1
|
McCullough M, Joshi IV, Pereira NL, Fuentes N, Krishnan R, Druey KM. Targeting cytoskeletal biomechanics to modulate airway smooth muscle contraction in asthma. J Biol Chem 2024; 301:108028. [PMID: 39615690 DOI: 10.1016/j.jbc.2024.108028] [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: 06/05/2024] [Revised: 10/13/2024] [Accepted: 10/28/2024] [Indexed: 12/21/2024] Open
Abstract
To contract, to deform, and remodel, the airway smooth muscle cell relies on dynamic changes in the structure of its mechanical force-bearing cytoskeleton. These alternate between a "fluid-like" (relaxed) state characterized by weak contractile protein-protein interactions within the cytoskeletal apparatus and a "solid-like" (contractile) state promoted by strong and highly organized molecular interactions. In this review, we discuss the roles for actin, myosin, factors promoting actin polymerization and depolymerization, adhesome complexes, and cell-cell junctions in these dynamic processes. We describe the relationship between these cytoskeletal factors, extracellular matrix components of bronchial tissue, and mechanical stretch and other changes within the airway wall in the context of the physical mechanisms of cytoskeletal fluidization-resolidification. We also highlight studies that emphasize the distinct processes of cell shortening and force transmission in airway smooth muscle and previously unrecognized roles for actin in cytoskeletal dynamics. Finally, we discuss the implications of these discoveries for understanding and treating airway obstruction in asthma.
Collapse
Affiliation(s)
- Morgan McCullough
- Lung and Vascular Inflammation Section, Laboratory of Allergic Diseases, National Institute of Allergy and Infectious Diseases, National Institutes of Health; Bethesda, Maryland, USA
| | - Ilin V Joshi
- Lung and Vascular Inflammation Section, Laboratory of Allergic Diseases, National Institute of Allergy and Infectious Diseases, National Institutes of Health; Bethesda, Maryland, USA
| | - Nicolas L Pereira
- Lung and Vascular Inflammation Section, Laboratory of Allergic Diseases, National Institute of Allergy and Infectious Diseases, National Institutes of Health; Bethesda, Maryland, USA
| | - Nathalie Fuentes
- Lung and Vascular Inflammation Section, Laboratory of Allergic Diseases, National Institute of Allergy and Infectious Diseases, National Institutes of Health; Bethesda, Maryland, USA
| | - Ramaswamy Krishnan
- Center for Vascular Biology Research, Department of Emergency Medicine, Beth Israel Deaconess Medical Center; Boston, Massachusetts, USA
| | - Kirk M Druey
- Lung and Vascular Inflammation Section, Laboratory of Allergic Diseases, National Institute of Allergy and Infectious Diseases, National Institutes of Health; Bethesda, Maryland, USA.
| |
Collapse
|
2
|
Hu S, Wang L, Zheng M, Wang M, Chen B, Lin L. LY333531 attenuates contraction of tumor necrosis factor-α-sensitized human airway smooth muscle cells. J Asthma 2024; 61:1514-1522. [PMID: 38833524 DOI: 10.1080/02770903.2024.2364810] [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: 11/14/2023] [Revised: 05/14/2024] [Accepted: 06/02/2024] [Indexed: 06/06/2024]
Abstract
OBJECTIVE Protein kinase C (PKC) has been implicated in the increased contraction of human airway smooth muscle cells (HASMCs) in asthma. Using the three-dimensional collagen gel contraction system, the study aimed to determine the effects of LY333531, a specific inhibitor of the PKC-β isoform, on the contraction of tumor necrosis factor (TNF)-α-sensitized HASMCs. METHODS Cultured HASMCs were divided into five groups: the control group received no treatment, and the cells in the TNF-α group were sensitized with 10 ng/mL TNF-α for 48 h, while TNF-α was administered to sensitize HASMCs in the presence of 0.1, 0.2, and 0.5 μM LY333531 for 48 h in the 0.1LY, 0.2LY, and 0.5LY groups, respectively. Following this, HASMCs contraction was stimulated with 1 mM acetylcholine (ACh) for up to 24 h in each group and assessed using a three-dimensional collagen gel contraction assay. Furthermore, western blot and immunofluorescence analysis were performed. RESULTS The collagen gel contraction assay revealed that TNF-α increased the protein expression of phosphorylated PKC-β2, CPI-17, and MLC while exacerbating ACh-induced HASMCs contraction. LY333531 significantly attenuated HASMCs contraction and downregulated the protein expression of both p-CPI-17 and p-MLC. CONCLUSIONS At least in part by regulating CPI-17 and MLC phosphorylation, LY333531 attenuates augmented contraction of TNF-α-sensitized HASMCs in a collagen gel contraction system.
Collapse
Affiliation(s)
- Shuyu Hu
- Department of Anesthesiology, The First Affiliated Hospital of Wenzhou Medical University, Wenzhou, Zhejiang, China
| | - Liangrong Wang
- Department of Anesthesiology, The First Affiliated Hospital of Wenzhou Medical University, Wenzhou, Zhejiang, China
| | - Miaomiao Zheng
- Department of Anesthesiology, The First Affiliated Hospital of Wenzhou Medical University, Wenzhou, Zhejiang, China
| | - Mengjia Wang
- Department of Anesthesiology, The First Affiliated Hospital of Wenzhou Medical University, Wenzhou, Zhejiang, China
| | - Baihui Chen
- Department of Anesthesiology, The First Affiliated Hospital of Wenzhou Medical University, Wenzhou, Zhejiang, China
| | - Lina Lin
- Department of Anesthesiology, The First Affiliated Hospital of Wenzhou Medical University, Wenzhou, Zhejiang, China
| |
Collapse
|
3
|
Cui YF, Lu QH, Huang X, Lin WN, Huang T, Yang Q. [Effects of inhibition of Rho/ROCK pathway on proliferation and migration of airway smooth muscle cells and related mechanisms]. ZHONGGUO DANG DAI ER KE ZA ZHI = CHINESE JOURNAL OF CONTEMPORARY PEDIATRICS 2024; 26:974-981. [PMID: 39267514 PMCID: PMC11404462 DOI: 10.7499/j.issn.1008-8830.2405119] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 09/17/2024]
Abstract
OBJECTIVES To investigate the effects and molecular mechanisms of inhibition of the Ras homolog gene (Rho)/Rho-associated coiled-coil forming protein kinase (ROCK) pathway on the proliferation and migration of airway smooth muscle cells involving myocardin (MYOCD). METHODS Human airway smooth muscle cells were infected with the adenoviral vector Ad-ZsGreen-shRNA-hROCK1 in vitro. The cells were randomly divided into four groups: ROCK1 gene silencing control (shNC) group, shNC + arachidonic acid (AA, Rho/ROCK pathway activator) group, ROCK1 gene silencing (shROCK1) group, and shROCK1 + AA group (n=3 each). Quantitative real-time polymerase chain reaction and Western blot were used to detect the expression levels of ROCK1 and MYOCD mRNA and protein. ELISA was employed to measure the levels of globular actin and filamentous actin, while immunofluorescent staining and scratch assays were utilized to assess cell proliferation and migration. RESULTS Compared to the shNC + AA group, the shROCK1 + AA group exhibited decreased levels of ROCK1 and MYOCD mRNA and protein expression, reduced expression levels of globular actin and filamentous actin, and diminished cell proliferation and migration capabilities (P<0.05). CONCLUSIONS Inhibition of the Rho/ROCK pathway suppresses the proliferation and migration of airway smooth muscle cells, which may be associated with the downregulation of MYOCD.
