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Dogra S, Arabshahi S, Wei J, Saidenberg L, Kang SK, Chung S, Laine A, Lui YW. Functional Connectivity Changes on Resting-State fMRI after Mild Traumatic Brain Injury: A Systematic Review. AJNR Am J Neuroradiol 2024; 45:795-801. [PMID: 38637022 PMCID: PMC11288594 DOI: 10.3174/ajnr.a8204] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2023] [Accepted: 01/22/2024] [Indexed: 04/20/2024]
Abstract
BACKGROUND Mild traumatic brain injury is theorized to cause widespread functional changes to the brain. Resting-state fMRI may be able to measure functional connectivity changes after traumatic brain injury, but resting-state fMRI studies are heterogeneous, using numerous techniques to study ROIs across various resting-state networks. PURPOSE We systematically reviewed the literature to ascertain whether adult patients who have experienced mild traumatic brain injury show consistent functional connectivity changes on resting-state -fMRI, compared with healthy patients. DATA SOURCES We used 5 databases (PubMed, EMBASE, Cochrane Central, Scopus, Web of Science). STUDY SELECTION Five databases (PubMed, EMBASE, Cochrane Central, Scopus, and Web of Science) were searched for research published since 2010. Search strategies used keywords of "functional MR imaging" and "mild traumatic brain injury" as well as related terms. All results were screened at the abstract and title levels by 4 reviewers according to predefined inclusion and exclusion criteria. For full-text inclusion, each study was evaluated independently by 2 reviewers, with discordant screening settled by consensus. DATA ANALYSIS Data regarding article characteristics, cohort demographics, fMRI scan parameters, data analysis processing software, atlas used, data characteristics, and statistical analysis information were extracted. DATA SYNTHESIS Across 66 studies, 80 areas were analyzed 239 times for at least 1 time point, most commonly using independent component analysis. The most analyzed areas and networks were the whole brain, the default mode network, and the salience network. Reported functional connectivity changes varied, though there may be a slight trend toward decreased whole-brain functional connectivity within 1 month of traumatic brain injury and there may be differences based on the time since injury. LIMITATIONS Studies of military, sports-related traumatic brain injury, and pediatric patients were excluded. Due to the high number of relevant studies and data heterogeneity, we could not be as granular in the analysis as we would have liked. CONCLUSIONS Reported functional connectivity changes varied, even within the same region and network, at least partially reflecting differences in technical parameters, preprocessing software, and analysis methods as well as probable differences in individual injury. There is a need for novel rs-fMRI techniques that better capture subject-specific functional connectivity changes.
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Affiliation(s)
- Siddhant Dogra
- From the Department of Radiology (S.D., J.W., S.K.K., S.C., Y.L.), New York University Grossman School of Medicine, New York, New York
| | - Soroush Arabshahi
- Department of Biomedical Engineering (S.A., A.L.), Department of Radiology, Columbia University, New York, New York
| | - Jason Wei
- From the Department of Radiology (S.D., J.W., S.K.K., S.C., Y.L.), New York University Grossman School of Medicine, New York, New York
| | - Lucia Saidenberg
- Department of Neurology (L.S.), Department of Radiology. New York University Grossman School of Medicine, New York, New York
| | - Stella K Kang
- From the Department of Radiology (S.D., J.W., S.K.K., S.C., Y.L.), New York University Grossman School of Medicine, New York, New York
| | - Sohae Chung
- From the Department of Radiology (S.D., J.W., S.K.K., S.C., Y.L.), New York University Grossman School of Medicine, New York, New York
| | - Andrew Laine
- Department of Biomedical Engineering (S.A., A.L.), Department of Radiology, Columbia University, New York, New York
| | - Yvonne W Lui
- From the Department of Radiology (S.D., J.W., S.K.K., S.C., Y.L.), New York University Grossman School of Medicine, New York, New York
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Guerrero-Gonzalez JM, Kirk GR, Birn R, Bigler ED, Bowen K, Broman AT, Rosario BL, Butt W, Beers SR, Bell MJ, Alexander AL, Ferrazzano PA. Multi-modal MRI of hippocampal morphometry and connectivity after pediatric severe TBI. Brain Imaging Behav 2024; 18:159-170. [PMID: 37955810 PMCID: PMC10844146 DOI: 10.1007/s11682-023-00818-x] [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] [Accepted: 10/22/2023] [Indexed: 11/14/2023]
Abstract
This investigation explores memory performance using the California Verbal Learning Test in relation to morphometric and connectivity measures of the memory network in severe traumatic brain injury. Twenty-two adolescents with severe traumatic brain injury were recruited for multimodal MRI scanning 1-2 years post-injury at 13 participating sites. Analyses included hippocampal volume derived from anatomical T1-weighted imaging, fornix white matter microstructure from diffusion tensor imaging, and hippocampal resting-state functional magnetic resonance imaging connectivity as well as diffusion-based structural connectivity. A typically developing control cohort of forty-nine age-matched children also underwent scanning and neurocognitive assessment. Results showed hippocampus volume was decreased in traumatic brain injury with respect to controls. Further, hippocampal volume loss was associated with worse performance on memory and learning in traumatic brain injury subjects. Similarly, hippocampal fornix fractional anisotropy was reduced in traumatic brain injury with respect to controls, while decreased fractional anisotropy in the hippocampal fornix also was associated with worse performance on memory and learning in traumatic brain injury subjects. Additionally, reduced structural connectivity of left hippocampus to thalamus and calcarine sulcus was associated with memory and learning in traumatic brain injury subjects. Functional connectivity in the left hippocampal network was also associated with memory and learning in traumatic brain injury subjects. These regional findings from a multi-modal neuroimaging approach should not only be useful for gaining valuable insight into traumatic brain injury induced memory and learning disfunction, but may also be informative for monitoring injury progression, recovery, and for developing rehabilitation as well as therapy strategies.
