Neurodegeneration is a seminal feature of many neurological disorders. Chronic traumatic encephalopathy (CTE) is caused by repetitive head impacts (RHI) and is characterized by sulcal tau pathology. However, quantitative assessments of regional neurodegeneration in CTE have not been described.
View Article and Find Full Text PDFPostmortem human brain tissue is a critical resource for studying neurodegenerative disease, providing critical insights into cellular morphology, pathology, and network connectivity. To improve standard microscopy and enable high-resolution, three-dimensional (3D) images of tissues at the subcellular level, tissue-clearing methods have been developed. These 3D images allow for the analysis of large regions of interest and can be used to study structural and spatial changes that occur during neurodegeneration.
View Article and Find Full Text PDFChronic traumatic encephalopathy (CTE) is a neurodegenerative disease associated with exposure to repetitive head impacts (RHI) and characterized by perivascular accumulations of hyperphosphorylated tau protein (p-tau) at the depths of the cortical sulci. Studies of living athletes exposed to RHI, including concussive and nonconcussive impacts, have shown increased blood-brain barrier permeability, reduced cerebral blood flow, and alterations in vasoreactivity. Blood-brain barrier abnormalities have also been reported in individuals neuropathologically diagnosed with CTE.
View Article and Find Full Text PDFHippocampal sclerosis (HS) is associated with advanced age as well as transactive response DNA-binding protein with 43 kDa (TDP-43) deposits. Both hippocampal sclerosis and TDP-43 proteinopathy have also been described in chronic traumatic encephalopathy (CTE), a neurodegenerative disease linked to exposure to repetitive head impacts (RHI). However, the prevalence of HS in CTE, the pattern of TDP-43 pathology, and associations of HS and TDP-43 with RHI are unknown.
View Article and Find Full Text PDFChronic traumatic encephalopathy (CTE) is a neurodegenerative disease linked to repetitive head impacts (RHI) and characterized by perivascular hyperphosphorylated tau (p-tau) deposits. The role of vascular injury, blood-brain barrier leakage, and neuroinflammation in CTE pathogenesis is not well understood. We performed quantitative immunoassays for intercellular adhesion molecule 1 (ICAM1), vascular cellular adhesion molecule 1 (VCAM1), and C-reactive protein (CRP) within the postmortem dorsolateral frontal cortex of participants with and without a history of RHI and CTE (n = 156), and tested for associations with RHI, microgliosis, and tau pathology measures.
View Article and Find Full Text PDFRepetitive head impacts (RHI) and traumatic brain injuries are risk factors for the neurodegenerative diseases chronic traumatic encephalopathy (CTE) and amyotrophic lateral sclerosis (ALS). ALS and CTE are distinct disorders, yet in some instances, share pathology, affect similar brain regions, and occur together. The pathways involved and biomarkers for diagnosis of both diseases are largely unknown.
View Article and Find Full Text PDFProbable rapid eye movement (REM) sleep behavior disorder (pRBD) is a synucleinopathy-associated parasomnia in which loss of REM sleep muscle atonia results in motor behavior during REM sleep, including dream enactment. Traumatic brain injury is independently associated with increased risk of pRBD and Lewy body disease, and both pRBD and Lewy body disease are often observed in chronic traumatic encephalopathy (CTE). However, the frequency and pathological substrate of pRBD in CTE have not been formally studied and remain unknown.
View Article and Find Full Text PDFA large body of evidence indicates that dysregulation of cerebral biometals (Fe, Cu, Zn) and their interactions with amyloid precursor protein (APP) and Aβ amyloid may contribute to the Alzheimer's disease (AD) Aβ amyloid pathology. However, the molecular underpinnings associated with the interactions are still not fully understood. Herein we have further validated the exacerbation of Aβ oligomerization by Cu and HO in vitro.
View Article and Find Full Text PDFJ Neuropathol Exp Neurol
September 2018
Traumatic brain injury has been associated with increased risk of Parkinson disease and parkinsonism, and parkinsonism and Lewy body disease (LBD) can occur with chronic traumatic encephalopathy (CTE). To test whether contact sports and CTE are associated with LBD, we compared deceased contact sports athletes (n = 269) to cohorts from the community (n = 164) and the Boston University Alzheimer disease (AD) Center (n = 261). Participants with CTE and LBD were more likely to have β-amyloid deposition, dementia, and parkinsonism than CTE alone (p < 0.
View Article and Find Full Text PDFImportance: Players of American football may be at increased risk of long-term neurological conditions, particularly chronic traumatic encephalopathy (CTE).
Objective: To determine the neuropathological and clinical features of deceased football players with CTE.
Design, Setting, And Participants: Case series of 202 football players whose brains were donated for research.
Chronic traumatic encephalopathy (CTE) is a progressive neurodegenerative disorder linked to repetitive traumatic brain injury (TBI) and characterized by deposition of hyperphosphorylated tau at the depths of sulci. We sought to determine the presence of CTE pathology in a brain bank for neurodegenerative disorders for individuals with and without a history of contact sports participation. Available medical records of 1721 men were reviewed for evidence of past history of injury or participation in contact sports.
View Article and Find Full Text PDFChronic traumatic encephalopathy (CTE) is a neurodegenerative disease associated with repetitive mild traumatic brain injury. It is defined pathologically by the abnormal accumulation of tau in a unique pattern that is distinct from other tauopathies, including Alzheimer's disease (AD). Although trauma has been suggested to increase amyloid β peptide (Aβ) levels, the extent of Aβ deposition in CTE has not been thoroughly characterized.
