Figure 5.

Proposed mechanism whereby SM70EE ameliorates learning and memory impairments in mice with an intracerebroventricular injection of amyloid-β 1–42 (Aβ_1–42). The 70% ethanol extract of Spirulina maxima (SM70EE) inhibits phosphorylation of GSK3-β, which is regulated by the activation of the brain-derived neurotrophic factor (BDNF)/phosphatidylinositol-3 kinase (pPI3K)/serine/threonine protein kinase (Akt) signaling pathway. → indicates stimulation; ⊥, inhibition, ?, unclear action; APP, amyloid precursor protein; BACE1, β-site APP-cleaving enzyme 1; M1AChR, muscarinic acetylcholine receptor M1; PKC, protein kinase C; TrkB, tropomyosin receptor kinase B.