Physical exercise ameliorates deficits induced by traumatic brain injury

Impact of menopause-associated frailty on traumatic brain injury

Navigating menopause involves traversing a complex terrain of hormonal changes that extend far beyond reproductive consequences. Menopausal transition is characterized by a decrease in estradiol-17β (E2), and the impact of menopause resonates not only in the reproductive system but also through the central nervous system, musculoskeletal, and gastrointestinal domains. As women undergo menopausal transition, they become more susceptible to frailty, amplifying the risk and severity of injuries, including traumatic brain injury (TBI). Menopause triggers a cascade of changes leading to a decline in muscle mass, accompanied by diminished tone and excitability, thereby restricting the availability of irisin, a crucial hormone derived from muscles. Concurrently, bone mass undergoes reduction, culminating in the onset of osteoporosis and altering the dynamics of osteocalcin, a hormone originating from bones. The diminishing levels of E2 during menopause extend their influence on the gut microbiota, resulting in a reduction in the availability of tyrosine, tryptophan, and serotonin metabolites, affecting neurotransmitter synthesis and function. Understanding the interplay between menopause, frailty, E2 decline, and the intricate metabolisms of bone, gut, and muscle is imperative when unraveling the nuances of TBI after menopause. The current review underscores the significance of accounting for menopause-associated frailty in the incidence and consequences of TBI. The review also explores potential mechanisms to enhance gut, bone, and muscle health in menopausal women, aiming to mitigate frailty and improve TBI outcomes.

Moderate-Severe TBI as a Progressive Disorder: Patterns and Predictors of Cognitive Declines in the Chronic Stages of Injury

BACKGROUND

Moderate-severe traumatic brain injury (TBI) has been associated with progressive cognitive decline in the chronic injury stages in a small number of studies.

OBJECTIVE

This study aimed to (i) replicate our previous findings of decline from 1 to 3+ years post-injury in a larger, non-overlapping sample and (ii) extend these findings by examining the proportion of decliners in 2 earlier time windows, and by investigating novel predictors of decline.

METHODS

N = 48 patients with moderate-severe TBI underwent neuropsychological assessment at 2, 5, 12 months, and 30+ months post-injury. We employed the Reliable Change Index (RCI) to evaluate decline, stability and improvement across time and logistic regression to identify predictors of decline (demographic/cognitive reserve; injury-related).

RESULTS

The proportions of patients showing decline were: 12.5% (2-5 months post-injury), 17% (5-12 months post-injury), and 27% (12-30+ months post-injury). Measures of verbal retrieval were most sensitive to decline. Of the predictors, only left progressive hippocampal volume loss from 5 to 12 months post-injury significantly predicted cognitive decline from 12 to 30+ months post-injury.

CONCLUSIONS

Identical to our previous study, 27% of patients declined from 12 to 30+ months post-injury. Additionally, we found that the further from injury, the greater the proportion of patients declining. Importantly, earlier progressive hippocampal volume loss predicted later cognitive decline. Taken together, the findings highlight the need for ongoing research and treatment that target these deleterious mechanisms affecting patients in the chronic stages of moderate-severe TBI.

Lower and higher volumes of physical exercise build up brain reserves against memory deficits triggered by a head injury in mice

Decreasing neurotrophic support and impaired mitochondrial bioenergetics are key mechanisms for long-term neurodegeneration and cognitive decline after traumatic brain injury (TBI). We hypothesize that preconditioning with lower and higher volumes of physical exercise upregulates the CREB-BDNF axis and bioenergetic capability, which might serve as neural reserves against cognitive impairment after severe TBI. Using a running wheel mounted in the home cage, mice were engaged in lower (LV, 48 h free access, and 48 h locked) and higher (HV, daily free access) exercise volumes for thirty days. Subsequently, LV and HV mice remained for additional thirty days in the home cage with the running wheel locked and were euthanized. The sedentary group had the running wheel always locked. For the same type of exercise stimulus in a given time, daily workout presents higher volume than alternate days workout. The total distance ran in the wheel was the reference parameter to confirm distinct exercise volumes. On average, LV exercise ran 27.522 m and HV exercise ran 52.076 m. Primarily, we investigate whether LV and HV protocols increase neurotrophic and bioenergetic support in the hippocampus thirty days after exercise ceased. Regardless of volume, exercise increased hippocampal pCREBSer133-CREB-proBDNF-BDNF signaling and mitochondrial coupling efficiency, excess capacity, and leak control, that may compose the neurobiological basis for neural reserves. Further, we challenge these neural reserves against secondary memory deficits triggered by a severe TBI. After thirty days of exercise LV and HV, and sedentary (SED) mice were submitted to the CCI model. Mice remained for additional thirty days in the home cage with the running wheel locked. The mortality after severe TBI was approximately 20% in LV and HV, while in the SED was 40%. Also, LV and HV exercise sustained hippocampal pCREBSer133-CREB-proBDNF-BDNF signaling, mitochondrial coupling efficiency, excess capacity, and leak control for thirty days after severe TBI. Corroborating these benefits, the mitochondrial H2O2 production linked to complexes I and II was attenuated by exercise regardless of the volume. These adaptations attenuated spatial learning and memory deficits caused by TBI. In summary, preconditioning with LV and HV exercise builds up long-lasting CREB-BDNF and bioenergetic neural reserves that preserve memory fitness after severe TBI.

Characteristics, Outcomes, Sex and Gender Considerations of Community-Based Physical Activity Interventions after Moderate-to-Severe Traumatic Brain Injury: Scoping Review

OBJECTIVE

This scoping review mapped the current evidence about community-based physical activity (PA) interventions for individuals with moderate-to-severe traumatic brain injury (TBI) and identified the reported health-related outcomes, measurement tools used, and considerations given to sex and gender.

