Long-term psychiatric disorders after traumatic brain injury:

Trauma's distinctive and combined effects on subsequent substance use, mental health, and neurocognitive functioning with the NCANDA sample

PURPOSE

Traumatic brain injury (TBI) and potentially traumatic events (PTEs) contribute to increased substance use, mental health issues, and cognitive impairments. However, there's not enough research on how TBI and PTEs combined impact mental heath, substance use, and neurocognition.

METHODS

This study leverages a subset of The National Consortium on Alcohol and Neurodevelopment in Adolescence (NCANDA) multi-site dataset with 551 adolescents to assess the combined and distinctive impacts of TBI, PTEs, and TBI+PTEs (prior to age 18) on substance use, mental health, and neurocognitive outcomes at age 18.

RESULTS

TBI, PTEs, and TBI+PTEs predicted greater lifetime substance use and past-year alcohol and cannabis use. PTEs predicted greater internalizing symptoms, while TBI+PTEs predicted greater externalizing symptoms. Varying effects on neurocognitive outcomes included PTEs influencing attention accuracy and TBI+PTEs predicting faster speed in emotion tasks. PTEs predicted greater accuracy in abstraction-related tasks. Associations with working memory were not detected.

CONCLUSION

This exploratory study contributes to the growing literature on the complex interplay between TBI, PTEs, and adolescent mental health, substance use, and neurocognition. The developmental implications of trauma via TBIs and/or PTEs during adolescence are considerable and worthy of further investigation.

Dizziness Directly Influences Postconcussion Symptoms and Is Predictive of Poorer Mental Health in UK Military Personnel: A Retrospective Analysis

OBJECTIVE

To investigate the contribution of dizziness to postconcussion symptoms, depression, and anxiety symptoms.

SETTING

Mild traumatic brain injury (mTBI) service, Defence Medical Rehabilitation Centre, Stanford Hall.

PARTICIPANTS

Two hundred eighty-three UK military personnel from the Royal Navy, Royal Airforce, Royal Marines, and British Army.

DESIGN

A retrospective analysis of data from the Ministry of Defence medical records database.

MAIN MEASURES

Sixteen-item Rivermead Post Concussion Symptoms Questionnaire, Generalized Anxiety Disorder 7-item scale, Patient Health Questionnaire-9, The Dizziness Handicap Inventory.

RESULTS

Injuries from sports or falls were the most common mechanism of mTBI, accounting for 23%, respectively. Chi-square analysis indicated that individuals with dizziness and postconcussion symptoms (PCS) had greater severity of PCS, depression, and anxiety than those with PCS alone. Mediation analysis showed dizziness directly and independently influenced the severity of PCS, despite the indirect effects of mediating depression and anxiety symptoms.

CONCLUSION

Comorbid dizziness and PCS were predictive of poorer mental health compared with PCS alone. In addition, dizziness directly influenced the severity of PCS irrespective of the indirect effects of mental health symptoms. These observations suggest that treating dizziness with vestibular rehabilitation may improve PCS and mental health.

Traumatic Brain Injury Outcomes After Recreational Cannabis Use

Purpose

Basic science data indicate potential neuroprotective effects of cannabinoids in traumatic brain injury (TBI). We aimed to evaluate the effects of pre-TBI recreational cannabis use on TBI outcomes.

Patients and Methods

We used i2b2 (a scalable informatics framework; www.i2b2.org) to identify all patients presenting with acute TBI between 1/1/2014 and 12/31/2016, then conducted a double-abstraction medical chart review to compile basic demographic, urine drug screen (UDS), Glasgow Coma Scale (GCS), and available outcomes data (mortality, modified Rankin Scale (mRS), duration of stay, disposition (home, skilled nursing facility, inpatient rehabilitation, other)) at discharge and at specific time points thereafter. We conducted multivariable nested ordinal and logistic regression analyses to estimate associations between cannabis use, other UDS results, demographic factors, and selected outcomes.

Results

i2b2 identified 6396 patients who acutely presented to our emergency room with TBI. Of those, 3729 received UDS, with 22.2% of them testing positive for cannabis. Mortality was similar in patients who tested positive vs negative for cannabis (3.9% vs 4.8%; p = 0.3) despite more severe GCS on admission in the cannabis positive group (p = 0.045). Several discharge outcome measures favored the cannabis positive group who had a higher rate of discharge home vs other care settings (p < 0.001), lower discharge mRS (p < 0.001), and shorter duration of hospital stay (p < 0.001) than the UDS negative group. Multivariable analyses confirmed mostly independent associations between positive cannabis screen and these post-TBI short- and long-term outcomes.

Conclusion

This study adds evidence about the potentially neuroprotective effects of recreational cannabis for short- and long-term post-TBI outcomes. These results need to be confirmed via prospective data collections.

Cognitive impairment in Chinese traumatic brain injury patients: from challenge to future perspectives

Traumatic Brain Injury (TBI) is a prevalent form of neurological damage that may induce varying degrees of cognitive dysfunction in patients, consequently impacting their quality of life and social functioning. This article provides a mini review of the epidemiology in Chinese TBI patients and etiology of cognitive impairment. It analyzes the risk factors of cognitive impairment, discusses current management strategies for cognitive dysfunction in Chinese TBI patients, and summarizes the strengths and limitations of primary testing tools for TBI-related cognitive functions. Furthermore, the article offers a prospective analysis of future challenges and opportunities. Its objective is to contribute as a reference for the prevention and management of cognitive dysfunction in Chinese TBI patients.

Putting the Ducks in a Row: Development of a Duck-assisted Green Care Intervention for Persons with Traumatic Brain Injury

Green Care therapies are defined as the engagement of a patient with the nature, exposing patients to a nature based therapeutic setting that may facilitate their recovery. Such therapies became popular at the end of the twentieth century. This therapeutic approach may include therapeutic horticulture, nature therapies, care farming, facilitated exercise, and animal-assisted therapies with farm animals (AATF). This paper describes the processes of planning and creating an AATF-based clinical intervention wherein persons with TBI interacted with ducks (in twice weekly, 1-hour groups) for 12 wk at a TBI rehabilitation facility. The discussion includes site identification, stakeholder engagement, intervention design and human and animal safety procedures. The research methods, theoretical framework, ethical consideration, and risk reduction strategies for human participants and ducks are discussed. Also, description of challenges and blueprints of possible solutions for other researchers interested in developing similar initiatives. This program will serve as a study site for examining effects of AATF-based interventions on self-efficacy, depression, and anxiety in persons with TBI. If the study suggests that AATF interventions with ducks may lead to positive changes, the proposed study will be followed with studies that include larger samples at multiple sites. Findings in this paper may contribute to the implementation science body of knowledge. Because of that, the information in this paper may benefit the researchers outside of the healthcare arena. From that perspective methods described in this paper may help to develop studies that focus on policy development, program expansion, or individual project implementation.

Impaired cortical neuronal homeostasis and cognition after diffuse traumatic brain injury are dependent on microglia and type I interferon responses

Neuropsychiatric complications including depression and cognitive decline develop in the years after traumatic brain injury (TBI), negatively affecting quality of life. Microglial and type 1 interferon (IFN-I) responses are associated with the transition from acute to chronic neuroinflammation after diffuse TBI in mice. Thus, the purpose of this study was to determine if impaired neuronal homeostasis and increased IFN-I responses intersected after TBI to cause cognitive impairment. Here, the RNA profile of neurons and microglia after TBI (single nucleus RNA-sequencing) with or without microglia depletion (CSF1R antagonist) was assessed 7 dpi. There was a TBI-dependent suppression of cortical neuronal homeostasis with reductions in CREB signaling, synaptogenesis, and synaptic migration and increases in RhoGDI and PTEN signaling (Ingenuity Pathway Analysis). Microglial depletion reversed 50% of TBI-induced gene changes in cortical neurons depending on subtype. Moreover, the microglial RNA signature 7 dpi was associated with increased stimulator of interferon genes (STING) activation and IFN-I responses. Therefore, we sought to reduce IFN-I signaling after TBI using STING knockout mice and a STING antagonist, chloroquine (CQ). TBI-associated cognitive deficits in novel object location and recognition (NOL/NOR) tasks at 7 and 30 dpi were STING dependent. In addition, TBI-induced STING expression, microglial morphological restructuring, inflammatory (Tnf, Cd68, Ccl2) and IFN-related (Irf3, Irf7, Ifi27) gene expression in the cortex were attenuated in STINGKO mice. CQ also reversed TBI-induced cognitive deficits and reduced TBI-induced inflammatory (Tnf, Cd68, Ccl2) and IFN (Irf7, Sting) cortical gene expression. Collectively, reducing IFN-I signaling after TBI with STING-dependent interventions attenuated the prolonged microglial activation and cognitive impairment.

