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
|
Yin Z, Kang J, Cheng X, Gao H, Huo S, Xu H. Investigating Müller glia reprogramming in mice: a retrospective of the last decade, and a look to the future. Neural Regen Res 2025; 20:946-959. [PMID: 38989930 PMCID: PMC11438324 DOI: 10.4103/nrr.nrr-d-23-01612] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2023] [Accepted: 02/05/2024] [Indexed: 07/12/2024] Open
Abstract
Müller glia, as prominent glial cells within the retina, plays a significant role in maintaining retinal homeostasis in both healthy and diseased states. In lower vertebrates like zebrafish, these cells assume responsibility for spontaneous retinal regeneration, wherein endogenous Müller glia undergo proliferation, transform into Müller glia-derived progenitor cells, and subsequently regenerate the entire retina with restored functionality. Conversely, Müller glia in the mouse and human retina exhibit limited neural reprogramming. Müller glia reprogramming is thus a promising strategy for treating neurodegenerative ocular disorders. Müller glia reprogramming in mice has been accomplished with remarkable success, through various technologies. Advancements in molecular, genetic, epigenetic, morphological, and physiological evaluations have made it easier to document and investigate the Müller glia programming process in mice. Nevertheless, there remain issues that hinder improving reprogramming efficiency and maturity. Thus, understanding the reprogramming mechanism is crucial toward exploring factors that will improve Müller glia reprogramming efficiency, and for developing novel Müller glia reprogramming strategies. This review describes recent progress in relatively successful Müller glia reprogramming strategies. It also provides a basis for developing new Müller glia reprogramming strategies in mice, including epigenetic remodeling, metabolic modulation, immune regulation, chemical small-molecules regulation, extracellular matrix remodeling, and cell-cell fusion, to achieve Müller glia reprogramming in mice.
Collapse
Affiliation(s)
- Zhiyuan Yin
- Key Lab of Visual Damage and Regeneration & Restoration of Chongqing, Southwest Eye Hospital, Southwest Hospital, Third Military Medical University (Army Medical University), Chongqing, China
| | | | | | | | | | | |
Collapse
|
3
|
Hernández-Núñez I, Clark BS. Experimental Framework for Assessing Mouse Retinal Regeneration Through Single-Cell RNA-Sequencing. Methods Mol Biol 2025; 2848:117-134. [PMID: 39240520 DOI: 10.1007/978-1-0716-4087-6_8] [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: 09/07/2024]
Abstract
Retinal degenerative diseases including age-related macular degeneration and glaucoma are estimated to currently affect more than 14 million people in the United States, with an increased prevalence of retinal degenerations in aged individuals. An expanding aged population who are living longer forecasts an increased prevalence and economic burden of visual impairments. Improvements to visual health and treatment paradigms for progressive retinal degenerations slow vision loss. However, current treatments fail to remedy the root cause of visual impairments caused by retinal degenerations-loss of retinal neurons. Stimulation of retinal regeneration from endogenous cellular sources presents an exciting treatment avenue for replacement of lost retinal cells. In multiple species including zebrafish and Xenopus, Müller glial cells maintain a highly efficient regenerative ability to reconstitute lost cells throughout the organism's lifespan, highlighting potential therapeutic avenues for stimulation of retinal regeneration in humans. Here, we describe how the application of single-cell RNA-sequencing (scRNA-seq) has enhanced our understanding of Müller glial cell-derived retinal regeneration, including the characterization of gene regulatory networks that facilitate/inhibit regenerative responses. Additionally, we provide a validated experimental framework for cellular preparation of mouse retinal cells as input into scRNA-seq experiments, including insights into experimental design and analyses of resulting data.
Collapse
Affiliation(s)
- Ismael Hernández-Núñez
- John F Hardesty, MD Department of Ophthalmology and Visual Sciences, Washington University School of Medicine, St. Louis, MO, USA
| | - Brian S Clark
- John F Hardesty, MD Department of Ophthalmology and Visual Sciences, Washington University School of Medicine, St. Louis, MO, USA.
- Department of Developmental Biology, Washington University School of Medicine, St. Louis, MO, USA.
| |
Collapse
|
4
|
Taylor O, DeGroff N, El-Hodiri H, Gao C, Fischer AJ. Sphingosine-1-phosphate signaling regulates the ability of Müller glia to become neurogenic, proliferating progenitor-like cells. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.08.06.606815. [PMID: 39149287 PMCID: PMC11326190 DOI: 10.1101/2024.08.06.606815] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Indexed: 08/17/2024]
Abstract
The purpose of these studies is to investigate how Sphingosine-1-phosphate (S1P) signaling regulates glial phenotype, dedifferentiation of Müller glia (MG), reprogramming into proliferating MG-derived progenitor cells (MGPCs), and neuronal differentiation of the progeny of MGPCs. We found that S1P-related genes are highly expressed by retinal neurons and glia, and levels of expression were dynamically regulated following retinal damage. S1PR1 is highly expressed by resting MG and is rapidly downregulated following acute retinal damage. Drug treatments that activate S1PR1 or increase levels of S1P suppressed the formation of MGPCs, whereas treatments that inhibit S1PR1 or decreased levels of S1P stimulated the formation of MGPCs. Inhibition of S1PR1 or SPHK1 significantly enhanced the neuronal differentiation of the progeny of MGPCs. Further, ablation of microglia from the retina, wherein the formation of MGPCs in damaged retinas is impaired, has a significant impact upon expression patterns of S1P-related genes in MG. Inhibition of S1PR1 and SPHK1 partially rescued the formation of MGPCs in damaged retinas missing microglia. Finally, we show that TGFβ/Smad3 signaling in the resting retina maintains S1PR1 expression in MG. We conclude that the S1P signaling is dynamically regulated in MG and MGPCs and activation of S1P signaling depends, in part, on signals produced by reactive microglia.
Collapse
Affiliation(s)
- Olivia Taylor
- Department of Neuroscience, College of Medicine, The Ohio State University, Columbus, OH 43210, USA
| | - Nicholas DeGroff
- Department of Neuroscience, College of Medicine, The Ohio State University, Columbus, OH 43210, USA
| | - Heithem El-Hodiri
- Department of Neuroscience, College of Medicine, The Ohio State University, Columbus, OH 43210, USA
| | - Chengyu Gao
- Campus Chemical Instrument Center, Mass Spectrometry & Proteomics Facility, The Ohio State University, Columbus, OH 43210, USA
| | - Andy J. Fischer
- Department of Neuroscience, College of Medicine, The Ohio State University, Columbus, OH 43210, USA
| |
Collapse
|
5
|
Abdulmalek S, Connole LM, O'Sullivan NC, Beyna M, Pangalos MN, von Schack D, Ring RH, Murphy KJ. Midkine is upregulated in the hippocampus following both spatial and olfactory reward association learning and enhances memory. J Neurochem 2024; 168:2832-2847. [PMID: 39361112 DOI: 10.1111/jnc.16151] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2023] [Revised: 06/03/2024] [Accepted: 06/05/2024] [Indexed: 10/06/2024]
Abstract
Hippocampal neuronal plasticity is a fundamental process underpinning learning and memory formation and requiring elaborate molecular mechanisms that result in the dynamic remodelling of synaptic connectivity. The neurotrophic properties of midkine (Mdk) have been implicated in the development and repair of the nervous system, while Mdk knockout resulted in deficits in the formation of certain types of memory. The role of Mdk in the process of memory-associated neuronal plasticity, however, remains poorly understood. We investigated the learning-induced regulation of Mdk in spatial navigation and association learning using the water maze and the odour reward association learning paradigms, characterising a temporal profile of Mdk protein expression post-learning. Both learning events revealed similar patterns of upregulation of expression of the protein in the rat hippocampal dentate gyrus, which were rapid and transient. Moreover, administration of recombinant Mdk during the endogenous Mdk upregulation following learning enhanced memory in the water maze task revealing a pro-cognitive action of Mdk. We further show that, within the adult hippocampus, Mdk mRNA is predominantly expressed in granular and pyramidal neurons and that hippocampal neuronal Mdk expression is regulated by the canonical plasticity-associated neurotransmitter glutamate. Finally, we confirm that the positive action of Mdk on neurite outgrowth previously noted in cortical and cerebellar neurons extends to hippocampal neurons. Together, our findings suggest a role for Mdk in glutamate-mediated hippocampal neuronal plasticity important for long-term memory consolidation.
