1
|
Yang F, Almasieh M, Levin LA. In Vivo Imaging of Secondary Neurodegeneration Associated With Phosphatidylserine Externalization Along Axotomized Axons. Invest Ophthalmol Vis Sci 2024; 65:24. [PMID: 38345553 PMCID: PMC10866172 DOI: 10.1167/iovs.65.2.24] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2023] [Accepted: 12/11/2023] [Indexed: 02/15/2024] Open
Abstract
Purpose Axonal degeneration in acute and chronic disorders is well-characterized, comprising retrograde (proximal) and Wallerian (distal) degeneration, but the mechanism of propagation remains less understood. Methods Laser injury with a diode-pumped solid-state 532 nm laser was used to axotomize retinal ganglion cell axons. We used confocal in vivo imaging to demonstrate that phosphatidylserine externalization is a biomarker of early axonal degeneration after selective intraretinal axotomy. Results Quantitative dynamic analysis revealed that the rate of axonal degeneration was fastest within 40 minutes, then decreased exponentially afterwards. Axonal degeneration was constrained within the same axotomized axonal bundles. Remarkably, axon degeneration arising from the site of injury induced a secondary degeneration of distal normal axons. Conclusions Axonal degeneration in vivo is a progressive process associated with phosphatidylserine externalization, which can propagate not only along the axon but to adjacent uninjured axons. This finding has implications for acute and chronic neurodegenerative disorders associated with axonal injury.
Collapse
Affiliation(s)
- Fan Yang
- Department of Ophthalmology and Visual Sciences, McGill University, Montreal, Canada
| | - Mohammadali Almasieh
- Department of Ophthalmology and Visual Sciences, McGill University, Montreal, Canada
| | - Leonard A. Levin
- Department of Ophthalmology and Visual Sciences, McGill University, Montreal, Canada
- Department of Neurology and Neurosurgery, McGill University, Montreal, Canada
| |
Collapse
|
2
|
Evans CW, Egid A, Mamsa SSA, Paterson DJ, Ho D, Bartlett CA, Fehily B, Lins BR, Fitzgerald M, Hackett MJ, Smith NM. Elemental Mapping in a Preclinical Animal Model Reveals White Matter Copper Elevation in the Acute Phase of Central Nervous System Trauma. ACS Chem Neurosci 2023; 14:3518-3527. [PMID: 37695072 DOI: 10.1021/acschemneuro.3c00421] [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: 09/12/2023] Open
Abstract
Understanding the chemical events following trauma to the central nervous system could assist in identifying causative mechanisms and potential interventions to protect neural tissue. Here, we apply a partial optic nerve transection model of injury in rats and use synchrotron X-ray fluorescence microscopy (XFM) to perform elemental mapping of metals (K, Ca, Fe, Cu, Zn) and other related elements (P, S, Cl) in white matter tracts. The partial optic nerve injury model and spatial precision of microscopy allow us to obtain previously unattained resolution in mapping elemental changes in response to a primary injury and subsequent secondary effects. We observed significant elevation of Cu levels at multiple time points following the injury, both at the primary injury site and in neural tissue near the injury site vulnerable to secondary damage, as well as significant changes in Cl, K, P, S, and Ca. Our results suggest widespread metal dyshomeostasis in response to central nervous system trauma and that altered Cu homeostasis may be a specific secondary event in response to white matter injury. The findings highlight metal homeostasis as a potential point of intervention in limiting damage following nervous system injury.
Collapse
Affiliation(s)
- Cameron W Evans
- School of Molecular Sciences, The University of Western Australia, Crawley, WA 6009, Australia
| | - Abigail Egid
- School of Molecular Sciences, The University of Western Australia, Crawley, WA 6009, Australia
- University of Bath, Claverton Down, Bath BA2 7AY, United Kingdom
| | - Somayra S A Mamsa
- School of Molecular Sciences, The University of Western Australia, Crawley, WA 6009, Australia
| | | | - Diwei Ho
- School of Molecular Sciences, The University of Western Australia, Crawley, WA 6009, Australia
| | - Carole A Bartlett
- Curtin Health and Innovation Research Institute, Faculty of Health Sciences, Curtin University, Bentley, WA 6102, Australia
| | - Brooke Fehily
- Curtin Health and Innovation Research Institute, Faculty of Health Sciences, Curtin University, Bentley, WA 6102, Australia
- Perron Institute for Neurological and Translational Sciences, 8 Verdun Street, Nedlands, WA 6009, Australia
| | - Brittney R Lins
- Curtin Health and Innovation Research Institute, Faculty of Health Sciences, Curtin University, Bentley, WA 6102, Australia
- Perron Institute for Neurological and Translational Sciences, 8 Verdun Street, Nedlands, WA 6009, Australia
| | - Melinda Fitzgerald
- Curtin Health and Innovation Research Institute, Faculty of Health Sciences, Curtin University, Bentley, WA 6102, Australia
- Perron Institute for Neurological and Translational Sciences, 8 Verdun Street, Nedlands, WA 6009, Australia
| | - Mark J Hackett
- Curtin Health and Innovation Research Institute, Faculty of Health Sciences, Curtin University, Bentley, WA 6102, Australia
- School of Molecular and Life Sciences, Faculty of Science and Engineering, Curtin University, Bentley, WA 6102, Australia
| | - Nicole M Smith
- School of Molecular Sciences, The University of Western Australia, Crawley, WA 6009, Australia
| |
Collapse
|
3
|
Kwong JMK, Caprioli J, Lee JCY, Song Y, Yu FJ, Bian J, Sze YH, Li KK, Do CW, To CH, Lam TC. Differential Responses of Retinal Neurons and Glia Revealed via Proteomic Analysis on Primary and Secondary Retinal Ganglion Cell Degeneration. Int J Mol Sci 2023; 24:12109. [PMID: 37569482 PMCID: PMC10418669 DOI: 10.3390/ijms241512109] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2023] [Revised: 07/14/2023] [Accepted: 07/25/2023] [Indexed: 08/13/2023] Open
Abstract
To explore the temporal profile of retinal proteomes specific to primary and secondary retinal ganglion cell (RGC) loss. Unilateral partial optic nerve transection (pONT) was performed on the temporal side of the rat optic nerve. Temporal and nasal retinal samples were collected at 1, 4 and 8 weeks after pONT (n = 4 each) for non-biased profiling with a high-resolution hybrid quadrupole time-of-flight mass spectrometry running on label-free SWATHTM acquisition (SCIEX). An information-dependent acquisition ion library was generated using ProteinPilot 5.0 and OneOmics cloud bioinformatics. Combined proteome analysis detected 2531 proteins with a false discovery rate of <1%. Compared to the nasal retina, 10, 25 and 61 significantly regulated proteins were found in the temporal retina at 1, 4, and 8 weeks, respectively (p < 0.05, FC ≥ 1.4 or ≤0.7). Eight proteins (ALDH1A1, TRY10, GFAP, HBB-B1, ALB, CDC42, SNCG, NEFL) were differentially expressed for at least two time points. The expressions of ALDH1A1 and SNCG at nerve fibers were decreased along with axonal loss. Increased ALDH1A1 localization in the inner nuclear layer suggested stress response. Increased GFAP expression demonstrated regional reactivity of astrocytes and Muller cells. Meta-analysis of gene ontology showed a pronounced difference in endopeptidase and peptidase inhibitor activity. Temporal proteomic profiling demonstrates established and novel protein targets associated with RGC damage.
Collapse
Affiliation(s)
- Jacky M. K. Kwong
- Ophthalmology, Stein Eye Institute, University of California Los Angeles, Los Angeles, CA 90095, USA; (J.C.); (J.C.Y.L.); (Y.S.)
| | - Joseph Caprioli
- Ophthalmology, Stein Eye Institute, University of California Los Angeles, Los Angeles, CA 90095, USA; (J.C.); (J.C.Y.L.); (Y.S.)
| | - Joanne C. Y. Lee
- Ophthalmology, Stein Eye Institute, University of California Los Angeles, Los Angeles, CA 90095, USA; (J.C.); (J.C.Y.L.); (Y.S.)
| | - Yifan Song
- Ophthalmology, Stein Eye Institute, University of California Los Angeles, Los Angeles, CA 90095, USA; (J.C.); (J.C.Y.L.); (Y.S.)
| | - Feng-Juan Yu
- Centre for Myopia Research, School of Optometry, The Hong Kong Polytechnic University, Hong Kong, China; (F.-J.Y.); (J.B.); (Y.-H.S.); (K.-K.L.); (C.-W.D.); (C.-H.T.)
- Research Centre for SHARP Vision (RCSV), The Hong Kong Polytechnic University, Hong Kong, China
| | - Jingfang Bian
- Centre for Myopia Research, School of Optometry, The Hong Kong Polytechnic University, Hong Kong, China; (F.-J.Y.); (J.B.); (Y.-H.S.); (K.-K.L.); (C.-W.D.); (C.-H.T.)
- Research Centre for SHARP Vision (RCSV), The Hong Kong Polytechnic University, Hong Kong, China
| | - Ying-Hon Sze
- Centre for Myopia Research, School of Optometry, The Hong Kong Polytechnic University, Hong Kong, China; (F.-J.Y.); (J.B.); (Y.-H.S.); (K.-K.L.); (C.-W.D.); (C.-H.T.)
| | - King-Kit Li
- Centre for Myopia Research, School of Optometry, The Hong Kong Polytechnic University, Hong Kong, China; (F.-J.Y.); (J.B.); (Y.-H.S.); (K.-K.L.); (C.-W.D.); (C.-H.T.)
| | - Chi-Wai Do
- Centre for Myopia Research, School of Optometry, The Hong Kong Polytechnic University, Hong Kong, China; (F.-J.Y.); (J.B.); (Y.-H.S.); (K.-K.L.); (C.-W.D.); (C.-H.T.)
- Research Centre for SHARP Vision (RCSV), The Hong Kong Polytechnic University, Hong Kong, China
- Centre for Eye and Vision Research (CEVR), The Hong Kong Polytechnic University, 17W, Hong Kong Science Park, Hong Kong, China
| | - Chi-Ho To
- Centre for Myopia Research, School of Optometry, The Hong Kong Polytechnic University, Hong Kong, China; (F.-J.Y.); (J.B.); (Y.-H.S.); (K.-K.L.); (C.-W.D.); (C.-H.T.)
- Research Centre for SHARP Vision (RCSV), The Hong Kong Polytechnic University, Hong Kong, China
- Centre for Eye and Vision Research (CEVR), The Hong Kong Polytechnic University, 17W, Hong Kong Science Park, Hong Kong, China
| | - Thomas Chuen Lam
- Centre for Myopia Research, School of Optometry, The Hong Kong Polytechnic University, Hong Kong, China; (F.-J.Y.); (J.B.); (Y.-H.S.); (K.-K.L.); (C.-W.D.); (C.-H.T.)
- Research Centre for SHARP Vision (RCSV), The Hong Kong Polytechnic University, Hong Kong, China
- Centre for Eye and Vision Research (CEVR), The Hong Kong Polytechnic University, 17W, Hong Kong Science Park, Hong Kong, China
- Shenzhen Research Institute, The Hong Kong Polytechnic University, Shenzhen 518052, China
| |
Collapse
|
4
|
Miao Y, Zhao GL, Cheng S, Wang Z, Yang XL. Activation of retinal glial cells contributes to the degeneration of ganglion cells in experimental glaucoma. Prog Retin Eye Res 2023; 93:101169. [PMID: 36736070 DOI: 10.1016/j.preteyeres.2023.101169] [Citation(s) in RCA: 13] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2022] [Revised: 01/12/2023] [Accepted: 01/24/2023] [Indexed: 02/04/2023]
Abstract
Elevation of intraocular pressure (IOP) is a major risk factor for neurodegeneration in glaucoma. Glial cells, which play an important role in normal functioning of retinal neurons, are well involved into retinal ganglion cell (RGC) degeneration in experimental glaucoma animal models generated by elevated IOP. In response to elevated IOP, mGluR I is first activated and Kir4.1 channels are subsequently inhibited, which leads to the activation of Müller cells. Müller cell activation is followed by a complex process, including proliferation, release of inflammatory and growth factors (gliosis). Gliosis is further regulated by several factors. Activated Müller cells contribute to RGC degeneration through generating glutamate receptor-mediated excitotoxicity, releasing cytotoxic factors and inducing microglia activation. Elevated IOP activates microglia, and following morphological and functional changes, these cells, as resident immune cells in the retina, show adaptive immune responses, including an enhanced release of pro-inflammatory factors (tumor neurosis factor-α, interleukins, etc.). These ATP and Toll-like receptor-mediated responses are further regulated by heat shock proteins, CD200R, chemokine receptors, and metabotropic purinergic receptors, may aggravate RGC loss. In the optic nerve head, astrogliosis is initiated and regulated by a complex reaction process, including purines, transmitters, chemokines, growth factors and cytokines, which contributes to RGC axon injury through releasing pro-inflammatory factors and changing extracellular matrix in glaucoma. The effects of activated glial cells on RGCs are further modified by the interplay among different types of glial cells. This review is concluded by presenting an in-depth discussion of possible research directions in this field in the future.
Collapse
Affiliation(s)
- Yanying Miao
- State Key Laboratory of Medical Neurobiology and MOE Frontiers Center for Brain Science, Institutes of Brain Science, Fudan University, Shanghai, 200032, China
| | - Guo-Li Zhao
- State Key Laboratory of Medical Neurobiology and MOE Frontiers Center for Brain Science, Institutes of Brain Science, Fudan University, Shanghai, 200032, China
| | - Shuo Cheng
- State Key Laboratory of Medical Neurobiology and MOE Frontiers Center for Brain Science, Institutes of Brain Science, Fudan University, Shanghai, 200032, China
| | - Zhongfeng Wang
- State Key Laboratory of Medical Neurobiology and MOE Frontiers Center for Brain Science, Institutes of Brain Science, Fudan University, Shanghai, 200032, China.
| | - Xiong-Li Yang
- State Key Laboratory of Medical Neurobiology and MOE Frontiers Center for Brain Science, Institutes of Brain Science, Fudan University, Shanghai, 200032, China.
| |
Collapse
|
5
|
Secondary Degeneration of Oligodendrocyte Precursor Cells Occurs as Early as 24 h after Optic Nerve Injury in Rats. Int J Mol Sci 2023; 24:ijms24043463. [PMID: 36834873 PMCID: PMC9964292 DOI: 10.3390/ijms24043463] [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: 12/22/2022] [Revised: 02/06/2023] [Accepted: 02/07/2023] [Indexed: 02/11/2023] Open
Abstract
Optic nerve injury causes secondary degeneration, a sequela that spreads damage from the primary injury to adjacent tissue, through mechanisms such as oxidative stress, apoptosis, and blood-brain barrier (BBB) dysfunction. Oligodendrocyte precursor cells (OPCs), a key component of the BBB and oligodendrogenesis, are vulnerable to oxidative deoxyribonucleic acid (DNA) damage by 3 days post-injury. However, it is unclear whether oxidative damage in OPCs occurs earlier at 1 day post-injury, or whether a critical 'window-of-opportunity' exists for therapeutic intervention. Here, a partial optic nerve transection rat model of secondary degeneration was used with immunohistochemistry to assess BBB dysfunction, oxidative stress, and proliferation in OPCs vulnerable to secondary degeneration. At 1 day post-injury, BBB breach and oxidative DNA damage were observed, alongside increased density of DNA-damaged proliferating cells. DNA-damaged cells underwent apoptosis (cleaved caspase3+), and apoptosis was associated with BBB breach. OPCs experienced DNA damage and apoptosis and were the major proliferating cell type with DNA damage. However, the majority of caspase3+ cells were not OPCs. These results provide novel insights into acute secondary degeneration mechanisms in the optic nerve, highlighting the need to consider early oxidative damage to OPCs in therapeutic efforts to limit degeneration following optic nerve injury.
Collapse
|
6
|
Lins BR, Anyaegbu CC, McGonigle T, Hellewell SC, Patel P, Reagan H, Rooke-Wiesner C, Warnock A, Archer M, Hemmi JM, Bartlett C, Fitzgerald M. Secondary Degeneration Impairs Myelin Ultrastructural Development in Adulthood following Adolescent Neurotrauma in the Rat Optic Nerve. Int J Mol Sci 2023; 24:ijms24043343. [PMID: 36834755 PMCID: PMC9966883 DOI: 10.3390/ijms24043343] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2022] [Revised: 01/31/2023] [Accepted: 02/01/2023] [Indexed: 02/10/2023] Open
Abstract
Adolescence is a critical period of postnatal development characterized by social, emotional, and cognitive changes. These changes are increasingly understood to depend on white matter development. White matter is highly vulnerable to the effects of injury, including secondary degeneration in regions adjacent to the primary injury site which alters the myelin ultrastructure. However, the impact of such alterations on adolescent white matter maturation is yet to be investigated. To address this, female piebald-virol-glaxo rats underwent partial transection of the optic nerve during early adolescence (postnatal day (PND) 56) with tissue collection two weeks (PND 70) or three months later (PND 140). Axons and myelin in the transmission electron micrographs of tissue adjacent to the injury were classified and measured based on the appearance of the myelin laminae. Injury in adolescence impaired the myelin structure in adulthood, resulting in a lower percentage of axons with compact myelin and a higher percentage of axons with severe myelin decompaction. Myelin thickness did not increase as expected into adulthood after injury and the relationship between the axon diameter and myelin thickness in adulthood was altered. Notably, dysmyelination was not observed 2 weeks postinjury. In conclusion, injury in adolescence altered the developmental trajectory, resulting in impaired myelin maturation when assessed at the ultrastructural level in adulthood.
