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Cells are complex structures that are held together by a thread-like web known as the cytoskeleton. Tiny tubes called microtubules are a major part of the cytoskeleton. Microtubules can be assembled, disassembled, and reassembled again like Lego bricks. Microtubules are especially abundant in the nerve cells of the brain. To do their jobs, microtubules call upon special helpers known as tau proteins, which keep the microtubules from crumbling by attaching themselves to the surface of the tubes. Unfortunately, tau helpers may sometimes quit their jobs and become troublemakers in the cell. The result is the unraveling of the microtubules, the destruction of the cytoskeleton, and the eventual death of the cell. A serious disease that arises because of the malfunctioning of tau proteins is called a tauopathy. In this article, we will describe the function of tau proteins and explain what happens when they turn against the cell.

Glial fibrillary acidic protein (GFAP) is the major intermediate filament III protein of astroglia cells which is upregulated in traumatic brain injury (TBI). Here we reported that GFAP is truncated at both the C- and N-terminals by cytosolic protease calpain to GFAP breakdown products (GBDP) of 46-40K then 38K following pro-necrotic (A23187) and pro-apoptotic (staurosporine) challenges to primary cultured astroglia or neuron-glia mixed cells. In addition, with another pro-apoptotic challenge (EDTA) where caspases are activated but not calpain, GFAP was fragmented internally, generating a C-terminal GBDP of 20 kDa. Following controlled cortical impact in mice, GBDP of 46-40K and 38K were formed from day 3 to 28 post-injury. Purified GFAP protein treated with calpain-1 and -2 generates (i) major N-terminal cleavage sites at A-56*A-61 and (ii) major C-terminal cleavage sites at T-383*Q-388, producing a limit fragment of 38K. Caspase-6 treated GFAP was cleaved at D-78/R-79 and D-225/A-226, where GFAP was relatively resistant to caspase-3. We also derived a GBDP-38K N-terminal-specific antibody which only labels injured astroglia cell body in both cultured astroglia and mouse cortex and hippocampus after TBI. As a clinical translation, we observed that CSF samples collected from severe human TBI have elevated levels of GBDP-38K as well as two C-terminally released GFAP peptides (DGEVIKES and DGEVIKE). Thus, in addition to intact GFAP, both the GBDP-38K as well as unique GFAP released C-terminal proteolytic peptides species might have the potential in tracking brain injury progression.

Traumatic brain injury (TBI) has the highest incidence of all common neurological disorders, and poses a substantial public health burden. TBI is increasingly documented not only as an acute condition but also as a chronic disease with long-term consequences, including an increased risk of late-onset neurodegeneration. The first Lancet Neurology Commission on TBI, published in 2017, called for a concerted effort to tackle the global health problem posed by TBI. Since then, funding agencies have supported research both in high-income countries (HICs) and in low-income and middle-income countries (LMICs). In November 2020, the World Health Assembly, the decision-making body of WHO, passed resolution WHA73.10 for global actions on epilepsy and other neurological disorders, and WHO launched the Decade for Action on Road Safety plan in 2021. New knowledge has been generated by large observational studies, including those conducted under the umbrella of the International Traumatic Brain Injury Research (InTBIR) initiative, established as a collaboration of funding agencies in 2011. InTBIR has also provided a huge stimulus to collaborative research in TBI and has facilitated participation of global partners. The return on investment has been high, but many needs of patients with TBI remain unaddressed. This update to the 2017 Commission presents advances and discusses persisting and new challenges in prevention, clinical care, and research.

Traumatic brain injury is increasingly common in older individuals. Older age is one of the strongest predictors for poor prognosis after brain trauma, a phenomenon driven by the presence of extra-cranial comorbidities as well as pre-existent pathologies associated with cognitive impairment and brain volume loss (such as cerebrovascular disease or age-related neurodegeneration). Furthermore, ageing is associated with a dysregulated immune response, which includes attenuated responses to infection and vaccination, and a failure to resolve inflammation leading to chronic inflammatory states. In traumatic brain injury, where the immune response is imperative for the clearance of cellular debris and survey of the injured milieu, an appropriate self-limiting response is vital to promote recovery. Currently, our understanding of age-related factors that contribute to the outcome is limited; but a more complete understanding is essential for the development of tailored therapeutic strategies to mitigate the consequences of traumatic brain injury. Here we show greater functional deficits, white matter abnormalities and worse long-term outcomes in aged compared with young C57BL/6J mice after either moderate or severe traumatic brain injury. These effects are associated with altered systemic, meningeal and brain tissue immune response. Importantly, the impaired acute systemic immune response in the mice was similar to the findings observed in our clinical cohort. Traumatic brain-injured patient cohort over 70 years of age showed lower monocyte and lymphocyte counts compared with those under 45 years. In mice, traumatic brain injury was associated with alterations in peripheral immune subsets, which differed in aged compared with adult mice. There was a significant increase in transcription of immune and inflammatory genes in the meninges post-traumatic brain injury, including monocyte/leucocyte-recruiting chemokines. Immune cells were recruited to the region of the dural injury, with a significantly higher number of CD11b+ myeloid cells in aged compared with the adult mice. In brain tissue, when compared with the young adult mice, we observed a more pronounced and widespread reactive astrogliosis 1 month after trauma in aged mice, sustained by an early and persistent induction of proinflammatory astrocytic state. These findings provide important insights regarding age-related exacerbation of neurological damage after brain trauma.

