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Keuthan CJ, Schaub JA, Wei M, Fang W, Quillen S, Kimball E, Johnson TV, Ji H, Zack DJ, Quigley HA. Regional Gene Expression in the Retina, Optic Nerve Head, and Optic Nerve of Mice with Optic Nerve Crush and Experimental Glaucoma. Int J Mol Sci 2023; 24:13719. [PMID: 37762022 PMCID: PMC10531004 DOI: 10.3390/ijms241813719] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2023] [Revised: 08/28/2023] [Accepted: 08/29/2023] [Indexed: 09/29/2023] Open
Abstract
A major risk factor for glaucomatous optic neuropathy is the level of intraocular pressure (IOP), which can lead to retinal ganglion cell axon injury and cell death. The optic nerve has a rostral unmyelinated portion at the optic nerve head followed by a caudal myelinated region. The unmyelinated region is differentially susceptible to IOP-induced damage in rodent models and human glaucoma. While several studies have analyzed gene expression changes in the mouse optic nerve following optic nerve injury, few were designed to consider the regional gene expression differences that exist between these distinct areas. We performed bulk RNA-sequencing on the retina and separately micro-dissected unmyelinated and myelinated optic nerve regions from naïve C57BL/6 mice, mice after optic nerve crush, and mice with microbead-induced experimental glaucoma (total = 36). Gene expression patterns in the naïve unmyelinated optic nerve showed significant enrichment of the Wnt, Hippo, PI3K-Akt, and transforming growth factor β pathways, as well as extracellular matrix-receptor and cell membrane signaling pathways, compared to the myelinated optic nerve and retina. Gene expression changes induced by both injuries were more extensive in the myelinated optic nerve than the unmyelinated region, and greater after nerve crush than glaucoma. Changes present three and fourteen days after injury largely subsided by six weeks. Gene markers of reactive astrocytes did not consistently differ between injury states. Overall, the transcriptomic phenotype of the mouse unmyelinated optic nerve was significantly different from immediately adjacent tissues, likely dominated by expression in astrocytes, whose junctional complexes are inherently important in responding to IOP elevation.
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Affiliation(s)
- Casey J. Keuthan
- Department of Ophthalmology, Wilmer Eye Institute, School of Medicine, Johns Hopkins University, Baltimore, MD 21287, USA; (C.J.K.)
| | - Julie A. Schaub
- Department of Ophthalmology, Wilmer Eye Institute, School of Medicine, Johns Hopkins University, Baltimore, MD 21287, USA; (C.J.K.)
| | - Meihan Wei
- Department of Biostatistics, Bloomberg School of Public Health, Johns Hopkins University, Baltimore, MD 21205, USA
| | - Weixiang Fang
- Department of Biomedical Engineering, School of Medicine, Johns Hopkins University, Baltimore, MD 21287, USA
| | - Sarah Quillen
- Department of Ophthalmology, Wilmer Eye Institute, School of Medicine, Johns Hopkins University, Baltimore, MD 21287, USA; (C.J.K.)
| | - Elizabeth Kimball
- Department of Ophthalmology, Wilmer Eye Institute, School of Medicine, Johns Hopkins University, Baltimore, MD 21287, USA; (C.J.K.)
| | - Thomas V. Johnson
- Department of Ophthalmology, Wilmer Eye Institute, School of Medicine, Johns Hopkins University, Baltimore, MD 21287, USA; (C.J.K.)
| | - Hongkai Ji
- Department of Biostatistics, Bloomberg School of Public Health, Johns Hopkins University, Baltimore, MD 21205, USA
| | - Donald J. Zack
- Department of Ophthalmology, Wilmer Eye Institute, School of Medicine, Johns Hopkins University, Baltimore, MD 21287, USA; (C.J.K.)
- Departments of Neuroscience, Molecular Biology and Genetics, and Genetic Medicine, School of Medicine, Johns Hopkins University, Baltimore, MD 21287, USA
| | - Harry A. Quigley
- Department of Ophthalmology, Wilmer Eye Institute, School of Medicine, Johns Hopkins University, Baltimore, MD 21287, USA; (C.J.K.)
