Phosphorylation of the amyloid β-peptide at Ser26 stabilizes oligomeric assembly and increases neurotoxicity
Abstract Aggregation and toxicity of the amyloid β-peptide (Aβ) are considered as critical events in the initiation and progression of Alzheimer’s disease (AD). Recent evidence indicated that soluble oligomeric Aβ assemblies exert pronounced toxicity, rather than larger fibrillar aggregates that deposit in the forms of extracellular plaques. While some rare mutations in the Aβ sequence that cause early-onset AD promote the oligomerization, molecular mechanisms that induce the formation or stabilization of oligomers of the wild-type Aβ remain unclear. Here, we identified an Aβ va...
Source: Acta Neuropathologica - February 22, 2016 Category: Neurology Source Type: research

Monomethylated and unmethylated FUS exhibit increased binding to Transportin and distinguish FTLD-FUS from ALS- FUS
Abstract Deposition of the nuclear DNA/RNA-binding protein Fused in sarcoma (FUS) in cytosolic inclusions is a common hallmark of some cases of frontotemporal lobar degeneration (FTLD-FUS) and amyotrophic lateral sclerosis (ALS-FUS). Whether both diseases also share common pathological mechanisms is currently unclear. Based on our previous finding that FUS deposits are hypomethylated in FTLD-FUS but not in ALS-FUS, we have now investigated whether genetic or pharmacological inactivation of Protein arginine methyltransferase 1 (PRMT1) activity results in unmethylated FUS or in alternatively methylated forms of FUS....
Source: Acta Neuropathologica - February 19, 2016 Category: Neurology Source Type: research

The role of APOE in cerebrovascular dysfunction
Abstract The ε4 allele of the apolipoprotein E gene (APOE4) is associated with cognitive decline during aging, is the greatest genetic risk factor for Alzheimer’s disease and has links to other neurodegenerative conditions that affect cognition. Increasing evidence indicates that APOE genotypes differentially modulate the function of the cerebrovasculature (CV), with apoE and its receptors expressed by different cell types at the CV interface (astrocytes, pericytes, smooth muscle cells, brain endothelial cells). However, research on the role of apoE in CV dysfunction has not advanced as quickly as ot...
Source: Acta Neuropathologica - February 16, 2016 Category: Neurology Source Type: research

Resident microglia rather than peripheral macrophages promote vascularization in brain tumors and are source of alternative pro-angiogenic factors
Abstract Myeloid cells are an essential part of the glioblastoma microenvironment. However, in brain tumors the function of these immune cells is not sufficiently clarified. In our study, we investigated differential pro-angiogenic activities of resident microglia and peripheral macrophages and their impact on glioma vascularization and progression. Our data demonstrate stable accumulation of microglia/macrophages during tumor growth. These cells often interact with tumor blood vessels correlating with vascular remodeling. Here, we identified resident microglia as well as peripheral macrophages as part of the per...
Source: Acta Neuropathologica - February 14, 2016 Category: Neurology Source Type: research

Pathological α-synuclein distribution in subjects with coincident Alzheimer’s and Lewy body pathology
Abstract We investigated the distribution patterns of Lewy body-related pathology (LRP) and the effect of coincident Alzheimer disease (AD) pathology using a data-driven clustering approach that identified groups with different LRP pathology distributions without any diagnostic or researcher’s input in two cohorts including: Parkinson disease patients without (PD, n = 141) and with AD (PD-AD, n = 80), dementia with Lewy bodies subjects without AD (DLB, n = 13) and demented subjects with AD and LRP pathology (Dem-AD-LB, n = 308). The Dem-AD-LB group presented two LRP p...
Source: Acta Neuropathologica - February 14, 2016 Category: Neurology Source Type: research

Cell therapy centered on IL-1Ra is neuroprotective in experimental stroke
Abstract Cell-based therapies are emerging as new promising treatments in stroke. However, their functional mechanism and therapeutic potential during early infarct maturation has so far received little attention. Here, we asked if cell-based delivery of the interleukin-1 receptor antagonist (IL-1Ra), a known neuroprotectant in stroke, can promote neuroprotection, by modulating the detrimental inflammatory response in the tissue at risk. We show by the use of IL-1Ra-overexpressing and IL-1Ra-deficient mice that IL-1Ra is neuroprotective in stroke. Characterization of the cellular and spatiotemporal production of ...
Source: Acta Neuropathologica - February 9, 2016 Category: Neurology Source Type: research

