1
|
Chen R, Wang Y, Zhang Z, Wang X, Li Y, Wang M, Wang H, Dong M, Zhou Q, Yang L. The Role of SLIT3-ROBO4 Signaling in Endoplasmic Reticulum Stress-Induced Delayed Corneal Epithelial and Nerve Regeneration. Invest Ophthalmol Vis Sci 2024; 65:8. [PMID: 38700874 PMCID: PMC11077912 DOI: 10.1167/iovs.65.5.8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2023] [Accepted: 03/23/2024] [Indexed: 05/08/2024] Open
Abstract
Purpose In the present study, we aim to elucidate the underlying molecular mechanism of endoplasmic reticulum (ER) stress induced delayed corneal epithelial wound healing and nerve regeneration. Methods Human limbal epithelial cells (HLECs) were treated with thapsigargin to induce excessive ER stress and then RNA sequencing was performed. Immunofluorescence, qPCR, Western blot, and ELISA were used to detect the expression changes of SLIT3 and its receptors ROBO1-4. The role of recombinant SLIT3 protein in corneal epithelial proliferation and migration were assessed by CCK8 and cell scratch assay, respectively. Thapsigargin, exogenous SLIT3 protein, SLIT3-specific siRNA, and ROBO4-specific siRNA was injected subconjunctivally to evaluate the effects of different intervention on corneal epithelial and nerve regeneration. In addition, Ki67 staining was performed to evaluate the proliferation ability of epithelial cells. Results Thapsigargin suppressed normal corneal epithelial and nerve regeneration significantly. RNA sequencing genes related to development and regeneration revealed that thapsigargin induced ER stress significantly upregulated the expression of SLIT3 and ROBO4 in corneal epithelial cells. Exogenous SLIT3 inhibited normal corneal epithelial injury repair and nerve regeneration, and significantly suppressed the proliferation and migration ability of cultured mouse corneal epithelial cells. SLIT3 siRNA inhibited ROBO4 expression and promoted epithelial wound healing under thapsigargin treatment. ROBO4 siRNA significantly attenuated the delayed corneal epithelial injury repair and nerve regeneration induced by SLIT3 treatment or thapsigargin treatment. Conclusions ER stress inhibits corneal epithelial injury repair and nerve regeneration may be related with the upregulation of SLIT3-ROBO4 pathway.
Collapse
Affiliation(s)
- Rong Chen
- State Key Laboratory Cultivation Base, Shandong Provincial Key Laboratory of Ophthalmology, Shandong Eye Institute, Shandong First Medical University & Shandong Academy of Medical Sciences, Qingdao, China
| | - Yao Wang
- State Key Laboratory Cultivation Base, Shandong Provincial Key Laboratory of Ophthalmology, Shandong Eye Institute, Shandong First Medical University & Shandong Academy of Medical Sciences, Qingdao, China
| | - Zhenzhen Zhang
- State Key Laboratory Cultivation Base, Shandong Provincial Key Laboratory of Ophthalmology, Shandong Eye Institute, Shandong First Medical University & Shandong Academy of Medical Sciences, Qingdao, China
| | - Xiaolei Wang
- State Key Laboratory Cultivation Base, Shandong Provincial Key Laboratory of Ophthalmology, Shandong Eye Institute, Shandong First Medical University & Shandong Academy of Medical Sciences, Qingdao, China
| | - Ya Li
- State Key Laboratory Cultivation Base, Shandong Provincial Key Laboratory of Ophthalmology, Shandong Eye Institute, Shandong First Medical University & Shandong Academy of Medical Sciences, Qingdao, China
| | - Min Wang
- State Key Laboratory Cultivation Base, Shandong Provincial Key Laboratory of Ophthalmology, Shandong Eye Institute, Shandong First Medical University & Shandong Academy of Medical Sciences, Qingdao, China