METHODS

Searches were conducted in six academic databases for peer-reviewed articles (MEDLINE, EMBASE, Cochrane CENTRAL, CINAHL, SPORTDiscus, and PEDro). PRISMA Scoping Review guidelines were followed. Two reviewers independently screened articles for inclusion and extracted data for the analysis with a modified Consensus on Exercise Reporting Template (CERT). Health-related outcomes were classified with domains of the International Classification of Function, Disability and Health (ICF).

RESULTS

19 studies were identified. Seven PA intervention types were included. CERT scores varied (M = 12.74, SD = 3.51 items), with limited details for replication. ICF outcomes focused on improving body functions (74%), activities and participation (14%), environmental factors (1%), and other: not covered (11%). Only four studies (21%) stratified their results by sex or gender.

CONCLUSIONS

Identified PA interventions from this review revealed common characteristics that led to improved outcomes. Proposed recommendations aim to improve future research and community practice. There is a pressing need for more sex and gender considerations in PA research after moderate-to-severe TBI.

Physical Exercise as a Modulator of Vascular Pathology and Thrombin Generation to Improve Outcomes After Traumatic Brain Injury

Disruption of the blood-brain barrier and occurrence of coagulopathy after traumatic brain injury (TBI) have important implications for multiple secondary injury processes. Given the extent of post-traumatic changes in neuronal function, significant alterations in some targets, such thrombin (a protease that plays a physiological role in maintaining blood coagulation), play an important role in TBI-induced pathophysiology. Despite the magnitude of thrombin in synaptic plasticity being concentration-dependent, the mechanisms underlying TBI have not been fully elucidated. The understanding of this post-injury neurovascular dysregulation is essential to establish scientific-based rehabilitative strategies. One of these strategies may be supporting physical exercise, considering its relevance in reducing damage after a TBI. However, there are caveats to consider when interpreting the effect of physical exercise on neurovascular dysregulation after TBI. To complete this picture, this review will describe how the interactions established between blood-borne factors (such as thrombin) and physical exercise alter the TBI pathophysiology.

Post-exercise cognitive testing to assess persisting alterations in athletes with a history of concussion

Primary Objective: To determine whether a physical exercise protocol could reveal persistent cognitive alterations in university athletes with a history of concussion (HOC). Thirty-four HOC and 34 controls participated in this study.Research Design: Cross-sectional.Methods and Procedures: The exercise protocol consisted of a 20-min bout on a stationary bike at 80% of the theoretical maximal heart rate. Before and after the exercise, participants performed a computerized switch task designed specifically to recruit executive functions. Group × Condition (pre- and post-exercise) repeated measures of ANCOVAs for accuracy, reaction time, and inverse efficiency score on the switch task were conducted. Chi-square tests were run to determine if the proportion of HOC and controls who underperformed (at least 2SD lower than the control group's average score) at rest and post-exercise were similar. Whilst no interaction or main effects were found with ANCOVAs, significantly more HOC athletes (21%) underperformed following exercise than at rest (3%) on the switch task, p = .02. The current results indicate that an acute bout of exercise can reveal persistent alterations that are not present at rest in the protracted phase of concussion. They also highlight the importance of considering inter-individual differences in recovery trajectories.

The impact of exercise, sleep, and diet on neurocognitive recovery from mild traumatic brain injury in older adults: A narrative review

Mild traumatic brain injury (mTBI) accounts for a large majority of traumatic brain injuries sustained globally each year. Older adults, who are already susceptible to age-related declines to neurocognitive health, appear to be at an increased risk of both sustaining an mTBI and experiencing slower or impaired recovery. There is also growing evidence that mTBI is a potential risk factor for accelerated cognitive decline and neurodegeneration. Lifestyle-based interventions are gaining prominence as a cost-effective means of maintaining cognition and brain health with age. Consequently, inter-individual variations in exercise, sleep, and dietary patterns could influence the trajectory of post-mTBI neurocognitive recovery, particularly in older adults. This review synthesises the current animal and human literature centred on the mechanisms through which lifestyle-related habits and behaviours could influence acute and longer-term neurocognitive functioning following mTBI. Numerous neuroprotective processes which are impacted by lifestyle factors have been established in animal models of TBI. However, the literature is characterised by a lack of translation to human samples and limited appraisal of the interaction between ageing and brain injury. Further research is needed to better establish the therapeutic utility of applying lifestyle-based modifications to improve post-mTBI neurocognitive outcomes in older adults.

Community-Based Physical Activity Interventions for Individuals with Moderate to Severe Traumatic Brain Injury: Scoping Review Protocol

Background

Long-term physical, cognitive, and psychosocial problems resulting from moderate to severe traumatic brain injury (TBI) can prevent individuals from returning to preinjury lifestyles because of significant challenges with employment, leisure, and relationships. While physical activity (PA) is proposed as a cost-effective method to alleviate problems after moderate to severe TBI, there is no review to date that synthesizes the evidence for PA in the community-based context. Further, although sex- and gender-based considerations in research are considered requisite to good science, there is no review on PA and TBI that has included this explicit focus.

Objective

The purpose of this review is to map and synthesize the current evidence identified through a systematic search of community-based PA interventions for individuals of all ages with moderate to severe TBI and provide an overview of that evidence by asking the following research questions: (1) what are the characteristics of community-based PA programs for individuals with moderate to severe TBI, (2) what are the reported health-related outcomes and measurement tools used to evaluate them, and (3) what considerations have been given to sex and/or gender?

