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Hosseinpour Z, Oladosu O, Liu WQ, Pike GB, Yong VW, Metz LM, Zhang Y. Distinct characteristics and severity of brain magnetic resonance imaging lesions in women and men with multiple sclerosis assessed using verified texture analysis measures. Front Neurol 2023; 14:1213377. [PMID: 37638198 PMCID: PMC10449451 DOI: 10.3389/fneur.2023.1213377] [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: 04/27/2023] [Accepted: 07/25/2023] [Indexed: 08/29/2023] Open
Abstract
Background and goal In vivo characterization of brain lesion types in multiple sclerosis (MS) has been an ongoing challenge. Based on verified texture analysis measures from clinical magnetic resonance imaging (MRI), this study aimed to develop a method to identify two extremes of brain MS lesions that were approximately severely demyelinated (sDEM) and highly remyelinated (hREM), and compare them in terms of common clinical variables. Method Texture analysis used an optimized gray-level co-occurrence matrix (GLCM) method based on FLAIR MRI from 200 relapsing-remitting MS participants. Two top-performing metrics were calculated: texture contrast and dissimilarity. Lesion identification applied a percentile approach according to texture values calculated: ≤ 25 percentile for hREM and ≥75 percentile for sDEM. Results The sDEM had a greater total normalized volume yet smaller average size, and worse MRI texture than hREM. In lesion distribution mapping, the two lesion types appeared to overlap largely in location and were present the most in the corpus callosum and periventricular regions. Further, in sDEM, the normalized volume was greater and in hREM, the average size was smaller in men than women. There were no other significant results in clinical variable-associated analyses. Conclusion Percentile statistics of competitive MRI texture measures may be a promising method for probing select types of brain MS lesion pathology. Associated findings can provide another useful dimension for improved measurement and monitoring of disease activity in MS. The different characteristics of sDEM and hREM between men and women likely adds new information to the literature, deserving further confirmation.
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Affiliation(s)
- Zahra Hosseinpour
- Department of Biomedical Engineering, Schulich School of Engineering, University of Calgary, Calgary, AB, Canada
| | - Olayinka Oladosu
- Department of Neuroscience, Faculty of Graduate Studies, University of Calgary, Calgary, AB, Canada
| | - Wei-qiao Liu
- Department of Clinical Neurosciences, University of Calgary, Calgary, AB, Canada
| | - G. Bruce Pike
- Department of Clinical Neurosciences, University of Calgary, Calgary, AB, Canada
- Department of Radiology, University of Calgary, Calgary, AB, Canada
- Hotchkiss Brain Institute, Cumming School of Medicine, University of Calgary, Calgary, AB, Canada
| | - V. Wee Yong
- Department of Clinical Neurosciences, University of Calgary, Calgary, AB, Canada
- Hotchkiss Brain Institute, Cumming School of Medicine, University of Calgary, Calgary, AB, Canada
| | - Luanne M. Metz
- Department of Clinical Neurosciences, University of Calgary, Calgary, AB, Canada
- Hotchkiss Brain Institute, Cumming School of Medicine, University of Calgary, Calgary, AB, Canada
| | - Yunyan Zhang
- Department of Clinical Neurosciences, University of Calgary, Calgary, AB, Canada
- Department of Radiology, University of Calgary, Calgary, AB, Canada
- Hotchkiss Brain Institute, Cumming School of Medicine, University of Calgary, Calgary, AB, Canada
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2
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Baldassari LE, Feng J, Clayton BLL, Oh SH, Sakaie K, Tesar PJ, Wang Y, Cohen JA. Developing therapeutic strategies to promote myelin repair in multiple sclerosis. Expert Rev Neurother 2019; 19:997-1013. [PMID: 31215271 DOI: 10.1080/14737175.2019.1632192] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
Introduction: Approved disease-modifying therapies for multiple sclerosis (MS) lessen inflammatory disease activity that causes relapses and MRI lesions. However, chronic inflammation and demyelination lead to axonal degeneration and neuronal loss, for which there currently is no effective treatment. There has been increasing interest in developing repair-promoting strategies, but there are important unanswered questions regarding the mechanisms and appropriate methods to evaluate these treatments. Areas covered: The rationale for remyelinating agents in MS is discussed, with an overview of both myelin physiology and endogenous repair mechanisms. This is followed by a discussion of the identification and development of potential remyelinating drugs. Potential biomarkers of remyelination are reviewed, including considerations regarding measuring remyelination in clinical trials. Information and data were obtained from a search of recent literature through PubMed. Peer-reviewed original articles and review articles were included. Expert opinion: There are several obstacles to the translation of potential remyelinating agents to clinical trials, particularly uncertainty regarding the most appropriate study population and method to monitor remyelination. Refinements in clinical trial design and outcome measurement, potentially via advanced imaging techniques, are needed to optimize detection of repair in patients with MS.
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Affiliation(s)
- Laura E Baldassari
- Mellen Center for MS Treatment and Research, Cleveland Clinic , Cleveland , OH , USA
| | - Jenny Feng
- Mellen Center for MS Treatment and Research, Cleveland Clinic , Cleveland , OH , USA
| | - Benjamin L L Clayton
- Department of Genetics and Genome Sciences, Case Western Reserve University School of Medicine , Cleveland , OH , USA
| | - Se-Hong Oh
- Department of Biomedical Engineering, Hankuk University of Foreign Studies , Yongin , Republic of Korea
| | - Ken Sakaie
- Imaging Institute, Cleveland Clinic , Cleveland , OH , USA
| | - Paul J Tesar
- Department of Genetics and Genome Sciences, Case Western Reserve University School of Medicine , Cleveland , OH , USA
| | - Yanming Wang
- Department of Radiology, Case Western Reserve University School of Medicine , Cleveland , OH , USA
| | - Jeffrey A Cohen
- Mellen Center for MS Treatment and Research, Cleveland Clinic , Cleveland , OH , USA
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3
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Sivakolundu DK, Hansen MR, West KL, Wang Y, Stanley T, Wilson A, McCreary M, Turner MP, Pinho MC, Newton BD, Guo X, Rypma B, Okuda DT. Three‐Dimensional Lesion Phenotyping and Physiologic Characterization Inform Remyelination Ability in Multiple Sclerosis. J Neuroimaging 2019; 29:605-614. [DOI: 10.1111/jon.12633] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2019] [Revised: 05/11/2019] [Accepted: 05/13/2019] [Indexed: 11/29/2022] Open
Affiliation(s)
- Dinesh K. Sivakolundu
- NeuroPsychometric Research Laboratory, Center for BrainHealthUniversity of Texas at Dallas Dallas TX
| | - Madison R. Hansen
- Department of Neurology & NeurotherapeuticsUT Southwestern Medical Center Dallas TX
| | - Kathryn L. West
- NeuroPsychometric Research Laboratory, Center for BrainHealthUniversity of Texas at Dallas Dallas TX
| | - Yeqi Wang
- Department of Computer ScienceUniversity of Texas at Dallas Dallas TX
| | - Thomas Stanley
- Department of Computer ScienceUniversity of Texas at Dallas Dallas TX
| | - Andrew Wilson
- Department of Computer ScienceUniversity of Texas at Dallas Dallas TX
| | | | - Monroe P. Turner
- NeuroPsychometric Research Laboratory, Center for BrainHealthUniversity of Texas at Dallas Dallas TX
| | - Marco C. Pinho
- Department of RadiologyUT Southwestern Medical Center Dallas TX
| | | | - Xiaohu Guo
- Department of Computer ScienceUniversity of Texas at Dallas Dallas TX
| | - Bart Rypma
- NeuroPsychometric Research Laboratory, Center for BrainHealthUniversity of Texas at Dallas Dallas TX
- Department of PsychiatryUT Southwestern Medical Center Dallas TX
| | - Darin T. Okuda
- Department of Neurology & NeurotherapeuticsUT Southwestern Medical Center Dallas TX
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4
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Laule C, Moore GW. Myelin water imaging to detect demyelination and remyelination and its validation in pathology. Brain Pathol 2018; 28:750-764. [PMID: 30375119 PMCID: PMC8028667 DOI: 10.1111/bpa.12645] [Citation(s) in RCA: 40] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2018] [Accepted: 07/09/2018] [Indexed: 12/11/2022] Open
Abstract
Damage to myelin is a key feature of multiple sclerosis (MS) pathology. Magnetic resonance imaging (MRI) has revolutionized our ability to detect and monitor MS pathology in vivo. Proton density, T1 and T2 can provide qualitative contrast weightings that yield superb in vivo visualization of central nervous system tissue and have proved invaluable as diagnostic and patient management tools in MS. However, standard clinical MR methods are not specific to the types of tissue damage they visualize, and they cannot detect subtle abnormalities in tissue that appears otherwise normal on conventional MRIs. Myelin water imaging is an MR method that provides in vivo measurement of myelin. Histological validation work in both human brain and spinal cord tissue demonstrates a strong correlation between myelin water and staining for myelin, validating myelin water as a marker for myelin. Myelin water varies throughout the brain and spinal cord in healthy controls, and shows good intra- and inter-site reproducibility. MS plaques show variably decreased myelin water fraction, with older lesions demonstrating the greatest myelin loss. Longitudinal study of myelin water can provide insights into the dynamics of demyelination and remyelination in plaques. Normal appearing brain and spinal cord tissues show reduced myelin water, an abnormality which becomes progressively more evident over a timescale of years. Diffusely abnormal white matter, which is evident in 20%-25% of MS patients, also shows reduced myelin water both in vivo and postmortem, and appears to originate from a primary lipid abnormality with relative preservation of myelin proteins. Active research is ongoing in the quest to refine our ability to image myelin and its perturbations in MS and other disorders of the myelin sheath.