| | - Huifeng Wang
- State Key Laboratory Cultivation Base, Shandong Provincial Key Laboratory of Ophthalmology, Shandong Eye Institute, Shandong First Medical University & Shandong Academy of Medical Sciences, Qingdao, China
| | - Muchen Dong
- Eye Institute of Shandong First Medical University, Eye Hospital of Shandong First Medical University (Shandong Eye Hospital), Jinan, China
| | - Qingjun Zhou
- State Key Laboratory Cultivation Base, Shandong Provincial Key Laboratory of Ophthalmology, Shandong Eye Institute, Shandong First Medical University & Shandong Academy of Medical Sciences, Qingdao, China
| | - Lingling Yang
- State Key Laboratory Cultivation Base, Shandong Provincial Key Laboratory of Ophthalmology, Shandong Eye Institute, Shandong First Medical University & Shandong Academy of Medical Sciences, Qingdao, China
| |
Collapse
|
2
|
Wu J, Huang Y, Yu H, Li K, Zhang S, Qiao G, Liu X, Duan H, Huang Y, So KF, Yang Z, Li X, Wang L. Chitosan-based thermosensitive hydrogel with long-term release of murine nerve growth factor for neurotrophic keratopathy. Neural Regen Res 2024; 19:680-686. [PMID: 37721301 PMCID: PMC10581555 DOI: 10.4103/1673-5374.380908] [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: 01/28/2023] [Revised: 05/15/2023] [Accepted: 06/16/2023] [Indexed: 09/19/2023] Open
Abstract
Neurotrophic keratopathy is a persistent defect of the corneal epithelium, with or without stromal ulceration, due to corneal nerve deficiency caused by a variety of etiologies. The treatment options for neurotrophic keratopathy are limited. In this study, an ophthalmic solution was constructed from a chitosan-based thermosensitive hydrogel with long-term release of murine nerve growth factor (CTH-mNGF). Its effectiveness was evaluated in corneal denervation (CD) mice and patients with neurotrophic keratopathy. In the preclinical setting, CTH-mNGF was assessed in a murine corneal denervation model. CTH-mNGF was transparent, thermosensitive, and ensured sustained release of mNGF for over 20 hours on the ocular surface, maintaining the local mNGF concentration around 1300 pg/mL in vivo. Corneal denervation mice treated with CTH-mNGF for 10 days showed a significant increase in corneal nerve area and total corneal nerve length compared with non-treated and CTH treated mice. A subsequent clinical trial of CTH-mNGF was conducted in patients with stage 2 or 3 neurotrophic keratopathy. Patients received topical CTH-mNGF twice daily for 8 weeks. Fluorescein sodium images, Schirmer's test, intraocular pressure, Cochet-Bonnet corneal perception test, and best corrected visual acuity were evaluated. In total, six patients (total of seven eyes) diagnosed with neurotrophic keratopathy were enrolled. After 8 weeks of CTH-mNGF treatment, all participants showed a decreased area of corneal epithelial defect, as stained by fluorescence. Overall, six out of seven eyes had fluorescence staining scores < 5. Moreover, best corrected visual acuity, intraocular pressure, Schirmer's test and Cochet-Bonnet corneal perception test results showed no significant improvement. An increase in corneal nerve density was observed by in vivo confocal microscopy after 8 weeks of CTH-mNGF treatment in three out of seven eyes. This study demonstrates that CTH-mNGF is transparent, thermosensitive, and has sustained-release properties. Its effectiveness in healing corneal epithelial defects in all eyes with neurotrophic keratopathy suggests CTH-mNGF has promising application prospects in the treatment of neurotrophic keratopathy, being convenient and cost effective.
