1
|
Buscho SE, Xia F, Shi S, Lin JL, Szczesny B, Zhang W, Motamedi M, Liu H. Non-Invasive Evaluation of Retinal Vascular Alterations in a Mouse Model of Optic Neuritis Using Laser Speckle Flowgraphy and Optical Coherence Tomography Angiography. Cells 2023; 12:2685. [PMID: 38067113 PMCID: PMC10705764 DOI: 10.3390/cells12232685] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2023] [Revised: 11/04/2023] [Accepted: 11/20/2023] [Indexed: 12/18/2023] Open
Abstract
Optic neuritis, a characteristic feature of multiple sclerosis (MS), involves the inflammation of the optic nerve and the degeneration of retinal ganglion cells (RGCs). Although previous studies suggest that retinal blood flow alterations occur during optic neuritis, the precise location, the degree of impairment, and the underlying mechanisms remain unclear. In this study, we utilized two emerging non-invasive imaging techniques, laser speckle flowgraphy (LSFG) and optical coherence tomography angiography (OCTA), to investigate retinal vascular changes in a mouse model of MS, known as experimental autoimmune encephalomyelitis (EAE). We associated these changes with leukostasis, RGC injury, and the overall progression of EAE. LSFG imaging revealed a progressive reduction in retinal blood flow velocity and increased vascular resistance near the optic nerve head in the EAE model, indicating impaired ocular blood flow. OCTA imaging demonstrated significant decreases in vessel density, number of junctions, and total vessel length in the intermediate and deep capillary plexus of the EAE mice. Furthermore, our analysis of leukostasis revealed a significant increase in adherent leukocytes in the retinal vasculature of the EAE mice, suggesting the occurrence of vascular inflammation in the early development of EAE pathology. The abovechanges preceded or were accompanied by the characteristic hallmarks of optic neuritis, such as RGC loss and reduced visual acuity. Overall, our study sheds light on the intricate relationship between retinal vascular alterations and the progression of optic neuritis as well as MS clinical score. It also highlights the potential for the development of image-based biomarkers for the diagnosis and monitoring of optic neuritis as well as MS, particularly in response to emerging treatments.
Collapse
Affiliation(s)
- Seth E. Buscho
- Department of Ophthalmology and Visual Sciences, University of Texas Medical Branch, Galveston, TX 77555, USA; (S.E.B.); (F.X.); (S.S.); (J.L.L.); (B.S.); (W.Z.); (M.M.)
| | - Fan Xia
- Department of Ophthalmology and Visual Sciences, University of Texas Medical Branch, Galveston, TX 77555, USA; (S.E.B.); (F.X.); (S.S.); (J.L.L.); (B.S.); (W.Z.); (M.M.)
| | - Shuizhen Shi
- Department of Ophthalmology and Visual Sciences, University of Texas Medical Branch, Galveston, TX 77555, USA; (S.E.B.); (F.X.); (S.S.); (J.L.L.); (B.S.); (W.Z.); (M.M.)
| | - Jonathan L. Lin
- Department of Ophthalmology and Visual Sciences, University of Texas Medical Branch, Galveston, TX 77555, USA; (S.E.B.); (F.X.); (S.S.); (J.L.L.); (B.S.); (W.Z.); (M.M.)
- Department of Pharmacology and Toxicology, University of Texas Medical Branch, Galveston, TX 77555, USA
| | - Bartosz Szczesny
- Department of Ophthalmology and Visual Sciences, University of Texas Medical Branch, Galveston, TX 77555, USA; (S.E.B.); (F.X.); (S.S.); (J.L.L.); (B.S.); (W.Z.); (M.M.)
- Department of Anesthesiology, University of Texas Medical Branch, Galveston, TX 77555, USA
| | - Wenbo Zhang
- Department of Ophthalmology and Visual Sciences, University of Texas Medical Branch, Galveston, TX 77555, USA; (S.E.B.); (F.X.); (S.S.); (J.L.L.); (B.S.); (W.Z.); (M.M.)