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Affiliation(s)
- Cornelia Laule
- RadiologyUniversity of British ColumbiaVancouverBCCanada
- Pathology & Laboratory MedicineUniversity of British ColumbiaVancouverBCCanada
- Physics & AstronomyUniversity of British ColumbiaVancouverBCCanada
- International Collaboration on Repair Discoveries (ICORD)University of British ColumbiaVancouverBCCanada
| | - G.R. Wayne Moore
- Pathology & Laboratory MedicineUniversity of British ColumbiaVancouverBCCanada
- International Collaboration on Repair Discoveries (ICORD)University of British ColumbiaVancouverBCCanada
- Medicine (Neurology)University of British ColumbiaVancouverBCCanada
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5
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Variable density magnetization transfer (vdMT) imaging for 7 T MR imaging. Neuroimage 2018; 168:242-249. [DOI: 10.1016/j.neuroimage.2016.09.009] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2016] [Revised: 07/06/2016] [Accepted: 09/03/2016] [Indexed: 11/21/2022] Open
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6
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Bove RM. Why monkeys do not get multiple sclerosis (spontaneously): An evolutionary approach. EVOLUTION MEDICINE AND PUBLIC HEALTH 2018; 2018:43-59. [PMID: 29492266 PMCID: PMC5824939 DOI: 10.1093/emph/eoy002] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/28/2017] [Accepted: 11/07/2017] [Indexed: 12/20/2022]
Abstract
The goal of this review is to apply an evolutionary lens to understanding the origins of multiple sclerosis (MS), integrating three broad observations. First, only humans are known to develop MS spontaneously. Second, humans have evolved large brains, with characteristically large amounts of metabolically costly myelin. This myelin is generated over long periods of neurologic development—and peak MS onset coincides with the end of myelination. Third, over the past century there has been a disproportionate increase in the rate of MS in young women of childbearing age, paralleling increasing westernization and urbanization, indicating sexually specific susceptibility in response to changing exposures. From these three observations about MS, a life history approach leads us to hypothesize that MS arises in humans from disruption of the normal homeostatic mechanisms of myelin production and maintenance, during our uniquely long myelination period. This review will highlight under-explored areas of homeostasis in brain development, that are likely to shed new light on the origins of MS and to raise further questions about the interactions between our ancestral genes and modern environments.
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Affiliation(s)
- Riley M Bove
- Department of Neurology, UCSF, San Francisco, CA, USA
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7
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Abstract
Myelin water imaging (MWI) provides mild traumatic brain injury (mTBI) researchers with a specific myelin biomarker and helps to further elucidate microstructural and microarchitectural changes of white matter after mTBI. Improvement of scanner hardware and software with the implementation of MWI across scanner platforms will likely result in increased research regarding the role of myelin in traumatic brain injury (TBI). Future research should include detailed investigation of myelin between 2 weeks and 2 months after injury, the use of MWI in moderate and severe TBI, and investigation of the role of myelin in chronic TBI.
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Affiliation(s)
- Alexander Mark Weber
- Department of Pediatrics, Division of Neurology, Faculty of Medicine, University of British Columbia, M10 - Purdy Pavilion, 2221 Wesbrook Mall, Vancouver, British Columbia V6T 2B5, Canada.
| | - Carlos Torres
- Department of Radiology, University of Ottawa, 1053 Carling Avenue, Ottawa, Ontario K1Y 4E9, Canada; Department of Medical Imaging, The Ottawa Hospital, 1053 Carling Avenue, Ottawa, Ontario K1Y 4E9, Canada
| | - Alexander Rauscher
- Department of Pediatrics, Division of Neurology, Faculty of Medicine, University of British Columbia, M10 - Purdy Pavilion, 2221 Wesbrook Mall, Vancouver, British Columbia V6T 2B5, Canada
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8
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Abstract
We have witnessed major successes in the development of effective immunomodulatory therapies capable of reducing adaptive immune-mediated myelin damage in MS over the last 30 years. However, until it is possible to prevent MS or initiate treatment before it has already caused lesions there is a need to repair myelin damage to prevent further axonal loss. The past decade has brought remarkable advances in our understanding of oligodendrocyte biology and the related search for remyelinating therapies in humans. In this review, we first outline the basic biology of central nervous system myelin and remyelination, including a discussion of the major identified pathways and targets that might help yield CNS remyelinating drugs. In conjunction, we provide an overview of techniques that have helped identify compounds capable of promoting oligodendrocyte precursor cell differentiation and myelination. This includes the methods for both initial in vitro screening and subsequent in vivo confirmation of the target. We then review methods proposed to quantify human remyelination in vivo, including visual evoked potentials and putative imaging modalities. As the remyelination era approaches, with the announcement of the first positive trial in remyelination, we are now tasked with answering new questions regarding patient-specific factors (e.g., age) that may influence the extent and optimal therapeutic window for remyelination.
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Affiliation(s)
- Riley M Bove
- Department of Neurology Weill Institute for the Neurosciences, University of California, San Francisco, San Francisco, CA, USA.
| | - Ari J Green
- Department of Neurology Weill Institute for the Neurosciences, University of California, San Francisco, San Francisco, CA, USA.
- Department of Ophthalmology, University of California, San Francisco, San Francisco, CA, USA.
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9
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Abstract
Myelin is critical for healthy brain function. An accurate in vivo measure of myelin content has important implications for understanding brain plasticity and neurodegenerative diseases. Myelin water imaging is a magnetic resonance imaging method which can be used to visualize myelination in the brain and spinal cord in vivo. This review presents an overview of myelin water imaging data acquisition and analysis, post-mortem validation work, findings in both animal and human studies and a brief discussion about other MR techniques purported to provide in vivo myelin content. Multi-echo T2 relaxation approaches continue to undergo development and whole-brain imaging time now takes less than 10 minutes; the standard analysis method for this type of data acquisition is a non-negative least squares approach. Alternate methods including the multi-flip angle gradient echo mcDESPOT are also being used for myelin water imaging. Histological validation studies in animal and human brain and spinal cord tissue demonstrate high specificity of myelin water imaging for myelin. Potential confounding factors for in vivo myelin water fraction measurement include the presence of myelin debris and magnetization exchange processes. Myelin water imaging has successfully been used to study animal models of injury, applied in healthy human controls and can be used to assess damage and injury in conditions such as multiple sclerosis, neuromyelitis optica, schizophrenia, phenylketonuria, neurofibromatosis, niemann pick’s disease, stroke and concussion. Other quantitative magnetic resonance approaches that are sensitive to, but not specific for, myelin exist including magnetization transfer, diffusion tensor imaging and T1 weighted imaging.
