[permalink] [id link]
Aβ is the main constituent of brain parenchymal and vascular amyloid, it contributes to cerebrovascular lesions and is neurotoxic .< ref name =" pmid9514588 "> It is unresolved how Aβ accumulates in the central nervous system and subsequently initiates the disease of cells.
from
Wikipedia
Some Related Sentences
Aβ and is
* The hypothesis that beta amyloid protein is key to IBM has been supported in a mouse model using an Aβ vaccine that was found to be effective against inclusion body myositis in mouse models.
Although this vaccine is likely not safe for human use, it still shows that attacking Aβ has efficacy in mice against IBM.
Its exact cause remains unknown, but the disease is identified as a protein misfolding disease and is associated with toxic aggregations of the amyloid beta ( Aβ ) peptide, a fragment of the larger amyloid precursor protein.
Disabling Aβ aggregation using small molecules is regarded as a promising approach to the development of therapeutic drugs for treating Alzheimer's patients.
While Aβ's role in LTD regulation has not been clearly understood, it has been found that soluble Aβ facilitates hippocampal LTD and is mediated by a decrease in glutamate recycling at hippocampal synapses.
Another chemical in the brain that Aβ regulates is JNK ; this chemical halts the extracellular signal-regulated kinases ( ERK ) pathway, which normally functions as memory control in the brain.
Another way Aβ causes cell death is through the phosphorylation of AKT ; this occurs as the element phosphate is bound to several sites on the protein.
GSK-3 is thought to directly promote Aβ production and to be tied to the process of the hyperphosphorylation of tau proteins, which leads to the tangles.
Substance P, involved in the transmission of pain signals, is usually expressed by Aδ and C fibers, but following peripheral nerve damage, substance P is expressed by Aβ fibers ( Bittar et al., 2005 ).
Amyloid beta ( Aβ or Abeta ) is a peptide of 36 – 43 amino acids that is processed from the Amyloid precursor protein.
While best known as a component of amyloid plaques in association with Alzheimer's disease, evidence has been found that Aβ is a highly multifunctional peptide with significant non-pathological activity.
Aβ is the main component of amyloid plaques ( deposits found in the brains of patients with Alzheimer's disease ).
Aβ circulates in plasma, cerebrospinal fluid ( CSF ) and brain interstitial fluid ( ISF ) mainly as soluble Aβ40 Senile plaques contain both Aβ40 and Aβ42, while vascular amyloid is predominantly the shorter Aβ40.
Aβ and brain
Some new evidence indicates that disruption of the blood – brain barrier in Alzheimer's Disease patients allows blood plasma containing amyloid beta ( Aβ ) to enter the brain where the Aβ adheres preferentially to the surface of astrocytes.
Some of the most common naturally occurring brain toxins that lead to neurotoxicity as a result of excessive dosage are: Beta amyloid ( Aβ ), Glutamate and Oxygen radicals.
Aβ was found to cause neurotoxicity and cell death in the brain when present in high concentrations.
Aβ was found manipulating the level of nicotine in the brain along with the MAP kinase, another signaling receptor, to cause cell death.
Under normal physiology Aβ is cleared from the brain by four pathways: ( 1 ) endocytosis by astrocytes and microglial cells, ( 2 ) enzymatic degradation by neprilysin or insulysin ( 3 ) cleared by way of the blood brain barrier or ( 4 ) drained along periarterial spaces.
Aβ and amyloid
Enzymes act on the amyloid precursor protein and cut it into Aβ fragments, which then aggregate to form senile plaques characteristic of Alzheimer's patients.
Additionally, researchers have recently discovered a new mechanism ( which involves LTD ) linking soluble amyloid beta protein ( Aβ ) with the synaptic injury and memory loss related to AD.
Similar plaques appear in some variants of Lewy body dementia and in inclusion body myositis ( a muscle disease ), while Aβ can also form the aggregates that coat cerebral blood vessels in cerebral amyloid angiopathy.
Significant efforts have been focused on the mechanisms responsible for Aβ production, including the proteolytic enzymes alpha-and ß-secretases which generate Aβ from its precursor protein, APP ( amyloid precursor protein ).
Aβ is formed after sequential cleavage of the amyloid precursor protein ( APP ), a transmembrane glycoprotein of undetermined function.
NMR-derived models of a 26-aminoacid polypeptide from amyloid beta ( Aβ 10-35 ) show a collapsed coil structure devoid of significant secondary structure content.
APP is best known as the precursor molecule whose proteolysis generates beta amyloid ( Aβ ), a 37 to 49 amino acid peptide whose amyloid fibrillar form is the primary component of amyloid plaques found in the brains of Alzheimer's disease patients.
Mutations in critical regions of Amyloid Precursor Protein, including the region that generates amyloid beta ( Aβ ), cause familial susceptibility to Alzheimer's disease.
In mice, netrin has also been associated with the regulation of ( Aβ ) peptide, which is responsible for amyloid plaques in Alzheimer ’ s disease.
Sporadic forms of CAA have been further characterized into two types based on deposition of amyloid β-protein ( Aβ ) in cortical capillaries.
Aβ and contributes
High concentrations of misfolded Aβ < sub > 42 </ sub > causes protein oligomer growth leading to aggregation that in turn contributes to Aβ misfolding.
Aβ and cerebrovascular
Increases in either total Aβ levels or the relative concentration of both Aβ < sub > 40 </ sub > and Aβ < sub > 42 </ sub > ( where the former is more concentrated in cerebrovascular plaques and the latter in neuritic plaques ) have been implicated in the pathogenesis of both familial and sporadic Alzheimer's disease.
Aβ and lesions
Aβ and how
Later that year, Folding @ home began simulations of various Aβ fragments in order to determine how various natural enzymes affect the structure and folding of Aβ.
Aβ and accumulates
The logical inference is that because Aβ accumulates excessively in Alzheimer's disease its precursor, APP, would be elevated as well.
Aβ and central
A number of genetic, cell biology, biochemical and animal studies support the concept that Aβ plays a central role in the development of Alzheimer ’ s disease pathology.
Aβ and system
This stimulates the host immune system to recognize and attack Aβ, or provide antibodies that either prevent plaque deposition or enhance clearance of plaques or Aβ oligomers.
Aβ and disease
In 2011, Folding @ home completed simulations of several mutations of Aβ that appear to stabilize the aggregate formation, which could aid in the development of therapeutic drug approaches to the disease as well as greatly assisting with experimental NMR spectroscopy studies of the oligomers.
GSK-3 activity has been associated with both pathological features of Alzheimer ’ s disease, namely the buildup of Amyloid-β ( Aβ ) deposits and the formation of neurofibrillary tangles.
Several potential activities have been discovered for Aβ that are not associated with disease, including activation of kinase enzymes, protection against oxidative stress, regulation of cholesterol transport, functioning as a transcription factor, and anti-microbial activity ( potentially associated with Aβ's pro-inflammatory activity ).
The Aβ < sub > 40 </ sub > form is the more common of the two, but Aβ < sub > 42 </ sub > is the more fibrillogenic and is thus associated with disease states.
0.256 seconds.