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Wang P, Yang X, Yang F, Cardiff K, Houchins M, Carballo N, Shear DA, Scultetus AH, Bailey ZS. Intravenous Administration of Anti-CD47 Antibody Augments Hematoma Clearance, Mitigates Acute Neuropathology, and Improves Cognitive Function in a Rat Model of Penetrating Traumatic Brain Injury. J Neurotrauma 2024. [PMID: 38874230 DOI: 10.1089/neu.2024.0047] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/15/2024] Open
Abstract
Traumatic brain injury (TBI)-induced intracerebral hematoma is a major driver of secondary injury pathology such as neuroinflammation, cerebral edema, neurotoxicity, and blood-brain barrier dysfunction, which contribute to neuronal loss, motor deficits, and cognitive impairment. Cluster of differentiation 47 (CD47) is an antiphagocytic cell surface protein inhibiting hematoma clearance. This study was designed to evaluate the safety and efficacy of blockade of CD47 via intravenous (i.v.) administration of anti-CD47 antibodies following penetrating ballistic-like brain injury (PBBI) with significant traumatic intracerebral hemorrhage (tICH). The pharmacokinetic (PK) profile of the anti-CD47 antibody elicited that antibody concentration decayed over 7 days post-administration. Blood tests and necropsy analysis indicated no severe adverse events following treatment. Cerebral hemoglobin levels were significantly increased after injury, however, anti-CD47 antibody administration at 0.1 mg/kg resulted in a significant reduction in cerebral hemoglobin levels at 72 h post-administration, indicating augmentation of hematoma clearance. Immunohistochemistry assessment of glial fibrillary acidic protein (GFAP) and ionized calcium-binding adaptor molecule 1 (IBA1) demonstrated a significant reduction of GFAP levels in the lesion core and peri-lesional area. Based on these analyses, the optimal dose was identified as 0.1 mg/kg. Lesion volume showed a reduction following treatment. Rotarod testing revealed significant motor deficits in all injured groups but no significant therapeutic benefits. Spatial learning performance revealed significant deficits in all injured groups, which were significantly improved by the last testing day. Anti-CD47 antibody treated rats showed significantly improved attention deficits, but not retention scores. These results provide preliminary evidence that blockade of CD47 using i.v. administration of anti-CD47 antibodies may serve as a potential therapeutic for TBI with ICH.
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Affiliation(s)
- Ping Wang
- Brain Trauma Neuroprotection, Walter Reed Army Institute of Research, Silver Spring, Maryland, USA
| | - Xiaofang Yang
- Brain Trauma Neuroprotection, Walter Reed Army Institute of Research, Silver Spring, Maryland, USA
| | - Fangzhou Yang
- Brain Trauma Neuroprotection, Walter Reed Army Institute of Research, Silver Spring, Maryland, USA
| | - Katherine Cardiff
- Brain Trauma Neuroprotection, Walter Reed Army Institute of Research, Silver Spring, Maryland, USA
| | - Melonie Houchins
- Brain Trauma Neuroprotection, Walter Reed Army Institute of Research, Silver Spring, Maryland, USA
| | - Noemy Carballo
- Brain Trauma Neuroprotection, Walter Reed Army Institute of Research, Silver Spring, Maryland, USA
| | - Deborah A Shear
- Brain Trauma Neuroprotection, Walter Reed Army Institute of Research, Silver Spring, Maryland, USA
| | - Anke H Scultetus
- Brain Trauma Neuroprotection, Walter Reed Army Institute of Research, Silver Spring, Maryland, USA
| | - Zachary S Bailey
- Brain Trauma Neuroprotection, Walter Reed Army Institute of Research, Silver Spring, Maryland, USA
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2
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Scepanovic G, Fernandez-Gonzalez R. Should I shrink or should I grow: cell size changes in tissue morphogenesis. Genome 2024; 67:125-138. [PMID: 38198661 DOI: 10.1139/gen-2023-0091] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2024]
Abstract
Cells change shape, move, divide, and die to sculpt tissues. Common to all these cell behaviours are cell size changes, which have recently emerged as key contributors to tissue morphogenesis. Cells can change their mass-the number of macromolecules they contain-or their volume-the space they encompass. Changes in cell mass and volume occur through different molecular mechanisms and at different timescales, slow for changes in mass and rapid for changes in volume. Therefore, changes in cell mass and cell volume, which are often linked, contribute to the development and shaping of tissues in different ways. Here, we review the molecular mechanisms by which cells can control and alter their size, and we discuss how changes in cell mass and volume contribute to tissue morphogenesis. The role that cell size control plays in developing embryos is only starting to be elucidated. Research on the signals that control cell size will illuminate our understanding of the cellular and molecular mechanisms that drive tissue morphogenesis.
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Affiliation(s)
- Gordana Scepanovic
- Department of Cell and Systems Biology, University of Toronto, Toronto, ON M5S 3G5, Canada
- Ted Rogers Centre for Heart Research, University of Toronto, Toronto, ON M5G 1M1, Canada
- Institute of Biomedical Engineering, University of Toronto, Toronto, ON M5S 3G9, Canada
| | - Rodrigo Fernandez-Gonzalez
- Department of Cell and Systems Biology, University of Toronto, Toronto, ON M5S 3G5, Canada
- Ted Rogers Centre for Heart Research, University of Toronto, Toronto, ON M5G 1M1, Canada
- Institute of Biomedical Engineering, University of Toronto, Toronto, ON M5S 3G9, Canada
- Developmental and Stem Cell Biology Program, The Hospital for Sick Children, Toronto, ON, M5G 1X8, Canada
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3
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Tang S, Xu S, Wilder D, Medina AE, Li X, Fiskum GM, Jiang L, Kakulavarapu VR, Long JB, Gullapalli RP, Sajja VS. Longitudinal Biochemical and Behavioral Alterations in a Gyrencephalic Model of Blast-Related Mild Traumatic Brain Injury. Neurotrauma Rep 2024; 5:254-266. [PMID: 38515547 PMCID: PMC10956534 DOI: 10.1089/neur.2024.0002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/23/2024] Open
Abstract
Blast-related traumatic brain injury (bTBI) is a major cause of neurological disorders in the U.S. military that can adversely impact some civilian populations as well and can lead to lifelong deficits and diminished quality of life. Among these types of injuries, the long-term sequelae are poorly understood because of variability in intensity and number of the blast exposure, as well as the range of subsequent symptoms that can overlap with those resulting from other traumatic events (e.g., post-traumatic stress disorder). Despite the valuable insights that rodent models have provided, there is a growing interest in using injury models using species with neuroanatomical features that more closely resemble the human brain. With this purpose, we established a gyrencephalic model of blast injury in ferrets, which underwent blast exposure applying conditions that closely mimic those associated with primary blast injuries to warfighters. In this study, we evaluated brain biochemical, microstructural, and behavioral profiles after blast exposure using in vivo longitudinal magnetic resonance imaging, histology, and behavioral assessments. In ferrets subjected to blast, the following alterations were found: 1) heightened impulsivity in decision making associated with pre-frontal cortex/amygdalar axis dysfunction; 2) transiently increased glutamate levels that are consistent with earlier findings during subacute stages post-TBI and may be involved in concomitant behavioral deficits; 3) abnormally high brain N-acetylaspartate levels that potentially reveal disrupted lipid synthesis and/or energy metabolism; and 4) dysfunction of pre-frontal cortex/auditory cortex signaling cascades that may reflect similar perturbations underlying secondary psychiatric disorders observed in warfighters after blast exposure.
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Affiliation(s)
- Shiyu Tang
- Department of Diagnostic Radiology and Nuclear Medicine, Trauma, and Anesthesiology Research Center, University of Maryland School of Medicine, Baltimore, Maryland, USA
- Center for Advanced Imaging Research (CAIR), Trauma, and Anesthesiology Research Center, University of Maryland School of Medicine, Baltimore, Maryland, USA
| | - Su Xu
- Department of Diagnostic Radiology and Nuclear Medicine, Trauma, and Anesthesiology Research Center, University of Maryland School of Medicine, Baltimore, Maryland, USA
- Center for Advanced Imaging Research (CAIR), Trauma, and Anesthesiology Research Center, University of Maryland School of Medicine, Baltimore, Maryland, USA
| | - Donna Wilder
- Blast Induced Neurotrauma Branch, Walter Reed Army Institute of Research, Silver Spring, Maryland, USA
| | - Alexandre E. Medina
- Department of Pediatrics, Trauma, and Anesthesiology Research Center, University of Maryland School of Medicine, Baltimore, Maryland, USA
| | - Xin Li
- Department of Diagnostic Radiology and Nuclear Medicine, Trauma, and Anesthesiology Research Center, University of Maryland School of Medicine, Baltimore, Maryland, USA
- Center for Advanced Imaging Research (CAIR), Trauma, and Anesthesiology Research Center, University of Maryland School of Medicine, Baltimore, Maryland, USA
| | - Gary M. Fiskum
- Department of Anesthesiology, Trauma, and Anesthesiology Research Center, University of Maryland School of Medicine, Baltimore, Maryland, USA
- Shock, Trauma, and Anesthesiology Research Center, University of Maryland School of Medicine, Baltimore, Maryland, USA
| | - Li Jiang
- Department of Diagnostic Radiology and Nuclear Medicine, Trauma, and Anesthesiology Research Center, University of Maryland School of Medicine, Baltimore, Maryland, USA
- Center for Advanced Imaging Research (CAIR), Trauma, and Anesthesiology Research Center, University of Maryland School of Medicine, Baltimore, Maryland, USA
| | - Venkata R. Kakulavarapu
- Blast Induced Neurotrauma Branch, Walter Reed Army Institute of Research, Silver Spring, Maryland, USA
| | - Joseph B. Long
- Blast Induced Neurotrauma Branch, Walter Reed Army Institute of Research, Silver Spring, Maryland, USA
| | - Rao P. Gullapalli
- Department of Diagnostic Radiology and Nuclear Medicine, Trauma, and Anesthesiology Research Center, University of Maryland School of Medicine, Baltimore, Maryland, USA
- Center for Advanced Imaging Research (CAIR), Trauma, and Anesthesiology Research Center, University of Maryland School of Medicine, Baltimore, Maryland, USA
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Elder GA, Gama Sosa MA, De Gasperi R, Perez Garcia G, Perez GM, Abutarboush R, Kawoos U, Zhu CW, Janssen WGM, Stone JR, Hof PR, Cook DG, Ahlers ST. The Neurovascular Unit as a Locus of Injury in Low-Level Blast-Induced Neurotrauma. Int J Mol Sci 2024; 25:1150. [PMID: 38256223 PMCID: PMC10816929 DOI: 10.3390/ijms25021150] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2023] [Revised: 01/11/2024] [Accepted: 01/11/2024] [Indexed: 01/24/2024] Open
Abstract
Blast-induced neurotrauma has received much attention over the past decade. Vascular injury occurs early following blast exposure. Indeed, in animal models that approximate human mild traumatic brain injury or subclinical blast exposure, vascular pathology can occur in the presence of a normal neuropil, suggesting that the vasculature is particularly vulnerable. Brain endothelial cells and their supporting glial and neuronal elements constitute a neurovascular unit (NVU). Blast injury disrupts gliovascular and neurovascular connections in addition to damaging endothelial cells, basal laminae, smooth muscle cells, and pericytes as well as causing extracellular matrix reorganization. Perivascular pathology becomes associated with phospho-tau accumulation and chronic perivascular inflammation. Disruption of the NVU should impact activity-dependent regulation of cerebral blood flow, blood-brain barrier permeability, and glymphatic flow. Here, we review work in an animal model of low-level blast injury that we have been studying for over a decade. We review work supporting the NVU as a locus of low-level blast injury. We integrate our findings with those from other laboratories studying similar models that collectively suggest that damage to astrocytes and other perivascular cells as well as chronic immune activation play a role in the persistent neurobehavioral changes that follow blast injury.
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Affiliation(s)
- Gregory A. Elder
- Neurology Service, James J. Peters Department of Veterans Affairs Medical Center, 130 West Kingsbridge Road, Bronx, NY 10468, USA
- Department of Neurology, Icahn School of Medicine at Mount Sinai, One Gustave Levy Place, New York, NY 10029, USA;
- Department of Psychiatry, Icahn School of Medicine at Mount Sinai, One Gustave Levy Place, New York, NY 10029, USA; (M.A.G.S.); (R.D.G.)
