Eumelanin-Coated Aligned PLA Electrospun Microfibers to Guide SH-SY5YCells Spreading, Alignment, And Maturation

During the development of the nervous system, neurons sense and respond to topographical and biochemical cues found in the brain's native environment. Such niche-specific cues are pivotal for neural tissue formation and development and have been now widely exploited in neural tissue engineering to develop biologically-inspired scaffolds able to trigger a desired neuronal behavior. In particular, anisotropic aligned fibers, recapitulating the design of extending axonal tracts or aligned fibers found in the extracellular environment, have emerged as ideal candidates to guide cell alignment and elongation along the substrate main axis as well as promote neuronal differentiation. Among natural polymers used for coatings, melanins, including eumelanin, have been shown to possess antioxidant, anti-inflammatory, immunomodulatory, and photo-protective properties. Here, aligned poly(lactic acid) (PLA) fibers are fabricated via electrospinning and then coated with eumelanin via spin coating. Eumelanin-coated aligned PLA fibers are highly biocompatible and greatly influenced the adhesion, morphology, and spreading of SH-SY5Y neuroblastoma cells. Furthermore, the eumelanin coating is crucial in promoting cell alignment at the cell-material interface and SH-SY5Y cell maturation towards a more mature neuronal phenotype.