Collapse
Affiliation(s)
- Sarah Abdulmalek
- Neurotherapeutics Research Group, UCD School of Biomolecular and Biomedical Science, UCD Conway Institute, University College Dublin, Dublin, Ireland
| | - Laura M Connole
- Neurotherapeutics Research Group, UCD School of Biomolecular and Biomedical Science, UCD Conway Institute, University College Dublin, Dublin, Ireland
| | - Niamh C O'Sullivan
- Neurotherapeutics Research Group, UCD School of Biomolecular and Biomedical Science, UCD Conway Institute, University College Dublin, Dublin, Ireland
| | - Mercedes Beyna
- Inflammation Research Unit, Pfizer Worldwide Research & Development, Cambridge, Massachusetts, USA
| | | | - David von Schack
- Inflammation Research Unit, Pfizer Worldwide Research & Development, Cambridge, Massachusetts, USA
| | | | - Keith J Murphy
- Neurotherapeutics Research Group, UCD School of Biomolecular and Biomedical Science, UCD Conway Institute, University College Dublin, Dublin, Ireland
| |
Collapse
|
6
|
Liu H, Lu S, Chen M, Gao N, Yang Y, Hu H, Ren Q, Liu X, Chen H, Zhu Q, Li S, Su J. Towards Stem/Progenitor Cell-Based Therapies for Retinal Degeneration. Stem Cell Rev Rep 2024; 20:1459-1479. [PMID: 38809490 DOI: 10.1007/s12015-024-10740-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 05/21/2024] [Indexed: 05/30/2024]
Abstract
Retinal degeneration (RD) is a leading cause of blindness worldwide and includes conditions such as retinitis pigmentosa (RP), age-related macular degeneration (AMD), and Stargardt's disease (STGD). These diseases result in the permanent loss of vision due to the progressive and irreversible degeneration of retinal cells, including photoreceptors (PR) and the retinal pigment epithelium (RPE). The adult human retina has limited abilities to regenerate and repair itself, making it challenging to achieve complete self-replenishment and functional repair of retinal cells. Currently, there is no effective clinical treatment for RD. Stem cell therapy, which involves transplanting exogenous stem cells such as retinal progenitor cells (RPCs), embryonic stem cells (ESCs), induced pluripotent stem cells (iPSCs), and mesenchymal stem cells (MSCs), or activating endogenous stem cells like Müller Glia (MG) cells, holds great promise for regenerating and repairing retinal cells in the treatment of RD. Several preclinical and clinical studies have shown the potential of stem cell-based therapies for RD. However, the clinical translation of these therapies for the reconstruction of substantial vision still faces significant challenges. This review provides a comprehensive overview of stem/progenitor cell-based therapy strategies for RD, summarizes recent advances in preclinical studies and clinical trials, and highlights the major challenges in using stem/progenitor cell-based therapies for RD.
Collapse
Affiliation(s)
- Hui Liu
- National Engineering Research Center of Ophthalmology and Optometry, Eye Hospital, Wenzhou Medical University, Wenzhou, 325027, China
- State Key Laboratory of Ophthalmology, Optometry and Visual Science, Eye Hospital, Wenzhou Medical University, Wenzhou, 325027, China
| | - Shuaiyan Lu
- National Engineering Research Center of Ophthalmology and Optometry, Eye Hospital, Wenzhou Medical University, Wenzhou, 325027, China
- State Key Laboratory of Ophthalmology, Optometry and Visual Science, Eye Hospital, Wenzhou Medical University, Wenzhou, 325027, China
| | - Ming Chen
- National Engineering Research Center of Ophthalmology and Optometry, Eye Hospital, Wenzhou Medical University, Wenzhou, 325027, China
- State Key Laboratory of Ophthalmology, Optometry and Visual Science, Eye Hospital, Wenzhou Medical University, Wenzhou, 325027, China
| | - Na Gao
- National Engineering Research Center of Ophthalmology and Optometry, Eye Hospital, Wenzhou Medical University, Wenzhou, 325027, China
- State Key Laboratory of Ophthalmology, Optometry and Visual Science, Eye Hospital, Wenzhou Medical University, Wenzhou, 325027, China
| | - Yuhe Yang
- National Engineering Research Center of Ophthalmology and Optometry, Eye Hospital, Wenzhou Medical University, Wenzhou, 325027, China
- State Key Laboratory of Ophthalmology, Optometry and Visual Science, Eye Hospital, Wenzhou Medical University, Wenzhou, 325027, China
| | - Huijuan Hu
- National Engineering Research Center of Ophthalmology and Optometry, Eye Hospital, Wenzhou Medical University, Wenzhou, 325027, China
- State Key Laboratory of Ophthalmology, Optometry and Visual Science, Eye Hospital, Wenzhou Medical University, Wenzhou, 325027, China
| | - Qing Ren
- National Engineering Research Center of Ophthalmology and Optometry, Eye Hospital, Wenzhou Medical University, Wenzhou, 325027, China
- State Key Laboratory of Ophthalmology, Optometry and Visual Science, Eye Hospital, Wenzhou Medical University, Wenzhou, 325027, China
| | - Xiaoyu Liu
- National Engineering Research Center of Ophthalmology and Optometry, Eye Hospital, Wenzhou Medical University, Wenzhou, 325027, China
- State Key Laboratory of Ophthalmology, Optometry and Visual Science, Eye Hospital, Wenzhou Medical University, Wenzhou, 325027, China
| | - Hongxu Chen
- National Engineering Research Center of Ophthalmology and Optometry, Eye Hospital, Wenzhou Medical University, Wenzhou, 325027, China
- State Key Laboratory of Ophthalmology, Optometry and Visual Science, Eye Hospital, Wenzhou Medical University, Wenzhou, 325027, China
| | - Qunyan Zhu
- Wenzhou Institute, University of Chinese Academy of Sciences, Wenzhou, Zhejiang, 325011, China
| | - Shasha Li
- National Engineering Research Center of Ophthalmology and Optometry, Eye Hospital, Wenzhou Medical University, Wenzhou, 325027, China.
- State Key Laboratory of Ophthalmology, Optometry and Visual Science, Eye Hospital, Wenzhou Medical University, Wenzhou, 325027, China.
- Oujiang Laboratory (Zhejiang Lab for Regenerative Medicine, Vision and Brain Health), Wenzhou, 325001, China.
| | - Jianzhong Su
- National Engineering Research Center of Ophthalmology and Optometry, Eye Hospital, Wenzhou Medical University, Wenzhou, 325027, China.
- State Key Laboratory of Ophthalmology, Optometry and Visual Science, Eye Hospital, Wenzhou Medical University, Wenzhou, 325027, China.
- Wenzhou Institute, University of Chinese Academy of Sciences, Wenzhou, Zhejiang, 325011, China.
- Oujiang Laboratory (Zhejiang Lab for Regenerative Medicine, Vision and Brain Health), Wenzhou, 325001, China.
| |
Collapse
|
7
|
Taylor OB, Patel SP, Hawthorn EC, El-Hodiri HM, Fischer AJ. ID factors regulate the ability of Müller glia to become proliferating neurogenic progenitor-like cells. Glia 2024; 72:1236-1258. [PMID: 38515287 PMCID: PMC11334223 DOI: 10.1002/glia.24523] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2023] [Revised: 02/26/2024] [Accepted: 02/28/2024] [Indexed: 03/23/2024]
Abstract
The purpose of this study was to investigate how ID factors regulate the ability of Müller glia (MG) to reprogram into proliferating MG-derived progenitor cells (MGPCs) in the chick retina. We found that ID1 is transiently expressed by maturing MG (mMG), whereas ID4 is maintained in mMG in embryonic retinas. In mature retinas, ID4 was prominently expressed by resting MG, but following retinal damage ID4 was rapidly upregulated and then downregulated in MGPCs. By contrast, ID1, ID2, and ID3 were low in resting MG and then upregulated in MGPCs. Inhibition of ID factors following retinal damage decreased numbers of proliferating MGPCs. Inhibition of IDs, after MGPC proliferation, significantly increased numbers of progeny that differentiated as neurons. In damaged or undamaged retinas inhibition of IDs increased levels of p21Cip1 in MG. In response to damage or insulin+FGF2 levels of CDKN1A message and p21Cip1 protein were decreased, absent in proliferating MGPCs, and elevated in MG returning to a resting phenotype. Inhibition of notch- or gp130/Jak/Stat-signaling in damaged retinas increased levels of ID4 but not p21Cip1 in MG. Although ID4 is the predominant isoform expressed by MG in the chick retina, id1 and id2a are predominantly expressed by resting MG and downregulated in activated MG and MGPCs in zebrafish retinas. We conclude that ID factors have a significant impact on regulating the responses of MG to retinal damage, controlling the ability of MG to proliferate by regulating levels of p21Cip1, and suppressing the neurogenic potential of MGPCs.
Collapse
Affiliation(s)
- Olivia B. Taylor
- Department of Neuroscience, College of Medicine, The Ohio State University, Columbus, OH
| | - Snehal P. Patel
- Department of Neuroscience, College of Medicine, The Ohio State University, Columbus, OH
| | - Evan C. Hawthorn
- Department of Neuroscience, College of Medicine, The Ohio State University, Columbus, OH
| | - Heithem M. El-Hodiri
- Department of Neuroscience, College of Medicine, The Ohio State University, Columbus, OH
| | - Andy J. Fischer
- Department of Neuroscience, College of Medicine, The Ohio State University, Columbus, OH
| |
Collapse
|
8
|
Kelly LE, El-Hodiri HM, Crider A, Fischer AJ. Protein phosphatases regulate the formation of Müller glia-derived progenitor cells in the chick retina. Mol Cell Neurosci 2024; 129:103932. [PMID: 38679247 PMCID: PMC11362962 DOI: 10.1016/j.mcn.2024.103932] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2024] [Revised: 03/26/2024] [Accepted: 04/18/2024] [Indexed: 05/01/2024] Open
Abstract
Different kinase-dependent cell signaling pathways are known to play important roles in glia-mediated neuroprotection and reprogramming of Müller glia (MG) into Müller glia-derived progenitor cells (MGPCs) in the retina. However, very little is known about the phosphatases that regulate kinase-dependent signaling in MG. Using single-cell RNA-sequencing (scRNA-seq) databases, we investigated patterns of expression of Dual Specificity Phosphatases (DUSP1/6) and other protein phosphatases in normal and damaged chick retinas. We found that DUSP1, DUSP6, PPP3CB, PPP3R1 and PPPM1A/B/D/E/G are widely expressed by many types of retinal neurons and are dynamically expressed by MG and MGPCs in retinas during the process of reprogramming. We find that inhibition of DUSP1/6 and PP2C phosphatases enhances the formation of proliferating MGPCs in damaged retinas and in retinas treated with insulin and FGF2 in the absence of damage. By contrast, inhibition of PP2B phosphatases suppressed the formation of proliferating MGPCs, but increased numbers of proliferating MGPCs in undamaged retinas treated with insulin and FGF2. In damaged retinas, inhibition of DUSP1/6 increased levels of pERK1/2 and cFos in MG whereas inhibition of PP2B's decreased levels of pStat3 and pS6 in MG. Analyses of scRNA-seq libraries identified numerous differentially activated gene modules in MG in damaged retinas versus MG in retinas treated with insulin+FGF2 suggesting significant differences in kinase-dependent signaling pathways that converge on the formation of MGPCs. Inhibition of phosphatases had no significant effects upon numbers of dying cells in damaged retinas. We conclude that the activity of different protein phosphatases acting through retinal neurons and MG "fine-tune" the cell signaling responses of MG in damaged retinas and during the reprogramming of MG into MGPCs.
