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Aribindi K, Lim M, Lakshminrusimha S, Albertson T. Investigational pharmacological agents for the treatment of ARDS. Expert Opin Investig Drugs 2024; 33:243-277. [PMID: 38316432 DOI: 10.1080/13543784.2024.2315128] [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: 10/31/2023] [Accepted: 01/25/2024] [Indexed: 02/07/2024]
Abstract
INTRODUCTION Acute Respiratory Distress Syndrome (ARDS) is a heterogeneous form of lung injury with severe hypoxemia and bilateral infiltrates after an inciting event that results in diffuse lung inflammation with a high mortality rate. While research in COVID-related ARDS has resulted in several pharmacotherapeutic agents that have undergone successful investigation, non-COVID ARDS studies have not resulted in many widely accepted pharmacotherapeutic agents despite exhaustive research. AREAS COVERED The aim of this review is to discuss adjuvant pharmacotherapies targeting non-COVID Acute Lung Injury (ALI)/ARDS and novel therapeutics in COVID associated ALI/ARDS. In ARDS, variable data may support selective use of neuromuscular blocking agents, corticosteroids and neutrophil elastase inhibitors, but are not yet universally used. COVID-ALI/ARDS has data supporting the use of IL-6 monoclonal antibodies, corticosteroids, and JAK inhibitor therapy. EXPERT OPINION Although ALI/ARDS modifying pharmacological agents have been identified in COVID-related disease, the data in non-COVID ALI/ARDS has been less compelling. The increased use of more specific molecular phenotyping based on physiologic parameters and biomarkers, will ensure equipoise between groups, and will likely allow more precision in confirming pharmacological agent efficacy in future studies.
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Affiliation(s)
- Katyayini Aribindi
- Department of Internal Medicine, Division of Pulmonary, Critical Care & Sleep Medicine, U.C. Davis School of Medicine, Sacramento, CA, USA
- Department of Medicine, Veterans Affairs North California Health Care System, Mather, CA, USA
| | - Michelle Lim
- Department of Pediatrics, Division of Pediatric Critical Care Medicine, U.C. Davis School of Medicine, Sacramento, CA, USA
| | - Satyan Lakshminrusimha
- Department of Pediatrics, Division of Neonatal-Perinatal Medicine, U.C. Davis School of Medicine, Sacramento, CA, USA
| | - Timothy Albertson
- Department of Internal Medicine, Division of Pulmonary, Critical Care & Sleep Medicine, U.C. Davis School of Medicine, Sacramento, CA, USA
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Fouedji C, Etémé AS, Tabi CB, Fouda HPE, Kofané TC. Multisolitons-like patterns in a one-dimensional MARCKS protein cyclic model. J Theor Biol 2024; 579:111702. [PMID: 38096977 DOI: 10.1016/j.jtbi.2023.111702] [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: 07/30/2023] [Revised: 11/16/2023] [Accepted: 12/08/2023] [Indexed: 12/24/2023]
Abstract
In this paper, we study the nonlinear dynamics of the MARCKS protein between cytosol and cytoplasmic membrane through the modulational instability phenomenon. The reaction-diffusion generic model used here is firstly transformed into a cubic complex Ginzburg-Landau equation. Then, modulational instability (MI) is carried out in order to derive the MI criteria. We find the domains of some parameter space where nonlinear patterns are expected in the model. The analytical results on the MI growth rate predict that phosphorylation and binding rates affect MARCKS dynamics in opposite way: while the phosphorylation rate tends to support highly localized structures of MARCKS, the binding rate in turn tends to slow down such features. On the other hand, self-diffusion process always amplifies the MI phenomenon. These predictions are confirmed by numerical simulations. As a result, the cyclic transport of MARCKS protein from membrane to cytosol may be done by means of multisolitons-like patterns.
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Affiliation(s)
- Chenceline Fouedji
- Laboratory of Biophysics, Department of Physics, Faculty of Science, University of Yaounde I, P.O. Box 812, Yaounde, Cameroon.
| | - Armand Sylvin Etémé
- Laboratory of Biophysics, Department of Physics, Faculty of Science, University of Yaounde I, P.O. Box 812, Yaounde, Cameroon.
| | - Conrad Bertrand Tabi
- Botswana International University of Science and Technology, P/Bag 16 Palapye, Botswana.
| | - Henri Paul Ekobena Fouda
- Laboratory of Biophysics, Department of Physics, Faculty of Science, University of Yaounde I, P.O. Box 812, Yaounde, Cameroon.
| | - Timoléon Crépin Kofané
- Laboratory of Mechanics, Department of Physics, Faculty of Science, University of Yaounde I, P.O. Box 812, Yaounde, Cameroon.
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Conley HE, Brown CF, Westerman TL, Elfenbein JR, Sheats MK. MARCKS Inhibition Alters Bovine Neutrophil Responses to Salmonella Typhimurium. Biomedicines 2024; 12:442. [PMID: 38398044 PMCID: PMC10886653 DOI: 10.3390/biomedicines12020442] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2024] [Revised: 02/08/2024] [Accepted: 02/12/2024] [Indexed: 02/25/2024] Open
Abstract
Neutrophils are innate immune cells that respond quickly to sites of bacterial infection and play an essential role in host defense. Interestingly, some bacterial pathogens benefit from exuberant neutrophil inflammation. Salmonella is one such pathogen that can utilize the toxic mediators released by neutrophils to colonize the intestine and cause enterocolitis. Because neutrophils can aid gut colonization during Salmonella infection, neutrophils represent a potential host-directed therapeutic target. Myristoylated alanine-rich C-kinase substrate (MARCKS) is an actin-binding protein that plays an essential role in many neutrophil effector responses. We hypothesized that inhibition of MARCKS protein would alter bovine neutrophil responses to Salmonella Typhimurium (STm) ex vivo. We used a MARCKS inhibitor peptide to investigate the role of MARCKS in neutrophil responses to STm. This study demonstrates that MARCKS inhibition attenuated STm-induced neutrophil adhesion and chemotaxis. Interestingly, MARCKS inhibition also enhanced neutrophil phagocytosis and respiratory burst in response to STm. This is the first report describing the role of MARCKS protein in neutrophil antibacterial responses.