Background Several studies have reported an association between serum biomarker values and functional outcome following traumatic brain injury. We aimed to examine the incremental (added) prognostic value of serum biomarkers over demographic, clinical, and radiological characteristics and over established prognostic models, such as IMPACT and CRASH, for prediction of functional outcome. Methods We used data from the Collaborative European NeuroTrauma Effectiveness Research in Traumatic Brain Injury (CENTER-TBI) core study. We included patients aged 14 years or older who had blood sampling within 24 h of injury, results from a CT scan, and outcome assessment according to the Glasgow Outcome Scale-Extended (GOSE) at 6 months. Amounts in serum of six biomarkers (S100 calcium-binding protein B, neuron-specific enolase, glial fibrillary acidic protein, ubiquitin C-terminal hydrolase L1 [UCH-L1], neurofilament protein-light, and total tau) were measured. The incremental prognostic value of these biomarkers was determined separately and in combination. The primary outcome was the GOSE 6 months after injury. Incremental prognostic value, using proportional odds and a dichotomised analysis, was assessed by delta C-statistic and delta R-2 between models with and without serum biomarkers, corrected for optimism with a bootstrapping procedure. Findings Serum biomarker values and 6-month GOSE were available for 2283 of 4509 patients. Higher biomarker levels were associated with worse outcome. Adding biomarkers improved the C-statistic by 0 center dot 014 (95% CI 0 center dot 009-0 center dot 020) and R-2 by 4 center dot 9% (3 center dot 6-6 center dot 5) for predicting GOSE compared with demographic, clinical, and radiological characteristics. UCH-L1 had the greatest incremental prognostic value. Adding biomarkers to established prognostic models resulted in a relative increase in R-2 of 48-65% for IMPACT and 30-34% for CRASH prognostic models. Interpretation Serum biomarkers have incremental prognostic value for functional outcome after traumatic brain injury. Our findings support integration of biomarkers-particularly UCH-L1-in established prognostic models.

This study aims to examine the cytotoxicity mechanisms of synthetic cathinone (bath salts) on rat primary cultured neurons and primary astroglial cells, and to assess their neurobehavioral effects on mice. We administered methylenedioxypyrovalerone (MDPV) to both rat primary cultured neurons and primary astroglial cells to assess cell injury. We also analyzed the effects of MDPV on these cell cultures using immunocytochemistry. We utilized western blotting to assess the breakdown of αII-spectrin and glial fibrillary acidic protein (GFAP) induced by MDPV. The western blotting experiment also included calpain and caspase inhibitors (SNJ1945 and Z-D-DCB, respectively) and pro-apoptotic and pro-necrotic agents (Staurosporine and calcium ionophore A23187, respectively). Lastly, we assessed MDPV’s effects on behavioral effects using rotarod, locomotor activity, elevated plus maze, Morris water maze, forced swimming, and open field tests. MDPV caused a dose-dependent release of LDH in both cerebrocortical neuron-astroglia mixed cultures and primary astroglial cultures. MDPV also caused neurite breakages and astroglial process retraction on immunocytochemistry. Lastly, MDPV induced αII-spectrin breakdown in western blotting experiments. Co-administration of calpain and caspase inhibitors reduced the degradation of αII-spectrin and GFAP. MDPV administration also increased anxiety-like behavior and locomotor activity in the mice. Synthetic cathinones, which share structural similarities with methamphetamine, also induce significant neurotoxic effects and neurobehavioral effects on rodent models. These neurotoxic effects are likely mediated by calpain and caspase-induced apoptosis and necrosis, while astroglial death is likely only due to calpain activation. Therefore, further research may focus on pharmacological interventions targeting these pathways to mitigate the cytotoxic impact of cathinones in humans.

Key Points Question Is posttraumatic epilepsy (PTE) associated with unfavorable functional outcomes after traumatic brain injury (TBI)? Findings In this cohort study that included 3296 individuals, the incidence of self-reported diagnosis of PTE at 1 year after injury among individuals who had experienced TBI was 2.8%. Patients with PTE had worse outcome scores at 1 year after injury compared with those without PTE, even after accounting for injury severity and neuroimaging findings on cranial computed tomography. Meaning These findings suggest that PTE is a significant sequela of TBI with adverse associations with recovery., This cohort study assesses the incidence, risk factors, and functional outcomes associated with self-reported posttraumatic epilepsy in patients with traumatic brain injury., Importance Posttraumatic epilepsy (PTE) is a recognized sequela of traumatic brain injury (TBI), but the long-term outcomes associated with PTE independent of injury severity are not precisely known. Objective To determine the incidence, risk factors, and association with functional outcomes and self-reported somatic, cognitive, and psychological concerns of self-reported PTE in a large, prospectively collected TBI cohort. Design, Setting, and Participants This multicenter, prospective cohort study was conducted as part of the Transforming Research and Clinical Knowledge in Traumatic Brain Injury study and identified patients presenting with TBI to 1 of 18 participating level 1 US trauma centers from February 2014 to July 2018. Patients with TBI, extracranial orthopedic injuries (orthopedic controls), and individuals without reported injuries (eg, friends and family of participants; hereafter friend controls) were prospectively followed for 12 months. Data were analyzed from January 2020 to April 2021. Exposure Demographic, imaging, and clinical information was collected according to TBI Common Data Elements. Incidence of self-reported PTE was assessed using the National Institute of Neurological Disorders and Stroke Epilepsy Screening Questionnaire (NINDS-ESQ). Main Outcomes and Measures Primary outcomes included Glasgow Outcome Scale Extended, Rivermead Cognitive Metric (RCM; derived from the Rivermead Post Concussion Symptoms Questionnaire), and the Brief Symptom Inventory-18 (BSI). Results Of 3296 participants identified as part of the study, 3044 met inclusion criteria, and 1885 participants (mean [SD] age, 41.3 [17.1] years; 1241 [65.8%] men and 644 [34.2%] women) had follow-up information at 12 months, including 1493 patients with TBI; 182 orthopedic controls, 210 uninjured friend controls; 41 patients with TBI (2.8%) and no controls had positive screening results for PTE. Compared with a negative screening result for PTE, having a positive screening result for PTE was associated with presenting Glasgow Coma Scale score (8.1 [4.8] vs.13.5 [3.3]; P

