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Pang QQ, Zang CX, Li T, Zeng XC, Liu LX, Zhang D, Yao XS, Yu Y. Neuroprotective effect of GJ-4 against cognitive impairments in vascular dementia by improving white matter damage. PHYTOMEDICINE : INTERNATIONAL JOURNAL OF PHYTOTHERAPY AND PHYTOPHARMACOLOGY 2024; 132:155877. [PMID: 39032283 DOI: 10.1016/j.phymed.2024.155877] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/27/2024] [Revised: 07/03/2024] [Accepted: 07/12/2024] [Indexed: 07/23/2024]
Abstract
BACKGROUND White matter lesions (WMLs) are increasingly linked to the pathological process of chronic vascular dementia (VaD). An effective crocins fraction extracted from Gardenia Fructus, GJ-4, has been shown to improve cognitive function in several Alzheimer's disease models and VaD models. OBJECTIVES To explore the potential mechanisms of GJ-4 on WMLs in a chronic VaD mouse model. METHODS The chronic VaD mouse model was established, and WMLs were characterized by cerebral blood flow (CBF), behavioral tests, LFB staining, and immunohistochemistry. The anti-oxidative effect of GJ-4 was validated by examining biochemical parameters (SOD, MDA, and GSH) and the Keap1-Nrf2/HO-1 pathway. The impact of GJ-4 on lipid metabolism in WM was further investigated through lipidomic analysis. RESULTS GJ-4 significantly attenuated cognitive impairments and improved the CBF of BCAS (bilateral common carotid artery stenosis)-induced mice. Mechanism research showed that GJ-4 could enhance cognition by promoting the repair of WMLs by inhibiting oxidative stress. Furthermore, GJ-4 treatment significantly reduced chronic cerebral hypoperfusion (CCH)-induced WMLs via improving lipid metabolism disorder in the WM. CONCLUSION This research has provided valuable insights into the significance of WMLs in CCH-induced VaD and underscored the potential of GJ-4 as a therapeutic agent for improving cognitive function by targeting WMLs. These findings suggest that GJ-4 is a promising candidate for the treatment of VaD.
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Affiliation(s)
- Qian-Qian Pang
- State Key Laboratory of Bioactive Molecules and Druggability Assessment; Guangdong Province Key Laboratory of Pharmacodynamic Constituents of TCM and New Drugs Research; Institute of Traditional Chinese Medicine & Natural Products, College of Pharmacy; Jinan University, Guangzhou, 510632, People's Republic of China; University of Michigan Life Sciences Institute, Ann Arbor, MI 48109-2216, United States
| | - Cai-Xia Zang
- Institute of Materia Medica, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing 100050, People's Republic of China
| | - Ting Li
- State Key Laboratory of Bioactive Molecules and Druggability Assessment; Guangdong Province Key Laboratory of Pharmacodynamic Constituents of TCM and New Drugs Research; Institute of Traditional Chinese Medicine & Natural Products, College of Pharmacy; Jinan University, Guangzhou, 510632, People's Republic of China
| | - Xiao-Chun Zeng
- State Key Laboratory of Bioactive Molecules and Druggability Assessment; Guangdong Province Key Laboratory of Pharmacodynamic Constituents of TCM and New Drugs Research; Institute of Traditional Chinese Medicine & Natural Products, College of Pharmacy; Jinan University, Guangzhou, 510632, People's Republic of China
| | - Ling-Xian Liu
- State Key Laboratory of Bioactive Molecules and Druggability Assessment; Guangdong Province Key Laboratory of Pharmacodynamic Constituents of TCM and New Drugs Research; Institute of Traditional Chinese Medicine & Natural Products, College of Pharmacy; Jinan University, Guangzhou, 510632, People's Republic of China
| | - Dan Zhang
- Institute of Materia Medica, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing 100050, People's Republic of China.
| | - Xin-Sheng Yao
- State Key Laboratory of Bioactive Molecules and Druggability Assessment; Guangdong Province Key Laboratory of Pharmacodynamic Constituents of TCM and New Drugs Research; Institute of Traditional Chinese Medicine & Natural Products, College of Pharmacy; Jinan University, Guangzhou, 510632, People's Republic of China.
| | - Yang Yu
- State Key Laboratory of Bioactive Molecules and Druggability Assessment; Guangdong Province Key Laboratory of Pharmacodynamic Constituents of TCM and New Drugs Research; Institute of Traditional Chinese Medicine & Natural Products, College of Pharmacy; Jinan University, Guangzhou, 510632, People's Republic of China.
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Mi Z, Povysheva N, Rose ME, Ma J, Zeh DJ, Harikumar N, Bhuiyan MIH, Graham SH. Abolishing UCHL1's hydrolase activity exacerbates ischemia-induced axonal injury and functional deficits in mice. J Cereb Blood Flow Metab 2024:271678X241258809. [PMID: 38833565 DOI: 10.1177/0271678x241258809] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 06/06/2024]
Abstract
Ubiquitin C-terminal hydrolase L1 (UCHL1) is a neuronal protein important in maintaining axonal integrity and motor function and may be important in the pathogenesis of many neurological disorders. UCHL1 may ameliorate acute injury and improve recovery after cerebral ischemia. In the current study, the hypothesis that UCHL1's hydrolase activity underlies its effect in maintaining axonal integrity and function is tested after ischemic injury. Hydrolase activity was inhibited by treatment with a UCHL1 hydrolase inhibitor or by employing knockin mice bearing a mutation in the hydrolase active site (C90A). Ischemic injury was induced by oxygen-glucose deprivation (OGD) in brain slice preparations and by transient middle cerebral artery occlusion (tMCAO) surgery in mice. Hydrolase activity inhibition increased restoration time and decreased the amplitude of evoked axonal responses in the corpus callosum after OGD. Mutation of the hydrolase active site exacerbated white matter injury as detected by SMI32 immunohistochemistry, and motor deficits as detected by beam balance and cylinder testing after tMCAO. These results demonstrate that UCHL1 hydrolase activity ameliorates white matter injury and functional deficits after acute ischemic injury and support the hypothesis that UCHL1 activity plays a significant role in preserving white matter integrity and recovery of function after cerebral ischemia.
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Affiliation(s)
- Zhiping Mi
- Department of Neurology, School of Medicine, Kenneth P. Dietrich School of Arts and Sciences, University of Pittsburgh, Pittsburgh, PA, USA
| | - Nadya Povysheva
- Department of Neuroscience, Kenneth P. Dietrich School of Arts and Sciences, University of Pittsburgh, Pittsburgh, PA, USA
| | - Marie E Rose
- Department of Neurology, School of Medicine, Kenneth P. Dietrich School of Arts and Sciences, University of Pittsburgh, Pittsburgh, PA, USA
| | - Jie Ma
- Department of Neurology, School of Medicine, Kenneth P. Dietrich School of Arts and Sciences, University of Pittsburgh, Pittsburgh, PA, USA
| | - Dennis J Zeh
- Department of Neurology, School of Medicine, Kenneth P. Dietrich School of Arts and Sciences, University of Pittsburgh, Pittsburgh, PA, USA
| | - Nikitha Harikumar
- Department of Neuroscience, Kenneth P. Dietrich School of Arts and Sciences, University of Pittsburgh, Pittsburgh, PA, USA
| | - Mohammad Iqbal H Bhuiyan
- Department of Pharmaceutical Sciences, School of Pharmacy, University of Texas at El Paso, El Paso, TX, USA
| | - Steven H Graham
- Department of Neurology, School of Medicine, Kenneth P. Dietrich School of Arts and Sciences, University of Pittsburgh, Pittsburgh, PA, USA
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Zerimech S, Nguyen H, Vandenbark AA, Offner H, Baltan S. Novel therapeutic for multiple sclerosis protects white matter function in EAE mouse model. FRONTIERS IN MOLECULAR MEDICINE 2023; 3:1237078. [PMID: 37933270 PMCID: PMC10627517 DOI: 10.3389/fmmed.2023.1237078] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Indexed: 11/08/2023]
Abstract
Multiple sclerosis (MS) is a chronic demyelinating disease with prominent axon dysfunction. Our previous studies in an MS mouse model, experimental autoimmune encephalomyelitis (EAE), demonstrated that major histocompatibility complex Class II constructs can reverse clinical signs of EAE. These constructs block binding and downstream signaling of macrophage migration inhibitory factors (MIF-1/2) through CD74, thereby inhibiting phosphorylation of extracellular signal-regulated kinase (ERK) activation and tissue inflammation and promoting remyelination. To directly assess the effects of a novel third generation construct, DRhQ, on axon integrity in EAE, we compared axon conduction properties using electrophysiology on corpus callosum slices and optic nerves. By using two distinct white matter (WM) tracts, we aimed to assess the impact of the EAE and the benefit of DRhQ on myelinated and unmyelinated axons as well as to test the clinical value of DRhQ on demyelinating lesions in CC and optic myelitis. Our study found that EAE altered axon excitability, delayed axon conduction and slowed spatiotemporal summation correlated with diffuse astrocyte and microglia activation. Because MS predisposes patients to stroke, we also investigated and showed that vulnerability to WM ischemia is increased in the EAE MS mouse model. Treatment with DRhQ after the onset of EAE drastically inhibited microglial and astrocyte activation, improved functional integrity of the myelinated axons and enhanced recovery after ischemia. These results demonstrate that DRhQ administered after the onset of EAE promotes WM integrity and function, and reduces subsequent vulnerability to ischemic injury, suggesting important therapeutic potential for treatment of progressive MS.
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Affiliation(s)
- Sarah Zerimech
- Anesthesiology and Perioperative Medicine (APOM), Oregon Health and Science University, Portland, OR, United States
| | - Hung Nguyen
- Anesthesiology and Perioperative Medicine (APOM), Oregon Health and Science University, Portland, OR, United States
| | - Arthur A. Vandenbark
- Neuroimmunology Research, VA Portland Healthcare System, Portland, OR, United States
- Department of Neurology, Oregon Health and Science University, Portland, OR, United States
- Department of Molecular Microbiology and Immunology, Oregon Health and Science University, Portland, OR, United States
| | - Halina Offner
- Anesthesiology and Perioperative Medicine (APOM), Oregon Health and Science University, Portland, OR, United States
- Neuroimmunology Research, VA Portland Healthcare System, Portland, OR, United States
- Department of Neurology, Oregon Health and Science University, Portland, OR, United States
| | - Selva Baltan
- Anesthesiology and Perioperative Medicine (APOM), Oregon Health and Science University, Portland, OR, United States
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Bastian C, Zerimech S, Nguyen H, Doherty C, Franke C, Faris A, Quinn J, Baltan S. Aging astrocytes metabolically support aging axon function by proficiently regulating astrocyte-neuron lactate shuttle. Exp Neurol 2022; 357:114173. [PMID: 35863500 PMCID: PMC11218845 DOI: 10.1016/j.expneurol.2022.114173] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2022] [Revised: 06/23/2022] [Accepted: 07/14/2022] [Indexed: 11/19/2022]
Abstract
The astrocyte-neuron lactate shuttle (ANLS) is an essential metabolic support system that uptakes glucose, stores it as glycogen in astrocytes, and provides glycogen-derived lactate for axonal function. Aging intrinsically increases the vulnerability of white matter (WM) to injury. Therefore, we investigated the regulation of this shuttle to understand vascular-glial metabolic coupling to support axonal function during aging in two different WM tracts. Aging astrocytes displayed larger cell bodies and thicker horizontal processes in contrast to thinner vertically oriented processes of young astrocytes. Aging axons recovered less following aglycemia in mouse optic nerves (MONs) compared to young axons, although providing lactate during aglycemia equally supported young and aging axonal function. Incubating MONs in high glucose to upregulate glycogen stores in astrocytes delayed loss of function during aglycemia and improved recovery in both young and aging axons. Providing lactate during recovery from aglycemia unmasked a metabolic switch from glucose to lactate in aging axons. Young and aging corpus callosum consisting of a mixture of myelinated and unmyelinated axons sustained their function fully when lactate was available during aglycemia and surprisingly showed a greater resilience to aglycemia compared to fully myelinated axons of optic nerve. We conclude that lactate is a universal substrate for axons independent of their myelination content and age.
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Affiliation(s)
- Chinthasagar Bastian
- Department of Neurosciences, Cleveland Clinic Foundation, Cleveland, OH 441952, United States of America
| | - Sarah Zerimech
- Anesthesia and Perioperative Medicine, Oregon Health and Science University, Portland, OR 97239, United States of America
| | - Hung Nguyen
- Anesthesia and Perioperative Medicine, Oregon Health and Science University, Portland, OR 97239, United States of America
| | - Christine Doherty
- Department of Neurosciences, Cleveland Clinic Foundation, Cleveland, OH 441952, United States of America
| | - Caroline Franke
- Department of Neurosciences, Cleveland Clinic Foundation, Cleveland, OH 441952, United States of America
| | - Anna Faris
- Department of Neurosciences, Cleveland Clinic Foundation, Cleveland, OH 441952, United States of America
| | - John Quinn
- Department of Neurosciences, Cleveland Clinic Foundation, Cleveland, OH 441952, United States of America
| | - Selva Baltan
- Anesthesia and Perioperative Medicine, Oregon Health and Science University, Portland, OR 97239, United States of America; Department of Neurosciences, Cleveland Clinic Foundation, Cleveland, OH 441952, United States of America.
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Nguyen H, Zhu W, Baltan S. Casein Kinase 2 Signaling in White Matter Stroke. Front Mol Biosci 2022; 9:908521. [PMID: 35911974 PMCID: PMC9325966 DOI: 10.3389/fmolb.2022.908521] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2022] [Accepted: 06/21/2022] [Indexed: 11/27/2022] Open
Abstract
The growth of the aging population, together with improved stroke care, has resulted in an increase in stroke survivors and a rise in recurrent events. Axonal injury and white matter (WM) dysfunction are responsible for much of the disability observed after stroke. The mechanisms of WM injury are distinct compared to gray matter and change with age. Therefore, an ideal stroke therapeutic must restore neuronal and axonal function when applied before or after a stroke, and it must also protect across age groups. Casein kinase 2 (CK2), is expressed in the brain, including WM, and is regulated during the development and numerous disease conditions such as cancer and ischemia. CK2 activation in WM mediates ischemic injury by activating the Cdk5 and AKT/GSK3β signaling pathways. Consequently, CK2 inhibition using the small molecule inhibitor CX-4945 (Silmitasertib) correlates with preservation of oligodendrocytes, conservation of axon structure, and axonal mitochondria, leading to improved functional recovery. Remarkably, CK2 inhibition promotes WM function when applied after ischemic injury by specifically regulating the AKT/GSK3β pathways. The blockade of the active conformation of AKT confers post-ischemic protection to young and old WM by preserving mitochondria, implying AKT as a common therapeutic target across age groups. Using a NanoString nCounter miRNA expression profiling, comparative analyses of ischemic WM with or without CX-4945 treatment reveal that miRNAs are expressed at high levels in WM after ischemia, and CX-4945 differentially regulates some of these miRNAs. Therefore, we propose that miRNA regulation may be one of the protective actions of CX-4945 against WM ischemic injury. Silmitasertib is FDA approved and currently in use for cancer and Covid patients; therefore, it is plausible to repurpose CK2 inhibitors for stroke patients.