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Affiliation(s)
- Haleigh E Conley
- Department of Clinical Sciences, College of Veterinary Medicine, North Carolina State University, Raleigh, NC 27607, USA
- Comparative Medicine Institute, North Carolina State University, Raleigh, NC 27607, USA
| | - Chalise F Brown
- Department of Clinical Sciences, College of Veterinary Medicine, North Carolina State University, Raleigh, NC 27607, USA
| | - Trina L Westerman
- Department of Pathobiological Sciences, School of Veterinary Medicine, University of Wisconsin-Madison, Madison, WI 53706, USA
| | - Johanna R Elfenbein
- Department of Pathobiological Sciences, School of Veterinary Medicine, University of Wisconsin-Madison, Madison, WI 53706, USA
| | - M Katie Sheats
- Department of Clinical Sciences, College of Veterinary Medicine, North Carolina State University, Raleigh, NC 27607, USA
- Comparative Medicine Institute, North Carolina State University, Raleigh, NC 27607, USA
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Gui Z, Hu W, Kong Q, Liu C, Xu Y, Wang F. Esophageal stenosis as an independent factor of poor prognosis in patients with ESCC treated with definitive chemoradiotherapy. Future Oncol 2022; 18:4193-4207. [PMID: 36651337 DOI: 10.2217/fon-2022-0125] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023] Open
Abstract
Aim: To evaluate the clinical outcome and elucidate the prognostic factors in patients with esophageal squamous cell carcinoma (ESCC) treated with definitive chemoradiotherapy (CRT). Patients: Data for patients newly diagnosed with ESCC receiving definitive CRT at our institution between 2012 and 2018 were retrospectively reviewed. Results: A total of 201 patients were included. Severe stenosis after radiotherapy was an independent factor relevant to prognosis. Maximal esophageal wall thickness, short-term responses, severe stenosis at diagnosis and a high neutrophil-to-lymphocyte ratio were independent risk factors for the occurrence of severe stenosis after radiotherapy. Conclusion: Severe stenosis after radiotherapy is a useful predictive indicator in patients with ESCC receiving definitive CRT. Further studies are needed to verify these findings.
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Affiliation(s)
- Zhongxuan Gui
- Department of Radiation Oncology, The First Affiliated Hospital of Anhui Medical University, Hefei, Anhui, 230022, People's Republic of China
| | - Wenjun Hu
- Department of Radiation Oncology, Anhui Chest Hospital, Hefei, Anhui, 230022, People's Republic of China
| | - Qi Kong
- Department of Radiation Oncology, Anhui Second People's Hospital, Hefei, Anhui, 230012, People's Republic of China
| | - Can Liu
- Department of Cardiothoracic Surgery, The First Affiliated Hospital of Anhui Medical University, Hefei, Anhui, 230022, People's Republic of China
| | - Yuechen Xu
- Department of Radiation Oncology, The First Affiliated Hospital of Anhui Medical University, Hefei, Anhui, 230022, People's Republic of China
| | - Fan Wang
- Department of Radiation Oncology, The First Affiliated Hospital of Anhui Medical University, Hefei, Anhui, 230022, People's Republic of China
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Chen Z, Zhang W, Selmi C, Ridgway WM, Leung PS, Zhang F, Gershwin ME. The myristoylated alanine-rich C-kinase substrates (MARCKS): A membrane-anchored mediator of the cell function. Autoimmun Rev 2021; 20:102942. [PMID: 34509657 PMCID: PMC9746065 DOI: 10.1016/j.autrev.2021.102942] [Citation(s) in RCA: 22] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2021] [Accepted: 06/26/2021] [Indexed: 12/15/2022]
Abstract
The myristoylated alanine-rich C-kinase substrate (MARCKS) and the MARCKS-related protein (MARCKSL1) are ubiquitous, highly conserved membrane-associated proteins involved in the structural modulation of the actin cytoskeleton, chemotaxis, motility, cell adhesion, phagocytosis, and exocytosis. MARCKS includes an N-terminal myristoylated domain for membrane binding, a highly conserved MARCKS Homology 2 (MH2) domain, and an effector domain (which is the phosphorylation site). MARCKS can sequester phosphatidylinositol-4, 5-diphosphate (PIP2) at lipid rafts in the plasma membrane of quiescent cells, an action reversed by protein kinase C (PKC), ultimately modulating the immune function. Being expressed mostly in innate immune cells, MARCKS promotes the inflammation-driven migration and adhesion of cells and the secretion of cytokines such as tumor necrosis factor (TNF). From a clinical point of view, MARCKS is overexpressed in patients with schizophrenia and bipolar disorders, while the brain level of MARCKS phosphorylation is associated with Alzheimer's disease. Furthermore, MARCKS is associated with the development and progression of numerous types of cancers. Data in autoimmune diseases are limited to rheumatoid arthritis models in which a connection between MARCKS and the JAK-STAT pathway is mediated by miRNAs. We provide a comprehensive overview of the structure of MARCKS, its molecular characteristics and functions from a biological and pathogenetic standpoint, and will discuss the clinical implications of this pathway.
