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Hu R, Wu F, Zheng YQ. Ivacaftor attenuates gentamicin-induced ototoxicity through the CFTR-Nrf2-HO1/NQO1 pathway. Redox Rep 2024; 29:2332038. [PMID: 38563333 PMCID: PMC10993751 DOI: 10.1080/13510002.2024.2332038] [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] [Indexed: 04/04/2024] Open
Abstract
OBJECTIVES Gentamicin is one of the most common ototoxic drugs that can lower patients' quality of life. Oxidative stress is a key factors inducing sensory hair cell death during gentamicin administration. So far, there are no effective drugs to prevent or treat gentamicin- induced hearing loss. A recent study found cystic fibrosis transmembrane conductance regulator (CFTR) as a new target to modulate cellular oxidative balance. The objective of this study was to estimate the effect of the CFTR activator ivacaftor on gentamicin-induced ototoxicity and determine its mechanism. METHODS The hair cell count was analyzed by Myosin 7a staining. Apoptosis was analyzed by TUNEL Apoptosis Kit. Cellular reactive oxygen species (ROS) level was detected by DCFH-DA probes. The Nrf2 related proteins expression levels were analyzed by western blot. RESULTS An in vitro cochlear explant model showed that gentamicin caused ROS accumulation in sensory hair cells and induced apoptosis, and this effect was alleviated by pretreatment with ivacaftor. Western blotting showed that ivacaftor administration markedly increased the protein expression of nuclear factor erythroid 2-related factor 2 (Nrf2), heme oxygenase-1 (HO1), and NAD(P)H:quinone oxidoreductase 1 (NQO1). The protective effect of ivacaftor was abolished by the Nrf2 inhibitor ML385. DISCUSSION Our results indicate the protective role of the CFTR-Nrf2-HO1/NQO1 pathway in gentamicin-induced ototoxicity. Ivacaftor may be repositioned or repurposed towards aminoglycosides-induced hearing loss.
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Affiliation(s)
- Rui Hu
- Shenshan Medical Center, Memorial Hospital of Sun Yat-Sen University, Shanwei, People’s Republic of China
- Department of Otolaryngology, Sun Yat-Sen Memorial Hospital, Sun Yat-Sen University, Guangzhou, People’s Republic of China
| | - Fan Wu
- Department of Otolaryngology, Sun Yat-Sen Memorial Hospital, Sun Yat-Sen University, Guangzhou, People’s Republic of China
- Guangdong Provincial Key Laboratory of Malignant Tumor Epigenetics and Gene Regulation, Sun Yat-sen Memorial Hospital, Sun Yat-sen University, Guangzhou, People’s Republic of China
- Department of Pathology and Laboratory Medicine, The Medical University of South Carolina, Charleston, SC, USA
| | - Yi-Qing Zheng
- Shenshan Medical Center, Memorial Hospital of Sun Yat-Sen University, Shanwei, People’s Republic of China
- Department of Otolaryngology, Sun Yat-Sen Memorial Hospital, Sun Yat-Sen University, Guangzhou, People’s Republic of China
- Guangdong Provincial Key Laboratory of Malignant Tumor Epigenetics and Gene Regulation, Sun Yat-sen Memorial Hospital, Sun Yat-sen University, Guangzhou, People’s Republic of China
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2
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Yang D, Wu M, Zou N, Tang Y, Tao Q, Liu L, Jin M, Yu L, Du J, Luo Q, Shen J, Chu D, Qin K. Knockdown of DJ-1 Exacerbates Neuron Apoptosis Induced by TgCtwh3 through the NF-κB Pathway. Mol Neurobiol 2024:10.1007/s12035-024-04265-7. [PMID: 38831169 DOI: 10.1007/s12035-024-04265-7] [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: 01/17/2024] [Accepted: 05/25/2024] [Indexed: 06/05/2024]
Abstract
Mutations or loss of function of DJ-1 and Toxoplasma gondii (T. gondii) infection has been linked to neurodegenerative diseases, which are often caused by oxidative stress. However, the relationship between DJ-1 and T. gondii infection is not yet fully understood. Therefore, this study aimed to investigate the expression of DJ-1 in the hippocampus tissue of mice or in HT22 infected with T. gondii Chinese 1 genotype Wh3 strain (TgCtwh3) and the effect of DJ-1 knockdown on neuronal apoptosis induced by TgCtwh3 tachyzoite, as well as the underlying mechanism at the cellular and molecular level. Firstly, we detected DJ-1 protein expression and cell apoptosis in the hippocampal tissue of mice infected by TgCtwh3. Then, we examined DJ-1 expression and apoptosis in HT22 challenged with TgCtwh3. Finally, we evaluated the apoptosis in HT22 with DJ-1 knockdown which was infected with TgCtwh3 and assayed the expression of NF-κBp65 and p-NF-κBp65. Our results showed that DJ-1 expression was reduced and neurons underwent apoptosis in the hippocampus of mice infected with TgCtwh3 tachyzoites. Additionally, the knockdown of DJ-1 followed by infection with TgCtwh3 tachyzoites led to increased apoptosis in HT22 cells through the NF-κB signaling pathway. Therefore, this study suggests that DJ-1 is an important target for preventing apoptosis caused by T. gondii TgCtwh3.
