Altered resting-state functional connectivity in hiPSC-derived neuronal networks from schizophrenia patients

Abstract

ABSTRACTSchizophrenia (SZ) is a complex mental disease thought to arise from abnormal neurodevelopment, characterized by an altered reality perception and widely associated with brain connectivity anomalies. Previous work has shown disrupted resting-state brain functional connectivity (FC) in SZ patients. We used Human Induced Pluripotent Stem Cells (hiPSC)-derived neuronal cultures to study SZ’s neural communicational dynamics during early development. We conducted gene and protein expression profiling, calcium imaging and mathematical modeling to evaluate FC. Along the neurodifferentiation process, SZ networks displayed altered expression of genes related to synaptic function, cell migration and cytoskeleton organization, suggesting alterations in excitatory/inhibitory balance. Resting-state FC in neuronal networks derived from healthy controls (HC) and SZ patients emerged as a dynamic phenomenon exhibiting “hub-states”, which are connectivity configurations reoccurring in time. Compared to HC, SZ networks were less thorough in exploring different FC configurations, changed configurations less often, presented a reduced repertoire of hub-states and spent longer uninterrupted time intervals in this less diverse universe of hubs. Our observations at a single cell resolution may reflect intrinsic dynamical principles ruling brain activity at rest and highlight the relevance of identifying multiscale connectivity properties between functional brain units. We propose that FC alterations in SZ patients are a consequence of an abnormal early development of synaptic communication dynamics, compromising network’s ability for rapid and efficient reorganization of neuronal activity patterns. Remarkably, these findings mirror resting-state brain FC in SZ patients, laying the groundwork for future studies among such different spatiotemporal domains, as are brains and neurons, in both health and disease.