Collapse
Affiliation(s)
- Yun-Fei Cui
- Department of Respiratory Medicine, Shenzhen Children's Hospital, Shenzhen, Guangdong 518036, China
| | - Qing-Hua Lu
- Department of Respiratory Medicine, Shenzhen Children's Hospital, Shenzhen, Guangdong 518036, China
| | - Xiao Huang
- Department of Respiratory Medicine, Shenzhen Children's Hospital, Shenzhen, Guangdong 518036, China
| | - Wei-Nan Lin
- Department of Respiratory Medicine, Shenzhen Children's Hospital, Shenzhen, Guangdong 518036, China
| | - Ting Huang
- Department of Respiratory Medicine, Shenzhen Children's Hospital, Shenzhen, Guangdong 518036, China
| | - Qin Yang
- Department of Respiratory Medicine, Shenzhen Children's Hospital, Shenzhen, Guangdong 518036, China
| |
Collapse
|
4
|
Li Y, Yang T, Jiang B. Neutrophil and neutrophil extracellular trap involvement in neutrophilic asthma: A review. Medicine (Baltimore) 2024; 103:e39342. [PMID: 39183388 PMCID: PMC11346896 DOI: 10.1097/md.0000000000039342] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/05/2024] [Revised: 03/21/2024] [Accepted: 07/26/2024] [Indexed: 08/27/2024] Open
Abstract
Asthma is a highly prevalent chronic inflammatory disease characterized by variable airflow obstruction and airway hyperresponsiveness. Neutrophilic asthma (NA) is classified as "type 2 low" asthma, defined as 65% or more neutrophils in the total cell count. There is no clear consensus on the pathogenesis of NA, and the accumulation of neutrophils and release of neutrophil extracellular traps (NETs) may be responsible for its development. A NET is a large extracellular meshwork comprising cell membrane and granule proteins. It is a powerful antimicrobial defence system that traps, neutralizes, and kills bacteria, fungi, viruses, and parasites and prevents the spread of microorganisms. However, dysregulation of NETs may lead to chronic airway inflammation, is associated with worsening of asthma, and has been the subject of major research advances in chronic lung diseases in recent years. NA is insensitive to steroids, and there is a need to find effective biomarkers as targets for the treatment of NA to replace steroids. This review analyses the mechanisms of action between asthmatic neutrophil recruitment and NET formation and their impact on NA development. It also discusses their possible therapeutic significance in NA, summarizing the advances made in NA agents and providing strategies for the treatment of NA, provide a theoretical basis for the development of new therapeutic drugs, thereby improving the level of diagnosis and treatment, and promoting the research progress in the field of asthma.
Collapse
Affiliation(s)
- Yuemu Li
- Institutes of Integrative Medicine, Heilongjiang Provincial Hospital of Traditional Chinese Medicine, Heilongjiang, China
| | - Tianyi Yang
- Institutes of Integrative Medicine, Heilongjiang Provincial Hospital of Traditional Chinese Medicine, Heilongjiang, China
| | - Baihua Jiang
- Institutes of Integrative Medicine, Heilongjiang Provincial Hospital of Traditional Chinese Medicine, Heilongjiang, China
| |
Collapse
|
5
|
Mohammad Taheri M, Javan F, Poudineh M, Athari SS. Beyond CAR-T: The rise of CAR-NK cell therapy in asthma immunotherapy. J Transl Med 2024; 22:736. [PMID: 39103889 PMCID: PMC11302387 DOI: 10.1186/s12967-024-05534-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2024] [Accepted: 07/23/2024] [Indexed: 08/07/2024] Open
Abstract
Asthma poses a major public health burden. While existing asthma drugs manage symptoms for many, some patients remain resistant. The lack of a cure, especially for severe asthma, compels exploration of novel therapies. Cancer immunotherapy successes with CAR-T cells suggest its potential for asthma treatment. Researchers are exploring various approaches for allergic diseases including membrane-bound IgE, IL-5, PD-L2, and CTLA-4 for asthma, and Dectin-1 for fungal asthma. NK cells offer several advantages over T cells for CAR-based immunotherapy. They offer key benefits: (1) HLA compatibility, meaning they can be used in a wider range of patients without the need for matching tissue types. (2) Minimal side effects (CRS and GVHD) due to their limited persistence and cytokine profile. (3) Scalability for "off-the-shelf" production from various sources. Several strategies have been introduced that highlight the superiority and challenges of CAR-NK cell therapy for asthma treatment including IL-10, IFN-γ, ADCC, perforin-granzyme, FASL, KIR, NCRs (NKP46), DAP, DNAM-1, TGF-β, TNF-α, CCL, NKG2A, TF, and EGFR. Furthermore, we advocate for incorporating AI for CAR design optimization and CRISPR-Cas9 gene editing technology for precise gene manipulation to generate highly effective CAR constructs. This review will delve into the evolution and production of CAR designs, explore pre-clinical and clinical studies of CAR-based therapies in asthma, analyze strategies to optimize CAR-NK cell function, conduct a comparative analysis of CAR-T and CAR-NK cell therapy with their respective challenges, and finally present established novel CAR designs with promising potential for asthma treatment.
