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Liu JY, George IC, Hussain S, Sayes CM. High-throughput screening of respiratory hazards: Exploring lung surfactant inhibition with 20 benchmark chemicals. Toxicology 2024; 504:153785. [PMID: 38518839 DOI: 10.1016/j.tox.2024.153785] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2024] [Revised: 03/05/2024] [Accepted: 03/19/2024] [Indexed: 03/24/2024]
Abstract
As environmental air quality worsens and respiratory health injuries and diseases increase, it is essential to enhance our ability to develop better methods to identify potential hazards. One promising approach in emerging toxicology involves the utilization of lung surfactant as a model that addresses the limitations of conventional in vitro toxicology methods by incorporating the biophysical aspect of inhalation. This study employed a constrained drop surfactometer to assess 20 chemicals for potential surfactant inhibition. Of these, eight were identified as inhibiting lung surfactant function: 1-aminoethanol, bovine serum albumin, maleic anhydride, propylene glycol, sodium glycocholate, sodium taurocholate, sodium taurodeoxycholate, and Triton X-100. These results are consistent with previously reported chemical-induced acute lung dysfunction in vivo. The study provides information on each chemical's minimum and maximum surface tension conditions and corresponding relative area and contact angle values. Isotherms and box plots are reported for selected chemicals across doses, and vector plots are used to summarize and compare the results concisely. This lung surfactant bioassay is a promising non-animal model for hazard identification, with broader implications for developing predictive modeling and decision-making tools.
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Affiliation(s)
- James Y Liu
- Department of Environmental Science, Baylor University, Waco, TX 76798-7266, USA
| | - Ian C George
- 711th Human Performance Wing, Air Force Research Laboratory, Dayton, OH, USA
| | - Saber Hussain
- 711th Human Performance Wing, Air Force Research Laboratory, Dayton, OH, USA
| | - Christie M Sayes
- Department of Environmental Science, Baylor University, Waco, TX 76798-7266, USA.
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2
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Xu W, Ma X, Wang Q, Ye J, Wang N, Ye Z, Chen T. GCN5L1 regulates pulmonary surfactant production by modulating lamellar body biogenesis and trafficking in mouse alveolar epithelial cells. Cell Mol Biol Lett 2023; 28:90. [PMID: 37936104 PMCID: PMC10631113 DOI: 10.1186/s11658-023-00506-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2023] [Accepted: 10/25/2023] [Indexed: 11/09/2023] Open
Abstract
BACKGROUND The pulmonary surfactant that lines the air-liquid surface within alveoli is a protein-lipid mixture essential for gas exchange. Surfactant lipids and proteins are synthesized and stored in the lamellar body (LB) before being secreted from alveolar type II (AT2) cells. The molecular and cellular mechanisms that regulate these processes are incompletely understood. We previously identified an essential role of general control of amino acid synthesis 5 like 1 (GCN5L1) and the biogenesis of lysosome-related organelle complex 1 subunit 1 (BLOS1) in surfactant system development in zebrafish. Here, we explored the role of GCN5L1 in pulmonary surfactant regulation. METHOD GCN5L1 knockout cell lines were generated with the CRISPR/Cas9 system. Cell viability was analyzed by MTT assay. Released surfactant proteins were measured by ELISA. Released surfactant lipids were measured based on coupled enzymatic reactions. Gene overexpression was mediated through lentivirus. The RNA levels were detected through RNA-sequencing (RNA-seq) and quantitative reverse transcription (qRT)- polymerase chain reaction (PCR). The protein levels were detected through western blotting. The cellular localization was analyzed by immunofluorescence. Morphology of the lamellar body was analyzed through transmission electron microscopy (TEM), Lysotracker staining, and BODIPY phosphatidylcholine labeling. RESULTS Knocking out GCN5L1 in MLE-12 significantly decreased the release of surfactant proteins and lipids. We detected the downregulation of some surfactant-related genes and misregulation of the ROS-Erk-Foxo1-Cebpα axis in mutant cells. Modulating the activity of the axis or reconstructing the mitochondrial expression of GCN5L1 could partially restore the expression of these surfactant-related genes. We further showed that MLE-12 cells contained many LB-like organelles that were lipid enriched and positive for multiple LB markers. These organelles were smaller in size and accumulated in the absence of GCN5L1, indicating both biogenesis and trafficking defects. Accumulated endogenous surfactant protein (SP)-B or exogenously expressed SP-B/SP-C in adenosine triphosphate-binding cassette transporterA3 (ABCA3)-positive organelles was detected in mutant cells. GCN5L1 localized to the mitochondria and LBs. Reconstruction of mitochondrial GCN5L1 expression rescued the organelle morphology but failed to restore the trafficking defect and surfactant release, indicating specific roles associated with different subcellular localizations. CONCLUSIONS In summary, our study identified GCN5L1 as a new regulator of pulmonary surfactant that plays a role in the biogenesis and positioning/trafficking of surfactant-containing LBs.
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Affiliation(s)
- Wenqin Xu
- Central Laboratory, Yijishan Hospital of Wannan Medical College, Wuhu, China
- Anhui Province Key Laboratory of Non-Coding RNA Basic and Clinical Transformation, Wannan Medical College, Wuhu, China
- Clinical Research Center for Critical Respiratory Medicine of Anhui Province, Wannan Medical College, Wuhu, China
| | - Xiaocui Ma
- Henan Clinical Research Center of Childhood Diseases, Children's Hospital Affiliated to Zhengzhou University, Zhengzhou, China
| | - Qing Wang
- Central Laboratory, Yijishan Hospital of Wannan Medical College, Wuhu, China
- Anhui Province Key Laboratory of Non-Coding RNA Basic and Clinical Transformation, Wannan Medical College, Wuhu, China
- Clinical Research Center for Critical Respiratory Medicine of Anhui Province, Wannan Medical College, Wuhu, China
| | - Jingjing Ye
- Central Laboratory, Yijishan Hospital of Wannan Medical College, Wuhu, China
- Anhui Province Key Laboratory of Non-Coding RNA Basic and Clinical Transformation, Wannan Medical College, Wuhu, China
- Clinical Research Center for Critical Respiratory Medicine of Anhui Province, Wannan Medical College, Wuhu, China
| | - Nengqian Wang
- Department of Pediatrics, Yijishan Hospital of Wannan Medical College, Wuhu, China
| | - Zhenzhen Ye
- Department of Pediatrics, Yijishan Hospital of Wannan Medical College, Wuhu, China
| | - Tianbing Chen
- Central Laboratory, Yijishan Hospital of Wannan Medical College, Wuhu, China.
- Anhui Province Key Laboratory of Non-Coding RNA Basic and Clinical Transformation, Wannan Medical College, Wuhu, China.
- Clinical Research Center for Critical Respiratory Medicine of Anhui Province, Wannan Medical College, Wuhu, China.
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3
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Stevenson ER, Smith LC, Wilkinson ML, Lee SJ, Gow AJ. Etiology of lipid-laden macrophages in the lung. Int Immunopharmacol 2023; 123:110719. [PMID: 37595492 PMCID: PMC10734282 DOI: 10.1016/j.intimp.2023.110719] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2023] [Revised: 07/18/2023] [Accepted: 07/25/2023] [Indexed: 08/20/2023]
Abstract
Uniquely positioned as sentinel cells constantly exposed to the environment, pulmonary macrophages are vital for the maintenance of the lung lining. These cells are responsible for the clearance of xenobiotics, pathogen detection and clearance, and homeostatic functions such as surfactant recycling. Among the spectrum of phenotypes that may be expressed by macrophages in the lung, the pulmonary lipid-laden phenotype is less commonly studied in comparison to its circulatory counterpart, the atherosclerotic lesion-associated foam cell, or the acutely activated inflammatory macrophage. Herein, we propose that lipid-laden macrophage formation in the lung is governed by lipid acquisition, storage, metabolism, and export processes. The cellular balance of these four processes is critical to the maintenance of homeostasis and the prevention of aberrant signaling that may contribute to lung pathologies. This review aims to examine mechanisms and signaling pathways that are involved in lipid-laden macrophage formation and the potential consequences of this phenotype in the lung.
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Affiliation(s)
- E R Stevenson
- Department of Pharmacology and Toxicology, Ernest Mario School of Pharmacy, Rutgers University, Piscataway, NJ, United States
| | - L C Smith
- Department of Pharmacology and Toxicology, Ernest Mario School of Pharmacy, Rutgers University, Piscataway, NJ, United States; Department of Pharmaceutical Sciences, University of Connecticut School of Pharmacy, Storrs, CT, United States
| | - M L Wilkinson
- Department of Pharmacology and Toxicology, Ernest Mario School of Pharmacy, Rutgers University, Piscataway, NJ, United States
| | - S J Lee
- Department of Pharmacology and Toxicology, Ernest Mario School of Pharmacy, Rutgers University, Piscataway, NJ, United States
| | - A J Gow
- Department of Pharmacology and Toxicology, Ernest Mario School of Pharmacy, Rutgers University, Piscataway, NJ, United States
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4
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Fang Z, Chen H. The in vivo drug delivery pattern of the organelle-targeting small molecules. Adv Drug Deliv Rev 2023; 200:115020. [PMID: 37481114 DOI: 10.1016/j.addr.2023.115020] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2023] [Revised: 07/07/2023] [Accepted: 07/16/2023] [Indexed: 07/24/2023]
Abstract
Eukaryotic cell organelles sustain the life of cells. Their structural changes and dysfunctions can cause abnormal physiological activities and lead to various diseases. Molecular imaging technology enables the visualization of subcellular structures, cells, organs, and the whole living body's structure and metabolism dynamic changes. This could help to reveal the pharmacology mechanisms and drug delivery pathway in vivo. This article discusses the relationship between organelles and human disease, reviews recent probes targeting organelles and their behavior in vivo. We found that mitochondria-targeting probes prefer accumulation in the intestine, heart, and tumor. The lysosome-targeting probe accumulates in the intestine and tumor. Few studies on endoplasmic reticulum- or Golgi apparatus-targeting probes have been reported for in vivo imaging. We hope this review could provide new insights for developing and applying organelle-targeting probes.
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Affiliation(s)
- Zhao Fang
- Molecular Imaging Center, State Key Laboratory of Chemical Biology, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai 201203, China
| | - Hao Chen
- Molecular Imaging Center, State Key Laboratory of Chemical Biology, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai 201203, China.
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5
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Xu C, Xu J, Tang HW, Ericsson M, Weng JH, DiRusso J, Hu Y, Ma W, Asara JM, Perrimon N. A phosphate-sensing organelle regulates phosphate and tissue homeostasis. Nature 2023; 617:798-806. [PMID: 37138087 PMCID: PMC10443203 DOI: 10.1038/s41586-023-06039-y] [Citation(s) in RCA: 12] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2020] [Accepted: 03/31/2023] [Indexed: 05/05/2023]
Abstract
Inorganic phosphate (Pi) is one of the essential molecules for life. However, little is known about intracellular Pi metabolism and signalling in animal tissues1. Following the observation that chronic Pi starvation causes hyperproliferation in the digestive epithelium of Drosophila melanogaster, we determined that Pi starvation triggers the downregulation of the Pi transporter PXo. In line with Pi starvation, PXo deficiency caused midgut hyperproliferation. Interestingly, immunostaining and ultrastructural analyses showed that PXo specifically marks non-canonical multilamellar organelles (PXo bodies). Further, by Pi imaging with a Förster resonance energy transfer (FRET)-based Pi sensor2, we found that PXo restricts cytosolic Pi levels. PXo bodies require PXo for biogenesis and undergo degradation following Pi starvation. Proteomic and lipidomic characterization of PXo bodies unveiled their distinct feature as an intracellular Pi reserve. Therefore, Pi starvation triggers PXo downregulation and PXo body degradation as a compensatory mechanism to increase cytosolic Pi. Finally, we identified connector of kinase to AP-1 (Cka), a component of the STRIPAK complex and JNK signalling3, as the mediator of PXo knockdown- or Pi starvation-induced hyperproliferation. Altogether, our study uncovers PXo bodies as a critical regulator of cytosolic Pi levels and identifies a Pi-dependent PXo-Cka-JNK signalling cascade controlling tissue homeostasis.
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Affiliation(s)
- Chiwei Xu
- Department of Genetics, Blavatnik Institute, Harvard Medical School, Boston, MA, USA.
- Robin Chemers Neustein Laboratory of Mammalian Development and Cell Biology, The Rockefeller University, New York, NY, USA.
| | - Jun Xu
- Department of Genetics, Blavatnik Institute, Harvard Medical School, Boston, MA, USA
- CAS Key Laboratory of Insect Developmental and Evolutionary Biology, CAS Center for Excellence in Molecular Plant Sciences, Chinese Academy of Sciences, Shanghai, China
| | - Hong-Wen Tang
- Department of Genetics, Blavatnik Institute, Harvard Medical School, Boston, MA, USA
- Program in Cancer and Stem Cell Biology, Duke-NUS Medical School, Singapore, Singapore
| | - Maria Ericsson
- Department of Cell Biology, Electron Microscopy Facility, Blavatnik Institute, Harvard Medical School, Boston, MA, USA
| | - Jui-Hsia Weng
- Institute of Biological Chemistry, Academia Sinica, Taipei, Taiwan
| | - Jonathan DiRusso
- Department of Genetics, Blavatnik Institute, Harvard Medical School, Boston, MA, USA
| | - Yanhui Hu
- Department of Genetics, Blavatnik Institute, Harvard Medical School, Boston, MA, USA
| | - Wenzhe Ma
- Department of Systems Biology, Harvard Medical School, Boston, MA, USA
| | - John M Asara
- Department of Medicine, Blavatnik Institute, Harvard Medical School, Boston, MA, USA
- Department of Signal Transduction, Beth Israel Deaconess Medical Center, Boston, MA, USA
| | - Norbert Perrimon
- Department of Genetics, Blavatnik Institute, Harvard Medical School, Boston, MA, USA.
- Howard Hughes Medical Institute, Harvard Medical School, Boston, MA, USA.