Collapse
Affiliation(s)
- Jie Wu
- Department of Ophthalmology, the Third Medical Center, Chinese PLA General Hospital, Beijing, China
- The PLA Medical College, Department of Nephrology, Chinese PLA Institute of Nephrology, State Key Laboratory of Kidney Diseases, National Clinical Research Center for Kidney Diseases, Beijing, China
- Department of Ophthalmology, Hainan Hospital of Chinese PLA General Hospital, Sanya, Hainan Province, China
| | - Yulei Huang
- Medical School of Chinese PLA, Beijing, China
| | - Hanrui Yu
- Medical School of Chinese PLA, Beijing, China
| | - Kaixiu Li
- Medical School of Chinese PLA, Beijing, China
| | | | | | - Xiao Liu
- Department of Neurobiology, School of Basic Medical Sciences, Capital Medical University, Beijing, China
| | - Hongmei Duan
- Department of Neurobiology, School of Basic Medical Sciences, Capital Medical University, Beijing, China
| | - Yifei Huang
- Department of Ophthalmology, the Third Medical Center, Chinese PLA General Hospital, Beijing, China
| | - Kwok-Fai So
- Guangdong-Hongkong-Macau Institute of CNS Regeneration, Ministry of Education CNS Regeneration Collaborative Joint Laboratory, Jinan University, Guangzhou, Guangdong Province, China
- Bioland Laboratory (Guangzhou Regenerative Medicine and Health Guangdong Laboratory), Guangzhou, Guangdong Province, China
- Department of Ophthalmology and State Key Laboratory of Brain and Cognitive Sciences, The University of Hong Kong, Hong Kong Special Administrative Region, China
- Center for Brain Science and Brain-Inspired Intelligence, Guangdong-Hong Kong-Macao Greater Bay Area, Guangzhou, Guangdong Province, China
- Co-innovation Center of Neuroregeneration, Nantong University, Nantong, Jiangsu Province, China
| | - Zhaoyang Yang
- Department of Neurobiology, School of Basic Medical Sciences, Capital Medical University, Beijing, China
| | - Xiaoguang Li
- Department of Neurobiology, School of Basic Medical Sciences, Capital Medical University, Beijing, China
- School of Engineering Medicine, Beijing Key Laboratory for Biomaterials and Neural Regeneration, Beihang University, Beijing, China
- Beijing International Cooperation Bases for Science and Technology on Biomaterials and Neural Regeneration, Beijing Advanced Innovation Center for Big Data-Based Precision Medicine, Beihang University, Beijing, China
| | - Liqiang Wang
- Department of Ophthalmology, the Third Medical Center, Chinese PLA General Hospital, Beijing, China
- The PLA Medical College, Department of Nephrology, Chinese PLA Institute of Nephrology, State Key Laboratory of Kidney Diseases, National Clinical Research Center for Kidney Diseases, Beijing, China
| |
Collapse
|
3
|
van Setten GB. Ocular Surface Allostasis-When Homeostasis Is Lost: Challenging Coping Potential, Stress Tolerance, and Resilience. Biomolecules 2023; 13:1246. [PMID: 37627311 PMCID: PMC10452761 DOI: 10.3390/biom13081246] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2023] [Revised: 07/20/2023] [Accepted: 07/27/2023] [Indexed: 08/27/2023] Open
Abstract
The loss of ocular surface (OS) homeostasis characterizes the onset of dry eye disease. Resilience defines the ability to withstand this threat, reflecting the ability of the ocular surface to cope with and bounce back after challenging events. The coping capacity of the OS defines the ability to successfully manage cellular stress. Cellular stress, which is central to the outcome of the pathophysiology of dry eye disease, is characterized by intensity, continuity, and receptivity, which lead to the loss of homeostasis, resulting in a phase of autocatalytic dysregulation, an event that is not well-defined. To better define this event, here, we present a model providing a potential approach when homeostasis is challenged and the coping capacities have reached their limits, resulting in the stage of heterostasis, in which the dysregulated cellular stress mechanisms take over, leading to dry eye disease. The main feature of the proposed model is the concept that, prior to the initiation of the events leading to cellular stress, there is a period of intense activation of all available coping mechanisms preventing the imminent dysregulation of ocular surface homeostasis. When the remaining coping mechanisms and resilience potential have been maximally exploited and have, finally, been exceeded, there will be a transition to manifest disease with all the well-known signs and symptoms, with a shift to allostasis, reflecting the establishment of another state of balance. The intention of this review was to show that it is possibly the phase of heterostasis preceding the establishment of allostasis that offers a better chance for therapeutic intervention and optimized recovery. Once allostasis has been established, as a new steady-state of balance at a higher level of constant cell stress and inflammation, treatment may be far more difficult, and the potential for reversal is drastically decreased. Homeostasis, once lost, can possibly not be fully recovered. The processes established during heterostasis and allostasis require different approaches and treatments for their control, indicating that the current treatment options for homeostasis need to be adapted to a more-demanding situation. The loss of homeostasis necessarily implies the establishment of a new balance; here, we refer to such a state as allostasis.