Methylation-based classification of benign and malignant peripheral nerve sheath tumors
Abstract The vast majority of peripheral nerve sheath tumors derive from the Schwann cell lineage and comprise diverse histological entities ranging from benign schwannomas and neurofibromas to high-grade malignant peripheral nerve sheath tumors (MPNST), each with several variants. There is increasing evidence for methylation profiling being able to delineate biologically relevant tumor groups even within the same cellular lineage. Therefore, we used DNA methylation arrays for methylome- and chromosomal profile-based characterization of 171 peripheral nerve sheath tumors. We analyzed 28 conventional high-grade...
Source: Acta Neuropathologica - February 8, 2016 Category: Neurology Source Type: research

Proaggregant nuclear factor(s) trigger rapid formation of α-synuclein aggregates in apoptotic neurons
In this study we demonstrate that filamentous αS aggregates form in neurons in response to apoptosis induced by staurosporine or other toxins-6-hydroxy-dopamine and 1-methyl-4-phenylpyridinium (MPP+). Interaction between αS and proaggregant nuclear factor(s) is associated with disruption of nuclear envelope integrity. Knocking down a key nuclear envelop constituent protein, lamin B1, enhances αS aggregation. Moreover, in vitro and in vivo experimental models demonstrate that aggregates released upon cell breakdown can be taken up by surrounding cells. Accordingly, we suggest that at least some αS ag...
Source: Acta Neuropathologica - February 2, 2016 Category: Neurology Source Type: research

Human spinal autografts of olfactory epithelial stem cells recapitulate donor site histology, maintaining proliferative and differentiation capacity many years after transplantation
(Source: Acta Neuropathologica)
Source: Acta Neuropathologica - February 2, 2016 Category: Neurology Source Type: research

Axonal transport and secretion of fibrillar forms of α-synuclein, Aβ42 peptide and HTTExon 1
Abstract Accruing evidence suggests that prion-like behavior of fibrillar forms of α-synuclein, β-amyloid peptide and mutant huntingtin are responsible for the spread of the lesions that characterize Parkinson disease, Alzheimer disease and Huntington disease, respectively. It is unknown whether these distinct protein assemblies are transported within and between neurons by similar or distinct mechanisms. It is also unclear if neuronal death or injury is required for neuron-to-neuron transfer. To address these questions, we used mouse primary cortical neurons grown in microfluidic devices to measure the...
Source: Acta Neuropathologica - January 28, 2016 Category: Neurology Source Type: research

Updated TDP-43 in Alzheimer’s disease staging scheme
In this study, we update the TDP-43 in Alzheimer’s disease staging scheme by assessing the topography of TDP-43 in 193 cases of Alzheimer’s disease, in 14 different brain regions (eight previously described plus six newly reported) and use conditional probability to model the spread of TDP-43 across the 14 brain regions. We show that in addition to the eight original regions we previously reported [amygdala, entorhinal cortex, subiculum, dentate gyrus of the hippocampus, occipitotemporal cortex, inferior temporal cortex, middle frontal cortex and basal ganglia (putamen/globus pallidum)] that TDP-43 is also depo...
Source: Acta Neuropathologica - January 25, 2016 Category: Neurology Source Type: research

Genetic alterations in uncommon low-grade neuroepithelial tumors: BRAF , FGFR1 , and MYB mutations occur at high frequency and align with morphology
In this study, we have used massively parallel sequencing and various targeted molecular genetic approaches to study alterations in 91 LGNTs, mostly from children but including young adult patients. These tumors comprise dysembryoplastic neuroepithelial tumors (DNETs; n = 22), diffuse oligodendroglial tumors (d-OTs; n = 20), diffuse astrocytomas (DAs; n = 17), angiocentric gliomas (n = 15), and gangliogliomas (n = 17). Most LGNTs (84 %) analyzed by whole-genome sequencing (WGS) were characterized by a single driver genetic alteration. Alterations of FGFR1 occurred freq...
Source: Acta Neuropathologica - January 25, 2016 Category: Neurology Source Type: research