Collapse
Affiliation(s)
- Brittney R. Lins
- Curtin Health Innovation Research Institute, Curtin University, Bentley, WA 6845, Australia
- Perron Institute for Neurological and Translational Sciences, Nedlands, WA 6009, Australia
| | - Chidozie C. Anyaegbu
- Curtin Health Innovation Research Institute, Curtin University, Bentley, WA 6845, Australia
- Perron Institute for Neurological and Translational Sciences, Nedlands, WA 6009, Australia
- Correspondence:
| | - Terence McGonigle
- Curtin Health Innovation Research Institute, Curtin University, Bentley, WA 6845, Australia
- Perron Institute for Neurological and Translational Sciences, Nedlands, WA 6009, Australia
| | - Sarah C. Hellewell
- Curtin Health Innovation Research Institute, Curtin University, Bentley, WA 6845, Australia
- Perron Institute for Neurological and Translational Sciences, Nedlands, WA 6009, Australia
| | - Parth Patel
- Curtin Health Innovation Research Institute, Curtin University, Bentley, WA 6845, Australia
- Perron Institute for Neurological and Translational Sciences, Nedlands, WA 6009, Australia
| | - Harry Reagan
- School of Biological Sciences, The University of Western Australia, Perth, WA 6009, Australia
| | - Cara Rooke-Wiesner
- Curtin Health Innovation Research Institute, Curtin University, Bentley, WA 6845, Australia
- Perron Institute for Neurological and Translational Sciences, Nedlands, WA 6009, Australia
| | - Andrew Warnock
- Curtin Health Innovation Research Institute, Curtin University, Bentley, WA 6845, Australia
- Perron Institute for Neurological and Translational Sciences, Nedlands, WA 6009, Australia
| | - Michael Archer
- Curtin Health Innovation Research Institute, Curtin University, Bentley, WA 6845, Australia
- Perron Institute for Neurological and Translational Sciences, Nedlands, WA 6009, Australia
| | - Jan M. Hemmi
- School of Biological Sciences, The University of Western Australia, Perth, WA 6009, Australia
- Oceans Institute, The University of Western Australia, Perth, WA 6009, Australia
| | - Carole Bartlett
- Curtin Health Innovation Research Institute, Curtin University, Bentley, WA 6845, Australia
- Perron Institute for Neurological and Translational Sciences, Nedlands, WA 6009, Australia
| | - Melinda Fitzgerald
- Curtin Health Innovation Research Institute, Curtin University, Bentley, WA 6845, Australia
- Perron Institute for Neurological and Translational Sciences, Nedlands, WA 6009, Australia
| |
Collapse
|
7
|
Sun W, Chao G, Shang M, Wu Q, Xia Y, Wei Q, Zhou J, Liao L. Optic nerve injury models under varying forces. Int Ophthalmol 2022; 43:757-769. [PMID: 36038691 PMCID: PMC10042766 DOI: 10.1007/s10792-022-02476-2] [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: 05/05/2022] [Accepted: 08/20/2022] [Indexed: 11/25/2022]
Abstract
PURPOSE To explore the pathological changes in optic nerve injury models under varying forces. METHODS The rats were classified into 4 groups: sham operation (SH), 0.1, 0.3, and 0.5 N. Modeling was performed using the lateral optic nerve pulling method. Seven days after modeling, Brn3a immunofluorescence was used to detect retinal ganglion cell (RGC) number, terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) staining was used to detect RGC apoptosis, and flash visual evoked potential (FVEP) was used to detect the optic nerve function on days 1, 3, and 7 after modeling. In addition, LC3 II and P62 expression levels in retinal tissues were detected by western blotting to observe the changes in autophagy levels. RESULTS RGC number decreased 7 d after modeling, and it showed a downward trend with increasing damaging force. The number of apoptotic RGCs in ganglion cell layer in the 0.3 and 0.5 N groups was increased and was higher than that in the 0.1 N group. The difference in FVEP of rats in each group was mainly reflected in the P2 peak latency. LC3 II and P62 expression levels in retinal tissue of 0.3 and 0.5 N groups were higher than those of the SH and 0.1 groups; however, the difference between the 0.1 N and SH groups was not statistically significant. CONCLUSION Precisely controlling the force of the optic nerve clamping injury model is necessary because different forces acting on the optic nerve will lead to differences in the loss of optic neurons, the conduction function of the optic nerve, and autophagy level in retinal tissues.
Collapse
Affiliation(s)
- Wu Sun
- Beijing University of Chinese Medicine, Beijing, China
| | - Guojun Chao
- Eye Hospital Chinese Academy of Chinese Medical Sciences, Beijing, China
| | - Mengqiu Shang
- Beijing University of Chinese Medicine, Beijing, China
| | - Qiong Wu
- Beijing Tongren Hospital, Beijing, China
| | - Yanting Xia
- Dongfang Hospital Beijing University of Chinese Medicine, Beijing, China
| | - Qiping Wei
- Dongfang Hospital Beijing University of Chinese Medicine, Beijing, China
| | - Jian Zhou
- Beijing University of Chinese Medicine, Beijing, China.
- Dongfang Hospital Beijing University of Chinese Medicine, Beijing, China.
- Department of Ophthalmology, Dongfang Hospital, Beijing University of Chinese Medicine, Beijing, 100078, China.
- , No. 6, District 1, Fangxing Garden, Fangzhuang, Fengtai District, Beijing, 100078, China.
| | - Liang Liao
- Beijing University of Chinese Medicine, Beijing, China.
- Dongfang Hospital Beijing University of Chinese Medicine, Beijing, China.
- Department of Ophthalmology, Dongfang Hospital, Beijing University of Chinese Medicine, Beijing, 100078, China.
- , No. 6, District 1, Fangxing Garden, Fangzhuang, Fengtai District, Beijing, 100078, China.
| |
Collapse
|
8
|
Yan F, Wang X, Jiang X, Chai Y, Zhang J, Liu Q, Wu S, Wang Y, Wang N, Li S. Proteomic profiles of the retina in an experimental unilateral optic nerve transection: Roles of Müller cell activation. Clin Transl Med 2022; 12:e631. [PMID: 35474440 PMCID: PMC9043120 DOI: 10.1002/ctm2.631] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2021] [Revised: 09/20/2021] [Accepted: 10/11/2021] [Indexed: 11/06/2022] Open
Affiliation(s)
- Fancheng Yan
- Department of Ophthalmology, Beijing Friendship Hospital, Capital Medical University, Beijing, China
| | - Xiaolei Wang
- Department of Ophthalmology, Beijing Friendship Hospital, Capital Medical University, Beijing, China
| | - Xian Jiang
- Department of Ophthalmology, Anhui No. 2 Provincial People's Hospital, Hefei, Anhui Province, China
| | - Yijie Chai
- Department of Pathology, School of Basic Medical Sciences, Peking University Health Science Center, Beijing, China
| | - Jingxue Zhang
- Beijing Institute of Ophthalmology, Beijing Tongren Eye Center, Beijing Tongren Hospital, Capital Medical University, Beijing Ophthalmology & Visual Sciences Key Laboratory, Beijing, China.,Beijing Institute of Brain Disorders, Collaborative Innovation Center for Brain Disorders, Capital Medical University, Beijing, China
| | - Qian Liu
- Beijing Institute of Ophthalmology, Beijing Tongren Eye Center, Beijing Tongren Hospital, Capital Medical University, Beijing Ophthalmology & Visual Sciences Key Laboratory, Beijing, China
| | - Shen Wu
- Beijing Institute of Ophthalmology, Beijing Tongren Eye Center, Beijing Tongren Hospital, Capital Medical University, Beijing Ophthalmology & Visual Sciences Key Laboratory, Beijing, China
| | - Yanling Wang
- Department of Ophthalmology, Beijing Friendship Hospital, Capital Medical University, Beijing, China
| | - Ningli Wang
- Beijing Institute of Ophthalmology, Beijing Tongren Eye Center, Beijing Tongren Hospital, Capital Medical University, Beijing Ophthalmology & Visual Sciences Key Laboratory, Beijing, China.,Beijing Institute of Brain Disorders, Collaborative Innovation Center for Brain Disorders, Capital Medical University, Beijing, China
| | - Shuning Li
- Department of Ophthalmology, Beijing Tongren Eye Center, Beijing Tongren Hospital, Capital Medical University, Beijing Ophthalmology & Visual Sciences Key Laboratory, Beijing, China
| |
Collapse
|
9
|
Molecular regulation of neuroinflammation in glaucoma: Current knowledge and the ongoing search for new treatment targets. Prog Retin Eye Res 2022; 87:100998. [PMID: 34348167 PMCID: PMC8803988 DOI: 10.1016/j.preteyeres.2021.100998] [Citation(s) in RCA: 53] [Impact Index Per Article: 26.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2021] [Revised: 07/23/2021] [Accepted: 07/26/2021] [Indexed: 12/11/2022]
Abstract
Neuroinflammation relying on the inflammatory responses of glial cells has emerged as an impactful component of the multifactorial etiology of neurodegeneration in glaucoma. It has become increasingly evident that despite early adaptive and reparative features of glial responses, prolonged reactivity of the resident glia, along with the peripheral immune cells, create widespread toxicity to retinal ganglion cell (RGC) axons, somas, and synapses. As much as the synchronized responses of astrocytes and microglia to glaucoma-related stress or neuron injury, their bi-directional interactions are critical to build and amplify neuroinflammation and to dictate the neurodegenerative outcome. Although distinct molecular programs regulate somatic and axonal degeneration in glaucoma, inhibition of neurodegenerative inflammation can provide a broadly beneficial treatment strategy to rescue RGC integrity and function. Since inflammatory toxicity and mitochondrial dysfunction are converging etiological paths that can boost each other and feed into a vicious cycle, anti-inflammatory treatments may also offer a multi-target potential. This review presents an overview of the current knowledge on neuroinflammation in glaucoma with particular emphasis on the cell-intrinsic and cell-extrinsic factors involved in the reciprocal regulation of glial responses, the interdependence between inflammatory and mitochondrial routes of neurodegeneration, and the research aspects inspiring for prospective immunomodulatory treatments. With the advent of powerful technologies, ongoing research on molecular and functional characteristics of glial responses is expected to accumulate more comprehensive and complementary information and to rapidly move the field forward to safe and effective modulation of the glial pro-inflammatory activities, while restoring or augmenting the glial immune-regulatory and neurosupport functions.
Collapse
|
10
|
Construction and analysis of mRNA, lncRNA, and transcription factor regulatory networks after retinal ganglion cell injury. Exp Eye Res 2021; 215:108915. [PMID: 34971620 DOI: 10.1016/j.exer.2021.108915] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2021] [Revised: 12/11/2021] [Accepted: 12/23/2021] [Indexed: 12/11/2022]
Abstract
Retinal ganglion cell (RGC) injury is a critical pathological feature of several optic neurodegenerative diseases. The regulatory mechanisms underlying RGC injury remain poorly understood. Recent evidence has highlighted the important roles of long noncoding RNAs (lncRNAs) in degenerative neuropathy but few studies have focused on lncRNAs associated with RGC injury. In this study, we analyzed dysregulated lncRNAs associated with RGC injury, their potential regulatory functions, and the molecular mechanisms underlying the regulation of lncRNAs and transcription factors (TFs). We analyzed lncRNA and mRNA profiles in the GSE142881 dataset associated with RGC injury and identified 1049 differentially expressed genes (DEGs), with 18 differentially expressed (DE) TFs among 883 DE mRNAs and 312 DE lncRNAs. The predicted DE lncRNAs and DE mRNAs were used to construct a lncRNA-mRNA co-expression network. Functional enrichment analysis was performed to explore the functions of the lncRNAs and mRNAs. The co-expression network between DE lncRNAs and DE mRNAs was highly enriched in inflammatory and immune-related pathways, indicating that they play role in the process of RGC injury. Among the DE mRNAs, we screened 18 DE TFs, including activating transcription factor 3 (ATF3), associated with RGC injury. Co-expression analysis predicted that 13 lncRNAs were potential binding targets of ATF3. The screening of the potential targets of these 13 lncRNAs showed that they were also significantly enriched in functional pathways associated with inflammation and apoptosis. After analysis, we constructed the mRNA-ATF3-lncRNA regulatory network after RGCs injury. In summary, we identified the gene module associated with immune and inflammatory responses after optic nerve injury and constructed a regulatory network of lncRNA-TF-mRNA. The results indicate that lncRNAs, by binding to TFs, can regulate downstream genes and function during RGC injury. The results provide a foundation for further studies of the mechanism of RGC injury and provide insight into the clinical diagnosis and investigation direction of neurodegenerative diseases such as traumatic optic neuropathy and glaucoma.
Collapse
|
11
|
Mishra S, Singh VJ, Chawla PA, Chawla V. Neuroprotective Role of Nutritional Supplementation in Athletes. Curr Mol Pharmacol 2021; 15:129-142. [PMID: 34886789 DOI: 10.2174/1874467214666211209144721] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2021] [Revised: 06/22/2021] [Accepted: 08/31/2021] [Indexed: 11/22/2022]
Abstract
BACKGROUND Neurodegenerative disorders belong to different classes of progressive/chronic conditions that affect the peripheral/central nervous system. It has been shown through studies that athletes who play sports involving repeated head trauma and sub-concussive impacts are more likely to experience neurological impairments and neurodegenerative disorders in the long run. AIMS The aim of the current narrative review article is to provide a summary of various nutraceuticals that offer promise in the prevention or management of sports-related injuries, especially concussions and mild traumatic brain injuries. METHODS This article reviews the various potential nutraceutical agents and their possible mechanisms in providing a beneficial effect in the injury recovery process. A thorough survey of the literature was carried out in the relevant databases to identify studies published in recent years. In the present article, we have also highlighted the major neurological disorders along with the associated nutraceutical(s) therapy in the management of disorders. RESULTS The exact pathological mechanism behind neurodegenerative conditions is complex as well as idiopathic. However, mitochondrial dysfunction, oxidative stress as well as intracellular calcium overload are some common reasons responsible for the progression of these neurodegenerative disorders. Owing to the multifaceted effects of nutraceuticals (complementary medicine), these supplements have gained importance as neuroprotective. These diet-based approaches inhibit different pathways in a physiological manner without eliciting adverse effects. Food habits and lifestyle of an individual also affect neurodegeneration. CONCLUSION Studies have shown nutraceuticals (such as resveratrol, omega-3-fatty acids) to be efficacious in terms of their neuroprotection against several neurodegenerative disorders and to be used as supplements in the management of traumatic brain injuries. Protection prior to injuries is needed since concussions or sub-concussive impacts may trigger several pathophysiological responses or cascades that can lead to long-term complications associated with CNS. Thus, the use of nutraceuticals as prophylactic treatment for neurological interventions has been proposed.
Collapse
Affiliation(s)
- Supriya Mishra
- Department of Pharmacology, SRM College of Pharmacy, Delhi-NCR. India
| | - Vikram Jeet Singh
- Department of Pharmaceutical Chemistry and Analysis, ISF College of Pharmacy, Moga-142001, Punjab. India
| | - Pooja A Chawla
- Department of Pharmaceutical Chemistry and Analysis, ISF College of Pharmacy, Moga-142001, Punjab. India
| | - Viney Chawla
- Department of Pharmaceutics, University Institute of Pharmaceutical Sciences and Research, Baba Farid University of Health Sciences, Faridkot-151203, Punjab. India
| |
Collapse
|
12
|
Xing Y, Liang S, Zhao Y, Yang S, Ni H, Li H. Protection of Aronia melanocarpa Fruit Extract from Sodium-Iodate-Induced Damages in Rat Retina. Nutrients 2021; 13:4411. [PMID: 34959962 PMCID: PMC8703977 DOI: 10.3390/nu13124411] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2021] [Revised: 12/07/2021] [Accepted: 12/08/2021] [Indexed: 11/16/2022] Open
Abstract
Age-related macular degeneration (AMD) is one of the major causes of blindness in elderly populations. However, the dry form of AMD has lack of effective treatments. The fruits of Aronia melanocarpa are rich in anthocyanins. In this study, the protective effects of aronia fruit extract on rat retina were investigated using a NaIO3-induced dry AMD model. Full-field electroretinograms (ERGs) showed that b-wave amplitudes were significantly decreased and the retina structures were disordered in the model. The extract treatment alleviated the injuries. The b-wave amplitudes increased 61.5% in Scotopic 0.01ERG, 122.0% in Photopic 3.0ERG, and 106.8% in Photopic 3.0 flicker; the retina structure disorder was improved with the thickness of outer nuclear layer increasing by 44.1%; and the malonaldehyde level was significantly reduced in extract-treated rat retinas compared to the model. The proteomics analysis showed the expressions of five crystallin proteins, α-crystallin A chain, β-crystallin B2, β-crystallin A3, α-crystallin B chain, and γ-crystallin S, which protect retina ganglion cells, were increased by 7.38-, 7.74-, 15.30-, 4.86-, and 9.14-fold, respectively, in the extract treatment compared to the control, which was also confirmed by immunoblotting. The results suggest that aronia fruit extract, probably due to its anthocyanins, could protect the rat retina by alleviating oxidative damages and by upregulating the crystallin proteins to protect its nerve system.
Collapse
Affiliation(s)
- Yan Xing
- Guangdong Provincial Key Lab of Biotechnology for Plant Development, School of Life Sciences, South China Normal University, Guangzhou 510631, China; (Y.X.); (H.N.)
| | - Shan Liang
- Key Laboratory of Microbial Physiological and Metabolic Engineering, Institute of Microbiology, Chinese Academy of Sciences, Beijing 100101, China;
| | - Yuanyuan Zhao
- State Key Laboratory of Proteomics, Beijing Proteome Research Center, Institute of Lifeomics, National Center for Protein Sciences (The PHOENIX Center), Beijing 102206, China;
| | - Shuo Yang
- Guozhen Health Technology (Beijing) Co., Ltd., Beijing 102206, China;
| | - He Ni
- Guangdong Provincial Key Lab of Biotechnology for Plant Development, School of Life Sciences, South China Normal University, Guangzhou 510631, China; (Y.X.); (H.N.)
| | - Haihang Li
- Guangdong Provincial Key Lab of Biotechnology for Plant Development, School of Life Sciences, South China Normal University, Guangzhou 510631, China; (Y.X.); (H.N.)
| |
Collapse
|
13
|
Kang EYC, Liu PK, Wen YT, Quinn PMJ, Levi SR, Wang NK, Tsai RK. Role of Oxidative Stress in Ocular Diseases Associated with Retinal Ganglion Cells Degeneration. Antioxidants (Basel) 2021; 10:1948. [PMID: 34943051 PMCID: PMC8750806 DOI: 10.3390/antiox10121948] [Citation(s) in RCA: 30] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2021] [Revised: 11/25/2021] [Accepted: 12/02/2021] [Indexed: 12/12/2022] Open
Abstract
Ocular diseases associated with retinal ganglion cell (RGC) degeneration is the most common neurodegenerative disorder that causes irreversible blindness worldwide. It is characterized by visual field defects and progressive optic nerve atrophy. The underlying pathophysiology and mechanisms of RGC degeneration in several ocular diseases remain largely unknown. RGCs are a population of central nervous system neurons, with their soma located in the retina and long axons that extend through the optic nerve to form distal terminals and connections in the brain. Because of this unique cytoarchitecture and highly compartmentalized energy demand, RGCs are highly mitochondrial-dependent for adenosine triphosphate (ATP) production. Recently, oxidative stress and mitochondrial dysfunction have been found to be the principal mechanisms in RGC degeneration as well as in other neurodegenerative disorders. Here, we review the role of oxidative stress in several ocular diseases associated with RGC degenerations, including glaucoma, hereditary optic atrophy, inflammatory optic neuritis, ischemic optic neuropathy, traumatic optic neuropathy, and drug toxicity. We also review experimental approaches using cell and animal models for research on the underlying mechanisms of RGC degeneration. Lastly, we discuss the application of antioxidants as a potential future therapy for the ocular diseases associated with RGC degenerations.