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Nakamura Y, Aizawa C, Kawata H, Nakanishi T. N-glycosylation modifies prostaglandin E 2 uptake by reducing cell surface expression of SLCO2A1. Prostaglandins Other Lipid Mediat 2023; 165:106714. [PMID: 36706979 DOI: 10.1016/j.prostaglandins.2023.106714] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2022] [Revised: 01/10/2023] [Accepted: 01/23/2023] [Indexed: 01/26/2023]
Abstract
SLCO2A1 functions as a prostaglandin (PG) influx transporter to facilitate intracellular oxidation of PGs and its defect causes dysregulation of PG signaling and metabolism. This study aimed to clarify effects of N-glycosylation on functional SLCO2A1 expression. Putative N-glycosylation site(s) (N134, N478, and/or N491) of human SLCO2A1 were mutated to Q and wild-type (WT) and mutant forms were expressed in HEK293 and human epithelial cells. Molecular weight of WT decreased to nearly 55 kDa by PNGase F treatment and was identical to that of triple mutant (TM, i.e., N134Q/N478Q/N491Q). Transport affinity of TM for PGE2 (Km of 392.7 nM) was comparable to that of WT (Km of 328.5 nM); however, immunoassays showed that TM cell surface expression remained at 24% of WT in HEK293 cells, resulting in a reduced cellular PGE2 uptake. These results suggest N-glycosylation modifies cellular PGE2 uptake by decreasing SLCO2A1 localization to the plasma membrane.
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Affiliation(s)
- Yoshinobu Nakamura
- Laboratory of Membrane Transport for Biopharmaceutics, Faculty of Pharmacy, Takasaki University of Health and Welfare, Takasaki, Japan
| | - Chisato Aizawa
- Laboratory of Membrane Transport for Biopharmaceutics, Faculty of Pharmacy, Takasaki University of Health and Welfare, Takasaki, Japan
| | - Hinako Kawata
- Laboratory of Membrane Transport for Biopharmaceutics, Faculty of Pharmacy, Takasaki University of Health and Welfare, Takasaki, Japan
| | - Takeo Nakanishi
- Laboratory of Membrane Transport for Biopharmaceutics, Faculty of Pharmacy, Takasaki University of Health and Welfare, Takasaki, Japan.
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A dominant negative variant of RAB5B disrupts maturation of surfactant protein B and surfactant protein C. Proc Natl Acad Sci U S A 2022; 119:2105228119. [PMID: 35121658 PMCID: PMC8832968 DOI: 10.1073/pnas.2105228119] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 12/21/2021] [Indexed: 12/19/2022] Open
Abstract
The Rab5 GTPase functions in early endosome (EE) fusion in the endocytic pathway. Here, we propose that RAB5B also has a noncanonical vesicular fusion function in the regulated secretion pathway that produces mature surfactant proteins SP-B and SP-C in the lung. This function was revealed from investigation of a proband with interstitial lung disease suggestive of a surfactant dysfunction disorder who carried a de novo Asp136His variant in the RAB5B gene. Our modeling in C. elegans provided information on the genetic and cell biological mechanism, and analyses of proband and normal lung biopsies suggested a function for RAB5B and EEs in surfactant protein processing/trafficking. This work indicates that RAB5B p.Asp136His causes a surfactant dysfunction disorder. Pathogenic variants in surfactant proteins SP-B and SP-C cause surfactant deficiency and interstitial lung disease. Surfactant proteins are synthesized as precursors (proSP-B, proSP-C), trafficked, and processed via a vesicular-regulated secretion pathway; however, control of vesicular trafficking events is not fully understood. Through the Undiagnosed Diseases Network, we evaluated a child with interstitial lung disease suggestive of surfactant deficiency. Variants in known surfactant dysfunction disorder genes were not found in trio exome sequencing. Instead, a de novo heterozygous variant in RAB5B was identified in the Ras/Rab GTPases family nucleotide binding domain, p.Asp136His. Functional studies were performed in Caenorhabditis elegans by knocking the proband variant into the conserved position (Asp135) of the ortholog, rab-5. Genetic analysis demonstrated that rab-5[Asp135His] is damaging, producing a strong dominant negative gene product. rab-5[Asp135His] heterozygotes were also defective in endocytosis and early endosome (EE) fusion. Immunostaining studies of the proband’s lung biopsy revealed that RAB5B and EE marker EEA1 were significantly reduced in alveolar type II cells and that mature SP-B and SP-C were significantly reduced, while proSP-B and proSP-C were normal. Furthermore, staining normal lung showed colocalization of RAB5B and EEA1 with proSP-B and proSP-C. These findings indicate that dominant negative–acting RAB5B Asp136His and EE dysfunction cause a defect in processing/trafficking to produce mature SP-B and SP-C, resulting in interstitial lung disease, and that RAB5B and EEs normally function in the surfactant secretion pathway. Together, the data suggest a noncanonical function for RAB5B and identify RAB5B p.Asp136His as a genetic mechanism for a surfactant dysfunction disorder.
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8
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Dietl P, Frick M. Channels and Transporters of the Pulmonary Lamellar Body in Health and Disease. Cells 2021; 11:45. [PMID: 35011607 PMCID: PMC8750383 DOI: 10.3390/cells11010045] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2021] [Revised: 12/20/2021] [Accepted: 12/22/2021] [Indexed: 02/06/2023] Open
Abstract
The lamellar body (LB) of the alveolar type II (ATII) cell is a lysosome-related organelle (LRO) that contains surfactant, a complex mix of mainly lipids and specific surfactant proteins. The major function of surfactant in the lung is the reduction of surface tension and stabilization of alveoli during respiration. Its lack or deficiency may cause various forms of respiratory distress syndrome (RDS). Surfactant is also part of the innate immune system in the lung, defending the organism against air-borne pathogens. The limiting (organelle) membrane that encloses the LB contains various transporters that are in part responsible for translocating lipids and other organic material into the LB. On the other hand, this membrane contains ion transporters and channels that maintain a specific internal ion composition including the acidic pH of about 5. Furthermore, P2X4 receptors, ligand gated ion channels of the danger signal ATP, are expressed in the limiting LB membrane. They play a role in boosting surfactant secretion and fluid clearance. In this review, we discuss the functions of these transporting pathways of the LB, including possible roles in disease and as therapeutic targets, including viral infections such as SARS-CoV-2.
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Affiliation(s)
- Paul Dietl
- Institute of General Physiology, Ulm University, Albert-Einstein-Allee 11, 89081 Ulm, Germany
| | - Manfred Frick
- Institute of General Physiology, Ulm University, Albert-Einstein-Allee 11, 89081 Ulm, Germany
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9
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Mahanty S, Setty SRG. Epidermal Lamellar Body Biogenesis: Insight Into the Roles of Golgi and Lysosomes. Front Cell Dev Biol 2021; 9:701950. [PMID: 34458262 PMCID: PMC8387949 DOI: 10.3389/fcell.2021.701950] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2021] [Accepted: 07/09/2021] [Indexed: 12/25/2022] Open
Abstract
Epidermal lamellar bodies (eLBs) are secretory organelles that carry a wide variety of secretory cargo required for skin homeostasis. eLBs belong to the class of lysosome-related organelles (LROs), which are cell-type-specific organelles that perform diverse functions. The formation of eLBs is thought to be related to that of other LROs, which are formed either through the gradual maturation of Golgi/endosomal precursors or by the conversion of conventional lysosomes. Current evidence suggests that eLB biogenesis presumably initiate from trans-Golgi network and receive cargo from endosomes, and also acquire lysosome characteristics during maturation. These multistep biogenesis processes are frequently disrupted in human skin disorders. However, many gaps remain in our understanding of eLB biogenesis and their relationship to skin diseases. Here, we describe our current understanding on eLB biogenesis with a focus on cargo transport to this LRO and highlight key areas where future research is needed.
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Affiliation(s)
- Sarmistha Mahanty
- Department of Microbiology and Cell Biology, Indian Institute of Science, Bengaluru, India
| | - Subba Rao Gangi Setty
- Department of Microbiology and Cell Biology, Indian Institute of Science, Bengaluru, India
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10
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Araki M, Ito K, Takatori S, Ito G, Tomita T. BORCS6 is involved in the enlargement of lung lamellar bodies in Lrrk2 knockout mice. Hum Mol Genet 2021; 30:1618-1631. [PMID: 34077533 DOI: 10.1093/hmg/ddab146] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2021] [Revised: 05/24/2021] [Accepted: 05/25/2021] [Indexed: 12/12/2022] Open
Abstract
Leucine-rich repeat kinase 2 (LRRK2) has been implicated in the pathogenesis of Parkinson disease. It has been shown that Lrrk2 knockout (KO) rodents have enlarged lamellar bodies (LBs) in their alveolar epithelial type II cells, although the underlying mechanisms remain unclear. Here we performed proteomic analyses on LBs isolated from Lrrk2 KO mice and found that the LB proteome is substantially different in Lrrk2 KO mice compared with wild-type mice. In Lrrk2 KO LBs, several Rab proteins were increased, and subunit proteins of BLOC-1-related complex (BORC) were decreased. The amount of surfactant protein C was significantly decreased in the bronchoalveolar lavage fluid obtained from Lrrk2 KO mice, suggesting that LB exocytosis is impaired in Lrrk2 KO mice. We also found that the enlargement of LBs is recapitulated in A549 cells upon KO of LRRK2 or by treating cells with LRRK2 inhibitors. Using this model, we show that KO of BORCS6, a BORC subunit gene, but not other BORC genes, causes LB enlargement. Our findings implicate the LRRK2-BORCS6 pathway in the maintenance of LB morphology.
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Affiliation(s)
- Miho Araki
- Laboratory of Neuropathology and Neuroscience, Graduate School of Pharmaceutical Sciences, The University of Tokyo, Tokyo 113-0033, Japan
| | - Kyohei Ito
- Laboratory of Neuropathology and Neuroscience, Graduate School of Pharmaceutical Sciences, The University of Tokyo, Tokyo 113-0033, Japan
| | - Sho Takatori
- Laboratory of Neuropathology and Neuroscience, Graduate School of Pharmaceutical Sciences, The University of Tokyo, Tokyo 113-0033, Japan
| | - Genta Ito
- Social Cooperation Program of Brain and Neurological Disorders, Graduate School of Pharmaceutical Sciences, The University of Tokyo, Tokyo 113-0033, Japan
| | - Taisuke Tomita
- Laboratory of Neuropathology and Neuroscience, Graduate School of Pharmaceutical Sciences, The University of Tokyo, Tokyo 113-0033, Japan
- Social Cooperation Program of Brain and Neurological Disorders, Graduate School of Pharmaceutical Sciences, The University of Tokyo, Tokyo 113-0033, Japan
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11
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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: 15] [Impact Index Per Article: 5.0] [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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12
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García‐Sanz P, M.F.G. Aerts J, Moratalla R. The Role of Cholesterol in α-Synuclein and Lewy Body Pathology in GBA1 Parkinson's Disease. Mov Disord 2021; 36:1070-1085. [PMID: 33219714 PMCID: PMC8247417 DOI: 10.1002/mds.28396] [Citation(s) in RCA: 54] [Impact Index Per Article: 18.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2020] [Revised: 11/01/2020] [Accepted: 11/03/2020] [Indexed: 02/06/2023] Open
Abstract
Parkinson's disease (PD) is a progressive neurodegenerative disease where dopaminergic neurons in the substantia nigra are lost, resulting in a decrease in striatal dopamine and, consequently, motor control. Dopaminergic degeneration is associated with the appearance of Lewy bodies, which contain membrane structures and proteins, including α-synuclein (α-Syn), in surviving neurons. PD displays a multifactorial pathology and develops from interactions between multiple elements, such as age, environmental conditions, and genetics. Mutations in the GBA1 gene represent one of the major genetic risk factors for PD. This gene encodes an essential lysosomal enzyme called β-glucocerebrosidase (GCase), which is responsible for degrading the glycolipid glucocerebroside into glucose and ceramide. GCase can generate glucosylated cholesterol via transglucosylation and can also degrade the sterol glucoside. Although the molecular mechanisms that predispose an individual to neurodegeneration remain unknown, the role of cholesterol in PD pathology deserves consideration. Disturbed cellular cholesterol metabolism, as reflected by accumulation of lysosomal cholesterol in GBA1-associated PD cellular models, could contribute to changes in lipid rafts, which are necessary for synaptic localization and vesicle cycling and modulation of synaptic integrity. α-Syn has been implicated in the regulation of neuronal cholesterol, and cholesterol facilitates interactions between α-Syn oligomers. In this review, we integrate the results of previous studies and describe the cholesterol landscape in cellular homeostasis and neuronal function. We discuss its implication in α-Syn and Lewy body pathophysiological mechanisms underlying PD, focusing on the role of GCase and cholesterol. © 2020 The Authors. Movement Disorders published by Wiley Periodicals LLC on behalf of International Parkinson and Movement Disorder Society.
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Affiliation(s)
- Patricia García‐Sanz
- Instituto Cajal, CSICMadridSpain
- Centro de Investigación Biomédica en Red sobre Enfermedades NeurodegenerativasInstituto de Salud Carlos IIIMadridSpain
| | - Johannes M.F.G. Aerts
- Medical Biochemistry, Leiden Institute of Chemistry, Leiden UniversityFaculty of ScienceLeidenthe Netherlands
| | - Rosario Moratalla
- Instituto Cajal, CSICMadridSpain
- Centro de Investigación Biomédica en Red sobre Enfermedades NeurodegenerativasInstituto de Salud Carlos IIIMadridSpain
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13
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Sever N, Miličić G, Bodnar NO, Wu X, Rapoport TA. Mechanism of Lamellar Body Formation by Lung Surfactant Protein B. Mol Cell 2020; 81:49-66.e8. [PMID: 33242393 DOI: 10.1016/j.molcel.2020.10.042] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2020] [Revised: 09/14/2020] [Accepted: 10/28/2020] [Indexed: 11/30/2022]
Abstract
Breathing depends on pulmonary surfactant, a mixture of phospholipids and proteins, secreted by alveolar type II cells. Surfactant requires lamellar bodies (LBs), organelles containing densely packed concentric membrane layers, for storage and secretion. LB biogenesis remains mysterious but requires surfactant protein B (SP-B), which is synthesized as a precursor (pre-proSP-B) that is cleaved during trafficking into three related proteins. Here, we elucidate the functions and cooperation of these proteins in LB formation. We show that the N-terminal domain of proSP-B is a phospholipid-binding and -transfer protein whose activities are required for proSP-B export from the endoplasmic reticulum (ER) and sorting to LBs, the conversion of proSP-B into lipoprotein particles, and neonatal viability in mice. The C-terminal domain facilitates ER export of proSP-B. The mature middle domain, generated after proteolytic cleavage of proSP-B, generates the striking membrane layers characteristic of LBs. Together, our results lead to a mechanistic model of LB biogenesis.
