Self-assembling scaffolds epigenetically reactivate and electroactively guide neuronal regeneration to restore central neural circuits

Abstract

Abstract Central nervous system (CNS) injury is a leading cause of death and long-term disability worldwide. Neurological deficits reflect disruption of central neural circuits. A major barrier to circuit repair is the intrinsically low regenerative potential of adult CNS neurons—linked in part to failure of injury-induced nuclear export of class IIa histone deacetylases (notably HDAC5)—together with a hostile post-injury microenvironment. Here we present a multifunctional nanosystem, encapsulating the class IIa HDAC4/5-selective inhibitor LMK-235 and featuring an electroactive polyaniline coating with asymmetrically distributed 5-hydroxytryptamine moieties. Upon reaching the lesion, our nanosystem assembles into large-pore scaffolds that (i) inhibit the activity of nuclear-retained class IIa HDACs in neurons and thereby reactivate intrinsic regenerative programs, (ii) regulate microglial activation to mitigate neuroinflammation, and (iii) provide an electroactive interface promoting activity-dependent synaptic reconnection. This multi-pronged approach illustrates an integrated platform with translational potential for CNS disorders in which circuit disconnection constrains recovery.