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Talwalkar A, Haden G, Duncan KA. Chondroitin sulfate proteoglycans mRNA expression and degradation in the zebra finch following traumatic brain injury. J Chem Neuroanat 2024; 138:102418. [PMID: 38621597 DOI: 10.1016/j.jchemneu.2024.102418] [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] [Received: 01/04/2024] [Revised: 04/01/2024] [Accepted: 04/03/2024] [Indexed: 04/17/2024]
Abstract
Traumatic brain injury (TBI) is one of the leading causes of fatality and disability worldwide. From minutes to months following damage, injury can result in a complex pathophysiology that can lead to temporary or permanent deficits including an array of neurodegenerative symptoms. These changes can include behavioral dysregulation, memory dysfunctions, and mood changes including depression. The nature and severity of impairments resulting from TBIs vary widely given the range of injury type, location, and extent of brain tissue involved. In response to the injury, the brain induces structural and functional changes to promote repair and minimize injury size. Despite its high prevalence, effective treatment strategies for TBI are limited. PNNs are part of the neuronal extracellular matrix (ECM) that mediate synaptic stabilization in the adult brain and thus neuroplasticity. They are associated mostly with inhibitory GABAergic interneurons and are thought to be responsible for maintaining the excitatory/inhibitory balance of the brain. The major structural components of PNNs include multiple chondroitin sulfate proteoglycans (CSPGs) as well as other structural proteins. Here we examine the effects of injury on CSPG expression, specifically around the changes in the side change moieties. To investigate CSPG expression following injury, adult male and female zebra finches received either a bilateral penetrating, or no injury and qPCR analysis and immunohistochemistry for components of the CSPGs were examined at 1- or 7-days post-injury. Next, to determine if CSPGs and thus PNNs should be a target for therapeutic intervention, CSPG side chains were degraded at the time of injury with chondroitinase ABC (ChABC) CSPGs moieties were examined. Additionally, GABA receptor mRNA and aromatase mRNA expression was quantified following CSPG degradation as they have been implicated in neuronal survival and neurogenesis. Our data indicate the CSPG moieties change following injury, potentially allowing for a brief period of synaptic reorganization, and that treatments that target CSPG side chains are successful in further targeting this brief critical period by decreasing GABA mRNA receptor expression, but also decreasing aromatase expression.
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Affiliation(s)
- Adam Talwalkar
- Program in Biochemistry, Vassar College, Poughkeepsie, NY 12604, USA
| | - Gage Haden
- Department of Biology, Vassar College, Poughkeepsie, NY 12604, USA
| | - Kelli A Duncan
- Department of Biology, Vassar College, Poughkeepsie, NY 12604, USA; Program in Neuroscience and Behavior, Vassar College, Poughkeepsie, NY 12604, USA.
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Sgro M, Kodila ZN, Li C, Carmichael I, Warren S, Reichelt AC, Yamakawa GR, Mychasiuk R. Microbiome depletion prior to repeat mild TBI differentially alters social deficits and prefrontal cortex plasticity in adolescent and adult rats. iScience 2024; 27:109395. [PMID: 38510122 PMCID: PMC10952042 DOI: 10.1016/j.isci.2024.109395] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2023] [Revised: 11/21/2023] [Accepted: 02/28/2024] [Indexed: 03/22/2024] Open
Abstract
Although aging, repeat mild traumatic brain injury (RmTBI), and microbiome modifications independently change social behavior, there has been no investigation into their cumulative effects on social behavior and neuroplasticity within the prefrontal cortex. Therefore, we examined how microbiome depletion prior to RmTBI affected social behavior and neuroplasticity in adolescent and adult rats. Play, temperament analysis, elevated plus maze, and the hot/cold plate assessed socio-emotional function. Analyses of perineuronal nets (PNNs) and parvalbumin (PV) interneurons was completed. Social-emotional deficits were more pronounced in adults, with microbiome depletion attenuating social behavior deficits associated with RmTBI in both age groups. Microbiome depletion increased branch length and PNN arborization within the PFC but decreased the overall number of PNNs. Adults and males were more vulnerable to RmTBI. Interestingly, microbiome depletion may have attenuated the changes to neuroplasticity and subsequent social deficits, suggesting that the microbiome is a viable, but age-specific, target for RmTBI therapeutics.
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Affiliation(s)
- Marissa Sgro
- Department of Neuroscience, Central Clinical School, Monash University, Melbourne, VIC 3004, Australia
| | - Zoe N. Kodila
- Department of Neuroscience, Central Clinical School, Monash University, Melbourne, VIC 3004, Australia
| | - Crystal Li
- Department of Neuroscience, Central Clinical School, Monash University, Melbourne, VIC 3004, Australia
| | - Irena Carmichael
- Monash Micro Imaging, Central Clinical School, Monash University, Melbourne, VIC 3004, Australia
| | - Samantha Warren
- Monash Micro Imaging, Central Clinical School, Monash University, Melbourne, VIC 3004, Australia
| | - Amy C. Reichelt
- School of Biomedicine, University of Adelaide, Adelaide, SA 5005, Australia
| | - Glenn R. Yamakawa
- Department of Neuroscience, Central Clinical School, Monash University, Melbourne, VIC 3004, Australia
| | - Richelle Mychasiuk
- Department of Neuroscience, Central Clinical School, Monash University, Melbourne, VIC 3004, Australia
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Vita SM, Cruise SC, Gilpin NW, Molina PE. Histological comparison of repeated mild weight drop and lateral fluid percussion injury models of traumatic brain injury (TBI) in female and male rats. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.01.31.578177. [PMID: 38352449 PMCID: PMC10862833 DOI: 10.1101/2024.01.31.578177] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2024]
Abstract
Traumatic brain injury (TBI) heterogeneity has led to the development of several preclinical models, each modeling a distinct subset of outcomes. Selection of an injury model should be guided by the research question and the specific outcome measures of interest. Consequently, there is a need for conducting direct comparisons of different TBI models. Here, we used immunohistochemistry to directly compare the outcomes from two common models, lateral fluid percussion (LFP) and repeat mild weight drop (rmWD), on neuropathology in adult female and male Wistar rats. Specifically, we used immunohistochemistry to measure the effects of LFP and rmWD on cerebrovascular and tight junction disruption, inflammatory markers, mature neurons and perineuronal nets in the cortical site of injury, cortex adjacent to injury, dentate gyrus, and the CA2/3 area of the hippocampus. Animals were randomized into either LFP or rmWD groups. The LFP group received a craniotomy prior to LFP (or corresponding sham procedure) three days later, while rmWD animals underwent either weight drop or sham (isoflurane only) on each of those four days. After a recovery period of 7 days, animals were euthanized, and brains were harvested for analysis of RECA-1, claudin-5, GFAP, Iba-1, CD-68, NeuN, and wisteria floribunda lectin. Overall, our observations revealed that the most significant disruptions were evident in response to LFP, followed by craniotomy-only, while rmWD animals showed the least residual changes compared to isoflurane-only controls. These findings support consideration of rmWD as a mild, transient injury. LFP leads to longer-lasting disruptions that are more closely associated with a moderate TBI. We further show that both craniotomy and LFP produced greater disruptions in females relative to males at 7 days post-injury. These findings support the inclusion of a time-matched experimentally-naïve or anesthesia-only control group in preclinical TBI research to enhance the validity of data interpretation and conclusions.
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Mohammed Butt A, Rupareliya V, Hariharan A, Kumar H. Building a pathway to recovery: Targeting ECM remodeling in CNS injuries. Brain Res 2023; 1819:148533. [PMID: 37586675 DOI: 10.1016/j.brainres.2023.148533] [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] [Received: 05/25/2023] [Revised: 08/07/2023] [Accepted: 08/09/2023] [Indexed: 08/18/2023]
Abstract
Extracellular matrix (ECM) is a complex and dynamic network of proteoglycans, proteins, and other macromolecules that surrounds cells in tissues. The ECM provides structural support to cells and plays a critical role in regulating various cellular functions. ECM remodeling is a dynamic process involving the breakdown and reconstruction of the ECM. This process occurs naturally during tissue growth, wound healing, and tissue repair. However, in the context of central nervous system (CNS) injuries, dysregulated ECM remodeling can lead to the formation of fibrotic and glial scars. CNS injuries encompass various traumatic events, including concussions and fractures. Following CNS trauma, the formation of glial and fibrotic scars becomes prominent. Glial scars primarily consist of reactive astrocytes, while fibrotic scars are characterized by an abundance of ECM proteins. ECM remodeling plays a pivotal and tightly regulated role in the development of these scars after spinal cord and brain injuries. Various factors like ECM components, ECM remodeling enzymes, cell surface receptors of ECM molecules, and downstream pathways of ECM molecules are responsible for the remodeling of the ECM. The aim of this review article is to explore the changes in ECM during normal physiological conditions and following CNS injuries. Additionally, we discuss various approaches that target various factors responsible for ECM remodeling, with a focus on promoting axon regeneration and functional recovery after CNS injuries. By targeting ECM remodeling, it may be possible to enhance axonal regeneration and facilitate functional recovery after CNS injuries.
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Affiliation(s)
- Ayub Mohammed Butt
- Department of Pharmacology and Toxicology, National Institute of Pharmaceutical Education and Research (NIPER)-Ahmedabad, Gandhinagar, Gujarat, India
| | - Vimal Rupareliya
- Department of Pharmacology and Toxicology, National Institute of Pharmaceutical Education and Research (NIPER)-Ahmedabad, Gandhinagar, Gujarat, India
| | - A Hariharan
- Department of Pharmacology and Toxicology, National Institute of Pharmaceutical Education and Research (NIPER)-Ahmedabad, Gandhinagar, Gujarat, India
| | - Hemant Kumar
- Department of Pharmacology and Toxicology, National Institute of Pharmaceutical Education and Research (NIPER)-Ahmedabad, Gandhinagar, Gujarat, India.
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Nakuci J, McGuire M, Schweser F, Poulsen D, Muldoon SF. Differential Patterns of Change in Brain Connectivity Resulting from Severe Traumatic Brain Injury. Brain Connect 2022; 12:799-811. [PMID: 35302399 PMCID: PMC9805864 DOI: 10.1089/brain.2021.0168] [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] [Indexed: 01/13/2023] Open
Abstract
Background: Traumatic brain injury (TBI) damages white matter tracts, disrupting brain network structure and communication. There exists a wide heterogeneity in the pattern of structural damage associated with injury, as well as a large heterogeneity in behavioral outcomes. However, little is known about the relationship between changes in network connectivity and clinical outcomes. Materials and Methods: We utilize the rat lateral fluid-percussion injury model of severe TBI to study differences in brain connectivity in 8 animals that received the insult and 11 animals that received only a craniectomy. Diffusion tensor imaging is performed 5 weeks after the injury and network theory is used to investigate changes in white matter connectivity. Results: We find that (1) global network measures are not able to distinguish between healthy and injured animals; (2) injury induced alterations predominantly exist in a subset of connections (subnetworks) distributed throughout the brain; and (3) injured animals can be divided into subgroups based on changes in network motifs-measures of local structural connectivity. In addition, alterations in predicted functional connectivity indicate that the subgroups have different propensities to synchronize brain activity, which could relate to the heterogeneity of clinical outcomes. Discussion: These results suggest that network measures can be used to quantify progressive changes in brain connectivity due to injury and differentiate among subpopulations with similar injuries, but different pathological trajectories.
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Affiliation(s)
- Johan Nakuci
- Neuroscience Program, University at Buffalo, SUNY, Buffalo, New York, USA
| | - Matthew McGuire
- Neuroscience Program, University at Buffalo, SUNY, Buffalo, New York, USA
- Department of Neurosurgery, University at Buffalo, SUNY, Buffalo, New York, USA
| | - Ferdinand Schweser
- Buffalo Neuroimaging Analysis Center, Department of Neurology, School of Medicine and Biomedical Sciences, University at Buffalo, SUNY, Buffalo, New York, USA
- Center for Biomedical Imaging, Clinical and Translational Science Institute, University at Buffalo, SUNY, Buffalo, New York, USA
| | - David Poulsen
- Department of Neurosurgery, University at Buffalo, SUNY, Buffalo, New York, USA
| | - Sarah F. Muldoon
- Neuroscience Program, University at Buffalo, SUNY, Buffalo, New York, USA
- Department of Mathematics and CDSE Program, University at Buffalo, SUNY, Buffalo, New York, USA
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Gilmore N, Katz DI, Kiran S. Acquired Brain Injury in Adults: A Review of Pathophysiology, Recovery, and Rehabilitation. ACTA ACUST UNITED AC 2021; 6:714-727. [PMID: 34746412 DOI: 10.1044/2021_persp-21-00013] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Purpose To summarize existing literature from a range of fields (i.e., neurology, neuropsychology, neuroscience, neuroimaging, rehabilitation, speech-language pathology) that is relevant to the development and/or revision of cognitive rehabilitation programs for individuals with acquired brain injury (ABI) and in particular, for young adults. Method This paper reviews a range of ABI-associated topics including: 1) mechanisms of injury; 2) biological, individual-specific, and behavioral drivers of recovery; and 3) current methods of cognitive rehabilitation. It then narrows focus to young adults, a frequently affected and growing population to sustain ABI. The paper concludes by providing: 1) suggestions for key components of cognitive rehabilitation for young adults with ABI; 2) an example from our own research providing intensive academically-focused cognitive rehabilitation for young adults with ABI pursuing college; and 3) recommendations for future behavioral and neuroimaging studies in this area. Conclusions ABI is on the rise in the United States. Young adults have been sustaining ABI at higher rates over the past several decades. These injuries occur when they would otherwise be advancing their academic and career goals, making the cognitive deficits that often accompany ABI especially devastating for this group. Review of existing literature suggests cognitive rehabilitation programs that combine aspects of restorative, comprehensive, and contextualized approaches could promote recovery for young adults with ABI. Future intervention studies may benefit from including both behavioral and neural outcomes to best understand how principles of neuroplasticity- naturally embedded within many cognitive rehabilitation approaches-could be manipulated to promote cognitive recovery and long-lasting brain reorganization in this group.
