Bifunctional peptide-conjugated vertically aligned tubular nanofibrous conduits for enhanced vascularization and...

Nerve Guidance Conduits (NGCs) are crucial for reducing trauma during nerve repair, directing axonal growth, and preventing scar tissue formation. In this study, tubular functional NGCs were developed based on vertically aligned electrospun poly(lactic-co-glycolic acid) (PLGA) nanofibers (vNGC). They were functionalized by conjugating them with bioactive mimetic peptides: a laminin-derived peptide (LD-BP) to promote vascularization, and nerve growth factor (NGF-BP) and brain-derived neurotrophic factor (BDNF-BP) mimetic peptides to support neural differentiation. The vascular differentiation of HUVECs in response to LD-BP, and the neuronal differentiation of PC12 cells in response to NGF-BP and BDNF-BP, were assessed. The results demonstrated that this approach enabled the fabrication of tubular vNGCs with various diameters, and that vertically aligned PLGA nanofibers significantly improved their structural integrity. Furthermore, BP-conjugated vNGCs outperformed non-conjugated control groups in promoting both vascular and neural differentiation. Importantly, peptide conjugation did not induce cytotoxicity or significantly alter the biodegradability of the vNGCs, supporting their suitability for biomedical applications. Finally, bifunctional vNGCs (BiF-vNGCs), conjugated with LD-BP, NGF-BP, and BDNF-BP, were tested in a rat model of sciatic nerve injury. The BiF-vNGCs showed superior performance compared to unmodified vNGC, Control and s-Control groups, effectively promoting vascularization and neural regeneration in vivo, offering a viable alternative to conventional nerve regeneration methods.