Identification of myo-inositol hexakisphosphate (IP6) as a β-secretase 1 (BACE1) inhibitory molecule in rice grain extract and digest

Alzheimer's disease (AD) is widely considered to be caused by amyloid-beta peptide (Ab) accumulation in the brain. Ab is excised from amyloid-beta precursor protein through sequential cleavage by beta-secretase 1 (BACE1) and gamma-secretase. Thus, BACE1 inhibition could prevent Ab accumulation. Here, we identified myo-inositol hexakisphosphate (IP6) as a BACE1 inhibitory molecule in rice grain extract and digest. The rice digest and IP6 significantly inhibited A beta production in neuroblastoma cells without cytotoxicity. These results suggested that rice components, including IP6, may be promising starting materials for the development of potent and safe drugs and/or food to prevent AD. (C) 2014 The Authors. Published by Elsevier B.V. on behalf of the Federation of European Biochemical Societies.