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Affiliation(s)
- Natalie Gilmore
- Speech, Language and Hearing Sciences, Boston University, Boston, USA
| | - Douglas I Katz
- Neurology, Boston University School of Medicine, Boston, USA
| | - Swathi Kiran
- Speech, Language and Hearing Sciences, Boston University, Boston, USA
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Moulson AJ, Squair JW, Franklin RJM, Tetzlaff W, Assinck P. Diversity of Reactive Astrogliosis in CNS Pathology: Heterogeneity or Plasticity? Front Cell Neurosci 2021; 15:703810. [PMID: 34381334 PMCID: PMC8349991 DOI: 10.3389/fncel.2021.703810] [Citation(s) in RCA: 36] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2021] [Accepted: 07/02/2021] [Indexed: 01/02/2023] Open
Abstract
Astrocytes are essential for the development and homeostatic maintenance of the central nervous system (CNS). They are also critical players in the CNS injury response during which they undergo a process referred to as "reactive astrogliosis." Diversity in astrocyte morphology and gene expression, as revealed by transcriptional analysis, is well-recognized and has been reported in several CNS pathologies, including ischemic stroke, CNS demyelination, and traumatic injury. This diversity appears unique to the specific pathology, with significant variance across temporal, topographical, age, and sex-specific variables. Despite this, there is limited functional data corroborating this diversity. Furthermore, as reactive astrocytes display significant environmental-dependent plasticity and fate-mapping data on astrocyte subsets in the adult CNS is limited, it remains unclear whether this diversity represents heterogeneity or plasticity. As astrocytes are important for neuronal survival and CNS function post-injury, establishing to what extent this diversity reflects distinct established heterogeneous astrocyte subpopulations vs. environmentally dependent plasticity within established astrocyte subsets will be critical for guiding therapeutic development. To that end, we review the current state of knowledge on astrocyte diversity in the context of three representative CNS pathologies: ischemic stroke, demyelination, and traumatic injury, with the goal of identifying key limitations in our current knowledge and suggesting future areas of research needed to address them. We suggest that the majority of identified astrocyte diversity in CNS pathologies to date represents plasticity in response to dynamically changing post-injury environments as opposed to heterogeneity, an important consideration for the understanding of disease pathogenesis and the development of therapeutic interventions.
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Affiliation(s)
- Aaron J. Moulson
- Faculty of Medicine, University of British Columbia, Vancouver, BC, Canada
- International Collaboration on Repair Discoveries (ICORD), Vancouver, BC, Canada
| | - Jordan W. Squair
- Department of Clinical Neuroscience, Faculty of Life Sciences, Center for Neuroprosthetics and Brain Mind Institute, École Polytechnique Fédérale de Lausanne (EPFL), NeuroRestore, Lausanne University Hospital (CHUV), University of Lausanne (UNIL), Lausanne, Switzerland
| | - Robin J. M. Franklin
- Wellcome Trust - MRC Cambridge Stem Cell Institute, University of Cambridge, Cambridge, United Kingdom
| | - Wolfram Tetzlaff
- International Collaboration on Repair Discoveries (ICORD), Vancouver, BC, Canada
- Department of Zoology, University of British Columbia, Vancouver, BC, Canada
- Department of Surgery, University of British Columbia, Vancouver, BC, Canada
| | - Peggy Assinck
- Wellcome Trust - MRC Cambridge Stem Cell Institute, University of Cambridge, Cambridge, United Kingdom
- Centre for Regenerative Medicine, Institute for Regeneration and Repair, University of Edinburgh, Edinburgh, United Kingdom
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Zhao C, Deng Y, He Y, Huang X, Wang C, Li W. Decreased Level of Exosomal miR-5121 Released from Microglia Suppresses Neurite Outgrowth and Synapse Recovery of Neurons Following Traumatic Brain Injury. Neurotherapeutics 2021; 18:1273-1294. [PMID: 33475953 PMCID: PMC8423926 DOI: 10.1007/s13311-020-00999-z] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 12/20/2020] [Indexed: 10/22/2022] Open
Abstract
Activated microglia can suppress neurite outgrowth and synapse recovery in the acute stage following traumatic brain injury (TBI). However, the underlying mechanism has not been clearly elucidated. Exosomes derived from microglia have been reported to play a critical role in microglia-neuron interaction in healthy and pathological brains. Here, we aimed to investigate the role of microglia-derived exosomes in regulating neurite outgrowth and synapse recovery following TBI. In our study, exosomes derived from microglia were co-cultured with stretch-injured neurons in vitro and intravenously injected into mice that underwent fluid percussion injury (FPI) by tail vein injection in vivo. The results showed that microglia-derived exosomes could be absorbed by neurons in vitro and in vivo. Moreover, exosomes derived from stretch-injured microglia decreased the protein levels of GAP43, PSD-95, GluR1, and Synaptophysin and dendritic complexity in stretch-injured neurons in vitro, and reduced GAP43+ NEUN cell percentage and apical dendritic spine density in the pericontusion region in vivo. Motor coordination was also impaired in mice treated with stretch-injured microglia-derived exosomes after FPI. A microRNA microarray showed that the level of miR-5121 was decreased most greatly in exosomes derived from stretch-injured microglia. Overexpression of miR-5121 in stretch-injured microglia-derived exosomes partly reversed the suppression of neurite outgrowth and synapse recovery of neurons both in vitro and in vivo. Moreover, motor coordination in miR-5121 overexpressed exosomes treated mice was significantly improved after FPI. Following mechanistic study demonstrated that miR-5121 might promote neurite outgrowth and synapse recovery by directly targeting RGMa. In conclusion, our finding revealed a novel exosome-mediated mechanism of microglia-neuron interaction that suppressed neurite outgrowth and synapse recovery of neurons following TBI.
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Affiliation(s)
- Chengcheng Zhao
- Department of Neurosurgery, The First Affiliated Hospital of Shenzhen University, Shenzhen Second People's Hospital, 3002 Sungang Road, Shenzhen, Guangdong, China
- Guangdong Key Laboratory for Biomedical Measurements and Ultrasound Imaging, School of Biomedical Engineering, Shenzhen University Health Science Center, Shenzhen, Guangdong, China
| | - Yuefei Deng
- Department of Neurosurgery, Sun Yat-sen Memorial Hospital, Sun Yat-sen University, Guangzhou, Guangdong, China
| | - Yi He
- Department of Neurosurgery, The First Affiliated Hospital of Shenzhen University, Shenzhen Second People's Hospital, 3002 Sungang Road, Shenzhen, Guangdong, China
| | - Xianjian Huang
- Department of Neurosurgery, The First Affiliated Hospital of Shenzhen University, Shenzhen Second People's Hospital, 3002 Sungang Road, Shenzhen, Guangdong, China
| | - Chuanfang Wang
- Department of Neurosurgery and Neurosurgical Disease Research Centre, The Second Affiliated Hospital of Guangzhou Medical University, 250 Changgang East Road, Guangzhou, Guangdong, China.
| | - Weiping Li
- Department of Neurosurgery, The First Affiliated Hospital of Shenzhen University, Shenzhen Second People's Hospital, 3002 Sungang Road, Shenzhen, Guangdong, China.
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Dolenec P, Pilipović K, Janković T, Župan G. Pattern of Neuronal and Axonal Damage, Glial Response, and Synaptic Changes in Rat Cerebellum within the First Week following Traumatic Brain Injury. J Neuropathol Exp Neurol 2021; 79:1163-1182. [PMID: 33057716 DOI: 10.1093/jnen/nlaa111] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023] Open
Abstract
We examined damage and repair processes in the rat cerebellum within the first week following moderate traumatic brain injury (TBI) induced by lateral fluid percussion injury (LFPI) over the left parietal cortex. Rats were killed 1, 3, or 7 days after the injury or sham procedure. Fluoro-Jade B staining revealed 2 phases of neurodegenerative changes in the cell bodies and fibers: first, more focal, 1 day after the LFPI, and second, widespread, starting on post-injury day 3. Purkinje cell loss was detected in posterior lobule IX 1 day following LFPI. Apoptosis was observed in the cerebellar cortex, on days 1 and 7 following LFPI, and was not caspase- or apoptosis-inducing factor (AIF)-mediated. AIF immunostaining indicated axonal damage in the cerebellar white matter tracts 3- and 7-days post-injury. Significant astrocytosis and microgliosis were noticed on day 7 following LFPI at the sites of neuronal damage and loss. Immunohistochemical labeling with the presynaptic markers synaptophysin and growth-associated protein-43 revealed synaptic perturbations already on day 1 that were more pronounced at later time points following LFPI. These results provide new insights into pathophysiological alterations in the cerebellum and their mechanisms following cerebral TBI.
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Affiliation(s)
- Petra Dolenec
- Department of Pharmacology, Faculty of Medicine, University of Rijeka, Rijeka, Croatia
| | - Kristina Pilipović
- Department of Pharmacology, Faculty of Medicine, University of Rijeka, Rijeka, Croatia
| | - Tamara Janković
- Department of Pharmacology, Faculty of Medicine, University of Rijeka, Rijeka, Croatia
| | - Gordana Župan
- Department of Pharmacology, Faculty of Medicine, University of Rijeka, Rijeka, Croatia
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Lafrenaye A, Mondello S, Povlishock J, Gorse K, Walker S, Hayes R, Wang K, Kochanek PM. Operation Brain Trauma Therapy: An Exploratory Study of Levetiracetam Treatment Following Mild Traumatic Brain Injury in the Micro Pig. Front Neurol 2021; 11:586958. [PMID: 33584493 PMCID: PMC7874167 DOI: 10.3389/fneur.2020.586958] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2020] [Accepted: 12/03/2020] [Indexed: 12/18/2022] Open
Abstract
Operation brain trauma therapy (OBTT) is a drug- and biomarker-screening consortium intended to improve the quality of preclinical studies and provide a rigorous framework to increase the translational potential of experimental traumatic brain injury (TBI) treatments. Levetiracetam (LEV) is an antiepileptic agent that was the fifth drug tested by OBTT in three independent rodent models of moderate to severe TBI. To date, LEV has been the most promising drug tested by OBTT and was therefore advanced to testing in the pig. Adult male micro pigs were subjected to a mild central fluid percussion brain injury followed by a post-injury intravenous infusion of either 170 mg/kg LEV or vehicle. Systemic physiology was assessed throughout the post-injury period. Serial serum samples were obtained pre-injury as well as at 1 min, 30 min, 1 h, 3 h, and 6 h post-injury for a detailed analysis of the astroglial biomarker glial fibrillary acidic protein (GFAP) and ubiquitin carboxy-terminal hydrolase L1. Tissue was collected 6 h following injury for histological assessment of diffuse axonal injury using antibodies against the amyloid precursor protein (APP). The animals showed significant increases in circulating GFAP levels from baseline to 6 h post-injury; however, LEV treatment was associated with greater GFAP increases compared to the vehicle. There were no differences in the numbers of APP+ axonal swellings within the pig thalamus with LEV treatment; however, significant alterations in the morphological properties of the APP+ axonal swellings, including reduced swelling area and increased swelling roundness, were observed. Additionally, expression of the neurite outgrowth marker, growth-associated protein 43, was reduced in axonal swellings following LEV treatment, suggesting potential effects on axonal outgrowth that warrant further investigation.
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Affiliation(s)
- Audrey Lafrenaye
- Department of Anatomy and Neurobiology, Virginia Commonwealth University, Richmond, VA, United States
| | - Stefania Mondello
- Department of Biomedical and Dental Sciences and Morphofunctional Imaging, University of Messina, Messina, Italy.,Oasi Research Institute-IRCCS, Troina, Italy
| | - John Povlishock
- Department of Anatomy and Neurobiology, Virginia Commonwealth University, Richmond, VA, United States
| | - Karen Gorse
- Department of Anatomy and Neurobiology, Virginia Commonwealth University, Richmond, VA, United States
| | - Susan Walker
- Department of Anatomy and Neurobiology, Virginia Commonwealth University, Richmond, VA, United States
| | - Ronald Hayes
- Banyan Biomarkers, Inc., Alachua, FL, United States
| | - Kevin Wang
- Departments of Psychiatry & Neuroscience, Center for Neuroproteomics & Biomarkers Research, University of Florida, Gainesville, FL, United States
| | - Patrick M Kochanek
- Department of Critical Care Medicine, University of Pittsburgh School of Medicine, Pittsburgh, PA, United States
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11
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Acute damage to the blood–brain barrier and perineuronal net integrity in a clinically-relevant rat model of traumatic brain injury. Neuroreport 2020; 31:1167-1174. [PMID: 32991524 DOI: 10.1097/wnr.0000000000001531] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
Closed-head, frontal impacts in which the brain undergoes both lateral and rotational acceleration comprise the majority of human traumatic brain injury (TBI). Here, we utilize a clinically relevant model to examine the effects of a single concussion on aspects of brain integrity: the blood-brain barrier, the perineuronal nets (PNNs), and diffuse axonal injury. Adult, male Sprague-Dawley rats received either a frontal, closed-head concussive TBI, or no injury and were evaluated at 1- or 7-day post-injury. Using immunolabeling for albumin, we observed a significant increase in the permeability of the blood-brain barrier at 1-, but not 7-day post-injury. Breakdown of the PNN, as measured by the binding of wisteria floribunda, was observed at 1-day post-injury in the dorsal, lateral, and ventral cortices. This difference was resolved at 7-day. Finally, axonal injury was identified at both 1- and 7-day post-injury. This preclinical model of closed-head, frontal TBI presents a useful tool with which to understand better the acute pathophysiology of a single, frontal TBI.