Methods

Searches will be conducted of six academic databases for peer-reviewed articles. Two reviewers will independently screen the articles for inclusion and extract data for the analysis. The extracted data will be coded according to the Consensus on Exercise Reporting Template checklist and the Template for Intervention Description and Replication checklist to provide sufficient detail for replication.

Results

The abstract screening was completed by two reviewers and the extracted data were analyzed. A qualitative synthesis and description of community-based PA interventions for individuals with moderate to severe TBI will be provided.

Conclusions

This scoping review will generate new knowledge from published and publicly available literature. Dissemination of the results will include activities related to knowledge transfer for community-based PA after moderate to severe TBI for future research and practice. Evidence-based recommendations, future directions, potential limitations, use of online/digital components, and the possible need for a systematic review will be discussed as well.

International Registered Report Identifier (IRRID)

DERR1-10.2196/24689

Nutritional interventions to improve neurophysiological impairments following traumatic brain injury: A systematic review

Traumatic brain injury (TBI) accounts for significant global health burden. Effects of TBI can become chronic even following mild injury. There is a need to develop effective therapies to attenuate the damaging effects of TBI and improve recovery outcomes. This literature review using a priori criteria (PROSPERO; CRD42018100623) summarized 43 studies between January 1998 and July 2019 that investigated nutritional interventions (NUT) delivered with the objective of altering neurophysiological (NP) outcomes following TBI. Risk of bias was assessed for included studies, and NP outcomes recorded. The systematic search resulted in 43 of 3,748 identified studies met inclusion criteria. No studies evaluated the effect of a NUT on NP outcomes of TBI in humans. Biomarkers of morphological changes and apoptosis, oxidative stress, and plasticity, neurogenesis, and neurotransmission were the most evaluated NP outcomes across the 43 studies that used 2,897 animals. The risk of bias was unclear in all reviewed studies due to poorly detailed methodology sections. Taking these limitations into account, anti-oxidants, branched chain amino acids, and ω-3 polyunsaturated fatty acids have shown the most promising pre-clinical results for altering NP outcomes following TBI. Refinement of pre-clinical methodologies used to evaluate effects of interventions on secondary damage of TBI would improve the likelihood of translation to clinical populations.

Western diet aggravates neuronal insult in post-traumatic brain injury: Proposed pathways for interplay

Traumatic brain injury (TBI) is a global health burden and a major cause of disability and mortality. An early cascade of physical and structural damaging events starts immediately post-TBI. This primary injury event initiates a series of neuropathological molecular and biochemical secondary injury sequelae, that last much longer and involve disruption of cerebral metabolism, mitochondrial dysfunction, oxidative stress, neuroinflammation, and can lead to neuronal damage and death. Coupled to these events, recent studies have shown that lifestyle factors, including diet, constitute additional risk affecting TBI consequences and neuropathophysiological outcomes. There exists molecular cross-talk among the pathways involved in neuronal survival, neuroinflammation, and behavioral outcomes, that are shared among western diet (WD) intake and TBI pathophysiology. As such, poor dietary intake would be expected to exacerbate the secondary damage in TBI. Hence, the aim of this review is to discuss the pathophysiological consequences of WD that can lead to the exacerbation of TBI outcomes. We dissect the role of mitochondrial dysfunction, oxidative stress, neuroinflammation, and neuronal injury in this context. We show that currently available data conclude that intake of a diet saturated in fats, pre- or post-TBI, aggravates TBI, precludes recovery from brain trauma, and reduces the response to treatment.

Cultivating a healthy neuro‐immune network: A health psychology approach

The field of psychoneuroimmunology (PNI) examines interactions among psychological and behavioral states, the brain, and the immune system. Research in PNI has elegantly documented effects of stress at multiple levels of the neuro-immune network, with profound implications for both physical and mental health. In this review, we consider how the neuro-immune network might be influenced by "positive" psychological and behavioral states, focusing on positive affect, eudaimonic well-being, physical activity, and sleep. There is compelling evidence that these positive states and behaviors are associated with changes in immune activity in the body, including reductions in peripheral inflammatory processes relevant for physical health. Growing evidence from animal models also suggests effects of positive states on immune cells in the brain and the blood-brain barrier, which then impact critical aspects of mood, cognition, and behavior. Tremendous advances are being made in our understanding of neuro-immune dynamics; one of the central goals of this review is to highlight recent preclinical research in this area and consider how we can leverage these findings to investigate and cultivate a healthy neuro-immune network in humans.

Treadmill exercise improves memory by up-regulating dopamine and down-regulating D2 dopamine receptor in traumatic brain injury rats

Traumatic brain injury (TBI) causes a variety of neuropathological manifestations including cognitive, emotional, physiological and psychological deficits. Physical exercise is known to ameliorate neurological impairments induced by various brain injuries. We investigated the effects of treadmill exercise on memory impairments due to TBI in relation to dopamine and D₂ dopamine receptor. TBI was induced with an electromagnetic-controlled cortical impact device. The rats in the exercise groups were scheduled to run on a treadmill for 30 min once a day for 28 days after TBI induction. Then, step-down avoidance task, radial 8-arm maze test, immunohistochemistry for tyrosine hydroxylase (TH), and western blot for D₂ dopamine receptor were performed. TBI impaired short-term and spatial learning memories. TBI decreased TH expressions in the prefrontal cortex (PFC), striatum, hippocampus dentate gyrus, and substantia nigra (SN). By contrast, the expressions of D₂ dopamine receptor in the PFC, striatum, hippocampus, and SN were increased by TBI. Treadmill exercise alleviated the impairments of short-term and spatial learning memories observed in TBI rats. TH expression was decreased and D₂ dopamine receptor expression was increased in TBI rats. Treadmill exercise enhanced TH expression and suppressed D₂ dopamine receptor expression in TBI rats. TBI deteriorated short-term and spatial learning memories, in contrast, treadmill exercise alleviated the TBI-induced memory impairments by up-regulating dopamine level and down-regulating D₂ dopamine receptor expression.

