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Yu X, Zhang M, Zhao H, Gao Y, Deng L, Shi Y, Fan Z. Nanophthalmos-Associated MYRF gene mutation facilitates intraocular inflammation in mice. Int Immunopharmacol 2024; 137:112519. [PMID: 38901241 DOI: 10.1016/j.intimp.2024.112519] [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: 03/20/2024] [Revised: 05/22/2024] [Accepted: 06/16/2024] [Indexed: 06/22/2024]
Abstract
PURPOSE Patients with nanophthalmos might be prone to developing intraocular inflammation following an acute glaucoma attack. Here, we aimed to investigate the role of MYRF in intraocular inflammation by modeling the mutation in mice. METHODS Nanophthalmos frameshift mutation of Myrf was introduced into the mouse genome with the CRISPR-Cas9 system. Signaling pathways in eye tissues were delineated using RNA sequencing and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analysis. Intraocular inflammation was induced by a lipopolysaccharide (LPS) intravitreal injection. Dexamethasone (DEX) was administered systemically and locally a week before the LPS injection. The anterior segment clinical scores of the mice were examined 24 h after the LPS injection. Infiltrating inflammatory cells were evaluated with histopathology and immunofluorescence. The mRNA levels of inflammatory cytokines were quantified with reverse transcription-quantitative PCR (RT-qPCR) and the corresponding protein concentrations using enzyme-linked immunosorbent assay (ELISA). RESULTS Many inflammation-associated signaling pathways were enriched in Myrf mut/+ mice ocular tissues. Clinical scores of Myrf mut/+ mice were significantly higher than those of Myrf +/+ mice 24 h after LPS administration. Histological examination demonstrated high inflammatory cell infiltration in the anterior and vitreous chambers in Myrf mut/+ mice, with numerous CD45+ and CD11b+ inflammatory cells. Moreover, enhanced expression of inflammatory cytokines MCP-1, TGF-β, and IL-1β in eyes and aqueous humor of Myrf mut/+ mice was detected. Remarkably, pretreating Myrf mut/+ mice with DEX relieved the intraocular inflammation. CONCLUSION Nanophthalmos-associated MYRF mutation renders mouse eyes more susceptible to inflammation. Dexamethasone treatment ameliorates the inflammatory response.
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Affiliation(s)
- Xiaowei Yu
- Beijing Tongren Eye Center Research Ward, Beijing Tongren Hospital, Beijing Institute of Ophthalmology, Beijing Ophthalmology & Visual Sciences Key Laboratory, Capital Medical University, Beijing, 100730, China
| | - Miao Zhang
- Beijing Tongren Eye Center Research Ward, Beijing Tongren Hospital, Beijing Institute of Ophthalmology, Beijing Ophthalmology & Visual Sciences Key Laboratory, Capital Medical University, Beijing, 100730, China
| | - Hanxue Zhao
- Beijing Tongren Eye Center Research Ward, Beijing Tongren Hospital, Beijing Institute of Ophthalmology, Beijing Ophthalmology & Visual Sciences Key Laboratory, Capital Medical University, Beijing, 100730, China
| | - Yan Gao
- Beijing Tongren Eye Center Research Ward, Beijing Tongren Hospital, Beijing Institute of Ophthalmology, Beijing Ophthalmology & Visual Sciences Key Laboratory, Capital Medical University, Beijing, 100730, China
| | - Lin Deng
- Beijing Tongren Eye Center Research Ward, Beijing Tongren Hospital, Beijing Institute of Ophthalmology, Beijing Ophthalmology & Visual Sciences Key Laboratory, Capital Medical University, Beijing, 100730, China
| | - Yan Shi
- Beijing Tongren Eye Center Research Ward, Beijing Tongren Hospital, Beijing Institute of Ophthalmology, Beijing Ophthalmology & Visual Sciences Key Laboratory, Capital Medical University, Beijing, 100730, China.
| | - Zhigang Fan
- Beijing Tongren Eye Center Research Ward, Beijing Tongren Hospital, Beijing Institute of Ophthalmology, Beijing Ophthalmology & Visual Sciences Key Laboratory, Capital Medical University, Beijing, 100730, China.
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Brinkmeier ML, Wang SQ, Pittman H, Cheung LY, Prasov L. Myelin regulatory factor ( Myrf ) is a critical early regulator of retinal pigment epithelial development. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.04.26.591281. [PMID: 38746430 PMCID: PMC11092522 DOI: 10.1101/2024.04.26.591281] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/16/2024]
Abstract
Myelin regulatory factor (Myrf) is a critical transcription factor in early retinal and retinal pigment epithelial development, and human variants in MYRF are a cause for nanophthalmos. Single cell RNA sequencing (scRNAseq) was performed on Myrf conditional knockout mice ( Rx>Cre Myrf fl/fl ) at 3 developmental timepoints. Myrf was expressed specifically in the RPE, and expression was abrogated in Rx>Cre Myrf fl/fl eyes. scRNAseq analysis revealed a loss of RPE cells at all timepoints resulting from cell death. GO-term analysis in the RPE revealed downregulation of melanogenesis and anatomic structure morphogenesis pathways, which were supported by electron microscopy and histologic analysis. Novel structural target genes including Ermn and Upk3b , along with macular degeneration and inherited retinal disease genes were identified as downregulated, and a strong upregulation of TGFß/BMP signaling and effectors was observed. Regulon analysis placed Myrf downstream of Pax6 and Mitf and upstream of Sox10 in RPE differentiation. Together, these results suggest a strong role for Myrf in the RPE maturation by regulating melanogenesis, cell survival, and cell structure, in part acting through suppression of TGFß signaling and activation of Sox10 . SUMMARY STATEMENT Myrf regulates RPE development, melanogenesis, and is important for cell structure and survival, in part through regulation of Ermn , Upk3b and Sox10, and BMP/TGFb signaling.
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Wang S, Wang Y, Zou S. A Glance at the Molecules That Regulate Oligodendrocyte Myelination. Curr Issues Mol Biol 2022; 44:2194-2216. [PMID: 35678678 PMCID: PMC9164040 DOI: 10.3390/cimb44050149] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2022] [Revised: 05/10/2022] [Accepted: 05/13/2022] [Indexed: 11/16/2022] Open
Abstract
Oligodendrocyte (OL) myelination is a critical process for the neuronal axon function in the central nervous system. After demyelination occurs because of pathophysiology, remyelination makes repairs similar to myelination. Proliferation and differentiation are the two main stages in OL myelination, and most factors commonly play converse roles in these two stages, except for a few factors and signaling pathways, such as OLIG2 (Oligodendrocyte transcription factor 2). Moreover, some OL maturation gene mutations induce hypomyelination or hypermyelination without an obvious function in proliferation and differentiation. Herein, three types of factors regulating myelination are reviewed in sequence.
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Affiliation(s)
- Shunqi Wang
- Institute of Life Science & School of Life Sciences, Nanchang University, Nanchang 330031, China; (S.W.); (Y.W.)
- School of Basic Medical Sciences, Nanchang University, Nanchang 330031, China
| | - Yingxing Wang
- Institute of Life Science & School of Life Sciences, Nanchang University, Nanchang 330031, China; (S.W.); (Y.W.)
| | - Suqi Zou
- Institute of Life Science & School of Life Sciences, Nanchang University, Nanchang 330031, China; (S.W.); (Y.W.)
- School of Basic Medical Sciences, Nanchang University, Nanchang 330031, China
- Correspondence:
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