Candidate factor glucose-6-phosphate isomerase (GPI) increases neural differentiation. (A) GPI (0.5 μg/ml and 1 μg/ml), AICAR CM (A-CM) and RA/FSK significantly increased the proportion of aNPCs differentiating into Tuj1-positive neurons as compared to Mock and Vehicle CM (V-CM) treatment conditions (*p < 0.05). (B) GPI (1 μg/ml) and AICAR CM also enhanced gliogenesis as evidenced by an increased number of GFAP-positive astrocytes as compared to Mock and Vehicle CM treatment (*p < 0.05). (C,E,G) Representative photomicrographs of (C) V-CM, (E) A-CM, and (G) GPI treated aNPCs expressing neuronal marker Tuj1 (red), nuclei were stained with 4′,6-diamidino-2-phenylindole (DAPI), blue. (D,F,H) Representative photomicrographs of (D) V-CM, (F) A-CM, and (H) GPI treated cells expressing astroglial marker GFAP (red), nuclei were stained with DAPI (blue).