Collapse
Affiliation(s)
- Eugene Yu-Chuan Kang
- Department of Ophthalmology, Linkou Chang Gung Memorial Hospital, Taoyuan 33302, Taiwan;
- Graduate Institute of Clinical Medical Sciences, College of Medicine, Chang Gung University, Taoyuan 33302, Taiwan
| | - Pei-Kang Liu
- Department of Ophthalmology, Kaohsiung Medical University Hospital, Kaohsiung 80424, Taiwan;
- School of Medicine, College of Medicine, Kaohsiung Medical University, Kaohsiung 80424, Taiwan
- Institute of Biomedical Sciences, National Sun Yat-sen University, Kaohsiung 80424, Taiwan
- Edward S. Harkness Eye Institute, Department of Ophthalmology, Columbia University Irving Medical Center, New York, NY 10032, USA
| | - Yao-Tseng Wen
- Institute of Eye Research, Hualien Tzu Chi Hospital, Buddhist Tzu Chi Medical Foundation, Hualien 97403, Taiwan;
| | - Peter M. J. Quinn
- Jonas Children’s Vision Care, and Bernard and Shirlee Brown Glaucoma Laboratory, Columbia Stem Cell Initiative, Departments of Ophthalmology, Pathology and Cell Biology, Institute of Human Nutrition, Vagelos College of Physicians and Surgeons, Columbia University, New York, NY 10032, USA; (P.M.J.Q.); (S.R.L.)
| | - Sarah R. Levi
- Jonas Children’s Vision Care, and Bernard and Shirlee Brown Glaucoma Laboratory, Columbia Stem Cell Initiative, Departments of Ophthalmology, Pathology and Cell Biology, Institute of Human Nutrition, Vagelos College of Physicians and Surgeons, Columbia University, New York, NY 10032, USA; (P.M.J.Q.); (S.R.L.)
| | - Nan-Kai Wang
- Edward S. Harkness Eye Institute, Department of Ophthalmology, Columbia University Irving Medical Center, New York, NY 10032, USA
| | - Rong-Kung Tsai
- Institute of Eye Research, Hualien Tzu Chi Hospital, Buddhist Tzu Chi Medical Foundation, Hualien 97403, Taiwan;
- Institute of Medical Sciences, Tzu Chi University, Hualien 97403, Taiwan
| |
Collapse
|
14
|
Kwong JMK, Caprioli J, Sze YH, Yu FJ, Li KK, To CH, Lam TC. Differential Retinal Protein Expression in Primary and Secondary Retinal Ganglion Cell Degeneration Identified by Integrated SWATH and Target-Based Proteomics. Int J Mol Sci 2021; 22:ijms22168592. [PMID: 34445296 PMCID: PMC8395271 DOI: 10.3390/ijms22168592] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2021] [Revised: 08/06/2021] [Accepted: 08/08/2021] [Indexed: 12/15/2022] Open
Abstract
To investigate the retinal proteins associated with primary and secondary retinal ganglion cell (RGC) degeneration and explore their molecular pathways, SWATH label-free and target-based mass spectrometry was employed to identify the proteomes in various retinal locations in response to localized optic nerve injury. Unilateral partial optic nerve transection (pONT) was performed on adult Wistar rats and their retinas were harvested 2 weeks later. To confirm the separation of primary and secondary RGC degeneration, immunohistochemistry of RNA binding protein with multiple splicing (RBPMS) and glial fibrillary acidic protein (GFAP) was performed on retinal whole-mounts. Retinal proteomes in the temporal and nasal quadrants were evaluated with high resolution hybrid quadrupole time-of-flight mass spectrometry (QTOF-MS), and SWATH-based acquisition, and their expression was compared to the corresponding retinal quadrant in contralateral control eyes and further validated by multiple reaction monitoring mass spectrometry (MRM-MS). A total of 3641 proteins (FDR < 1%) were identified using QTOF-MS. The raw data are available via ProteomeXchange with the identifier PXD026783. Bioinformatics data analysis showed that there were 37 upregulated and 25 downregulated proteins in the temporal quadrant, whereas 20 and five proteins were upregulated and downregulated, respectively, in the nasal quadrant, respectively (n = 4, p < 0.05; fold change ≥ 1.4-fold or ≤0.7). Six proteins were regulated in both the temporal and the nasal quadrants, including CLU, GFAP, GNG5, IRF2BPL, L1CAM, and CPLX1. Linear regression analysis indicated a strong association between the data obtained by means of SWATH-MS and MRM-MS (temporal, R2 = 0.97; nasal, R2 = 0.96). Gene ontology analysis revealed statistically significant changes in the biological processes and cellular components of primary RGC degeneration. The majority of the significant changes in structural, signaling, and cell death proteins were associated with the loss of RGCs in the area of primary RGC degeneration. The combined use of SWATH-MS and MRM-MS methods detects and quantifies regional changes of retinal protein expressions after localized injury. Future investigation with this integrated approach will significantly increase the understanding of diverse processes of progressive RGC degeneration from a proteomic prospective.
Collapse
Affiliation(s)
- Jacky M. K. Kwong
- Department of Ophthalmology, Stein Eye Institute, David Geffen School of Medicine, University of California Los Angeles, Los Angeles, CA 90095, USA;
- Correspondence: (J.M.K.K.); (T.C.L.)
| | - Joseph Caprioli
- Department of Ophthalmology, Stein Eye Institute, David Geffen School of Medicine, University of California Los Angeles, Los Angeles, CA 90095, USA;
| | - Ying H. Sze
- Centre for Myopia Research, School of Optometry, The Hong Kong Polytechnic University, Hong Kong 999077, China; (Y.H.S.); (F.J.Y.); (K.K.L.); (C.H.T.)
- Centre for Eye and Vision Science, School of Optometry, The Hong Kong Polytechnic University, Hong Kong 999077, China
| | - Feng J. Yu
- Centre for Myopia Research, School of Optometry, The Hong Kong Polytechnic University, Hong Kong 999077, China; (Y.H.S.); (F.J.Y.); (K.K.L.); (C.H.T.)
- Centre for Eye and Vision Science, School of Optometry, The Hong Kong Polytechnic University, Hong Kong 999077, China
| | - King K. Li
- Centre for Myopia Research, School of Optometry, The Hong Kong Polytechnic University, Hong Kong 999077, China; (Y.H.S.); (F.J.Y.); (K.K.L.); (C.H.T.)
- Centre for Eye and Vision Science, School of Optometry, The Hong Kong Polytechnic University, Hong Kong 999077, China
| | - Chi H. To
- Centre for Myopia Research, School of Optometry, The Hong Kong Polytechnic University, Hong Kong 999077, China; (Y.H.S.); (F.J.Y.); (K.K.L.); (C.H.T.)
- Centre for Eye and Vision Science, School of Optometry, The Hong Kong Polytechnic University, Hong Kong 999077, China
- Shenzhen Research Institute, The Hong Kong Polytechnic University, Shenzhen 518052, China
| | - Thomas C. Lam
- Centre for Myopia Research, School of Optometry, The Hong Kong Polytechnic University, Hong Kong 999077, China; (Y.H.S.); (F.J.Y.); (K.K.L.); (C.H.T.)
- Centre for Eye and Vision Science, School of Optometry, The Hong Kong Polytechnic University, Hong Kong 999077, China
- Shenzhen Research Institute, The Hong Kong Polytechnic University, Shenzhen 518052, China
- Correspondence: (J.M.K.K.); (T.C.L.)
| |
Collapse
|
15
|
Anyaegbu CC, Mao Y, McGonigle T, Raja S, Clarke T, Black AMB, Solomon T, Fuller K, Fitzgerald M. Simultaneous flow cytometric characterization of multiple cell types and metabolic states in the rat brain after repeated mild traumatic brain injury. J Neurosci Methods 2021; 359:109223. [PMID: 34004202 DOI: 10.1016/j.jneumeth.2021.109223] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2021] [Revised: 05/11/2021] [Accepted: 05/11/2021] [Indexed: 12/18/2022]
Abstract
BACKGROUND Cellular responses at the sub-acute phase of mild traumatic brain injury (mTBI), and their contribution to ongoing damage, are unclear, complex and require simultaneous assessment of multiple cells to elucidate. NEW METHOD An 11-colour flow cytometry method for analysing brain cells was evaluated in a weight-drop rat model of repeated mTBI. Animals received sham, one, two or three mTBI delivered at 24 h intervals (n = 6/group). Cerebrum homogenates were prepared 11 days after first mTBI, in two cohorts of n = 3/group to enable same-day staining of fresh tissue. Percentages of neurons, astrocytes, microglia, mature oligodendrocytes and NeuN + CC1+ cells, neutrophils, macrophages and non-myeloid leukocytes, and their immunoreactivity for cell damage indicators (inducible nitric oxide synthase; iNOS, proliferating cell nuclear antigen; PCNA, 8-Oxo-2'-deoxyguanosine; 8OHDG and 4-hydroxynonenal; HNE), were assessed. RESULTS Median fluorescence intensity (MFI) of iNOS in activated microglia increased following two, but not one or three, mTBI (p = 0.04). However, there were differences between processing cohorts in terms of percentages and MFI of some PCNA+, iNOS+, 8OHDG + and HNE + cell populations. COMPARISON WITH EXISTING METHODS Previous applications of flow cytometry for rat brain analysis were typically limited to three or four markers. This method uses 11 markers to identify nine cell populations and evaluate their immunoreactivity to four metabolic indicators of cell damage. CONCLUSIONS Flow cytometry can be useful for discerning injury-related changes in multiple rat brain cells. However, markers sensitive to subtle changes in experimental conditions must be identified in pilot experiments and subsequently analysed in the same tissue-processing cohort.
Collapse
Affiliation(s)
- Chidozie C Anyaegbu
- Curtin Health Innovation Research Institute, Curtin University, Belmont, Western Australia, Australia.
| | - Yilin Mao
- Curtin Health Innovation Research Institute, Curtin University, Belmont, Western Australia, Australia
| | - Terry McGonigle
- Curtin Health Innovation Research Institute, Curtin University, Belmont, Western Australia, Australia
| | - Sushmitha Raja
- Curtin Health Innovation Research Institute, Curtin University, Belmont, Western Australia, Australia
| | - Thomas Clarke
- Curtin Health Innovation Research Institute, Curtin University, Belmont, Western Australia, Australia
| | - Anna M B Black
- Curtin Health Innovation Research Institute, Curtin University, Belmont, Western Australia, Australia
| | - Tanya Solomon
- Curtin Health Innovation Research Institute, Curtin University, Belmont, Western Australia, Australia
| | - Kathy Fuller
- Division of Cancer Biology, School of Biomedical Sciences, The University of Western Australia, 35 Stirling Hwy, Nedlands 6009 Western Australia, Australia
| | - Melinda Fitzgerald
- Curtin Health Innovation Research Institute, Curtin University, Belmont, Western Australia, Australia; Perron Institute for Neurological and Translational Science, Sarich Neuroscience Research Institute Building, 8 Verdun St, Nedlands 6009 Western Australia, Australia
| |
Collapse
|
16
|
O'Hare Doig RL, Santhakumar S, Fehily B, Raja S, Solomon T, Bartlett CA, Fitzgerald M, Hodgetts SI. Acute Cellular and Functional Changes With a Combinatorial Treatment of Ion Channel Inhibitors Following Spinal Cord Injury. Front Mol Neurosci 2020; 13:85. [PMID: 32670018 PMCID: PMC7331598 DOI: 10.3389/fnmol.2020.00085] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2019] [Accepted: 04/24/2020] [Indexed: 01/12/2023] Open
Abstract
Reducing the extent of secondary degeneration following spinal cord injury (SCI) is necessary to preserve function, but treatment options have thus far been limited. A combination of the ion channel inhibitors Lomerizine (Lom), YM872 and oxATP, to inhibit voltage-gated Ca2+ channels, Ca2+ permeable AMPA receptors, and purinergic P2X7 receptors respectively, effectively limits secondary consequences of injury in in vitro and in vivo models of CNS injury. Here, we investigated the efficacy of these inhibitors in a clinically relevant model of SCI. Fischer (F344) rats were subjected to a moderate (150 kD) contusive SCI at thoracic level T10 and assessed at 2 weeks or 10 weeks post-injury. Lom was delivered orally twice daily and YM872 and oxATP were delivered via osmotic mini-pump implanted at the time of SCI until 2 weeks following injury. Open field locomotion analysis revealed that treatment with the three inhibitors in combination improved the rate of functional recovery of the hind limb (compared to controls) as early as 1-day post-injury, with beneficial effects persisting to 14 days post-injury, while all three inhibitors were present. At 2 weeks following combinatorial treatment, the functional improvement was associated with significantly decreased cyst size, increased immunoreactivity of β-III tubulin+ve axons, myelin basic protein, and reduced lipid peroxidation by-products, and increased CC1+ve oligodendrocytes and NG2+ve/PDGFα+ve oligodendrocyte progenitor cell densities, compared to vehicle-treated SCI animals. The combination of Lom, oxATP, and YM872 shows preclinical promise for control of secondary degeneration following SCI, and further investigation of long-term sustained treatment is warranted.
Collapse
Affiliation(s)
- Ryan L O'Hare Doig
- Experimental and Regenerative Neurosciences, School of Biological Sciences, The University of Western Australia, Crawley, WA, Australia.,Experimental and Regenerative Neurosciences, School of Human Sciences, The University of Western Australia, Crawley, WA, Australia.,Neil Sachse Centre for Spinal Cord Research, South Australian Health and Medical Research Institute, Adelaide, SA, Australia.,Adelaide Spinal Research Group, Faculty of Health and Medical Sciences, The University of Adelaide, Adelaide, SA, Australia
| | - Sreya Santhakumar
- Experimental and Regenerative Neurosciences, School of Human Sciences, The University of Western Australia, Crawley, WA, Australia.,Perron Institute for Neurological and Translational Science, Nedlands, WA, Australia
| | - Brooke Fehily
- Experimental and Regenerative Neurosciences, School of Biological Sciences, The University of Western Australia, Crawley, WA, Australia
| | - Sushmitha Raja
- Experimental and Regenerative Neurosciences, School of Biological Sciences, The University of Western Australia, Crawley, WA, Australia
| | - Tanya Solomon
- Experimental and Regenerative Neurosciences, School of Biological Sciences, The University of Western Australia, Crawley, WA, Australia
| | - Carole A Bartlett
- Experimental and Regenerative Neurosciences, School of Biological Sciences, The University of Western Australia, Crawley, WA, Australia
| | - Melinda Fitzgerald
- Experimental and Regenerative Neurosciences, School of Biological Sciences, The University of Western Australia, Crawley, WA, Australia.,Perron Institute for Neurological and Translational Science, Nedlands, WA, Australia.,Curtin Health Innovation Research Institute, Curtin University, Nedlands, WA, Australia
| | - Stuart I Hodgetts
- Experimental and Regenerative Neurosciences, School of Human Sciences, The University of Western Australia, Crawley, WA, Australia.,Perron Institute for Neurological and Translational Science, Nedlands, WA, Australia
| |
Collapse
|
17
|
Warnock A, Toomey LM, Wright AJ, Fisher K, Won Y, Anyaegbu C, Fitzgerald M. Damage Mechanisms to Oligodendrocytes and White Matter in Central Nervous System Injury: The Australian Context. J Neurotrauma 2020; 37:739-769. [DOI: 10.1089/neu.2019.6890] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Affiliation(s)
- Andrew Warnock
- Curtin Health Innovation Research Institute, Curtin University, Bentley, Western Australia, Australia
| | - Lillian M. Toomey
- Curtin Health Innovation Research Institute, Curtin University, Bentley, Western Australia, Australia
- Perron Institute for Neurological and Translational Science, Nedlands, Western Australia, Australia
| | - Alexander J. Wright
- Curtin Health Innovation Research Institute, Curtin University, Bentley, Western Australia, Australia
| | - Katherine Fisher
- School of Human Sciences, The University of Western Australia, Perth, Western Australia, Australia
| | - Yerim Won
- School of Human Sciences, The University of Western Australia, Perth, Western Australia, Australia
| | - Chidozie Anyaegbu
- Curtin Health Innovation Research Institute, Curtin University, Bentley, Western Australia, Australia
| | - Melinda Fitzgerald
- Curtin Health Innovation Research Institute, Curtin University, Bentley, Western Australia, Australia
- Perron Institute for Neurological and Translational Science, Nedlands, Western Australia, Australia
| |
Collapse
|
18
|
Guo L, Davis BM, Ravindran N, Galvao J, Kapoor N, Haamedi N, Shamsher E, Luong V, Fico E, Cordeiro MF. Topical recombinant human Nerve growth factor (rh-NGF) is neuroprotective to retinal ganglion cells by targeting secondary degeneration. Sci Rep 2020; 10:3375. [PMID: 32099056 PMCID: PMC7042238 DOI: 10.1038/s41598-020-60427-2] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2018] [Accepted: 01/16/2020] [Indexed: 12/13/2022] Open
Abstract
Optic neuropathy is a major cause of irreversible blindness worldwide, and no effective treatment is currently available. Secondary degeneration is believed to be the major contributor to retinal ganglion cell (RGC) death, the endpoint of optic neuropathy. Partial optic nerve transection (pONT) is an established model of optic neuropathy. Although the mechanisms of primary and secondary degeneration have been delineated in this model, until now how this is influenced by therapy is not well-understood. In this article, we describe a clinically translatable topical, neuroprotective treatment (recombinant human nerve growth factor, rh-NGF) predominantly targeting secondary degeneration in a pONT rat model. Topical application of rh-NGF twice daily for 3 weeks significantly improves RGC survival as shown by reduced RGC apoptosis in vivo and increased RGC population in the inferior retina, which is predominantly affected in this model by secondary degeneration. Topical rh-NGF also promotes greater axonal survival and inhibits astrocyte activity in the optic nerve. Collectively, these results suggest that topical rh-NGF exhibits neuroprotective effects on retinal neurons via influencing secondary degeneration process. As topical rh-NGF is already involved in early clinical trials, this highlights its potential in multiple indications in patients, including those affected by glaucomatous optic neuropathy.
