Search results for "YLOID"
showing 10 items of 526 documents
A disintegrin-metalloproteinase prevents amyloid plaque formation and hippocampal defects in an Alzheimer disease mouse model
2004
Alzheimer disease (AD) is characterized by excessive deposition of amyloid beta-peptides (A beta peptides) in the brain. In the nonamyloidogenic pathway, the amyloid precursor protein (APP) is cleaved by the alpha-secretase within the A beta peptide sequence. Proteinases of the ADAM family (adisintegrin and metalloproteinase) are the main candidates as physiologically relevant alpha-secretases, but early lethality of knockout animals prevented a detailed analysis in neuronal cells. To overcome this restriction, we have generated transgenic mice that overexpress either ADAM10 or a catalytically inactive ADAM10 mutant. In this report we show that a moderate neuronal overexpression of ADAM10 i…
Over-expression of two different forms of the α-secretase ADAM10 affects learning and memory in mice
2006
Members of the ADAM family (adisintegrin and metalloprotease) are the main candidates for physiologically relevant alpha-secretases. The alpha-secretase cleaves in the non-amyloidogenic pathway the amyloid precursor protein within the region of the Abeta peptides preventing their aggregation in the brain. The increase of alpha-secretase activity in the brain provides a plausible strategy to prevent Abeta formation. Concerning this possibility two transgenic mouse lines (FVB/N) have been created: mice over-expressing the bovine form of the alpha-secretase (ADAM10) and mice over-expressing an inactive form of the alpha-secretase (ADAM10-E348A-HA; ADAM10-dn). For behavioral examination a F1 ge…
P3‐039: Axonal neuritic pathology induces early presynaptic alterations in ps1/APP Alzheimer's mice hippocampus
2011
Loss of neurons in the hippocampus correlates with memory impairment in AD. Significant early reduction in the numerical density of hippocampal SOM interneurons was found in single (APPswe) and double (APPswe/ PS1dE9 and APPswe/TauP301S-G272V) transgenic models based on APP over expression and amyloid production. However, this inhibitory population was unaffected in age-matched single PS1 and tau transgenic mice as well as nontransgenic controls. Whereas SOM neuron loss in APPswe/PS1dE9 was associated to the onset of extracellular amyloid pathology in double APP/ tau mice this loss preceded plaque formation. Conclusions: As in human AD, somatostatin cell loss is a common early pathological …
Central cholinergic functions in human amyloid precursor protein knock-in/presenilin-1 transgenic mice.
2004
Alzheimer's disease is characterized by amyloid peptide formation and deposition, neurofibrillary tangles, central cholinergic dysfunction, and dementia; however, the relationship between these parameters is not well understood. We studied the effect of amyloid peptide formation and deposition on central cholinergic function in knock-in mice carrying the human amyloid precursor protein (APP) gene with the Swedish/London double mutation (APP-SL mice) which were crossbred with transgenic mice overexpressing normal (PS1wt) or mutated (M146L; PS1mut) human presenilin-1. APP-SLxPS1mut mice had increased levels of Abeta peptides at 10 months of age and amyloid plaques at 14 months of age while AP…
Effects of neuron-specific ADAM10 modulation in an in vivo model of acute excitotoxic stress.
2008
A disintegrin and metalloprotease (ADAM) 10 is the main candidate enzyme for the alpha-secretase processing of the amyloid precursor protein (APP). Neuron-specific ADAM10 overexpression proved beneficial in the APP[V717I] mutant Alzheimer mouse model [Postina R, Schroeder A, Dewachter I, Bohl J, Schmitt U, Kojro E, Prinzen C, Endres K, Hiemke C, Blessing M, Flamez P, Dequenne A, Godaux E, van Leuven F, Fahrenholz F (2004) A disintegrin-metalloproteinase prevents amyloid plaque formation and hippocampal defects in an Alzheimer disease mouse model. J Clin Invest 113:1456-1464]. Since Alzheimer patients have a high prevalence for epileptic seizures, we investigated the effects of ADAM10 modula…
Naturally occurring autoantibodies interfere with β-amyloid metabolism and improve cognition in a transgenic mouse model of Alzheimer's disease 24 h …
2013
There is evidence that naturally occurring antibodies directed against Aβ (nAbs-Aβ) have a role in Aβ-metabolism and Aβ-clearance. The presence of nAbs-Aβ leads to a reduction in amyloid fibrillation and thus a reduction in their toxicity. We investigated the effects of nAbs-Aβ in respect to oligomerization and used the Tg2576 transgenic mouse model in order to investigate the rapid effect with a single-dose (24 h) on oligomer breakdown and cytokine secretion along with immunohistochemical characterization of synaptic plasticity. nAbs-Aβ were able to reduce toxic oligomer concentration with an increase in Aβ-monomers. Cytokine secretion was significantly reduced. Synaptic plasticity was als…
Indication of a common origin of German and American Families with Familial Amyloidneuropathy Typ II
1999
Abstract The classification of familial amyloid neuropathies (FAP) is traditionally based on clinical and regional aspects. In the last 10 years more than 40 mutations of the transthyretin gene have been found to be responsible for different clinical forms of amyloidosis including familial FAP.FAP II is caused by a mutation on the codon 58 of the transthyretin gene. Only two american kindreds (the Maryland/German and the Ohio family) have previously been reported with FAP II starting in the 3rd or 4th decade by sensory disturbances of the hands typically as a carpal tunnel syndrome. We report on a german family with FAP II from the rhine river area south of Mainz. Four members with typical …
Physical exercise in the prevention and treatment of Alzheimer's disease
2020
Highlights • Low levels of physical activity are a risk factor associated with Alzheimer's disease. • Older adults who exercise are more likely to maintain cognition. • Exercise modulates amyloid β turnover, inflammation, synthesis, and release of neurotrophins, and cerebral blood flow.
LRP1 modulates APP trafficking along early compartments of the secretory pathway
2008
The amyloid beta peptide (A beta) is a central player in Alzheimer's disease (AD) pathology. A beta liberation depends on APP cleavage by beta- and gamma-secretases. The low density lipoprotein receptor related protein 1 (LRP1) was shown to mediate APP processing at multiple steps. Newly synthesized LRP1 can interact with APP, implying an interaction between these two proteins early in the secretory pathway. We wanted to investigate whether LRP1 mediates APP trafficking along the secretory pathway, and, if so, whether it affects APP processing. Indeed, the early trafficking of APP within the secretory pathway is strongly influenced by its interaction with the C-terminal domain of LRP1. The …
Multisystem Amyloidosis in a Coal Miner with Silicosis: Is Exposure to Silica Dust a Cause of Amyloid Deposition?
2022
The over-secretion of monoclonal immunoglobulin light chains by clonal B cells followed by the aggregation and extracellular deposition of fibrillar deposits are responsible forthe clinical course AL amyloidosis. It is well documented that silica significantly increases the number of immunoglobulin-secreting cells. In the present paper, we report on a coal miner with silicosis and fast progressing primary amyloidosis with predominantly heart, kidney, and lung manifestations. Severeheart failure due to myocardial hypertrophy resulted in the patient’s death. We conclude that long-term environmental silica exposure and silica deposition may contribute to the development of monoclonal gammopath…