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Affiliation(s)
- Di Yang
- Department of Pathogen Biology, Anhui Province Key Laboratory of Microbiology & Parasitology, Anhui Provincial Laboratory of Zoonoses of High Institutions, School of Basic Medicine, Anhui Medical University, Hefei, China
| | - Minmin Wu
- Department of Clinical Laboratory, The First Affiliated Hospital of Anhui Medical University, Hefei, China
| | - Nian Zou
- Second School of Clinical Medicine, Anhui Medical University, Hefei, China
| | - Yiru Tang
- School of Public Health, Anhui Medical University, Hefei, China
| | - Qing Tao
- Center for Translational Medicine, Jiangsu Key Laboratory of Molecular Medicine, Medical School of Nanjing University, Nanjing, China
| | - Lei Liu
- Department of Blood Transfusion, Division of Life Sciences and Medicine, the First Affiliated Hospital of USTC, University of Science and Technology of China, Hefei, China
| | - Mengmeng Jin
- Maternity and Child Health Hospital of Anhui Province, the Affiliated Maternity and Child Health Hospital of Anhui Medical University, Hefei, China
| | - Li Yu
- Department of Microbiology and Parasitology, Anhui Provincial Laboratory of Microbiology and Parasitology, Anhui Provincial Laboratory of Zoonoses of High Institutions, School of Basic Medical Sciences, Anhui Medical University, Hefei, China
| | - Jian Du
- Department of Biochemistry and Molecular Biology, School of Basic Medical Sciences, Anhui Medical University, Hefei, China
| | - Qingli Luo
- Department of Pathogen Biology, Anhui Province Key Laboratory of Microbiology & Parasitology, Anhui Provincial Laboratory of Zoonoses of High Institutions, School of Basic Medicine, Anhui Medical University, Hefei, China
| | - Jilong Shen
- Department of Pathogen Biology, Anhui Province Key Laboratory of Microbiology & Parasitology, Anhui Provincial Laboratory of Zoonoses of High Institutions, School of Basic Medicine, Anhui Medical University, Hefei, China
| | - Deyong Chu
- Department of Pathogen Biology, Anhui Province Key Laboratory of Microbiology & Parasitology, Anhui Provincial Laboratory of Zoonoses of High Institutions, School of Basic Medicine, Anhui Medical University, Hefei, China.
| | - Kunpeng Qin
- Department of Orthopaedics, The First Affiliated Hospital of Anhui Medical University, Hefei, China.
- Department of Orthopaedics, Anhui Public Health Clinical Center, Hefei, Anhui, China.
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3
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Tao Q, Yang D, Qin K, Liu L, Jin M, Zhang F, Zhu J, Wang J, Luo Q, Du J, Yu L, Shen J, Chu D. Studies on the mechanism of Toxoplasma gondii Chinese 1 genotype Wh6 strain causing mice abnormal cognitive behavior. Parasit Vectors 2023; 16:30. [PMID: 36698166 PMCID: PMC9875435 DOI: 10.1186/s13071-022-05618-8] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2022] [Accepted: 12/14/2022] [Indexed: 01/26/2023] Open
Abstract
BACKGROUND Alzheimer's disease presents an abnormal cognitive behavior. TgCtwh6 is one of the predominant T. gondii strains prevalent in China. Although T. gondii type II strain infection can cause host cognitive behavioral abnormalities, we do not know whether TgCtwh6 could also cause host cognitive behavioral changes. So, in this study, we will focus on the effect of TgCtwh6 on mouse cognitive behavior and try in vivo and in vitro to explore the underlying mechanism by which TgCtwh6 give rise to mice cognitive behavior changes at the cellular and molecular level. METHODS C57BL/6 mice were infected orally with TgCtwh6 cysts. From day 90 post-infection on, all mice were conducted through the open field test and then Morris water maze test to evaluate cognitive behavior. The morphology and number of cells in hippocampus were examined with hematoxylin-eosin (H&E) and Nissl staining; moreover, Aβ protein in hippocampus was determined with immunohistochemistry and thioflavin S plaque staining. Synaptotagmin 1, apoptosis-related proteins, BACE1 and APP proteins and genes from hippocampus were assessed by western blotting or qRT-PCR. Hippocampal neuronal cell line or mouse microglial cell line was challenged with TgCtwh6 tachyzoites and then separately cultured in a well or co-cultured in a transwell device. The target proteins and genes were analyzed by immunofluorescence staining, western blotting and qRT-PCR. In addition, mouse microglial cell line polarization state and hippocampal neuronal cell line apoptosis were estimated using flow cytometry assay. RESULTS The OFT and MWMT indicated that infected mice had cognitive behavioral impairments. The hippocampal tissue assay showed abnormal neuron morphology and a decreased number in infected mice. Moreover, pro-apoptotic proteins, as well as BACE1, APP and Aβ proteins, increased in the infected mouse hippocampus. The experiments in vitro showed that pro-apoptotic proteins and p-NF-κBp65, NF-κBp65, BACE1, APP and Aβ proteins or genes were significantly increased in the infected HT22. In addition, CD80, pro-inflammatory factors, notch, hes1 proteins and genes were enhanced in the infected BV2. Interestingly, not only the APP and pro-apoptotic proteins in HT22, but also the apoptosis rate of HT22 increased after the infected BV2 were co-cultured with the HT22 in a transwell device. CONCLUSIONS Neuron apoptosis, Aβ deposition and neuroinflammatory response involved with microglia polarization are the molecular and cellular mechanisms by which TgCtwh6 causes mouse cognitive behavioral abnormalities.