Collapse
Affiliation(s)
- Gysbert-Botho van Setten
- St. Eriks Eye Hospital, 171 04 Solna, Sweden;
- Lab of DOHF and Wound Healing, Division of Eye and Vision, Department of Clinical Neuroscience, Karolinska Institutet, Eugeniavägen 12/Level 6, 171 04 Solna, Sweden
| |
Collapse
|
4
|
Sumioka T, Matsumoto KI, Reinach PS, Saika S. Tenascins and osteopontin in biological response in cornea. Ocul Surf 2023; 29:131-149. [PMID: 37209968 DOI: 10.1016/j.jtos.2023.05.005] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2023] [Revised: 05/01/2023] [Accepted: 05/16/2023] [Indexed: 05/22/2023]
Abstract
The structural composition, integrity and regular curvature of the cornea contribute to the maintenance of its transparency and vision. Disruption of its integrity caused by injury results in scarring, inflammation and neovascularization followed by losses in transparency. These sight compromising effects is caused by dysfunctional corneal resident cell responses induced by the wound healing process. Upregulation of growth factors/cytokines and neuropeptides affect development of aberrant behavior. These factors trigger keratocytes to first transform into activated fibroblasts and then to myofibroblasts. Myofibroblasts express extracellular matrix components for tissue repair and contract the tissue to facilitate wound closure. Proper remodeling following primary repair is critical for restoration of transparency and visual function. Extracellular matrix components contributing to the healing process are divided into two groups; a group of classical tissue structural components and matrix macromolecules that modulate cell behaviors/activities besides being integrated into the matrix structure. The latter components are designated as matricellular proteins. Their functionality is elicited through mechanisms which modulate the scaffold integrity, cell behaviors, activation/inactivation of either growth factors or cytoplasmic signaling regulation. We discuss here the functional roles of matricellular proteins in mediating injury-induced corneal tissue repair. The roles are described of major matricellular proteins, which include tenascin C, tenascin X and osteopontin. Focus is directed towards dealing with their roles in modulating individual activities of wound healing-related growth factors, e. g., transforming growth factor β (TGF β). Modulation of matricellular protein functions could encompass a potential novel strategy to improve the outcome of injury-induced corneal wound healing.
Collapse
Affiliation(s)
- Takayoshi Sumioka
- Department of Ophthalmology, Wakayama Medical University School of Medicine, 811-1 Kimiidera, 641-0012, Japan.
| | - Ken-Ichi Matsumoto
- Department of Biosignaling and Radioisotope Experiment, Interdisciplinary Center for Science Research, Head Office for Research and Academic Information, Shimane University, 89-1 Enya-cho, Izumo, 693-8501, Japan
| | - Peter Sol Reinach
- Department of Biological. Sciences SUNY Optometry, New York, NY, 10036, USA
| | - Shizuya Saika
- Department of Ophthalmology, Wakayama Medical University School of Medicine, 811-1 Kimiidera, 641-0012, Japan
| |
Collapse
|
5
|
MAPK Pathways in Ocular Pathophysiology: Potential Therapeutic Drugs and Challenges. Cells 2023; 12:cells12040617. [PMID: 36831285 PMCID: PMC9954064 DOI: 10.3390/cells12040617] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2023] [Revised: 02/05/2023] [Accepted: 02/07/2023] [Indexed: 02/17/2023] Open
Abstract
Mitogen-activated protein kinase (MAPK) pathways represent ubiquitous cellular signal transduction pathways that regulate all aspects of life and are frequently altered in disease. Once activated through phosphorylation, these MAPKs in turn phosphorylate and activate transcription factors present either in the cytoplasm or in the nucleus, leading to the expression of target genes and, as a consequence, they elicit various biological responses. The aim of this work is to provide a comprehensive review focusing on the roles of MAPK signaling pathways in ocular pathophysiology and the potential to influence these for the treatment of eye diseases. We summarize the current knowledge of identified MAPK-targeting compounds in the context of ocular diseases such as macular degeneration, cataract, glaucoma and keratopathy, but also in rare ocular diseases where the cell differentiation, proliferation or migration are defective. Potential therapeutic interventions are also discussed. Additionally, we discuss challenges in overcoming the reported eye toxicity of some MAPK inhibitors.