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Affiliation(s)
- Navdar Sever
- Howard Hughes Medical Institute and Department of Cell Biology, Harvard Medical School, 240 Longwood Avenue, Boston, MA 02115, USA
| | - Goran Miličić
- Howard Hughes Medical Institute and Department of Cell Biology, Harvard Medical School, 240 Longwood Avenue, Boston, MA 02115, USA
| | - Nicholas O Bodnar
- Howard Hughes Medical Institute and Department of Cell Biology, Harvard Medical School, 240 Longwood Avenue, Boston, MA 02115, USA
| | - Xudong Wu
- Howard Hughes Medical Institute and Department of Cell Biology, Harvard Medical School, 240 Longwood Avenue, Boston, MA 02115, USA
| | - Tom A Rapoport
- Howard Hughes Medical Institute and Department of Cell Biology, Harvard Medical School, 240 Longwood Avenue, Boston, MA 02115, USA.
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14
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Katsumiti A, Ruenraroengsak P, Cajaraville MP, Thorley AJ, Tetley TD. Immortalisation of primary human alveolar epithelial lung cells using a non-viral vector to study respiratory bioreactivity in vitro. Sci Rep 2020; 10:20486. [PMID: 33235275 PMCID: PMC7686381 DOI: 10.1038/s41598-020-77191-y] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2020] [Accepted: 10/27/2020] [Indexed: 01/06/2023] Open
Abstract
To overcome the scarcity of primary human alveolar epithelial cells for lung research, and the limitations of current cell lines to recapitulate the phenotype, functional and molecular characteristics of the healthy human alveolar epithelium, we have developed a new method to immortalise primary human alveolar epithelial lung cells using a non-viral vector to transfect the telomerase catalytic subunit (hTERT) and the simian virus 40 large-tumour antigen (SV40). Twelve strains of immortalised cells (ICs) were generated and characterised using molecular, immunochemical and morphological techniques. Cell proliferation and sensitivity to polystyrene nanoparticles (PS) were evaluated. ICs expressed caveolin-1, podoplanin and receptor for advanced glycation end-products (RAGE), and most cells were negative for alkaline phosphatase staining, indicating characteristics of AT1-like cells. However, most strains also contained some cells that expressed pro-surfactant protein C, classically described to be expressed only by AT2 cells. Thus, the ICs mimic the cellular heterogeneity in the human alveolar epithelium. These ICs can be passaged, replicate rapidly and remain confluent beyond 15 days. ICs showed differential sensitivity to positive and negatively charged PS nanoparticles, illustrating their potential value as an in vitro model to study respiratory bioreactivity. These novel ICs offer a unique resource to study human alveolar epithelial biology.
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Affiliation(s)
- Alberto Katsumiti
- CBET Research Group, Department of Zoology and Animal Cell Biology, Faculty of Science and Technology and Research Centre for Experimental Marine Biology and Biotechnology PiE, University of the Basque Country UPV/EHU, Plentzia, Basque Country, Spain. .,National Heart and Lung Institute, Imperial College London, London, SW7 2AZ, UK.
| | - Pakatip Ruenraroengsak
- Department of Materials and London Centre for Nanotechnology, Imperial College London, London, SW7 2AZ, UK.,Department of Pharmacy, Faculty of Pharmacy, Mahidol University, 447 Sri-Ayuthaya Road, Rajathevi, Bangkok, 10400, Thailand
| | - Miren P Cajaraville
- CBET Research Group, Department of Zoology and Animal Cell Biology, Faculty of Science and Technology and Research Centre for Experimental Marine Biology and Biotechnology PiE, University of the Basque Country UPV/EHU, Plentzia, Basque Country, Spain
| | - Andrew J Thorley
- National Heart and Lung Institute, Imperial College London, London, SW7 2AZ, UK
| | - Teresa D Tetley
- National Heart and Lung Institute, Imperial College London, London, SW7 2AZ, UK.
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15
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Hu JY, Yang P, Wegner DJ, Heins HB, Luke CJ, Li F, White FV, Silverman GA, Cole FS, Wambach JA. Functional characterization of four ATP-binding cassette transporter A3 gene (ABCA3) variants. Hum Mutat 2020; 41:1298-1307. [PMID: 32196812 PMCID: PMC7292786 DOI: 10.1002/humu.24014] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2019] [Revised: 03/08/2020] [Accepted: 03/17/2020] [Indexed: 12/30/2022]
Abstract
ABCA3 transports phospholipids across lamellar body membranes in pulmonary alveolar type II cells and is required for surfactant assembly. Rare, biallelic, pathogenic ABCA3 variants result in lethal neonatal respiratory distress syndrome and childhood interstitial lung disease. Qualitative functional characterization of ABCA3 missense variants suggests two pathogenic classes: disrupted intracellular trafficking (type I mutant) or impaired ATPase-mediated phospholipid transport into the lamellar bodies (type II mutant). We qualitatively compared wild-type (WT-ABCA3) with four uncharacterized ABCA3 variants (c.418A>C;p.Asn140His, c.3609_3611delCTT;p.Phe1203del, c.3784A>G;p.Ser1262Gly, and c.4195G>A;p.Val1399Met) in A549 cells using protein processing, colocalization with intracellular organelles, lamellar body ultrastructure, and ATPase activity. We quantitatively measured lamellar body-like vesicle diameter and intracellular ABCA3 trafficking using fluorescence-based colocalization. Three ABCA3 variants (p.Asn140His, p.Ser1262Gly, and p.Val1399Met) were processed and trafficked normally and demonstrated well-organized lamellar body-like vesicles, but had reduced ATPase activity consistent with type II mutants. P.Phe1203del was processed normally, had reduced ATPase activity, and well-organized lamellar body-like vesicles, but quantitatively colocalized with both endoplasmic reticulum and lysosomal markers, an intermediate phenotype suggesting disruption of both intracellular trafficking and phospholipid transport. All ABCA3 mutants demonstrated mean vesicle diameters smaller than WT-ABCA3. Qualitative and quantitative functional characterization of ABCA3 variants informs mechanisms of pathogenicity.
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Affiliation(s)
- June Y. Hu
- Edward Mallinckrodt Department of Pediatrics, Washington University School of Medicine, St. Louis, Missouri
| | - Ping Yang
- Edward Mallinckrodt Department of Pediatrics, Washington University School of Medicine, St. Louis, Missouri
| | - Daniel J. Wegner
- Edward Mallinckrodt Department of Pediatrics, Washington University School of Medicine, St. Louis, Missouri
| | - Hillary B. Heins
- Edward Mallinckrodt Department of Pediatrics, Washington University School of Medicine, St. Louis, Missouri
| | - Cliff J. Luke
- Edward Mallinckrodt Department of Pediatrics, Washington University School of Medicine, St. Louis, Missouri
| | - Fuhai Li
- Institute for Informatics, Washington University School of Medicine, St. Louis, Missouri
| | - Frances V. White
- Department of Pathology and Immunology, Washington University School of Medicine, St. Louis, Missouri
| | - Gary A. Silverman
- Edward Mallinckrodt Department of Pediatrics, Washington University School of Medicine, St. Louis, Missouri
| | - F. Sessions Cole
- Edward Mallinckrodt Department of Pediatrics, Washington University School of Medicine, St. Louis, Missouri
| | - Jennifer A. Wambach
- Edward Mallinckrodt Department of Pediatrics, Washington University School of Medicine, St. Louis, Missouri
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16
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Greaney AM, Adams TS, Brickman Raredon MS, Gubbins E, Schupp JC, Engler AJ, Ghaedi M, Yuan Y, Kaminski N, Niklason LE. Platform Effects on Regeneration by Pulmonary Basal Cells as Evaluated by Single-Cell RNA Sequencing. Cell Rep 2020; 30:4250-4265.e6. [PMID: 32209482 PMCID: PMC7175071 DOI: 10.1016/j.celrep.2020.03.004] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2019] [Revised: 09/24/2019] [Accepted: 03/02/2020] [Indexed: 12/16/2022] Open
Abstract
Cell-based therapies have shown promise for treating myriad chronic pulmonary diseases through direct application of epithelial progenitors or by way of engineered tissue grafts or whole organs. To elucidate environmental effects on epithelial regenerative outcomes in vitro, here, we isolate and culture a population of pharmacologically expanded basal cells (peBCs) from rat tracheas. At peak basal marker expression, we simultaneously split peBCs into four in vitro platforms: organoid, air-liquid interface (ALI), engineered trachea, and engineered lung. Following differentiation, these samples are evaluated using single-cell RNA sequencing (scRNA-seq) and computational pipelines are developed to compare samples both globally and at the population level. A sample of native rat tracheal epithelium is also evaluated by scRNA-seq as a control for engineered epithelium. Overall, this work identifies platform-specific effects that support the use of engineered models to achieve the most physiologic differential outcomes in pulmonary epithelial regenerative applications.
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Affiliation(s)
- Allison M Greaney
- Department of Biomedical Engineering, Yale University, New Haven, CT 06511, USA; Vascular Biology and Therapeutics, Yale University, New Haven, CT 06511, USA.
| | - Taylor S Adams
- Section of Pulmonary, Critical Care, and Sleep Medicine, Yale School of Medicine, New Haven, CT 06519, USA
| | - Micha Sam Brickman Raredon
- Department of Biomedical Engineering, Yale University, New Haven, CT 06511, USA; Vascular Biology and Therapeutics, Yale University, New Haven, CT 06511, USA; Medical Scientist Training Program, Yale University, New Haven, CT 06511, USA
| | - Elise Gubbins
- Department of Biomedical Engineering, Yale University, New Haven, CT 06511, USA
| | - Jonas C Schupp
- Section of Pulmonary, Critical Care, and Sleep Medicine, Yale School of Medicine, New Haven, CT 06519, USA
| | - Alexander J Engler
- Department of Biomedical Engineering, Yale University, New Haven, CT 06511, USA; Vascular Biology and Therapeutics, Yale University, New Haven, CT 06511, USA
| | - Mahboobe Ghaedi
- Vascular Biology and Therapeutics, Yale University, New Haven, CT 06511, USA; Department of Anesthesiology, Yale University, New Haven, CT 06510, USA
| | - Yifan Yuan
- Vascular Biology and Therapeutics, Yale University, New Haven, CT 06511, USA; Department of Anesthesiology, Yale University, New Haven, CT 06510, USA
| | - Naftali Kaminski
- Section of Pulmonary, Critical Care, and Sleep Medicine, Yale School of Medicine, New Haven, CT 06519, USA
| | - Laura E Niklason
- Department of Biomedical Engineering, Yale University, New Haven, CT 06511, USA; Vascular Biology and Therapeutics, Yale University, New Haven, CT 06511, USA; Department of Anesthesiology, Yale University, New Haven, CT 06510, USA
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17
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Voss L, Foster OK, Harper L, Morris C, Lavoy S, Brandt JN, Peloza K, Handa S, Maxfield A, Harp M, King B, Eichten V, Rambo FM, Hermann GJ. An ABCG Transporter Functions in Rab Localization and Lysosome-Related Organelle Biogenesis in Caenorhabditis elegans. Genetics 2020; 214:419-445. [PMID: 31848222 PMCID: PMC7017009 DOI: 10.1534/genetics.119.302900] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2019] [Accepted: 12/11/2019] [Indexed: 12/20/2022] Open
Abstract
ABC transporters couple ATP hydrolysis to the transport of substrates across cellular membranes. This protein superfamily has diverse activities resulting from differences in their cargo and subcellular localization. Our work investigates the role of the ABCG family member WHT-2 in the biogenesis of gut granules, a Caenorhabditis elegans lysosome-related organelle. In addition to being required for the accumulation of birefringent material within gut granules, WHT-2 is necessary for the localization of gut granule proteins when trafficking pathways to this organelle are partially disrupted. The role of WHT-2 in gut granule protein targeting is likely linked to its function in Rab GTPase localization. We show that WHT-2 promotes the gut granule association of the Rab32 family member GLO-1 and the endolysosomal RAB-7, identifying a novel function for an ABC transporter. WHT-2 localizes to gut granules where it could play a direct role in controlling Rab localization. Loss of CCZ-1 and GLO-3, which likely function as a guanine nucleotide exchange factor (GEF) for GLO-1, lead to similar disruption of GLO-1 localization. We show that CCZ-1, like GLO-3, is localized to gut granules. WHT-2 does not direct the gut granule association of the GLO-1 GEF and our results point to WHT-2 functioning differently than GLO-3 and CCZ-1 Point mutations in WHT-2 that inhibit its transport activity, but not its subcellular localization, lead to the loss of GLO-1 from gut granules, while other WHT-2 activities are not completely disrupted, suggesting that WHT-2 functions in organelle biogenesis through transport-dependent and transport-independent activities.