- Mount Sinai Alzheimer’s Disease Research Center and the Ronald M. Loeb Center for Alzheimer’s Disease, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA; (C.W.Z.); (P.R.H.)
| | - Miguel A. Gama Sosa
- Department of Psychiatry, Icahn School of Medicine at Mount Sinai, One Gustave Levy Place, New York, NY 10029, USA; (M.A.G.S.); (R.D.G.)
- General Medical Research Service, James J. Peters Department of Veterans Affairs Medical Center, Bronx, NY 10468, USA
| | - Rita De Gasperi
- Department of Psychiatry, Icahn School of Medicine at Mount Sinai, One Gustave Levy Place, New York, NY 10029, USA; (M.A.G.S.); (R.D.G.)
- Research and Development Service, James J. Peters Department of Veterans Affairs Medical Center, 130 West Kingsbridge Road, Bronx, NY 10468, USA;
| | - Georgina Perez Garcia
- Department of Neurology, Icahn School of Medicine at Mount Sinai, One Gustave Levy Place, New York, NY 10029, USA;
- Research and Development Service, James J. Peters Department of Veterans Affairs Medical Center, 130 West Kingsbridge Road, Bronx, NY 10468, USA;
| | - Gissel M. Perez
- Research and Development Service, James J. Peters Department of Veterans Affairs Medical Center, 130 West Kingsbridge Road, Bronx, NY 10468, USA;
| | - Rania Abutarboush
- Department of Neurotrauma, Operational and Undersea Medicine Directorate, Naval Medical ResearchCommand, 503 Robert Grant Avenue, Silver Spring, MD 20910, USA; (R.A.); (U.K.); (S.T.A.)
- The Henry M. Jackson Foundation for the Advancement of Military Medicine Inc., Bethesda, MD 20817, USA
| | - Usmah Kawoos
- Department of Neurotrauma, Operational and Undersea Medicine Directorate, Naval Medical ResearchCommand, 503 Robert Grant Avenue, Silver Spring, MD 20910, USA; (R.A.); (U.K.); (S.T.A.)
- The Henry M. Jackson Foundation for the Advancement of Military Medicine Inc., Bethesda, MD 20817, USA
| | - Carolyn W. Zhu
- Mount Sinai Alzheimer’s Disease Research Center and the Ronald M. Loeb Center for Alzheimer’s Disease, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA; (C.W.Z.); (P.R.H.)
- Research and Development Service, James J. Peters Department of Veterans Affairs Medical Center, 130 West Kingsbridge Road, Bronx, NY 10468, USA;
- Department of Geriatrics and Palliative Care, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA
| | - William G. M. Janssen
- Nash Family Department of Neuroscience, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA;
- Friedman Brain Institute, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA
| | - James R. Stone
- Department of Radiology and Medical Imaging, University of Virginia, 480 Ray C Hunt Drive, Charlottesville, VA 22903, USA;
| | - Patrick R. Hof
- Mount Sinai Alzheimer’s Disease Research Center and the Ronald M. Loeb Center for Alzheimer’s Disease, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA; (C.W.Z.); (P.R.H.)
- Department of Geriatrics and Palliative Care, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA
- Nash Family Department of Neuroscience, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA;
- Friedman Brain Institute, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA
| | - David G. Cook
- Geriatric Research Education and Clinical Center, VA Puget Sound Health Care System, 1660 S Columbian Way, Seattle, WA 98108, USA;
- Department of Medicine, University of Washington, 1959 NE Pacific St., Seattle, WA 98195, USA
| | - Stephen T. Ahlers
- Department of Neurotrauma, Operational and Undersea Medicine Directorate, Naval Medical ResearchCommand, 503 Robert Grant Avenue, Silver Spring, MD 20910, USA; (R.A.); (U.K.); (S.T.A.)
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Heyburn L, Dahal S, Abutarboush R, Reed E, Urioste R, Batuure A, Wilder D, Ahlers ST, Long JB, Sajja VS. Differential effects on TDP-43, piezo-2, tight-junction proteins in various brain regions following repetitive low-intensity blast overpressure. Front Neurol 2023; 14:1237647. [PMID: 37877029 PMCID: PMC10593467 DOI: 10.3389/fneur.2023.1237647] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2023] [Accepted: 09/15/2023] [Indexed: 10/26/2023] Open
Abstract
Introduction Mild traumatic brain injury (mTBI) caused by repetitive low-intensity blast overpressure (relBOP) in military personnel exposed to breaching and heavy weapons is often unrecognized and is understudied. Exposure to relBOP poses the risk of developing abnormal behavioral and psychological changes such as altered cognitive function, anxiety, and depression, all of which can severely compromise the quality of the life of the affected individual. Due to the structural and anatomical heterogeneity of the brain, understanding the potentially varied effects of relBOP in different regions of the brain could lend insights into the risks from exposures. Methods In this study, using a rodent model of relBOP and western blotting for protein expression we showed the differential expression of various neuropathological proteins like TDP-43, tight junction proteins (claudin-5, occludin, and glial fibrillary acidic protein (GFAP)) and a mechanosensitive protein (piezo-2) in different regions of the brain at different intensities and frequency of blast. Results Our key results include (i) significant increase in claudin-5 after 1x blast of 6.5 psi in all three regions and no definitive pattern with higher number of blasts, (ii) significant increase in piezo-2 at 1x followed by significant decrease after multiple blasts in the cortex, (iii) significant increase in piezo-2 with increasing number of blasts in frontal cortex and mixed pattern of expression in hippocampus and (iv) mixed pattern of TDP-3 and GFAP expression in all the regions of brain. Discussion These results suggest that there are not definitive patterns of changes in these marker proteins with increase in intensity and/or frequency of blast exposure in any particular region; the changes in expression of these proteins are different among the regions. We also found that the orientation of blast exposure (e.g. front vs. side exposure) affects the altered expression of these proteins.
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Affiliation(s)
- Lanier Heyburn
- Blast Induced Neurotrauma Branch, Walter Reed Army Institute of Research, Silver Spring, MD, United States
| | - Shataakshi Dahal
- Blast Induced Neurotrauma Branch, Walter Reed Army Institute of Research, Silver Spring, MD, United States
- The Geneva Foundation, Tacoma, WA, United States
| | | | - Eileen Reed
- Naval Medical Research Center, Silver Spring, MD, United States
| | - Rodrigo Urioste
- Blast Induced Neurotrauma Branch, Walter Reed Army Institute of Research, Silver Spring, MD, United States
| | - Andrew Batuure
- Blast Induced Neurotrauma Branch, Walter Reed Army Institute of Research, Silver Spring, MD, United States
| | - Donna Wilder
- Blast Induced Neurotrauma Branch, Walter Reed Army Institute of Research, Silver Spring, MD, United States
| | | | - Joseph B. Long
- Blast Induced Neurotrauma Branch, Walter Reed Army Institute of Research, Silver Spring, MD, United States
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Walilko TJ, Sewsankar K, Wagner CD, Podolski A, Smith K, Zai L, Bentley TB. The Application of Machine Learning to Identify Large Animal Blast Exposure Thresholds. Mil Med 2023; 188:e600-e606. [PMID: 34677603 DOI: 10.1093/milmed/usab410] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2021] [Revised: 04/16/2021] [Accepted: 09/27/2021] [Indexed: 11/13/2022] Open
Abstract
INTRODUCTION The Office of Naval Research sponsored the Blast Load Assessment Sense and Test program to develop a rapid, in-field solution that could be used by team leaders, commanders, and medical personnel to make science-based stand-down decisions for service members exposed to blast overpressure. Toward this goal, the authors propose an ensemble approach based on machine learning (ML) methods to derive a threshold surface for potential neurological deficits that encompasses the intensity of the blast events, the number of exposures, and the period over which the exposures occurred. Because of collection challenges presented by human subjects, the authors utilized data representing a comprehensive set of measures, including structural, behavioral, and cellular changes, from preclinical large animal studies on minipig models. This article describes the development process used to procure the resulting methodology from these studies. METHODS AND MATERIALS Using an ensemble of ML methods applied to experimental data obtained from 71 Yucatan minipigs, the relationship between blast exposure and neurological deficits was delineated. Despite a relatively small sample size, ML methods with k-fold cross-validation (with k = 5) were justified because of the complexity of the dataset reflecting numerous nonlinear relationships between cellular, structural, and behavioral markers. Based on the physiological responses and environmental measures collected during the large animal study, two models were developed to investigate the relationship between multiple outcome measures and exposure to blast. The histological features model was trained on single-exposure animal data to predict a binary injury response (injured or not) using histological features. The environmental features model related the observed behavioral changes to the environmental parameters collected. RESULTS The histological features model predicted a binary injury outcome from cellular and physiological measurements. Features identified in developing this classification model showed some level of correlation to observed behavioral changes, suggesting that glial activation inflammation and neurodegenerative responses occur even at the lowest levels of blast exposures tested. The results of the environmental features model, which estimated injury risk from environmental blast exposure characteristics, suggested that the observed changes are not just a function of impulse but an average dynamic impulse rate. Noticeable behavioral deficits were observed at loading rates of 100 kPa (impulse/positive duration) or peak pressures of 300-350 kPa, with an approximate positive phase duration of 3.4 ms for single exposure. Based on this analysis, a 3D threshold surface was developed to characterize the potential risk of neurological deficits. CONCLUSIONS The ensemble approach facilitated the identification of a pattern of changes across multiple variables to predict the occurrence of changes in brain function. Many changes observed after blast exposure were subtle, making them difficult to measure in human subjects. ML methodologies applied to minipig data demonstrated the value of these techniques in analyzing complex datasets to complement human studies. Importantly, the threshold surface supports the development of science-based blast exposure guidelines.
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Affiliation(s)
| | - Kiran Sewsankar
- Applied Research Associates, Inc., Albuquerque, NM 87110, USA
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The Imbalance of Astrocytic Mitochondrial Dynamics Following Blast-Induced Traumatic Brain Injury. Biomedicines 2023; 11:biomedicines11020329. [PMID: 36830865 PMCID: PMC9953570 DOI: 10.3390/biomedicines11020329] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2022] [Revised: 01/13/2023] [Accepted: 01/17/2023] [Indexed: 01/27/2023] Open
Abstract
Mild blast-induced traumatic brain injury (bTBI) is a modality of injury that has been of major concern considering a large number of military personnel exposed to explosive blast waves. bTBI results from the propagation of high-pressure static blast forces and their subsequent energy transmission within brain tissue. Exposure to this overpressure energy causes a diffuse injury that leads to acute cell damage and, if chronic, leads to detrimental long-term cognitive deficits. The literature presents a neuro-centric approach to the role of mitochondria dynamics dysfunction in bTBI, and changes in astrocyte-specific mitochondrial dynamics have not been characterized. The balance between fission and fusion events is known as mitochondrial dynamics. As a result of fission and fusion, the mitochondrial structure is constantly altering its shape to respond to physiological stimuli or stress, which in turn affects mitochondrial function. Astrocytic mitochondria are recognized to play an essential role in overall brain metabolism, synaptic transmission, and neuron protection. Mitochondria are vulnerable to injury insults, leading to the increase in mitochondrial fission, a mechanism controlled by the GTPase dynamin-related protein (Drp1) and the phosphorylation of Drp1 at serine 616 (p-Drp1s616). This site is critical to mediate the Drp1 translocation to mitochondria to promote fission events and consequently leads to fragmentation. An increase in mitochondrial fragmentation could have negative consequences, such as promoting an excessive generation of reactive oxygen species or triggering cytochrome c release. The aim of the present study was to characterize the unique pattern of astrocytic mitochondrial dynamics by exploring the role of DRP1 with a combination of in vitro and in vivo bTBI models. Differential remodeling of the astrocytic mitochondrial network was observed, corresponding with increases in p-Drp1S616 four hours and seven days post-injury. Further, results showed a time-dependent reactive astrocyte phenotype transition in the rat hippocampus. This discovery can lead to innovative therapeutics targets to help prevent the secondary injury cascade after blast injury that involves mitochondria dysfunction.