Collapse
Affiliation(s)
- Lisa E Kelly
- Department of Neuroscience, College of Medicine, The Ohio State University, Columbus, OH, USA
| | - Heithem M El-Hodiri
- Department of Neuroscience, College of Medicine, The Ohio State University, Columbus, OH, USA
| | - Andrew Crider
- Department of Neuroscience, College of Medicine, The Ohio State University, Columbus, OH, USA
| | - Andy J Fischer
- Department of Neuroscience, College of Medicine, The Ohio State University, Columbus, OH, USA.
| |
Collapse
|
9
|
Eskandari-Sedighi G, Crichton M, Zia S, Gomez-Cardona E, Cortez LM, Patel ZH, Takahashi-Yamashiro K, St Laurent CD, Sidhu G, Sarkar S, Aghanya V, Sim VL, Tan Q, Julien O, Plemel JR, Macauley MS. Alzheimer's disease associated isoforms of human CD33 distinctively modulate microglial cell responses in 5XFAD mice. Mol Neurodegener 2024; 19:42. [PMID: 38802940 PMCID: PMC11129479 DOI: 10.1186/s13024-024-00734-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2023] [Accepted: 05/16/2024] [Indexed: 05/29/2024] Open
Abstract
Microglia play diverse pathophysiological roles in Alzheimer's disease (AD), with genetic susceptibility factors skewing microglial cell function to influence AD risk. CD33 is an immunomodulatory receptor associated with AD susceptibility through a single nucleotide polymorphism that modulates mRNA splicing, skewing protein expression from a long protein isoform (CD33M) to a short isoform (CD33m). Understanding how human CD33 isoforms differentially impact microglial cell function in vivo has been challenging due to functional divergence of CD33 between mice and humans. We address this challenge by studying transgenic mice expressing either of the human CD33 isoforms crossed with the 5XFAD mouse model of amyloidosis and find that human CD33 isoforms have opposing effects on the response of microglia to amyloid-β (Aβ) deposition. Mice expressing CD33M have increased Aβ levels, more diffuse plaques, fewer disease-associated microglia, and more dystrophic neurites compared to 5XFAD control mice. Conversely, CD33m promotes plaque compaction and microglia-plaque contacts, and minimizes neuritic plaque pathology, highlighting an AD protective role for this isoform. Protective phenotypes driven by CD33m are detected at an earlier timepoint compared to the more aggressive pathology in CD33M mice that appears at a later timepoint, suggesting that CD33m has a more prominent impact on microglia cell function at earlier stages of disease progression. In addition to divergent roles in modulating phagocytosis, scRNAseq and proteomics analyses demonstrate that CD33m+ microglia upregulate nestin, an intermediate filament involved in cell migration, at plaque contact sites. Overall, our work provides new functional insights into how CD33, as a top genetic susceptibility factor for AD, modulates microglial cell function.
Collapse
Affiliation(s)
| | | | - Sameera Zia
- Division of Neurology, Department of Medicine, University of Alberta, Edmonton, Canada
| | | | - Leonardo M Cortez
- Division of Neurology, Department of Medicine, University of Alberta, Edmonton, Canada
- Centre for Prions and Protein Folding Diseases, University of Alberta, Edmonton, Canada
- Neuroscience and Mental Health Institute, University of Alberta, Edmonton, Canada
| | - Zain H Patel
- Department of Cell Biology, University of Alberta, Edmonton, Canada
| | | | | | - Gaurav Sidhu
- Department of Chemistry, University of Alberta, Edmonton, Canada
| | - Susmita Sarkar
- Department of Chemistry, University of Alberta, Edmonton, Canada
| | - Vivian Aghanya
- Department of Chemistry, University of Alberta, Edmonton, Canada
| | - Valerie L Sim
- Division of Neurology, Department of Medicine, University of Alberta, Edmonton, Canada
- Centre for Prions and Protein Folding Diseases, University of Alberta, Edmonton, Canada
- Neuroscience and Mental Health Institute, University of Alberta, Edmonton, Canada
| | - Qiumin Tan
- Department of Cell Biology, University of Alberta, Edmonton, Canada
| | - Olivier Julien
- Department of Biochemistry, University of Alberta, Edmonton, Canada
- Neuroscience and Mental Health Institute, University of Alberta, Edmonton, Canada
| | - Jason R Plemel
- Division of Neurology, Department of Medicine, University of Alberta, Edmonton, Canada
- Neuroscience and Mental Health Institute, University of Alberta, Edmonton, Canada
- Department of Medical Microbiology and Immunology, University of Alberta, Edmonton, Canada
| | - Matthew S Macauley
- Department of Chemistry, University of Alberta, Edmonton, Canada.
- Neuroscience and Mental Health Institute, University of Alberta, Edmonton, Canada.
- Department of Medical Microbiology and Immunology, University of Alberta, Edmonton, Canada.
| |
Collapse
|
10
|
Deng X, Mo Y, Zhu X. Deciphering Müller cell heterogeneity signatures in diabetic retinopathy across species: an integrative single-cell analysis. Eur J Med Res 2024; 29:265. [PMID: 38698486 PMCID: PMC11067085 DOI: 10.1186/s40001-024-01847-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2024] [Accepted: 04/17/2024] [Indexed: 05/05/2024] Open
Abstract
Diabetic retinopathy (DR), a leading cause of visual impairment, demands a profound comprehension of its cellular mechanisms to formulate effective therapeutic strategies. Our study presentes a comprehensive single-cell analysis elucidating the intricate landscape of Müller cells within DR, emphasizing their nuanced involvement. Utilizing scRNA-seq data from both Sprague-Dawley rat models and human patients, we delineated distinct Müller cell clusters and their corresponding gene expression profiles. These findings were further validated through differential gene expression analysis utilizing human transcriptomic data. Notably, certain Müller cell clusters displayed upregulation of the Rho gene, implying a phagocytic response to damaged photoreceptors within the DR microenvironment. This phenomenon was consistently observed across species. Additionally, the co-expression patterns of RHO and PDE6G within Müller cell clusters provided compelling evidence supporting their potential role in maintaining retinal integrity during DR. Our results offer novel insights into the cellular dynamics of DR and underscore Müller cells as promising therapeutic targets for preserving vision in retinal disorders induced by diabetes.
Collapse
Affiliation(s)
- Xiyuan Deng
- Chengdu University of Traditional Chinese Medicine, Chengdu, China
| | - Ya Mo
- Hospital of Chengdu University of Traditional Chinese Medicine, Chengdu, China.
| | - Xiuying Zhu
- Chengdu University of Traditional Chinese Medicine, Chengdu, China
| |
Collapse
|
11
|
Wang D, Pu Y, Tan S, Wang X, Zeng L, Lei J, Gao X, Li H. Identification of immune-related biomarkers for glaucoma using gene expression profiling. Front Genet 2024; 15:1366453. [PMID: 38694874 PMCID: PMC11062407 DOI: 10.3389/fgene.2024.1366453] [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: 01/06/2024] [Accepted: 04/03/2024] [Indexed: 05/04/2024] Open
Abstract
Introduction: Glaucoma, a principal cause of irreversible vision loss, is characterized by intricate optic neuropathy involving significant immune mechanisms. This study seeks to elucidate the molecular and immune complexities of glaucoma, aiming to improve our understanding of its pathogenesis. Methods: Gene expression profiles from glaucoma patients were analyzed to identify immune-related differentially expressed genes (DEGs). Techniques used were weighted gene co-expression network analysis (WGCNA) for network building, machine learning algorithms for biomarker identification, establishment of subclusters related to immune reactions, and single-sample gene set enrichment analysis (ssGSEA) to explore hub genes' relationships with immune cell infiltration and immune pathway activation. Validation was performed using an NMDA-induced excitotoxicity model and RT-qPCR for hub gene expression measurement. Results: The study identified 409 DEGs differentiating healthy individuals from glaucoma patients, highlighting the immune response's significance in disease progression. Immune cell infiltration analysis revealed elevated levels of activated dendritic cells, natural killer cells, monocytes, and immature dendritic cells in glaucoma samples. Three hub genes, CD40LG, TEK, and MDK, were validated as potential diagnostic biomarkers for high-risk glaucoma patients, showing increased expression in the NMDA-induced excitotoxicity model. Discussion: The findings propose the three identified immune-related genes (IRGs) as novel diagnostic markers for glaucoma, offering new insights into the disease's pathogenesis and potential therapeutic targets. The strong correlation between these IRGs and immune responses underscores the intricate role of immunity in glaucoma, suggesting a shift in the approach to its diagnosis and treatment.
