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Haupt M, Gerner ST, Bähr M, Doeppner TR. Quest for Quality in Translational Stroke Research-A New Dawn for Neuroprotection? Int J Mol Sci 2022; 23:5381. [PMID: 35628192 PMCID: PMC9140731 DOI: 10.3390/ijms23105381] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2022] [Revised: 05/10/2022] [Accepted: 05/10/2022] [Indexed: 12/13/2022] Open
Abstract
Despite tremendous progress in modern-day stroke therapy, ischemic stroke remains a disease associated with a high socioeconomic burden in industrialized countries. In light of demographic change, these health care costs are expected to increase even further. The current causal therapeutic treatment paradigms focus on successful thrombolysis or thrombectomy, but only a fraction of patients qualify for these recanalization therapies because of therapeutic time window restrictions or contraindications. Hence, adjuvant therapeutic concepts such as neuroprotection are urgently needed. A bench-to-bedside transfer of neuroprotective approaches under stroke conditions, however, has not been established after more than twenty years of research, albeit a great many data have demonstrated several neuroprotective drugs to be effective in preclinical stroke settings. Prominent examples of substances supported by extensive preclinical evidence but which failed clinical trials are tirilazad and disodium 2,4-sulphophenyl-N-tert-butylnitrone (NXY-059). The NXY-059 trial, for instance, was retrospectively shown to have a seriously weak study design, a trial of insufficient quality and a poor statistical analysis, although it initially met the recommendations of the STAIR committee. In light of currently ongoing novel neuroprotective stroke trials, such as ESCAPE-NA, and to avoid the mistakes made in the past, an improvement in study quality in the field of stroke neuroprotection is urgently needed. In the present review, animal models closely reflecting the "typical" stroke patient, occlusion techniques and the appropriate choice of time windows are discussed. In this context, the STAIR recommendations could provide a useful orientation. Taking all of this into account, a new dawn for neuroprotection might be possible.
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Affiliation(s)
- Matteo Haupt
- Department of Neurology, University of Goettingen Medical School, 37075 Goettingen, Germany;
| | - Stefan T. Gerner
- Department of Neurology, University Hospital Giessen, 35394 Giessen, Germany;
| | - Mathias Bähr
- Department of Neurology, University of Goettingen Medical School, 37075 Goettingen, Germany;
| | - Thorsten R. Doeppner
- Department of Neurology, University of Goettingen Medical School, 37075 Goettingen, Germany;
- Department of Neurology, University Hospital Giessen, 35394 Giessen, Germany;
- Department of Anatomy and Cell Biology, Medical University of Varna, 9002 Varna, Bulgaria
- Research Institute for Health Sciences and Technologies (SABITA), Medipol University Istanbul, Istanbul 34810, Turkey
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2
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Blood-Brain Barrier Transporters: Opportunities for Therapeutic Development in Ischemic Stroke. Int J Mol Sci 2022; 23:ijms23031898. [PMID: 35163820 PMCID: PMC8836701 DOI: 10.3390/ijms23031898] [Citation(s) in RCA: 20] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2021] [Revised: 02/02/2022] [Accepted: 02/04/2022] [Indexed: 12/20/2022] Open
Abstract
Globally, stroke is a leading cause of death and long-term disability. Over the past decades, several efforts have attempted to discover new drugs or repurpose existing therapeutics to promote post-stroke neurological recovery. Preclinical stroke studies have reported successes in identifying novel neuroprotective agents; however, none of these compounds have advanced beyond a phase III clinical trial. One reason for these failures is the lack of consideration of blood-brain barrier (BBB) transport mechanisms that can enable these drugs to achieve efficacious concentrations in ischemic brain tissue. Despite the knowledge that drugs with neuroprotective properties (i.e., statins, memantine, metformin) are substrates for endogenous BBB transporters, preclinical stroke research has not extensively studied the role of transporters in central nervous system (CNS) drug delivery. Here, we review current knowledge on specific BBB uptake transporters (i.e., organic anion transporting polypeptides (OATPs in humans; Oatps in rodents); organic cation transporters (OCTs in humans; Octs in rodents) that can be targeted for improved neuroprotective drug delivery. Additionally, we provide state-of-the-art perspectives on how transporter pharmacology can be integrated into preclinical stroke research. Specifically, we discuss the utility of in vivo stroke models to transporter studies and considerations (i.e., species selection, co-morbid conditions) that will optimize the translational success of stroke pharmacotherapeutic experiments.
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3
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Classification and Characteristics of Mesenchymal Stem Cells and Its Potential Therapeutic Mechanisms and Applications against Ischemic Stroke. Stem Cells Int 2021; 2021:2602871. [PMID: 34795764 PMCID: PMC8595011 DOI: 10.1155/2021/2602871] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2021] [Accepted: 10/11/2021] [Indexed: 12/13/2022] Open
Abstract
Ischemic stroke is a serious cerebral disease that often induces death and long-term disability. As a currently available therapy for recanalization after ischemic stroke, thrombolysis, including intravenous thrombolysis and endovascular therapy, still cannot be applicable to all patients due to the narrow time window. Mesenchymal stem cell (MSC) transplantation therapy, which can trigger neuronal regeneration and repair, has been considered as a significant advance in treatment of ischemic stroke. MSC transplantation therapy has exhibited its potential to improve the neurological function in ischemic stroke. Our review describes the current progress and future perspective of MSC transplantation therapy in ischemic stroke treatment, including cell types, transplantation approaches, therapeutic mechanisms, and preliminary clinical trials of MSC transplantation, for providing us an update role of MSC transplantation in ischemic stroke treatment.
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4
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Lemon N, Canepa E, Ilies MA, Fossati S. Carbonic Anhydrases as Potential Targets Against Neurovascular Unit Dysfunction in Alzheimer’s Disease and Stroke. Front Aging Neurosci 2021; 13:772278. [PMID: 34867298 PMCID: PMC8635164 DOI: 10.3389/fnagi.2021.772278] [Citation(s) in RCA: 23] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2021] [Accepted: 10/20/2021] [Indexed: 12/23/2022] Open
Abstract
The Neurovascular Unit (NVU) is an important multicellular structure of the central nervous system (CNS), which participates in the regulation of cerebral blood flow (CBF), delivery of oxygen and nutrients, immunological surveillance, clearance, barrier functions, and CNS homeostasis. Stroke and Alzheimer Disease (AD) are two pathologies with extensive NVU dysfunction. The cell types of the NVU change in both structure and function following an ischemic insult and during the development of AD pathology. Stroke and AD share common risk factors such as cardiovascular disease, and also share similarities at a molecular level. In both diseases, disruption of metabolic support, mitochondrial dysfunction, increase in oxidative stress, release of inflammatory signaling molecules, and blood brain barrier disruption result in NVU dysfunction, leading to cell death and neurodegeneration. Improved therapeutic strategies for both AD and stroke are needed. Carbonic anhydrases (CAs) are well-known targets for other diseases and are being recently investigated for their function in the development of cerebrovascular pathology. CAs catalyze the hydration of CO2 to produce bicarbonate and a proton. This reaction is important for pH homeostasis, overturn of cerebrospinal fluid, regulation of CBF, and other physiological functions. Humans express 15 CA isoforms with different distribution patterns. Recent studies provide evidence that CA inhibition is protective to NVU cells in vitro and in vivo, in models of stroke and AD pathology. CA inhibitors are FDA-approved for treatment of glaucoma, high-altitude sickness, and other indications. Most FDA-approved CA inhibitors are pan-CA inhibitors; however, specific CA isoforms are likely to modulate the NVU function. This review will summarize the literature regarding the use of pan-CA and specific CA inhibitors along with genetic manipulation of specific CA isoforms in stroke and AD models, to bring light into the functions of CAs in the NVU. Although pan-CA inhibitors are protective and safe, we hypothesize that targeting specific CA isoforms will increase the efficacy of CA inhibition and reduce side effects. More studies to further determine specific CA isoforms functions and changes in disease states are essential to the development of novel therapies for cerebrovascular pathology, occurring in both stroke and AD.
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Affiliation(s)
- Nicole Lemon
- Alzheimer’s Center at Temple (ACT), Lewis Katz School of Medicine, Temple University, Philadelphia, PA, United States
| | - Elisa Canepa
- Alzheimer’s Center at Temple (ACT), Lewis Katz School of Medicine, Temple University, Philadelphia, PA, United States
| | - Marc A. Ilies
- Alzheimer’s Center at Temple (ACT), Lewis Katz School of Medicine, Temple University, Philadelphia, PA, United States
- Department of Pharmaceutical Sciences and Moulder Center for Drug Discovery Research, Temple University School of Pharmacy, Temple University, Philadelphia, PA, United States
| | - Silvia Fossati
- Alzheimer’s Center at Temple (ACT), Lewis Katz School of Medicine, Temple University, Philadelphia, PA, United States
- *Correspondence: Silvia Fossati,
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5
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Bazzigaluppi P, Mester J, Joo IL, Weisspapir I, Dorr A, Koletar MM, Beckett TL, Khosravani H, Carlen P, Stefanovic B. Frequency selective neuronal modulation triggers spreading depolarizations in the rat endothelin-1 model of stroke. J Cereb Blood Flow Metab 2021; 41:2756-2768. [PMID: 33969731 PMCID: PMC8504421 DOI: 10.1177/0271678x211013656] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Ischemia is one of the most common causes of acquired brain injury. Central to its noxious sequelae are spreading depolarizations (SDs), waves of persistent depolarizations which start at the location of the flow obstruction and expand outwards leading to excitotoxic damage. The majority of acute stage of stroke studies to date have focused on the phenomenology of SDs and their association with brain damage. In the current work, we investigated the role of peri-injection zone pyramidal neurons in triggering SDs by optogenetic stimulation in an endothelin-1 rat model of focal ischemia. Our concurrent two photon fluorescence microscopy data and local field potential recordings indicated that a ≥ 60% drop in cortical arteriolar red blood cell velocity was associated with SDs at the ET-1 injection site. SDs were also observed in the peri-injection zone, which subsequently exhibited elevated neuronal activity in the low-frequency bands. Critically, SDs were triggered by low- but not high-frequency optogenetic stimulation of peri-injection zone pyramidal neurons. Our findings depict a complex etiology of SDs post focal ischemia and reveal that effects of neuronal modulation exhibit spectral and spatial selectivity.
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Affiliation(s)
- Paolo Bazzigaluppi
- Sunnybrook Research Institute, Physical Sciences, Toronto, ON, Canada
- Paolo Bazzigaluppi, Sunnybrook Research Institute, 2075 Bayview Ave., S646, Toronto, ON M4N 3M5, Canada.
| | - James Mester
- Sunnybrook Research Institute, Physical Sciences, Toronto, ON, Canada
- Department of Medical Biophysics, Faculty of Medicine, University of Toronto, Toronto, ON, Canada
| | - Illsung L Joo
- Sunnybrook Research Institute, Physical Sciences, Toronto, ON, Canada
| | - Iliya Weisspapir
- Sunnybrook Research Institute, Physical Sciences, Toronto, ON, Canada
| | - Adrienne Dorr
- Sunnybrook Research Institute, Physical Sciences, Toronto, ON, Canada
| | | | - Tina L Beckett
- Sunnybrook Research Institute, Physical Sciences, Toronto, ON, Canada
| | - Houman Khosravani
- Division of Neurology and Interdepartmental Division of Critical Care, Department of Medicine, Sunnybrook Health Sciences Centre, University of Toronto, Toronto, ON, Canada
- Interdepartmental Division of Critical Care, Department of Medicine, University of Toronto, Toronto, ON, Canada
| | - Peter Carlen
- Krembil Research Institute, University of Toronto, Toronto, ON, Canada
| | - Bojana Stefanovic
- Sunnybrook Research Institute, Physical Sciences, Toronto, ON, Canada
- Department of Medical Biophysics, Faculty of Medicine, University of Toronto, Toronto, ON, Canada
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Trotman-Lucas M, Gibson CL. A review of experimental models of focal cerebral ischemia focusing on the middle cerebral artery occlusion model. F1000Res 2021; 10:242. [PMID: 34046164 PMCID: PMC8127011 DOI: 10.12688/f1000research.51752.2] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 05/21/2021] [Indexed: 12/14/2022] Open
Abstract
Cerebral ischemic stroke is a leading cause of death and disability, but current pharmacological therapies are limited in their utility and effectiveness.
In vitro and
in vivo models of ischemic stroke have been developed which allow us to further elucidate the pathophysiological mechanisms of injury and investigate potential drug targets.
In vitro models permit mechanistic investigation of the biochemical and molecular mechanisms of injury but are reductionist and do not mimic the complexity of clinical stroke.
In vivo models of ischemic stroke directly replicate the reduction in blood flow and the resulting impact on nervous tissue. The most frequently used
in vivo model of ischemic stroke is the intraluminal suture middle cerebral artery occlusion (iMCAO) model, which has been fundamental in revealing various aspects of stroke pathology. However, the iMCAO model produces lesion volumes with large standard deviations even though rigid surgical and data collection protocols are followed. There is a need to refine the MCAO model to reduce variability in the standard outcome measure of lesion volume. The typical approach to produce vessel occlusion is to induce an obstruction at the origin of the middle cerebral artery and reperfusion is reliant on the Circle of Willis (CoW). However, in rodents the CoW is anatomically highly variable which could account for variations in lesion volume. Thus, we developed a refined approach whereby reliance on the CoW for reperfusion was removed. This approach improved reperfusion to the ischemic hemisphere, reduced variability in lesion volume by 30%, and reduced group sizes required to determine an effective treatment response by almost 40%. This refinement involves a methodological adaptation of the original surgical approach which we have shared with the scientific community via publication of a visualised methods article and providing hands-on training to other experimental stroke researchers.