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Affiliation(s)
- Qing Tao
- grid.186775.a0000 0000 9490 772XDepartment of Pathogen Biology, Anhui Province Key Laboratory of Microbiology & Parasitology, Anhui Provincial Laboratory of Zoonoses of High Institutions, School of Basic Medicine, Anhui Medical University, Hefei, China
| | - Di Yang
- grid.186775.a0000 0000 9490 772XDepartment of Pathogen Biology, Anhui Province Key Laboratory of Microbiology & Parasitology, Anhui Provincial Laboratory of Zoonoses of High Institutions, School of Basic Medicine, Anhui Medical University, Hefei, China
| | - Kunpeng Qin
- grid.412679.f0000 0004 1771 3402Department of Orthopaedics, the First Affiliated Hospital of Anhui Medical University, Anhui, China
| | - Lei Liu
- grid.59053.3a0000000121679639Department of Blood Transfusion, Division of Life Sciences and Medicine, The First Affiliated Hospital of USTC, University of Science and Technology of China, Hefei, China
| | - Mengmeng Jin
- grid.186775.a0000 0000 9490 772XMaternity and Child Health Hospital of Anhui Province, The Affiliated Maternity and Child Health Hospital of Anhui Medical University, Hefei, China
| | - Famin Zhang
- grid.186775.a0000 0000 9490 772XDepartment of Biochemistry and Molecular Biology, School of Basic Medical Sciences, Anhui Medical University, Hefei, China
| | - Jinjin Zhu
- grid.186775.a0000 0000 9490 772XDepartment of Biochemistry and Molecular Biology, School of Basic Medical Sciences, Anhui Medical University, Hefei, China
| | - Jie Wang
- grid.186775.a0000 0000 9490 772XDepartment of Microbiology and Parasitology, Anhui Provincial Laboratory of Microbiology and Parasitology, Anhui Provincial Laboratory of Zoonoses of High Institutions, School of Basic Medical Sciences, Anhui Medical University, Hefei, China
| | - Qingli Luo
- grid.186775.a0000 0000 9490 772XDepartment of Pathogen Biology, Anhui Province Key Laboratory of Microbiology & Parasitology, Anhui Provincial Laboratory of Zoonoses of High Institutions, School of Basic Medicine, Anhui Medical University, Hefei, China
| | - Jian Du
- grid.186775.a0000 0000 9490 772XDepartment of Microbiology and Parasitology, Anhui Provincial Laboratory of Microbiology and Parasitology, Anhui Provincial Laboratory of Zoonoses of High Institutions, School of Basic Medical Sciences, Anhui Medical University, Hefei, China
| | - Li Yu
- grid.186775.a0000 0000 9490 772XDepartment of Biochemistry and Molecular Biology, School of Basic Medical Sciences, Anhui Medical University, Hefei, China
| | - Jilong Shen
- grid.186775.a0000 0000 9490 772XDepartment of Pathogen Biology, Anhui Province Key Laboratory of Microbiology & Parasitology, Anhui Provincial Laboratory of Zoonoses of High Institutions, School of Basic Medicine, Anhui Medical University, Hefei, China
| | - Deyong Chu
- grid.186775.a0000 0000 9490 772XDepartment of Pathogen Biology, Anhui Province Key Laboratory of Microbiology & Parasitology, Anhui Provincial Laboratory of Zoonoses of High Institutions, School of Basic Medicine, Anhui Medical University, Hefei, China
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4
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Caverly LJ, Riquelme SA, Hisert KB. The Impact of Highly Effective Modulator Therapy on Cystic Fibrosis Microbiology and Inflammation. Clin Chest Med 2022; 43:647-665. [PMID: 36344072 PMCID: PMC10224747 DOI: 10.1016/j.ccm.2022.06.007] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
Highly effective cystic fibrosis (CF) transmembrane conductance regulator (CFTR) modulator therapy (HEMT) corrects the underlying molecular defect causing CF disease. HEMT decreases symptom burden and improves clinical metrics and quality of life for most people with CF (PwCF) and eligible cftr mutations. Improvements in measures of pulmonary health suggest that restoration of function of defective CFTR anion channels by HEMT not only enhances airway mucociliary clearance, but also reduces chronic pulmonary infection and inflammation. This article reviews the evidence for how HEMT influences the dynamic and interdependent processes of infection and inflammation in the CF airway, and what questions remain unanswered.
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Affiliation(s)
- Lindsay J Caverly
- Department of Pediatrics, University of Michigan Medical School, L2221 UH South, 1500 East Medical Center Drive, Ann Arbor, MI 48109-5212, USA
| | - Sebastián A Riquelme
- Department of Pediatrics, College of Physicians and Surgeons, Columbia University, Columbia University Medical Center, 650West 168th Street, New York, NY 10032, USA
| | - Katherine B Hisert
- Department of Medicine, National Jewish Health, Smith A550, 1400 Jackson Street, Denver, CO 80205, USA.
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5
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Causer AJ, Shute JK, Cummings MH, Shepherd AI, Wallbanks SR, Pulsford RM, Bright V, Connett G, Saynor ZL. Elexacaftor-Tezacaftor-Ivacaftor improves exercise capacity in adolescents with cystic fibrosis. Pediatr Pulmonol 2022; 57:2652-2658. [PMID: 35851858 PMCID: PMC9795914 DOI: 10.1002/ppul.26078] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/11/2022] [Revised: 06/14/2022] [Accepted: 06/25/2022] [Indexed: 12/30/2022]
Abstract
OBJECTIVE Elexacaftor/Tezacaftor/Ivacaftor is a cystic fibrosis transmembrane conductance regulator (CFTR) modulator with the potential to improve exercise capacity. This case series of three adolescents with CF aimed to investigate whether 6 weeks treatment with Elexacaftor/Tezacaftor/Ivacaftor could improve exercise capacity in CFTR modulator naive adolescents with CF. METHODS Three adolescents (14.0 ± 1.4 years) with CF (FEV1 % predicted: 62.5 ± 17.1; F508del/F508del genotype) completed an exhaustive maximal cardiopulmonary exercise test on a cycle ergometer to determine peak oxygen uptake ( <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:semantics> <mml:mrow><mml:mover><mml:mi>V</mml:mi> <mml:mo>̇</mml:mo></mml:mover> </mml:mrow> <mml:annotation>$\dot{{\rm{V}}}$</mml:annotation></mml:semantics> </mml:math> O2peak ) and measure changes in gas exchange and ventilation during exercise at 6 weeks. We also analyzed wrist-worn device-based physical activity (PA) data in two of the three cases. Validated acceleration thresholds were used to quantify time spent in each PA intensity category. RESULTS Clinically meaningful improvements in <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:semantics> <mml:mrow><mml:mover><mml:mi>V</mml:mi> <mml:mo>̇</mml:mo></mml:mover> </mml:mrow> <mml:annotation>$\dot{{\rm{V}}}$</mml:annotation></mml:semantics> </mml:math> O2peak were observed in all three cases (+17.6%, +52.4%, and +32.9%, respectively), with improvements greatest in those with more severe lung disease and lower fitness at baseline. Although lung function increased in all cases, inconsistent changes in markers of ventilatory and peripheral muscle efficiency likely suggest different mechanisms of improvement in this case group of adolescents with CF. Device-based analysis of PA was variable, with one case increasing and one case decreasing. CONCLUSION In this case series, we have observed, for the first time, improvements in exercise capacity following 6 weeks of treatment with Elexacaftor/Tezacaftor/Ivacaftor. Improvements were greatest in the presence of more severe CF lung disease and lower aerobic fitness at baseline. The mechanism(s) responsible for these changes warrant further investigation in larger trials.