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Dickerson MR, Murphy SF, Urban MJ, White Z, VandeVord PJ. Chronic Anxiety- and Depression-Like Behaviors Are Associated With Glial-Driven Pathology Following Repeated Blast Induced Neurotrauma. Front Behav Neurosci 2021; 15:787475. [PMID: 34955781 PMCID: PMC8703020 DOI: 10.3389/fnbeh.2021.787475] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2021] [Accepted: 11/19/2021] [Indexed: 12/27/2022] Open
Abstract
Long-term neuropsychiatric impairments have become a growing concern following blast-related traumatic brain injury (bTBI) in active military personnel and Veterans. Neuropsychiatric impairments such as anxiety and depression are common comorbidities that Veterans report months, even years following injury. To understand these chronic behavioral outcomes following blast injury, there is a need to study the link between anxiety, depression, and neuropathology. The hippocampus and motor cortex (MC) have been regions of interest when studying cognitive deficits following blast exposure, but clinical studies of mood disorders such as major depressive disorder (MDD) report that these two regions also play a role in the manifestation of anxiety and depression. With anxiety and depression being common long-term outcomes following bTBI, it is imperative to study how chronic pathological changes within the hippocampus and/or MC due to blast contribute to the development of these psychiatric impairments. In this study, we exposed male rats to a repeated blast overpressure (~17 psi) and evaluated the chronic behavioral and pathological effects on the hippocampus and MC. Results demonstrated that the repeated blast exposure led to depression-like behaviors 36 weeks following injury, and anxiety-like behaviors 2-, and 52-weeks following injury. These behaviors were also correlated with astrocyte pathology (glial-fibrillary acid protein, GFAP) and dendritic alterations (Microtubule-Associated Proteins, MAP2) within the hippocampus and MC regions at 52 weeks. Overall, these findings support the premise that chronic glial pathological changes within the brain contribute to neuropsychiatric impairments following blast exposure.
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Affiliation(s)
- Michelle R. Dickerson
- Department of Biomedical Engineering and Mechanics, Virginia Tech, Blacksburg, VA, United States
| | - Susan F. Murphy
- Department of Biomedical Engineering and Mechanics, Virginia Tech, Blacksburg, VA, United States
| | - Michael J. Urban
- Department of Biomedical Engineering and Mechanics, Virginia Tech, Blacksburg, VA, United States
| | - Zakar White
- Department of Biomedical Engineering and Mechanics, Virginia Tech, Blacksburg, VA, United States
| | - Pamela J. VandeVord
- Department of Biomedical Engineering and Mechanics, Virginia Tech, Blacksburg, VA, United States
- Salem VA Medical Center, Salem, VA, United States
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9
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Anderson MB, Das S, Miller KE. Subcellular localization of neuronal nuclei (NeuN) antigen in size and calcitonin gene-related peptide (CGRP) populations of dorsal root ganglion (DRG) neurons during acute peripheral inflammation. Neurosci Lett 2021; 760:135974. [PMID: 34146639 DOI: 10.1016/j.neulet.2021.135974] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2020] [Revised: 05/14/2021] [Accepted: 05/17/2021] [Indexed: 10/21/2022]
Abstract
Pseudo-unipolar cell bodies of somatosensory primary neurons are located in the dorsal root ganglia (DRG). The somatic and peripheral domains of DRG neurons are often studied in sensory pain research to understand molecular mechanisms involved in the activation of pain and maintenance of inflammation. Adjuvant-induced arthritis (AIA) is an inflammatory model that elicits a robust and rapid onset immune response with a maximal swelling period of 24-48 h and persisting for several weeks. The AIA model in the hind paw of the rat elicits a potent inflammatory response of the dermis and epidermis, leading to protein expression changes for sensitization of many DRG neurons; however, it is unknown if the AIA model in the hind paw of the rat induces DRG neuronal injury, necrosis, or apoptosis at the somatic level. Neuronal nuclei (NeuN) antigen is a biomarker for post-mitotic neurons, neuronal identification, protein alterations, injury, and loss. Calcitonin gene-related peptide (CGRP) is expressed in C and Aδ DRG neurons, a subset of DRG neurons known to play a role in peripheral sensitization. The focus of this research was to evaluate the expression pattern of NeuN immunoreactivity, in size (soma) and CGRP subpopulations of DRG neurons in naïve and inflamed groups. Confirmed by both immunofluorescence and immunoprecipitation, DRG neuronal expression of NeuN was localized to nuclear and cytoplasmic subcellular compartments. NeuN increased within the nucleus of small CGRP positive DRG neurons during inflammation, indicating a potential role for NeuN in a subset of nociceptive neurons.
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Affiliation(s)
- Michael B Anderson
- Oklahoma State University Center for Health Sciences, Anatomy & Cell Biology (E-453/461), 1111 W 17th St, Tulsa OK, 74135, United States(1).
| | - Subhas Das
- Oklahoma State University Center for Health Sciences, Anatomy & Cell Biology (E-453/461), 1111 W 17th St, Tulsa OK, 74135, United States(1)
| | - Kenneth E Miller
- Oklahoma State University Center for Health Sciences, Anatomy & Cell Biology (E-453/461), 1111 W 17th St, Tulsa OK, 74135, United States(1)
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10
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McCabe JT, Tucker LB. Sex as a Biological Variable in Preclinical Modeling of Blast-Related Traumatic Brain Injury. Front Neurol 2020; 11:541050. [PMID: 33101170 PMCID: PMC7554632 DOI: 10.3389/fneur.2020.541050] [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: 03/06/2020] [Accepted: 08/14/2020] [Indexed: 12/14/2022] Open
Abstract
Approaches to furthering our understanding of the bioeffects, behavioral changes, and treatment options following exposure to blast are a worldwide priority. Of particular need is a more concerted effort to employ animal models to determine possible sex differences, which have been reported in the clinical literature. In this review, clinical and preclinical reports concerning blast injury effects are summarized in relation to sex as a biological variable (SABV). The review outlines approaches that explore the pertinent role of sex chromosomes and gonadal steroids for delineating sex as a biological independent variable. Next, underlying biological factors that need exploration for blast effects in light of SABV are outlined, including pituitary, autonomic, vascular, and inflammation factors that all have evidence as having important SABV relevance. A major second consideration for the study of SABV and preclinical blast effects is the notable lack of consistent model design—a wide range of devices have been employed with questionable relevance to real-life scenarios—as well as poor standardization for reporting of blast parameters. Hence, the review also provides current views regarding optimal design of shock tubes for approaching the problem of primary blast effects and sex differences and outlines a plan for the regularization of reporting. Standardization and clear description of blast parameters will provide greater comparability across models, as well as unify consensus for important sex difference bioeffects.
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Affiliation(s)
- Joseph T McCabe
- Pre-clinical Studies Core, Center for Neuroscience and Regenerative Medicine, Bethesda, IL, United States.,Department of Anatomy, Physiology & Genetics, F.E. Hébert School of Medicine, Uniformed Services University of the Health Sciences, Bethesda, MD, United States
| | - Laura B Tucker
- Pre-clinical Studies Core, Center for Neuroscience and Regenerative Medicine, Bethesda, IL, United States.,Department of Anatomy, Physiology & Genetics, F.E. Hébert School of Medicine, Uniformed Services University of the Health Sciences, Bethesda, MD, United States
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11
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Hlavac N, Guilhaume-Corrêa F, VandeVord PJ. Mechano-stimulation initiated by extracellular adhesion and cationic conductance pathways influence astrocyte activation. Neurosci Lett 2020; 739:135405. [PMID: 32979460 DOI: 10.1016/j.neulet.2020.135405] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2020] [Revised: 09/10/2020] [Accepted: 09/21/2020] [Indexed: 11/13/2022]
Abstract
Traumatic brain injury (TBI) represents a major cause of long-term disability worldwide. Primary damage to brain tissue leads to complex secondary injury mechanisms involving inflammation, oxidative stress and cellular activation/reactivity. The molecular pathways that exacerbate brain cell dysfunction after injury are not well understood and provide challenges to developing TBI therapeutics. This study aimed to delineate mechanisms of astrocyte activation induced by mechano-stimulation, specifically involving extracellular adhesion and cationic transduction. An in vitro model was employed to investigate 2D and 3D cultures of primary astrocytes, in which cells were exposed to a single high-rate overpressure known to cause upregulation of structural and proliferative markers within 72 h of exposure. An inhibitor of focal adhesion kinase (FAK) phosphorylation, TAE226, was used to demonstrate a relationship between extracellular adhesion perturbations and structural reactivity in the novel 3D model. TAE226 mitigated upregulation of glial fibrillary acidic protein in 3D cultures by 72 h post-exposure. Alternatively, incubation with gadolinium (a cationic channel blocker) during overpressure, demonstrated a role for cationic transduction in reducing the increased levels of proliferating cell nuclear antigen that occur at 24 h post-stimulation. Furthermore, early changes in mitochondrial polarization at 15 min and in endogenous ATP levels at 4-6 h occur post-overpressure and may be linked to later changes in cell phenotype. By 24 h, there was evidence of increased amine metabolism and increased nicotinamide adenine dinucleotide phosphate oxidase (NOX4) production. The overproduction of NOX4 was counteracted by gadolinium during overpressure exposure. Altogether, the results of this study indicated that both extracellular adhesion (via FAK activation) and cationic conductance (via ion channels) contribute to early patterns of astrocyte activation following overpressure stimulation. Mechano-stimulation pathways are linked to bioenergetic and metabolic disruptions in astrocytes that influence downstream oxidative stress, aberrant proliferative capacity and structural reactivity.
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Affiliation(s)
- Nora Hlavac
- Virginia Tech, Department of Biomedical Engineering and Mechanics, Blacksburg, VA, USA
| | | | - Pamela J VandeVord
- Virginia Tech, Department of Biomedical Engineering and Mechanics, Blacksburg, VA, USA; Salem Veterans Affairs Medical Center, Department of Research, Salem, VA, USA.
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12
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Heyburn L, Abutarboush R, Goodrich S, Urioste R, Batuure A, Statz J, Wilder D, Ahlers ST, Long JB, Sajja VSSS. Repeated Low-Level Blast Overpressure Leads to Endovascular Disruption and Alterations in TDP-43 and Piezo2 in a Rat Model of Blast TBI. Front Neurol 2019; 10:766. [PMID: 31417481 PMCID: PMC6682625 DOI: 10.3389/fneur.2019.00766] [Citation(s) in RCA: 39] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2019] [Accepted: 07/01/2019] [Indexed: 11/29/2022] Open
Abstract
Recent evidence linking repeated low-level blast overpressure exposure in operational and training environments with neurocognitive decline, neuroinflammation, and neurodegenerative processes has prompted concern over the cumulative deleterious effects of repeated blast exposure on the brains of service members. Repetitive exposure to low-level primary blast may cause symptoms (subclinical) similar to those seen in mild traumatic brain injury (TBI), with progressive vascular and cellular changes, which could contribute to neurodegeneration. At the cellular level, the mechanical force associated with blast exposure can cause cellular perturbations in the brain, leading to secondary injury. To examine the cumulative effects of repetitive blast on the brain, an advanced blast simulator (ABS) was used to closely mimic “free-field” blast. Rats were exposed to 1–4 daily blasts (one blast per day, separated by 24 h) at 13, 16, or 19 psi peak incident pressures with a positive duration of 4–5 ms, either in a transverse or longitudinal orientation. Blood-brain barrier (BBB) markers (vascular endothelial growth factor (VEGF), occludin, and claudin-5), transactive response DNA binding protein (TDP-43), and the mechanosensitive channel Piezo2 were measured following blast exposure. Changes in expression of VEGF, occludin, and claudin-5 after repeated blast exposure indicate alterations in the BBB, which has been shown to be disrupted following TBI. TDP-43 is very tightly regulated in the brain and altered expression of TDP-43 is found in clinically-diagnosed TBI patients. TDP-43 levels were differentially affected by the number and magnitude of blast exposures, decreasing after 2 exposures, but increasing following a greater number of exposures at various intensities. Lastly, Piezo2 has been shown to be dysregulated following blast exposure and was here observed to increase after multiple blasts of moderate magnitude, indicating that blast may cause a change in sensitivity to mechanical stimuli in the brain and may contribute to cellular injury. These findings reveal that cumulative effects of repeated exposures to blast can lead to pathophysiological changes in the brain, demonstrating a possible link between blast injury and neurodegenerative disease, which is an important first step in understanding how to prevent these diseases in soldiers exposed to blast.
