PVA-Based Scaffolds for Controlled Release of Neuroprotective Compounds

Abstract

To restore function lost by damage to the nerve fibers, nerve regeneration must take place. Poor clinical outcomes are still observed for many autografting surgeries, stem cell therapies, and growth factor treatments. Biomaterials-based tissue engineering approaches to nerve repair utilize nerve guides. These nerve guides can be made of a variety of materials, using various fabrication processes and design concepts. The use of these nerve guides in conjunction with neurotrophic factors, gene therapies, cell transplants, and extracellular matrix proteins has shown improved experimental results for promoting nerve regeneration. Here, contact drawn poly(vinyl alcohol) fibers were cross-linked with glyoxal, to increase resistance to dissolution and hydrolytic degradation in an aqueous environment for application as a component of a nerve guide. Quercetin (an anti-inflammatory plant flavonoid) was loaded into fibers in a dose-dependent manner prior to contact drawing and reached a maximum cumulative release of 56 ± 6%. Fibers were characterized via IR spectroscopy. Glyoxal cross-linking and quercetin loading effects on fiber formation behavior and fiber diameters were investigated. Initial cytotoxicity screening against PC12Adh cells indicated novel PVA fiber formulations were not cytotoxic. The contact-drawn, glyoxal cross-linked, quercetin-loaded PVA fibers demonstrated potential for release of quercetin – a known neuroprotectant. Incorporation of these PVA fibers into a nerve guide may have potential to alleviate scar tissue formation and fibrosis following surgical intervention, improving outcomes for patients suffering from nerve damage.