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Keuthan CJ, Schaub J, Wei M, Fang W, Quillen S, Kimball E, Johnson TV, Ji H, Zack DJ, Quigley HA. Regional Gene Expression in the Retina, Optic Nerve Head, and Optic Nerve of Mice with Experimental Glaucoma and Optic Nerve Crush. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.02.21.529410. [PMID: 36993314 PMCID: PMC10054954 DOI: 10.1101/2023.02.21.529410] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
A major risk factor for glaucomatous optic neuropathy is the level of intraocular pressure (IOP), which can lead to retinal ganglion cell axon injury and cell death. The optic nerve has a rostral unmyelinated portion at the optic nerve head followed by a caudal myelinated region. The unmyelinated region is differentially susceptible to IOP-induced damage in rodent models and in human glaucoma. While several studies have analyzed gene expression changes in the mouse optic nerve following optic nerve injury, few were designed to consider the regional gene expression differences that exist between these distinct areas. We performed bulk RNA-sequencing on the retina and on separately micro-dissected unmyelinated and myelinated optic nerve regions from naïve C57BL/6 mice, mice after optic nerve crush, and mice with microbead-induced experimental glaucoma (total = 36). Gene expression patterns in the naïve unmyelinated optic nerve showed significant enrichment of the Wnt, Hippo, PI3K-Akt, and transforming growth factor β pathways, as well as extracellular matrix-receptor and cell membrane signaling pathways, compared to the myelinated optic nerve and retina. Gene expression changes induced by both injuries were more extensive in the myelinated optic nerve than the unmyelinated region, and greater after nerve crush than glaucoma. Changes three and fourteen days after injury largely subsided by six weeks. Gene markers of reactive astrocytes did not consistently differ between injury states. Overall, the transcriptomic phenotype of the mouse unmyelinated optic nerve was significantly different from immediately adjacent tissues, likely dominated by expression in astrocytes, whose junctional complexes are inherently important in responding to IOP elevation.
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Affiliation(s)
- Casey J. Keuthan
- Department of Ophthalmology, Wilmer Eye Institute, Johns Hopkins University School of Medicine, Baltimore, MD 21231, USA
| | - Julie Schaub
- Department of Ophthalmology, Wilmer Eye Institute, Johns Hopkins University School of Medicine, Baltimore, MD 21231, USA
| | - Meihan Wei
- Department of Biostatistics, Johns Hopkins University Bloomberg School of Public Health, Baltimore, MD 21205, USA
| | - Weixiang Fang
- Department of Biostatistics, Johns Hopkins University Bloomberg School of Public Health, Baltimore, MD 21205, USA
| | - Sarah Quillen
- Department of Ophthalmology, Wilmer Eye Institute, Johns Hopkins University School of Medicine, Baltimore, MD 21231, USA
| | - Elizabeth Kimball
- Department of Ophthalmology, Wilmer Eye Institute, Johns Hopkins University School of Medicine, Baltimore, MD 21231, USA
| | - Thomas V. Johnson
- Department of Ophthalmology, Wilmer Eye Institute, Johns Hopkins University School of Medicine, Baltimore, MD 21231, USA
| | - Hongkai Ji
- Department of Biostatistics, Johns Hopkins University Bloomberg School of Public Health, Baltimore, MD 21205, USA
| | - Donald J. Zack
- Departments of Ophthalmology, Wilmer Eye Institute, Neuroscience, Molecular Biology and Genetics, and Genetic Medicine, Johns Hopkins University School of Medicine, Baltimore, MD 21231, USA
| | - Harry A. Quigley
- Department of Ophthalmology, Wilmer Eye Institute, Johns Hopkins University School of Medicine, Baltimore, MD 21231, USA
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Yu H, Wang X, Kang F, Chen Z, Meng Y, Dai M. Propofol attenuates inflammatory damage on neurons following cerebral infarction by inhibiting excessive activation of microglia. Int J Mol Med 2018; 43:452-460. [PMID: 30431058 DOI: 10.3892/ijmm.2018.3974] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2017] [Accepted: 02/02/2018] [Indexed: 11/06/2022] Open
Affiliation(s)
- Hang Yu
- Intensive Care Unit, The Second Affiliated Hospital, Hainan Medical University, Haikou, Hainan 570311, P.R. China
| | - Xiaozhi Wang
- Intensive Care Unit, The Second Affiliated Hospital, Hainan Medical University, Haikou, Hainan 570311, P.R. China
| | - Fuxin Kang
- Intensive Care Unit, The Second Affiliated Hospital, Hainan Medical University, Haikou, Hainan 570311, P.R. China
| | - Zhile Chen
- Intensive Care Unit, The Second Affiliated Hospital, Hainan Medical University, Haikou, Hainan 570311, P.R. China
| | - Yunxia Meng
- Intensive Care Unit, The Second Affiliated Hospital, Hainan Medical University, Haikou, Hainan 570311, P.R. China
| | - Mingming Dai
