Dynamics of Aβ42 reduction in plasma, CSF and brain of rats treated with the γ-secretase modulator, GSM-10h.

Background: Allosteric modulation of γ-secretase is an attractive therapeutic approach for the treatment of Alzheimer's disease. We recently identified a novel γ-secretase modulator, GSM-10h, which effectively lowers Aβ42 production in cells and in amyloid precursor protein transgenic mice.

Objective: Here, we describe the in vivo characterization of GSM-10h in a model of endogenous Aβ production.

TASTPM mice expressing amyloid precursor protein and presenilin-1 mutant transgenes are sensitive to γ-secretase modulation and amyloid-β₄₂ lowering by GSM-10h.

Background: Cleavage of the amyloid precursor protein (APP) by β-site APP-cleaving enzyme and γ-secretase results in the generation of amyloid-β (Aβ) peptides that aggregate and deposit as senile plaques in brains of Alzheimer disease patients. Due to the fundamental role γ-secretase plays in the proteolysis of a number of proteins including Notch, pharmacological inhibition of γ-secretase has been associated with mechanism-based toxicities. Therefore, efforts have focussed on the modulation of γ-secretase activity to selectively decrease levels of Aβ₄₂ peptide while avoiding deleterious activity on Notch processing.

Tricyclic azepine derivatives as selective brain penetrant 5-HT6 receptor antagonists.

Starting from a benzazepine sulfonamide 5-HT(6) receptor antagonist lead with limited brain penetration, application of a strategy of conformational constraint and reduction of hydrogen bond donor count led to a novel series of tricyclic derivatives with high 5-HT(6) receptor affinity and excellent brain:blood ratios.