Collapse
Affiliation(s)
| | - Fatemeh Javan
- Student Research Committee, School of Medicine, Zanjan University of Medical Sciences, Zanjan, Iran
| | - Mohadeseh Poudineh
- Student Research Committee, School of Medicine, Zanjan University of Medical Sciences, Zanjan, Iran
| | - Seyed Shamseddin Athari
- Cancer Gene Therapy Research Center, Zanjan University of Medical Sciences, Zanjan, Iran.
- Department of Immunology, Zanjan School of Medicine, Zanjan University of Medical Sciences, 12th Street, Shahrake Karmandan, Zanjan, 45139-561111, Iran.
| |
Collapse
|
6
|
Goyal RK, Rattan S. Role of mechanoregulation in mast cell-mediated immune inflammation of the smooth muscle in the pathophysiology of esophageal motility disorders. Am J Physiol Gastrointest Liver Physiol 2024; 326:G398-G410. [PMID: 38290993 PMCID: PMC11213482 DOI: 10.1152/ajpgi.00258.2023] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/06/2023] [Revised: 01/15/2024] [Accepted: 01/29/2024] [Indexed: 02/01/2024]
Abstract
Major esophageal disorders involve obstructive transport of bolus to the stomach, causing symptoms of dysphagia and impaired clearing of the refluxed gastric contents. These may occur due to mechanical constriction of the esophageal lumen or loss of relaxation associated with deglutitive inhibition, as in achalasia-like disorders. Recently, immune inflammation has been identified as an important cause of esophageal strictures and the loss of inhibitory neurotransmission. These disorders are also associated with smooth muscle hypertrophy and hypercontractility, whose cause is unknown. This review investigated immune inflammation in the causation of smooth muscle changes in obstructive esophageal bolus transport. Findings suggest that smooth muscle hypertrophy occurs above the obstruction and is due to mechanical stress on the smooth muscles. The mechanostressed smooth muscles release cytokines and other molecules that may recruit and microlocalize mast cells to smooth muscle bundles, so that their products may have a close bidirectional effect on each other. Acting in a paracrine fashion, the inflammatory cytokines induce genetic and epigenetic changes in the smooth muscles, leading to smooth muscle hypercontractility, hypertrophy, and impaired relaxation. These changes may worsen difficulty in the esophageal transport. Immune processes differ in the first phase of obstructive bolus transport, and the second phase of muscle hypertrophy and hypercontractility. Moreover, changes in the type of mechanical stress may change immune response and effect on smooth muscles. Understanding immune signaling in causes of obstructive bolus transport, type of mechanical stress, and associated smooth muscle changes may help pathophysiology-based prevention and targeted treatment of esophageal motility disorders.NEW & NOTEWORTHY Esophageal disorders such as esophageal stricture or achalasia, and diffuse esophageal spasm are associated with smooth muscle hypertrophy and hypercontractility, above the obstruction, yet the cause of such changes is unknown. This review suggests that smooth muscle obstructive disorders may cause mechanical stress on smooth muscle, which then secretes chemicals that recruit, microlocalize, and activate mast cells to initiate immune inflammation, producing functional and structural changes in smooth muscles. Understanding the immune signaling in these changes may help pathophysiology-based prevention and targeted treatment of esophageal motility disorders.
Collapse
Affiliation(s)
- Raj K Goyal
- Division of Gastroenterology, Department of Medicine, Veterans Affairs Boston Healthcare System, West Roxbury, Massachusetts, United States
- Division of Gastroenterology, Hepatology, and Endoscopy, Department of Medicine, Beth Israel Deaconess Medical Center, and Harvard Medical School, Boston, Massachusetts, United States
| | - Satish Rattan
- Department of Medicine, Division of Gastroenterology and Hepatology, Sidney Kummel Medical College of Thomas Jefferson University, Philadelphia, Pennsylvania, United States
| |
Collapse
|
7
|
Lamb FS, Choi H, Miller MR, Stark RJ. Vascular Inflammation and Smooth Muscle Contractility: The Role of Nox1-Derived Superoxide and LRRC8 Anion Channels. Hypertension 2024; 81:752-763. [PMID: 38174563 PMCID: PMC10954410 DOI: 10.1161/hypertensionaha.123.19434] [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] [Indexed: 01/05/2024]
Abstract
Vascular inflammation underlies the development of hypertension, and the mechanisms by which it increases blood pressure remain the topic of intense investigation. Proinflammatory factors including glucose, salt, vasoconstrictors, cytokines, wall stress, and growth factors enhance contractility and impair relaxation of vascular smooth muscle cells. These pathways share a dependence upon redox signaling, and excessive activation promotes oxidative stress that promotes vascular aging. Vascular smooth muscle cell phenotypic switching and migration into the intima contribute to atherosclerosis, while hypercontractility increases systemic vascular resistance and vasospasm that can trigger ischemia. Here, we review factors that drive the initiation and progression of this vasculopathy in vascular smooth muscle cells. Emphasis is placed on the contribution of reactive oxygen species generated by the Nox1 NADPH oxidase which produces extracellular superoxide (O2•-). The mechanisms of O2•- signaling remain poorly defined, but recent evidence demonstrates physical association of Nox1 with leucine-rich repeat containing 8 family volume-sensitive anion channels. These may provide a pathway for influx of O2•- to the cytoplasm, creating an oxidized cytoplasmic nanodomain where redox-based signals can affect both cytoskeletal structure and vasomotor function. Understanding the mechanistic links between inflammation, O2•- and vascular smooth muscle cell contractility may facilitate targeting of anti-inflammatory therapy in hypertension.