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Affiliation(s)
| | - Claire L Gibson
- School of Psychology, University of Nottingham, Nottingham, NG7 2UH, UK
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7
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Sultana S, Burkovskiy I, Zhou J, Kelly MM, Lehmann C. Effect of Cannabinoid 2 Receptor Modulation on the Peripheral Immune Response in Central Nervous System Injury-Induced Immunodeficiency Syndrome. Cannabis Cannabinoid Res 2021; 6:327-339. [PMID: 33998888 DOI: 10.1089/can.2020.0130] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Introduction: Acute central nervous system (CNS) injury, such as stroke, spinal cord injury, or traumatic brain injury can result in dysregulated immune response, and the condition is known as CNS injury-induced immunodeficiency syndrome (CIDS). The endocannabinoid system is an important homeostatic regulator in the CNS and immune system. Activation of cannabinoid 2 receptors (CB2R) on immune cells has been reported to dampen inflammation, suggesting a potential role of CB2R in the peripheral immune response following CNS injury. In this study, we have investigated the effect of CB2R modulation on the peripheral immune response during CIDS. Materials and Methods: Experimental CNS injury was induced in C57BL/6 mice through intracerebral injection of the vasopressor peptide, endothelin-1. A selective CB2R agonist (HU308) was used as an early treatment before the onset of CIDS and AM630, a selective CB2R antagonist, was administered as a later-phase therapy to combat the systemic immunodeficiency following the CNS injury. The peripheral immune response to endotoxin was studied 24 h after the CNS injury using intravital microscopy to examine leukocyte activation within the intestinal microcirculation in mice. Brain infarct size, and plasma levels of cytokines and soluble adhesion molecules were measured as additional parameters for the assessment of treatment outcomes. Results: Our results showed that early CB2R activation with HU308 reduced brain injury size and restored leukocyte response to endotoxin in the peripheral microcirculation. Late CB2R inhibition with AM630 also improved the peripheral leukocyte response to endotoxin and did not exacerbate the extent of brain injury. Discussion: CB2R activation has the potential to mitigate CNS injury as an early treatment by limiting neuroinflammation and preventing the development of CIDS. At the later stage with already-established CIDS, treatment may require dampening CB2R activation to improve the patient's outcome.
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Affiliation(s)
- Saki Sultana
- Department of Anesthesia, Pain Management and Perioperative Medicine, Dalhousie University, Halifax, Canada
| | - Ian Burkovskiy
- Department of Anesthesia, Pain Management and Perioperative Medicine, Dalhousie University, Halifax, Canada
| | - Juan Zhou
- Department of Anesthesia, Pain Management and Perioperative Medicine, Dalhousie University, Halifax, Canada
| | - Melanie M Kelly
- Department of Pharmacology, and Dalhousie University, Halifax, Canada
| | - Christian Lehmann
- Department of Anesthesia, Pain Management and Perioperative Medicine, Dalhousie University, Halifax, Canada.,Department of Pharmacology, and Dalhousie University, Halifax, Canada.,Department of Microbiology and Immunology, Dalhousie University, Halifax, Canada
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8
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Codd LN, Blackmore DG, Vukovic J, Bartlett PF. Exercise reverses learning deficits induced by hippocampal injury by promoting neurogenesis. Sci Rep 2020; 10:19269. [PMID: 33159114 PMCID: PMC7648755 DOI: 10.1038/s41598-020-76176-1] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2020] [Accepted: 10/05/2020] [Indexed: 12/18/2022] Open
Abstract
Hippocampal atrophy and cognitive decline are common sequelae of many neurodegenerative disorders, including stroke. To determine whether cognitive decline can be ameliorated by exercise-induced neurogenesis, C57BL/6 mice in which a unilateral hippocampal injury had been induced by injecting the vasoconstrictor endothelin-1 into their right hippocampus, were run voluntarily for 21 days on a running-wheel. We found the severe deficits in spatial learning, as detected by active place-avoidance task, following injury were almost completely restored in animals that ran whereas those that did not run showed no improvement. We show the increase in neurogenesis found in both the injured and contralateral hippocampi following running was responsible for the restoration of learning since bilateral ablation of newborn doublecortin (DCX)-positive neurons abrogated the cognitive improvement, whereas unilateral ablations of DCX-positive neurons did not prevent recovery, demonstrating that elevated neurogenesis in either the damaged or intact hippocampus is sufficient to reverse hippocampal injury-induced deficits.
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Affiliation(s)
- Lavinia N Codd
- Queensland Brain Institute, The University of Queensland, Brisbane, QLD, 4072, Australia
| | - Daniel G Blackmore
- Queensland Brain Institute, The University of Queensland, Brisbane, QLD, 4072, Australia
| | - Jana Vukovic
- Queensland Brain Institute, The University of Queensland, Brisbane, QLD, 4072, Australia.,School of Biomedical Sciences, The University of Queensland, Brisbane, QLD, 4072, Australia
| | - Perry F Bartlett
- Queensland Brain Institute, The University of Queensland, Brisbane, QLD, 4072, Australia.
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9
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Kuriakose D, Xiao Z. Pathophysiology and Treatment of Stroke: Present Status and Future Perspectives. Int J Mol Sci 2020; 21:E7609. [PMID: 33076218 PMCID: PMC7589849 DOI: 10.3390/ijms21207609] [Citation(s) in RCA: 361] [Impact Index Per Article: 90.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2020] [Revised: 10/08/2020] [Accepted: 10/13/2020] [Indexed: 12/14/2022] Open
Abstract
Stroke is the second leading cause of death and a major contributor to disability worldwide. The prevalence of stroke is highest in developing countries, with ischemic stroke being the most common type. Considerable progress has been made in our understanding of the pathophysiology of stroke and the underlying mechanisms leading to ischemic insult. Stroke therapy primarily focuses on restoring blood flow to the brain and treating stroke-induced neurological damage. Lack of success in recent clinical trials has led to significant refinement of animal models, focus-driven study design and use of new technologies in stroke research. Simultaneously, despite progress in stroke management, post-stroke care exerts a substantial impact on families, the healthcare system and the economy. Improvements in pre-clinical and clinical care are likely to underpin successful stroke treatment, recovery, rehabilitation and prevention. In this review, we focus on the pathophysiology of stroke, major advances in the identification of therapeutic targets and recent trends in stroke research.
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Affiliation(s)
| | - Zhicheng Xiao
- Development and Stem Cells Program, Monash Biomedicine Discovery Institute and Department of Anatomy and Developmental Biology, Monash University, Melbourne, VIC 3800, Australia;
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Engler-Chiurazzi EB, Monaghan KL, Wan ECK, Ren X. Role of B cells and the aging brain in stroke recovery and treatment. GeroScience 2020; 42:1199-1216. [PMID: 32767220 PMCID: PMC7525651 DOI: 10.1007/s11357-020-00242-9] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2020] [Accepted: 07/23/2020] [Indexed: 02/07/2023] Open
Abstract
As mitigation of brain aging continues to be a key public health priority, a wholistic and comprehensive consideration of the aging body has identified immunosenescence as a potential contributor to age-related brain injury and disease. Importantly, the nervous and immune systems engage in bidirectional communication and can exert profound influence on each other. Emerging evidence supports numerous impacts of innate, inflammatory immune responses and adaptive T cell-mediated immunity in neurological function and diseased or injured brain states, such as stroke. Indeed, a growing body of evidence supports key impacts of brain-resident immune cell activation and peripheral immune infiltration in both the post-stroke acute injury phase and the long-term recovery period. As such, modulation of the immune system is an attractive strategy for novel therapeutic interventions for a devastating age-related brain injury for which there are few readily available neuroprotective treatments or neurorestorative approaches. However, the role of B cells in the context of brain function, and specifically in response to stroke, has not been thoroughly elucidated and remains controversial, leaving our understanding of neuroimmune interactions incomplete. Importantly, emerging evidence suggests that B cells are not pathogenic contributors to stroke injury, and in fact may facilitate functional recovery, supporting their potential value as novel therapeutic targets. By summarizing the current knowledge of the role of B cells in stroke pathology and recovery and interpreting their role in the context of their interactions with other immune cells as well as the immunosenescence cascades that alter their function in aged populations, this review supports an increased understanding of the complex interplay between the nervous and immune systems in the context of brain aging, injury, and disease.
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Affiliation(s)
- E. B. Engler-Chiurazzi
- Department of Neuroscience, Rockefeller Neuroscience Institute, West Virginia University, Morgantown, WV 26506 USA
- Center for Basic & Translational Stroke Research, Rockefeller Neuroscience Institute, West Virginia University, Morgantown, WV 26506 USA
| | - K. L. Monaghan
- Center for Basic & Translational Stroke Research, Rockefeller Neuroscience Institute, West Virginia University, Morgantown, WV 26506 USA
- Department of Microbiology, Immunology & Cell Biology, West Virginia University, Morgantown, WV 26506 USA
| | - E. C. K. Wan
- Department of Neuroscience, Rockefeller Neuroscience Institute, West Virginia University, Morgantown, WV 26506 USA
- Center for Basic & Translational Stroke Research, Rockefeller Neuroscience Institute, West Virginia University, Morgantown, WV 26506 USA
- Department of Microbiology, Immunology & Cell Biology, West Virginia University, Morgantown, WV 26506 USA
| | - X. Ren
- Department of Neuroscience, Rockefeller Neuroscience Institute, West Virginia University, Morgantown, WV 26506 USA
- Center for Basic & Translational Stroke Research, Rockefeller Neuroscience Institute, West Virginia University, Morgantown, WV 26506 USA
- Department of Microbiology, Immunology & Cell Biology, West Virginia University, Morgantown, WV 26506 USA
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11
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Panta A, Montgomery K, Nicolas M, Mani KK, Sampath D, Sohrabji F. Mir363-3p Treatment Attenuates Long-Term Cognitive Deficits Precipitated by an Ischemic Stroke in Middle-Aged Female Rats. Front Aging Neurosci 2020; 12:586362. [PMID: 33132904 PMCID: PMC7550720 DOI: 10.3389/fnagi.2020.586362] [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: 07/23/2020] [Accepted: 09/02/2020] [Indexed: 01/29/2023] Open
Abstract
Cognitive impairment and memory loss are commonly seen after stroke and a third of patients will develop signs of dementia a year after stroke. Despite a large number of studies on the beneficial effects of neuroprotectants, few studies have examined the effects of these compounds/interventions on long-term cognitive impairment. Our previous work showed that the microRNA mir363-3p reduced infarct volume and sensory-motor impairment in the acute stage of stroke in middle-aged females but not males. Thus, the present study determined the impact of mir363-3p treatment on stroke-induced cognitive impairment in middle-aged females. Sprague–Dawley female rats (12 months of age) were subjected to middle cerebral artery occlusion (MCAo; or sham surgery) and injected (iv) with mir363-3p mimic (MCAo + mir363-3p) or scrambled oligos (MCAo + scrambled) 4 h later. Sensory-motor performance was assessed in the acute phase (2–5 days after stroke), while all other behaviors were tested 6 months after MCAo (18 months of age). Cognitive function was assessed by the novel object recognition test (declarative memory) and the Barnes maze (spatial memory). The MCAo + scrambled group showed reduced preference for a novel object after the stroke and poor learning in the spatial memory task. In contrast, mir363-3p treated animals were similar to either their baseline performance or to the sham group. Histological analysis showed significant deterioration of specific white matter tracts due to stroke, which was attenuated in mir363-3p treated animals. The present data builds on our previous finding to show that a neuroprotectant can abrogate the long-term effects of stroke.
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Affiliation(s)
- Aditya Panta
- Women's Health in Neuroscience Program, Department of Neuroscience and Experimental Therapeutics, Texas A&M Health Science Center College of Medicine, Texas A&M University, Bryan, TX, United States
| | - Karienn Montgomery
- Women's Health in Neuroscience Program, Department of Neuroscience and Experimental Therapeutics, Texas A&M Health Science Center College of Medicine, Texas A&M University, Bryan, TX, United States
| | - Marissa Nicolas
- Women's Health in Neuroscience Program, Department of Neuroscience and Experimental Therapeutics, Texas A&M Health Science Center College of Medicine, Texas A&M University, Bryan, TX, United States
| | - Kathiresh K Mani
- Women's Health in Neuroscience Program, Department of Neuroscience and Experimental Therapeutics, Texas A&M Health Science Center College of Medicine, Texas A&M University, Bryan, TX, United States
| | - Dayalan Sampath
- Women's Health in Neuroscience Program, Department of Neuroscience and Experimental Therapeutics, Texas A&M Health Science Center College of Medicine, Texas A&M University, Bryan, TX, United States
| | - Farida Sohrabji
- Women's Health in Neuroscience Program, Department of Neuroscience and Experimental Therapeutics, Texas A&M Health Science Center College of Medicine, Texas A&M University, Bryan, TX, United States
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12
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Freitas-Andrade M, Raman-Nair J, Lacoste B. Structural and Functional Remodeling of the Brain Vasculature Following Stroke. Front Physiol 2020; 11:948. [PMID: 32848875 PMCID: PMC7433746 DOI: 10.3389/fphys.2020.00948] [Citation(s) in RCA: 24] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2020] [Accepted: 07/14/2020] [Indexed: 12/12/2022] Open
Abstract
Maintenance of cerebral blood vessel integrity and regulation of cerebral blood flow ensure proper brain function. The adult human brain represents only a small portion of the body mass, yet about a quarter of the cardiac output is dedicated to energy consumption by brain cells at rest. Due to a low capacity to store energy, brain health is heavily reliant on a steady supply of oxygen and nutrients from the bloodstream, and is thus particularly vulnerable to stroke. Stroke is a leading cause of disability and mortality worldwide. By transiently or permanently limiting tissue perfusion, stroke alters vascular integrity and function, compromising brain homeostasis and leading to widespread consequences from early-onset motor deficits to long-term cognitive decline. While numerous lines of investigation have been undertaken to develop new pharmacological therapies for stroke, only few advances have been made and most clinical trials have failed. Overall, our understanding of the acute and chronic vascular responses to stroke is insufficient, yet a better comprehension of cerebrovascular remodeling following stroke is an essential prerequisite for developing novel therapeutic options. In this review, we present a comprehensive update on post-stroke cerebrovascular remodeling, an important and growing field in neuroscience, by discussing cellular and molecular mechanisms involved, sex differences, limitations of preclinical research design and future directions.