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Affiliation(s)
- Lanier Heyburn
- Walter Reed Army Institute of Research, Blast Induced Neurotrauma Branch, Silver Spring, MD, United States
| | - Rania Abutarboush
- Neurotrauma Department, Naval Medical Research Center, Silver Spring, MD, United States.,Henry M. Jackson Foundation for the Advancement of Military Medicine, Inc., Bethesda, MD, United States
| | - Samantha Goodrich
- Neurotrauma Department, Naval Medical Research Center, Silver Spring, MD, United States.,Henry M. Jackson Foundation for the Advancement of Military Medicine, Inc., Bethesda, MD, United States
| | - Rodrigo Urioste
- Walter Reed Army Institute of Research, Blast Induced Neurotrauma Branch, Silver Spring, MD, United States
| | - Andrew Batuure
- Walter Reed Army Institute of Research, Blast Induced Neurotrauma Branch, Silver Spring, MD, United States
| | - Jonathan Statz
- Neurotrauma Department, Naval Medical Research Center, Silver Spring, MD, United States.,Henry M. Jackson Foundation for the Advancement of Military Medicine, Inc., Bethesda, MD, United States
| | - Donna Wilder
- Walter Reed Army Institute of Research, Blast Induced Neurotrauma Branch, Silver Spring, MD, United States
| | - Stephen T Ahlers
- Neurotrauma Department, Naval Medical Research Center, Silver Spring, MD, United States
| | - Joseph B Long
- Walter Reed Army Institute of Research, Blast Induced Neurotrauma Branch, Silver Spring, MD, United States
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13
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Glotfelty EJ, Delgado TE, Tovar-y-Romo LB, Luo Y, Hoffer BJ, Olson L, Karlsson TE, Mattson MP, Harvey BK, Tweedie D, Li Y, Greig NH. Incretin Mimetics as Rational Candidates for the Treatment of Traumatic Brain Injury. ACS Pharmacol Transl Sci 2019; 2:66-91. [PMID: 31396586 PMCID: PMC6687335 DOI: 10.1021/acsptsci.9b00003] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2019] [Indexed: 12/17/2022]
Abstract
Traumatic brain injury (TBI) is becoming an increasing public health issue. With an annually estimated 1.7 million TBIs in the United States (U.S) and nearly 70 million worldwide, the injury, isolated or compounded with others, is a major cause of short- and long-term disability and mortality. This, along with no specific treatment, has made exploration of TBI therapies a priority of the health system. Age and sex differences create a spectrum of vulnerability to TBI, with highest prevalence among younger and older populations. Increased public interest in the long-term effects and prevention of TBI have recently reached peaks, with media attention bringing heightened awareness to sport and war related head injuries. Along with short-term issues, TBI can increase the likelihood for development of long-term neurodegenerative disorders. A growing body of literature supports the use of glucagon-like peptide-1 (GLP-1), glucose-dependent insulinotropic peptide (GIP), and glucagon (Gcg) receptor (R) agonists, along with unimolecular combinations of these therapies, for their potent neurotrophic/neuroprotective activities across a variety of cellular and animal models of chronic neurodegenerative diseases (Alzheimer's and Parkinson's diseases) and acute cerebrovascular disorders (stroke). Mild or moderate TBI shares many of the hallmarks of these conditions; recent work provides evidence that use of these compounds is an effective strategy for its treatment. Safety and efficacy of many incretin-based therapies (GLP-1 and GIP) have been demonstrated in humans for the treatment of type 2 diabetes mellitus (T2DM), making these compounds ideal for rapid evaluation in clinical trials of mild and moderate TBI.
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Affiliation(s)
- Elliot J. Glotfelty
- Translational
Gerontology Branch, and Laboratory of Neurosciences, Intramural
Research Program, National Institute on
Aging, National Institutes of Health, Baltimore, Maryland 21224, United States
- Department
of Neuroscience, Karolinska Institutet, Stockholm, Sweden
| | - Thomas E. Delgado
- Translational
Gerontology Branch, and Laboratory of Neurosciences, Intramural
Research Program, National Institute on
Aging, National Institutes of Health, Baltimore, Maryland 21224, United States
| | - Luis B. Tovar-y-Romo
- Division
of Neuroscience, Institute of Cellular Physiology, Universidad Nacional Autónoma de México, Mexico City, Mexico
| | - Yu Luo
- Department
of Molecular Genetics, University of Cincinnati, Cincinnati, Ohio 45221, United States
| | - Barry J. Hoffer
- Department
of Neurosurgery, Case Western Reserve University
School of Medicine, Cleveland, Ohio 44106, United States
| | - Lars Olson
- Department
of Neuroscience, Karolinska Institutet, Stockholm, Sweden
| | | | - Mark P. Mattson
- Translational
Gerontology Branch, and Laboratory of Neurosciences, Intramural
Research Program, National Institute on
Aging, National Institutes of Health, Baltimore, Maryland 21224, United States
| | - Brandon K. Harvey
- Molecular
Mechanisms of Cellular Stress and Inflammation Unit, Integrative Neuroscience
Department, National Institute on Drug Abuse,
National Institutes of Health, Baltimore, Maryland 21224, United States
| | - David Tweedie
- Translational
Gerontology Branch, and Laboratory of Neurosciences, Intramural
Research Program, National Institute on
Aging, National Institutes of Health, Baltimore, Maryland 21224, United States
| | - Yazhou Li
- Translational
Gerontology Branch, and Laboratory of Neurosciences, Intramural
Research Program, National Institute on
Aging, National Institutes of Health, Baltimore, Maryland 21224, United States
| | - Nigel H. Greig
- Translational
Gerontology Branch, and Laboratory of Neurosciences, Intramural
Research Program, National Institute on
Aging, National Institutes of Health, Baltimore, Maryland 21224, United States
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14
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Hlavac N, VandeVord PJ. Astrocyte Mechano-Activation by High-Rate Overpressure Involves Alterations in Structural and Junctional Proteins. Front Neurol 2019; 10:99. [PMID: 30853931 PMCID: PMC6395392 DOI: 10.3389/fneur.2019.00099] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2018] [Accepted: 01/24/2019] [Indexed: 11/13/2022] Open
Abstract
Primary blast neurotrauma represents a unique injury paradigm characterized by high-rate overpressure effects on brain tissue. One major hallmark of blast neurotrauma is glial reactivity, notably prolonged astrocyte activation. This cellular response has been mainly defined in primary blast neurotrauma by increased intermediate filament expression. Because the intermediate filament networks physically interface with transmembrane proteins for junctional support, it was hypothesized that cell junction regulation is altered in the reactive phenotype as well. This would have implications for downstream transcriptional regulation via signal transduction pathways like nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB). Therefore, a custom high-rate overpressure simulator was built for in vitro testing using mechanical conditions based on intracranial pressure measurements in a rat model of blast neurotrauma. Primary rat astrocytes were exposed to isolated high-rate mechanical stimulation to study cell junction dynamics in relation to their mechano-activation. First, a time course for "classical" features of reactivity was devised by evaluation of glial fibrillary acidic protein (GFAP) and proliferating cell nuclear antigen (PCNA) expression. This was followed by gene and protein expression for both gap junction (connexins) and anchoring junction proteins (integrins and cadherins). Signal transduction analysis was carried out by nuclear localization of two molecules, NF-κB p65 and mitogen-activated protein kinase (MAPK) p38. Results indicated significant increases in connexin-43 expression and PCNA first at 24 h post-overpressure (p < 0.05), followed by structural reactivity (via increased GFAP, p < 0.05) corresponding to increased anchoring junction dynamics at 48 h post-overpressure (p < 0.05). Moreover, increased phosphorylation of focal adhesion kinase (FAK) was observed in addition to increased nuclear localization of both p65 and p38 (p < 0.05) during the period of structural reactivity. To evaluate the transcriptional activity of p65 in the nucleus, electrophoretic mobility shift assay was conducted for a binding site on the promoter region for intracellular adhesion molecule-1 (ICAM-1), an antagonist of tight junctions. A significant increase in the interaction of nuclear proteins with the NF-κB site on the ICAM-1 corresponded to increased gene and protein expression of ICAM-1 (p < 0.05). Altogether, these results indicate multiple targets and corresponding signaling pathways which involve cell junction dynamics in the mechano-activation of astrocytes following high-rate overpressure.
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Affiliation(s)
- Nora Hlavac
- Department of Biomedical Engineering and Mechanics, Virginia Polytechnic Institute, Blacksburg, VA, United States
| | - Pamela J VandeVord
- Department of Biomedical Engineering and Mechanics, Virginia Polytechnic Institute, Blacksburg, VA, United States.,Department of Research, Salem Veterans Affairs Medical Center, Salem, VA, United States
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15
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β-Alanine supplementation reduces anxiety and increases neurotrophin expression in both young and older rats. Nutr Res 2019; 62:51-63. [DOI: 10.1016/j.nutres.2018.11.001] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2018] [Revised: 10/28/2018] [Accepted: 11/01/2018] [Indexed: 12/29/2022]
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16
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Gepner Y, Hoffman JR, Hoffman MW, Zelicha H, Cohen H, Ostfeld I. Association between circulating inflammatory markers and marksmanship following intense military training. J ROY ARMY MED CORPS 2018; 165:391-394. [DOI: 10.1136/jramc-2018-001084] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2018] [Revised: 11/15/2018] [Accepted: 11/18/2018] [Indexed: 01/05/2023]
Abstract
IntroductionIntense military operations during deployment or training are associated with elevations in inflammatory cytokine markers. However, the influence of an inflammatory response on military-specific skills is unclear. This study examined the association between brain-derived neurotrophic factor (BDNF), glial fibrillar acidic protein, markers of inflammation, marksmanship and cognitive function following a week of intense military field training.MethodsTwenty male soldiers (20.1±0.6 years; 1.78±0.05m; 74.1±7.9kg) from the same elite combat unit of the Israel Defense Forces volunteered to participate in this study. Soldiers completed a five-day period of intense field training including navigation of 27.8km/day with load carriages of ~50% of their body mass. Soldiers slept approximately fivehours per day and were provided with military field rations. Following the final navigational exercise, soldiers returned to their base and provided a blood sample. In addition, cognitive function assessment and both dynamic and static shooting (15 shots each) were performed following a 200 m gauntlet, in which soldiers had to use hand-to-hand combat skills to reach the shooting range.ResultsResults revealed that tumour necrosis factor-α (TNF-α) concentrations were inversely correlated with dynamic shooting (r=−0.646, p=0.005). In addition, a trend (r=0.415, p=0.098) was noted between TNF-α concentrations and target engagement speed (ie, time to complete the shooting protocol). BDNF concentrations were significantly correlated with the Serial Sevens Test performance (r=0.672, p=0.012).ConclusionThe results of this investigation indicate that elevated TNF-α concentrations and lower BDNF concentrations in soldiers following intense military training were associated with decreases in marksmanship and cognitive function, respectively.
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17
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Esenaliev RO, Petrov IY, Petrov Y, Guptarak J, Boone DR, Mocciaro E, Weisz H, Parsley MA, Sell SL, Hellmich H, Ford JM, Pogue C, DeWitt D, Prough DS, Micci MA. Nano-Pulsed Laser Therapy Is Neuroprotective in a Rat Model of Blast-Induced Neurotrauma. J Neurotrauma 2018; 35:1510-1522. [PMID: 29562823 PMCID: PMC5998828 DOI: 10.1089/neu.2017.5249] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
Abstract
We have developed a novel, non-invasive nano-pulsed laser therapy (NPLT) system that combines the benefits of near-infrared laser light (808 nm) and ultrasound (optoacoustic) waves, which are generated with each short laser pulse within the tissue. We tested NPLT in a rat model of blast-induced neurotrauma (BINT) to determine whether transcranial application of NPLT provides neuroprotective effects. The laser pulses were applied on the intact rat head 1 h after injury using a specially developed fiber-optic system. Vestibulomotor function was assessed on post-injury days (PIDs) 1–3 on the beam balance and beam walking tasks. Cognitive function was assessed on PIDs 6–10 using a working memory Morris water maze (MWM) test. BDNF and caspase-3 messenger RNA (mRNA) expression was measured by quantitative real-time PCR (qRT-PCR) in laser-captured cortical neurons. Microglia activation and neuronal injury were assessed in brain sections by immunofluorescence using specific antibodies against CD68 and active caspase-3, respectively. In the vestibulomotor and cognitive (MWM) tests, NPLT-treated animals performed significantly better than the untreated blast group and similarly to sham animals. NPLT upregulated mRNA encoding BDNF and downregulated the pro-apoptotic protein caspase-3 in cortical neurons. Immunofluorescence demonstrated that NPLT inhibited microglia activation and reduced the number of cortical neurons expressing activated caspase-3. NPLT also increased expression of BDNF in the hippocampus and the number of proliferating progenitor cells in the dentate gyrus. Our data demonstrate a neuroprotective effect of NPLT and prompt further studies aimed to develop NPLT as a therapeutic intervention after traumatic brain injury (TBI).
