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Proper brain functioning is responsible for our feelings, behavior, and thinking. However, an injury to the brain can disrupt brain function, which can affect our emotions and behaviors. A traumatic brain injury (TBI) can be a one-time severe injury to the brain, or repeated, milder injuries. Scientists have observed that, after TBI, people are frequently sad and have difficulty concentrating. These symptoms are referred to as post-traumatic depression (PTD). PTD can affect school performance and daily activities. It is therefore important to notice any signs of PTD. If signs of PTD are present, individuals should seek help from a professional. PTD is treatable and, with adequate treatment, individuals with PTD can gradually recover their normal functioning.

Mild traumatic brain injury (mTBI) or concussion accounts for the bulk of all head injuries and represents a major health concern. Although an mTBI event may not manifest in neurobehavioral impairment, repeated injuries, known as repeated mTBI (rmTBI), can result in a cumulative effect that may progress to long-term cognitive and functional deficits. To date, there is no FDA-approved drug for TBI in general and rmTBI in particular. In previous studies, we have demonstrated the neuroprotective role of mitoquinone (MitoQ), a mitochondrial antioxidant, in an open head injury model and a model of repeated mild TBI (rmTBI) at a chronic time point (30 days). In this work, we set out to assess the neuroprotective potential of MitoQ at acute (3 days) and subacute time points (7 days) post-injury in a controlled cortical impact model of rmTBI. C57BL/6 male mice were injected intraperitoneally with MitoQ (5 mg/kg) one hour after the first mTBI, and three days after the first injury in both the 3-day and 7-day MitoQ + rmTBI subgroups, with an additional injection four days after the second injection in the 7-day group. Cognitive function was evaluated using the Morris water maze (MWM) while gross and fine motor functions were evaluated by the pole climbing, grip strength, and ladder rung tests. Dihydroethidium (DHE) staining was performed to evaluate oxidative stress while qRT-PCR was used to measure the gene expression of different antioxidant enzymes. Also, immunofluorescence staining was performed on brain tissue to assess the degree of microgliosis and astrocytosis. Our results showed that MitoQ conferred significant protection on days 3 and 7 post-injury against fine motor function impairment induced by rmTBI. Moreover, MitoQ enhanced cognitive function and reduced astrogliosis, microgliosis, and levels of oxidative stress on day 7 post-injury. However, antioxidant gene expression generally remained unaffected. In light of our results, MitoQ administration may be considered a preventive approach that helps to alleviate the neurological manifestations associated with rmTBI early before symptoms progress to long-term deficits.

Traumatic Brain Injury (TBI) is one of the leading causes of death and disability worldwide. Aspirin (ASA) and clopidogrel (CLOP) are antiplatelet agents that inhibit platelet aggregation. They are implicated in worsening the intracerebral haemorrhage (ICH) risk post-TBI. However, antiplatelet drugs may also exert a neuroprotective effect post-injury. We determined the impact of ASA and CLOP treatment, alone or in combination, on ICH and brain damage in an experimental rat TBI model. We assessed changes in platelet aggregation and measured serum thromboxane by enzyme immune assay. We also explored a panel of brain damage and apoptosis biomarkers by immunoblotting. Rats were treated with ASA and/or CLOP for 48 h prior to TBI and sacrificed 48 h post-injury. In rats treated with antiplatelet agents prior to TBI, platelet aggregation was completely inhibited, and serum thromboxane was significantly decreased, compared to the TBI group without treatment. TBI increases UCHL-1 and GFAP, but decreases hexokinase expression compared to the non-injured controls. All groups treated with antiplatelet drugs prior to TBI had decreased UCH-L1 and GFAP serum levels compared to the TBI untreated group. Furthermore, the ASA and CLOP single treatments increased the hexokinase serum levels. We confirmed that αII-spectrin cleavage increased post-TBI, with the highest cleavage detected in CLOP-treated rats. Aspirin and/or CLOP treatment prior to TBI is a double-edged sword that exerts a dual effect post-injury. On one hand, ASA and CLOP single treatments increase the post-TBI ICH risk, with a further detrimental effect from the ASA + CLOP treatment. On the other hand, ASA and/or CLOP treatments are neuroprotective and result in a favourable profile of TBI injury markers. The ICH risk and the neuroprotection benefits from antiplatelet therapy should be weighed against each other to ameliorate the management of TBI patients.