Collapse
Affiliation(s)
- Li Guo
- Glaucoma & Retinal Neurodegeneration Research Group, Institute of Ophthalmology, University College London, London, United Kingdom.
| | - Benjamin M Davis
- Glaucoma & Retinal Neurodegeneration Research Group, Institute of Ophthalmology, University College London, London, United Kingdom
| | - Nivedita Ravindran
- Glaucoma & Retinal Neurodegeneration Research Group, Institute of Ophthalmology, University College London, London, United Kingdom
| | - Joana Galvao
- Glaucoma & Retinal Neurodegeneration Research Group, Institute of Ophthalmology, University College London, London, United Kingdom
| | - Neel Kapoor
- Glaucoma & Retinal Neurodegeneration Research Group, Institute of Ophthalmology, University College London, London, United Kingdom
| | - Nasrin Haamedi
- Glaucoma & Retinal Neurodegeneration Research Group, Institute of Ophthalmology, University College London, London, United Kingdom
| | - Ehtesham Shamsher
- Glaucoma & Retinal Neurodegeneration Research Group, Institute of Ophthalmology, University College London, London, United Kingdom
| | - Vy Luong
- Glaucoma & Retinal Neurodegeneration Research Group, Institute of Ophthalmology, University College London, London, United Kingdom
| | - Elena Fico
- Glaucoma & Retinal Neurodegeneration Research Group, Institute of Ophthalmology, University College London, London, United Kingdom.,Department of Biotechnological and Applied Clinical Sciences, University of L'Aquila, L'Aquila, Italy
| | - M Francesca Cordeiro
- Glaucoma & Retinal Neurodegeneration Research Group, Institute of Ophthalmology, University College London, London, United Kingdom. .,Western Eye Hospital, Imperial College Healthcare NHS Trust, London, United Kingdom.
| |
Collapse
|
19
|
Chiha W, Bartlett CA, Petratos S, Fitzgerald M, Harvey AR. Intravitreal application of AAV-BDNF or mutant AAV-CRMP2 protects retinal ganglion cells and stabilizes axons and myelin after partial optic nerve injury. Exp Neurol 2020; 326:113167. [PMID: 31904385 DOI: 10.1016/j.expneurol.2019.113167] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2019] [Revised: 12/20/2019] [Accepted: 12/31/2019] [Indexed: 12/29/2022]
Abstract
Secondary degeneration following an initial injury to the central nervous system (CNS) results in increased tissue loss and is associated with increasing functional impairment. Unilateral partial dorsal transection of the adult rat optic nerve (ON) has proved to be a useful experimental model in which to study factors that contribute to secondary degenerative events. Using this injury model, we here quantified the protective effects of intravitreally administered bi-cistronic adeno-associated viral (AAV2) vectors encoding either brain derived neurotrophic factor (BDNF) or a mutant, phospho-resistant, version of collapsin response mediator protein 2 (CRMP2T555A) on retinal ganglion cells (RGCs), their axons, and associated myelin. To test for potential synergistic interactions, some animals received combined injections of both vectors. Three months post-injury, all treatments maintained RGC numbers in central retina, but only AAV2-BDNF significantly protected ventrally located RGCs exclusively vulnerable to secondary degeneration. Behaviourally, treatments that involved AAV2-BDNF significantly restored the number of smooth-pursuit phases of optokinetic nystagmus. While all therapeutic regimens preserved axonal density and proportions of typical complexes, including heminodes and single nodes, BDNF treatments were generally more effective in maintaining the length of the node of Ranvier in myelin surrounding ventral ON axons after injury. Both AAV2-BDNF and AAV2-CRMP2T555A prevented injury-induced changes in G-ratio and overall myelin thickness, but only AAV2-BDNF administration protected against large-scale myelin decompaction in ventral ON. In summary, in a model of secondary CNS degeneration, both BDNF and CRMP2T555A vectors were neuroprotective, however different efficacies were observed for these overexpressed proteins in the retina and ON, suggesting disparate cellular and molecular targets driving responses for neural repair. The potential use of these vectors to treat other CNS injuries and pathologies is discussed.
Collapse
Affiliation(s)
- Wissam Chiha
- School of Biological Sciences, The University of Western Australia, WA 6009, Australia; Curtin Health Innovation Research Institute, Curtin University, Belmont, WA 6102, Australia
| | - Carole A Bartlett
- School of Biological Sciences, The University of Western Australia, WA 6009, Australia
| | - Steven Petratos
- Department of Neuroscience, Monash University, VIC 3004, Australia
| | - Melinda Fitzgerald
- Perron Institute for Neurological and Translational Science, Nedlands, WA 6009, Australia; Curtin Health Innovation Research Institute, Curtin University, Belmont, WA 6102, Australia
| | - Alan R Harvey
- School of Human Sciences, The University of Western Australia, WA 6009, Australia; Perron Institute for Neurological and Translational Science, Nedlands, WA 6009, Australia.
| |
Collapse
|
20
|
Naidu PSR, Denham E, Bartlett CA, McGonigle T, Taylor NL, Norret M, Smith NM, Dunlop SA, Iyer KS, Fitzgerald M. Protein corona formation moderates the release kinetics of ion channel antagonists from transferrin-functionalized polymeric nanoparticles. RSC Adv 2020; 10:2856-2869. [PMID: 35496130 PMCID: PMC9048831 DOI: 10.1039/c9ra09523c] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2019] [Accepted: 12/25/2019] [Indexed: 11/21/2022] Open
Abstract
Transferrin (Tf)-functionalized p(HEMA-ran-GMA) nanoparticles were designed to incorporate and release a water-soluble combination of three ion channel antagonists, namely zonampanel monohydrate (YM872), oxidized adenosine triphosphate (oxATP) and lomerizine hydrochloride (LOM) identified as a promising therapy for secondary degeneration that follows neurotrauma. Coupled with a mean hydrodynamic size of 285 nm and near-neutral surface charge of −5.98 mV, the hydrophilic nature of the functionalized polymeric nanoparticles was pivotal in effectively encapsulating the highly water soluble YM872 and oxATP, as well as lipophilic LOM dissolved in water-based medium, by a back-filling method. Maximum loading efficiencies of 11.8 ± 1.05% (w/w), 13.9 ± 1.50% (w/w) and 22.7 ± 4.00% (w/w) LOM, YM872 and oxATP respectively were reported. To obtain an estimate of drug exposure in vivo, drug release kinetics assessment by HPLC was conducted in representative physiological milieu containing 55% (v/v) human serum at 37 °C. In comparison to serum-free conditions, it was demonstrated that the inevitable adsorption of serum proteins on the Tf-functionalized nanoparticle surface as a protein corona impeded the rate of release of LOM and YM872 at both pH 5 and 7.4 over a period of 1 hour. While the release of oxATP from the nanoparticles was detectable for up to 30 minutes under serum-free conditions at pH 7.4, the presence of serum proteins and a slightly acidic environment impaired the detection of the drug, possibly due to its molecular instability. Nevertheless, under representative physiological conditions, all three drugs were released in combination from Tf-functionalized p(HEMA-ran-GMA) nanoparticles and detected for up to 20 minutes. Taken together, the study provided enhanced insight into potential physiological outcomes in the presence of serum proteins, and suggests that p(HEMA-ran-GMA)-based therapeutic nanoparticles may be promising drug delivery vehicles for CNS therapy. Transferrin (Tf)-functionalized p(HEMA-ran-GMA) nanoparticles were designed to incorporate and release a water-soluble combination of three ion channel antagonists, identified as a promising therapy for secondary degeneration following neurotrauma.![]()
Collapse
Affiliation(s)
- Priya S. R. Naidu
- School of Molecular Sciences
- The University of Western Australia
- Crawley
- Australia
| | - Eleanor Denham
- Curtin Health Innovation Research Institute
- Curtin University
- Bentley
- Australia
| | - Carole A. Bartlett
- Curtin Health Innovation Research Institute
- Curtin University
- Bentley
- Australia
| | - Terry McGonigle
- Curtin Health Innovation Research Institute
- Curtin University
- Bentley
- Australia
| | - Nicolas L. Taylor
- School of Molecular Sciences
- The University of Western Australia
- Crawley
- Australia
- Australian Research Council Centre of Excellence in Plant Energy Biology
| | - Marck Norret
- School of Molecular Sciences
- The University of Western Australia
- Crawley
- Australia
| | - Nicole. M. Smith
- School of Molecular Sciences
- The University of Western Australia
- Crawley
- Australia
| | - Sarah A. Dunlop
- School of Biological Sciences
- The University of Western Australia
- Crawley
- Australia
| | - K. Swaminathan Iyer
- School of Molecular Sciences
- The University of Western Australia
- Crawley
- Australia
| | - Melinda Fitzgerald
- Curtin Health Innovation Research Institute
- Curtin University
- Bentley
- Australia
- School of Biological Sciences
| |
Collapse
|
21
|
Reichenbach A, Bringmann A. Glia of the human retina. Glia 2019; 68:768-796. [PMID: 31793693 DOI: 10.1002/glia.23727] [Citation(s) in RCA: 156] [Impact Index Per Article: 31.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2019] [Revised: 07/16/2019] [Accepted: 07/17/2019] [Indexed: 12/22/2022]
Abstract
The human retina contains three types of glial cells: microglia and two types of macroglia, astrocytes and Müller cells. Macroglia provide homeostatic and metabolic support to photoreceptors and neurons required for neuronal activity. The fovea, the site of the sharpest vision which is astrocyte- and microglia-free, contains two populations of Müller glia: cells which form the Müller cell cone in the foveola and z-shaped Müller cells of the foveal walls. Both populations are characterized by morphological and functional differences. Müller cells of the foveola do not support the activity of photoreceptors and neurons, but provide the structural stability of the foveal tissue and improve the light transmission through the tissue to the photoreceptors. This article gives overviews of the glia of the human retina and the structure and function of both Müller cell types in the fovea, and describes the contributions of astrocytes and Müller cells to the ontogenetic development of the fovea.
Collapse
Affiliation(s)
- Andreas Reichenbach
- Paul Flechsig Institute of Brain Research, University of Leipzig, Leipzig, Germany
| | - Andreas Bringmann
- Department of Ophthalmology and Eye Hospital, University of Leipzig, Leipzig, Germany
| |
Collapse
|
22
|
Toomey LM, Bartlett CA, Gavriel N, McGonigle T, Majimbi M, Gopalasingam G, Rodger J, Fitzgerald M. Comparing modes of delivery of a combination of ion channel inhibitors for limiting secondary degeneration following partial optic nerve transection. Sci Rep 2019; 9:15297. [PMID: 31653948 PMCID: PMC6814709 DOI: 10.1038/s41598-019-51886-3] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2019] [Accepted: 10/07/2019] [Indexed: 11/28/2022] Open
Abstract
Injury to the central nervous system is exacerbated by secondary degeneration. Previous research has shown that a combination of orally and locally administered ion channel inhibitors following partial optic nerve injury protects the myelin sheath and preserves function in the ventral optic nerve, vulnerable to secondary degeneration. However, local administration is often not clinically appropriate. This study aimed to compare the efficacy of systemic and local delivery of the ion channel inhibitor combination of lomerizine, brilliant blue G (BBG) and YM872, which inhibits voltage-gated calcium channels, P2X7 receptors and Ca2+ permeable α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA) receptors respectively. Following a partial optic nerve transection, adult female PVG rats were treated with BBG and YM872 delivered via osmotic mini pump directly to the injury site, or via intraperitoneal injection, both alongside oral administration of lomerizine. Myelin structure was preserved with both delivery modes of the ion channel inhibitor combination. However, there was no effect of treatment on inflammation, either peripherally or at the injury site, or on the density of oligodendroglial cells. Taken together, the data indicate that even at lower concentrations, the combinatorial treatment may be preserving myelin structure, and that systemic and local delivery are comparable at improving outcomes following neurotrauma.
Collapse
Affiliation(s)
- Lillian M Toomey
- Experimental and Regenerative Neurosciences, School of Biological Sciences, The University of Western Australia, 35 Stirling Hwy, Perth, 6009, Western Australia, Australia
- Curtin Health Innovation Research Institute, Curtin University, Sarich Neuroscience Research Institute Building, 8 Verdun St, Nedlands, 6009, Western Australia, Australia
- Perron Institute for Neurological and Translational Science, Sarich Neuroscience Research Institute Building, 8 Verdun St, Nedlands, 6009, Western Australia, Australia
| | - Carole A Bartlett
- Experimental and Regenerative Neurosciences, School of Biological Sciences, The University of Western Australia, 35 Stirling Hwy, Perth, 6009, Western Australia, Australia
| | - Nikolas Gavriel
- Experimental and Regenerative Neurosciences, School of Biological Sciences, The University of Western Australia, 35 Stirling Hwy, Perth, 6009, Western Australia, Australia
| | - Terence McGonigle
- Curtin Health Innovation Research Institute, Curtin University, Sarich Neuroscience Research Institute Building, 8 Verdun St, Nedlands, 6009, Western Australia, Australia
| | - Maimuna Majimbi
- Curtin Health Innovation Research Institute, Curtin University, Sarich Neuroscience Research Institute Building, 8 Verdun St, Nedlands, 6009, Western Australia, Australia
| | - Gopana Gopalasingam
- Experimental and Regenerative Neurosciences, School of Biological Sciences, The University of Western Australia, 35 Stirling Hwy, Perth, 6009, Western Australia, Australia
| | - Jennifer Rodger
- Experimental and Regenerative Neurosciences, School of Biological Sciences, The University of Western Australia, 35 Stirling Hwy, Perth, 6009, Western Australia, Australia
- Perron Institute for Neurological and Translational Science, Sarich Neuroscience Research Institute Building, 8 Verdun St, Nedlands, 6009, Western Australia, Australia
| | - Melinda Fitzgerald
- Experimental and Regenerative Neurosciences, School of Biological Sciences, The University of Western Australia, 35 Stirling Hwy, Perth, 6009, Western Australia, Australia.
- Curtin Health Innovation Research Institute, Curtin University, Sarich Neuroscience Research Institute Building, 8 Verdun St, Nedlands, 6009, Western Australia, Australia.
- Perron Institute for Neurological and Translational Science, Sarich Neuroscience Research Institute Building, 8 Verdun St, Nedlands, 6009, Western Australia, Australia.
| |
Collapse
|
23
|
Andries L, De Groef L, Moons L. Neuroinflammation and Optic Nerve Regeneration: Where Do We Stand in Elucidating Underlying Cellular and Molecular Players? Curr Eye Res 2019; 45:397-409. [PMID: 31567007 DOI: 10.1080/02713683.2019.1669664] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
Neurodegenerative diseases and central nervous system (CNS) trauma are highly irreversible, in part because adult mammals lack a robust regenerative capacity. A multifactorial problem underlies the limited axonal regeneration potential. Strikingly, neuroinflammation seems able to induce axonal regrowth in the adult mammalian CNS. It is increasingly clear that both blood-borne and resident inflammatory cells as well as reactivated glial cells affect axonal regeneration. The scope of this review is to give a comprehensive overview of the knowledge that links inflammation (with a focus on the innate immune system) to axonal regeneration and to critically reflect on the controversy that still prevails about the cells, molecules and pathways that are dominating the scene. Also, a brief overview is given of what is already known about the crosstalk between and the heterogeneity of cell types that might play a role in axonal regeneration. Recent research indicates that inflammation-induced axonal regrowth is not solely driven by a single-cell population but probably relies on the crosstalk between multiple cell types and the strong regulation of these cell populations in time and space. Moreover, there is growing evidence that the different cell populations are highly heterogeneous and as such can react differently upon injury. This could explain the controversial results that have been obtained over the past years. The primary focus of this manuscript is the retinofugal system of adult mammals, however, when relevant, insights or examples of the spontaneous regenerating zebrafish model and spinal cord research are added.
Collapse
Affiliation(s)
- Lien Andries
- Department of Biology, Neural Circuit Development and Regeneration Research Group, KU Leuven, Leuven, Belgium
| | - Lies De Groef
- Department of Biology, Neural Circuit Development and Regeneration Research Group, KU Leuven, Leuven, Belgium
| | - Lieve Moons
- Department of Biology, Neural Circuit Development and Regeneration Research Group, KU Leuven, Leuven, Belgium
| |
Collapse
|
24
|
Lam C, Li KK, Do CW, Chan H, To CH, Kwong JMK. Quantitative profiling of regional protein expression in rat retina after partial optic nerve transection using fluorescence difference two‑dimensional gel electrophoresis. Mol Med Rep 2019; 20:2734-2742. [PMID: 31524249 PMCID: PMC6691257 DOI: 10.3892/mmr.2019.10525] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2019] [Accepted: 05/14/2019] [Indexed: 12/17/2022] Open
Abstract
To examine the difference between primary and secondary retinal ganglion cell (RGC) degeneration, the protein expression at four regions of retina including superior, temporal, inferior and nasal quadrant in a rat model of partial optic nerve transection (pONT) using 2-D Fluorescence Difference Gel Electrophoresis (DIGE) were investigated. Unilateral pONT was performed on the temporal side of optic nerves of adult Wistar rats to separate primary and secondary RGC loss. Topographical quantification of RGCs labeled by Rbpms antibody and analysis of axonal injury by grading of optic nerve damage at 1 week (n=8) and 8 weeks (n=15) after pONT demonstrated early RGC loss at temporal region, which is considered as primary RGC degeneration and progressing RGC loss at nasal region, which is considered as secondary RGC degeneration. Early protein expression in each retinal quadrant (n=4) at 2 weeks after pONT was compared with the corresponding quadrant in the contralateral control eye by DIGE. For all comparisons, 24 differentially expressed proteins (>1.2-fold; P<0.05; ≥3 non-duplicated peptide matches) were identified by mass spectrometry (MS). Interestingly, in the nasal retina, serum albumin and members of crystallin family, including αA, αB, βA2, βA3, βB2 and γS indicating stress response were upregulated. By contrast, only αB and βA2 crystallin proteins were altered in temporal quadrant. In the superior and inferior quadrants, βB2 crystallin, keratin type I, S-arrestin and lamin-B1 were upregulated, while heat shock cognate 71 kDa protein and heterogeneous nuclear ribonucleoproteins A2/B1 were downregulated. In summary, the use of DIGE followed by MS is useful to detect early regional protein regulation in the retina after localized optic nerve injury.
Collapse
Affiliation(s)
- Chuen Lam
- School of Optometry, Hong Kong Polytechnic University, Hong Kong 999077, SAR, P.R. China
| | - King Kit Li
- School of Optometry, Hong Kong Polytechnic University, Hong Kong 999077, SAR, P.R. China
| | - Chi Wai Do
- School of Optometry, Hong Kong Polytechnic University, Hong Kong 999077, SAR, P.R. China
| | - Henry Chan
- School of Optometry, Hong Kong Polytechnic University, Hong Kong 999077, SAR, P.R. China
| | - Chi Ho To
- School of Optometry, Hong Kong Polytechnic University, Hong Kong 999077, SAR, P.R. China
| | - Jacky Man Kwong Kwong
- Department of Ophthalmology, Stein Eye Institute, David Geffen School of Medicine, University of California Los Angeles, Los Angeles, CA 90095, USA
| |
Collapse
|
25
|
Gopalasingam G, Bartlett CA, McGonigle T, Majimbi M, Warnock A, Ford A, Gough A, Toomey LM, Fitzgerald M. The effects of a combination of ion channel inhibitors on pathology in a model of demyelinating disease. Mult Scler Relat Disord 2019; 34:1-8. [PMID: 31202958 DOI: 10.1016/j.msard.2019.06.005] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2018] [Revised: 05/16/2019] [Accepted: 06/07/2019] [Indexed: 12/22/2022]
Abstract
BACKGROUND Multiple sclerosis (MS) has been shown to feature oxidative damage, which can be modelled using the cuprizone model of demyelinating disease. Oxidative damage can occur as a result of excessive influx of calcium ions (Ca2+) and oligodendroglia are particularly vulnerable. However, the effects of limiting excess Ca2+ influx on oxidative damage, oligodendroglia and myelin structure are unknown. OBJECTIVE This study investigated the effects of limiting excess Ca2+ flux on oxidative damage and associated changes in oligodendroglial densities and Node of Ranvier structure in the cuprizone model. METHODS The effects of three weeks of cuprizone administration and of treatment with a combination of three ion channel inhibitors (Lomerizine, Brilliant Blue G (BBG) and YM872), were semi-quantified immunohistochemically. Outcomes assessed were protein nitration (3-nitrotyrosine (3NT)) oxidative damage to DNA (8-hydroxy deoxyguanosine (8OHDG)), advanced glycation end-products (carboxymethyl lysine (CML)), immunoreactivity of microglia (Iba1) and astrocytes (glial acidic fibrillary protein (GFAP)), densities of oligodendrocyte precursor cells (OPCs) (platelet derived growth factor alpha receptor (PDGFαR) with olig2) and oligodendrocytes (olig2 and CC1), and structural elements of the Node of Ranvier (contactin associated protein (Caspr)). RESULTS The administration of cuprizone resulted in increased protein nitration, DNA damage, and astrocyte and microglial immunoreactivity, a decrease in the density of oligodendrocytes and OPCs, together with altered structure of the Node of Ranvier and reduced myelin basic protein immunoreactivity. Treatment with the ion channel inhibitor combination significantly lowered protein nitration, increased the density of OPCs and reduced the number of atypical Node of Ranvier complexes; other outcomes were unaffected. CONCLUSION Our findings suggest that excess Ca2+ influx contributes to protein nitration, and associated changes to OPC densities and Node of Ranvier structure in demyelinating disease.