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Affiliation(s)
- Alex L MacKay
- Department of Radiology, University of British Columbia, Vancouver, Canada.,Department of Physics and Astronomy, University of British Columbia, Vancouver, Canada
| | - Cornelia Laule
- Department of Radiology, University of British Columbia, Vancouver, Canada.,Department of Pathology & Laboratory Medicine, University of British Columbia, Vancouver, Canada.,International Collaboration on Repair Discoveries, University of British Columbia, Vancouver, Canada
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10
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Schwartzbach CJ, Grove RA, Brown R, Tompson D, Then Bergh F, Arnold DL. Lesion remyelinating activity of GSK239512 versus placebo in patients with relapsing-remitting multiple sclerosis: a randomised, single-blind, phase II study. J Neurol 2016; 264:304-315. [PMID: 27888416 PMCID: PMC5306088 DOI: 10.1007/s00415-016-8341-7] [Citation(s) in RCA: 74] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2016] [Revised: 11/02/2016] [Accepted: 11/08/2016] [Indexed: 10/27/2022]
Abstract
Histamine H3 receptor blockade may enhance lesion remyelination in multiple sclerosis (MS). The efficacy (using a magnetic resonance imaging marker of myelination, magnetisation transfer ratio [MTR]), safety and pharmacokinetics of GSK239512, a potent and brain penetrant H3 receptor antagonist/inverse agonist on lesion remyelination in relapsing-remitting MS (RRMS) were assessed. This was a phase II, randomised, parallel-group, placebo-controlled, double-blind (sponsor-unblinded), international, multicentre study (NCT01772199). Patients aged 18-50 with RRMS, receiving intramuscular interferon-β1a or glatiramer acetate, were randomised 1:1 to once-daily oral GSK239512 or placebo, up-titrated over 4-5 weeks to a maximum tolerable dose up to 80 µg and maintained until Week 48. The co-primary endpoints were mean changes in post-lesion MTR in gadolinium-enhanced (GdE) or Delta-MTR defined lesions from pre-lesion values. Adverse events (AE) and withdrawals were monitored. Of the 131 patients randomised, 114 patients completed the study (GSK239512, n = 51; placebo, n = 63) and 27 (GSK239512) and 28 (placebo) patients contributed lesions to the primary analysis. GSK239512 was associated with positive effect sizes of 0.344 [90% confidence interval (CI) 0.018, 0.671] and 0.243 (90% CI -0.112, 0.598) for adjusted mean changes in the normalised MTR for GdE and Delta-MTR lesions, respectively. The overall incidence of AEs was similar between GSK239512 and placebo during the treatment phase although some AEs including insomnia were more common with GSK239512, particularly during the titration period. A small but positive effect of GSK239512 on remyelination was observed. MTR assessment represents a promising method for detecting lesion remyelination in RRMS.
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Affiliation(s)
| | | | | | - Debra Tompson
- GSK, Gunnels Wood Road, Stevenage, Hertfordshire, UK
| | | | - Douglas L Arnold
- McGill University, Montreal, QC, Canada.,Department of Neurology, NeuroRx Research, Montreal, QC, Canada
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11
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Atkins HL, Bowman M, Allan D, Anstee G, Arnold DL, Bar-Or A, Bence-Bruckler I, Birch P, Bredeson C, Chen J, Fergusson D, Halpenny M, Hamelin L, Huebsch L, Hutton B, Laneuville P, Lapierre Y, Lee H, Martin L, McDiarmid S, O'Connor P, Ramsay T, Sabloff M, Walker L, Freedman MS. Immunoablation and autologous haemopoietic stem-cell transplantation for aggressive multiple sclerosis: a multicentre single-group phase 2 trial. Lancet 2016; 388:576-85. [PMID: 27291994 DOI: 10.1016/s0140-6736(16)30169-6] [Citation(s) in RCA: 221] [Impact Index Per Article: 27.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
BACKGROUND Strong immunosuppression, including chemotherapy and immune-depleting antibodies followed by autologous haemopoietic stem-cell transplantation (aHSCT), has been used to treat patients with multiple sclerosis, improving control of relapsing disease. We addressed whether near-complete immunoablation followed by immune cell depleted aHSCT would result in long-term control of multiple sclerosis. METHODS We did this phase 2 single-arm trial at three hospitals in Canada. We enrolled patients with multiple sclerosis, aged 18-50 years with poor prognosis, ongoing disease activity, and an Expanded Disability Status Scale of 3.0-6.0. Autologous CD34 selected haemopoietic stem-cell grafts were collected after mobilisation with cyclophosphamide and filgrastim. Immunoablation with busulfan, cyclophosphamide, and rabbit anti-thymocyte globulin was followed by aHSCT. The primary outcome was multiple sclerosis activity-free survival (events were clinical relapse, appearance of a new or Gd-enhancing lesion on MRI, and sustained progression of Expanded Disability Status Scale score). This study was registered at ClinicalTrials.gov, NCT01099930. FINDINGS Between diagnosis and aHSCT, 24 patients had 167 clinical relapses over 140 patient-years with 188 Gd-enhancing lesions on 48 pre-aHSCT MRI scans. Median follow-up was 6.7 years (range 3.9-12.7). The primary outcome, multiple sclerosis activity-free survival at 3 years after transplantation was 69.6% (95% CI 46.6-84.2). With up to 13 years of follow-up after aHSCT, no relapses occurred and no Gd enhancing lesions or new T2 lesions were seen on 314 MRI sequential scans. The rate of brain atrophy decreased to that expected for healthy controls. One of 24 patients died of transplantation-related complications. 35% of patients had a sustained improvement in their Expanded Disability Status Scale score. INTERPRETATION We describe the first treatment to fully halt all detectable CNS inflammatory activity in patients with multiple sclerosis for a prolonged period in the absence of any ongoing disease-modifying drugs. Furthermore, many of the patients had substantial recovery of neurological function despite their disease's aggressive nature. FUNDING Multiple Sclerosis Scientific Research Foundation.
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Affiliation(s)
- Harold L Atkins
- Ottawa Hospital Research Institute, Ottawa, ON, Canada; The Ottawa Hospital Blood and Marrow Transplant Program, Ottawa, ON, Canada; Department of Medicine, University of Ottawa, Ottawa, ON, Canada.