Collapse
Affiliation(s)
- Dangdang Wang
- Department of Ophthalmology, The First Affiliated Hospital of Chongqing Medical University, Chongqing, China
- Chongqing Key Laboratory for the Prevention and Treatment of Major Blinding Eye Diseases, Chongqing Eye Institute, Chongqing Branch of National Clinical Research Center for Ocular Diseases, Chongqing, China
| | - Yanyu Pu
- Department of Ophthalmology, The First Affiliated Hospital of Chongqing Medical University, Chongqing, China
- Chongqing Key Laboratory for the Prevention and Treatment of Major Blinding Eye Diseases, Chongqing Eye Institute, Chongqing Branch of National Clinical Research Center for Ocular Diseases, Chongqing, China
| | - Sisi Tan
- Department of Ophthalmology, The First Affiliated Hospital of Chongqing Medical University, Chongqing, China
- Chongqing Key Laboratory for the Prevention and Treatment of Major Blinding Eye Diseases, Chongqing Eye Institute, Chongqing Branch of National Clinical Research Center for Ocular Diseases, Chongqing, China
| | - Xiaochen Wang
- Department of Ophthalmology, The First Affiliated Hospital of Chongqing Medical University, Chongqing, China
- Chongqing Key Laboratory for the Prevention and Treatment of Major Blinding Eye Diseases, Chongqing Eye Institute, Chongqing Branch of National Clinical Research Center for Ocular Diseases, Chongqing, China
| | - Lihong Zeng
- Department of Ophthalmology, The First Affiliated Hospital of Chongqing Medical University, Chongqing, China
- Chongqing Key Laboratory for the Prevention and Treatment of Major Blinding Eye Diseases, Chongqing Eye Institute, Chongqing Branch of National Clinical Research Center for Ocular Diseases, Chongqing, China
| | - Junqin Lei
- Department of Ophthalmology, The First Affiliated Hospital of Chongqing Medical University, Chongqing, China
- Chongqing Key Laboratory for the Prevention and Treatment of Major Blinding Eye Diseases, Chongqing Eye Institute, Chongqing Branch of National Clinical Research Center for Ocular Diseases, Chongqing, China
| | - Xi Gao
- Department of Ophthalmology, The First Affiliated Hospital of Chongqing Medical University, Chongqing, China
- Chongqing Key Laboratory for the Prevention and Treatment of Major Blinding Eye Diseases, Chongqing Eye Institute, Chongqing Branch of National Clinical Research Center for Ocular Diseases, Chongqing, China
| | - Hong Li
- Department of Ophthalmology, The First Affiliated Hospital of Chongqing Medical University, Chongqing, China
- Chongqing Key Laboratory for the Prevention and Treatment of Major Blinding Eye Diseases, Chongqing Eye Institute, Chongqing Branch of National Clinical Research Center for Ocular Diseases, Chongqing, China
| |
Collapse
|
12
|
Hamadmad S, Heisler-Taylor T, Goswami S, Hawthorn E, Chaurasia S, Martini D, Summitt D, Zaatari A, Urbanski EG, Bernstein K, Racine J, Satoskar A, El-Hodiri HM, Fischer AJ, Cebulla CM. Ibudilast Protects Retinal Bipolar Cells from Excitotoxic Retinal Damage and Activates the mTOR Pathway. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.03.18.585556. [PMID: 38562805 PMCID: PMC10983953 DOI: 10.1101/2024.03.18.585556] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/04/2024]
Abstract
Ibudilast, an inhibitor of macrophage migration inhibitory factor (MIF) and phosphodiesterase (PDE), has been recently shown to have neuroprotective effects in a variety of neurologic diseases. We utilize a chick excitotoxic retinal damage model to investigate ibudilast's potential to protect retinal neurons. Using single cell RNA-sequencing (scRNA-seq), we find that MIF, putative MIF receptors CD74 and CD44, and several PDEs are upregulated in different retinal cells during damage. Intravitreal ibudilast is well tolerated in the eye and causes no evidence of toxicity. Ibudilast effectively protects neurons in the inner nuclear layer from NMDA-induced cell death, restores retinal layer thickness on spectral domain optical coherence tomography, and preserves retinal neuron function, particularly for the ON bipolar cells, as assessed by electroretinography. PDE inhibition seems essential for ibudilast's neuroprotection, as AV1013, the analogue that lacks PDE inhibitor activity, is ineffective. scRNA-seq analysis reveals upregulation of multiple signaling pathways, including mTOR, in damaged Müller glia (MG) with ibudilast treatment compared to AV1013. Components of mTORC1 and mTORC2 are upregulated in both bipolar cells and MG with ibudilast. The mTOR inhibitor rapamycin blocked accumulation of pS6 but did not reduce TUNEL positive dying cells. Additionally, through ligand-receptor interaction analysis, crosstalk between bipolar cells and MG may be important for neuroprotection. We have identified several paracrine signaling pathways that are known to contribute to cell survival and neuroprotection and might play essential roles in ibudilast function. These findings highlight ibudilast's potential to protect inner retinal neurons during damage and show promise for future clinical translation.
Collapse
|
13
|
Zhu T, Li Y, Zhu L, Xu J, Feng Z, Chen H, Shi S, Liu C, Ou Q, Gao F, Zhang J, Jin C, Xu J, Li J, Zhang J, Bi Y, Xu GT, Wang J, Tian H, Lu L. GMFB/AKT/TGF-β3 in Müller cells mediated early retinal degeneration in a streptozotocin-induced rat diabetes model. Glia 2024; 72:504-528. [PMID: 37904673 DOI: 10.1002/glia.24486] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2023] [Revised: 09/14/2023] [Accepted: 10/16/2023] [Indexed: 11/01/2023]
Abstract
Retinal degeneration, characterized by Müller cell gliosis and photoreceptor apoptosis, is considered an early event in diabetic retinopathy (DR). Our previous study proposed that GMFB may mediate diabetic retinal degeneration. This study identified GMFB as a sensitive and functional gliosis marker for DR. Compared to the wild type (WT) group, Gmfb knockout (KO) significantly improved visual function, attenuated gliosis, reduced the apoptosis of neurons, and decreased the mRNA levels of tumor necrosis factor α (Tnf-α) and interleukin-1β (Il-1β) in diabetic retinas. Tgf-β3 was enriched by hub genes using RNA sequencing in primary WT and KO Müller cells. Gmfb KO significantly upregulated the transforming growth factor (TGF)-β3 protein level via the AKT pathway. The protective effect of TGF-β3 in the vitreous resulted in significantly improved visual function and decreased the number of apoptotic cells in the diabetic retina. The protection of Gmfb KO in primary Müller cells against high glucose (HG)-induced photoreceptor apoptosis was partially counteracted by TGF-β3 antibody and administration of TGFBR1/2 inhibitors. Nuclear receptor subfamily 3 group C member 1 (NR3C1) binds to the promoter region of Gmfb and regulates Gmfb mRNA at the transcriptional level. NR3C1 was increased in the retinas of early diabetic rats but decreased in the retinas of late diabetic rats. N'-[(1E)-(3-Methoxyphenyl)Methylene]-3-Methyl-1H-Pyrazole-5-Carbohydrazide (DS-5) was identified as an inhibitor of GMFB, having a protective role in DR. We demonstrated that GMFB/AKT/TGF-β3 mediated early diabetic retinal degeneration in diabetic rats. This study provides a novel therapeutic strategy for treating retinal degeneration in patients with DR.
Collapse
Affiliation(s)
- Tong Zhu
- Department of Ophthalmology of Shanghai Tongji Hospital, Laboratory of Clinical Visual Science of Tongji Eye Institute, School of Medicine, Tongji University, Shanghai, China
- Department of Biochemistry and Molecular Biology, Tongji University School of Medicine, Shanghai, China
| | - Yingao Li
- Department of Ophthalmology of Shanghai Tongji Hospital, Laboratory of Clinical Visual Science of Tongji Eye Institute, School of Medicine, Tongji University, Shanghai, China
- Department of Biochemistry and Molecular Biology, Tongji University School of Medicine, Shanghai, China
| | - Lilin Zhu
- Department of Ophthalmology of Shanghai Tongji Hospital, Laboratory of Clinical Visual Science of Tongji Eye Institute, School of Medicine, Tongji University, Shanghai, China
- Department of Biochemistry and Molecular Biology, Tongji University School of Medicine, Shanghai, China
| | - Jinyuan Xu
- Department of Ophthalmology of Shanghai Tongji Hospital, Laboratory of Clinical Visual Science of Tongji Eye Institute, School of Medicine, Tongji University, Shanghai, China
- Department of Biochemistry and Molecular Biology, Tongji University School of Medicine, Shanghai, China
| | - Zijun Feng
- Department of Biochemistry and Molecular Biology, Tongji University School of Medicine, Shanghai, China
| | - Hao Chen
- Department of Ophthalmology of Shanghai Tenth People's Hospital, Tongji University, Shanghai, China
| | - Si Shi
- Department of Ophthalmology of Shanghai Tongji Hospital, Laboratory of Clinical Visual Science of Tongji Eye Institute, School of Medicine, Tongji University, Shanghai, China
- Department of Biochemistry and Molecular Biology, Tongji University School of Medicine, Shanghai, China
| | - Caiying Liu
- Department of Ophthalmology of Shanghai Tongji Hospital, Laboratory of Clinical Visual Science of Tongji Eye Institute, School of Medicine, Tongji University, Shanghai, China
- Department of Biochemistry and Molecular Biology, Tongji University School of Medicine, Shanghai, China
| | - Qingjian Ou
- Department of Ophthalmology of Shanghai Tongji Hospital, Laboratory of Clinical Visual Science of Tongji Eye Institute, School of Medicine, Tongji University, Shanghai, China
- Department of Pharmacology, Tongji University School of Medicine, Shanghai, China
| | - Furong Gao
- Department of Ophthalmology of Shanghai Tongji Hospital, Laboratory of Clinical Visual Science of Tongji Eye Institute, School of Medicine, Tongji University, Shanghai, China
- Department of Biochemistry and Molecular Biology, Tongji University School of Medicine, Shanghai, China
| | - Jieping Zhang
