Abstract
Extra-virgin olive oil (EVOO) is one of the main elements of Mediterranean diet. Several studies have suggested that EVOO has several health promoting effects that could protect from and decrease the risk of Alzheimer's disease (AD). In this study, we investigated the effect of consumption of EVOO-enriched diet on amyloid- and tau-related pathological alterations that are associated with the progression of AD and cerebral amyloid angiopathy (CAA) in TgSwDI mice. Feeding mice with EVOO-enriched diet for 6 months, beginning at an age before amyloid-beta (A beta) accumulation starts, has significantly reduced total A beta and tau brain levels with a significant improvement in mouse cognitive behavior. This reduction in brain A beta was explained by the enhanced A beta clearance pathways and reduced brain production of A beta via modulation of amyloid-p precursor protein processing. On the other hand, although feeding mice with EVOO-enriched diet for 3 months, beginning at an age after A beta accumulation starts, showed improved clearance across the blood-brain barrier and significant reduction in A beta, levels, it did not affect tau levels or improve cognitive functions of TgSwDI mouse. Collectively, results of this study suggest that the long-term consumption of EVOO-containing diet starting at early age provides a protective effect against AD and its related disorder CAA. (C) 2015 Elsevier Inc. All rights reserved.