Genomic characterization of primary central nervous system lymphoma
Abstract Primary central nervous system lymphoma (PCNSL) is a rare malignancy confined to the central nervous system (CNS), and majority of PCNSL is pathologically classified as diffuse large B-cell lymphoma (DLBCL). We have now performed whole-exome sequencing for 41 tumor tissues of DLBCL-type PCNSL and paired normal specimens and also RNA-sequencing for 30 tumors, revealing a very high frequency of nonsynonymous somatic mutations in PIM1 (100 %), BTG2 (92.7 %), and MYD88 (85.4 %). Many genes in the NF-κB pathway are concurrently mutated within the same tumors. Further, focal deletion or som...
Source: Acta Neuropathologica - January 12, 2016 Category: Neurology Source Type: research

Cerebrospinal fluid soluble TREM2 is higher in Alzheimer disease and associated with mutation status
Abstract Low frequency coding variants in TREM2 are associated with increased Alzheimer disease (AD) risk, while loss of functions mutations in the gene lead to an autosomal recessive early-onset dementia, named Nasu-Hakola disease (NHD). TREM2 can be detected as a soluble protein in cerebrospinal fluid (CSF) and plasma, and its CSF levels are elevated in inflammatory CNS diseases. We measured soluble TREM2 (sTREM2) in the CSF of a large AD case–control dataset (n = 180) and 40 TREM2 risk variant carriers to determine whether CSF sTREM2 levels are associated with AD status or mutation status. We al...
Source: Acta Neuropathologica - January 11, 2016 Category: Neurology Source Type: research

Re-emergence of neuroinfectiology
(Source: Acta Neuropathologica)
Source: Acta Neuropathologica - January 11, 2016 Category: Neurology Source Type: research

Serotonin 2B receptor slows disease progression and prevents degeneration of spinal cord mononuclear phagocytes in amyotrophic lateral sclerosis
Abstract Microglia are the resident mononuclear phagocytes of the central nervous system and have been implicated in the pathogenesis of neurodegenerative diseases such as amyotrophic lateral sclerosis (ALS). During neurodegeneration, microglial activation is accompanied by infiltration of circulating monocytes, leading to production of multiple inflammatory mediators in the spinal cord. Degenerative alterations in mononuclear phagocytes are commonly observed during neurodegenerative diseases, yet little is known concerning the mechanisms leading to their degeneration, or the consequences on disease progression. H...
Source: Acta Neuropathologica - January 7, 2016 Category: Neurology Source Type: research

Gliomatosis cerebri in children shares molecular characteristics with other pediatric gliomas
Abstract Gliomatosis cerebri (GC), a rare and deadly CNS neoplasm characterized by involvement of at least three cerebral lobes, predominantly affects adults. While a few small series have reported its occurrence in children, little is known about the molecular characteristics of pediatric GC. We reviewed clinical, radiological, and histological features of pediatric patients with primary GC treated at our institution over 15 years. Targeted sequencing of mutational hotspots in H3F3A, IDH1/2, and BRAF, and genome-wide analysis of DNA methylation and copy number abnormalities was performed in available tumors....
Source: Acta Neuropathologica - January 7, 2016 Category: Neurology Source Type: research

Mitochondria-associated membranes as hubs for neurodegeneration
Abstract There is a growing appreciation that membrane-bound organelles in eukaryotic cells communicate directly with one another through direct membrane contact sites. Mitochondria-associated membranes are specialized subdomains of the endoplasmic reticulum that function as membrane contact sites between the endoplasmic reticulum and mitochondria. These sites have emerged as major players in lipid metabolism and calcium signaling. More recently also autophagy and mitochondrial dynamics have been found to be regulated at ER-mitochondria contact sites. Neurons critically depend on mitochondria-associated membranes ...
Source: Acta Neuropathologica - January 7, 2016 Category: Neurology Source Type: research