Background: The burden of traumatic brain injury (TBI) poses a large public health and societal problem, but the characteristics of patients and their care pathways in Europe are poorly understood. We aimed to characterise patient case-mix, care pathways, and outcomes of TBI. Methods: CENTER-TBI is a Europe-based, observational cohort study, consisting of a core study and a registry. Inclusion criteria for the core study were a clinical diagnosis of TBI, presentation fewer than 24 h after injury, and an indication for CT. Patients were differentiated by care pathway and assigned to the emergency room (ER) stratum (patients who were discharged from an emergency room), admission stratum (patients who were admitted to a hospital ward), or intensive care unit (ICU) stratum (patients who were admitted to the ICU). Neuroimages and biospecimens were stored in repositories and outcome was assessed at 6 months after injury. We used the IMPACT core model for estimating the expected mortality and proportion with unfavourable Glasgow Outcome Scale Extended (GOSE) outcomes in patients with moderate or severe TBI (Glasgow Coma Scale [GCS] score ≤12). The core study was registered with ClinicalTrials.gov, number NCT02210221, and with Resource Identification Portal (RRID: SCR_015582). Findings: Data from 4509 patients from 18 countries, collected between Dec 9, 2014, and Dec 17, 2017, were analysed in the core study and from 22 782 patients in the registry. In the core study, 848 (19%) patients were in the ER stratum, 1523 (34%) in the admission stratum, and 2138 (47%) in the ICU stratum. In the ICU stratum, 720 (36%) patients had mild TBI (GCS score 13–15). Compared with the core cohort, the registry had a higher proportion of patients in the ER (9839 [43%]) and admission (8571 [38%]) strata, with more than 95% of patients classified as having mild TBI. Patients in the core study were older than those in previous studies (median age 50 years [IQR 30–66], 1254 [28%] aged >65 years), 462 (11%) had serious comorbidities, 772 (18%) were taking anticoagulant or antiplatelet medication, and alcohol was contributory in 1054 (25%) TBIs. MRI and blood biomarker measurement enhanced characterisation of injury severity and type. Substantial inter-country differences existed in care pathways and practice. Incomplete recovery at 6 months (GOSE

Acute spinal cord injury (SCI) results in catastrophic neurological impairment. We aimed to examine the temporal profile and severity correlation of biomarkers, and their relationship with the American Spinal Injury Association Scale (AIS) improvement in human SCI. 15 SCI and 10 non-SCI healthy subjects were classified according to the initial and discharge AIS grade. Serial cerebrospinal fluid (CSF) and serum samples were collected. Spectrin breakdown products (SBDP) 150, SBDP145, glial fibrillary acidic protein (GFAP), and GFAP breakdown product (GBDP) 38/44K were found to be elevated in the acute phase CSF samples in SCI patients on immunoblotting. SBDP150, ubiquitin C-terminal hydrolase-L1 (UCH-L1), GFAP, S100B, neurofilament light chain protein (NF-L), Tau & interleukin (IL) -6 were elevated in the acute phase CSF and serum samples on ELISA. CSF SBDP150, UCH-L1, GFAP, S100B and Tau were seen to peak on day 1 after injury, while CSF IL-6 and NF-L peaked on day 5. Serum SBDP150, IL-6, S100B, GFAP, UCHL-1 and Tau peaked on day 1, while serum NF-L peaked on day 5 post-injury. CSF alpha II-spectrin, SBDP150/145, and GBDP 44-38K levels (by immunoblots), CSF SBDP150, S100B, GFAP, UCHL-1 and Tau (ELISA) and serum UCHL-1 and Tau (ELISA) at specific time points showed SCI severity-correlation. CSF SBDP150, GFAP, and Tau and serum UCHL-1 and Tau (ELISA) were seen to have the best correlation with the severity at discharge. Receiver Operating Characteristic Curve analysis showed that CSF and serum biomarkers (SBDP150, IL-6, S100B, GFAP, NF-L, UCHL-1 and Tau) were associated with the severity of SCI.