Collapse
Affiliation(s)
- Gopana Gopalasingam
- Experimental and Regenerative Neurosciences, School of Biological Sciences, The University of Western Australia, 35 Stirling Hwy, Nedlands, Western Australia 6009, Australia; School of Human Sciences, The University of Western Australia, 35 Stirling Hwy, Nedlands, Western Australia 6009, Australia
| | - Carole A Bartlett
- Experimental and Regenerative Neurosciences, School of Biological Sciences, The University of Western Australia, 35 Stirling Hwy, Nedlands, Western Australia 6009, Australia
| | - Terence McGonigle
- Curtin Health Innovation Research Institute, Curtin University, Belmont, Western Australia, Australia
| | - Maimuna Majimbi
- Curtin Health Innovation Research Institute, Curtin University, Belmont, Western Australia, Australia
| | - Andrew Warnock
- Curtin Health Innovation Research Institute, Curtin University, Belmont, Western Australia, Australia
| | - Abbey Ford
- Experimental and Regenerative Neurosciences, School of Biological Sciences, The University of Western Australia, 35 Stirling Hwy, Nedlands, Western Australia 6009, Australia
| | - Alexander Gough
- Experimental and Regenerative Neurosciences, School of Biological Sciences, The University of Western Australia, 35 Stirling Hwy, Nedlands, Western Australia 6009, Australia
| | - Lillian M Toomey
- Curtin Health Innovation Research Institute, Curtin University, Belmont, Western Australia, Australia; Perron Institute for Neurological and Translational Science, Sarich Neuroscience Research Institute Building, 8 Verdun St, Nedlands, Western Australia 6009, Australia
| | - Melinda Fitzgerald
- Experimental and Regenerative Neurosciences, School of Biological Sciences, The University of Western Australia, 35 Stirling Hwy, Nedlands, Western Australia 6009, Australia; Curtin Health Innovation Research Institute, Curtin University, Belmont, Western Australia, Australia; Perron Institute for Neurological and Translational Science, Sarich Neuroscience Research Institute Building, 8 Verdun St, Nedlands, Western Australia 6009, Australia.
| |
Collapse
|
26
|
|
27
|
Li HY, Huang M, Luo QY, Hong X, Ramakrishna S, So KF. Lycium barbarum (Wolfberry) Increases Retinal Ganglion Cell Survival and Affects both Microglia/Macrophage Polarization and Autophagy after Rat Partial Optic Nerve Transection. Cell Transplant 2019; 28:607-618. [PMID: 30838886 PMCID: PMC7103598 DOI: 10.1177/0963689719835181] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
The rat partial optic nerve transection (PONT) model has been used for studying secondary
degeneration of retinal ganglion cells (RGCs) in recent years. In this study, we carried
out PONT of the temporal side of rat optic nerves, whereas PONT was carried out of the
superior side in the previous publication. We found that this surgery is better and easier
than the previous method and can produce a repeatable and reliable model. We detected
significant changes in the polarization of microglia/macrophages and the level of
autophagy in optic nerves after PONT. We also used this model to detect the effects of the
polysaccharides extracted from Lycium barbarum (LBP) on the survival of
RGCs and the changes in the polarization of microglia/macrophages and the level of
autophagy after PONT. We find that LBP can delay secondary degeneration of RGCs after
temporal injury of optic nerves, promote the M2 polarization of microglia/macrophages, and
down-regulate the level of autophagy after PONT. In conclusion, we find that the
polarization of microglia/macrophages and the autophagy level change after PONT; LBP
treatment delays secondary degeneration of RGCs; and the polarization of
microglia/macrophages and the level of autophagy are also altered after LBP treatment.
Collapse
Affiliation(s)
- Hong-Ying Li
- 1 Department of Anatomy, Medical School, Jinan University, Guangzhou, China.,2 Collaborative Joint Laboratory, Guangdong-Hongkong-Macau Institute of CNS Regeneration, Ministry of Education CNS Regeneration, Jinan University, Guangzhou, China.,3 Guangzhou Regenerative Medicine and Health Guangdong Laboratory, Guangzhou, China
| | - Mi Huang
- 2 Collaborative Joint Laboratory, Guangdong-Hongkong-Macau Institute of CNS Regeneration, Ministry of Education CNS Regeneration, Jinan University, Guangzhou, China.,3 Guangzhou Regenerative Medicine and Health Guangdong Laboratory, Guangzhou, China
| | - Qiu-Yan Luo
- 1 Department of Anatomy, Medical School, Jinan University, Guangzhou, China
| | - Xi Hong
- 1 Department of Anatomy, Medical School, Jinan University, Guangzhou, China.,2 Collaborative Joint Laboratory, Guangdong-Hongkong-Macau Institute of CNS Regeneration, Ministry of Education CNS Regeneration, Jinan University, Guangzhou, China.,3 Guangzhou Regenerative Medicine and Health Guangdong Laboratory, Guangzhou, China
| | - Seeram Ramakrishna
- 2 Collaborative Joint Laboratory, Guangdong-Hongkong-Macau Institute of CNS Regeneration, Ministry of Education CNS Regeneration, Jinan University, Guangzhou, China
| | - Kwok-Fai So
- 2 Collaborative Joint Laboratory, Guangdong-Hongkong-Macau Institute of CNS Regeneration, Ministry of Education CNS Regeneration, Jinan University, Guangzhou, China.,3 Guangzhou Regenerative Medicine and Health Guangdong Laboratory, Guangzhou, China.,4 Guangdong Key Laboratory of Brain Function and Diseases, Jinan University, Guangzhou, China.,5 State Key Laboratory of Brain and Cognitive Sciences and Department of Ophthalmology, The University of Hong Kong, Hong Kong, China
| |
Collapse
|
28
|
Li HY, Hong X, Huang M, So KF. Voluntary running delays primary degeneration in rat retinas after partial optic nerve transection. Neural Regen Res 2019; 14:728-734. [PMID: 30632515 PMCID: PMC6352605 DOI: 10.4103/1673-5374.247481] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
Running is believed to be beneficial for human health. Many studies have focused on the neuroprotective effects of voluntary running on animal models. There were both primary and secondary degeneration in neurodegenerative diseases, including glaucoma. However, whether running can delay primary or secondary degeneration or both of them was not clear. Partial optic nerve transection model is a valuable glaucoma model for studying both primary and secondary degeneration because it can separate primary (mainly in the superior retina) from secondary (mainly in the inferior retina) degeneration. Therefore, we compared the survival of retinal ganglion cells between Sprague-Dawley rat runners and non-runners both in the superior and inferior retinas. Excitotoxicity, oxidative stress, and apoptosis are involved in the degeneration of retinal ganglion cells in glaucoma. So we also used western immunoblotting to compare the expression of some proteins involved in apoptosis (phospho-c-Jun N-terminal kinases, p-JNKs), oxidative stress (manganese superoxide dismutase, MnSOD) and excitotoxicity (glutamine synthetase) between runners and non-runners after partial optic nerve transection. Results showed that voluntary running delayed the death of retinal ganglion cells vulnerable to primary degeneration but not those to secondary degeneration. In addition, voluntary running decreased the expression of glutamine synthetase, but not the expression of p-JNKs and MnSOD in the superior retina after partial optic nerve transection. These results illustrated that primary degeneration of retinal ganglion cells might be mainly related with excitotoxicity rather than oxidative stress; and the voluntary running could down-regulate excitotoxicity to delay the primary degeneration of retinal ganglion cells after partial optic nerve transection.
Collapse
Affiliation(s)
- Hong-Ying Li
- Department of Anatomy, School of Medicine; Guangdong-Hongkong-Macau Institute of CNS Regeneration, Ministry of Education CNS Regeneration Collaborative Joint Laboratory, Jinan University, Guangzhou, Guangdong Province, China
| | - Xi Hong
- Department of Anatomy, School of Medicine, Jinan University, Guangzhou, Guangdong Province, China
| | - Mi Huang
- Guangdong-Hongkong-Macau Institute of CNS Regeneration, Ministry of Education CNS Regeneration Collaborative Joint Laboratory; Guangdong Key Laboratory of Brain Function and Diseases, Jinan University, Guangzhou, Guangdong Province, China
| | - Kwok-Fai So
- Guangdong-Hongkong-Macau Institute of CNS Regeneration, Ministry of Education CNS Regeneration Collaborative Joint Laboratory; Guangdong Key Laboratory of Brain Function and Diseases, Jinan University, Guangzhou, Guangdong Province; Department of Ophthalmology and State Key Laboratory of Brain and Cognitive Sciences, The University of Hong Kong, Hong Kong Special Administrative Region, China
| |
Collapse
|
29
|
Giacci M, Fitzgerald M. Oligodendroglia Are Particularly Vulnerable to Oxidative Damage After Neurotrauma In Vivo. J Exp Neurosci 2018; 12:1179069518810004. [PMID: 30479489 PMCID: PMC6240964 DOI: 10.1177/1179069518810004] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2018] [Accepted: 10/09/2018] [Indexed: 11/15/2022] Open
Abstract
In the paper “Oligodendroglia are particularly vulnerable to oxidative damage after neurotrauma in vivo,” we determined the extent of oxidative damage to specific cellular subpopulations and structures within regions vulnerable to secondary degeneration and assessed the effect this had on oligodendroglial function. Comparative assessment of oxidative damage demonstrated selective vulnerability of oligodendroglia, specifically oligodendrocyte progenitor cells (OPCs) to DNA oxidation in vivo. Immunohistochemical fate mapping along the oligodendroglial lineage showed a transient susceptibility of these cells to DNA oxidation, protein nitration, and lipid peroxidation, with mature oligodendrocytes derived immediately after injury more vulnerable to DNA oxidation than their counterparts existing at the time of injury or later derived. In situ hybridization demonstrated a reduction in myelin regulatory factor (MyRF) messenger RNA (mRNA) fluorescence in newly derived mature oligodendrocytes, suggesting a compromise in the production and maintenance of the myelin sheath in these cells. The data imply a deficit in the normal differentiation of OPCs to myelinating oligodendrocytes, associated with a transient increase in oxidative damage, which may contribute to the dysmyelinating phenotype seen at chronic time points after injury. Identifying and understanding the sources of this oxidative damage is integral for the development of therapeutic interventions for neurotrauma.
Collapse
Affiliation(s)
- Marcus Giacci
- School of Biological Sciences, The University of Western Australia, Nedlands, Australia
| | - Melinda Fitzgerald
- School of Biological Sciences, The University of Western Australia, Nedlands, Australia.,Curtin Health Innovation Research Institute, Curtin University, Belmont, Australia.,Perron Institute for Neurological and Translational Sciences, Sarich Neuroscience Research Institute Building, Nedlands, Australia
| |
Collapse
|
30
|
The Effects of a Combination of Ion Channel Inhibitors in Female Rats Following Repeated Mild Traumatic Brain Injury. Int J Mol Sci 2018; 19:ijms19113408. [PMID: 30384417 PMCID: PMC6274967 DOI: 10.3390/ijms19113408] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2018] [Revised: 10/26/2018] [Accepted: 10/27/2018] [Indexed: 01/26/2023] Open
Abstract
Following mild traumatic brain injury (mTBI), the ionic homeostasis of the central nervous system (CNS) becomes imbalanced. Excess Ca2+ influx into cells triggers molecular cascades, which result in detrimental effects. The authors assessed the effects of a combination of ion channel inhibitors (ICI) following repeated mTBI (rmTBI). Adult female rats were subjected to two rmTBI weight-drop injuries 24 h apart, sham procedures (sham), or no procedures (normal). Lomerizine, which inhibits voltage-gated calcium channels, was administered orally twice daily, whereas YM872 and Brilliant Blue G, inhibiting α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA) and P2X₇ receptors, respectively, were delivered intraperitoneally every 48 h post-injury. Vehicle treatment controls were included for rmTBI, sham, and normal groups. At 11 days following rmTBI, there was a significant increase in the time taken to cross the 3 cm beam, as a sub-analysis of neurological severity score (NSS) assessments, compared with the normal control (p < 0.05), and a significant decrease in learning-associated improvement in rmTBI in Morris water maze (MWM) trials relative to the sham (p < 0.05). ICI-treated rmTBI animals were not different to sham, normal controls, or rmTBI treated with vehicle in all neurological severity score and Morris water maze assessments (p > 0.05). rmTBI resulted in increases in microglial cell density, antioxidant responses (manganese-dependent superoxide dismutase (MnSOD) immunoreactivity), and alterations to node of Ranvier structure. ICI treatment decreased microglial density, MnSOD immunoreactivity, and abnormalities of the node of Ranvier compared with vehicle controls (p < 0.01). The authors' findings demonstrate the beneficial effects of the combinatorial ICI treatment on day 11 post-rmTBI, suggesting an attractive therapeutic strategy against the damage induced by excess Ca2+ following rmTBI.
Collapse
|
31
|
Comparison of ion channel inhibitor combinations for limiting secondary degeneration following partial optic nerve transection. Exp Brain Res 2018; 237:161-171. [DOI: 10.1007/s00221-018-5414-0] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2018] [Accepted: 10/21/2018] [Indexed: 11/25/2022]
|
32
|
Smith NM, Giacci MK, Gough A, Bailey C, McGonigle T, Black AMB, Clarke TO, Bartlett CA, Swaminathan Iyer K, Dunlop SA, Fitzgerald M. Inflammation and blood-brain barrier breach remote from the primary injury following neurotrauma. J Neuroinflammation 2018; 15:201. [PMID: 29981582 PMCID: PMC6035802 DOI: 10.1186/s12974-018-1227-0] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2018] [Accepted: 06/15/2018] [Indexed: 01/09/2023] Open
Abstract
BACKGROUND Following injury to the central nervous system, increased microglia, secretion of pro- and anti-inflammatory cytokines, and altered blood-brain barrier permeability, a hallmark of degeneration, are observed at and immediately adjacent to the injury site. However, few studies investigate how regions remote from the primary injury could also suffer from inflammation and secondary degeneration. METHODS Adult female Piebald-Viral-Glaxo (PVG) rats underwent partial transection of the right optic nerve, with normal, age-matched, unoperated animals as controls. Perfusion-fixed brains and right optic nerves were harvested for immunohistochemical assessment of inflammatory markers and blood-brain barrier integrity; fresh-frozen brains were used for multiplex cytokine analysis. RESULTS Immediately ventral to the optic nerve injury, immunointensity of both the pro-inflammatory biomarker inducible nitric oxide synthase (iNOS) and the anti-inflammatory biomarker arginase-1 (Arg1) increased at 7 days post-injury, with colocalization of iNOS and Arg1 immunoreactivity within individual cells. CD11b+ and CD45+ cells were increased 7 days post-injury, with altered BBB permeability still evident at this time. In the lower and middle optic tract and superior colliculus, IBA1+ resident microglia were first increased at 3 days; ED1+ and CD11b+ cells were first increased in the middle and upper tract and superior colliculus 7 days post-injury. Increased fibrinogen immunoreactivity indicative of altered BBB permeability was first observed in the contralateral upper tract at 3 days and middle tract at 7 days post-injury. Multiplex cytokine analysis of brain homogenates indicated significant increases in the pro-inflammatory cytokines, IL-2 and TNFα, and anti-inflammatory cytokine IL-10 1 day post-injury, decreasing to control levels at 3 days for TNFα and 7 days for IL-2. IL-10 was significantly elevated at 1 and 7 days post-injury with a dip at 3 days post-injury. CONCLUSIONS Partial injury to the optic nerve induces a complex remote inflammatory response, characterized by rapidly increased pro- and anti-inflammatory cytokines in brain homogenates, increased numbers of IBA1+ cells throughout the visual pathways, and increased CD11b+ and ED1+ inflammatory cells, particularly towards the synaptic terminals. BBB permeability can increase prior to inflammatory cell infiltration, dependent on the brain region.
Collapse
Affiliation(s)
- Nicole M Smith
- School of Molecular Sciences, The University of Western Australia, Stirling Hwy, Perth, Western Australia, 6009, Australia
| | - Marcus K Giacci
- Experimental and Regenerative Neurosciences, School of Biological Sciences, The University of Western Australia, Stirling Hwy, Perth, Western Australia, 6009, Australia
| | - Alexander Gough
- Experimental and Regenerative Neurosciences, School of Biological Sciences, The University of Western Australia, Stirling Hwy, Perth, Western Australia, 6009, Australia
| | - Charlotte Bailey
- School of Molecular Sciences, The University of Western Australia, Stirling Hwy, Perth, Western Australia, 6009, Australia
| | - Terence McGonigle
- Curtin Health Innovation Research Institute, Curtin University, Verdun St, Nedlands, Western Australia, Australia
| | - Anna M B Black
- Curtin Health Innovation Research Institute, Curtin University, Verdun St, Nedlands, Western Australia, Australia
| | - Thomas O Clarke
- Curtin Health Innovation Research Institute, Curtin University, Verdun St, Nedlands, Western Australia, Australia
| | - Carole A Bartlett
- Experimental and Regenerative Neurosciences, School of Biological Sciences, The University of Western Australia, Stirling Hwy, Perth, Western Australia, 6009, Australia.,Curtin Health Innovation Research Institute, Curtin University, Verdun St, Nedlands, Western Australia, Australia
| | - K Swaminathan Iyer
- School of Molecular Sciences, The University of Western Australia, Stirling Hwy, Perth, Western Australia, 6009, Australia
| | - Sarah A Dunlop
- Experimental and Regenerative Neurosciences, School of Biological Sciences, The University of Western Australia, Stirling Hwy, Perth, Western Australia, 6009, Australia
| | - Melinda Fitzgerald
- Experimental and Regenerative Neurosciences, School of Biological Sciences, The University of Western Australia, Stirling Hwy, Perth, Western Australia, 6009, Australia. .,Curtin Health Innovation Research Institute, Curtin University, Verdun St, Nedlands, Western Australia, Australia. .,Perron Institute for Neurological and Translational Science, Sarich Neuroscience Research Institute, Verdun St, Nedlands, Western Australia, 6009, Australia.
| |
Collapse
|
33
|
Oligodendroglia Are Particularly Vulnerable to Oxidative Damage after Neurotrauma In Vivo. J Neurosci 2018; 38:6491-6504. [PMID: 29915135 DOI: 10.1523/jneurosci.1898-17.2018] [Citation(s) in RCA: 59] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2017] [Revised: 05/13/2018] [Accepted: 05/16/2018] [Indexed: 01/13/2023] Open
Abstract
Loss of function following injury to the CNS is worsened by secondary degeneration of neurons and glia surrounding the injury and is initiated by oxidative damage. However, it is not yet known which cellular populations and structures are most vulnerable to oxidative damage in vivo Using Nanoscale secondary ion mass spectrometry (NanoSIMS), oxidative damage was semiquantified within cellular subpopulations and structures of optic nerve vulnerable to secondary degeneration, following a partial transection of the optic nerve in adult female PVG rats. Simultaneous assessment of cellular subpopulations and structures revealed oligodendroglia as the most vulnerable to DNA oxidation following injury. 5-Ethynyl-2'-deoxyuridine (EdU) was used to label cells that proliferated in the first 3 d after injury. Injury led to increases in DNA, protein, and lipid damage in oligodendrocyte progenitor cells and mature oligodendrocytes at 3 d, regardless of proliferative state, associated with a decline in the numbers of oligodendrocyte progenitor cells at 7 d. O4+ preoligodendrocytes also exhibited increased lipid peroxidation. Interestingly, EdU+ mature oligodendrocytes derived after injury demonstrated increased early susceptibility to DNA damage and lipid peroxidation. However, EdU- mature oligodendrocytes with high 8-hydroxyguanosine immunoreactivity were more likely to be caspase3+ By day 28, newly derived mature oligodendrocytes had significantly reduced myelin regulatory factor gene mRNA, indicating that the myelination potential of these cells may be reduced. The proportion of caspase3+ oligodendrocytes remained higher in EdU- cells. Innovative use of NanoSIMS together with traditional immunohistochemistry and in situ hybridization have enabled the first demonstration of subpopulation specific oligodendroglial vulnerability to oxidative damage, due to secondary degeneration in vivoSIGNIFICANCE STATEMENT Injury to the CNS is characterized by oxidative damage in areas adjacent to the injury. However, the cellular subpopulations and structures most vulnerable to this damage remain to be elucidated. Here we use powerful NanoSIMS techniques to show increased oxidative damage in oligodendroglia and axons and to demonstrate that cells early in the oligodendroglial lineage are the most vulnerable to DNA oxidation. Further immunohistochemical and in situ hybridization investigation reveals that mature oligodendrocytes derived after injury are more vulnerable to oxidative damage than their counterparts existing at the time of injury and have reduced myelin regulatory factor gene mRNA, yet preexisting oligodendrocytes are more likely to die.