Collapse
Affiliation(s)
- Fred S Lamb
- Department of Pediatrics, Vanderbilt University Medical Center, Nashville, TN
| | - Hyehun Choi
- Department of Pediatrics, Vanderbilt University Medical Center, Nashville, TN
| | - Michael R Miller
- Department of Pediatrics, Vanderbilt University Medical Center, Nashville, TN
| | - Ryan J Stark
- Department of Pediatrics, Vanderbilt University Medical Center, Nashville, TN
| |
Collapse
|
8
|
Leung JM, Sin DD. Predicting steroid responsiveness using airway smooth muscle in COPD: a HISTORIC study. Eur Respir J 2023; 62:2300956. [PMID: 37474151 DOI: 10.1183/13993003.00956-2023] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2023] [Accepted: 06/08/2023] [Indexed: 07/22/2023]
Affiliation(s)
- Janice M Leung
- Centre for Heart Lung Innovation, St. Paul's Hospital, University of British Columbia, Vancouver, BC, Canada
- Division of Respiratory Medicine, Department of Medicine, University of British Columbia, Vancouver, BC, Canada
| | - Don D Sin
- Centre for Heart Lung Innovation, St. Paul's Hospital, University of British Columbia, Vancouver, BC, Canada
- Division of Respiratory Medicine, Department of Medicine, University of British Columbia, Vancouver, BC, Canada
| |
Collapse
|
9
|
Tota M, Łacwik J, Laska J, Sędek Ł, Gomułka K. The Role of Eosinophil-Derived Neurotoxin and Vascular Endothelial Growth Factor in the Pathogenesis of Eosinophilic Asthma. Cells 2023; 12:cells12091326. [PMID: 37174726 PMCID: PMC10177218 DOI: 10.3390/cells12091326] [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: 03/10/2023] [Revised: 04/23/2023] [Accepted: 05/04/2023] [Indexed: 05/15/2023] Open
Abstract
Asthma is a chronic complex pulmonary disease characterized by airway inflammation, remodeling, and hyperresponsiveness. Vascular endothelial growth factor (VEGF) and eosinophil-derived neurotoxin (EDN) are two significant mediators involved in the pathophysiology of asthma. In asthma, VEGF and EDN levels are elevated and correlate with disease severity and airway hyperresponsiveness. Diversity in VEGF polymorphisms results in the variability of responses to glucocorticosteroids and leukotriene antagonist treatment. Targeting VEGF and eosinophils is a promising therapeutic approach for asthma. We identified lichochalcone A, bevacizumab, azithromycin (AZT), vitamin D, diosmetin, epigallocatechin gallate, IGFBP-3, Neovastat (AE-941), endostatin, PEDF, and melatonin as putative add-on drugs in asthma with anti-VEGF properties. Further studies and clinical trials are needed to evaluate the efficacy of those drugs. AZT reduces the exacerbation rate and may be considered in adults with persistent symptomatic asthma. However, the long-term effects of AZT on community microbial resistance require further investigation. Vitamin D supplementation may enhance corticosteroid responsiveness. Herein, anti-eosinophil drugs are reviewed. Among them are, e.g., anti-IL-5 (mepolizumab, reslizumab, and benralizumab), anti-IL-13 (lebrikizumab and tralokinumab), anti-IL-4 and anti-IL-13 (dupilumab), and anti-IgE (omalizumab) drugs. EDN over peripheral blood eosinophil count is recommended to monitor the asthma control status and to assess the efficacy of anti-IL-5 therapy in asthma.
Collapse
Affiliation(s)
- Maciej Tota
- Student Scientific Group of Adult Allergology, Clinical Department of Internal Medicine, Pneumology and Allergology, Wroclaw Medical University, 50-369 Wrocław, Poland
| | - Julia Łacwik
- Student Scientific Group of Microbiology and Immunology, Department of Microbiology and Immunology, Zabrze, Medical University of Silesia in Katowice, 40-055 Katowice, Poland
| | - Julia Laska
- Student Scientific Group of Microbiology and Immunology, Department of Microbiology and Immunology, Zabrze, Medical University of Silesia in Katowice, 40-055 Katowice, Poland
| | - Łukasz Sędek
- Department of Microbiology and Immunology, Zabrze, Medical University of Silesia in Katowice, 40-055 Katowice, Poland
| | - Krzysztof Gomułka
- Clinical Department of Internal Medicine, Pneumology and Allergology, Wroclaw Medical University, 50-369 Wrocław, Poland
| |
Collapse
|
10
|
Dasgupta D, Mahadev Bhat S, Price AL, Delmotte P, Sieck GC. Molecular Mechanisms Underlying TNFα-Induced Mitochondrial Biogenesis in Human Airway Smooth Muscle. Int J Mol Sci 2023; 24:5788. [PMID: 36982859 PMCID: PMC10055892 DOI: 10.3390/ijms24065788] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2023] [Revised: 03/10/2023] [Accepted: 03/15/2023] [Indexed: 03/22/2023] Open
Abstract
Proinflammatory cytokines such as TNFα mediate airway inflammation. Previously, we showed that TNFα increases mitochondrial biogenesis in human ASM (hASM) cells, which is associated with increased PGC1α expression. We hypothesized that TNFα induces CREB and ATF1 phosphorylation (pCREBS133 and pATF1S63), which transcriptionally co-activate PGC1α expression. Primary hASM cells were dissociated from bronchiolar tissue obtained from patients undergoing lung resection, cultured (one-three passages), and then differentiated by serum deprivation (48 h). hASM cells from the same patient were divided into two groups: TNFα (20 ng/mL) treated for 6 h and untreated controls. Mitochondria were labeled using MitoTracker green and imaged using 3D confocal microscopy to determine mitochondrial volume density. Mitochondrial biogenesis was assessed based on relative mitochondrial DNA (mtDNA) copy number determined by quantitative real-time PCR (qPCR). Gene and/or protein expression of pCREBS133, pATF1S63, PCG1α, and downstream signaling molecules (NRFs, TFAM) that regulate transcription and replication of the mitochondrial genome, were determined by qPCR and/or Western blot. TNFα increased mitochondrial volume density and mitochondrial biogenesis in hASM cells, which was associated with an increase in pCREBS133, pATF1S63 and PCG1α expression, with downstream transcriptional activation of NRF1, NRF2, and TFAM. We conclude that TNFα increases mitochondrial volume density in hASM cells via a pCREBS133/pATF1S63/PCG1α-mediated pathway.
Collapse
Affiliation(s)
| | | | | | | | - Gary C. Sieck
- Department of Physiology & Biomedical Engineering, Mayo Clinic, Rochester, MN 55905, USA
| |
Collapse
|
11
|
Goodwin K, Lemma B, Zhang P, Boukind A, Nelson CM. Plasticity in airway smooth muscle differentiation during mouse lung development. Dev Cell 2023; 58:338-347.e4. [PMID: 36868232 PMCID: PMC10149112 DOI: 10.1016/j.devcel.2023.02.002] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2022] [Revised: 11/27/2022] [Accepted: 02/06/2023] [Indexed: 03/05/2023]
Abstract
It has been proposed that smooth muscle differentiation may physically sculpt airway epithelial branches in mammalian lungs. Serum response factor (SRF) acts with its co-factor myocardin to activate the expression of contractile smooth muscle markers. In the adult, however, smooth muscle exhibits a variety of phenotypes beyond contractile, and these are independent of SRF/myocardin-induced transcription. To determine whether a similar phenotypic plasticity is exhibited during development, we deleted Srf from the mouse embryonic pulmonary mesenchyme. Srf-mutant lungs branch normally, and the mesenchyme displays mechanical properties indistinguishable from controls. scRNA-seq identified an Srf-null smooth muscle cluster, wrapping the airways of mutant lungs, which lacks contractile smooth muscle markers but retains many features of control smooth muscle. Srf-null embryonic airway smooth muscle exhibits a synthetic phenotype, compared with the contractile phenotype of mature wild-type airway smooth muscle. Our findings identify plasticity in embryonic airway smooth muscle and demonstrate that a synthetic smooth muscle layer promotes airway branching morphogenesis.