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Affiliation(s)
| | - Joanna Raman-Nair
- Neuroscience Program, Ottawa Hospital Research Institute, Ottawa, ON, Canada
| | - Baptiste Lacoste
- Neuroscience Program, Ottawa Hospital Research Institute, Ottawa, ON, Canada
- Department of Cellular and Molecular Medicine, Faculty of Medicine, University of Ottawa, Ottawa, ON, Canada
- Brain and Mind Research Institute, University of Ottawa, Ottawa, ON, Canada
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13
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Poststroke Impairment and Recovery Are Predicted by Task-Specific Regionalization of Injury. J Neurosci 2020; 40:6082-6097. [PMID: 32605940 DOI: 10.1523/jneurosci.0057-20.2020] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2020] [Revised: 06/18/2020] [Accepted: 06/24/2020] [Indexed: 01/01/2023] Open
Abstract
Lesion size and location affect the magnitude of impairment and recovery following stroke, but the precise relationship between these variables and functional outcome is unknown. Herein, we systematically varied the size of strokes in motor cortex and surrounding regions to assess effects on impairment and recovery of function. Female Sprague Dawley rats (N = 64) were evaluated for skilled reaching, spontaneous limb use, and limb placement over a 7 week period after stroke. Exploration and reaching were also tested in a free ranging, more naturalistic, environment. MRI voxel-based analysis of injury volume and its likelihood of including the caudal forelimb area (CFA), rostral forelimb area (RFA), hindlimb (HL) cortex (based on intracranial microstimulation), or their bordering regions were related to both impairment and recovery. Severity of impairment on each task was best predicted by injury in unique regions: impaired reaching, by damage in voxels encompassing CFA/RFA; hindlimb placement, by damage in HL; and spontaneous forelimb use, by damage in CFA. An entirely different set of voxels predicted recovery of function: damage lateral to RFA reduced recovery of reaching, damage medial to HL reduced recovery of hindlimb placing, and damage lateral to CFA reduced recovery of spontaneous limb use. Precise lesion location is an important, but heretofore relatively neglected, prognostic factor in both preclinical and clinical stroke studies, especially those using region-specific therapies, such as transcranial magnetic stimulation.SIGNIFICANCE STATEMENT By estimating lesion location relative to cortical motor representations, we established the relationship between individualized lesion location, and functional impairment and recovery in reaching/grasping, spontaneous limb use, and hindlimb placement during walking. We confirmed that stroke results in impairments to specific motor domains linked to the damaged cortical subregion and that damage encroaching on adjacent regions reduces the ability to recover from initial lesion-induced impairments. Each motor domain encompasses unique brain regions that are most associated with recovery and likely represent targets where beneficial reorganization is taking place. Future clinical trials should use individualized therapies (e.g., transcranial magnetic stimulation, intracerebral stem/progenitor cells) that consider precise lesion location and the specific functional impairments of each subject since these variables can markedly affect therapeutic efficacy.
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14
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Fifield KE, Vanderluit JL. Rapid degeneration of neurons in the penumbra region following a small, focal ischemic stroke. Eur J Neurosci 2020; 52:3196-3214. [DOI: 10.1111/ejn.14678] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2019] [Revised: 12/19/2019] [Accepted: 01/08/2020] [Indexed: 01/04/2023]
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15
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Happ DF, Wegener G, Tasker RA. Effect of ischemic lesions in medial prefrontal cortex and nucleus accumbens on affective behavior in rats. Behav Brain Res 2020; 378:112234. [PMID: 31521735 DOI: 10.1016/j.bbr.2019.112234] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2019] [Revised: 08/13/2019] [Accepted: 09/11/2019] [Indexed: 02/05/2023]
Abstract
Post-stroke depression (PSD) and post-stroke anxiety (PSA) are usually undertreated and many cases may remain undiagnosed, indicating a need for a better understanding of the underlying mechanisms. Current animal models of PSD and PSA using the middle cerebral artery occlusion model may be associated with motor deficits that can interfere with behavioral tests of depression- and anxiety-like behavior. Unilateral lesions of the medial prefrontal cortex (mPFC) have been reported to induce a depression- and anxiety-like phenotype in mice. The aim of this study was to examine the effects of unilateral microinjections of the vasoconstrictor endothelin-1 (ET-1) in the mPFC alone or in combination with the nucleus accumbens (NAc) on the behavior of rats after 2 and 6 weeks. Specifically, we measured anxiety- and depressive-like behavior, locomotion, and cognition. ET-1 injections in the mPFC and NAc resulted in replicable and localized lesions. Lesions to the mPFC and NAc resulted in more time spent in the open arms of the Elevated Plus Maze compared to sham-operated animals at 2 weeks post stroke, indicating decreased anxiety. This effect did not persist until 6 weeks post injection. No differences in locomotion, cognition and depressive-like behavior were found at either time point. In summary, unilateral lesions of mPFC and NAc did not produce a reliable and persistent anxiety and depression phenotype in rats.
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Affiliation(s)
- Denise F Happ
- Translational Neuropsychiatry Unit, Department of Clinical Medicine, Aarhus University, Denmark.
| | - Gregers Wegener
- Translational Neuropsychiatry Unit, Department of Clinical Medicine, Aarhus University, Denmark
| | - R Andrew Tasker
- Translational Neuropsychiatry Unit, Department of Clinical Medicine, Aarhus University, Denmark; Department of Biomedical Sciences, University of Prince Edward Island, Canada
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16
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Reproductive Senescence and Ischemic Stroke Remodel the Gut Microbiome and Modulate the Effects of Estrogen Treatment in Female Rats. Transl Stroke Res 2019; 11:812-830. [PMID: 31845185 DOI: 10.1007/s12975-019-00760-5] [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: 04/10/2019] [Revised: 10/29/2019] [Accepted: 11/19/2019] [Indexed: 12/17/2022]
Abstract
Our previous work has shown that reproductively senescent (or middle-aged; 10-12-month-old) Sprague-Dawley female rats, that are naturally estrogen-deficient, have worse stroke outcomes as compared to normally estrous-cycling adult (5-6-month-old) females. Paradoxically, estrogen replacement to this middle-aged group exacerbates stroke outcomes, while it is neuroprotective in adult females. Recent studies reveal an important role for the gut microbiome and gut metabolites in cardiovascular health, including stroke outcomes. To determine whether gut dysbiosis underlies stroke severity in reproductive senescent females, and underlies the anomalous effects of estrogen on stroke, we compared the gut microbiota and gut metabolites pre and post stroke in (a) gonadally intact adult and middle-aged females, (b) in ovariectomized and estrogen-treated (OVX+E) adult and OVX+E middle-aged females, and (c) in middle-aged OVX+E females after fecal microbiome transfer. Our data show significant gut dysbiosis in reproductive senescent females at baseline and after stroke as indicated by an elevated ratio of the major phyla, Firmicutes/Bacteroidetes (F:B), reduced alpha diversity, and significant shifts in beta diversity as compared with adult females. Specific bacterial families were also altered as a result of reproductive aging, as well as gut metabolites, including elevated serum endotoxin levels and decreased short-chain fatty acids (SCFAs), with a concomitant increase in IL-17A, indicating that reproductive senescence significantly affects gut communities under pathologic conditions. Despite the differences in gonadally intact adult and middle-aged females, estrogen-treated ovariectomized (OVX+E) females of either age group displayed no differences in the major phyla, but there was increased abundance in specific bacterial taxa, including Prevotella and Lactobacillus. The SCFA butyrate was significantly reduced at baseline in the middle-aged OVX+E females, while circulating endotoxin LPS were elevated in this group after stroke, suggesting that gut metabolites were differently affected by estrogen treatment in the two age groups. A fecal transfer from adult OVX+E females to middle-aged OVX+E females significantly reduced infarct volume, improved behavioral recovery and transiently reduced IL-17A expression. These data provide the first evidence that microbial gut communities and metabolites are altered by reproductive senescence in female rats at baseline and after stroke, and suggest that estrogen may impact stroke recovery differently in adult and reproductive senescent females due to an age-specific effect on gut microbiota and metabolites.
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17
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Hume AW, Tasker RA. Endothelin-1-Induced Ischemic Damage and Functional Impairment Is Mediated Primarily by NR2B-Containing NMDA Receptors. Neurotox Res 2019; 37:349-355. [PMID: 31797304 DOI: 10.1007/s12640-019-00138-3] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2019] [Revised: 10/30/2019] [Accepted: 11/05/2019] [Indexed: 01/01/2023]
Abstract
Ischemic stroke accounts for 70-80% of stroke cases worldwide and survivors are frequently left with compromising sensorimotor deficits localized to one or more body regions. Most animal models of stroke involve transient or permanent occlusion of one or more major vessels such as the middle cerebral artery and are characterized by widespread damage to cortical and subcortical structures that result in deficits that can confound studies of neuroprotection and neurorehabilitation. Localized microinjections of the vasoconstricting peptide endothelin-1 (ET-1) into specific brain regions are becoming increasingly popular for such studies, but the pharmacology of endothelin-induced ischemic damage is poorly understood. To test the hypothesis that NMDA receptors, and particularly those containing the NR2B subunit, are involved in ET-1-mediated excitotoxicity and functional impairment, male CD1 rats (N = 32) were pre-treated with either the non-competitive NMDA antagonist MK-801 or the NR2B-selective antagonist Ro25-6981 (or vehicle) prior to unilateral microinjections of endothelin-1 into the somatosensory cortex and striatum. Rats were then tested using 4 established tests of sensory and/or motor function over 14 days. Lesion volumes were quantified post-mortem using standard histology and image analysis. Results confirmed reproducible lesions and significant deficits in all tests in vehicle-treated rats that were significantly reduced in both drug groups but were not different between drugs, providing evidence that endothelin-induced ischemic damage is mediated almost exclusively by NR2B-containing NMDA receptors.
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Affiliation(s)
- Andrew W Hume
- Department of Biomedical Sciences, University of Prince Edward Island, 550 University Avenue, Charlottetown, PEI, C1A 4P3, Canada
| | - R Andrew Tasker
- Department of Biomedical Sciences, University of Prince Edward Island, 550 University Avenue, Charlottetown, PEI, C1A 4P3, Canada. .,Translational Neuropsychiatry Unit, Clinical Medicine, Aarhus University, Aarhus, Denmark.
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18
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Microcirculatory Changes in Experimental Models of Stroke and CNS-Injury Induced Immunodepression. Int J Mol Sci 2019; 20:ijms20205184. [PMID: 31635068 PMCID: PMC6834192 DOI: 10.3390/ijms20205184] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2019] [Revised: 10/14/2019] [Accepted: 10/18/2019] [Indexed: 12/17/2022] Open
Abstract
Stroke is the second-leading cause of death globally and the leading cause of disability in adults. Medical complications after stroke, especially infections such as pneumonia, are the leading cause of death in stroke survivors. Systemic immunodepression is considered to contribute to increased susceptibility to infections after stroke. Different experimental models have contributed significantly to the current knowledge of stroke pathophysiology and its consequences. Each model causes different changes in the cerebral microcirculation and local inflammatory responses after ischemia. The vast majority of studies which focused on the peripheral immune response to stroke employed the middle cerebral artery occlusion method. We review various experimental stroke models with regard to microcirculatory changes and discuss the impact on local and peripheral immune response for studies of CNS-injury (central nervous system injury) induced immunodepression.
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19
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Rodent Models of Developmental Ischemic Stroke for Translational Research: Strengths and Weaknesses. Neural Plast 2019; 2019:5089321. [PMID: 31093271 PMCID: PMC6476045 DOI: 10.1155/2019/5089321] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2018] [Revised: 12/19/2018] [Accepted: 02/06/2019] [Indexed: 12/25/2022] Open
Abstract
Cerebral ischemia can occur at any stage in life, but clinical consequences greatly differ depending on the developmental stage of the affected brain structures. Timing of the lesion occurrence seems to be critical, as it strongly interferes with neuronal circuit development and determines the way spontaneous plasticity takes place. Translational stroke research requires the use of animal models as they represent a reliable tool to understand the pathogenic mechanisms underlying the generation, progression, and pathological consequences of a stroke. Moreover, in vivo experiments are instrumental to investigate new therapeutic strategies and the best temporal window of intervention. Differently from adults, very few models of the human developmental stroke have been characterized, and most of them have been established in rodents. The models currently used provide a better understanding of the molecular factors involved in the effects of ischemia; however, they still hold many limitations due to matching developmental stages across different species and the complexity of the human disorder that hardly can be described by segregated variables. In this review, we summarize the key factors contributing to neonatal brain vulnerability to ischemic strokes and we provide an overview of the advantages and limitations of the currently available models to recapitulate different aspects of the human developmental stroke.
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20
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Meadows KL. Experimental models of focal and multifocal cerebral ischemia: a review. Rev Neurosci 2018; 29:661-674. [PMID: 29397392 DOI: 10.1515/revneuro-2017-0076] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2017] [Accepted: 11/26/2017] [Indexed: 02/07/2023]
Abstract
Rodent and rabbit stroke models have been instrumental in our current understanding of stroke pathophysiology; however, translational failure is a significant problem in preclinical ischemic stroke research today. There are a number of different focal cerebral ischemia models that vary in their utility, pathophysiology of causing disease, and their response to treatments. Unfortunately, despite active preclinical research using these models, treatment options for ischemic stroke have not significantly advanced since the food and drug administration approval of tissue plasminogen activator in 1996. This review aims to summarize current stroke therapies, the preclinical experimental models used to help develop stroke therapies, as well as their advantages and limitations. In addition, this review discusses the potential for naturally occurring canine ischemic stroke models to compliment current preclinical models and to help bridge the translational gap between small mammal models and human clinical trials.
