E 2012 is a potent γ-secretase modulator.IC50 value:Target: γ-secretaseIn the present study, 9 dogs were treated with a single dose of the γ-secretase modulator E2012, the γ-secretase inhibitor LY450139, or vehicle with a dosing interval of 1 week. The isoform Aβ(1-37) was significantly increased in a dose-dependent manner in response to treatment with E2012, while Aβ(1-39), Aβ(1-40) and A(1-42) decreased [1].E2012, a gamma secretase modulator without affecting Notch processing, aimed at Alzheimer's disease by reduction of amyloid β-42, induced cataract following repeated doses in the rat.E2012 inhibits 3β-hydroxysterol δ24-reductase (DHCR24) at the final step in the cholesterol biosynthesis. In vivo lenticular concentration of E2012 after 13-week repeated dose with cataract was well above those where inhibition was observed in vitro.E2012 induces cataract in the rat by inhibiting DHCR24 at the final step of cholesterol synthesis with associated elevation in desmosterol within the lens, preceded by desmosterol changes that would serve as a predictive safety biomarker for lenticular opacity [2].
[1]. Nakano-Ito K, et al. E2012-induced cataract and its predictive biomarkers. Toxicol Sci. 2014 Jan;137(1):249-58. [2]. Portelius E, Van Broeck B, Andreasson U, Gustavsson MK, Mercken M, Zetterberg H, Borghys H, Blennow K.Acute effect on the Aβ isoform pattern in CSF in response to γ-secretase modulator and inhibitor treatment in dogs.J Alzheimers Dis. 2010;21(3):1005-12.