Host–pathogen interactions in bacterial meningitis
Abstract Bacterial meningitis is a devastating disease occurring worldwide with up to half of the survivors left with permanent neurological sequelae. Due to intrinsic properties of the meningeal pathogens and the host responses they induce, infection can cause relatively specific lesions and clinical syndromes that result from interference with the function of the affected nervous system tissue. Pathogenesis is based on complex host–pathogen interactions, some of which are specific for certain bacteria, whereas others are shared among different pathogens. In this review, we summarize the recent progress mad...
Source: Acta Neuropathologica - January 7, 2016 Category: Neurology Source Type: research

Erratum to: Gliomatosis cerebri: no evidence for a separate brain tumor entity
(Source: Acta Neuropathologica)
Source: Acta Neuropathologica - January 7, 2016 Category: Neurology Source Type: research

Heterotypic seeding of Tau fibrillization by pre-aggregated Abeta provides potent seeds for prion-like seeding and propagation of Tau-pathology in vivo
Abstract Genetic, clinical, histopathological and biomarker data strongly support Beta-amyloid (Aβ) induced spreading of Tau-pathology beyond entorhinal cortex (EC), as a crucial process in conversion from preclinical cognitively normal to Alzheimer‘s Disease (AD), while the underlying mechanism remains unclear. In vivo preclinical models have reproducibly recapitulated Aβ-induced Tau-pathology. Tau pathology was thereby also induced by aggregated Aβ, in functionally connected brain areas, reminiscent of a prion-like seeding process. In this work we demonstrate, that pre-aggregated Aβ can...
Source: Acta Neuropathologica - January 6, 2016 Category: Neurology Source Type: research

Pur-alpha regulates cytoplasmic stress granule dynamics and ameliorates FUS toxicity
Abstract Amyotrophic lateral sclerosis is characterized by progressive loss of motor neurons in the brain and spinal cord. Mutations in several genes, including FUS, TDP43, Matrin 3, hnRNPA2 and other RNA-binding proteins, have been linked to ALS pathology. Recently, Pur-alpha, a DNA/RNA-binding protein was found to bind to C9orf72 repeat expansions and could possibly play a role in the pathogenesis of ALS. When overexpressed, Pur-alpha mitigates toxicities associated with Fragile X tumor ataxia syndrome (FXTAS) and C9orf72 repeat expansion diseases in Drosophila and mammalian cell culture models. However, the fun...
Source: Acta Neuropathologica - January 4, 2016 Category: Neurology Source Type: research

Neuroinflammation impairs adaptive structural plasticity of dendritic spines in a preclinical model of Alzheimer’s disease
Abstract To successfully treat Alzheimer’s disease (AD), pathophysiological events in preclinical stages need to be identified. Preclinical AD refers to the stages that exhibit amyloid deposition in the brain but have normal cognitive function, which are replicated in young adult APPswe/PS1deltaE9 (deltaE9) mice. By long-term in vivo two-photon microscopy, we demonstrate impaired adaptive spine plasticity in these transgenic mice illustrated by their failure to increase dendritic spine density and form novel neural connections when housed in enriched environment (EE). Decrease of amyloid plaques by reducing ...
Source: Acta Neuropathologica - January 2, 2016 Category: Neurology Source Type: research

Propagation of Aβ, tau and α-synuclein pathology between experimental models and human reality: prions, propagons and propaganda
(Source: Acta Neuropathologica)
Source: Acta Neuropathologica - January 1, 2016 Category: Neurology Source Type: research

Cerebrovascular disease in ageing and Alzheimer’s disease
Abstract Cerebrovascular disease (CVD) and Alzheimer’s disease (AD) have more in common than their association with ageing. They share risk factors and overlap neuropathologically. Most patients with AD have Aβ amyloid angiopathy and degenerative changes affecting capillaries, and many have ischaemic parenchymal abnormalities. Structural vascular disease contributes to the ischaemic abnormalities in some patients with AD. However, the stereotyped progression of hypoperfusion in this disease, affecting first the precuneus and cingulate gyrus, then the frontal and temporal cortex and lastly the occipital ...
Source: Acta Neuropathologica - December 28, 2015 Category: Neurology Source Type: research