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Affiliation(s)
- Kristy L Meadows
- Cummings School of Veterinary Medicine, Tufts University, 200 Westboro Road, Grafton, MA 01536, USA
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21
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Bazzigaluppi P, Adams C, Koletar MM, Dorr A, Pikula A, Carlen PL, Stefanovic B. Oophorectomy Reduces Estradiol Levels and Long-Term Spontaneous Neurovascular Recovery in a Female Rat Model of Focal Ischemic Stroke. Front Mol Neurosci 2018; 11:338. [PMID: 30271324 PMCID: PMC6146137 DOI: 10.3389/fnmol.2018.00338] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2018] [Accepted: 08/28/2018] [Indexed: 12/31/2022] Open
Abstract
Although epidemiological evidence suggests significant sex and gender-based differences in stroke risk and recovery, females have been widely under-represented in preclinical stroke research. The neurovascular sequelae of brain ischemia in females, in particular, are largely uncertain. We set out to address this gap by a multimodal in vivo study of neurovascular recovery from endothelin-1 model of cortical focal-stroke in sham vs. ovariectomized female rats. Three weeks post ischemic insult, sham operated females recapitulated the phenotype previously reported in male rats in this model, of normalized resting perfusion but sustained peri-lesional cerebrovascular hyperreactivity. In contrast, ovariectomized (Ovx) females showed reduced peri-lesional resting blood flow, and elevated cerebrovascular responsivity to hypercapnia in the peri-lesional and contra-lateral cortices. Electrophysiological recordings showed an attenuation of theta to low-gamma phase-amplitude coupling in the peri-lesional tissue of Ovx animals, despite relative preservation of neuronal power. Further, this chronic stage neuronal network dysfunction was inversely correlated with serum estradiol concentration. Our pioneering data demonstrate dramatic differences in spontaneous recovery in the neurovascular unit between Ovx and Sham females in the chronic stage of stroke, underscoring the importance of considering hormonal-dependent aspects of the ischemic sequelae in the development of novel therapeutic approaches and patient recruitment in clinical trials.
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Affiliation(s)
- Paolo Bazzigaluppi
- Sunnybrook Research Institute, Sunnybrook Health Sciences Centre, Toronto, ON, Canada
| | - Conner Adams
- Sunnybrook Research Institute, Sunnybrook Health Sciences Centre, Toronto, ON, Canada
| | - Margaret M Koletar
- Sunnybrook Research Institute, Sunnybrook Health Sciences Centre, Toronto, ON, Canada
| | - Adrienne Dorr
- Sunnybrook Research Institute, Sunnybrook Health Sciences Centre, Toronto, ON, Canada
| | - Aleksandra Pikula
- Adult Vascular Neurology, Toronto Western Hospital, Toronto, ON, Canada
| | - Peter L Carlen
- Fundamental Neurobiology, Krembil Research Institute, Toronto, ON, Canada
| | - Bojana Stefanovic
- Sunnybrook Research Institute, Sunnybrook Health Sciences Centre, Toronto, ON, Canada.,Department of Medical Biophysics, University of Toronto, Toronto, ON, Canada
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22
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Bazzigaluppi P, Lake EM, Beckett TL, Koletar MM, Weisspapir I, Heinen S, Mester J, Lai A, Janik R, Dorr A, McLaurin J, Stanisz GJ, Carlen PL, Stefanovic B. Imaging the Effects of β-Hydroxybutyrate on Peri-Infarct Neurovascular Function and Metabolism. Stroke 2018; 49:2173-2181. [DOI: 10.1161/strokeaha.118.020586] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Affiliation(s)
- Paolo Bazzigaluppi
- From the Physical Sciences Platform (P.B., E.M.L., T.L.B., M.M.K., I.W., J.M., R.J., A.D., G.J.S., B.S.)
- Sunnybrook Research Institute, Toronto, Canada; Fundamental Neurobiology, Krembil Research Institute, Toronto, Canada (P.B., I.W., P.L.C.)
| | - Evelyn M. Lake
- From the Physical Sciences Platform (P.B., E.M.L., T.L.B., M.M.K., I.W., J.M., R.J., A.D., G.J.S., B.S.)
| | - Tina L. Beckett
- From the Physical Sciences Platform (P.B., E.M.L., T.L.B., M.M.K., I.W., J.M., R.J., A.D., G.J.S., B.S.)
| | - Margaret M. Koletar
- From the Physical Sciences Platform (P.B., E.M.L., T.L.B., M.M.K., I.W., J.M., R.J., A.D., G.J.S., B.S.)
| | - Iliya Weisspapir
- From the Physical Sciences Platform (P.B., E.M.L., T.L.B., M.M.K., I.W., J.M., R.J., A.D., G.J.S., B.S.)
- Sunnybrook Research Institute, Toronto, Canada; Fundamental Neurobiology, Krembil Research Institute, Toronto, Canada (P.B., I.W., P.L.C.)
| | | | - James Mester
- From the Physical Sciences Platform (P.B., E.M.L., T.L.B., M.M.K., I.W., J.M., R.J., A.D., G.J.S., B.S.)
- Biological Sciences (J.M.)
| | - Aaron Lai
- Department of Laboratory Medicine and Pathobiology (A.L., J.M.)
| | - Rafal Janik
- From the Physical Sciences Platform (P.B., E.M.L., T.L.B., M.M.K., I.W., J.M., R.J., A.D., G.J.S., B.S.)
- Department of Medical Biophysics (J.M., R.J., G.J.S., B.S.), University of Toronto, Canada
| | - Adrienne Dorr
- From the Physical Sciences Platform (P.B., E.M.L., T.L.B., M.M.K., I.W., J.M., R.J., A.D., G.J.S., B.S.)
| | - JoAnne McLaurin
- Department of Laboratory Medicine and Pathobiology (A.L., J.M.)
- Department of Medical Biophysics (J.M., R.J., G.J.S., B.S.), University of Toronto, Canada
| | - Greg J. Stanisz
- From the Physical Sciences Platform (P.B., E.M.L., T.L.B., M.M.K., I.W., J.M., R.J., A.D., G.J.S., B.S.)
- Department of Medical Biophysics (J.M., R.J., G.J.S., B.S.), University of Toronto, Canada
| | - Peter L. Carlen
- Sunnybrook Research Institute, Toronto, Canada; Fundamental Neurobiology, Krembil Research Institute, Toronto, Canada (P.B., I.W., P.L.C.)
| | - Bojana Stefanovic
- From the Physical Sciences Platform (P.B., E.M.L., T.L.B., M.M.K., I.W., J.M., R.J., A.D., G.J.S., B.S.)
- Department of Medical Biophysics (J.M., R.J., G.J.S., B.S.), University of Toronto, Canada
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23
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Sun Y, Sun X, Qu H, Zhao S, Xiao T, Zhao C. Neuroplasticity and behavioral effects of fluoxetine after experimental stroke. Restor Neurol Neurosci 2018; 35:457-468. [PMID: 28854520 DOI: 10.3233/rnn-170725] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
The brain can undergo self-repair and has the ability to compensate for functions lost after a stroke. The plasticity of the ischemic brain is influenced by several factors including aging and pharmacotherapy. Fluoxetine is an antidepressant which enhances serotonergic neurotransmission through selective inhibition of neuronal reuptake of serotonin. In clinical practice, fluoxetine alleviates the symptoms of post-stroke depression (PSD), helps motor recovery in stroke patients. In animal experiments, chronic administration of fluoxetine induces increased excitability of mature granule cells (GCs), enhancing axonal and dendritic reorganization, as well as promoting neurogenesis or angiogenesis in the dentate gurus (DG), but the effect of fluoxetine in the subventricular zone (SVZ) remains controversial. Meanwhile, chronic treatment with fluoxetine did not reverse age-dependent suppression of proliferation cells in the DG. Interestingly, although fluoxetine has been found to enhance neurogenesis in the DG in stroke rats, this property is not consistent with the behavioral recovery. More studies into this issue will be required to reveal how to translate enhanced neuronal plasticity into behavioral benefits. This review provides an update of the current knowledge about the neurogenesis and the fate of the newly generated cells after the use of fluoxetine, as well as its ability to promote a behavioral recovery after stroke in clinical and experimental results and attempts to define the therapeutic properties of fluoxetine in regenerative neuroscience.
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Affiliation(s)
- Yefei Sun
- Gastrointestinal Surgery, The First Hospital of China Medical University, Shenyang, China
| | - Xiaoyu Sun
- Department of Neurology, The People's Hospital of Liaoning Province, Shenyang, China
| | - Huiling Qu
- Department of Neurology, The People's Hospital of Liaoning Province, Shenyang, China
| | - Shanshan Zhao
- Neurology, The First Hospital of China Medical University, Shenyang, China
| | - Ting Xiao
- Dermatology, The First Hospital of China Medical University, Shenyang, China.,Key Laboratory of Immunodermatology, Ministry of Health, Ministry of Education, Shenyang, China
| | - Chuansheng Zhao
- Neurology, The First Hospital of China Medical University, Shenyang, China
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24
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Abeysinghe HCS, Roulston CL. A Complete Guide to Using the Endothelin-1 Model of Stroke in Conscious Rats for Acute and Long-Term Recovery Studies. Methods Mol Biol 2018; 1717:115-133. [PMID: 29468588 DOI: 10.1007/978-1-4939-7526-6_10] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
Multiple methods exist to model permanent and transient ischemia under anesthesia in animals, however most human strokes occur while conscious. The use of endothelin-1 as a vasoconstrictor applied to the perivascular surface of the middle cerebral artery is one of the only methods for inducing stroke in conscious animals. Here, we describe standard operating procedures for stereotaxic placement of an ET-1 guide probe above the middle cerebral artery, induction of stroke in conscious rats, predictive outcome scoring during stroke, and neurological behavioral tests that we use to monitor transient and continuing deficits. The inclusion of long term neurological assessment is of particular importance when taking into consideration the effects of stroke on brain remodeling.
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Affiliation(s)
- Hima C S Abeysinghe
- Department of Medicine, University of Melbourne, St Vincent's Campus, Fitzroy, VIC, Australia
| | - Carli L Roulston
- Department of Medicine, University of Melbourne, St Vincent's Campus, Fitzroy, VIC, Australia.
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25
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Engler-Chiurazzi EB, Brown CM, Povroznik JM, Simpkins JW. Estrogens as neuroprotectants: Estrogenic actions in the context of cognitive aging and brain injury. Prog Neurobiol 2017; 157:188-211. [PMID: 26891883 PMCID: PMC4985492 DOI: 10.1016/j.pneurobio.2015.12.008] [Citation(s) in RCA: 107] [Impact Index Per Article: 15.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2015] [Revised: 11/06/2015] [Accepted: 12/10/2015] [Indexed: 12/30/2022]
Abstract
There is ample empirical evidence to support the notion that the biological impacts of estrogen extend beyond the gonads to other bodily systems, including the brain and behavior. Converging preclinical findings have indicated a neuroprotective role for estrogen in a variety of experimental models of cognitive function and brain insult. However, the surprising null or even detrimental findings of several large clinical trials evaluating the ability of estrogen-containing hormone treatments to protect against age-related brain changes and insults, including cognitive aging and brain injury, led to hesitation by both clinicians and patients in the use of exogenous estrogenic treatments for nervous system outcomes. That estrogen-containing therapies are used by tens of millions of women for a variety of health-related applications across the lifespan has made identifying conditions under which benefits with estrogen treatment will be realized an important public health issue. Here we provide a summary of the biological actions of estrogen and estrogen-containing formulations in the context of aging, cognition, stroke, and traumatic brain injury. We have devoted special attention to highlighting the notion that estrogen appears to be a conditional neuroprotectant whose efficacy is modulated by several interacting factors. By developing criteria standards for desired beneficial peripheral and neuroprotective outcomes among unique patient populations, we can optimize estrogen treatments for attenuating the consequences of, and perhaps even preventing, cognitive aging and brain injury.
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Affiliation(s)
- E B Engler-Chiurazzi
- Center for Basic and Translational Stroke Research, West Virginia University, Morgantown, WV 26506, United States; Department of Physiology and Pharmacology, West Virginia University, Morgantown, WV 26506, United States.
| | - C M Brown
- Center for Basic and Translational Stroke Research, West Virginia University, Morgantown, WV 26506, United States; Department of Neurobiology and Anatomy, West Virginia University, Morgantown, WV 26506, United States.
| | - J M Povroznik
- Center for Basic and Translational Stroke Research, West Virginia University, Morgantown, WV 26506, United States; Department of Pediatrics, West Virginia University, Morgantown, WV 26506, United States.
| | - J W Simpkins
- Center for Basic and Translational Stroke Research, West Virginia University, Morgantown, WV 26506, United States; Department of Physiology and Pharmacology, West Virginia University, Morgantown, WV 26506, United States.
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26
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Wei L, Wei ZZ, Jiang MQ, Mohamad O, Yu SP. Stem cell transplantation therapy for multifaceted therapeutic benefits after stroke. Prog Neurobiol 2017; 157:49-78. [PMID: 28322920 PMCID: PMC5603356 DOI: 10.1016/j.pneurobio.2017.03.003] [Citation(s) in RCA: 102] [Impact Index Per Article: 14.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2016] [Revised: 01/30/2017] [Accepted: 03/05/2017] [Indexed: 02/06/2023]
Abstract
One of the exciting advances in modern medicine and life science is cell-based neurovascular regeneration of damaged brain tissues and repair of neuronal structures. The progress in stem cell biology and creation of adult induced pluripotent stem (iPS) cells has significantly improved basic and pre-clinical research in disease mechanisms and generated enthusiasm for potential applications in the treatment of central nervous system (CNS) diseases including stroke. Endogenous neural stem cells and cultured stem cells are capable of self-renewal and give rise to virtually all types of cells essential for the makeup of neuronal structures. Meanwhile, stem cells and neural progenitor cells are well-known for their potential for trophic support after transplantation into the ischemic brain. Thus, stem cell-based therapies provide an attractive future for protecting and repairing damaged brain tissues after injury and in various disease states. Moreover, basic research on naïve and differentiated stem cells including iPS cells has markedly improved our understanding of cellular and molecular mechanisms of neurological disorders, and provides a platform for the discovery of novel drug targets. The latest advances indicate that combinatorial approaches using cell based therapy with additional treatments such as protective reagents, preconditioning strategies and rehabilitation therapy can significantly improve therapeutic benefits. In this review, we will discuss the characteristics of cell therapy in different ischemic models and the application of stem cells and progenitor cells as regenerative medicine for the treatment of stroke.