Traumatic brain injury (TBI) is a major neurological disorder without FDA-approved therapies. In this study, we have examined the concept that TBI might trigger global brain proteolysis in the acute post-injury phase. Thus, we conducted a systemic proteolytic peptidomics analysis using acute cerebrospinal fluid (CSF) samples from TBI patients and normal control samples. We employed ultrafiltration-based low molecular weight (LMW; 10 kDa) peptide enrichment, coupled with nano-reversed-phase liquid chromatography/tandem mass spectrometry analysis, followed with orthogonal quantitative immunoblotting-based protein degradation analysis. We indeed identified novel patterns of injury-dependent proteolytic peptides derived from neuronal components (pre- and post-synaptic terminal, dendrites, axons), extracellular matrix, oligodendrocytes, microglial cells, and astrocytes. Among these, post-synaptic protein neurogranin was identified for the first time converted to neurogranin peptides including neurogranin peptide (aa 16-64) that is phosphorylated at Ser-36/48 (P-NG-fragment) in acute human TBI CSF samples vs. normal control with a receiver operating characteristic area under the curve of 0.957. We also identified detailed processing of astroglia protein (vimentin) and oligodendrocyte protein (MBP and Golli-MBP) to protein breakdown products (BDPs) and/or LMW proteolytic peptides after TBI. In addition, using MS/MS selected reaction monitoring method, two C-terminally released MBP peptides TQDENPVVHFF and TQDENPVVHF were found to be elevated in acute and subacute TBI CSF samples as compared to their normal control counterparts. These findings imply that future therapeutic strategies might be placed on the suppression of brain proteolysis as a target. The endogenous proteolytic peptides discovered in human TBI biofluid could represent useful diagnostic and monitoring tools for TBI.

The use of methamphetamine (METH) is a growing worldwide epidemic that bears grave societal implications. METH is known to exert its neurotoxic effects on the dopaminergic and serotonergic systems of the brain. In addition to this classical studied mechanism of damage, findings from our laboratory and others have shown that acute METH treatment and mechanical injury, i.e. traumatic brain injury (TBI), share common cell injury mechanism(s). Since neuro-inflammation is a signature event in TBI, we hypothesize that certain cytokine levels might also be altered in rat brain exposed to an acute METH insult. In this study, using a cytokine antibody array chip, we evaluated the serum levels of 19 cytokines in rats 24 h after exposure to a 40 mg/kg acute regimen of METH. Data were compared to rats subjected to experimental TBI using the controlled cortical impact (CCI) injury model and saline controls. Sandwich ELISA method was used to further validate some of the findings obtained from the antibody cytokine array. We confirmed that three major inflammatory-linked cytokines (IL-1β, IL-6, and IL-10) were elevated in the METH and TBI groups compared to the saline group. Such finding suggests the involvement of an inflammatory process in these brain insults, indicating that METH use is, in fact, a stressor to the immune system where systemic involvement of an altered cytokine profile may play a major role in mediating chemical brain injury after METH use.

OBJECTIVE: The aim of this paper was to evaluate the prevalence of postconcussive symptoms and their relation to health-related quality of life (HRQOL) in pediatric and adolescent patients with mild traumatic brain injury (mTBI) who received head CT imaging during initial assessment. METHODS: Patients aged between 5 and 21 years with mTBI (Glasgow Coma Scale scores 13-15) and available Rivermead Post Concussion Questionnaire (RPQ) at 6 months of follow-up in the multicenter, prospectively collected CENTER-TBI (Collaborative European NeuroTrauma Effectiveness Research in TBI) study were included. The prevalence of postconcussive symptoms was assessed, and the occurrence of postconcussive syndrome (PSC) based on the ICD-10 criteria, was analyzed. HRQOL was compared in patients with and without PCS using the Quality of Life after Brain Injury (QOLIBRI) questionnaire. RESULTS: A total of 196 adolescent or pediatric mTBI patients requiring head CT imaging were included. High-energy trauma was prevalent in more than half of cases (54%), abnormalities on head CT scans were detected in 41%, and admission to the regular ward or intensive care unit was necessary in 78%. Six months postinjury, 36% of included patients had experienced at least one moderate or severe symptom on the RPQ. PCS was present in 13% of adolescents and children when considering symptoms of at least moderate severity, and those patients had significantly lower QOLIBRI total scores, indicating lower HRQOL, compared with young patients without PCS (57 vs 83 points, p < 0.001). CONCLUSIONS: Adolescent and pediatric mTBI patients requiring head CT imaging show signs of increased trauma severity. Postconcussive symptoms are present in up to one-third of those patients, and PCS can be diagnosed in 13% 6 months after injury. Moreover, PCS is significantly associated with decreased HRQOL., Funding Agencies: OneMind (USA) Hannelore Kohl Stiftung (Germany)

Using the appropriate model for testing neurological symptoms in rats is essential for the assessment of functional outcome. A number of tests have been developed to quantify the severity of neurological deficits. These tests should meet criteria such as validity, specificity, sensitivity, and utility. Although analysis of motor function shows homology in primates and rodents, the total neurological exam scores may not always reflect the clinical outcome. Therefore, the selection of the appropriate tests has critical importance when evaluating therapeutic strategies. This chapter describes Toklu's modified neurological exam score method which can be used practically to assess neurological symptoms following traumatic brain injury (TBI) and stroke. The method is a combination of balance, muscle strength, coordination, and reflex.