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Affiliation(s)
| | | | - Selva Baltan
- Anesthesiology and Peri-Operative Medicine (APOM), Oregon Health and Science University, Portland, OR, United States
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Ransom BR, Goldberg MP, Arai K, Baltan S. White Matter Pathophysiology. Stroke 2022. [DOI: 10.1016/b978-0-323-69424-7.00009-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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Hamner MA, McDonough A, Gong DC, Todd LJ, Rojas G, Hodecker S, Ransom CB, Reh TA, Ransom BR, Weinstein JR. Microglial depletion abolishes ischemic preconditioning in white matter. Glia 2021; 70:661-674. [PMID: 34939240 DOI: 10.1002/glia.24132] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2021] [Revised: 12/10/2021] [Accepted: 12/10/2021] [Indexed: 01/17/2023]
Abstract
Ischemic preconditioning (IPC) is a phenomenon whereby a brief, non-injurious ischemic exposure enhances tolerance to a subsequent ischemic challenge. The mechanism of IPC has mainly been studied in rodent stroke models where gray matter (GM) constitutes about 85% of the cerebrum. In humans, white matter (WM) is 50% of cerebral volume and is a critical component of stroke damage. We developed a novel CNS WM IPC model using the mouse optic nerve (MON) and identified the involved immune signaling pathways. Here we tested the hypothesis that microglia are necessary for WM IPC. Microglia were depleted by treatment with the colony stimulating factor 1 receptor (CSF1R) inhibitor PLX5622. MONs were exposed to transient ischemia in vivo, acutely isolated 72 h later, and subjected to oxygen-glucose deprivation (OGD) to simulate a severe ischemic injury (i.e., stroke). Functional and structural axonal recovery was assessed by recording compound action potentials (CAPs) and by microscopy using quantitative stereology. Microglia depletion eliminated IPC-mediated protection. In control mice, CAP recovery was improved in preconditioned MONs compared with non-preconditioned MONs, however, in PLX5622-treated mice, we observed no difference in CAP recovery between preconditioned and non-preconditioned MONs. Microgliadepletion also abolished IPC protective effects on axonal integrity and survival of mature (APC+ ) oligodendrocytes after OGD. IPC-mediated protection was independent of retinal injury suggesting it results from mechanistic processes intrinsic to ischemia-exposed WM. We conclude that preconditioned microglia are critical for IPC in WM. The "preconditioned microglia" phenotype might protect against other CNS pathologies and is a neurotherapeutic horizon worth exploring.
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Affiliation(s)
- Margaret A Hamner
- Department of Neurology, School of Medicine, University of Washington, Seattle, Washington, USA
| | - Ashley McDonough
- Department of Neurology, School of Medicine, University of Washington, Seattle, Washington, USA
| | - Davin C Gong
- Department of Neurology, School of Medicine, University of Washington, Seattle, Washington, USA
| | - Levi J Todd
- Department of Biological Structure, School of Medicine, University of Washington, Seattle, Washington, USA
| | - German Rojas
- Department of Neurology, School of Medicine, University of Washington, Seattle, Washington, USA
| | - Sibylle Hodecker
- Department of Neurology, School of Medicine, University of Washington, Seattle, Washington, USA
| | - Christopher B Ransom
- Department of Neurology, School of Medicine, University of Washington, Seattle, Washington, USA
| | - Thomas A Reh
- Department of Biological Structure, School of Medicine, University of Washington, Seattle, Washington, USA
| | - Bruce R Ransom
- Department of Neurology, School of Medicine, University of Washington, Seattle, Washington, USA.,Neuroscience Department, City University of Hong Kong, Kowloon, Hong Kong
| | - Jonathan R Weinstein
- Department of Neurology, School of Medicine, University of Washington, Seattle, Washington, USA.,Department of Neurological Surgery, School of Medicine, University of Washington, Seattle, Washington, USA
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Fairless R, Bading H, Diem R. Pathophysiological Ionotropic Glutamate Signalling in Neuroinflammatory Disease as a Therapeutic Target. Front Neurosci 2021; 15:741280. [PMID: 34744612 PMCID: PMC8567076 DOI: 10.3389/fnins.2021.741280] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2021] [Accepted: 09/30/2021] [Indexed: 01/15/2023] Open
Abstract
Glutamate signalling is an essential aspect of neuronal communication involving many different glutamate receptors, and underlies the processes of memory, learning and synaptic plasticity. Despite neuroinflammatory diseases covering a range of maladies with very different biological causes and pathophysiologies, a central role for dysfunctional glutamate signalling is becoming apparent. This is not just restricted to the well-described role of glutamate in mediating neurodegeneration, but also includes a myriad of other influences that glutamate can exert on the vasculature, as well as immune cell and glial regulation, reflecting the ability of neurons to communicate with these compartments in order to couple their activity with neuronal requirements. Here, we discuss the role of pathophysiological glutamate signalling in neuroinflammatory disease, using both multiple sclerosis and Alzheimer's disease as examples, and how current steps are being made to harness our growing understanding of these processes in the development of neuroprotective strategies. This review focuses in particular on N-methyl-D-aspartate (NMDA) and 2-amino-3-(3-hydroxy-5-methylisooxazol-4-yl) propionate (AMPA) type ionotropic glutamate receptors, although metabotropic, G-protein-coupled glutamate receptors may also contribute to neuroinflammatory processes. Given the indispensable roles of glutamate-gated ion channels in synaptic communication, means of pharmacologically distinguishing between physiological and pathophysiological actions of glutamate will be discussed that allow deleterious signalling to be inhibited whilst minimising the disturbance of essential neuronal function.
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Affiliation(s)
- Richard Fairless
- Department of Neurology, University Clinic Heidelberg, Heidelberg, Germany.,Clinical Cooperation Unit (CCU) Neurooncology, German Cancer Consortium (DKTK), German Cancer Research Center (DKFZ), Heidelberg, Germany
| | - Hilmar Bading
- Department of Neurobiology, Interdisciplinary Center for Neurosciences, Heidelberg University, Heidelberg, Germany
| | - Ricarda Diem
- Department of Neurology, University Clinic Heidelberg, Heidelberg, Germany.,Clinical Cooperation Unit (CCU) Neurooncology, German Cancer Consortium (DKTK), German Cancer Research Center (DKFZ), Heidelberg, Germany
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Baltan S, Sandau US, Brunet S, Bastian C, Tripathi A, Nguyen H, Liu H, Saugstad JA, Zarnegarnia Y, Dutta R. Identification of miRNAs That Mediate Protective Functions of Anti-Cancer Drugs During White Matter Ischemic Injury. ASN Neuro 2021; 13:17590914211042220. [PMID: 34619990 PMCID: PMC8642107 DOI: 10.1177/17590914211042220] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
We have previously shown that two anti-cancer drugs, CX-4945 and MS-275, protect and preserve white matter (WM) architecture and improve functional recovery in a model of WM ischemic injury. While both compounds promote recovery, CX-4945 is a selective Casein kinase 2 (CK2) inhibitor and MS-275 is a selective Class I histone deacetylase (HDAC) inhibitor. Alterations in microRNAs (miRNAs) mediate some of the protective actions of these drugs. In this study, we aimed to (1) identify miRNAs expressed in mouse optic nerves (MONs); (2) determine which miRNAs are regulated by oxygen glucose deprivation (OGD); and (3) determine the effects of CX-4945 and MS-275 treatment on miRNA expression. RNA isolated from MONs from control and OGD-treated animals with and without CX-4945 or MS-275 treatment were quantified using NanoString nCounter® miRNA expression profiling. Comparative analysis of experimental groups revealed that 12 miRNAs were expressed at high levels in MONs. OGD upregulated five miRNAs (miR-1959, miR-501-3p, miR-146b, miR-201, and miR-335-3p) and downregulated two miRNAs (miR-1937a and miR-1937b) compared to controls. OGD with CX-4945 upregulated miR-1937a and miR-1937b, and downregulated miR-501-3p, miR-200a, miR-1959, and miR-654-3p compared to OGD alone. OGD with MS-275 upregulated miR-2134, miR-2141, miR-2133, miR-34b-5p, miR-153, miR-487b, miR-376b, and downregulated miR-717, miR-190, miR-27a, miR-1959, miR-200a, miR-501-3p, and miR-200c compared to OGD alone. Interestingly, miR-501-3p and miR-1959 were the only miRNAs upregulated by OGD, and downregulated by OGD plus CX-4945 and MS-275. Therefore, we suggest that protective functions of CX-4945 or MS-275 against WM injury maybe mediated, in part, through miRNA expression.
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Affiliation(s)
- Selva Baltan
- Anesthesiology and Perioperative Medicine, Oregon Health and Science University, Portland, OR 97239, USA
- Department of Neurosciences, Cleveland Clinic Foundation, Cleveland, OH 44195, USA
- Selva Baltan, Anesthesiology and Perioperative Medicine, Oregon Health and Science University, Mackenzie Hall 2140A, L459, 3181 S.W. Sam Jackson Park Rd., Portland, OR 97239, USA.
| | - Ursula S. Sandau
- Anesthesiology and Perioperative Medicine, Oregon Health and Science University, Portland, OR 97239, USA
| | - Sylvain Brunet
- Department of Neurosciences, Cleveland Clinic Foundation, Cleveland, OH 44195, USA
| | - Chinthasagar Bastian
- Department of Neurosciences, Cleveland Clinic Foundation, Cleveland, OH 44195, USA
| | - Ajai Tripathi
- Department of Neurosciences, Cleveland Clinic Foundation, Cleveland, OH 44195, USA
| | - Hung Nguyen
- Anesthesiology and Perioperative Medicine, Oregon Health and Science University, Portland, OR 97239, USA
| | - Helen Liu
- Anesthesiology and Perioperative Medicine, Oregon Health and Science University, Portland, OR 97239, USA
| | - Julie A. Saugstad
- Anesthesiology and Perioperative Medicine, Oregon Health and Science University, Portland, OR 97239, USA
| | - Yalda Zarnegarnia
- Anesthesiology and Perioperative Medicine, Oregon Health and Science University, Portland, OR 97239, USA
| | - Ranjan Dutta
- Department of Neurosciences, Cleveland Clinic Foundation, Cleveland, OH 44195, USA
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Nguyen H, Zerimech S, Baltan S. Astrocyte Mitochondria in White-Matter Injury. Neurochem Res 2021; 46:2696-2714. [PMID: 33527218 PMCID: PMC8935665 DOI: 10.1007/s11064-021-03239-8] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2020] [Revised: 01/05/2021] [Accepted: 01/06/2021] [Indexed: 12/11/2022]
Abstract
This review summarizes the diverse structure and function of astrocytes to describe the bioenergetic versatility required of astrocytes that are situated at different locations. The intercellular domain of astrocyte mitochondria defines their roles in supporting and regulating astrocyte-neuron coupling and survival against ischemia. The heterogeneity of astrocyte mitochondria, and how subpopulations of astrocyte mitochondria adapt to interact with other glia and regulate axon function, require further investigation. It has become clear that mitochondrial permeability transition pores play a key role in a wide variety of human diseases, whose common pathology may be based on mitochondrial dysfunction triggered by Ca2+ and potentiated by oxidative stress. Reactive oxygen species cause axonal degeneration and a reduction in axonal transport, leading to axonal dystrophies and neurodegeneration including Alzheimer's disease, amyotrophic lateral sclerosis, Parkinson's disease, and Huntington's disease. Developing new tools to allow better investigation of mitochondrial structure and function in astrocytes, and techniques to specifically target astrocyte mitochondria, can help to unravel the role of mitochondrial health and dysfunction in a more inclusive context outside of neuronal cells. Overall, this review will assess the value of astrocyte mitochondria as a therapeutic target to mitigate acute and chronic injury in the CNS.
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Affiliation(s)
- Hung Nguyen
- Anesthesiology and Peri-Operative Medicine (APOM), Oregon Health and Science University, Portland, OR, 97239, USA
| | - Sarah Zerimech
- Anesthesiology and Peri-Operative Medicine (APOM), Oregon Health and Science University, Portland, OR, 97239, USA
| | - Selva Baltan
- Anesthesiology and Peri-Operative Medicine (APOM), Oregon Health and Science University, Portland, OR, 97239, USA.
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Kahveci FO, Kahveci R, Gokce EC, Gokce A, Kısa Ü, Sargon MF, Fesli R, Sarı MF, Gürer B. Biochemical, pathological and ultrastructural investigation of whether lamotrigine has neuroprotective efficacy against spinal cord ischemia reperfusion injury. Injury 2021; 52:2803-2812. [PMID: 34391576 DOI: 10.1016/j.injury.2021.08.004] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/05/2021] [Revised: 07/26/2021] [Accepted: 08/02/2021] [Indexed: 02/02/2023]
Abstract
INTRODUCTION Lamotrigine, an anticonvulsant drug with inhibition properties of multi-ion channels, has been shown to be able to attenuates secondary neuronal damage by influencing different pathways. The aim of this study was to look into whether lamotrigine treatment could protect the spinal cord from experimental spinal cord ischemia-reperfusion injury. MATERIALS AND METHODS Thirty-two rats, eight rats per group, were randomly assigned to the sham group in which only laparotomy was performed, and to the ischemia, methylprednisolone and lamotrigine groups, where the infrarenal aorta was clamped for thirty minutes to induce spinal cord ischemia-reperfusion injury. Tissue samples belonging to spinal cords were harvested from sacrificed animals twenty-four hours after reperfusion. Tumor necrosis factor-alpha levels, interleukin-1 beta levels, nitric oxide levels, superoxide dismutase activity, catalase activity, glutathione peroxidase activity, malondialdehyde levels and caspase-3 activity were studied. Light and electron microscopic evaluations were also performed to reveal the pathological alterations. Basso, Beattie, and Bresnahan locomotor scale and the inclined-plane test was used to evaluate neurofunctional status at the beginning of the study and just before the animals were sacrificed. RESULTS Lamotrigine treatment provided significant improvement in the neurofunctional status by preventing the increase in cytokine expression, increased lipid peroxidation and oxidative stress, depletion of antioxidant enzymes activity and increased apoptosis, all of which contributing to spinal cord damage through different paths after ischemia reperfusion injury. Furthermore, lamotrigine treatment has shown improved results concerning the histopathological and ultrastructural scores and the functional tests. CONCLUSION These results proposed that lamotrigine may be a useful therapeutic agent to prevent the neuronal damage developing after spinal cord ischemia-reperfusion injury.
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Affiliation(s)
- Fatih Ozan Kahveci
- Department of Emergency Medicine, Balıkesir Atatürk City Hospital, Balıkesir, Turkey
| | - Ramazan Kahveci
- Department of Neurosurgery, Balıkesir University, Faculty of Medicine, Balıkesir, Turkey
| | - Emre Cemal Gokce
- Department of Neurosurgery, Abdurrahman Yurtaslan Ankara Oncology Education and Research Hospital, Ankara, Turkey
| | - Aysun Gokce
- Department of Pathology, Ministry of Health, Diskapi Yildirim Beyazit Education and Research Hospital, Ankara, Turkey
| | - Üçler Kısa
- Department of Biochemistry, Kirikkale University, Faculty of Medicine, Kirikkale, Turkey
| | - Mustafa Fevzi Sargon
- Department of Anatomy, Lokman Hekim University, Faculty of Medicine, Ankara, Turkey
| | - Ramazan Fesli
- Department of Neurosurgery, Mersin VM Medical Park Hospital, Mersin, Turkey
| | - Muhammed Fatih Sarı
- Department of Neurosurgery, Balıkesir University, Faculty of Medicine, Balıkesir, Turkey
| | - Bora Gürer
- Department of Neurosurgery, İstinye University, Faculty of Medicine, Istanbul, Turkey.
