Phenotypic Screening of human iPSC-Derived Neurons identifies Thienopyridone as a Neuritogenic Small Molecule

Human induced pluripotent stem cell (iPSC)-derived neurons provide a platform for modeling a wide range of brain disorders. Among disease-relevant cellular phenotypes, impaired neurite outgrowth has emerged as a robust and quantifiable indicator that reflects core aspects of neurodevelopmental and neurodegenerative disease pathophysiology. In this study, we performed a high-throughput phenotypic chemical screen of over 21,000 small molecules to identify compounds that enhance neurite outgrowth in iPSC-derived cortical neurons.By iterative validation using disease-specific and control iPSC-derived neuronal lines, we identified three bioactive compounds that were sharing a common indazole scaffold. Two hit compounds were further validated in a human neural organoid model, where they proliferated neural stem cells by reproducing the neurite-promoting effect. Transcriptomic profiling revealed activation of signaling pathways associated with neurotrophic stimulation. These findings identified a novel scaffold for a neurogenic compound, suggesting the potential of this compound as a therapeutic strategy for brain disorders and for promoting neural regeneration.