Summary Background After traumatic brain injury (TBI), plasma concentration of glial fibrillary acidic protein (GFAP) correlates with intracranial injury visible on CT scan. Some patients with suspected TBI with normal CT findings show pathology on MRI. We assessed the discriminative ability of GFAP to identify MRI abnormalities in patients with normal CT findings. Methods TRACK-TBI is a prospective cohort study that enrolled patients with TBI who had a clinically indicated head CT scan within 24 h of injury at 18 level 1 trauma centres in the USA. For this analysis, we included patients with normal CT findings (Glasgow Coma Scale score 13–15) who consented to venepuncture within 24 h post injury and who had an MRI scan 7–18 days post injury. We compared MRI findings in these patients with those of orthopaedic trauma controls and healthy controls recruited from the study sites. Plasma GFAP concentrations (pg/mL) were measured using a prototype assay on a point-of-care platform. We used receiver operating characteristic (ROC) analysis to evaluate the discriminative ability of GFAP for positive MRI scans in patients with negative CT scans over 24 h (time between injury and venepuncture). The primary outcome was the area under the ROC curve (AUC) for GFAP in patients with CT-negative and MRI-positive findings versus patients with CT-negative and MRI-negative findings within 24 h of injury. The Dunn Kruskal–Wallis test was used to compare GFAP concentrations between MRI lesion types with Benjamini–Hochberg correction for multiple comparisons. This study is registered with ClinicalTrials.gov , number NCT02119182 . Findings Between Feb 26, 2014, and June 15, 2018, we recruited 450 patients with normal head CT scans (of whom 330 had negative MRI scans and 120 had positive MRI scans), 122 orthopaedic trauma controls, and 209 healthy controls. AUC for GFAP in patients with CT-negative and MRI-positive findings versus patients with CT-negative and MRI-negative findings was 0·777 (95% CI 0·726–0·829) over 24 h. Median plasma GFAP concentration was highest in patients with CT-negative and MRI-positive findings (414·4 pg/mL, 25–75th percentile 139·3–813·4), followed by patients with CT-negative and MRI-negative findings (74·0 pg/mL, 17·5–214·4), orthopaedic trauma controls (13·1 pg/mL, 6·9–20·0), and healthy controls (8·0 pg/mL, 3·0–14·0; all comparisons between patients with CT-negative MRI-positive findings and other groups p Interpretation Analysis of blood GFAP concentrations using prototype assays on a point-of-care platform within 24 h of injury might improve detection of TBI and identify patients who might need subsequent MRI and follow-up. Funding National Institute of Neurological Disorders and Stroke and US Department of Defense.

This new book volume, simply titled Neurotrauma, aims to bring together the latest clinical practice and research in the field of two forms of trauma to the central nervous system: namely, traumatic brain injury (TBI) and spinal cord injury (SCI). Nationally, more 1.9 million Americans sustain a TBI annually. In parallel, there are an estimated 12,000 new cases of SCI in the United States annually. In addition, approximately 1.2 million people live with paralysis due to SCI. In recent years, dramatic advancements in the field have resulted in much improved outcomes for patients and higher standards of care. This volume brings together the latest research and clinical practice in the treatment of neurotrauma in a comprehensive but easy-to-follow format. Our target readership is intentionally broad. It includes clinicians who are involved in caring for TBI in the emergency room, hospital, or neurointensive care unit or during patient rehabilitation; clinical research professionals; research nurses; and nonclinical academic researchers, such as research professors, research scientists, medical students, graduate students, and nurse specialists, as well as biomedical industry R&D scientists and clinical associates. As editor of this volume, I want all readers to find a chapter or section on almost all aspects related to TBI or SCI. I also hope that they will encounter some areas they might be already familiar with. Yet, at the same time, I hope that they will also discover or rediscover other less familiar areas in neurotrauma that they have always wanted to learn more about. Last, I want to make this volume as layman-like and as easy to follow as possible so that it can also serve as a resource book for TBI or SCI patients or caregivers who want to better educate themselves about these conditions.

Traumatic brain injury (TBI) and traumatic spinal cord injury (SCI) cause the release of brain-specific proteins that may trigger an autoantibody response. These brain proteins are treated by the immune system as foreign antigens and can evoke the systemic production of both IgM and IgG isoforms. Increasing evidence shows that, in a subset of TBI patients, there are circulating autoantibodies recognizing a range of brain proteins. Autoantibodies against these are identified in SCI patients. Autoimmunity is triggered in TBI or SCI, targeting a range of brain-specific antigens in a subset of TBI patients. Such autoantibodies might be useful for biofluid-based diagnosis to identify patients who might benefit from immunotherapy. This chapter discusses how autoimmunity is triggered after TBI or SCI and summarizes identified brain antigens to which an autoimmune response has been observed as well as their clinical implications.