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Affiliation(s)
- Laura Voss
- Department of Biology, Lewis & Clark College, Portland, Oregon
| | - Olivia K Foster
- Department of Biology, Lewis & Clark College, Portland, Oregon
| | - Logan Harper
- Department of Biology, Lewis & Clark College, Portland, Oregon
| | - Caitlin Morris
- Department of Biology, Lewis & Clark College, Portland, Oregon
| | - Sierra Lavoy
- Department of Biology, Lewis & Clark College, Portland, Oregon
| | - James N Brandt
- Department of Biology, Lewis & Clark College, Portland, Oregon
| | - Kimberly Peloza
- Department of Biology, Lewis & Clark College, Portland, Oregon
| | - Simran Handa
- Department of Biology, Lewis & Clark College, Portland, Oregon
| | - Amanda Maxfield
- Department of Biology, Lewis & Clark College, Portland, Oregon
| | - Marie Harp
- Department of Biology, Lewis & Clark College, Portland, Oregon
| | - Brian King
- Department of Biology, Lewis & Clark College, Portland, Oregon
| | | | - Fiona M Rambo
- Department of Biology, Lewis & Clark College, Portland, Oregon
| | - Greg J Hermann
- Department of Biology, Lewis & Clark College, Portland, Oregon
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18
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Adverse impact of ambient PM2.5 on expression and trafficking of surfactant protein A through reactive oxygen species damage to lamellar bodies. Toxicol Lett 2019; 315:47-54. [DOI: 10.1016/j.toxlet.2019.08.015] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2019] [Revised: 08/15/2019] [Accepted: 08/19/2019] [Indexed: 01/01/2023]
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19
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Kook S, Qi A, Wang P, Meng S, Gulleman P, Young LR, Guttentag SH. Gene-edited MLE-15 Cells as a Model for the Hermansky-Pudlak Syndromes. Am J Respir Cell Mol Biol 2019; 58:566-574. [PMID: 29190429 DOI: 10.1165/rcmb.2017-0324ma] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
Defining the mechanisms of cellular pathogenesis in rare lung diseases such as Hermansky-Pudlak syndrome (HPS) is often complicated by loss of the differentiated phenotype of cultured primary alveolar type 2 (AT2) cells, as well as by a lack of durable cell lines that are faithful to both AT2-cell and rare disease phenotypes. We used CRISPR/Cas9 gene editing to generate a series of HPS-specific mutations in the MLE-15 cell line. The resulting MLE-15/HPS cell lines exhibit preservation of AT2 cellular functions, including formation of lamellar body-like organelles, complete processing of surfactant protein B, and known features of HPS specific to each trafficking complex, including loss of protein targeting to lamellar bodies. MLE-15/HPS1 and MLE-15/HPS2 (with a mutation in Ap3β1) express increased macrophage chemotactic protein-1, a well-described mediator of alveolitis in patients with HPS and in mouse models. We show that MLE-15/HPS9 and pallid AT2 cells (with a mutation in Bloc1s6) also express increased macrophage chemotactic protein-1, suggesting that mice and humans with BLOC-1 mutations may also be susceptible to alveolitis. In addition to providing a flexible platform to examine the role of HPS-specific mutations in trafficking AT2 cells, MLE-15/HPS cell lines provide a durable resource for high-throughput screening and studies of cellular pathophysiology that are likely to accelerate progress toward developing novel therapies for this rare lung disease.
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Affiliation(s)
| | - Aidong Qi
- 2 Division of Pediatric Pulmonary Medicine, Department of Pediatrics, Vanderbilt University School of Medicine, Nashville, Tennessee
| | | | | | - Peter Gulleman
- 2 Division of Pediatric Pulmonary Medicine, Department of Pediatrics, Vanderbilt University School of Medicine, Nashville, Tennessee
| | - Lisa R Young
- 2 Division of Pediatric Pulmonary Medicine, Department of Pediatrics, Vanderbilt University School of Medicine, Nashville, Tennessee
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20
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Rampanelli E, Ochodnicky P, Vissers JP, Butter LM, Claessen N, Calcagni A, Kors L, Gethings LA, Bakker SJ, de Borst MH, Navis GJ, Liebisch G, Speijer D, van den Bergh Weerman MA, Jung B, Aten J, Steenbergen E, Schmitz G, Ballabio A, Florquin S, Aerts JM, Leemans JC. Excessive dietary lipid intake provokes an acquired form of lysosomal lipid storage disease in the kidney. J Pathol 2018; 246:470-484. [PMID: 30073645 DOI: 10.1002/path.5150] [Citation(s) in RCA: 32] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2017] [Revised: 06/15/2018] [Accepted: 07/30/2018] [Indexed: 12/14/2022]
Abstract
Obesity and dyslipidaemia are features of the metabolic syndrome and risk factors for chronic kidney disease. The cellular mechanisms connecting metabolic syndrome with chronic kidney disease onset and progression remain largely unclear. We show that proximal tubular epithelium is a target site for lipid deposition upon overnutrition with a cholesterol-rich Western-type diet. Affected proximal tubule epithelial cells displayed giant vacuoles of lysosomal or autophagosomal origin, harbouring oxidised lipoproteins and concentric membrane layer structures (multilamellar bodies), reminiscent of lysosomal storage diseases. Additionally, lipidomic analysis revealed renal deposition of cholesterol and phospholipids, including lysosomal phospholipids. Proteomic profiles of renal multilamellar bodies were distinct from those of epidermis or lung multilamellar bodies and of cytoplasmic lipid droplets. Tubular multilamellar bodies were observed in kidney biopsies of obese hypercholesterolaemic patients, and the concentration of the phospholipidosis marker di-docosahexaenoyl (22:6)-bis(monoacylglycerol) phosphate was doubled in urine from individuals with metabolic syndrome and chronic kidney disease. The enrichment of proximal tubule epithelial cells with phospholipids and multilamellar bodies was accompanied by enhanced inflammation, fibrosis, tubular damage markers, and higher urinary electrolyte content. Concomitantly to the intralysosomal lipid storage, a renal transcriptional response was initiated to enhance lysosomal degradation and lipid synthesis. In cultured proximal tubule epithelial cells, inhibition of cholesterol efflux transport or oxysterol treatment induced effects very similar to the in vivo situation, such as multilamellar body and phospholipid amassing, and induction of damage, inflammatory, fibrotic, and lipogenic molecules. The onset of phospholipidosis in proximal tubule epithelial cells is a novel pathological trait in metabolic syndrome-related chronic kidney disease, and emphasises the importance of healthy lysosomes and nutrition for kidney well-being. Copyright © 2018 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.
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Affiliation(s)
- Elena Rampanelli
- Pathology Department, Academic Medical Center, University of Amsterdam, Amsterdam, The Netherlands
| | - Peter Ochodnicky
- Pathology Department, Academic Medical Center, University of Amsterdam, Amsterdam, The Netherlands
| | | | - Loes M Butter
- Pathology Department, Academic Medical Center, University of Amsterdam, Amsterdam, The Netherlands
| | - Nike Claessen
- Pathology Department, Academic Medical Center, University of Amsterdam, Amsterdam, The Netherlands
| | - Alessia Calcagni
- Department of Translational Medicine, Telethon Institute of Genetics and Medicine (TIGEM) & Medical Genetics, Federico II University, Naples, Italy
| | - Lotte Kors
- Pathology Department, Academic Medical Center, University of Amsterdam, Amsterdam, The Netherlands
| | | | - Stephan Jl Bakker
- Division of Nephrology, Department of Internal Medicine, University Medical Center Groningen, University of Groningen, Groningen, The Netherlands
| | - Martin H de Borst
- Division of Nephrology, Department of Internal Medicine, University Medical Center Groningen, University of Groningen, Groningen, The Netherlands
| | - Gerjan J Navis
- Division of Nephrology, Department of Internal Medicine, University Medical Center Groningen, University of Groningen, Groningen, The Netherlands
| | - Gerhard Liebisch
- Division of Clinical Chemistry and Laboratory Medicine, University Hospital of Regensburg, Regensburg, Germany
| | - Dave Speijer
- Department of Medical Biochemistry, Academic Medical Center, University of Amsterdam, Amsterdam, The Netherlands
| | | | - Bettina Jung
- Division of Nephrology, University Hospital of Regensburg, Regensburg, Germany
| | - Jan Aten
- Pathology Department, Academic Medical Center, University of Amsterdam, Amsterdam, The Netherlands
| | - Eric Steenbergen
- Department of Pathology, RIMLS, RIHS, Radboud University Medical Center, Nijmegen, The Netherlands
| | - Gerd Schmitz
- Division of Clinical Chemistry and Laboratory Medicine, University Hospital of Regensburg, Regensburg, Germany
| | - Andrea Ballabio
- Department of Translational Medicine, Telethon Institute of Genetics and Medicine (TIGEM) & Medical Genetics, Federico II University, Naples, Italy
| | - Sandrine Florquin
- Pathology Department, Academic Medical Center, University of Amsterdam, Amsterdam, The Netherlands
| | - Johannes Mfg Aerts
- Department of Biochemistry, Leiden Institute of Chemistry, Leiden University, Leiden, The Netherlands
| | - Jaklien C Leemans
- Pathology Department, Academic Medical Center, University of Amsterdam, Amsterdam, The Netherlands
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21
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Abstract
Murrell-Lagnado provides insight into new research revealing the physiological role of lysosomal P2X4 channels.
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Affiliation(s)
- Ruth D Murrell-Lagnado
- Sussex Neuroscience, School of Life Sciences, University of Sussex, Brighton, England, UK
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22
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Tang X, Snowball JM, Xu Y, Na CL, Weaver TE, Clair G, Kyle JE, Zink EM, Ansong C, Wei W, Huang M, Lin X, Whitsett JA. EMC3 coordinates surfactant protein and lipid homeostasis required for respiration. J Clin Invest 2017; 127:4314-4325. [PMID: 29083321 DOI: 10.1172/jci94152] [Citation(s) in RCA: 38] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2017] [Accepted: 09/26/2017] [Indexed: 01/30/2023] Open
Abstract
Adaptation to respiration at birth depends upon the synthesis of pulmonary surfactant, a lipid-protein complex that reduces surface tension at the air-liquid interface in the alveoli and prevents lung collapse during the ventilatory cycle. Herein, we demonstrated that the gene encoding a subunit of the endoplasmic reticulum membrane complex, EMC3, also known as TMEM111 (Emc3/Tmem111), was required for murine pulmonary surfactant synthesis and lung function at birth. Conditional deletion of Emc3 in murine embryonic lung epithelial cells disrupted the synthesis and packaging of surfactant lipids and proteins, impaired the formation of lamellar bodies, and induced the unfolded protein response in alveolar type 2 (AT2) cells. EMC3 was essential for the processing and routing of surfactant proteins, SP-B and SP-C, and the biogenesis of the phospholipid transport protein ABCA3. Transcriptomic, lipidomic, and proteomic analyses demonstrated that EMC3 coordinates the assembly of lipids and proteins in AT2 cells that is necessary for surfactant synthesis and function at birth.
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Affiliation(s)
- Xiaofang Tang
- Divisions of Neonatology, Perinatal and Pulmonary Biology, Perinatal Institute, Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio, USA
| | - John M Snowball
- Divisions of Neonatology, Perinatal and Pulmonary Biology, Perinatal Institute, Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio, USA
| | - Yan Xu
- Divisions of Neonatology, Perinatal and Pulmonary Biology, Perinatal Institute, Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio, USA
| | - Cheng-Lun Na
- Divisions of Neonatology, Perinatal and Pulmonary Biology, Perinatal Institute, Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio, USA
| | - Timothy E Weaver
- Divisions of Neonatology, Perinatal and Pulmonary Biology, Perinatal Institute, Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio, USA
| | - Geremy Clair
- Biological Sciences Division, Pacific Northwest National Laboratory, Richland, Washington, USA
| | - Jennifer E Kyle
- Biological Sciences Division, Pacific Northwest National Laboratory, Richland, Washington, USA
| | - Erika M Zink
- Biological Sciences Division, Pacific Northwest National Laboratory, Richland, Washington, USA
| | - Charles Ansong
- Biological Sciences Division, Pacific Northwest National Laboratory, Richland, Washington, USA
| | - Wei Wei
- State Key Laboratory of Genetic Engineering, Institute of Genetics, Collaborative Innovation Center of Genetics and Development, School of Life Sciences, Fudan University, Shanghai, China
| | - Meina Huang
- State Key Laboratory of Genetic Engineering, Institute of Genetics, Collaborative Innovation Center of Genetics and Development, School of Life Sciences, Fudan University, Shanghai, China
| | - Xinhua Lin
- State Key Laboratory of Genetic Engineering, Institute of Genetics, Collaborative Innovation Center of Genetics and Development, School of Life Sciences, Fudan University, Shanghai, China.,Division of Developmental Biology, Perinatal Institute, Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio, USA
| | - Jeffrey A Whitsett
- Divisions of Neonatology, Perinatal and Pulmonary Biology, Perinatal Institute, Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio, USA
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23
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Jacob A, Morley M, Hawkins F, McCauley KB, Jean JC, Heins H, Na CL, Weaver TE, Vedaie M, Hurley K, Hinds A, Russo SJ, Kook S, Zacharias W, Ochs M, Traber K, Quinton LJ, Crane A, Davis BR, White FV, Wambach J, Whitsett JA, Cole FS, Morrisey EE, Guttentag SH, Beers MF, Kotton DN. Differentiation of Human Pluripotent Stem Cells into Functional Lung Alveolar Epithelial Cells. Cell Stem Cell 2017; 21:472-488.e10. [PMID: 28965766 PMCID: PMC5755620 DOI: 10.1016/j.stem.2017.08.014] [Citation(s) in RCA: 330] [Impact Index Per Article: 47.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2017] [Revised: 06/21/2017] [Accepted: 08/18/2017] [Indexed: 02/01/2023]
Abstract
Lung alveoli, which are unique to air-breathing organisms, have been challenging to generate from pluripotent stem cells (PSCs) in part because there are limited model systems available to provide the necessary developmental roadmaps for in vitro differentiation. Here we report the generation of alveolar epithelial type 2 cells (AEC2s), the facultative progenitors of lung alveoli, from human PSCs. Using multicolored fluorescent reporter lines, we track and purify human SFTPC+ alveolar progenitors as they emerge from endodermal precursors in response to stimulation of Wnt and FGF signaling. Purified PSC-derived SFTPC+ cells form monolayered epithelial "alveolospheres" in 3D cultures without the need for mesenchymal support, exhibit self-renewal capacity, and display additional AEC2 functional capacities. Footprint-free CRISPR-based gene correction of PSCs derived from patients carrying a homozygous surfactant mutation (SFTPB121ins2) restores surfactant processing in AEC2s. Thus, PSC-derived AEC2s provide a platform for disease modeling and future functional regeneration of the distal lung.