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Affiliation(s)
- Jose M Guerrero-Gonzalez
- Department of Medical Physics, University of Wisconsin School of Medicine and Public Health, Madison, WI, USA.
- Waisman Center, University of Wisconsin-Madison, 1500 Highland Avenue, Madison, WI, 53705, USA.
| | - Gregory R Kirk
- Waisman Center, University of Wisconsin-Madison, 1500 Highland Avenue, Madison, WI, 53705, USA
| | - Rasmus Birn
- Department of Medical Physics, University of Wisconsin School of Medicine and Public Health, Madison, WI, USA
- Department of Psychiatry, University of Wisconsin School of Medicine and Public Health, Madison, WI, USA
| | - Erin D Bigler
- Department of Psychology and Neuroscience Center, Brigham Young University, Provo, UT, USA
- Department of Neurology & Department of Psychiatry, University of Utah, Salt Lake City, UT, USA
| | | | - Aimee T Broman
- Department of Biostatistics, University of Wisconsin-Madison, Madison, WI, USA
| | - Bedda L Rosario
- Department of Epidemiology, School of Medicine, University of Pittsburgh, Pittsburgh, Pennsylvania, USA
| | - Warwick Butt
- Department of Critical Care, Faculty of Medicine, Melbourne University, Melbourne, Australia
| | - Sue R Beers
- Department of Psychiatry, School of Medicine, University of Pittsburgh, Pittsburgh, Pennsylvania, USA
| | - Michael J Bell
- Department of Pediatrics, Children's National Medical Center, Washington, DC, USA
| | - Andrew L Alexander
- Department of Medical Physics, University of Wisconsin School of Medicine and Public Health, Madison, WI, USA
- Department of Psychiatry, University of Wisconsin School of Medicine and Public Health, Madison, WI, USA
- Waisman Center, University of Wisconsin-Madison, 1500 Highland Avenue, Madison, WI, 53705, USA
| | - Peter A Ferrazzano
- Department of Pediatrics, University of Wisconsin School of Medicine and Public Health, Madison, WI, USA
- Waisman Center, University of Wisconsin-Madison, 1500 Highland Avenue, Madison, WI, 53705, USA
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Khan SS, Khatik GL, Datusalia AK. Strategies for Treatment of Disease-Associated Dementia Beyond Alzheimer's Disease: An Update. Curr Neuropharmacol 2023; 21:309-339. [PMID: 35410602 PMCID: PMC10190146 DOI: 10.2174/1570159x20666220411083922] [Citation(s) in RCA: 8] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2021] [Revised: 02/27/2022] [Accepted: 04/03/2022] [Indexed: 11/22/2022] Open
Abstract
Memory, cognition, dementia, and neurodegeneration are complexly interlinked processes with various mechanistic pathways, leading to a range of clinical outcomes. They are strongly associated with pathological conditions like Alzheimer's disease, Parkinson's disease, schizophrenia, and stroke and are a growing concern for their timely diagnosis and management. Several cognitionenhancing interventions for management include non-pharmacological interventions like diet, exercise, and physical activity, while pharmacological interventions include medicinal agents, herbal agents, and nutritional supplements. This review critically analyzed and discussed the currently available agents under different drug development phases designed to target the molecular targets, including cholinergic receptor, glutamatergic system, GABAergic targets, glycine site, serotonergic targets, histamine receptors, etc. Understanding memory formation and pathways involved therein aids in opening the new gateways to treating cognitive disorders. However, clinical studies suggest that there is still a dearth of knowledge about the pathological mechanism involved in neurological conditions, making the dropouts of agents from the initial phases of the clinical trial. Hence, a better understanding of the disease biology, mode of drug action, and interlinked mechanistic pathways at a molecular level is required.
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Affiliation(s)
- Sabiya Samim Khan
- Department of Pharmacology and Toxicology, National Institute of Pharmaceutical Education and Research (NIPER) Raebareli, Lucknow (UP) India
| | - Gopal L. Khatik
- Department of Medicinal Chemistry, National Institute of Pharmaceutical Education and Research (NIPER) Raebareli, Lucknow (UP) India
| | - Ashok K. Datusalia
- Department of Pharmacology and Toxicology, National Institute of Pharmaceutical Education and Research (NIPER) Raebareli, Lucknow (UP) India
- Department of Regulatory Toxicology, National Institute of Pharmaceutical Education and Research (NIPER) Raebareli, Lucknow (UP) India
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Pinky NN, Debert CT, Dukelow SP, Benson BW, Harris AD, Yeates KO, Emery CA, Goodyear BG. Multimodal magnetic resonance imaging of youth sport-related concussion reveals acute changes in the cerebellum, basal ganglia, and corpus callosum that resolve with recovery. Front Hum Neurosci 2022; 16:976013. [PMID: 36337852 PMCID: PMC9626521 DOI: 10.3389/fnhum.2022.976013] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2022] [Accepted: 09/23/2022] [Indexed: 11/28/2022] Open
Abstract
Magnetic resonance imaging (MRI) can provide a number of measurements relevant to sport-related concussion (SRC) symptoms; however, most studies to date have used a single MRI modality and whole-brain exploratory analyses in attempts to localize concussion injury. This has resulted in highly variable findings across studies due to wide ranging symptomology, severity and nature of injury within studies. A multimodal MRI, symptom-guided region-of-interest (ROI) approach is likely to yield more consistent results. The functions of the cerebellum and basal ganglia transcend many common concussion symptoms, and thus these regions, plus the white matter tracts that connect or project from them, constitute plausible ROIs for MRI analysis. We performed diffusion tensor imaging (DTI), resting-state functional MRI, quantitative susceptibility mapping (QSM), and cerebral blood flow (CBF) imaging using arterial spin labeling (ASL), in youth aged 12-18 years following SRC, with a focus on the cerebellum, basal ganglia and white matter tracts. Compared to controls similar in age, sex and sport (N = 20), recent SRC youth (N = 29; MRI at 8 ± 3 days post injury) exhibited increased susceptibility in the cerebellum (p = 0.032), decreased functional connectivity between the caudate and each of the pallidum (p = 0.035) and thalamus (p = 0.021), and decreased diffusivity in the mid-posterior corpus callosum (p < 0.038); no changes were observed in recovered asymptomatic youth (N = 16; 41 ± 16 days post injury). For recent symptomatic-only SRC youth (N = 24), symptom severity was associated with increased susceptibility in the superior cerebellar peduncles (p = 0.011) and reduced activity in the cerebellum (p = 0.013). Fewer days between injury and MRI were associated with reduced cerebellar-parietal functional connectivity (p < 0.014), reduced activity of the pallidum (p = 0.002), increased CBF in the caudate (p = 0.005), and reduced diffusivity in the central corpus callosum (p < 0.05). Youth SRC is associated with acute cerebellar inflammation accompanied by reduced cerebellar activity and cerebellar-parietal connectivity, as well as structural changes of the middle regions of the corpus callosum accompanied by functional changes of the caudate, all of which resolve with recovery. Early MRI post-injury is important to establish objective MRI-based indicators for concussion diagnosis, recovery assessment and prediction of outcome.