Casein zymography has become one of the gold standard assays for monitoring mammalian calcium-activated proteases (calpains) in purified enzyme, cell, or tissue samples. This calpain zymography method takes advantages of (1) casein is an excellent substrate for major isoforms of calpains (Calpain-1, 2 and 3), (2) the embedded casein is digested into small peptides where the calpain bands are located, thus creating a clear zone upon Commassie blue gel staining, and (3) the calpain isoforms have different gel mobility under native gel conditions. Casein zymography is also useful in studying reversibility of inhibitor binding to calpains.

In the USA, there are approximately 12,000 new cases of spinal cord injury (SCI) each year and some 1.2 million people living with paralysis due to SCI. Seven percent of them are paralyzed due to an accident or injury occurring while serving in the military. Here, we report a systematic study on protein biomarker candidates in a rat SCI model with either moderate or severe injury. Tissue, cerebrospinal fluid (CSF), and serum samples were obtained at 4 h, 24 h, and 7 days post-injury. The candidate biomarkers included axonal injury markers αII-spectrin breakdown products (SBDP150/145/120), neuronal cell body injury marker ubiquitin C-terminal hydrolase-L1 (UCH-L1), astrogliosis/astroglial injury markers S100 calcium-binding protein-β (S100β), glial fibrillary acidic protein (GFAP) and GFAP breakdown products (GBDPs), demyelination marker myelin basic protein (MBP), axonal injury marker phosphorylated neurofilament-H (pNF-H), and neuroinflammation marker interleukin-6 (IL-6). SBDP150/145, UCH-L1, GFAP, and S100β were found as acute biomarkers with significantly elevated levels within 24 h. GBDP44, GBDP38, and pNF-H are acute and subacute biomarkers that were found to have increased at 4 h, 24 h, and 7 days. MBP and SBDP120 were considered subacute biomarkers which were only detectable at 7 days post-injury. These results not only allow us to gain important insight into the patho-mechanisms of SCI but also showcase the possibility of using some of the protein biomarkers to track injury severity and disease progression and resolution. These biomarkers can potentially serve as tools that assist therapy development and clinical trials.

The neuroprotective effects of mesenchymal stem cells (MSCs) have been reported in rodent and in preliminary clinical studies. MSCs are usually transplanted to patients by systemic infusion. However, only a few of the infused MSCs are delivered to the brain because of pulmonary trapping and the blood-brain barrier. In this study, MSCs were topically applied to the site of traumatic brain injury (TBI) and the neuroprotective effects were assessed.TBI was induced in Sprague-Dawley (SD) rats with an electromagnetically controlled cortical impact device after craniotomy was performed between the bregma and lambda, 1 mm lateral to the midline. We applied 1.5 million MSCs, derived from the adipose tissue of transgenic green fluorescent protein (GFP)-SD rats, to the exposed cerebral cortex at the injured site. The MSCs were held in position by a thin layer of fibrin. Neurological function in the test (n = 10) and control (n = 10) animals was evaluated using the rotarod test, the water maze test, and gait analysis at different time points.Within 5 days following topical application, GFP-positive cells were found in the brain parenchyma. These cells co-expressed with markers of Glial fibrillary acidic protein (GFAP), nestin, and NeuN. There was less neuronal death in CA1 and CA3 of the hippocampus in the test animals. Neurological functional recovery was significantly improved.Topically applied MSCs can migrate to the injured brain parenchyma and offer neuroprotective effects.

A number of experimental models of blast brain injury have been implemented in rodents and larger animals. However, the variety of blast sources and the complexity of blast wave biophysics have made data on injury mechanisms and biomarkers difficult to analyze and compare. Recently, we showed the importance of rat position towards blasts generated by an external shock tube. In this study, we further characterized blasts producing moderate traumatic brain injury (TBI) and defined “composite” blast and primary blast exposure setups. Schlieren optics visualized interaction between the head and a shock wave generated by an external shock tube, revealing strong head acceleration upon positioning the rat on-axis with the shock tube (composite blast), but negligible skull movement upon peak over-pressure exposure off-axis (primary blast). Brain injury signatures of a primary blast hitting the frontal head were assessed and compared to damage produced by composite blast. Low to negligible levels of neurodegeneration were found following primary blast compared to composite blast by silver staining. However, persistent gliosis in the hippocampus and accumulation of GFAP/CNPase in the circulation was detected after both primary and composite blasts. In conclusion, neuro-glial biomarkers of brain injury were elevated at all blast setups. The most significant and persistent changes in neuronal markers were found after composite blast, while astrocyte and oligodendrocyte biomarkers GFAP and CNPase were up-regulated following both composite and primary blast exposure.

Biochemical markers are urgently needed to improve diagnosis, guide molecularly targeted therapy, and monitor activity and therapeutic response in traumatic brain injury. Proteomics methods based on mass spectrometry hold special promise for the discovery of novel biomarkers that might form the foundation for new clinical blood tests, but to date there are no biomarkers of brain injury approved by Food and Drug Administration (FDA). This chapter will provide a detailed outline of the overall process of biomarker discovery, the regulatory considerations necessary for a biomarker to file for approval by FDA, and information on their clinical utility for diagnosis, management, and prognosis of patients exposed to severe brain injuries.