Collapse
Affiliation(s)
- Katharine Goodwin
- Lewis-Sigler Institute for Integrative Genomics, Princeton University, Princeton, NJ 08544, USA
| | - Bezia Lemma
- Department of Chemical and Biological Engineering, Princeton University, Princeton, NJ 08544, USA
| | - Pengfei Zhang
- Lewis-Sigler Institute for Integrative Genomics, Princeton University, Princeton, NJ 08544, USA; Department of Chemical and Biological Engineering, Princeton University, Princeton, NJ 08544, USA
| | - Adam Boukind
- Department of Molecular Biology, Princeton University, Princeton, NJ 08544, USA
| | - Celeste M Nelson
- Department of Chemical and Biological Engineering, Princeton University, Princeton, NJ 08544, USA; Department of Molecular Biology, Princeton University, Princeton, NJ 08544, USA.
| |
Collapse
|
12
|
Current Understanding of Asthma Pathogenesis and Biomarkers. Cells 2022; 11:cells11172764. [PMID: 36078171 PMCID: PMC9454904 DOI: 10.3390/cells11172764] [Citation(s) in RCA: 72] [Impact Index Per Article: 24.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2022] [Revised: 08/24/2022] [Accepted: 09/01/2022] [Indexed: 11/17/2022] Open
Abstract
Asthma is a heterogeneous lung disease with variable phenotypes (clinical presentations) and distinctive endotypes (mechanisms). Over the last decade, considerable efforts have been made to dissect the cellular and molecular mechanisms of asthma. Aberrant T helper type 2 (Th2) inflammation is the most important pathological process for asthma, which is mediated by Th2 cytokines, such as interleukin (IL)-5, IL-4, and IL-13. Approximately 50% of mild-to-moderate asthma and a large portion of severe asthma is induced by Th2-dependent inflammation. Th2-low asthma can be mediated by non-Th2 cytokines, including IL-17 and tumor necrosis factor-α. There is emerging evidence to demonstrate that inflammation-independent processes also contribute to asthma pathogenesis. Protein kinases, adapter protein, microRNAs, ORMDL3, and gasdermin B are newly identified molecules that drive asthma progression, independent of inflammation. Eosinophils, IgE, fractional exhaled nitric oxide, and periostin are practical biomarkers for Th2-high asthma. Sputum neutrophils are easily used to diagnose Th2-low asthma. Despite progress, more studies are needed to delineate complex endotypes of asthma and to identify new and practical biomarkers for better diagnosis, classification, and treatment.
Collapse
|
13
|
Huang Y, Qiu C. Research advances in airway remodeling in asthma: a narrative review. ANNALS OF TRANSLATIONAL MEDICINE 2022; 10:1023. [PMID: 36267708 PMCID: PMC9577744 DOI: 10.21037/atm-22-2835] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Received: 05/30/2022] [Accepted: 09/06/2022] [Indexed: 12/04/2022]
Abstract
Background and Objective Asthma is a common chronic disorder of the airway, and its disability and mortality rates continue to increase each year. Due to the lack of an ideal treatment, asthma control in China remains unsatisfactory. Airway remodeling is the pathological basis for the eventual development of the fixed airflow limitation in asthmatic patients. Early diagnosis and the prevention of airway remodeling has the potential to decrease disease severity, to improve control, and to prevent disease expression. Methods This article presents an overview. The literature was combed through via CNKi and PubMed according to the listed keywords. We considered Chinese and English original publications (basic science and clinical), reviews and abstracts of 21th Century. Key Content and Findings We review the pathological features and pathogenesis of, and the interventional treatment options for airway remodeling in asthmatic patients, emphasizing the importance of airway remodeling in asthma and providing novel insights into the prevention and control of asthma. Conclusions Thus, there have been research advances in airway remodeling, especially in the areas of slowing down or reversing airway remodeling. As growing studies showed, treating airway remodeling is a promising strategy in preventing the occurrence and progression of asthma. Breakthroughs in these difficulties airway remodeling still facing will open up new avenues in the research and treatment of asthma.
Collapse
Affiliation(s)
- Yanmei Huang
- Department of Respiratory and Critical Care Medicine, The Eighth Affiliated Hospital of Sun Yat-sen University, Shenzhen, China
| | - Chen Qiu
- Department of Respiratory and Critical Care Medicine, Shenzhen People’s Hospital, Shenzhen, China
| |
Collapse
|
14
|
Zhang YL, Zhang RG, Chen FY, Qiu ZE, Chen L, Huang ZX, Huang J, Zhu YX, Zhao L, Zhou WL. Cellular Mechanism Underlying the Facilitation of Contractile Response Induced by Tumor Necrosis Factor-α in Mouse Tracheal Smooth Muscle. THE AMERICAN JOURNAL OF PATHOLOGY 2021; 192:104-111. [PMID: 34756873 DOI: 10.1016/j.ajpath.2021.10.007] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/05/2021] [Revised: 10/08/2021] [Accepted: 10/12/2021] [Indexed: 01/10/2023]
Abstract
The proinflammatory cytokine tumor necrosis factor-α (TNF-α) augments intracellular Ca2+ signaling and contractile responses of airway smooth muscles, leading to airway hyperresponsiveness. However, the underlying mechanism has not been fully elucidated. This study aimed to investigate the cellular mechanism of the potentiated contraction of mouse tracheal smooth muscle induced by TNF-α. The results showed that TNF-α triggered facilitation of mouse tracheal smooth muscle contraction in an epithelium-independent manner. The TNF-α-induced hypercontractility could be suppressed by the protein kinase C inhibitor GF109203X, the tyrosine kinase inhibitor genistein, the Src inhibitor PP2, or the L-type voltage-dependent Ca2+ channel blocker nifedipine. After TNF-α incubation, the α1C L-type Ca2+ channel (CaV1.2) was up-regulated in primary cultured mouse tracheal smooth muscle cells. Pronounced phosphotyrosine levels also were observed in mouse tracheas. In conclusion, this study showed that TNF-α enhanced airway smooth muscle contraction via protein kinase C-Src-CaV1.2 pathways, which provides novel insights into the pathologic role of proinflammatory cytokines in mediating airway hyperresponsiveness.
