IC50: 7 nM (Aβ, in HEK293 cells)

BMS-299897 reduces the levels of each of the Aβ peptides. At 1 μM, BMS-299897 decreases these peptides to levels ranging from 20 to 50% of the vehicle control. BMS-299897 treatment reduces the portion of QD-BDNF signals moving in the retrograde direction (p=0.0198) with a concomitant increase in the portion of signals moving in the anterograde direction (p=0.0147).

BMS-299897 shows dose- and time-dependent reductions of amyloid β-peptide (Aβ) in brain, cerebrospinal fluid (CSF), and plasma in young transgenic mice, with a correlation between brain and CSF Aβ levels. BMS-299897 reduces both brain and plasma Aβ _1-40 in APP-YAC mice and increases brain concentrations of APPcarboxy-terminal fragments, consistent with γ-secretase inhibition. BMS-299897, attenuates this Aβ _25-35 -induced Aβ _1-42 seeding and toxicity. BMS-299897 is administered at 0.1-1 nmol/mouse, concomittantly with Aβ _25-35 (9 nmol) in male Swiss mice. After one week, the contents in Aβ _1-42 and Aβ _1-40 , and the levels in lipid peroxidation are analyzed in the mouse hippocampus. Mice are submitted to spontaneous alternation, passive avoidance and object recognition to analyze their short- and long-term memory abilities. Aβ _25-35 increases Aβ _1-42 content (+240%) but fails to affect Aβ _1-40 . BMS-299897 blocks the increase in Aβ _1-42 content and decreased Aβ _1-40 levels significantly. The compound does not affect Aβ _25-35 -induced increase in hippocampal lipid peroxidation. Behaviorally, BMS-299897 blocks the Aβ _25-35 -induced deficits in spontaneous alternation or novel object recognition, using a 1 h intertrial time interval. The co-administration of the γ-secretase inhibitor BMS-299897, in the 0.1-1 μmol/mouse dose-range, completely blocks the Aβ _25-35 -induced increase in Aβ _1-42 content.