Traumatic brain injury is a significant disease affecting 1.4 to 2 million patients every year in the USA. Currently, there are no FDA-approved therapeutic remedies to treat TBI despite the fact that there have been over 200 clinical drug trials, all which have failed. These drugs used the traditional single drug-to-target approach of drug discovery and development. An alternative based upon the advances in genomics, proteomics, bioinformatic tools, and systems biology software has enabled us to use a Systems Biology-based approach to drug discovery and development for TBI. It focuses on disease-relevant converging pathways as potential therapeutic intervention points and is accompanied by downstream biomarkers that allow for the tracking of drug targeting and appears to correlate with disease mitigation. When realized, one is able to envision that a companion diagnostic will be codeveloped along the therapeutic compound. This "theranostic" approach is perfectly positioned to align with the emerging trend toward "personalized medicine".

The use of methamphetamine (METH) as recreational drugs is a growing problem worldwide with recent concerns that it might cause long-lasting harmful effects to the human brain. METH is an illicit drug that is known to exert neurotoxic effects on both dopaminergic and serotonergic neural systems. Our laboratory has been studying the biochemical mechanisms underlying METH-induced neurotoxic effects both in vivo and in vitro. Our psychoproteomics METH abuse research focuses on the global alteration of cortical protein expression in rats treated with acute METH. In our analysis, an altered protein expression was identified using a multistep protein separation/proteomic platform. Differential changes of the selected proteins were further confirmed by quantitative immunoblotting. Our study identified 82 differentially expressed proteins, 40 of which were downregulated and 42 of which were upregulated post acute METH treatment. In this chapter, we describe the current protocols for the neuronal cell culture in vitro and the in vivo rat model of acute METH treatment (4 x 10 mg/kg) coupled with the description current bioinformatics analysis utilized to analyze the different implicated interaction protein/gene maps that reflected on the altered functions observed. These methods and protocols are discussed in the paradigm of the acute model of METH drug abuse and neuronal cell culture and can be applied on other models of substance abuse such as on MDMA or cocaine.

In recent years, the term proteomics is often mentioned together with biomarker discovery, as proteomic studies have the capability of identifying unique and unobvious protein biomarkers from tissues or biofluids derived from animal models or human clinical samples inflicted with various diseases. Proteomics has yielded hundreds of potential biomarker candidates. However, biomarker discovery is only the beginning of a long road for generating a validated, clinically relevant, and FDA-approved biomarker assay. Many technical, financial, legal, and regulatory hurdles have to be overcome before the components can be commercially produced (1, 2). This chapter outlines in a condensed version the steps to successfully develop clinically acceptable biomarkers, given the marker of choice withstands the rigor of developmental challenges along the road.

Like proteomics more generally, neuroproteomics has recently been linked to the discovery of biochemical markers of central nervous system (CNS) injury and disease. Although neuroproteomics has enjoyed considerable success in discovery of candidate biomarkers, there are a number of challenges facing investigators interested in developing clinically useful platforms to assess biomarkers for damage to the CNS. These challenges include intrinsic physiological complications such as the blood-brain barrier. Effective translation of biomarkers to clinical practice also requires development of entirely novel pathways and product development strategies. Drawing from lessons learned from applications of biomarkers to traumatic brain injury, this study outlines major elements of such a pathway. As with other indications, biomarkers can have three major areas of application: (1) drug development; (2) diagnosis and prognosis; (3) patient management. Translation of CNS biomarkers to practical clinical platforms raises a number of integrated elements. Biomarker discovery and initial selection needs to be integrated at the earliest stages with components that will allow systematic prioritization and triage of biomarker candidates. A number of important criteria need to be considered in selecting clinical biomarker candidates. Development of proof of concept assays and their optimization and validation represent an often overlooked feature of biomarker translational research. Initial assay optimization should confirm that assays can detect biomarkers in relevant clinical samples. Since access to human clinical samples is critical to identification of biomarkers relevant to injury and disease as well as for assay development, design of human clinical validation studies is an important component of translational biomarker research platforms. Although these clinical studies share much in common with clinical trials for assessment of drug therapeutic efficacy, there are a number of considerations unique to these efforts. Finally, platform selection and potential assay commercialization need to be considered. Decisions regarding whether or not to seek FDA approval also significantly influence translational research structures.

Calcium dyshomeostasis is involved in neuropathological conditions such as traumatic brain injury (TBI), stroke, and neurodegenerative diseases. Under such conditions in the brain, calmodulin (CaM), a Ca(2+) sensor, mediates critical signaling functions through binding and regulating a diverse population of downstream targets referred to as calmodulin-binding proteins (CaMBPs). We developed a CaM-affinity capture method followed by reversed-phase liquid chromatography tandem mass spectrometry (RPLC-MSMS) to study the calcium-dependent CaM-binding proteome in rat brain. A total of 69 potential CaMBPs were identified by this proteomic technique, of which 26 were known CaMBPs and 43 were putative novel CaMBPs. This study shows that the CaM-affinity capture when coupled with tandem mass spectrometry may serve as an effective tool toward constructing a brain CaM-binding proteomic network. The general methods described here can be applied to study possible alternations of calmodulin-binding proteome in neurological, neurodegenerative, and psychiatric disorders.