Pediatric traumatic brain injury as a risk factor for psychosis and psychotic symptoms: a systematic review and meta-analysis

BACKGROUND

Psychosis is one of the most disabling psychiatric disorders. Pediatric traumatic brain injury (pTBI) has been cited as a developmental risk factor for psychosis, however this association has never been assessed meta-analytically.

METHODS

A systematic review and meta-analysis of the association between pTBI and subsequent psychotic disorders/symptoms was performed. The study was pre-registered (CRD42022360772) adopting a random-effects model to estimate meta-analytic odds ratio (OR) and 95% confidence interval (CI) using the Paule-Mandel estimator. Subgroup (study location, study design, psychotic disorder v. subthreshold symptoms, assessment type, and adult v. adolescent onset) and meta-regression (quality of evidence) analyses were also performed. The robustness of findings was assessed through sensitivity analyses. The meta-analysis is available online as a computational notebook with an open dataset.

RESULTS

We identified 10 relevant studies and eight were included in the meta-analysis. Based on a pooled sample size of 479686, the pooled OR for the association between pTBI and psychosis outcomes was 1.80 (95% CI 1.11-2.95). There were no subgroup effects and no outliers. Both psychotic disorder and subthreshold symptoms were associated with pTBI. The overall association remained robust after removal of low-quality studies, however the OR reduced to 1.43 (95% CI 1.04-1.98). A leave-one-out sensitivity analysis showed the association was robust to removal of all but one study which changed the estimate to marginally non-significant.

CONCLUSIONS

We report cautious meta-analytic evidence for a positive association between pTBI and future psychosis. New evidence will be key in determining long-term reliability of this finding.

Microglia moonlighting after traumatic brain injury: aging and interferons influence chronic microglia reactivity

Most of the individuals who experience traumatic brain injury (TBI) develop neuropsychiatric and cognitive complications that negatively affect recovery and health span. Activation of multiple inflammatory pathways persists after TBI, but it is unclear how inflammation contributes to long-term behavioral and cognitive deficits. One outcome of TBI is microglial priming and subsequent hyper-reactivity to secondary stressors, injuries, or immune challenges that further augment complications. Additionally, microglia priming with aging contributes to exaggerated glial responses to TBI. One prominent inflammatory pathway, interferon (IFN) signaling, is increased after TBI and may contribute to microglial priming and subsequent reactivity. This review discusses the contributions of microglia to inflammatory processes after TBI, as well as the influence of aging and IFNs on microglia reactivity and chronic inflammation after TBI.

Repeatability of neurite orientation dispersion and density imaging in patients with traumatic brain injury

BACKGROUND AND PURPOSE

The aim of this study was to assess the repeatability of neurite orientation dispersion and density imaging in healthy controls (HCs) and traumatic brain injury (TBI).

METHODS

Seventeen HCs and 48 TBI patients were scanned twice over 18 weeks with diffusion imaging. Orientation dispersion (ODI), neurite density (NDI), and the fraction of isotropic diffusion (F-ISO) were quantified in regions of interest (ROIs) from a gray matter, subcortical, and white matter atlas and compared using the coefficient of variation for repeated measures (CVrep ), which quantifies the expected percent change on repeated measurement. We used a modified signed likelihood ratio test (M-SLRT) to compare the CVrep between groups in each ROI while correcting for multiple comparisons.

RESULTS

NDI exhibited excellent repeatability in both groups; the only group difference was found in the fusiform gyrus, where HCs exhibited better repeatability (M-SLRT = 9.463, p = .0021). ODI also had excellent repeatability in both groups, although repeatability was significantly better in HCs in 16 cortical ROIs (p < .0022) and in the bilateral white matter and bilateral cortex (p < .0027). F-ISO exhibited relatively poor repeatability in both groups, with few group differences.

CONCLUSION

Overall, the repeatability of the NDI, ODI, and F-ISO metrics over an 18-week period is acceptable for assessing the effects of behavioral or pharmacological interventions, though caution is advised when assessing F-ISO changes over time.

Risk of secondary stroke subsequent to restarting aspirin in chronic stroke patients suffering from traumatic brain injury in Taiwan

Traumatic brain injury (TBI) is a silent epidemic that has been easily ignored. The safety and efficacy of restarting antiplatelet therapy after encountering traumatic brain injury (TBI) events remain a challenge. We explored the outcomes of restarting aspirin use on secondary stroke and mortality in patients with chronic stroke 4 weeks after suffering from a TBI episode in Taiwan. This study analyzed data from the National Health Insurance Research Database from January 2000 to December 2015. Overall, 136,211 individuals diagnosed with chronic stroke who suffered from acute TBI and received inpatient service were enrolled. The study outcomes were a competing risk of secondary stroke (ischemic and hemorrhagic) hospitalization and all-cause mortality. We identified a case group of 15,035 patients with chronic stroke (mean [SD] age of 53.25 [19.74] years; 55.63% male) who restarted aspirin use 4 weeks after suffering from TBI and a control group of 60,140 patients with chronic stroke (mean [SD] age of 53.12 [19.22] years; 55.63% male) who discontinued aspirin use after suffering from TBI. The risk of hospitalization of secondary ischemic stroke [adjusted hazard ratio (aHR) 0.694; 95% confidence interval (CI) 0.621-0.756; P < 0.001] and hemorrhagic stroke (aHR 0.642; 95% CI 0.549-0.723; P < 0.001) and all-cause mortality (aHR 0.840; 95% CI 0.720-0.946; P < 0.001) significantly decreased in patients with chronic stroke restarting aspirin use 1 month after suffering from TBI events (including intracranial hemorrhage) in comparison with the control subjects, regardless of those with or without diabetes mellitus, chronic kidney disease, myocardial infarction, atrial fibrillation, clopidogrel use, and dipyridamole use. Restarting aspirin use could lower the risks of secondary stroke (ischemic and hemorrhagic) hospitalization and all-cause mortality in patients with chronic stroke 1 month after suffering from TBI episodes.

Systems spatiotemporal dynamics of traumatic brain injury at single-cell resolution reveals humanin as a therapeutic target

BACKGROUND

The etiology of mild traumatic brain injury (mTBI) remains elusive due to the tissue and cellular heterogeneity of the affected brain regions that underlie cognitive impairments and subsequent neurological disorders. This complexity is further exacerbated by disrupted circuits within and between cell populations across brain regions and the periphery, which occur at different timescales and in spatial domains.

METHODS

We profiled three tissues (hippocampus, frontal cortex, and blood leukocytes) at the acute (24-h) and subacute (7-day) phases of mTBI at single-cell resolution.

RESULTS

We demonstrated that the coordinated gene expression patterns across cell types were disrupted and re-organized by TBI at different timescales with distinct regional and cellular patterns. Gene expression-based network modeling implied astrocytes as a key regulator of the cell-cell coordination following mTBI in both hippocampus and frontal cortex across timepoints, and mt-Rnr2, which encodes the mitochondrial peptide humanin, as a potential target for intervention based on its broad regional and dynamic dysregulation following mTBI. Treatment of a murine mTBI model with humanin reversed cognitive impairment caused by mTBI through the restoration of metabolic pathways within astrocytes.