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Affiliation(s)
- Anjali Jacob
- Center for Regenerative Medicine of Boston University and Boston Medical Center, Boston, MA 02118, USA; The Pulmonary Center and Department of Medicine, Boston University School of Medicine, Boston, MA 02118, USA
| | - Michael Morley
- Penn Center for Pulmonary Biology, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Finn Hawkins
- Center for Regenerative Medicine of Boston University and Boston Medical Center, Boston, MA 02118, USA; The Pulmonary Center and Department of Medicine, Boston University School of Medicine, Boston, MA 02118, USA
| | - Katherine B McCauley
- Center for Regenerative Medicine of Boston University and Boston Medical Center, Boston, MA 02118, USA; The Pulmonary Center and Department of Medicine, Boston University School of Medicine, Boston, MA 02118, USA
| | - J C Jean
- Center for Regenerative Medicine of Boston University and Boston Medical Center, Boston, MA 02118, USA; The Pulmonary Center and Department of Medicine, Boston University School of Medicine, Boston, MA 02118, USA
| | - Hillary Heins
- Edward Mallinckrodt Department of Pediatrics, Washington University School of Medicine, St. Louis, MO 63110, USA
| | - Cheng-Lun Na
- Division of Pulmonary Biology, Cincinnati Children's Hospital Medical Center, Cincinnati, OH 45229, USA
| | - Timothy E Weaver
- Division of Pulmonary Biology, Cincinnati Children's Hospital Medical Center, Cincinnati, OH 45229, USA
| | - Marall Vedaie
- Center for Regenerative Medicine of Boston University and Boston Medical Center, Boston, MA 02118, USA; The Pulmonary Center and Department of Medicine, Boston University School of Medicine, Boston, MA 02118, USA
| | - Killian Hurley
- Center for Regenerative Medicine of Boston University and Boston Medical Center, Boston, MA 02118, USA; The Pulmonary Center and Department of Medicine, Boston University School of Medicine, Boston, MA 02118, USA
| | - Anne Hinds
- The Pulmonary Center and Department of Medicine, Boston University School of Medicine, Boston, MA 02118, USA
| | - Scott J Russo
- Penn Center for Pulmonary Biology, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Seunghyi Kook
- Department of Pediatrics, Monroe Carell Jr. Children's Hospital, Vanderbilt University, Nashville, TN 37232, USA
| | - William Zacharias
- Penn Center for Pulmonary Biology, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Matthias Ochs
- Institute of Functional and Applied Anatomy, Hannover Medical School, Biomedical Research in Endstage and Obstructive Lung Disease Hannover (BREATH), Member of the German Center for Lung Research (DZL), REBIRTH Cluster of Excellence, 30625 Hannover, Germany
| | - Katrina Traber
- The Pulmonary Center and Department of Medicine, Boston University School of Medicine, Boston, MA 02118, USA
| | - Lee J Quinton
- The Pulmonary Center and Department of Medicine, Boston University School of Medicine, Boston, MA 02118, USA
| | - Ana Crane
- Center for Stem Cell and Regenerative Medicine, Brown Foundation Institute of Molecular Medicine, University of Texas Health Science Center, Houston, TX 77030, USA
| | - Brian R Davis
- Center for Stem Cell and Regenerative Medicine, Brown Foundation Institute of Molecular Medicine, University of Texas Health Science Center, Houston, TX 77030, USA
| | - Frances V White
- Edward Mallinckrodt Department of Pediatrics, Washington University School of Medicine, St. Louis, MO 63110, USA
| | - Jennifer Wambach
- Edward Mallinckrodt Department of Pediatrics, Washington University School of Medicine, St. Louis, MO 63110, USA
| | - Jeffrey A Whitsett
- Division of Pulmonary Biology, Cincinnati Children's Hospital Medical Center, Cincinnati, OH 45229, USA
| | - F Sessions Cole
- Edward Mallinckrodt Department of Pediatrics, Washington University School of Medicine, St. Louis, MO 63110, USA
| | - Edward E Morrisey
- Penn Center for Pulmonary Biology, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Susan H Guttentag
- Department of Pediatrics, Monroe Carell Jr. Children's Hospital, Vanderbilt University, Nashville, TN 37232, USA
| | - Michael F Beers
- Penn Center for Pulmonary Biology, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Darrell N Kotton
- Center for Regenerative Medicine of Boston University and Boston Medical Center, Boston, MA 02118, USA; The Pulmonary Center and Department of Medicine, Boston University School of Medicine, Boston, MA 02118, USA.
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24
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Osanai K, Nakase K, Sakuma T, Nishiki K, Nojiri M, Kato R, Saito M, Fujimoto Y, Mizuno S, Toga H. Exogenous gene transfer of Rab 38 small GTPase ameliorates aberrant lung surfactant homeostasis in Ruby rats. Respir Res 2017; 18:70. [PMID: 28438206 PMCID: PMC5402648 DOI: 10.1186/s12931-017-0549-2] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2017] [Accepted: 04/11/2017] [Indexed: 11/25/2022] Open
Abstract
Background Rab38 small GTPase regulates intracellular transport in melanocytes and alveolar type II epithelial cells. Ruby rats carrying Rab38 and other gene mutations exhibit oculocutaneous albinism, bleeding diathesis, and hence, are a rat model of human Hermansky-Pudlak syndrome (HPS). We previously showed that Long Evans Cinnamon (LEC) rats, one strain of the Ruby rats, developed aberrant lung surfactant homeostasis with remarkably enlarged lamellar bodies in alveolar type II cells. Methods A replication-deficient recombinant adenovirus expressing rat Rab38 (Ad-Rab38) was constructed. Alveolar type II cells were isolated from the LEC rats and tested for lung surfactant phosphatidylcholine secretion. The rats were also examined whether exogenous expression of Ad- Rab38 could rescue the altered lung surfactant homeostasis in the lungs. Results Isolated type II cells infected with Ad-Rab38 exhibited improved secretion patterns of [3H]phosphatidylcholine, i.e. increased basal hyposecretion and decreased agonist-induced hypersecretion. Endobronchial administration of Ad-Rab38 improved the morphology of type II cells and lamellar bodies, reducing their sizes close to those of wild-type rats. The increased amounts of phosphatidylcholine and surfactant protein B in the lamellar body fractions were decreased in the Ad-Rab38 infected lungs. Conclusions These results provide strong evidence that the aberrant lung surfactant homeostasis in the LEC rats is caused by Rab38 deficit, and suggest that endobronchial delivery of the responsive transgene could be an effective method to ameliorate the abnormal lung phenotype in the animal model of HPS.
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Affiliation(s)
- Kazuhiro Osanai
- Department of Respiratory Medicine, Kanazawa Medical University, 1-1 Uchinada-Daigaku, Kahokugun, Ishikawa, 920-0293, Japan.
| | - Keisuke Nakase
- Department of Respiratory Medicine, Kanazawa Medical University, 1-1 Uchinada-Daigaku, Kahokugun, Ishikawa, 920-0293, Japan
| | - Takashi Sakuma
- Department of Respiratory Medicine, Kanazawa Medical University, 1-1 Uchinada-Daigaku, Kahokugun, Ishikawa, 920-0293, Japan
| | - Kazuaki Nishiki
- Department of Respiratory Medicine, Kanazawa Medical University, 1-1 Uchinada-Daigaku, Kahokugun, Ishikawa, 920-0293, Japan
| | - Masafumi Nojiri
- Department of Respiratory Medicine, Kanazawa Medical University, 1-1 Uchinada-Daigaku, Kahokugun, Ishikawa, 920-0293, Japan
| | - Ryo Kato
- Department of Respiratory Medicine, Kanazawa Medical University, 1-1 Uchinada-Daigaku, Kahokugun, Ishikawa, 920-0293, Japan
| | - Masatoshi Saito
- Department of Respiratory Medicine, Kanazawa Medical University, 1-1 Uchinada-Daigaku, Kahokugun, Ishikawa, 920-0293, Japan
| | - Yuki Fujimoto
- Department of Respiratory Medicine, Kanazawa Medical University, 1-1 Uchinada-Daigaku, Kahokugun, Ishikawa, 920-0293, Japan
| | - Shiro Mizuno
- Department of Respiratory Medicine, Kanazawa Medical University, 1-1 Uchinada-Daigaku, Kahokugun, Ishikawa, 920-0293, Japan
| | - Hirohisa Toga
- Department of Respiratory Medicine, Kanazawa Medical University, 1-1 Uchinada-Daigaku, Kahokugun, Ishikawa, 920-0293, Japan
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25
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Olmeda B, Martínez-Calle M, Pérez-Gil J. Pulmonary surfactant metabolism in the alveolar airspace: Biogenesis, extracellular conversions, recycling. Ann Anat 2016; 209:78-92. [PMID: 27773772 DOI: 10.1016/j.aanat.2016.09.008] [Citation(s) in RCA: 73] [Impact Index Per Article: 9.1] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2016] [Revised: 09/22/2016] [Accepted: 09/25/2016] [Indexed: 01/03/2023]
Abstract
Pulmonary surfactant is a lipid-protein complex that lines and stabilizes the respiratory interface in the alveoli, allowing for gas exchange during the breathing cycle. At the same time, surfactant constitutes the first line of lung defense against pathogens. This review presents an updated view on the processes involved in biogenesis and intracellular processing of newly synthesized and recycled surfactant components, as well as on the extracellular surfactant transformations before and after the formation of the surface active film at the air-water interface. Special attention is paid to the crucial regulation of surfactant homeostasis, because its disruption is associated with several lung pathologies.
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Affiliation(s)
- Bárbara Olmeda
- Department of Biochemistry, Faculty of Biology, and Research Institute "Hospital 12 de Octubre", Complutense University, 28040 Madrid, Spain
| | - Marta Martínez-Calle
- Department of Biochemistry, Faculty of Biology, and Research Institute "Hospital 12 de Octubre", Complutense University, 28040 Madrid, Spain
| | - Jesus Pérez-Gil
- Department of Biochemistry, Faculty of Biology, and Research Institute "Hospital 12 de Octubre", Complutense University, 28040 Madrid, Spain.
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26
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Abstract
The early/recycling endosomes of an eukaryotic cell perform diverse cellular functions. In addition, the endosomal system generates multiple organelles, including certain cell type-specific organelles called lysosome-related organelles (LROs). The biosynthesis of these organelles possibly occurs through a sequential maturation process in which the cargo-containing endosomal vesicular/tubular structures are fused with the maturing organelle. The molecular machinery that regulates the cargo delivery or the membrane fusion during LRO biogenesis is poorly understood. Here, we describe the known key molecules, such as SNAREs, that regulate both the biogenesis and secretion of multiple LROs. Moreover, we also describe other regulatory molecules, such as Rab GTPases and their effectors that modulate the SNARE activity for cargo delivery to one such LRO, the melanosome. Overall, this review will increase our current understanding of LRO biogenesis and function.
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Affiliation(s)
- Riddhi Atul Jani
- a Department of Microbiology and Cell Biology ; Indian Institute of Science ; Bangalore , India
| | - Sarmistha Mahanty
- a Department of Microbiology and Cell Biology ; Indian Institute of Science ; Bangalore , India
| | - Subba Rao Gangi Setty
- a Department of Microbiology and Cell Biology ; Indian Institute of Science ; Bangalore , India
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27
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Cerrada A, Haller T, Cruz A, Pérez-Gil J. Pneumocytes Assemble Lung Surfactant as Highly Packed/Dehydrated States with Optimal Surface Activity. Biophys J 2016; 109:2295-306. [PMID: 26636941 DOI: 10.1016/j.bpj.2015.10.022] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2015] [Revised: 10/08/2015] [Accepted: 10/13/2015] [Indexed: 01/22/2023] Open
Abstract
Pulmonary surfactant (PS) is an essential complex of lipids and specific proteins synthesized in alveolar type II pneumocytes, where it is assembled and stored intracellularly as multilayered organelles known as lamellar bodies (LBs). Once secreted upon physiological stimulation, LBs maintain a densely packed structure in the form of lamellar body-like particles (LBPs), which are efficiently transferred into the alveolar air-water interface, lowering surface tension to avoid lung collapse at end-expiration. In this work, the structural organization of membranes in LBs and LBPs freshly secreted by primary cultures of rat ATII cells has been compared with that of native lung surfactant membranes isolated from porcine bronchoalveolar lavage. PS assembles in LBs as crystalline-like highly ordered structures, with a highly packed and dehydrated state, which is maintained at supraphysiological temperatures. This relatively ordered/packed state is retained in secreted LBPs. The micro- and nanostructural examination of LBPs suggests the existence of high levels of structural complexity in comparison with the material purified from lavages, which may contain partially inactivated or spent structures. Additionally, freshly secreted surfactant LBPs exhibit superior activity when generating interfacial films and a higher intrinsic resistance to inactivating agents, such as serum proteins or meconium. We propose that LBs are assembled as an energy-activated structure competent to form very efficient interfacial films, and that the organization of lipids and proteins and the properties displayed by the films formed by LBPs are likely similar to those established at the alveolar interface and represent the actual functional structure of surfactant as it sustains respiration.
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Affiliation(s)
- Alejandro Cerrada
- Department of Biochemistry, Faculty of Biology, and Hospital 12 Octubre Research Institute, Universidad Complutense, Madrid, Spain
| | - Thomas Haller
- Department of Physiology and Medical Physics, Medical University of Innsbruck, Innsbruck, Austria
| | - Antonio Cruz
- Department of Biochemistry, Faculty of Biology, and Hospital 12 Octubre Research Institute, Universidad Complutense, Madrid, Spain
| | - Jesús Pérez-Gil
- Department of Biochemistry, Faculty of Biology, and Hospital 12 Octubre Research Institute, Universidad Complutense, Madrid, Spain.