Traumatic brain injury (TBI) is a major cause of disability and death. Mild TBI (mTBI) constitutes ~75% of all TBI cases. Repeated exposure to mTBI (rmTBI), leads to the exacerbation of the symptoms compared to single mTBI. To date, there is no FDA-approved drug for TBI or rmTBI. This research aims to investigate possible rmTBI neurotherapy by targeting TBI pathology-related mechanisms. Oxidative stress is partly responsible for TBI/rmTBI neuropathologic outcomes. Thus, targeting oxidative stress may ameliorate TBI/rmTBI consequences. In this study, we hypothesized that mitoquinone (MitoQ), a mitochondria-targeted antioxidant, would ameliorate TBI/rmTBI associated pathologic features by mitigating rmTBI-induced oxidative stress. To model rmTBI, C57BL/6 mice were subjected to three concussive head injuries. MitoQ (5 mg/kg) was administered intraperitoneally to rmTBI+MitoQ mice twice per week over one month. Behavioral and cognitive outcomes were assessed, 30 days following the first head injury, using a battery of behavioral tests. Immunofluorescence was used to assess neuroinflammation and neuronal integrity. Also, qRT-PCR was used to evaluate the expression levels of antioxidant enzymes. Our findings indicated that MitoQ alleviated fine motor function and learning impairments caused by rmTBI. Mechanistically, MitoQ reduced astrocytosis, microgliosis, dendritic and axonal shearing, and increased the expression of antioxidant enzymes. MitoQ administration following rmTBI may represent an efficient approach to ameliorate rmTBI neurological and cellular outcomes with no observable side effects.

Post-traumatic epilepsy (PTE) and neurocognitive deficits are devastating sequelae of head injuries that are common in adolescents. Investigating desperately needed treatments is hindered by the difficulties in inducing PTE in rodents and the lack of established immature rat models of pediatric PTE. Hemorrhage is a significant risk factor for PTE, but compared to humans, rats are less prone to bleeding because of their rapid blood coagulation system. In this study, we promoted bleeding in the controlled cortical impact (CCI) closed-head injury model with a 20 min pre-impact 600 IU/kg intraperitoneal heparin injection in postnatal day 35 (P35) periadolescent rats, given the preponderance of such injuries in this age group. Temporo-parietal CCI was performed post-heparin (HTBI group) or post-saline (TBI group). Controls were subjected to sham procedures following heparin or saline administration. Continuous long-term EEG monitoring was performed for 3 months post-CCI. Sensorimotor testing, the Morris water maze, and a modified active avoidance test were conducted between P80 and P100. Glial fibrillary acidic protein (GFAP) levels and neuronal damage were also assessed. Compared to TBI rats, HTBI rats had persistently higher EEG spiking and increased hippocampal GFAP levels (p &lt, 0.05). No sensorimotor deficits were detected in any group. Compared to controls, both HTBI and TBI groups had a long-term hippocampal neuronal loss (p &lt, 0.05), as well as contextual and visuospatial learning deficits (p &lt, 0.05). The hippocampal astrogliosis and EEG spiking detected in all rats subjected to our hemorrhage-promoting procedure suggest the emergence of hyperexcitable networks and pave the way to a periadolescent PTE rat model.