| | - Marjorie Bowman
- Ottawa Hospital Research Institute, Ottawa, ON, Canada; The Ottawa Hospital MS Clinic, Ottawa, ON, Canada
| | - David Allan
- Ottawa Hospital Research Institute, Ottawa, ON, Canada; The Ottawa Hospital Blood and Marrow Transplant Program, Ottawa, ON, Canada; Department of Medicine, University of Ottawa, Ottawa, ON, Canada
| | - Grizel Anstee
- The Ottawa Hospital Blood and Marrow Transplant Program, Ottawa, ON, Canada
| | - Douglas L Arnold
- Department of Neurology and Neurosurgery, Montreal Neurological Institute and Hospital, McGill University, Montréal, QC, Canada; NeuroRx Research, Montreal, QC, Canada
| | - Amit Bar-Or
- Department of Neurology and Neurosurgery, Montreal Neurological Institute and Hospital, McGill University, Montréal, QC, Canada; Neuroimmunology Unit, Montreal Neurological Institute and Hospital, McGill University, Montréal, QC, Canada
| | - Isabelle Bence-Bruckler
- The Ottawa Hospital Blood and Marrow Transplant Program, Ottawa, ON, Canada; Department of Medicine, University of Ottawa, Ottawa, ON, Canada
| | - Paul Birch
- Ottawa Stem Cell Program, Canadian Blood Services, Ottawa, ON, Canada
| | - Christopher Bredeson
- Ottawa Hospital Research Institute, Ottawa, ON, Canada; The Ottawa Hospital Blood and Marrow Transplant Program, Ottawa, ON, Canada; Department of Medicine, University of Ottawa, Ottawa, ON, Canada
| | - Jacqueline Chen
- Department of Neurology and Neurosurgery, Montreal Neurological Institute and Hospital, McGill University, Montréal, QC, Canada; Department of Neurosciences, Cleveland Clinic, Cleveland, OH, USA
| | - Dean Fergusson
- Ottawa Hospital Research Institute, Ottawa, ON, Canada; Department of Medicine, University of Ottawa, Ottawa, ON, Canada
| | - Mike Halpenny
- Ottawa Stem Cell Program, Canadian Blood Services, Ottawa, ON, Canada
| | - Linda Hamelin
- The Ottawa Hospital Blood and Marrow Transplant Program, Ottawa, ON, Canada
| | - Lothar Huebsch
- The Ottawa Hospital Blood and Marrow Transplant Program, Ottawa, ON, Canada; Department of Medicine, University of Ottawa, Ottawa, ON, Canada
| | - Brian Hutton
- Ottawa Hospital Research Institute, Ottawa, ON, Canada
| | - Pierre Laneuville
- McGill University Health Center, Montreal, QC, Canada; Division of Oncology, Department of Medicine, McGill University, Montreal, QC, Canada
| | - Yves Lapierre
- Department of Neurology and Neurosurgery, Montreal Neurological Institute and Hospital, McGill University, Montréal, QC, Canada
| | - Hyunwoo Lee
- Department of Neurology and Neurosurgery, Montreal Neurological Institute and Hospital, McGill University, Montréal, QC, Canada
| | - Lisa Martin
- Ottawa Stem Cell Program, Canadian Blood Services, Ottawa, ON, Canada
| | - Sheryl McDiarmid
- The Ottawa Hospital Blood and Marrow Transplant Program, Ottawa, ON, Canada
| | - Paul O'Connor
- Division of Neurology, St Michael's Hospital, University of Toronto, Toronto, ON, Canada
| | - Timothy Ramsay
- Ottawa Hospital Research Institute, Ottawa, ON, Canada; Department of Medicine, University of Ottawa, Ottawa, ON, Canada
| | - Mitchell Sabloff
- The Ottawa Hospital Blood and Marrow Transplant Program, Ottawa, ON, Canada; Department of Medicine, University of Ottawa, Ottawa, ON, Canada
| | - Lisa Walker
- School of Psychology, University of Ottawa, Ottawa, ON, Canada; The Ottawa Hospital MS Clinic, Ottawa, ON, Canada
| | - Mark S Freedman
- Ottawa Hospital Research Institute, Ottawa, ON, Canada; Department of Medicine, University of Ottawa, Ottawa, ON, Canada; The Ottawa Hospital MS Clinic, Ottawa, ON, Canada
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12
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Abstract
The human brain rapidly develops during the final weeks of gestation and in the first two years following birth. Diffusion tensor imaging (DTI) is a unique in vivo imaging technique that allows three-dimensional visualization of the white matter anatomy in the brain. It has been considered to be a valuable tool for studying brain development in early life. In this review, we first introduce the DTI technique. We then review DTI findings on white matter development at the fetal stage and in infancy as well as DTI applications for understanding neurocognitive development and brain abnormalities in preterm infants. Finally, we discuss limitations of DTI and potential valuable imaging techniques for studying white matter myelination.
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Affiliation(s)
- Anqi Qiu
- Department of Biomedical Engineering and Clinical Imaging Research Center, National University of Singapore, 117576 Singapore;
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13
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Advanced imaging tools to investigate multiple sclerosis pathology. Presse Med 2015; 44:e159-67. [DOI: 10.1016/j.lpm.2015.02.011] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/28/2015] [Accepted: 02/23/2015] [Indexed: 12/26/2022] Open
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14
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Lin YC, Daducci A, Meskaldji DE, Thiran JP, Michel P, Meuli R, Krueger G, Menegaz G, Granziera C. Quantitative Analysis of Myelin and Axonal Remodeling in the Uninjured Motor Network After Stroke. Brain Connect 2014; 5:401-12. [PMID: 25296185 DOI: 10.1089/brain.2014.0245] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023] Open
Abstract
Contralesional brain connectivity plasticity was previously reported after stroke. This study aims at disentangling the biological mechanisms underlying connectivity plasticity in the uninjured motor network after an ischemic lesion. In particular, we measured generalized fractional anisotropy (GFA) and magnetization transfer ratio (MTR) to assess whether poststroke connectivity remodeling depends on axonal and/or myelin changes. Diffusion-spectrum imaging and magnetization transfer MRI at 3T were performed in 10 patients in acute phase, at 1 and 6 months after stroke, which was affecting motor cortical and/or subcortical areas. Ten age- and gender-matched healthy volunteers were scanned 1 month apart for longitudinal comparison. Clinical assessment was also performed in patients prior to magnetic resonance imaging (MRI). In the contralesional hemisphere, average measures and tract-based quantitative analysis of GFA and MTR were performed to assess axonal integrity and myelination along motor connections as well as their variations in time. Mean and tract-based measures of MTR and GFA showed significant changes in a number of contralesional motor connections, confirming both axonal and myelin plasticity in our cohort of patients. Moreover, density-derived features (peak height, standard deviation, and skewness) of GFA and MTR along the tracts showed additional correlation with clinical scores than mean values. These findings reveal the interplay between contralateral myelin and axonal remodeling after stroke.
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Affiliation(s)
- Ying-Chia Lin
- 1 Department of Computer Science, University of Verona , Verona, Italy
| | - Alessandro Daducci
- 2 STI/IEL/LTS5 , Ecole Polytechnique Fédérale de Lausanne, Lausanne, Switzerland
| | - Djalel Eddine Meskaldji
- 3 Institute of Bioengineering, Ecole Polytechnique Fédérale de Lausanne (EPFL), Lausanne, Switzerland .,4 Department of Radiology and Medical Informatics, University of Geneva , Geneva, Switzerland
| | - Jean-Philippe Thiran
- 2 STI/IEL/LTS5 , Ecole Polytechnique Fédérale de Lausanne, Lausanne, Switzerland
| | - Patrik Michel
- 5 Stroke Center, Department of Clinical Neurosciences, Centre Hospitalier Universitaire Vaudois, University of Lausanne , Lausanne, Switzerland
| | - Reto Meuli
- 6 Department of Radiology, Centre Hospitalier Universitaire Vaudois, University of Lausanne , Lausanne, Switzerland
| | - Gunnar Krueger
- 7 Healthcare Sector IM&WS S, Siemens Schweiz AG, Lausanne, Switzerland .,8 Advanced Clinical Imaging Technology Group, Ecole Polytechnique Fédérale de Lausanne, Lausanne, Switzerland
| | - Gloria Menegaz
- 1 Department of Computer Science, University of Verona , Verona, Italy
| | - Cristina Granziera
- 2 STI/IEL/LTS5 , Ecole Polytechnique Fédérale de Lausanne, Lausanne, Switzerland .,8 Advanced Clinical Imaging Technology Group, Ecole Polytechnique Fédérale de Lausanne, Lausanne, Switzerland .,9 Laboratoire de Recherche en Neuroimagerie and Neuroimmunology Unit, Department of Clinical Neurosciences, Centre Hospitalier Universitaire Vaudois and University of Lausanne , Lausanne, Switzerland
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15
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Haughey NJ, Zhu X, Bandaru VVR. A biological perspective of CSF lipids as surrogate markers for cognitive status in HIV. J Neuroimmune Pharmacol 2013; 8:1136-46. [PMID: 24203462 PMCID: PMC3909934 DOI: 10.1007/s11481-013-9506-0] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2013] [Accepted: 10/03/2013] [Indexed: 12/14/2022]
Abstract
The development and application of biomarkers to neurodegenerative diseases has become increasingly important in clinical practice and therapeutic trials. While substantial progress has been made at the basic science level in understanding the pathophysiology of HIV-Associated Neurocognitive Disorders (HAND), there are significant limitations in our current ability to predict the onset or trajectory of disease, and to accurately determine the effects of therapeutic interventions. Thus, the development of objective biomarkers is critical to further our understanding and treatment of HAND. In recent years, biomarker discovery efforts have largely been driven forward through the implementation of multiple "omics" approaches that include (but are not restricted to): Lipidomics, proteomics, metabolomics, genomics, transcriptomics, and advances in brain imaging approaches such as functional connectomics. In this paper we summarize our progress to date on lipidomic approaches to biomarker discovery, discuss how these data have influenced basic research on the neuropathology of HAND, and implications for the development of therapeutics that target metabolic pathways involved in lipid handling.