Collapse
Affiliation(s)
- Yi-Lin Zhang
- School of Life Sciences, Sun Yat-sen University, Guangzhou, China
| | - Rui-Gang Zhang
- School of Life Sciences, Sun Yat-sen University, Guangzhou, China; Department of Physiology, Basic Medical School, Guangdong Medical University, Zhanjiang, China
| | - Feng-Ying Chen
- School of Basic Medical Sciences, Guangzhou Medical University, Guangzhou, China; Department of Pathology, The Maternal and Child Health Care Hospital of HuaDu District (Huzhong Hospital), Guangzhou, China
| | - Zhuo-Er Qiu
- School of Life Sciences, Sun Yat-sen University, Guangzhou, China
| | - Lei Chen
- School of Life Sciences, Sun Yat-sen University, Guangzhou, China
| | - Ze-Xin Huang
- School of Life Sciences, Sun Yat-sen University, Guangzhou, China
| | - Jiehong Huang
- School of Life Sciences, Sun Yat-sen University, Guangzhou, China
| | - Yun-Xin Zhu
- School of Life Sciences, Sun Yat-sen University, Guangzhou, China
| | - Lei Zhao
- School of Basic Medical Sciences, Guangzhou Medical University, Guangzhou, China.
| | - Wen-Liang Zhou
- School of Life Sciences, Sun Yat-sen University, Guangzhou, China.
| |
Collapse
|
15
|
Han YS, Delmotte P, Sieck GC. Effects of TNFα on Dynamic Cytosolic Ca 2 + and Force Responses to Muscarinic Stimulation in Airway Smooth Muscle. Front Physiol 2021; 12:730333. [PMID: 34393833 PMCID: PMC8363307 DOI: 10.3389/fphys.2021.730333] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2021] [Accepted: 07/09/2021] [Indexed: 11/30/2022] Open
Abstract
Previously, we reported that in airway smooth muscle (ASM), the cytosolic Ca2+ ([Ca2+]cyt) and force response induced by acetyl choline (ACh) are increased by exposure to the pro-inflammatory cytokine tumor necrosis factor α (TNFα). The increase in ASM force induced by TNFα was not associated with an increase in regulatory myosin light chain (rMLC20) phosphorylation but was associated with an increase in contractile protein (actin and myosin) concentration and an enhancement of Ca2+ dependent actin polymerization. The sensitivity of ASM force generation to elevated [Ca2+]cyt (Ca2+ sensitivity) is dynamic involving both the shorter-term canonical calmodulin-myosin light chain kinase (MLCK) signaling cascade that regulates rMLC20 phosphorylation and cross-bridge recruitment as well as the longer-term regulation of actin polymerization that regulates contractile unit recruitment and actin tethering to the cortical cytoskeleton. In this study, we simultaneously measured [Ca2+]cyt and force responses to ACh and explored the impact of 24-h TNFα on the dynamic relationship between [Ca2+]cyt and force responses. The temporal delay between the onset of [Ca2+]cyt and force responses was not affected by TNFα. Similarly, the rates of rise of [Ca2+]cyt and force responses were not affected by TNFα. The absence of an impact of TNFα on the short delay relationships between [Ca2+]cyt and force was consistent with the absence of an effect of [Ca2+]cyt and force on rMLC20 phosphorylation. However, the integral of the phase-loop plot of [Ca2+]cyt and force increased with TNFα, consistent with an impact on actin polymerization and, contractile unit recruitment and actin tethering to the cortical cytoskeleton.
Collapse
Affiliation(s)
- Young-Soo Han
- Department of Physiology and Biomedical Engineering, Mayo Clinic, Rochester, MN, United States
| | - Philippe Delmotte
- Department of Physiology and Biomedical Engineering, Mayo Clinic, Rochester, MN, United States
| | - Gary C Sieck
- Department of Physiology and Biomedical Engineering, Mayo Clinic, Rochester, MN, United States
| |
Collapse
|
16
|
Han YS, Delmotte PF, Arteaga GM, Sieck GC. Dynamic cytosolic Ca 2+ and force responses to muscarinic stimulation in airway smooth muscle. Am J Physiol Lung Cell Mol Physiol 2021; 321:L91-L101. [PMID: 33908264 DOI: 10.1152/ajplung.00596.2020] [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: 01/15/2023] Open
Abstract
During agonist stimulation of airway smooth muscle (ASM), agonists such as ACh induce a transient increase in cytosolic Ca2+ concentration ([Ca2+]cyt), which leads to a contractile response [excitation-contraction (E-C) coupling]. Previously, the sensitivity of the contractile response of ASM to elevated [Ca2+]cyt (Ca2+ sensitivity) was assessed as the ratio of maximum force to maximum [Ca2+]cyt. However, this static assessment of Ca2+ sensitivity overlooks the dynamic nature of E-C coupling in ASM. In this study, we simultaneously measured [Ca2+]cyt and isometric force responses to three concentrations of ACh (1, 2.6, and 10 μM). Both maximum [Ca2+]cyt and maximum force responses were ACh concentration dependent, but force increased disproportionately, thereby increasing static Ca2+ sensitivity. The dynamic properties of E-C coupling were assessed in several ways. The temporal delay between the onset of ACh-induced [Ca2+]cyt and onset force responses was not affected by ACh concentration. The rates of rise of the ACh-induced [Ca2+]cyt and force responses increased with increasing ACh concentration. The integral of the phase-loop plot of [Ca2+]cyt and force from onset to steady state also increased with increasing ACh concentration, whereas the rate of relaxation remained unchanged. Although these results suggest an ACh concentration-dependent increase in the rate of cross-bridge recruitment and in the rate of rise of [Ca2+]cyt, the extent of regulatory myosin light-chain (rMLC20) phosphorylation was not dependent on ACh concentration. We conclude that the dynamic properties of [Ca2+]cyt and force responses in ASM are dependent on ACh concentration but reflect more than changes in the extent of rMLC20 phosphorylation.
