1
|
Mu Y, Zhang N, Wei D, Yang G, Yao L, Xu X, Li Y, Xue J, Zhang Z, Chen T. Müller cells are activated in response to retinal outer nuclear layer degeneration in rats subjected to simulated weightlessness conditions. Neural Regen Res 2025; 20:2116-2128. [PMID: 39254570 DOI: 10.4103/nrr.nrr-d-23-01035] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2023] [Accepted: 01/07/2024] [Indexed: 09/11/2024] Open
Abstract
JOURNAL/nrgr/04.03/01300535-202507000-00032/figure1/v/2024-09-09T124005Z/r/image-tiff A microgravity environment has been shown to cause ocular damage and affect visual acuity, but the underlying mechanisms remain unclear. Therefore, we established an animal model of weightlessness via tail suspension to examine the pathological changes and molecular mechanisms of retinal damage under microgravity. After 4 weeks of tail suspension, there were no notable alterations in retinal function and morphology, while after 8 weeks of tail suspension, significant reductions in retinal function were observed, and the outer nuclear layer was thinner, with abundant apoptotic cells. To investigate the mechanism underlying the degenerative changes that occurred in the outer nuclear layer of the retina, proteomics was used to analyze differentially expressed proteins in rat retinas after 8 weeks of tail suspension. The results showed that the expression levels of fibroblast growth factor 2 (also known as basic fibroblast growth factor) and glial fibrillary acidic protein, which are closely related to Müller cell activation, were significantly upregulated. In addition, Müller cell regeneration and Müller cell gliosis were observed after 4 and 8 weeks, respectively, of simulated weightlessness. These findings indicate that Müller cells play an important regulatory role in retinal outer nuclear layer degeneration during weightlessness.
Collapse
Affiliation(s)
- Yuxue Mu
- Aerospace Clinical Medical Center, School of Aerospace Medicine, Air Force Medical University, Xi'an, Shaanxi Province, China
- Department of Aviation Medicine, Xijing Hospital, Air Force Medical University, Xi'an, Shaanxi Province, China
| | - Ning Zhang
- Department of Emergency Medicine, Wuhan No.1 Hospital, Wuhan, Hubei Province, China
| | - Dongyu Wei
- Aerospace Clinical Medical Center, School of Aerospace Medicine, Air Force Medical University, Xi'an, Shaanxi Province, China
| | - Guoqing Yang
- Aerospace Clinical Medical Center, School of Aerospace Medicine, Air Force Medical University, Xi'an, Shaanxi Province, China
| | - Lilingxuan Yao
- Third Regiment, School of Basic Medicine, Air Force Medical University, Xi'an, Shaanxi Province, China
| | - Xinyue Xu
- Aerospace Clinical Medical Center, School of Aerospace Medicine, Air Force Medical University, Xi'an, Shaanxi Province, China
| | - Yang Li
- Fourth Regiment, School of Basic Medicine, Air Force Medical University, Xi'an, Shaanxi Province, China
| | - Junhui Xue
- Aerospace Clinical Medical Center, School of Aerospace Medicine, Air Force Medical University, Xi'an, Shaanxi Province, China
- Department of Aviation Medicine, Xijing Hospital, Air Force Medical University, Xi'an, Shaanxi Province, China
| | - Zuoming Zhang
- Aerospace Clinical Medical Center, School of Aerospace Medicine, Air Force Medical University, Xi'an, Shaanxi Province, China
| | - Tao Chen
- Aerospace Clinical Medical Center, School of Aerospace Medicine, Air Force Medical University, Xi'an, Shaanxi Province, China
- Department of Aviation Medicine, Xijing Hospital, Air Force Medical University, Xi'an, Shaanxi Province, China
| |
Collapse
|
2
|
Liao Y, Wu M. Comparison of the effects of EGF, FGF-b, and NGF on the proliferation, migration, and reprogramming of primary rat Müller cells. Front Cell Neurosci 2024; 18:1338129. [PMID: 38450284 PMCID: PMC10914979 DOI: 10.3389/fncel.2024.1338129] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2023] [Accepted: 01/31/2024] [Indexed: 03/08/2024] Open
Abstract