Housing for People with an Acquired Brain or Spinal Injury: Mapping the Australian Funding Landscape

This research aimed to synthesize housing supports funded by 20 major insurance-based schemes for Australians with an acquired brain injury (ABI) or spinal cord injury (SCI). Publicly available grey literature (i.e., primary information from respective scheme websites) was systematically reviewed and compared. There were notable differences between the different scheme types (disability vs. workers compensation schemes) and across different States. Collectively, scheme funding was more likely to be focused on housing infrastructure and service delivery, than on tenancy support. Australians who are least likely to benefit from the current funding context are those whose home cannot be reasonably modified, are wanting to build or purchase a new home, do not have suitable, alternative short- or long-term housing options if their current home is not feasible, require support to maintain occupancy of their home or financial assistance to move into a new home, may benefit from case management services, family supports, and assistance animals, and/or cannot afford their rent or home loan repayments. Several interactions, inconsistencies, contradictions, and gaps that warrant further attention were also revealed. This review has highlighted the need for policy makers to provide transparent information about housing entitlements for individuals with ABI or SCI, and their families. A unified, evidence-based framework to guide the funding of housing and housing support services may increase the consistency of interventions available to people with ABI or SCI and, therefore, improve outcomes.

Making sense of gut feelings in the traumatic brain injury pathogenesis

Traumatic brain injury (TBI) is a devastating condition which often initiates a sequel of neurological disorders that can last throughout lifespan. From metabolic perspective, TBI also compromises systemic physiology including the function of body organs with subsequent malfunctions in metabolism. The emerging panorama is that the effects of TBI on the periphery strike back on the brain and exacerbate the overall TBI pathogenesis. An increasing number of clinical reports are alarming to show that metabolic dysfunction is associated with incidence of long-term neurological and psychiatric disorders. The autonomic nervous system, associated hypothalamic-pituitary axis, and the immune system are at the center of the interface between brain and body and are central to the regulation of overall homeostasis and disease. We review the strong association between mechanisms that regulate cell metabolism and inflammation which has important clinical implications for the communication between body and brain. We also discuss the integrative actions of lifestyle interventions such as diet and exercise on promoting brain and body health and cognition after TBI.

TBI Rehabilomics Research: Conceptualizing a humoral triad for designing effective rehabilitation interventions

Most areas of medicine use biomarkers in some capacity to aid in understanding how personal biology informs clinical care. This article draws upon the Rehabilomics research model as a translational framework for programs of precision rehabilitation and intervention research focused on linking personal biology to treatment response using biopsychosocial constructs that broadly represent function and that can be applied to many clinical populations with disability. The summary applies the Rehabilomics research framework to the population with traumatic brain injury (TBI) and emphasizes a broad vision for biomarker inclusion, beyond typical brain-derived biomarkers, to capture and/or reflect important neurological and non-neurological pathology associated with TBI as a chronic condition. Humoral signaling molecules are explored as important signaling and regulatory drivers of these chronic conditions and their impact on function. Importantly, secondary injury cascades involved in the humoral triad are influenced by the systemic response to TBI and the development of non-neurological organ dysfunction (NNOD). Biomarkers have been successfully leveraged in other medical fields to inform pre-randomization patient selection for clinical trials, however, this practice largely has not been utilized in TBI research. As such, the applicability of the Rehabilomics research model to contemporary clinical trials and comparative effectiveness research designs for neurological and rehabilitation populations is emphasized. Potential points of intervention to modify inflammation, hormonal, or neurotrophic support through rehabilitation interventions are discussed. This article is part of the Special Issue entitled "Novel Treatments for Traumatic Brain Injury".

Late starting treadmill exercise improves spatial leaning ability through suppressing CREP/BDNF/TrkB signaling pathway following traumatic brain injury in rats

Traumatic brain injury (TBI) causes deficit in spatial learning and memory function. Physical activity ameliorates neurological dysfunction after TBI. We investigated the effect of late starting treadmill exercise on spatial learning ability in relation with cAMP-response element binding protein (CREB)/brain-derived neurotrophic factor (BDNF) signaling pathway using TBI rats. For this study, radial 8-arm maze test, TUNEL (terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling) staining, caspase-3 immunohistochemistry, and western blot for Bax, Bcl-2, BDNF, tyrosine kinase B (TrkB), CREB, and phosphorylated CREP (p-CREB) were performed. TBI was induced by an electromagnetic-controlled cortical impact. The rats in the exercise groups were scheduled to run on a treadmill for 30 min once a day for 8 weeks starting 3 weeks after TBI. TBI impaired spatial learning ability and increased caspase-3 expression in the hippocampal dentate gyrus. TBI enhanced Bax expression and suppressed Bcl-2 expression in the hip-pocampus. TBI increased BDNF and TrkB expressions, resulted in the enhancement of p-CREB/CREB ratio in the hippocampus. However, treadmill exercise improved spatial learning ability, decreased caspase-3 expression, suppressed Bax expression, and increased Bcl-2 expression. Treadmill exercise alleviated TBI-induced over-expression of BDNF and TrkB, which suppressed phosphorylation of CREB in the hippocampus. In the present study, late starting treadmill exercise improved spatial learning ability through suppressing TBI-induced activation of CREB/BDNF/TrkB signaling pathway after TBI.

