1
|
Goggins BJ, Minahan K, Sherwin S, Soh WS, Pryor J, Bruce J, Liu G, Mathe A, Knight D, Horvat JC, Walker MM, Keely S. Pharmacological HIF-1 stabilization promotes intestinal epithelial healing through regulation of α-integrin expression and function. Am J Physiol Gastrointest Liver Physiol 2021; 320:G420-G438. [PMID: 33470153 DOI: 10.1152/ajpgi.00192.2020] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/20/2020] [Revised: 12/08/2020] [Accepted: 12/14/2020] [Indexed: 01/31/2023]
Abstract
Intestinal epithelia are critical for maintaining gastrointestinal homeostasis. Epithelial barrier injury, causing inflammation and vascular damage, results in inflammatory hypoxia, and thus, healing occurs in an oxygen-restricted environment. The transcription factor hypoxia-inducible factor (HIF)-1 regulates genes important for cell survival and repair, including the cell adhesion protein β1-integrin. Integrins function as αβ-dimers, and α-integrin-matrix binding is critical for cell migration. We hypothesized that HIF-1 stabilization accelerates epithelial migration through integrin-dependent pathways. We aimed to examine functional and posttranslational activity of α-integrins during HIF-1-mediated intestinal epithelial healing. Wound healing was assessed in T84 monolayers over 24 h with/without prolyl-hydroxylase inhibitor (PHDi) (GB-004), which stabilizes HIF-1. Gene and protein expression were measured by RT-PCR and immunoblot, and α-integrin localization was assessed by immunofluorescence. α-integrin function was assessed by antibody-mediated blockade, and integrin α6 regulation was determined by HIF-1α chromatin immunoprecipitation. Models of mucosal wounding and 2,4,6-trinitrobenzenesulfonic acid (TNBS)-induced colitis were used to examine integrin expression and localization in vivo. PHDi treatment accelerated wound closure and migration within 12 h, associated with increased integrin α2 and α6 protein, but not α3. Functional blockade of integrins α2 and α6 inhibited PHDi-mediated accelerated wound closure. HIF-1 bound directly to the integrin α6 promoter. PHDi treatment accelerated mucosal healing, which was associated with increased α6 immunohistochemical staining in wound-associated epithelium and wound-adjacent tissue. PHDi treatment increased α6 protein levels in colonocytes of TNBS mice and induced α6 staining in regenerating crypts and reepithelialized inflammatory lesions. Together, these data demonstrate a role for HIF-1 in regulating both integrin α2 and α6 responses during intestinal epithelial healing.NEW & NOTEWORTHY HIF-1 plays an important role in epithelial restitution, selectively inducing integrins α6 and α2 to promote migration and proliferation, respectively. HIF-stabilizing prolyl-hydroxylase inhibitors accelerate intestinal mucosal healing by inducing epithelial integrin expression.
Collapse
Affiliation(s)
- Bridie J Goggins
- School of Biomedical Sciences and Pharmacy, University of Newcastle, Callaghan, New South Wales, Australia
- Hunter Medical Research Institute, New Lambton Heights, New South Wales, Australia
- Gastrointestinal Research Group, University of Newcastle, New South Wales, Australia
- Priority Research Centre for Digestive Health and Neurogastroenterology, Hunter Medical Research Institute and University of Newcastle, Newcastle, New South Wales, Australia
| | - Kyra Minahan
- School of Biomedical Sciences and Pharmacy, University of Newcastle, Callaghan, New South Wales, Australia
- Hunter Medical Research Institute, New Lambton Heights, New South Wales, Australia
- Gastrointestinal Research Group, University of Newcastle, New South Wales, Australia
- Priority Research Centre for Digestive Health and Neurogastroenterology, Hunter Medical Research Institute and University of Newcastle, Newcastle, New South Wales, Australia
| | - Simonne Sherwin
- School of Biomedical Sciences and Pharmacy, University of Newcastle, Callaghan, New South Wales, Australia
- Hunter Medical Research Institute, New Lambton Heights, New South Wales, Australia
- Gastrointestinal Research Group, University of Newcastle, New South Wales, Australia
- Priority Research Centre for Digestive Health and Neurogastroenterology, Hunter Medical Research Institute and University of Newcastle, Newcastle, New South Wales, Australia
| | - Wai S Soh
- School of Biomedical Sciences and Pharmacy, University of Newcastle, Callaghan, New South Wales, Australia
- Hunter Medical Research Institute, New Lambton Heights, New South Wales, Australia
- Gastrointestinal Research Group, University of Newcastle, New South Wales, Australia
- Priority Research Centre for Digestive Health and Neurogastroenterology, Hunter Medical Research Institute and University of Newcastle, Newcastle, New South Wales, Australia
| | - Jennifer Pryor
- School of Biomedical Sciences and Pharmacy, University of Newcastle, Callaghan, New South Wales, Australia
- Hunter Medical Research Institute, New Lambton Heights, New South Wales, Australia
- Gastrointestinal Research Group, University of Newcastle, New South Wales, Australia
- Priority Research Centre for Digestive Health and Neurogastroenterology, Hunter Medical Research Institute and University of Newcastle, Newcastle, New South Wales, Australia
| | - Jessica Bruce
- School of Biomedical Sciences and Pharmacy, University of Newcastle, Callaghan, New South Wales, Australia
- Hunter Medical Research Institute, New Lambton Heights, New South Wales, Australia
- Gastrointestinal Research Group, University of Newcastle, New South Wales, Australia
- Priority Research Centre for Digestive Health and Neurogastroenterology, Hunter Medical Research Institute and University of Newcastle, Newcastle, New South Wales, Australia
