Pharmacological Manipulation of Nested Oscillations in Human iPSC-Derived 2D Neuronal Networks

Neural networks, formed by synchronized oscillatory bursts of activity across large populations of neurons, are fundamental to human cognition and behavior, and disrupted in neurodevelopmental disorders. Yet, mechanisms driving the emergence of these rhythms, known as oscillogenesis, are not well understood, particularly in the human brain. Using multi-electrode arrays, we investigated oscillogenesis in 2D human induced pluripotent stem cell (hiPSC) cultures at different developmental stages, and under pharmacological challenges, in two models: 1) iCell GlutaNeurons (iGluta) and 2) Neurogenin-2 patterned induced neurons (NGN2-piNs). iGluta cultures exhibited nested oscillations that were reduced by GABAA receptor blockade and emerged earlier when the proportion of GABAergic neurons was increased. Furthermore, pharmacological manipulations of voltage-gated potassium (Kv) channels and cholinergic receptors modulated the pattern of nested oscillations, demonstrating the assay’s potential for drug screening and modeling network dysfunction. In contrast, NGN2-piNs exhibited only rudimentary nested oscillations that were not affected by GABAA receptor blockade, despite the presence of GABAergic neurons, and showed distinct responses to Kv channel blockade. These results reveal the capacity of these 2D cultures to model oscillogenesis, and underscore the need for their continued refinement, paving the way for linking systems-level neural networks to human cognition and disease. Study of gene expression in iCell GlutaNeurons (iGluta), FujiFilm Cellular Dynamics Inc. after 3 weeks of culture for determining cellular composition of the culture and expression of relevant receptors and channels