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Advances in the development of imaging probes and aggregation inhibitors for alpha-synuclein.

Abnormal protein aggregation has been linked to many neurodegenerative diseases, including Parkinson's disease (PD). The main pathological hallmark of PD is the formation of Lewy bodies (LBs) and Lewy neurites, both of which contain the presynaptic protein alpha-synuclein (α-syn). Under normal conditions, native α-syn exists in a soluble unfolded state but undergoes misfolding and aggregation into toxic aggregates under pathological conditions. Toxic α-syn species, especially oligomers, can cause oxidative stress, membrane penetration, synaptic and mitochondrial dysfunction, as well as other d…

Neuropathology of autonomic dysfunction in synucleinopathies.

The synucleinopathies-Parkinson's disease, dementia with Lewy bodies, multiple system atrophy, and pure autonomic failure-result from distinct patterns of abnormal α-synuclein aggregation throughout the nervous system. Autonomic dysfunction in these disorders results from variable involvement of the central and peripheral autonomic networks. The major pathologic hallmark of Parkinson's disease and dementia with Lewy bodies is Lewy bodies and Lewy neurites; of multiple system atrophy, oligodendroglial cytoplasmic inclusions; and of pure autonomic failure, peripheral neuronal cytoplasmic inclusi…

IGF1 neuronal response in the absence of MECP2 is dependent on TRalpha 3.

Rett syndrome (RTT) is an X-linked neurodevelopmental disorder in which the MECP2 (methyl CpG-binding protein 2) gene is mutated. Recent stu … een IGF1/IGF1R and the TRalpha 3 and that over expression of IGF1R in RTT cells may be the cause of neurites improvement in neural RTT-derived neurons.

Solid-state NMR structure of a pathogenic fibril of full-length human α-synuclein.

Misfolded α-synuclein amyloid fibrils are the principal components of Lewy bodies and neurites, hallmarks of Parkinson's disease (PD). We present a high-resolution structure of an α-synuclein fibril, in a form that induces robust pathology in primary neuronal culture, determined by solid-state NMR spectroscopy and validated by EM and X-ray fiber diffraction. Over 200 unique long-range distance restraints define a consensus structure with common amyloid features including parallel, in-register β-sheets and hydrophobic-core residues, and with substantial complexity arising from diverse structura…

Environmental toxins trigger PD-like progression via increased alpha-synuclein release from enteric neurons in mice.

Pathological studies on Parkinson's disease (PD) patients suggest that PD pathology progresses from the enteric nervous system (ENS) and the … by enteric neurons and that released enteric alpha-synuclein is up-taken by presynaptic sympathetic neurites and retrogradely transported to the soma, where it accumulates. These results strongly suggest that pesticides can initiate the progression of PD pathology and that this progression is based on the transneuronal and retrograde axonal transport of al …

Synuclein activates microglia in a model of Parkinson's disease.

Parkinson's disease (PD) is the most common neurodegenerative movement disorder afflicting >500,000 patients in the United States alone. This age-related progressive disorder is typified by invariant loss of dopaminergic substantia nigra neurons (DAN), dystrophic neurites, the presence of alpha-synuclein (SYN) positive intracytoplasmic inclusions (Lewy bodies) in the remaining DAN, and activated microglia. As such, microglial activation and resultant increase in proinflammatory molecules have moved to the forefront of PD research as a potential pathobiologic mechanism of disease. Herein, we pr…

Erythropoietin promotes regeneration of adult CNS neurons via Jak2/Stat3 and PI3K/AKT pathway activation.

The cytokine hormone erythropoietin (EPO) has proved neuroprotective in CNS injury, and clinical trials for ischemic stroke are ongoing. The … ,000 IU rhEPO significantly increased numbers (2.66-fold) and length (8.31-fold) of newly generated neurites, without evoking rheological complications. EPO induced Stat3 phosphorylation in RGCs, and inhibition of Jak2/Stat3 abolished EPO-induced growth. EPO-facilitated neuritogenesis was paralleled by upregulation of Bcl-X(L), a Bcl-2 homologue capable of …

Role of protein-water interactions and electrostatics in alpha-synuclein fibril formation.

