Lutein treatment alters PI3K-AKT protein expression.
(A) Neurite outgrowth was abolished by PI3K inhibitor LY294002 (F(5,162) = 175.9, P < 0.01). (B) Western blot analysis of pan and phospho-AKT (S473) expression in the presence of lutein (5 μM) or DHA (10 μM) with (or without) LY294002 (10 μM) co-treatment (represented results of eight replications). (C) Quantification of pAKT expression. Lutein-mediated increase in pAKT expression was reversed by LY294002 co-treatment (F(5, 28) = 25, P < 0.01). (D) Quantification of pan AKT expression. Sole treatment with either micronutrient had no effect on AKT expression, while co-treatment with LY294002 significantly reduced AKT expression (F(5,29) = 23, P < 0.01); Statistical significance: *P < 0.05 and **P < 0.01, vs. control (one-way analysis of variance followed by the least significant difference post hoc test), data are expressed as the mean ± SEM, n = 8 measurements per group). CON: Control; LUT: lutein (5 μM); LUTLY: lutein (5 μM) + LY294002 (10 μM); DHA: docosahexaenoic acid (10 μM); DHALY: DHA (10 μM) + LY294002 (10 μM); LY: LY294002 (10 μM).