Traumatic Brain Injury and Alzheimer's Disease: The Cerebrovascular Link

Traumatic brain injury (TBI) and Alzheimer's disease (AD) are devastating neurological disorders, whose complex relationship is not completely understood. Cerebrovascular pathology, a key element in both conditions, could represent a mechanistic link between Aβ/tau deposition after TBI and the development of post concussive syndrome, dementia and chronic traumatic encephalopathy (CTE). In addition to debilitating acute effects, TBI-induced neurovascular injuries accelerate amyloid β (Aβ) production and perivascular accumulation, arterial stiffness, tau hyperphosphorylation and tau/Aβ-induced blood brain barrier damage, giving rise to a deleterious feed-forward loop. We postulate that TBI can initiate cerebrovascular pathology, which is causally involved in the development of multiple forms of neurodegeneration including AD-like dementias. In this review, we will explore how novel biomarkers, animal and human studies with a focus on cerebrovascular dysfunction are contributing to the understanding of the consequences of TBI on the development of AD-like pathology.

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Cerebrovascular dysfunction (CVD) is emerging as a key element in the development of neurodegeneration after TBI.

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We propose that TBI initiates CVD, accelerating Aβ/tau deposition and leading to neurodegeneration and dementias.

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Clarifying this connection will support the development of novel biomarkers and therapeutic approaches for both TBI and AD.

Home and family in cognitive rehabilitation after brain injury: Implementation of social reserves

The focus of the present article is the home and family environment of patients suffering acquired brain injury. In order to obtain the optimal outcome of posttraumatic cognitive rehabilitation it is important (a) to obtain a sufficient intensity of rehabilitative training, (b) to achieve the maximum degree of generalization from formalized training to the daily environment of the patient, and (c) to obtain the best possible utilization of "cognitive reserves" in the form of cognitive abilities and "strategies" acquired pretraumatically. Supplementing the institution-based cognitive training with (potentially computer-based) home-based training these three goals may more easily be met. Home-based training supports a higher intensity of training. Training in the home environment also allows better utilization of cognitive strategies acquired pretraumatically and more direct transfer of training results from formalized training to activities of daily living of the patient.

Graded Aerobic Treadmill Testing in Adolescent Traumatic Brain Injury Patients

PURPOSE

To examine the safety and tolerability of clinical graded aerobic treadmill testing in recovering adolescent moderate and severe traumatic brain injury (TBI) patients referred to a multidisciplinary pediatric concussion program.

METHODS

We completed a retrospective case series of two moderate and five severe TBI patients (mean age, 17.3 years) who underwent initial Buffalo Concussion Treadmill Testing at a mean time of 71.6 days (range, 55-87) postinjury.

RESULTS

Six patients completed one graded aerobic treadmill test each and one patient underwent initial and repeat testing. There were no complications. Five initial treadmill tests were completely tolerated and allowed an accurate assessment of exercise tolerance. Two initial tests were terminated early by the treatment team because of neurological and cardiorespiratory limitations. As a result of testing, two patients were cleared for aerobic exercise as tolerated and four patients were treated with individually tailored submaximal aerobic exercise programs resulting in subjective improvement in residual symptoms and/or exercise tolerance. Repeat treadmill testing in one patient performed after 1 month of treatment with submaximal aerobic exercise prescription was suggestive of improved exercise tolerance. One patient was able to tolerate aerobic exercise following surgery for posterior glottic stenosis.

CONCLUSIONS

Preliminary results suggest that graded aerobic treadmill testing is a safe, well tolerated, and clinically useful tool to assess exercise tolerance in appropriately selected adolescent patients with TBI. Future prospective studies are needed to evaluate the effect of tailored submaximal aerobic exercise prescription on exercise tolerance and patient outcomes in recovering adolescent moderate and severe TBI patients.

Uncoupling between cerebral perfusion and oxygenation during incremental exercise in an athlete with postconcussion syndrome: a case report

High-intensity exercise may pose a risk to patients with postconcussion syndrome (PCS) when symptomatic during exertion. The case of a paralympic athlete with PCS who experienced a succession of convulsion-awakening periods and reported a marked increase in postconcussion symptoms after undergoing a graded symptom-limited aerobic exercise protocol is presented. Potential mechanisms of cerebrovascular function failure are then discussed.

Efficiency of an Active Rehabilitation Intervention in a Slow-to-Recover Paediatric Population following Mild Traumatic Brain Injury: A Pilot Study

Objective. The aim of this study was to identify whether the addition of an individualised Active Rehabilitation Intervention to standard care influences recovery of young patients who are slow-to-recover following a mTBI. Methods. Fifteen participants aged 15 ± 2 years received standard care and an individualised Active Rehabilitation Intervention which included (1) low- to high-intensity aerobic training; (2) sport-specific coordination exercises; and (3) therapeutic balance exercises. The following criteria were used to measure the resolution of signs and symptoms of mTBI: (1) absence of postconcussion symptoms for more than 7 consecutive days; (2) cognitive function corresponding to normative data; and (3) absence of deficits in coordination and balance. Results. The Active Rehabilitation Intervention lasted 49 ± 17 days. The duration of the intervention was correlated with self-reported participation ([Formula: see text]%, r = -0.792, p < 0.001). The average postconcussion symptom inventory (PCSI) score went from a total of 36.85 ± 23.21 points to 4.31 ± 5.04 points after the intervention (Z = -3.18, p = 0.001). Conclusion. A progressive submaximal Active Rehabilitation Intervention may represent an important asset in the recovery of young patients who are slow-to-recover following a mTBI.

