Article

Aß deposition and related pathology in an APP x PS1 transgenic mouse model of Alzheimer's disease

Neurology & GI CEDD, GlaxoSmithKline, Harlow, Essex, UK.
Histology and histopathology (Impact Factor: 2.24). 02/2008; 23(1):67-76.
Source: PubMed

ABSTRACT A transgenic mouse bearing mutant transgenes linked to familial forms of Alzheimer's disease (AD) for the amyloid precursor protein and presenilin-1 (TASTPM) showed Abeta plaque deposition and age-related histological changes in associated brain pathology. The Abeta present was of multiple forms, including species with a C-terminus at position 40 or 42, as well as an N-terminus at position 1 or truncated in a pyro-3-glutamate form. Endogenous rodent Abeta was also present in the deposits. Laser capture microdissection extracts showed that multimeric forms of Abeta were present in both plaque and tissue surrounding plaques. Associated with the Abeta deposits was evidence of an inflammatory response characterised by the presence of astrocytes. Also present in close association with the deposits was phosphorylated tau and cathepsin D immunolabelling. The incidence of astrocytes and of phosphorylated tau and cathepsin D load showed that both of these potential disease markers increased in parallel to the age of the mice and with Abeta deposition. Immunohistochemical labelling of neurons in the cortex and hippocampus of TASTPM mice suggested that the areas of Abeta deposition were associated with the loss of neurons. TASTPM mice, therefore, exhibit a number of the pathological characteristics of disease progression in AD and may provide a means for assessment of novel therapeutic agents directed towards modifying or halting disease progression.

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    • "A nanocrystal formulation of dantrolene (Lyotropic Therapeutics, Inc., [27]) was administered intraperitoneally (IP, 10 mg/kg in sterile water) to AD-Tg and NonTg mice at two time points: (1) daily injections for 4 weeks starting at 2 months of age for the 3xTg-AD mice (corresponding to plaque-free stage); and (2) daily injections for 4 weeks starting at 5 months for the TASTPM (coinciding with moderate plaque formation and onset of cognitive deficits; [26], [28]. Control mice were administered 0.9% saline daily. "
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    • "Microglial activation coincided with synaptic pathology, followed later by fibrillary tau pathology and astrogliosis [48]. Although Howlett and colleagues found no up-regulation of microglial CD11b in TASTPM mice (double APP/PS1 transgenic), expression of Iba-1 was greatly increased [9] [49], suggesting a change in activation state. "
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