- Department of Ophthalmology of Shanghai Tongji Hospital, Laboratory of Clinical Visual Science of Tongji Eye Institute, School of Medicine, Tongji University, Shanghai, China
- Department of Pharmacology, Tongji University School of Medicine, Shanghai, China
| | - Caixia Jin
- Department of Ophthalmology of Shanghai Tongji Hospital, Laboratory of Clinical Visual Science of Tongji Eye Institute, School of Medicine, Tongji University, Shanghai, China
- Department of Biochemistry and Molecular Biology, Tongji University School of Medicine, Shanghai, China
| | - Jingying Xu
- Department of Ophthalmology of Shanghai Tongji Hospital, Laboratory of Clinical Visual Science of Tongji Eye Institute, School of Medicine, Tongji University, Shanghai, China
- Department of Biochemistry and Molecular Biology, Tongji University School of Medicine, Shanghai, China
| | - Jiao Li
- Department of Biochemistry and Molecular Biology, Tongji University School of Medicine, Shanghai, China
| | - Jingfa Zhang
- Department of Ophthalmology of Shanghai First People's Hospital, Shanghai Jiaotong University, Shanghai, China
| | - Yanlong Bi
- Department of Ophthalmology of Shanghai Tongji Hospital, Laboratory of Clinical Visual Science of Tongji Eye Institute, School of Medicine, Tongji University, Shanghai, China
| | - Guo-Tong Xu
- Department of Ophthalmology of Shanghai Tongji Hospital, Laboratory of Clinical Visual Science of Tongji Eye Institute, School of Medicine, Tongji University, Shanghai, China
- Department of Pharmacology, Tongji University School of Medicine, Shanghai, China
| | - Juan Wang
- Department of Ophthalmology of Shanghai Tongji Hospital, Laboratory of Clinical Visual Science of Tongji Eye Institute, School of Medicine, Tongji University, Shanghai, China
- Department of Human Genetics, Tongji University School of Medicine, Shanghai, China
| | - Haibin Tian
- Department of Ophthalmology of Shanghai Tongji Hospital, Laboratory of Clinical Visual Science of Tongji Eye Institute, School of Medicine, Tongji University, Shanghai, China
- Department of Biochemistry and Molecular Biology, Tongji University School of Medicine, Shanghai, China
| | - Lixia Lu
- Department of Ophthalmology of Shanghai Tongji Hospital, Laboratory of Clinical Visual Science of Tongji Eye Institute, School of Medicine, Tongji University, Shanghai, China
- Department of Biochemistry and Molecular Biology, Tongji University School of Medicine, Shanghai, China
| |
Collapse
|
14
|
Kelly LE, El-Hodiri HM, Crider A, Fischer AJ. Protein phosphatases regulate the formation of Müller glia-derived progenitor cells in the chick retina. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.12.11.570629. [PMID: 38168320 PMCID: PMC10760049 DOI: 10.1101/2023.12.11.570629] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/05/2024]
Abstract
Different kinase-dependent cell signaling pathways are known to play important roles in glia-mediated neuroprotection and reprogramming of Müller glia (MG) into Müller glia-derived progenitor cells (MGPCs) in the retina. However, very little is known about the phosphatases that regulate kinase-dependent signaling in MG. Using single-cell RNA-sequencing (scRNA-seq) databases, we investigated patterns of expression of Dual Specificity Phosphatases (DUSP1/6) and other protein phosphatases in normal and damaged chick retinas. We found that DUSP1, DUSP6, PPP3CB, PPP3R1 and PPPM1A/B/D/E/G are dynamically expressed by MG and MGPCs in retinas during the process of reprogramming. We find that inhibition of DUSP1/6 and PP2C phosphatases enhances the formation of proliferating MGPCs in damaged retinas and in retinas treated with insulin in FGF2 in the absence of damage. By contrast, inhibition of PP2B phosphatases suppressed the formation of proliferating MGPCs, but increased numbers of proliferating MGPCs in undamaged retinas treated with insulin and FGF2. In damaged retinas, inhibition of DUSP1/6 increased levels of pERK1/2 and cFos in MG whereas inhibition of PP2B's decreased levels of pStat3 and pS6 in MG. Analyses of scRNA-seq libraries identified numerous differentially activated gene modules in MG in damaged retinas versus MG in retinas treated with insulin+FGF2 suggesting significant differences in kinase-dependent signaling pathways that converge on the formation of MGPCs. Inhibition of phosphatases had no significant effects upon numbers of dying cells in damaged retinas. We conclude that the activity of different protein phosphatases "fine-tune" the cell signaling responses of MG in damaged retinas and during the reprogramming of MG into MGPCs.
Collapse
Affiliation(s)
- Lisa E. Kelly
- Department of Neuroscience, College of Medicine, The Ohio State University, Columbus, OH
| | - Heithem M. El-Hodiri
- Department of Neuroscience, College of Medicine, The Ohio State University, Columbus, OH
| | - Andrew Crider
- Department of Neuroscience, College of Medicine, The Ohio State University, Columbus, OH
| | - Andy J. Fischer
- Department of Neuroscience, College of Medicine, The Ohio State University, Columbus, OH
| |
Collapse
|
15
|
El-Hodiri HM, Bentley JR, Reske AG, Taylor OB, Palazzo I, Campbell WA, Halloy NR, Fischer AJ. Heparin-binding epidermal growth factor and fibroblast growth factor 2 rescue Müller glia-derived progenitor cell formation in microglia- and macrophage-ablated chick retinas. Development 2023; 150:dev202070. [PMID: 37971210 PMCID: PMC10730090 DOI: 10.1242/dev.202070] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2023] [Accepted: 11/02/2023] [Indexed: 11/19/2023]
Abstract
Recent studies have demonstrated the impact of pro-inflammatory signaling and reactive microglia/macrophages on the formation of Müller glial-derived progenitor cells (MGPCs) in the retina. In chick retina, ablation of microglia/macrophages prevents the formation of MGPCs. Analyses of single-cell RNA-sequencing chick retinal libraries revealed that quiescent and activated microglia/macrophages have a significant impact upon the transcriptomic profile of Müller glia (MG). In damaged monocyte-depleted retinas, MG fail to upregulate genes related to different cell signaling pathways, including those related to Wnt, heparin-binding epidermal growth factor (HBEGF), fibroblast growth factor (FGF) and retinoic acid receptors. Inhibition of GSK3β, to simulate Wnt signaling, failed to rescue the deficit in MGPC formation, whereas application of HBEGF or FGF2 completely rescued the formation of MGPCs in monocyte-depleted retinas. Inhibition of Smad3 or activation of retinoic acid receptors partially rescued the formation of MGPCs in monocyte-depleted retinas. We conclude that signals produced by reactive microglia/macrophages in damaged retinas stimulate MG to upregulate cell signaling through HBEGF, FGF and retinoic acid, and downregulate signaling through TGFβ/Smad3 to promote the reprogramming of MG into proliferating MGPCs.
Collapse
Affiliation(s)
- Heithem M. El-Hodiri
- Department of Neuroscience, College of Medicine, The Ohio State University, Columbus, OH 43221, USA
| | - James R. Bentley
- Department of Neuroscience, College of Medicine, The Ohio State University, Columbus, OH 43221, USA
| | - Alana G. Reske
- Department of Neuroscience, College of Medicine, The Ohio State University, Columbus, OH 43221, USA
| | - Olivia B. Taylor
- Department of Neuroscience, College of Medicine, The Ohio State University, Columbus, OH 43221, USA
| | - Isabella Palazzo
- Solomon Snyder Department of Neuroscience, Johns Hopkins University, Baltimore, MD 21205, USA
| | - Warren A. Campbell
- Department of Neuroscience, College of Medicine, The Ohio State University, Columbus, OH 43221, USA
| | - Nicklaus R. Halloy
- Department of Neuroscience, College of Medicine, The Ohio State University, Columbus, OH 43221, USA
| | - Andy J. Fischer
- Department of Neuroscience, College of Medicine, The Ohio State University, Columbus, OH 43221, USA
| |
Collapse
|
16
|
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
|
17
|
Campbell WA, El-Hodiri HM, Torres D, Hawthorn EC, Kelly LE, Volkov L, Akanonu D, Fischer AJ. Chromatin access regulates the formation of Müller glia-derived progenitor cells in the retina. Glia 2023; 71:1729-1754. [PMID: 36971459 PMCID: PMC11335016 DOI: 10.1002/glia.24366] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2022] [Revised: 03/06/2023] [Accepted: 03/12/2023] [Indexed: 03/29/2023]
Abstract
Chromatin access and epigenetic control over gene expression play important roles in regulating developmental processes. However, little is known about how chromatin access and epigenetic gene silencing influence mature glial cells and retinal regeneration. Herein, we investigate the expression and functions of S-adenosylhomocysteine hydrolase (SAHH; AHCY) and histone methyltransferases (HMTs) during the formation of Müller glia (MG)-derived progenitor cells (MGPCs) in the chick and mouse retinas. In chick, AHCY, AHCYL1 and AHCYL2, and many different HMTs are dynamically expressed by MG and MGPCs in damaged retinas. Inhibition of SAHH reduced levels of H3K27me3 and potently blocks the formation of proliferating MGPCs. By using a combination of single cell RNA-seq and single cell ATAC-seq, we find significant changes in gene expression and chromatin access in MG with SAHH inhibition and NMDA-treatment; many of these genes are associated with glial and neuronal differentiation. A strong correlation across gene expression, chromatin access, and transcription factor motif access in MG was observed for transcription factors known to convey glial identity and promote retinal development. By comparison, in the mouse retina, inhibition of SAHH has no influence on the differentiation of neuron-like cells from Ascl1-overexpressing MG. We conclude that in the chick the activity of SAHH and HMTs are required for the reprogramming of MG into MGPCs by regulating chromatin access to transcription factors associated with glial differentiation and retinal development.