Collapse
|
34
|
Abstract
Mild traumatic brain injury (mTBI) represents a significant public healthcare concern, accounting for the majority of all head injuries. While symptoms are generally transient, some patients go on to experience long-term cognitive impairments and additional mild impacts can result in exacerbated and persisting negative outcomes. To date, studies using a range of experimental models have reported chronic behavioral deficits in the presence of axonal injury and inflammation following repeated mTBI; assessments of oxidative stress and myelin pathology have thus far been limited. However, some models employed induced acute focal damage more suggestive of moderate–severe brain injury and are therefore not relevant to repeated mTBI. Given that the nature of mechanical loading in TBI is implicated in downstream pathophysiological changes, the mechanisms of damage and chronic consequences of single and repeated closed-head mTBI remain to be fully elucidated. This review covers literature on potential mechanisms of damage following repeated mTBI, integrating known mechanisms of pathology underlying moderate–severe TBIs, with recent studies on adult rodent models relevant to direct impact injuries rather than blast-induced damage. Pathology associated with excitotoxicity and cerebral blood flow-metabolism uncoupling, oxidative stress, cell death, blood-brain barrier dysfunction, astrocyte reactivity, microglial activation, diffuse axonal injury, and dysmyelination is discussed, followed by a summary of functional deficits and preclinical assessments of therapeutic strategies. Comprehensive characterization of the pathology underlying delayed and persisting deficits following repeated mTBI is likely to facilitate further development of therapeutic strategies to limit long-term sequelae.
Collapse
Affiliation(s)
- Brooke Fehily
- 1 Experimental and Regenerative Neurosciences, School of Biological sciences, The University of Western Australia, Perth, Western Australia, Australia
| | - Melinda Fitzgerald
- 1 Experimental and Regenerative Neurosciences, School of Biological sciences, The University of Western Australia, Perth, Western Australia, Australia.,2 Curtin Health Innovation Research Institute, Curtin University, Perth, Western Australia, Australia.,3 Perron Institute for Neurological and Translational Science, Sarich Neuroscience Research Institute, Nedlands, Western Australia, Australia
| |
Collapse
|
35
|
Chiha W, LeVaillant CJ, Bartlett CA, Hewitt AW, Melton PE, Fitzgerald M, Harvey AR. Retinal genes are differentially expressed in areas of primary versus secondary degeneration following partial optic nerve injury. PLoS One 2018; 13:e0192348. [PMID: 29425209 PMCID: PMC5806857 DOI: 10.1371/journal.pone.0192348] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2017] [Accepted: 01/20/2018] [Indexed: 11/19/2022] Open
Abstract
BACKGROUND Partial transection (PT) of the optic nerve is an established experimental model of secondary degeneration in the central nervous system. After a dorsal transection, retinal ganglion cells (RGCs) with axons in ventral optic nerve are intact but vulnerable to secondary degeneration, whereas RGCs in dorsal retina with dorsal axons are affected by primary and secondary injuries. Using microarray, we quantified gene expression changes in dorsal and ventral retina at 1 and 7 days post PT, to characterize pathogenic pathways linked to primary and secondary degeneration. RESULTS In comparison to uninjured retina Cryba1, Cryba2 and Crygs, were significantly downregulated in injured dorsal retina at days 1 and 7. While Ecel1, Timp1, Mt2A and CD74, which are associated with reducing excitotoxicity, oxidative stress and inflammation, were significantly upregulated. Genes associated with oxygen binding pathways, immune responses, cytokine receptor activity and apoptosis were enriched in dorsal retina at day 1 after PT. Oxygen binding and apoptosis remained enriched at day 7, as were pathways involved in extracellular matrix modification. Fewer changes were observed in ventral retina at day 1 after PT, most associated with the regulation of protein homodimerization activity. By day 7, apoptosis, matrix organization and signal transduction pathways were enriched. Discriminant analysis was also performed for specific functional gene groups to compare expression intensities at each time point. Altered expression of selected genes (ATF3, GFAP, Ecel1, TIMP1, Tp53) and proteins (GFAP, ECEL1 and ATF3) were semi-quantitatively assessed by qRT-PCR and immunohistochemistry respectively. CONCLUSION There was an acute and complex primary injury response in dorsal retina indicative of a dynamic interaction between neuroprotective and neurodegenerative events; ventral retina vulnerable to secondary degeneration showed a delayed injury response. Both primary and secondary injury resulted in the upregulation of numerous genes linked to RGC death, but differences in the nature of these changes strongly suggest that death occurred via different molecular mechanisms.
Collapse
Affiliation(s)
- Wissam Chiha
- Experimental and Regenerative Neurosciences, The University of Western Australia, Crawley, WA, Australia
- School of Human Sciences, The University of Western Australia, Crawley, WA, Australia
- School of Biological Sciences, The University of Western Australia, Crawley, WA, Australia
| | - Chrisna J. LeVaillant
- School of Human Sciences, The University of Western Australia, Crawley, WA, Australia
| | - Carole A. Bartlett
- School of Biological Sciences, The University of Western Australia, Crawley, WA, Australia
| | - Alex W. Hewitt
- Lions Eye Institute, The University of Western Australia, Nedlands, WA, Australia
| | - Phillip E. Melton
- Curtin/UWA Centre for Genetic Origins of Health and Disease, School of Biomedical Science, The University of Western Australia and Curtin University, Bentley, WA, Australia
| | - Melinda Fitzgerald
- Experimental and Regenerative Neurosciences, The University of Western Australia, Crawley, WA, Australia
- School of Biological Sciences, The University of Western Australia, Crawley, WA, Australia
- Perron Institute for Neurological and Translational Science, QEII Medical Centre, Nedlands, WA, Australia
- Curtin Health Innovation Research Institute, Curtin University, Bentley, WA, Australia
| | - Alan R. Harvey
- Experimental and Regenerative Neurosciences, The University of Western Australia, Crawley, WA, Australia
- School of Human Sciences, The University of Western Australia, Crawley, WA, Australia
- Perron Institute for Neurological and Translational Science, QEII Medical Centre, Nedlands, WA, Australia
- * E-mail:
| |
Collapse
|
36
|
van der Merwe Y, Faust AE, Conner I, Gu X, Feturi F, Zhao W, Leonard B, Roy S, Gorantla VS, Venkataramanan R, Washington KM, Wagner WR, Steketee MB. An Elastomeric Polymer Matrix, PEUU-Tac, Delivers Bioactive Tacrolimus Transdurally to the CNS in Rat. EBioMedicine 2017; 26:47-59. [PMID: 29208469 PMCID: PMC5832622 DOI: 10.1016/j.ebiom.2017.11.017] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2017] [Revised: 11/10/2017] [Accepted: 11/20/2017] [Indexed: 12/13/2022] Open
Abstract
Central nervous system (CNS) neurons fail to regrow injured axons, often resulting in permanently lost neurologic function. Tacrolimus is an FDA-approved immunosuppressive drug with known neuroprotective and neuroregenerative properties in the CNS. However, tacrolimus is typically administered systemically and blood levels required to effectively treat CNS injuries can lead to lethal, off-target organ toxicity. Thus, delivering tacrolimus locally to CNS tissues may provide therapeutic control over tacrolimus levels in CNS tissues while minimizing off-target toxicity. Herein we show an electrospun poly(ester urethane) urea and tacrolimus elastomeric matrix (PEUU-Tac) can deliver tacrolimus trans-durally to CNS tissues. In an acute CNS ischemia model in rat, the optic nerve (ON) was clamped for 10s and then PEUU-Tac was used as an ON wrap and sutured around the injury site. Tacrolimus was detected in PEUU-Tac wrapped ONs at 24 h and 14 days, without significant increases in tacrolimus blood levels. Similar to systemically administered tacrolimus, PEUU-Tac locally decreased glial fibrillary acidic protein (GFAP) at the injury site and increased growth associated protein-43 (GAP-43) expression in ischemic ONs from the globe to the chiasm, consistent with decreased astrogliosis and increased retinal ganglion cell (RGC) axon growth signaling pathways. These initial results suggest PEUU-Tac is a biocompatible elastic matrix that delivers bioactive tacrolimus trans-durally to CNS tissues without significantly increasing tacrolimus blood levels and off-target toxicity. PEUU-Tac locally delivers tacrolimus to CNS tissues PEUU-Tac positively modulates CNS tissue remodeling PEUU-Tac minimizes off-target tacrolimus toxicity
Central nervous system (CNS) injury typically results in permanently lost neurological function. Tacrolimus is an FDA-approved drug used during organ transplantation that also has CNS neuroprotective and neuroregenerative properties. However, tacrolimus is typically delivered systemically in the blood and delivering effective concentrations to CNS tissues requires tacrolimus blood levels that can lead to adverse side effects in multiple organs. Herein we show that PEUU-Tac, a tacrolimus-eluting matrix, can locally deliver tacrolimus to injured CNS tissues without increasing blood levels, suggesting PEUU-Tac can be used to treat CNS injuries locally while minimizing adverse side effects.
Collapse
Affiliation(s)
- Yolandi van der Merwe
- Department of Ophthalmology, University of Pittsburgh, Pittsburgh, PA, United States; McGowan Institute for Regenerative Medicine, University of Pittsburgh, Pittsburgh, PA, United States; Department of Bioengineering, University of Pittsburgh, Pittsburgh, PA, United States
| | - Anne E Faust
- Department of Ophthalmology, University of Pittsburgh, Pittsburgh, PA, United States; McGowan Institute for Regenerative Medicine, University of Pittsburgh, Pittsburgh, PA, United States
| | - Ian Conner
- Department of Ophthalmology, University of Pittsburgh, Pittsburgh, PA, United States; McGowan Institute for Regenerative Medicine, University of Pittsburgh, Pittsburgh, PA, United States
| | - Xinzhu Gu
- McGowan Institute for Regenerative Medicine, University of Pittsburgh, Pittsburgh, PA, United States; Department of Surgery, University of Pittsburgh, Pittsburgh, PA, United States
| | - Firuz Feturi
- McGowan Institute for Regenerative Medicine, University of Pittsburgh, Pittsburgh, PA, United States; Department of Pharmaceutical Sciences, University of Pittsburgh, Pittsburgh, PA, United States
| | - Wenchen Zhao
- Department of Pharmaceutical Sciences, University of Pittsburgh, Pittsburgh, PA, United States
| | - Bianca Leonard
- McGowan Institute for Regenerative Medicine, University of Pittsburgh, Pittsburgh, PA, United States; Department of Neuroscience, University of Pittsburgh, Pittsburgh, PA, United States
| | - Souvik Roy
- McGowan Institute for Regenerative Medicine, University of Pittsburgh, Pittsburgh, PA, United States; Department of Neuroscience, University of Pittsburgh, Pittsburgh, PA, United States
| | - Vijay S Gorantla
- McGowan Institute for Regenerative Medicine, University of Pittsburgh, Pittsburgh, PA, United States; Departments of Surgery, Ophthalmology and Bioengineering, Wake Forest School of Medicine, Wake Forest Institute of Regenerative Medicine, Winston Salem, NC, United States
| | - Raman Venkataramanan
- McGowan Institute for Regenerative Medicine, University of Pittsburgh, Pittsburgh, PA, United States; Department of Pharmaceutical Sciences, University of Pittsburgh, Pittsburgh, PA, United States; Department of Pathology, University of Pittsburgh, Pittsburgh, PA, United States
| | - Kia M Washington
- McGowan Institute for Regenerative Medicine, University of Pittsburgh, Pittsburgh, PA, United States; Department of Plastic Surgery, University of Pittsburgh, Pittsburgh, PA, United States; VA Pittsburgh Healthcare System, Pittsburgh, PA, United States
| | - William R Wagner
- McGowan Institute for Regenerative Medicine, University of Pittsburgh, Pittsburgh, PA, United States; Department of Bioengineering, University of Pittsburgh, Pittsburgh, PA, United States; Department of Surgery, University of Pittsburgh, Pittsburgh, PA, United States
| | - Michael B Steketee
- Department of Ophthalmology, University of Pittsburgh, Pittsburgh, PA, United States; Center for Neuroscience, University of Pittsburgh, Pittsburgh, PA, United States; McGowan Institute for Regenerative Medicine, University of Pittsburgh, Pittsburgh, PA, United States; Department of Neuroscience, University of Pittsburgh, Pittsburgh, PA, United States.
| |
Collapse
|
37
|
O'Hare Doig RL, Chiha W, Giacci MK, Yates NJ, Bartlett CA, Smith NM, Hodgetts SI, Harvey AR, Fitzgerald M. Specific ion channels contribute to key elements of pathology during secondary degeneration following neurotrauma. BMC Neurosci 2017; 18:62. [PMID: 28806920 PMCID: PMC5557315 DOI: 10.1186/s12868-017-0380-1] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2017] [Accepted: 08/05/2017] [Indexed: 01/24/2023] Open
Abstract
BACKGROUND Following partial injury to the central nervous system, cells beyond the initial injury site undergo secondary degeneration, exacerbating loss of neurons, compact myelin and function. Changes in Ca2+ flux are associated with metabolic and structural changes, but it is not yet clear how flux through specific ion channels contributes to the various pathologies. Here, partial optic nerve transection in adult female rats was used to model secondary degeneration. Treatment with combinations of three ion channel inhibitors was used as a tool to investigate which elements of oxidative and structural damage related to long term functional outcomes. The inhibitors employed were the voltage gated Ca2+ channel inhibitor Lomerizine (Lom), the Ca2+ permeable AMPA receptor inhibitor YM872 and the P2X7 receptor inhibitor oxATP. RESULTS Following partial optic nerve transection, hyper-phosphorylation of Tau and acetylated tubulin immunoreactivity were increased, and Nogo-A immunoreactivity was decreased, indicating that axonal changes occurred acutely. All combinations of ion channel inhibitors reduced hyper-phosphorylation of Tau and increased Nogo-A immunoreactivity at day 3 after injury. However, only Lom/oxATP or all three inhibitors in combination significantly reduced acetylated tubulin immunoreactivity. Most combinations of ion channel inhibitors were effective in restoring the lengths of the paranode and the paranodal gap, indicative of the length of the node of Ranvier, following injury. However, only all three inhibitors in combination restored to normal Ankyrin G length at the node of Ranvier. Similarly, HNE immunoreactivity and loss of oligodendrocyte precursor cells were only limited by treatment with all three ion channel inhibitors in combination. CONCLUSIONS Data indicate that inhibiting any of a range of ion channels preserves certain elements of axon and node structure and limits some oxidative damage following injury, whereas ionic flux through all three channels must be inhibited to prevent lipid peroxidation and preserve Ankyrin G distribution and OPCs.