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Affiliation(s)
- Zhilei Chen
- Division of Rheumatology, Allergy, and Clinical Immunology, University of California Davis, Davis, CA 95616, United States,Department of Rheumatology and Clinical Immunology, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing 100730, China
| | - Weici Zhang
- Division of Rheumatology, Allergy, and Clinical Immunology, University of California Davis, Davis, CA 95616, United States,Corresponding authors. (W. Zhang), (F. Zhang)
| | - Carlo Selmi
- Humanitas Research Hospital - IRCCS, Rozzano, Milan, Italy
| | - William M. Ridgway
- Division of Rheumatology, Allergy, and Clinical Immunology, University of California Davis, Davis, CA 95616, United States
| | - Patrick S.C. Leung
- Division of Rheumatology, Allergy, and Clinical Immunology, University of California Davis, Davis, CA 95616, United States
| | - Fengchun Zhang
- Department of Rheumatology and Clinical Immunology, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing 100730, China,Corresponding authors. (W. Zhang), (F. Zhang)
| | - M. Eric Gershwin
- Division of Rheumatology, Allergy, and Clinical Immunology, University of California Davis, Davis, CA 95616, United States
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Iyer DN, Faruq O, Zhang L, Rastgoo N, Liu A, Chang H. Pathophysiological roles of myristoylated alanine-rich C-kinase substrate (MARCKS) in hematological malignancies. Biomark Res 2021; 9:34. [PMID: 33958003 PMCID: PMC8101130 DOI: 10.1186/s40364-021-00286-9] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2021] [Accepted: 04/16/2021] [Indexed: 12/17/2022] Open
Abstract
The myristoylated alanine-rich C-kinase substrate (MARCKS) protein has been at the crossroads of multiple signaling pathways that govern several critical operations in normal and malignant cellular physiology. Functioning as a target of protein kinase C, MARCKS shuttles between the phosphorylated cytosolic form and the unphosphorylated plasma membrane-bound states whilst regulating several molecular partners including, but not limited to calmodulin, actin, phosphatidylinositol-4,5-bisphosphate, and phosphoinositide-3-kinase. As a result of these interactions, MARCKS directly or indirectly modulates a host of cellular functions, primarily including cytoskeletal reorganization, membrane trafficking, cell secretion, inflammatory response, cell migration, and mitosis. Recent evidence indicates that dysregulated expression of MARCKS is associated with the development and progression of hematological cancers. While it is understood that MARCKS impacts the overall carcinogenesis as well as plays a part in determining the disease outcome in blood cancers, we are still at an early stage of interpreting the pathophysiological roles of MARCKS in neoplastic disease. The situation is further complicated by contradictory reports regarding the role of phosphorylated versus an unphosphorylated form of MARCKS as an oncogene versus tumor suppressor in blood cancers. In this review, we will investigate the current body of knowledge and evolving concepts of the physical properties, molecular network, functional attributes, and the likely pathogenic roles of MARCKS in hematological malignancies. Key emphasis will also be laid upon understanding the novel mechanisms by which MARCKS determines the overall disease prognosis by playing a vital role in the induction of therapeutic resistance. Additionally, we will highlight the importance of MARCKS as a valuable therapeutic target in blood cancers and will discuss the potential of existing strategies available to tackle MARCKS-driven blood cancers.
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Affiliation(s)
- Deepak Narayanan Iyer
- Laboratory medicine program, Toronto General Hospital, University Health Network, University of Toronto, Toronto, Canada
| | - Omar Faruq
- Laboratory medicine program, Toronto General Hospital, University Health Network, University of Toronto, Toronto, Canada
| | - Lun Zhang
- Laboratory medicine program, Toronto General Hospital, University Health Network, University of Toronto, Toronto, Canada
| | - Nasrin Rastgoo
- Laboratory medicine program, Toronto General Hospital, University Health Network, University of Toronto, Toronto, Canada
| | - Aijun Liu
- Department of Hematology, Beijing Chaoyang Hospital, Capital University, Beijing, China.
| | - Hong Chang
- Laboratory medicine program, Toronto General Hospital, University Health Network, University of Toronto, Toronto, Canada.
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Iqbal S, Walsh TR, Rodger A, Packer NH. Interaction between Polysialic Acid and the MARCKS-ED Peptide at the Molecular Level. ACS Chem Neurosci 2020; 11:1944-1954. [PMID: 32412743 DOI: 10.1021/acschemneuro.0c00139] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
Abstract
Polysialic acid (polySia) is a highly negatively charged linear homopolymer comprising α-2,8-linked sialic acids. It is abundant in the embryonic brain and modulates various functions such as differentiation and synaptic plasticity in the adult central nervous system by direct binding to its protein partners. One such example is the binding of polySia to myristoylated-alanine rich C-kinase substrate (MARCKS) to modulate neuritogenesis. To understand their interaction mechanism at the molecular level, we performed a binding assay which showed a direct binding of the MARCKS-ED peptide (KKKKKRFSFKKSFKLSGFSFKKNKK) with polySia in a concentration-dependent manner. Molecular dynamics simulations revealed that this binding is not exclusively dominated by electrostatics but can in part be attributed to the presence of near-regularly spaced Phe residues, that confer a compact 3D conformation based on pseudoglycine loop structures supported by Phe-Phe interactions. Our simulations, which are confirmed by circular dichroism measurements, also indicate that the peptide-polySia binding induces large-scale conformational rearrangement of polySia into coils at the binding site, whereas the peptide conformation is relatively unperturbed. As a consequence, we predict that each peptide can bind to a domain extending ∼14 polySia repeat units. Using the fluorescently tagged MARCKS-ED peptide on rat brainstem tissue sections, we demonstrate the ability of the peptide to detect polySia, similarly to polySia-specific antibody mAb735, especially in the spinal trigeminal nucleus and the dorsal vagal complex. This study provides information about the interaction between polySia and its CNS protein binding partner, MARCKS, and provides a fundamental platform for further studies to explore the prospect of the MARCKS-ED as an effective polySia-binding peptide for bioimaging and drug delivery applications.