Traumatic brain injury (TBI) is a major health concern worldwide and is classified based on severity into mild, moderate, and severe. The mechanical injury in TBI leads to a metabolic and ionic imbalance, which eventually leads to excessive production of reactive oxygen species (ROS) and a state of oxidative stress. To date, no drug has been approved by the food and drug administration (FDA) for the treatment of TBI. Nevertheless, it is thought that targeting the pathology mechanisms would alleviate the consequences of TBI. For that purpose, antioxidants have been considered as treatment options in TBI and were shown to have a neuroprotective effect. In this review, we will discuss oxidative stress in TBI, the history of antioxidant utilization in the treatment of TBI, and we will focus on two novel antioxidants, mitoquinone (MitoQ) and edaravone. MitoQ can cross the blood brain barrier and cellular membranes to accumulate in the mitochondria and is thought to activate the Nrf2/ARE pathway leading to an increase in the expression of antioxidant enzymes. Edaravone is a free radical scavenger that leads to the mitigation of damage resulting from oxidative stress with a possible association to the activation of the Nrf2/ARE pathway as well.

The central nervous system (CNS) injury, encompassing both traumatic brain injury (TBI) and spinal cord injury (SCI) injury, is a global public health burden and a major cause of disability and mortality. Recent studies have highlighted the effectiveness of applying standardized diagnosis and assessment procedures in establishing evidence-based interventions to minimize the dramatic consequences of traumatic CNS injury. There is an increasing interest in the effects as well as the utility of autoantibodies on human pathobiology. In the field of CNS trauma, autoantibodies have the potential roles as biomarkers as well as guides for neurotherapy. Several autoantibodies have been studied for their neuroprotective and/or neurotoxic implications during CNS injury for their diagnostic and prognostic tools. Here, we provide an overview of the immune responses following CNS trauma and highlight the role of autoimmunity following CNS injury. Furthermore, we provide perspectives on the potential roles of autoantibodies as pathological components and as candidate diagnostic or prognostic markers for detecting and assessing CNS injury. Finally, we discuss the detrimental role that B cell activation plays during CNS injury as it offers particular therapeutic opportunities.

Edaravone is a potent free-radical scavenger that has been in the market for more than 30 years. It was originally developed in Japan to treat strokes and has been used there since 2001. Aside from its anti-oxidative effects, edaravone demonstrated beneficial effects on proinflammatory responses, nitric oxide production, and apoptotic cell death. Interestingly, edaravone has shown neuroprotective effects in several animal models of diseases other than stroke. In particular, edaravone administration was found to be effective in halting amyotrophic lateral sclerosis (ALS) progression during the early stages. Accordingly, after its success in Phase III clinical studies, edaravone has been approved by the FDA as a treatment for ALS patients. Considering its promises in neurological disorders and its safety in patients, edaravone is a drug of interest that can be repurposed for traumatic brain injury (TBI) treatment. Drug repurposing is a novel approach in drug development that identifies drugs for purposes other than their original indication. This review presents the biochemical properties of edaravone along with its effects on several neurological disorders in the hope that it can be adopted for treating TBI patients.

Background: Traumatic Brain Injury (TBI) is the most prevalent of all head injuries, and based on the severity of the injury, it may result in chronic neurologic and cognitive deficits. Microglia play an essential role in homeostasis and diseases of the central nervous system. We hypothesize that microglia may play a beneficial or detrimental role in TBI depending on their state of activation and duration.Methods: In the present study, we evaluated whether TBI results in a spatiotemporal change in microglia phenotype and whether it affects sensory-motor or learning and memory functions in male C57BL/6 mice. We used a panel of neurological and behavioral tests and a multi-color flow cytometry-based data analysis followed by unsupervised clustering to evaluate isolated microglia from injured brain tissue. Results: We characterized several microglial phenotypes and their association with cognitive deficits. TBI results in a spatiotemporal increase in highly activated microglia that correlated negatively with spatial learning and memory at 35 days post-injury.Conclusions: These observations could define therapeutic windows and accelerate translational research to improve patient outcomes.