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12
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Polsek D, Cash D, Veronese M, Ilic K, Wood TC, Milosevic M, Kalanj-Bognar S, Morrell MJ, Williams SCR, Gajovic S, Leschziner GD, Mitrecic D, Rosenzweig I. The innate immune toll-like-receptor-2 modulates the depressogenic and anorexiolytic neuroinflammatory response in obstructive sleep apnoea. Sci Rep 2020; 10:11475. [PMID: 32651433 PMCID: PMC7351955 DOI: 10.1038/s41598-020-68299-2] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2020] [Accepted: 06/16/2020] [Indexed: 12/19/2022] Open
Abstract
The increased awareness of obstructive sleep apnoea’s (OSA) links to Alzheimer’s disease and major psychiatric disorders has recently directed an intensified search for their potential shared mechanisms. We hypothesised that neuroinflammation and the microglial TLR2-system may act as a core process at the intersection of their pathophysiology. Moreover, we postulated that inflammatory-response might underlie development of key behavioural and neurostructural changes in OSA. Henceforth, we set out to investigate effects of 3 weeks’ exposure to chronic intermittent hypoxia in mice with or without functional TRL2 (TLR2+/+, C57BL/6-Tyrc-Brd-Tg(Tlr2-luc/gfp)Kri/Gaj;TLR2−/−,C57BL/6-Tlr2tm1Kir). By utilising multimodal imaging in this established model of OSA, a discernible neuroinflammatory response was demonstrated for the first time. The septal nuclei and forebrain were shown as the initial key seed-sites of the inflammatory cascade that led to wider structural changes in the associated neurocircuitry. Finally, the modulatory role for the functional TLR2-system was suggested in aetiology of depressive, anxious and anorexiolytic symptoms in OSA.
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Affiliation(s)
- Dora Polsek
- Sleep and Brain Plasticity Centre, Department of Neuroimaging, Institute of Psychiatry, Psychology and Neuroscience (IoPPN), King's College London (KCL), De Crespigny Park, Box 089, London, SE5 8AF, UK.,University of Zagreb School of Medicine, Croatian Institute for Brain Research, Zagreb, Croatia
| | - Diana Cash
- Sleep and Brain Plasticity Centre, Department of Neuroimaging, Institute of Psychiatry, Psychology and Neuroscience (IoPPN), King's College London (KCL), De Crespigny Park, Box 089, London, SE5 8AF, UK.,BRAIN, Department of Neuroimaging, KCL, London, UK
| | | | - Katarina Ilic
- University of Zagreb School of Medicine, Croatian Institute for Brain Research, Zagreb, Croatia
| | | | - Milan Milosevic
- School of Public Health, University of Zagreb School of Medicine, Zagreb, Croatia
| | - Svjetlana Kalanj-Bognar
- University of Zagreb School of Medicine, Croatian Institute for Brain Research, Zagreb, Croatia
| | - Mary J Morrell
- The National Heart and Lung Institute, Imperial College London, London, UK
| | | | - Srecko Gajovic
- University of Zagreb School of Medicine, Croatian Institute for Brain Research, Zagreb, Croatia
| | - Guy D Leschziner
- Sleep and Brain Plasticity Centre, Department of Neuroimaging, Institute of Psychiatry, Psychology and Neuroscience (IoPPN), King's College London (KCL), De Crespigny Park, Box 089, London, SE5 8AF, UK.,Department of Neurology, Guy's and St Thomas' Hospital (GSTT) and Clinical Neurosciences, KCL, London, UK.,Sleep Disorders Centre, GSTT, London, UK
| | - Dinko Mitrecic
- University of Zagreb School of Medicine, Croatian Institute for Brain Research, Zagreb, Croatia
| | - Ivana Rosenzweig
- Sleep and Brain Plasticity Centre, Department of Neuroimaging, Institute of Psychiatry, Psychology and Neuroscience (IoPPN), King's College London (KCL), De Crespigny Park, Box 089, London, SE5 8AF, UK. .,Sleep Disorders Centre, GSTT, London, UK.
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13
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Abstract
Microglia dynamically interact with neurons influencing the development, structure, and function of neuronal networks. Recent studies suggest microglia may also influence neuronal activity by physically interacting with axonal domains responsible for action potential initiation and propagation. However, the nature of these microglial process interactions is not well understood. Microglial-axonal contacts are present early in development and persist through adulthood, implicating microglial interactions in the regulation of axonal integrity in both the developing and mature central nervous system. Moreover, changes in microglial-axonal contact have been described in disease states such as multiple sclerosis (MS) and traumatic brain injury (TBI). Depending on the disease state, there are increased associations with specific axonal segments. In MS, there is enhanced contact with the axon initial segment and node of Ranvier, while, in TBI, microglia alter interactions with axons at the site of injury, as well as at the axon initial segment. In this article, we review the interactions of microglial processes with axonal segments, analyzing their associations with various axonal domains and how these interactions may differ between MS and TBI. Furthermore, we discuss potential functional consequences and molecular mechanisms of these interactions and how these may differ among various types of microglial-axonal interactions.
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Affiliation(s)
- Savannah D Benusa
- Department of Anatomy and Neurobiology, Virginia Commonwealth University, Richmond, VA 23298, USA
| | - Audrey D Lafrenaye
- Department of Anatomy and Neurobiology, Virginia Commonwealth University, Richmond, VA 23298, USA
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14
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Wang CF, Zhao CC, Liu WL, Huang XJ, Deng YF, Jiang JY, Li WP. Depletion of Microglia Attenuates Dendritic Spine Loss and Neuronal Apoptosis in the Acute Stage of Moderate Traumatic Brain Injury in Mice. J Neurotrauma 2019; 37:43-54. [PMID: 31397209 DOI: 10.1089/neu.2019.6460] [Citation(s) in RCA: 30] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
Microglia are the primary immune cells in the central nervous system and undergo significant morphological and transcriptional changes after traumatic brain injury (TBI). However, their exact contribution to the pathogenesis of TBI is still debated and remains to be elucidated. In the present study, thy-1 GFP mice received a colony-stimulating factor 1 receptor inhibitor (PLX3397) for 21 consecutive days, then were subjected to moderate fluid percussion injury (FPI). Brain samples were collected at 1 day and 3 days after FPI for flow cytometry analysis, immunofluorescence, dendrite spine quantification, terminal deoxynucleotidyl transferase dUTP nick end labeling assay, and Western blot. We found that PLX3397 treatment significantly attenuated the percentages of resident microglia and infiltrated immune cells. Depletion of microglia promoted neurite outgrowth, preserved dendritic spines and reduced total brain cell and neuronal apoptosis after FPI, which was accompanied by decreased the protein levels of endoplasmic reticulum stress marker proteins, C/EBP-homologous protein and inositol-requiring kinase 1α. Taken together, these findings suggest that microglial depletion may exert beneficial effects in the acute stage of FPI.
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Affiliation(s)
- Chuan-Fang Wang
- Brain Center, Shenzhen Key Laboratory of Neurosurgery, The First Affiliated Hospital of Shenzhen University, Second People's Hospital, Shenzhen, Guangdong, China
| | - Cheng-Cheng Zhao
- Department of Neurosurgery, Sun Yat-sen Memorial Hospital, Sun Yat-sen University, Guangzhou, Guangdong, China
| | - Wen-Lan Liu
- Brain Center, Shenzhen Key Laboratory of Neurosurgery, The First Affiliated Hospital of Shenzhen University, Second People's Hospital, Shenzhen, Guangdong, China
| | - Xian-Jian Huang
- Brain Center, Shenzhen Key Laboratory of Neurosurgery, The First Affiliated Hospital of Shenzhen University, Second People's Hospital, Shenzhen, Guangdong, China
| | - Yue-Fei Deng
- Department of Neurosurgery, Sun Yat-sen Memorial Hospital, Sun Yat-sen University, Guangzhou, Guangdong, China
| | - Ji-Yao Jiang
- Department of Neurosurgery, Ren Ji Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai, China
| | - Wei-Ping Li
- Brain Center, Shenzhen Key Laboratory of Neurosurgery, The First Affiliated Hospital of Shenzhen University, Second People's Hospital, Shenzhen, Guangdong, China
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15
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Bosiacki M, Gąssowska-Dobrowolska M, Kojder K, Fabiańska M, Jeżewski D, Gutowska I, Lubkowska A. Perineuronal Nets and Their Role in Synaptic Homeostasis. Int J Mol Sci 2019; 20:ijms20174108. [PMID: 31443560 PMCID: PMC6747153 DOI: 10.3390/ijms20174108] [Citation(s) in RCA: 47] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2019] [Revised: 08/15/2019] [Accepted: 08/16/2019] [Indexed: 12/17/2022] Open
Abstract
Extracellular matrix (ECM) molecules that are released by neurons and glial cells form perineuronal nets (PNNs) and modulate many neuronal and glial functions. PNNs, whose structure is still not known in detail, surround cell bodies and dendrites, which leaves free space for synapses to come into contact. A reduction in the expression of many neuronal ECM components adversely affects processes that are associated with synaptic plasticity, learning, and memory. At the same time, increased ECM activity, e.g., as a result of astrogliosis following brain damage or in neuroinflammation, can also have harmful consequences. The therapeutic use of enzymes to attenuate elevated neuronal ECM expression after injury or in Alzheimer’s disease has proven to be beneficial by promoting axon growth and increasing synaptic plasticity. Yet, severe impairment of ECM function can also lead to neurodegeneration. Thus, it appears that to ensure healthy neuronal function a delicate balance of ECM components must be maintained. In this paper we review the structure of PNNs and their components, such as hyaluronan, proteoglycans, core proteins, chondroitin sulphate proteoglycans, tenascins, and Hapln proteins. We also characterize the role of ECM in the functioning of the blood-brain barrier, neuronal communication, as well as the participation of PNNs in synaptic plasticity and some clinical aspects of perineuronal net impairment. Furthermore, we discuss the participation of PNNs in brain signaling. Understanding the molecular foundations of the ways that PNNs participate in brain signaling and synaptic plasticity, as well as how they change in physiological and pathological conditions, may help in the development of new therapies for many degenerative and inflammatory diseases of the brain.
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Affiliation(s)
- Mateusz Bosiacki
- Department of Functional Diagnostics and Physical Medicine, Pomeranian Medical University in Szczecin, Żołnierska 54 Str., 71-210 Szczecin, Poland
| | - Magdalena Gąssowska-Dobrowolska
- Department of Cellular Signalling, Mossakowski Medical Research Centre, Polish Academy of Sciences, Pawińskiego 5 Str., 02-106 Warsaw, Poland
| | - Klaudyna Kojder
- Department of Anaesthesiology and Intensive Care, Pomeranian Medical University in Szczecin, 71-252 Szczecin, Poland
| | - Marta Fabiańska
- Institute of Philosophy, University of Szczecin, Krakowska 71-79 Str., 71-017 Szczecin, Poland
| | - Dariusz Jeżewski
- Department of Neurosurgery and Pediatric Neurosurgery, Department of Applied Neurocognitivistics, Pomeranian Medical University in Szczecin, 71-252 Szczecin, Poland
| | - Izabela Gutowska
- Department of Human Nutrition and Metabolomics, Department of Medical Chemistry, Pomeranian Medical University in Szczecin, Broniewskiego 24 Str., 71-252 Szczecin, Poland
| | - Anna Lubkowska
- Department of Functional Diagnostics and Physical Medicine, Pomeranian Medical University in Szczecin, Żołnierska 54 Str., 71-210 Szczecin, Poland.
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16
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Lipachev N, Arnst N, Melnikova A, Jäälinoja H, Kochneva A, Zhigalov A, Kulesskaya N, Aganov AV, Mavlikeev M, Rauvala H, Kiyasov AP, Paveliev M. Quantitative changes in perineuronal nets in development and posttraumatic condition. J Mol Histol 2019; 50:203-216. [PMID: 30903543 DOI: 10.1007/s10735-019-09818-y] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2018] [Accepted: 03/11/2019] [Indexed: 11/30/2022]
Abstract
Perineuronal net (PNN) is a highly structured portion of the CNS extracellular matrix (ECM) regulating synaptic plasticity and a range of pathologic conditions including posttraumatic regeneration and epilepsy. Here we studied Wisteria floribunda agglutinin-stained histological sections to quantify the PNN size and enrichment of chondroitin sulfates in mouse brain and spinal cord. Somatosensory cortex sections were examined during the period of PNN establishment at postnatal days 14, 21 and 28. The single cell PNN size and the chondroitin sulfate intensity were quantified for all cortex layers and specifically for the cortical layer IV which has the highest density of PNN-positive neurons. We demonstrate that the chondroitin sulfate proteoglycan staining intensity is increased between P14 and P28 while the PNN size remains unchanged. We then addressed posttraumatic changes of the PNN expression in laminae 6 and 7 of cervical spinal cord following hemisection injury. We demonstrate increase of the chondroitin sulfate content at 1.6-1.8 mm rostrally from the injury site and increase of the density of PNN-bearing cells at 0.4-1.2 mm caudally from the injury site. We further demonstrate decrease of the single cell PNN area at 0.2 mm caudally from the injury site suggesting that the PNN ECM takes part in the posttraumatic tissue rearrangement in the spinal cord. Our results demonstrate new insights on the PNN structure dynamics in the developing and posttraumatic CNS.