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Affiliation(s)
- Najratun Nayem Pinky
- Department of Biomedical Engineering, University of Calgary, Calgary, AB, Canada
| | - Chantel T. Debert
- Department of Clinical Neurosciences, University of Calgary, Calgary, AB, Canada
- Hotchkiss Brain Institute, University of Calgary, Calgary, AB, Canada
| | - Sean P. Dukelow
- Department of Clinical Neurosciences, University of Calgary, Calgary, AB, Canada
- Hotchkiss Brain Institute, University of Calgary, Calgary, AB, Canada
| | - Brian W. Benson
- Department of Clinical Neurosciences, University of Calgary, Calgary, AB, Canada
- Canadian Sport Institute Calgary, University of Calgary, Calgary, AB, Canada
- Benson Concussion Institute, University of Calgary, Calgary, AB, Canada
| | - Ashley D. Harris
- Hotchkiss Brain Institute, University of Calgary, Calgary, AB, Canada
- Department of Radiology, University of Calgary, Calgary, AB, Canada
- Alberta Children’s Hospital Research Institute, University of Calgary, Calgary, AB, Canada
| | - Keith O. Yeates
- Hotchkiss Brain Institute, University of Calgary, Calgary, AB, Canada
- Alberta Children’s Hospital Research Institute, University of Calgary, Calgary, AB, Canada
- Department of Psychology, University of Calgary, Calgary, AB, Canada
| | - Carolyn A. Emery
- Hotchkiss Brain Institute, University of Calgary, Calgary, AB, Canada
- Alberta Children’s Hospital Research Institute, University of Calgary, Calgary, AB, Canada
- Department of Pediatrics, University of Calgary, Calgary, AB, Canada
- Department of Community Health Sciences, University of Calgary, Calgary, AB, Canada
- Sports Injury Prevention Research Centre, University of Calgary, Calgary, AB, Canada
| | - Bradley G. Goodyear
- Department of Clinical Neurosciences, University of Calgary, Calgary, AB, Canada
- Hotchkiss Brain Institute, University of Calgary, Calgary, AB, Canada
- Department of Radiology, University of Calgary, Calgary, AB, Canada
- Department of Psychiatry, University of Calgary, Calgary, AB, Canada
- Seaman Family MR Research Centre, University of Calgary, Calgary, AB, Canada
- *Correspondence: Bradley G. Goodyear,
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Wu Z, Cao M, Di X, Wu K, Gao Y, Li X. Regional Topological Aberrances of White Matter- and Gray Matter-Based Functional Networks for Attention Processing May Foster Traumatic Brain Injury-Related Attention Deficits in Adults. Brain Sci 2021; 12:brainsci12010016. [PMID: 35053760 PMCID: PMC8774280 DOI: 10.3390/brainsci12010016] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2021] [Revised: 12/21/2021] [Accepted: 12/22/2021] [Indexed: 12/31/2022] Open
Abstract
Traumatic brain injury (TBI) is highly prevalent in adults. TBI-related functional brain alterations have been linked with common post-TBI neurobehavioral sequelae, with unknown neural substrates. This study examined the systems-level functional brain alterations in white matter (WM) and gray matter (GM) for visual sustained-attention processing, and their interactions and contributions to post-TBI attention deficits. Task-based functional MRI data were collected from 42 adults with TBI and 43 group-matched normal controls (NCs), and analyzed using the graph theoretic technique. Global and nodal topological properties were calculated and compared between the two groups. Correlation analyses were conducted between the neuroimaging measures that showed significant between-group differences and the behavioral symptom measures in attention domain in the groups of TBI and NCs, respectively. Significantly altered nodal efficiencies and/or degrees in several WM and GM nodes were reported in the TBI group, including the posterior corona radiata (PCR), posterior thalamic radiation (PTR), postcentral gyrus (PoG), and superior temporal sulcus (STS). Subjects with TBI also demonstrated abnormal systems-level functional synchronization between the PTR and STS in the right hemisphere, hypo-interaction between the PCR and PoG in the left hemisphere, as well as the involvement of systems-level functional aberrances in the PCR in TBI-related behavioral impairments in the attention domain. The findings of the current study suggest that TBI-related systems-level functional alterations associated with these two major-association WM tracts, and their anatomically connected GM regions may play critical role in TBI-related behavioral deficits in attention domains.