CONCLUSIONS

Our results offer a systems-level understanding of the dynamic and spatial regulation of gene programs by mTBI and pinpoint key target genes, pathways, and cell circuits that are amenable to therapeutics.

Neuroimaging Biomarkers of New-Onset Psychiatric Disorders Following Traumatic Brain Injury

Traumatic brain injury (TBI) has traditionally been associated with cognitive and behavioral changes during both the acute and chronic phases of injury. Because of its noninvasive nature, neuroimaging has the potential to provide unique information on underlying macroscopic and microscopic biological mechanisms that may serve as causative agents for these neuropsychiatric sequelae. This broad scoping review identifies at least 4 common macroscopic pathways that exist between TBI and new-onset psychiatric disorders, as well as several examples of how neuroimaging is currently being utilized in clinical research. The review then critically examines the strengths and limitations of neuroimaging for elucidating TBI-related microscopic pathology, such as microstructural changes, neuroinflammation, proteinopathies, blood-brain barrier damage, and disruptions in cellular signaling. A summary is then provided for how neuroimaging is currently being used to investigate TBI-related pathology in new-onset neurocognitive disorders, depression, and posttraumatic stress disorder. Identified gaps in the literature include a lack of prospective studies to definitively associate imaging findings with the development of new-onset psychiatric disorders, as well as antemortem imaging studies subsequently confirmed with postmortem correlates in the same study cohort. Although the spatial resolution and specificity of imaging biomarkers has greatly improved over the last 2 decades, we conclude that neuroimaging biomarkers do not yet exist for the definitive in vivo diagnosis of cellular pathology. This represents a necessary next step for further elucidating causal relationships between TBI and new-onset psychiatric disorders.

Forensic psychiatric analysis of organic personality disorders after craniocerebral injury in Shanghai, China

OBJECTIVE

To explore the incidence rate and the differences of clinical manifestations of organic personality disorders with varying degrees of craniocerebral trauma.

MATERIALS AND METHODS

According to the International Classification of Diseases-10, 1,027 subjects with craniocerebral trauma caused by traffic accidents were reviewed, the degrees of craniocerebral trauma were graded and those with personality disorder after craniocerebral trauma were diagnosed. The personality characteristics of all patients were evaluated by using the simplified Neuroticism Extraversion Openness Five-Factor Inventory (NEO-FFI).

RESULTS

The incidence rate of organic personality disorder after all kinds of craniocerebral trauma was 33.1%, while it was 38.7 and 44.2% in the patients after moderate and severe craniocerebral trauma, respectively, which was significantly higher than that in the patients after mild craniocerebral trauma (18.0%) (P < 0.05). Compared with the patients without personality disorder, the neuroticism, extraversion and agreeableness scores all showed significantly differences (P < 0.05) in the patients with personality disorder after craniocerebral trauma; especially the conscientiousness scores showed significant differences (P < 0.05) in the patients with personality disorder after moderate and severe craniocerebral trauma. The agreeableness and conscientiousness scores in the patients with personality disorder after moderate and severe craniocerebral trauma were significantly lower than that after mild craniocerebral trauma, and the patients with personality disorder after severe craniocerebral trauma had lower scores in extraversion than that after mild craniocerebral trauma.

CONCLUSION

The severity and area of craniocerebral trauma is closely related to the incidence rate of organic personality disorder, and it also affects the clinical manifestations of the latter, which provides a certain significance and help for forensic psychiatric appraisal.

Personality changes after acquired brain injury and their effects on rehabilitation outcomes

Acquired brain injury (ABI) is often associated with personality changes. Pre- as well as post-injury personality traits are related to rehabilitation outcomes. However, it largely remains unclear whether post-injury personality shows any associations with rehabilitation outcomes over and above pre-injury personality. Using a case-control design, this study investigated (1) personality changes after ABI from patients' and significant others' perspective, and (2) relations of pre- and post-ABI personality traits to rehabilitation outcomes in the short- and long-term. 40 patients with ABI (85% stroke, 15% traumatic brain injury), 46 healthy controls and their significant others participated. Personality was assessed with NEO-FFI, rehabilitation outcomes (activities, participation, depression) were measured at two and ten months after ABI. Patient-ratings indicated decreases in extraversion and a trend towards reduced conscientiousness. Significant others reported increases in patients' neuroticism. Pre- as well as post-injury personality traits were associated with depression and activities at both short- and long-term timepoints after ABI. The association was strongest for long-term depressive symptoms where personality trait variables accounted for 49% of variance (Radjusted2). Our results confirm that ABI patients and significant others perceive personality changes, albeit in different dimensions. Pre- and post-ABI personality traits showed associations with rehabilitation outcomes, especially with emotional adjustment after the injury.

Regenerative medicine and traumatic brain injury: from stem cell to cell-free therapeutic strategies

Traumatic brain injury (TBI) is a serious health concern, yet there is a lack of standardized treatment to combat its long-lasting effects. The objective of the present study was to provide an overview of the limitation of conventional stem-cell therapy in the treatment of TBI and to discuss the application of novel acellular therapies and their advanced strategies to enhance the efficacy of stem cells derived therapies in the light of published study data. Moreover, we also discussed the factor to optimize the therapeutic efficiency of stem cell-derived acellular therapy by overcoming the challenges for its clinical translation. Hence, we concluded that acellular therapy possesses the potential to bring a breakthrough in the field of regenerative medicine to treat TBI.

Cranial nerve injuries in patients with moderate to severe head trauma - Analysis of 91,196 patients from the TraumaRegister DGU® between 2008 and 2017

OBJECTIVE

Traumatic brain injury (TBI) constitutes a major cause of trauma-related disability and mortality. The epidemiology and implications of associated cranial nerve injuries　(CNI)　in moderate to severe TBI are largely unknown. We aimed to determine the incidence of CNI in a large European cohort of TBI patients as well as clinical differences between TBI cases with and without concomitant CNI (CNI vs. control group) by means of a multinational trauma registry.

METHODS

The TraumaRegister DGU® was evaluated for trauma patients with head injuries ≥ 2 Abbreviated Injury Scale, who had to be treated on intensive care units after emergency admission to European hospitals between 2008 and 2017. CNI and control cases were compared with respect to demographic, clinical, and outcome variables.

RESULTS

1.0% (946 of 91,196) of TBI patients presented with additional CNI. On average, CNI patients were younger than control cases (44.3 ± 20.6 vs. 51.8 ± 23.0 years) but did not differ regarding sex distribution (CNI 69.4% males vs. control 69.1%). Traffic accidents were encountered more frequently in CNI cases (52.3% vs. 46.7%; p < 0.001; chi-squared test) and falls more commonly in the control group (45.2% vs. 37.1%; p < 0.001). CNI patients suffered more frequently from concomitant face injuries (28.2% vs. 17.5%; p < 0.001) and skull base fractures (51.0% vs. 23.5%; p < 0.001). Despite similar mean Injury Severity Score (CNI 21.8 ± 11.3; control 21.1 ± 11.7) and Glasgow Coma Scale score (CNI 10.9 ± 4.2, control 11.1 ± 4.4), there was a considerably higher proportion of anisocoria in CNI patients (20.1% vs. 11.2%; p < 0.001). Following primary treatment, 50.8% of CNI and 35.5% of control cases showed moderate to severe disability (Glasgow Outcome Scale score 3-4; p < 0.001).

CONCLUSION

CNI rarely occur in the context of TBI. When present, they indicate a higher likelihood of functional impairment following primary care and complicating skull base fractures should be suspected.

