Design and characterisation of PHBV-magnesium oleate directional nanofibers for neurosupport

Biomed Mater. 2019 Oct 17;14(6):065015. doi: 10.1088/1748-605X/ab453c.

Abstract

The focus of significance in neuronal repair strategies is the design of scaffold systems capable of promoting neuronal regeneration and directional guidance via provision of a biomimetic environment resemblance of native neural tissue. The purpose of this study was to synthesize triple-cue electrospun aligned nanofibrous films (physical cue) of poly(3-hyroxybutyric acid-co-3-hydroxyvaleric acid) (PHBV) blended with magnesium-oleate (MgOl) (chemical cue) and N-acetyl-L-cysteine (NAC) (therapeutic cue) with potential incorporation into hollow nerve guidance conduits for an enhanced regenerative strategy. A Box-Behnken experimental design of 15 formulations, were analysed for crystallinity, textural properties and in vitro water-uptake, erosion, NAC-release and PC12 cell viability. Nucleating effects of MgOl provided tuning of PHBV electrospinning-induced crystallinity and mechanical properties. Tensile strengths and deformation moduli of ±12 MPa and ±7 MP, respectively, were attainable, thereby matching native nerve mechanics. Crystallinity changes ascribed differing release kinetics to NAC over 30 d: diffusion-based (42%-58% crystallinity with 33%-47% fractional release) and polymer-relaxational (59%-65% crystallinity with 60%-82% fractional release). The synergistic activity of MgOl and NAC increased PC12 proliferation by 32.6% compared to the control. MgOl produced dual actions as non-toxic plasticiser and PC12 cell proliferation-promoter via nucleation and neurotrophic-like effects, respectively. Controlled release of NAC imparted neuro-protectant effects on PC12 cells and promoted neurite extension, thus, making electrospun PHBV-MgOl nanofibrous films a versatile and promising approach for axonal guidance in peripheral nerve repair strategies.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Acetylcysteine / chemistry
  • Animals
  • Axons / metabolism
  • Biocompatible Materials / chemistry
  • Biomimetics*
  • Cell Proliferation
  • Magnesium / chemistry*
  • Nanofibers / chemistry
  • Nerve Regeneration / drug effects
  • Nerve Tissue
  • Neurons / cytology
  • Oleic Acid / chemistry*
  • PC12 Cells
  • Polyesters / chemistry*
  • Rats
  • Regenerative Medicine / methods*
  • Tensile Strength
  • Tissue Engineering
  • Tissue Scaffolds / chemistry
  • Water / chemistry

Substances

  • Biocompatible Materials
  • Polyesters
  • poly(3-hydroxybutyrate)-co-(3-hydroxyvalerate)
  • Water
  • Oleic Acid
  • Magnesium
  • Acetylcysteine