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Affiliation(s)
- Nikita Lipachev
- Neuroscience Center, University of Helsinki, Viikinkaari 4, P.O.Box 56, 00790, Helsinki, Finland.,Institute of Physics, Kazan Federal University, Kazan Kremlyovskaya 16a, Tatarstan, Russia, 420111
| | - Nikita Arnst
- Neuroscience Center, University of Helsinki, Viikinkaari 4, P.O.Box 56, 00790, Helsinki, Finland.,Institut für Biochemie und Biophysik, Friedrich-Schiller-Universität Jena, Hans-Knöll-Str.2, 07745, Jena, Germany
| | - Anastasiia Melnikova
- Neuroscience Center, University of Helsinki, Viikinkaari 4, P.O.Box 56, 00790, Helsinki, Finland.,Institute of Fundamental Medicine and Biology, Kazan Federal University, Kazan K.Marx 74, Tatarstan, Russia, 420012
| | - Harri Jäälinoja
- Institute of Biotechnology, University of Helsinki, Viikinkaari 9, P.O.Box 56, 00790, Helsinki, Finland
| | - Anastasiya Kochneva
- Institute of Fundamental Medicine and Biology, Kazan Federal University, Kazan K.Marx 74, Tatarstan, Russia, 420012
| | - Alexander Zhigalov
- Neuroscience Center, University of Helsinki, Viikinkaari 4, P.O.Box 56, 00790, Helsinki, Finland
| | - Natalia Kulesskaya
- Neuroscience Center, University of Helsinki, Viikinkaari 4, P.O.Box 56, 00790, Helsinki, Finland
| | - Albert V Aganov
- Institute of Physics, Kazan Federal University, Kazan Kremlyovskaya 16a, Tatarstan, Russia, 420111
| | - Mikhail Mavlikeev
- Institute of Fundamental Medicine and Biology, Kazan Federal University, Kazan K.Marx 74, Tatarstan, Russia, 420012
| | - Heikki Rauvala
- Neuroscience Center, University of Helsinki, Viikinkaari 4, P.O.Box 56, 00790, Helsinki, Finland
| | - Andrey P Kiyasov
- Institute of Fundamental Medicine and Biology, Kazan Federal University, Kazan K.Marx 74, Tatarstan, Russia, 420012
| | - Mikhail Paveliev
- Neuroscience Center, University of Helsinki, Viikinkaari 4, P.O.Box 56, 00790, Helsinki, Finland. .,Danish Research Institute of Translational Neuroscience, Aarhus University, Ole Worms Allé 3, 8000, Aarhus C, Denmark.
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17
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Wen TH, Binder DK, Ethell IM, Razak KA. The Perineuronal 'Safety' Net? Perineuronal Net Abnormalities in Neurological Disorders. Front Mol Neurosci 2018; 11:270. [PMID: 30123106 PMCID: PMC6085424 DOI: 10.3389/fnmol.2018.00270] [Citation(s) in RCA: 105] [Impact Index Per Article: 17.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2018] [Accepted: 07/17/2018] [Indexed: 12/22/2022] Open
Abstract
Perineuronal nets (PNN) are extracellular matrix (ECM) assemblies that preferentially ensheath parvalbumin (PV) expressing interneurons. Converging evidence indicates that PV cells and PNN are impaired in a variety of neurological disorders. PNN development and maintenance is necessary for a number of processes within the CNS, including regulation of GABAergic cell function, protection of neurons from oxidative stress, and closure of developmental critical period plasticity windows. Understanding PNN functions may be essential for characterizing the mechanisms of altered cortical excitability observed in neurodegenerative and neurodevelopmental disorders. Indeed, PNN abnormalities have been observed in post-mortem brain tissues of patients with schizophrenia and Alzheimer’s disease. There is impaired development of PNNs and enhanced activity of its key regulator matrix metalloproteinase-9 (MMP-9) in Fragile X Syndrome, a common genetic cause of autism. MMP-9, a protease that cleaves ECM, is differentially regulated in a number of these disorders. Despite this, few studies have addressed the interactions between PNN expression, MMP-9 activity and neuronal excitability. In this review, we highlight the current evidence for PNN abnormalities in CNS disorders associated with altered network function and MMP-9 levels, emphasizing the need for future work targeting PNNs in pathophysiology and therapeutic treatment of neurological disorders.
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Affiliation(s)
- Teresa H Wen
- Neuroscience Graduate Program, University of California, Riverside, Riverside, CA, United States
| | - Devin K Binder
- Neuroscience Graduate Program, University of California, Riverside, Riverside, CA, United States.,Division of Biomedical Sciences, School of Medicine, University of California, Riverside, Riverside, CA, United States
| | - Iryna M Ethell
- Neuroscience Graduate Program, University of California, Riverside, Riverside, CA, United States.,Division of Biomedical Sciences, School of Medicine, University of California, Riverside, Riverside, CA, United States
| | - Khaleel A Razak
- Neuroscience Graduate Program, University of California, Riverside, Riverside, CA, United States.,Psychology Graduate Program, Department of Psychology, University of California, Riverside, Riverside, CA, United States
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18
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Hill RL, Kulbe JR, Singh IN, Wang JA, Hall ED. Synaptic Mitochondria are More Susceptible to Traumatic Brain Injury-induced Oxidative Damage and Respiratory Dysfunction than Non-synaptic Mitochondria. Neuroscience 2018; 386:265-283. [PMID: 29960045 DOI: 10.1016/j.neuroscience.2018.06.028] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2017] [Revised: 06/12/2018] [Accepted: 06/18/2018] [Indexed: 12/17/2022]
Abstract
Traumatic brain injury (TBI) results in mitochondrial dysfunction and induction of lipid peroxidation (LP). Lipid peroxidation-derived neurotoxic aldehydes such as 4-HNE and acrolein bind to mitochondrial proteins, inducing additional oxidative damage and further exacerbating mitochondrial dysfunction and LP. Mitochondria are heterogeneous, consisting of both synaptic and non-synaptic populations. Synaptic mitochondria are reported to be more vulnerable to injury; however, this is the first study to characterize the temporal profile of synaptic and non-synaptic mitochondria following TBI, including investigation of respiratory dysfunction and oxidative damage to mitochondrial proteins between 3 and 120 h following injury. These results indicate that synaptic mitochondria are indeed the more vulnerable population, showing both more rapid and severe impairments than non-synaptic mitochondria. By 24 h, synaptic respiration is significantly impaired compared to synaptic sham, whereas non-synaptic respiration does not decline significantly until 48 h. Decreases in respiration are associated with increases in oxidative damage to synaptic and non-synaptic mitochondrial proteins at 48 h and 72 h, respectively. These results indicate that the therapeutic window for mitochondria-targeted pharmacological neuroprotectants to prevent respiratory dysfunction is shorter for the more vulnerable synaptic mitochondria than for the non-synaptic population.
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Affiliation(s)
- Rachel L Hill
- Spinal Cord and Brain Injury Research Center (SCoBIRC), University of Kentucky College of Medicine, 741 S. Limestone St, Lexington, KY 40536-0509, United States
| | - Jacqueline R Kulbe
- Spinal Cord and Brain Injury Research Center (SCoBIRC), University of Kentucky College of Medicine, 741 S. Limestone St, Lexington, KY 40536-0509, United States; Department of Neuroscience, University of Kentucky College of Medicine, 741 S. Limestone St, Lexington, KY 40536-0509, United States
| | - Indrapal N Singh
- Spinal Cord and Brain Injury Research Center (SCoBIRC), University of Kentucky College of Medicine, 741 S. Limestone St, Lexington, KY 40536-0509, United States; Department of Neuroscience, University of Kentucky College of Medicine, 741 S. Limestone St, Lexington, KY 40536-0509, United States
| | - Juan A Wang
- Spinal Cord and Brain Injury Research Center (SCoBIRC), University of Kentucky College of Medicine, 741 S. Limestone St, Lexington, KY 40536-0509, United States
| | - Edward D Hall
- Spinal Cord and Brain Injury Research Center (SCoBIRC), University of Kentucky College of Medicine, 741 S. Limestone St, Lexington, KY 40536-0509, United States; Department of Neuroscience, University of Kentucky College of Medicine, 741 S. Limestone St, Lexington, KY 40536-0509, United States.
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19
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Proteolytic Remodeling of Perineuronal Nets: Effects on Synaptic Plasticity and Neuronal Population Dynamics. Neural Plast 2018. [PMID: 29531525 PMCID: PMC5817213 DOI: 10.1155/2018/5735789] [Citation(s) in RCA: 37] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
The perineuronal net (PNN) represents a lattice-like structure that is prominently expressed along the soma and proximal dendrites of parvalbumin- (PV-) positive interneurons in varied brain regions including the cortex and hippocampus. It is thus apposed to sites at which PV neurons receive synaptic input. Emerging evidence suggests that changes in PNN integrity may affect glutamatergic input to PV interneurons, a population that is critical for the expression of synchronous neuronal population discharges that occur with gamma oscillations and sharp-wave ripples. The present review is focused on the composition of PNNs, posttranslation modulation of PNN components by sulfation and proteolysis, PNN alterations in disease, and potential effects of PNN remodeling on neuronal plasticity at the single-cell and population level.
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20
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Hylin MJ, Holden RC, Smith AC, Logsdon AF, Qaiser R, Lucke-Wold BP. Juvenile Traumatic Brain Injury Results in Cognitive Deficits Associated with Impaired Endoplasmic Reticulum Stress and Early Tauopathy. Dev Neurosci 2018; 40:175-188. [PMID: 29788004 PMCID: PMC6376969 DOI: 10.1159/000488343] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2017] [Accepted: 03/12/2018] [Indexed: 02/05/2023] Open
Abstract
The leading cause of death in the juvenile population is trauma, and in particular neurotrauma. The juvenile brain response to neurotrauma is not completely understood. Endoplasmic reticulum (ER) stress has been shown to contribute to injury expansion and behavioral deficits in adult rodents and furthermore has been seen in adult postmortem human brains diagnosed with chronic traumatic encephalopathy. Whether endoplasmic reticulum stress is increased in juveniles with traumatic brain injury (TBI) is poorly delineated. We investigated this important topic using a juvenile rat controlled cortical impact (CCI) model. We proposed that ER stress would be significantly increased in juvenile rats following TBI and that this would correlate with behavioral deficits using a juvenile rat model. A juvenile rat (postnatal day 28) CCI model was used. Binding immunoglobulin protein (BiP) and C/EBP homologous protein (CHOP) were measured at 4 h in the ipsilateral pericontusion cortex. Hypoxia-inducible factor (HIF)-1α was measured at 48 h and tau kinase measured at 1 week and 30 days. At 4 h following injury, BiP and CHOP (markers of ER stress) were significantly elevated in rats exposed to TBI. We also found that HIF-1α was significantly upregulated 48 h following TBI showing delayed hypoxia. The early ER stress activation was additionally asso-ciated with the activation of a known tau kinase, glycogen synthase kinase-3β (GSK-3β), by 1 week. Tau oligomers measured by R23 were significantly increased by 30 days following TBI. The biochemical changes following TBI were associated with increased impulsive-like or anti-anxiety behavior measured with the elevated plus maze, deficits in short-term memory measured with novel object recognition, and deficits in spatial memory measured with the Morris water maze in juvenile rats exposed to TBI. These results show that ER stress was increased early in juvenile rats exposed to TBI, that these rats developed tau oligomers over the course of 30 days, and that they had significant short-term and spatial memory deficits following injury.
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Affiliation(s)
- Michael J. Hylin
- Neurotrauma and Rehabilitation Laboratory, Department of Psychology, Southern Illinois University, Carbondale, IL, USA
| | - Ryan C. Holden
- Neurotrauma and Rehabilitation Laboratory, Department of Psychology, Southern Illinois University, Carbondale, IL, USA
| | - Aidan C. Smith
- Neurotrauma and Rehabilitation Laboratory, Department of Psychology, Southern Illinois University, Carbondale, IL, USA
| | - Aric F. Logsdon
- Division of Gerontology and Geriatric Medicine, Department of Medicine, University of Washington School of Medicine, Seattle, WA, USA
| | - Rabia Qaiser
- Department of Neurosurgery, West Virginia University School of Medicine, Morgantown, WV, USA
| | - Brandon P. Lucke-Wold
- Department of Neurosurgery, West Virginia University School of Medicine, Morgantown, WV, USA
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21
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Wang CF, Zhao CC, Weng WJ, Lei J, Lin Y, Mao Q, Gao GY, Feng JF, Jiang JY. Alteration in Long Non-Coding RNA Expression after Traumatic Brain Injury in Rats. J Neurotrauma 2017; 34:2100-2108. [PMID: 28145813 DOI: 10.1089/neu.2016.4642] [Citation(s) in RCA: 37] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Affiliation(s)
- Chuan-fang Wang
- Department of Neurosurgery, Ren Ji Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai, People's Republic of China
- Shanghai Institute of Head Trauma, Shanghai, People's Republic of China
| | - Cheng-cheng Zhao
- Department of Neurosurgery, Ren Ji Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai, People's Republic of China
- Shanghai Institute of Head Trauma, Shanghai, People's Republic of China
| | - Wei-ji Weng
- Department of Neurosurgery, Ren Ji Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai, People's Republic of China
| | - Jin Lei
- Department of Neurosurgery, Ren Ji Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai, People's Republic of China
| | - Yong Lin
- Department of Neurosurgery, Ren Ji Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai, People's Republic of China
- Shanghai Institute of Head Trauma, Shanghai, People's Republic of China
| | - Qing Mao
- Department of Neurosurgery, Ren Ji Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai, People's Republic of China
| | - Guo-yi Gao
- Department of Neurosurgery, Ren Ji Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai, People's Republic of China
- Shanghai Institute of Head Trauma, Shanghai, People's Republic of China
| | - Jun-feng Feng
- Department of Neurosurgery, Ren Ji Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai, People's Republic of China
- Shanghai Institute of Head Trauma, Shanghai, People's Republic of China
| | - Ji-yao Jiang
- Department of Neurosurgery, Ren Ji Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai, People's Republic of China
- Shanghai Institute of Head Trauma, Shanghai, People's Republic of China
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22
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Hylin MJ, Kerr AL, Holden R. Understanding the Mechanisms of Recovery and/or Compensation following Injury. Neural Plast 2017; 2017:7125057. [PMID: 28512585 PMCID: PMC5415868 DOI: 10.1155/2017/7125057] [Citation(s) in RCA: 50] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2016] [Revised: 02/24/2017] [Accepted: 03/26/2017] [Indexed: 11/30/2022] Open
Abstract
Injury due to stroke and traumatic brain injury result in significant long-term effects upon behavioral functioning. One central question to rehabilitation research is whether the nature of behavioral improvement observed is due to recovery or the development of compensatory mechanisms. The nature of functional improvement can be viewed from the perspective of behavioral changes or changes in neuroanatomical plasticity that follows. Research suggests that these changes correspond to each other in a bidirectional manner. Mechanisms surrounding phenomena like neural plasticity may offer an opportunity to explain how variables such as experience can impact improvement and influence the definition of recovery. What is more, the intensity of the rehabilitative experiences may influence the ability to recover function and support functional improvement of behavior. All of this impacts how researchers, clinicians, and medical professionals utilize rehabilitation.