Microglia–blood vessel interactions: a double-edged sword in brain pathologies
Abstract Microglia are long-living resident immune cells of the brain, which secure a stable chemical and physical microenvironment necessary for the proper functioning of the central nervous system (CNS). These highly dynamic cells continuously scan their environment for pathogens and possess the ability to react to damage-induced signals in order to protect the brain. Microglia, together with endothelial cells (ECs), pericytes and astrocytes, form the functional blood–brain barrier (BBB), a specialized endothelial structure that selectively separates the sensitive brain parenchyma from blood circulation. M...
Source: Acta Neuropathologica - December 28, 2015 Category: Neurology Source Type: research

Immunotherapies in Alzheimer’s disease: Too much, too little, too late or off-target?
Abstract Years of research have highlighted the importance of the immune system in Alzheimer’s disease (AD), a system that, if manipulated during strategic time windows, could potentially be tackled to treat this disorder. However, to minimize adverse effects, it is essential to first grasp which exact aspect of it may be targeted. Several clues have been collected over the years regarding specific immune players strongly modulated during different stages of AD progression. However, the inherent complexity of the immune system as well as conflicting data make it quite challenging to pinpoint a specific immun...
Source: Acta Neuropathologica - December 21, 2015 Category: Neurology Source Type: research

Presymptomatic activation of the PDGF-CC pathway accelerates onset of ALS neurodegeneration
Abstract Amyotrophic lateral sclerosis (ALS) is a fatal neurodegenerative disease with unknown origins. Neurodegeneration in ALS mouse models occurs together with signs of disrupted blood–spinal cord barrier (BSCB) and regressed capillary network, but the molecular pathways contributing to these vascular pathologies remain unknown. We show that motor neurons of human sporadic ALS patients (n = 12) have increased gene expression of PDGFC and its activator PLAT and presymptomatic activation of the PDGF-CC pathway in SOD1 G93A mice leads to BSCB dysfunction. Decrea...
Source: Acta Neuropathologica - December 19, 2015 Category: Neurology Source Type: research

Antibody-mediated neutralization of myelin-associated EphrinB3 accelerates CNS remyelination
Abstract Remyelination in multiple sclerosis (MS) lesions often remains incomplete despite the presence of oligodendrocyte progenitor cells (OPCs). Amongst other factors, successful remyelination depends on the phagocytic clearance of myelin debris. However, the proteins in myelin debris that act as potent and selective inhibitors on OPC differentiation and inhibit CNS remyelination remain unknown. Here, we identify the transmembrane signalling protein EphrinB3 as important mediator of this inhibition, using a protein analytical approach in combination with a primary rodent OPC assay. In the presence of EphrinB3, ...
Source: Acta Neuropathologica - December 19, 2015 Category: Neurology Source Type: research

Astrocytes: a central element in neurological diseases
Abstract The neurone-centred view of the past disregarded or downplayed the role of astroglia as a primary component in the pathogenesis of neurological diseases. As this concept is changing, so is also the perceived role of astrocytes in the healthy and diseased brain and spinal cord. We have started to unravel the different signalling mechanisms that trigger specific molecular, morphological and functional changes in reactive astrocytes that are critical for repairing tissue and maintaining function in CNS pathologies, such as neurotrauma, stroke, or neurodegenerative diseases. An increasing body of evidence sho...
Source: Acta Neuropathologica - December 15, 2015 Category: Neurology Source Type: research

Next-generation sequencing in routine brain tumor diagnostics enables an integrated diagnosis and identifies actionable targets
In conclusion, we present the settings for high-throughput, adaptive next-generation sequencing in routine neuropathology diagnostics. Such an approach will likely become highly valuable in the near future for treatment decision making, as more therapeutic targets emerge and genetic information enters the classification of brain tumors. (Source: Acta Neuropathologica)
Source: Acta Neuropathologica - December 15, 2015 Category: Neurology Source Type: research

The first NINDS/NIBIB consensus meeting to define neuropathological criteria for the diagnosis of chronic traumatic encephalopathy
This study provides the first step towards the development of validated neuropathological criteria for CTE and will pave the way towards future clinical and mechanistic studies. (Source: Acta Neuropathologica)
Source: Acta Neuropathologica - December 14, 2015 Category: Neurology Source Type: research