- Department of Neurobiology, University of Texas Medical Branch, Galveston, TX 77555, USA
| | - Massoud Motamedi
- Department of Ophthalmology and Visual Sciences, University of Texas Medical Branch, Galveston, TX 77555, USA; (S.E.B.); (F.X.); (S.S.); (J.L.L.); (B.S.); (W.Z.); (M.M.)
| | - Hua Liu
- Department of Ophthalmology and Visual Sciences, University of Texas Medical Branch, Galveston, TX 77555, USA; (S.E.B.); (F.X.); (S.S.); (J.L.L.); (B.S.); (W.Z.); (M.M.)
| |
Collapse
|
2
|
Ramos-Vega M, Kjellman P, Todorov MI, Kylkilahti TM, Bäckström BT, Ertürk A, Madsen CD, Lundgaard I. Mapping of neuroinflammation-induced hypoxia in the spinal cord using optoacoustic imaging. Acta Neuropathol Commun 2022; 10:51. [PMID: 35410629 PMCID: PMC8996517 DOI: 10.1186/s40478-022-01337-4] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2021] [Accepted: 02/21/2022] [Indexed: 11/10/2022] Open
Abstract
Recent studies suggest that metabolic changes and oxygen deficiency in the central nervous system play an important role in the pathophysiology of multiple sclerosis (MS). In our present study, we investigated the changes in oxygenation and analyzed the vascular perfusion of the spinal cord in a rodent model of MS. We performed multispectral optoacoustic tomography of the lumbar spinal cord before and after an oxygen enhancement challenge in mice with experimental autoimmune encephalomyelitis (EAE), a model for MS. In addition, mice were transcardially perfused with lectin to label the vasculature and their spinal columns were optically cleared, followed by light sheet fluorescence microscopy. To analyze the angioarchitecture of the intact spine, we used VesSAP, a novel deep learning-based framework. In EAE mice, the spinal cord had lower oxygen saturation and hemoglobin concentration compared to healthy mice, indicating compromised perfusion of the spinal cord. Oxygen administration reversed hypoxia in the spinal cord of EAE mice, although the ventral region remained hypoxic. Additionally, despite the increased vascular density, we report a reduction in length and complexity of the perfused vascular network in EAE. Taken together, these findings highlight a new aspect of neuroinflammatory pathology, revealing a significant degree of hypoxia in EAE in vivo that is accompanied by changes in spinal vascular perfusion. The study also introduces optoacoustic imaging as a tractable technique with the potential to further decipher the role of hypoxia in EAE and to monitor it in MS patients.
Collapse
|
3
|
Nathoo N, Wu Y, Rogers JA, Yong VW, Dunn JF. Susceptibility weighted imaging detects prominent veins that precede or coincide with maximal motor disability in a model of multiple sclerosis: A pilot study. Mult Scler Relat Disord 2021; 54:103124. [PMID: 34243102 DOI: 10.1016/j.msard.2021.103124] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2020] [Revised: 06/20/2021] [Accepted: 06/26/2021] [Indexed: 11/27/2022]
Abstract
BACKGROUND Susceptibility weighted imaging (SWI) has detected veins in the center of white matter lesions and alterations in veins themselves in multiple sclerosis (MS) and experimental autoimmune encephalomyelitis (EAE). However, the relationship between SWI-detected venous alterations and disease progression is unclear. The objective of this study was to assess alterations in the lumbar spinal cord veins in EAE mice over the disease course using serial SWI. METHODS EAE mice (n = 8) underwent imaging for SWI using a 9.4T Bruker Avance console at baseline, 7 days (pre-motor dysfunction), 12 days (typical motor dysfunction onset), and 16-18 days (typical peak disease) post-immunization. Naïve controls were imaged alongside EAE mice (n = 3). SWI hypointensities were counted by two subjects and compared between time points. RESULTS SWI hypointensities appeared before motor dysfunction onset in most EAE mice. The ratio of SWI hypointensities to baseline was highly variable for EAE mice (0.45-6.75) while less so for controls (0.80-1.31). The time point for the maximum number of SWI hypointensities always preceded or coincided with maximum motor disability. CONCLUSION Venous alterations are detected before the onset of motor disability in some EAE mice using SWI which may relate to inflammation and/or tissue hypoxia.
Collapse
Affiliation(s)
- Nabeela Nathoo
- Department of Radiology, University of Calgary, Calgary, Alberta, Canada; Hotchkiss Brain Institute, University of Calgary, Calgary, Alberta, Canada
| | - Ying Wu
- Department of Radiology, University of Calgary, Calgary, Alberta, Canada
| | - James A Rogers
- Hotchkiss Brain Institute, University of Calgary, Calgary, Alberta, Canada; Department of Clinical Neurosciences, University of Calgary, Calgary, Alberta, Canada
| | - V Wee Yong
- Hotchkiss Brain Institute, University of Calgary, Calgary, Alberta, Canada; Department of Clinical Neurosciences, University of Calgary, Calgary, Alberta, Canada
| | - Jeff F Dunn
- Department of Radiology, University of Calgary, Calgary, Alberta, Canada; Hotchkiss Brain Institute, University of Calgary, Calgary, Alberta, Canada; Department of Clinical Neurosciences, University of Calgary, Calgary, Alberta, Canada; Experimental Imaging Centre, University of Calgary, Calgary, Alberta, Canada.