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12
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Lajoso W, Flower G, Giacco V, Kaul A, La Mache C, Brăban A, Roxas A, Hamilton NB. Transient Receptor Potential Ankyrin-1 (TRPA1) Block Protects against Loss of White Matter Function during Ischaemia in the Mouse Optic Nerve. Pharmaceuticals (Basel) 2021; 14:ph14090909. [PMID: 34577609 PMCID: PMC8469017 DOI: 10.3390/ph14090909] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2021] [Revised: 09/02/2021] [Accepted: 09/03/2021] [Indexed: 11/28/2022] Open
Abstract
Oligodendrocytes produce myelin, which provides insulation to axons and speeds up neuronal transmission. In ischaemic conditions, myelin is damaged, resulting in mental and physical disabilities. Recent evidence suggests that oligodendrocyte damage during ischaemia can be mediated by Transient Receptor Potential Ankyrin-1 (TRPA1), whose activation raises intracellular Ca2+ concentrations and damages compact myelin. Here, we show that TRPA1 is constitutively active in oligodendrocytes and the optic nerve, as the specific TRPA1 antagonist, A-967079, decreases basal oligodendrocyte Ca2+ concentrations and increases the size of the compound action potential (CAP). Conversely, TRPA1 agonists reduce the size of the optic nerve CAP in an A-967079-sensitive manner. These results indicate that glial TRPA1 regulates neuronal excitability in the white matter under physiological as well as pathological conditions. Importantly, we find that inhibition of TRPA1 prevents loss of CAPs during oxygen and glucose deprivation (OGD) and improves the recovery. TRPA1 block was effective when applied before, during, or after OGD, indicating that the TRPA1-mediated damage is occurring during both ischaemia and recovery, but importantly, that therapeutic intervention is possible after the ischaemic insult. These results indicate that TRPA1 has an important role in the brain, and that its block may be effective in treating many white matter diseases.
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13
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Roth LM, Akay-Espinoza C, Grinspan JB, Jordan-Sciutto KL. HIV-induced neuroinflammation inhibits oligodendrocyte maturation via glutamate-dependent activation of the PERK arm of the integrated stress response. Glia 2021; 69:2252-2271. [PMID: 34058792 DOI: 10.1002/glia.24033] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2021] [Revised: 05/14/2021] [Accepted: 05/17/2021] [Indexed: 12/15/2022]
Abstract
Despite combined antiretroviral therapy (cART), HIV-associated neurocognitive disorder (HAND) affects 30-50% of HIV-positive patients. Importantly, persistent white matter pathologies, specifically corpus callosum thinning and disruption of white matter microstructures observed in patients with HAND despite viral control through cART, raise the possibility that HIV infection in the setting of suboptimal cART may perturb oligodendrocyte (OL) maturation, function and/or survival, influencing HAND persistence in the cART era. To examine the effect of HIV infection on OL maturation, we used supernatants of primary human monocyte-derived macrophages infected with HIV (HIV/MDMs) to treat primary cultures of rat oligodendrocyte precursor cells (OPCs) during their differentiation to mature OLs. Using immunostaining for lineage-specific markers, we found that HIV/MDMs significantly inhibited OPC maturation. Based on our previous studies, we examined the potential role of several signaling pathways, including ionotropic glutamate receptors and the integrated stress response (ISR), and found that AMPA receptors (AMPAR)/kainic acid (KA) receptors (KARs) mediated the HIV/MDMs-induced defect in OL maturation. We also found that the treatment of OPC cultures with glutamate or AMPAR/KAR agonists phenocopied this effect. Blocking ISR activation, specifically the PERK arm of the ISR, protected OPCs from HIV/MDMs-mediated inhibition of OL maturation. Further, while glutamate, AMPA, and KA activated the ISR, inhibition of AMPAR/KAR activation prevented ISR induction in OPCs and rescued OL maturation. Collectively, these data identify glutamate signaling via ISR activation as a potential therapeutic pathway to ameliorate white matter pathologies in HAND and highlight the need for further investigation of their contribution to cognitive impairment.
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Affiliation(s)
- Lindsay M Roth
- Department of Basic and Translational Sciences, School of Dental Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, USA.,Department of Neurology, The Children's Hospital of Philadelphia, Philadelphia, Pennsylvania, USA
| | - Cagla Akay-Espinoza
- Department of Basic and Translational Sciences, School of Dental Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - Judith B Grinspan
- Department of Neurology, The Children's Hospital of Philadelphia, Philadelphia, Pennsylvania, USA
| | - Kelly L Jordan-Sciutto
- Department of Basic and Translational Sciences, School of Dental Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, USA
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14
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Li F, Song X, Xu J, Shi Y, Hu R, Ren Z, Qi Q, Lü H, Cheng X, Hu J. Morroniside protects OLN-93 cells against H 2O 2-induced injury through the PI3K/Akt pathway-mediated antioxidative stress and antiapoptotic activities. Cell Cycle 2021; 20:661-675. [PMID: 33734020 DOI: 10.1080/15384101.2021.1889186] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
Neurodegenerative disorders, including spinal cord injury (SCI), result in oxidative stress-induced cell damage. Morroniside (MR), a major active ingredient of the Chinese herb Shan Zhu Yu, has been shown to ameliorate oxidative stress and inflammatory response. Our previous study also confirmed that morroniside protects SK-N-SH cell line (human neuroblastoma cells) against oxidative impairment. However, it remains unclear whether MR also plays a protective role for oligodendrocytes that are damaged following SCI. The present study investigated the protective effects of MR against hydrogen peroxide (H2O2)-induced cell death in OLN-93 cells. MR protected OLN-93 cells from H2O2-induced injury, attenuated H2O2-induced increase in reactive oxygen species (ROS) and malondialdehyde (MDA) levels, and blocked the reduction of mitochondrial membrane potential (MMP) induced by H2O2. MR enhanced the activity of the antioxidant enzyme superoxide dismutase (SOD) and suppressed H2O2-induced downregulation of the antiapoptotic protein Bcl-2 and activation of the proapoptotic protein caspase-3. Finally, we found that LY294002, a specific inhibitor of the PI3K/Akt pathway, inhibited the protective effect of MR against H2O2-induced OLN-93 cell injury in the MTT and TUNEL assays. LY294002 also inhibited the expression of SOD and Bcl-2, and increased the expression of iNOS and c-caspase-3 induced by MR treatment. MR exerts protective effects against H2O2-induced OLN-93 cell injury through the PI3K/Akt signaling pathway-mediated antioxidative stress and antiapoptotic activities. MR may provide a potential strategy for SCI treatment or other related neurodegeneration.
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Affiliation(s)
- Fengzhi Li
- Department of Cell Biology College of Basic Medical Sciences, Dalian Medical University, Dalian, P.R. China
| | - Xue Song
- Department of Central Laboratory, The First Affiliated Hospital of Bengbu Medical College, Bengbu, P.R. China.,Department of Clinical Laboratory, The First Affiliated Hospital of Bengbu Medical College, Bengbu, P.R. China
| | - Jiaxin Xu
- Department of Cell Biology College of Basic Medical Sciences, Dalian Medical University, Dalian, P.R. China
| | - Yujiao Shi
- Department of Clinical Laboratory, The First Affiliated Hospital of Bengbu Medical College, Bengbu, P.R. China.,Anhui Key Laboratory of Tissue Transplantation, Bengbu Medical College, Bengbu, P.R. China
| | - Ruina Hu
- Department of Cell Biology College of Basic Medical Sciences, Dalian Medical University, Dalian, P.R. China
| | - Zhen Ren
- Department of Cell Biology College of Basic Medical Sciences, Dalian Medical University, Dalian, P.R. China
| | - Qi Qi
- Anhui Key Laboratory of Tissue Transplantation, Bengbu Medical College, Bengbu, P.R. China
| | - Hezuo Lü
- Department of Clinical Laboratory, The First Affiliated Hospital of Bengbu Medical College, Bengbu, P.R. China.,Anhui Key Laboratory of Tissue Transplantation, Bengbu Medical College, Bengbu, P.R. China
| | - Xiaoxin Cheng
- Department of Cell Biology College of Basic Medical Sciences, Dalian Medical University, Dalian, P.R. China
| | - Jianguo Hu
- Department of Clinical Laboratory, The First Affiliated Hospital of Bengbu Medical College, Bengbu, P.R. China.,Anhui Key Laboratory of Tissue Transplantation, Bengbu Medical College, Bengbu, P.R. China
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15
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Cui Y, Jin X, Choi JY, Kim BG. Modeling subcortical ischemic white matter injury in rodents: unmet need for a breakthrough in translational research. Neural Regen Res 2021; 16:638-642. [PMID: 33063714 PMCID: PMC8067929 DOI: 10.4103/1673-5374.295313] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022] Open
Abstract
Subcortical ischemic white matter injury (SIWMI), pathological correlate of white matter hyperintensities or leukoaraiosis on magnetic resonance imaging, is a common cause of cognitive decline in elderly. Despite its high prevalence, it remains unknown how various components of the white matter degenerate in response to chronic ischemia.This incomplete knowledge is in part due to a lack of adequate animal model. The current review introduces various SIWMI animal models and aims to scrutinize their advantages and disadvantages primarily in regard to the pathological manifestations of white matter components. The SIWMI animal models are categorized into 1) chemically induced SIWMI models, 2) vascular occlusive SIWMI models, and 3) SIWMI models with comorbid vascular risk factors. Chemically induced models display consistent lesions in predetermined areas of the white matter, but the abrupt evolution of lesions does not appropriately reflect the progressive pathological processes in human white matter hyperintensities. Vascular occlusive SIWMI models often do not exhibit white matter lesions that are sufficiently unequivocal to be quantified. When combined with comorbid vascular risk factors (specifically hypertension), however, they can produce progressive and definitive white matter lesions including diffuse rarefaction, demyelination, loss of oligodendrocytes, and glial activation, which are by far the closest to those found in human white matter hyperintensities lesions. However, considerable surgical mortality and unpredictable natural deaths during a follow-up period would necessitate further refinements in these models. In the meantime, in vitro SIWMI models that recapitulate myelinated white matter track may be utilized to study molecular mechanisms of the ischemic white matter injury. Appropriate in vivo and in vitro SIWMI models will contribute in a complementary manner to making a breakthrough in developing effective treatment to prevent progression of white matter hyperintensities.
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Affiliation(s)
- Yuexian Cui
- Department of Brain Science, Ajou University School of Medicine; Neuroscience Graduate Program, Department of Biomedical Sciences, Ajou University Graduate School of Medicine, Suwon, Korea; Department of Neurology, Yanbian University Hospital, Yanji, Jilin Province, China
| | - Xuelian Jin
- Department of Brain Science, Ajou University School of Medicine; Neuroscience Graduate Program, Department of Biomedical Sciences, Ajou University Graduate School of Medicine, Suwon, Korea; Department of Nephrology, Suqian First Hospital, Suqian, Jiangsu Province, China
| | - Jun Young Choi
- Department of Brain Science, Ajou University School of Medicine; Neuroscience Graduate Program, Department of Biomedical Sciences, Ajou University Graduate School of Medicine; Department of Neurology, Ajou University School of Medicine, Suwon, Korea
| | - Byung Gon Kim
- Department of Brain Science, Ajou University School of Medicine; Neuroscience Graduate Program, Department of Biomedical Sciences, Ajou University Graduate School of Medicine; Department of Neurology, Ajou University School of Medicine, Suwon, Korea
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16
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Qiu H, Qian T, Wu T, Wang X, Zhu C, Chen C, Wang L. Umbilical cord blood cells for the treatment of preterm white matter injury: Potential effects and treatment options. J Neurosci Res 2020; 99:778-792. [PMID: 33207392 DOI: 10.1002/jnr.24751] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2020] [Revised: 10/20/2020] [Accepted: 10/21/2020] [Indexed: 12/31/2022]
Abstract
Preterm birth is a global public health problem. A large number of preterm infants survive with preterm white matter injury (PWMI), which leads to neurological deficits, and has multifaceted etiology, clinical course, monitoring, and outcomes. The principal upstream insults leading to PWMI initiation are hypoxia-ischemia and infection and/or inflammation and the key target cells are late oligodendrocyte precursor cells. Current PWMI treatments are mainly supportive, and thus have little effect in terms of protecting the immature brain or repairing injury to improve long-term outcomes. Umbilical cord blood (UCB) cells comprise abundant immunomodulatory and stem cells, which have the potential to reduce brain injury, mainly due to anti-inflammatory and immunomodulatory mechanisms, and also through their release of neurotrophic or growth factors to promote endogenous neurogenesis. In this review, we briefly summarize PWMI pathogenesis and pathophysiology, and the specific properties of different cell types in UCB. We further explore the potential mechanism by which UCB can be used to treat PWMI, and discuss the advantages of and potential issues related to UCB cell therapy. Finally, we suggest potential future studies of UCB cell therapy in preterm infants.
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Affiliation(s)
- Han Qiu
- Key Laboratory of Neonatal Diseases of Health Commission of the People's Republic of China, Shanghai, China.,Department of Neonatology, National Children's Medical Center/Children's Hospital of Fudan University, Shanghai, China
| | - Tianyang Qian
- Key Laboratory of Neonatal Diseases of Health Commission of the People's Republic of China, Shanghai, China.,Department of Neonatology, National Children's Medical Center/Children's Hospital of Fudan University, Shanghai, China
| | - Tong Wu
- Key Laboratory of Neonatal Diseases of Health Commission of the People's Republic of China, Shanghai, China.,Department of Neonatology, National Children's Medical Center/Children's Hospital of Fudan University, Shanghai, China
| | - Xiaoyang Wang
- Center of Perinatal Medicine and Health, Institute of Neuroscience and Physiology, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden.,Henan Key Laboratory of Child Brain Injury, Institute of Neuroscience and Third Affiliated Hospital, Zhengzhou University, Zhengzhou, China
| | - Changlian Zhu
- Center of Perinatal Medicine and Health, Institute of Neuroscience and Physiology, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden.,Henan Key Laboratory of Child Brain Injury, Institute of Neuroscience and Third Affiliated Hospital, Zhengzhou University, Zhengzhou, China
| | - Chao Chen
- Key Laboratory of Neonatal Diseases of Health Commission of the People's Republic of China, Shanghai, China.,Department of Neonatology, National Children's Medical Center/Children's Hospital of Fudan University, Shanghai, China
| | - Laishuan Wang
- Key Laboratory of Neonatal Diseases of Health Commission of the People's Republic of China, Shanghai, China.,Department of Neonatology, National Children's Medical Center/Children's Hospital of Fudan University, Shanghai, China
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17
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Choi DW. Excitotoxicity: Still Hammering the Ischemic Brain in 2020. Front Neurosci 2020; 14:579953. [PMID: 33192266 PMCID: PMC7649323 DOI: 10.3389/fnins.2020.579953] [Citation(s) in RCA: 91] [Impact Index Per Article: 22.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2020] [Accepted: 09/25/2020] [Indexed: 12/13/2022] Open
Abstract
Interest in excitotoxicity expanded following its implication in the pathogenesis of ischemic brain injury in the 1980s, but waned subsequent to the failure of N-methyl-D-aspartate (NMDA) antagonists in high profile clinical stroke trials. Nonetheless there has been steady progress in elucidating underlying mechanisms. This review will outline the historical path to current understandings of excitotoxicity in the ischemic brain, and suggest that this knowledge should be leveraged now to develop neuroprotective treatments for stroke.
