Figure 4.

The 70% ethanol extract of Spirulina maxima (SM70EE) inhibits amyloid-β 1–42 (Aβ_1–42)-induced hyperphosphorylation of glycogen synthase kinase-3β (GSK-3β) by activating the Aβ_1–42-inhibited hippocampal BDNF/PI3K/Akt signaling pathway. (A) Levels of brain-derived neurotrophic factor (BDNF) in mouse hippocampus (n = 4 per group). (B,C) Mouse hippocampal lysates were used in western blot analyses to determine protein levels of (B) BDNF and (C) phosphorylated phosphatidylinositol-3 kinase (pPI3K), phosphorylated serine/threonine protein kinase (pAkt), and phosphorylated glycogen synthase kinase-3β (GSK-3β) (n = 3 per group). Protein levels were normalized to α-tubulin. Results were analyzed by one-way analysis of variance and Duncan’s multiple range test. The p-values in the multiple comparison results (e.g., a, b, c, and d) indicated significant differences among the groups (p < 0.05).