Brain injuries can set up an epileptogenic neuronal network

Development of epilepsy or epileptogenesis promotes recurrent seizures. As of today, there are no effective prophylactic therapies to prevent the onset of epilepsy. Contributing to this deficiency of preventive therapy is the lack of clarity in fundamental neurobiological mechanisms underlying epileptogenesis and lack of reliable biomarkers to identify patients at risk for developing epilepsy. This limits the development of prophylactic therapies in epilepsy. Here, neural network dysfunctions reflected by oscillopathies and microepileptiform activities, including neuronal hyperexcitability and hypersynchrony, drawn from both clinical and experimental epilepsy models, have been reviewed. This review suggests that epileptogenesis reflects a progressive and dynamic dysfunction of specific neuronal networks which recruit further interconnected groups of neurons, with this resultant pathological network mediating seizure occurrence, recurrence, and progression. In the future, combining spatial and temporal resolution of neuronal non-invasive recordings from patients at risk of developing epilepsy, together with analytics and computational tools, may contribute to determining whether the brain is undergoing epileptogenesis in asymptomatic patients following brain injury.

Moderate Intensity Treadmill Exercise Increases Survival of Newborn Hippocampal Neurons and Improves Neurobehavioral Outcomes after Traumatic Brain Injury

Physician-prescribed rest after traumatic brain injury (TBI) is both commonplace and an increasingly scrutinized approach to TBI treatment. Although this practice remains a standard of patient care for TBI, research of patient outcomes reveals little to no benefit of prescribed rest after TBI, and in some cases prolonged rest has been shown to interfere with patient well-being. In direct contrast to the clinical advice regarding physical activity after TBI, animal models of brain injury consistently indicate that exercise is neuroprotective and promotes recovery. Here, we assessed the effect of low and moderate intensity treadmill exercise on functional outcome and hippocampal neural proliferation after brain injury. Using the controlled cortical impact (CCI) mouse model of TBI, we show that 10 days of moderate intensity treadmill exercise initiated after CCI reduces anxiety-like behavior, improves hippocampus-dependent spatial memory, and promotes hippocampal proliferation and newborn neuronal survival. Pathophysiological measures including lesion volume and axon degeneration were not altered by exercise. Taken together, these data reveal that carefully titrated physical activity may be a safe and effective approach to promoting recovery after brain injury.

N-Acetyl-L-leucine improves functional recovery and attenuates cortical cell death and neuroinflammation after traumatic brain injury in mice

Traumatic brain injury (TBI) is a major cause of mortality and long-term disability around the world. Even mild to moderate TBI can lead to lifelong neurological impairment due to acute and progressive neurodegeneration and neuroinflammation induced by the injury. Thus, the discovery of novel treatments which can be used as early therapeutic interventions following TBI is essential to restrict neuronal cell death and neuroinflammation. We demonstrate that orally administered N-acetyl-l-leucine (NALL) significantly improved motor and cognitive outcomes in the injured mice, led to the attenuation of cell death, and reduced the expression of neuroinflammatory markers after controlled cortical impact (CCI) induced experimental TBI in mice. Our data indicate that partial restoration of autophagy flux mediated by NALL may account for the positive effect of treatment in the injured mouse brain. Taken together, our study indicates that treatment with NALL would be expected to improve neurological function after injury by restricting cortical cell death and neuroinflammation. Therefore, NALL is a promising novel, neuroprotective drug candidate for the treatment of TBI.

The Potential of Hydrogen for Improving Mental Disorders

In 2007, Ohsawa and colleagues reported that molecular hydrogen (H₂) gas significantly reduced the infarct volume size in a rat model of cerebral infarction, which was, at least, partially due to scavenging hydroxyl radicals. Since then, multiple studies have shown that H₂ has not only anti-oxidative but also anti-inflammatory and anti-apoptotic properties, which has ignited interest in the clinical use of H₂ in diverse diseases. A growing body of studies has indicated that H₂ affects both mental and physical conditions. Mental disorders are characterized by disordered mood, thoughts, and behaviors that affect the ability to function in daily life. However, there is no sure way to prevent mental disorders. Although antidepressant and antianxiety drugs relieve symptoms of depression and anxiety, they have efficacy limitations and are accompanied by a wide range of side effects. While mental disorders are generally thought to be caused by a variety of genetic and/or environmental factors, recent progress has shown that these disorders are strongly associated with increased oxidative and inflammatory stress. Thus, H₂ has received much attention as a novel therapy for the prevention and treatment of mental disorders. This review summarizes the recent progress in the use of H₂ for the treatment of mental disorders and other related diseases. We also discuss the potential mechanisms of the biomedical effects of H₂ and conclude that H₂ could offer relief to people suffering from mental disorders.

Region-Dependent Modulation of Neural Plasticity in Limbic Structures Early after Traumatic Brain Injury

Traumatic brain injury (TBI)-induced disruptions in synaptic function within brain regions and across networks in the limbic system may underlie a vulnerability for maladaptive plasticity and contribute to behavioral comorbidities. In this study we measured how synaptic proteins respond to lateral fluid percussion injury (FPI) brain regions known to regulate emotion and memory, including the basolateral amygdala (BLA), dorsal and ventral hippocampus (DH, VH), and medial prefrontal cortex (PFC). We investigated proteins involved in regulating plasticity, including synaptic glutamatergic a-amino-3-hydroxy5-methyl-4-isoxazolepropionic acid (AMPA; GluA1, GluA2) and N-methyl-D-aspartate (NMDA; NR1, NR2A, NR2B) receptor subunits as well as inhibitory gamma-aminobutyric acid (GABA) synthetic enzymes (GAD67, GAD65) via western blot. Adult male rats received a mild-moderate lateral FPI or sham surgery and ipsi- and contralateral BLA, DH, VH, and PFC were collected 6 h, 24 h, 48 h, and 7 days post-injury. In the ipsilateral BLA, there was a significant decrease in NR1 and GluA2 24 h after injury, whereas NR2A and NR2B were increased in the contralateral BLA at 48 h compared with sham. GAD67 was increased ipsilaterally at 24 h, but decreased contralaterally at 48 h in the BLA. In the DH, both NMDA (NR2A, NR2B) and GABA-synthetic (GAD65, GAD67) proteins were increased acutely at 6 h compared with sham. GAD67 was also robustly increased in the ipsilateral VH at 6 h. In the contralateral VH, NR2A significantly increased between 6 h and 24 h after FPI, whereas GAD65 was decreased across the same time-points in the contralateral VH. In the medial PFC at 24 h we saw bilateral increases in GAD67 and a contralateral decrease in GluA1. Later, there was a significant decrease in GAD67 in contralateral PFC from 48 h to 7 days post-injury. Collectively, these data suggest that lateral FPI causes a dynamic homeostatic response across limbic networks, leading to an imbalance of the proteins involved in plasticity in neural systems underlying cognitive and emotional regulation.

E2-BSA and G1 exert neuroprotective effects and improve behavioral abnormalities following traumatic brain injury: The role of classic and non-classic estrogen receptors

The role of classical and non-classical estrogen receptors (ERs) in mediating the neuroprotective effects of this hormone on brain edema and long-term behavioral disorders was evaluated after traumatic brain injury (TBI). Ovariectomized rats were divided as follows: E2 (17 β-estradiol), E2-BSA (E2 conjugated to bovine serum albumin), G1 [G-protein-coupled estrogen receptor agonist (GPER)] or their vehicle was injected following TBI, whereas ICI (classical estrogen receptor antagonist), G15 (GPER antagonist), ICI + G15, and their vehicle were injected before the induction of TBI and the injection of E2 and E2-BSA. Brain water (BWC) and Evans blue (EB) contents were measured 24 h and 5 h after TBI, respectively. Intracranial pressure (ICP) and cerebral perfusion pressure (CPP) were measured before and at different times after TBI. Locomotor activity, anxiety-like behavior, and spatial memory were assessed on days 3, 7, 14, and 21 after injury. E2, E2-BSA, and G1 prevented the increase of BWC and EB content after TBI, and these effects were inhibited by ICI and G15. ICI and G15 also inhibited the beneficial effects of E2, E2-BSA on ICP, as well as CPP, after trauma. E2, E2-BSA, and G1 prevented the cognitive deficiency and behavioral abnormalities induced by TBI. Similar to the above parameters, ICI and G15 also reversed this E2 and E2-BSA effects on days 3, 7, 14, and 21. Our findings indicated that the beneficial effects of E2-BSA and E2 were inhibited by both ICI and G15, suggesting that GPER and classic ERs were involved in mediating the long-term effects of E2.