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Affiliation(s)
- Rinat O Esenaliev
- 1 Department of Anesthesiology, University of Texas Medical Branch , Galveston, Texas.,2 Department of Neuroscience and Cell Biology, University of Texas Medical Branch , Galveston, Texas.,3 Center for Biomedical Engineering, University of Texas Medical Branch , Galveston, Texas
| | - Irene Y Petrov
- 3 Center for Biomedical Engineering, University of Texas Medical Branch , Galveston, Texas
| | - Yuriy Petrov
- 3 Center for Biomedical Engineering, University of Texas Medical Branch , Galveston, Texas
| | - Jutatip Guptarak
- 1 Department of Anesthesiology, University of Texas Medical Branch , Galveston, Texas
| | - Debbie R Boone
- 1 Department of Anesthesiology, University of Texas Medical Branch , Galveston, Texas
| | - Emanuele Mocciaro
- 1 Department of Anesthesiology, University of Texas Medical Branch , Galveston, Texas
| | - Harris Weisz
- 1 Department of Anesthesiology, University of Texas Medical Branch , Galveston, Texas
| | - Margaret A Parsley
- 1 Department of Anesthesiology, University of Texas Medical Branch , Galveston, Texas
| | - Stacy L Sell
- 1 Department of Anesthesiology, University of Texas Medical Branch , Galveston, Texas
| | - Helen Hellmich
- 1 Department of Anesthesiology, University of Texas Medical Branch , Galveston, Texas
| | - Jonathan M Ford
- 1 Department of Anesthesiology, University of Texas Medical Branch , Galveston, Texas
| | - Connor Pogue
- 1 Department of Anesthesiology, University of Texas Medical Branch , Galveston, Texas
| | - Douglas DeWitt
- 1 Department of Anesthesiology, University of Texas Medical Branch , Galveston, Texas
| | - Donald S Prough
- 1 Department of Anesthesiology, University of Texas Medical Branch , Galveston, Texas
| | - Maria-Adelaide Micci
- 1 Department of Anesthesiology, University of Texas Medical Branch , Galveston, Texas
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18
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Fievisohn E, Bailey Z, Guettler A, VandeVord P. Primary Blast Brain Injury Mechanisms: Current Knowledge, Limitations, and Future Directions. J Biomech Eng 2018; 140:2666247. [DOI: 10.1115/1.4038710] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2017] [Indexed: 12/18/2022]
Abstract
Mild blast traumatic brain injury (bTBI) accounts for the majority of brain injury in United States service members and other military personnel worldwide. The mechanisms of primary blast brain injury continue to be disputed with little evidence to support one or a combination of theories. The main hypotheses addressed in this review are blast wave transmission through the skull orifices, direct cranial transmission, skull flexure dynamics, thoracic surge, acceleration, and cavitation. Each possible mechanism is discussed using available literature with the goal of focusing research efforts to address the limitations and challenges that exist in blast injury research. Multiple mechanisms may contribute to the pathology of bTBI and could be dependent on magnitudes and orientation to blast exposure. Further focused biomechanical investigation with cadaver, in vivo, and finite element models would advance our knowledge of bTBI mechanisms. In addition, this understanding could guide future research and contribute to the greater goal of developing relevant injury criteria and mandates to protect our soldiers on the battlefield.
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Affiliation(s)
- Elizabeth Fievisohn
- Department of Biomedical Engineering and Mechanics, Virginia Tech, 440 Kelly Hall, 325 Stanger Street, Blacksburg, VA 24061 e-mail:
| | - Zachary Bailey
- Department of Biomedical Engineering and Mechanics, Virginia Tech, 440 Kelly Hall, 325 Stanger Street, Blacksburg, VA 24061 e-mail:
| | - Allison Guettler
- Department of Mechanical Engineering, Virginia Tech, 440 Kelly Hall, 325 Stanger Street, Blacksburg, VA 24061 e-mail:
| | - Pamela VandeVord
- Department of Biomedical Engineering and Mechanics, Virginia Tech, 317 Kelly Hall, 325 Stanger Street, Blacksburg, VA 24061; Salem Veterans Affairs Medical Center, Salam, VA 24153 e-mail:
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19
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DeWalt GJ, Mahajan B, Foster AR, Thompson LDE, Marttini AA, Schmidt EV, Mansuri S, D'Souza D, Patel SB, Tenenbaum M, Brandao-Viruet KI, Thompson D, Duong B, Smith DH, Blute TA, Eldred WD. Region-specific alterations in astrocyte and microglia morphology following exposure to blasts in the mouse hippocampus. Neurosci Lett 2017; 664:160-166. [PMID: 29133177 DOI: 10.1016/j.neulet.2017.11.016] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2017] [Revised: 11/07/2017] [Accepted: 11/07/2017] [Indexed: 12/28/2022]
Abstract
Traumatic brain injury (TBI) is a serious public health concern, especially injuries from repetitive insults. The main objective of this study was to immunocytochemically examine morphological alterations in astrocytes and microglia in the hippocampus 48h following a single blast versus multiple blasts in adult C57BL/6 mice. The effects of ketamine and xylazine (KX), two common anesthetic agents used in TBI research, were also evaluated due to the confounding effect of anesthetics on injury outcome. Results showed a significant increase in hypertrophic microglia that was limited to the outer molecular layer of the dentate gyrus, but only in the absence of KX. Although the presence or absence of KX had no effect on astrocytes following a single blast, a significant decrease in astrocytic immunoreactivity was observed in the stratum lacunosum moleculare following multiple blasts in the absence of KX. The morphological changes in astrocytes and microglia reported in this study reveal region-specific differences in the absence of KX that could have significant implications for our interpretation of glial alterations in animal models of injury.
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Affiliation(s)
| | | | | | | | | | | | - Sara Mansuri
- Boston University, Department of Biology, United States
| | | | - Shama B Patel
- Boston University, Department of Biology, United States
| | | | | | | | - Bryan Duong
- Boston University, Department of Biology, United States
| | | | - Todd A Blute
- Boston University, Department of Biology, United States
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20
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Chen H, Desai A, Kim HY. Repetitive Closed-Head Impact Model of Engineered Rotational Acceleration Induces Long-Term Cognitive Impairments with Persistent Astrogliosis and Microgliosis in Mice. J Neurotrauma 2017; 34:2291-2302. [PMID: 28288551 DOI: 10.1089/neu.2016.4870] [Citation(s) in RCA: 37] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
Repeated mild traumatic brain injury (rmTBI) has been identified by epidemiology as a high-risk factor for dementia at a later stage in life. Animal models to replicate complex features of human rmTBI and/or to evaluate long-term effects on brain function have not been established. In this study, we used a novel closed-head impact model of engineered rotational acceleration (CHIMERA) to investigate the long-term neuropathological and cognitive functional consequences of rmTBI. Adult C57BL/6 male mice were subjected to CHIMERA for 3 consecutive days 24 h apart. Functional outcomes were assessed by the beam walk and Morris water maze tests. Neuropathology was evaluated by immunostaining of glial fibrillary acidic protein (GFAP), amyloid precursor protein (APP), and ionizing calcium-binding adaptor molecule-1 (Iba-1), and by quantitative reverse transcription polymerase chain reaction (qRT-PCR) or Western blotting of GFAP, Iba-1, and tumor necrosis factor (TNF)-α. Repeated CHIMERA (rCHIMERA) resulted in motor deficits at 3 days, and in learning and memory impairments that were sustained up to 6 months post injury. GFAP and TNF-α gene expression was increased within a week, whereas astrogliosis and microgliosis were induced starting from day 1 up to 6.5 months after rCHIMERA with upregulated GFAP and Iba-1 protein levels. rCHIMERA also induced APP deposition from day 1 to day 7, but this diminished by 1 month. In conclusion, rCHIMERA produces long-lasting cognitive impairments with astrogliosis and microgliosis in mice, suggesting that rCHIMERA can be a useful animal model to study the long-term complications, as well as the cellular and molecular mechanisms, of human rmTBI.
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Affiliation(s)
- Huazhen Chen
- 1 Laboratory of Molecular Signaling, National Institute on Alcohol Abuse and Alcoholism, National Institutes of Health , Rockville, Maryland.,2 Center for Neuroscience and Regenerative Medicine at the Uniformed Services University of Health Sciences , Bethesda, Maryland
| | - Abhishek Desai
- 1 Laboratory of Molecular Signaling, National Institute on Alcohol Abuse and Alcoholism, National Institutes of Health , Rockville, Maryland
| | - Hee-Yong Kim
- 1 Laboratory of Molecular Signaling, National Institute on Alcohol Abuse and Alcoholism, National Institutes of Health , Rockville, Maryland
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21
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Behavioral and inflammatory response in animals exposed to a low-pressure blast wave and supplemented with β-alanine. Amino Acids 2017; 49:871-886. [PMID: 28161798 PMCID: PMC5383715 DOI: 10.1007/s00726-017-2383-8] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2016] [Accepted: 01/18/2017] [Indexed: 12/30/2022]
Abstract
This study investigated the benefit of β-alanine (BA) supplementation on behavioral and cognitive responses relating to mild traumatic brain injury (mTBI) and post-traumatic stress disorder (PTSD) in rats exposed to a low-pressure blast wave. Animals were fed a normal diet with or without (PL) BA supplementation (100 mg kg−1) for 30-day, prior to being exposed to a low-pressure blast wave. A third group of animals served as a control (CTL). These animals were fed a normal diet, but were not exposed to the blast. Validated cognitive-behavioral paradigms were used to assess both mTBI and PTSD-like behavior on days 7–14 following the blast. Brain-derived neurotrophic factor (BDNF), neuropeptide Y, glial fibrillary acidic protein (GFAP) and tau protein expressions were analyzed a day later. In addition, brain carnosine and histidine content was assessed as well. The prevalence of animals exhibiting mTBI-like behavior was significantly lower (p = 0.044) in BA than PL (26.5 and 46%, respectively), but no difference (p = 0.930) was noted in PTSD-like behavior between the groups (10.2 and 12.0%, respectively). Carnosine content in the cerebral cortex was higher (p = 0.048) for BA compared to PL, while a trend towards a difference was seen in the hippocampus (p = 0.058) and amygdala (p = 0.061). BDNF expression in the CA1 subregion of PL was lower than BA (p = 0.009) and CTL (p < 0.001), while GFAP expression in CA1 (p = 0.003) and CA3 (p = 0.040) subregions were higher in PL than other groups. Results indicated that BA supplementation for 30-day increased resiliency to mTBI in animals exposed to a low-pressure blast wave.
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Kallakuri S, Desai A, Feng K, Tummala S, Saif T, Chen C, Zhang L, Cavanaugh JM, King AI. Neuronal Injury and Glial Changes Are Hallmarks of Open Field Blast Exposure in Swine Frontal Lobe. PLoS One 2017; 12:e0169239. [PMID: 28107370 PMCID: PMC5249202 DOI: 10.1371/journal.pone.0169239] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2015] [Accepted: 12/13/2016] [Indexed: 02/03/2023] Open
Abstract
With the rapid increase in the number of blast induced traumatic brain injuries and associated neuropsychological consequences in veterans returning from the operations in Iraq and Afghanistan, the need to better understand the neuropathological sequelae following exposure to an open field blast exposure is still critical. Although a large body of experimental studies have attempted to address these pathological changes using shock tube models of blast injury, studies directed at understanding changes in a gyrencephalic brain exposed to a true open field blast are limited and thus forms the focus of this study. Anesthetized, male Yucatan swine were subjected to forward facing medium blast overpressure (peak side on overpressure 224-332 kPa; n = 7) or high blast overpressure (peak side on overpressure 350-403 kPa; n = 5) by detonating 3.6 kg of composition-4 charge. Sham animals (n = 5) were subjected to all the conditions without blast exposure. After a 3-day survival period, the brain was harvested and sections from the frontal lobes were processed for histological assessment of neuronal injury and glial reactivity changes. Significant neuronal injury in the form of beta amyloid precursor protein immunoreactive zones in the gray and white matter was observed in the frontal lobe sections from both the blast exposure groups. A significant increase in the number of astrocytes and microglia was also observed in the blast exposed sections compared to sham sections. We postulate that the observed acute injury changes may progress to chronic periods after blast and may contribute to short and long-term neuronal degeneration and glial mediated inflammation.
