Tg-SwDI transgenic mice exhibit novel alterations in AbetaPP processing, Abeta degradation, and resilient amyloid angiopathy.
Alzheimer's disease (AD) is characterized by the accumulation of extracellular insoluble amyloid, primarily derived from polymerized amyloid-beta (Abeta) peptides. We characterized the chemical composition of the Abeta peptides deposited in the brain parenchyma and cerebrovascular walls of triple transgenic Tg-SwDI mice that produce a rapid and profuse Abeta accumulation. The processing of the N- and C-terminal regions of mutant AbetaPP differs substantially from humans because the brain parenchyma accumulates numerous, diffuse, nonfibrillar plaques, whereas the thalamic microvessels harbor overwhelming amounts of compact, fibrillar, thioflavine-S- and apolipoprotein E-positive amyloid deposits. The abundant accretion of vascular amyloid, despite low AbetaPP transgene expression levels, suggests that inefficient Abeta proteolysis because of conformational changes and dimerization may be key pathogenic factors in this animal model. The disruption of amyloid plaque cores by immunotherapy is accompanied by increased perivascular deposition in both humans and transgenic mice. This analogous susceptibility and response to the disruption of amyloid deposits suggests that Tg-SwDI mice provide an excellent model in which to study the functional aftermath of immunotherapeutic interventions. These mice might also reveal new avenues to promote amyloidogenic AbetaPP processing and fundamental insights into the faulty degradation and clearance of Abeta in AD, pivotal issues in understanding AD pathophysiology and the assessment of new therapeutic agents.
Van Vickle
Gregory D
GD
The Longtine Center for Molecular Biology and Genetics, Sun Health Research Institute, Sun City, AZ 85351, USA.
Esh
Chera L
CL
Daugs
Ian D
ID
Kokjohn
Tyler A
TA
Kalback
Walter M
WM
Patton
R Lyle
RL
Luehrs
Dean C
DC
Walker
Douglas G
DG
Lue
Lih-Fen
LF
Beach
Thomas G
TG
Davis
Judianne
J
Van Nostrand
William E
WE
Castaño
Eduardo M
EM
Roher
Alex E
AE
D000544:Alzheimer Disease / Q000378:metabolism* / Q000473:pathology; D016229:Amyloid beta-Peptides / Q000378:metabolism*; D016564:Amyloid beta-Protein Precursor / Q000378:metabolism; D000818:Animals; D001057:Apolipoproteins E / Q000378:metabolism; D052160:Benzothiazoles; D016657:Cerebral Amyloid Angiopathy / Q000378:metabolism* / Q000473:pathology; D019281:Dimerization; D004195:Disease Models, Animal; D006801:Humans; D051379:Mice; D008822:Mice, Transgenic; D058225:Plaque, Amyloid / Q000378:metabolism* / Q000473:pathology; D011487:Protein Conformation; D013844:Thiazoles / Q000378:metabolism
D016229:Amyloid beta-Peptides; D016564:Amyloid beta-Protein Precursor; D001057:Apolipoproteins E; D052160:Benzothiazoles; D013844:Thiazoles; C009462:thioflavin T