Soluble amyloid precursor protein (sAPP) can recover GM6001 (GM)-induced deficits in Erk phosphorylation. (a) Representative Western blot of neural progenitor cells (NPCs) treated with inactive inhibitor (NC), GM6001, or GM6001 + recombinant sAPPα and probed for pErk (top) and total Erk (bottom). (b) Quantification of pErk/total Erk Western blots. (*P < 0.05, n = 4, analysis of variance with post hoc analysis). (c) Representative Western blot of NPCs treated as described above and probed for pAkt (top) and total Akt (bottom). (d) Quantification of pAkt/total Akt Western blots (n = 4).