Project Summary One of the important signaling networks in embryonic development, regeneration, and homeostasis of tissue is the endogenous bioelectricity. It has been observed that electric fields can promote axonal regrowth in nerve injury and bioelectric stimuli can be crucial to induce regeneration in peripheral and central nervous systems. However, the transduction mechanisms that allow cells to convert bioelectric signals into gene regulatory networks and transmit them to recipient cells via exocytosis pathways has not been fully understood. The overarching goals of this MIRA application for the next five years will be to understand the effect of endogenous electric fields on exocytosis pathway through the small extracellular vesicles (EVs); and to use this knowledge in the future to establish a new EV-based therapeutic to restore function and repair of neurons in neurological disorders and injuries. To address the knowledge gaps, we aim to first electrically stimulate Schwann cells (SCs), the glial component of peripheral nervous system, by developing a biomimetic piezoelectric nanofiber networks to mimic the endogenous bioelectric stimuli. The proposed bioactive piezoelectric nanofibers will be advantageous over current technologies since they have high spatial resolution and high surface to volume ratio that can promote cells attachment and alignment. Also, the piezoelectric properties of fibers allow cells to self- induce electrical stimulation as a result of mechanobiology which can better mimic the endogenous mechanotransduction feedback loop between cellular networks in a three-dimensional (3D) microenvironment. We further plan to investigate the role of EVs secreted from electrically stimulated SCs, as cargos to transmit the bioelectric signals by means of RNAs and proteins to neurons and to study their functional role in promoting the axonal regeneration.