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Affiliation(s)
- Michael J. Hylin
- Neurotrauma and Rehabilitation Laboratory, Department of Psychology, Southern Illinois University, Carbondale, IL, USA
| | - Abigail L. Kerr
- Department of Psychology, Illinois Wesleyan University, Bloomington, IL, USA
| | - Ryan Holden
- Neurotrauma and Rehabilitation Laboratory, Department of Psychology, Southern Illinois University, Carbondale, IL, USA
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23
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Zhao CC, Wang CF, Li WP, Lin Y, Tang QL, Feng JF, Mao Q, Gao GY, Jiang JY. Mild Hypothermia Promotes Pericontusion Neuronal Sprouting via Suppressing Suppressor of Cytokine Signaling 3 Expression after Moderate Traumatic Brain Injury. J Neurotrauma 2017; 34:1636-1644. [PMID: 27923323 DOI: 10.1089/neu.2016.4759] [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] [Indexed: 12/22/2022] Open
Abstract
Mild therapeutic hypothermia is a candidate for the treatment of traumatic brain injury (TBI). However, the role of mild hypothermia in neuronal sprouting after TBI remains obscure. We used a fluid percussion injury (FPI) model to assess the effect of mild hypothermia on pericontusion neuronal sprouting after TBI in rats. Male Sprague-Dawley rats underwent FPI or sham surgery, followed by mild hypothermia treatment (33°C) or normothermia treatment (37°C) for 3 h. All the rats were euthanized at 7 days after FPI. Neuronal sprouting that was confirmed by an increase in growth associated protein-43 (GAP-43) expression was evaluated using immunofluorescence and Western blot assays. The expression levels of several intrinsic and extrinsic sprouting-associated genes such as neurite outgrowth inhibitor A (NogoA), phosphatase and tensin homolog (PTEN), and suppressor of cytokine signaling 3 (SOCS3) were analyzed by quantitative real-time polymerase chain reaction (RT-PCR). Our results revealed that mild hypothermia significantly increased the expression level of GAP-43 and dramatically suppressed the expression level of interleukin-6 (IL-6) and SOCS3 at 7 days after FPI in the ipsilateral cortex compared with that of the normothermia TBI group. These data suggest that post-traumatic mild hypothermia promotes pericontusion neuronal sprouting after TBI. Moreover, the mechanism of hypothermia-induced neuronal sprouting might be partially associated with decreased levels of SOCS3.
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Affiliation(s)
- Cheng-Cheng Zhao
- 1 Department of Neurosurgery, Ren Ji Hospital, School of Medicine, Shanghai Jiao Tong University , Shanghai Institute of Head Trauma, Shanghai, People's Republic of China
| | - Chuan-Fang Wang
- 1 Department of Neurosurgery, Ren Ji Hospital, School of Medicine, Shanghai Jiao Tong University , Shanghai Institute of Head Trauma, Shanghai, People's Republic of China
| | - Wei-Ping Li
- 2 Department of Neurosurgery, Shenzhen Second People's Hospital, Shenzhen University , Shenzhen, Guangdong, People's Republic of China
| | - Yong Lin
- 1 Department of Neurosurgery, Ren Ji Hospital, School of Medicine, Shanghai Jiao Tong University , Shanghai Institute of Head Trauma, Shanghai, People's Republic of China
| | - Qi-Lin Tang
- 1 Department of Neurosurgery, Ren Ji Hospital, School of Medicine, Shanghai Jiao Tong University , Shanghai Institute of Head Trauma, Shanghai, People's Republic of China
| | - Jun-Feng Feng
- 1 Department of Neurosurgery, Ren Ji Hospital, School of Medicine, Shanghai Jiao Tong University , Shanghai Institute of Head Trauma, Shanghai, People's Republic of China
| | - Qing Mao
- 1 Department of Neurosurgery, Ren Ji Hospital, School of Medicine, Shanghai Jiao Tong University , Shanghai Institute of Head Trauma, Shanghai, People's Republic of China
| | - Guo-Yi Gao
- 1 Department of Neurosurgery, Ren Ji Hospital, School of Medicine, Shanghai Jiao Tong University , Shanghai Institute of Head Trauma, Shanghai, People's Republic of China
| | - Ji-Yao Jiang
- 1 Department of Neurosurgery, Ren Ji Hospital, School of Medicine, Shanghai Jiao Tong University , Shanghai Institute of Head Trauma, Shanghai, People's Republic of China
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Donegan JJ, Lodge DJ. Hippocampal Perineuronal Nets Are Required for the Sustained Antidepressant Effect of Ketamine. Int J Neuropsychopharmacol 2016; 20:354-358. [PMID: 27806991 PMCID: PMC5578802 DOI: 10.1093/ijnp/pyw095] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/25/2016] [Accepted: 10/31/2016] [Indexed: 12/01/2022] Open
Abstract
BACKGROUND N-methyl-D-aspartate receptor antagonists, like ketamine, produce a rapid-acting and long-lasting antidepressant effect. Although the mechanism is not completely understood, ketamine is thought to preferentially target N-methyl-D-aspartate receptors on fast-spiking parvalbumin-containing interneurons. The function of parvalbumin-containing interneurons is dependent on perineuronal nets, a specialized form of extracellular matrix that surrounds these cells. METHODS Chondroitinase was used to enzymatically degrade perineuronal nets surrounding parvalbumin-containing interneurons in the ventral hippocampus, a region that is involved in the antidepressant response to ketamine. Rats were tested on the forced swim test 30 minutes and 1 week after ketamine administration. RESULTS Thirty minutes after ketamine injection, both chondroitinase-treated and control animals had a decrease in immobility. One week later, however, the antidepressant-like response observed with ketamine was completely abolished in the chondroitinase-treated animals. CONCLUSION This suggests that parvalbumin interneuron function in the ventral hippocampus is essential for the sustained antidepressant effect of ketamine.
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Affiliation(s)
- Jennifer J Donegan
- Department of Pharmacology and Center for Biomedical Neuroscience, University of Texas Health Science Center, San Antonio, Texas.,Correspondence: Jennifer Donegan, PhD, University of Texas Health Science Center at San Antonio, Department of Pharmacology, Mail Code 7764, 7703 Floyd Curl Drive, San Antonio, TX 78229 ()
| | - Daniel J Lodge
- Department of Pharmacology and Center for Biomedical Neuroscience, University of Texas Health Science Center, San Antonio, Texas
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Sainath R, Ketschek A, Grandi L, Gallo G. CSPGs inhibit axon branching by impairing mitochondria-dependent regulation of actin dynamics and axonal translation. Dev Neurobiol 2016; 77:454-473. [PMID: 27429169 DOI: 10.1002/dneu.22420] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2016] [Revised: 06/28/2016] [Accepted: 07/14/2016] [Indexed: 12/27/2022]
Abstract
Chondroitin sulfate proteoglycans (CSPGs) inhibit the formation of axon collateral branches. The regulation of the axonal cytoskeleton and mitochondria are important components of the mechanism of branching. Actin-dependent axonal plasticity, reflected in the dynamics of axonal actin patches and filopodia, is greatest along segments of the axon populated by mitochondria. It is reported that CSPGs partially depolarize the membrane potential of axonal mitochondria, which impairs the dynamics of the axonal actin cytoskeleton and decreases the formation and duration of axonal filopodia, the first steps in the mechanism of branching. The effects of CSPGs on actin cytoskeletal dynamics are specific to axon segments populated by mitochondria. In contrast, CSPGs do not affect the microtubule content of axons, or the localization of microtubules into axonal filopodia, a required step in the mechanism of branch formation. It is also reported that CSPGs decrease the mitochondria-dependent axonal translation of cortactin, an actin associated protein involved in branching. Finally, the inhibitory effects of CSPGs on axon branching, actin cytoskeletal dynamics and the axonal translation of cortactin are reversed by culturing neurons with acetyl-l-carnitine, which promotes mitochondrial respiration. Collectively these data indicate that CSPGs impair mitochondrial function in axons, an effect which contributes to the inhibition of axon branching. © 2016 Wiley Periodicals, Inc. Develop Neurobiol 77: 419-437, 2017.
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Affiliation(s)
- Rajiv Sainath
- Temple University School of Medicine, Department of Anatomy and Cell Biology, Shriners Hospitals Pediatric Research Center, 3500 N Broad St, Philadelphia, Pennsylvania
| | - Andrea Ketschek
- Temple University School of Medicine, Department of Anatomy and Cell Biology, Shriners Hospitals Pediatric Research Center, 3500 N Broad St, Philadelphia, Pennsylvania
| | - Leah Grandi
- Temple University School of Medicine, Department of Anatomy and Cell Biology, Shriners Hospitals Pediatric Research Center, 3500 N Broad St, Philadelphia, Pennsylvania
| | - Gianluca Gallo
- Temple University School of Medicine, Department of Anatomy and Cell Biology, Shriners Hospitals Pediatric Research Center, 3500 N Broad St, Philadelphia, Pennsylvania
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26
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Harris NG, Verley DR, Gutman BA, Sutton RL. Bi-directional changes in fractional anisotropy after experiment TBI: Disorganization and reorganization? Neuroimage 2016; 133:129-143. [PMID: 26975556 PMCID: PMC4889542 DOI: 10.1016/j.neuroimage.2016.03.012] [Citation(s) in RCA: 49] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/24/2015] [Revised: 03/02/2016] [Accepted: 03/03/2016] [Indexed: 11/26/2022] Open
Abstract
The current dogma to explain the extent of injury-related changes following rodent controlled cortical impact (CCI) injury is a focal injury with limited axonal pathology. However, there is in fact good, published histologic evidence to suggest that axonal injury is far more widespread in this model than generally thought. One possibility that might help to explain this is the often-used region-of-interest data analysis approach taken by experimental traumatic brain injury (TBI) diffusion tensor imaging (DTI) or histologic studies that might miss more widespread damage, when compared to the whole brain, statistically robust method of tract-based analysis used more routinely in clinical research. To determine the extent of DTI changes in this model, we acquired in vivo DTI data before and at 1 and 4weeks after CCI injury in 17 adult male rats and analyzed parametric maps of fractional anisotropy (FA), axial, radial, and mean diffusivity (AD, RD, MD), tensor mode (MO), and fiber tract density (FTD) using tract-based spatial statistics. Contusion volume was used as a surrogate marker of injury severity and as a covariate for investigating severity dependence of the data. Mean fiber tract length was also computed from seeds in the cortical spinal tract regions. In parallel experiments (n=3-5/group), we investigated corpus callosum neurofilaments and demyelination using immunohistochemistry (IHC) at 3days and 6weeks, callosal tract patency using dual-label retrograde tract tracing at 5weeks, and the contribution of gliosis to DTI parameter maps using GFAP IHC at 4weeks post-injury. The data show widespread ipsilateral regions of significantly reduced FA at 1week post-injury, driven by temporally changing values of AD, RD, and MD that persist to 4weeks. Demyelination, retrograde label tract loss, and reductions in MO (tract degeneration) and FTD were shown to underpin these data. Significant FA increases occurred in subcortical and corticospinal tract regions that were spatially distinct from regions of FA decrease, grossly affected gliotic areas, and MO changes. However, there was good spatial correspondence between regions of increased FA and areas of increased FTD and mean fiber length. We discuss these widespread changes in DTI parameters in terms of axonal degeneration and potential reorganization, with reference to a resting state fMRI companion paper (Harris et al., 2016, Exp. Neurol. 227:124-138) that demonstrated altered functional connectivity data acquired from the same rats used in this study.
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Affiliation(s)
- N G Harris
- UCLA Brain injury Research Center, Department of Neurosurgery, University of California, Los Angeles, Los Angeles, USA.
| | - D R Verley
- UCLA Brain injury Research Center, Department of Neurosurgery, University of California, Los Angeles, Los Angeles, USA
| | - B A Gutman
- Department of Neurology, Imaging Genetics Center, Keck/USC School of Medicine, Institute for Neuroimaging and Informatics, University of Southern California, Los Angeles, CA, USA
| | - R L Sutton
- UCLA Brain injury Research Center, Department of Neurosurgery, University of California, Los Angeles, Los Angeles, USA
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27
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Harris NG, Verley DR, Gutman BA, Thompson PM, Yeh HJ, Brown JA. Disconnection and hyper-connectivity underlie reorganization after TBI: A rodent functional connectomic analysis. Exp Neurol 2016; 277:124-138. [PMID: 26730520 PMCID: PMC4761291 DOI: 10.1016/j.expneurol.2015.12.020] [Citation(s) in RCA: 60] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2015] [Revised: 12/01/2015] [Accepted: 12/22/2015] [Indexed: 10/22/2022]
Abstract
While past neuroimaging methods have contributed greatly to our understanding of brain function after traumatic brain injury (TBI), resting state functional MRI (rsfMRI) connectivity methods have more recently provided a far more unbiased approach with which to monitor brain circuitry compared to task-based approaches. However, current knowledge on the physiologic underpinnings of the correlated blood oxygen level dependent signal, and how changes in functional connectivity relate to reorganizational processes that occur following injury is limited. The degree and extent of this relationship remain to be determined in order that rsfMRI methods can be fully adapted for determining the optimal timing and type of rehabilitative interventions that can be used post-TBI to achieve the best outcome. Very few rsfMRI studies exist after experimental TBI and therefore we chose to acquire rsfMRI data before and at 7, 14 and 28 days after experimental TBI using a well-known, clinically-relevant, unilateral controlled cortical impact injury (CCI) adult rat model of TBI. This model was chosen since it has widespread axonal injury, a well-defined time-course of reorganization including spine, dendrite, axonal and cortical map changes, as well as spontaneous recovery of sensorimotor function by 28 d post-injury from which to interpret alterations in functional connectivity. Data were co-registered to a parcellated rat template to generate adjacency matrices for network analysis by graph theory. Making no assumptions about direction of change, we used two-tailed statistical analysis over multiple brain regions in a data-driven approach to access global and regional changes in network topology in order to assess brain connectivity in an unbiased way. Our main hypothesis was that deficits in functional connectivity would become apparent in regions known to be structurally altered or deficient in axonal connectivity in this model. The data show the loss of functional connectivity predicted by the structural deficits, not only within the primary sensorimotor injury site and pericontused regions, but the normally connected homotopic cortex, as well as subcortical regions, all of which persisted chronically. Especially novel in this study is the unanticipated finding of widespread increases in connection strength that dwarf both the degree and extent of the functional disconnections, and which persist chronically in some sensorimotor and subcortically connected regions. Exploratory global network analysis showed changes in network parameters indicative of possible acutely increased random connectivity and temporary reductions in modularity that were matched by local increases in connectedness and increased efficiency among more weakly connected regions. The global network parameters: shortest path-length, clustering coefficient and modularity that were most affected by trauma also scaled with the severity of injury, so that the corresponding regional measures were correlated to the injury severity most notably at 7 and 14 days and especially within, but not limited to, the contralateral cortex. These changes in functional network parameters are discussed in relation to the known time-course of physiologic and anatomic data that underlie structural and functional reorganization in this experiment model of TBI.