Deposition of misfolded alpha-synuclein is a critical factor in several neurodegenerative disorders. Filamentous alpha-synuclein is the major component of Lewy bodies and Lewy neurites, the intracellular inclusions in the dopaminergic neurons of the substantia nigra, which are considered the pathological hallmark of Parkinson's disease. We show here that anions induce partial folding of alpha-synuclein at neutral pH, forming a critical amyloidogenic intermediate, which leads to significant acceleration of the rate of fibrillation. The magnitude of the accelerating effect generally followed the…

BDNF is induced by wild-type alpha-synuclein but not by the two mutants, A30P or A53T, in glioma cell line.

Parkinson's disease (PD) is one of the most prevalent neurodegenerative diseases but its etiology is unclear. Alpha-synuclein (alpha-SN) is a major component of Lewy bodies and Lewy neurites, and its missense mutations, A30P and A53T, cause familial PD. In PD, alpha-SN-positive glial inclusions are distributed mainly in the dorso-medial region of the substantia nigra, which contains most of the surviving dopaminergic neurons, suggesting that alpha-SN expression might have a neuroprotective function in glial cells. To investigate this hypothesis, we established alpha-SN transfected C6 glioma ce…

Structural involvement of the glutamatergic presynaptic boutons in a transgenic mouse model expressing early onset amyloid pathology.

While the cholinergic depletion in Alzheimer's disease (AD) has been known for some time, a definitive involvement of other neurotransmitter … o have a statistically significant effect on the relative area occupied by dystrophic glutamatergic neurites in the peri-plaque neuropile. These findings support our hypothesis that the amyloid pathology progresses in a time and neurotransmitter specific manner, first in the cholinergic system which appears to be most vulnerable, followed by the glutamater …

Physiological and anatomical link between Parkinson-like disease and REM sleep behavior disorder.

Parkinson's disease (PD) is a progressive neurodegenerative disease that is caused by a loss of neurons in the ventral midbrain. Parkinsonia … d with Parkinsonism subsequently develop RBD. Postmortem examination reveals that Lewy bodies, Lewy neurites, and alpha-synuclein are found in brainstem nuclei in both Parkinsonism and RBD patients. In this article, we will discuss evidence that Parkinsonism and RBD are physiologically and anatomically linked, based on our animal experiments and other stud …

Amino acid determinants of alpha-synuclein aggregation: putting together pieces of the puzzle.

Parkinson's disease is the second most common neurodegenerative disease, and results from loss of dopaminergic neurons in the substantia nigra. The aggregation and fibrillation of alpha-synuclein in the form of intracellular proteinaceous aggregates (Lewy bodies and Lewy neurites) have been implicated as a causative factor in this disease, as well as in several other neurodegenerative disorders, including dementia with Lewy bodies, Lewy body variant of Alzheimer's disease, multiple system atrophy and Hallervorden-Spatz disease. Thus, the aggregated forms of alpha-synuclein play a crucial role …

Tenascin-Y is concentrated in adult nerve roots and has barrier properties in vitro.

Several molecules have been identified as potential sources of the barriers to glial cell mixing and sensory regeneration that exist at the … cause the rapid collapse of sensory growth cones cultured on fibronectin, and regenerating sensory neurites preferentially migrate on fibronectin and avoid tenascin-Y in microstripe assays. We conclude that the expression pattern of tenascin-Y and its properties in vitro are consistent with a role as an inhibitor of glial cell migration and sensory regene …

TAG-1-deficient mice have marked elevation of adenosine A1 receptors in the hippocampus.

TAG-1 is a neural recognition molecule in the immunoglobulin superfamily that is predominantly expressed in the developing brain. Several lines of evidence suggest that TAG-1 is involved in the outgrowth, guidance, and fasciculation of neurites. To directly assess the function of TAG-1 in vivo, we have generated mice with a deletion in the gene encoding TAG-1 using homologous recombination in embryonic stem cells. Gross morphological analysis of the cerebellum, the spinal cord, and the hippocampus appeared normal in TAG-1-deficient mice. However, TAG-1 (-/-) mice showed the upregulation of the…

Establishment and characterization of human immature teratoma cell line (TES-1).