Glial Activation in the Thalamus Contributes to Vestibulomotor Deficits Following Blast-Induced Neurotrauma

Vestibular impairment has become a frequent consequence following blast-related traumatic brain injury (bTBI) in military personnel and Veterans. Behavioral outcomes such as depression, fear and anxiety are also common comorbidities of bTBI. To accelerate pre-clinical research and therapy developments, there is a need to study the link between behavioral patterns and neuropathology. The transmission of neurosensory information often involves a pathway from the cerebral cortex to the thalamus, and the thalamus serves crucial integrative functions within vestibular processing. Pathways from the thalamus also connect with the amygdala, suggesting thalamic and amygdalar contributions to anxiolytic behavior. Here we used behavioral assays and immunohistochemistry to determine the sub-acute and early chronic effects of repeated blast exposure on the thalamic and amygdala nuclei. Behavioral results indicated vestibulomotor deficits at 1 and 3 weeks following repeated blast events. Anxiety-like behavior assessments depicted trending increases in the blast group. Astrogliosis and microglia activation were observed upon post-mortem pathological examination in the thalamic region, along with a limited glia response in the amygdala at 4 weeks. These findings are consistent with a diffuse glia response associated with bTBI and support the premise that dysfunction within the thalamic nuclei following repeated blast exposures contribute to vestibulomotor impairment.

Cognitive Dysfunction in Persons with Chronic Spinal Cord Injuries

Cognitive dysfunction (CD) is pervasive in individuals who have chronic spinal cord injuries (SCI). Although classically associated with concomitant traumatic brain injuries, many other causes have been proposed, including premorbid neuropsychological conditions, mood disorders, substance abuse, polypharmacy, chronic pain and fatigue, sleep apnea, autonomic dysregulation, post-intensive care unit syndrome, cortical reorganizations, and neuroinflammation. The consequences of CD are likely widespread, affecting rehabilitation and function. CD in those with SCI should be recognized, and potentially treated, in order to provide the best patient care.

Contributions of Interleukin-1 Receptor Signaling in Traumatic Brain Injury

Traumatic brain injury (TBI) in various forms affects millions in the United States annually. There are currently no FDA-approved therapies for acute injury or the chronic comorbidities associated with TBI. Acute phases of TBI are characterized by profound neuroinflammation, a process that stimulates the generation and release of proinflammatory cytokines including interleukin-1α (IL-1α) and IL-1β. Both forms of IL-1 initiate signaling by binding with IL-1 receptor type 1 (IL-1R1), a receptor with a natural, endogenous antagonist dubbed IL-1 receptor antagonist (IL-1Ra). The recombinant form of IL-1Ra has gained FDA approval for inflammatory conditions such as rheumatoid arthritis, prompting interest in repurposing these pharmacotherapies for other inflammatory diseases/injury states including TBI. This review summarizes the currently available preclinical and clinical literature regarding the therapeutic potential of inhibiting IL-1-mediated signaling in the context of TBI. Additionally, we propose specific research areas that would provide a greater understanding of the role of IL-1 signaling in TBI and how these data may be beneficial for the development of IL-1-targeted therapies, ushering in the first FDA-approved pharmacotherapy for acute TBI.

Gait Quality Assessment in Survivors from Severe Traumatic Brain Injury: An Instrumented Approach Based on Inertial Sensors

Despite existing evidence that gait disorders are a common consequence of severe traumatic brain injury (sTBI), the literature describing gait instability in sTBI survivors is scant. Thus, the present study aims at quantifying gait patterns in sTBI through wearable inertial sensors and investigating the association of sensor-based gait quality indices with the scores of commonly administered clinical scales. Twenty healthy adults (control group, CG) and 20 people who suffered from a sTBI were recruited. The Berg balance scale, community balance and mobility scale, and dynamic gait index (DGI) were administered to sTBI participants, who were further divided into two subgroups, severe and very severe, according to their score in the DGI. Participants performed the 10 m walk, the Figure-of-8 walk, and the Fukuda stepping tests, while wearing five inertial sensors. Significant differences were found among the three groups, discriminating not only between CG and sTBI, but also for walking ability levels. Several indices displayed a significant correlation with clinical scales scores, especially in the 10 m walking and Figure-of-8 walk tests. Results show that the use of wearable sensors allows the obtainment of quantitative information about a patient’s gait disorders and discrimination between different levels of walking abilities, supporting the rehabilitative staff in designing tailored therapeutic interventions.

Investigating Relations between Traumatic Brain Injury and Relationship Functioning among OIF/OEF Veterans

Traumatic brain injury (TBI) is one of the most common injuries among Veterans of Operation Iraqi Freedom (OIF) and Operation Enduring Freedom (OEF). TBI can negatively affect Veterans' close relationships, undermining an important source of support to aid recovery and rehabilitation. Given the complex symptom profile of TBI, the present research aimed to pinpoint key mediators of the link between TBI and marital functioning to help identify targets for intervention. Data from married OIF/OEF Veterans (N=188) were drawn from a larger sample. Mediation analyses simultaneously examined the potential roles of depressive, posttraumatic stress disorder (PTSD), and post-concussive symptoms in the association between TBI and Veterans' marital satisfaction. Results revealed associations between TBI and all three types of symptoms; however, only depressive symptoms independently mediated the association between TBI and marital satisfaction. These findings suggest depression as a mechanism by which TBI may interfere with healthy relationship functioning and highlight targets for intervention.

Sensory sensitivity as a link between concussive traumatic brain injury and PTSD

Traumatic brain injury (TBI) is one of the most common injuries to military personnel, a population often exposed to stressful stimuli and emotional trauma. Changes in sensory processing after TBI might contribute to TBI-post traumatic stress disorder (PTSD) comorbidity. Combining an animal model of TBI with an animal model of emotional trauma, we reveal an interaction between auditory sensitivity after TBI and fear conditioning where 75 dB white noise alone evokes a phonophobia-like phenotype and when paired with footshocks, fear is robustly enhanced. TBI reduced neuronal activity in the hippocampus but increased activity in the ipsilateral lateral amygdala (LA) when exposed to white noise. The white noise effect in LA was driven by increased activity in neurons projecting from ipsilateral auditory thalamus (medial geniculate nucleus). These data suggest that altered sensory processing within subcortical sensory-emotional circuitry after TBI results in neutral stimuli adopting aversive properties with a corresponding impact on facilitating trauma memories and may contribute to TBI-PTSD comorbidity.

Diazepam Inhibits Post-Traumatic Neurogenesis and Blocks Aberrant Dendritic Development

Traumatic brain injury (TBI) triggers a robust increase in neurogenesis within the dentate gyrus of the hippocampus, but these new neurons undergo aberrant maturation and dendritic outgrowth. Because gamma-aminobutyric acid (GABA)_A receptors (GABA_ARs) modulate dendritic outgrowth during constitutive neurogenesis and GABA_AR-modulating sedatives are often administered to human patients after TBI, we investigated whether the benzodiazepine, diazepam (DZP), alters post-injury hippocampal neurogenesis. We used a controlled cortical impact (CCI) model of TBI in adult mice, and administered DZP or vehicle continuously for 1 week after injury via osmotic pump. Although DZP did not affect the neurogenesis rate in control mice, it almost completely prevented the TBI-induced increase in hippocampal neurogenesis as well as the aberrant dendritic growth of neurons born after TBI. DZP did not reduce cortical injury, reactive gliosis, or cell proliferation early after injury, but decreased c-Fos activation in the dentate gyrus at both early and late time-points after TBI, suggesting an association between neuronal activity and post-injury neurogenesis. Because DZP blocks post-injury neurogenesis, further studies are warranted to assess whether benzodiazepines alter cognitive recovery or the development of complications after TBI.