Purpose During the healing process of full-thickness macular holes (FTMHs), the closure and recovery of the hole depend on the migration, proliferation, and activation of Müller cells to promote the closure of holes and restoration of the photosensitive layer. In this study, we investigated the ability of the epidermal growth factor (EGF), fibroblast growth factor-basic (FGF-b), and nerve growth factor (NGF) to influence this process by regulating proliferation, migration, and reprogramming of primary rat Müller cells. Methods Cell proliferation was measured using CCK8 [2- (2-Methoxy-4-nitrophenyl)-3- (4-nitrophenyl)-5- (2,4-disulfophenyl)-2H-tetrazolium Sodium Salt] colorimetric assays and EdU [5-Ethynyl-2'-deoxyuridine] assays over 48 h. Cell migration was measured using scratch-wound assays and transwell migration assays over 48 h. In addition, we conducted Western blot assays and immunofluorescence assays on cells that were specially treated for 1, 3, and 5 days for cell reprogramming. The percentage of EdU-positive cells in Nestin-positive have also been tested by co-immunofluorescence (Co-IF) staining. Results EGF and FGF-b significantly promoted the proliferation of Müller cells (p < 0.05) at a concentration of 0-50 ng/mL, but NGF did not (p > 0.05), compared to untreated controls. Exogenous FGF-b and EGF promote the reprogramming of primary rat Müller cells, significantly enhancing the neural stem cell marker Nestin after stimulation on the 1st, 3rd, and 5th days, respectively. The expression of Müller cell marker Vimentin was significantly (p < 0.05) reduced during this period compared to the control group. However, there was no significant difference between the NGF and control groups. Furthermore, the EGF group expressed stronger Nestin expression than the SCM group. The Co-IF staining showed that early 50% of activated cells came from newly proliferating cells on the 5th day. Conclusion These observations suggest that FGF-b can promote the activation of Müller cells in a short time and enhance the possessive features of neural stem cells, while EGF may act for a longer period of time. This may further the understanding of growth factor therapy in treating FTMHs, and Müller glia may be promising candidates for cell replacement therapy.
Collapse
Affiliation(s)
- Yanying Liao
- Hangzhou Medical College, Hangzhou, Zhejiang, China
| | - Miaoqin Wu
- Center for Rehabilitation Medicine, Department of Ophthalmology, Zhejiang Provincial People's Hospital (Affiliated People's Hospital), Hangzhou Medical College, Hangzhou, Zhejiang, China
| |
Collapse
|
3
|
Shigesada N, Shikada N, Shirai M, Toriyama M, Higashijima F, Kimura K, Kondo T, Bessho Y, Shinozuka T, Sasai N. Combination of blockade of endothelin signalling and compensation of IGF1 expression protects the retina from degeneration. Cell Mol Life Sci 2024; 81:51. [PMID: 38252153 PMCID: PMC10803390 DOI: 10.1007/s00018-023-05087-x] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2023] [Revised: 12/01/2023] [Accepted: 12/12/2023] [Indexed: 01/23/2024]
Abstract
Retinitis pigmentosa (RP) and macular dystrophy (MD) cause severe retinal dysfunction, affecting 1 in 4000 people worldwide. This disease is currently assumed to be intractable, because effective therapeutic methods have not been established, regardless of genetic or sporadic traits. Here, we examined a RP mouse model in which the Prominin-1 (Prom1) gene was deficient and investigated the molecular events occurring at the outset of retinal dysfunction. We extracted the Prom1-deficient retina subjected to light exposure for a short time, conducted single-cell expression profiling, and compared the gene expression with and without stimuli. We identified the cells and genes whose expression levels change directly in response to light stimuli. Among the genes altered by light stimulation, Igf1 was decreased in rod photoreceptor cells and astrocytes under the light-stimulated condition. Consistently, the insulin-like growth factor (IGF) signal was weakened in light-stimulated photoreceptor cells. The recovery of Igf1 expression with the adeno-associated virus (AAV) prevented photoreceptor cell death, and its treatment in combination with the endothelin receptor antagonist led to the blockade of abnormal glial activation and the promotion of glycolysis, thereby resulting in the improvement of retinal functions, as assayed by electroretinography. We additionally demonstrated that the attenuation of mammalian/mechanistic target of rapamycin (mTOR), which mediates IGF signalling, leads to complications in maintaining retinal homeostasis. Together, we propose that combinatorial manipulation of distinct mechanisms is useful for the maintenance of the retinal condition.