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Affiliation(s)
- Ziyan Wu
- Department of Electrical and Computer Engineering, New Jersey Institute of Technology, Newark, NJ 07102, USA;
| | - Meng Cao
- Department of Biomedical Engineering, New Jersey Institute of Technology, Newark, NJ 07102, USA; (M.C.); (X.D.)
| | - Xin Di
- Department of Biomedical Engineering, New Jersey Institute of Technology, Newark, NJ 07102, USA; (M.C.); (X.D.)
| | - Kai Wu
- School of Biomedical Sciences and Engineering, South China University of Technology, Guangzhou 510630, China;
| | - Yu Gao
- Department of Psychology, Brooklyn College, The City University of New York, New York, NY 11210, USA;
- The Graduate Center, The City University of New York, New York, NY 10016, USA
| | - Xiaobo Li
- Department of Electrical and Computer Engineering, New Jersey Institute of Technology, Newark, NJ 07102, USA;
- Department of Biomedical Engineering, New Jersey Institute of Technology, Newark, NJ 07102, USA; (M.C.); (X.D.)
- Correspondence: or ; Tel.: +1-973-596-5880
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Motanis H, Khorasani LN, Giza CC, Harris NG. Peering into the Brain through the Retrosplenial Cortex to Assess Cognitive Function of the Injured Brain. Neurotrauma Rep 2021; 2:564-580. [PMID: 34901949 PMCID: PMC8655812 DOI: 10.1089/neur.2021.0044] [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] [Indexed: 11/12/2022] Open
Abstract
The retrosplenial cortex (RSC) is a posterior cortical area that has been drawing increasing interest in recent years, with a growing number of studies studying its contribution to cognitive and sensory functions. From an anatomical perspective, it has been established that the RSC is extensively and often reciprocally connected with the hippocampus, neocortex, and many midbrain regions. Functionally, the RSC is an important hub of the default-mode network. This endowment, with vast anatomical and functional connections, positions the RSC to play an important role in episodic memory, spatial and contextual learning, sensory-cognitive activities, and multi-modal sensory information processing and integration. Additionally, RSC dysfunction has been reported in cases of cognitive decline, particularly in Alzheimer's disease and stroke. We review the literature to examine whether the RSC can act as a cortical marker of persistent cognitive dysfunction after traumatic brain injury (TBI). Because the RSC is easily accessible at the brain's surface using in vivo techniques, we argue that studying RSC network activity post-TBI can shed light into the mechanisms of less-accessible brain regions, such as the hippocampus. There is a fundamental gap in the TBI field about the microscale alterations occurring post-trauma, and by studying the RSC's neuronal activity at the cellular level we will be able to design better therapeutic tools. Understanding how neuronal activity and interactions produce normal and abnormal activity in the injured brain is crucial to understanding cognitive dysfunction. By using this approach, we expect to gain valuable insights to better understand brain disorders like TBI.
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Affiliation(s)
- Helen Motanis
- UCLA Brain Injury Research Center, Department of Neurosurgery, Geffen Medical School, UCLA Mattel Children's Hospital, University of California at Los Angeles, Los Angeles, California, USA
| | - Laila N. Khorasani
- UCLA Brain Injury Research Center, Department of Neurosurgery, Geffen Medical School, UCLA Mattel Children's Hospital, University of California at Los Angeles, Los Angeles, California, USA
| | - Christopher C. Giza
- UCLA Brain Injury Research Center, Department of Neurosurgery, Geffen Medical School, UCLA Mattel Children's Hospital, University of California at Los Angeles, Los Angeles, California, USA
- Department of Pediatrics, UCLA Mattel Children's Hospital, University of California at Los Angeles, Los Angeles, California, USA
| | - Neil G. Harris
- UCLA Brain Injury Research Center, Department of Neurosurgery, Geffen Medical School, UCLA Mattel Children's Hospital, University of California at Los Angeles, Los Angeles, California, USA
- Intellectual Development and Disabilities Research Center, UCLA Mattel Children's Hospital, University of California at Los Angeles, Los Angeles, California, USA
- *Address correspondence to: Neil G. Harris, PhD, Department of Neurosurgery, University of California at Los Angeles, Wasserman Building, 300 Stein Plaza, Room 551, Los Angeles, CA 90095, USA;
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Abstract
Spinal cord injury (SCI) destroys the sensorimotor pathway and blocks the information flow between the peripheral nerve and the brain, resulting in autonomic function loss. Numerous studies have explored the effects of obstructed information flow on brain structure and function and proved the extensive plasticity of the brain after SCI. Great progress has also been achieved in therapeutic strategies for SCI to restore the "re-innervation" of the cerebral cortex to the limbs to some extent. Although no thorough research has been conducted, the changes of brain structure and function caused by "re-domination" have been reported. This article is a review of the recent research progress on local structure, functional changes, and circuit reorganization of the cerebral cortex after SCI. Alterations of structure and electrical activity characteristics of brain neurons, features of brain functional reorganization, and regulation of brain functions by reconfigured information flow were also explored. The integration of brain function is the basis for the human body to exercise complex/fine movements and is intricately and widely regulated by information flow. Hence, its changes after SCI and treatments should be considered.