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Affiliation(s)
- Dennis W Choi
- Department of Neurology, SUNY Stony Brook, Stony Brook, NY, United States
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18
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Guo Z, Fan C, Li T, Gesang L, Yin W, Wang N, Weng X, Gong Q, Zhang J, Wang J. Neural network correlates of high-altitude adaptive genetic variants in Tibetans: A pilot, exploratory study. Hum Brain Mapp 2020; 41:2406-2430. [PMID: 32128935 PMCID: PMC7267913 DOI: 10.1002/hbm.24954] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2019] [Revised: 01/16/2020] [Accepted: 02/09/2020] [Indexed: 02/05/2023] Open
Abstract
Although substantial progress has been made in the identification of genetic substrates underlying physiology, neuropsychology, and brain organization, the genotype–phenotype associations remain largely unknown in the context of high‐altitude (HA) adaptation. Here, we related HA adaptive genetic variants in three gene loci (EGLN1, EPAS1, and PPARA) to interindividual variance in a set of physiological characteristics, neuropsychological tests, and topological attributes of large‐scale structural and functional brain networks in 135 indigenous Tibetan highlanders. Analyses of individual HA adaptive single‐nucleotide polymorphisms (SNPs) revealed that specific SNPs selectively modulated physiological characteristics (erythrocyte level, ratio between forced expiratory volume in the first second to forced vital capacity, arterial oxygen saturation, and heart rate) and structural network centrality (the left anterior orbital gyrus) with no effects on neuropsychology or functional brain networks. Further analyses of genetic adaptive scores, which summarized the overall degree of genetic adaptation to HA, revealed significant correlations only with structural brain networks with respect to local interconnectivity of the whole networks, intermodule communication between the right frontal and parietal module and the left occipital module, nodal centrality in several frontal regions, and connectivity strength of a subnetwork predominantly involving in intramodule edges in the right temporal and occipital module. Moreover, the associations were dependent on gene loci, weight types, or topological scales. Together, these findings shed new light on genotype–phenotype interactions under HA hypoxia and have important implications for developing new strategies to optimize organism and tissue responses to chronic hypoxia induced by extreme environments or diseases.
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Affiliation(s)
- Zhiyue Guo
- Institute of Brain Diseases and Cognition, School of Medicine, Xiamen University, Xiamen, Fujian, China
| | - Cunxiu Fan
- Institute of Brain Diseases and Cognition, School of Medicine, Xiamen University, Xiamen, Fujian, China.,Department of Neurology, Shanghai Changhai Hospital, Navy Medical University, Shanghai, China
| | - Ting Li
- Institute of Brain Diseases and Cognition, School of Medicine, Xiamen University, Xiamen, Fujian, China
| | - Luobu Gesang
- Institute of High Altitude Medicine, Tibet Autonomous Region People's Hospital, Lhasa, Tibet Autonomous Region, China
| | - Wu Yin
- Department of Radiology, Tibet Autonomous Region People's Hospital, Lhasa, Tibet Autonomous Region, China
| | - Ningkai Wang
- Department of Psychology, Hangzhou Normal University, Hangzhou, China
| | - Xuchu Weng
- Guangdong Key Laboratory of Mental Health and Cognitive Science, Center for Studies of Psychological Application, South China Normal University, Institute for Brain Research and Rehabilitation, Guangzhou, China
| | - Qiyong Gong
- Huaxi Magnetic Resonance Research Center, West China Hospital, Sichuan University, Chengdu, China
| | - Jiaxing Zhang
- Institute of Brain Diseases and Cognition, School of Medicine, Xiamen University, Xiamen, Fujian, China
| | - Jinhui Wang
- Guangdong Key Laboratory of Mental Health and Cognitive Science, Center for Studies of Psychological Application, South China Normal University, Institute for Brain Research and Rehabilitation, Guangzhou, China
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19
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White Matter and Neuroprotection in Alzheimer's Dementia. Molecules 2020; 25:molecules25030503. [PMID: 31979414 PMCID: PMC7038211 DOI: 10.3390/molecules25030503] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2019] [Revised: 01/20/2020] [Accepted: 01/21/2020] [Indexed: 12/12/2022] Open
Abstract
Myelin is the main component of the white matter of the central nervous system (CNS), allowing the proper electrical function of the neurons by ensheathing and insulating the axons. The extensive use of magnetic resonance imaging has highlighted the white matter alterations in Alzheimer’s dementia (AD) and other neurodegenerative diseases, alterations which are early, extended, and regionally selective. Given that the white matter turnover is considerable in the adulthood, and that myelin repair is currently recognized as being the only true reparative capability of the mature CNS, oligodendrocyte precursor cells (OPCs), the cells that differentiate in oligodendrocyte, responsible for myelin formation and repair, are regarded as a potential target for neuroprotection. In this review, several aspects of the OPC biology are reviewed. The histology and functional role of OPCs in the neurovascular-neuroglial unit as described in preclinical and clinical studies on AD is discussed, such as the OPC vulnerability to hypoxia-ischemia, neuroinflammation, and amyloid deposition. Finally, the position of OPCs in drug discovery strategies for dementia is discussed.
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20
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Abstract
The use of ex vivo compound action potential (CAP) recordings from intact optic nerves is an ideal model to study white matter function without the influence of gray matter. Here, we describe how freshly dissected optic nerves are placed in a humidified recording chamber and how evoked CAPs are recorded and monitored in real time for up to 10 h. Evoked CAP recordings allow for white matter to be studied under acute challenges such as anoxia, hypoxia, aglycemia, and ischemia.
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Affiliation(s)
- Chinthasagar Bastian
- Department of Neurosciences, Lerner Research Institute, Cleveland Clinic Foundation, Cleveland, OH, USA
| | - Sylvain Brunet
- Department of Neurosciences, Lerner Research Institute, Cleveland Clinic Foundation, Cleveland, OH, USA
| | - Selva Baltan
- Department of Neurosciences, Lerner Research Institute, Cleveland Clinic Foundation, Cleveland, OH, USA.
- Anesthesia and Perioperative Medicine (APOM), Oregon Health and Science University, Portland, OR, USA.
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21
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Bastian C, Day J, Politano S, Quinn J, Brunet S, Baltan S. Preserving Mitochondrial Structure and Motility Promotes Recovery of White Matter After Ischemia. Neuromolecular Med 2019; 21:484-492. [PMID: 31152363 PMCID: PMC6884671 DOI: 10.1007/s12017-019-08550-w] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2019] [Accepted: 05/20/2019] [Indexed: 12/23/2022]
Abstract
Stroke significantly affects white matter in the brain by impairing axon function, which results in clinical deficits. Axonal mitochondria are highly dynamic and are transported via microtubules in the anterograde or retrograde direction, depending upon axonal energy demands. Recently, we reported that mitochondrial division inhibitor 1 (Mdivi-1) promotes axon function recovery by preventing mitochondrial fission only when applied during ischemia. Application of Mdivi-1 after injury failed to protect axon function. Interestingly, L-NIO, which is a NOS3 inhibitor, confers post-ischemic protection to axon function by attenuating mitochondrial fission and preserving mitochondrial motility via conserving levels of the microtubular adaptor protein Miro-2. We propose that preventing mitochondrial fission protects axon function during injury, but that restoration of mitochondrial motility is more important to promote axon function recovery after injury. Thus, Miro-2 may be a therapeutic molecular target for recovery following a stroke.
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Affiliation(s)
- Chinthasagar Bastian
- Department of Neurosciences, Lerner Research Institute, Cleveland Clinic Foundation, 9500 Euclid Avenue/NC30, Cleveland, OH, 44195, USA
| | - Jerica Day
- Department of Neurosciences, Lerner Research Institute, Cleveland Clinic Foundation, 9500 Euclid Avenue/NC30, Cleveland, OH, 44195, USA
| | - Stephen Politano
- Department of Neurosciences, Lerner Research Institute, Cleveland Clinic Foundation, 9500 Euclid Avenue/NC30, Cleveland, OH, 44195, USA
| | - John Quinn
- Department of Neurosciences, Lerner Research Institute, Cleveland Clinic Foundation, 9500 Euclid Avenue/NC30, Cleveland, OH, 44195, USA
| | - Sylvain Brunet
- Department of Neurosciences, Lerner Research Institute, Cleveland Clinic Foundation, 9500 Euclid Avenue/NC30, Cleveland, OH, 44195, USA
| | - Selva Baltan
- Department of Neurosciences, Lerner Research Institute, Cleveland Clinic Foundation, 9500 Euclid Avenue/NC30, Cleveland, OH, 44195, USA.
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22
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Baldassarro VA, Marchesini A, Giardino L, Calzà L. Differential effects of glucose deprivation on the survival of fetal versus adult neural stem cells-derived oligodendrocyte precursor cells. Glia 2019; 68:898-917. [PMID: 31755592 DOI: 10.1002/glia.23750] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2019] [Revised: 10/28/2019] [Accepted: 10/29/2019] [Indexed: 12/27/2022]
Abstract
Impaired myelination is a key feature in neonatal hypoxia/ischemia (HI), the most common perinatal/neonatal cause of death and permanent disabilities, which is triggered by the establishment of an inflammatory and hypoxic environment during the most critical period of myelin development. This process is dependent on oligodendrocyte precursor cells (OPCs) and their capability to differentiate into mature oligodendrocytes. In this study, we investigated the vulnerability of fetal and adult OPCs derived from neural stem cells (NSCs) to inflammatory and HI insults. The resulting OPCs/astrocytes cultures were exposed to cytokines to mimic inflammation, or to oxygen-glucose deprivation (OGD) to mimic an HI condition. The differentiation of both fetal and adult OPCs is completely abolished following exposure to inflammatory cytokines, while only fetal-derived OPCs degenerate when exposed to OGD. We then investigated possible mechanisms involved in OGD-mediated toxicity: (a) T3-mediated maturation induction; (b) glutamate excitotoxicity; (c) glucose metabolism. We found that while no substantial differences were observed in T3 intracellular content regulation and glutamate-mediated toxicity, glucose deprivation lead to selective OPC cell death and impaired differentiation in fetal cultures only. These results indicate that the biological response of OPCs to inflammation and demyelination is different in fetal and adult cells, and that the glucose metabolism perturbation in fetal central nervous system (CNS) may significantly contribute to neonatal pathologies. An understanding of the underlying molecular mechanism will contribute greatly to differentiating myelination enhancing and neuroprotective therapies for neonatal and adult CNS white matter lesions.
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Affiliation(s)
- Vito Antonio Baldassarro
- Health Science and Technologies Interdepartmental Center for Industrial Research (HST-ICIR), University of Bologna, Bologna, Italy.,Department of Pharmacy and Biotechnology, University of Bologna, Bologna, Italy.,Institut de Génétique et de Biologie Moléculaire et Cellulaire (IGBMC), Illkirch, France
| | | | - Luciana Giardino
- Health Science and Technologies Interdepartmental Center for Industrial Research (HST-ICIR), University of Bologna, Bologna, Italy.,IRET Foundation, Ozzano Emilia, Italy.,Department of Veterinary Medical Sciences, University of Bologna, Bologna, Italy
| | - Laura Calzà
- Health Science and Technologies Interdepartmental Center for Industrial Research (HST-ICIR), University of Bologna, Bologna, Italy.,Department of Pharmacy and Biotechnology, University of Bologna, Bologna, Italy.,IRET Foundation, Ozzano Emilia, Italy
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23
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The Na +/Ca 2+ exchangers in demyelinating diseases. Cell Calcium 2019; 85:102130. [PMID: 31812115 DOI: 10.1016/j.ceca.2019.102130] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2019] [Accepted: 11/20/2019] [Indexed: 12/15/2022]
Abstract
Intracellular [Na+]i and [Ca2+]i imbalance significantly contribute to neuro-axonal dysfunctions and maladaptive myelin repair or remyelination failure in chronic inflammatory demyelinating diseases such as multiple sclerosis. Progress in recent years has led to significant advances in understanding how [Ca2+]i signaling network drive degeneration or remyelination of demyelinated axons. The Na+/Ca2+ exchangers (NCXs), a transmembrane protein family including three members encoded by ncx1, ncx2, and ncx3 genes, are emerging important regulators of [Na+]i and [Ca2+]i both in neurons and glial cells. Here we review recent advance highlighting the role of NCX exchangers in axons and myelin-forming cells, i.e. oligodendrocytes, which represent the major targets of the aberrant inflammatory attack in multiple sclerosis. The contribution of NCX subtypes to axonal pathology and myelin synthesis will be discussed. Although a definitive understanding of mechanisms regulating axonal pathology and remyelination failure in chronic demyelinating diseases is still lacking and requires further investigation, current knowledge suggest that NCX activity plays a crucial role in these processes. Defining the relative contributions of each NCX transporter in axon pathology and myelinating glia will constitute not only a major advance in understanding in detail the intricate mechanism of neurodegeneration and remyelination failure in demyelinating diseases but also will help to identify neuroprotective or remyelinating strategies targeting selective NCX exchangers as a means of treating MS.
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Axonal degeneration in an in vitro model of ischemic white matter injury. Neurobiol Dis 2019; 134:104672. [PMID: 31707117 DOI: 10.1016/j.nbd.2019.104672] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2019] [Revised: 10/18/2019] [Accepted: 11/06/2019] [Indexed: 01/15/2023] Open
Abstract
Ischemic white matter injuries underlie cognitive decline in the elderly and vascular dementia. Ischemia in the subcortical white matter is caused by chronic reduction of blood flow due to narrowing of small arterioles. However, it remains unclear how chronic ischemia leads to white matter pathology. We aimed to develop an in vitro model of ischemic white matter injury using organotypic slice cultures. Cultured cerebellar slices preserved fully myelinated white matter tracts that were amenable to chronic hypoxic insult. Prolonged hypoxia caused progressive morphological evidence of axonal degeneration with focal constrictions and swellings. In contrast, myelin sheaths and oligodendrocytes exhibited remarkable resilience to hypoxia. The cytoskeletal degradation of axons was accompanied by mitochondrial shortening and lysosomal activation. Multiple pharmacological manipulations revealed that the AMPA glutamate receptor, calpain proteolysis, and lysosomal proteases were independently implicated in hypoxia-induced axonal degeneration in our model. Thus, our in vitro model would be a novel experimental system to explore molecular mechanisms of ischemic white matter injury. Furthermore, we verified that the in vitro assay could be successfully utilized to screen for molecules that can ameliorate hypoxia/ischemia-induced axonal degeneration.