Collapse
Affiliation(s)
- Warren A. Campbell
- Department of Neuroscience, College of Medicine, The Ohio State University, Columbus, OH
| | - Heithem M. El-Hodiri
- Department of Neuroscience, College of Medicine, The Ohio State University, Columbus, OH
| | - Diego Torres
- Department of Neuroscience, College of Medicine, The Ohio State University, Columbus, OH
| | - Evan C. Hawthorn
- Department of Neuroscience, College of Medicine, The Ohio State University, Columbus, OH
| | - Lisa E. Kelly
- Department of Neuroscience, College of Medicine, The Ohio State University, Columbus, OH
| | - Leo Volkov
- Department of Pathology and Immunology, Washington University School of Medicine, St. Louis, MO
| | - David Akanonu
- Neuroscience Graduate Program, University of Michigan, Ann Arbor, MI
| | - Andy J. Fischer
- Department of Neuroscience, College of Medicine, The Ohio State University, Columbus, OH
| |
Collapse
|
18
|
El-Hodiri HM, Bentley J, Reske A, Palazzo I, Campbell WA, Halloy NR, Fischer AJ. Formation of Müller glia-derived progenitor cells in retinas depleted of microglia. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.06.08.544205. [PMID: 37333380 PMCID: PMC10274900 DOI: 10.1101/2023.06.08.544205] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/20/2023]
Abstract
Recent studies have demonstrated the complex coordination of pro-inflammatory signaling and reactive microglia/macrophage on the formation Müller glial-derived progenitor cells (MGPCs) in the retinas of fish, birds and mice. We generated scRNA-seq libraries to identify transcriptional changes in Müller glia (MG) that result from the depletion of microglia from the chick retina. We found significant changes in different networks of genes in MG in normal and damaged retinas when the microglia are ablated. We identified a failure of MG to upregulate Wnt-ligands, Heparin binding epidermal growth factor (HBEGF), Fibroblast growth factor (FGF), retinoic acid receptors and genes related to Notch-signaling. Inhibition of GSK3β, to simulate Wnt-signaling, failed to rescue the deficit in formation of proliferating MGPCs in damaged retinas missing microglia. By comparison, application of HBEGF or FGF2 completely rescued the formation of proliferating MGPCs in microglia-depleted retinas. Similarly, injection of a small molecule inhibitor to Smad3 or agonist to retinoic acid receptors partially rescued the formation of proliferating MGPCs in microglia-depleted damaged retinas. According to scRNA-seq libraries, patterns of expression of ligands, receptors, signal transducers and/or processing enzymes to cell-signaling via HBEGF, FGF, retinoic acid and TGFβ are rapidly and transiently upregulated by MG after neuronal damage, consistent with important roles for these cell-signaling pathways in regulating the formation of MGPCs. We conclude that quiescent and activated microglia have a significant impact upon the transcriptomic profile of MG. We conclude that signals produced by reactive microglia in damaged retinas stimulate MG to upregulate cell signaling through HBEGF, FGF and retinoic acid, and downregulate signaling through TGFβ/Smad3 to promote the reprogramming on MG into proliferating MGPCs.
Collapse
Affiliation(s)
- Heithem M. El-Hodiri
- Department of Neuroscience, College of Medicine, The Ohio State University, Columbus, OH
| | - James Bentley
- Department of Neuroscience, College of Medicine, The Ohio State University, Columbus, OH
| | - Alana Reske
- Department of Neuroscience, College of Medicine, The Ohio State University, Columbus, OH
| | - Isabella Palazzo
- Solomon Snyder Department of Neuroscience, Johns Hopkins University, Baltimore, MD
| | - Warren A. Campbell
- Department of Neuroscience, College of Medicine, The Ohio State University, Columbus, OH
| | - Nicklaus R. Halloy
- Department of Neuroscience, College of Medicine, The Ohio State University, Columbus, OH
| | - Andy J. Fischer
- Department of Neuroscience, College of Medicine, The Ohio State University, Columbus, OH
| |
Collapse
|
19
|
Palazzo I, Kelly L, Koenig L, Fischer AJ. Patterns of NFkB activation resulting from damage, reactive microglia, cytokines, and growth factors in the mouse retina. Exp Neurol 2023; 359:114233. [PMID: 36174748 PMCID: PMC9722628 DOI: 10.1016/j.expneurol.2022.114233] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2022] [Revised: 09/06/2022] [Accepted: 09/22/2022] [Indexed: 12/30/2022]
Abstract
Müller glia are a cellular source for neuronal regeneration in vertebrate retinas. However, the capacity for retinal regeneration varies widely across species. Understanding the mechanisms that regulate the reprogramming of Müller glia into progenitor cells is key to reversing the loss of vision that occurs with retinal diseases. In the mammalian retina, NFkB signaling promotes glial reactivity and represses the reprogramming of Müller glia into progenitor cells. Here we investigate different cytokines, growth factors, cell signaling pathways, and damage paradigms that influence NFkB-signaling in the mouse retina. We find that exogenous TNF and IL1β potently activate NFkB-signaling in Müller glia in undamaged retinas, and this activation is independent of microglia. By comparison, TLR1/2 agonist indirectly activates NFkB-signaling in Müller glia, and this activation depends on the presence of microglia as Tlr2 is predominantly expressed by microglia, but not other types of retinal cells. Exogenous FGF2 did not activate NFkB-signaling, whereas CNTF, Osteopontin, WNT4, or inhibition of GSK3β activated NFkB in Müller glia in the absence of neuronal damage. By comparison, dexamethasone, a glucocorticoid agonist, suppressed NFkB-signaling in Müller glia in damaged retinas, in addition to reducing numbers of dying cells and the accumulation of reactive microglia. Although NMDA-induced retinal damage activated NFkB in Müller glia, optic nerve crush had no effect on NFkB activation within the retina, whereas glial cells within the optic nerve were responsive. We conclude that the NFkB pathway is activated in retinal Müller glia in response to many different cell signaling pathways, and activation often depends on signals produced by reactive microglia.
Collapse
Affiliation(s)
- Isabella Palazzo
- Solomon H. Snyder Department of Neuroscience, Johns Hopkins University School of Medicine, Baltimore, MD, United States of America
| | - Lisa Kelly
- Department of Neuroscience, College of Medicine, The Ohio State University, Columbus, OH, United States of America
| | - Lindsay Koenig
- Department of Neuroscience, College of Medicine, The Ohio State University, Columbus, OH, United States of America
| | - Andy J Fischer
- Department of Neuroscience, College of Medicine, The Ohio State University, Columbus, OH, United States of America.
| |
Collapse
|
20
|
The transcriptional profile of keloidal Schwann cells. Exp Mol Med 2022; 54:1886-1900. [PMID: 36333467 PMCID: PMC9722693 DOI: 10.1038/s12276-022-00874-1] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2022] [Revised: 07/07/2022] [Accepted: 08/08/2022] [Indexed: 11/06/2022] Open
Abstract
Recently, a specific Schwann cell type with profibrotic and tissue regenerative properties that contributes to keloid formation has been identified. In the present study, we reanalyzed published single-cell RNA sequencing (scRNA-seq) studies of keloids, healthy skin, and normal scars to reliably determine the specific gene expression profile of keloid-specific Schwann cell types in more detail. We were able to confirm the presence of the repair-like, profibrotic Schwann cell type in the datasets of all three studies and identified a specific gene-set for these Schwann cells. In contrast to keloids, in normal scars, the number of Schwann cells was not increased, nor was their gene expression profile distinctly different from that of Schwann cells of normal skin. In addition, our bioinformatics analysis provided evidence for a role of transcription factors of the AP1, STAT, and KLF families, and members of the IER genes in the dedifferentiation process of keloidal Schwann cells. Together, our analysis strengthens the role of the profibrotic Schwann cell type in the formation of keloids. Knowledge of the exact gene expression profile of these Schwann cells will facilitate their identification in other organs and diseases.
Collapse
|
21
|
Chen Y, Xia Q, Zeng Y, Zhang Y, Zhang M. Regulations of Retinal Inflammation: Focusing on Müller Glia. Front Cell Dev Biol 2022; 10:898652. [PMID: 35573676 PMCID: PMC9091449 DOI: 10.3389/fcell.2022.898652] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2022] [Accepted: 04/11/2022] [Indexed: 12/12/2022] Open
Abstract
Retinal inflammation underlies multiple prevalent retinal diseases. While microglia are one of the most studied cell types regarding retinal inflammation, growing evidence shows that Müller glia play critical roles in the regulation of retinal inflammation. Müller glia express various receptors for cytokines and release cytokines to regulate inflammation. Müller glia are part of the blood-retinal barrier and interact with microglia in the inflammatory responses. The unique metabolic features of Müller glia in the retina makes them vital for retinal homeostasis maintenance, regulating retinal inflammation by lipid metabolism, purine metabolism, iron metabolism, trophic factors, and antioxidants. miRNAs in Müller glia regulate inflammatory responses via different mechanisms and potentially regulate retinal regeneration. Novel therapies are explored targeting Müller glia for inflammatory retinal diseases treatment. Here we review new findings regarding the roles of Müller glia in retinal inflammation and discuss the related novel therapies for retinal diseases.