A Tilted Axis: Maladaptive Inflammation and HPA Axis Dysfunction Contribute to Consequences of TBI

Each year approximately 1.7 million people sustain a traumatic brain injury (TBI) in the US alone. Associated with these head injuries is a high prevalence of neuropsychiatric symptoms including irritability, depression, and anxiety. Neuroinflammation, due in part to microglia, can worsen or even cause neuropsychiatric disorders after TBI. For example, mounting evidence demonstrates that microglia become “primed” or hyper-reactive with an exaggerated pro-inflammatory phenotype following multiple immune challenges. Microglial priming occurs after experimental TBI and correlates with the emergence of depressive-like behavior as well as cognitive dysfunction. Critically, immune challenges are various and include illness, aging, and stress. The collective influence of any combination of these immune challenges shapes the neuroimmune environment and the response to TBI. For example, stress reliably induces inflammation and could therefore be a gateway to altered neuropathology and behavioral decline following TBI. Given the increasing incidence of stress-related psychiatric disorders after TBI, the degree in which stress affects outcome is of particular interest. This review aims to highlight the role of the hypothalamic-pituitary-adrenal (HPA) axis as a key mediator of stress-immune pathway communication following TBI. We will first describe maladaptive neuroinflammation after TBI and how stress contributes to inflammation through both anti- and pro-inflammatory mechanisms. Clinical and experimental data describing HPA-axis dysfunction and consequences of altered stress responses after TBI will be discussed. Lastly, we will review common stress models used after TBI that could better elucidate the relationship between HPA axis dysfunction and maladaptive inflammation following TBI. Together, the studies described in this review suggest that HPA axis dysfunction after brain injury is prevalent and contributes to the dynamic nature of the neuroinflammatory response to brain injury. Experimental stressors that directly engage the HPA axis represent important areas for future research to better define the role of stress-immune pathways in mediating outcome following TBI.

Evaluation of extent and pattern of neurocognitive functions in mild and moderate traumatic brain injury patients by using Montreal Cognitive Assessment (MoCA) score as a screening tool: An observational study from India

INTRODUCTION

Cognitive impairment is one of the most important culprit influencing the long-term neurological outcome commonlyobserved in TBI survivors.

AIMS

To examine the performance of patients with Mild and Moderate traumatic brain injury (TBI) on the Montreal Cognitive Assessment (MoCA) using as a screening tool.

RESULTS

Total 228 (127 Mild TBI & 101 Moderate TBI) patients were recruited in this study. Results showed that patients with moderate TBI had lower score on the MoCA as compared to patients with mild TBI (p Value = 0.031). This difference was observed statistically significant among mild and moderate TBI for the cube copy (p = 0.039) and clock (p = 0.017) i.e. visuospatial/executive function, Digit span test (p value = 0.040) i.e. concentration and recall memory (p = 0.04). MoCA Score were higher for patients with higher GCS score at admission. Education status was also correlated with MoCA scores; those patients with higher level of education had significant association with higher MoCA scores (p value = 0.012). This study showed that age and gender were insignificant variables to determine cognitive function.

CONCLUSION

Assessment of cognitive impairment should be considered as a mandatory protocol while evaluating post TBI patients, even in cases of mild TBI. Visuospatial/Executive function, memory and attention are the most commonly impaired cognitive functions in patients of TBI, and these are the main domain of cognition which differentiates mild impairment from moderate impairment. This information enables us and provides insight to our experience to predict the burdens of problem and plan to develop post TBI dedicated rehabilitating programme.

Predictive value of early MRI findings on neurocognitive and psychiatric outcomes in patients with severe traumatic brain injury

BACKGROUND

Traumatic brain injury (TBI) is the major public health problem worldwide, particularly in the Middle East. Diffuse axonal injury (DAI) is commonly found in TBI. Although DAI can lead to physical and psychosocial disabilities, its prognostic value is still a matter of debate. Magnetic Resonance (MR) is more sensitive for detecting DAI lesions.

OBJECTIVE

To identify the radiological and clinical factors associated with the functional capacity one year after the traumatic brain injury.

METHODS

The study included 251 patients with severe head trauma for whom Brain MRI was done within one month after injury. Demographic, clinical, and radiological data were collected during hospitalization. Neurocognitive and psychiatric evaluation were done one year thereafter.

RESULTS

DAI was more frequent in our patients. Psychiatric disorders, cognitive impairment, and poor functional outcome were more common in patients with DAI especially those with cerebral hemisphere and brain stem lesion, and mixed lesions. Duration of post traumatic amnesia (DPTA), lost consciousness and hospital stay (DHS) as well as the volume of diffuse axonal injury (DAI) were associated with poor neurocognitive outcome. DPTA, and DAIV may be considered independent factors that could predict the neurocognitive outcome.

CONCLUSION

MRI following traumatic brain injury yields important prognostic information, with several lesion patterns significantly associated with poor long-term neurocognitive and psychiatric outcomes.

Sex-Dependent Effects of Mild Blast-induced Traumatic Brain Injury on Corticotropin-releasing Factor Receptor Gene Expression: Potential Link to Anxiety-like Behaviors

Traumatic brain injury (TBI) affects 1.7 million people in the United States every year, resulting in increased risk of death and disabilities. A significant portion of TBIs experienced by military personnel are induced by explosive blast devices. Active duty military personnel are especially vulnerable to mild blast-induced (mb)TBI and the associated long-term effects, such as anxiety disorders. Additionally, females are at an increased risk of being diagnosed with anxiety-related disorders. The mechanism by which mbTBI results in anxiety disorders in males and females is unknown. The sexually dimorphic corticotropin-releasing factor (CRF) is a brain signaling system linked to anxiety. CRF and its family of related peptides modulate anxiety-related behaviors by binding to CRF receptor subtypes 1 and 2 (CRFR1, CRFR2, respectively). These receptors are distributed throughout limbic structures that control behaviors related to emotion, memory, and arousal. Therefore, the aim of this study was to understand the link between mbTBI and anxiety by examining the impact of mbTBI on the CRFR system in male and female mice. mbTBI increased anxiety-like behaviors in both males and females (p < 0.05). In the present study, mbTBI did not alter CRFR1 gene expression in males or females. However, mbTBI disrupted CRFR2 gene expression in different limbic structures in males and females. In males, mbTBI increased baseline CRFR2 gene expression in the ventral hippocampus (p < 0.05) and decreased restraint-induced expression in the anterior bed nucleus of the stria terminalis (aBNST) and amygdala (p < 0.05). In females, mbTBI decreased restraint-induced CRFR2 gene expression in the dorsal hippocampus (p < 0.05). The inherent sex differences and the mbTBI-induced decrease in restraint-induced CRFR2 gene expression may contribute to anxiety-like behaviors. The results of the present study show that the response to mbTBI within the limbic structures modulates anxiety in a sex-dependent manner. The studies further suggest that CRFR2 may serve as a potential target to mitigate mbTBI effects.