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28
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Kook S, Wang P, Young LR, Schwake M, Saftig P, Weng X, Meng Y, Neculai D, Marks MS, Gonzales L, Beers MF, Guttentag S. Impaired Lysosomal Integral Membrane Protein 2-dependent Peroxiredoxin 6 Delivery to Lamellar Bodies Accounts for Altered Alveolar Phospholipid Content in Adaptor Protein-3-deficient pearl Mice. J Biol Chem 2016; 291:8414-27. [PMID: 26907692 PMCID: PMC4861416 DOI: 10.1074/jbc.m116.720201] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2016] [Indexed: 11/06/2022] Open
Abstract
The Hermansky Pudlak syndromes (HPS) constitute a family of disorders characterized by oculocutaneous albinism and bleeding diathesis, often associated with lethal lung fibrosis. HPS results from mutations in genes of membrane trafficking complexes that facilitate delivery of cargo to lysosome-related organelles. Among the affected lysosome-related organelles are lamellar bodies (LB) within alveolar type 2 cells (AT2) in which surfactant components are assembled, modified, and stored. AT2 from HPS patients and mouse models of HPS exhibit enlarged LB with increased phospholipid content, but the mechanism underlying these defects is unknown. We now show that AT2 in the pearl mouse model of HPS type 2 lacking the adaptor protein 3 complex (AP-3) fails to accumulate the soluble enzyme peroxiredoxin 6 (PRDX6) in LB. This defect reflects impaired AP-3-dependent trafficking of PRDX6 to LB, because pearl mouse AT2 cells harbor a normal total PRDX6 content. AP-3-dependent targeting of PRDX6 to LB requires the transmembrane protein LIMP-2/SCARB2, a known AP-3-dependent cargo protein that functions as a carrier for lysosomal proteins in other cell types. Depletion of LB PRDX6 in AP-3- or LIMP-2/SCARB2-deficient mice correlates with phospholipid accumulation in lamellar bodies and with defective intraluminal degradation of LB disaturated phosphatidylcholine. Furthermore, AP-3-dependent LB targeting is facilitated by protein/protein interaction between LIMP-2/SCARB2 and PRDX6 in vitro and in vivo Our data provide the first evidence for an AP-3-dependent cargo protein required for the maturation of LB in AT2 and suggest that the loss of PRDX6 activity contributes to the pathogenic changes in LB phospholipid homeostasis found HPS2 patients.
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Affiliation(s)
| | - Ping Wang
- From the Division of Neonatology and
| | - Lisa R Young
- Division of Pediatric Pulmonary Medicine, Department of Pediatrics, Vanderbilt University School of Medicine, Nashville, Tennessee 37232
| | - Michael Schwake
- the Department of Chemistry, Biochemistry III, University of Bielefeld, D-33615 Bielefeld, Germany
| | - Paul Saftig
- the Institute of Biochemistry, Christian-Albrechts-University, Olshausenstrasse 40, D-24098 Kiel, Germany
| | - Xialian Weng
- the Zhejiang University, Yuhangtang Road 866, Hangzhou 310058, China
| | - Ying Meng
- the Zhejiang University, Yuhangtang Road 866, Hangzhou 310058, China
| | - Dante Neculai
- the Zhejiang University, Yuhangtang Road 866, Hangzhou 310058, China
| | - Michael S Marks
- the Department of Pathology and Laboratory Medicine, The Children's Hospital of Philadelphia, Philadelphia, Pennsylvania 19104, and the Departments of Pathology and Laboratory Medicine and of Physiology, and
| | - Linda Gonzales
- Division of Adult Pulmonary and Critical Care Medicine, Department of Medicine, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania 19104
| | - Michael F Beers
- Division of Adult Pulmonary and Critical Care Medicine, Department of Medicine, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania 19104
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29
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Kittelberger N, Breunig M, Martin R, Knölker HJ, Miklavc P. The role of myosin 1c and myosin 1b in surfactant exocytosis. J Cell Sci 2016; 129:1685-96. [PMID: 26940917 PMCID: PMC4852769 DOI: 10.1242/jcs.181313] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2015] [Accepted: 02/25/2016] [Indexed: 12/19/2022] Open
Abstract
Actin and actin-associated proteins have a pivotal effect on regulated exocytosis in secretory cells and influence pre-fusion as well as post-fusion stages of exocytosis. Actin polymerization on secretory granules during the post-fusion phase (formation of an actin coat) is especially important in cells with large secretory vesicles or poorly soluble secretions. Alveolar type II (ATII) cells secrete hydrophobic lipo-protein surfactant, which does not easily diffuse from fused vesicles. Previous work showed that compression of actin coat is necessary for surfactant extrusion. Here, we investigate the role of class 1 myosins as possible linkers between actin and membranes during exocytosis. Live-cell microscopy showed translocation of fluorescently labeled myosin 1b and myosin 1c to the secretory vesicle membrane after fusion. Myosin 1c translocation was dependent on its pleckstrin homology domain. Expression of myosin 1b and myosin 1c constructs influenced vesicle compression rate, whereas only the inhibition of myosin 1c reduced exocytosis. These findings suggest that class 1 myosins participate in several stages of ATII cell exocytosis and link actin coats to the secretory vesicle membrane to influence vesicle compression.
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Affiliation(s)
- Nadine Kittelberger
- Institute of General Physiology, Ulm University, Albert-Einstein Allee 11, Ulm 89081, Germany
| | - Markus Breunig
- Institute of General Physiology, Ulm University, Albert-Einstein Allee 11, Ulm 89081, Germany
| | - René Martin
- Department of Chemistry, Technische Universität Dresden, Bergstr. 66, Dresden 01069, Germany
| | - Hans-Joachim Knölker
- Department of Chemistry, Technische Universität Dresden, Bergstr. 66, Dresden 01069, Germany
| | - Pika Miklavc
- Institute of General Physiology, Ulm University, Albert-Einstein Allee 11, Ulm 89081, Germany
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30
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Shimada H, Nakamura Y, Nakanishi T, Tamai I. OATP2A1/SLCO2A1-mediated prostaglandin E2 loading into intracellular acidic compartments of macrophages contributes to exocytotic secretion. Biochem Pharmacol 2015; 98:629-38. [PMID: 26474801 DOI: 10.1016/j.bcp.2015.10.009] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2015] [Accepted: 10/09/2015] [Indexed: 12/19/2022]
Abstract
There is significant evidence that the inducible cyclooxygenase isoform (COX-2) regulates the pericellular concentration of PGE2; however, the mechanism of the secretory process remains unclear. The present study, therefore, aimed to evaluate the role of prostaglandin transporter (OATP2A1) in PGE2 secretion from macrophages. Immunofluorescence staining for Oatp2a1 (Slco2a1) was primarily detected in cytoplasmic domains, and was partially co-localized with anti-PGE2 antibody, LysoTracker®, and anti-lysosome-associated membrane protein (Lamp) 1 antibody in murine macrophage-derived RAW264 cells and peritoneal macrophages (PMs). PGE2 uptake by subcellular fraction containing light lysosomes was reduced significantly in the presence of an OATP inhibitor and in Slco2a1(+/-) PMs. Secretion of PGE2 and lysosome-specific N-acetyl-β-d-glucosaminidase was enhanced in activated macrophagic cells, and diminished significantly under the Ca(2+)-depleted condition. The amount of PGE2 secreted from lipopolysaccharide-activated Slco2a1(-/-) PMs was significantly lower than that from PMs from wild type (WT) mice. Expression of Cox-2 and 15-hydroxyprostaglandin dehydrogenase (15-Pgdh) was unchanged between PMs from Slco2a1(-/-) and WT mice. These results suggest that OATP2A1 is involved in PGE2-loading into intracellular acidic compartments, including light lysosomes. Thus, OATP2A1 contributes to PGE2 secretion by macrophages via exocytosis induced by Ca(2+) influx, independently of PGE2 synthesis and metabolism.
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Affiliation(s)
- Hiroaki Shimada
- Department of Membrane Transport and Biopharmaceutics, Faculty of Pharmaceutical Science, Kanazawa University, Kakuma-machi, Kanazawa 920-1192, Japan
| | - Yoshinobu Nakamura
- Department of Membrane Transport and Biopharmaceutics, Faculty of Pharmaceutical Science, Kanazawa University, Kakuma-machi, Kanazawa 920-1192, Japan
| | - Takeo Nakanishi
- Department of Membrane Transport and Biopharmaceutics, Faculty of Pharmaceutical Science, Kanazawa University, Kakuma-machi, Kanazawa 920-1192, Japan.
| | - Ikumi Tamai
- Department of Membrane Transport and Biopharmaceutics, Faculty of Pharmaceutical Science, Kanazawa University, Kakuma-machi, Kanazawa 920-1192, Japan
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31
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Mahavadi P, Knudsen L, Venkatesan S, Henneke I, Hegermann J, Wrede C, Ochs M, Ahuja S, Chillappagari S, Ruppert C, Seeger W, Korfei M, Guenther A. Regulation of macroautophagy in amiodarone-induced pulmonary fibrosis. JOURNAL OF PATHOLOGY CLINICAL RESEARCH 2015; 1:252-63. [PMID: 27499909 PMCID: PMC4939895 DOI: 10.1002/cjp2.20] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/11/2014] [Accepted: 03/31/2015] [Indexed: 12/16/2022]
Abstract
Amiodarone (AD) is an iodinated benzofuran derivative, especially known for its antiarrhythmic properties. It exerts serious side‐effects even in patients receiving low doses. AD is well‐known to induce apoptosis of type II alveolar epithelial cells (AECII), a mechanism that has been suggested to play an important role in AD‐induced lung fibrosis. The precise molecular mechanisms underlying this disease are, however, still unclear. Because of its amphiphilic nature, AD becomes enriched in the lysosomal compartments, affecting the general functions of these organelles. Hence, in this study, we aimed to assess the role of autophagy, a lysosome‐dependent homeostasis mechanism, in driving AECII apoptosis in response to AD. In vitro, AD‐treated MLE12 and primary AECII cells showed increased proSP‐C and LC3B positive vacuolar structures and underwent LC3B‐dependent apoptosis. In addition, AD‐induced autophagosome‐lysosome fusion and increased autophagy flux were observed. In vivo, in C57BL/6 mice, LC3B was localised at the limiting membrane of lamellar bodies, which were closely connected to the autophagosomal structures in AECIIs. Our data suggest that AD causes activation of macroautophagy in AECIIs and extensive autophagy‐dependent apoptosis of alveolar epithelial cells. Targeting the autophagy pathway may therefore represent an attractive treatment modality in AD‐induced lung fibrosis.
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Affiliation(s)
- Poornima Mahavadi
- Department of Internal MedicineJustus-Liebig-UniversityGiessenGermany; Universities of Giessen and Marburg Lung Center (UGMLC), German Center for Lung Research (DZL)GiessenGermany
| | - Lars Knudsen
- Institute of Functional and Applied Anatomy, Hannover Medical SchoolHannoverGermany; Biomedical Research in Endstage and Obstructive Lung Disease Hannover (BREATH), German Center for Lung Research (DZL)HannoverGermany; REBIRTH Cluster of ExcellenceHannoverGermany
| | - Shalini Venkatesan
- Department of Internal MedicineJustus-Liebig-UniversityGiessenGermany; Universities of Giessen and Marburg Lung Center (UGMLC), German Center for Lung Research (DZL)GiessenGermany
| | - Ingrid Henneke
- Department of Internal MedicineJustus-Liebig-UniversityGiessenGermany; Universities of Giessen and Marburg Lung Center (UGMLC), German Center for Lung Research (DZL)GiessenGermany
| | - Jan Hegermann
- Institute of Functional and Applied Anatomy, Hannover Medical SchoolHannoverGermany; Biomedical Research in Endstage and Obstructive Lung Disease Hannover (BREATH), German Center for Lung Research (DZL)HannoverGermany; REBIRTH Cluster of ExcellenceHannoverGermany
| | - Christoph Wrede
- Institute of Functional and Applied Anatomy, Hannover Medical SchoolHannoverGermany; Biomedical Research in Endstage and Obstructive Lung Disease Hannover (BREATH), German Center for Lung Research (DZL)HannoverGermany; REBIRTH Cluster of ExcellenceHannoverGermany
| | - Matthias Ochs
- Institute of Functional and Applied Anatomy, Hannover Medical SchoolHannoverGermany; Biomedical Research in Endstage and Obstructive Lung Disease Hannover (BREATH), German Center for Lung Research (DZL)HannoverGermany; REBIRTH Cluster of ExcellenceHannoverGermany
| | - Saket Ahuja
- Department of Internal MedicineJustus-Liebig-UniversityGiessenGermany; Universities of Giessen and Marburg Lung Center (UGMLC), German Center for Lung Research (DZL)GiessenGermany
| | - Shashi Chillappagari
- Universities of Giessen and Marburg Lung Center (UGMLC), German Center for Lung Research (DZL)GiessenGermany; Department of Medicine, Pulmonary Critical CarePhilipps-Universität MarburgBaldingerstrasse 135043MarburgGermany
| | - Clemens Ruppert
- Department of Internal MedicineJustus-Liebig-UniversityGiessenGermany; Universities of Giessen and Marburg Lung Center (UGMLC), German Center for Lung Research (DZL)GiessenGermany
| | - Werner Seeger
- Department of Internal MedicineJustus-Liebig-UniversityGiessenGermany; Universities of Giessen and Marburg Lung Center (UGMLC), German Center for Lung Research (DZL)GiessenGermany; Member of the European IPF Network
| | - Martina Korfei
- Department of Internal MedicineJustus-Liebig-UniversityGiessenGermany; Universities of Giessen and Marburg Lung Center (UGMLC), German Center for Lung Research (DZL)GiessenGermany
| | - Andreas Guenther
- Department of Internal MedicineJustus-Liebig-UniversityGiessenGermany; Universities of Giessen and Marburg Lung Center (UGMLC), German Center for Lung Research (DZL)GiessenGermany; Member of the European IPF Network; Lung Clinic Waldhof-ElgershausenGreifensteinGermany
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32
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Rasmussen HB, Bjerre D, Linnet K, Jürgens G, Dalhoff K, Stefansson H, Hankemeier T, Kaddurah-Daouk R, Taboureau O, Brunak S, Houmann T, Jeppesen P, Pagsberg AK, Plessen K, Dyrborg J, Hansen PR, Hansen PE, Hughes T, Werge T. Individualization of treatments with drugs metabolized by CES1: combining genetics and metabolomics. Pharmacogenomics 2015; 16:649-65. [PMID: 25896426 DOI: 10.2217/pgs.15.7] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023] Open
Abstract
CES1 is involved in the hydrolysis of ester group-containing xenobiotic and endobiotic compounds including several essential and commonly used drugs. The individual variation in the efficacy and tolerability of many drugs metabolized by CES1 is considerable. Hence, there is a large interest in individualizing the treatment with these drugs. The present review addresses the issue of individualized treatment with drugs metabolized by CES1. It describes the composition of the gene encoding CES1, reports variants of this gene with focus upon those with a potential effect on drug metabolism and provides an overview of the protein structure of this enzyme bringing notice to mechanisms involved in the regulation of enzyme activity. Subsequently, the review highlights drugs metabolized by CES1 and argues that individual differences in the pharmacokinetics of these drugs play an important role in determining drug response and tolerability suggesting prospects for individualized drug therapies. Our review also discusses endogenous substrates of CES1 and assesses the potential of using metabolomic profiling of blood to identify proxies for the hepatic activity of CES1 that predict the rate of drug metabolism. Finally, the combination of genetics and metabolomics to obtain an accurate prediction of the individual response to CES1-dependent drugs is discussed.