Collapse
Affiliation(s)
- Yingying Chen
- Department of Ophthalmology, Sichuan University West China Hospital, Sichuan University, Chengdu, China
- Research Laboratory of Macular Disease, West China Hospital, Sichuan University, Chengdu, China
| | - Qinghong Xia
- Operating Room of Anesthesia Surgery Center, West China Hospital, Sichuan University, Chengdu, China
- West China School of Nursing, Sichuan University, Chengdu, China
| | - Yue Zeng
- Department of Ophthalmology, Sichuan University West China Hospital, Sichuan University, Chengdu, China
- Research Laboratory of Macular Disease, West China Hospital, Sichuan University, Chengdu, China
| | - Yun Zhang
- Department of Ophthalmology, Sichuan University West China Hospital, Sichuan University, Chengdu, China
- Research Laboratory of Macular Disease, West China Hospital, Sichuan University, Chengdu, China
| | - Meixia Zhang
- Department of Ophthalmology, Sichuan University West China Hospital, Sichuan University, Chengdu, China
- Research Laboratory of Macular Disease, West China Hospital, Sichuan University, Chengdu, China
- *Correspondence: Meixia Zhang,
| |
Collapse
|
22
|
Campbell WA, Tangeman A, El-Hodiri HM, Hawthorn EC, Hathoot M, Blum S, Hoang T, Blackshaw S, Fischer AJ. Fatty acid-binding proteins and fatty acid synthase influence glial reactivity and promote the formation of Müller glia-derived progenitor cells in the chick retina. Development 2022; 149:274285. [PMID: 35132991 PMCID: PMC8959147 DOI: 10.1242/dev.200127] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2021] [Accepted: 01/18/2022] [Indexed: 11/20/2022]
Abstract
A recent comparative transcriptomic study of Müller glia (MG) in vertebrate retinas revealed that fatty acid binding proteins (FABPs) are among the most highly expressed genes in chick ( Hoang et al., 2020). Here, we investigate how FABPs and fatty acid synthase (FASN) influence glial cells in the chick retina. During development, FABP7 is highly expressed by retinal progenitor cells and maturing MG, whereas FABP5 is upregulated in maturing MG. PMP2 (FABP8) is expressed by oligodendrocytes and FABP5 is expressed by non-astrocytic inner retinal glial cells, and both of these FABPs are upregulated by activated MG. In addition to suppressing the formation of Müller glia-derived progenitor cells (MGPCs), we find that FABP-inhibition suppresses the proliferation of microglia. FABP-inhibition induces distinct changes in single cell transcriptomic profiles, indicating transitions of MG from resting to reactive states and suppressed MGPC formation, with upregulation of gene modules for gliogenesis and decreases in neurogenesis. FASN-inhibition increases the proliferation of microglia and suppresses the formation of MGPCs. We conclude that fatty acid metabolism and cell signaling involving fatty acids are important in regulating the reactivity and dedifferentiation of MG, and the proliferation of microglia and MGPCs.
Collapse
Affiliation(s)
- Warren A Campbell
- Department of Neuroscience, College of Medicine, The Ohio State University, Columbus, OH 43210, USA
| | - Allen Tangeman
- Department of Neuroscience, College of Medicine, The Ohio State University, Columbus, OH 43210, USA
| | - Heithem M El-Hodiri
- Department of Neuroscience, College of Medicine, The Ohio State University, Columbus, OH 43210, USA
| | - Evan C Hawthorn
- Department of Neuroscience, College of Medicine, The Ohio State University, Columbus, OH 43210, USA
| | - Maddie Hathoot
- Department of Neuroscience, College of Medicine, The Ohio State University, Columbus, OH 43210, USA
| | - Sydney Blum
- Department of Neuroscience, College of Medicine, The Ohio State University, Columbus, OH 43210, USA
| | - Thanh Hoang
- Solomon H. Snyder Department of Neuroscience, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
| | - Seth Blackshaw
- Solomon H. Snyder Department of Neuroscience, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
| | - Andy J Fischer
- Department of Neuroscience, College of Medicine, The Ohio State University, Columbus, OH 43210, USA
| |
Collapse
|
23
|
El-Hodiri HM, Campbell WA, Kelly LE, Hawthorn EC, Schwartz M, Jalligampala A, McCall MA, Meyer K, Fischer AJ. Nuclear Factor I in neurons, glia and during the formation of Müller glia-derived progenitor cells in avian, porcine and primate retinas. J Comp Neurol 2021; 530:1213-1230. [PMID: 34729776 DOI: 10.1002/cne.25270] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2021] [Accepted: 10/21/2021] [Indexed: 11/10/2022]
Abstract
The regenerative potential of Müller glia (MG) is extraordinary in fish, poor in chick and terrible in mammals. In the chick model, MG readily reprogram into proliferating Müller glia-derived progenitor cells (MGPCs), but neuronal differentiation is very limited. The factors that suppress the neurogenic potential of MGPCs in the chick are slowly being revealed. Isoforms of Nuclear Factor I (NFI) are cell-intrinsic factors that limit neurogenic potential; these factors are required for the formation of MG in the developing mouse retina (Clark et al., 2019) and deletion of these factors reprograms MG into neuron-like cells in mature mouse retina (Hoang et al., 2020). Accordingly, we sought to characterize the patterns of expression NFIs in the developing, mature and damaged chick retina. In addition, we characterized patterns of expression of NFIs in the retinas of large mammals, pigs and monkeys. Using a combination of single cell RNA-sequencing (scRNA-seq) and immunolabeling we probed for patterns of expression. In embryonic chick, levels of NFIs are very low in early E5 (embryonic day 5) retinal progenitor cells (RPCs), up-regulated in E8 RPCs, further up-regulated in differentiating MG at E12 and E15. NFIs are maintained in mature resting MG, microglia and neurons. Levels of NFIs are reduced in activated MG in retinas treated with NMDA and/or insulin+FGF2, and further down-regulated in proliferating MGPCs. However, levels of NFIs in MGPCs were significantly higher than those seen in RPCs. Immunolabeling for NFIA and NFIB closely matched patterns of expression revealed in different types of retinal neurons and glia, consistent with findings from scRNA-seq. In addition, we find expression of NFIA and NFIB through progenitors in the circumferential marginal zone at the far periphery of the retina. We find similar patterns of expression for NFIs in scRNA-seq databases for pig and monkey retinas. Patterns of expression of NFIA and NFIB were validated with immunofluorescence in pig and monkey retinas wherein these factors were predominantly detected in MG and a few types of inner retinal neurons. In summary, NFIA and NFIB are prominently expressed in developing chick retina and by mature neurons and glia in the retinas of chicks, pigs and monkeys. Although levels of NFIs are decreased in chick, in MGPCs these levels remain higher than those seen in neurogenic RPCs. We propose that the neurogenic potential of MGPCs in the chick retina is suppressed by NFIs. This article is protected by copyright. All rights reserved.
Collapse
Affiliation(s)
- Heithem M El-Hodiri
- Department of Neuroscience, College of Medicine, The Ohio State University, Columbus, OH.,Department of Anatomical Sciences and Neurobiology, University of Louisville, Louisville, KY
| | - Warren A Campbell
- Department of Neuroscience, College of Medicine, The Ohio State University, Columbus, OH
| | - Lisa E Kelly
- Department of Neuroscience, College of Medicine, The Ohio State University, Columbus, OH
| | - Evan C Hawthorn
- Department of Neuroscience, College of Medicine, The Ohio State University, Columbus, OH
| | - Maura Schwartz
- Center for Gene Therapy, Nationwide Children's Hospital, Columbus, OH
| | - Archana Jalligampala
- Department of Ophthalmology and Visual Sciences, University of Louisville, Louisville, KY
| | - Maureen A McCall
- Department of Ophthalmology and Visual Sciences, University of Louisville, Louisville, KY
| | - Kathrin Meyer
- Center for Gene Therapy, Nationwide Children's Hospital, Columbus, OH
| | - Andy J Fischer
- Department of Neuroscience, College of Medicine, The Ohio State University, Columbus, OH
| |
Collapse
|
24
|
Gautam P, Hamashima K, Chen Y, Zeng Y, Makovoz B, Parikh BH, Lee HY, Lau KA, Su X, Wong RCB, Chan WK, Li H, Blenkinsop TA, Loh YH. Multi-species single-cell transcriptomic analysis of ocular compartment regulons. Nat Commun 2021; 12:5675. [PMID: 34584087 PMCID: PMC8478974 DOI: 10.1038/s41467-021-25968-8] [Citation(s) in RCA: 43] [Impact Index Per Article: 14.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2020] [Accepted: 09/07/2021] [Indexed: 11/23/2022] Open
Abstract
The retina is a widely profiled tissue in multiple species by single-cell RNA sequencing studies. However, integrative research of the retina across species is lacking. Here, we construct the first single-cell atlas of the human and porcine ocular compartments and study inter-species differences in the retina. In addition to that, we identify putative adult stem cells present in the iris tissue. We also create a disease map of genes involved in eye disorders across compartments of the eye. Furthermore, we probe the regulons of different cell populations, which include transcription factors and receptor-ligand interactions and reveal unique directional signalling between ocular cell types. In addition, we study conservation of regulons across vertebrates and zebrafish to identify common core factors. Here, we show perturbation of KLF7 gene expression during retinal ganglion cells differentiation and conclude that it plays a significant role in the maturation of retinal ganglion cells. A comprehensive analysis of the ocular networks among various tissues is necessary to understand eye physiology in health and disease. Here the authors present a multi-species single-cell transcriptomic atlas consisting of cells of the cornea, iris, ciliary body, neural retina, retinal pigmented epithelium, and choroid.