A new human immature teratoma cell line, TES-1, was established from a surgical specimen from a 12-year old male with third ventricular immature teratoma. TES-1 shows polygonal morphology rich in neurites, and proliferated as adherent monolayer, with an approximate population doubling time of 48 hours. Electron microscopic analysis revealed the presence of swollen rough endoplasmic reticulum, and prominent lipid droplets, lysosomes and microfilaments. The chromosome numbers were between 41 and 160 (mode 78), including abnormal karyotypes 1p-, 5q-, 12p+ and 17p+ (G-band analysis). Hetero-transp…

Ubiquitin-related cytoskeletal abnormality in frontotemporal dementia: immunohistochemical and immunoelectron microscope studies.

Although reports of dementia lacking the distinctive non-Alzheimer-type histopathology have been increasing, the concept is still far from c … es. Recently, a new ubiquitin-related abnormality, characterized by ubiquitinated inclusions in the neurites, has been found in some FTD cases. Using immunoelectron microscopy with immunogold particles, we have found that in these two disease conditions ubiquitinated inclusions consist of abnormal filaments of 10-15 nm in diameter. Our results support the …

Abnormal distribution of neurofilament L in neurons with Alzheimer's disease.

Abnormality of cytoskeletal proteins is closely related to the pathology of Alzheimer's disease. As neurofilament proteins are major cytoskeletal components of neurons, abnormality of neurofilaments is proposed in brain with Alzheimer's disease. Free-floating sections of the hippocampus with Alzheimer's disease were studied immunohistochemically, using a polyclonal antibody specifically bound to the tail region of neurofilament L (NF-L). In brains with early onset type of Alzheimer's disease, many neurons and dystrophic neurites were labeled by the antibody, while these observations were not s…

Нейрональные и глиальные включения в различные неврологические заболевания имеют общие характеристики фосфорилации.

Аккумуляция тау в виде парных вертолётных ниток (PHF) в мозге болезни Альцгеймера считается аномальной фосфорилированной на отдельных участках. Для сравнения состояния фосфорилации тау-позитивных нейронных интеграций среди различных неврологических заболеваний мы провели обследование этих повреждений с помощью трех четко определенных PHF/tau моноклоналов, C5, M4 и tau 1, которые, скорее всего, распознают три участка фосфорилирования с пролинным курсом в PHF-tau. В мозге болезни Альцгеймера все три моноклана, сильно иммунизированные внутриклеточные нейрофибрилляторы, нейропильные нити, старинны

Совпадение в аннотации оригинала
Tau accumulating as paired helical filaments (PHF) in Alzheimer's disease brain is considered to be abnormally phosphorylated on distinct si … nals intensely immunostained intracellular neurofibrillary tangles, neuropil threads, senile plaque neurites, and "pretangle neurons" in a phosphorylation-dependent manner. They also stained, in the same manner, Pick bodies in Pick's disease, and neurofibrillary tangles and neuropil threads in various tangle-forming neurologic diseases. In most of these di …

Comparative ultrastructural neuropathology of naturally occurring bovine spongiform encephalopathy and experimentally induced scrapie and Creutzfeldt-Jakob disease.

We report the ultrastructural neuropathology of bovine spongiform encephalopathy (BSE), a recently described slow virus disease first recogn … s, such as mitochondria and dense bodies, which were entrapped within the filamentous masses. Other neurites accumulated electron-dense bodies, and still others electron-lucent cisterns and branching tubules. Membrane-bound neuronal inclusions, composed of tubules measuring 10 nm in diameter, were found in axonal terminals. Tubulovesicular structures were …

Immuno-electron-microscopic localization of complements in amyloid fibrils of senile plaques.

The presence of components of immunoglobulins (Ishii et al. 1975) and complements (Eikelenboom and Stam 1982) in senile plaques suggests tha … ively localized on the amyloid fibrils, but no other tissue elements, such as normal or degenerated neurites, neurofibrillary tangles, or glia. The results indicate the presence of immune complex in amyloid fibrils of senile plaques, and little association of complements in senile plaques with neurofilament protein.