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Affiliation(s)
- Srinivasu Kallakuri
- Department of Biomedical Engineering, Wayne State University, Detroit, Michigan, United States of America
| | - Alok Desai
- Department of Biomedical Engineering, Wayne State University, Detroit, Michigan, United States of America
| | - Ke Feng
- Department of Biomedical Engineering, Wayne State University, Detroit, Michigan, United States of America
| | - Sharvani Tummala
- Department of Biomedical Engineering, Wayne State University, Detroit, Michigan, United States of America
| | - Tal Saif
- Department of Biomedical Engineering, Wayne State University, Detroit, Michigan, United States of America
| | - Chaoyang Chen
- Department of Biomedical Engineering, Wayne State University, Detroit, Michigan, United States of America
| | - Liying Zhang
- Department of Biomedical Engineering, Wayne State University, Detroit, Michigan, United States of America
| | - John M. Cavanaugh
- Department of Biomedical Engineering, Wayne State University, Detroit, Michigan, United States of America
| | - Albert I. King
- Department of Biomedical Engineering, Wayne State University, Detroit, Michigan, United States of America
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Bailey ZS, Grinter MB, VandeVord PJ. Astrocyte Reactivity Following Blast Exposure Involves Aberrant Histone Acetylation. Front Mol Neurosci 2016; 9:64. [PMID: 27551260 PMCID: PMC4976110 DOI: 10.3389/fnmol.2016.00064] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2016] [Accepted: 07/21/2016] [Indexed: 12/17/2022] Open
Abstract
Blast induced neurotrauma (BINT) is a prevalent injury within military and civilian populations. The injury is characterized by persistent inflammation at the cellular level which manifests as a multitude of cognitive and functional impairments. Epigenetic regulation of transcription offers an important control mechanism for gene expression and cellular function which may underlie chronic inflammation and result in neurodegeneration. We hypothesize that altered histone acetylation patterns may be involved in blast induced inflammation and the chronic activation of glial cells. This study aimed to elucidate changes to histone acetylation occurring following injury and the roles these changes may have within the pathology. Sprague Dawley rats were subjected to either a 10 or 17 psi blast overpressure within an Advanced Blast Simulator (ABS). Sham animals underwent the same procedures without blast exposure. Memory impairments were measured using the Novel Object Recognition (NOR) test at 2 and 7 days post-injury. Tissues were collected at 7 days for Western blot and immunohistochemistry (IHC) analysis. Sham animals showed intact memory at each time point. The novel object discrimination decreased significantly between two and 7 days for each injury group (p < 0.05). This is indicative of the onset of memory impairment. Western blot analysis showed glial fibrillary acidic protein (GFAP), a known marker of activated astrocytes, was elevated in the prefrontal cortex (PFC) following blast exposure for both injury groups. Analysis of histone protein extract showed no changes in the level of any total histone proteins within the PFC. However, acetylation levels of histone H2b, H3, and H4 were decreased in both groups (p < 0.05). Co-localization immunofluorescence was used to further investigate any potential correlation between decreased histone acetylation and astrocyte activation. These experiments showed a similar decrease in H3 acetylation in astrocytes exposed to a 17 psi blast but not a 10 psi blast. Further investigation of gene expression by polymerase chain reaction (PCR) array, showed dysregulation of several cytokine and cytokine receptors that are involved in neuroinflammatory processes. We have shown aberrant histone acetylation patterns involved in blast induced astrogliosis and cognitive impairments. Further understanding of their role in the injury progression may lead to novel therapeutic targets.
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Affiliation(s)
- Zachary S Bailey
- Department of Biomedical Engineering and Mechanics, Virginia Tech Blacksburg, VA, USA
| | - Michael B Grinter
- Department of Biomedical Engineering and Mechanics, Virginia Tech Blacksburg, VA, USA
| | - Pamela J VandeVord
- Department of Biomedical Engineering and Mechanics, Virginia TechBlacksburg, VA, USA; Salem Veterans Affairs Medical CenterSalem, VA, USA
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Subacute Oxidative Stress and Glial Reactivity in the Amygdala are Associated with Increased Anxiety Following Blast Neurotrauma. Shock 2016; 44 Suppl 1:71-8. [PMID: 25521536 DOI: 10.1097/shk.0000000000000311] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
Behavioral symptoms, such as anxiety, are widely reported after blast overpressure (BOP) exposure. Amygdalar vulnerability to increasing magnitudes of BOP has not been investigated, and single exposures to blast have been limited to acute (<72 h) assessment. Rats were exposed to a single low, moderate, or high BOP (10, 14, or 24 psi) with an advanced blast simulator to test the susceptibility of the amygdala. Anxiety-like behavior was observed in the low- and moderate-pressure groups when subjected to the light/dark box assessment 7 days after the blast but not in high-pressure group. Immunohistochemistry was performed to measure apoptosis (cleaved caspase-3), neuronal loss (NeuN), reactive astrocytes (glial fibrillary acidic protein), microglia (Iba-1), and oxidative stress (CuZn superoxide dismutase). Slower progression of injury cascades was associated with a significant increase in anxiety, apoptosis, and astrogliosis in the low pressure group compared with others. A significant increase of CuZn superoxide dismutase in the low pressure group could be associated with neuroprotection from cell death caused by oxidative stress because neuronal loss was significant in the moderate- and high- but not the low-pressure group. Overall, this study demonstrated that overpressure as low as 10 psi can induce subacute anxiety, in addition to neuropathologic changes in the amygdala.
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Effgen GB, Ong T, Nammalwar S, Ortuño AI, Meaney DF, 'Dale' Bass CR, Morrison B. Primary Blast Exposure Increases Hippocampal Vulnerability to Subsequent Exposure: Reducing Long-Term Potentiation. J Neurotrauma 2016; 33:1901-1912. [PMID: 26699926 DOI: 10.1089/neu.2015.4327] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023] Open
Abstract
Up to 80% of injuries sustained by U.S. soldiers in Operation Enduring Freedom and Operation Iraqi Freedom were the result of blast exposure from improvised explosive devices. Some soldiers experience multiple blasts while on duty, and it has been suggested that symptoms of repetitive blast are similar to those that follow multiple non-blast concussions, such as sport-related concussion. Despite the interest in the effects of repetitive blast exposure, it remains unknown whether an initial blast renders the brain more vulnerable to subsequent exposure, resulting in a synergistic injury response. To investigate the effect of multiple primary blasts on the brain, organotypic hippocampal slice cultures were exposed to single or repetitive (two or three total) primary blasts of varying intensities. Long-term potentiation was significantly reduced following two Level 2 (92.7 kPa, 1.4 msec, 38.5 kPa·msec) blasts delivered 24 h apart without altering basal evoked response. This deficit persisted when the interval between injuries was increased to 72 h but not when the interval was extended to 144 h. The repeated blast exposure with a 24 h interval increased microglia staining and activation significantly but did not significantly increase cell death or damage axons, dendrites, or principal cell layers. Lack of overt structural damage and change in basal stimulated neuron response suggest that injury from repetitive primary blast exposure may specifically affect long-term potentiation. Our studies suggest repetitive primary blasts can exacerbate injury dependent on the injury severity and interval between exposures.
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Affiliation(s)
- Gwen B Effgen
- 1 Department of Biomedical Engineering, Columbia University , New York, New York
| | - Tiffany Ong
- 1 Department of Biomedical Engineering, Columbia University , New York, New York
| | - Shruthi Nammalwar
- 1 Department of Biomedical Engineering, Columbia University , New York, New York
| | - Andrea I Ortuño
- 1 Department of Biomedical Engineering, Columbia University , New York, New York
| | - David F Meaney
- 2 Department of Bioengineering, University of Pennsylvania , Philadelphia, Pennsylvania
| | | | - Barclay Morrison
- 1 Department of Biomedical Engineering, Columbia University , New York, New York
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Sajja VSSS, Hlavac N, VandeVord PJ. Role of Glia in Memory Deficits Following Traumatic Brain Injury: Biomarkers of Glia Dysfunction. Front Integr Neurosci 2016; 10:7. [PMID: 26973475 PMCID: PMC4770450 DOI: 10.3389/fnint.2016.00007] [Citation(s) in RCA: 75] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2015] [Accepted: 02/05/2016] [Indexed: 12/15/2022] Open
Abstract
Historically, glial cells have been recognized as a structural component of the brain. However, it has become clear that glial cells are intimately involved in the complexities of neural networks and memory formations. Astrocytes, microglia, and oligodendrocytes have dynamic responsibilities which substantially impact neuronal function and activities. Moreover, the importance of glia following brain injury has come to the forefront in discussions to improve axonal regeneration and functional recovery. The numerous activities of glia following injury can either promote recovery or underlie the pathobiology of memory deficits. This review outlines the pathological states of glial cells which evolve from their positive supporting roles to those which disrupt synaptic function and neuroplasticity following injury. Evidence suggests that glial cells interact extensively with neurons both chemically and physically, reinforcing their role as pivotal for higher brain functions such as learning and memory. Collectively, this mini review surveys investigations of how glial dysfunction following brain injury can alter mechanisms of synaptic plasticity and how this may be related to an increased risk for persistent memory deficits. We also include recent findings, that demonstrate new molecular avenues for clinical biomarker discovery.
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Affiliation(s)
- Venkata S S S Sajja
- Cellular Imaging Section and Vascular Biology Program, Department of Radiology and Radiological Science, Institute for Cell Engineering, Johns Hopkins University School of Medicine Baltimore, MA, USA
| | - Nora Hlavac
- Department of Biomedical Engineering and Mechanics, Virginia Tech University Blacksburg, VA, USA
| | - Pamela J VandeVord
- Department of Biomedical Engineering and Mechanics, Virginia Tech University Blacksburg, VA, USA
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VandeVord PJ, Leonardi ADC, Ritzel D. Bridging the Gap of Standardized Animals Models for Blast Neurotrauma: Methodology for Appropriate Experimental Testing. Methods Mol Biol 2016; 1462:101-18. [PMID: 27604715 DOI: 10.1007/978-1-4939-3816-2_7] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
Recent military combat has heightened awareness to the complexity of blast-related traumatic brain injuries (bTBI). Experiments using animal, cadaver, or biofidelic physical models remain the primary measures to investigate injury biomechanics as well as validate computational simulations, medical diagnostics and therapies, or protection technologies. However, blast injury research has seen a range of irregular and inconsistent experimental methods for simulating blast insults generating results which may be misleading, cannot be cross-correlated between laboratories, or referenced to any standard for exposure. Both the US Army Medical Research and Materiel Command and the National Institutes of Health have noted that there is a lack of standardized preclinical models of TBI. It is recommended that the blast injury research community converge on a consistent set of experimental procedures and reporting of blast test conditions. This chapter describes the blast conditions which can be recreated within a laboratory setting and methodology for testing in vivo models within the appropriate environment.
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Affiliation(s)
- Pamela J VandeVord
- Biomedical Engineering and Mechanics, Virginia Tech, 447 Kelly Hall, 325 Stanger St., Blacksburg, VA, 24061, USA.