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Affiliation(s)
- Can Zhao
- Institute of Rehabilitation Engineering, China Rehabilitation Science Institute, Beijing, China
- School of Rehabilitation, Capital Medical University, Beijing, China
| | - Shu-Sheng Bao
- Beijing Key Laboratory for Biomaterials and Neural Regeneration, Beijing Advanced Innovation Center for Biomedical Engineering, School of Biological Science and Medical Engineering, Beihang University, Beijing, China
| | - Meng Xu
- Department of Orthopedics, The First Medical Center of PLA General Hospital, Beijing, China
| | - Jia-Sheng Rao
- Beijing Key Laboratory for Biomaterials and Neural Regeneration, Beijing Advanced Innovation Center for Biomedical Engineering, School of Biological Science and Medical Engineering, Beihang University, Beijing, China
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Balasubramanian N, Sagarkar S, Choudhary AG, Kokare DM, Sakharkar AJ. Epigenetic Blockade of Hippocampal SOD2 Via DNMT3b-Mediated DNA Methylation: Implications in Mild Traumatic Brain Injury-Induced Persistent Oxidative Damage. Mol Neurobiol 2021; 58:1162-1184. [PMID: 33099744 DOI: 10.1007/s12035-020-02166-z] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2020] [Accepted: 10/09/2020] [Indexed: 12/22/2022]
Abstract
The recurrent events of mild trauma exacerbate the vulnerability for post-traumatic stress disorder; however, the underlying molecular mechanisms are scarcely known. The repeated mild traumatic brain injury (rMTBI) perturbs redox homeostasis which is primarily managed by superoxide dismutase 2 (SOD2). The current study investigates the role of DNA methylation in SOD2 gene regulation and its involvement in rMTBI-induced persistent neuropathology inflicted by weight drop injury paradigm. The oxidative damage, neurodegenerative indicators, and SOD2 function and its regulation in the hippocampus were analyzed after 48 h and 30 days of rMTBI. The temporal and episodic increase in ROS levels (oxidative stress) heightened 8-hydroxyguanosine levels indicating oxidative damage after rMTBI that was concomitant with decline in SOD2 function. In parallel, occupancy of DNMT3b at SOD2 promoter was higher post 30 days of the first episode of rMTBI causing hypermethylation at SOD2 promoter. This epigenetic silencing of SOD2 promoter was sustained after the second episode of rMTBI causing permanent blockade in SOD2 response. The resultant oxidative stress further culminated into the increasing number of degenerating neurons. The treatment with 5-azacytidine, a pan DNMT inhibitor, normalized DNA methylation levels and revived SOD2 function after the second episode of rMTBI. The release of blockade in SOD2 expression by DNMT inhibition also normalized the post-traumatic oxidative consequences and relieved the neurodegeneration and deficits in learning and memory as measured by novel object recognition test. In conclusion, DNMT3b-mediated DNA methylation plays a critical role in SOD2 gene regulation in the hippocampus, and the perturbations therein post rMTBI are detrimental to redox homeostasis manifesting into neurological consequences.
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Affiliation(s)
| | - Sneha Sagarkar
- Department of Biotechnology, Savitribai Phule Pune University, Pune, 411 007, India
- Department of Zoology, Savitribai Phule Pune University, Pune, 411 007, India
| | - Amit G Choudhary
- Department of Pharmaceutical Sciences, Rashtrasant Tukadoji Maharaj Nagpur University, Nagpur, 440 033, India
| | - Dadasaheb M Kokare
- Department of Pharmaceutical Sciences, Rashtrasant Tukadoji Maharaj Nagpur University, Nagpur, 440 033, India
| | - Amul J Sakharkar
- Department of Biotechnology, Savitribai Phule Pune University, Pune, 411 007, India.
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Albayram O, Albayram S, Mannix R. Chronic traumatic encephalopathy-a blueprint for the bridge between neurological and psychiatric disorders. Transl Psychiatry 2020; 10:424. [PMID: 33293571 PMCID: PMC7723988 DOI: 10.1038/s41398-020-01111-x] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/18/2020] [Revised: 10/21/2020] [Accepted: 11/09/2020] [Indexed: 12/14/2022] Open
Abstract
Chronic traumatic encephalopathy (CTE) is a perplexing condition characterized by a broad and diverse range of neuropathology and psychopathology. While there are no agreed upon or validated clinical criteria for CTE, case series of CTE have described a wide range of neuropsychiatric symptoms that have been attributed to repetitive traumatic brain injuries (rTBI). However, the direct links between the psychopathology of psychiatric and neurological conditions from rTBI to CTE remains poorly understood. Prior studies suggest that repetitive cerebral injuries are associated with damage to neural circuitry involved in emotional and memory processes, but these studies do not offer longitudinal assessments that prove causation. More recent studies on novel targets, such as transmission of misfolded proteins, as well as newly advanced non-invasive imaging techniques may offer more direct evidence of the pathogenesis of CTE by tracing the progression of pathology and display of related behavioral impairments. Understanding this interface in the context of rTBI can play an important role in future approaches to the definition, assessment, prevention, and treatment of CTE and mental illnesses.
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Affiliation(s)
- Onder Albayram
- Division of Cardiology, Department of Medicine, Medical University of South Carolina, Charleston, SC, 29425, USA.
- Department of Neuroscience, Medical University of South Carolina, Charleston, SC, 29425, USA.
| | - Sait Albayram
- Department of Radiology, University of Florida College of Medicine, Gainesville, FL, 32610, USA
| | - Rebekkah Mannix
- Division of Emergency Medicine, Boston Children's Hospital, Harvard Medical School, Boston, MA, 02115, USA
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Li T, Hu E, Li P, Yang Z, Wu Y, Ding R, Zhu X, Tang T, Wang Y. Metabolomics Deciphers Potential Targets of Xuefu Zhuyu Decoction Against Traumatic Brain Injury in Rat. Front Pharmacol 2020; 11:559618. [PMID: 33101022 PMCID: PMC7546399 DOI: 10.3389/fphar.2020.559618] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2020] [Accepted: 09/07/2020] [Indexed: 12/25/2022] Open
Abstract
Xuefu Zhuyu decoction (XFZYD) performs multiple functions for traumatic brain injury (TBI) treatment. However, its clinical application is limited by the incomplete exploration of targets and inadequate discussion of mechanisms. We aimed to investigate the metabolic alterations of XFZYD in acute and chronic stages of TBI. Sprague-Dawley rats were randomly divided into the sham, controlled cortical impact (CCI) and XFZYD group. Behavioral and histopathological tests were used to evaluate the neuroprotective effects. Coagulation assays were performed to assess safety. Moreover, we analyzed the metabolomic profiling of hippocampal samples with different time intervals after CCI by high-performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS). Differential metabolites were screened by multivariate data analysis. To further uncover the association between candidate metabolites and biological interaction networks, we applied bioinformatics analysis using MetaboAnalyst 4.0, STITCH 5.0 and TCMSP. The potential mechanism was verified by ELISA and Western blot. XFZYD ameliorated neurological deficiencies post-CCI without impairing blood coagulation in the rat’s model. Seventeen and fourteen metabolites were filtered on d 3 and 21, respectively. Eleven of potential metabolites were common at these time points, involving two significant pathways (arginine and proline metabolism, phenylalanine, tyrosine and tryptophan biosynthesis). Gamma-aminobutyric acid (GABA) and the related pathways were specifically affected by XFZYD at the acute phase of TBI, while biosynthesis of amino acids was the major pathway influenced at the chronic phase. This study provides broad insights into the therapeutic effects of XFZYD in treating TBI through the whole phases.
