthesis, packaging into specialized organelles termed lamellar bodies, delivery to the apical plasma membrane and fusion. Secreted surfactant undergoes reuptake, intracellular processing, and finally resecretion of recycled material. This review focuses on the mechanisms of delivery of surfactant components to and their secretion from lamellar bodies. Lamellar bodies-independent secretion is also considered. Signal transduction pathways involved in regulation of these processes are discussed as well as disorders associated with their malfunction.
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Affiliation(s)
- Alexandra V Andreeva
- Department of Pharmacology, University of Illinois College of Medicine, Center for Lung and Vascular Biology, Chicago, IL, USA
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43
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Postle AD, Wilton DC, Hunt AN, Attard GS. Probing phospholipid dynamics by electrospray ionisation mass spectrometry. Prog Lipid Res 2007; 46:200-24. [PMID: 17540449 DOI: 10.1016/j.plipres.2007.04.001] [Citation(s) in RCA: 82] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2007] [Revised: 03/30/2007] [Accepted: 04/04/2007] [Indexed: 11/25/2022]
Abstract
Recent advances in electrospray ionisation mass spectrometry (ESI-MS) have greatly facilitated the analysis of phospholipid molecular species in a growing diversity of biological and clinical settings. The combination of ESI-MS and metabolic labelling employing substrates labelled with stable isotopes is especially exciting, permitting studies of phospholipid synthesis and turnover in vivo. This review will first describe the methodology involved and will then detail dynamic lipidomic studies that have applied the stable isotope incorporation approach. Finally, it will summarise the increasing number of studies that have used ESI-MS to characterise structural and signalling phospholipid molecular species in development and disease.
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Affiliation(s)
- Anthony D Postle
- School of Medicine, University of Southampton, Southampton SO17 1BJ, UK.
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Fischer H, Gonzales LK, Kolla V, Schwarzer C, Miot F, Illek B, Ballard PL. Developmental regulation of DUOX1 expression and function in human fetal lung epithelial cells. Am J Physiol Lung Cell Mol Physiol 2007; 292:L1506-14. [PMID: 17337509 DOI: 10.1152/ajplung.00029.2007] [Citation(s) in RCA: 54] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
The purpose of this study was to determine the expression and cellular functions of the epithelial NADPH oxidase DUOX1 during alveolar type II cell development. When human fetal lung cells (gestational age 11-22 wk) were cultured to confluency on permeable filters, exposure of cells to a hormone mixture (dexamethasone, 8-Br-cAMP, and IBMX, together referred to as DCI) resulted in differentiation of cells into a mature type II phenotype as assessed by expression of lamellar bodies, surfactant proteins, and transepithelial electrical parameters. After 6 days in culture in presence of DCI, transepithelial resistance (2,616 +/- 529 Omega.cm(2)) and potential (-8.5 +/- 0.6 mV) indicated epithelial polarization. At the same time, treatment with DCI significantly increased the mRNA expression of DUOX1 ( approximately 21-fold), its maturation factor DUOXA1 ( approximately 12-fold), as well as DUOX protein ( approximately 12-fold), which was localized near the apical cell pole in confluent cultures. For comparison, in fetal lung specimens, DUOX protein was not detectable at up to 27 wk of gestational age but was strongly upregulated after 32 wk. Function of DUOX1 was assessed by measuring H(2)O(2) and acid production. Rates of H(2)O(2) production were increased by DCI treatment and blocked by small interfering RNA directed against DUOX1 or by diphenylene iodonium. DCI-treated cultures also showed increased intracellular acid production and acid release into the mucosal medium, and acid production was largely blocked by knockdown of DUOX1 mRNA. These data establish the regulated expression of DUOX1 during alveolar maturation, and indicate DUOX1 in alveolar H(2)O(2) and acid secretion by differentiated type II cells.
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Affiliation(s)
- Horst Fischer
- Children's Hospital Oakland Research Institute, 5700 Martin Luther King Jr. Way, Oakland, CA 94609-1673, USA.
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Kolla V, Gonzales LW, Gonzales J, Wang P, Angampalli S, Feinstein SI, Ballard PL. Thyroid transcription factor in differentiating type II cells: regulation, isoforms, and target genes. Am J Respir Cell Mol Biol 2007; 36:213-25. [PMID: 16960125 PMCID: PMC1899316 DOI: 10.1165/rcmb.2006-0207oc] [Citation(s) in RCA: 60] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2006] [Accepted: 08/18/2006] [Indexed: 11/24/2022] Open
Abstract
Thyroid transcription factor-1 (TTF-1, product of the Nkx2.1 gene) is essential for branching morphogenesis of the lung and enhances expression of surfactant proteins by alveolar type II cells. We investigated expression of two TTF-1 mRNA transcripts, generated by alternative start sites and coding for 42- and 46-kD protein isoforms in the mouse, during hormone-induced differentiation of human fetal lung type II cells in culture. Transcript for 42-kD TTF-1 was 20-fold more abundant than TTF-1(46) mRNA by RT-PCR. Only 42-kD protein was detected in lung cells, and its content increased during in vivo development and in response to in vitro glucocorticoid plus cAMP treatment. To examine TTF-1 target proteins, recombinant, phosphorylated TTF-1(42) was expressed in nuclei of cells by adenovirus transduction. By microarray analysis, 14 genes were comparably induced by recombinant TTF-1 (rTTF-1) and hormone treatment, and 9 additional hormone-responsive genes, including surfactant proteins-A/B/C, were partially induced by rTTF-1. The most highly (approximately 10-fold) TTF-1-induced genes were DC-LAMP (LAMP3) and CEACAM6 with induction confirmed by Western analysis and immunostaining. Treatment of cells with hormones plus small inhibitory RNA directed toward TTF-1 reduced TTF-1 content by approximately 50% and inhibited hormone induction of the 23 genes induced by rTTF-1. In addition, knockdown of TTF-1 inhibited 72 of 274 other genes induced by hormones. We conclude that 42-kD TTF-1 is required for induction of a subset of regulated genes during type II cell differentiation.
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Affiliation(s)
- Venkatadri Kolla
- Department of Pediatrics, Children's Hospital of Philadelphia, University of Pennsylvania School of Medicine, USA
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