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Affiliation(s)
- Ling Wei
- Laboratories of Stem Cell Biology and Regenerative Medicine, Department of Neurology, Experimental Research Center and Neurological Disease Center, Beijing Friendship Hospital, Capital Medical University, Beijing 100050, China; Department of Anesthesiology, Emory University School of Medicine, Atlanta, GA 30322, USA; Department of Neurology, Emory University School of Medicine, Atlanta, GA 30322, USA
| | - Zheng Z Wei
- Department of Anesthesiology, Emory University School of Medicine, Atlanta, GA 30322, USA
| | - Michael Qize Jiang
- Department of Anesthesiology, Emory University School of Medicine, Atlanta, GA 30322, USA
| | - Osama Mohamad
- Department of Anesthesiology, Emory University School of Medicine, Atlanta, GA 30322, USA
| | - Shan Ping Yu
- Laboratories of Stem Cell Biology and Regenerative Medicine, Department of Neurology, Experimental Research Center and Neurological Disease Center, Beijing Friendship Hospital, Capital Medical University, Beijing 100050, China; Department of Anesthesiology, Emory University School of Medicine, Atlanta, GA 30322, USA.
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Potential Therapeutic Mechanisms and Tracking of Transplanted Stem Cells: Implications for Stroke Treatment. Stem Cells Int 2017; 2017:2707082. [PMID: 28904531 PMCID: PMC5585684 DOI: 10.1155/2017/2707082] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2017] [Revised: 07/08/2017] [Accepted: 07/30/2017] [Indexed: 02/06/2023] Open
Abstract
Stem cell therapy is a promising potential therapeutic strategy to treat cerebral ischemia in preclinical and clinical trials. Currently proposed treatments for stroke employing stem cells include the replacement of lost neurons and integration into the existing host circuitry, the release of growth factors to support and promote endogenous repair processes, and the secretion of extracellular vesicles containing proteins, noncoding RNA, or DNA to regulate gene expression in recipient cells and achieve immunomodulation. Progress has been made to elucidate the precise mechanisms underlying stem cell therapy and the homing, migration, distribution, and differentiation of transplanted stem cells in vivo using various imaging modalities. Noninvasive and safe tracer agents with high sensitivity and image resolution must be combined with long-term monitoring using imaging technology to determine the optimal therapy for stroke in terms of administration route, dosage, and timing. This review discusses potential therapeutic mechanisms of stem cell transplantation for the treatment of stroke and the limitations of current therapies. Methods to label transplanted cells and existing imaging systems for stem cell labeling and in vivo tracking will also be discussed.
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Weber RA, Chan CH, Nie X, Maggioncalda E, Valiulis G, Lauer A, Hui ES, Jensen JH, Adkins DL. Sensitivity of diffusion MRI to perilesional reactive astrogliosis in focal ischemia. NMR IN BIOMEDICINE 2017; 30:10.1002/nbm.3717. [PMID: 28272771 PMCID: PMC5759343 DOI: 10.1002/nbm.3717] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/23/2016] [Revised: 01/04/2017] [Accepted: 01/31/2017] [Indexed: 06/06/2023]
Abstract
Reactive astrogliosis is a response to injury in the central nervous system that plays an essential role in inflammation and tissue repair. It is characterized by hypertrophy of astrocytes, alterations in astrocyte gene expression and astrocyte proliferation. Reactive astrogliosis occurs in multiple neuropathologies, including stroke, traumatic brain injury and Alzheimer's disease, and it has been proposed as a possible source of the changes in diffusion magnetic resonance imaging (dMRI) metrics observed with these diseases. In this study, the sensitivity of dMRI to reactive astrogliosis was tested in an animal model of focal acute and subacute ischemia induced by the vasoconstricting peptide, endothelin-1. Reactive astrogliosis in perilesional cortex was quantified by calculating the astrocyte surface density as determined with a glial fibrillary acidic protein (GFAP) antibody, whereas perilesional diffusion changes were measured in vivo with diffusional kurtosis imaging. We found substantial changes in the surface density of GFAP-positive astrocyte processes and modest changes in dMRI metrics in the perilesional motor cortex following stroke. Although there are time point-specific correlations between dMRI and histological measures, there is no definitive evidence for a causal relationship.
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Affiliation(s)
- Rachel A. Weber
- Department of Neuroscience, Medical University of South Carolina, Charleston, South Carolina, USA
| | - Clifford H. Chan
- Department of Radiology and Radiological Science, Medical University of South Carolina, Charleston, South Carolina, USA
- Center for Biomedical Imaging, Medical University of South Carolina, Charleston, South Carolina, USA
| | - Xingju Nie
- Center for Biomedical Imaging, Medical University of South Carolina, Charleston, South Carolina, USA
| | - Emily Maggioncalda
- Department of Neuroscience, Medical University of South Carolina, Charleston, South Carolina, USA
| | - Grace Valiulis
- Department of Neuroscience, Medical University of South Carolina, Charleston, South Carolina, USA
| | - Abigail Lauer
- Department of Public Health Sciences, Medical University of South Carolina, Charleston, South Carolina, USA
| | - Edward S. Hui
- Department of Diagnostic Radiology, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Pokfulam, Hong Kong SAR, China
| | - Jens H. Jensen
- Department of Radiology and Radiological Science, Medical University of South Carolina, Charleston, South Carolina, USA
- Center for Biomedical Imaging, Medical University of South Carolina, Charleston, South Carolina, USA
| | - DeAnna L. Adkins
- Department of Neuroscience, Medical University of South Carolina, Charleston, South Carolina, USA
- Center for Biomedical Imaging, Medical University of South Carolina, Charleston, South Carolina, USA
- Department of Health Science and Research, Medical University of South Carolina, Charleston, South Carolina, USA
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29
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Dai P, Huang H, Zhang L, He J, Zhao X, Yang F, Zhao N, Yang J, Ge L, Lin Y, Yu H, Wang J. A pilot study on transient ischemic stroke induced with endothelin-1 in the rhesus monkeys. Sci Rep 2017; 7:45097. [PMID: 28358140 PMCID: PMC5372164 DOI: 10.1038/srep45097] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2016] [Accepted: 02/17/2017] [Indexed: 12/25/2022] Open
Abstract
Endothelin-1 (ET-1), a vasoconstrictor, has recently been used to induce focal ischemia in rodents and marmoset monkeys. The rhesus monkey, however, has numerous advantages to the rodent and marmoset that make it a superior and irreplaceable animal model for studying stroke in the brain. In the present study, after mapping the preferred hand representation in two healthy male monkeys with intracortical micro-stimulation, ET-1 was microinjected into the contralateral motor cortex (M1) to its preferred hand. The monkeys had been trained in three manual dexterity tasks before the microinjection and were tested for these tasks following the ET-1 injection. Brain Magnetic Resonance Imaging scans were performed 1, 7, 14 and 28 days post ischemia. It was found that ET-1 impaired the manual dexterity of the monkeys in the vertical slot and rotating Brinkman board tasks 3–8 days after the injection. Brain imaging found that severe edema was present 7 days after the focal ischemia. This data suggest that ET-1 can induce transient ischemic stroke in rhesus monkey and that ET-1 induced focal ischemia in non-human primates is a potential model to study the mechanism of stroke and brain repair after stroke.
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Affiliation(s)
- PeiMin Dai
- Key Laboratory of Animal Models and Human Disease Mechanisms of the Chinese Academy of Sciences &Yunnan Province, Kunming Primates Research Center, Kunming Institute of Zoology, Chinese Academy of Sciences, Kunming, China.,Department of Neurosurgery, First People's Hospital of Honghe State, Honghe, China
| | - Hui Huang
- Key Laboratory of Animal Models and Human Disease Mechanisms of the Chinese Academy of Sciences &Yunnan Province, Kunming Primates Research Center, Kunming Institute of Zoology, Chinese Academy of Sciences, Kunming, China.,Department of Neurosurgery, Second Affiliated Hospital of Nanchang University, Nanchang, China
| | - Lin Zhang
- Key Laboratory of Animal Models and Human Disease Mechanisms of the Chinese Academy of Sciences &Yunnan Province, Kunming Primates Research Center, Kunming Institute of Zoology, Chinese Academy of Sciences, Kunming, China.,Department of Neurosurgery, Center People's Hospital of Zhumadian State, Zhumadian, China.,Second Department of Neurosurgery, First Affiliated Hospital of Kunming Medical University, Kunming, China
| | - Jing He
- Yunnan Key Laboratory of Primate Biomedical Research Institute of Primate Translational Medicine, Kunming University of Science and Technology, Kunming, China
| | - XuDong Zhao
- State Key Laboratory of Brain and Cognitive Science, Institute of Biophysics, Chinese Academy of Sciences, Beijing, China
| | - FuHan Yang
- Key Laboratory of Animal Models and Human Disease Mechanisms of the Chinese Academy of Sciences &Yunnan Province, Kunming Primates Research Center, Kunming Institute of Zoology, Chinese Academy of Sciences, Kunming, China
| | - Ning Zhao
- Second Department of Neurosurgery, First Affiliated Hospital of Kunming Medical University, Kunming, China
| | - JianZhen Yang
- Key Laboratory of Animal Models and Human Disease Mechanisms of the Chinese Academy of Sciences &Yunnan Province, Kunming Primates Research Center, Kunming Institute of Zoology, Chinese Academy of Sciences, Kunming, China
| | - LongJiao Ge
- Key Laboratory of Animal Models and Human Disease Mechanisms of the Chinese Academy of Sciences &Yunnan Province, Kunming Primates Research Center, Kunming Institute of Zoology, Chinese Academy of Sciences, Kunming, China
| | - Yu Lin
- Key Laboratory of Animal Models and Human Disease Mechanisms of the Chinese Academy of Sciences &Yunnan Province, Kunming Primates Research Center, Kunming Institute of Zoology, Chinese Academy of Sciences, Kunming, China
| | - HuaLin Yu
- Second Department of Neurosurgery, First Affiliated Hospital of Kunming Medical University, Kunming, China
| | - JianHong Wang
- Key Laboratory of Animal Models and Human Disease Mechanisms of the Chinese Academy of Sciences &Yunnan Province, Kunming Primates Research Center, Kunming Institute of Zoology, Chinese Academy of Sciences, Kunming, China
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Potent neuroprotection after stroke afforded by a double-knot spider-venom peptide that inhibits acid-sensing ion channel 1a. Proc Natl Acad Sci U S A 2017; 114:3750-3755. [PMID: 28320941 DOI: 10.1073/pnas.1614728114] [Citation(s) in RCA: 146] [Impact Index Per Article: 20.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Stroke is the second-leading cause of death worldwide, yet there are no drugs available to protect the brain from stroke-induced neuronal injury. Acid-sensing ion channel 1a (ASIC1a) is the primary acid sensor in mammalian brain and a key mediator of acidosis-induced neuronal damage following cerebral ischemia. Genetic ablation and selective pharmacologic inhibition of ASIC1a reduces neuronal death following ischemic stroke in rodents. Here, we demonstrate that Hi1a, a disulfide-rich spider venom peptide, is highly neuroprotective in a focal model of ischemic stroke. Nuclear magnetic resonance structural studies reveal that Hi1a comprises two homologous inhibitor cystine knot domains separated by a short, structurally well-defined linker. In contrast with known ASIC1a inhibitors, Hi1a incompletely inhibits ASIC1a activation in a pH-independent and slowly reversible manner. Whole-cell, macropatch, and single-channel electrophysiological recordings indicate that Hi1a binds to and stabilizes the closed state of the channel, thereby impeding the transition into a conducting state. Intracerebroventricular administration to rats of a single small dose of Hi1a (2 ng/kg) up to 8 h after stroke induction by occlusion of the middle cerebral artery markedly reduced infarct size, and this correlated with improved neurological and motor function, as well as with preservation of neuronal architecture. Thus, Hi1a is a powerful pharmacological tool for probing the role of ASIC1a in acid-mediated neuronal injury and various neurological disorders, and a promising lead for the development of therapeutics to protect the brain from ischemic injury.
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Abstract
This article highlights the emerging therapeutic potential of specific epigenetic modulators as promising antiepileptogenic or disease-modifying agents for curing epilepsy. Currently, there is an unmet need for antiepileptogenic agents that truly prevent the development of epilepsy in people at risk. There is strong evidence that epigenetic signaling, which exerts high fidelity regulation of gene expression, plays a crucial role in the pathophysiology of epileptogenesis and chronic epilepsy. These modifications are not hard-wired into the genome and are constantly reprogrammed by environmental influences. The potential epigenetic mechanisms, including histone modifications, DNA methylation, microRNA-based transcriptional control, and bromodomain reading activity, can drastically alter the neuronal gene expression profile by exerting their summative effects in a coordinated fashion. Such an epigenetic intervention appears more rational strategy for preventing epilepsy because it targets the primary pathway that initially triggers the numerous downstream cellular and molecular events mediating epileptogenesis. Among currently approved epigenetic drugs, the majority are anticancer drugs with well-established profiles in clinical trials and practice. Evidence from preclinical studies supports the premise that these drugs may be applied to a wide range of brain disorders. Targeting histone deacetylation by inhibiting histone deacetylase enzymes appears to be one promising epigenetic therapy since certain inhibitors have been shown to prevent epileptogenesis in animal models. However, developing neuronal specific epigenetic modulators requires rational, pathophysiology-based optimization to efficiently intercept the upstream pathways in epileptogenesis. Overall, epigenetic agents have been well positioned as new frontier tools towards the national goal of curing epilepsy.
