Fig. 5.

ApoE4-mediated reduction in sAPPα levels is reversed by various inhibitors. A172 cells were transfected with ApoE4 in the presence of epoxomicin (5 μM), MG132 (5 μM), disulfiram (20 μM), z-VAD (40 μM), or DAPT (10 μM). (A and B) Cell culture media were collected and either assayed for sAPPα (A) as described in SI Materials and Methods or subjected to IP with an N-terminal anti-APP antibody followed by SDS/PAGE and WB to detect sAPPα (B). FO3 and FO5 (C and D) reverse ApoE4-mediated reduction in sAPPα levels. Twenty-four hours after transfecting A172 cells with ApoE4, culture medium was changed, and F03 (C) or F05 (D) was added. After an additional 24 h, cell culture media were collected and assayed for sAPPα. Data (mean ± SE) are expressed in arbitrary units of sAPPα released into the media (*P < 0.05).