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Affiliation(s)
- Sameera Iqbal
- Department of Molecular Sciences, Macquarie University, Sydney, New South Wales 2109, Australia
- ARC Centre of Excellence for Nanoscale Biophotonics, Macquarie University, Sydney, New South Wales 2109, Australia
| | - Tiffany R. Walsh
- Institute for Frontier Materials, Deakin University, Geelong, Victoria 3216, Australia
| | - Alison Rodger
- Department of Molecular Sciences, Macquarie University, Sydney, New South Wales 2109, Australia
| | - Nicolle H. Packer
- Department of Molecular Sciences, Macquarie University, Sydney, New South Wales 2109, Australia
- ARC Centre of Excellence for Nanoscale Biophotonics, Macquarie University, Sydney, New South Wales 2109, Australia
- Institute for Glycomics, Griffith University, Gold Coast, Queensland 4222, Australia
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8
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Sheats MK, Yin Q, Fang S, Park J, Crews AL, Parikh I, Dickson B, Adler KB. MARCKS and Lung Disease. Am J Respir Cell Mol Biol 2019; 60:16-27. [PMID: 30339463 DOI: 10.1165/rcmb.2018-0285tr] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
MARCKS (myristoylated alanine-rich C kinase substrate) is a prominent PKC substrate expressed in all eukaryotic cells. It is known to bind to and cross-link actin filaments, to serve as a bridge between Ca2+/calmodulin and PKC signaling, and to sequester the signaling molecule phosphatidylinositol 4,5-bisphosphate in the plasma membrane. Since the mid-1980s, this evolutionarily conserved and ubiquitously expressed protein has been associated with regulating cellular events that require dynamic actin reorganization, including cellular adhesion, migration, and exocytosis. More recently, translational studies have implicated MARCKS in the pathophysiology of a number of airway diseases, including chronic obstructive pulmonary disease, asthma, lung cancer, and acute lung injury/acute respiratory distress syndrome. This article summarizes the structure and cellular function of MARCKS (also including MARCKS family proteins and MARCKSL1 [MARCKS-like protein 1]). Evidence for MARCKS's role in several lung diseases is discussed, as are the technological innovations that took MARCKS-targeting strategies from theoretical to therapeutic. Descriptions and updates derived from ongoing clinical trials that are investigating inhalation of a MARCKS-targeting peptide as therapy for patients with chronic bronchitis, lung cancer, and ARDS are provided.
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Affiliation(s)
| | - Qi Yin
- 2 Department of Molecular Biomedical Sciences, North Carolina State University College of Veterinary Medicine, Raleigh, North Carolina; and
| | - Shijing Fang
- 2 Department of Molecular Biomedical Sciences, North Carolina State University College of Veterinary Medicine, Raleigh, North Carolina; and
| | - Joungjoa Park
- 2 Department of Molecular Biomedical Sciences, North Carolina State University College of Veterinary Medicine, Raleigh, North Carolina; and
| | - Anne L Crews
- 2 Department of Molecular Biomedical Sciences, North Carolina State University College of Veterinary Medicine, Raleigh, North Carolina; and
| | - Indu Parikh
- 3 BioMarck Pharmaceuticals, Durham, North Carolina
| | | | - Kenneth B Adler
- 2 Department of Molecular Biomedical Sciences, North Carolina State University College of Veterinary Medicine, Raleigh, North Carolina; and
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Marinho MC, Pacheco ABF, Costa GCV, Ortiz ND, Zajdenverg L, Sansone C. Quantitative gingival crevicular fluid proteome in type 2 diabetes mellitus and chronic periodontitis. Oral Dis 2018; 25:588-595. [PMID: 30362201 DOI: 10.1111/odi.12996] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2018] [Revised: 10/01/2018] [Accepted: 10/16/2018] [Indexed: 12/12/2022]
Abstract
OBJECTIVE The aim of this study was to investigate the proteome of the gingival crevicular fluid comparing the relative abundance of proteins from type 2 diabetes mellitus (2DM) individuals and chronic periodontitis (CP) affected sites, subjects affected by both conditions and healthy individuals. MATERIAL AND METHODS Twenty individuals were equally allocated in four groups, 2DM with CP, 2DM periodontally healthy, CP without 2DM, and periodontally healthy without 2DM. The relative quantification of proteins was accessed with iTRAQ labeling and mass spectrometry. RESULTS AND CONCLUSION A total of 104 proteins showed significant differences in abundance in pairwise comparisons. Some presented different levels in all diseased groups as compared to control, either increasing (rap guanine nucleotide exchange factor, S100A8, S100A9, and immunoglobulins) or decreasing (actins, myristoylated alanine-rich C-kinase substrate, and glutathione S-transferase). Other differences were specific for a given condition: Titin, neutrophil elastase, and myeloperoxidase levels were higher in the DP group, cathelicidin antimicrobial peptide decreased in CP, and annexin decreased in DH. These differences in the proteome can provide clues for further studies that will validate the variation in their levels and their role in both diseases.