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Affiliation(s)
- Teng Li
- Department of Integrated Traditional Chinese and Western Medicine, Institute of Integrative Medicine, Xiangya Hospital, Central South University, Changsha, China
| | - En Hu
- Department of Integrated Traditional Chinese and Western Medicine, Institute of Integrative Medicine, Xiangya Hospital, Central South University, Changsha, China
| | - Pengfei Li
- Department of Respiratory and Critical Care Medicine, The First Affiliated Hospital, Zhengzhou University, Zhengzhou, China
| | - Zhaoyu Yang
- Department of Integrated Traditional Chinese and Western Medicine, Institute of Integrative Medicine, Xiangya Hospital, Central South University, Changsha, China
| | - Yao Wu
- Department of Integrated Traditional Chinese and Western Medicine, Institute of Integrative Medicine, Xiangya Hospital, Central South University, Changsha, China
| | - Ruoqi Ding
- Department of Integrated Traditional Chinese and Western Medicine, Institute of Integrative Medicine, Xiangya Hospital, Central South University, Changsha, China
| | - Xiaofei Zhu
- Department of Integrated Traditional Chinese and Western Medicine, Institute of Integrative Medicine, Xiangya Hospital, Central South University, Changsha, China
| | - Tao Tang
- Department of Integrated Traditional Chinese and Western Medicine, Institute of Integrative Medicine, Xiangya Hospital, Central South University, Changsha, China
| | - Yang Wang
- Department of Integrated Traditional Chinese and Western Medicine, Institute of Integrative Medicine, Xiangya Hospital, Central South University, Changsha, China
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11
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León-Moreno LC, Castañeda-Arellano R, Aguilar-García IG, Desentis-Desentis MF, Torres-Anguiano E, Gutiérrez-Almeida CE, Najar-Acosta LJ, Mendizabal-Ruiz G, Ascencio-Piña CR, Dueñas-Jiménez JM, Rivas-Carrillo JD, Dueñas-Jiménez SH. Kinematic Changes in a Mouse Model of Penetrating Hippocampal Injury and Their Recovery After Intranasal Administration of Endometrial Mesenchymal Stem Cell-Derived Extracellular Vesicles. Front Cell Neurosci 2020; 14:579162. [PMID: 33192324 PMCID: PMC7533596 DOI: 10.3389/fncel.2020.579162] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2020] [Accepted: 08/14/2020] [Indexed: 12/20/2022] Open
Abstract
Locomotion speed changes appear following hippocampal injury. We used a hippocampal penetrating brain injury mouse model to analyze other kinematic changes. We found a significant decrease in locomotion speed in both open-field and tunnel walk tests. We described a new quantitative method that allows us to analyze and compare the displacement curves between mice steps. In the tunnel walk, we marked mice with indelible ink on the knee, ankle, and metatarsus of the left and right hindlimbs to evaluate both in every step. Animals with hippocampal damage exhibit slower locomotion speed in both hindlimbs. In contrast, in the cortical injured group, we observed significant speed decrease only in the right hindlimb. We found changes in the displacement patterns after hippocampal injury. Mesenchymal stem cell-derived extracellular vesicles had been used for the treatment of several diseases in animal models. Here, we evaluated the effects of intranasal administration of endometrial mesenchymal stem cell-derived extracellular vesicles on the outcome after the hippocampal injury. We report the presence of vascular endothelial growth factor, granulocyte–macrophage colony-stimulating factor, and interleukin 6 in these vesicles. We observed locomotion speed and displacement pattern preservation in mice after vesicle treatment. These mice had lower pyknotic cells percentage and a smaller damaged area in comparison with the nontreated group, probably due to angiogenesis, wound repair, and inflammation decrease. Our results build up on the evidence of the hippocampal role in walk control and suggest that the extracellular vesicles could confer neuroprotection to the damaged hippocampus.