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Affiliation(s)
- Henrik Berg Rasmussen
- Institute of Biological Psychiatry, Mental Health Centre Sct. Hans, Copenhagen University Hospital, 2 Boserupvej, DK-4000 Roskilde, Denmark
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33
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Hasegawa K, Sin HS, Maezawa S, Broering TJ, Kartashov AV, Alavattam KG, Ichijima Y, Zhang F, Bacon WC, Greis KD, Andreassen PR, Barski A, Namekawa SH. SCML2 establishes the male germline epigenome through regulation of histone H2A ubiquitination. Dev Cell 2015; 32:574-88. [PMID: 25703348 PMCID: PMC4391279 DOI: 10.1016/j.devcel.2015.01.014] [Citation(s) in RCA: 84] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2014] [Revised: 12/23/2014] [Accepted: 01/16/2015] [Indexed: 01/03/2023]
Abstract
Gametogenesis is dependent on the expression of germline-specific genes. However, it remains unknown how the germline epigenome is distinctly established from that of somatic lineages. Here we show that genes commonly expressed in somatic lineages and spermatogenesis-progenitor cells undergo repression in a genome-wide manner in late stages of the male germline and identify underlying mechanisms. SCML2, a germline-specific subunit of a Polycomb repressive complex 1 (PRC1), establishes the unique epigenome of the male germline through two distinct antithetical mechanisms. SCML2 works with PRC1 and promotes RNF2-dependent ubiquitination of H2A, thereby marking somatic/progenitor genes on autosomes for repression. Paradoxically, SCML2 also prevents RNF2-dependent ubiquitination of H2A on sex chromosomes during meiosis, thereby enabling unique epigenetic programming of sex chromosomes for male reproduction. Our results reveal divergent mechanisms involving a shared regulator by which the male germline epigenome is distinguished from that of the soma and progenitor cells.
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Affiliation(s)
- Kazuteru Hasegawa
- Division of Reproductive Sciences, Division of Developmental Biology, Perinatal Institute, Cincinnati Children's Hospital Medical Center, Cincinnati, OH 45229, USA; Department of Pediatrics, University of Cincinnati College of Medicine, Cincinnati, OH 49267, USA
| | - Ho-Su Sin
- Division of Reproductive Sciences, Division of Developmental Biology, Perinatal Institute, Cincinnati Children's Hospital Medical Center, Cincinnati, OH 45229, USA; Department of Pediatrics, University of Cincinnati College of Medicine, Cincinnati, OH 49267, USA
| | - So Maezawa
- Division of Reproductive Sciences, Division of Developmental Biology, Perinatal Institute, Cincinnati Children's Hospital Medical Center, Cincinnati, OH 45229, USA; Department of Pediatrics, University of Cincinnati College of Medicine, Cincinnati, OH 49267, USA
| | - Tyler J Broering
- Division of Reproductive Sciences, Division of Developmental Biology, Perinatal Institute, Cincinnati Children's Hospital Medical Center, Cincinnati, OH 45229, USA; Department of Pediatrics, University of Cincinnati College of Medicine, Cincinnati, OH 49267, USA
| | - Andrey V Kartashov
- Division of Allergy and Immunology, Division of Human Genetics, Cincinnati Children's Hospital Medical Center, Cincinnati, OH 45229, USA; Department of Pediatrics, University of Cincinnati College of Medicine, Cincinnati, OH 49267, USA
| | - Kris G Alavattam
- Division of Reproductive Sciences, Division of Developmental Biology, Perinatal Institute, Cincinnati Children's Hospital Medical Center, Cincinnati, OH 45229, USA; Department of Pediatrics, University of Cincinnati College of Medicine, Cincinnati, OH 49267, USA
| | - Yosuke Ichijima
- Division of Reproductive Sciences, Division of Developmental Biology, Perinatal Institute, Cincinnati Children's Hospital Medical Center, Cincinnati, OH 45229, USA; Department of Pediatrics, University of Cincinnati College of Medicine, Cincinnati, OH 49267, USA
| | - Fan Zhang
- Division of Experimental Hematology and Cancer Biology, Cincinnati Children's Hospital Medical Center, Cincinnati, OH 45229, USA; Department of Pediatrics, University of Cincinnati College of Medicine, Cincinnati, OH 49267, USA
| | - W Clark Bacon
- Division of Allergy and Immunology, Division of Human Genetics, Cincinnati Children's Hospital Medical Center, Cincinnati, OH 45229, USA; Department of Pediatrics, University of Cincinnati College of Medicine, Cincinnati, OH 49267, USA
| | - Kenneth D Greis
- Department of Cancer Biology, University of Cincinnati College of Medicine, Cincinnati, OH 49267, USA
| | - Paul R Andreassen
- Division of Experimental Hematology and Cancer Biology, Cincinnati Children's Hospital Medical Center, Cincinnati, OH 45229, USA; Department of Pediatrics, University of Cincinnati College of Medicine, Cincinnati, OH 49267, USA
| | - Artem Barski
- Division of Allergy and Immunology, Division of Human Genetics, Cincinnati Children's Hospital Medical Center, Cincinnati, OH 45229, USA; Department of Pediatrics, University of Cincinnati College of Medicine, Cincinnati, OH 49267, USA
| | - Satoshi H Namekawa
- Division of Reproductive Sciences, Division of Developmental Biology, Perinatal Institute, Cincinnati Children's Hospital Medical Center, Cincinnati, OH 45229, USA; Department of Pediatrics, University of Cincinnati College of Medicine, Cincinnati, OH 49267, USA.
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Composition, structure and mechanical properties define performance of pulmonary surfactant membranes and films. Chem Phys Lipids 2014; 185:153-75. [PMID: 25260665 DOI: 10.1016/j.chemphyslip.2014.09.002] [Citation(s) in RCA: 183] [Impact Index Per Article: 18.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2014] [Revised: 09/06/2014] [Accepted: 09/11/2014] [Indexed: 12/30/2022]
Abstract
The respiratory surface in the mammalian lung is stabilized by pulmonary surfactant, a membrane-based system composed of multiple lipids and specific proteins, the primary function of which is to minimize the surface tension at the alveolar air-liquid interface, optimizing the mechanics of breathing and avoiding alveolar collapse, especially at the end of expiration. The goal of the present review is to summarize current knowledge regarding the structure, lipid-protein interactions and mechanical features of surfactant membranes and films and how these properties correlate with surfactant biological function inside the lungs. Surfactant mechanical properties can be severely compromised by different agents, which lead to surfactant inhibition and ultimately contributes to the development of pulmonary disorders and pathologies in newborns, children and adults. A detailed comprehension of the unique mechanical and rheological properties of surfactant layers is crucial for the diagnostics and treatment of lung diseases, either by analyzing the contribution of surfactant impairment to the pathophysiology or by improving the formulations in surfactant replacement therapies. Finally, a short review is also included on the most relevant experimental techniques currently employed to evaluate lung surfactant mechanics, rheology, and inhibition and reactivation processes.
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35
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Fritz JM, Dong M, Apsley KS, Martin EP, Na CL, Sitaraman S, Weaver TE. Deficiency of the BiP cochaperone ERdj4 causes constitutive endoplasmic reticulum stress and metabolic defects. Mol Biol Cell 2013; 25:431-40. [PMID: 24336520 PMCID: PMC3923636 DOI: 10.1091/mbc.e13-06-0319] [Citation(s) in RCA: 45] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
The BiP cochaperone ERdj4 removes misfolded proteins from the ER lumen by associating with ERAD machinery. Global deficiency of ERdj4 results in widespread constitutive ER stress, decreased survival, and metabolic derangements in mice. These findings indicate that the chaperone activity of ERdj4 is important for ER homeostasis in vivo. Endoplasmic reticulum–localized DnaJ 4 (ERdj4) is an immunoglobulin-binding protein (BiP) cochaperone and component of the endoplasmic reticulum–associated degradation (ERAD) pathway that functions to remove unfolded/misfolded substrates from the ER lumen under conditions of ER stress. To elucidate the function of ERdj4 in vivo, we disrupted the ERdj4 locus using gene trap (GT) mutagenesis, leading to hypomorphic expression of ERdj4 in mice homozygous for the trapped allele (ERdj4GT/GT). Approximately half of ERdj4GT/GT mice died perinatally associated with fetal growth restriction, reduced hepatic glycogen stores, and hypoglycemia. Surviving adult mice exhibited evidence of constitutive ER stress in multiple cells/tissues, including fibroblasts, lung, kidney, salivary gland, and pancreas. Elevated ER stress in pancreatic β cells of ERdj4GT/GT mice was associated with β cell loss, hypoinsulinemia, and glucose intolerance. Collectively these results suggest an important role for ERdj4 in maintaining ER homeostasis during normal fetal growth and postnatal adaptation to metabolic stress.
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Affiliation(s)
- Jill M Fritz
- Perinatal Institute, Section of Neonatology, Perinatal and Pulmonary Biology, Cincinnati Children's Hospital Medical Center, and University of Cincinnati College of Medicine, Cincinnati, OH 45229
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Chapel A, Kieffer-Jaquinod S, Sagné C, Verdon Q, Ivaldi C, Mellal M, Thirion J, Jadot M, Bruley C, Garin J, Gasnier B, Journet A. An extended proteome map of the lysosomal membrane reveals novel potential transporters. Mol Cell Proteomics 2013; 12:1572-88. [PMID: 23436907 PMCID: PMC3675815 DOI: 10.1074/mcp.m112.021980] [Citation(s) in RCA: 143] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2012] [Revised: 02/01/2013] [Indexed: 12/22/2022] Open
Abstract
Lysosomes are membrane-bound endocytic organelles that play a major role in degrading cell macromolecules and recycling their building blocks. A comprehensive knowledge of the lysosome function requires an extensive description of its content, an issue partially addressed by previous proteomic analyses. However, the proteins underlying many lysosomal membrane functions, including numerous membrane transporters, remain unidentified. We performed a comparative, semi-quantitative proteomic analysis of rat liver lysosome-enriched and lysosome-nonenriched membranes and used spectral counts to evaluate the relative abundance of proteins. Among a total of 2,385 identified proteins, 734 proteins were significantly enriched in the lysosomal fraction, including 207 proteins already known or predicted as endo-lysosomal and 94 proteins without any known or predicted subcellular localization. The remaining 433 proteins had been previously assigned to other subcellular compartments but may in fact reside on lysosomes either predominantly or as a secondary location. Many membrane-associated complexes implicated in diverse processes such as degradation, membrane trafficking, lysosome biogenesis, lysosome acidification, signaling, and nutrient sensing were enriched in the lysosomal fraction. They were identified to an unprecedented extent as most, if not all, of their subunits were found and retained by our screen. Numerous transporters were also identified, including 46 novel potentially lysosomal proteins. We expressed 12 candidates in HeLa cells and observed that most of them colocalized with the lysosomal marker LAMP1, thus confirming their lysosomal residency. This list of candidate lysosomal proteins substantially increases our knowledge of the lysosomal membrane and provides a basis for further characterization of lysosomal functions.