- Department of Internal Neurology, The Second Affiliated Hospital, Hainan Medical University, Haikou, Hainan 570311, P.R. China
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Lee JK, Wang B, Reyes M, Armstrong JS, Kulikowicz E, Santos PT, Lee JH, Koehler RC, Martin LJ. Hypothermia and Rewarming Activate a Macroglial Unfolded Protein Response Independent of Hypoxic-Ischemic Brain Injury in Neonatal Piglets. Dev Neurosci 2016; 38:277-294. [PMID: 27622292 DOI: 10.1159/000448585] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2016] [Accepted: 07/20/2016] [Indexed: 12/22/2022] Open
Abstract
Therapeutic hypothermia provides incomplete neuroprotection after hypoxia-ischemia (HI)-induced brain injury in neonates. We previously showed that cortical neuron and white matter apoptosis are promoted by hypothermia and early rewarming in a piglet model of HI. The unfolded protein response (UPR) may be one of the potential mediators of this cell death. Here, neonatal piglets underwent HI or sham surgery followed by 29 h of normothermia, 2 h of normothermia + 27 h of hypothermia or 18 h of hypothermia + rewarming. Piglets recovered for 29 h. Immunohistochemistry for endoplasmic reticulum to nucleus signaling-1 protein (ERN1), a marker of UPR activation, was used to determine the ratios of ERN1+ macroglia and neurons in the motor subcortical white matter and cerebral cortex. The ERN1+ macroglia were immunophenotyped as oligodendrocytes and astrocytes by immunofluorescent colabeling. Temperature (p = 0.046) and HI (p < 0.001) independently affected the ratio of ERN1+ macroglia. In sham piglets, sustained hypothermia (p = 0.011) and rewarming (p = 0.004) increased the ERN1+ macroglia ratio above that in normothermia. HI prior to hypothermia diminished the UPR. Ratios of ERN1+ macroglia correlated with white matter apoptotic profile counts in shams (r = 0.472; p = 0.026), thereby associating UPR activation with white matter apoptosis during hypothermia and rewarming. Accordingly, macroglial cell counts decreased in shams that received sustained hypothermia (p = 0.009) or rewarming (p = 0.007) compared to those in normothermic shams. HI prior to hypothermia neutralized the macroglial cell loss. Neither HI nor temperature affected ERN1+ neuron ratios. In summary, delayed hypothermia and rewarming activate the macroglial UPR, which is associated with white matter apoptosis. HI may decrease the macroglial endoplasmic reticulum stress response after hypothermia and rewarming.
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Affiliation(s)
- Jennifer K Lee
- Department of Anesthesiology and Critical Care Medicine, Johns Hopkins University, Baltimore, Md., USA
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Gonzalez P, Rodríguez FJ. Analysis of the expression of the Wnt family of proteins and its modulatory role on cytokine expression in non activated and activated astroglial cells. Neurosci Res 2016; 114:16-29. [PMID: 27562517 DOI: 10.1016/j.neures.2016.08.003] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2016] [Revised: 08/04/2016] [Accepted: 08/15/2016] [Indexed: 12/23/2022]
Abstract
Despite the essential functions of astrocytes and the emerging relevance of the Wnt family of proteins in the CNS under physiological and pathological conditions, the astroglial expression of this family of proteins and its potential modulatory role on astroglial activation is almost unknown. Thus, we have evaluated the expression of all Wnt ligands, receptors and regulators, and the activation state of Wnt-related signaling pathways in non-activated and differentially activated astroglial cultures. We found that numerous Wnt ligands, receptors and regulators were expressed in non-activated astrocytes, while the Wnt-dependent pathways were constitutively active. Moreover, the expression of most detectable Wnt-related molecules and the activity of the Wnt-dependent pathways suffered post-activation variations which frequently depended on the activation system. Finally, the analysis of the effects exerted by Wnt1 and 5a on the astroglial expression of prototypical genes related to astroglial activation showed that both Wnt ligands increased the astroglial expression of interleukin 1β depending on the experimental context, while did not modulate tumor necrosis factor α, interleukin 6, transforming growth factor β1 and glial fibrillary acidic protein expression. These results strongly suggest that the Wnt family of proteins is involved in how astrocytes modulate and respond to the physiological and pathological CNS.
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Affiliation(s)
- Pau Gonzalez
- Laboratory of Molecular Neurology, National Hospital for Paraplegics, Finca la Peraleda s/n, 45071 Toledo, Spain.
| | - Francisco Javier Rodríguez
- Laboratory of Molecular Neurology, National Hospital for Paraplegics, Finca la Peraleda s/n, 45071 Toledo, Spain.
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