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Affiliation(s)
- N G Harris
- UCLA Brain Research Center, Department of Neurosurgery, University of California, Los Angeles, USA.
| | - D R Verley
- UCLA Brain Research Center, Department of Neurosurgery, University of California, Los Angeles, USA
| | - B A Gutman
- Imaging Genetics Center, Institute for Neuroimaging and Informatics, Department of Neurology, Keck/USC School of Medicine, University of Southern California, Los Angeles, CA, USA
| | - P M Thompson
- Departments of Psychiatry, Engineering, Radiology, & Ophthalmology, Keck/USC School of Medicine, University of Southern California, Los Angeles, CA, USA
| | - H J Yeh
- Department of Neurology, University of California, Los Angeles, USA
| | - J A Brown
- Department of Neurology, University of California at San Francisco School of Medicine, San Francisco, CA, USA
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Widerström-Noga E, Govind V, Adcock JP, Levin BE, Maudsley AA. Subacute Pain after Traumatic Brain Injury Is Associated with Lower Insular N-Acetylaspartate Concentrations. J Neurotrauma 2016; 33:1380-9. [PMID: 26486760 DOI: 10.1089/neu.2015.4098] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023] Open
Abstract
Persistent pain is experienced by more than 50% of persons who sustain a traumatic brain injury (TBI), and more than 30% experience significant pain as early as 6 weeks after injury. Although neuropathic pain is a common consequence after CNS injuries, little attention has been given to neuropathic pain symptoms after TBI. Magnetic resonance spectroscopy (MRS) studies in subjects with TBI show decreased brain concentrations of N-acetylaspartate (NAA), a marker of neuronal density and viability. Although decreased brain NAA has been associated with neuropathic pain associated with spinal cord injury (SCI) and diabetes, this relationship has not been examined after TBI. The primary purpose of this study was to test the hypothesis that lower NAA concentrations in brain areas involved in pain perception and modulation would be associated with greater severity of neuropathic pain symptoms. Participants with TBI underwent volumetric MRS, pain and psychosocial interviews. Cluster analysis of the Neuropathic Pain Symptom Inventory subscores resulted in two TBI subgroups: The Moderate Neuropathic Pain (n = 17; 37.8%), with significantly (p = 0.038) lower insular NAA than the Low or no Neuropathic Pain group (n = 28; 62.2%), or age- and sex-matched controls (n = 45; p < 0.001). A hierarchical linear regression analysis controlling for age, sex, and time post-TBI showed that pain severity was significantly (F = 11.0; p < 0.001) predicted by a combination of lower insular NAA/Creatine (p < 0.001), lower right insular gray matter fractional volume (p < 0.001), female sex (p = 0.005), and older age (p = 0.039). These findings suggest that neuronal dysfunction in brain areas involved in pain processing is associated with pain after TBI.
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Affiliation(s)
- Eva Widerström-Noga
- 1 The Miami Project to Cure Paralysis, University of Miami Miller School of Medicine , Miami, Florida.,2 Department of Neurological Surgery, University of Miami Miller School of Medicine , Miami, Florida.,3 Department of Physical Medicine and Rehabilitation, University of Miami Miller School of Medicine , Miami, Florida
| | - Varan Govind
- 4 Department of Radiology, University of Miami Miller School of Medicine , Miami, Florida
| | - James P Adcock
- 1 The Miami Project to Cure Paralysis, University of Miami Miller School of Medicine , Miami, Florida
| | - Bonnie E Levin
- 5 Department of Neurology, University of Miami Miller School of Medicine , Miami, Florida
| | - Andrew A Maudsley
- 4 Department of Radiology, University of Miami Miller School of Medicine , Miami, Florida
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Gang L, Yao YC, Liu YF, Li YP, Yang K, Lu L, Cheng YC, Chen XY, Tu Y. Co-culture of oligodendrocytes and neurons can be used to assess drugs for axon regeneration in the central nervous system. Neural Regen Res 2015; 10:1612-6. [PMID: 26692858 PMCID: PMC4660754 DOI: 10.4103/1673-5374.167759] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
We present a novel in vitro model in which to investigate the efficacy of experimental drugs for the promotion of axon regeneration in the central nervous system. We co-cultured rat hippocampal neurons and cerebral cortical oligodendrocytes, and tested the co-culture system using a Nogo-66 receptor antagonist peptide (NEP1–40), which promotes axonal growth. Primary cultured oligodendrocytes suppressed axonal growth in the rat hippocampus, but NEP1–40 stimulated axonal growth in the co-culture system. Our results confirm the validity of the neuron-oligodendrocyte co-culture system as an assay for the evaluation of drugs for axon regeneration in the central nervous system.
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Affiliation(s)
- Lin Gang
- Neurological Hospital of Affiliated Hospital of Logistics University of Chinese People's Armed Police Force, Tianjin, China ; Tianjin University of Traditional Chinese Medicine, Tianjin, China
| | - Yu-Chen Yao
- Neurological Hospital of Affiliated Hospital of Logistics University of Chinese People's Armed Police Force, Tianjin, China
| | - Ying-Fu Liu
- Logistics University of Chinese People's Armed Police Forces, Tianjin, China
| | - Yi-Peng Li
- Neurological Hospital of Affiliated Hospital of Logistics University of Chinese People's Armed Police Force, Tianjin, China ; Tianjin University of Traditional Chinese Medicine, Tianjin, China
| | - Kai Yang
- Neurological Hospital of Affiliated Hospital of Logistics University of Chinese People's Armed Police Force, Tianjin, China ; Liaoning Medical University, Jinzhou, Liaoning Province, China
| | - Lei Lu
- Neurological Hospital of Affiliated Hospital of Logistics University of Chinese People's Armed Police Force, Tianjin, China ; Tianjin University of Traditional Chinese Medicine, Tianjin, China
| | - Yuan-Chi Cheng
- Neurological Hospital of Affiliated Hospital of Logistics University of Chinese People's Armed Police Force, Tianjin, China ; Liaoning Medical University, Jinzhou, Liaoning Province, China
| | - Xu-Yi Chen
- Neurological Hospital of Affiliated Hospital of Logistics University of Chinese People's Armed Police Force, Tianjin, China ; Key Laboratory of Nerve Trauma Repair, Tianjin, China
| | - Yue Tu
- Neurological Hospital of Affiliated Hospital of Logistics University of Chinese People's Armed Police Force, Tianjin, China ; Key Laboratory of Nerve Trauma Repair, Tianjin, China
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30
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Temporal pattern of neurodegeneration, programmed cell death, and neuroplastic responses in the thalamus after lateral fluid percussion brain injury in the rat. J Neuropathol Exp Neurol 2015; 74:512-26. [PMID: 25933386 DOI: 10.1097/nen.0000000000000194] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
Abstract
The effects of traumatic brain injury (TBI) on the thalamus are not well characterized. We analyzed neuronal degeneration and loss, apoptosis, programmed cell death-executing pathways, and neuroplastic responses in the rat thalamus during the first week after lateral fluid percussion injury (LFPI). The most prominent neurodegenerative and neuroplastic changes were observed in the region containing the posterior thalamic nuclear group and ventral posteromedial and posterolateral thalamic nuclei ipsilateral to the LFPI. There was progressive neurodegeneration in these regions, with maximal neuronal loss on Day 7. Increases in numbers of apoptotic cells were detected on Day 1 and were enhanced on Days 3 and 7 after TBI. There was unchanged expression of active caspase-3 at all postinjury time points, but there was increased expression of apoptosis-inducing factor (AIF) on Day 7. The AIF nuclear translocation was detected on Day 1 and was maximal on Day 7. Total thalamic synaptophysin expression was unchanged, but immunostaining intensities were increased at all time points after TBI. Decreased growth-associated protein-43 expression and signal intensity were observed on Day 1. Our results suggest that progressive neuronal damage and loss, AIF signaling pathway-dependent programmed cell death, and limited neuroplastic changes occur in the rat thalamus during the first week after LFPI induction.
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31
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Zhang ZC, Luan F, Xie CY, Geng DD, Wang YY, Ma J. Low-frequency transcranial magnetic stimulation is beneficial for enhancing synaptic plasticity in the aging brain. Neural Regen Res 2015. [PMID: 26199608 PMCID: PMC4498353 DOI: 10.4103/1673-5374.158356] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023] Open
Abstract
In the aging brain, cognitive function gradually declines and causes a progressive reduction in the structural and functional plasticity of the hippocampus. Transcranial magnetic stimulation is an emerging and novel neurological and psychiatric tool used to investigate the neurobiology of cognitive function. Recent studies have demonstrated that low-frequency transcranial magnetic stimulation (≤1 Hz) ameliorates synaptic plasticity and spatial cognitive deficits in learning-impaired mice. However, the mechanisms by which this treatment improves these deficits during normal aging are still unknown. Therefore, the current study investigated the effects of transcranial magnetic stimulation on the brain-derived neurotrophic factor signal pathway, synaptic protein markers, and spatial memory behavior in the hippocampus of normal aged mice. The study also investigated the downstream regulator, Fyn kinase, and the downstream effectors, synaptophysin and growth-associated protein 43 (both synaptic markers), to determine the possible mechanisms by which transcranial magnetic stimulation regulates cognitive capacity. Transcranial magnetic stimulation with low intensity (110% average resting motor threshold intensity, 1 Hz) increased mRNA and protein levels of brain-derived neurotrophic factor, tropomyosin receptor kinase B, and Fyn in the hippocampus of aged mice. The treatment also upregulated the mRNA and protein expression of synaptophysin and growth-associated protein 43 in the hippocampus of these mice. In conclusion, brain-derived neurotrophic factor signaling may play an important role in sustaining and regulating structural synaptic plasticity induced by transcranial magnetic stimulation in the hippocampus of aging mice, and Fyn may be critical during this regulation. These responses may change the structural plasticity of the aging hippocampus, thereby improving cognitive function.
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Affiliation(s)
- Zhan-Chi Zhang
- Department of Human Anatomy, Hebei Medical University, Shijiazhuang, Hebei Province, China
| | - Feng Luan
- Department of Otorhinolaryngology, Third Hospital of Hebei Medical University, Shijiazhuang, Hebei Province, China
| | - Chun-Yan Xie
- Second Surgical Department, Qinghe Public Hospital of Hebei Province, Xingtai, Hebei Province, China
| | - Dan-Dan Geng
- Department of Human Anatomy, Hebei Medical University, Shijiazhuang, Hebei Province, China
| | - Yan-Yong Wang
- Department of Neurology, First Hospital of Hebei Medical University, Shijiazhuang, Hebei Province, China ; Hebei Key Laboratory for Brain Aging and Cognitive Neuroscience, Shijiazhuang, Hebei Province, China
| | - Jun Ma
- Department of Human Anatomy, Hebei Medical University, Shijiazhuang, Hebei Province, China ; Hebei Key Laboratory for Brain Aging and Cognitive Neuroscience, Shijiazhuang, Hebei Province, China
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32
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Merlo L, Cimino F, Angileri FF, La Torre D, Conti A, Cardali SM, Saija A, Germanò A. Alteration in synaptic junction proteins following traumatic brain injury. J Neurotrauma 2015; 31:1375-85. [PMID: 24661152 DOI: 10.1089/neu.2014.3385] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Extensive research and scientific efforts have been focused on the elucidation of the pathobiology of cellular and axonal damage following traumatic brain injury (TBI). Conversely, few studies have specifically addressed the issue of synaptic dysfunction. Synaptic junction proteins may be involved in post-TBI alterations, leading to synaptic loss or disrupted plasticity. A Synapse Protein Database on synapse ontology identified 109 domains implicated in synaptic activities and over 5000 proteins, but few of these demonstrated to play a role in the synaptic dysfunction after TBI. These proteins are involved in neuroplasticity and neuromodulation and, most importantly, may be used as novel neuronal markers of TBI for specific intervention.
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Affiliation(s)
- Lucia Merlo
- 1 Department of Neurosciences, University of Messina , Messina, Italy
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Burda JE, Bernstein AM, Sofroniew MV. Astrocyte roles in traumatic brain injury. Exp Neurol 2015; 275 Pt 3:305-315. [PMID: 25828533 DOI: 10.1016/j.expneurol.2015.03.020] [Citation(s) in RCA: 493] [Impact Index Per Article: 54.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2014] [Revised: 02/28/2015] [Accepted: 03/08/2015] [Indexed: 01/15/2023]
Abstract
Astrocytes sense changes in neural activity and extracellular space composition. In response, they exert homeostatic mechanisms critical for maintaining neural circuit function, such as buffering neurotransmitters, modulating extracellular osmolarity and calibrating neurovascular coupling. In addition to upholding normal brain activities, astrocytes respond to diverse forms of brain injury with heterogeneous and progressive changes of gene expression, morphology, proliferative capacity and function that are collectively referred to as reactive astrogliosis. Traumatic brain injury (TBI) sets in motion complex events in which noxious mechanical forces cause tissue damage and disrupt central nervous system (CNS) homeostasis, which in turn trigger diverse multi-cellular responses that evolve over time and can lead either to neural repair or secondary cellular injury. In response to TBI, astrocytes in different cellular microenvironments tune their reactivity to varying degrees of axonal injury, vascular disruption, ischemia and inflammation. Here we review different forms of TBI-induced astrocyte reactivity and the functional consequences of these responses for TBI pathobiology. Evidence regarding astrocyte contribution to post-traumatic tissue repair and synaptic remodeling is examined, and the potential for targeting specific aspects of astrogliosis to ameliorate TBI sequelae is considered.