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Affiliation(s)
- Adam J Causer
- School of Sport, Health and Exercise Science, Faculty of Science and Health, University of Portsmouth, Portsmouth, UK.,Cystic Fibrosis Unit, University Hospital Southampton NHS Foundation Trust, Southampton, UK
| | - Janis K Shute
- School of Pharmacy and Biomedical Sciences, Faculty of Science and Health, University of Portsmouth, Portsmouth, UK
| | - Michael H Cummings
- Department of Diabetes and Endocrinology, Queen Alexandra Hospital, Portsmouth, UK
| | - Anthony I Shepherd
- School of Sport, Health and Exercise Science, Faculty of Science and Health, University of Portsmouth, Portsmouth, UK
| | - Samuel R Wallbanks
- School of Sport, Health and Exercise Science, Faculty of Science and Health, University of Portsmouth, Portsmouth, UK
| | - Richard M Pulsford
- Sport and Health Sciences, College of Life and Environmental Science, University of Exeter, Exeter, UK
| | - Victoria Bright
- Cystic Fibrosis Unit, University Hospital Southampton NHS Foundation Trust, Southampton, UK
| | - Gary Connett
- Cystic Fibrosis Unit, University Hospital Southampton NHS Foundation Trust, Southampton, UK.,National Institute for Health Research, Southampton Biomedical Research Centre, Southampton Children's Hospital, Southampton, UK
| | - Zoe L Saynor
- School of Sport, Health and Exercise Science, Faculty of Science and Health, University of Portsmouth, Portsmouth, UK.,Cystic Fibrosis Unit, University Hospital Southampton NHS Foundation Trust, Southampton, UK
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6
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Bhattacharya R, Blankenheim Z, Scott PM, Cormier RT. CFTR and Gastrointestinal Cancers: An Update. J Pers Med 2022; 12:868. [PMID: 35743652 PMCID: PMC9224611 DOI: 10.3390/jpm12060868] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2022] [Revised: 05/21/2022] [Accepted: 05/23/2022] [Indexed: 11/17/2022] Open
Abstract
Cystic Fibrosis (CF) is a disease caused by mutations in the CFTR gene that severely affects the lungs as well as extra-pulmonary tissues, including the gastrointestinal (GI) tract. CFTR dysfunction resulting from either mutations or the downregulation of its expression has been shown to promote carcinogenesis. An example is the enhanced risk for several types of cancer in patients with CF, especially cancers of the GI tract. CFTR also acts as a tumor suppressor in diverse sporadic epithelial cancers in many tissues, primarily due to the silencing of CFTR expression via multiple mechanisms, but especially due to epigenetic regulation. This review provides an update on the latest research linking CFTR-deficiency to GI cancers, in both CF patients and in sporadic GI cancers, with a particular focus on cancer of the intestinal tract. It will discuss changes in the tissue landscape linked to CFTR-deficiency that may promote cancer development such as breakdowns in physical barriers, microbial dysbiosis and inflammation. It will also discuss molecular pathways and mechanisms that act upstream to modulate CFTR expression, such as by epigenetic silencing, as well as molecular pathways that act downstream of CFTR-deficiency, such as the dysregulation of the Wnt/β-catenin and NF-κB signaling pathways. Finally, it will discuss the emerging CFTR modulator drugs that have shown promising results in improving CFTR function in CF patients. The potential impact of these modulator drugs on the treatment and prevention of GI cancers can provide a new example of personalized cancer medicine.
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Affiliation(s)
| | | | - Patricia M. Scott
- Department of Biomedical Sciences, University of Minnesota Medical School, Duluth, MN 55812, USA or (R.B.); (Z.B.)
| | - Robert T. Cormier
- Department of Biomedical Sciences, University of Minnesota Medical School, Duluth, MN 55812, USA or (R.B.); (Z.B.)
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7
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Cystic fibrosis-related liver disease: Clinical presentations, diagnostic and monitoring approaches in the era of CFTR modulator therapies. J Hepatol 2022; 76:420-434. [PMID: 34678405 DOI: 10.1016/j.jhep.2021.09.042] [Citation(s) in RCA: 37] [Impact Index Per Article: 18.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/08/2021] [Revised: 09/09/2021] [Accepted: 09/30/2021] [Indexed: 12/11/2022]
Abstract
Cystic fibrosis (CF) is the most common autosomal recessive disease in the Caucasian population. Cystic fibrosis-related liver disease (CFLD) is defined as the pathogenesis related to the underlying CFTR defect in biliary epithelial cells. CFLD needs to be distinguished from other liver manifestations that may not have any pathological significance. The clinical/histological presentation and severity of CFLD vary. The main histological presentation of CFLD is focal biliary fibrosis, which is usually asymptomatic. Portal hypertension develops in a minority of cases (about 10%) and may require specific management including liver transplantation for end-stage liver disease. Portal hypertension is usually the result of the progression of focal biliary fibrosis to multilobular cirrhosis during childhood. Nevertheless, non-cirrhotic portal hypertension as a result of porto-sinusoidal vascular disease is now identified increasingly more frequently, mainly in young adults. To evaluate the effect of new CFTR modulator therapies on the liver, the spectrum of hepatobiliary involvement must first be precisely classified. This paper discusses the phenotypic features of CFLD, its underlying physiopathology and relevant diagnostic and follow-up approaches, with a special focus on imaging.