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25
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Volpe JJ. Dysmaturation of Premature Brain: Importance, Cellular Mechanisms, and Potential Interventions. Pediatr Neurol 2019; 95:42-66. [PMID: 30975474 DOI: 10.1016/j.pediatrneurol.2019.02.016] [Citation(s) in RCA: 181] [Impact Index Per Article: 36.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/30/2019] [Revised: 02/12/2019] [Accepted: 02/19/2019] [Indexed: 02/07/2023]
Abstract
Prematurity, especially preterm birth (less than 32 weeks' gestation), is common and associated with high rates of both survival and neurodevelopmental disability, especially apparent in cognitive spheres. The neuropathological substrate of this disability is now recognized to be related to a variety of dysmaturational disturbances of the brain. These disturbances follow initial brain injury, particularly cerebral white matter injury, and involve many of the extraordinary array of developmental events active in cerebral white and gray matter structures during the premature period. This review delineates these developmental events and the dysmaturational disturbances that occur in premature infants. The cellular mechanisms involved in the genesis of the dysmaturation are emphasized, with particular focus on the preoligodendrocyte. A central role for the diffusely distributed activated microglia and reactive astrocytes in the dysmaturation is now apparent. As these dysmaturational cellular mechanisms appear to occur over a relatively long time window, interventions to prevent or ameliorate the dysmaturation, that is, neurorestorative interventions, seem possible. Such interventions include pharmacologic agents, especially erythropoietin, and particular attention has also been paid to such nutritional factors as quality and source of milk, breastfeeding, polyunsaturated fatty acids, iron, and zinc. Recent studies also suggest a potent role for interventions directed at various experiential factors in the neonatal period and infancy, i.e., provision of optimal auditory and visual exposures, minimization of pain and stress, and a variety of other means of environmental behavioral enrichment, in enhancing brain development.
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Affiliation(s)
- Joseph J Volpe
- Department of Neurology, Harvard Medical School, Boston, Massachusetts; Department of Pediatric Newborn Medicine, Harvard Medical School, Boston, Massachusetts.
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26
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T-Regulatory Cells Confer Increased Myelination and Stem Cell Activity after Stroke-Induced White Matter Injury. J Clin Med 2019; 8:jcm8040537. [PMID: 31010132 PMCID: PMC6518209 DOI: 10.3390/jcm8040537] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2019] [Revised: 04/05/2019] [Accepted: 04/17/2019] [Indexed: 12/29/2022] Open
Abstract
Stroke-induced hypoxia causes oligodendrocyte death due to inflammation, lack of oxygen and exacerbation of cell death. Bone marrow-derived stem cells (BMSCs) possess an endogenous population of T-regulatory cells (Tregs) which reduce secretion of pro-inflammatory cytokines that lead to secondary cell death. Here, we hypothesize that oligodendrocyte progenitor cells (OPCs) cultured with BMSCs containing their native Treg population show greater cell viability, less pro-inflammatory cytokine secretion and greater myelin production after exposure to oxygen-glucose deprivation and reoxygenation (OGD/R) than OPCs cultured without Tregs. OPCs were cultured and then exposed to OGD/R. BMSCs with or without Tregs were added to the co-culture immediately after ischemia. The Tregs were depleted by running the BMSCs through a column containing a magnetic substrate. Fibroblast growth factor beta (FGF-β) and interleukin 6 (IL-6) ELISAs determined BMSC activity levels. Immunohistochemistry assessed OPC differentiation. OPCs cultured with BMSCs containing their endogenous Tregs showed increased myelin production compared to the BMSCs with depleted Tregs. IL-6 and FGF-β were increased in the group cultured with Tregs. Collectively, these results suggest that BMSCs containing Tregs are more therapeutically active, and that Tregs have beneficial effects on OPCs subjected to ischemia. Tregs play an important role in stem cell therapy and can potentially treat white matter injury post-stroke.
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Ponnusamy V, Yip PK. The role of microRNAs in newborn brain development and hypoxic ischaemic encephalopathy. Neuropharmacology 2019; 149:55-65. [PMID: 30716413 DOI: 10.1016/j.neuropharm.2018.11.041] [Citation(s) in RCA: 34] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2018] [Revised: 11/28/2018] [Accepted: 11/30/2018] [Indexed: 02/08/2023]
Abstract
Neonates can develop hypoxic-ischaemic encephalopathy (HIE) due to lack of blood supply or oxygen, resulting in a major cause of death and disability among term newborns. However, current definitive treatment of therapeutic hypothermia, will only benefit one out of nine babies. Furthermore, the mechanisms of HIE and therapeutic hypothermia are not fully understood. Recently, microRNAs (miRNAs) have become of interest to many researchers due to their important role in post-transcriptional control and deep evolutionary history. Despite this, role of miRNAs in newborns with HIE remains largely unknown due to limited research in this field. Therefore, this review aims to understand the role of miRNAs in normal brain development and HIE pathophysiology with reliance on extrapolated data from other diseases, ages and species due to current limited data. This will provide us with an overview of how miRNAs in normal brain development changes after HIE. Furthermore, it will indicate how miRNAs are affected specifically or globally by the various pathophysiological events. In addition, we discuss about how drugs and commercially available agents can specifically target certain miRNAs as a mechanism of action and potential safety issue with off-target effects. Improving our understanding of the role of miRNAs on the cellular response after HIE would enhance the success of effective diagnosis, prognosis, and treatment of newborns with HIE.
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Affiliation(s)
- Vennila Ponnusamy
- Centre of Genomics and Child Health, Blizard Institute, Barts and London School of Medicine and Dentistry, Queen Mary University of London, UK; Neonatal Intensive Care Unit, Ashford and St. Peter's Hospitals NHS Trust, Chertsey, UK.
| | - Ping K Yip
- Center of Neuroscience, Surgery and Trauma, Blizard Institute, Barts and London School of Medicine and Dentistry, Queen Mary University of London, UK.
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28
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Fern R, Matute C. Glutamate receptors and white matter stroke. Neurosci Lett 2018; 694:86-92. [PMID: 30476568 DOI: 10.1016/j.neulet.2018.11.031] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2018] [Revised: 11/19/2018] [Accepted: 11/21/2018] [Indexed: 12/23/2022]
Abstract
White matter (WM) damage during ischemia occurs at multiple sites including myelin, oligodendrocytes, astrocytes and axons. A major driver of WM demise is excitoxicity as a consequence of excessive glutamate release by vesicular and non-vesicular mechanisms from axons and glial cells. This results in over-activation of ionotropic glutamate receptors (GluRs) profusely expressed by all cell compartments in WM. Thus, blocking excitotoxicity in WM with selective antagonists of those receptors has a potential therapeutic value. The significance of WM GluR expression for WM stroke injury is the focus of this review, and we will examine the role of GluRs in injury to myelin, oligodendrocytes, astrocytes and the axon cylinder.
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Affiliation(s)
- Robert Fern
- Faculty of Medicine and Dentistry, University of Plymouth, Plymouth, United Kingdom
| | - Carlos Matute
- Achucarro Basque Center for Neuroscience, CIBERNED and Department of Neuroscience, University of the Basque Country, Leioa, Spain.
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29
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Wang F, Cao Y, Ma L, Pei H, Rausch WD, Li H. Dysfunction of Cerebrovascular Endothelial Cells: Prelude to Vascular Dementia. Front Aging Neurosci 2018; 10:376. [PMID: 30505270 PMCID: PMC6250852 DOI: 10.3389/fnagi.2018.00376] [Citation(s) in RCA: 91] [Impact Index Per Article: 15.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2018] [Accepted: 10/29/2018] [Indexed: 12/19/2022] Open
Abstract
Vascular dementia (VaD) is the second most common type of dementia after Alzheimer's disease (AD), characterized by progressive cognitive impairment, memory loss, and thinking or speech problems. VaD is usually caused by cerebrovascular disease, during which, cerebrovascular endothelial cells (CECs) are vulnerable. CEC dysfunction occurs before the onset of VaD and can eventually lead to dysregulation of cerebral blood flow and blood-brain barrier damage, followed by the activation of glia and inflammatory environment in the brain. White matter, neuronal axons, and synapses are compromised in this process, leading to cognitive impairment. The present review summarizes the mechanisms underlying CEC impairment during hypoperfusion and pathological role of CECs in VaD. Through the comprehensive examination and summarization, endothelial nitric oxide synthase (eNOS)/nitric oxide (NO) signaling pathway, Ras homolog gene family member A (RhoA) signaling pathway, and CEC-derived caveolin-1 (CAV-1) are proposed to serve as targets of new drugs for the treatment of VaD.
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Affiliation(s)
- Feixue Wang
- Department of Geriatrics, Xiyuan Hospital of China Academy of Chinese Medical Sciences, Beijing, China
| | - Yu Cao
- Department of Geriatrics, Xiyuan Hospital of China Academy of Chinese Medical Sciences, Beijing, China
| | - Lina Ma
- Department of Geriatrics, Xiyuan Hospital of China Academy of Chinese Medical Sciences, Beijing, China
| | - Hui Pei
- Department of Geriatrics, Xiyuan Hospital of China Academy of Chinese Medical Sciences, Beijing, China
| | - Wolf Dieter Rausch
- Department for Biomedical Sciences, Institute of Medical Biochemistry, University of Veterinary Medicine Vienna, Vienna, Austria
| | - Hao Li
- Department of Geriatrics, Xiyuan Hospital of China Academy of Chinese Medical Sciences, Beijing, China
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30
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CK2 inhibition protects white matter from ischemic injury. Neurosci Lett 2018; 687:37-42. [PMID: 30125643 DOI: 10.1016/j.neulet.2018.08.021] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2018] [Revised: 08/13/2018] [Accepted: 08/14/2018] [Indexed: 11/21/2022]
Abstract
Strokes occur predominantly in the elderly and white matter (WM) is injured in most strokes, contributing to the disability associated with clinical deficits. Casein kinase 2 (CK2) is expressed in neuronal cells and was reported to be neuroprotective during cerebral ischemia. Recently, we reported that CK2 is abundantly expressed by glial cells and myelin. However, in contrast to its role in cerebral (gray matter) ischemia, CK2 activation during ischemia mediated WM injury via the CDK5 and AKT/GSK3β signaling pathways (Bastian et al., 2018). Subsequently, CK2 inhibition using the small molecule inhibitor CX-4945 correlated with preservation of oligodendrocytes as well as conservation of axon structure and axonal mitochondria, leading to improved functional recovery. Notably, CK2 inhibition promoted WM function when applied before or after ischemic injury by differentially regulating the CDK5 and AKT/GSK3β pathways. Specifically, blockade of the active conformation of AKT conferred post-ischemic protection to young, aging, and old WM, suggesting a common therapeutic target across age groups. CK2 inhibitors are currently being used in clinical trials for cancer patients; therefore, it is important to consider the potential benefits of CK2 inhibitors during an ischemic attack.
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31
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Fowler JH, McQueen J, Holland PR, Manso Y, Marangoni M, Scott F, Chisholm E, Scannevin RH, Hardingham GE, Horsburgh K. Dimethyl fumarate improves white matter function following severe hypoperfusion: Involvement of microglia/macrophages and inflammatory mediators. J Cereb Blood Flow Metab 2018; 38:1354-1370. [PMID: 28606007 PMCID: PMC6077928 DOI: 10.1177/0271678x17713105] [Citation(s) in RCA: 42] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
The brain's white matter is highly vulnerable to reductions in cerebral blood flow via mechanisms that may involve elevated microgliosis and pro-inflammatory pathways. In the present study, the effects of severe cerebral hypoperfusion were investigated on white matter function and inflammation. Male C57Bl/6J mice underwent bilateral common carotid artery stenosis and white matter function was assessed at seven days with electrophysiology in response to evoked compound action potentials (CAPs) in the corpus callosum. The peak latency of CAPs and axonal refractoriness was increased following hypoperfusion, indicating a marked functional impairment in white matter, which was paralleled by axonal and myelin pathology and increased density and numbers of microglia/macrophages. The functional impairment in peak latency was significantly correlated with increased microglia/macrophages. Dimethyl fumarate (DMF; 100 mg/kg), a drug with anti-inflammatory properties, was found to reduce peak latency but not axonal refractoriness. DMF had no effect on hypoperfusion-induced axonal and myelin pathology. The density of microglia/macrophages was significantly increased in vehicle-treated hypoperfused mice, whereas DMF-treated hypoperfused mice had similar levels to that of sham-treated mice. The study suggests that increased microglia/macrophages following cerebral hypoperfusion contributes to the functional impairment in white matter that may be amenable to modulation by DMF.
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Affiliation(s)
- Jill H Fowler
- 1 Centre for Neuroregeneration, University of Edinburgh, Edinburgh, UK
| | - Jamie McQueen
- 1 Centre for Neuroregeneration, University of Edinburgh, Edinburgh, UK.,2 Centre for Integrative Physiology, University of Edinburgh, Edinburgh, UK
| | - Philip R Holland
- 1 Centre for Neuroregeneration, University of Edinburgh, Edinburgh, UK.,3 Current Address: Department of Basic and Clinical Neuroscience, Institute of Psychiatry, Psychology and Neuroscience, King's College London, London, UK
| | - Yasmina Manso
- 1 Centre for Neuroregeneration, University of Edinburgh, Edinburgh, UK.,4 Current Address: Developmental Neurobiology and Regeneration Lab, Parc Científic de Barcelona, Spain
| | - Martina Marangoni
- 1 Centre for Neuroregeneration, University of Edinburgh, Edinburgh, UK.,5 Current Address: Department of Health Sciences, University of Florence, Florence, Italy
| | - Fiona Scott
- 1 Centre for Neuroregeneration, University of Edinburgh, Edinburgh, UK
| | - Emma Chisholm
- 1 Centre for Neuroregeneration, University of Edinburgh, Edinburgh, UK
| | | | - Giles E Hardingham
- 2 Centre for Integrative Physiology, University of Edinburgh, Edinburgh, UK.,7 The UK Dementia Research Institute at The University of Edinburgh
| | - Karen Horsburgh
- 1 Centre for Neuroregeneration, University of Edinburgh, Edinburgh, UK.,8 Centre for Cognitive Ageing and Cognitive Epidemiology, University of Edinburgh, Edinburgh, UK
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32
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Bastian C, Quinn J, Tripathi A, Aquila D, McCray A, Dutta R, Baltan S, Brunet S. CK2 inhibition confers functional protection to young and aging axons against ischemia by differentially regulating the CDK5 and AKT signaling pathways. Neurobiol Dis 2018; 126:47-61. [PMID: 29944965 DOI: 10.1016/j.nbd.2018.05.011] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2018] [Revised: 05/08/2018] [Accepted: 05/21/2018] [Indexed: 12/25/2022] Open
Abstract
White matter (WM) is injured in most strokes, which contributes to functional deficits during recovery. Casein kinase 2 (CK2) is a protein kinase that is expressed in brain, including WM. To assess the impact of CK2 inhibition on axon recovery following oxygen glucose deprivation (OGD), mouse optic nerves (MONs), which are pure WM tracts, were subjected to OGD with or without the selective CK2 inhibitor CX-4945. CX-4945 application preserved axon function during OGD and promoted axon function recovery when applied before or after OGD. This protective effect of CK2 inhibition correlated with preservation of oligodendrocytes and conservation of axon structure and axonal mitochondria. To investigate the pertinent downstream signaling pathways, siRNA targeting the CK2α subunit identified CDK5 and AKT as downstream molecules. Consequently, MK-2206 and roscovitine, which are selective AKT and CDK5 inhibitors, respectively, protected young and aging WM function only when applied before OGD. However, a novel pan-AKT allosteric inhibitor, ARQ-092, which targets both the inactive and active conformations of AKT, conferred protection to young and aging axons when applied before or after OGD. These results suggest that AKT and CDK5 signaling contribute to the WM functional protection conferred by CK2 inhibition during ischemia, while inhibition of activated AKT signaling plays the primary role in post-ischemic protection conferred by CK2 inhibition in WM independent of age. CK2 inhibitors are currently being used in clinical trials for cancer patients; therefore, our results will provide rationale for repurposing these drugs as therapeutic options for stroke patients by adding novel targets.