Collapse
Affiliation(s)
- Pradeep Gautam
- Cell Fate Engineering and Therapeutics Laboratory, A*STAR Institute of Molecular and Cell Biology, Singapore, 138673, Singapore.,Department of Biological Sciences, National University of Singapore, Singapore, 117543, Singapore
| | - Kiyofumi Hamashima
- Cell Fate Engineering and Therapeutics Laboratory, A*STAR Institute of Molecular and Cell Biology, Singapore, 138673, Singapore
| | - Ying Chen
- Cell Fate Engineering and Therapeutics Laboratory, A*STAR Institute of Molecular and Cell Biology, Singapore, 138673, Singapore.,Department of Biological Sciences, National University of Singapore, Singapore, 117543, Singapore.,Integrative Sciences and Engineering Programme (ISEP), NUS Graduate School, National University of Singapore, 21 Lower Kent Ridge Road, Singapore, 119077, Singapore
| | - Yingying Zeng
- Cell Fate Engineering and Therapeutics Laboratory, A*STAR Institute of Molecular and Cell Biology, Singapore, 138673, Singapore.,School of Biological Sciences, Nanyang Technological University, Singapore, 637551, Singapore
| | - Bar Makovoz
- Icahn School of Medicine at Mount Sinai, New York, NY, 10029, USA
| | - Bhav Harshad Parikh
- Department of Ophthalmology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, Singapore.,Translational Retinal Research Laboratory, A*STAR Institute of Molecular and Cell Biology, Singapore, 138673, Singapore
| | - Hsin Yee Lee
- Cell Fate Engineering and Therapeutics Laboratory, A*STAR Institute of Molecular and Cell Biology, Singapore, 138673, Singapore
| | - Katherine Anne Lau
- Cell Fate Engineering and Therapeutics Laboratory, A*STAR Institute of Molecular and Cell Biology, Singapore, 138673, Singapore
| | - Xinyi Su
- Department of Ophthalmology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, Singapore.,Translational Retinal Research Laboratory, A*STAR Institute of Molecular and Cell Biology, Singapore, 138673, Singapore.,Singapore Eye Research Institute, 11 Third Hospital Avenue, Singapore, 168751, Singapore
| | - Raymond C B Wong
- Centre for Eye Research Australia, Melbourne, Vic, Australia.,Ophthalmology, Department of Surgery, University of Melbourne, Melbourne, Vic, Australia.,Shenzhen Eye Hospital, Shenzhen University School of Medicine, Shenzhen, China
| | - Woon-Khiong Chan
- Department of Biological Sciences, National University of Singapore, Singapore, 117543, Singapore.,Integrative Sciences and Engineering Programme (ISEP), NUS Graduate School, National University of Singapore, 21 Lower Kent Ridge Road, Singapore, 119077, Singapore
| | - Hu Li
- Center for Individualized Medicine, Department of Molecular Pharmacology & Experimental Therapeutics, Mayo Clinic, Rochester, MN, 55905, USA.
| | | | - Yuin-Han Loh
- Cell Fate Engineering and Therapeutics Laboratory, A*STAR Institute of Molecular and Cell Biology, Singapore, 138673, Singapore. .,Department of Biological Sciences, National University of Singapore, Singapore, 117543, Singapore. .,Integrative Sciences and Engineering Programme (ISEP), NUS Graduate School, National University of Singapore, 21 Lower Kent Ridge Road, Singapore, 119077, Singapore. .,Department of Physiology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, 117593, Singapore.
| |
Collapse
|
25
|
Multimodal imaging and functional analysis of the chick NMDA retinal damage model. PLoS One 2021; 16:e0257148. [PMID: 34492087 PMCID: PMC8423281 DOI: 10.1371/journal.pone.0257148] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2021] [Accepted: 08/24/2021] [Indexed: 11/19/2022] Open
Abstract
Objectives The chick is rapidly becoming a standardized preclinical model in vision research to study mechanisms of ocular disease. We seek to comprehensively evaluate the N-methyl-D-aspartate (NMDA) model of excitotoxic retinal damage using multimodal imaging, functional, and histologic approaches in NMDA-damaged, vehicle-treated, and undamaged chicks. Methods Chicks were either left undamaged in both eyes or were injected with NMDA in the left eye and saline (vehicle) in the right eye. TUNEL assay was performed on chicks to assess levels of retinal cell death one day post-injection of NMDA or saline and on age-matched untreated chicks. Spectral domain optical coherence tomography (SD-OCT) was performed weekly on chicks and age-matched controls day 1 (D1) up to D28 post-injection. Light adapted electroretinograms (ERG) were performed alongside SD-OCT measurements on post-injection chicks along with age-matched untreated controls. Results Untreated and vehicle-treated eyes had no TUNEL positive cells while NMDA-treated eyes accumulated large numbers of TUNEL positive cells in the Inner Nuclear Layer (INL), but not other layers, at D1 post injection. Significant inner retina swelling or edema was found on SD-OCT imaging at D1 post-injection which resolved at subsequent timepoints. Both the INL and the inner plexiform layer significantly thinned by one-week post-injection and did not recover for the duration of the measurements. On ERG, NMDA-treated eyes had significantly reduced amplitudes of all parameters at D1 with all metrics improving over time. The b-wave, oscillatory potentials, and ON/OFF bipolar responses were the most affected with at least 70% reduction immediately after damage compared to the fellow eye control. Conclusion This study establishes a normative baseline on the retinal health and gross functional ability as well as intraocular pressures of undamaged, vehicle-treated, and NMDA-damaged chicks to provide a standard for comparing therapeutic treatment studies in this important animal model.
Collapse
|
26
|
Campbell WA, Blum S, Reske A, Hoang T, Blackshaw S, Fischer AJ. Cannabinoid signaling promotes the de-differentiation and proliferation of Müller glia-derived progenitor cells. Glia 2021; 69:2503-2521. [PMID: 34231253 DOI: 10.1002/glia.24056] [Citation(s) in RCA: 21] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2021] [Revised: 06/24/2021] [Accepted: 06/25/2021] [Indexed: 12/11/2022]
Abstract
Endocannabinoids (eCB) are lipid-based neurotransmitters that are known to influence synaptic function in the visual system. eCBs are also known to suppress neuroinflammation in different pathological states. However, nothing is known about the roles of the eCB system during the transition of Müller glia (MG) into proliferating progenitor-like cells in the retina. Accordingly, we used the chick and mouse model to characterize expression patterns of eCB-related genes and applied pharmacological agents to investigate how the eCB system impacts glial reactivity and the capacity of MG to become Müller glia-derived progenitor cells (MGPCs). We queried single cell RNA-seq libraries to identify eCB-related genes and identify cells with dynamic patterns of expression in damaged retinas. MG and inner retinal neurons expressed the eCB receptor CNR1, as well as enzymes involved in eCB metabolism. In the chick, intraocular injections of cannabinoids, 2-Arachidonoylglycerol (2-AG) and Anandamide (AEA), stimulated the formation of MGPCs. Cannabinoid Receptor 1 (CNR1)-agonists and Monoglyceride Lipase-inhibitor promoted the formation of MGPCs, whereas CNR1-antagonist and inhibitors of eCB synthesis suppressed this process. In damaged mouse retinas where MG activate NFkB-signaling, activation of CNR1 decreased and inhibition of CNR1 increased NFkB, whereas levels of neuronal cell death were unaffected. Surprisingly, retinal microglia were largely unaffected by increases or decreases in eCB-signaling in both chick and mouse retinas. We conclude that the eCB system in the retina influences the reactivity of MG and the formation of proliferating MGPCs, but does not influence the reactivity of immune cells in the retina.
Collapse
Affiliation(s)
- Warren A Campbell
- Department of Neuroscience, College of Medicine, The Ohio State University, Columbus, Ohio, USA
| | - Sydney Blum
- Department of Neuroscience, College of Medicine, The Ohio State University, Columbus, Ohio, USA
| | - Alana Reske
- Department of Neuroscience, College of Medicine, The Ohio State University, Columbus, Ohio, USA
| | - Thanh Hoang
- Solomon H. Snyder Department of Neuroscience, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
| | - Seth Blackshaw
- Solomon H. Snyder Department of Neuroscience, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
| | - Andy J Fischer
- Department of Neuroscience, College of Medicine, The Ohio State University, Columbus, Ohio, USA
| |
Collapse
|
27
|
Age-Related Macular Degeneration (AMD) Transmitochondrial Cybrids Protected from Cellular Damage and Death by Human Retinal Progenitor Cells (hRPCs). Stem Cells Int 2021; 2021:6655372. [PMID: 33628267 PMCID: PMC7886532 DOI: 10.1155/2021/6655372] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2020] [Revised: 01/20/2021] [Accepted: 01/25/2021] [Indexed: 02/02/2023] Open
Abstract
Purpose One of the leading causes of irreversible blindness worldwide, age-related macular degeneration (AMD) is a progressive disorder leading to retinal degeneration. While several treatment options exist for the exudative form of AMD, there are currently no FDA-approved treatments for the more common nonexudative (atrophic) form. Mounting evidence suggests that mitochondrial damage and retinal pigment epithelium (RPE) cell death are linked to the pathogenesis of AMD. Human retinal progenitor cells (hRPCs) have been studied as a potential restorative therapy for degenerative conditions of the retina; however, the effects of hRPC treatment on retinal cell survival in AMD have not been elucidated. Methods In this study, we used a cell coculture system consisting of hRPCs and AMD or age-matched normal cybrid cells to characterize the effects of hRPCs in protecting AMD cybrids from cellular and mitochondrial damage and death. Results AMD cybrids cocultured with hRPCs showed (1) increased cell viability; (2) decreased gene expression related to apoptosis, autophagy, endoplasmic reticulum (ER) stress, and antioxidant pathways; and (3) downregulation of mitochondrial replication genes compared to AMD cybrids without hRPC treatment. Furthermore, hRPCs cocultured with AMD cybrids showed upregulation of (1) neuronal and glial markers, as well as (2) putative neuroprotective factors, responses not found when hRPCs were cocultured with age-matched normal cybrids. Conclusion The current study provides the first evidence that therapeutic benefits may be obtainable using a progenitor cell-based approach for atrophic AMD. Our results suggest that bidirectional interactions exist between hRPCs and AMD cybrids such that hRPCs release trophic factors that protect the cybrids against the cellular and mitochondrial changes involved in AMD pathogenesis while, conversely, AMD cybrids upregulate the release of these neuroprotective factors by hRPCs while promoting hRPC differentiation. These in vitro data provide evidence that hRPCs may have therapeutic potential in atrophic AMD.
Collapse
|