Treatment Perspectives Based on Our Current Understanding of Concussion

Sports-related concussion also referred to in the literature as mild traumatic brain injury remains a popular area of study for physicians, neurologists, neuropsychologists, neuroimaging, athletic trainers, and researchers across the other areas of brain sciences. Treatment for concussion is an emerging area of focus with investigators seeking to improve outcomes and protect patients from the deleterious short-term and long-term consequences which have been extensively studied and identified. Broadly, current treatment strategies for athletes recovering from concussion have remained largely unchanged since early 2000s. Knowledge of the complex pathophysiology surrounding injury should improve or advance our ability to identify processes which may serve as targets for therapeutic intervention. Clinicians working with athletes recovering from sports-related concussion should have an advanced understanding of the injury cascade and also be aware of the current efforts within the research to treat concussion. In addition, how clinicians use the word "treatment" should be carefully defined and promoted so the patient is aware of the level of intervention and what stage of recovery or healing is being affected by a specific intervention. The purpose of this review is to bring together efforts across disciplines of brain science into 1 platform where clinicians can assimilate this information before making best practices decisions regarding the treatment of patients and athletes under their care.

The impact of physical therapy in patients with severe traumatic brain injury during acute and post-acute rehabilitation according to coma duration

[Purpose] The aim of study was to evaluate the impact of physical therapy on the recovery of motor and mental status in patients who sustained a severe traumatic brain injury, according to coma duration in acute and post-acute rehabilitation. [Subjects and Methods] The study population comprised patients with levels of consciousness ranging from 3 to 8 according to Glasgow Coma Scale score. The patients were divided into 2 groups based on coma duration as follows: group 1, those who were in a coma up to 1 week, and group 2, those who were in a coma for more than 2 weeks. The recovery of the patients' motor function was evaluated according to the Motor Assessment Scale and the recovery of mental status according to the Mini-Mental State Examination. [Results] The evaluation of motor and mental status recovery revealed that the patients who were in a coma up to 1 week recovered significantly better after physical therapy during the acute rehabilitation than those who were in a coma for longer than 2 weeks. [Conclusion] The recovery of motor and mental status of the patients in acute rehabilitation was significantly better for those in a coma for a shorter period.

The Impact of Previous Physical Training on Redox Signaling after Traumatic Brain Injury in Rats: A Behavioral and Neurochemical Approach

Throughout the world, traumatic brain injury (TBI) is one of the major causes of disability, which can include deficits in motor function and memory, as well as acquired epilepsy. Although some studies have shown the beneficial effects of physical exercise after TBI, the prophylactic effects are poorly understood. In the current study, we demonstrated that TBI induced by fluid percussion injury (FPI) in adult male Wistar rats caused early motor impairment (24 h), learning deficit (15 days), spontaneous epileptiform events (SEE), and hilar cell loss in the hippocampus (35 days) after TBI. The hippocampal alterations in the redox status, which were characterized by dichlorofluorescein diacetate oxidation and superoxide dismutase (SOD) activity inhibition, led to the impairment of protein function (Na(+), K(+)-adenosine triphosphatase [ATPase] activity inhibition) and glutamate uptake inhibition 24 h after neuronal injury. The molecular adaptations elicited by previous swim training protected against the glutamate uptake inhibition, oxidative stress, and inhibition of selected targets for free radicals (e.g., Na(+), K(+)-ATPase) 24 h after neuronal injury. Our data indicate that this protocol of exercise protected against FPI-induced motor impairment, learning deficits, and SEE. In addition, the enhancement of the hippocampal phosphorylated nuclear factor erythroid 2-related factor (P-Nrf2)/Nrf2, heat shock protein 70, and brain-derived neurotrophic factor immune content in the trained injured rats suggests that protein expression modulation associated with an antioxidant defense elicited by previous physical exercise can prevent toxicity induced by TBI, which is characterized by cell loss in the dentate gyrus hilus at 35 days after TBI. Therefore, this report suggests that previous physical exercise can decrease lesion progression in this model of brain damage.

Exercise and Nutritional Benefits in PD: Rodent Models and Clinical Settings

Physical exercise offers a highly effective health-endowering activity as has been evidence using rodent models of Parkinson's disease (PD). It is a particularly useful intervention in individuals employed in sedentary occupations or afflicted by a neurodegenerative disorder, such as PD. The several links between exercise and quality-of-life, disorder progression and staging, risk factors and symptoms-biomarkers in PD all endower a promise for improved prognosis. Nutrition provides a strong determinant for disorder vulnerability and prognosis with fish oils and vegetables with a mediterranean diet offering both protection and resistance. Three factors determining the effects of exercise on disorder severity of patients may be presented: (i) Exercise effects upon motor impairment, gait, posture and balance, (ii) Exercise reduction of oxidative stress, stimulation of mitochondrial biogenesis and up-regulation of autophagy, and (iii) Exercise stimulation of dopamine (DA) neurochemistry and trophic factors. Running-wheel performance, as measured by distance run by individual mice from different treatment groups, was related to DA-integrity, indexed by striatal DA levels. Finally, both nutrition and exercise may facilitate positive epigenetic outcomes, such as lowering the dosage of L-Dopa required for a therapeutic effect.

Objective Assessment of Activity in Inpatients with Traumatic Brain Injury: Initial Findings

Purpose:Use accelerometers to examine the physical activity behaviours of individuals following TBI undergoing inpatient rehabilitation.

Method:Twenty-one individuals with Traumatic brain injury (TBI) undergoing inpatient rehabilitation (9 females, 12 males;Mage = 43.8 ± 14.7 years;MGCS = 9.1 ± 4.3;Mtime since injury = 40.8 ± 22.1 days;Mlength of stay (LOS) = 30 ± 14 days) wore accelerometers for an average of 8.4 ± 2.0 consecutive days (1440 minutes/day). Activity counts (AC) were collected at 1 minute epochs and descriptive statistics were calculated to assess intensity of activity and time spent being active and sedentary.