View Article and Find Full Text PDFThe Wnt receptor Ryk is an evolutionary-conserved protein important during neuronal differentiation through several mechanisms, including γ-secretase cleavage and nuclear translocation of its intracellular domain (Ryk-ICD). Although the Wnt pathway may be neuroprotective, the role of Ryk in neurodegenerative disease remains unknown. We found that Ryk is up-regulated in neurons expressing mutant huntingtin (HTT) in several models of Huntington's disease (HD).
View Article and Find Full Text PDFCaspase-mediated cell death contributes to the pathogenesis of motor neuron degeneration in the mutant SOD1(G93A) transgenic mouse model of amyotrophic lateral sclerosis (ALS), along with other factors such as inflammation and oxidative damage. By screening a drug library, we found that melatonin, a pineal hormone, inhibited cytochrome c release in purified mitochondria and prevented cell death in cultured neurons. In this study, we evaluated whether melatonin would slow disease progression in SOD1(G93A) mice.
View Article and Find Full Text PDFChronic traumatic encephalopathy is a progressive tauopathy that occurs as a consequence of repetitive mild traumatic brain injury. We analysed post-mortem brains obtained from a cohort of 85 subjects with histories of repetitive mild traumatic brain injury and found evidence of chronic traumatic encephalopathy in 68 subjects: all males, ranging in age from 17 to 98 years (mean 59.5 years), including 64 athletes, 21 military veterans (86% of whom were also athletes) and one individual who engaged in self-injurious head banging behaviour.
View Article and Find Full Text PDFMelatonin mediates neuroprotection in several experimental models of neurodegeneration. It is not yet known, however, whether melatonin provides neuroprotection in genetic models of Huntington's disease (HD). We report that melatonin delays disease onset and mortality in a transgenic mouse model of HD.
View Article and Find Full Text PDFHuntington's disease (HD) is an autosomal dominant neurodegenerative disorder. Oxidative damage has been associated with pathological neuronal loss in HD. The therapeutic modulation of oxidative stress and mitochondrial function using low molecular weight compounds may be an important strategy for delaying the onset and slowing the progression of HD.
View Article and Find Full Text PDFAlthough a direct causative pathway from the gene mutation to the selective neostriatal neurodegeneration remains unclear in Huntington's disease (HD), one putative pathological mechanism reported to play a prominent role in the pathogenesis of this neurological disorder is mitochondrial dysfunction. We examined mitochondria in preferentially vulnerable striatal calbindin-positive neurons in moderate-to-severe grade HD patients, using antisera against mitochondrial markers of COX2, SOD2 and cytochrome c. Combined calbindin and mitochondrial marker immunofluorescence showed a significant and progressive grade-dependent reduction in the number of mitochondria in spiny striatal neurons, with marked alteration in size.
View Article and Find Full Text PDFAmyotroph Lateral Scler
December 2010
There is strong evidence from studies in humans and animal models to suggest the involvement of energy metabolism defects in neurodegenerative diseases. Uridine, a pyrimidine nucleoside, has been suggested to be neuroprotective in neurological disorders by improving bioenergetic effects, increasing ATP levels and enhancing glycolytic energy production. We assessed whether uridine treatment extended survival and improved the behavioral and neuropathological phenotype observed in G93A-ALS mice.
View Article and Find Full Text PDFHuntington's disease (HD) is a neurodegenerative disorder previously thought to be of primary neuronal origin, despite ubiquitous expression of mutant huntingtin (mHtt). We tested the hypothesis that mHtt expressed in astrocytes may contribute to the pathogenesis of HD. To better understand the contribution of astrocytes in HD in vivo, we developed a novel mouse model using lentiviral vectors that results in selective expression of mHtt into striatal astrocytes.
View Article and Find Full Text PDFPrior studies suggest that non-steroidal anti-inflammatory drugs (NSAIDs) may lower the incidence of Alzheimer's disease (AD) and delay onset or slow progression of symptoms in mouse models of AD. We examined the effects of chronic NSAID treatment in order to determine which elements of the pathological features might be ameliorated. We compared the effects of the NSAIDs ibuprofen and celecoxib on immunohistological and neurochemical markers at two different ages in APPxPS1 mice using measurements of amyloid plaque deposition, Abeta peptide levels, and neurochemical profiles using magnetic resonance spectroscopy (MRS).
View Article and Find Full Text PDFCoenzyme Q(10) (CoQ(10)) and creatine are promising agents for neuroprotection in neurodegenerative diseases via their effects on improving mitochondrial function and cellular bioenergetics and their properties as antioxidants. We examined whether a combination of CoQ(10) with creatine can exert additive neuroprotective effects in a MPTP mouse model of Parkinson's disease, a 3-NP rat model of Huntington's disease (HD) and the R6/2 transgenic mouse model of HD. The combination of the two agents produced additive neuroprotective effects against dopamine depletion in the striatum and loss of tyrosine hydroxylase neurons in the substantia nigra pars compacta (SNpc) following chronic subcutaneous administration of MPTP.
View Article and Find Full Text PDFRelease of mitochondrial cytochrome c resulting in downstream activation of cell death pathways has been suggested to play a role in neurologic diseases featuring cell death. However, the specific biologic importance of cytochrome c release has not been demonstrated in Huntington's disease (HD). To evaluate the role of cytochrome c release, we screened a drug library to identify new inhibitors of cytochrome c release from mitochondria.
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