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Affiliation(s)
- Marcelo C Marinho
- Department of Dental Clinic, Division of Periodontology, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil
| | - Ana Beatriz F Pacheco
- Institute of Biophysics Carlos Chagas Filho, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil
| | - Giovani C V Costa
- Brazilian Doping Control Laboratory (LBCD/LADETEC/IQ), Federal University of Rio de Janeiro, Rio de Janeiro, Brazil
| | - Nina D Ortiz
- Brazilian Doping Control Laboratory (LBCD/LADETEC/IQ), Federal University of Rio de Janeiro, Rio de Janeiro, Brazil
| | - Lenita Zajdenverg
- Department of Internal Medicine, Section of Diabetes and Nutrology, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil
| | - Carmelo Sansone
- Department of Dental Clinic, Division of Periodontology, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil
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El Amri M, Fitzgerald U, Schlosser G. MARCKS and MARCKS-like proteins in development and regeneration. J Biomed Sci 2018; 25:43. [PMID: 29788979 PMCID: PMC5964646 DOI: 10.1186/s12929-018-0445-1] [Citation(s) in RCA: 59] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2018] [Accepted: 05/07/2018] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND The Myristoylated Alanine-Rich C-kinase Substrate (MARCKS) and MARCKS-like protein 1 (MARCKSL1) have a wide range of functions, ranging from roles in embryonic development to adult brain plasticity and the inflammatory response. Recently, both proteins have also been identified as important players in regeneration. Upon phosphorylation by protein kinase C (PKC) or calcium-dependent calmodulin-binding, MARCKS and MARCKSL1 translocate from the membrane into the cytosol, modulating cytoskeletal actin dynamics and vesicular trafficking and activating various signal transduction pathways. As a consequence, the two proteins are involved in the regulation of cell migration, secretion, proliferation and differentiation in many different tissues. MAIN BODY Throughout vertebrate development, MARCKS and MARCKSL1 are widely expressed in tissues derived from all germ layers, with particularly strong expression in the nervous system. They have been implicated in the regulation of gastrulation, myogenesis, brain development, and other developmental processes. Mice carrying loss of function mutations in either Marcks or Marcksl1 genes die shortly after birth due to multiple deficiencies including detrimental neural tube closure defects. In adult vertebrates, MARCKS and MARCKL1 continue to be important for multiple regenerative processes including peripheral nerve, appendage, and tail regeneration, making them promising targets for regenerative medicine. CONCLUSION This review briefly summarizes the molecular interactions and cellular functions of MARCKS and MARCKSL1 proteins and outlines their vital roles in development and regeneration.
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Affiliation(s)
- Mohamed El Amri
- Centre for Research in Medical Devices (CÚRAM), National University of Ireland, Galway, Biomedical Sciences Building, Newcastle Road, Galway, Ireland
| | - Una Fitzgerald
- Galway Neuroscience Centre, School of Natural Sciences, Biomedical Sciences Building, National University of Ireland, Newcastle Road, Galway, Ireland
| | - Gerhard Schlosser
- Centre for Research in Medical Devices (CÚRAM), National University of Ireland, Galway, Biomedical Sciences Building, Newcastle Road, Galway, Ireland. .,School of Natural Sciences and Regenerative Medicine Institute (REMEDI), National University of Ireland, Galway, Biomedical Sciences Building, Newcastle Road, Galway, Ireland.
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Fong LWR, Yang DC, Chen CH. Myristoylated alanine-rich C kinase substrate (MARCKS): a multirole signaling protein in cancers. Cancer Metastasis Rev 2018; 36:737-747. [PMID: 29039083 DOI: 10.1007/s10555-017-9709-6] [Citation(s) in RCA: 41] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Emerging evidence implicates myristoylated alanine-rich C-kinase substrate (MARCKS), a major substrate of protein kinase C (PKC), in a critical role for cancer development and progression. MARCKS is tethered to the plasma membrane but can shuttle between the cytosol and plasma membrane via the myristoyl-electrostatic switch. Phosphorylation of MARCKS by PKC leads to its translocation from the plasma membrane to the cytosol where it functions in actin cytoskeletal remodeling, Ca2+ signaling through binding to calmodulin, and regulation of exocytic vesicle release in secretory cells such as neurons and airway goblet cells. Although the contribution of MARCKS to various cellular processes has been extensively studied, its roles in neoplastic disease have been conflicting. This review highlights the molecular and functional differences of MARCKS that exist between normal and tumor cells. We also discuss the recent advances in the potential roles of MARCKS in tumorigenesis, metastasis, and resistance to anti-cancer therapies, with a focus on addressing the inconsistent results regarding the function of MARCKS as a promoter or inhibitor of oncogenesis.
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Affiliation(s)
- Lon Wolf R Fong
- Department of Experimental Therapeutics, Division of Cancer Medicine, The University of Texas MD Anderson Cancer Center, Houston, TX, USA
| | - David C Yang
- Department of Internal Medicine, Division of Pulmonary and Critical Care Medicine and Center for Comparative Respiratory Biology and Medicine, University of California Davis, Davis, CA, USA.,Division of Nephrology, Department of Internal Medicine, University of California Davis, Davis, CA, 95616, USA
| | - Ching-Hsien Chen
- Division of Nephrology, Department of Internal Medicine, University of California Davis, Davis, CA, 95616, USA. .,Comprehensive Cancer Center, University of California Davis, Davis, CA, USA.
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12
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Lakshmi SP, Reddy AT, Reddy RC. Emerging pharmaceutical therapies for COPD. Int J Chron Obstruct Pulmon Dis 2017; 12:2141-2156. [PMID: 28790817 PMCID: PMC5531723 DOI: 10.2147/copd.s121416] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
Abstract
COPD, for which cigarette smoking is the major risk factor, remains a worldwide burden. Current therapies provide only limited short-term benefit and fail to halt progression. A variety of potential therapeutic targets are currently being investigated, including COPD-related proinflammatory mediators and signaling pathways. Other investigational compounds target specific aspects or complications of COPD such as mucus hypersecretion and pulmonary hypertension. Although many candidate therapies have shown no significant effects, other emerging therapies have improved lung function, pulmonary hypertension, glucocorticoid sensitivity, and/or the frequency of exacerbations. Among these are compounds that inhibit the CXCR2 receptor, mitogen-activated protein kinase/Src kinase, myristoylated alanine-rich C kinase substrate, selectins, and the endothelin receptor. Activation of certain transcription factors may also be relevant, as a large retrospective cohort study of COPD patients with diabetes found that the peroxisome proliferator-activated receptor γ (PPARγ) agonists rosiglitazone and pioglitazone were associated with reduced COPD exacerbation rate. Notably, several therapies have shown efficacy only in identifiable subgroups of COPD patients, suggesting that subgroup identification may become more important in future treatment strategies. This review summarizes the status of emerging therapeutic pharmaceuticals for COPD and highlights those that appear most promising.