Methamphetamine (METH) is recognized as one of the most abused psychostimulants in the USA. METH is an illicit drug that is known to exert neurotoxic effects on both dopaminergic and serotonergic neural systems. Our laboratory has been studying the biochemical mechanisms underlying MDMA and METH-induced neurotoxic effects both in vivo and in vitro. Our substance abuse research focuses on the global alteration of cortical protein expression in rats treated with acute METH. Altered protein expression was identified using a multistep protein separation/proteomic platform. Differential changes of the selected proteins were further confirmed by quantitative immunoblotting. Our study identified 82 differentially expressed proteins, 40 of which were downregulated and 42 of which were upregulated post acute METH treatment. Proteins that were shown to be downregulated included collapsin response mediator protein-2 (CRMP-2), superoxide dismutase 1 (SOD 1), and phosphatidylethanolamine-binding protein-1 (PEBP-1). Proteins that were shown to be upregulated included authophagy-linked microtubule-associated protein light chain 3 (LC3), synapsin-1, and Parkinsonism-linked ubiquitin carboxy-terminal hydroxylase-L1 (UCH-L1). This differential protein expression highlights on the neurotoxic mechanism involved in METH exposure as well as to discover potential markers for METH-induced neurotoxicity. In this chapter, we describe the current protocols for the in vivo rat model of acute METH treatment (40 mg/kg) coupled with the description of the multistep separation platform applied. These methods and protocols are discussed in the paradigm of acute model of methamphetamine drug abuse and can be applied to other models of substance abuse such as to MDMA or cocaine.

Neuroproteomics entails wide-scope study of the nervous system proteome in both its content and dynamics. The field employs high-end analytical mass spectrometry and novel high-throughput antibody approaches to characterize as many proteins as possible. The most common application has been differential analysis to identify a limited set of highly dynamic proteins associated with injury, disease, or other altered states of the nervous system. Traumatic brain injury (TBI) is an important neurological condition where neuroproteomics has revolutionized the characterization of protein dynamics, leading to a greater understanding of post-injury biochemistry. Further, proteins of altered abundance or post-translational modifications identified by neuroproteomic studies are candidate biochemical markers of TBI. This chapter explores the use of neuroproteomics in the study of TBI and the validation of identified putative biomarkers for subsequent clinical translation into novel injury diagnostics.

PURPOSE OF REVIEW: The scarcity of pharmacological neuroprotective treatments for traumatic brain injury is a concern being targeted on various fronts. This review examines the latest treatments under investigation. RECENT FINDINGS: In the last 12-18 months, no drug has completed phase III clinical trials as a clearly proven method to treat traumatic brain injury. While the drugs work in rodents, when they make it to clinical trial they have failed primarily due to negative side-effects. Those still in trial show promise, and even those rejected have undergone modifications and now show potential, e.g. second-generation N-methyl-D-aspartic acid and alpha-amino-3-hydroxy-methyl-4-isoxazolyl-propionic acid receptor antagonists, calpain inhibitors, and cyclosporine A analogues. Also, several drugs not previously given much attention, such as the antibiotic minocycline, estrogen and progesterone, and a drug already approved for other diseases, erythropoietin, are being examined. Finally, a treatment generating some controversy, but showing potential, is the application of hypothermia to the patients. SUMMARY: Clearly, finding treatments for traumatic brain injury is not going to be easy and is evidently going to require numerous trials. The good news is that we are closer to finding one or more methods for treating traumatic brain injury patients.

Ecstasy use is a growing problem in the United States. Techniques to demonstrate and characterize the toxicity associated with its use have been limited and employed infrequently. In this study, we compare the deleterious effects of ecstasy use in rats with that of methamphetamine and traumatic brain injury. Specifically, we investigate the degradation of structural proteins alphaII-spectrin and tau by the pro-necrotic calpain and pro-apoptotic caspase systems. Ecstasy-induced neurotoxicity is shown after 24 hours, although to a much lesser extent than that of methamphetamine or traumatic brain injury. Neurotoxicity is still evident after 72 hours. Furthermore, apoptosis of the liver is seen 72 hours after ecstasy use. Use of protease inhibitors may be useful in preventing ecstasy-induced toxicity.

We provide the first data that cathepsin B (Cath B), a lysosomal cysteine protease, is up-regulated following contusion-spinal cord injury (SCI). Following T12 laminectomy and moderate contusion, Cath B mRNA and protein expression profiles were examined from 2 to 168 h post-injury in rats using real-time PCR and immunoblots, respectively. Contusion injury significantly increased [mRNA]Cath B in the injury site and adjacent segments over sham injury levels. While the largest [mRNA]Cath B induction (20-fold over naive) was seen in the injury site, the caudal segment routinely yielded [mRNA]Cath B levels greater than 10-fold over naive. Interestingly, sham injury animals also experienced mRNA induction at several time points at the injury site and in segments rostral and caudal to the injury site. Contusion injury also significantly elevated levels of Cath B proenzyme protein (37 kDa) over sham injury in the injury site (48, 72 and 168 h post-injury). Furthermore, significant protein increases of single and double chain Cath B (both active forms) occurred at the injury site at 72 and 168 h post-injury. Similar significant increases in Cath B protein levels were seen in areas adjacent to the injury site. The induction of Cath B mRNA and protein expression following contusion injury is previously undescribed and suggests that Cath B may potentially be involved in the secondary injury cascade, perhaps for as long as 1 week post-injury.