| | - Gang Liu
- School of Biomedical Sciences and Pharmacy, University of Newcastle, Callaghan, New South Wales, Australia
- Hunter Medical Research Institute, New Lambton Heights, New South Wales, Australia
- Gastrointestinal Research Group, University of Newcastle, New South Wales, Australia
- Priority Research Centre for Digestive Health and Neurogastroenterology, Hunter Medical Research Institute and University of Newcastle, Newcastle, New South Wales, Australia
| | - Andrea Mathe
- School of Biomedical Sciences and Pharmacy, University of Newcastle, Callaghan, New South Wales, Australia
- Hunter Medical Research Institute, New Lambton Heights, New South Wales, Australia
- Gastrointestinal Research Group, University of Newcastle, New South Wales, Australia
- Priority Research Centre for Digestive Health and Neurogastroenterology, Hunter Medical Research Institute and University of Newcastle, Newcastle, New South Wales, Australia
| | - Darryl Knight
- School of Biomedical Sciences and Pharmacy, University of Newcastle, Callaghan, New South Wales, Australia
- Hunter Medical Research Institute, New Lambton Heights, New South Wales, Australia
| | - Jay C Horvat
- School of Biomedical Sciences and Pharmacy, University of Newcastle, Callaghan, New South Wales, Australia
- Hunter Medical Research Institute, New Lambton Heights, New South Wales, Australia
| | - Marjorie M Walker
- Hunter Medical Research Institute, New Lambton Heights, New South Wales, Australia
- Priority Research Centre for Digestive Health and Neurogastroenterology, Hunter Medical Research Institute and University of Newcastle, Newcastle, New South Wales, Australia
| | - Simon Keely
- School of Biomedical Sciences and Pharmacy, University of Newcastle, Callaghan, New South Wales, Australia
- Hunter Medical Research Institute, New Lambton Heights, New South Wales, Australia
- Gastrointestinal Research Group, University of Newcastle, New South Wales, Australia
- Priority Research Centre for Digestive Health and Neurogastroenterology, Hunter Medical Research Institute and University of Newcastle, Newcastle, New South Wales, Australia
| |
Collapse
|
2
|
Page LK, Staples KJ, Spalluto CM, Watson A, Wilkinson TMA. Influence of Hypoxia on the Epithelial-Pathogen Interactions in the Lung: Implications for Respiratory Disease. Front Immunol 2021; 12:653969. [PMID: 33868294 PMCID: PMC8044850 DOI: 10.3389/fimmu.2021.653969] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2021] [Accepted: 03/09/2021] [Indexed: 12/11/2022] Open
Abstract
Under normal physiological conditions, the lung remains an oxygen rich environment. However, prominent regions of hypoxia are a common feature of infected and inflamed tissues and many chronic inflammatory respiratory diseases are associated with mucosal and systemic hypoxia. The airway epithelium represents a key interface with the external environment and is the first line of defense against potentially harmful agents including respiratory pathogens. The protective arsenal of the airway epithelium is provided in the form of physical barriers, and the production of an array of antimicrobial host defense molecules, proinflammatory cytokines and chemokines, in response to activation by receptors. Dysregulation of the airway epithelial innate immune response is associated with a compromised immunity and chronic inflammation of the lung. An increasing body of evidence indicates a distinct role for hypoxia in the dysfunction of the airway epithelium and in the responses of both innate immunity and of respiratory pathogens. Here we review the current evidence around the role of tissue hypoxia in modulating the host-pathogen interaction at the airway epithelium. Furthermore, we highlight the work needed to delineate the role of tissue hypoxia in the pathophysiology of chronic inflammatory lung diseases such as asthma, cystic fibrosis, and chronic obstructive pulmonary disease in addition to novel respiratory diseases such as COVID-19. Elucidating the molecular mechanisms underlying the epithelial-pathogen interactions in the setting of hypoxia will enable better understanding of persistent infections and complex disease processes in chronic inflammatory lung diseases and may aid the identification of novel therapeutic targets and strategies.
Collapse
Affiliation(s)
- Lee K Page
- Clinical and Experimental Sciences, University of Southampton Faculty of Medicine, Southampton, United Kingdom
| | - Karl J Staples
- Clinical and Experimental Sciences, University of Southampton Faculty of Medicine, Southampton, United Kingdom.,NIHR Southampton Biomedical Research Centre, Southampton Centre for Biomedical Research, Southampton General Hospital, Southampton, United Kingdom
| | - C Mirella Spalluto
- Clinical and Experimental Sciences, University of Southampton Faculty of Medicine, Southampton, United Kingdom.,NIHR Southampton Biomedical Research Centre, Southampton Centre for Biomedical Research, Southampton General Hospital, Southampton, United Kingdom
| | - Alastair Watson
- Clinical and Experimental Sciences, University of Southampton Faculty of Medicine, Southampton, United Kingdom.,NIHR Southampton Biomedical Research Centre, Southampton Centre for Biomedical Research, Southampton General Hospital, Southampton, United Kingdom.,Birmingham Medical School, University of Birmingham, Birmingham, United Kingdom
| | - Tom M A Wilkinson
- Clinical and Experimental Sciences, University of Southampton Faculty of Medicine, Southampton, United Kingdom.,NIHR Southampton Biomedical Research Centre, Southampton Centre for Biomedical Research, Southampton General Hospital, Southampton, United Kingdom
| |
Collapse
|