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Affiliation(s)
- Lilia Carolina León-Moreno
- Laboratory of Neurophysiology, Department of Neuroscience, University Center for Health Sciences, University of Guadalajara, Guadalajara, Mexico.,Department of Biomedical Sciences, University Center of Tonala, University of Guadalajara, Guadalajara, Mexico
| | - Rolando Castañeda-Arellano
- Laboratory of Tissue Engineering and Transplant, Department of Physiology, cGMP Cell Processing Facility, University Center for Health Sciences, University of Guadalajara, Guadalajara, Mexico
| | - Irene Guadalupe Aguilar-García
- Laboratory of Neurophysiology, Department of Neuroscience, University Center for Health Sciences, University of Guadalajara, Guadalajara, Mexico
| | | | - Elizabeth Torres-Anguiano
- Department of Biomedical Sciences, University Center of Tonala, University of Guadalajara, Guadalajara, Mexico
| | - Coral Estefanía Gutiérrez-Almeida
- Laboratory of Neurophysiology, Department of Neuroscience, University Center for Health Sciences, University of Guadalajara, Guadalajara, Mexico
| | - Luis Jesús Najar-Acosta
- Department of Biomedical Sciences, University Center of Tonala, University of Guadalajara, Guadalajara, Mexico
| | - Gerardo Mendizabal-Ruiz
- Department of Computer Sciences, University Center of Exact Sciences and Engineering, University of Guadalajara, Guadalajara, Mexico
| | - César Rodolfo Ascencio-Piña
- Department of Computer Sciences, University Center of Exact Sciences and Engineering, University of Guadalajara, Guadalajara, Mexico
| | - Judith Marcela Dueñas-Jiménez
- Laboratory of Neurophysiology, Department of Neuroscience, University Center for Health Sciences, University of Guadalajara, Guadalajara, Mexico
| | - Jorge David Rivas-Carrillo
- Department of Biomedical Sciences, University Center of Tonala, University of Guadalajara, Guadalajara, Mexico
| | - Sergio Horacio Dueñas-Jiménez
- Laboratory of Neurophysiology, Department of Neuroscience, University Center for Health Sciences, University of Guadalajara, Guadalajara, Mexico
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12
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The treatment of Goji berry (Lycium barbarum) improves the neuroplasticity of the prefrontal cortex and hippocampus in aged rats. J Nutr Biochem 2020; 83:108416. [DOI: 10.1016/j.jnutbio.2020.108416] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2019] [Revised: 03/06/2020] [Accepted: 05/02/2020] [Indexed: 12/17/2022]
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13
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Schumm SN, Gabrieli D, Meaney DF. Neuronal Degeneration Impairs Rhythms Between Connected Microcircuits. Front Comput Neurosci 2020; 14:18. [PMID: 32194390 PMCID: PMC7063469 DOI: 10.3389/fncom.2020.00018] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2019] [Accepted: 02/11/2020] [Indexed: 11/23/2022] Open
Abstract
Synchronization of neural activity across brain regions is critical to processes that include perception, learning, and memory. After traumatic brain injury (TBI), neuronal degeneration is one possible effect and can alter communication between neural circuits. Consequently, synchronization between neurons may change and can contribute to both lasting changes in functional brain networks and cognitive impairment in patients. However, fundamental principles relating exactly how TBI at the cellular scale affects synchronization of mesoscale circuits are not well understood. In this work, we use computational networks of Izhikevich integrate-and-fire neurons to study synchronized, oscillatory activity between clusters of neurons, which also adapt according to spike-timing-dependent plasticity (STDP). We study how the connections within and between these neuronal clusters change as unidirectional connections form between the two neuronal populations. In turn, we examine how neuronal deletion, intended to mimic the temporary or permanent loss of neurons in the mesoscale circuit, affects these dynamics. We determine synchronization of two neuronal circuits requires very modest connectivity between these populations; approximately 10% of neurons projecting from one circuit to another circuit will result in high synchronization. In addition, we find that synchronization level inversely affects the strength of connection between neuronal microcircuits - moderately synchronized microcircuits develop stronger intercluster connections than do highly synchronized circuits. Finally, we find that highly synchronized circuits are largely protected against the effects of neuronal deletion but may display changes in frequency properties across circuits with targeted neuronal loss. Together, our results suggest that strongly and weakly connected regions differ in their inherent resilience to damage and may serve different roles in a larger network.
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Affiliation(s)
- Samantha N. Schumm
- Department of Bioengineering, School of Engineering and Applied Sciences, University of Pennsylvania, Philadelphia, PA, United States
| | - David Gabrieli
- Department of Bioengineering, School of Engineering and Applied Sciences, University of Pennsylvania, Philadelphia, PA, United States
| | - David F. Meaney
- Department of Bioengineering, School of Engineering and Applied Sciences, University of Pennsylvania, Philadelphia, PA, United States
- Penn Center for Brain Injury and Repair, Department of Neurosurgery, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, United States
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14
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Sagarkar S, Balasubramanian N, Mishra S, Choudhary AG, Kokare DM, Sakharkar AJ. Repeated mild traumatic brain injury causes persistent changes in histone deacetylase function in hippocampus: Implications in learning and memory deficits in rats. Brain Res 2019; 1711:183-192. [DOI: 10.1016/j.brainres.2019.01.022] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2018] [Revised: 01/16/2019] [Accepted: 01/17/2019] [Indexed: 12/25/2022]
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15
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Hansen KR, DeWalt GJ, Mohammed AI, Tseng HA, Abdulkerim ME, Bensussen S, Saligrama V, Nazer B, Eldred WD, Han X. Mild Blast Injury Produces Acute Changes in Basal Intracellular Calcium Levels and Activity Patterns in Mouse Hippocampal Neurons. J Neurotrauma 2018; 35:1523-1536. [PMID: 29343209 PMCID: PMC5998839 DOI: 10.1089/neu.2017.5029] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Mild traumatic brain injury (mTBI) represents a serious public health concern. Although much is understood about long-term changes in cell signaling and anatomical pathologies associated with mTBI, little is known about acute changes in neuronal function. Using large scale Ca2+ imaging in vivo, we characterized the intracellular Ca2+ dynamics in thousands of individual hippocampal neurons using a repetitive mild blast injury model in which blasts were directed onto the cranium of unanesthetized mice on two consecutive days. Immediately following each blast event, neurons exhibited two types of changes in Ca2+ dynamics at different time scales. One was a reduction in slow Ca2+ dynamics that corresponded to shifts in basal intracellular Ca2+ levels at a time scale of minutes, suggesting a disruption of biochemical signaling. The second was a reduction in the rates of fast transient Ca2+ fluctuations at the sub-second time scale, which are known to be closely linked to neural activity. Interestingly, the blast-induced changes in basal Ca2+ levels were independent of the changes in the rates of fast Ca2+ transients, suggesting that blasts had heterogeneous effects on different cell populations. Both types of changes recovered after ∼1 h. Together, our results demonstrate that mTBI induced acute, heterogeneous changes in neuronal function, altering intracellular Ca2+ dynamics across different time scales, which may contribute to the initiation of longer-term pathologies.