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Affiliation(s)
- Norman J Haughey
- Department of Neurology, Division of Neuroimmunology and Neurological Infections, The Johns Hopkins University School of Medicine, Pathology 517, 600 North Wolfe Street, Baltimore, MD, 21287, USA,
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16
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Abstract
Central nervous system inflammatory demyelinating disease can affect patients across the life span. Consensus definitions and criteria of all of the different acquired demyelinating diseases that fall on this spectrum have magnetic resonance imaging criteria. The advances of both neuroimaging techniques and important discoveries in immunology have produced an improved understanding of these conditions and classification. Neuroimaging plays a central role in the accurate diagnosis, prognosis, disease monitoring and research efforts that are being undertaken in this disease. This review focuses on the imaging spectrum of acquired demyelinating disease.
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17
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Verhey LH, Sled JG. Advanced magnetic resonance imaging in pediatric multiple sclerosis. Neuroimaging Clin N Am 2013; 23:337-54. [PMID: 23608694 DOI: 10.1016/j.nic.2012.12.011] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
This review summarizes results from studies that have applied advanced magnetic resonance (MR) imaging techniques to patients with pediatric-onset multiple sclerosis (MS), and includes a discussion of cortical imaging techniques, volumetry, magnetization transfer and diffusion tensor imaging, proton magnetic resonance spectroscopy, and functional MR imaging. Multicenter studies on the sensitivity of these techniques to natural history of disease and treatment response are required before their implementation into clinical practice.
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18
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Ishak GE, Poliakov AV, Poliachik SL, Saneto RP, Novotny EJ, McDaniel S, Ojemann JG, Shaw DWW, Friedman SD. Tract-based spatial statistical analysis of diffusion tensor imaging in pediatric patients with mitochondrial disease: widespread reduction in fractional anisotropy of white matter tracts. AJNR Am J Neuroradiol 2012; 33:1726-30. [PMID: 22499843 DOI: 10.3174/ajnr.a3045] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
BACKGROUND AND PURPOSE Often diagnosed at birth or in early childhood, mitochondrial disease presents with a variety of clinical symptoms, particularly in organs and tissues that require high energetic demand such as brain, heart, liver, and skeletal muscles. In a group of pediatric patients identified as having complex I or I/III deficits on muscle biopsy but with white matter tissue appearing qualitatively normal for age, we hypothesized that quantitative DTI analyses might unmask disturbance in microstructural integrity. MATERIALS AND METHODS In a retrospective study, DTI and structural MR brain imaging data from 10 pediatric patients with confirmed mitochondrial disease and 10 clinical control subjects were matched for age, sex, scanning parameters, and date of examination. Paired TBSS was performed to evaluate differences in FA, MD, and the separate diffusion direction terms (λr and λa). RESULTS In patients with mitochondrial disease, significant widespread reductions in FA values were shown in white matter tracts. Mean diffusivity values were significantly increased in patients, having a sparser distribution of affected regions compared with FA. Separate diffusion maps showed significant increase in λr and no significant changes in λa. CONCLUSIONS Despite qualitatively normal-appearing white matter tissues, patients with complex I or I/III deficiency have widespread microstructural changes measurable with quantitative DTI.
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Affiliation(s)
- G E Ishak
- Seattle Children's Hospital, Department of Radiology, 4800 Sandpoint Way, M/S R-5417, Seattle, Washington 98105, USA.
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19
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Zivadinov R, Dwyer MG, Hussein S, Carl E, Kennedy C, Andrews M, Hojnacki D, Heininen-Brown M, Willis L, Cherneva M, Bergsland N, Weinstock-Guttman B. Voxel-wise magnetization transfer imaging study of effects of natalizumab and IFNβ-1a in multiple sclerosis. Mult Scler 2012; 18:1125-1134. [DOI: 10.1177/1352458511433304] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 08/30/2023]
Abstract
Objective: To determine the effects of intravenous natalizumab and intramuscular interferon beta-1a (IFNβ-1a) on the volume of white-matter (WM) lesions and normal appearing brain tissue (NABT) undergoing voxel-wise (VW) increases in magnetization transfer ratio (MTR) suggestive of remyelination in patients with relapsing multiple sclerosis. Methods: This prospective, open-label, single-blinded study enrolled patients with relapsing–remitting multiple sclerosis (RRMS) and relapsing secondary progressive multiple sclerosis (RSPMS) as well as a group of age/sex-matched healthy controls ( n=22). Patients with multiple sclerosis were assigned to receive natalizumab monotherapy ( n=77; RRMS/RSPMS) or intramuscular IFNβ-1a ( n=26) as either monotherapy (RRMS) or combined with pulsed i.v. methylprednisolone, as needed (RSPMS). The primary endpoint was the two-year change in volume of NABT VWMTR, by quantifying the number of voxels that increased (suggesting remyelination) or decreased (suggesting demyelination) in their MTR value. Results: The volume of tissue undergoing increases in VWMTR was significantly larger in natalizumab compared with IFNβ-1a-treated patients (year 1: p=0.001 in NABT and p<0.006 in WM lesions; year 2: p=0.008 in NABT) and compared with healthy control subjects (year 1: p=0.05 and year 2: p=0.007 in NABT). The larger volume within NABT undergoing decreases in VWMTR was detected in multiple sclerosis patients compared with healthy controls ( p<0.001), and in the IFNβ-1a group compared with the natalizumab group (year 1: p=0.05; year 2: p=0.002). One patient on natalizumab died from progressive multifocal leukoencephalopathy eight months after completing the study. Conclusion: Natalizumab may promote remyelination and stabilize demyelination in lesions and NABT in relapsing multiple sclerosis, compared with intramuscular IFNβ-1a.
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Affiliation(s)
- R Zivadinov
- Buffalo Neuroimaging Analysis Center, State University of New York, Buffalo, USA
- The Jacobs Neurological Institute, Department of Neurology, University at Buffalo, State University of New York, Buffalo, USA
| | - MG Dwyer
- Buffalo Neuroimaging Analysis Center, State University of New York, Buffalo, USA
| | - S Hussein
- Buffalo Neuroimaging Analysis Center, State University of New York, Buffalo, USA
| | - E Carl
- Buffalo Neuroimaging Analysis Center, State University of New York, Buffalo, USA
| | - C Kennedy
- Buffalo Neuroimaging Analysis Center, State University of New York, Buffalo, USA
| | - M Andrews
- Buffalo Neuroimaging Analysis Center, State University of New York, Buffalo, USA
| | - D Hojnacki
- Buffalo Neuroimaging Analysis Center, State University of New York, Buffalo, USA
| | - M Heininen-Brown
- Buffalo Neuroimaging Analysis Center, State University of New York, Buffalo, USA
| | - L Willis
- Buffalo Neuroimaging Analysis Center, State University of New York, Buffalo, USA
| | - M Cherneva
- Buffalo Neuroimaging Analysis Center, State University of New York, Buffalo, USA
| | - N Bergsland
- Buffalo Neuroimaging Analysis Center, State University of New York, Buffalo, USA
| | - B Weinstock-Guttman
- Buffalo Neuroimaging Analysis Center, State University of New York, Buffalo, USA
- The Jacobs Neurological Institute, Department of Neurology, University at Buffalo, State University of New York, Buffalo, USA
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20
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Alexander AL, Hurley SA, Samsonov AA, Adluru N, Hosseinbor AP, Mossahebi P, Tromp DPM, Zakszewski E, Field AS. Characterization of cerebral white matter properties using quantitative magnetic resonance imaging stains. Brain Connect 2012; 1:423-46. [PMID: 22432902 DOI: 10.1089/brain.2011.0071] [Citation(s) in RCA: 330] [Impact Index Per Article: 27.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
The image contrast in magnetic resonance imaging (MRI) is highly sensitive to several mechanisms that are modulated by the properties of the tissue environment. The degree and type of contrast weighting may be viewed as image filters that accentuate specific tissue properties. Maps of quantitative measures of these mechanisms, akin to microstructural/environmental-specific tissue stains, may be generated to characterize the MRI and physiological properties of biological tissues. In this article, three quantitative MRI (qMRI) methods for characterizing white matter (WM) microstructural properties are reviewed. All of these measures measure complementary aspects of how water interacts with the tissue environment. Diffusion MRI, including diffusion tensor imaging, characterizes the diffusion of water in the tissues and is sensitive to the microstructural density, spacing, and orientational organization of tissue membranes, including myelin. Magnetization transfer imaging characterizes the amount and degree of magnetization exchange between free water and macromolecules like proteins found in the myelin bilayers. Relaxometry measures the MRI relaxation constants T1 and T2, which in WM have a component associated with the water trapped in the myelin bilayers. The conduction of signals between distant brain regions occurs primarily through myelinated WM tracts; thus, these methods are potential indicators of pathology and structural connectivity in the brain. This article provides an overview of the qMRI stain mechanisms, acquisition and analysis strategies, and applications for these qMRI stains.