Collapse
Affiliation(s)
- Ryan L O'Hare Doig
- Experimental and Regenerative Neurosciences, School of Biological Sciences, The University of Western Australia, Crawley, WA, 6009, Australia.,Experimental and Regenerative Neurosciences, School of Human Sciences, The University of Western Australia, Crawley, WA, 6009, Australia
| | - Wissam Chiha
- Experimental and Regenerative Neurosciences, School of Biological Sciences, The University of Western Australia, Crawley, WA, 6009, Australia.,Experimental and Regenerative Neurosciences, School of Human Sciences, The University of Western Australia, Crawley, WA, 6009, Australia
| | - Marcus K Giacci
- Experimental and Regenerative Neurosciences, School of Biological Sciences, The University of Western Australia, Crawley, WA, 6009, Australia
| | - Nathanael J Yates
- Experimental and Regenerative Neurosciences, School of Biological Sciences, The University of Western Australia, Crawley, WA, 6009, Australia
| | - Carole A Bartlett
- Experimental and Regenerative Neurosciences, School of Biological Sciences, The University of Western Australia, Crawley, WA, 6009, Australia
| | - Nicole M Smith
- Experimental and Regenerative Neurosciences, School of Biological Sciences, The University of Western Australia, Crawley, WA, 6009, Australia.,Experimental and Regenerative Neurosciences, School of Chemistry and Biochemistry, The University of Western Australia, Crawley, WA, 6009, Australia
| | - Stuart I Hodgetts
- Experimental and Regenerative Neurosciences, School of Human Sciences, The University of Western Australia, Crawley, WA, 6009, Australia.,Perron Institute for Neurological and Translational Science, Verdun St, Nedlands, WA, 6009, Australia
| | - Alan R Harvey
- Experimental and Regenerative Neurosciences, School of Human Sciences, The University of Western Australia, Crawley, WA, 6009, Australia.,Perron Institute for Neurological and Translational Science, Verdun St, Nedlands, WA, 6009, Australia
| | - Melinda Fitzgerald
- Experimental and Regenerative Neurosciences, School of Biological Sciences, The University of Western Australia, Crawley, WA, 6009, Australia. .,Curtin Health Innovation Research Institute, Curtin University, Perth, WA, Australia. .,Perron Institute for Neurological and Translational Science, Verdun St, Nedlands, WA, 6009, Australia.
| |
Collapse
|
38
|
Yi J, Puyang Z, Feng L, Duan L, Liang P, Backman V, Liu X, Zhang HF. Optical Detection of Early Damage in Retinal Ganglion Cells in a Mouse Model of Partial Optic Nerve Crush Injury. Invest Ophthalmol Vis Sci 2017; 57:5665-5671. [PMID: 27784071 PMCID: PMC5089219 DOI: 10.1167/iovs.16-19955] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
Purpose Elastic light backscattering spectroscopy (ELBS) has exquisite sensitivity to the ultrastructural properties of tissue and thus has been applied to detect various diseases associated with ultrastructural alterations in their early stages. This study aims to test whether ELBS can detect early damage in retinal ganglion cells (RGCs). Methods We used a mouse model of partial optic nerve crush (pONC) to induce rapid RGC death. We confirmed RGC loss by axon counting and characterized the changes in retinal morphology by optical coherence tomography (OCT) and in retinal function by full-field electroretinogram (ERG), respectively. To quantify the ultrastructural properties, elastic backscattering spectroscopic analysis was implemented in the wavelength-dependent images recorded by reflectance confocal microscopy. Results At 3 days post-pONC injury, no significant change was found in the thickness of the RGC layer or in the mean amplitude of the oscillatory potentials measured by OCT and ERG, respectively; however, we did observe a significantly decreased number of axons compared with the controls. At 3 days post-pONC, we used ELBS to calculate the ultrastructural marker (D), the shape factor quantifying the shape of the local mass density correlation functions. It was significantly reduced in the crushed eyes compared with the controls, indicating the ultrastructural fragmentation in the crushed eyes. Conclusions Elastic light backscattering spectroscopy detected ultrastructural neuronal damage in RGCs following the pONC injury when OCT and ERG tests appeared normal. Our study suggests a potential clinical method for detecting early neuronal damage prior to anatomical alterations in the nerve fiber and ganglion cell layers.
Collapse
Affiliation(s)
- Ji Yi
- Department of Biomedical Engineering, Northwestern University, Evanston, Illinois, United States
| | - Zhen Puyang
- School of Biomedical Engineering, Shanghai Jiao Tong University, Shanghai, China 3Department of Ophthalmology, Northwestern University, Chicago, Illinois, United States
| | - Liang Feng
- Department of Ophthalmology, Northwestern University, Chicago, Illinois, United States
| | - Lian Duan
- Department of Biomedical Engineering, Northwestern University, Evanston, Illinois, United States
| | - Peiji Liang
- School of Biomedical Engineering, Shanghai Jiao Tong University, Shanghai, China
| | - Vadim Backman
- Department of Biomedical Engineering, Northwestern University, Evanston, Illinois, United States
| | - Xiaorong Liu
- Department of Ophthalmology, Northwestern University, Chicago, Illinois, United States 4Department of Neurobiology, Northwestern University, Evanston, Illinois, United States
| | - Hao F Zhang
- Department of Biomedical Engineering, Northwestern University, Evanston, Illinois, United States 3Department of Ophthalmology, Northwestern University, Chicago, Illinois, United States
| |
Collapse
|
39
|
Yates NJ, Lydiard S, Fehily B, Weir G, Chin A, Bartlett CA, Alderson J, Fitzgerald M. Repeated mild traumatic brain injury in female rats increases lipid peroxidation in neurons. Exp Brain Res 2017; 235:2133-2149. [PMID: 28417146 DOI: 10.1007/s00221-017-4958-8] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2016] [Accepted: 04/07/2017] [Indexed: 11/30/2022]
Abstract
Negative outcomes of mild traumatic brain injury (mTBI) can be exacerbated by repeated insult. Animal models of repeated closed-head mTBI provide the opportunity to define acute pathological mechanisms as the number of mTBI increases. Furthermore, little is known about the effects of mTBI impact site, and how this may affect brain function. We use a closed head, weight drop model of mTBI that allows head movement following impact, in adult female rats to determine the role of the number and location of mTBI on brain pathology and behaviour. Biomechanical assessment of two anatomically well-defined mTBI impact sites were used, anterior (bregma) and posterior (lambda). Location of the impact had no significant effect on impact forces (450 N), and the weight impact locations were on average 5.4 mm from the desired impact site. No between location vertical linear head kinematic differences were observed immediately following impact, however, in the 300 ms post-impact, significantly higher mean vertical head displacement and velocity were observed in the mTBI lambda trials. Breaches of the blood brain barrier were observed with three mTBI over bregma, associated with immunohistochemical indicators of damage. However, an increased incidence of hairline fractures of the skull and macroscopic haemorrhaging made bregma an unsuitable impact location to model repeated mTBI. Repeated mTBI over lambda did not cause skull fractures and were examined more comprehensively, with outcomes following one, two or three mTBI or sham, delivered at 1 day intervals, assessed on days 1-4. We observe a mild behavioural phenotype, with subtle deficits in cognitive function, associated with no identifiable neuroanatomical or inflammatory changes. However, an increase in lipid peroxidation in a subset of cortical neurons following two mTBI indicates increasing oxidative damage with repeated injury in female rats, supported by increased amyloid precursor protein immunoreactivity with three mTBI. This study of acute events following closed head mTBI identifies lipid peroxidation in neurons at the same time as cognitive deficits. Our study adds to existing literature, providing biomechanics data and demonstrating mild cognitive disturbances associated with diffuse injury, predominantly to grey matter, acutely following repeated mTBI.
Collapse
Affiliation(s)
- Nathanael J Yates
- Experimental and Regenerative Neurosciences, School of Biological Sciences, The University of Western Australia, Perth, Australia
| | - Stephen Lydiard
- Experimental and Regenerative Neurosciences, School of Biological Sciences, The University of Western Australia, Perth, Australia
| | - Brooke Fehily
- Experimental and Regenerative Neurosciences, School of Biological Sciences, The University of Western Australia, Perth, Australia
| | - Gillian Weir
- School of Sport Science, Exercise and Health, The University of Western Australia, Perth, WA, 6009, Australia
| | - Aaron Chin
- School of Sport Science, Exercise and Health, The University of Western Australia, Perth, WA, 6009, Australia
| | - Carole A Bartlett
- Experimental and Regenerative Neurosciences, School of Biological Sciences, The University of Western Australia, Perth, Australia
| | - Jacqueline Alderson
- School of Sport Science, Exercise and Health, The University of Western Australia, Perth, WA, 6009, Australia.,Auckland University of Technology, Sports Performance Research Institute New Zealand (SPRINZ), Auckland, New Zealand
| | - Melinda Fitzgerald
- Experimental and Regenerative Neurosciences, School of Biological Sciences, The University of Western Australia, Perth, Australia. .,Curtin Health Innovation Research Institute, Curtin University, Bentley, Australia. .,Perron Institute for Nerurological and Translational Science, Sarich Neuroscience Research Institute, Verdun St, Nedlands, WA, 6009, Australia.
| |
Collapse
|
40
|
Chan KC, Zhou IY, Liu SS, van der Merwe Y, Fan SJ, Hung VK, Chung SK, Wu WT, So KF, Wu EX. Longitudinal Assessments of Normal and Perilesional Tissues in Focal Brain Ischemia and Partial Optic Nerve Injury with Manganese-enhanced MRI. Sci Rep 2017; 7:43124. [PMID: 28230106 PMCID: PMC5322351 DOI: 10.1038/srep43124] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2016] [Accepted: 01/19/2017] [Indexed: 01/07/2023] Open
Abstract
Although manganese (Mn) can enhance brain tissues for improving magnetic resonance imaging (MRI) assessments, the underlying neural mechanisms of Mn detection remain unclear. In this study, we used Mn-enhanced MRI to test the hypothesis that different Mn entry routes and spatiotemporal Mn distributions can reflect different mechanisms of neural circuitry and neurodegeneration in normal and injured brains. Upon systemic administration, exogenous Mn exhibited varying transport rates and continuous redistribution across healthy rodent brain nuclei over a 2-week timeframe, whereas in rodents following photothrombotic cortical injury, transient middle cerebral artery occlusion, or neonatal hypoxic-ischemic brain injury, Mn preferentially accumulated in perilesional tissues expressing gliosis or oxidative stress within days. Intravitreal Mn administration to healthy rodents not only allowed tracing of primary visual pathways, but also enhanced the hippocampus and medial amygdala within a day, whereas partial transection of the optic nerve led to MRI detection of degrading anterograde Mn transport at the primary injury site and the perilesional tissues secondarily over 6 weeks. Taken together, our results indicate the different Mn transport dynamics across widespread projections in normal and diseased brains. Particularly, perilesional brain tissues may attract abnormal Mn accumulation and gradually reduce anterograde Mn transport via specific Mn entry routes.
Collapse
Affiliation(s)
- Kevin C Chan
- NeuroImaging Laboratory, University of Pittsburgh, Pittsburgh, Pennsylvania, United States.,UPMC Eye Center, Eye and Ear Institute, Ophthalmology and Visual Science Research Center, Department of Ophthalmology, University of Pittsburgh, Pittsburgh, Pennsylvania, United States.,Department of Bioengineering, Swanson School of Engineering, University of Pittsburgh, Pittsburgh, Pennsylvania, United States.,Center for the Neural Basis of Cognition, University of Pittsburgh and Carnegie Mellon University, Pittsburgh, Pennsylvania, United States.,Louis J. Fox Center for Vision Restoration, University of Pittsburgh, Pittsburgh, Pennsylvania, United States.,New York University (NYU) Langone Eye Center, NYU Langone Medical Center, Department of Ophthalmology, NYU School of Medicine, New York, New York, United States.,Department of Electrical and Electronic Engineering, The University of Hong Kong, Pokfulam, Hong Kong, China
| | - Iris Y Zhou
- Department of Electrical and Electronic Engineering, The University of Hong Kong, Pokfulam, Hong Kong, China.,Athinoula A. Martinos Center for Biomedical Imaging, Department of Radiology, Massachusetts General Hospital and Harvard Medical School, Charlestown, Massachusetts, United States
| | - Stanley S Liu
- NeuroImaging Laboratory, University of Pittsburgh, Pittsburgh, Pennsylvania, United States
| | - Yolandi van der Merwe
- NeuroImaging Laboratory, University of Pittsburgh, Pittsburgh, Pennsylvania, United States.,UPMC Eye Center, Eye and Ear Institute, Ophthalmology and Visual Science Research Center, Department of Ophthalmology, University of Pittsburgh, Pittsburgh, Pennsylvania, United States.,Department of Bioengineering, Swanson School of Engineering, University of Pittsburgh, Pittsburgh, Pennsylvania, United States
| | - Shu-Juan Fan
- Department of Electrical and Electronic Engineering, The University of Hong Kong, Pokfulam, Hong Kong, China
| | - Victor K Hung
- School of Biomedical Sciences, The University of Hong Kong, Pokfulam, Hong Kong, China
| | - Sookja K Chung
- School of Biomedical Sciences, The University of Hong Kong, Pokfulam, Hong Kong, China.,Department of Ophthalmology, The University of Hong Kong, Pokfulam, Hong Kong, China
| | - Wu-Tian Wu
- School of Biomedical Sciences, The University of Hong Kong, Pokfulam, Hong Kong, China
| | - Kwok-Fai So
- School of Biomedical Sciences, The University of Hong Kong, Pokfulam, Hong Kong, China.,Department of Ophthalmology, The University of Hong Kong, Pokfulam, Hong Kong, China
| | - Ed X Wu
- Department of Electrical and Electronic Engineering, The University of Hong Kong, Pokfulam, Hong Kong, China.,School of Biomedical Sciences, The University of Hong Kong, Pokfulam, Hong Kong, China
| |
Collapse
|
41
|
Neuroinflammation as Fuel for Axonal Regeneration in the Injured Vertebrate Central Nervous System. Mediators Inflamm 2017; 2017:9478542. [PMID: 28203046 PMCID: PMC5288536 DOI: 10.1155/2017/9478542] [Citation(s) in RCA: 86] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2016] [Revised: 12/05/2016] [Accepted: 12/25/2016] [Indexed: 01/19/2023] Open
Abstract
Damage to the central nervous system (CNS) is one of the leading causes of morbidity and mortality in elderly, as repair after lesions or neurodegenerative disease usually fails because of the limited capacity of CNS regeneration. The causes underlying this limited regenerative potential are multifactorial, but one critical aspect is neuroinflammation. Although classically considered as harmful, it is now becoming increasingly clear that inflammation can also promote regeneration, if the appropriate context is provided. Here, we review the current knowledge on how acute inflammation is intertwined with axonal regeneration, an important component of CNS repair. After optic nerve or spinal cord injury, inflammatory stimulation and/or modification greatly improve the regenerative outcome in rodents. Moreover, the hypothesis of a beneficial role of inflammation is further supported by evidence from adult zebrafish, which possess the remarkable capability to repair CNS lesions and even restore functionality. Lastly, we shed light on the impact of aging processes on the regenerative capacity in the CNS of mammals and zebrafish. As aging not only affects the CNS, but also the immune system, the regeneration potential is expected to further decline in aged individuals, an element that should definitely be considered in the search for novel therapeutic strategies.
Collapse
|
42
|
Maes ME, Schlamp CL, Nickells RW. BAX to basics: How the BCL2 gene family controls the death of retinal ganglion cells. Prog Retin Eye Res 2017; 57:1-25. [PMID: 28064040 DOI: 10.1016/j.preteyeres.2017.01.002] [Citation(s) in RCA: 130] [Impact Index Per Article: 18.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2016] [Revised: 12/22/2016] [Accepted: 01/03/2017] [Indexed: 12/19/2022]
Abstract
Retinal ganglion cell (RGC) death is the principal consequence of injury to the optic nerve. For several decades, we have understood that the RGC death process was executed by apoptosis, suggesting that there may be ways to therapeutically intervene in this cell death program and provide a more direct treatment to the cells and tissues affected in diseases like glaucoma. A major part of this endeavor has been to elucidate the molecular biological pathways active in RGCs from the point of axonal injury to the point of irreversible cell death. A major component of this process is the complex interaction of members of the BCL2 gene family. Three distinct family members of proteins orchestrate the most critical junction in the apoptotic program of RGCs, culminating in the activation of pro-apoptotic BAX. Once active, BAX causes irreparable damage to mitochondria, while precipitating downstream events that finish off a dying ganglion cell. This review is divided into two major parts. First, we summarize the extent of knowledge of how BCL2 gene family proteins interact to facilitate the activation and function of BAX. This area of investigation has rapidly changed over the last few years and has yielded a dramatically different mechanistic understanding of how the intrinsic apoptotic program is run in mammalian cells. Second, we provided a comprehensive analysis of nearly two decades of investigation of the role of BAX in the process of RGC death, much of which has provided many important insights into the overall pathophysiology of diseases like glaucoma.
Collapse
Affiliation(s)
- Margaret E Maes
- Department of Ophthalmology and Visual Sciences, University of Wisconsin-Madison, Madison, WI, USA
| | - Cassandra L Schlamp
- Department of Ophthalmology and Visual Sciences, University of Wisconsin-Madison, Madison, WI, USA
| | - Robert W Nickells
- Department of Ophthalmology and Visual Sciences, University of Wisconsin-Madison, Madison, WI, USA.
| |
Collapse
|
43
|
Yates NJ, Giacci MK, O'Hare Doig RL, Chiha W, Ashworth BE, Kenna J, Bartlett CA, Fitzgerald M. Delayed treatment of secondary degeneration following acute optic nerve transection using a combination of ion channel inhibitors. Neural Regen Res 2017; 12:307-316. [PMID: 28400815 PMCID: PMC5361517 DOI: 10.4103/1673-5374.200814] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
Studies have shown that a combined application of several ion channel inhibitors immediately after central nervous system injury can inhibit secondary degeneration. However, for clinical use, it is necessary to determine how long after injury the combined treatment of several ion channel inhibitors can be delayed and efficacy maintained. In this study, we delivered Ca2+ entry-inhibiting P2X7 receptor antagonist oxidized-ATP and AMPA receptor antagonist YM872 to the optic nerve injury site via an iPRECIO@ pump immediately, 6 hours, 24 hours and 7 days after partial optic nerve transection surgery. In addition, all of the ion channel inhibitor treated rats were administered with calcium channel antagonist lomerizine hydrochloride. It is important to note that as a result of implantation of the particular pumps required for programmable delivery of therapeutics directly to the injury site, seromas occurred in a significant proportion of animals, indicating infection around the pumps in these animals. Improvements in visual function were observed only when treatment was delayed by 6 hours; phosphorylated Tau was reduced when treatment was delayed by 24 hours or 7 days. Improvements in structure of node/paranode of Ranvier and reductions in oxidative stress indicators were also only observed when treatment was delayed for 6 hours, 24 hours, or 7 days. Benefits of ion channel inhibitors were only observed with time-delayed treatment, suggesting that delayed therapy of Ca2+ ion channel inhibitors produces better neuroprotective effects on secondary degeneration, at least in the presence of seromas.