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Affiliation(s)
- Kyle R. Hansen
- Department of Biomedical Engineering, Boston University, Boston, Massachusetts
| | | | - Ali I. Mohammed
- Department of Biomedical Engineering, Boston University, Boston, Massachusetts
| | - Hua-an Tseng
- Department of Biomedical Engineering, Boston University, Boston, Massachusetts
| | - Moona E. Abdulkerim
- Department of Biomedical Engineering, Boston University, Boston, Massachusetts
| | - Seth Bensussen
- Department of Biomedical Engineering, Boston University, Boston, Massachusetts
| | - Venkatesh Saligrama
- Department of Electrical and Computer Engineering, Boston University, Boston, Massachusetts
| | - Bobak Nazer
- Department of Electrical and Computer Engineering, Boston University, Boston, Massachusetts
| | | | - Xue Han
- Department of Biomedical Engineering, Boston University, Boston, Massachusetts
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16
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Hayes JP, Reagan A, Logue MW, Hayes SM, Sadeh N, Miller DR, Verfaellie M, Wolf EJ, McGlinchey RE, Milberg WP, Stone A, Schichman SA, Miller MW. BDNF genotype is associated with hippocampal volume in mild traumatic brain injury. GENES BRAIN AND BEHAVIOR 2017; 17:107-117. [PMID: 28755387 DOI: 10.1111/gbb.12403] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/10/2017] [Revised: 07/01/2017] [Accepted: 07/23/2017] [Indexed: 12/14/2022]
Abstract
The negative long-term effects of mild traumatic brain injury (mTBI) have been a growing concern in recent years, with accumulating evidence suggesting that mTBI combined with additional vulnerability factors may induce neurodegenerative-type changes in the brain. However, the factors instantiating risk for neurodegenerative disease following mTBI are unknown. This study examined the link between mTBI and brain-derived neurotrophic factor (BDNF) genotype, which has previously been shown to regulate processes involved in neurodegeneration including synaptic plasticity and facilitation of neural survival through its expression. Specifically, we examined nine BDNF single-nucleotide polymorphisms (SNPs; rs908867, rs11030094, rs6265, rs10501087, rs1157659, rs1491850, rs11030107, rs7127507 and rs12273363) previously associated with brain atrophy or memory deficits in mTBI. Participants were 165 white, non-Hispanic Iraq and Afghanistan war veterans between the ages of 19 and 58, 110 of whom had at least one mTBI in their lifetime. Results showed that the BDNF SNP rs1157659 interacted with mTBI to predict hippocampal volume. Furthermore, exploratory analysis of functional resting state data showed that rs1157659 minor allele homozygotes with a history of mTBI had reduced functional connectivity in the default mode network compared to major allele homozygotes and heterozygotes. Apolipoprotein E (APOE) was not a significant predictor of hippocampal volume or functional connectivity. These results suggest that rs1157659 minor allele homozygotes may be at greater risk for neurodegeneration after exposure to mTBI and provide further evidence for a potential role for BDNF in regulating neural processes following mTBI.
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Affiliation(s)
- J P Hayes
- National Center for PTSD, VA Boston Healthcare System, Boston, MA, USA.,Department of Psychiatry, Boston University School of Medicine, Boston, MA, USA.,Neuroimaging Research for Veterans Center, VA Boston Healthcare System, Boston, MA, USA
| | - A Reagan
- National Center for PTSD, VA Boston Healthcare System, Boston, MA, USA
| | - M W Logue
- National Center for PTSD, VA Boston Healthcare System, Boston, MA, USA.,Biomedical Genetics, Boston University School of Medicine, Boston, MA, USA.,Department of Biostatistics, Boston University School of Public Health, Boston, MA, USA
| | - S M Hayes
- Department of Psychiatry, Boston University School of Medicine, Boston, MA, USA.,Neuroimaging Research for Veterans Center, VA Boston Healthcare System, Boston, MA, USA.,Memory Disorders Research Center, VA Boston Healthcare System, Boston, MA, USA
| | - N Sadeh
- National Center for PTSD, VA Boston Healthcare System, Boston, MA, USA.,Department of Psychological and Brain Studies, University of Delaware, Newark, DE, USA
| | - D R Miller
- National Center for PTSD, VA Boston Healthcare System, Boston, MA, USA.,Department of Psychiatry, Boston University School of Medicine, Boston, MA, USA
| | - M Verfaellie
- Department of Psychiatry, Boston University School of Medicine, Boston, MA, USA.,Memory Disorders Research Center, VA Boston Healthcare System, Boston, MA, USA
| | - E J Wolf
- National Center for PTSD, VA Boston Healthcare System, Boston, MA, USA.,Department of Psychiatry, Boston University School of Medicine, Boston, MA, USA
| | - R E McGlinchey
- Geriatric Research, Educational and Clinical Center and Translational Research Center for TBI and Stress Disorders, VA Boston Healthcare System, Boston, MA, USA.,Department of Psychiatry, Harvard Medical School, Boston, MA, USA
| | - W P Milberg
- Geriatric Research, Educational and Clinical Center and Translational Research Center for TBI and Stress Disorders, VA Boston Healthcare System, Boston, MA, USA.,Department of Psychiatry, Harvard Medical School, Boston, MA, USA
| | - A Stone
- Pharmacogenomics Analysis Laboratory, Research Service, Central Arkansas Veterans Healthcare System, Little Rock, AR, USA
| | - S A Schichman
- Pharmacogenomics Analysis Laboratory, Research Service, Central Arkansas Veterans Healthcare System, Little Rock, AR, USA
| | - M W Miller
- National Center for PTSD, VA Boston Healthcare System, Boston, MA, USA.,Department of Psychiatry, Boston University School of Medicine, Boston, MA, USA
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