Results:During scheduled therapy, time individuals completed an average of 161.4 ± 65.5 AC/minute, which decreased to 114.5 ± 51.3 during non-therapy time and 22.2 ± 10 when sleeping. Using population level cut points, individuals were on average considered inactive during therapy, inactive or sedentary during non-therapy time, and only one participant spent >1 minute in moderate intensity activity. The mean length of active and sedentary bouts was 9 minutes.

Discussion:Findings indicate that the amount and intensity of activity completed is low amongst individuals completing inpatient rehabilitation after TBI, with the majority considered sedentary or inactive. While the sample is small, it is important to develop and implement safe and effective strategies to increase activity levels during rehabilitation.

Physical Exercise Alleviates Health Defects, Symptoms, and Biomarkers in Schizophrenia Spectrum Disorder

Schizophrenia spectrum disorders are characterized by symptom profiles consisting of positive and negative symptoms, cognitive impairment, and a plethora of genetic, epigenetic, and phenotypic biomarkers. Assorted animal models of these disorders and clinical neurodevelopmental indicators have implicated neurodegeneration as an element in the underlying pathophysiology. Physical exercise or activity regimes--whether aerobic, resistance, or endurance--ameliorate regional brain and functional deficits not only in affected individuals but also in animal models of the disorder. Cognitive deficits, often linked to regional deficits, were alleviated by exercise, as were quality-of-life, independent of disorder staging and risk level. Apoptotic processes intricate to the etiopathogenesis of schizophrenia were likewise attenuated by physical exercise. There is also evidence of manifest benefits endowed by physical exercise in preserving telomere length and integrity. Not least, exercise improves overall health and quality-of-life. The notion of scaffolding as the outcome of physical exercise implies the "buttressing" of regional network circuits, neurocognitive domains, anti-inflammatory defenses, maintenance of telomeric integrity, and neuro-reparative and regenerative processes.

Voluntary Exercise Preconditioning Activates Multiple Antiapoptotic Mechanisms and Improves Neurological Recovery after Experimental Traumatic Brain Injury

Physical activity can attenuate neuronal loss, reduce neuroinflammation, and facilitate recovery after brain injury. However, little is known about the mechanisms of exercise-induced neuroprotection after traumatic brain injury (TBI) or its modulation of post-traumatic neuronal cell death. Voluntary exercise, using a running wheel, was conducted for 4 weeks immediately preceding (preconditioning) moderate-level controlled cortical impact (CCI), a well-established experimental TBI model in mice. Compared to nonexercised controls, exercise preconditioning (pre-exercise) improved recovery of sensorimotor performance in the beam walk task, as well as cognitive/affective functions in the Morris water maze, novel object recognition, and tail-suspension tests. Further, pre-exercise reduced lesion size, attenuated neuronal loss in the hippocampus, cortex, and thalamus, and decreased microglial activation in the cortex. In addition, exercise preconditioning activated the brain-derived neurotrophic factor pathway before trauma and amplified the injury-dependent increase in heat shock protein 70 expression, thus attenuating key apoptotic pathways. The latter include reduction in CCI-induced up-regulation of proapoptotic B-cell lymphoma 2 (Bcl-2)-homology 3-only Bcl-2 family molecules (Bid, Puma), decreased mitochondria permeabilization with attenuated release of cytochrome c and apoptosis-inducing factor (AIF), reduced AIF translocation to the nucleus, and attenuated caspase activation. Given these neuroprotective actions, voluntary physical exercise may serve to limit the consequences of TBI.

Exercise and neurologic disease

PURPOSE OF REVIEW

This article provides a practical clinical approach for the role of exercise in the treatment and management of neurologic disorders.

RECENT FINDINGS

A number of clinical studies have reported positive benefits from exercise in various neurologic disease states, suggesting that this mode of intervention should be considered as another option in clinical management.

SUMMARY

Significant evidence-based data exists confirming the positive effects of exercise in otherwise healthy populations. Good evidence also exists that physical activity may benefit people with long-term neurologic conditions. Despite this evidence, exercise is often neglected in patients with normal aging or neurologic disease progression. Neurologists should counsel patients on this therapeutic adjunct and provide specific recommendations when possible.

Decreased level of olfactory receptors in blood cells following traumatic brain injury and potential association with tauopathy

Traumatic brain injury (TBI) is a leading cause of death and disability among children and young adults in the United States. In this study, we explored whether changes in the gene expression profile of peripheral blood mononuclear cells (PBMC) may provide a clinically assessable "window" into the brain, reflecting molecular alterations following TBI that might contribute to the onset and progression of TBI clinical complications. We identified three olfactory receptor (OR) TBI biomarkers that are aberrantly down-regulated in PBMC specimens from TBI subjects. Down-regulation of these OR biomarkers in PBMC was correlated with the severity of brain injury and TBI-specific symptoms. A two- biomarker panel comprised of OR11H1 and OR4M1 provided the best criterion for segregating the TBI and control cases with 90% accuracy, 83.3% sensitivity, and 100% specificity. We found that the OR biomarkers are ectopically expressed in multiple brain regions, including the entorhinal-hippocampus system known to play an important role in memory formation and consolidation. Activation of OR4M1 led to attenuation of abnormal tau phosphorylation, possibly through JNK signaling pathway. Our results suggested that addition of the two-OR biomarker model to current diagnostic criteria may lead to improved TBI detection for clinical trials, and decreased expression of OR TBI biomarkers might be associated with TBI-induced tauopathy. Future studies exploring the physiological relevance of OR TBI biomarkers in the normal brain and in the brain following TBI will provide a better understanding of the biological mechanisms underlying TBI and insights into novel therapeutic targets for TBI.