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8
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Tretter V, Hochreiter B, Zach ML, Krenn K, Klein KU. Understanding Cellular Redox Homeostasis: A Challenge for Precision Medicine. Int J Mol Sci 2021; 23:ijms23010106. [PMID: 35008532 PMCID: PMC8745322 DOI: 10.3390/ijms23010106] [Citation(s) in RCA: 44] [Impact Index Per Article: 14.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2021] [Revised: 12/20/2021] [Accepted: 12/21/2021] [Indexed: 12/16/2022] Open
Abstract
Living organisms use a large repertoire of anabolic and catabolic reactions to maintain their physiological body functions, many of which include oxidation and reduction of substrates. The scientific field of redox biology tries to understand how redox homeostasis is regulated and maintained and which mechanisms are derailed in diverse pathological developments of diseases, where oxidative or reductive stress is an issue. The term “oxidative stress” is defined as an imbalance between the generation of oxidants and the local antioxidative defense. Key mediators of oxidative stress are reactive species derived from oxygen, nitrogen, and sulfur that are signal factors at physiological concentrations but can damage cellular macromolecules when they accumulate. However, therapeutical targeting of oxidative stress in disease has proven more difficult than previously expected. Major reasons for this are the very delicate cellular redox systems that differ in the subcellular compartments with regard to their concentrations and depending on the physiological or pathological status of cells and organelles (i.e., circadian rhythm, cell cycle, metabolic need, disease stadium). As reactive species are used as signaling molecules, non-targeted broad-spectrum antioxidants in many cases will fail their therapeutic aim. Precision medicine is called to remedy the situation.
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9
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Causer AJ, Khalaf M, Klein Rot E, Brand K, Smith J, Bailey SJ, Cummings MH, Shepherd AI, Saynor ZL, Shute JK. CFTR limits F-actin formation and promotes morphological alignment with flow in human lung microvascular endothelial cells. Physiol Rep 2021; 9:e15128. [PMID: 34851051 PMCID: PMC8634629 DOI: 10.14814/phy2.15128] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2021] [Revised: 11/05/2021] [Accepted: 11/05/2021] [Indexed: 12/15/2022] Open
Abstract
Micro- and macrovascular endothelial dysfunction in response to shear stress has been observed in cystic fibrosis (CF), and has been associated with inflammation and oxidative stress. We tested the hypothesis that the cystic fibrosis transmembrane conductance regulator (CFTR) regulates endothelial actin cytoskeleton dynamics and cellular alignment in response to flow. Human lung microvascular endothelial cells (HLMVEC) were cultured with either the CFTR inhibitor GlyH-101 (20 µM) or CFTRinh-172 (20 µM), tumor necrosis factor (TNF)-α (10 ng/ml) or a vehicle control (0.1% dimethyl sulfoxide) during 24 and 48 h of exposure to shear stress (11.1 dynes/cm2 ) or under static control conditions. Cellular morphology and filamentous actin (F-actin) were assessed using immunocytochemistry. [Nitrite] and endothelin-1 ([ET-1]) were determined in cell culture supernatant by ozone-based chemiluminescence and ELISA, respectively. Treatment of HLMVECs with both CFTR inhibitors prevented alignment of HLMVEC in the direction of flow after 24 and 48 h of shear stress, compared to vehicle control (both p < 0.05). Treatment with TNF-α significantly increased total F-actin after 24 h versus control (p < 0.05), an effect that was independent of shear stress. GlyH-101 significantly increased F-actin after 24 h of shear stress versus control (p < 0.05), with a significant (p < 0.05) reduction in cortical F-actin under both static and flow conditions. Shear stress decreased [ET-1] after 24 h (p < 0.05) and increased [nitrite] after 48 h (p < 0.05), but neither [nitrite] nor [ET-1] was affected by GlyH-101 (p > 0.05). CFTR appears to limit cytosolic actin polymerization, while maintaining a cortical rim actin distribution that is important for maintaining barrier integrity and promoting alignment with flow, without effects on endothelial nitrite or ET-1 production.
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Affiliation(s)
- Adam J. Causer
- Department for HealthUniversity of BathBathUK
- School of Pharmacy and Biomedical SciencesUniversity of PortsmouthPortsmouthUK
- School of Sport, Health and Exercise ScienceUniversity of PortsmouthPortsmouthUK
| | - Maha Khalaf
- School of Pharmacy and Biomedical SciencesUniversity of PortsmouthPortsmouthUK
| | - Emily Klein Rot
- School of Pharmacy and Biomedical SciencesUniversity of PortsmouthPortsmouthUK
- School of Life Science, Engineering & DesignSaxion UniversityEnschedeThe Netherlands
| | - Kimberly Brand
- School of Pharmacy and Biomedical SciencesUniversity of PortsmouthPortsmouthUK
- School of Life Science, Engineering & DesignSaxion UniversityEnschedeThe Netherlands
| | - James Smith
- School of Pharmacy and Biomedical SciencesUniversity of PortsmouthPortsmouthUK
| | - Stephen J. Bailey
- School of Sport, Exercise and Health SciencesLoughborough UniversityLoughboroughUK
| | - Michael H. Cummings
- Department of Diabetes and EndocrinologyQueen Alexandra HospitalPortsmouthUK
| | - Anthony I. Shepherd
- School of Sport, Health and Exercise ScienceUniversity of PortsmouthPortsmouthUK
| | - Zoe L. Saynor
- School of Sport, Health and Exercise ScienceUniversity of PortsmouthPortsmouthUK
| | - Janis K. Shute
- School of Pharmacy and Biomedical SciencesUniversity of PortsmouthPortsmouthUK
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10
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BACH1, the master regulator of oxidative stress, has a dual effect on CFTR expression. Biochem J 2021; 478:3741-3756. [PMID: 34605540 PMCID: PMC8589331 DOI: 10.1042/bcj20210252] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2021] [Revised: 09/30/2021] [Accepted: 10/01/2021] [Indexed: 02/07/2023]
Abstract
The cystic fibrosis transmembrane conductance regulator (CFTR) gene lies within a topologically associated domain (TAD) in which multiple cis-regulatory elements (CREs) and transcription factors (TFs) regulate its cell-specific expression. The CREs are recruited to the gene promoter by a looping mechanism that depends upon both architectural proteins and specific TFs. An siRNA screen to identify TFs coordinating CFTR expression in airway epithelial cells suggested an activating role for BTB domain and CNC homolog 1 (BACH1). BACH1 is a ubiquitous master regulator of the cellular response to oxidative stress. Here, we show that BACH1 may have a dual effect on CFTR expression by direct occupancy of CREs at physiological oxygen (∼8%), while indirectly modulating expression under conditions of oxidative stress. Hence BACH1, can activate or repress the same gene, to fine tune expression in response to environmental cues such as cell stress. Furthermore, our 4C-seq data suggest that BACH1 can also directly regulate CFTR gene expression by modulating locus architecture through occupancy at known enhancers and structural elements, and depletion of BACH1 alters the higher order chromatin structure.