| |
Collapse
|
4
|
Halder SK, Milner R. Hypoxia in multiple sclerosis; is it the chicken or the egg? Brain 2021; 144:402-410. [PMID: 33351069 PMCID: PMC8453297 DOI: 10.1093/brain/awaa427] [Citation(s) in RCA: 26] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2020] [Revised: 09/03/2020] [Accepted: 10/14/2020] [Indexed: 12/22/2022] Open
Abstract
Over the past 50 years, intense research effort has taught us a great deal about multiple sclerosis. We know that it is the most common neurological disease affecting the young-middle aged, that it affects two to three times more females than males, and that it is characterized as an autoimmune disease, in which autoreactive T lymphocytes cross the blood-brain barrier, resulting in demyelinating lesions. But despite all the knowledge gained, a key question still remains; what is the initial event that triggers the inflammatory demyelinating process? While most research effort to date has focused on the immune system, more recently, another potential candidate has emerged: hypoxia. Specifically, a growing number of studies have described the presence of hypoxia (both 'virtual' and real) at an early stage of demyelinating lesions, and several groups, including our own, have begun to investigate how manipulation of inspired oxygen levels impacts disease progression. In this review we summarize the findings of these hypoxia studies, and in particular, address three main questions: (i) is the hypoxia found in demyelinating lesions 'virtual' or real; (ii) what causes this hypoxia; and (iii) how does manipulation of inspired oxygen impact disease progression?
Collapse
Affiliation(s)
- Sebok K Halder
- San Diego Biomedical Research Institute, 10865 Road to the Cure, Suite 100, San Diego, CA 92121, USA
| | - Richard Milner
- San Diego Biomedical Research Institute, 10865 Road to the Cure, Suite 100, San Diego, CA 92121, USA
| |
Collapse
|
5
|
Kleerekooper I, Houston S, Dubis AM, Trip SA, Petzold A. Optical Coherence Tomography Angiography (OCTA) in Multiple Sclerosis and Neuromyelitis Optica Spectrum Disorder. Front Neurol 2020; 11:604049. [PMID: 33362705 PMCID: PMC7758345 DOI: 10.3389/fneur.2020.604049] [Citation(s) in RCA: 28] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2020] [Accepted: 11/17/2020] [Indexed: 12/29/2022] Open
Abstract
Vascular changes are increasingly recognized as important factors in the pathophysiology of neuroinflammatory disease, especially in multiple sclerosis (MS). The relatively novel technology of optical coherence tomography angiography (OCTA) images the retinal and choroidal vasculature non-invasively and in a depth-resolved manner. OCTA provides an alternative quantitative measure of retinal damage, by measuring vascular density instead of structural atrophy. Preliminary results suggest OCTA is sensitive to retinal damage in early disease stages, while also having less of a "floor-effect" compared with commonly used OCT metrics, meaning it can pick up further damage in a severely atrophied retina in later stages of disease. Furthermore, it may serve as a surrogate marker for vascular pathology in the central nervous system. Data to date consistently reveal lower densities of the retinal microvasculature in both MS and neuromyelitis optica spectrum disorder (NMOSD) compared with healthy controls, even in the absence of prior optic neuritis. Exploring the timing of vascular changes relative to structural atrophy may help answer important questions about the role of hypoperfusion in the pathophysiology of neuroinflammatory disease. Finally, qualitative characteristics of retinal microvasculature may help discriminate between different neuroinflammatory disorders. There are however still issues regarding image quality and development of standardized analysis methods before OCTA can be fully incorporated into clinical practice.