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Bailey ZS, Hubbard WB, VandeVord PJ. Cellular Mechanisms and Behavioral Outcomes in Blast-Induced Neurotrauma: Comparing Experimental Setups. Methods Mol Biol 2016; 1462:119-138. [PMID: 27604716 DOI: 10.1007/978-1-4939-3816-2_8] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
Blast-induced neurotrauma (BINT) has increased in incidence over the past decades and can result in cognitive issues that have debilitating consequences. The exact primary and secondary mechanisms of injury have not been elucidated and appearance of cellular injury can vary based on many factors, such as blast overpressure magnitude and duration. Many methodologies to study blast neurotrauma have been employed, ranging from open-field explosives to experimental shock tubes for producing free-field blast waves. While there are benefits to the various methods, certain specifications need to be accounted for in order to properly examine BINT. Primary cell injury mechanisms, occurring as a direct result of the blast wave, have been identified in several studies and include cerebral vascular damage, blood-brain barrier disruption, axonal injury, and cytoskeletal damage. Secondary cell injury mechanisms, triggered subsequent to the initial insult, result in the activation of several molecular cascades and can include, but are not limited to, neuroinflammation and oxidative stress. The collective result of these secondary injuries can lead to functional deficits. Behavioral measures examining motor function, anxiety traits, and cognition/memory problems have been utilized to determine the level of injury severity. While cellular injury mechanisms have been identified following blast exposure, the various experimental models present both concurrent and conflicting results. Furthermore, the temporal response and progression of pathology after blast exposure have yet to be detailed and remain unclear due to limited resemblance of methodologies. This chapter summarizes the current state of blast neuropathology and emphasizes the need for a standardized preclinical model of blast neurotrauma.
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Affiliation(s)
- Zachary S Bailey
- School of Biomedical Engineering and Sciences, Virginia Tech, 447 Kelly Hall, 325 Stanger Street, Blacksburg, VA, 24061, USA
| | - W Brad Hubbard
- School of Biomedical Engineering and Sciences, Virginia Tech, 447 Kelly Hall, 325 Stanger Street, Blacksburg, VA, 24061, USA
| | - Pamela J VandeVord
- School of Biomedical Engineering and Sciences, Virginia Tech, 447 Kelly Hall, 325 Stanger Street, Blacksburg, VA, 24061, USA.
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Ameliorative Effects of Antioxidants on the Hippocampal Accumulation of Pathologic Tau in a Rat Model of Blast-Induced Traumatic Brain Injury. OXIDATIVE MEDICINE AND CELLULAR LONGEVITY 2015; 2016:4159357. [PMID: 27034735 PMCID: PMC4806690 DOI: 10.1155/2016/4159357] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/22/2015] [Accepted: 09/15/2015] [Indexed: 01/22/2023]
Abstract
Traumatic brain injury (TBI) can lead to early onset dementia and other related neurodegenerative diseases. We previously demonstrated that damage to the central auditory pathway resulting from blast-induced TBI (bTBI) could be significantly attenuated by a combinatorial antioxidant treatment regimen. In the current study, we examined the localization patterns of normal Tau and the potential blast-induced accumulation of neurotoxic variants of this microtubule-associated protein that are believed to potentiate the neurodegenerative effects associated with synaptic dysfunction in the hippocampus following three successive blast overpressure exposures in nontransgenic rats. We observed a marked increase in the number of both hyperphosphorylated and oligomeric Tau-positive hilar mossy cells and somatic accumulation of endogenous Tau in oligodendrocytes in the hippocampus. Remarkably, a combinatorial regimen of 2,4-disulfonyl α-phenyl tertiary butyl nitrone (HPN-07) and N-acetylcysteine (NAC) resulted in striking reductions in the numbers of both mossy cells and oligodendrocytes positively labeled for these pathological Tau immunoreactivity patterns in response to bTBI. This treatment strategy represents a promising therapeutic approach for simultaneously reducing or eliminating both primary auditory injury and nonauditory changes associated with bTBI-induced hippocampal neurodegeneration.
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Alekseeva OS, Gusel’nikova VV, Beznin GV, Korzhevskii DE. Prospects for the application of neun nuclear protein as a marker of the functional state of nerve cells in vertebrates. J EVOL BIOCHEM PHYS+ 2015. [DOI: 10.1134/s0022093015050014] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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31
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Sajja VSSS, Hubbard WB, Hall CS, Ghoddoussi F, Galloway MP, VandeVord PJ. Enduring deficits in memory and neuronal pathology after blast-induced traumatic brain injury. Sci Rep 2015; 5:15075. [PMID: 26537106 PMCID: PMC4633584 DOI: 10.1038/srep15075] [Citation(s) in RCA: 47] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2015] [Accepted: 09/15/2015] [Indexed: 01/06/2023] Open
Abstract
Few preclinical studies have assessed the long-term neuropathology and behavioral deficits after sustaining blast-induced neurotrauma (BINT). Previous studies have shown extensive astrogliosis and cell death at acute stages (<7 days) but the temporal response at a chronic stage has yet to be ascertained. Here, we used behavioral assays, immmunohistochemistry and neurochemistry in limbic areas such as the amygdala (Amy), Hippocampus (Hipp), nucleus accumbens (Nac), and prefrontal cortex (PFC), to determine the long-term effects of a single blast exposure. Behavioral results identified elevated avoidance behavior and decreased short-term memory at either one or three months after a single blast event. At three months after BINT, markers for neurodegeneration (FJB) and microglia activation (Iba-1) increased while index of mature neurons (NeuN) significantly decreased in all brain regions examined. Gliosis (GFAP) increased in all regions except the Nac but only PFC was positive for apoptosis (caspase-3). At three months, tau was selectively elevated in the PFC and Hipp whereas α-synuclein transiently increased in the Hipp at one month after blast exposure. The composite neurochemical measure, myo-inositol+glycine/creatine, was consistently increased in each brain region three months following blast. Overall, a single blast event resulted in enduring long-term effects on behavior and neuropathological sequelae.
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Affiliation(s)
| | - W Brad Hubbard
- School of Biomedical Engineering and Sciences, Virginia Polytechnic and State University, Blacksburg, VA
| | - Christina S Hall
- School of Biomedical Engineering and Sciences, Virginia Polytechnic and State University, Blacksburg, VA
| | - Farhad Ghoddoussi
- Department of Anesthesiology, Wayne State University School of Medicine, Detroit, MI
| | - Matthew P Galloway
- Department of Anesthesiology, Wayne State University School of Medicine, Detroit, MI.,Department of Psychiatry, Wayne State University School of Medicine, Detroit, MI
| | - Pamela J VandeVord
- School of Biomedical Engineering and Sciences, Virginia Polytechnic and State University, Blacksburg, VA.,Salem VA Medical Center, Research &Development Service, Salem, VA, USA
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VandeVord PJ, Sajja VSSS, Ereifej E, Hermundstad A, Mao S, Hadden TJ. Chronic Hormonal Imbalance and Adipose Redistribution Is Associated with Hypothalamic Neuropathology following Blast Exposure. J Neurotrauma 2015; 33:82-8. [PMID: 26274838 DOI: 10.1089/neu.2014.3786] [Citation(s) in RCA: 6] [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
Endocrine disorders have been shown to be a consequence of blast traumatic brain injury in soldiers returning from military conflicts. Hormone deficiency and adrenocorticotropic hormone (ACTH) dysfunction can lead to symptoms such as fatigue, anxiety, irritability, insomnia, sexual dysfunction, and decreased quality of life. Given these changes following blast exposure, the current study focused on investigating chronic pathology within the hypothalamus following blast, in addition to systemic effects. An established rodent model of blast neurotrauma was used to induce mild blast-induced neurotrauma. Adipose tissue, blood, and brain samples were collected at one and three months following a single blast exposure. Adipose tissue and blood were evaluated for changes in ACTH, adiponectin, C-reactive protein, glial fibrillary acidic protein, interleukin (IL)-1β, and leptin. The hypothalamus was evaluated for injury using immunohistochemical techniques. The results demonstrated that the weight of the blast animals was significantly less, compared with the sham group. The slower rate of increase in their weight was associated with changes in ACTH, IL-1β, and leptin levels. Further, histological analysis indicated elevated levels of cleaved caspase-3 positive cells within the hypothalamus. The data suggest that long-term outcomes of brain injury occurring from blast exposure include dysfunction of the hypothalamus, which leads to compromised hormonal function, elevated biological stress-related hormones, and subsequent adipose tissue remodeling.
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Affiliation(s)
- Pamela J VandeVord
- 1 School of Biomedical Engineering and Sciences, Virginia Tech , Blacksburg, Virginia
| | | | - Evon Ereifej
- 1 School of Biomedical Engineering and Sciences, Virginia Tech , Blacksburg, Virginia
| | - Amy Hermundstad
- 1 School of Biomedical Engineering and Sciences, Virginia Tech , Blacksburg, Virginia
| | - Shijie Mao
- 1 School of Biomedical Engineering and Sciences, Virginia Tech , Blacksburg, Virginia
| | - Timothy J Hadden
- 2 Research Services, John D. Dingell VA Medical Center , Detroit, Michigan
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Bailey ZS, Grinter MB, De La Torre Campos D, VandeVord PJ. Blast induced neurotrauma causes overpressure dependent changes to the DNA methylation equilibrium. Neurosci Lett 2015; 604:119-23. [PMID: 26232681 DOI: 10.1016/j.neulet.2015.07.035] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2015] [Revised: 07/14/2015] [Accepted: 07/26/2015] [Indexed: 01/01/2023]
Abstract
Traumatic brain injury (TBI) has a high prevalence in our society and often leads to morbidity and mortality. TBI also occurs frequently in a military setting where exposure to blast waves is common. Abnormal gene expression involved with oxidative stress, inflammation and neuronal apoptosis has been well documented following blast induced neurotrauma (BINT). Altered epigenetic transcriptional regulation through DNA methylation has been implicated in the pathology of the injury. Imbalance between DNA methylation and DNA demethylation may lead to altered methylation patterns and subsequent changes in gene transcription. DNA methyltransferase enzymes (DNMT1, DNMT3a, and DNMT3b) are responsible for the addition of methyl groups to DNA, DNA methylation. Whereas the combined function of ten-eleven translocation enzymes (TET1, TET2, and TET3) and thymine-DNA glycosylase (TDG) result in the removal of methyl groups from DNA, DNA demethylation. We used an established rodent model of BINT to assess changes in DNA methylation and demethylation enzymes following injury. Three different blast overpressures were investigated (10, 17 and 23psi). Gene expression was investigated in the prefrontal cortex and hippocampus two weeks following injury. We observed DNMT, TET and TDG expression changes between pressure groups and brain regions. The hippocampus was more vulnerable to enzyme expression changes than the prefrontal cortex, which correlated with aberrant DNA methylation. A significant negative correlation was found between global DNA methylation and the magnitude of blast overpressure exposure. Through transcriptional regulation, altered DNA methylation patterns may offer insight into the characteristic outcomes associated with the injury pathology including inflammation, oxidative stress and apoptosis. As such, these enzymes may be important targets to future therapeutic intervention strategies.
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Affiliation(s)
- Zachary S Bailey
- Biomedical Engineering and Mechanics, Virginia Tech, Blacksburg, VA 24060, USA
| | - Michael B Grinter
- Biomedical Engineering and Mechanics, Virginia Tech, Blacksburg, VA 24060, USA
| | | | - Pamela J VandeVord
- Biomedical Engineering and Mechanics, Virginia Tech, Blacksburg, VA 24060, USA; Salem Veterans Affairs Medical Center, Salem, VA 24153, USA.