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Affiliation(s)
- Chinthasagar Bastian
- Departments of Neurosciences, Cleveland Clinic, Cleveland, OH 44195, United States of America
| | - John Quinn
- Departments of Neurosciences, Cleveland Clinic, Cleveland, OH 44195, United States of America
| | - Ajai Tripathi
- Departments of Neurosciences, Cleveland Clinic, Cleveland, OH 44195, United States of America
| | - Danielle Aquila
- Departments of Neurosciences, Cleveland Clinic, Cleveland, OH 44195, United States of America
| | - Andrew McCray
- Departments of Neurosciences, Cleveland Clinic, Cleveland, OH 44195, United States of America
| | - Ranjan Dutta
- Departments of Neurosciences, Cleveland Clinic, Cleveland, OH 44195, United States of America
| | - Selva Baltan
- Departments of Neurosciences, Cleveland Clinic, Cleveland, OH 44195, United States of America.
| | - Sylvain Brunet
- Departments of Neurosciences, Cleveland Clinic, Cleveland, OH 44195, United States of America.
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33
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Cai W, Yang T, Liu H, Han L, Zhang K, Hu X, Zhang X, Yin KJ, Gao Y, Bennett MVL, Leak RK, Chen J. Peroxisome proliferator-activated receptor γ (PPARγ): A master gatekeeper in CNS injury and repair. Prog Neurobiol 2017; 163-164:27-58. [PMID: 29032144 DOI: 10.1016/j.pneurobio.2017.10.002] [Citation(s) in RCA: 153] [Impact Index Per Article: 21.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2017] [Revised: 10/06/2017] [Accepted: 10/08/2017] [Indexed: 01/06/2023]
Abstract
Peroxisome proliferator-activated receptor γ (PPARγ) is a widely expressed ligand-modulated transcription factor that governs the expression of genes involved in inflammation, redox equilibrium, trophic factor production, insulin sensitivity, and the metabolism of lipids and glucose. Synthetic PPARγ agonists (e.g. thiazolidinediones) are used to treat Type II diabetes and have the potential to limit the risk of developing brain injuries such as stroke by mitigating the influence of comorbidities. If brain injury develops, PPARγ serves as a master gatekeeper of cytoprotective stress responses, improving the chances of cellular survival and recovery of homeostatic equilibrium. In the acute injury phase, PPARγ directly restricts tissue damage by inhibiting the NFκB pathway to mitigate inflammation and stimulating the Nrf2/ARE axis to neutralize oxidative stress. During the chronic phase of acute brain injuries, PPARγ activation in injured cells culminates in the repair of gray and white matter, preservation of the blood-brain barrier, reconstruction of the neurovascular unit, resolution of inflammation, and long-term functional recovery. Thus, PPARγ lies at the apex of cell fate decisions and exerts profound effects on the chronic progression of acute injury conditions. Here, we review the therapeutic potential of PPARγ in stroke and brain trauma and highlight the novel role of PPARγ in long-term tissue repair. We describe its structure and function and identify the genes that it targets. PPARγ regulation of inflammation, metabolism, cell fate (proliferation/differentiation/maturation/survival), and many other processes also has relevance to other neurological diseases. Therefore, PPARγ is an attractive target for therapies against a number of progressive neurological disorders.
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Affiliation(s)
- Wei Cai
- Pittsburgh Institute of Brain Disorders & Recovery and Department of Neurology, University of Pittsburgh, Pittsburgh, PA 15213, USA
| | - Tuo Yang
- Pittsburgh Institute of Brain Disorders & Recovery and Department of Neurology, University of Pittsburgh, Pittsburgh, PA 15213, USA
| | - Huan Liu
- Pittsburgh Institute of Brain Disorders & Recovery and Department of Neurology, University of Pittsburgh, Pittsburgh, PA 15213, USA
| | - Lijuan Han
- Pittsburgh Institute of Brain Disorders & Recovery and Department of Neurology, University of Pittsburgh, Pittsburgh, PA 15213, USA
| | - Kai Zhang
- Pittsburgh Institute of Brain Disorders & Recovery and Department of Neurology, University of Pittsburgh, Pittsburgh, PA 15213, USA
| | - Xiaoming Hu
- Pittsburgh Institute of Brain Disorders & Recovery and Department of Neurology, University of Pittsburgh, Pittsburgh, PA 15213, USA; State Key Laboratory of Medical Neurobiology and Institutes of Brain Science, Fudan University, Shanghai 200032, China; Geriatric Research, Education and Clinical Center, Veterans Affairs Pittsburgh Health Care System, Pittsburgh PA, USA
| | - Xuejing Zhang
- Pittsburgh Institute of Brain Disorders & Recovery and Department of Neurology, University of Pittsburgh, Pittsburgh, PA 15213, USA
| | - Ke-Jie Yin
- Pittsburgh Institute of Brain Disorders & Recovery and Department of Neurology, University of Pittsburgh, Pittsburgh, PA 15213, USA
| | - Yanqin Gao
- State Key Laboratory of Medical Neurobiology and Institutes of Brain Science, Fudan University, Shanghai 200032, China
| | - Michael V L Bennett
- Dominick P. Purpura Department of Neuroscience, Albert Einstein College of Medicine, Bronx, NY 10461, USA
| | - Rehana K Leak
- Division of Pharmaceutical Sciences, School of Pharmacy, Duquesne University, Pittsburgh, PA 15282, USA.
| | - Jun Chen
- Pittsburgh Institute of Brain Disorders & Recovery and Department of Neurology, University of Pittsburgh, Pittsburgh, PA 15213, USA; State Key Laboratory of Medical Neurobiology and Institutes of Brain Science, Fudan University, Shanghai 200032, China; Geriatric Research, Education and Clinical Center, Veterans Affairs Pittsburgh Health Care System, Pittsburgh PA, USA.
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Schampel A, Volovitch O, Koeniger T, Scholz CJ, Jörg S, Linker RA, Wischmeyer E, Wunsch M, Hell JW, Ergün S, Kuerten S. Nimodipine fosters remyelination in a mouse model of multiple sclerosis and induces microglia-specific apoptosis. Proc Natl Acad Sci U S A 2017; 114:E3295-E3304. [PMID: 28381594 PMCID: PMC5402421 DOI: 10.1073/pnas.1620052114] [Citation(s) in RCA: 46] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
Despite continuous interest in multiple sclerosis (MS) research, there is still a lack of neuroprotective strategies, because the main focus has remained on modulating the immune response. Here we performed in-depth analysis of neurodegeneration in experimental autoimmune encephalomyelitis (EAE) and in in vitro studies regarding the effect of the well-established L-type calcium channel antagonist nimodipine. Nimodipine treatment attenuated clinical EAE and spinal cord degeneration and promoted remyelination. Surprisingly, we observed calcium channel-independent effects on microglia, resulting in apoptosis. These effects were cell-type specific and irrespective of microglia polarization. Apoptosis was accompanied by decreased levels of nitric oxide (NO) and inducible NO synthase (iNOS) in cell culture as well as decreased iNOS and reactive oxygen species levels in EAE. In addition, increased numbers of Olig2+APC+ oligodendrocytes were detected. Overall, nimodipine application seems to generate a favorable environment for regenerative processes and therefore could be a treatment option for MS, because it combines features of immunomodulation with beneficial effects on neuroregeneration.
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Affiliation(s)
- Andrea Schampel
- Department of Anatomy and Cell Biology, University of Würzburg, 97070 Wuerzburg, Germany
| | - Oleg Volovitch
- Department of Anatomy and Cell Biology, University of Cologne, 50931 Cologne, Germany
| | - Tobias Koeniger
- Department of Anatomy and Cell Biology, University of Würzburg, 97070 Wuerzburg, Germany
| | - Claus-Jürgen Scholz
- Core Unit Systems Medicine, University Hospital of Würzburg, 97080 Wuerzburg, Germany
- The Life & Medical Sciences Institute, University of Bonn, 53113 Bonn, Germany
| | - Stefanie Jörg
- Department of Neurology, Friedrich-Alexander University Erlangen-Nuremberg, 91054 Erlangen, Germany
| | - Ralf A Linker
- Department of Neurology, Friedrich-Alexander University Erlangen-Nuremberg, 91054 Erlangen, Germany
| | - Erhard Wischmeyer
- Institute of Physiology, Molecular Electrophysiology, University of Würzburg, 97070 Wuerzburg, Germany
| | - Marie Wunsch
- Department of Anatomy and Cell Biology, University of Würzburg, 97070 Wuerzburg, Germany
| | - Johannes W Hell
- Department of Pharmacology, University of California, Davis, CA 95616
| | - Süleyman Ergün
- Department of Anatomy and Cell Biology, University of Würzburg, 97070 Wuerzburg, Germany
| | - Stefanie Kuerten
- Department of Anatomy and Cell Biology, University of Würzburg, 97070 Wuerzburg, Germany;
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35
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The role of Ca 2+-calmodulin stimulated protein kinase II in ischaemic stroke - A potential target for neuroprotective therapies. Neurochem Int 2017; 107:33-42. [PMID: 28153786 DOI: 10.1016/j.neuint.2017.01.012] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2016] [Revised: 01/17/2017] [Accepted: 01/24/2017] [Indexed: 01/26/2023]
Abstract
Studies in multiple experimental systems show that Ca2+-calmodulin stimulated protein kinase II (CaMKII) is a major mediator of ischaemia-induced cell death and suggest that CaMKII would be a good target for neuroprotective therapies in acute treatment of stroke. However, as CaMKII regulates many cellular processes in many tissues any clinical treatment involving the inhibition of CaMKII would need to be able to specifically target the functions of ischaemia-activated CaMKII. In this review we summarise new developments in our understanding of the molecular mechanisms involved in ischaemia-induced CaMKII-mediated cell death that have identified ways in which such specificity of CaMKII inhibition after stroke could be achieved. We also review the mechanisms and phases of tissue damage in ischaemic stroke to identify where and when CaMKII-mediated mechanisms may be involved.
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36
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Lakhani B, Hayward KS, Boyd LA. Hemispheric asymmetry in myelin after stroke is related to motor impairment and function. NEUROIMAGE-CLINICAL 2017; 14:344-353. [PMID: 28229041 PMCID: PMC5312556 DOI: 10.1016/j.nicl.2017.01.009] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/19/2016] [Revised: 01/03/2017] [Accepted: 01/10/2017] [Indexed: 02/02/2023]
Abstract
The relationships between impairment, function, arm use and underlying brain structure following stroke remain unclear. Although diffusion weighted imaging is useful in broadly assessing white matter structure, it has limited utility in identifying specific underlying neurobiological components, such as myelin. The purpose of the present study was to explore relationships between myelination and impairment, function and activity in individuals with chronic stroke. Assessments of paretic upper-extremity impairment and function were administered, and 72-hour accelerometer based activity monitoring was conducted on 19 individuals with chronic stroke. Participants completed a magnetic resonance imaging protocol that included a high resolution T1 anatomical scan and a multi-component T2 relaxation imaging scan to quantify myelin water fraction (MWF). MWF was automatically parcellated from pre- and post-central subcortical regions of interest and quantified as an asymmetry ratio (contralesional/ipsilesional). Cluster analysis was used to group more and less impaired individuals based on Fugl-Meyer upper extremity scores. A significantly higher precentral MWF asymmetry ratio was found in the more impaired group compared to the less impaired group (p < 0.001). There were no relationships between MWF asymmetry ratio and upper-limb use. Stepwise multiple linear regression identified precentral MWF asymmetry as the only variable to significantly predict impairment and motor function in the upper extremity (UE). These results suggest that asymmetric myelination in a motor specific brain area is a significant predictor of upper-extremity impairment and function in individuals with chronic stroke. As such, myelination may be utilized as a more specific marker of the neurobiological changes that predict long term impairment and recovery from stroke.
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Key Words
- AC, Activity Count
- ANCOVA, Analysis of Covariance
- AR, Asymmetry Ratio
- Accelerometry
- Biomarkers
- CST, Corticospinal Tract
- DTI, Diffusion Tensor Imaging
- FM, Fugl-Meyer
- GRASE, Gradient and Spin Echo
- MANCOVA, Multivariate Analysis of Covariance
- MR, Magnetic Resonance
- MWF, Myelin Water Fraction
- Motor control
- Myelin
- Stroke
- UE, Upper Extremity
- WMFT, Wolf Motor Function Test
- White matter
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Affiliation(s)
- Bimal Lakhani
- Department of Physical Therapy, University of British Columbia, Vancouver, BC V6T 1Z3, Canada
| | - Kathryn S Hayward
- Department of Physical Therapy, University of British Columbia, Vancouver, BC V6T 1Z3, Canada; Stroke Division, Florey Institute of Neuroscience and Mental Health, University of Melbourne, Melbourne, VIC 3084, Australia; NHMRC Centre of Research Excellence in Stroke Rehabilitation and Brain Recovery, Australia
| | - Lara A Boyd
- Department of Physical Therapy, University of British Columbia, Vancouver, BC V6T 1Z3, Canada
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A Novel Approach for Studying the Physiology and Pathophysiology of Myelinated and Non-Myelinated Axons in the CNS White Matter. PLoS One 2016; 11:e0165637. [PMID: 27829055 PMCID: PMC5102346 DOI: 10.1371/journal.pone.0165637] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2016] [Accepted: 10/14/2016] [Indexed: 11/19/2022] Open
Abstract
Advances in brain connectomics set the need for detailed knowledge of functional properties of myelinated and non-myelinated (if present) axons in specific white matter pathways. The corpus callosum (CC), a major white matter structure interconnecting brain hemispheres, is extensively used for studying CNS axonal function. Unlike another widely used CNS white matter preparation, the optic nerve where all axons are myelinated, the CC contains also a large population of non-myelinated axons, making it particularly useful for studying both types of axons. Electrophysiological studies of optic nerve use suction electrodes on nerve ends to stimulate and record compound action potentials (CAPs) that adequately represent its axonal population, whereas CC studies use microelectrodes (MEs), recording from a limited area within the CC. Here we introduce a novel robust isolated "whole" CC preparation comparable to optic nerve. Unlike ME recordings where the CC CAP peaks representing myelinated and non-myelinated axons vary broadly in size, "whole" CC CAPs show stable reproducible ratios of these two main peaks, and also reveal a third peak, suggesting a distinct group of smaller caliber non-myelinated axons. We provide detailed characterization of "whole" CC CAPs and conduction velocities of myelinated and non-myelinated axons along the rostro-caudal axis of CC body and show advantages of this preparation for comparing axonal function in wild type and dysmyelinated shiverer mice, studying the effects of temperature dependence, bath-applied drugs and ischemia modeled by oxygen-glucose deprivation. Due to the isolation from gray matter, our approach allows for studying CC axonal function without possible "contamination" by reverberating signals from gray matter. Our analysis of "whole" CC CAPs revealed higher complexity of myelinated and non-myelinated axonal populations, not noticed earlier. This preparation may have a broad range of applications as a robust model for studying myelinated and non-myelinated axons of the CNS in various experimental models.