Collapse
Affiliation(s)
- Nathanael J Yates
- Department of Experimental and Regenerative Neurosciences, School of Animal Biology, The University of Western Australia, Crawley, Western Australia, Australia
| | - Marcus K Giacci
- Department of Experimental and Regenerative Neurosciences, School of Animal Biology, The University of Western Australia, Crawley, Western Australia, Australia
| | - Ryan L O'Hare Doig
- Department of Experimental and Regenerative Neurosciences, School of Animal Biology, The University of Western Australia, Crawley, Western Australia, Australia; Department of Experimental and Regenerative Neurosciences, School of Anatomy, Physiology and Human Biology, The University of Western Australia, Crawley, Western Australia, Australia
| | - Wissam Chiha
- Department of Experimental and Regenerative Neurosciences, School of Animal Biology, The University of Western Australia, Crawley, Western Australia, Australia; Department of Experimental and Regenerative Neurosciences, School of Anatomy, Physiology and Human Biology, The University of Western Australia, Crawley, Western Australia, Australia
| | - Bethany E Ashworth
- Department of Experimental and Regenerative Neurosciences, School of Animal Biology, The University of Western Australia, Crawley, Western Australia, Australia
| | - Jade Kenna
- Department of Experimental and Regenerative Neurosciences, School of Animal Biology, The University of Western Australia, Crawley, Western Australia, Australia
| | - Carole A Bartlett
- Department of Experimental and Regenerative Neurosciences, School of Animal Biology, The University of Western Australia, Crawley, Western Australia, Australia
| | - Melinda Fitzgerald
- Department of Experimental and Regenerative Neurosciences, School of Animal Biology, The University of Western Australia, Crawley, Western Australia, Australia
| |
Collapse
|
44
|
O'Hare Doig RL, Bartlett CA, Smith NM, Hodgetts SI, Dunlop SA, Hool L, Fitzgerald M. Specific combinations of ion channel inhibitors reduce excessive Ca 2+ influx as a consequence of oxidative stress and increase neuronal and glial cell viability in vitro. Neuroscience 2016; 339:450-462. [PMID: 27725216 DOI: 10.1016/j.neuroscience.2016.10.005] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2016] [Revised: 09/15/2016] [Accepted: 10/02/2016] [Indexed: 01/02/2023]
Abstract
Combinations of Ca2+ channel inhibitors have been proposed as an effective means to prevent excess Ca2+ flux and death of neurons and glia following neurotrauma in vivo. However, it is not yet known if beneficial outcomes such as improved viability have been due to direct effects on intracellular Ca2+ concentrations. Here, the effects of combinations of Lomerizine (Lom), 2,3-dioxo-7-(1H-imidazol-1-yl)6-nitro-1,2,3,4-tetrahydro-1-quinoxalinyl]acetic acid monohydrate (YM872), 3,5-dimethyl-1-adamantanamine (memantine (Mem)) and/or adenosine 5'-triphosphate periodate oxidized sodium salt (oxATP) to block voltage-gated Ca2+ channels, Ca2+ permeable α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA) receptors, NMDA receptors and purinergic P2X7 receptors (P2X7R) respectively, on Ca2+ concentration and viability of rat primary mixed cortical (MC) cultures exposed to hydrogen peroxide (H2O2) insult, were assessed. The contribution of ryanodine-sensitive intracellular stores to intracellular Ca2+ concentration was also assessed. Live cell calcium imaging revealed that a 30min H2O2 insult induced a slow increase in intracellular Ca2+, in part from intracellular sources, associated with loss of cell viability by 6h. Most combinations of inhibitors that included oxATP significantly decreased Ca2+ influx and increased cell viability when administered simultaneously with H2O2. However, reductions in intracellular Ca2+ concentration were not always linked to improved cell viability. Examination of the density of specific cell subpopulations demonstrated that most combinations of inhibitors that included oxATP preserved NG2+ non-oligodendroglial cells, but preservation of astrocytes and neurons required additional inhibitors. Olig2+ oligodendroglia and ED-1+ activated microglia/macrophages were not preserved by any of the inhibitor combinations. These data indicate that following H2O2 insult, limiting intracellular Ca2+ entry via P2X7R is generally associated with increased cell viability. Protection of NG2+ non-oligodendroglial cells by Ca2+ channel inhibitor combinations may contribute to observed beneficial outcomes in vivo.
Collapse
Affiliation(s)
- Ryan L O'Hare Doig
- Experimental and Regenerative Neurosciences, The University of Western Australia, Crawley, Western Australia, Australia; School of Animal Biology, The University of Western Australia, Crawley, Western Australia, Australia; School of Anatomy, Physiology and Human Biology, The University of Western Australia, Crawley, Western Australia, Australia
| | - Carole A Bartlett
- Experimental and Regenerative Neurosciences, The University of Western Australia, Crawley, Western Australia, Australia; School of Animal Biology, The University of Western Australia, Crawley, Western Australia, Australia
| | - Nicole M Smith
- Experimental and Regenerative Neurosciences, The University of Western Australia, Crawley, Western Australia, Australia; School of Animal Biology, The University of Western Australia, Crawley, Western Australia, Australia; School of Chemistry and Biochemistry, The University of Western Australia, Crawley, Western Australia, Australia
| | - Stuart I Hodgetts
- Experimental and Regenerative Neurosciences, The University of Western Australia, Crawley, Western Australia, Australia; School of Anatomy, Physiology and Human Biology, The University of Western Australia, Crawley, Western Australia, Australia
| | - Sarah A Dunlop
- Experimental and Regenerative Neurosciences, The University of Western Australia, Crawley, Western Australia, Australia; School of Animal Biology, The University of Western Australia, Crawley, Western Australia, Australia
| | - Livia Hool
- School of Anatomy, Physiology and Human Biology, The University of Western Australia, Crawley, Western Australia, Australia; Victor Chang Cardiac Research Institute, Sydney, New South Wales, Australia
| | - Melinda Fitzgerald
- Experimental and Regenerative Neurosciences, The University of Western Australia, Crawley, Western Australia, Australia; School of Animal Biology, The University of Western Australia, Crawley, Western Australia, Australia.
| |
Collapse
|
45
|
Automatic quantitative analysis of experimental primary and secondary retinal neurodegeneration: implications for optic neuropathies. Cell Death Discov 2016. [DOI: 10.1038/cddiscovery.2016.31 ecollection 2016] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022] Open
|
46
|
Automatic quantitative analysis of experimental primary and secondary retinal neurodegeneration: implications for optic neuropathies. Cell Death Discov 2016; 2:16031. [PMID: 27551521 PMCID: PMC4979431 DOI: 10.1038/cddiscovery.2016.31] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2016] [Accepted: 04/15/2016] [Indexed: 01/03/2023] Open
Abstract
Secondary neurodegeneration is thought to play an important role in the pathology of neurodegenerative disease, which potential therapies may target. However, the quantitative assessment of the degree of secondary neurodegeneration is difficult. The present study describes a novel algorithm from which estimates of primary and secondary degeneration are computed using well-established rodent models of partial optic nerve transection (pONT) and ocular hypertension (OHT). Brn3-labelled retinal ganglion cells (RGCs) were identified in whole-retinal mounts from which RGC density, nearest neighbour distances and regularity indices were determined. The spatial distribution and rate of RGC loss were assessed and the percentage of primary and secondary degeneration in each non-overlapping segment was calculated. Mean RGC number (82 592±681) and RGC density (1695±23.3 RGC/mm2) in naïve eyes were comparable with previous studies, with an average decline in RGC density of 71±17 and 23±5% over the time course of pONT and OHT models, respectively. Spatial analysis revealed greatest RGC loss in the superior and central retina in pONT, but significant RGC loss in the inferior retina from 3 days post model induction. In comparison, there was no significant difference between superior and inferior retina after OHT induction, and RGC loss occurred mainly along the superior/inferior axis (~30%) versus the nasal–temporal axis (~15%). Intriguingly, a significant loss of RGCs was also observed in contralateral eyes in experimental OHT. In conclusion, a novel algorithm to automatically segment Brn3a-labelled retinal whole-mounts into non-overlapping segments is described, which enables automated spatial and temporal segmentation of RGCs, revealing heterogeneity in the spatial distribution of primary and secondary degenerative processes. This method provides an attractive means to rapidly determine the efficacy of neuroprotective therapies with implications for any neurodegenerative disorder affecting the retina.
Collapse
|
47
|
Ashworth BE, Stephens E, Bartlett CA, Serghiou S, Giacci MK, Williams A, Hart NS, Fitzgerald M. Comparative assessment of phototherapy protocols for reduction of oxidative stress in partially transected spinal cord slices undergoing secondary degeneration. BMC Neurosci 2016; 17:21. [PMID: 27194427 PMCID: PMC4872332 DOI: 10.1186/s12868-016-0259-6] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2015] [Accepted: 05/11/2016] [Indexed: 12/28/2022] Open
Abstract
BACKGROUND Red/near-infrared light therapy (R/NIR-LT) has been developed as a treatment for a range of conditions, including injury to the central nervous system (CNS). However, clinical trials have reported variable or sub-optimal outcomes, possibly because there are few optimized treatment protocols for the different target tissues. Moreover, the low absolute, and wavelength dependent, transmission of light by tissues overlying the target site make accurate dosing problematic. RESULTS In order to optimize light therapy treatment parameters, we adapted a mouse spinal cord organotypic culture model to the rat, and characterized myelination and oxidative stress following a partial transection injury. The ex vivo model allows a more accurate assessment of the relative effect of different illumination wavelengths (adjusted for equal quantal intensity) on the target tissue. Using this model, we assessed oxidative stress following treatment with four different wavelengths of light: 450 nm (blue); 510 nm (green); 660 nm (red) or 860 nm (infrared) at three different intensities: 1.93 × 10(16) (low); 3.85 × 10(16) (intermediate) and 7.70 × 10(16) (high) photons/cm(2)/s. We demonstrate that the most effective of the tested wavelengths to reduce immunoreactivity of the oxidative stress indicator 3-nitrotyrosine (3NT) was 660 nm. 860 nm also provided beneficial effects at all tested intensities, significantly reducing oxidative stress levels relative to control (p ≤ 0.05). CONCLUSIONS Our results indicate that R/NIR-LT is an effective antioxidant therapy, and indicate that effective wavelengths and ranges of intensities of treatment can be adapted for a variety of CNS injuries and conditions, depending upon the transmission properties of the tissue to be treated.
Collapse
Affiliation(s)
- Bethany Eve Ashworth
- />Experimental and Regenerative Neurosciences, School of Animal Biology, The University of Western Australia, Crawley, WA Australia
- />Department of Biology and Biochemistry, The University of Bath, Bath, UK
| | - Emma Stephens
- />Experimental and Regenerative Neurosciences, School of Animal Biology, The University of Western Australia, Crawley, WA Australia
- />Department of Biology and Biochemistry, The University of Bath, Bath, UK
| | - Carole A. Bartlett
- />Experimental and Regenerative Neurosciences, School of Animal Biology, The University of Western Australia, Crawley, WA Australia
| | - Stylianos Serghiou
- />Centre for Regenerative Medicine, University of Edinburgh, Edinburgh, UK
| | - Marcus K. Giacci
- />Experimental and Regenerative Neurosciences, School of Animal Biology, The University of Western Australia, Crawley, WA Australia
| | - Anna Williams
- />Centre for Regenerative Medicine, University of Edinburgh, Edinburgh, UK
| | - Nathan S. Hart
- />Experimental and Regenerative Neurosciences, School of Animal Biology, The University of Western Australia, Crawley, WA Australia
- />Department of Biological Sciences, Macquarie University, Sydney, NSW 2109 Australia
| | - Melinda Fitzgerald
- />Experimental and Regenerative Neurosciences, School of Animal Biology, The University of Western Australia, Crawley, WA Australia
| |
Collapse
|
48
|
Mac Nair CE, Schlamp CL, Montgomery AD, Shestopalov VI, Nickells RW. Retinal glial responses to optic nerve crush are attenuated in Bax-deficient mice and modulated by purinergic signaling pathways. J Neuroinflammation 2016; 13:93. [PMID: 27126275 PMCID: PMC4850653 DOI: 10.1186/s12974-016-0558-y] [Citation(s) in RCA: 53] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2015] [Accepted: 04/20/2016] [Indexed: 01/14/2023] Open
Abstract
Background Retinal ganglion cell (RGC) soma death is a consequence of optic nerve damage, including in optic neuropathies like glaucoma. The activation of the innate immune network in the retina after nerve damage has been linked to RGC pathology. Since the eye is immune privileged, innate immune functions are the responsibility of the glia, specifically the microglia, astrocytes, and Müller cells that populate the retina. Glial activation, leading to the production of inflammatory cytokines, is a hallmark feature of retinal injury resulting from optic nerve damage and purported to elicit secondary degeneration of RGC somas. Methods A mouse model of optic nerve crush (ONC) was used to study retinal glial activation responses. RGC apoptosis was blocked using Bax-deficient mice. Glial activation responses were monitored by quantitative PCR and immunofluorescent labeling in retinal sections of activation markers. ATP signaling pathways were interrogated using P2X receptor agonists and antagonists and Pannexin 1 (Panx1)-deficient mice with RGC-specific deletion. Results ONC induced activation of both macroglia and microglia in the retina, and both these responses were dramatically muted if RGC death was blocked by deletion of the Bax gene. Macroglial, but not microglial, activation was modulated by purinergic receptor activation. Release of ATP after optic nerve damage was not mediated by PANX1 channels in RGCs. Conclusions RGC death in response to ONC plays a principal stimulatory role in the retinal glial activation response. Electronic supplementary material The online version of this article (doi:10.1186/s12974-016-0558-y) contains supplementary material, which is available to authorized users.
Collapse
Affiliation(s)
- Caitlin E Mac Nair
- Department of Ophthalmology and Visual Sciences, University of Wisconsin, 571A Medical Sciences-1300 University Ave, Madison, WI, 53706, USA.,Cellular and Molecular Pathology Graduate Program, University of Wisconsin-Madison, 3170-10K/L MFCB, 1685 Highland Avenue, Madison, WI, 53705, USA
| | - Cassandra L Schlamp
- Department of Ophthalmology and Visual Sciences, University of Wisconsin, 571A Medical Sciences-1300 University Ave, Madison, WI, 53706, USA
| | - Angela D Montgomery
- Department of Ophthalmology and Visual Sciences, University of Wisconsin, 571A Medical Sciences-1300 University Ave, Madison, WI, 53706, USA
| | - Valery I Shestopalov
- Department of Ophthalmology, University of Miami Miller School of Medicine, 900 N.W. 17th Street, Miami, FL, 33136, USA.,Department of Cell Biology and Anatomy, University of Miami Miller School of Medicine, 900 N.W. 17th Street, Miami, FL, 33136, USA
| | - Robert W Nickells
- Department of Ophthalmology and Visual Sciences, University of Wisconsin, 571A Medical Sciences-1300 University Ave, Madison, WI, 53706, USA.
| |
Collapse
|
49
|
Smith NM, Gachulincova I, Ho D, Bailey C, Bartlett CA, Norret M, Murphy J, Buckley A, Rigby PJ, House MJ, St Pierre T, Fitzgerald M, Iyer KS, Dunlop SA. An Unexpected Transient Breakdown of the Blood Brain Barrier Triggers Passage of Large Intravenously Administered Nanoparticles. Sci Rep 2016; 6:22595. [PMID: 26940762 PMCID: PMC4778073 DOI: 10.1038/srep22595] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2015] [Accepted: 02/18/2016] [Indexed: 12/24/2022] Open
Abstract
The highly restrictive blood-brain barrier (BBB) plays a critically important role in maintaining brain homeostasis and is pivotal for proper neuronal function. The BBB is currently considered the main limiting factor restricting the passage of large (up to 200 nm) intravenously administered nanoparticles to the brain. Breakdown of the barrier occurs as a consequence of cerebrovascular diseases and traumatic brain injury. In this article, we report that remote injuries in the CNS are also associated with BBB dysfunction. In particular, we show that a focal partial transection of the optic nerve triggers a previously unknown transient opening of the mammalian BBB that occurs in the visual centres. Importantly, we demonstrate that this transient BBB breakdown results in a dramatic change in the biodistribution of intravenously administered large polymeric nanoparticles which were previously deemed as BBB-impermeable.
Collapse
Affiliation(s)
- Nicole M Smith
- Experimental and Regenerative Neurosciences, School of Animal Biology, The University of Western Australia, Perth, WA 6009, Australia.,School of Chemistry and Biochemistry, The University of Western Australia, Perth, WA 6009, Australia
| | - Ivana Gachulincova
- Experimental and Regenerative Neurosciences, School of Animal Biology, The University of Western Australia, Perth, WA 6009, Australia
| | - Diwei Ho
- School of Chemistry and Biochemistry, The University of Western Australia, Perth, WA 6009, Australia
| | - Charlotte Bailey
- Experimental and Regenerative Neurosciences, School of Animal Biology, The University of Western Australia, Perth, WA 6009, Australia
| | - Carole A Bartlett
- Experimental and Regenerative Neurosciences, School of Animal Biology, The University of Western Australia, Perth, WA 6009, Australia
| | - Marck Norret
- School of Chemistry and Biochemistry, The University of Western Australia, Perth, WA 6009, Australia
| | - John Murphy
- Centre for Microscopy, Characterisation and Analysis, The University of Western Australia, Perth, WA 6009, Australia
| | - Alysia Buckley
- Centre for Microscopy, Characterisation and Analysis, The University of Western Australia, Perth, WA 6009, Australia
| | - Paul J Rigby
- Centre for Microscopy, Characterisation and Analysis, The University of Western Australia, Perth, WA 6009, Australia
| | - Michael J House
- School of Physics, The University of Western Australia, Perth, WA 6009, Australia
| | - Timothy St Pierre
- School of Physics, The University of Western Australia, Perth, WA 6009, Australia
| | - Melinda Fitzgerald
- Experimental and Regenerative Neurosciences, School of Animal Biology, The University of Western Australia, Perth, WA 6009, Australia
| | - K Swaminathan Iyer
- School of Chemistry and Biochemistry, The University of Western Australia, Perth, WA 6009, Australia
| | - Sarah A Dunlop
- Experimental and Regenerative Neurosciences, School of Animal Biology, The University of Western Australia, Perth, WA 6009, Australia
| |
Collapse
|
50
|
Cooper ML, Crish SD, Inman DM, Horner PJ, Calkins DJ. Early astrocyte redistribution in the optic nerve precedes axonopathy in the DBA/2J mouse model of glaucoma. Exp Eye Res 2015; 150:22-33. [PMID: 26646560 DOI: 10.1016/j.exer.2015.11.016] [Citation(s) in RCA: 67] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2015] [Revised: 11/12/2015] [Accepted: 11/23/2015] [Indexed: 10/22/2022]
Abstract
Glaucoma challenges the survival of retinal ganglion cell axons in the optic nerve through processes dependent on both aging and ocular pressure. Relevant stressors likely include complex interplay between axons and astrocytes, both in the retina and optic nerve. In the DBA/2J mouse model of pigmentary glaucoma, early progression involves axonopathy characterized by loss of functional transport prior to outright degeneration. Here we describe novel features of early pathogenesis in the DBA/2J nerve. With age the cross-sectional area of the nerve increases; this is associated generally with diminished axon packing density and survival and increased glial coverage of the nerve. However, for nerves with the highest axon density, as the nerve expands mean cross-sectional axon area enlarges as well. This early expansion was marked by disorganized axoplasm and accumulation of hyperphosphorylated neurofilamants indicative of axonopathy. Axon expansion occurs without loss up to a critical threshold for size (about 0.45-0.50 μm(2)), above which additional expansion tightly correlates with frank loss of axons. As well, early axon expansion prior to degeneration is concurrent with decreased astrocyte ramification with redistribution of processes towards the nerve edge. As axons expand beyond the critical threshold for loss, glial area resumes an even distribution from the center to edge of the nerve. We also found that early axon expansion is accompanied by reduced numbers of mitochondria per unit area in the nerve. Finally, our data indicate that both IOP and nerve expansion are associated with axon enlargement and reduced axon density for aged nerves. Collectively, our data support the hypothesis that diminished bioenergetic resources in conjunction with early nerve and glial remodeling could be a primary inducer of progression of axon pathology in glaucoma.
Collapse
Affiliation(s)
- Melissa L Cooper
- Department of Ophthalmology and Visual Sciences, Vanderbilt University Medical Center, Nashville, TN 37205, United States
| | - Samuel D Crish
- Department of Pharmaceutical Sciences, Northeast Ohio Medical University, Rootstown, OH 44272, United States
| | - Denise M Inman
- Department of Pharmaceutical Sciences, Northeast Ohio Medical University, Rootstown, OH 44272, United States
| | - Philip J Horner
- Biotherapeutics & Regenerative Medicine Research Center, Houston Methodist, Houston, TX 77030, United States
| | - David J Calkins
- Department of Ophthalmology and Visual Sciences, Vanderbilt University Medical Center, Nashville, TN 37205, United States.
| |
Collapse
|