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32
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Neurovascular unit remodelling in the subacute stage of stroke recovery. Neuroimage 2017; 146:869-882. [DOI: 10.1016/j.neuroimage.2016.09.016] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2016] [Revised: 08/31/2016] [Accepted: 09/08/2016] [Indexed: 01/19/2023] Open
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Gibbs WS, Weber RA, Schnellmann RG, Adkins DL. Disrupted mitochondrial genes and inflammation following stroke. Life Sci 2016; 166:139-148. [PMID: 27693381 DOI: 10.1016/j.lfs.2016.09.021] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2016] [Revised: 09/08/2016] [Accepted: 09/26/2016] [Indexed: 12/26/2022]
Abstract
AIMS Determine the subacute time course of mitochondria disruption, cell death, and inflammation in a rat model of unilateral motor cortical ischemic stroke. MAIN METHODS Rats received unilateral ischemia of the motor cortex and were tested on behavioral tasks to determine impairments. Animals were euthanized at 24h, 72h and 144h and mRNA expression of key mitochondria proteins and indicators of inflammation, apoptosis and potential regenerative processes in ipsilesion cortex and striatum, using RT-qPCR. Mitochondrial proteins were examined at 144h using immunoblot analysis. KEY FINDINGS Rats with stroke induced-behavioral deficits had sustained, 144h post-lesion, decreases in mitochondrial-encoded electron transport chain proteins NADH dehydrogenase subunit-1 and cytochrome c oxidase subunit-1 (mRNA and protein) and mitochondrial DNA content in perilesion motor and sensory cortex. Uncoupling-protein-2 gene expression, but not superoxide dismutase-2, remained elevated in ipsilateral cortex and striatum at this time. Cortical inflammatory cytokine, interleukin-6, was increased early and was followed by increased macrophage marker F4/80 after stroke. Cleaved caspase-3 activation was elevated in cortex and growth associated protein-43 was elevated in the cortex and striatum six days post-lesion. SIGNIFICANCE We identified a relationship between three disrupted pathways, (1) sustained loss of mitochondrial proteins and mitochondrial DNA copy number in the cortex linked to decreased mitochondrial gene transcription; (2) early inflammatory response mediated by interleukin- 6 followed by macrophages; (3) apoptosis in conjunction with the activation of regenerative pathways. The stroke-induced spatial and temporal profiles lay the foundation to target pharmacological therapeutics to these three pathways.
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Affiliation(s)
- Whitney S Gibbs
- Department of Drug Discovery and Biomedical Sciences, Medical University of South Carolina, Charleston SC, United States
| | - Rachel A Weber
- Department of Neuroscience, Medical University of South Carolina, Charleston SC, United States
| | - Rick G Schnellmann
- Ralph H. Johnson VA Medical Center, Charleston, SC, United States; Department of Pharmacy & Toxicology, College of Pharmacy, University of Arizona, Tucson, AZ, United States.
| | - DeAnna L Adkins
- Department of Neuroscience, Medical University of South Carolina, Charleston SC, United States; Center of Biomedical Imaging, Medical University of South Carolina, Charleston SC, United States; Health Sciences and Research, College of Health Professions, Medical University of South Carolina, Charleston, SC, United States.
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34
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An Evidence-Based Review of Related Metabolites and Metabolic Network Research on Cerebral Ischemia. OXIDATIVE MEDICINE AND CELLULAR LONGEVITY 2016; 2016:9162074. [PMID: 27274780 PMCID: PMC4871976 DOI: 10.1155/2016/9162074] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/30/2015] [Revised: 03/27/2016] [Accepted: 04/14/2016] [Indexed: 11/17/2022]
Abstract
In recent years, metabolomics analyses have been widely applied to cerebral ischemia research. This paper introduces the latest proceedings of metabolomics research on cerebral ischemia. The main techniques, models, animals, and biomarkers of cerebral ischemia will be discussed. With analysis help from the MBRole website and the KEGG database, the altered metabolites in rat cerebral ischemia were used for metabolic pathway enrichment analyses. Our results identify the main metabolic pathways that are related to cerebral ischemia and further construct a metabolic network. These results will provide useful information for elucidating the pathogenesis of cerebral ischemia, as well as the discovery of cerebral ischemia biomarkers.
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35
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Lake EMR, Chaudhuri J, Thomason L, Janik R, Ganguly M, Brown M, McLaurin J, Corbett D, Stanisz GJ, Stefanovic B. The effects of delayed reduction of tonic inhibition on ischemic lesion and sensorimotor function. J Cereb Blood Flow Metab 2015; 35:1601-9. [PMID: 25966952 PMCID: PMC4640317 DOI: 10.1038/jcbfm.2015.86] [Citation(s) in RCA: 51] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/10/2014] [Revised: 03/25/2015] [Accepted: 03/30/2015] [Indexed: 02/02/2023]
Abstract
To aid in development of chronic stage treatments for sensorimotor deficits induced by ischemic stroke, we investigated the effects of GABA antagonism on brain structure and fine skilled reaching in a rat model of focal ischemia induced via cortical microinjections of endothelin-1 (ET-1). Beginning 7 days after stroke, animals were administered a gamma-aminobutyric acid (GABAA) inverse agonist, L-655,708, at a dose low enough to afford α5-GABAA receptor specificity. A week after stroke, the ischemic lesion comprised a small hypointense necrotic core (6±1 mm(3)) surrounded by a large (62±11 mm(3)) hyperintense perilesional region; the skilled reaching ability on the Montoya staircase test was decreased to 34%±2% of the animals' prestroke performance level. On L-655,708 treatment, animals showed a progressive decrease in total stroke volume (13±4 mm(3) per week), with no change in animals receiving placebo. Concomitantly, treated animals' skilled reaching progressively improved by 9%±1% per week, so that after 2 weeks of treatment, these animals performed at 65%±6% of their baseline ability, which was 25%±11% better than animals given placebo. These data indicate beneficial effects of delayed, sustained low-dose GABAA antagonism on neuroanatomic injury and skilled reaching in the chronic stage of stroke recovery in an ET-1 rat model of focal ischemia.
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Affiliation(s)
- Evelyn M R Lake
- Department of Medical Biophysics, University of Toronto, Sunnybrook Health Sciences Centre, Toronto, Ontario, Canada
| | - Joydeep Chaudhuri
- Department of Physical Sciences, Sunnybrook Research Institute, Toronto, Ontario, Canada
| | - Lynsie Thomason
- Department of Physical Sciences, Sunnybrook Research Institute, Toronto, Ontario, Canada
| | - Rafal Janik
- Department of Medical Biophysics, University of Toronto, Sunnybrook Health Sciences Centre, Toronto, Ontario, Canada
- Department of Physical Sciences, Sunnybrook Research Institute, Toronto, Ontario, Canada
| | - Milan Ganguly
- Department of Physical Sciences, Sunnybrook Research Institute, Toronto, Ontario, Canada
| | - Mary Brown
- Department of Biological Sciences, Sunnybrook Research Institute, Toronto, Ontario, Canada
| | - JoAnne McLaurin
- Department of Biological Sciences, Sunnybrook Research Institute, Toronto, Ontario, Canada
- Hurvitz Brain Sciences Research, Sunnybrook Research Institute, Toronto, Ontario, Canada
- Department of Laboratory Medicine and Pathobiology, University of Toronto, Toronto, Ontario, Canada
| | - Dale Corbett
- Department of Medicine, University of Toronto, Toronto, Ontario, Canada
- Department of Cellular & Molecular Medicine, University of Ottawa, Ottawa, Ontario, Canada
- Heart and Stroke Foundation Canadian Partnership for Stroke Recovery, Ottawa, Ontario, Canada
| | - Greg J Stanisz
- Department of Medical Biophysics, University of Toronto, Sunnybrook Health Sciences Centre, Toronto, Ontario, Canada
- Department of Physical Sciences, Sunnybrook Research Institute, Toronto, Ontario, Canada
- Department of Neurosurgery and Paediatric Neurosurgery, Medical University Lublin, Lublin, Poland
| | - Bojana Stefanovic
- Department of Medical Biophysics, University of Toronto, Sunnybrook Health Sciences Centre, Toronto, Ontario, Canada
- Department of Physical Sciences, Sunnybrook Research Institute, Toronto, Ontario, Canada
- Heart and Stroke Foundation Canadian Partnership for Stroke Recovery, Ottawa, Ontario, Canada
- Department of Neurosurgery and Paediatric Neurosurgery, Medical University Lublin, Lublin, Poland
- Neuropsychopharmacology Research Group, Sunnybrook Research Institute, Toronto, Ontario, Canada
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Evidence for a role of the reticulospinal system in recovery of skilled reaching after cortical stroke: initial results from a model of ischemic cortical injury. Exp Brain Res 2015; 233:3231-51. [PMID: 26231990 DOI: 10.1007/s00221-015-4390-x] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2015] [Accepted: 07/13/2015] [Indexed: 12/25/2022]
Abstract
The purposes of this pilot study were to create a model of focal cortical ischemia in Macaca fascicularis and to explore contributions of the reticulospinal system in recovery of reaching. Endothelin-1 was used to create a focal lesion in the shoulder/elbow representation of left primary motor cortex (M1) of two adult female macaques. Repetitive microstimulation was used to map upper limb motor outputs from right and left cortical motor areas and from the pontomedullary reticular formation (PMRF). In subject 1 with a small lesion and spontaneous recovery, reaching was mildly impaired. Changes were evident in the shoulder/elbow representations of both the lesioned and contralesional M1, and there appeared to be fewer than expected upper limb responses from the left (ipsilesional) PMRF. In subject 2 with a substantial lesion, reaching was severely impaired immediately after the lesion. After 12 weeks of intensive rehabilitative training, reach performance recovered to near-baseline levels, but movement times remained about 50% slower. Surprisingly, the shoulder/elbow representation in the lesioned M1 remained completely absent after recovery, and there was a little change in the contralesional M1. There was a definite difference in motor output patterns for left versus right PMRF for this subject, with an increase in right arm responses from right PMRF and a paucity of left arm responses from left PMRF. The results are consistent with increased reliance on PMRF motor outputs for recovery of voluntary upper limb motor control after significant cortical ischemic injury.
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Fluri F, Schuhmann MK, Kleinschnitz C. Animal models of ischemic stroke and their application in clinical research. DRUG DESIGN DEVELOPMENT AND THERAPY 2015; 9:3445-54. [PMID: 26170628 PMCID: PMC4494187 DOI: 10.2147/dddt.s56071] [Citation(s) in RCA: 242] [Impact Index Per Article: 26.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
This review outlines the most frequently used rodent stroke models and discusses their strengths and shortcomings. Mimicking all aspects of human stroke in one animal model is not feasible because ischemic stroke in humans is a heterogeneous disorder with a complex pathophysiology. The transient or permanent middle cerebral artery occlusion (MCAo) model is one of the models that most closely simulate human ischemic stroke. Furthermore, this model is characterized by reliable and well-reproducible infarcts. Therefore, the MCAo model has been involved in the majority of studies that address pathophysiological processes or neuroprotective agents. Another model uses thromboembolic clots and thus is more convenient for investigating thrombolytic agents and pathophysiological processes after thrombolysis. However, for many reasons, preclinical stroke research has a low translational success rate. One factor might be the choice of stroke model. Whereas the therapeutic responsiveness of permanent focal stroke in humans declines significantly within 3 hours after stroke onset, the therapeutic window in animal models with prompt reperfusion is up to 12 hours, resulting in a much longer action time of the investigated agent. Another major problem of animal stroke models is that studies are mostly conducted in young animals without any comorbidity. These models differ from human stroke, which particularly affects elderly people who have various cerebrovascular risk factors. Choosing the most appropriate stroke model and optimizing the study design of preclinical trials might increase the translational potential of animal stroke models.
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Affiliation(s)
- Felix Fluri
- Department of Neurology, University Clinic Wuerzburg, Wuerzburg, Germany
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38
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Sheng T, Zhang X, Wang S, Zhang J, Lu W, Dai Y. Endothelin-1-induced mini-stroke in the dorsal hippocampus or lateral amygdala results in deficits in learning and memory. J Biomed Res 2015; 29:362-9. [PMID: 26445569 PMCID: PMC4585430 DOI: 10.7555/jbr.29.20150008] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2015] [Revised: 03/29/2015] [Accepted: 04/27/2015] [Indexed: 11/08/2022] Open
Abstract
Functional and structural alterations in brain connectivity associated with brain ischemia have been extensively studied. However, the mechanism whereby local ischemia in deep brain region affect brain functions is still unknown. Here, we first established a mini-stroke model by infusion of endothelin-1 (ET-1) into the dorsal hippocampus or the lateral amygdala, and then investigated how these mini-infarcts affected brain functions associated with these regions. We found that rats with ET-1 infusion showed deficit in recall of contextual fear memory, but not in learning process and recall of tone fear memory. In novel object task, ET-1 in the hippocampus also eliminated object identity memory. ET-1 in the lateral amygdale affected acquisition of fear conditioning and disrupted retention of tone-conditioned fear, but did not impair retention of contextual fear. These findings suggest that ET-1-induced mini-infarct in deep brain area leads to functional deficits in learning and memory associated with these regions.