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11
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Declercq M, de Zeeuw P, Conchinha NV, Geldhof V, Ramalho AS, García-Caballero M, Brepoels K, Ensinck M, Carlon MS, Bird MJ, Vinckier S, Proesmans M, Vermeulen F, Dupont L, Ghesquière B, Dewerchin M, Carmeliet P, Cassiman D, Treps L, Eelen G, Witters P. Transcriptomic analysis of CFTR-impaired endothelial cells reveals a pro-inflammatory phenotype. Eur Respir J 2021; 57:13993003.00261-2020. [PMID: 33184117 DOI: 10.1183/13993003.00261-2020] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2020] [Accepted: 10/04/2020] [Indexed: 12/15/2022]
Abstract
Cystic fibrosis (CF) is a life-threatening disorder characterised by decreased pulmonary mucociliary and pathogen clearance, and an exaggerated inflammatory response leading to progressive lung damage. CF is caused by bi-allelic pathogenic variants of the cystic fibrosis transmembrane conductance regulator (CFTR) gene, which encodes a chloride channel. CFTR is expressed in endothelial cells (ECs) and EC dysfunction has been reported in CF patients, but a role for this ion channel in ECs regarding CF disease progression is poorly described.We used an unbiased RNA sequencing approach in complementary models of CFTR silencing and blockade (by the CFTR inhibitor CFTRinh-172) in human ECs to characterise the changes upon CFTR impairment. Key findings were further validated in vitro and in vivo in CFTR-knockout mice and ex vivo in CF patient-derived ECs.Both models of CFTR impairment revealed that EC proliferation, migration and autophagy were downregulated. Remarkably though, defective CFTR function led to EC activation and a persisting pro-inflammatory state of the endothelium with increased leukocyte adhesion. Further validation in CFTR-knockout mice revealed enhanced leukocyte extravasation in lung and liver parenchyma associated with increased levels of EC activation markers. In addition, CF patient-derived ECs displayed increased EC activation markers and leukocyte adhesion, which was partially rescued by the CFTR modulators VX-770 and VX-809.Our integrated analysis thus suggests that ECs are no innocent bystanders in CF pathology, but rather may contribute to the exaggerated inflammatory phenotype, raising the question of whether normalisation of vascular inflammation might be a novel therapeutic strategy to ameliorate the disease severity of CF.
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Affiliation(s)
- Mathias Declercq
- Dept of Development and Regeneration, CF Centre, Woman and Child, KU Leuven, Leuven, Belgium.,Laboratory of Angiogenesis and Vascular Metabolism, Centre for Cancer Biology, VIB, Leuven, Belgium.,Laboratory of Angiogenesis and Vascular Metabolism, Dept of Oncology and Leuven Cancer Institute (LKI), KU Leuven, Leuven, Belgium
| | - Pauline de Zeeuw
- Laboratory of Angiogenesis and Vascular Metabolism, Centre for Cancer Biology, VIB, Leuven, Belgium.,Laboratory of Angiogenesis and Vascular Metabolism, Dept of Oncology and Leuven Cancer Institute (LKI), KU Leuven, Leuven, Belgium
| | - Nadine V Conchinha
- Laboratory of Angiogenesis and Vascular Metabolism, Centre for Cancer Biology, VIB, Leuven, Belgium.,Laboratory of Angiogenesis and Vascular Metabolism, Dept of Oncology and Leuven Cancer Institute (LKI), KU Leuven, Leuven, Belgium
| | - Vincent Geldhof
- Laboratory of Angiogenesis and Vascular Metabolism, Centre for Cancer Biology, VIB, Leuven, Belgium.,Laboratory of Angiogenesis and Vascular Metabolism, Dept of Oncology and Leuven Cancer Institute (LKI), KU Leuven, Leuven, Belgium
| | - Anabela S Ramalho
- Stem Cell and Developmental Biology, CF Centre, Woman and Child, KU Leuven, Leuven, Belgium
| | - Melissa García-Caballero
- Laboratory of Angiogenesis and Vascular Metabolism, Centre for Cancer Biology, VIB, Leuven, Belgium.,Laboratory of Angiogenesis and Vascular Metabolism, Dept of Oncology and Leuven Cancer Institute (LKI), KU Leuven, Leuven, Belgium
| | - Katleen Brepoels
- Laboratory of Angiogenesis and Vascular Metabolism, Centre for Cancer Biology, VIB, Leuven, Belgium.,Laboratory of Angiogenesis and Vascular Metabolism, Dept of Oncology and Leuven Cancer Institute (LKI), KU Leuven, Leuven, Belgium
| | - Marjolein Ensinck
- Laboratory for Molecular Virology and Drug Discovery, Dept of Pharmaceutical and Pharmacological Sciences, KU Leuven, Leuven, Belgium
| | - Marianne S Carlon
- Laboratory for Molecular Virology and Drug Discovery, Dept of Pharmaceutical and Pharmacological Sciences, KU Leuven, Leuven, Belgium
| | - Matthew J Bird
- Laboratory of Hepatology, Dept of Chronic Diseases, Metabolism and Ageing, KU Leuven, Leuven, Belgium.,Metabolomics Expertise Centre, Centre for Cancer Biology, VIB, Leuven, Belgium
| | - Stefan Vinckier
- Laboratory of Angiogenesis and Vascular Metabolism, Centre for Cancer Biology, VIB, Leuven, Belgium.,Laboratory of Angiogenesis and Vascular Metabolism, Dept of Oncology and Leuven Cancer Institute (LKI), KU Leuven, Leuven, Belgium
| | | | - François Vermeulen
- Dept of Respiratory Diseases, University Hospitals Leuven, Leuven, Belgium
| | - Lieven Dupont
- Dept of Pneumology, University Hospitals Leuven, Leuven, Belgium
| | - Bart Ghesquière
- Metabolomics Expertise Centre, Centre for Cancer Biology, VIB, Leuven, Belgium.,Metabolomics Expertise Centre, Dept of Oncology, KU Leuven, Leuven, Belgium
| | - Mieke Dewerchin
- Laboratory of Angiogenesis and Vascular Metabolism, Centre for Cancer Biology, VIB, Leuven, Belgium.,Laboratory of Angiogenesis and Vascular Metabolism, Dept of Oncology and Leuven Cancer Institute (LKI), KU Leuven, Leuven, Belgium
| | - Peter Carmeliet
- Laboratory of Angiogenesis and Vascular Metabolism, Centre for Cancer Biology, VIB, Leuven, Belgium.,Laboratory of Angiogenesis and Vascular Metabolism, Dept of Oncology and Leuven Cancer Institute (LKI), KU Leuven, Leuven, Belgium
| | - David Cassiman