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Sachs F, Sivaselvan MV. Cell volume control in three dimensions: Water movement without solute movement. ACTA ACUST UNITED AC 2015; 145:373-80. [PMID: 25870207 PMCID: PMC4411252 DOI: 10.1085/jgp.201411297] [Citation(s) in RCA: 42] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
Affiliation(s)
- Frederick Sachs
- Department of Physiology and Biophysics and Department of Civil, Structural and Environmental Engineering, University at Buffalo, The State University of New York, Buffalo, NY 14260
| | - Mettupalayam V Sivaselvan
- Department of Physiology and Biophysics and Department of Civil, Structural and Environmental Engineering, University at Buffalo, The State University of New York, Buffalo, NY 14260
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35
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Elder GA, Gama Sosa MA, De Gasperi R, Stone JR, Dickstein DL, Haghighi F, Hof PR, Ahlers ST. Vascular and inflammatory factors in the pathophysiology of blast-induced brain injury. Front Neurol 2015; 6:48. [PMID: 25852632 PMCID: PMC4360816 DOI: 10.3389/fneur.2015.00048] [Citation(s) in RCA: 81] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2015] [Accepted: 02/23/2015] [Indexed: 11/13/2022] Open
Abstract
Blast-related traumatic brain injury (TBI) has received much recent attention because of its frequency in the conflicts in Iraq and Afghanistan. This renewed interest has led to a rapid expansion of clinical and animal studies related to blast. In humans, high-level blast exposure is associated with a prominent hemorrhagic component. In animal models, blast exerts a variety of effects on the nervous system including vascular and inflammatory effects that can be seen with even low-level blast exposures which produce minimal or no neuronal pathology. Acutely, blast exposure in animals causes prominent vasospasm and decreased cerebral blood flow along with blood-brain barrier breakdown and increased vascular permeability. Besides direct effects on the central nervous system, evidence supports a role for a thoracically mediated effect of blast; whereby, pressure waves transmitted through the systemic circulation damage the brain. Chronically, a vascular pathology has been observed that is associated with alterations of the vascular extracellular matrix. Sustained microglial and astroglial reactions occur after blast exposure. Markers of a central and peripheral inflammatory response are found for sustained periods after blast injury and include elevation of inflammatory cytokines and other inflammatory mediators. At low levels of blast exposure, a microvascular pathology has been observed in the presence of an otherwise normal brain parenchyma, suggesting that the vasculature may be selectively vulnerable to blast injury. Chronic immune activation in brain following vascular injury may lead to neurobehavioral changes in the absence of direct neuronal pathology. Strategies aimed at preventing or reversing vascular damage or modulating the immune response may improve the chronic neuropsychiatric symptoms associated with blast-related TBI.
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Affiliation(s)
- Gregory A Elder
- Neurology Service, James J. Peters Department of Veterans Affairs Medical Center , Bronx, NY , USA ; Department of Psychiatry, Icahn School of Medicine at Mount Sinai , New York, NY , USA ; Department of Neurology, Icahn School of Medicine at Mount Sinai , New York, NY , USA ; Friedman Brain Institute, Icahn School of Medicine at Mount Sinai , New York, NY , USA
| | - Miguel A Gama Sosa
- Department of Psychiatry, Icahn School of Medicine at Mount Sinai , New York, NY , USA ; Friedman Brain Institute, Icahn School of Medicine at Mount Sinai , New York, NY , USA ; Research and Development Service, James J. Peters Department of Veterans Affairs Medical Center , Bronx, NY , USA
| | - Rita De Gasperi
- Department of Psychiatry, Icahn School of Medicine at Mount Sinai , New York, NY , USA ; Friedman Brain Institute, Icahn School of Medicine at Mount Sinai , New York, NY , USA ; Research and Development Service, James J. Peters Department of Veterans Affairs Medical Center , Bronx, NY , USA
| | - James Radford Stone
- Department of Radiology and Medical Imaging, University of Virginia , Charlottesville, VA , USA ; Department of Neurosurgery, University of Virginia , Charlottesville, VA , USA
| | - Dara L Dickstein
- Friedman Brain Institute, Icahn School of Medicine at Mount Sinai , New York, NY , USA ; Fishberg Department of Neuroscience, Icahn School of Medicine at Mount Sinai , New York, NY , USA ; Department of Geriatrics and Palliative Care, Icahn School of Medicine at Mount Sinai , New York, NY , USA
| | - Fatemeh Haghighi
- Department of Psychiatry, Icahn School of Medicine at Mount Sinai , New York, NY , USA ; Friedman Brain Institute, Icahn School of Medicine at Mount Sinai , New York, NY , USA ; Research and Development Service, James J. Peters Department of Veterans Affairs Medical Center , Bronx, NY , USA ; Fishberg Department of Neuroscience, Icahn School of Medicine at Mount Sinai , New York, NY , USA
| | - Patrick R Hof
- Friedman Brain Institute, Icahn School of Medicine at Mount Sinai , New York, NY , USA ; Fishberg Department of Neuroscience, Icahn School of Medicine at Mount Sinai , New York, NY , USA ; Department of Geriatrics and Palliative Care, Icahn School of Medicine at Mount Sinai , New York, NY , USA
| | - Stephen T Ahlers
- Department of Neurotrauma, Operational and Undersea Medicine Directorate, Naval Medical Research Center , Silver Spring, MD , USA
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Miller AP, Shah AS, Aperi BV, Budde MD, Pintar FA, Tarima S, Kurpad SN, Stemper BD, Glavaski-Joksimovic A. Effects of blast overpressure on neurons and glial cells in rat organotypic hippocampal slice cultures. Front Neurol 2015; 6:20. [PMID: 25729377 PMCID: PMC4325926 DOI: 10.3389/fneur.2015.00020] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2014] [Accepted: 01/25/2015] [Indexed: 11/13/2022] Open
Abstract
Due to recent involvement in military conflicts, and an increase in the use of explosives, there has been an escalation in the incidence of blast-induced traumatic brain injury (bTBI) among US military personnel. Having a better understanding of the cellular and molecular cascade of events in bTBI is prerequisite for the development of an effective therapy that currently is unavailable. The present study utilized organotypic hippocampal slice cultures (OHCs) exposed to blast overpressures of 150 kPa (low) and 280 kPa (high) as an in vitro bTBI model. Using this model, we further characterized the cellular effects of the blast injury. Blast-evoked cell death was visualized by a propidium iodide (PI) uptake assay as early as 2 h post-injury. Quantification of PI staining in the cornu Ammonis 1 and 3 (CA1 and CA3) and the dentate gyrus regions of the hippocampus at 2, 24, 48, and 72 h following blast exposure revealed significant time dependent effects. OHCs exposed to 150 kPa demonstrated a slow increase in cell death plateauing between 24 and 48 h, while OHCs from the high-blast group exhibited a rapid increase in cell death already at 2 h, peaking at ~24 h post-injury. Measurements of lactate dehydrogenase release into the culture medium also revealed a significant increase in cell lysis in both low- and high-blast groups compared to sham controls. OHCs were fixed at 72 h post-injury and immunostained for markers against neurons, astrocytes, and microglia. Labeling OHCs with PI, neuronal, and glial markers revealed that the blast-evoked extensive neuronal death and to a lesser extent loss of glial cells. Furthermore, our data demonstrated activation of astrocytes and microglial cells in low- and high-blasted OHCs, which reached a statistically significant difference in the high-blast group. These data confirmed that our in vitro bTBI model is a useful tool for studying cellular and molecular changes after blast exposure.
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Affiliation(s)
- Anna P Miller
- Department of Neurosurgery, Medical College of Wisconsin , Milwaukee, WI , USA ; Department of Cell Biology, Neurobiology and Anatomy, Medical College of Wisconsin , Milwaukee, WI , USA ; Clement J. Zablocki Veterans Affairs Medical Center , Milwaukee, WI , USA
| | - Alok S Shah
- Department of Neurosurgery, Medical College of Wisconsin , Milwaukee, WI , USA ; Clement J. Zablocki Veterans Affairs Medical Center , Milwaukee, WI , USA
| | - Brandy V Aperi
- Department of Neurosurgery, Medical College of Wisconsin , Milwaukee, WI , USA ; Clement J. Zablocki Veterans Affairs Medical Center , Milwaukee, WI , USA
| | - Matthew D Budde
- Department of Neurosurgery, Medical College of Wisconsin , Milwaukee, WI , USA ; Clement J. Zablocki Veterans Affairs Medical Center , Milwaukee, WI , USA
| | - Frank A Pintar
- Department of Neurosurgery, Medical College of Wisconsin , Milwaukee, WI , USA ; Department of Cell Biology, Neurobiology and Anatomy, Medical College of Wisconsin , Milwaukee, WI , USA ; Clement J. Zablocki Veterans Affairs Medical Center , Milwaukee, WI , USA
| | - Sergey Tarima
- Division of Biostatistics, Institute for Health and Society, Medical College of Wisconsin , Milwaukee, WI , USA
| | - Shekar N Kurpad
- Department of Neurosurgery, Medical College of Wisconsin , Milwaukee, WI , USA ; Department of Cell Biology, Neurobiology and Anatomy, Medical College of Wisconsin , Milwaukee, WI , USA ; Clement J. Zablocki Veterans Affairs Medical Center , Milwaukee, WI , USA
| | - Brian D Stemper
- Department of Neurosurgery, Medical College of Wisconsin , Milwaukee, WI , USA ; Clement J. Zablocki Veterans Affairs Medical Center , Milwaukee, WI , USA
| | - Aleksandra Glavaski-Joksimovic
- Department of Neurosurgery, Medical College of Wisconsin , Milwaukee, WI , USA ; Department of Cell Biology, Neurobiology and Anatomy, Medical College of Wisconsin , Milwaukee, WI , USA ; Clement J. Zablocki Veterans Affairs Medical Center , Milwaukee, WI , USA
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Shetty AK, Mishra V, Kodali M, Hattiangady B. Blood brain barrier dysfunction and delayed neurological deficits in mild traumatic brain injury induced by blast shock waves. Front Cell Neurosci 2014; 8:232. [PMID: 25165433 PMCID: PMC4131244 DOI: 10.3389/fncel.2014.00232] [Citation(s) in RCA: 63] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2014] [Accepted: 07/24/2014] [Indexed: 11/13/2022] Open
Abstract
Mild traumatic brain injury (mTBI) resulting from exposure to blast shock waves (BSWs) is one of the most predominant causes of illnesses among veterans who served in the recent Iraq and Afghanistan wars. Such mTBI can also happen to civilians if exposed to shock waves of bomb attacks by terrorists. While cognitive problems, memory dysfunction, depression, anxiety and diffuse white matter injury have been observed at both early and/or delayed time-points, an initial brain pathology resulting from exposure to BSWs appears to be the dysfunction or disruption of the blood-brain barrier (BBB). Studies in animal models suggest that exposure to relatively milder BSWs (123 kPa) initially induces free radical generating enzymes in and around brain capillaries, which enhances oxidative stress resulting in loss of tight junction (TJ) proteins, edema formation, and leakiness of BBB with disruption or loss of its components pericytes and astrocyte end-feet. On the other hand, exposure to more intense BSWs (145-323 kPa) causes acute disruption of the BBB with vascular lesions in the brain. Both of these scenarios lead to apoptosis of endothelial and neural cells and neuroinflammation in and around capillaries, which may progress into chronic traumatic encephalopathy (CTE) and/or a variety of neurological impairments, depending on brain regions that are afflicted with such lesions. This review discusses studies that examined alterations in the brain milieu causing dysfunction or disruption of the BBB and neuroinflammation following exposure to different intensities of BSWs. Furthermore, potential of early intervention strategies capable of easing oxidative stress, repairing the BBB or blocking inflammation for minimizing delayed neurological deficits resulting from exposure to BSWs is conferred.
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Affiliation(s)
- Ashok K Shetty
- Texas A&M Health Science Center College of Medicine at Scott & White, Institute for Regenerative Medicine Temple, TX, USA ; Department of Molecular and Cellular Medicine, Texas A&M Health Science Center College of Medicine College Station, TX, USA ; Research Service, Olin E. Teague Veterans Affairs Medical Center, Central Texas Veterans Health Care System Temple, TX, USA
| | - Vikas Mishra
- Texas A&M Health Science Center College of Medicine at Scott & White, Institute for Regenerative Medicine Temple, TX, USA ; Department of Molecular and Cellular Medicine, Texas A&M Health Science Center College of Medicine College Station, TX, USA ; Research Service, Olin E. Teague Veterans Affairs Medical Center, Central Texas Veterans Health Care System Temple, TX, USA
| | - Maheedhar Kodali
- Texas A&M Health Science Center College of Medicine at Scott & White, Institute for Regenerative Medicine Temple, TX, USA ; Department of Molecular and Cellular Medicine, Texas A&M Health Science Center College of Medicine College Station, TX, USA ; Research Service, Olin E. Teague Veterans Affairs Medical Center, Central Texas Veterans Health Care System Temple, TX, USA
| | - Bharathi Hattiangady
- Texas A&M Health Science Center College of Medicine at Scott & White, Institute for Regenerative Medicine Temple, TX, USA ; Department of Molecular and Cellular Medicine, Texas A&M Health Science Center College of Medicine College Station, TX, USA ; Research Service, Olin E. Teague Veterans Affairs Medical Center, Central Texas Veterans Health Care System Temple, TX, USA
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