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O'Hare Doig RL, Bartlett CA, Smith NM, Hodgetts SI, Dunlop SA, Hool L, Fitzgerald M. Specific combinations of ion channel inhibitors reduce excessive Ca 2+ influx as a consequence of oxidative stress and increase neuronal and glial cell viability in vitro. Neuroscience 2016; 339:450-462. [PMID: 27725216 DOI: 10.1016/j.neuroscience.2016.10.005] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2016] [Revised: 09/15/2016] [Accepted: 10/02/2016] [Indexed: 01/02/2023]
Abstract
Combinations of Ca2+ channel inhibitors have been proposed as an effective means to prevent excess Ca2+ flux and death of neurons and glia following neurotrauma in vivo. However, it is not yet known if beneficial outcomes such as improved viability have been due to direct effects on intracellular Ca2+ concentrations. Here, the effects of combinations of Lomerizine (Lom), 2,3-dioxo-7-(1H-imidazol-1-yl)6-nitro-1,2,3,4-tetrahydro-1-quinoxalinyl]acetic acid monohydrate (YM872), 3,5-dimethyl-1-adamantanamine (memantine (Mem)) and/or adenosine 5'-triphosphate periodate oxidized sodium salt (oxATP) to block voltage-gated Ca2+ channels, Ca2+ permeable α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA) receptors, NMDA receptors and purinergic P2X7 receptors (P2X7R) respectively, on Ca2+ concentration and viability of rat primary mixed cortical (MC) cultures exposed to hydrogen peroxide (H2O2) insult, were assessed. The contribution of ryanodine-sensitive intracellular stores to intracellular Ca2+ concentration was also assessed. Live cell calcium imaging revealed that a 30min H2O2 insult induced a slow increase in intracellular Ca2+, in part from intracellular sources, associated with loss of cell viability by 6h. Most combinations of inhibitors that included oxATP significantly decreased Ca2+ influx and increased cell viability when administered simultaneously with H2O2. However, reductions in intracellular Ca2+ concentration were not always linked to improved cell viability. Examination of the density of specific cell subpopulations demonstrated that most combinations of inhibitors that included oxATP preserved NG2+ non-oligodendroglial cells, but preservation of astrocytes and neurons required additional inhibitors. Olig2+ oligodendroglia and ED-1+ activated microglia/macrophages were not preserved by any of the inhibitor combinations. These data indicate that following H2O2 insult, limiting intracellular Ca2+ entry via P2X7R is generally associated with increased cell viability. Protection of NG2+ non-oligodendroglial cells by Ca2+ channel inhibitor combinations may contribute to observed beneficial outcomes in vivo.
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Affiliation(s)
- Ryan L O'Hare Doig
- Experimental and Regenerative Neurosciences, The University of Western Australia, Crawley, Western Australia, Australia; School of Animal Biology, The University of Western Australia, Crawley, Western Australia, Australia; School of Anatomy, Physiology and Human Biology, The University of Western Australia, Crawley, Western Australia, Australia
| | - Carole A Bartlett
- Experimental and Regenerative Neurosciences, The University of Western Australia, Crawley, Western Australia, Australia; School of Animal Biology, The University of Western Australia, Crawley, Western Australia, Australia
| | - Nicole M Smith
- Experimental and Regenerative Neurosciences, The University of Western Australia, Crawley, Western Australia, Australia; School of Animal Biology, The University of Western Australia, Crawley, Western Australia, Australia; School of Chemistry and Biochemistry, The University of Western Australia, Crawley, Western Australia, Australia
| | - Stuart I Hodgetts
- Experimental and Regenerative Neurosciences, The University of Western Australia, Crawley, Western Australia, Australia; School of Anatomy, Physiology and Human Biology, The University of Western Australia, Crawley, Western Australia, Australia
| | - Sarah A Dunlop
- Experimental and Regenerative Neurosciences, The University of Western Australia, Crawley, Western Australia, Australia; School of Animal Biology, The University of Western Australia, Crawley, Western Australia, Australia
| | - Livia Hool
- School of Anatomy, Physiology and Human Biology, The University of Western Australia, Crawley, Western Australia, Australia; Victor Chang Cardiac Research Institute, Sydney, New South Wales, Australia
| | - Melinda Fitzgerald
- Experimental and Regenerative Neurosciences, The University of Western Australia, Crawley, Western Australia, Australia; School of Animal Biology, The University of Western Australia, Crawley, Western Australia, Australia.
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Boscia F, Begum G, Pignataro G, Sirabella R, Cuomo O, Casamassa A, Sun D, Annunziato L. Glial Na(+) -dependent ion transporters in pathophysiological conditions. Glia 2016; 64:1677-97. [PMID: 27458821 DOI: 10.1002/glia.23030] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2016] [Revised: 06/22/2016] [Accepted: 06/29/2016] [Indexed: 12/12/2022]
Abstract
Sodium dynamics are essential for regulating functional processes in glial cells. Indeed, glial Na(+) signaling influences and regulates important glial activities, and plays a role in neuron-glia interaction under physiological conditions or in response to injury of the central nervous system (CNS). Emerging studies indicate that Na(+) pumps and Na(+) -dependent ion transporters in astrocytes, microglia, and oligodendrocytes regulate Na(+) homeostasis and play a fundamental role in modulating glial activities in neurological diseases. In this review, we first briefly introduced the emerging roles of each glial cell type in the pathophysiology of cerebral ischemia, Alzheimer's disease, epilepsy, Parkinson's disease, Amyotrophic Lateral Sclerosis, and myelin diseases. Then, we discussed the current knowledge on the main roles played by the different glial Na(+) -dependent ion transporters, including Na(+) /K(+) ATPase, Na(+) /Ca(2+) exchangers, Na(+) /H(+) exchangers, Na(+) -K(+) -Cl(-) cotransporters, and Na(+) - HCO3- cotransporter in the pathophysiology of the diverse CNS diseases. We highlighted their contributions in cell survival, synaptic pathology, gliotransmission, pH homeostasis, and their role in glial activation, migration, gliosis, inflammation, and tissue repair processes. Therefore, this review summarizes the foundation work for targeting Na(+) -dependent ion transporters in glia as a novel strategy to control important glial activities associated with Na(+) dynamics in different neurological disorders. GLIA 2016;64:1677-1697.
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Affiliation(s)
- Francesca Boscia
- Division of Pharmacology, Department of Neuroscience, Reproductive, and Odontostomatological Sciences, School of Medicine, Federico II University of Naples, Naples, Italy
| | - Gulnaz Begum
- Department of Neurology, University of Pittsburgh Medical School
| | - Giuseppe Pignataro
- Division of Pharmacology, Department of Neuroscience, Reproductive, and Odontostomatological Sciences, School of Medicine, Federico II University of Naples, Naples, Italy
| | - Rossana Sirabella
- Division of Pharmacology, Department of Neuroscience, Reproductive, and Odontostomatological Sciences, School of Medicine, Federico II University of Naples, Naples, Italy
| | - Ornella Cuomo
- Division of Pharmacology, Department of Neuroscience, Reproductive, and Odontostomatological Sciences, School of Medicine, Federico II University of Naples, Naples, Italy
| | - Antonella Casamassa
- Division of Pharmacology, Department of Neuroscience, Reproductive, and Odontostomatological Sciences, School of Medicine, Federico II University of Naples, Naples, Italy
| | - Dandan Sun
- Department of Neurology, University of Pittsburgh Medical School.,Veterans Affairs Pittsburgh Health Care System, Geriatric Research, Educational and Clinical Center, Pittsburgh, Pennsylvania, 15213
| | - Lucio Annunziato
- Division of Pharmacology, Department of Neuroscience, Reproductive, and Odontostomatological Sciences, School of Medicine, Federico II University of Naples, Naples, Italy
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40
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Christensen PC, Samadi-Bahrami Z, Pavlov V, Stys PK, Moore GRW. Ionotropic glutamate receptor expression in human white matter. Neurosci Lett 2016; 630:1-8. [PMID: 27443784 DOI: 10.1016/j.neulet.2016.07.030] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2016] [Revised: 07/14/2016] [Accepted: 07/17/2016] [Indexed: 01/01/2023]
Abstract
Glutamate is the key excitatory neurotransmitter of the central nervous system (CNS). Its role in human grey matter transmission is well understood, but this is less clear in white matter (WM). Ionotropic glutamate receptors (iGluR) are found on both neuronal cell bodies and glia as well as on myelinated axons in rodents, and rodent WM tissue is capable of glutamate release. Thus, rodent WM expresses many of the components of the traditional grey matter neuron-to-neuron synapse, but to date this has not been shown for human WM. We demonstrate the presence of iGluRs in human WM by immunofluorescence employing high-resolution spectral confocal imaging. We found that the obligatory N-methyl-d-aspartic acid (NMDA) receptor subunit GluN1 and the α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA) receptor subunit GluA4 co-localized with myelin, oligodendroglial cell bodies and processes. Additionally, GluA4 colocalized with axons, often in distinct clusters. These findings may explain why human WM is vulnerable to excitotoxic events following acute insults such as stroke and traumatic brain injury and in more chronic inflammatory conditions such as multiple sclerosis (MS). Further exploration of human WM glutamate signalling could pave the way for developing future therapies modulating the glutamate-mediated damage in these and other CNS disorders.
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Affiliation(s)
- Pia Crone Christensen
- Hotchkiss Brain Institute, Department of Clinical Neuroscience, University of Calgary, Calgary, Alberta, T2 N 4N1, Canada
| | - Zahra Samadi-Bahrami
- ICORD, (International Collaboration on Repair Discoveries), Department of Pathology and Laboratory Medicine, University of British Columbia, Canada
| | - Vlady Pavlov
- ICORD, (International Collaboration on Repair Discoveries), Department of Pathology and Laboratory Medicine, University of British Columbia, Canada
| | - Peter K Stys
- Hotchkiss Brain Institute, Department of Clinical Neuroscience, University of Calgary, Calgary, Alberta, T2 N 4N1, Canada.
| | - G R Wayne Moore
- ICORD, (International Collaboration on Repair Discoveries), Department of Pathology and Laboratory Medicine, University of British Columbia, Canada
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Glutamate and ATP at the Interface Between Signaling and Metabolism in Astroglia: Examples from Pathology. Neurochem Res 2016; 42:19-34. [PMID: 26915104 DOI: 10.1007/s11064-016-1848-6] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/01/2016] [Revised: 01/21/2016] [Accepted: 01/22/2016] [Indexed: 12/17/2022]
Abstract
Glutamate is the main excitatory transmitter in the brain, while ATP represents the most important energy currency in any living cell. Yet, these chemicals play an important role in both processes, enabling them with dual-acting functions in metabolic and intercellular signaling pathways. Glutamate can fuel ATP production, while ATP can act as a transmitter in intercellular signaling. We discuss the interface between glutamate and ATP in signaling and metabolism of astrocytes. Not only do glutamate and ATP cross each other's paths in physiology of the brain, but they also do so in its pathology. We present the fabric of this process in (patho)physiology through the discussion of synthesis and metabolism of ATP and glutamate in astrocytes as well as by providing a general description of astroglial receptors for these molecules along with the downstream signaling pathways that may be activated. It is astroglial receptors for these dual-acting molecules that could hold a key for medical intervention in pathological conditions. We focus on two examples disclosing the role of activation of astroglial ATP and glutamate receptors in pathology of two kinds of brain tissue, gray matter and white matter, respectively. Interventions at the interface of metabolism and signaling show promise for translational medicine.
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42
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Ransom BR, Goldberg MP, Arai K, Baltan S. White Matter Pathophysiology. Stroke 2016. [DOI: 10.1016/b978-0-323-29544-4.00009-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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43
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Ferraz MM, Sab IM, Silva MA, Santos DA, Ferraz MR. Prenatal Hypoxia Ischemia Increases Male Rat Sexual Behavior. J Sex Med 2015; 12:2013-21. [DOI: 10.1111/jsm.13006] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
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Baltan S. Age-specific localization of NMDA receptors on oligodendrocytes dictates axon function recovery after ischemia. Neuropharmacology 2015; 110:626-632. [PMID: 26407763 DOI: 10.1016/j.neuropharm.2015.09.015] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2015] [Revised: 08/18/2015] [Accepted: 09/12/2015] [Indexed: 11/26/2022]
Abstract
Oligodendrocytes and axons are the main targets of an ischemic white matter injury and the resultant loss of axon function underlies the clinical disability in patients who survive a stroke. The cellular mechanisms of ischemic injury change as a function of age in concordance with age-mediated structural changes in white matter. Shorter periods of injury cause rapid and robust loss of axon function together with widespread oligodendrocyte death. While blockade of NMDA receptors fails to benefit axon function, removal of extracellular Ca2+ during ischemia remarkably promotes axon function recovery in young white matter. However, these same approaches hinder axon function recovery and fail to protect oligodendrocytes in aging white matter. The obligatory GluN1 subunit of the NMDA receptor exhibits an age-specific expression pattern such that in young adult white matter, it is mostly localized on oligodendrocyte cell bodies, while in aging white matter, it is also observed on myelin processes. This age-dependent re-localization and redistribution pattern mimics GluN1 expression observed during development, but in reverse order. During development, GluN1 immunoreactivity traffics from astrocytes at postnatal day 4-11 (P4-11) to myelin processes at P12-18 and to oligodendrocytes cell bodies at P19-21. Although immature axons are more resistant to ischemia, blockade of NMDA receptors during ischemia at P4-11 and P12-18 worsens axon function recovery and fails to benefit axons at P19-21. Thus, age-specific expression patterns of NMDA receptor localization may seem to modulate the plasticity of oligodendrocytes and myelin in response to ischemia as a function of age in white matter. This article is part of the Special Issue entitled 'Oligodendrocytes in Health and Disease'.
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Affiliation(s)
- Selva Baltan
- Department of Neurosciences, Lerner Research Institute, Cleveland Clinic Foundation, Cleveland, OH, USA.
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45
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Back SA. Brain Injury in the Preterm Infant: New Horizons for Pathogenesis and Prevention. Pediatr Neurol 2015; 53:185-92. [PMID: 26302698 PMCID: PMC4550810 DOI: 10.1016/j.pediatrneurol.2015.04.006] [Citation(s) in RCA: 74] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/26/2015] [Revised: 03/24/2015] [Accepted: 04/12/2015] [Indexed: 10/23/2022]
Abstract
Preterm neonates are surviving with a milder spectrum of motor and cognitive disabilities that appear to be related to widespread disturbances in cell maturation that target cerebral gray and white matter. Whereas the preterm brain was previously at high risk for destructive lesions, preterm survivors now commonly display less severe injury that is associated with aberrant regeneration and repair responses that result in reduced cerebral growth. Impaired cerebral white matter growth is related to myelination disturbances that are initiated by acute death of premyelinating oligodendrocytes, but are followed by rapid regeneration of premyelinating oligodendrocytes that fail to normally mature to myelinating cells. Although immature neurons are more resistant to cell death than mature neurons, they display widespread disturbances in maturation of their dendritic arbors and synapses, which further contributes to impaired cerebral growth. Thus, even more mild cerebral injury involves disrupted repair mechanisms in which neurons and premyelinating oligodendrocytes fail to fully mature during a critical window in development of neural circuitry. These recently recognized distinct forms of cerebral gray and white matter dysmaturation raise new diagnostic challenges and suggest new therapeutic strategies to promote brain growth and repair.