- Laboratory of Hepatology, Dept of Chronic Diseases, Metabolism and Ageing, KU Leuven, Leuven, Belgium.,Centre of Metabolic Diseases, University Hospitals Leuven, Leuven, Belgium
| | - Lucas Treps
- Laboratory of Angiogenesis and Vascular Metabolism, Centre for Cancer Biology, VIB, Leuven, Belgium.,Laboratory of Angiogenesis and Vascular Metabolism, Dept of Oncology and Leuven Cancer Institute (LKI), KU Leuven, Leuven, Belgium.,Equal co-authorship
| | - Guy Eelen
- Laboratory of Angiogenesis and Vascular Metabolism, Centre for Cancer Biology, VIB, Leuven, Belgium.,Laboratory of Angiogenesis and Vascular Metabolism, Dept of Oncology and Leuven Cancer Institute (LKI), KU Leuven, Leuven, Belgium.,Equal co-authorship
| | - Peter Witters
- Dept of Development and Regeneration, CF Centre, Woman and Child, KU Leuven, Leuven, Belgium.,Dept of Paediatrics, University Hospitals Leuven, Leuven, Belgium.,Centre of Metabolic Diseases, University Hospitals Leuven, Leuven, Belgium.,Equal co-authorship
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12
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Treps L, Declercq M, Bousfia S, Carmeliet P, Witters P. Comparative meta-analysis of cystic fibrosis cell models suggests partial endothelial-to-mesenchymal transition. J Cyst Fibros 2021; 20:876-880. [PMID: 33858770 DOI: 10.1016/j.jcf.2021.03.019] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2020] [Revised: 03/05/2021] [Accepted: 03/17/2021] [Indexed: 12/12/2022]
Abstract
The mesenchymal conversion of epithelial cells (EMT) has been suggested as a potential contributor in cystic fibrosis (CF) disease progression. Endothelial cells (EndCs), the cells lining blood vessels, express functional CFTR and CFTR impairment promotes endothelial activation and dysfunction. However, if the mesenchymal switch also exists in CF EndCs remains uncharacterized. To understand whether the endothelial-to-mesenchymal transition (EndMT) could occur in CF, we have conducted a transcriptomic meta-analysis of primary CFTR-impaired and patient-derived EndCs, and further compared our results to data from CF epithelial cells (EpCs) where EMT has been demonstrated. As compared to EpCs, we show that CFTR-impaired EndCs display a limited signature of EndMT, and that expression of the mesenchymal inducer Twist1 remained unchanged. Nonetheless, the use of CFTR modulators reduced the expression of mesenchymal markers from CF patient-derived EndCs, suggesting an additional therapeutic added-value next to the known effect on CFTR ion transport.
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Affiliation(s)
- Lucas Treps
- Laboratory of Angiogenesis and Vascular Metabolism, Centre for Cancer Biology, VIB, Leuven, Belgium; Laboratory of Angiogenesis and Vascular Metabolism, Department of Oncology and Leuven Cancer Institute (LKI), KU Leuven, Leuven, Belgium; Université de Nantes, CNRS, INSERM, CRCINA, F-44000 Nantes, France.
| | - Mathias Declercq
- Laboratory of Angiogenesis and Vascular Metabolism, Centre for Cancer Biology, VIB, Leuven, Belgium; Laboratory of Angiogenesis and Vascular Metabolism, Department of Oncology and Leuven Cancer Institute (LKI), KU Leuven, Leuven, Belgium; Department of Development and Regeneration, CF Centre, Woman and Child, KU Leuven, Leuven, Belgium
| | - Siham Bousfia
- Laboratory of Angiogenesis and Vascular Metabolism, Centre for Cancer Biology, VIB, Leuven, Belgium; Laboratory of Angiogenesis and Vascular Metabolism, Department of Oncology and Leuven Cancer Institute (LKI), KU Leuven, Leuven, Belgium; Department of Development and Regeneration, CF Centre, Woman and Child, KU Leuven, Leuven, Belgium
| | - Peter Carmeliet
- Laboratory of Angiogenesis and Vascular Metabolism, Centre for Cancer Biology, VIB, Leuven, Belgium; Laboratory of Angiogenesis and Vascular Metabolism, Department of Oncology and Leuven Cancer Institute (LKI), KU Leuven, Leuven, Belgium
| | - Peter Witters
- Department of Development and Regeneration, CF Centre, Woman and Child, KU Leuven, Leuven, Belgium; Department of Paediatrics, University Hospitals Leuven, Leuven, Belgium; Centre of Metabolic Diseases, University Hospitals Leuven, Leuven, Belgium
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13
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Oliveira TL, Melo IS, Cardoso-Sousa L, Santos IA, El Zoghbi MB, Shimoura CG, Georjutti RP, Castro OW, Goulart LR, Jardim ACG, Cunha TM, Sabino-Silva R. Pathophysiology of SARS-CoV-2 in Lung of Diabetic Patients. Front Physiol 2020; 11:587013. [PMID: 33362575 PMCID: PMC7758507 DOI: 10.3389/fphys.2020.587013] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2020] [Accepted: 10/27/2020] [Indexed: 12/11/2022] Open
Abstract
Novel coronavirus disease (COVID-19) is an infectious disease caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Its impact on patients with comorbidities is clearly related to fatality cases, and diabetes has been linked to one of the most important causes of severity and mortality in SARS-CoV-2 infected patients. Substantial research progress has been made on COVID-19 therapeutics; however, effective treatments remain unsatisfactory. This unmet clinical need is robustly associated with the complexity of pathophysiological mechanisms described for COVID-19. Several key lung pathophysiological mechanisms promoted by SARS-CoV-2 have driven the response in normoglycemic and hyperglycemic subjects. There is sufficient evidence that glucose metabolism pathways in the lung are closely tied to bacterial proliferation, inflammation, oxidative stress, and pro-thrombotic responses, which lead to severe clinical outcomes. It is also likely that SARS-CoV-2 proliferation is affected by glucose metabolism of type I and type II cells. This review summarizes the current understanding of pathophysiology of SARS-CoV-2 in the lung of diabetic patients and highlights the changes in clinical outcomes of COVID-19 in normoglycemic and hyperglycemic conditions.
