Age-related decrease in constructive activation of Akt/PKB in SAMP10 hippocampus

Aging is the greatest risk factor for neurodegenerative diseases such as Alzheimer's disease (AD). Age-dependent alterations of cell signaling play an important role in the onset of AD. The serine/threonine kinase Akt is a critical cell signaling to neuronal survival. Using the senescence-accelerated mouse SAMP10, we investigated the effect of aging on AKT signaling in hippocampus tissue. During aging, the expression of Akt mRNA and protein remained stable. However, the constructive phosphorylation of Akt(Ser473) displayed a continuous decrease after 6 months in SAMP10. When compared with the control SAMR1, aged SAMP10 mice showed significant reduced phosphorylation of Akt(Ser473). SAMP10 at the age of 6 months showed obvious deterioration in performance of learning and memory tasks. Thus, the data reported here suggested a potential link between the age-related alteration of Akts(Ser473) and the deterioration in performance of learning and memory tasks in SAMP10 mouse. (C) 2008 Elsevier Inc. All rights reserved.