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Affiliation(s)
- Andrew L Alexander
- Department of Medical Physics, University of Wisconsin, Madison, Wisconsin 53705, USA.
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21
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Anik Y, Demirci A, Efendi H, Bulut SSD, Celebi I, Komsuoglu S. Evaluation of normal appearing white matter in multiple sclerosis: comparison of diffusion magnetic resonance, magnetization transfer imaging and multivoxel magnetic resonance spectroscopy findings with expanded disability status scale. Clin Neuroradiol 2011; 21:207-15. [PMID: 21847666 DOI: 10.1007/s00062-011-0091-4] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2011] [Accepted: 07/18/2011] [Indexed: 11/25/2022]
Abstract
PURPOSE The aim of this study was to determine diffusion magnetic resonance imaging (MRI), magnetization transfer (MT) imaging and multivoxel MR spectroscopy findings in plaques, periplaque white matter and normal appearing white matter (NAWM) regions in multiple sclerosis (MS) and to correlate the findings with the expanded disability status scale (EDSS). METHODS A total of 30 patients with MS and 30 healthy control subjects were studied and apparent diffusion coefficient (ADC) values, MT ratio (MTR), N-acetyl-aspartate/creatine (NAA/Cr) and choline/creatine (Cho/Cr) ratios were measured in plaques, periplaques and NAWM regions and compared with the control subjects. RESULTS The MTR and NAA/Cr ratio were decreased more in plaques than periplaques and NAWM, in contrast ADC values and Cho/Cr ratios were highest in plaques and higher in periplaques than in NAWM. Decreased MTR and NAA/Cr in NAWM demonstrated moderate inverse correlations (r = - 0.604, p < 0.001 and r = - 0.494, p < 0.001, respectively) while Cho/Cr ratios and ADC of NAWM demonstrated weak linear correlations (r = 0.370, p = 0.004, r = 0.297, p = 0.021 respectively) with EDSS. CONCLUSIONS The MS, MTR and MR spectroscopy findings were found to be useful for detecting subtle abnormalities in NAWM. Although ADC values were significantly altered in plaque and periplaque regions a significance difference was not found in NAWM.
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Affiliation(s)
- Y Anik
- Department of Radiology, School of Medicine, Kocaeli University, 41380, Umuttepe Kocaeli, Turkey.
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22
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Stankoff B, Freeman L, Aigrot MS, Chardain A, Dollé F, Williams A, Galanaud D, Armand L, Lehericy S, Lubetzki C, Zalc B, Bottlaender M. Imaging central nervous system myelin by positron emission tomography in multiple sclerosis using [methyl-¹¹C]-2-(4'-methylaminophenyl)- 6-hydroxybenzothiazole. Ann Neurol 2011; 69:673-80. [PMID: 21337603 DOI: 10.1002/ana.22320] [Citation(s) in RCA: 153] [Impact Index Per Article: 11.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2010] [Revised: 09/13/2010] [Accepted: 09/17/2010] [Indexed: 11/10/2022]
Abstract
OBJECTIVE Imaging of myelin tracts in vivo would greatly improve the monitoring of demyelinating diseases such as multiple sclerosis (MS). To date, no imaging technique specifically targets demyelination and remyelination. Recently, amyloid markers related to Congo red have been shown to bind to central nervous system (CNS) myelin. Here we questioned whether the thioflavine-T derivative 2-(4'-methylaminophenyl)-6-hydroxybenzothiazole (PIB), which also binds to amyloid plaques, could serve as a myelin marker. METHODS PIB fixation to myelin was studied by fluorescence in the normal and dysmyelinating mouse brain, as well as in the postmortem brain of MS patients. Positron emission tomography (PET) experiments were conducted using [¹¹C]PIB in baboons and in a proof of concept clinical study in 2 MS patients. RESULTS Applied directly on tissue sections or after intraperitoneal injection, PIB stained CNS myelin, and the decrease in the level of fixation paralleled the amount of myelin loss in a dysmyelinating mutant. In normally myelinated areas of postmortem MS brain, demyelinated and remyelinated lesions were clearly distinguishable by the differential intensity of labeling observed with PIB. PET using intravenously injected radiolabeled [¹¹C]PIB imaged CNS myelin in baboons and humans. In MS patients, the dynamic analysis of PET acquisitions allowed quantitative assessment of demyelination. INTERPRETATION PIB could be used as an imaging marker to quantify myelin loss and repair in demyelinating diseases.
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Affiliation(s)
- Bruno Stankoff
- Inserm, U975, Paris, France; Faculty of Medicine, Pierre and Marie Curie University, Paris, France.
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23
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Vavasour IM, Laule C, Li DKB, Traboulsee AL, MacKay AL. Is the magnetization transfer ratio a marker for myelin in multiple sclerosis? J Magn Reson Imaging 2011; 33:713-8. [PMID: 21563257 DOI: 10.1002/jmri.22441] [Citation(s) in RCA: 132] [Impact Index Per Article: 10.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2010] [Accepted: 10/21/2010] [Indexed: 12/19/2022] Open
Affiliation(s)
- Irene M Vavasour
- Department of Radiology, University of British Columbia, Vancouver, Canada.
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24
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Miron VE, Ludwin SK, Darlington PJ, Jarjour AA, Soliven B, Kennedy TE, Antel JP. Fingolimod (FTY720) enhances remyelination following demyelination of organotypic cerebellar slices. THE AMERICAN JOURNAL OF PATHOLOGY 2010; 176:2682-94. [PMID: 20413685 DOI: 10.2353/ajpath.2010.091234] [Citation(s) in RCA: 211] [Impact Index Per Article: 15.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Remyelination, which occurs subsequent to demyelination, contributes to functional recovery and is mediated by oligodendrocyte progenitor cells (OPCs) that have differentiated into myelinating cells. Therapeutics that impact remyelination in the CNS could be critical determinants of long-term functional outcome in multiple sclerosis (MS). Fingolimod is a S1P receptor modulator in MS clinical trials due to systemic anti-inflammatory properties, yet may impact cells within the CNS by crossing the blood-brain barrier. Previous studies using isolated dissociated cultures indicate that neural cells express S1P receptors and respond to receptor engagement. Our objective was to assess the effects of fingolimod on myelin-related processes within a multicellular environment that maintains physiological cell-cell interactions, using organotypic cerebellar slice cultures. Fingolimod treatment had no impact on myelin under basal conditions. Fingolimod treatment subsequent to lysolecithin-induced demyelination enhanced remyelination and process extension by OPCs and mature oligodendrocytes, while increasing microglia numbers and immunoreactivity for the astrocytic marker glial fibrillary acidic protein. The number of phagocytosing microglia was not increased by fingolimod. Using S1P receptor specific agonists and antagonists, we determined that fingolimod-induced effects on remyelination and astrogliosis were mediated primarily through S1P3 and S1P5, whereas enhanced microgliosis was mediated through S1P1 and S1P5. Taken together, these data demonstrate that fingolimod modulates multiple neuroglial cell responses, resulting in enhanced remyelination in organotypic slice cultures that maintain the complex cellular interactions of the mammalian brain.
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Affiliation(s)
- Veronique E Miron
- Neuroimmunology Unit, McGill University, Montreal Neurological Institute, 3801 University St., Montreal, QC, Canada, H3A 2B4
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Abstract
Many promising MRI approaches for research or clinical management of multiple sclerosis (MS) have recently emerged, or are under development or refinement. Advanced MRI methods need to be assessed to determine whether they allow earlier diagnosis or better identification of phenotypes. Improved post-processing should allow more efficient and complete extraction of information from images. Magnetic resonance spectroscopy should improve in sensitivity and specificity with higher field strengths and should enable the detection of a wider array of metabolites. Diffusion imaging is moving closer to the goal of defining structural connectivity and, thereby, determining the functional significance of lesions at specific locations. Cell-specific imaging now seems feasible with new magnetic resonance contrast agents. The imaging of myelin water fraction brings the hope of providing a specific measure of myelin content. Ultra-high-field MRI increases sensitivity, but also presents new technical challenges. Here, we review these recent developments in MRI for MS, and also look forward to refinements in spinal-cord imaging, optic-nerve imaging, perfusion MRI, and functional MRI. Advances in MRI should improve our ability to diagnose, monitor, and understand the pathophysiology of MS.