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Affiliation(s)
- Tales Lyra Oliveira
- Heart Institute, Faculty of Medicine, University of São Paulo, São Paulo, Brazil.,Medical School, Municipal University of São Caetano do Sul, São Paulo, Brazil
| | - Igor Santana Melo
- Institute of Biological Sciences and Health, Federal University of Alagoas, Alagoas, Brazil
| | - Léia Cardoso-Sousa
- Department of Physiology, Institute of Biomedical Sciences, Federal University of Uberlândia, Uberlândia, Brazil
| | - Igor Andrade Santos
- Laboratory of Virology, Institute of Biomedical Sciences, Federal University of Uberlândia, Uberlândia, Brazil
| | | | - Caroline Gusson Shimoura
- Department of Physiology and Anatomy, University of North Texas Health Science Center, Fort Worth, TX, United States
| | - Renata Pereira Georjutti
- Department of Physiology and Anatomy, University of North Texas Health Science Center, Fort Worth, TX, United States
| | - Olagide Wagner Castro
- Institute of Biological Sciences and Health, Federal University of Alagoas, Alagoas, Brazil
| | - Luiz Ricardo Goulart
- Institute of Biotechnology, Federal University of Uberlândia, Uberlândia, Brazil.,Department of Medical Microbiology and Immunology, University of California, Davis, Davis, CA, United States
| | - Ana Carolina Gomes Jardim
- Laboratory of Virology, Institute of Biomedical Sciences, Federal University of Uberlândia, Uberlândia, Brazil
| | - Thúlio Marquez Cunha
- Department of Pulmonology, School of Medicine, Federal University of Uberlândia, Uberlândia, Brazil
| | - Robinson Sabino-Silva
- Department of Physiology, Institute of Biomedical Sciences, Federal University of Uberlândia, Uberlândia, Brazil
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14
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Saynor ZL, Gruet M, Rodriguez-Miguelez P, Harris RA. Oxygen transport and utilisation during exercise in cystic fibrosis: contributors to exercise intolerance. Exp Physiol 2020; 105:1979-1983. [PMID: 33119143 DOI: 10.1113/ep088106] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2020] [Accepted: 10/21/2020] [Indexed: 01/04/2023]
Abstract
NEW FINDINGS What is the topic of this review? This review highlights the central and peripheral mechanisms that alter oxygen transport and utilisation and thereby contribute to exercise limitation in people with cystic fibrosis, considering also viable therapeutic targets for intervention. What advances does it highlight? Although traditionally considered a respiratory condition, pathological intramuscular and cardiovascular changes in people with cystic fibrosis appear to be key determinants of exercise intolerance up until the later stages of respiratory disease. Even young, habitually active patients with normal lung function experience multisystemic abnormalities, which play a role in exercise intolerance. ABSTRACT Cystic fibrosis (CF) is a complex condition, commonly associated with exercise limitation. The mechanisms responsible for this in CF are of interest, given that lower aerobic fitness is associated with an increased risk of being hospitalised with pulmonary exacerbation, a poorer quality of life and a poorer prognosis. Pathophysiological changes in lung function are considered central to CF, and may contribute to exercise limitation. However, it is now clear that the pathogenesis of exercise limitation in this population is multifactorial, with alterations in cardiovascular, muscle and pulmonary function contributing. Whilst some of these changes are attributable to respiratory disease per se, the CF transmembrane conductance regulator protein is also found in skeletal muscle and the vascular endothelium and can directly alter central and localised oxygen delivery, as well as the ability to effectively extract and utilise oxygen at the myocyte level. Since intense exercise poses considerable challenges to arterial oxygen content and/or blood flow and its supply to the working skeletal muscle, evaluating the exercise physiology of people with CF has helped us understand the mechanisms underlying exercise intolerance. Through several investigations over recent years, we have collectively demonstrated that people with CF exhibit reduced skeletal muscle oxygen extraction and utilisation during exercise, with a lesser contribution from haemodynamic or chronotropic mechanisms. Taken together, our findings highlight the importance of targeting mechanisms of skeletal muscle oxygen utilisation in CF to improve exercise tolerance and we offer potential therapeutic interventional strategies.
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Affiliation(s)
- Zoe L Saynor
- School of Sport, Health and Exercise Science, Faculty of Science and Health, University of Portsmouth, Portsmouth, UK
| | - Mathieu Gruet
- Laboratory of the Impact of Physical Activity on Health (IAPS), Toulon University, Toulon, France
| | - Paula Rodriguez-Miguelez
- Department of Kinesiology and Health Sciences, College of Humanities and Sciences, Virginia Commonwealth University, Richmond, VA, USA
| | - Ryan A Harris
- Georgia Prevention Institute, Department of Medicine, Augusta University, Augusta, GA, USA
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