LY411575

2 years -80 in solvent

Orally

primary and immortalized KS cells

1–10 mg/kg

0.078 nM (membrane-based), 0.078 nM (membrane-based), 0.078 nM (membrane-based), 0.078 nM (membrane-based), 0.078 nM (membrane-based), 0.078 nM (membrane-based)

10 mg/kg oral dose of LY-411575 decreases brain and plasma Abeta40 and -42 dose-dependently. [1] LY-411575 reduces cortical Abeta40 in young (preplaque) transgenic CRND8 mice (ED50 0.6 mg/kg) and produces significant thymus atrophy and intestinal goblet cell hyperplasia at higher doses (>3 mg/kg). The therapeutic window is similar after oral and subcutaneous administration and in young and aged CRND8 mice. Both the thymus and intestinal side effects are reversible after a 2-week washout period. Three-week treatment with 1 mg/kg LY411575 reduces cortical Abeta40 by 69% without inducing intestinal effects, although a previously unreported change in coat color is observed. [3]

Assays for Abeta and NICD, Procedures for measuring gamma-secretase activity in membranes prepared from HEK293 cells expressing APP have been described previously (Zhang L et al Biochemistry 40, 5049-5055). Intact HEK293 cells expressing either APP or NdeltaE are treated with various concentrations of LY- 411, 575 for 4 hours at 37 C. In the case of cells expressing NdeltaE, cells are lysed, the cell lysates are separated on a 4–12% NuPAGE gel, and the processed NICD fragment is detected via Western blot with a cleavage site-specific antibody. The inhibition of NICD production is quantified by spot densitometric analysis using FluorChem. In the case of cells expressing APP, the conditioned medium is collected, centrifuged at 10, 000, g for 5 minutes to remove cell debris, and stored at -20 C prior to the determination of Abeta levels. Abeta40 and -42 produced in HEK293 membrane- and cell-based assays, as well as plasma Abeta40 and cortex Abeta40 from TgCRND8 mice, are analyzed without pretreatment using an ectrochemiluminescence detection-based immunoassay. Plasma Abeta42 is measured by enzyme-linked immunosorbent assay. A commercially available enzyme-linked immunosorbent assay kit is used to measure cortex Abeta42 according to the manufacturer''s instructions.

LY411575 is a potent γ-secretase inhibitor with IC50 of 0.078 nM/0.082 nM (membrane/cell-based), also inhibits Notch cleavage with IC50 of 0.39 nM in APP or NΔE expressing HEK293 cells. LY411575 induces apoptosis.