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26
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Wheeler D, Bandaru VVR, Calabresi PA, Nath A, Haughey NJ. A defect of sphingolipid metabolism modifies the properties of normal appearing white matter in multiple sclerosis. ACTA ACUST UNITED AC 2008; 131:3092-102. [PMID: 18772223 PMCID: PMC2577809 DOI: 10.1093/brain/awn190] [Citation(s) in RCA: 129] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
Maintaining the appropriate complement and content of lipids in cellular membranes is critical for normal neural function. Accumulating evidence suggests that even subtle perturbations in the lipid content of neurons and myelin can disrupt their function and may contribute to myelin and axonal degradation. In this study, we determined the composition and quantified the content of lipids and sterols in normal appearing white matter (NAWM) and normal appearing grey matter (NAGM) from control and multiple sclerosis brain tissues by electrospray ionization tandem mass spectrometry. Our results suggest that in active-multiple sclerosis, there is a shift in the lipid composition of NAWM and NAGM to a higher phospholipid and lower sphingolipid content. We found that this disturbance in lipid composition was reduced in NAGM but not in NAWM of inactive-multiple sclerosis. The pattern of disturbance in lipid composition suggests a metabolic defect that causes sphingolipids to be shuttled to phospholipid production. Modelling the biophysical consequence of this change in lipid composition of NAWM indicated an increase in the repulsive force between opposing bilayers that could explain decompaction and disruption of myelin structure.
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Affiliation(s)
- David Wheeler
- Department of Neurology, Richard T Johnson Division of Neuroimmunology and Neurological Infections, The Johns Hopkins University School of Medicine, Baltimore, MD 21287, USA
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27
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Dubois-Dalcq M, Williams A, Stadelmann C, Stankoff B, Zalc B, Lubetzki C. From fish to man: understanding endogenous remyelination in central nervous system demyelinating diseases. Brain 2008; 131:1686-700. [PMID: 18474520 PMCID: PMC2516372 DOI: 10.1093/brain/awn076] [Citation(s) in RCA: 58] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
In the central nervous system (CNS) of man, evolutionary pressure has preserved some capability for remyelination while axonal regeneration is very limited. In contrast, two efficient programmes of regeneration exist in the adult fish CNS, neurite regrowth and remyelination. The rapidity of CNS remyelination is critical since it not only restores fast conduction of nerve impulses but also maintains axon integrity. If myelin repair fails, axons degenerate, leading to increased disability. In the human CNS demyelinating disease multiple sclerosis (MS), remyelination often takes place in the midst of inflammation. Here, we discuss recent studies that address the innate repair capabilities of the axon-glia unit from fish to man. We propose that expansion of this research field will help find ways to maintain or enhance spontaneous remyelination in man.
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Affiliation(s)
- Monique Dubois-Dalcq
- National Institute of Neurological Disorders and Stroke, Porter Neuroscience Research Center, Bethesda, MD 20892-3706, USA.
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28
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Miron VE, Jung CG, Kim HJ, Kennedy TE, Soliven B, Antel JP. FTY720 modulates human oligodendrocyte progenitor process extension and survival. Ann Neurol 2008; 63:61-71. [PMID: 17918267 DOI: 10.1002/ana.21227] [Citation(s) in RCA: 207] [Impact Index Per Article: 12.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
OBJECTIVE FTY720, a sphingosine-1-phosphate (S1P) receptor agonist that crosses the blood-brain barrier, is a potential immuno-therapy for multiple sclerosis. Our objective was to assess the effect of FTY720 on process extension, differentiation, and survival of human oligodendrocyte progenitor cells (OPCs), and link the functional effects with S1P receptor expression and signaling. METHODS Functional assays and receptor expression studies were conducted on A2B5+ OPCs derived from the human fetal central nervous system. Cells were treated with physiologically relevant concentrations of the active phosphorylated form of FTY720. S1P receptor/signaling modulators were used to elucidate the basis of the FTY720-induced functional responses. RESULTS Short-term (1 day) FTY720 treatment caused initial process retraction that was reversed by uncoupling S1P3 and 5 from their G protein using suramin, and with a Rho-kinase inhibitor H1152. Retraction was associated with RhoA-mediated cytoskeletal signaling and with inhibition of OPC differentiation into more mature phenotypes. Continued FTY720 treatment (2 days) induced process extension and enhanced cell survival associated with increased extracellular signal-regulated kinases 1 and 2 phosphorylation, mimicked with the S1P1-specific agonist SEW2871, but not reversed with suramin. Quantitative real-time polymerase chain reaction showed that FTY720 induced reciprocal and cyclic modulation of S1P1 and S1P5 messenger RNA levels. The observed initial downregulation of S1P5 and subsequently of S1P1 messenger RNA supports functional responses being mediated sequentially by S1P5- and later S1P1-associated signaling. INTERPRETATION FTY720 induces time-dependent modulation of S1P receptors on human OPCs with consequent functional responses that are directly relevant for the remyelination process.
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Affiliation(s)
- Veronique E Miron
- Neuroimmunology Unit, Montreal Neurological Institute, McGill University, Montreal, Quebec, Canada
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29
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Zivadinov R, Stosic M, Cox JL, Ramasamy DP, Dwyer MG. The place of conventional MRI and newly emerging MRI techniques in monitoring different aspects of treatment outcome. J Neurol 2008; 255 Suppl 1:61-74. [DOI: 10.1007/s00415-008-1009-1] [Citation(s) in RCA: 53] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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30
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Laule C, Vavasour IM, Kolind SH, Li DKB, Traboulsee TL, Moore GRW, MacKay AL. Magnetic resonance imaging of myelin. Neurotherapeutics 2007; 4:460-84. [PMID: 17599712 PMCID: PMC7479725 DOI: 10.1016/j.nurt.2007.05.004] [Citation(s) in RCA: 230] [Impact Index Per Article: 13.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022] Open
Abstract
The ability to measure myelin in vivo has great consequences for furthering our knowledge of normal development, as well as for understanding a wide range of neurological disorders. The following review summarizes the current state of myelin imaging using MR. We consider five MR techniques that have been used to study myelin: 1) conventional MR, 2) MR spectroscopy, 3) diffusion, 4) magnetization transfer, and 5) T2 relaxation. Fundamental studies involving peripheral nerve and MR/histology comparisons have aided in the interpretation and validation of MR data. We highlight a number of important findings related to myelin development, damage, and repair, and we conclude with a critical summary of the current techniques available and their potential to image myelin in vivo.
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Affiliation(s)
- Cornelia Laule
- Department of Radiology, University of British Columbia, Vancouver, BC, V6T 2B5 Canada.
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31
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Openshaw H, Atkins HL, Chen JT, de Bittencourt PRM, Griffith LM, Kerr DA, Khoury SA, Muraro PA, Nash RA, Saccardi R. Multiple sclerosis conference synopsis and discussion: cellular therapy for treatment of autoimmune diseases (October 2005). Mult Scler 2007; 12:824-5. [PMID: 17263013 DOI: 10.1177/1352458506070943] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
At a conference held in October 2005, participants presented studies on high dose immunosuppression with hematopoietic cell transplant (HCT) for multiple sclerosis (MS), including neuroimmunological and magnetic resonance imaging (MRI) mechanistic approaches, clinical registry reports, and ongoing or newly-designed protocols. A discussion panel considered questions on how to define success, timing of controlled clinical trials, difficulty in patient recruitment, and future direction of high dose therapy.
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Affiliation(s)
- H Openshaw
- Department of Neurology, City of Hope National Medical Center, 1500 E. Duarte Road, Duarte, CA 91010, USA.