Predicting health-related quality of life 2 years after moderate-to-severe traumatic brain injury

AIMS

To describe health-related quality of life (HRQL) 2 years after moderate-to-severe traumatic brain injury (TBI) and to assess predictors of HRQL.

MATERIALS AND METHODS

A prospective cohort study of 91 patients, aged 16-55 years, admitted with moderate-to-severe TBI to a trauma referral centre between 2005 and 2007, with follow-up at 1 and 2 years. Mean age was 31.1 (SD = 11.3) years, and 77% were men. Injury severity was evaluated by the Glasgow Coma Scale (GCS), head CT scan (using a modified Marshall Classification), Injury Severity Score (ISS) and post-traumatic amnesia (PTA). The Functional Independence Measure (FIM), Community Integration Questionnaire (CIQ), Beck Depression Inventory (BDI) and Medical Outcomes 36-item Short Form Health Survey (SF-36) were administered at follow-up visits. The main outcome measures were the Physical Component Summary (PCS) and Mental Component Summary (MCS) of the SF-36.

RESULTS

HRQL appears to be relatively stable between 1 and 2 years after injury. In the multivariate linear regression, younger age (β = -0.20, P = 0.032), more severe TBI (β = 0.28, P = 0.016), more severe overall trauma (β = 0.22, P = 0.026), higher levels of community integration (β = 0.36, P = 0.019) and higher positive change in PCS scores from 1 to 2 years (β = 0.41, P < 0.001) predicted better self-reported physical health 2 years post-TBI. Lower scores for depression (β = -0.70, P < 0.001) and a higher positive change in MCS scores (β = 0.62, P < 0.001) predicted better self-reported mental health.

CONCLUSIONS

Future interventions should focus on aspects related to HRQL that are more easily modified, such as physical functioning, home and social integration, productivity, and mental and emotional status.

Elevated plasma MCP-1 concentration following traumatic brain injury as a potential "predisposition" factor associated with an increased risk for subsequent development of Alzheimer's disease

We explored whether changes in the expression profile of peripheral blood plasma proteins may provide a clinical, readily accessible "window" into the brain, reflecting molecular alterations following traumatic brain injury (TBI) that might contribute to TBI complications. We recruited fourteen TBI and ten control civilian participants for the study, and also analyzed banked plasma specimens from 20 veterans with TBI and 20 control cases. Using antibody arrays and ELISA assays, we explored differentially-regulated protein species in the plasma of TBI compared to healthy controls from the two independent cohorts. We found three protein biomarker species, monocyte chemotactic protein-1 (MCP-1), insulin-like growth factor-binding protein-3, and epidermal growth factor receptor, that are differentially regulated in plasma specimens of the TBI cases. A three-biomarker panel using all three proteins provides the best potential criterion for separating TBI and control cases. Plasma MCP-1 contents are correlated with the severity of TBI and the index of compromised axonal fiber integrity in the frontal cortex. Based on these findings, we evaluated postmortem brain specimens from 7 mild cognitive impairment (MCI) and 7 neurologically normal cases. We found elevated MCP-1 expression in the frontal cortex of MCI cases that are at high risk for developing Alzheimer's disease. Our findings suggest that additional application of the three-biomarker panel to current diagnostic criteria may lead to improved TBI detection and more sensitive outcome measures for clinical trials. Induction of MCP-1 in response to TBI might be a potential predisposing factor that may increase the risk for development of Alzheimer's disease.

Energy intake and exercise as determinants of brain health and vulnerability to injury and disease

Evolution favored individuals with superior cognitive and physical abilities under conditions of limited food sources, and brain function can therefore be optimized by intermittent dietary energy restriction (ER) and exercise. Such energetic challenges engage adaptive cellular stress-response signaling pathways in neurons involving neurotrophic factors, protein chaperones, DNA-repair proteins, autophagy, and mitochondrial biogenesis. By suppressing adaptive cellular stress responses, overeating and a sedentary lifestyle may increase the risk of Alzheimer's and Parkinson's diseases, stroke, and depression. Intense concerted efforts of governments, families, schools, and physicians will be required to successfully implement brain-healthy lifestyles that incorporate ER and exercise.

Treatment of post-traumatic epilepsy

OPINION STATEMENT

Post-traumatic epilepsy (PTE) due to traumatic brain injury is a diagnosis with multifactorial causes, diverse clinical presentations, and an evolving concept of management. Due to sports injuries, work-related injuries, vehicular accidents, and wartime combat, there is rising demand to understand the epidemiology, pathophysiology, diagnosis, prognosis, and treatment of PTE. PTE could occur at any time after injury and up to decades post-injury. The frontal and temporal lobes are the most commonly affected regions, and the resulting epilepsy syndrome is typically localization related. PTE should be actively considered as a diagnosis in any patient with a history of head trauma and episodic neurologic compromise regardless of how temporally remote the trauma occurred. The standard work-up includes a thorough history, neurological examination, neuroimaging, and electroencephalogram. Psychogenic nonepileptic seizures have a high comorbidity with seizures and need to be carefully excluded. PTE can spontaneously remit. For patients who do not go into remission, treatment for confirmed PTE includes antiepileptics, vagal nerve stimulator, and, when appropriate, surgical resection of an epileptogenic lesion. Lifestyle modification and counseling are critical for patients with PTE and should be routinely included in clinical management. The published evidence on the efficacy of various treatment modalities specific to PTE consists largely of retrospective studies and case reports. Despite a unique pathogenesis, the majority of current care parameters for PTE parallel those of standard care for localization-related epilepsy. The potential and need for rigorous clinical research in PTE continue to be in great demand.