Psychological Resilience Is Associated With Participation Outcomes Following Mild to Severe Traumatic Brain Injury

Traumatic brain injury (TBI) causes physical and cognitive-behavioral impairments that reduce participation in employment, leisure, and social relationships. Demographic and injury-related factors account for a small proportion of variance in participation post-injury. Personal factors such as resilience may also impact outcomes. This study aimed to examine the association of resilience alongside demographic, injury-related, cognitive, emotional, and family factors with participation following TBI. It was hypothesized that resilience would make an independent contribution to participation outcomes after TBI. Participants included 245 individuals with mild-severe TBI [Mage = 44.41, SDage = 16.09; post traumatic amnesia (PTA) duration M 24.95 days, SD 45.99] who completed the Participation Assessment with Recombined Tools-Objective (PART-O), TBI Quality of Life Resilience scale, Family Assessment Device General Functioning Scale, Rey Auditory Verbal Learning Test, National Adult Reading Test, and Hospital Anxiety and Depression Scale an average 4.63 years post-injury (SD 3.02, R 0.5-13). Multiple regression analyses were used to examine predictors of PART-O scores as the participation measure. Variables in the model accounted for a significant 38% of the variability in participation outcomes, F(13, 211) = 9.93, p < 0.05, R2 = 0.38, adjusted R2 = 0.34. Resilience was a significant predictor of higher participation, along with shorter PTA duration, more years since injury, higher education and IQ, and younger age. Mediation analyses revealed depression mediated the relationship between resilience and participation. As greater resilience may protect against depression and enhance participation this may be a focus of intervention.

Depression in the First Year after Traumatic Brain Injury

The aims of this study were to document the frequency of major and minor depressive episodes in the first year after traumatic brain injury (TBI), taking into account TBI severity and pre-morbid history of major depression, and to describe trajectories of depressive episodes. Participants were 227 adults who were hospitalized post-TBI (76% male; mean age = 41 years; 50% mild, 33% moderate, and 17% severe TBI). Major and minor depressive episodes were assessed with the Mini International Neuropsychiatric Interview at three time points (4, 8, and 12 months after TBI). Overall, 29% of participants had a major depressive episode in at least one of the three assessments, with fairly stable rates across assessments. Participants with mild TBI were more likely than those with moderate/severe TBI to be diagnosed with major depression, as were individuals with a positive pre-morbid history of depression compared to those without such history. In addition, 13% of participants had a minor depressive episode in at least one of the three assessments. Rates of minor depression significantly decreased from 4 to 8-12 months post-injury. Results also revealed a wide variety of trajectories of depressive episodes across assessments. Of note, 52% of major depression cases still fulfilled diagnostic criteria 4 months later, whereas 38% of minor depression cases deteriorated to major depression at the following assessment. These findings suggest that depression is highly prevalent after TBI, and monitoring of patients with subthreshold depressive symptoms is warranted in order to prevent the development of full-blown major depressive episodes.

Injury mechanism of midfacial fractures in football causes in over 40% typical neurological symptoms of minor brain injuries

PURPOSE

The injury mechanisms of midfacial fractures may be typical causes of concussion, but hardly any scientific data on midfacial injuries sustained in football are available. Head and brain trauma represent frequent injuries in athletes of different sports that require appropriate treatment by sports and trauma physicians. This study investigated the management of midfacial fractures in football and the association of such fractures with concomitant brain injury.

METHODS

In a prospective cohort study lasting 24 months (2012 to 2013), midfacial injuries of football players were analysed with regard to the injury mechanisms, first aid procedures on the field, treatment and return-to-play. To analyse concomitant and potentially overlooked minor brain injuries due to the trauma, we retrospectively investigated the neurological symptoms of the study population.

RESULTS

The study included 132 football players (37 semi-professionals and 95 amateurs) with midfacial fractures. The main injury mechanisms were head-to-head and head-to-elbow trauma. The mean period of return-to-play after trauma was 33.5 days, which was significantly shortened if a protective face mask was worn (mean 10.4 days earlier, p = 0.0006). Semi-professional football players returned to play earlier (p = 0.009) and more often used protective face masks (p = 0.001). 55 players (41.6%) had neurological symptoms immediately after trauma as a possible sign of concomitant minor brain injury. 5 of 132 players with concussion had been hospitalised for 24 h, but no persistent neurological symptoms were detected.

CONCLUSION

In football, midfacial fractures represent moderate-to-severe injuries with time away from sports of more than 4 weeks. Over 40% of athletes with a midfacial fracture showed concomitant neurological symptoms as a sign of minor brain injury. Therefore, sports physicians and other staff supervising athletes in daily practice should be aware of the presence of neurological symptoms.

LEVEL OF EVIDENCE

Level III.

Biological activities of (-)-epicatechin and (-)-epicatechin-containing foods: Focus on cardiovascular and neuropsychological health

Recent studies have suggested that certain (-)-epicatechin-containing foods have a blood pressure-lowering capacity. The mechanisms underlying (-)-epicatechin action may help prevent oxidative damage and endothelial dysfunction, which have both been associated with hypertension and certain brain disorders. Moreover, (-)-epicatechin has been shown to modify metabolic profile, blood's rheological properties, and to cross the blood-brain barrier. Thus, (-)-epicatechin causes multiple actions that may provide unique synergy beneficial for cardiovascular and neuropsychological health. This review summarises the current knowledge on the biological actions of (-)-epicatechin, related to cardiovascular and brain functions, which may play a remarkable role in human health and longevity.

Neuroinflammation in traumatic brain injury: A chronic response to an acute injury

Every year, approximately 1.4 million US citizens visit emergency rooms for traumatic brain injuries. Formerly known as an acute injury, chronic neurodegenerative symptoms such as compromised motor skills, decreased cognitive abilities, and emotional and behavioral changes have caused the scientific community to consider chronic aspects of the disorder. The injury causing impact prompts multiple cell death processes, starting with neuronal necrosis, and progressing to various secondary cell death mechanisms. Secondary cell death mechanisms, including excitotoxicity, oxidative stress, mitochondrial dysfunction, blood-brain barrier disruption, and inflammation accompany chronic traumatic brain injury (TBI) and often contribute to long-term disabilities. One hallmark of both acute and chronic TBI is neuroinflammation. In acute stages, neuroinflammation is beneficial and stimulates an anti-inflammatory response to the damage. Conversely, in chronic TBI, excessive inflammation stimulates the aforementioned secondary cell death. Converting inflammatory cells from pro-inflammatory to anti-inflammatory may expand the therapeutic window for treating TBI, as inflammation plays a role in all stages of the injury. By expanding current research on the role of inflammation in TBI, treatment options and clinical outcomes for afflicted individuals may improve. This paper is a review article. Referred literature in this paper has been listed in the references section. The data sets supporting the conclusions of this article are available online by searching various databases, including PubMed. Some original points in this article come from the laboratory practice in our research center and the authors' experiences.

17β-estradiol rescues damages following traumatic brain injury from molecule to behavior in mice

Traumatic brain injury (TBI) is a public health concern, and causes cognitive dysfunction, emotional disorders, and neurodegeration, as well. The currently available treatments are all symptom-oriented with unsatifying efficacy. It is highly demanded to understand its underlying mechanisms. Controlled cortical impact (CCI) was used to induce TBI in aged female mice subjected to ovariectomy. Brain damages were assessed with neurological severity score, brain infarction and edema. Morris water maze and elevated plus maze were applied to evaluate the levels of anxiety. Apoptosis in the hippocampus was assayed with Fluoro-Jade B staining and TUNEL staining. Western blot was employed to measure the expression of NMDA receptor subunits and phosphorylation of ERK1/2, and biochemical assays were used to estimate oxidative stress. 17beta-Estradiol (E2) was intraperitoneally administered at 10-80 μg/kg once per day for 7 consecutive days before or after CCI. Chronic administration of E2 both before and immediately after CCI conferred neuroprotection, reducing neurological severity score, brain infarction, and edema in TBI mice. Additionally, E2 improved many aspects of deleterious effects of TBI on the hippocampus, including neuronal apoptosis, dysfunction in spatial memory, reduction in NR2B, enhancement of oxidative stress, and activation of ERK1/2 pathway. The present study provides clue for the notion that E2 has therapeutic potential for both prevention and intervention of TBI-induced brain damages.