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Affiliation(s)
- Sowmya P Lakshmi
- Department of Medicine, Division of Pulmonary, Allergy and Critical Care Medicine, University of Pittsburgh School of Medicine.,Veterans Affairs Pittsburgh Healthcare System, Pittsburgh, PA, USA
| | - Aravind T Reddy
- Department of Medicine, Division of Pulmonary, Allergy and Critical Care Medicine, University of Pittsburgh School of Medicine.,Veterans Affairs Pittsburgh Healthcare System, Pittsburgh, PA, USA
| | - Raju C Reddy
- Department of Medicine, Division of Pulmonary, Allergy and Critical Care Medicine, University of Pittsburgh School of Medicine.,Veterans Affairs Pittsburgh Healthcare System, Pittsburgh, PA, USA
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In Vitro Neutrophil Migration Requires Protein Kinase C-Delta (δ-PKC)-Mediated Myristoylated Alanine-Rich C-Kinase Substrate (MARCKS) Phosphorylation. Inflammation 2016; 38:1126-41. [PMID: 25515270 DOI: 10.1007/s10753-014-0078-9] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
Dysregulated release of neutrophil reactive oxygen species and proteolytic enzymes contributes to both acute and chronic inflammatory diseases. Therefore, molecular regulators of these processes are potential targets for new anti-inflammatory therapies. We have shown previously that myristoylated alanine-rich C-kinase substrate (MARCKS), a well-known actin binding protein and protein kinase C (PKC) substrate, is a key regulator of neutrophil functions. In the current study, we investigate the role of PKC-mediated MARCKS phosphorylation in neutrophil migration and adhesion in vitro. We report that treatment of human neutrophils with the δ-PKC inhibitor rottlerin significantly attenuates f-Met-Leu-Phe (fMLF)-induced MARCKS phosphorylation (IC50=5.709 μM), adhesion (IC50=8.4 μM), and migration (IC50=6.7 μM), while α-, β-, and ζ-PKC inhibitors had no significant effect. We conclude that δ-PKC-mediated MARCKS phosphorylation is essential for human neutrophil migration and adhesion in vitro. These results implicate δ-PKC-mediated MARCKS phosphorylation as a key step in the inflammatory response of neutrophils.
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Babu KS, Morjaria JB. Emerging therapeutic strategies in COPD. Drug Discov Today 2014; 20:371-9. [PMID: 25462534 DOI: 10.1016/j.drudis.2014.11.003] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2014] [Revised: 10/19/2014] [Accepted: 11/06/2014] [Indexed: 01/10/2023]
Abstract
Chronic obstructive pulmonary disease (COPD) management is changing with the advent of newer inhaled medications and devices that belong to the current group of therapies [i.e. inhaled corticosteroid (ICS), long-acting β2 agonists (LABAs) and long-acting muscarinic antagonists (LAMAs)], providing patients as well as physicians with a wider range of options. In this review, we examine Phase II studies currently underway in COPD patients. With improved understanding of the condition, the role for biological and immunomodulatory therapies in COPD patients is also an interesting and important aspect looked upon with great enthusiasm. It is indeed interesting to note that the future COPD treatment options could include novel interventional strategies in addition to innovative inhaled therapies, which have been the backbone of COPD management for the past couple of decades.
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Affiliation(s)
- Kesavan S Babu
- Dept of Respiratory Medicine, Queen Alexandra Hospital, Southwick Road, Cosham, Portsmouth PO6 3LY, UK
| | - Jaymin B Morjaria
- Dept of Academic Respiratory Medicine, Hull York Medical School, University of Hull, Castle Hill Hospital, Castle Road, Cottingham HU16 5JQ, UK.
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Shi J, Birnbaumer L, Large WA, Albert AP. Myristoylated alanine-rich C kinase substrate coordinates native TRPC1 channel activation by phosphatidylinositol 4,5-bisphosphate and protein kinase C in vascular smooth muscle. FASEB J 2013; 28:244-55. [PMID: 24022404 DOI: 10.1096/fj.13-238022] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Canonical transient receptor potential 1 (TRPC1) Ca(2+)-permeable cation channels contribute to vascular tone and blood vessel remodeling and represent potential therapeutic targets for cardiovascular disease. Protein kinase C (PKC) and phosphatidylinositol 4,5-bisphosphate [PI(4,5)P2] are obligatory for native TRPC1 channel activation in vascular smooth muscle cells (VSMCs) but how PKC and PI(4,5)P2 act together to induce channel gating remains unresolved. The present study reveals that myristoylated alanine-rich C kinase substrate (MARCKS) protein coordinates activation of TRPC1 channels by PKC and PI(4,5)P2. TRPC1 channels and MARCKS form signaling complexes with PI(4,5)P2 bound to MARCKS; in this configuration TRPC1 channels are closed. Activators of TRPC1 channels induce PKC phosphorylation of TRPC1 proteins, which causes dissociation of TRPC1 subunits from MARCKS and release of PI(4,5)P2 from MARCKS; PI(4,5)P2 subsequently binds to TRPC1 subunits to induce channel opening. Calmodulin acting at, or upstream of, MARCKS is also required for TRPC1 channel opening through a similar gating mechanism involving PKC and PI(4,5)P2. These novel findings show that MARCKS coordinates native TRPC1 channel activation in VSMCs by acting as a reversible PI(4,5)P2 buffer, which is regulated by PKC-mediated TRPC1 phosphorylation. Moreover, our data provide evidence that PI(4,5)P2 is a gating ligand of TRPC1 channels.