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Affiliation(s)
- Joshua E Burda
- Department of Neurobiology and Brain Research Institute, University of California Los Angeles, Los Angeles, CA 90095-1763, USA
| | - Alexander M Bernstein
- Department of Neurobiology and Brain Research Institute, University of California Los Angeles, Los Angeles, CA 90095-1763, USA
| | - Michael V Sofroniew
- Department of Neurobiology and Brain Research Institute, University of California Los Angeles, Los Angeles, CA 90095-1763, USA.
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Predicting changes in cortical electrophysiological function after in vitro traumatic brain injury. Biomech Model Mechanobiol 2015; 14:1033-44. [PMID: 25628144 DOI: 10.1007/s10237-015-0652-6] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2014] [Accepted: 01/14/2015] [Indexed: 01/09/2023]
Abstract
Finite element (FE) models of traumatic brain injury (TBI) are capable of predicting injury-induced brain tissue deformation. However, current FE models are not equipped to predict the biological consequences of tissue deformation, which requires the determination of tolerance criteria relating the effects of mechanical stimuli to biologically relevant functional responses. To address this deficiency, we present functional tolerance criteria for the cortex for alterations in neuronal network electrophysiological function in response to controlled mechanical stimuli. Organotypic cortical slice cultures were mechanically injured via equibiaxial stretch with a well-characterized in vitro model of TBI at tissue strains and strain rates relevant to TBI (up to Lagrangian strain of 0.59 and strain rates up to 29 [Formula: see text]. At 4-6 days post-injury, electrophysiological function was assessed simultaneously throughout the cortex using microelectrode arrays. Electrophysiological parameters associated with unstimulated spontaneous network activity (neural event rate, duration, and magnitude), stimulated evoked responses (the maximum response [Formula: see text], the stimulus current necessary for a half-maximal response [Formula: see text], and the electrophysiological parameter [Formula: see text] that is representative of firing uniformity), and evoked paired-pulse ratios at varying interstimulus intervals were quantified for each cortical slice culture. Nonlinear regression was performed between mechanical injury parameters as independent variables (tissue strain and strain rate) and each electrophysiological parameter as output. Parsimonious best-fit equations were determined from a large pool of candidate equations with tenfold cross-validation. Changes in electrophysiological parameters were dependent on strain and strain rate in a complex manner. Compared to the hippocampus, the cortex was less spontaneously active, less excitable, and less prone to significant changes in electrophysiological function in response to controlled deformation (strain or strain rate). Our study provides functional data that can be incorporated into FE models to improve their predictive capabilities of the in vivo consequences of TBI.
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Griesbach GS, Hovda DA. Cellular and molecular neuronal plasticity. HANDBOOK OF CLINICAL NEUROLOGY 2015; 128:681-90. [DOI: 10.1016/b978-0-444-63521-1.00042-x] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
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McGinn MJ, Povlishock JT. Cellular and molecular mechanisms of injury and spontaneous recovery. HANDBOOK OF CLINICAL NEUROLOGY 2015; 127:67-87. [PMID: 25702210 DOI: 10.1016/b978-0-444-52892-6.00005-2] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Until recently, most have assumed that traumatic brain injury (TBI) was singularly associated with the overt destruction of brain tissue resulting in subsequent morbidity or death. More recently, experimental and clinical studies have shown that the pathobiology of TBI is more complex, involving a host of cellular and subcellular changes that impact on neuronal function and viability while also affecting vascular reactivity and the activation of multiple biological response pathways. Here we review the brain's response to injury, examining both focal and diffuse changes and their implications for post-traumatic brain dysfunction and recovery. TBI-induced neuronal dysfunction and death as well as the diffuse involvement of multiple fiber projections are discussed together with considerations of how local axonal membrane changes or channelopathy translate into local ionic dysregulation and axonal disconnection. Concomitant changes in the cerebral microcirculation are also discussed and their relationship with the parallel changes in the brain's metabolism is considered. These cellular and subcellular events occurring within neurons and their blood supply are correlated with multiple biological response modifiers evoked by generalized post-traumatic inflammation and the parallel activation of oxidative stress processes. The chapter closes with considerations of recovery following focal or diffuse injury. Evidence for dynamic brain reorganization/repair is presented, with considerations of traumatically induced circuit disruption and their progression to either adaptive or in some cases, maladaptive reorganization.
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Affiliation(s)
- Melissa J McGinn
- Department of Anatomy and Neurobiology, Medical College of Virginia Campus of Virginia Commonwealth University, Richmond, VA, USA
| | - John T Povlishock
- Department of Anatomy and Neurobiology, Medical College of Virginia Campus of Virginia Commonwealth University, Richmond, VA, USA.
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Repetitive transcranial magnetic stimulation (rTMS) influences spatial cognition and modulates hippocampal structural synaptic plasticity in aging mice. Exp Gerontol 2014; 58:256-68. [DOI: 10.1016/j.exger.2014.08.011] [Citation(s) in RCA: 43] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2014] [Revised: 07/27/2014] [Accepted: 08/26/2014] [Indexed: 01/09/2023]
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Madinier A, Quattromani MJ, Sjölund C, Ruscher K, Wieloch T. Enriched housing enhances recovery of limb placement ability and reduces aggrecan-containing perineuronal nets in the rat somatosensory cortex after experimental stroke. PLoS One 2014; 9:e93121. [PMID: 24664200 PMCID: PMC3963994 DOI: 10.1371/journal.pone.0093121] [Citation(s) in RCA: 58] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2013] [Accepted: 02/28/2014] [Indexed: 12/23/2022] Open
Abstract
Stroke causes life long disabilities where few therapeutic options are available. Using electrical and magnetic stimulation of the brain and physical rehabilitation, recovery of brain function can be enhanced even late after stroke. Animal models support this notion, and housing rodents in an enriched environment (EE) several days after experimental stroke stimulates lost brain function by multisensory mechanisms. We studied the dynamics of functional recovery of rats with a lesion to the fore and hind limb motor areas induced by photothrombosis (PT), and with subsequent housing in either standard (STD) or EE. In this model, skilled motor function is not significantly enhanced by enriched housing, while the speed of recovery of sensori-motor function substantially improves over the 9-week study period. In particular, this stroke lesion completely obliterates the fore and hind limb placing ability when visual and whisker guidance is prevented, a deficit that persists for up to 9 weeks of recovery, but that is markedly restored within 2 weeks by enriched housing. Enriched housing after stroke also leads to a significant loss of perineuronal net (PNN) immunoreactivity; detection of aggrecan protein backbone with AB1031 antibody was decreased by 13–22%, and labelling of a glycan moiety of aggrecan with Cat-315 antibody was reduced by 25–30% in the peri-infarct area and in the somatosensory cortex, respectively. The majority of these cells are parvalbumin/GABA inhibitory interneurons that are important in sensori-information processing. We conclude that damage to the fore and hind limb motor areas provides a model of loss of limb placing response without visual guidance, a deficit also seen in more than 50% of stroke patients. This loss is amenable to recovery induced by multiple sensory stimulation and correlates with a decrease in aggrecan-containing PNNs around inhibitory interneurons. Modulating the PNN structure after ischemic damage may provide new therapies enhancing tactile/proprioceptive function after stroke.
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Affiliation(s)
- Alexandre Madinier
- Laboratory for Experimental Brain Research, Division of Neurosurgery, Department of Clinical Sciences, Lund University, Lund, Sweden
| | - Miriana Jlenia Quattromani
- Laboratory for Experimental Brain Research, Division of Neurosurgery, Department of Clinical Sciences, Lund University, Lund, Sweden
| | - Carin Sjölund
- Laboratory for Experimental Brain Research, Division of Neurosurgery, Department of Clinical Sciences, Lund University, Lund, Sweden
| | - Karsten Ruscher
- Laboratory for Experimental Brain Research, Division of Neurosurgery, Department of Clinical Sciences, Lund University, Lund, Sweden
| | - Tadeusz Wieloch
- Laboratory for Experimental Brain Research, Division of Neurosurgery, Department of Clinical Sciences, Lund University, Lund, Sweden
- * E-mail:
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Lavrnja I, Trifunovic S, Ajdzanovic V, Pekovic S, Bjelobaba I, Stojiljkovic M, Milosevic V. Sensorimotor cortex ablation induces time-dependent response of ACTH cells in adult rats: behavioral, immunohistomorphometric and hormonal study. Physiol Behav 2013; 125:30-7. [PMID: 24291385 DOI: 10.1016/j.physbeh.2013.11.005] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2013] [Revised: 04/04/2013] [Accepted: 11/19/2013] [Indexed: 11/20/2022]
Abstract
Traumatic brain injury (TBI) represents a serious event with far reaching complications, including pituitary dysfunction. Pars distalis corticotropes (ACTH cells), that represent the active module of hypothalamo-pituitary-adrenocortical axis, seem to be affected as well. Since pituitary failure after TBI has been associated with neurobehavioral impairments the aim of this study was to evaluate the effects of TBI on recovery of motor functions, morphology and secretory activity of ACTH cells in the pituitary of adult rats. Wistar male rats, initially exposed to sensorimotor cortex ablation (SCA), were sacrificed at the 2nd, 7th, 14th and 30th days post-surgery (dps). A beam walking test was used to evaluate the recovery of motor functions. Pituitary glands and blood were collected for morphological and hormonal analyses. During the first two weeks post-injury increased recovery of locomotor function was detected, reaching almost the control value at day 30. SCA induces significant increase of pituitary weights compared to their time-matched controls. The volume of ACTH-immunopositive cells was reduced at the 7th dps, while at the 14th dps their volume was enlarged, in comparison to corresponding sham controls. Volume density of ACTH cells was increased only at 14th dps, while at day 30 this increase was insignificant. The plasma level of ACTH transiently increased after the injury. The most pronounced changes were observed at the 7th and 14th dps, and were followed by decrease toward control levels at the 30th dps. Thus, temporal changes in the hypothalamic-pituitary-adrenal axis after traumatic brain injury appear to correlate with the recovery process.
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Affiliation(s)
- Irena Lavrnja
- Department of Neurobiology, Institute for Biological Research "Sinisa Stankovic", University of Belgrade, Belgrade, Serbia.
| | - Svetlana Trifunovic
- Department of Cytology, Institute for Biological Research "Sinisa Stankovic", University of Belgrade, Belgrade, Serbia
| | - Vladimir Ajdzanovic
- Department of Cytology, Institute for Biological Research "Sinisa Stankovic", University of Belgrade, Belgrade, Serbia
| | - Sanja Pekovic
- Department of Neurobiology, Institute for Biological Research "Sinisa Stankovic", University of Belgrade, Belgrade, Serbia
| | - Ivana Bjelobaba
- Department of Neurobiology, Institute for Biological Research "Sinisa Stankovic", University of Belgrade, Belgrade, Serbia
| | - Mirjana Stojiljkovic
- Department of Neurobiology, Institute for Biological Research "Sinisa Stankovic", University of Belgrade, Belgrade, Serbia
| | - Verica Milosevic
- Department of Cytology, Institute for Biological Research "Sinisa Stankovic", University of Belgrade, Belgrade, Serbia
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Small-molecule modulation of neurotrophin receptors: a strategy for the treatment of neurological disease. Nat Rev Drug Discov 2013; 12:507-25. [PMID: 23977697 DOI: 10.1038/nrd4024] [Citation(s) in RCA: 198] [Impact Index Per Article: 18.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Neurotrophins and their receptors modulate multiple signalling pathways to regulate neuronal survival and to maintain axonal and dendritic networks and synaptic plasticity. Neurotrophins have potential for the treatment of neurological diseases. However, their therapeutic application has been limited owing to their poor plasma stability, restricted nervous system penetration and, importantly, the pleiotropic actions that derive from their concomitant binding to multiple receptors. One strategy to overcome these limitations is to target individual neurotrophin receptors — such as tropomyosin receptor kinase A (TRKA), TRKB, TRKC, the p75 neurotrophin receptor or sortilin — with small-molecule ligands. Such small molecules might also modulate various aspects of these signalling pathways in ways that are distinct from the programmes triggered by native neurotrophins. By departing from conventional neurotrophin signalling, these ligands might provide novel therapeutic options for a broad range of neurological indications.
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Park K, Biederer T. Neuronal adhesion and synapse organization in recovery after brain injury. FUTURE NEUROLOGY 2013; 8:555-567. [PMID: 24489481 DOI: 10.2217/fnl.13.35] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
Few specific therapeutic targets exist to manage brain injury, despite the prevalence of stroke or traumatic brain injury. With traumatic brain injury, characteristic neuronal changes include axonal swelling and degeneration, and the loss of synapses, the sites of communication between neurons. This is followed by axonal sprouting and alterations in synaptic markers in recovery. The resulting changes in neuronal connectivity are likely to contribute to the effects of traumatic brain injury on cognitive functions and the underlying mechanisms may represent points of therapeutic intervention. In agreement, animal studies implicate adhesion and signaling molecules that organize synapses as molecular players in neuronal recovery. In this article, the authors focus on the role of cell surface interactions in the recovery after brain injury in humans and animals. The authors review cellular and synaptic alterations that occur with injury and how changes in cell adhesion, protein expression and modification may be involved in recovery. The changes in neuronal surface interactions as potential targets and their possible value for the development of therapeutics are also discussed.