Neurotropic virus infections as the cause of immediate and delayed neuropathology
Abstract A wide range of viruses from different virus families in different geographical areas, may cause immediate or delayed neuropathological changes and neurological manifestations in humans and animals. Infection by neurotropic viruses as well as the resulting immune response can irreversibly disrupt the complex structural and functional architecture of the central nervous system, frequently leaving the patient or affected animal with a poor or fatal prognosis. Mechanisms that govern neuropathogenesis and immunopathogenesis of viral infections are highlighted, using examples of well-studied virus infections t...
Source: Acta Neuropathologica - December 10, 2015 Category: Neurology Source Type: research

Aging-related tau astrogliopathy (ARTAG): harmonized evaluation strategy
Abstract Pathological accumulation of abnormally phosphorylated tau protein in astrocytes is a frequent, but poorly characterized feature of the aging brain. Its etiology is uncertain, but its presence is sufficiently ubiquitous to merit further characterization and classification, which may stimulate clinicopathological studies and research into its pathobiology. This paper aims to harmonize evaluation and nomenclature of aging-related tau astrogliopathy (ARTAG), a term that refers to a morphological spectrum of astroglial pathology detected by tau immunohistochemistry, especially with phosphorylation-dependent a...
Source: Acta Neuropathologica - December 10, 2015 Category: Neurology Source Type: research

Neuronal ceroid lipofuscinosis with DNAJC5/CSPα mutation has PPT1 pathology and exhibit aberrant protein palmitoylation
Abstract Neuronal ceroid lipofuscinoses (NCL) are a group of inherited neurodegenerative disorders with lysosomal pathology (CLN1-14). Recently, mutations in the DNAJC5/CLN4 gene, which encodes the presynaptic co-chaperone CSPα were shown to cause autosomal-dominant NCL. Although 14 NCL genes have been identified, it is unknown if they act in common disease pathways. Here we show that two disease-associated proteins, CSPα and the depalmitoylating enzyme palmitoyl-protein thioesterase 1 (PPT1/CLN1) are biochemically linked. We find that in DNAJC5/CLN4 patient brains, PPT1 is massively increased and mis-...
Source: Acta Neuropathologica - December 10, 2015 Category: Neurology Source Type: research

Prion-like propagation of mutant SOD1 misfolding and motor neuron disease spread along neuroanatomical pathways
Abstract A hallmark feature of amyotrophic lateral sclerosis (ALS) is that symptoms appear to spread along neuroanatomical pathways to engulf the motor nervous system, suggesting a propagative toxic entity could be involved in disease pathogenesis. Evidence for such a propagative entity emerged recently in studies using mice that express G85R-SOD1 mutant protein fused to YFP (G85R-SOD1:YFP). Heterozygous G85R-SOD1:YFP transgenic mice do not develop ALS symptoms out to 20 months of age. However, when newborns are injected with spinal homogenates from paralyzed mutant SOD1 mice, the G85R-SOD1:YFP mice develop p...
Source: Acta Neuropathologica - December 9, 2015 Category: Neurology Source Type: research

Prion-mediated neurodegeneration is associated with early impairment of the ubiquitin–proteasome system
Abstract Prion diseases are a group of fatal neurodegenerative disorders characterised by the accumulation of misfolded prion protein (PrPSc) in the brain. The critical relationship between aberrant protein misfolding and neurotoxicity currently remains unclear. The accumulation of aggregation-prone proteins has been linked to impairment of the ubiquitin–proteasome system (UPS) in a variety of neurodegenerative disorders, including Alzheimer’s, Parkinson’s and Huntington’s diseases. As the principal route for protein degradation in mammalian cells, this could have profound detrimental effec...
Source: Acta Neuropathologica - December 8, 2015 Category: Neurology Source Type: research