Collapse
|
6
|
Djptpn11 is indispensable for planarian regeneration by affecting early wound response genes expression and the Wnt pathway. Biochimie 2022; 201:184-195. [PMID: 35868605 DOI: 10.1016/j.biochi.2022.07.007] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2022] [Revised: 07/14/2022] [Accepted: 07/15/2022] [Indexed: 12/22/2022]
Abstract
Planarian is an ideal model system of studying regeneration. Stem cell system and positional control genes (PCGs) are two important factors for perfect regeneration of planarians and they combine to promote their regeneration. Even so, how wounds regulate proliferation and neoblast fate is still important areas to address. Ptpn11 (Protein tyrosine phosphatase non-receptor type 11), one of PTP (Protein tyrosine phosphatase) family members, plays an important role in cellular processes including cell survival, proliferation, differentiation and apoptosis. Nevertheless, the role of ptpn11 in the planarian regeneration has not been fully studied. In this study, we identify the Djptpn11 gene to observe its function in planarian regeneration. The results reveal that the regeneration is severely inhibited and cause the disorder homeostasis in planarians. Furthermore, the stem cells proliferation and differentiation decreases while the apoptosis increases following Djptpn11 RNAi. At the same time, Djptpn11 affects the expression levels of early wound response genes (Djegr2, Dj1-jun, Djrunt1, Djwnt1 and Djnotum). Djwnt1 and Djnotum are two key Wnt signaling pathway genes and Djptpn11 affects the expression levels of Djwnt1 and Djnotum in the early and late stages of planarian regeneration. In general, Djptpn11 is indispensable for the homeostasis and regeneration of planarian by affecting the stem cells, early wound response genes and the Wnt pathway.
Collapse
|
7
|
Chen X, Hu J. Long Noncoding RNA 3632454L22Rik Contributes to Corneal Epithelial Wound Healing by Sponging miR-181a-5p in Diabetic Mice. Invest Ophthalmol Vis Sci 2021; 62:16. [PMID: 34787641 PMCID: PMC8606839 DOI: 10.1167/iovs.62.14.16] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2021] [Accepted: 10/18/2021] [Indexed: 11/24/2022] Open
Abstract
Purpose This work explores the abnormal expression of long noncoding RNAs (lncRNAs), microRNAs (miRNAs) and messenger RNAs (mRNAs) in diabetic corneal epithelial cells (CECs) and constructs an associated competitive endogenous RNA (ceRNA) network. Moreover, we revealed that Rik may exert advantageous effects on diabetic corneal epithelial wound closure by sponging miR-181a-5p. Methods We obtained the profiles of differentially expressed lncRNAs (DELs) of CECs of type 1 diabetic versus control corneas by microarray and summarized the differentially expressed miRNAs (DEmiRs) and differentially expressed genes (DEGs) data by published literature. Subsequently, the ceRNA network was constructed using bioinformatics analyses. The levels of lncRNA ENSMUST00000153610/3632454L22Rik (Rik) and miR-181a-5p were verified. The localization of Rik was identified with fluorescence in situ hybridization (FISH), and dual-luciferase assays proved the targeted relationship between Rik and miR-181a-5p. Furthermore, we validated the functional impact of Rik in vitro. Results Overall, 111 upregulated and 117 downregulated DELs were detected in diabetic versus control CECs. The level of Rik located in both the cytoplasm and the nucleus was clearly downregulated, whereas miR-181a-5p was upregulated in vitro and in vivo in the diabetic group versus the control group. Rik can act as a ceRNA to bind to miR-181a-5p, thus promoting diabetic corneal epithelial wound healing in vitro. Conclusions This work investigated the expression profile of DELs and constructed ceRNA networks of diabetic CECs for the first time. Furthermore, we revealed that Rik may positively impact diabetic corneal epithelial wound healing by sponging miR-181a-5p, providing a novel potential therapeutic target of diabetic keratopathy (DK).
Collapse
Affiliation(s)
- Xiaxue Chen
- Department of Ophthalmology, Fujian Medical University Union Hospital, Fu Zhou, China
| | - Jianzhang Hu
- Department of Ophthalmology, Fujian Medical University Union Hospital, Fu Zhou, China
| |
Collapse
|
8
|
Liu Y, Di G, Wang Y, Chong D, Cao X, Chen P. Aquaporin 5 Facilitates Corneal Epithelial Wound Healing and Nerve Regeneration by Reactivating Akt Signaling Pathway. THE AMERICAN JOURNAL OF PATHOLOGY 2021; 191:1974-1985. [PMID: 34390680 DOI: 10.1016/j.ajpath.2021.07.010] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/08/2021] [Revised: 07/06/2021] [Accepted: 07/26/2021] [Indexed: 12/13/2022]
Abstract
Aquaporins (AQPs) are normally expressed in the corneal epithelium. The aim of this study was to determine whether AQP5 played a role in corneal epithelial wound healing. AQP5 knockout (AQP5-/-) mice were constructed using CRISPR/Cas9 technology. A corneal wound healing model was performed using epithelial debridement on corneas. The time to corneal epithelial and nerve regeneration was significantly delayed in the AQP5-/- mice. Reduced Ki-67-positive cells and nerve growth factor (NGF) expression were confirmed in the AQP5-/- mice during healing. The epithelial and nerve regeneration rates were significantly promoted in the AQP5-/- mice by treatment with NGF, which was accompanied by recovered levels of phosphorylated Akt. NGF treatment also improved the recovery of corneal nerve fiber density and sensitivity in the AQP5-/- mice. However, the promotion of NGF induced corneal epithelial and nerve regeneration rates, and Akt reactivation was reversed by Akt inhibitor. The significant impairment of corneal wound healing in the AQP5-/- mice resulted from distinct defects in corneal epithelial cell proliferation and nerve regeneration. The results provided evidence for the involvement of aquaporin in cell proliferation and suggested that AQP5 induction could be a potential therapy for accelerating the resurfacing of corneal defects.