The relationship between neuropsychological performance and depression in patients with traumatic brain injury

Traumatic brain injury is a multi-faceted condition that affects individuals on physical, cognitive, and emotional levels. The study investigated the relationship between depression and neuropsychological performance in a group with traumatic brain injury. A retrospective review was conducted on 75 participants who completed neuropsychological assessments. Information on clinical characteristics, sociodemographic information, neuropsychological outcomes, and Beck Depression Inventory scores were included in the analysis. Results indicated that 36% of the participants reported experiencing severe symptoms of depression, 28% moderate symptoms of depression, and 36% mild/minimal symptoms of depression. Performance on the Rey Auditory Verbal Learning Test indicated inverse relationships with depression scores suggesting that traumatic brain injury patients with lower depression scores perform better on verbal memory tasks. Similarly, findings for the written and oral versions of the Symbol Digit Modalities Test reflected inverse correlations with depression scores, indicating that lower depression scores are correlated with increased processing speed and capacity. A significant positive association between the time taken to complete the Trail Making Test Trail A and Trail B and depression scores was found, suggesting that higher depression scores in this sample were related to slower performance speed and lower executive performance. When specific clinical and sociodemographic variables were included as covariates in a partial correlational analysis, neuropsychological performance indicators and depression scores remained significant for Symbol Digit Modalities Test (oral and written), the Rey Auditory Verbal Learning Test Retrieval and Recognition trials, and Trail Making Test (Trail B). This study indicates that in a traumatic brain injury cohort, depression levels are significantly associated with specific neuropsychological performance measures. The findings of this study have implications for psychosocial treatment planning after a traumatic brain injury and contribute to our understandings of the inter-relationship between cognition and emotion.

Increased Risk of Stroke in Patients of Concussion: A Nationwide Cohort Study

Long-term morbidities can develop after traumatic brain injury (TBI). Some studies have suggested that the risk of stroke is higher after TBI, but the association between concussion and stroke remains unclear. Using a national cohort, the authors analyzed the incidence of both hemorrhagic and ischemic strokes in patients with previous concussion. A representative cohort of approximately one million people was followed up for four years. Patients with new-onset concussion were identified (n = 13,652) as the concussion group. Subsequently, the incidence rates of later stroke events in the concussion group were compared to a sex-, age- and propensity score–matched comparison group (n = 13,652). The overall incidence rate of stroke in the concussion group was higher than that of the comparison group (9.63 versus 6.52 per 1000 person-years, p < 0.001). Significantly higher stroke risk was observed in the concussion group than in the comparison group (crude hazard ratio 1.48, p < 0.001; adjusted HR 1.65, p < 0.001). In the concussion group, the cumulative incidence rates of both ischemic stroke and hemorrhagic stroke were higher than those of the comparison group (8.9% vs. 5.8% and 2.7% vs. 1.6%, respectively, both p < 0.001). Concussion is an independent risk factor for both ischemic and hemorrhagic strokes. Prevention and monitoring strategies of stroke are therefore suggested for patients who have experienced concussion.

Neuropsychiatric aspects of concussion: acute and chronic sequelae

Concussion – also known as mild traumatic brain injury – is a transient disturbance of neurological function resulting from traumatic forces imparted to the brain that often produce cognitive, behavioral and systemic symptoms. In this review of the literature, we discuss the pathophysiology of both acute and chronic neuropsychiatric sequelae of concussions, followed by a brief overview of evaluation and management of these sequelae.

Sex-Related Differences in Emotion Recognition in Multi-concussed Athletes

OBJECTIVES

Concussion is defined as a complex pathophysiological process affecting the brain. Although the cumulative and long-term effects of multiple concussions are now well documented on cognitive and motor function, little is known about their effects on emotion recognition. Recent studies have suggested that concussion can result in emotional sequelae, particularly in females and multi-concussed athletes. The objective of this study was to investigate sex-related differences in emotion recognition in asymptomatic male and female multi-concussed athletes.

METHODS

We tested 28 control athletes (15 males) and 22 multi-concussed athletes (10 males) more than a year since the last concussion. Participants completed the Post-Concussion Symptom Scale, the Beck Depression Inventory-II, the Beck Anxiety Inventory, a neuropsychological test battery and a morphed emotion recognition task. Pictures of a male face expressing basic emotions (anger, disgust, fear, happiness, sadness, surprise) morphed with another emotion were randomly presented. After each face presentation, participants were asked to indicate the emotion expressed by the face.

RESULTS

Results revealed significant sex by group interactions in accuracy and intensity threshold for negative emotions, together with significant main effects of emotion and group.

CONCLUSIONS

Male concussed athletes were significantly impaired in recognizing negative emotions and needed more emotional intensity to correctly identify these emotions, compared to same-sex controls. In contrast, female concussed athletes performed similarly to same-sex controls. These findings suggest that sex significantly modulates concussion effects on emotional facial expression recognition. (JINS, 2017, 23, 65-77).

Connexin40 correlates with oxidative stress in brains of traumatic brain injury rats

BACKGROUND

Oxidative stress is an important factor in the pathophysiologic changes after traumatic brain injury (TBI). Connexin43 (Cx43) was reported to contribute to cerebral damage. However, the impacts of Cx40 have not been investigated in detail.

OBJECTIVE

In the present study, we hypothesized that Cx40 was involved in oxidative stress-induced brain injury after TBI.

METHODS

The controlled cortical impact (CCI) model was introduced to Wistar rats as a TBI model. Neurological deficits, oxidative stress and Cx40 were evaluated in TBI rats and N-acetylcysteine (NAC)-treated TBI rats. Neurological severity score (NSS) was used to assess neurological deficits. Brain infarction was measured by histo-staining. Brain edema was evaluated by measuring the brain water content. Cortex samples were collected to measure the tissue levels of malonyldialdehyde (MDA), nitric oxide (NO) and glutathione (GSH) and NADPH oxidase activity. Cx40 expression was determined by Western-blot.

RESULTS

TBI-induced brain injuries gradually increased from 6 h to 24 h post CCI, and the severity remained till 72 h. The level of oxidative stress was consistent with the extent of neurological deficits. Cx40 was upregulated after TBI in a linear correlated manner with increased oxidative stress. With NAC intervention, both neurological deficits and oxidative stress were significantly attenuated. Meanwhile, elevated Cx40 expression in cortex was also prevented by NAC treatment.

CONCLUSION

These studies revealed the relationship between levels of Cx40 and oxidative stress after TBI. The cortex Cx40 expression was positively correlated with the cerebral oxidative stress, indicating the involvement of Cx40 in the progress of brain damage.

Prolonged Repetitive Head Trauma Induces a Singular Chronic Traumatic Encephalopathy-Like Pathology in White Matter Despite Transient Behavioral Abnormalities

Repetitive mild traumatic brain injury (rmTBI), resulting from insults caused by an external mechanical force that disrupts normal brain function, has been linked to the development of neurodegenerative diseases, such as chronic traumatic encephalopathy and Alzheimer disease; however, neither the severity nor frequency of head injury required to trigger adverse behavioral outcomes is well understood. In this study, the administration of 30 head impacts using two different weights to lightly anesthetized, completely unrestrained mice established a paradigm that simulates the highly repetitive nature of sports- and military-related head injury. As the number of head impacts increases, the time to recover consciousness diminishes; however, both the sensorimotor function and behavioral outcomes of impacted mice evolve during the ensuing weeks. Postmortem analyses reveal robust Alzheimer disease and chronic traumatic encephalopathy-like conditions that manifest in a singular manner throughout the white matter concomitant with evidence of chronic oligodendrogenesis. Our data suggest that latency to recover the righting reflex may be an inadequate measure of injury severity and imply that exposure to repeated head impacts may mask the severity of an underlying and developing neuropathologic condition that does not manifest itself until long after head collisions cease. In addition, our data indicate that there is a cumulative and dose-dependent effect of repetitive head impacts that induces the neurobehavioral and neuropathologic outcomes seen in humans with a history of rmTBI.