Aberrant association of misfolded SOD1 with Na + /K + ATPase-α3 impairs its activity and contributes to motor neuron vulnerability in ALS
Abstract Amyotrophic lateral sclerosis (ALS) is an adult onset progressive motor neuron disease with no cure. Transgenic mice overexpressing familial ALS associated human mutant SOD1 are a commonly used model for examining disease mechanisms. Presently, it is well accepted that alterations in motor neuron excitability and spinal circuits are pathological hallmarks of ALS, but the underlying molecular mechanisms remain unresolved. Here, we sought to understand whether the expression of mutant SOD1 protein could contribute to altering processes governing motor neuron excitability. We used the conformation specific a...
Source: Acta Neuropathologica - November 30, 2015 Category: Neurology Source Type: research

SNTF immunostaining reveals previously undetected axonal pathology in traumatic brain injury
Abstract Diffuse axonal injury (DAI) is a common feature of severe traumatic brain injury (TBI) and may also be a predominant pathology in mild TBI or “concussion”. The rapid deformation of white matter at the instant of trauma can lead to mechanical failure and calcium-dependent proteolysis of the axonal cytoskeleton in association with axonal transport interruption. Recently, a proteolytic fragment of alpha-II spectrin, “SNTF”, was detected in serum acutely following mild TBI in patients and was prognostic for poor clinical outcome. However, direct evidence that this fragment is a marker ...
Source: Acta Neuropathologica - November 20, 2015 Category: Neurology Source Type: research

Age-dependent defects of alpha-synuclein oligomer uptake in microglia and monocytes
Abstract Extracellular alpha-synuclein (αsyn) oligomers, associated to exosomes or free, play an important role in the pathogenesis of Parkinson’s disease (PD). Increasing evidence suggests that these extracellular moieties activate microglia leading to enhanced neuronal damage. Despite extensive efforts on studying neuroinflammation in PD, little is known about the impact of age on microglial activation and phagocytosis, especially of extracellular αsyn oligomers. Here, we show that microglia isolated from adult mice, in contrast to microglia from young mice, display phagocytosis deficits of fre...
Source: Acta Neuropathologica - November 17, 2015 Category: Neurology Source Type: research

Propagation of tau pathology: hypotheses, discoveries, and yet unresolved questions from experimental and human brain studies
Abstract Tau is a microtubule-associated protein and a key regulator of microtubule stabilization as well as the main component of neurofibrillary tangles—a principle neuropathological hallmark of Alzheimer’s disease (AD)—as well as pleomorphic neuronal and glial inclusions in neurodegenerative tauopathies. Cross-sectional studies of neurofibrillary pathology in AD reveal a stereotypic spatiotemporal pattern of neuronal vulnerability that correlates with disease severity; however, the relationship of this pattern to disease progression is less certain and exceptions to the typical pattern have be...
Source: Acta Neuropathologica - November 17, 2015 Category: Neurology Source Type: research

Non-prion-type transmission in A53T α-synuclein transgenic mice: a normal component of spinal homogenates from naïve non-transgenic mice induces robust α-synuclein pathology
(Source: Acta Neuropathologica)
Source: Acta Neuropathologica - November 5, 2015 Category: Neurology Source Type: research

Biochemical classification of tauopathies by immunoblot, protein sequence and mass spectrometric analyses of sarkosyl-insoluble and trypsin-resistant tau
Abstract Intracellular filamentous tau pathology is the defining feature of tauopathies, which form a subset of neurodegenerative diseases. We have analyzed pathological tau in Alzheimer’s disease, and in frontotemporal lobar degeneration associated with tauopathy to include cases with Pick bodies, corticobasal degeneration, progressive supranuclear palsy, and ones due to intronic mutations in MAPT. We found that the C-terminal band pattern of the pathological tau species is distinct for each disease. Immunoblot analysis of trypsin-resistant tau indicated that the different band patterns of the 7–18&nb...
Source: Acta Neuropathologica - November 4, 2015 Category: Neurology Source Type: research

Viral gene transfer of APPsα rescues synaptic failure in an Alzheimer’s disease mouse model
Abstract Alzheimer’s disease (AD) is characterized by synaptic failure, dendritic and axonal atrophy, neuronal death and progressive loss of cognitive functions. It is commonly assumed that these deficits arise due to β-amyloid accumulation and plaque deposition. However, increasing evidence indicates that loss of physiological APP functions mediated predominantly by neurotrophic APPsα produced in the non-amyloidogenic α-secretase pathway may contribute to AD pathogenesis. Upregulation of APPsα production via induction of α-secretase might, however, be problematic as this may als...
Source: Acta Neuropathologica - November 4, 2015 Category: Neurology Source Type: research

