Reading...
Play button
Play button
Use LEFT and RIGHT arrow keys to navigate between flashcards;
Use UP and DOWN arrow keys to flip the card;
H to show hint;
A reads text to speech;
24 Cards in this Set
- Front
- Back
|
AD pathology
|
deposition of beta amyloid plaques and neurofibrillary tangles in the HC and cerebral cortex
|
|
|
Abeta peptides how generated?
|
through endoproteolytic cleavages of neuronal Abeta precursor protein (APP) by two membrane bound enzyme activities termed BACE1 and gamma secretase
|
|
|
neuronal loss in AD
|
neuronal loss begins in the entorhinal cortex and the CA1 subfield
|
|
|
mitochondrial function
|
reduced mitochondrial function during aging; can lead to pathological concentrations of ROS production
|
|
|
neurofibrillary tangles
|
located within cell bodies and proximal dendrites and within filamentous swellings in distal axons and synaptic terminals
|
|
|
hyperphosphorylated isoforms of tau
|
microtubule-associated tau assembles into poorly soluble paired helical filaments
|
|
|
a beta
|
a 4 kD amyloid peptide derived by cleavage of the amyloid precursor protein; A beta monomers form oligomers and multimers
|
|
|
APP
|
type 1 transmembrane protein expressed in many different cell types
|
|
|
presenillins
|
PS1 and PS2 encode multipass transmembrane proteins processed to stable N term and C term fragments. PS1 influences APP processing and is a critical element of the gamma-secretase complex; missense mutations that result in single AA substitutions lead to increased generation of A beta peptide
|
|
|
the first mutation causing familil form of the disease
|
amyloid precursor protein gene on chromosome 21
|
|
|
ApoE
|
in 1993 found an association between the apolipoprotein E allele increases the risk of disease
|
|
|
ApoE what is it
|
acts as a cholesterol transporter in the brain also is essential for Abeta deposition promoting plaque formation
|
|
|
central hypothesis for the cause of Alzheimer's disease
|
amyloid cascade hypothesis: an imbalance between the prodction and clearance of the Abeta in the brain
|
|
|
APP mutations
|
lead to increased in Abeta production
|
|
|
tau
|
tau is a normal axonal protein that binds to microtubules and promotes microtubule assembly and stability
|
|
|
tau hyperphosphorylation
|
leads to sequestration of normal tau and causes disassembly of microtubules and thus impaired axonal transport
|
|
|
tau aggregation
|
tau becomes prone to aggregation into insoluble fribils in tangles
|
|
|
APOE
|
risk allele for late onset AD
|
|
|
APOE function
|
cholesterol carrier in the brain so it delivers cholsterol and other essential lipids to neurons through low density lipoprotein receptors produced mostly by astrocytes
|
|
|
APOE receptors interact with APP
|
to modulate its trafficking and processing to A beta; aka increased APP endocytic trafficking and processing to A beta
|
|
|
amyloid-beta produced where
|
within the endoplasmic reticulum and golgi system and secreted as part of the constitiutive secretory pathway
|
|
|
HD caused by
|
expanded CAG repeats coding for polyglutamine in the Huntingtin gene
|
|
|
HD degeneration
|
shows selective neuronal vulneravility; most prominent in the caudate and putamen
|
|
|
HD and basal ganglia
|
the medium spiny neurons
|