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Affiliation(s)
- Kellie Park
- Department of Anesthesiology, Yale University School of Medicine, New Haven, CT, USA
| | - Thomas Biederer
- Department of Molecular Biophysics & Biochemistry, Yale University School of Medicine, New Haven, CT, USA ; Program in Cellular Neuroscience, Neurodegeneration & Repair, Yale University School of Medicine, New Haven, CT, USA
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Harris NG, Nogueira MSM, Verley DR, Sutton RL. Chondroitinase enhances cortical map plasticity and increases functionally active sprouting axons after brain injury. J Neurotrauma 2013; 30:1257-69. [PMID: 23517225 DOI: 10.1089/neu.2012.2737] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023] Open
Abstract
The beneficial effect of interventions with chondroitinase ABC enzyme to reduce axon growth-inhibitory chondroitin sulphate side chains after central nervous system injuries has been mainly attributed to enhanced axonal sprouting. After traumatic brain injury (TBI), it is unknown whether newly sprouting axons that occur as a result of interventional strategies are able to functionally contribute to existing circuitry, and it is uncertain whether maladaptive sprouting occurs to increase the well-known risk for seizure activity after TBI. Here, we show that after a controlled cortical impact injury in rats, chondroitinase infusion into injured cortex at 30 min and 3 days reduced c-Fos⁺ cell staining resulting from the injury alone at 1 week postinjury, indicating that at baseline, abnormal spontaneous activity is likely to be reduced, not increased, with this type of intervention. c-Fos⁺ cell staining elicited by neural activity from stimulation of the affected forelimb 1 week after injury was significantly enhanced by chondroitinase, indicating a widespread effect on cortical map plasticity. Underlying this map plasticity was a larger contribution of neuronal, rather than glial cells and an absence of c-Fos⁺ cells surrounded by perineuronal nets that were normally present in stimulated naïve rats. After injury, chondroitin sulfate proteoglycan digestion produced the expected increase in growth-associated protein 43-positive axons and perikarya, of which a significantly greater number were double labeled for c-Fos after intervention with chondroitinase, compared to vehicle. These data indicate that chondroitinase produces significant gains in cortical map plasticity after TBI, and that either axonal sprouting and/or changes in perineuronal nets may underlie this effect. Chondroitinase dampens, rather than increases nonspecific c-Fos activity after brain injury, and induction of axonal sprouting is not maladaptive because greater numbers are functionally active and provide a significant contribution to forelimb circuitry after brain injury.
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Affiliation(s)
- Neil G Harris
- Department of Neurosurgery, David Geffen School of Medicine at UCLA, Box 957039, Los Angeles, CA 90095-7039, USA.
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Harris NG, Chen SF, Pickard JD. Cortical reorganization after experimental traumatic brain injury: a functional autoradiography study. J Neurotrauma 2013; 30:1137-46. [PMID: 23305562 PMCID: PMC3700473 DOI: 10.1089/neu.2012.2785] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Cortical sensorimotor (SM) maps are a useful readout for providing a global view of the underlying status of evoked brain function, as well as a gross overview of ongoing mechanisms of plasticity. Recent evidence in the rat controlled cortical impact (CCI) injury model shows that the ipsilesional (injured) hemisphere is temporarily permissive for axon sprouting. This would predict that size and spatial alterations in cortical maps may occur much earlier than previously tested and that they might be useful as potential markers of the postinjury plasticity period as well as indicators of outcome. We investigated the evolution of changes in brain activation evoked by affected hindlimb electrical stimulation at 4, 7, and 30 days following CCI or sham injury over the hindlimb cortical region of adult rats. [(14)C]-iodoantipyrine autoradiography was used to quantitatively examine the local cerebral blood flow changes in response to hindlimb stimulation as a marker for neuronal activity. The results show that although ipsilesional hindlimb SM activity was persistently depressed from 4 days, additional novel regions of ipsilesional activity appeared concurrently within SM barrel and S2 regions as well as posterior auditory cortex. Simultaneously with this was the appearance of evoked activity within the intact, contralesional cortex that was maximal at 4 and 7 days, compared to stimulated sham-injured rats, where activation was solely unilateral. By 30 days, however, contralesional activation had greatly subsided and existing ipsilesional activity was enhanced within the same novel cortical regions that were identified acutely. These data indicate that significant reorganization of the cortical SM maps occurs after injury that evolves with a particular postinjury time course. We discuss these data in terms of the known mechanisms of plasticity that are likely to underlie these map changes, with particular reference to the differences and similarities that exist between rodent models of stroke and traumatic brain injury.
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Affiliation(s)
- Neil G Harris
- UCLA Brain Injury Research Center, Department of Neurosurgery, David Geffen School of Medicine at UCLA, Los Angeles, California 90095-7039, USA.
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Yi JH, Katagiri Y, Susarla B, Figge D, Symes AJ, Geller HM. Alterations in sulfated chondroitin glycosaminoglycans following controlled cortical impact injury in mice. J Comp Neurol 2013; 520:3295-313. [PMID: 22628090 DOI: 10.1002/cne.23156] [Citation(s) in RCA: 72] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Chondroitin sulfate proteoglycans (CSPGs) play a pivotal role in many neuronal growth mechanisms including axon guidance and the modulation of repair processes following injury to the spinal cord or brain. Many actions of CSPGs in the central nervous system (CNS) are governed by the specific sulfation pattern on the glycosaminoglycan (GAG) chains attached to CSPG core proteins. To elucidate the role of CSPGs and sulfated GAG chains following traumatic brain injury (TBI), controlled cortical impact injury of mild to moderate severity was performed over the left sensory motor cortex in mice. Using immunoblotting and immunostaining, we found that TBI resulted in an increase in the CSPGs neurocan and NG2 expression in a tight band surrounding the injury core, which overlapped with the presence of 4-sulfated CS GAGs but not with 6-sulfated GAGs. This increase was observed as early as 7 days post injury (dpi), and persisted for up to 28 dpi. Labeling with markers against microglia/macrophages, NG2+ cells, fibroblasts, and astrocytes showed that these cells were all localized in the area, suggesting multiple origins of chondroitin-4-sulfate increase. TBI also caused a decrease in the expression of aggrecan and phosphacan in the pericontusional cortex with a concomitant reduction in the number of perineuronal nets. In summary, we describe a dual response in CSPGs whereby they may be actively involved in complex repair processes following TBI.
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Affiliation(s)
- Jae-Hyuk Yi
- Developmental Neurobiology Section, Cell Biology and Physiology Center, National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda, Maryland 20892, USA
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Perineuronal nets protect fast-spiking interneurons against oxidative stress. Proc Natl Acad Sci U S A 2013; 110:9130-5. [PMID: 23671099 DOI: 10.1073/pnas.1300454110] [Citation(s) in RCA: 362] [Impact Index Per Article: 32.9] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023] Open
Abstract
A hallmark of schizophrenia pathophysiology is the dysfunction of cortical inhibitory GABA neurons expressing parvalbumin, which are essential for coordinating neuronal synchrony during various sensory and cognitive tasks. The high metabolic requirements of these fast-spiking cells may render them susceptible to redox dysregulation and oxidative stress. Using mice carrying a genetic redox imbalance, we demonstrate that extracellular perineuronal nets, which constitute a specialized polyanionic matrix enwrapping most of these interneurons as they mature, play a critical role in the protection against oxidative stress. These nets limit the effect of genetically impaired antioxidant systems and/or excessive reactive oxygen species produced by severe environmental insults. We observe an inverse relationship between the robustness of the perineuronal nets around parvalbumin cells and the degree of intracellular oxidative stress they display. Enzymatic degradation of the perineuronal nets renders mature parvalbumin cells and fast rhythmic neuronal synchrony more susceptible to oxidative stress. In parallel, parvalbumin cells enwrapped with mature perineuronal nets are better protected than immature parvalbumin cells surrounded by less-condensed perineuronal nets. Although the perineuronal nets act as a protective shield, they are also themselves sensitive to excess oxidative stress. The protection might therefore reflect a balance between the oxidative burden on perineuronal net degradation and the capacity of the system to maintain the nets. Abnormal perineuronal nets, as observed in the postmortem patient brain, may thus underlie the vulnerability and functional impairment of pivotal inhibitory circuits in schizophrenia.
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Álvarez XA, Figueroa J, Muresanu D. Peptidergic drugs for the treatment of traumatic brain injury. FUTURE NEUROLOGY 2013. [DOI: 10.2217/fnl.12.95] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Traumatic brain injury (TBI) is a devastating medical condition that has an enormous socioeconomic impact because it affects more than 10 million people annually worldwide and is associated with high rates of hospitalization, mortality and disability. Although TBI survival has improved continuously for decades, particularly in developing countries, implementation of an effective drug therapy for TBI represents an unmet clinical need. All confirmatory trials conducted to date with drugs targeting a single TBI pathological pathway failed to show clinical efficacy, probably because TBI pathophysiology involves multiple cellular and molecular mechanisms of secondary brain damage. According to current scientific evidence of the participation of peptide-mediated mechanisms in the processes of brain injury and repair after TBI, peptidergic drugs represent a multimodal therapy alternative to improve acute outcome and long-term recovery in TBI patients. Preliminary randomized-controlled clinical trials and open-label studies conducted to date with the peptidergic drug Cerebrolysin® (Ever Neuro Pharma GmbH, Unterach, Austria) and with the endogenous neuropeptides progesterone and erythropoietin, showed positive clinical results. Cerebrolysin-treated patients had a faster clinical recovery, a shorter hospitalization time and a better long-term outcome. Treatment with progesterone showed advantages over placebo regarding TBI mortality and clinical outcome, whereas erythropoietin only reduced mortality. Further validation of these promising findings in confirmatory randomized-controlled clinical trials is warranted. This article reviews the scientific basis and clinical evidence on the development of multimodal peptidergic drugs as a therapeutic option for the effective treatment of TBI patients.
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Affiliation(s)
| | - Jesús Figueroa
- Rehabilitation Department, Santiago University Hospital, Santiago de Compostela, Spain
| | - Dafin Muresanu
- Department of Neurology, University of Medicine & Pharmacy ‘Iuliu Hatieganu’, Cluj-Napoca, Romania
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Magnetic stimulation modulates structural synaptic plasticity and regulates BDNF–TrkB signal pathway in cultured hippocampal neurons. Neurochem Int 2013. [DOI: 10.1016/j.neuint.2012.11.010] [Citation(s) in RCA: 75] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
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Kozlowski DA, Leasure JL, Schallert T. The Control of Movement Following Traumatic Brain Injury. Compr Physiol 2013; 3:121-39. [DOI: 10.1002/cphy.c110005] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
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Aungst S, England PM, Thompson SM. Critical role of trkB receptors in reactive axonal sprouting and hyperexcitability after axonal injury. J Neurophysiol 2012; 109:813-24. [PMID: 23155176 DOI: 10.1152/jn.00869.2012] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Traumatic brain injury (TBI) causes many long-term neurological complications. Some of these conditions, such as posttraumatic epilepsy, are characterized by increased excitability that typically arises after a latent period lasting from months to years, suggesting that slow injury-induced processes are critical. We tested the hypothesis that trkB activation promotes delayed injury-induced hyperexcitability in part by promoting reactive axonal sprouting. We modeled penetrative TBI with transection of the Schaffer collateral pathway in knock-in mice having an introduced mutation in the trkB receptor (trkB(F616A)) that renders it susceptible to inhibition by the novel small molecule 1NMPP1. We observed that trkB activation was increased in area CA3 1 day after injury and that expression of a marker of axonal growth, GAP43, was increased 7 days after lesion. Extracellular field potentials in stratum pyramidale of area CA3 in acute slices from sham-operated and lesioned mice were normal in control saline. Abnormal bursts of population spikes were observed under conditions that were mildly proconvulsive but only in slices taken from mice lesioned 7-21 days earlier and not in slices from control mice. trkB activation, GAP43 upregulation, and hyperexcitability were diminished by systemic administration of 1NMPP1 for 7 days after the lesion. Synaptic transmission from area CA3 to area CA1 recovered 7 days after lesion in untreated mice but not in mice treated with 1NMPP1. We conclude that trkB receptor activation and reactive axonal sprouting are critical factors in injury-induced hyperexcitability and may contribute to the neurological complications of TBI.
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Affiliation(s)
- Stephanie Aungst
- Department of Physiology and Program in Neuroscience, University of Maryland School of Medicine, Baltimore, MD, USA
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Ng JMJ, Chen MJ, Leung JYK, Peng ZF, Manikandan J, Qi RZ, Chuah MI, West AK, Vickers JC, Lu J, Cheung NS, Chung RS. Transcriptional insights on the regenerative mechanics of axotomized neurons in vitro. J Cell Mol Med 2012; 16:789-811. [PMID: 21711447 PMCID: PMC3822849 DOI: 10.1111/j.1582-4934.2011.01361.x] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023] Open
Abstract
Axotomized neurons have the innate ability to undergo regenerative sprouting but this is often impeded by the inhibitory central nervous system environment. To gain mechanistic insights into the key molecular determinates that specifically underlie neuronal regeneration at a transcriptomic level, we have undertaken a DNA microarray study on mature cortical neuronal clusters maintained in vitro at 8, 15, 24 and 48 hrs following complete axonal severance. A total of 305 genes, each with a minimum fold change of ±1.5 for at least one out of the four time points and which achieved statistical significance (one-way ANOVA, P < 0.05), were identified by DAVID and classified into 14 different functional clusters according to Gene Ontology. From our data, we conclude that post-injury regenerative sprouting is an intricate process that requires two distinct pathways. Firstly, it involves restructuring of the neurite cytoskeleton, determined by compound actin and microtubule dynamics, protein trafficking and concomitant modulation of both guidance cues and neurotrophic factors. Secondly, it elicits a cell survival response whereby genes are regulated to protect against oxidative stress, inflammation and cellular ion imbalance. Our data reveal that neurons have the capability to fight insults by elevating biological antioxidants, regulating secondary messengers, suppressing apoptotic genes, controlling ion-associated processes and by expressing cell cycle proteins that, in the context of neuronal injury, could potentially have functions outside their normal role in cell division. Overall, vigilant control of cell survival responses against pernicious secondary processes is vital to avoid cell death and ensure successful neurite regeneration.
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Affiliation(s)
- Jian Ming Jeremy Ng
- Menzies Research Institute, University of Tasmania, Hobart, Tasmania, Australia
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