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Affiliation(s)
- Tao Sheng
- The Center of Metabolic Disease Research
| | - Xueting Zhang
- The Key Laboratory of Developmental Genes and Human Disease, Institute of Life Sciences, Southeast University , Nanjing, Jiangsu 210096 , China
| | - Shaoli Wang
- The Key Laboratory of Developmental Genes and Human Disease, Institute of Life Sciences, Southeast University , Nanjing, Jiangsu 210096 , China
| | - Jingyun Zhang
- The Key Laboratory of Developmental Genes and Human Disease, Institute of Life Sciences, Southeast University , Nanjing, Jiangsu 210096 , China
| | - Wei Lu
- Department of Neurobiology, Nanjing Medical University , Nanjing, Jiangsu 210029 , China ; The Key Laboratory of Developmental Genes and Human Disease, Institute of Life Sciences, Southeast University , Nanjing, Jiangsu 210096 , China
| | - Yifan Dai
- The Center of Metabolic Disease Research
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Nguemeni C, Gomez-Smith M, Jeffers MS, Schuch CP, Corbett D. Time course of neuronal death following endothelin-1 induced focal ischemia in rats. J Neurosci Methods 2015; 242:72-6. [PMID: 25583382 DOI: 10.1016/j.jneumeth.2015.01.005] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2014] [Revised: 12/08/2014] [Accepted: 01/03/2015] [Indexed: 10/24/2022]
Abstract
BACKGROUND Endothelin-1 (ET-1) induced focal ischemia is increasingly being used as a preclinical model of stroke. Here, we described for the first time, the time course of neuronal death and infarct evolution during the first 7 days following ischemia. NEW METHOD We used hematoxylin and eosin (H&E) staining to evaluate infarct progression and Fluoro-Jade C (FJC) to quantify neuronal degeneration at 24, 48, 72h and 7 days after ET-1 injection to the forelimb motor cortex in Sprague-Dawley rats. RESULTS We found that infarct volume and neuronal degeneration are maximal at 24h post-stroke. Neuronal degeneration is also significantly reduced within 7 days of stroke induction. COMPARISON WITH EXISTING METHOD This study is the first to provide a direct evaluation of both infarct volume evolution and neuronal death time course following ET-1 induced focal ischemia in the forelimb motor cortex. CONCLUSION This study describes the short-term time course of neuronal death and brain injury in the ET-1 stroke model, which provides a significant reference when determining the appropriate time to commence neuroprotective or recovery promoting strategies.
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Affiliation(s)
- Carine Nguemeni
- Faculty of Medicine, University of Ottawa, Ottawa, ON, Canada; Canadian Partnership for Stroke Recovery, University of Ottawa, Ottawa, ON, Canada
| | - Mariana Gomez-Smith
- Faculty of Medicine, University of Ottawa, Ottawa, ON, Canada; Canadian Partnership for Stroke Recovery, University of Ottawa, Ottawa, ON, Canada
| | - Matthew S Jeffers
- Faculty of Medicine, University of Ottawa, Ottawa, ON, Canada; Canadian Partnership for Stroke Recovery, University of Ottawa, Ottawa, ON, Canada
| | | | - Dale Corbett
- Faculty of Medicine, University of Ottawa, Ottawa, ON, Canada; Faculty of Medicine, Memorial University of Newfoundland, St. John's, NL, Canada; Faculty of Medicine, University of Toronto, Toronto, ON, Canada; Canadian Partnership for Stroke Recovery, University of Ottawa, Ottawa, ON, Canada.
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40
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Weber RA, Hui ES, Jensen JH, Nie X, Falangola MF, Helpern JA, Adkins DL. Diffusional kurtosis and diffusion tensor imaging reveal different time-sensitive stroke-induced microstructural changes. Stroke 2015; 46:545-50. [PMID: 25563646 DOI: 10.1161/strokeaha.114.006782] [Citation(s) in RCA: 61] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
BACKGROUND AND PURPOSE Diffusion MRI is a promising, clinically feasible imaging technique commonly used to describe white matter changes after stroke. We investigated the sensitivity of diffusion MRI to detect microstructural alterations in gray matter after sensorimotor cortex stroke in adult male rats. METHODS The mean diffusivity (MD) and mean kurtosis of perilesional motor cortex were compared with measures in the contralesional forelimb area of sensorimotor cortex at 2 hours, 24 hours, 72 hours, or 25 days after surgery. MD and mean kurtosis were correlated to the surface densities of glia, dendrites, and axons. RESULTS Perilesional mean kurtosis was increased at 72 hours and 25 days after stroke, whereas MD was no longer different from contralesional sensorimotor cortex at 24 hours after stroke. There was a significant increase in the density of glial processes at 72 hours after stroke in perilesional motor cortex, which correlated with perilesional MD. CONCLUSIONS These data support that mean kurtosis and MD provide different but complimentary information on acute and chronic changes in perilesional cortex. Glia infiltration is associated with pseudonormalization of MD in the perilesional motor cortex at 72 hours after lesion; however, this association is absent 25 days after lesion. These data suggest that there are likely several different, time-specific microstructural changes underlying these 2 complimentary diffusion measures.
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Affiliation(s)
- Rachel A Weber
- From the Department of Neurosciences (R.A.W., M.F.F., J.A.H., D.L.A.), Center for Biomedical Imaging (J.H.J., X.N., M.F.F., J.A.H., D.L.A.), Department of Radiology and Radiological Science (J.H.J., X.N., M.F.F., J.A.H.), and Health Sciences and Research, College of Health Professions (D.L.A.), Medical University of South Carolina, Charleston; and Department of Diagnostic Radiology, University of Hong Kong, Pokfulam, Hong Kong (E.S.H.)
| | - Edward S Hui
- From the Department of Neurosciences (R.A.W., M.F.F., J.A.H., D.L.A.), Center for Biomedical Imaging (J.H.J., X.N., M.F.F., J.A.H., D.L.A.), Department of Radiology and Radiological Science (J.H.J., X.N., M.F.F., J.A.H.), and Health Sciences and Research, College of Health Professions (D.L.A.), Medical University of South Carolina, Charleston; and Department of Diagnostic Radiology, University of Hong Kong, Pokfulam, Hong Kong (E.S.H.)
| | - Jens H Jensen
- From the Department of Neurosciences (R.A.W., M.F.F., J.A.H., D.L.A.), Center for Biomedical Imaging (J.H.J., X.N., M.F.F., J.A.H., D.L.A.), Department of Radiology and Radiological Science (J.H.J., X.N., M.F.F., J.A.H.), and Health Sciences and Research, College of Health Professions (D.L.A.), Medical University of South Carolina, Charleston; and Department of Diagnostic Radiology, University of Hong Kong, Pokfulam, Hong Kong (E.S.H.)
| | - Xingju Nie
- From the Department of Neurosciences (R.A.W., M.F.F., J.A.H., D.L.A.), Center for Biomedical Imaging (J.H.J., X.N., M.F.F., J.A.H., D.L.A.), Department of Radiology and Radiological Science (J.H.J., X.N., M.F.F., J.A.H.), and Health Sciences and Research, College of Health Professions (D.L.A.), Medical University of South Carolina, Charleston; and Department of Diagnostic Radiology, University of Hong Kong, Pokfulam, Hong Kong (E.S.H.)
| | - Maria F Falangola
- From the Department of Neurosciences (R.A.W., M.F.F., J.A.H., D.L.A.), Center for Biomedical Imaging (J.H.J., X.N., M.F.F., J.A.H., D.L.A.), Department of Radiology and Radiological Science (J.H.J., X.N., M.F.F., J.A.H.), and Health Sciences and Research, College of Health Professions (D.L.A.), Medical University of South Carolina, Charleston; and Department of Diagnostic Radiology, University of Hong Kong, Pokfulam, Hong Kong (E.S.H.)
| | - Joseph A Helpern
- From the Department of Neurosciences (R.A.W., M.F.F., J.A.H., D.L.A.), Center for Biomedical Imaging (J.H.J., X.N., M.F.F., J.A.H., D.L.A.), Department of Radiology and Radiological Science (J.H.J., X.N., M.F.F., J.A.H.), and Health Sciences and Research, College of Health Professions (D.L.A.), Medical University of South Carolina, Charleston; and Department of Diagnostic Radiology, University of Hong Kong, Pokfulam, Hong Kong (E.S.H.)
| | - DeAnna L Adkins
- From the Department of Neurosciences (R.A.W., M.F.F., J.A.H., D.L.A.), Center for Biomedical Imaging (J.H.J., X.N., M.F.F., J.A.H., D.L.A.), Department of Radiology and Radiological Science (J.H.J., X.N., M.F.F., J.A.H.), and Health Sciences and Research, College of Health Professions (D.L.A.), Medical University of South Carolina, Charleston; and Department of Diagnostic Radiology, University of Hong Kong, Pokfulam, Hong Kong (E.S.H.).
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Coucha M, Li W, Hafez S, Abdelsaid M, Johnson MH, Fagan SC, Ergul A. SOD1 overexpression prevents acute hyperglycemia-induced cerebral myogenic dysfunction: relevance to contralateral hemisphere and stroke outcomes. Am J Physiol Heart Circ Physiol 2014; 308:H456-66. [PMID: 25552308 DOI: 10.1152/ajpheart.00321.2014] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Admission hyperglycemia (HG) amplifies vascular injury and neurological deficits in acute ischemic stroke, but the mechanisms remain controversial. We recently reported that ischemia-reperfusion (I/R) injury impairs the myogenic response in both hemispheres via increased nitration. However, whether HG amplifies contralateral myogenic dysfunction and whether loss of tone in the contralateral hemisphere contributes to stroke outcomes remain to be determined. Our hypothesis was that contralateral myogenic dysfunction worsens stroke outcomes after acute hyperglycemic stroke in an oxidative stress-dependent manner. Male wild-type or SOD1 transgenic rats were injected with saline or 40% glucose solution 10 min before surgery and then subjected to 30 min of ischemia/45 min or 24 h of reperfusion. In another set of animals (n = 5), SOD1 was overexpressed only in the contralateral hemisphere by stereotaxic adenovirus injection 2-3 wk before I/R. Myogenic tone and neurovascular outcomes were determined. HG exacerbated myogenic dysfunction in contralateral side only, which was associated with infarct size expansion, increased edema, and more pronounced neurological deficit. Global and selective SOD1 overexpression restored myogenic reactivity in ipsilateral and contralateral sides, respectively, and enhanced neurovascular outcomes. In conclusion, our results show that SOD1 overexpression nullified the detrimental effects of HG on myogenic tone and stroke outcomes and that the contralateral hemisphere may be a novel target for the management of acute hyperglycemic stroke.
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Affiliation(s)
- Maha Coucha
- Department of Physiology, Georgia Regents University, Augusta, Georgia
| | - Weiguo Li
- Charlie Norwood Veterans Affairs Medical Center, Augusta, Georgia; Department of Physiology, Georgia Regents University, Augusta, Georgia
| | - Sherif Hafez
- Charlie Norwood Veterans Affairs Medical Center, Augusta, Georgia; Program in Clinical and Experimental Therapeutics, University of Georgia College of Pharmacy, Augusta, Georgia
| | - Mohammed Abdelsaid
- Charlie Norwood Veterans Affairs Medical Center, Augusta, Georgia; Department of Physiology, Georgia Regents University, Augusta, Georgia
| | - Maribeth H Johnson
- Department of Biostatistics, Georgia Regents University, Augusta, Georgia
| | - Susan C Fagan
- Charlie Norwood Veterans Affairs Medical Center, Augusta, Georgia; Department of Neurology, Georgia Regents University, Augusta, Georgia; and Program in Clinical and Experimental Therapeutics, University of Georgia College of Pharmacy, Augusta, Georgia
| | - Adviye Ergul
- Charlie Norwood Veterans Affairs Medical Center, Augusta, Georgia; Department of Physiology, Georgia Regents University, Augusta, Georgia; Program in Clinical and Experimental Therapeutics, University of Georgia College of Pharmacy, Augusta, Georgia
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Corbett D, Nguemeni C, Gomez-Smith M. How can you mend a broken brain? Neurorestorative approaches to stroke recovery. Cerebrovasc Dis 2014; 38:233-9. [PMID: 25402763 DOI: 10.1159/000368887] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2014] [Accepted: 10/06/2014] [Indexed: 11/19/2022] Open
Abstract
BACKGROUND Stroke is a devastating disorder that strikes approximately 15 million people worldwide. While most patients survive stroke, many are left with lifelong impairments, thereby making stroke the leading cause of permanent neurological disability. Despite this, there are a few options for treatment of acute stroke. Restoration of blood flow using clot-dissolving drugs has produced impressive benefits in some patients. However, for these drugs to be effective, they must be given soon after stroke onset and relatively only a few stroke patients reach hospital within this time. Side effects of these compounds further limit their use. SUMMARY Enhancing the brain's endogenous capacity for reorganization and self-repair offers the most promise for victims of stroke. Indeed, many stroke patients show considerable spontaneous functional improvement. Findings in the last 15 years suggest that stroke and related injury create a cerebral milieu similar to that of early brain development, a period characterized by rapid neuronal growth and neuroplasticity. A variety of interventions (e.g., stem cells, delivery of growth factors) are currently being explored in order to enhance neuroplasticity and reorganizational processes that are important for recovery of function. An emerging concept is that combinational or 'cocktail' therapies are more effective than single interventions in improving stroke recovery. Among these, one of the most promising therapies is enriched rehabilitation, a combination of environmental enrichment and task-specific therapy (e.g., reach training). KEY MESSAGES Neurorestorative approaches to brain reorganization and repair are providing new insights into how neural circuits respond to injury and how this knowledge can be used for optimizing stroke rehabilitation practice.
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Affiliation(s)
- Dale Corbett
- Department of Cellular & Molecular Medicine, Faculty of Medicine, University of Ottawa, Ottawa, Ont., Canada
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Faraji J, Soltanpour N, Moeeini R, Roudaki S, Soltanpour N, Abdollahi AA, Metz GAS. Topographical disorientation after ischemic mini infarct in the dorsal hippocampus: whispers in silence. Front Behav Neurosci 2014; 8:261. [PMID: 25136299 PMCID: PMC4120695 DOI: 10.3389/fnbeh.2014.00261] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2014] [Accepted: 07/14/2014] [Indexed: 11/17/2022] Open
Abstract
Silent focal ischemic mini infarcts in the brain are thought to cause no clinically overt symptoms. Some populations of hippocampal cells are particularly sensitive to ischemic events, however, rendering hippocampal functions especially vulnerable to ischemia-induced deficits. The present study investigated whether an otherwise silent ischemic mini infarct in the hippocampus (HPC) can produce impairments in spatial performance in rats. Spatial performance was assessed in the ziggurat task (ZT) using a 10-trial spatial learning protocol for 4 days prior to undergoing hippocampal ischemic lesion or sham surgery. Hippocampal silent ischemia was induced by infusion of endothelin-1 (ET-1), a potent vasoconstrictor, into either the dorsal or the ventral hippocampus (dHPC and vHPC). When tested postoperatively in the ZT using a standard testing protocol for 8 days, rats with hippocampal lesions exhibited no spatial deficit. Although spatial learning and memory in the ZT were not affected by the ET-1-induced silent ischemia, rats with dHPC stroke showed more returns when navigating the ZT as opposed to the vHPC rats. Comparison of region-specific HPC lesions in the present study indicated that dorsal hippocampal function is critically required for topographic orientation in a complex environment. Topographic disorientation as reflected by enhanced return behaviors may represent one of the earliest predictors of cognitive decline after silent ischemic insult that may be potentially traced with sensitive clinical examination in humans.