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32
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Abstract
Conventional magnetic resonance imaging (MRI) has routinely been used to improve the accuracy of multiple sclerosis (MS) diagnosis and prognosis. Metrics derived from conventional MRI are now routinely used to detect therapeutic effects and extend clinical observations. However, conventional MRI measures, such as the use of lesion volume and count of gadolinium-enhancing and T2 lesions, have insufficient sensitivity and specificity to reveal the true degree of pathological changes occurring in MS. They cannot distinguish between inflammation, edema, demyelination, Wallerian degeneration, and axonal loss. In addition, they do not show a reliable correlation with clinical measures of disability and do not provide a complete assessment of therapeutic outcomes. Recent neuropathologic studies of typical chronic MS brains reveal macroscopic demyelination in cortical and deep gray matter (GM) that cannot be detected by currently available MRI techniques. Therefore, there is a pressing need for the development of newer MRI techniques to detect these lesions. Newer metrics of MRI analysis, including T1-weighted hypointense lesions, central nervous system atrophy measures, magnetization transfer imaging, magnetic resonance spectroscopy, and diffusion tensor imaging, are able to capture a more global picture of the range of tissue alterations caused by inflammation and neurodegeneration. At this time, they provide the only proof--albeit indirect--that important occult pathology is occurring in the GM. However, evidence is increasing that these nonconventional MRI measures correlate better with both existing and developing neurological impairment and disability when compared to conventional metrics.
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Affiliation(s)
- Robert Zivadinov
- Buffalo Neuroimaging Analysis Center, The Jacobs Neurological Institute, State University of New York at Buffalo, School of Medicine and Biomedical Sciences, Buffalo, New York 14203, USA
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Dhib-Jalbut S, Arnold DL, Cleveland DW, Fisher M, Friedlander RM, Mouradian MM, Przedborski S, Trapp BD, Wyss-Coray T, Yong VW. Neurodegeneration and neuroprotection in multiple sclerosis and other neurodegenerative diseases. J Neuroimmunol 2006; 176:198-215. [PMID: 16983747 DOI: 10.1016/j.jneuroim.2006.03.027] [Citation(s) in RCA: 68] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Multiple sclerosis is considered a disease of myelin destruction; Parkinson's disease (PD), one of dopaminergic neuron depletion; ALS, a disease of motor neuron death; and Alzheimer's, a disease of plaques and tangles. Although these disorders differ in important ways, they also have common pathogenic features, including inflammation, genetic mutations, inappropriate protein aggregates (e.g., Lewy bodies, amyloid plaques), and biochemical defects leading to apoptosis, such as oxidative stress and mitochondrial dysfunction. In most disorders, it remains uncertain whether inflammation and protein aggregation are neurotoxic or neuroprotective. Elucidating the mechanisms that orchestrate neuronal diseases should facilitate development of neuroprotective and neurorestorative strategies.
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Affiliation(s)
- Suhayl Dhib-Jalbut
- UMDNJ-Robert Wood Johnson Medical School, New Brunswick, NJ 08901, and The Cleveland Clinic, OH, USA.
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Meier DS, Guttmann CRG. MRI time series modeling of MS lesion development. Neuroimage 2006; 32:531-7. [PMID: 16806979 DOI: 10.1016/j.neuroimage.2006.04.181] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2005] [Revised: 03/16/2006] [Accepted: 04/05/2006] [Indexed: 11/17/2022] Open
Abstract
A mathematical model was applied to new lesion formation in multiple sclerosis, as apparent on frequent T2-weighted MRI. The pathophysiologically motivated two-process model comprises two opposing nonlinear self-limiting processes, intended to represent degenerative and reparatory processes, respectively, investigating T2 activity from a dynamic/temporal rather than a spatial/static perspective. Parametric maps were obtained from the model to characterize the MRI dynamics of lesion development, answering the questions of how long new T2 lesion activity persists, how much residual damage/hyperintensity remains and how the T2 dynamics compare to those of contrast-enhancing MRI indicating active inflammation. 997 MRI examinations were analyzed, acquired weekly to monthly from 45 patients over a 1-year period. The model was applied to all pixels within 332 new lesions, capturing the time profiles with excellent fidelity (r = 0.89 +/- 0.03 average correlation between model and image data). From this modeling perspective, the observed dynamics in new T2 lesions are in agreement with two opposing processes of longitudinal intensity change, such as inflammation and degeneration versus resorbtion and repair. On average, about one third of a new lesion consisted of transient signal change with little or no residual hyperintensity and activity of 10 weeks or less. Global lesion burden as MRI surrogate of disease activity may therefore be confounded by large amounts of transient hyperintensity. T2 activity also persisted significantly beyond the period of contrast enhancement, thereby defining MRI sensitivity toward a subacute phase of lesion development beyond blood-brain barrier patency. Concentric patterns of dynamic properties within a lesion were observed, consistent with concentric histological appearance of resulting MS plaques.
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Affiliation(s)
- Dominik S Meier
- Center for Neurological Imaging, Brigham and Women's Hospital, 221 Longwood Avenue, RF 396, Boston, MA 02115, USA.
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Zivadinov R, Leist TP. Clinical-magnetic resonance imaging correlations in multiple sclerosis. J Neuroimaging 2006; 15:10S-21S. [PMID: 16385015 DOI: 10.1177/1051228405283291] [Citation(s) in RCA: 90] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
Conventional magnetic resonance imaging (MRI) has routinely been used to improve the accuracy of multiple sclerosis (MS) diagnosis and monitoring, detect the effects of disease-modifying therapy, and refine the utility of clinical assessments. However, conventional MRI measures, such as the use of lesion volume and count of gadolinium-enhancing and T2 lesions, have insufficient sensitivity and specificity to reveal the true degree of pathological changes occurring in MS. Newer metrics of MRI analysis, including T1-weighted hypointense lesions (black holes) and central nervous system (CNS) atrophy measures, are able to capture a more global picture of the range of tissue alterations caused by inflammation, demyelination, axonal loss, and neurodegeneration. There is mounting evidence that these MRI measures correlate well with existing and developing neurological impairment and disability. In so doing, these MRI techniques can help elucidate the mechanisms underlying the pathophysiology and natural history of MS. The current understanding is that T1 black holes and CNS atrophy more accurately reflect the neurodegenerative and destructive components of the MS disease process. Therefore, the short and long-term studies that aim to measure the degree and severity of the neurodegenerative MS disease process should incorporate these MRI metrics as part of their standard routine MRI protocols.
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Affiliation(s)
- Robert Zivadinov
- Buffalo Neuroimaging Analysis Center, State University of New York at Buffalo, NY 14203, USA.
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Miron VE, Rajasekharan S, Jarjour AA, Zamvil SS, Kennedy TE, Antel JP. Simvastatin regulates oligodendroglial process dynamics and survival. Glia 2006; 55:130-43. [PMID: 17078030 DOI: 10.1002/glia.20441] [Citation(s) in RCA: 74] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
Simvastatin, a lipophilic statin that crosses the blood-brain barrier, is being evaluated as a potential therapy for multiple sclerosis (MS) due to its anti-inflammatory properties. We assessed the effects of simvastatin on cultures of rat newborn and human fetal oligodendrocyte progenitor cells (OPCs) and human adult mature oligodendrocytes (OLGs) with respect to cellular events pertaining to myelin maintenance and repair. Short-term simvastatin treatment of OPCs (1 day) induced robust process extension, enhanced differentiation to a mature phenotype, and decreased spontaneous migration. These effects were reversed by isoprenoid products and mimicked with an inhibitor of Rho kinase (ROCK), the downstream effector of the isoprenylated protein RhoA GTPase. Prolonged treatment (2 days) caused process retraction that was rescued by cholesterol, and increased cell death (4 days) partially rescued by either cholesterol or isoprenoid co-treatment. In comparison, simvastatin treatment of human mature OLGs required a longer initial time course (2 days) to induce significant process outgrowth, mimicked by inhibiting ROCK. Prolonged treatment of mature OLGs was associated with process retraction (6 days) and increased cell death (8 days). Human-derived OPCs and mature OLGs demonstrated an increased sensitivity to simvastatin relative to the rodent cells, responding to nanomolar versus micromolar concentrations. Our findings indicate the importance of considering the short- and long-term effects of systemic immunomodulatory therapies on neural cells affected by the MS disease process. (c) 2006 Wiley-Liss, Inc.
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Affiliation(s)
- Veronique E Miron
- Neuroimmunology Unit, Montreal Neurological Institute, McGill University, Montreal, Quebec, Canada
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