Highly encephalitogenic aquaporin 4-specific T cells and NMO-IgG jointly orchestrate lesion location and tissue damage in the CNS
Abstract In neuromyelitis optica (NMO), astrocytes become targets for pathogenic aquaporin 4 (AQP4)-specific antibodies which gain access to the central nervous system (CNS) in the course of inflammatory processes. Since these antibodies belong to a T cell-dependent subgroup of immunoglobulins, and since NMO lesions contain activated CD4+ T cells, the question arose whether AQP4-specific T cells might not only provide T cell help for antibody production, but also play an important role in the induction of NMO lesions. We show here that highly pathogenic, AQP4-peptide-specific T cells exist in Lewis rats, which rec...
Source: Acta Neuropathologica - November 3, 2015 Category: Neurology Source Type: research

Tracking CNS and systemic sources of oxidative stress during the course of chronic neuroinflammation
Abstract The functional dynamics and cellular sources of oxidative stress are central to understanding MS pathogenesis but remain elusive, due to the lack of appropriate detection methods. Here we employ NAD(P)H fluorescence lifetime imaging to detect functional NADPH oxidases (NOX enzymes) in vivo to identify inflammatory monocytes, activated microglia, and astrocytes expressing NOX1 as major cellular sources of oxidative stress in the central nervous system of mice affected by experimental autoimmune encephalomyelitis (EAE). This directly affects neuronal function in vivo, indicated by sustained elevated neurona...
Source: Acta Neuropathologica - October 31, 2015 Category: Neurology Source Type: research

Chronic traumatic encephalopathy pathology in a neurodegenerative disorders brain bank
In conclusion, this study has identified a small, yet significant, subset of individuals with neurodegenerative disorders and concomitant CTE pathology. CTE pathology was only detected in individuals with documented participation in contact sports. Exposure to contact sports was the greatest risk factor for CTE pathology. Future studies addressing clinical correlates of CTE pathology are needed. (Source: Acta Neuropathologica)
Source: Acta Neuropathologica - October 30, 2015 Category: Neurology Source Type: research

Antibodies produced by clonally expanded plasma cells in multiple sclerosis cerebrospinal fluid cause demyelination of spinal cord explants
We examined the binding of IgG1 monoclonal recombinant antibodies (rAbs) derived from MS patient CSF expanded B cell clones to central nervous system (CNS) tissue. MS rAbs displaying CNS binding to mouse and human CNS tissue were further tested for their ability to induce complement-mediated tissue injury in ex vivo spinal cord explant cultures. The staining of CNS tissue, primary human astrocytes and human neurons revealed a measurable bias in MS rAb binding to antigens preferentially expressed on astrocytes and neurons. MS rAbs that recognize myelin-enriched antigens were rarely detected. Both myelin-specific and some as...
Source: Acta Neuropathologica - October 28, 2015 Category: Neurology Source Type: research

RCAN1 overexpression promotes age-dependent mitochondrial dysregulation related to neurodegeneration in Alzheimer’s disease
Abstract Aging is the largest risk factor for Alzheimer’s disease (AD). Patients with Down syndrome (DS) develop symptoms consistent with early-onset AD, suggesting that overexpression of chromosome 21 genes such as Regulator of Calcineurin 1 (RCAN1) plays a role in AD pathogenesis. RCAN1 levels are increased in the brain of DS and AD patients but also in the human brain with normal aging. RCAN1 has been implicated in several neuronal functions, but whether its increased expression is correlative or causal in the aging-related progression of AD remains elusive. We show that brain-specific overexpression of t...
Source: Acta Neuropathologica - October 24, 2015 Category: Neurology Source Type: research

Histological evidence of chronic traumatic encephalopathy in a large series of neurodegenerative diseases
(Source: Acta Neuropathologica)
Source: Acta Neuropathologica - October 24, 2015 Category: Neurology Source Type: research