Soybean-derived phosphatidylinositol recovers amyloid β protein-induced neurotoxicity in cultured rat hippocampal neurons

Abstract

Effects of soybean-derived phosphatidylinositol (PI) on amyloid β protein (10 nM Aβ 25–35)-induced changes in Cl −-ATPase activity, intracellular Cl − concentration ([Cl −] i) and glutamate neurotoxicity were examined using cultured rat hippocampal neurons. Soybean-derived PI (≥5 nM) dose-dependently recovered Aβ-induced decrease in neuronal Cl −-ATPase activity without any changes in the activities of Na +,K +-ATPase and anion-insensitive Mg 2+-ATPase. Soybean-derived PI reduced Aβ-induced elevation of [Cl −] i as assayed using a Cl −-sensitive fluorescent dye, and prevented Aβ-induced aggravation of glutamate neurotoxicity assayed by mitochondrial 2-(2-methoxy-4-nitrophenyl)-3-(4-nitrophenyl)-5-(2,4-disulfophenyl)-2 H-tetrazolium, monosodium salt reducing activity and plasma membrane lactate dehydrogenase release. These data suggest that soybean-derived PI may be useful as a therapeutic and/or preventive strategy for Alzheimer's disease.