Collapse
Affiliation(s)
- Young-Soo Han
- Department of Physiology and Biomedical Engineering, Mayo Clinic, Rochester, Minnesota
| | - Philippe F Delmotte
- Department of Physiology and Biomedical Engineering, Mayo Clinic, Rochester, Minnesota
| | - Grace M Arteaga
- Department of Physiology and Biomedical Engineering, Mayo Clinic, Rochester, Minnesota
| | - Gary C Sieck
- Department of Physiology and Biomedical Engineering, Mayo Clinic, Rochester, Minnesota
| |
Collapse
|
17
|
Delmotte P, Marin Mathieu N, Sieck GC. TNFα induces mitochondrial fragmentation and biogenesis in human airway smooth muscle. Am J Physiol Lung Cell Mol Physiol 2021; 320:L137-L151. [PMID: 33146568 PMCID: PMC7847063 DOI: 10.1152/ajplung.00305.2020] [Citation(s) in RCA: 26] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2020] [Revised: 10/06/2020] [Accepted: 10/29/2020] [Indexed: 12/16/2022] Open
Abstract
In human airway smooth muscle (hASM), mitochondrial volume density is greater in asthmatic patients compared with normal controls. There is also an increase in mitochondrial fragmentation in hASM of moderate asthmatics associated with an increase in dynamin-related protein 1 (Drp1) and a decrease in mitofusin 2 (Mfn2) expression, mitochondrial fission, and fusion proteins, respectively. Proinflammatory cytokines such TNFα contribute to hASM hyperreactivity and cell proliferation associated with asthma. However, the involvement of proinflammatory cytokines in mitochondrial remodeling is not clearly established. In nonasthmatic hASM cells, mitochondria were labeled using MitoTracker Red and imaged in three dimensions using a confocal microscope. After 24-h TNFα exposure, mitochondria in hASM cells were more fragmented, evidenced by decreased form factor and aspect ratio and increased sphericity. Associated with increased mitochondrial fragmentation, Drp1 expression increased while Mfn2 expression was reduced. TNFα also increased mitochondrial biogenesis in hASM cells reflected by increased peroxisome proliferator-activated receptor-γ coactivator 1α expression and increased mitochondrial DNA copy number. Associated with mitochondrial biogenesis, TNFα exposure also increased mitochondrial volume density and porin expression, resulting in an increase in maximum O2 consumption rate. However, when normalized for mitochondrial volume density, O2 consumption rate per mitochondrion was reduced by TNFα exposure. Associated with mitochondrial fragmentation and biogenesis, TNFα also increased hASM cell proliferation, an effect mimicked by siRNA knockdown of Mfn2 expression and mitigated by Mfn2 overexpression. The results of this study support our hypothesis that in hASM cells exposed to TNFα mitochondria are more fragmented, with an increase in mitochondrial biogenesis and mitochondrial volume density resulting in reduced O2 consumption rate per mitochondrion.
Collapse
Affiliation(s)
- Philippe Delmotte
- Department of Physiology and Biomedical Engineering, Mayo Clinic, Rochester, Minnesota
| | - Natalia Marin Mathieu
- Department of Physiology and Biomedical Engineering, Mayo Clinic, Rochester, Minnesota
| | - Gary C Sieck
- Department of Physiology and Biomedical Engineering, Mayo Clinic, Rochester, Minnesota
| |
Collapse
|
18
|
Inflammation-Induced Protein Unfolding in Airway Smooth Muscle Triggers a Homeostatic Response in Mitochondria. Int J Mol Sci 2020; 22:ijms22010363. [PMID: 33396378 PMCID: PMC7795579 DOI: 10.3390/ijms22010363] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2020] [Revised: 12/17/2020] [Accepted: 12/28/2020] [Indexed: 12/11/2022] Open
Abstract
The effects of airway inflammation on airway smooth muscle (ASM) are mediated by pro-inflammatory cytokines such as tumor necrosis factor alpha (TNFα). In this review article, we will provide a unifying hypothesis for a homeostatic response to airway inflammation that mitigates oxidative stress and thereby provides resilience to ASM. Previous studies have shown that acute exposure to TNFα increases ASM force generation in response to muscarinic stimulation (hyper-reactivity) resulting in increased ATP consumption and increased tension cost. To meet this increased energetic demand, mitochondrial O2 consumption and oxidative phosphorylation increases but at the cost of increased reactive oxygen species (ROS) production (oxidative stress). TNFα-induced oxidative stress results in the accumulation of unfolded proteins in the endoplasmic reticulum (ER) and mitochondria of ASM. In the ER, TNFα selectively phosphorylates inositol-requiring enzyme 1 alpha (pIRE1α) triggering downstream splicing of the transcription factor X-box binding protein 1 (XBP1s); thus, activating the pIRE1α/XBP1s ER stress pathway. Protein unfolding in mitochondria also triggers an unfolded protein response (mtUPR). In our conceptual framework, we hypothesize that activation of these pathways is homeostatically directed towards mitochondrial remodeling via an increase in peroxisome proliferator-activated receptor-gamma coactivator 1 alpha (PGC1α) expression, which in turn triggers: (1) mitochondrial fragmentation (increased dynamin-related protein-1 (Drp1) and reduced mitofusin-2 (Mfn2) expression) and mitophagy (activation of the Phosphatase and tensin homolog (PTEN)-induced putative kinase 1 (PINK1)/Parkin mitophagy pathway) to improve mitochondrial quality; (2) reduced Mfn2 also results in a disruption of mitochondrial tethering to the ER and reduced mitochondrial Ca2+ influx; and (3) mitochondrial biogenesis and increased mitochondrial volume density. The homeostatic remodeling of mitochondria results in more efficient O2 consumption and oxidative phosphorylation and reduced ROS formation by individual mitochondrion, while still meeting the increased ATP demand. Thus, the energetic load of hyper-reactivity is shared across the mitochondrial pool within ASM cells.