Collapse
Affiliation(s)
- Naoya Shigesada
- Division of Biological Science, Nara Institute of Science and Technology, Ikoma, 630-0192, Japan
| | - Naoya Shikada
- Division of Biological Science, Nara Institute of Science and Technology, Ikoma, 630-0192, Japan
| | - Manabu Shirai
- Omics Research Center (ORC), National Cerebral and Cardiovascular Center, Suita, Osaka, 564-8565, Japan
| | - Michinori Toriyama
- Department of Biomedical Chemistry, School of Science and Technology, Kwansei Gakuin University, Sanda, 669-1337, Japan
| | - Fumiaki Higashijima
- Department of Ophthalmology, Graduate School of Medicine, Yamaguchi University, Ube, 755-0046, Japan
| | - Kazuhiro Kimura
- Department of Ophthalmology, Graduate School of Medicine, Yamaguchi University, Ube, 755-0046, Japan
| | - Toru Kondo
- Division of Stem Cell Biology, Institute for Genetic Medicine, Hokkaido University, Sapporo, 060-0815, Japan
| | - Yasumasa Bessho
- Division of Biological Science, Nara Institute of Science and Technology, Ikoma, 630-0192, Japan
| | - Takuma Shinozuka
- Division of Biological Science, Nara Institute of Science and Technology, Ikoma, 630-0192, Japan
| | - Noriaki Sasai
- Division of Biological Science, Nara Institute of Science and Technology, Ikoma, 630-0192, Japan.
| |
Collapse
|
4
|
Xiao X, Liao Z, Zou J. Genetic and epigenetic regulators of retinal Müller glial cell reprogramming. ADVANCES IN OPHTHALMOLOGY PRACTICE AND RESEARCH 2023; 3:126-133. [PMID: 37846362 PMCID: PMC10577857 DOI: 10.1016/j.aopr.2023.05.004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 04/13/2023] [Revised: 05/18/2023] [Accepted: 05/29/2023] [Indexed: 10/18/2023]
Abstract
Background Retinal diseases characterized with irreversible loss of retinal nerve cells, such as optic atrophy and retinal degeneration, are the main causes of blindness. Current treatments for these diseases are very limited. An emerging treatment strategy is to induce the reprogramming of Müller glial cells to generate new retinal nerve cells, which could potentially restore vision. Main text Müller glial cells are the predominant glial cells in retinae and play multiple roles to maintain retinal homeostasis. In lower vertebrates, such as in zebrafish, Müller glial cells can undergo cell reprogramming to regenerate new retinal neurons in response to various damage factors, while in mammals, this ability is limited. Interestingly, with proper treatments, Müller glial cells can display the potential for regeneration of retinal neurons in mammalian retinae. Recent studies have revealed that dozens of genetic and epigenetic regulators play a vital role in inducing the reprogramming of Müller glial cells in vivo. This review summarizes these critical regulators for Müller glial cell reprogramming and highlights their differences between zebrafish and mammals. Conclusions A number of factors have been identified as the important regulators in Müller glial cell reprogramming. The early response of Müller glial cells upon acute retinal injury, such as the regulation in the exit from quiescent state, the initiation of reactive gliosis, and the re-entry of cell cycle of Müller glial cells, displays significant difference between mouse and zebrafish, which may be mediated by the diverse regulation of Notch and TGFβ (transforming growth factor-β) isoforms and different chromatin accessibility.
Collapse
Affiliation(s)
- Xueqi Xiao
- Zhejiang Provincial Key Laboratory for Water Environment and Marine Biological Resources Protection, College of Life and Environmental Science, Wenzhou University, Wenzhou, China
| | - Zhiyong Liao
- Zhejiang Provincial Key Laboratory for Water Environment and Marine Biological Resources Protection, College of Life and Environmental Science, Wenzhou University, Wenzhou, China
| | - Jian Zou
- Department of Ophthalmology, The Second Affiliated Hospital of Zhejiang University School of Medicine, Hangzhou, China
- The Institute of Translational Medicine, Zhejiang University, Hangzhou, China
| |
Collapse
|