Combined Influence of Gelatin Fibre Topography and Growth Factors on Cultured Dorsal Root Ganglia Neurons

Abstract

Nerve guidance channels facilitate nerve regeneration and represent an attractive alternative to nerve graft. Actually, nano- and microstructured biomaterials for nerve reconstruction have gained much attention, thanks to recent discoveries about topography effects on cell behavior and morphology. Electrospun fibres have been proposed as filler or structural component for nerve guidance channels, principally due to their similarity with extracellular matrices which facilitate nerve regeneration. Among several tested biomaterials, gelatin has been used to prepare fibres able to support Schwann cell migration and neurite outgrowth. In this work, the effects of gelatin fibre size on axon elongation and Schwann cell migration have been tested using dorsal root ganglia cultures. Moreover, we analyzed how fibres might affect the expression of specific neuronal subtype markers in sensory neuron cultures and how the combined effect of substrate and biological cues affects neurite growth and gene expression. Data show that fibre topography differentially affects both neurite outgrowth and gene expression and suggest that fibre size and topography associated to specific growth factor exposure might be used to select neuron subpopulations and favor the axonal growth of specific neurons. Anat Rec, 301:1668-1677, 2018. © 2018 Wiley Periodicals, Inc.

Biomaterials for Regenerative Medicine in Italy: Brief State of the Art of the Principal Research Centers

“…Beneficial effects were observed on motor neuron survival, Schwann cell proliferation and the sustained growth of regenerating peripheral nerve fibers [ 72 ]. Some of their recent studies for peripheral nerve regeneration have focused on different mixes of injectable gelatins (obtained from collagen thermal degradation) to support Schwann cell migration and growth [ 73 ], natural hydrogels as fillers in peripheral nerve conduit channels [ 74 ], and decellularized nerve allografts [ 75 ].…”

Cell-Cell and Cell-Matrix Interactions during Axons Guidance

“…Since early observation about the alignment and orientation of axons by "contact guidance," and the improving of axon elongation by aligned collagen fibrils [22,67], advance in micro-and nanofabrication of biocompatible fibrous substrates, with specific topography and orientation, has shown to improve neurite elongation and orientation, promoting nerve regeneration [68]. Fibers alignment and dimensions are important to improve axonal guidance and elongation, for example, the micrometer versus nanometer dimensions of poly(lactic-glycolic acid) PLGA fibers improve the alignment of neurites [69], and aligned versus nonaligned gelatin and chitosan fibers induce a higher formation of filopodia in Schwann cells, improving the orientation of axon projections along the fibers [70].…”

Introduction: Thematic Papers Issue on Peripheral Nerve Regeneration and Repair

“…The aim of the study presented by Gnavi et al, a collaborative team of different institutes of the University and Politecnico of Torino, was to investigate the applicability of gelatin fibers combined with hydrogel, as an adequate filler for nerve conduits. In the in vitro study, they found that fiber size and topography may affect both the amount of neurite outgrowth and the gene expression of neuronal subpopulations, favoring axonal regeneration from specific neuronal populations (Gnavi et al, , this issue).…”