D-Amino Acid Oxidase Inhibitor III

A cell-permeable pyrazolocarboxylic acid that acts as a selective D-amino acid oxidase (DAO/DAAO/DAMOX/OXDA) inhibitor (IC50 = 910 nM against human DAO; [D-ser] = 10 mM) and effectively protects DAO overexpressing cultures from oxidative stress-induced cell death upon D-Ser (50 mM) exposure (ED50 ≤3.95 µM), while exhibiting little affinity toward NMDAR glycine binding site (6% inhibition at 100 µM), nor inhibitory activity against D-aspartate oxidase (DDO/DSOX; 43% inhibition at 100 µM) or serine racemase (no inhibition at 50 µM). AS057278 is orally available (plasma Cmax = 8.089 µg/mL; t1/2 = 7.21 h; tmax = 1 h post 10 mg/mL oral dosing in rats) and can cross blood-brain barrier (1.622 and 0.578 µg/g brain tissue, respectively, 15 and 60 min post single 10 mg/kg i.v. dosing in rats). Effectively prevents PCP (phencyclidine) from suppressing PPI (prepulse inhibition; prepulse noise = 82 dB, startle noise = 120 dB) response in mice via either long-term oral administration (93% and 70% of no-PCP control PPI level, respectively, with or without 28-day b.i.d, treatment at 20 mg/kg/12 h) or single acute heavy oral dosing (93% and 53% of no-PCP control PPI level, respectively, with or without 80 mg/kg dosing) 60 min prior to PCP treatment (8 mg/kg i.p.) in vivo.