ABSTRACT
Synthesis, SAR and evaluation of styrenyl quinazolinones as novel gamma secretase modulators are presented in this communication. Starting from literature and in-house leads we evaluated a range of quinazolinones which showed good modulation of γ-secretase activity.
Subject(s)
Amyloid Precursor Protein Secretases/metabolism , Amyloid beta-Peptides/antagonists & inhibitors , Quinazolinones/chemistry , Quinazolinones/pharmacology , Alzheimer Disease/drug therapy , Alzheimer Disease/enzymology , Alzheimer Disease/metabolism , Amyloid beta-Peptides/metabolism , Animals , Cell Line , Humans , Inhibitory Concentration 50 , Peptide Fragments/antagonists & inhibitors , Peptide Fragments/metabolism , Protein Binding , Quinazolinones/pharmacokinetics , Rats , Rats, Sprague-DawleyABSTRACT
The development of a novel series of purines as gamma-secretase modulators for potential use in the treatment of Alzheimer's disease is disclosed herein. Optimization of a previously disclosed pyrimidine series afforded a series of potent purine-based gamma-secretase modulators with 300- to 2000-fold in vitro selectivity over inhibition of Notch cleavage and that selectively reduces Alphabeta42 in an APP-YAC transgenic mouse model.
Subject(s)
Alzheimer Disease/drug therapy , Amyloid Precursor Protein Secretases/metabolism , Amyloid beta-Peptides/antagonists & inhibitors , Peptide Fragments/antagonists & inhibitors , Purines/chemistry , Purines/therapeutic use , Amyloid Precursor Protein Secretases/genetics , Amyloid beta-Peptides/metabolism , Animals , Humans , Mice , Mice, Transgenic , Peptide Fragments/metabolism , Purines/pharmacology , Receptors, Notch/metabolism , Structure-Activity RelationshipABSTRACT
The development of a novel series of piperazinyl pyrimidines as gamma-secretase modulators for potential use in the treatment of Alzheimer's disease is disclosed herein. Optimization of a screening hit provided a series of potent gamma-secretase modulators with >180-fold in vitro selectivity over inhibition of Notch cleavage.
Subject(s)
Amyloid Precursor Protein Secretases/metabolism , Piperazines/chemistry , Pyrimidines/chemistry , Amyloid Precursor Protein Secretases/antagonists & inhibitors , Amyloid beta-Peptides/antagonists & inhibitors , Amyloid beta-Peptides/metabolism , Amyloid beta-Peptides/physiology , Cell Line, Tumor , HeLa Cells , Humans , Peptide Fragments/antagonists & inhibitors , Peptide Fragments/metabolism , Piperazines/pharmacology , Pyrimidines/pharmacologyABSTRACT
In a previous study we demonstrated a requirement for activation of mTORC1 in the stimulation of eIF2Bepsilon mRNA translation in skeletal muscle in response to resistance exercise. Although that study established the necessity of mTORC1 activation, the experimental model used did not lend itself readily to address the question of whether or not mTORC1 activation was sufficient to produce the response. Therefore, the present study was designed to address the sufficiency of mTORC1 activation, using cultures of Rat2 fibroblasts in which mTORC1 signaling was repressed by serum/leucine-depletion and stimulated by repletion of leucine and/or IGF-1. Repletion with leucine and IGF-1 caused a shift of eIF2Bepsilon mRNA into actively translating polysomes and a stimulation of new eIF2Bepsilon protein synthesis, but had no effect on mRNAs encoding the other four eIF2B subunits. Stimulation of eIF2Bepsilon translation was reversed by pre-treatment with the mTORC1 inhibitor rapamycin. Exogenous overexpression of FLAG-Rheb, a proximal activator of mTORC1, also caused a re-distribution of eIF2Bepsilon mRNA into polysomes and a stimulation of eIF2Bepsilon protein synthesis. The stimulation of eIF2Bepsilon mRNA translation occurred in the absence of any effect on eIF2Bepsilon mRNA abundance. RNAi-mediated knockdown of eIF2Bepsilon resulted in reduced cellular proliferation, a result that phenocopied the known cytostatic effect of mTORC1 repression. Overall the results demonstrate that activation of mTORC1 is both necessary and sufficient to stimulate eIF2Bepsilon mRNA translation and that this response may represent a novel mechanism through which mTORC1 can affect mRNA translation initiation, rates of protein synthesis, and cellular growth/proliferation.