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Affiliation(s)
- Jamshid Faraji
- Department of Neuroscience, Canadian Centre for Behavioural Neuroscience (CCBN), University of Lethbridge Lethbridge, AB, Canada ; Faculty of Nursing and Midwifery, Golestan University of Medical Sciences Gorgan, Iran
| | - Nabiollah Soltanpour
- Department of Anatomy, Biology and Molecular Research Center, Babol University of Medical Sciences Babol, Iran
| | - Reza Moeeini
- Department of Behavioural Studies, Avicenna Institute of Neuroscience Yazd, Iran
| | - Shabnam Roudaki
- Department of Behavioural Studies, Avicenna Institute of Neuroscience Yazd, Iran
| | - Nasrin Soltanpour
- Department of Neuroscience, Canadian Centre for Behavioural Neuroscience (CCBN), University of Lethbridge Lethbridge, AB, Canada
| | - Ali-Akbar Abdollahi
- Faculty of Nursing and Midwifery, Golestan University of Medical Sciences Gorgan, Iran
| | - Gerlinde A S Metz
- Department of Neuroscience, Canadian Centre for Behavioural Neuroscience (CCBN), University of Lethbridge Lethbridge, AB, Canada
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Allred RP, Kim SY, Jones TA. Use it and/or lose it-experience effects on brain remodeling across time after stroke. Front Hum Neurosci 2014; 8:379. [PMID: 25018715 PMCID: PMC4072969 DOI: 10.3389/fnhum.2014.00379] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2013] [Accepted: 05/14/2014] [Indexed: 01/29/2023] Open
Abstract
The process of brain remodeling after stroke is time- and neural activity-dependent, and the latter makes it inherently sensitive to behavioral experiences. This generally supports targeting early dynamic periods of post-stroke neural remodeling with rehabilitative training (RT). However, the specific neural events that optimize RT effects are unclear and, as such, cannot be precisely targeted. Here we review evidence for, potential mechanisms of, and ongoing knowledge gaps surrounding time-sensitivities in RT efficacy, with a focus on findings from animal models of upper extremity RT. The reorganization of neural connectivity after stroke is a complex multiphasic process interacting with glial and vascular changes. Behavioral manipulations can impact numerous elements of this process to affect function. RT efficacy varies both with onset time and its timing relative to the development of compensatory strategies with the less-affected (nonparetic) hand. Earlier RT may not only capitalize on a dynamic period of brain remodeling but also counter a tendency for compensatory strategies to stamp-in suboptimal reorganization patterns. However, there is considerable variability across injuries and individuals in brain remodeling responses, and some early behavioral manipulations worsen function. The optimal timing of RT may remain unpredictable without clarification of the cellular events underlying time-sensitivities in its effects.
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Affiliation(s)
- Rachel P Allred
- Department of Psychology and Institute for Neuroscience, University of Texas at Austin Austin, TX, USA
| | - Soo Young Kim
- Department of Integrative Biology, University of California Berkeley Berkeley, CA, USA
| | - Theresa A Jones
- Department of Psychology and Institute for Neuroscience, University of Texas at Austin Austin, TX, USA
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Circulating miRNA profiles provide a biomarker for severity of stroke outcomes associated with age and sex in a rat model. Clin Sci (Lond) 2014; 127:77-89. [PMID: 24428837 DOI: 10.1042/cs20130565] [Citation(s) in RCA: 74] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
Small non-coding RNA [miRNA (microRNA)] found in the circulation have been used successfully as biomarkers and mechanistic targets for chronic and acute disease. The present study investigated the impact of age and sex on miRNA expression following ischaemic stroke in an animal model. Adult (6 month) and middle-aged (11-12 months) female and male rats were subject to MCAo (middle cerebral artery occlusion) using ET-1 (endothelin-1). Circulating miRNAs were analysed in blood samples at 2 and 5 days post-stroke, and brain miRNAs were analysed at 5 days post-stroke. Although stroke-associated infarction was observed in all groups, infarct volume and sensory-motor deficits were significantly reduced in adult females compared with middle-aged females, adult males or middle-aged males. At 2 days post-stroke, 21 circulating miRNAs were differentially regulated and PCA (principal component analysis) confirmed that most of the variance was due to age. At 5 days post-stroke, 78 circulating miRNAs exhibited significantly different regulation, and most of the variance was associated with sex. A small cohort (five) of miRNAs, miR-15a, miR-19b, miR-32 miR-136 and miR-199a-3p, were found to be highly expressed exclusively in adult females compared with middle-aged females, adult males and middle-aged males. Predicted gene targets for these five miRNAs analysed for KEGG (Kyoto Encyclopedia of Genes and Genomes) pathways revealed that the top ten KEGG pathways were related to growth factor signalling, cell structure and PI3K (phosphoinositide 3-kinase)/Akt and mTOR (mammalian target of rapamycin) signalling. Overall, the pattern of circulating miRNA expression suggests an early influence of age in stroke pathology, with a later emergence of sex as a factor for stroke severity.
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46
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Moldthan HL, Hirko AC, Thinschmidt JS, Grant MB, Li Z, Peris J, Lu Y, Elshikha AS, King MA, Hughes JA, Song S. Alpha 1-antitrypsin therapy mitigated ischemic stroke damage in rats. J Stroke Cerebrovasc Dis 2014; 23:e355-63. [PMID: 24582784 DOI: 10.1016/j.jstrokecerebrovasdis.2013.12.029] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2013] [Revised: 11/01/2013] [Accepted: 12/17/2013] [Indexed: 02/07/2023] Open
Abstract
Our objective is to develop a new therapy for the treatment of stroke. Currently, the only effective therapy for acute ischemic stroke is the thrombolytic agent recombinant tissue plasminogen activator. α1-Antitrypsin (AAT), a serine proteinase inhibitor with potent anti-inflammatory, anti-apoptotic, antimicrobial, and cytoprotective activities, could be beneficial in stroke. The goal of this study is to test whether AAT can improve ischemic stroke outcome in an established rat model. Middle cerebral artery occlusion was induced in male rats via intracranial (i.c.) microinjection of endothelin-1. Five to 10 minutes after stroke induction, rats received either i.c. or intravenous delivery of human AAT. Cylinder and vibrissae tests were used to evaluate sensorimotor function before and 72 hours after middle cerebral artery occlusion. Infarct volumes were examined via either 2,3,5-triphenyltetrazolium chloride assay or magnetic resonance imaging 72 hours after middle cerebral artery occlusion. Despite equivalent initial strokes, at 72 hours, the infarct volumes of the human AAT treatment groups (local and systemic injection) were statistically significantly reduced by 83% and 63% (P < .0001 and P < .05, respectively) compared with control rats. Human AAT significantly limited sensory motor system deficits. Human AAT could be a potential novel therapeutic drug for the protection against neurodegeneration after ischemic stroke, but more studies are needed to investigate the protective mechanisms and efficacy in other animal models.
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Affiliation(s)
- Huong L Moldthan
- Department of Pharmaceutics, University of Florida College of Pharmacy, Gainesville, Florida
| | - Aaron C Hirko
- Department of Pharmacology and Therapeutics, University of Florida College of Medicine, Gainesville, Florida
| | - Jeffrey S Thinschmidt
- Department of Pharmacology and Therapeutics, University of Florida College of Medicine, Gainesville, Florida
| | - Maria B Grant
- Department of Pharmacology and Therapeutics, University of Florida College of Medicine, Gainesville, Florida
| | - Zhimin Li
- Department of Pharmacodynamics, University of Florida College of Pharmacy, Gainesville, Florida
| | - Joanna Peris
- Department of Pharmacodynamics, University of Florida College of Pharmacy, Gainesville, Florida
| | - Yuanqing Lu
- Department of Pharmaceutics, University of Florida College of Pharmacy, Gainesville, Florida
| | - Ahmed S Elshikha
- Department of Pharmaceutics, University of Florida College of Pharmacy, Gainesville, Florida; Department of Pharmaceutics, Faculty of Pharmacy, Zagazig University, Zagazig, Sharkia, Egypt
| | - Michael A King
- Department of Pharmacology and Therapeutics, University of Florida College of Medicine, Gainesville, Florida; Department of Veterans Affairs Medical Center, Gainesville, Florida
| | | | - Sihong Song
- Department of Pharmaceutics, University of Florida College of Pharmacy, Gainesville, Florida.
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Teo L, Bourne JA. A reproducible and translatable model of focal ischemia in the visual cortex of infant and adult marmoset monkeys. Brain Pathol 2014; 24:459-74. [PMID: 25469561 DOI: 10.1111/bpa.12129] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2013] [Accepted: 01/21/2014] [Indexed: 12/12/2022] Open
Abstract
Models of ischemic brain injury in the nonhuman primate (NHP) are advantageous for investigating mechanisms of central nervous system (CNS) injuries and testing of new therapeutic strategies. However, issues of reproducibility and survivability persist in NHP models of CNS injuries. Furthermore, there are currently no pediatric NHP models of ischemic brain injury. Therefore, we have developed a NHP model of cortical focal ischemia that is highly reproducible throughout life to enable better understanding of downstream consequences of injury. Posterior cerebral arterial occlusion was induced through intracortical injections of endothelin-1 in adult (n = 5) and neonatal (n = 3) marmosets, followed by magnetic resonance imaging (MRI), histology and immunohistochemistry. MRI revealed tissue hyperintensity at the lesion site at 1-7 days followed by isointensity at 14-21 days. Peripheral macrophage and serum albumin infiltration was detected at 1 day, persisting at 21 days. The proportional loss of total V1 as a result of infarction was consistent in adults and neonates. Minor hemorrhagic transformation was detected at 21 days at the lesion core, while neovascularization was detected in neonates, but not in adults. We have developed a highly reproducible and survivable model of focal ischemia in the adult and neonatal marmoset primary visual cortex, demonstrating similar downstream anatomical and cellular pathology to those observed in post-ischemic humans.
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Affiliation(s)
- Leon Teo
- Australian Regenerative Medicine Institute, Monash University, Clayton, Vic., Australia
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Present status and future challenges of electroencephalography- and magnetic resonance imaging-based monitoring in preclinical models of focal cerebral ischemia. Brain Res Bull 2014; 102:22-36. [PMID: 24462642 DOI: 10.1016/j.brainresbull.2014.01.003] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2013] [Revised: 01/07/2014] [Accepted: 01/14/2014] [Indexed: 12/16/2022]
Abstract
Animal models are useful tools for better understanding the mechanisms underlying neurological deterioration after an ischemic insult as well as subsequent evolution of changes and recovery of functions. In response to the updated requirements for preclinical investigations of stroke to include relevant functional measurement techniques and biomarker endpoints, we here review the state of knowledge on application of some translational electrophysiological and neuroimaging methods, and in particular, electroencephalography monitoring and magnetic resonance imaging in rodent models of ischemic stroke. This may lead to improvement of diagnostic methods and identification of new therapeutic targets, which would considerably advance the translational value of preclinical stroke research.
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Tarulli E, Chaudhuri JD, Gretka V, Hoyles A, Morshead CM, Stanisz GJ. Effectiveness of micron-sized superparamagnetic iron oxide particles as markers for detection of migration of bone marrow-derived mesenchymal stromal cells in a stroke model. J Magn Reson Imaging 2014; 37:1409-18. [PMID: 23712844 DOI: 10.1002/jmri.23897] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2011] [Accepted: 09/18/2012] [Indexed: 01/30/2023] Open
Abstract
PURPOSE To evaluate the feasibility of using micron-sized superparamagnetic iron oxide particles (MPIOs) as an effective labeling agent for monitoring bone marrow-derived mesenchymal stromal cell (BMSC) migration in the brain using magnetic resonance imaging (MRI) in a rat model of stroke and whether the accumulation of MPIO-labeled BMSCs can be differentiated from the accumulation of free MPIO particles or hemoglobin breakdown at a site of neuronal damage. MATERIALS AND METHODS In this study BMSCs were labeled with iron oxide and their pattern of migration following intravenous injection in a rat stroke model was monitored using a clinical MRI system followed by standard histopathology. The migration pattern was compared between intravenous injection of BMSCs alone, BMSCs labeled with MPIOs, and MPIO particles alone. RESULTS The results demonstrated that while MRI was highly sensitive in the detection of iron oxide particle-containing cells in areas of neuronal ischemia, the true origin of cells containing iron oxide particles remains ambiguous. Therefore, detection of iron particles may not be a suitable strategy for the detection of BMSCs in the brain in a stroke model. CONCLUSION This study suggests that the use of MPIOs as labeling agents are insufficient to conclusively determine the localization of iron within cells in regions of neuronal ischemia and hemorrhage.
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Affiliation(s)
- Emidio Tarulli
- Department of Medical Biophysics, University of Toronto, Toronto, Ontario, Canada
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50
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Effects of skilled and unskilled training on functional recovery and brain plasticity after focal ischemia in adult rats. Brain Res 2012; 1486:53-61. [DOI: 10.1016/j.brainres.2012.09.019] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2012] [Revised: 09/08/2012] [Accepted: 09/11/2012] [Indexed: 11/23/2022]
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