Collapse
Affiliation(s)
- Iris Kleerekooper
- Department of Neuro-Ophthalmology, Moorfields Eye Hospital, London, United Kingdom.,Queen Square MS Centre, UCL Institute of Neurology and National Hospital for Neurology & Neurosurgery, London, United Kingdom
| | - Sarah Houston
- Institute of Ophthalmology, University College London, London, United Kingdom
| | - Adam M Dubis
- National Institute for Health Research, Biomedical Resource Centre at University College London, Institute of Ophthalmology and Moorfields Eye Hospital National Health Service Trust, London, United Kingdom
| | - S Anand Trip
- Queen Square MS Centre, UCL Institute of Neurology and National Hospital for Neurology & Neurosurgery, London, United Kingdom
| | - Axel Petzold
- Department of Neuro-Ophthalmology, Moorfields Eye Hospital, London, United Kingdom.,Queen Square MS Centre, UCL Institute of Neurology and National Hospital for Neurology & Neurosurgery, London, United Kingdom.,Dutch Expertise Centre of Neuro-Ophthalmology, Amsterdam UMC, Amsterdam, Netherlands
| |
Collapse
|
6
|
Desai RA, Davies AL, Del Rossi N, Tachrount M, Dyson A, Gustavson B, Kaynezhad P, Mackenzie L, van der Putten MA, McElroy D, Schiza D, Linington C, Singer M, Harvey AR, Tachtsidis I, Golay X, Smith KJ. Nimodipine Reduces Dysfunction and Demyelination in Models of Multiple Sclerosis. Ann Neurol 2020; 88:123-136. [PMID: 32293054 PMCID: PMC7737229 DOI: 10.1002/ana.25749] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2019] [Revised: 04/13/2020] [Accepted: 04/13/2020] [Indexed: 12/22/2022]
Abstract
Objective Treatment of relapses in multiple sclerosis (MS) has not advanced beyond steroid use, which reduces acute loss of function, but has little effect on residual disability. Acute loss of function in an MS model (experimental autoimmune encephalomyelitis [EAE]) is partly due to central nervous system (CNS) hypoxia, and function can promptly improve upon breathing oxygen. Here, we investigate the cause of the hypoxia and whether it is due to a deficit in oxygen supply arising from impaired vascular perfusion. We also explore whether the CNS‐selective vasodilating agent, nimodipine, may provide a therapy to restore function, and protect from demyelination in 2 MS models. Methods A variety of methods have been used to measure basic cardiovascular physiology, spinal oxygenation, mitochondrial function, and tissue perfusion in EAE. Results We report that the tissue hypoxia in EAE is associated with a profound hypoperfusion of the inflamed spinal cord. Treatment with nimodipine restores spinal oxygenation and can rapidly improve function. Nimodipine therapy also reduces demyelination in both EAE and a model of the early MS lesion. Interpretation Loss of function in EAE, and demyelination in EAE, and the model of the early MS lesion, seem to be due, at least in part, to tissue hypoxia due to local spinal hypoperfusion. Therapy to improve blood flow not only protects neurological function but also reduces demyelination. We conclude that nimodipine could be repurposed to offer substantial clinical benefit in MS. ANN NEUROL 2020 ANN NEUROL 2020;88:123–136
Collapse
Affiliation(s)
- Roshni A Desai
- Department of Neuroinflammation, UCL Queen Square Institute of Neurology, University College London, London, UK
| | - Andrew L Davies
- Department of Neuroinflammation, UCL Queen Square Institute of Neurology, University College London, London, UK
| | - Natalie Del Rossi
- Department of Neuroinflammation, UCL Queen Square Institute of Neurology, University College London, London, UK
| | - Mohamed Tachrount
- Department of Brain Repair and Rehabilitation, UCL Queen Square Institute of Neurology, University College London, London, UK.,Nuffield Department of Clinical Neurosciences, John Radcliffe Hospital, Oxford, UK
| | - Alex Dyson
- Bloomsbury Institute for Intensive Care Medicine, Division of Medicine, University College London, London, UK
| | - Britta Gustavson
- Department of Neuroinflammation, UCL Queen Square Institute of Neurology, University College London, London, UK
| | - Pardis Kaynezhad
- Biomedical Optics Research Laboratory, Department of Medical Physics and Biomedical Engineering, University College London, London, UK
| | - Lewis Mackenzie
- School of Physics & Astronomy, University of Glasgow, Glasgow, UK.,Department of Chemistry, Durham University, Durham, UK
| | - Marieke A van der Putten
- School of Physics & Astronomy, University of Glasgow, Glasgow, UK.,Northern Centre for Cancer Care, Freeman Hospital, Newcastle upon Tyne, UK
| | - Daniel McElroy
- Glasgow Biomedical Research Centre, Room B3-19, 120 University Place, University of Glasgow, Glasgow, UK
| | - Dimitra Schiza
- Department of Neuroinflammation, UCL Queen Square Institute of Neurology, University College London, London, UK
| | - Christopher Linington
- Glasgow Biomedical Research Centre, Room B3-19, 120 University Place, University of Glasgow, Glasgow, UK
| | - Mervyn Singer
- Bloomsbury Institute for Intensive Care Medicine, Division of Medicine, University College London, London, UK
| | - Andrew R Harvey
- School of Physics & Astronomy, University of Glasgow, Glasgow, UK
| | - Ilias Tachtsidis
- Biomedical Optics Research Laboratory, Department of Medical Physics and Biomedical Engineering, University College London, London, UK
| | - Xavier Golay
- Department of Brain Repair and Rehabilitation, UCL Queen Square Institute of Neurology, University College London, London, UK
| | - Kenneth J Smith
- Department of Neuroinflammation, UCL Queen Square Institute of Neurology, University College London, London, UK
| |
Collapse
|
7
|
Abstract
Susceptibility Weighted Imaging (SWI) is an established part of the clinical neuroimaging toolbox and, since its inception, has also successfully been used in various preclinical studies. Exploiting the effect of variations of magnetic susceptibility between different tissues on the externally applied, static, homogeneous magnetic field, the method visualizes venous vasculature, hemorrhages and blood degradation products, calcifications, and tissue iron deposits. The chapter describes in vivo and ex vivo protocols for preclinical SWI in rodents.