Collapse
Affiliation(s)
- Yaning Liu
- Department of Human Anatomy, Histology and Embryology, Qingdao University, Qingdao, China
| | - Guohu Di
- Department of Human Anatomy, Histology and Embryology, Qingdao University, Qingdao, China; Institute of Stem Cell Regeneration Medicine, School of Basic Medicine, Qingdao University, Qingdao, China
| | - Yihui Wang
- Department of Human Anatomy, Histology and Embryology, Qingdao University, Qingdao, China
| | - Daochen Chong
- 971 Hospital of the Chinese People's Liberation Army Navy, Qingdao, China
| | - Xin Cao
- Department of Human Anatomy, Histology and Embryology, Qingdao University, Qingdao, China
| | - Peng Chen
- Department of Human Anatomy, Histology and Embryology, Qingdao University, Qingdao, China; Institute of Stem Cell Regeneration Medicine, School of Basic Medicine, Qingdao University, Qingdao, China.
| |
Collapse
|
9
|
Puri S, Sun M, Mutoji KN, Gesteira TF, Coulson-Thomas VJ. Epithelial Cell Migration and Proliferation Patterns During Initial Wound Closure in Normal Mice and an Experimental Model of Limbal Stem Cell Deficiency. Invest Ophthalmol Vis Sci 2021; 61:27. [PMID: 32790859 PMCID: PMC7441334 DOI: 10.1167/iovs.61.10.27] [Citation(s) in RCA: 22] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
Purpose Establishing the dynamics of corneal wound healing is of vital importance to better understand corneal inflammation, pathology, and corneal regeneration. Numerous studies have made great strides in investigating multiple aspects of corneal wound healing; however, some aspects remain to be elucidated. This study worked toward establishing (1) if epithelial limbal stem cells (LSCs) are necessary for healing all corneal wounds, (2) the mechanism by which epithelial cells migrate toward the wound, and (3) if centrifugal epithelial cell movement exists. Methods To establish different aspects of corneal epithelial wound healing we subjected mice lacking hyaluronan synthase 2 (previously shown to lack LSCs) and wild-type mice to different corneal debridement injury models. Results Our data show that both LSCs and corneal epithelial cells contribute toward closure of corneal wounds. In wild-type mice, removal of the limbal rim delayed closure of 1.5-mm wounds, and not of 0.75-mm wounds, indicating that smaller wounds do not rely on LSCs as do larger wounds. In mice shown to lack LSCs, removal of the limbal rim did not affect wound healing, irrespective of the wound size. Finally, transient amplifying cells and central epithelial cells move toward a central corneal wound in a centripetal manner, whereas central epithelial cells may move in a centrifugal manner to resurface peripheral corneal wounds. Conclusions Our findings show the dimensions of the corneal wound dictate involvement of LSCs. Our data suggest that divergent findings by different groups on the dynamics of wound healing can be in part owing to differences in the wounding models used.
Collapse
Affiliation(s)
- Sudan Puri
- College of Optometry, University of Houston, Houston, Texas, United States
| | - Mingxia Sun
- College of Optometry, University of Houston, Houston, Texas, United States
| | - Kazadi N Mutoji
- College of Optometry, University of Houston, Houston, Texas, United States
| | - Tarsis F Gesteira
- College of Optometry, University of Houston, Houston, Texas, United States
| | | |
Collapse
|