Collapse
|
19
|
Delmotte P, Han Y, Sieck GC. Cytoskeletal remodeling slows cross-bridge cycling and ATP hydrolysis rates in airway smooth muscle. Physiol Rep 2020; 8:e14561. [PMID: 32812390 PMCID: PMC7435030 DOI: 10.14814/phy2.14561] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2020] [Revised: 08/03/2020] [Accepted: 08/05/2020] [Indexed: 12/14/2022] Open
Abstract
During isometric activation of airway smooth muscle (ASM), cross-bridge cycling and ATP hydrolysis rates decline across time even though isometric force is sustained. Thus, tension cost (i.e., ATP hydrolysis rate per unit of force during activation) decreases with time. The "latch-state" hypothesis attributes the dynamic change in cross-bridge cycling and ATP hydrolysis rates to changes in phosphorylation of the regulatory myosin light chain (rMLC20 ). However, we previously showed that in ASM, the extent of rMLC20 phosphorylation remains unchanged during sustained isometric force. As an alternative, we hypothesized that cytoskeletal remodeling within ASM cells results in increased internal loading of contractile proteins that slows cross-bridge cycling and ATP hydrolysis rates. To test this hypothesis, we simultaneously measured isometric force and ATP hydrolysis rate in permeabilized porcine ASM strips activated by Ca2+ (pCa 4.0). The extent of rMLC20 phosphorylation remained unchanged during isometric activation, even though ATP hydrolysis rate (tension cost) declined with time. The effect of cytoskeletal remodeling was assessed by inhibiting actin polymerization using Cytochalasin D (Cyto-D). In Cyto-D treated ASM, isometric force was reduced while ATP hydrolysis rate increased compared to untreated ASM strips. These results indicate that external transmission of force, cross-bridge cycling and ATP hydrolysis rates are affected by internal loading of contractile proteins.
Collapse
Affiliation(s)
- Philippe Delmotte
- Department of Physiology and Biomedical EngineeringMayo ClinicRochesterMNUSA
| | - Young‐soo Han
- Department of Physiology and Biomedical EngineeringMayo ClinicRochesterMNUSA
| | - Gary C. Sieck
- Department of Physiology and Biomedical EngineeringMayo ClinicRochesterMNUSA
| |
Collapse
|
20
|
Álvarez-Santos MD, Álvarez-González M, Estrada-Soto S, Bazán-Perkins B. Regulation of Myosin Light-Chain Phosphatase Activity to Generate Airway Smooth Muscle Hypercontractility. Front Physiol 2020; 11:701. [PMID: 32676037 PMCID: PMC7333668 DOI: 10.3389/fphys.2020.00701] [Citation(s) in RCA: 31] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2019] [Accepted: 05/28/2020] [Indexed: 12/21/2022] Open
Abstract
Smooth muscle is a central structure involved in the regulation of airway tone. In addition, it plays an important role in the development of some pathologies generated by alterations in contraction, such as hypercontractility and the airway hyperresponsiveness observed in asthma. The molecular processes associated with smooth muscle contraction are centered around myosin light chain (MLC) phosphorylation, which is controlled by a balance in the activity of myosin light-chain kinase (MLCK) and myosin light-chain phosphatase (MLCP). MLCK activation depends on increasing concentrations of intracellular Ca2+, while MLCP activation is independent of Ca2+. MLCP contains a phosphatase subunit (PP1c) that is regulated through myosin phosphatase target subunit 1 (MYPT1) and other subunits, such as glycogen-associated regulatory subunit and myosin-binding subunit 85 kDa. Interestingly, MLCP inhibition may contribute to exacerbation of smooth muscle contraction by increasing MLC phosphorylation to induce hypercontractility. Many pathways inhibiting MLCP activity in airway smooth muscle have been proposed and are focused on inhibition of PP1c, inhibitory phosphorylation of MYPT1 and dissociation of the PP1c-MYPT1 complex.
Collapse
Affiliation(s)
- Mayra D Álvarez-Santos
- Biology Area, Facultad de Ciencias, Universidad Nacional Autónoma de México, Mexico City, Mexico
| | - Marisol Álvarez-González
- Laboratorio de Inmunofarmacología, Instituto Nacional de Enfermedades Respiratorias "Ismael Cosío Villegas", Mexico City, Mexico
| | - Samuel Estrada-Soto
- Facultad de Farmacia, Universidad Autónoma del Estado de Morelos, Cuernavaca, Mexico
| | - Blanca Bazán-Perkins
- Laboratorio de Inmunofarmacología, Instituto Nacional de Enfermedades Respiratorias "Ismael Cosío Villegas", Mexico City, Mexico.,Tecnológico de Monterrey, Escuela de Medicina y Ciencias de la Salud, Monterrey, Mexico
| |
Collapse
|
21
|
Delmotte P, Sieck GC. Endoplasmic Reticulum Stress and Mitochondrial Function in Airway Smooth Muscle. Front Cell Dev Biol 2020; 7:374. [PMID: 32010691 PMCID: PMC6974519 DOI: 10.3389/fcell.2019.00374] [Citation(s) in RCA: 38] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2019] [Accepted: 12/16/2019] [Indexed: 12/16/2022] Open
Abstract
Inflammatory airway diseases such as asthma affect more than 300 million people world-wide. Inflammation triggers pathophysiology via such as tumor necrosis factor α (TNFα) and interleukins (e.g., IL-13). Hypercontraction of airway smooth muscle (ASM) and ASM cell proliferation are major contributors to the exaggerated airway narrowing that occurs during agonist stimulation. An emergent theme in this context is the role of inflammation-induced endoplasmic reticulum (ER) stress and altered mitochondrial function including an increase in the formation of reactive oxygen species (ROS). This may establish a vicious cycle as excess ROS generation leads to further ER stress. Yet, it is unclear whether inflammation-induced ROS is the major mechanism leading to ER stress or the consequence of ER stress. In various diseases, inflammation leads to an increase in mitochondrial fission (fragmentation), associated with reduced levels of mitochondrial fusion proteins, such as mitofusin 2 (Mfn2). Mitochondrial fragmentation may be a homeostatic response since it is generally coupled with mitochondrial biogenesis and mitochondrial volume density thereby reducing demand on individual mitochondrion. ER stress is triggered by the accumulation of unfolded proteins, which induces a homeostatic response to alter protein balance via effects on protein synthesis and degradation. In addition, the ER stress response promotes protein folding via increased expression of molecular chaperone proteins. Reduced Mfn2 and altered mitochondrial dynamics may not only be downstream to ER stress but also upstream such that a reduction in Mfn2 triggers further ER stress. In this review, we summarize the current understanding of the link between inflammation-induced ER stress and mitochondrial function and the role played in the pathophysiology of inflammatory airway diseases.
Collapse
Affiliation(s)
- Philippe Delmotte
- Department of Physiology and Biomedical Engineering, Mayo Clinic, Rochester, MN, United States
| | - Gary C Sieck
- Department of Physiology and Biomedical Engineering, Mayo Clinic, Rochester, MN, United States
| |
Collapse
|