DAPT

2 years -80 in solvent

Administered via p.o.

SK-MES-1

<=100 mg/kg

20 nM [1], 20 nM [1], 20 nM [1], 20 nM [1], 20 nM [1], 20 nM [1]

DAPT administration (100mg/kg) leads to a robust and sustained pharmacodynamic effect in PDAPP mice that DAPT levels in the brain exceeds 100 ng/g within 1 hour and persists up to 18 hours after administration, with peak levels of 490 ng/g observed after 3 hour. And during the period, DAPT (100 mg/kg) also reduces the cortical total Abeta and Abeta42, in a dose-dependent manner with a 50% reduction. [1] In rat cerebral cortexes, DAPT (40 mg/kg) suppresses the LPS-induced activity of gamma-secretase and increases the cell apoptosis with the prolonged neuroinflammation. [3]

In vitro Abeta reduction assays, Human embryonic kidney cells (American Type Culture Collection CRL-1573), transfected with the gene for APP751 (HEK 293) are used for routine Abeta reduction assays. Cells are plated in 96-well plates and allowed to adhere overnight in Dulbecco's modified Eagle medium (DMEM) supplemented with 10% heat-inactivated fetal bovine serum. DAPT are diluted from stock solutions in dimethylsulfoxide (DMSO) to yield a final concentration equal to 0.1% DMSO in media. Cells are pre-treated for 2 hours at 37 C with DAPT, media are aspirated off and fresh compound solutions applied. After an additional 2-hour treatment period, conditioned media is drawn off and analyzed by a sandwich ELISA (266–3D6) specific for total Abeta. Reduction of Abeta production is measured relative to control cells treated with 0.1% DMSO and expressed as a percentage inhibition. Data from at least six doses in duplicate are fitted to a four-parameter logistical model using XLfit software in order to determine tency. Human and PDAPP mouse neuronal cultures are grown in serum-free media to enhance their neuronal characteristics, and appeared to be greater than 90% neurons after maturation prior to use. Conditioned media to establish baseline Abeta values are collected by adding fresh media to each well and incubated for 24 hours at 37 C in the absence of DAPT. Cultures are then treated with fresh media containing DAPT at the desired range of concentrations for an additional 24 hours at 37 C, and conditioned media collected. For the measurement of total Abeta, samples are analyzed with the same ELISA (266–3D6) as used for the HEK 293 cell assays. Analyses of samples for Abeta42 production are performed by a separate ELISA (21F12–3D6) that utilizes a capture antibody specific for the Abeta42 C-terminus. Inhibition of production for both total Abeta and Abeta42 are determined by the difference between the values for the compound treatment and baseline periods. After plotting percentage inhibition versus DAPT concenion, data are analyzed with XLfit software, as above, to determine potency.

DMSO 87 mg/mL, Water <1 mg/mL, Ethanol 50 mg/mL

(S)-tert-butyl 2-((S)-2-(2-(3, 5-difluorophenyl)acetamido)propanamido)-2-phenylacetate