Neuradapt: Structural Optimization and Transcriptomic Analysis

A newly developed “branched tail” oxyquinoline, neuradapt, and its variants are an order of magnitude more effective HIF prolyl hydroxylase (HIF PHD) inhibitors than roxadustat and vadadustat in HIF1 ODD-luc reporter assay. Structure-activity relationships and computer modeling for the oxyquinoline inhibitors point to the plausible engagement of the pyridine ring nitrogen in interaction with Asp254 residue inside the active site pocket. 2-Methyl-substituted variant of neuradapt was found active in the reporter assay and equally effective in pretreatment paradigm of oxygen glucose deprivation model in neuroblastoma cell line. Microtranscriptomic analysis of the signaling pathways induced by two neuradapt variants in comparison with roxadustat and dimethyl oxalyl glycine shows extreme potency of novel inhibitors working at low micromolar concentrations. Neuradapt and its 2-methyl analog exert the same activation of glycolytic and other HIF-triggered pathways, but result in distinct effects on pathways linked to alternative substrates of HIF PHD1/3 such as p53, NfkB, ATF4, etc. This finding can be interpreted as the specificity of the 2-methyl-substituted variant for HIF PHD2. Total RNA was prepared from SH-SY5Y cells treated with 2 variants of neuradapt (compounds 5704-0720 and 4896-3249), roxadustat (FG-4592) and dimethyl oxalylglycine (DMOG) as well as from control SH-SY5Y cells and the cells after hypoxia.