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Affiliation(s)
- Agnès Chapel
- From the ‡Commissariat à l'Energie Atomique, Institut de Recherches en Technologies et Sciences du Vivant, Laboratoire Biologie à Grande Echelle, F-38054 Grenoble, France
- §INSERM, U1038, F-38054 Grenoble, France
- the ¶Université Joseph Fourier, Grenoble 1, F-38000, France
| | - Sylvie Kieffer-Jaquinod
- From the ‡Commissariat à l'Energie Atomique, Institut de Recherches en Technologies et Sciences du Vivant, Laboratoire Biologie à Grande Echelle, F-38054 Grenoble, France
- §INSERM, U1038, F-38054 Grenoble, France
- the ¶Université Joseph Fourier, Grenoble 1, F-38000, France
| | - Corinne Sagné
- the ‖Université Paris Descartes, Sorbonne Paris Cité, CNRS, UMR 8192, Centre Universitaire des Saints-Pères, 45 Rue des Saints-Pères, F-75006 Paris, France
| | - Quentin Verdon
- the ‖Université Paris Descartes, Sorbonne Paris Cité, CNRS, UMR 8192, Centre Universitaire des Saints-Pères, 45 Rue des Saints-Pères, F-75006 Paris, France
- §§Graduate School ED 419, Université Paris-Sud 11, Hôpital Bicêtre, F-94276 Le Kremlin Bicêtre France, and
| | - Corinne Ivaldi
- From the ‡Commissariat à l'Energie Atomique, Institut de Recherches en Technologies et Sciences du Vivant, Laboratoire Biologie à Grande Echelle, F-38054 Grenoble, France
- §INSERM, U1038, F-38054 Grenoble, France
- the ¶Université Joseph Fourier, Grenoble 1, F-38000, France
| | - Mourad Mellal
- From the ‡Commissariat à l'Energie Atomique, Institut de Recherches en Technologies et Sciences du Vivant, Laboratoire Biologie à Grande Echelle, F-38054 Grenoble, France
- §INSERM, U1038, F-38054 Grenoble, France
- the ¶Université Joseph Fourier, Grenoble 1, F-38000, France
| | - Jaqueline Thirion
- the **Unité de Recherche en Physiologie Moléculaire, Namur Research Institute for Life Sciences, University of Namur (FUNDP), 61, Rue de Bruxelles B,-5000, Namur, Belgium
| | - Michel Jadot
- the **Unité de Recherche en Physiologie Moléculaire, Namur Research Institute for Life Sciences, University of Namur (FUNDP), 61, Rue de Bruxelles B,-5000, Namur, Belgium
| | - Christophe Bruley
- From the ‡Commissariat à l'Energie Atomique, Institut de Recherches en Technologies et Sciences du Vivant, Laboratoire Biologie à Grande Echelle, F-38054 Grenoble, France
- §INSERM, U1038, F-38054 Grenoble, France
- the ¶Université Joseph Fourier, Grenoble 1, F-38000, France
| | - Jérôme Garin
- From the ‡Commissariat à l'Energie Atomique, Institut de Recherches en Technologies et Sciences du Vivant, Laboratoire Biologie à Grande Echelle, F-38054 Grenoble, France
- §INSERM, U1038, F-38054 Grenoble, France
- the ¶Université Joseph Fourier, Grenoble 1, F-38000, France
| | - Bruno Gasnier
- the ‖Université Paris Descartes, Sorbonne Paris Cité, CNRS, UMR 8192, Centre Universitaire des Saints-Pères, 45 Rue des Saints-Pères, F-75006 Paris, France
| | - Agnès Journet
- From the ‡Commissariat à l'Energie Atomique, Institut de Recherches en Technologies et Sciences du Vivant, Laboratoire Biologie à Grande Echelle, F-38054 Grenoble, France
- §INSERM, U1038, F-38054 Grenoble, France
- the ¶Université Joseph Fourier, Grenoble 1, F-38000, France
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Soma-Nagae T, Nada S, Kitagawa M, Takahashi Y, Mori S, Oneyama C, Okada M. The lysosomal signaling anchor p18/LAMTOR1 controls epidermal development by regulating lysosome-mediated catabolic processes. J Cell Sci 2013; 126:3575-84. [DOI: 10.1242/jcs.121913] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022] Open
Abstract
The lysosomal adaptor protein p18 is an essential anchor of a scaffolding complex for the mTORC1 and MAPK pathways, which play crucial roles in controlling cell growth and energy homeostasis. To elucidate the in vivo function of the p18-mediated pathway, we conditionally ablated p18 in the mouse epidermis. Mutant mice were born with severe defects in formation of the stratum corneum and died within 12 h after birth due to dehydration caused by loss of skin barrier function. Mutant epidermal cells can grow and differentiate into granular cells, but exhibit functional defects in corneocyte maturation. Electron microscopy identified abnormal immature cells, overlying the mutant granular cells, which accumulated autophagosomes, glycogen granules and dead nuclei. Cell culture analysis showed that loss of p18 attenuated lysosome function, resulting in accumulation of immature lysosomes and autophagosomes. Analyses of lysosome behavior revealed that p18 is required for functional interaction between lysosomes and target organelles including autophagosomes. These findings suggest that p18-mediated pathways control lysosome-mediated catabolic processes crucial role for development of mouse epidermis.
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38
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Bacillus anthracis lethal toxin reduces human alveolar epithelial barrier function. Infect Immun 2012; 80:4374-87. [PMID: 23027535 DOI: 10.1128/iai.01011-12] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022] Open
Abstract
The lung is the site of entry for Bacillus anthracis in inhalation anthrax, the deadliest form of the disease. Bacillus anthracis produces virulence toxins required for disease. Alveolar macrophages were considered the primary target of the Bacillus anthracis virulence factor lethal toxin because lethal toxin inhibits mouse macrophages through cleavage of MEK signaling pathway components, but we have reported that human alveolar macrophages are not a target of lethal toxin. Our current results suggest that, unlike human alveolar macrophages, the cells lining the respiratory units of the lung, alveolar epithelial cells, are a target of lethal toxin in humans. Alveolar epithelial cells expressed lethal toxin receptor protein, bound the protective antigen component of lethal toxin, and were subject to lethal-toxin-induced cleavage of multiple MEKs. These findings suggest that human alveolar epithelial cells are a target of Bacillus anthracis lethal toxin. Further, no reduction in alveolar epithelial cell viability was observed, but lethal toxin caused actin rearrangement and impaired desmosome formation, consistent with impaired barrier function as well as reduced surfactant production. Therefore, by compromising epithelial barrier function, lethal toxin may play a role in the pathogenesis of inhalation anthrax by facilitating the dissemination of Bacillus anthracis from the lung in early disease and promoting edema in late stages of the illness.
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Agassandian M, Mallampalli RK. Surfactant phospholipid metabolism. Biochim Biophys Acta Mol Cell Biol Lipids 2012; 1831:612-25. [PMID: 23026158 DOI: 10.1016/j.bbalip.2012.09.010] [Citation(s) in RCA: 153] [Impact Index Per Article: 12.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2012] [Revised: 09/07/2012] [Accepted: 09/16/2012] [Indexed: 12/16/2022]
Abstract
Pulmonary surfactant is essential for life and is composed of a complex lipoprotein-like mixture that lines the inner surface of the lung to prevent alveolar collapse at the end of expiration. The molecular composition of surfactant depends on highly integrated and regulated processes involving its biosynthesis, remodeling, degradation, and intracellular trafficking. Despite its multicomponent composition, the study of surfactant phospholipid metabolism has focused on two predominant components, disaturated phosphatidylcholine that confers surface-tension lowering activities, and phosphatidylglycerol, recently implicated in innate immune defense. Future studies providing a better understanding of the molecular control and physiological relevance of minor surfactant lipid components are needed. This article is part of a Special Issue entitled Phospholipids and Phospholipid Metabolism.
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Affiliation(s)
- Marianna Agassandian
- Department of Medicine, Acute Lung Injury Center of Excellence, the University of Pittsburgh, Pittsburgh, PA 15213, USA
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40
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Roszell BR, Tao JQ, Yu KJ, Huang S, Bates SR. Characterization of the Niemann-Pick C pathway in alveolar type II cells and lamellar bodies of the lung. Am J Physiol Lung Cell Mol Physiol 2012; 302:L919-32. [PMID: 22367786 DOI: 10.1152/ajplung.00383.2011] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
The Niemann-Pick C (NPC) pathway plays an essential role in the intracellular trafficking of cholesterol by facilitating the release of lipoprotein-derived sterol from the lumen of lysosomes. Regulation of cellular cholesterol homeostasis is of particular importance to lung alveolar type II cells because of the need for production of surfactant with an appropriate lipid composition. We performed microscopic and biochemical analysis of NPC proteins in isolated rat type II pneumocytes. NPC1 and NPC2 proteins were present in the lung, isolated type II cells in culture, and alveolar macrophages. The glycosylated and nonglycosylated forms of NPC1 were prominent in the lung and the lamellar body organelles. Immunocytochemical analysis of isolated type II pneumocytes showed localization of NPC1 to the limiting membrane of lamellar bodies. NPC2 and lysosomal acid lipase were found within these organelles, as confirmed by z-stack analysis of confocal images. All three proteins also were identified in small, lysosome-like vesicles. In the presence of serum, pharmacological inhibition of the NPC pathway with compound U18666A resulted in doubling of the cholesterol content of the type II cells. Filipin staining revealed a striking accumulation of cholesterol within lamellar bodies. Thus the NPC pathway functions to control cholesterol accumulation in lamellar bodies of type II pneumocytes and, thereby, may play a role in the regulation of surfactant cholesterol content.
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Affiliation(s)
- Blair R Roszell
- Institute for Environmental Medicine, Univ. of Pennsylvania, Philadelphia, PA 19104-6068, USA
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Flamein F, Riffault L, Muselet-Charlier C, Pernelle J, Feldmann D, Jonard L, Durand-Schneider AM, Coulomb A, Maurice M, Nogee LM, Inagaki N, Amselem S, Dubus JC, Rigourd V, Brémont F, Marguet C, Brouard J, de Blic J, Clement A, Epaud R, Guillot L. Molecular and cellular characteristics of ABCA3 mutations associated with diffuse parenchymal lung diseases in children. Hum Mol Genet 2011; 21:765-75. [PMID: 22068586 DOI: 10.1093/hmg/ddr508] [Citation(s) in RCA: 71] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
ABCA3 (ATP-binding cassette subfamily A, member 3) is expressed in the lamellar bodies of alveolar type II cells and is crucial to pulmonary surfactant storage and homeostasis. ABCA3 gene mutations have been associated with neonatal respiratory distress (NRD) and pediatric interstitial lung disease (ILD). The objective of this study was to look for ABCA3 gene mutations in patients with severe NRD and/or ILD. The 30 ABCA3 coding exons were screened in 47 patients with severe NRD and/or ILD. ABCA3 mutations were identified in 10 out of 47 patients, including 2 homozygous, 5 compound heterozygous and 3 heterozygous patients. SP-B and SP-C expression patterns varied across patients. Among patients with ABCA3 mutations, five died shortly after birth and five developed ILD (including one without NRD). Functional studies of p.D253H and p.T1173R mutations revealed that p.D253H and p.T1173R induced abnormal lamellar bodies. Additionally, p.T1173R increased IL-8 secretion in vitro. In conclusion, we identified new ABCA3 mutations in patients with life-threatening NRD and/or ILD. Two mutations associated with ILD acted via different pathophysiological mechanisms despite similar clinical phenotypes.
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42
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Chapin C, Bailey NA, Gonzales LW, Lee JW, Gonzalez RF, Ballard PL. Distribution and surfactant association of carcinoembryonic cell adhesion molecule 6 in human lung. Am J Physiol Lung Cell Mol Physiol 2011; 302:L216-25. [PMID: 22037359 DOI: 10.1152/ajplung.00055.2011] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Carcinoembryonic cell adhesion molecule 6 (CEACAM6) is a glycosylated, glycophosphatidylinositol-anchored protein expressed in epithelial cells of various primate tissues. It binds gram-negative bacteria and is overexpressed in human cancers. CEACAM6 is associated with lamellar bodies of cultured type II cells of human fetal lung and protects surfactant function in vitro. In this study, we characterized CEACAM6 expression in vivo in human lung. CEACAM6 was present in lung lavage of premature infants at birth and increased progressively in intubated infants with lung disease. Of surfactant-associated CEACAM6, ∼80% was the fully glycosylated, 90-kDa form that contains the glycophosphatidylinositol anchor, and the concentration (3.9% of phospholipid for adult lung) was comparable to that for surfactant proteins (SP)-A/B/C. We examined the affinity of CEACAM6 by purification of surfactant on density gradient centrifugation; concentrations of CEACAM6 and SP-B per phospholipid were unchanged, whereas levels of total protein and SP-A decreased by 60%. CEACAM6 mRNA content decreased progressively from upper trachea to peripheral fetal lung, whereas protein levels were similar in all regions of adult lung, suggesting proximal-to-distal developmental expression in lung epithelium. In adult lung, most type I cells and ∼50% of type II cells were immunopositive. We conclude that CEACAM6 is expressed by alveolar and airway epithelial cells of human lung and is secreted into lung-lining fluid, where fully glycosylated protein binds to surfactant. Production appears to be upregulated during neonatal lung disease, perhaps related to roles of CEACAM6 in surfactant function, cell proliferation, and innate immune defense.
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Affiliation(s)
- Cheryl Chapin
- Department of Pediatrics, University of California San Francisco, San Francisco, California, USA
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43
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Mayhew TM. Mapping the distributions and quantifying the labelling intensities of cell compartments by immunoelectron microscopy: progress towards a coherent set of methods. J Anat 2011; 219:647-60. [PMID: 21999926 DOI: 10.1111/j.1469-7580.2011.01438.x] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023] Open
Abstract
An important tool in cell biology is the combination of immunogold labelling and transmission electron microscopy (TEM) by which target molecules (e.g. antigens) are bound specifically to affinity markers (primary antibodies) and then detected and localised with visualisation probes (e.g. colloidal gold particles bound to protein A). Gold particles are electron-dense, punctate and available in different sizes whilst TEM provides high-resolution images of particles and cell compartments. By virtue of these properties, the combination can be used also to quantify one or more defined targets in cell compartments. During the past decade, new ways of quantifying gold labelling within cells have been devised. Their efficiency and validity rely on sound principles of specimen sampling, event counting and inferential statistics. These include random selection of items at each sampling stage (e.g. specimen blocks, thin sections, microscopical fields), stereological analysis of cell ultrastructure, unbiased particle counting and statistical evaluation of a suitable null hypothesis (no difference in the intensity or pattern of labelling between compartments or groups of cells). The following approaches are possible: (i) A target molecule can be tested for preferential labelling by mapping the localisation of gold particles across a set of compartments. (ii) Data from wild-type and knockdown/knockout control cells can be used to correct raw gold particle counts, estimate specific labelling densities and then test for preferential labeling. (iii) The same antigen can be mapped in two or more groups of cells to test whether there are experimental shifts in compartment labelling patterns. (iv) A variant of this approach uses more than one size of gold particle to test whether or not different antigens colocalise in one or more compartments. (v) In studies involving antigen translocation, absolute numbers of gold particles can be mapped over compartments at specific positions within polarised, oriented or dividing cells. Here, the current state of the art is reviewed and approaches are illustrated with virtual datasets.
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Affiliation(s)
- Terry M Mayhew
- School of Biomedical Sciences, Queen's Medical Centre, University of Nottingham, Nottingham, UK.
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