Rosiglitazone attenuates learning and memory deficits in Tg2576 Alzheimer mice


BIBLIOGRAPHIC THERAPEUTIC AGENT ANIMAL MODEL EXPERIMENTAL DESIGN OUTCOMES

Bibliographic

Year of Publication:
2006
Contact PI Name:
Ward A. Pedersen
Contact PI Affiliation:
Department of Pathology, Creighton University Medical Center, Omaha, Nebraska, USA
Primary Reference (PubMED ID):
Funding Source:
Alzheimer's Association
United States Department of Veterans Affairs (VA)
Nebraska Tobacco Settlement Biomedical Research Development Fund
National Institute on Aging (NIA)
Study Goal and Principal Findings:

The thiazolidinediones, such as rosiglitazone, increase peripheral insulin sensitivity and their use is proposed for the treatment of Alzheimer’s disease (AD). However, the mechanisms underlying the potential beneficial effects of rosiglitazone in AD remain unclear. In this report the authors demonstrate that rosiglitazone attenuates spatial learning and memory deficits in the Tg2576 transgenic mouse model of AD. The authors further show that rosiglitazone administration ameliorated the age –dependent peripheral insulin resistance and increased serum corticosterone levels exhibited by fasting Tg2576 mice. These data suggest that the beneficial effects of rosiglitazone on cognitive function of Tg2576 mice may be, at least partially, due to improved regulation of glucocorticoid levels. When untreated Tg2576 mice were administered metyrapone, a drug that blocks glucocorticoid production, their spatial learning and memory abilities and serum corticosterone levels were similar to those of rosiglitazone-treated mice- thus supporting the connection between glucocorticoid levels-rosiglitazone treatment and cognitive function.  In addition, the authors report that that rosiglitazone attenuated reductions in insulin-degrading enzyme (IDE) mRNA and activity, and reduced beta amyloid peptide 42 (Aβ)42 levels without affecting beta amyloid deposition, in the brains of Tg2576 mice. These results demonstrate that rosiglitazone attenuates learning and memory deficits in Tg2576 mice and suggest that the effects of the drug on learning and memory, brain IDE levels, and brain Aβ42 levels in the mice may be due to its glucocorticoid-lowering actions. While the mechanisms remain to be elucidated, an implication of these results is that rosiglitazone may be effective at attenuating changes in the brain leading to cognitive dysfunction in AD. Supporting this therapeutic hypothesis are clinical studies showing that rosiglitazone prevents cognitive decline in patients with early AD (see below –Watson et,al., 2005).

Bibliographic Notes:
For data on a clinical study of rosiglitazone on cognition and plasma levels of the APP derivative β-amyloid (Aβ) in humans with aMCI and early AD see the following: Watson et al., 2005 G.S. Watson, B.A. Cholerton, M.A. Reger, L.D. Baker, S.R. Plymate, S. Asthana, M.A. Fishel, J.J. Kulstad, P.S. Green, D.G. Cook, S.E. Kahn, M.L. Keeling, S. Craft Preserved cognition in patients with early Alzheimer disease and amnestic mild cognitive impairment during treatment with rosiglitazone: a preliminary study Am. J. Geriatr. Psychiatry, 13 (2005), pp. 950–958.

Therapeutic Agent

Therapeutic Information:
Therapy Type:
Small Molecule
Therapeutic Agent:
Rosiglitazone
Therapeutic Target:
Peroxisome Proliferator-Activated Receptor gamma (PPAR gamma)

Animal Model

Model Information:
Species:
Mouse
Model Type:
APP
Strain/Genetic Background:
Not Reported

Experimental Design

Is the following information reported in the study?:
Power/Sample Size Calculation
Randomized into Groups
Blinded for Treatment
Blinded for Outcome Measures
Pharmacokinetic Measures
Pharmacodynamic Measures
Toxicology Measures
ADME Measures
Biomarkers
Dose
Formulation
Route of Delivery
Duration of Treatment
Frequency of Administration
Age of Animal at the Beginning of Treatment
Age of Animal at the End of Treatment
Sex as a Biological Variable
Study Balanced for Sex as a Biological Variable
Number of Premature Deaths
Number of Excluded Animals
Statistical Plan
Genetic Background
Inclusion/Exclusion Criteria Included
Conflict of Interest
Experiment Notes

Dose was determined in tolerability studies reported in the following: Q.N. Diep, M.E. Mabrouk, J.S. Cohn, D. Endemann, F. Amiri, A. Virdis, M.F. Neves, E.L. Schiffrin
Structure, endothelial function, cell growth, and inflammation in blood vessels of angiotensin II-infused rats: role of peroxisome proliferator-activated receptor-γ Circulation, 105 (2002), pp. 2296–2302.

Outcomes

Outcome Measured
Outcome Parameters
Behavioral
Radial Arm Water Maze
Biochemical
Serum-Corticosterone
Insulin Degrading Enzyme (IDE) mRNA
Insulin Degrading Enzyme (IDE)
Brain-beta Amyloid Peptide 40
Brain-beta Amyloid Peptide 42

Source URL: http://alzped.nia.nih.gov/rosiglitazone-attenuates