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Affiliation(s)
- Jian Shi
- 1Pharmacology and Cell Physiology, Division of Biomedical Sciences, St. George's, University of London, Cranmer Terrace, London SW17 0RE, UK.
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Karunakaran D, Kockx M, Owen DM, Burnett JR, Jessup W, Kritharides L. Protein kinase C controls vesicular transport and secretion of apolipoprotein E from primary human macrophages. J Biol Chem 2013; 288:5186-97. [PMID: 23288845 DOI: 10.1074/jbc.m112.428961] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Macrophage-specific apolipoprotein E (apoE) secretion plays an important protective role in atherosclerosis. However, the precise signaling mechanisms regulating apoE secretion from primary human monocyte-derived macrophages (HMDMs) remain unclear. Here we investigate the role of protein kinase C (PKC) in regulating basal and stimulated apoE secretion from HMDMs. Treatment of HMDMs with structurally distinct pan-PKC inhibitors (calphostin C, Ro-31-8220, Go6976) and a PKC inhibitory peptide all significantly decreased apoE secretion without significantly affecting apoE mRNA or apoE protein levels. The PKC activator phorbol 12-myristate 13-acetate (PMA) stimulated apoE secretion, and both PMA-induced and apoAI-induced apoE secretion were inhibited by PKC inhibitors. PKC regulation of apoE secretion was found to be independent of the ATP binding cassette transporter ABCA1. Live cell imaging demonstrated that PKC inhibitors inhibited vesicular transport of apoE to the plasma membrane. Pharmacological or peptide inhibitor and knockdown studies indicate that classical isoforms PKCα/β and not PKCδ, -ε, -θ, or -ι/ζ isoforms regulate apoE secretion from HMDMs. The activity of myristoylated alanine-rich protein kinase C substrate (MARCKS) correlated with modulation of PKC activity in these cells, and direct peptide inhibition of MARCKS inhibited apoE secretion, implicating MARCKS as a downstream effector of PKC in apoE secretion. Comparison with other secreted proteins indicated that PKC similarly regulated secretion of matrix metalloproteinase 9 and chitinase-3-like-1 protein but differentially affected the secretion of other proteins. In conclusion, PKC regulates the secretion of apoE from primary human macrophages.
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Affiliation(s)
- Denuja Karunakaran
- Centre for Vascular Research, School of Medical Sciences, University of New South Wales, Sydney, Australia
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Li J, D'Annibale-Tolhurst MA, Adler KB, Fang S, Yin Q, Birkenheuer AJ, Levy MG, Jones SL, Sung EJ, Hawkins EC, Yoder JA, Nordone SK. A myristoylated alanine-rich C kinase substrate-related peptide suppresses cytokine mRNA and protein expression in LPS-activated canine neutrophils. Am J Respir Cell Mol Biol 2012; 48:314-21. [PMID: 23221047 DOI: 10.1165/rcmb.2012-0278oc] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
Myristoylated alanine-rich C kinase substrate (MARCKS) is a ubiquitously expressed protein kinase C substrate that has emerged as a potential therapeutic target for the amelioration of mucin secretion and inflammation in patients with chronic obstructive pulmonary disease. MARCKS also plays a key role in regulating the adhesion, migration, and degranulation of neutrophils. Moreover, given its biological role in epithelial and immune cells, we hypothesized that MARCKS may play an integral role in cytokine secretion by neutrophils. Because the amino terminus of MARCKS is highly conserved across vertebrate species, we successfully applied the well-characterized human MARCKS inhibitory peptide, myristoylated N-terminal sequence (MANS), to attenuate the function of MARCKS in isolated canine neutrophils. Pretreatment of canine neutrophils with MANS peptide significantly reduced both mRNA and protein expression in a broad range of LPS-induced cytokines, including IL-8, a chemokine (C-X-C motif) ligand-1 orthologue, and TNF-α, in comparison with untreated cells or those treated with a control peptide. This reduction in cytokine expression was observed even when neutrophils were treated with MANS 2 hours after LPS exposure. The observed reduction in cytokine secretion was not attributable to protein retention or cell death, but was associated with reduced cytokine transcript synthesis. These observations identify MARCKS protein as a promising therapeutic target in the treatment of inflammatory diseases or syndromes attributed to neutrophil influx and inflammatory cytokine production, such as sepsis, acute lung injury, and acute respiratory distress syndrome.