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Affiliation(s)
- Stephen A. Back
- Departments of Pediatrics and Neurology, Oregon Health & Science University, Portland, Oregon, U.S.A
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46
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Abstract
Neuroglia, the "glue" that fills the space between neurons in the central nervous system, takes active part in nerve cell signaling. Neuroglial cells, astroglia, oligodendroglia, and microglia, are together about as numerous as neurons in the brain as a whole, and in the cerebral cortex grey matter, but the proportion varies widely among brain regions. Glial volume, however, is less than one-fifth of the tissue volume in grey matter. When stimulated by neurons or other cells, neuroglial cells release gliotransmitters by exocytosis, similar to neurotransmitter release from nerve endings, or by carrier-mediated transport or channel flux through the plasma membrane. Gliotransmitters include the common neurotransmitters glutamate and GABA, the nonstandard amino acid d-serine, the high-energy phosphate ATP, and l-lactate. The latter molecule is a "buffer" between glycolytic and oxidative metabolism as well as a signaling substance recently shown to act on specific lactate receptors in the brain. Complementing neurotransmission at a synapse, neuroglial transmission often implies diffusion of the transmitter over a longer distance and concurs with the concept of volume transmission. Transmission from glia modulates synaptic neurotransmission based on energetic and other local conditions in a volume of tissue surrounding the individual synapse. Neuroglial transmission appears to contribute significantly to brain functions such as memory, as well as to prevalent neuropathologies.
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Affiliation(s)
- Vidar Gundersen
- SN-Lab, Division of Anatomy, Department of Molecular Medicine, Institute of Basic Medical Sciences, and CMBN/SERTA/Healthy Brain Ageing Centre, University of Oslo, Oslo, Norway; Department of Neurology, Oslo University Hospital-Rikshospitalet, Oslo, Norway; Center for Healthy Aging, Department of Neuroscience and Pharmacology, Faculty of Health Sciences, University of Copenhagen, Copenhagen, Denmark; and Brain and Muscle Energy Group, Department of Oral Biology and Division of Anatomy, Department of Molecular Medicine, University of Oslo, Oslo, Norway
| | - Jon Storm-Mathisen
- SN-Lab, Division of Anatomy, Department of Molecular Medicine, Institute of Basic Medical Sciences, and CMBN/SERTA/Healthy Brain Ageing Centre, University of Oslo, Oslo, Norway; Department of Neurology, Oslo University Hospital-Rikshospitalet, Oslo, Norway; Center for Healthy Aging, Department of Neuroscience and Pharmacology, Faculty of Health Sciences, University of Copenhagen, Copenhagen, Denmark; and Brain and Muscle Energy Group, Department of Oral Biology and Division of Anatomy, Department of Molecular Medicine, University of Oslo, Oslo, Norway
| | - Linda Hildegard Bergersen
- SN-Lab, Division of Anatomy, Department of Molecular Medicine, Institute of Basic Medical Sciences, and CMBN/SERTA/Healthy Brain Ageing Centre, University of Oslo, Oslo, Norway; Department of Neurology, Oslo University Hospital-Rikshospitalet, Oslo, Norway; Center for Healthy Aging, Department of Neuroscience and Pharmacology, Faculty of Health Sciences, University of Copenhagen, Copenhagen, Denmark; and Brain and Muscle Energy Group, Department of Oral Biology and Division of Anatomy, Department of Molecular Medicine, University of Oslo, Oslo, Norway
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47
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Rottlaender A, Kuerten S. Stepchild or Prodigy? Neuroprotection in Multiple Sclerosis (MS) Research. Int J Mol Sci 2015; 16:14850-65. [PMID: 26140377 PMCID: PMC4519875 DOI: 10.3390/ijms160714850] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2015] [Revised: 06/23/2015] [Accepted: 06/26/2015] [Indexed: 11/20/2022] Open
Abstract
Multiple sclerosis (MS) is an autoimmune disorder of the central nervous system (CNS) and characterized by the infiltration of immune cells, demyelination and axonal loss. Loss of axons and nerve fiber pathology are widely accepted as correlates of neurological disability. Hence, it is surprising that the development of neuroprotective therapies has been neglected for a long time. A reason for this could be the diversity of the underlying mechanisms, complex changes in nerve fiber pathology and the absence of biomarkers and tools to quantify neuroregenerative processes. Present therapeutic strategies are aimed at modulating or suppressing the immune response, but do not primarily attenuate axonal pathology. Yet, target-oriented neuroprotective strategies are essential for the treatment of MS, especially as severe damage of nerve fibers mostly occurs in the course of disease progression and cannot be impeded by immune modulatory drugs. This review shall depict the need for neuroprotective strategies and elucidate difficulties and opportunities.
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Affiliation(s)
- Andrea Rottlaender
- Department of Anatomy and Cell Biology, University of Wuerzburg, Wuerzburg 97070, Germany.
| | - Stefanie Kuerten
- Department of Anatomy and Cell Biology, University of Wuerzburg, Wuerzburg 97070, Germany.
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Evonuk KS, Baker BJ, Doyle RE, Moseley CE, Sestero CM, Johnston BP, De Sarno P, Tang A, Gembitsky I, Hewett SJ, Weaver CT, Raman C, DeSilva TM. Inhibition of System Xc(-) Transporter Attenuates Autoimmune Inflammatory Demyelination. THE JOURNAL OF IMMUNOLOGY 2015; 195:450-463. [PMID: 26071560 DOI: 10.4049/jimmunol.1401108] [Citation(s) in RCA: 63] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/01/2014] [Accepted: 05/11/2015] [Indexed: 01/15/2023]
Abstract
T cell infiltration into the CNS is a significant underlying pathogenesis in autoimmune inflammatory demyelinating diseases. Several lines of evidence suggest that glutamate dysregulation in the CNS is an important consequence of immune cell infiltration in neuroinflammatory demyelinating diseases; yet, the causal link between inflammation and glutamate dysregulation is not well understood. A major source of glutamate release during oxidative stress is the system Xc(-) transporter; however, this mechanism has not been tested in animal models of autoimmune inflammatory demyelination. We find that pharmacological and genetic inhibition of system Xc(-) attenuates chronic and relapsing-remitting experimental autoimmune encephalomyelitis (EAE). Remarkably, pharmacological blockade of system Xc(-) 7 d after induction of EAE attenuated T cell infiltration into the CNS, but not T cell activation in the periphery. Mice harboring a Slc7a11 (xCT) mutation that inactivated system Xc(-) were resistant to EAE, corroborating a central role for system Xc(-) in mediating immune cell infiltration. We next examined the role of the system Xc(-) transporter in the CNS after immune cell infiltration. Pharmacological inhibitors of the system Xc(-) transporter administered during the first relapse in a SJL animal model of relapsing-remitting EAE abrogated clinical disease, inflammation, and myelin loss. Primary coculture studies demonstrate that myelin-specific CD4(+) Th1 cells provoke microglia to release glutamate via the system Xc(-) transporter, causing excitotoxic death to mature myelin-producing oligodendrocytes. Taken together, these studies support a novel role for the system Xc(-) transporter in mediating T cell infiltration into the CNS as well as promoting myelin destruction after immune cell infiltration in EAE.
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Affiliation(s)
- Kirsten S Evonuk
- Center for Glial Biology in Medicine, University of Alabama at Birmingham, Birmingham, AL, 35294.,Department of Physical Medicine Rehabilitation, University of Alabama at Birmingham, Birmingham, AL, 35294
| | - Brandi J Baker
- Center for Glial Biology in Medicine, University of Alabama at Birmingham, Birmingham, AL, 35294.,Department of Physical Medicine Rehabilitation, University of Alabama at Birmingham, Birmingham, AL, 35294
| | - Ryan E Doyle
- Center for Glial Biology in Medicine, University of Alabama at Birmingham, Birmingham, AL, 35294.,Department of Physical Medicine Rehabilitation, University of Alabama at Birmingham, Birmingham, AL, 35294
| | - Carson E Moseley
- Department of Pathology, University of Alabama at Birmingham, AL, 35294
| | - Christine M Sestero
- Department of Medicine, University of Alabama at Birmingham, Birmingham, AL, 35294.,Department of Biology, Chemistry, and Mathematics, University of Montevallo, Montevallo, AL 35115
| | - Bryce P Johnston
- Center for Glial Biology in Medicine, University of Alabama at Birmingham, Birmingham, AL, 35294.,Department of Physical Medicine Rehabilitation, University of Alabama at Birmingham, Birmingham, AL, 35294
| | - Patrizia De Sarno
- Department of Cell, Developmental and Integrative Biology, University of Alabama at Birmingham, Birmingham, AL 35294
| | - Andrew Tang
- Department of Physical Medicine Rehabilitation, University of Alabama at Birmingham, Birmingham, AL, 35294
| | - Igor Gembitsky
- Department of Physical Medicine Rehabilitation, University of Alabama at Birmingham, Birmingham, AL, 35294
| | - Sandra J Hewett
- Department of Biology, Program in Neuroscience, Syracuse University, Syracuse, NY, 13244
| | - Casey T Weaver
- Department of Pathology, University of Alabama at Birmingham, AL, 35294
| | - Chander Raman
- Department of Medicine, University of Alabama at Birmingham, Birmingham, AL, 35294
| | - Tara M DeSilva
- Center for Glial Biology in Medicine, University of Alabama at Birmingham, Birmingham, AL, 35294.,Department of Physical Medicine Rehabilitation, University of Alabama at Birmingham, Birmingham, AL, 35294.,Department of Neurobiology, University of Alabama at Birmingham, Birmingham, AL, 35294
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49
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Titomanlio L, Fernández-López D, Manganozzi L, Moretti R, Vexler ZS, Gressens P. Pathophysiology and neuroprotection of global and focal perinatal brain injury: lessons from animal models. Pediatr Neurol 2015; 52:566-584. [PMID: 26002050 PMCID: PMC4720385 DOI: 10.1016/j.pediatrneurol.2015.01.016] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/12/2014] [Revised: 01/16/2015] [Accepted: 01/24/2015] [Indexed: 12/14/2022]
Abstract
BACKGROUND Arterial ischemic stroke occurs more frequently in term newborns than in the elderly, and brain immaturity affects mechanisms of ischemic injury and recovery. The susceptibility to injury of the brain was assumed to be lower in the perinatal period as compared with childhood. This concept was recently challenged by clinical studies showing marked motor disabilities after stroke in neonates, with the severity of motor and cortical sensory deficits similar in both perinatal and childhood ischemic stroke. Our understanding of the triggers and the pathophysiological mechanisms of perinatal stroke has greatly improved in recent years, but many factors remain incompletely understood. METHODS In this review, we focus on the pathophysiology of perinatal stroke and on therapeutic strategies that can protect the immature brain from the consequences of stroke by targeting inflammation and brain microenvironment. RESULTS Studies in neonatal rodent models of cerebral ischemia have suggested a potential role for soluble inflammatory molecules as important modulators of injury and recovery. A great effort is underway to investigate neuroprotective molecules based on our increasing understanding of the pathophysiology. CONCLUSION In this review, we provide a comprehensive summary of new insights concerning pathophysiology of focal and global perinatal brain injury and their implications for new therapeutic approaches.
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Affiliation(s)
- Luigi Titomanlio
- Pediatric Emergency Department, APHP, Robert Debré Hospital, Paris, France
- Inserm, U1141, F-75019 Paris, France
| | - David Fernández-López
- Department of Neurology, University of California San Francisco, San Francisco, CA, 94158-0663, USA
| | - Lucilla Manganozzi
- Pediatric Emergency Department, APHP, Robert Debré Hospital, Paris, France
- Inserm, U1141, F-75019 Paris, France
| | | | - Zinaida S. Vexler
- Department of Neurology, University of California San Francisco, San Francisco, CA, 94158-0663, USA
| | - Pierre Gressens
- Inserm, U1141, F-75019 Paris, France
- Univ Paris Diderot, Sorbonne Paris Cité, UMRS 676, F-75019 Paris, France
- PremUP, Paris, France
- Centre for the Developing Brain, King’s College, St Thomas’ Campus, London SE1 7EH, UK
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Shi H, Hu X, Leak RK, Shi Y, An C, Suenaga J, Chen J, Gao Y. Demyelination as a rational therapeutic target for ischemic or traumatic brain injury. Exp Neurol 2015; 272:17-25. [PMID: 25819104 DOI: 10.1016/j.expneurol.2015.03.017] [Citation(s) in RCA: 106] [Impact Index Per Article: 11.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2015] [Revised: 03/15/2015] [Accepted: 03/18/2015] [Indexed: 12/11/2022]
Abstract
Previous research on stroke and traumatic brain injury (TBI) heavily emphasized pathological alterations in neuronal cells within gray matter. However, recent studies have highlighted the equal importance of white matter integrity in long-term recovery from these conditions. Demyelination is a major component of white matter injury and is characterized by loss of the myelin sheath and oligodendrocyte cell death. Demyelination contributes significantly to long-term sensorimotor and cognitive deficits because the adult brain only has limited capacity for oligodendrocyte regeneration and axonal remyelination. In the current review, we will provide an overview of the major causes of demyelination and oligodendrocyte cell death following acute brain injuries, and discuss the crosstalk between myelin, axons, microglia, and astrocytes during the process of demyelination. Recent discoveries of molecules that regulate the processes of remyelination may provide novel therapeutic targets to restore white matter integrity and improve long-term neurological recovery in stroke or TBI patients.
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Affiliation(s)
- Hong Shi
- The State Key Laboratory of Medical Neurobiology, The Institutes of Brain Science and the Collaborative Innovation Center for Brain Science, Fudan University, Shanghai 200032, China; Department of Anesthesiology of Shanghai Pulmonary Hospital, Tongji University, Shanghai 200433, China
| | - Xiaoming Hu
- The State Key Laboratory of Medical Neurobiology, The Institutes of Brain Science and the Collaborative Innovation Center for Brain Science, Fudan University, Shanghai 200032, China; Center of Cerebrovascular Disease Research, University of Pittsburgh School of Medicine, Pittsburgh, PA 15213, USA; Geriatric Research, Education and Clinical Center, Veterans Affairs Pittsburgh Health Care System, Pittsburgh, PA 15261, USA
| | - Rehana K Leak
- Division of Pharmaceutical Sciences, Duquesne University, Pittsburgh, PA 15282, USA
| | - Yejie Shi
- The State Key Laboratory of Medical Neurobiology, The Institutes of Brain Science and the Collaborative Innovation Center for Brain Science, Fudan University, Shanghai 200032, China; Center of Cerebrovascular Disease Research, University of Pittsburgh School of Medicine, Pittsburgh, PA 15213, USA; Geriatric Research, Education and Clinical Center, Veterans Affairs Pittsburgh Health Care System, Pittsburgh, PA 15261, USA
| | - Chengrui An
- The State Key Laboratory of Medical Neurobiology, The Institutes of Brain Science and the Collaborative Innovation Center for Brain Science, Fudan University, Shanghai 200032, China
| | - Jun Suenaga
- Center of Cerebrovascular Disease Research, University of Pittsburgh School of Medicine, Pittsburgh, PA 15213, USA
| | - Jun Chen
- The State Key Laboratory of Medical Neurobiology, The Institutes of Brain Science and the Collaborative Innovation Center for Brain Science, Fudan University, Shanghai 200032, China; Center of Cerebrovascular Disease Research, University of Pittsburgh School of Medicine, Pittsburgh, PA 15213, USA; Geriatric Research, Education and Clinical Center, Veterans Affairs Pittsburgh Health Care System, Pittsburgh, PA 15261, USA.
| | - Yanqin Gao
- The State Key Laboratory of Medical Neurobiology, The Institutes of Brain Science and the Collaborative Innovation Center for Brain Science, Fudan University, Shanghai 200032, China; Center of Cerebrovascular Disease Research, University of Pittsburgh School of Medicine, Pittsburgh, PA 15213, USA.
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