Collapse
Affiliation(s)
- Ferdinand Schweser
- Buffalo Neuroimaging Analysis Center, Department of Neurology, Jacobs School of Medicine and Biomedical Sciences, University at Buffalo, The State University of New York, Buffalo, NY, USA.
- Center for Biomedical Imaging, Clinical and Translational Science Institute, University at Buffalo, The State University of New York, Buffalo, NY, USA.
| | - Marilena Preda
- Buffalo Neuroimaging Analysis Center, Department of Neurology, Jacobs School of Medicine and Biomedical Sciences, University at Buffalo, The State University of New York, Buffalo, NY, USA
- Center for Biomedical Imaging, Clinical and Translational Science Institute, University at Buffalo, The State University of New York, Buffalo, NY, USA
| | - Robert Zivadinov
- Buffalo Neuroimaging Analysis Center, Department of Neurology, Jacobs School of Medicine and Biomedical Sciences, University at Buffalo, The State University of New York, Buffalo, NY, USA
- Center for Biomedical Imaging, Clinical and Translational Science Institute, University at Buffalo, The State University of New York, Buffalo, NY, USA
| |
Collapse
|
8
|
Abstract
Increasing evidence suggests a key role for tissue energy failure in the pathophysiology of multiple sclerosis (MS). Studies in experimental autoimmune encephalomyelitis (EAE), a commonly used model of MS, have been instrumental in illuminating the mechanisms that may be involved in compromising energy production. In this article, we review recent advances in EAE research focussing on factors that conspire to impair tissue energy metabolism, such as tissue hypoxia, mitochondrial dysfunction, production of reactive oxygen/nitrogen species, and sodium dysregulation, which are directly affected by energy insufficiency, and promote cellular damage. A greater understanding of how inflammation affects tissue energy balance may lead to novel and effective therapeutic strategies that ultimately will benefit not only people affected by MS but also people affected by the wide range of other neurological disorders in which neuroinflammation plays an important role.
Collapse
Affiliation(s)
- Roshni A Desai
- Department of Neuroinflammation, UCL Institute of Neurology, London, UK
| | - Kenneth J Smith
- Department of Neuroinflammation, UCL Institute of Neurology, London, UK
| |
Collapse
|
9
|
Mouse models of neurodegenerative disease: preclinical imaging and neurovascular component. Brain Imaging Behav 2017; 12:1160-1196. [PMID: 29075922 DOI: 10.1007/s11682-017-9770-3] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Neurodegenerative diseases represent great challenges for basic science and clinical medicine because of their prevalence, pathologies, lack of mechanism-based treatments, and impacts on individuals. Translational research might contribute to the study of neurodegenerative diseases. The mouse has become a key model for studying disease mechanisms that might recapitulate in part some aspects of the corresponding human diseases. Neurodegenerative disorders are very complicated and multifactorial. This has to be taken in account when testing drugs. Most of the drugs screening in mice are very difficult to be interpretated and often useless. Mouse models could be condiderated a 'pathway models', rather than as models for the whole complicated construct that makes a human disease. Non-invasive in vivo imaging in mice has gained increasing interest in preclinical research in the last years thanks to the availability of high-resolution single-photon emission computed tomography (SPECT), positron emission tomography (PET), high field Magnetic resonance, Optical Imaging scanners and of highly specific contrast agents. Behavioral test are useful tool to characterize different animal models of neurodegenerative pathology. Furthermore, many authors have observed vascular pathological features associated to the different neurodegenerative disorders. Aim of this review is to focus on the different existing animal models of neurodegenerative disorders, describe behavioral tests and preclinical imaging techniques used for diagnose and describe the vascular pathological features associated to these diseases.
Collapse
|