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Affiliation(s)
- Jingjing Li
- Comparative Biomedical Sciences Graduate Program, North Carolina State University, Raleigh, NC 27606, USA
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Sealing of Transected Neurites of Rat B104 Cells Requires a Diacylglycerol PKC-Dependent Pathway and a PKA-Dependent Pathway. Cell Mol Neurobiol 2012; 33:31-46. [DOI: 10.1007/s10571-012-9868-5] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2012] [Accepted: 07/19/2012] [Indexed: 10/28/2022]
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Green TD, Park J, Yin Q, Fang S, Crews AL, Jones SL, Adler KB. Directed migration of mouse macrophages in vitro involves myristoylated alanine-rich C-kinase substrate (MARCKS) protein. J Leukoc Biol 2012; 92:633-9. [PMID: 22623357 DOI: 10.1189/jlb.1211604] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
A role for MARCKS protein in directed migration of macrophages toward a chemoattractant was investigated. A peptide identical to the N-terminus of MARCKS (the MANS peptide), shown previously to inhibit the function of MARCKS in various cell types, was used. We investigated whether this MARCKS-related peptide could affect migration of macrophages, using the mouse macrophage-like J774A.1 cell line and primary murine macrophages. Both of these cell types migrated in response to the chemoattractants macrophage/MCPs, MCP-1 (25-100 ng/ml) or C5a (5-20 ng/ml). Cells were preincubated (15 min) with MANS or a mis-sense control peptide (RNS), both at 50 μM, and effects on migration determined 3 h after addition of chemoattractants. The movement and interactions of MARCKS and actin also were followed visually via confocal microscopy using a fluorescently labeled antibody to MARCKS and fluorescently tagged phalloidin to identify actin. MANS, but not RNS, attenuated migration of J774A.1 cells and primary macrophages in response to MCP-1 or C5a, implicating MARCKS in the cellular mechanism of directed migration. Exposure of cells to MCP-1 resulted in rapid phosphorylation and translocation of MARCKS from plasma membrane to cytosol, whereas actin appeared to spread through the cell and into cell protrusions; there was visual and biochemical evidence of a transient interaction between MARCKS and actin during the process of migration. These results suggest that MARCKS is involved in directed migration of macrophages via a process involving its phosphorylation, cytoplasmic translocation, and interaction with actin.
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Affiliation(s)
- Teresa D Green
- Department of Molecular Biomedical Sciences, North Carolina State University, College of Veterinary Medicine, Raleigh, NC, USA
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Banerjee A, Trivedi CM, Damera G, Jiang M, Jester W, Hoshi T, Epstein JA, Panettieri RA. Trichostatin A abrogates airway constriction, but not inflammation, in murine and human asthma models. Am J Respir Cell Mol Biol 2012; 46:132-8. [PMID: 22298527 DOI: 10.1165/rcmb.2010-0276oc] [Citation(s) in RCA: 58] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
Histone deacetylase (HDAC) inhibitors may offer novel approaches in the treatment of asthma. We postulate that trichostatin A (TSA), a Class 1 and 2 inhibitor of HDAC, inhibits airway hyperresponsiveness in antigen-challenged mice. Mice were sensitized and challenged with Aspergillus fumigatus antigen (AF) and treated with TSA, dexamethasone, or vehicle. Lung resistance (R(L)) and dynamic compliance were measured, and bronchial alveolar lavage fluid (BALF) was analyzed for numbers of leukocytes and concentrations of cytokines. Human precision-cut lung slices (PCLS) were treated with TSA and their agonist-induced bronchoconstriction was measured, and TSA-treated human airway smooth muscle (ASM) cells were evaluated for the agonist-induced activation of Rho and intracellular release of Ca(2+). The activity of HDAC in murine lungs was enhanced by antigen and abrogated by TSA. TSA also inhibited methacholine (Mch)-induced increases in R(L) and decreases in dynamic compliance in naive control mice and in AF-sensitized and -challenged mice. Total cell counts, concentrations of IL-4, and numbers of eosinophils in BALF were unchanged in mice treated with TSA or vehicle, whereas dexamethasone inhibited the numbers of eosinophils in BALF and concentrations of IL-4. TSA inhibited the carbachol-induced contraction of PCLS. Treatment with TSA inhibited the intracellular release of Ca(2+) in ASM cells in response to histamine, without affecting the activation of Rho. The inhibition of HDAC abrogates airway hyperresponsiveness to Mch in both naive and antigen-challenged mice. TSA inhibits the agonist-induced contraction of PCLS and mobilization of Ca(2+) in ASM cells. Thus, HDAC inhibitors demonstrate a mechanism of action distinct from that of anti-inflammatory agents such as steroids, and represent a promising therapeutic agent for airway disease.
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Affiliation(s)
- Audreesh Banerjee
- Translational Research Laboratories, Division of Pulmonary, Allergy, and Critical Care Medicine, University of Pennsylvania Medical Center, 125 South 31st St., Translational Research Laboratories, Philadelphia, PA 19104-3403, USA.
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Green TD, Crews AL, Park J, Fang S, Adler KB. Regulation of mucin secretion and inflammation in asthma: a role for MARCKS protein? Biochim Biophys Acta Gen Subj 2011; 1810:1110-3. [PMID: 21281703 DOI: 10.1016/j.bbagen.2011.01.009] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2010] [Revised: 01/14/2011] [Accepted: 01/21/2011] [Indexed: 10/18/2022]
Abstract
BACKGROUND A major characteristic of asthmatic airways is an increase in mucin (the glycoprotein component of mucus) producing and secreting cells, which leads to increased mucin release that further clogs constricted airways and contributes markedly to airway obstruction and, in the most severe cases, to status asthmaticus. Asthmatic airways show both a hyperplasia and metaplasia of goblet cells, mucin-producing cells in the epithelium; hyperplasia refers to enhanced numbers of goblet cells in larger airways, while metaplasia refers to the appearance of these cells in smaller airways where they normally are not seen. With the number of mucin-producing and secreting cells increased, there is a coincident hypersecretion of mucin which characterizes asthma. On a cellular level, a major regulator of airway mucin secretion in both in vitro and in vivo studies has been shown to be MARCKS (myristoylated alanine-rich C kinase substrate) protein, a ubiquitous substrate of protein kinase C (PKC). GENERAL SIGNIFICANCE In this review, properties of MARCKS and how the protein may regulate mucin secretion at a cellular level will be discussed. In addition, the roles of MARCKS in airway inflammation related to both influx of inflammatory cells into the lung and release of granules containing inflammatory mediators by these cells will be explored. This article is part of a Special Issue entitled: Biochemistry of Asthma.
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Affiliation(s)
- Teresa D Green
- Deparment of Molecualr Biomedical Sciences, North Carolina State University CVM, Raleigh, NC 27606, USA
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