Electrophysiological assessment of a peptide amphiphile nanofiber nerve graft for facial nerve repair

Jacqueline J. Greene*, Mark T. McClendon, Nicholas Stephanopoulos, Zaida Álvarez, Samuel I. Stupp, Claus Peter Richter

*Corresponding author for this work

Research output: Contribution to journalArticlepeer-review

20 Scopus citations

Abstract

Facial nerve injury can cause severe long-term physical and psychological morbidity. There are limited repair options for an acutely transected facial nerve not amenable to primary neurorrhaphy. We hypothesize that a peptide amphiphile nanofiber neurograft may provide the nanostructure necessary to guide organized neural regeneration. Five experimental groups were compared, animals with (1) an intact nerve, (2) following resection of a nerve segment, and following resection and immediate repair with either a (3) autograft (using the resected nerve segment), (4) neurograft, or (5) empty conduit. The buccal branch of the rat facial nerve was directly stimulated with charge balanced biphasic electrical current pulses at different current amplitudes whereas nerve compound action potentials (nCAPs) and electromygraphic responses were recorded. After 8 weeks, the proximal buccal branch was surgically reexposed and electrically evoked nCAPs were recorded for groups 1–5. As expected, the intact nerves required significantly lower current amplitudes to evoke an nCAP than those repaired with the neurograft and autograft nerves. For other electrophysiologic parameters such as latency and maximum nCAP, there was no significant difference between the intact, autograft, and neurograft groups. The resected group had variable responses to electrical stimulation, and the empty tube group was electrically silent. Immunohistochemical analysis and transmission electron microscopy confirmed myelinated neural regeneration. This study demonstrates that the neuroregenerative capability of peptide amphiphile nanofiber neurografts is similar to the current clinical gold standard method of repair and holds potential as an off-the-shelf solution for facial reanimation and potentially peripheral nerve repair.

Original languageEnglish (US)
Pages (from-to)1389-1401
Number of pages13
JournalJournal of Tissue Engineering and Regenerative Medicine
Volume12
Issue number6
DOIs
StatePublished - Jun 2018

Funding

The authors are especially grateful for the technical support and expertise of Lennell Reynolds (Northwestern University Center for Advanced Microscopy generously supported by NCI CCSG P30 CA060553 awarded to the Robert H Lurie Comprehensive Cancer Center), Dr Lin Li (Mouse Histology and Phenotyping Laboratory, Northwestern University), and Hunter Young (laboratory manager, Richter lab, Northwestern University). Research reported in this publication was supported, in part, by the American Academy of Facial Plastic and Reconstructive Surgery Foundation Leslie Bernstein Grant, and the National Institutes of Health's National Center for Advancing Translational Sciences, Grant Number UL1TR000150, as administered by the Northwestern University Clinical and Translational Sciences Institute (NUCATS) pilot grant program. S. I. S. research was supported by the Northwestern University Center for Regenerative Nanomedicine through a CRN Catalyst Award. Z. A. has received postdoctoral support from Beatriu de Pinós Fellowship under award # 2014 BP‐A 00007 (Agència de Gestió d'Ajust Universitaris i de Recerca, AGAUR) and from Paralyzed Veterans of America (PVA) Research Foundation under award # PVA17_RF_0008. N. S. was supported by an NIH Ruth L. Kirschstein NRSA postdoctoral fellowship under award # 1F32NS077728‐01A1. The content is solely the responsibility of the authors and does not necessarily represent the official views of the National Institutes of Health. Beatriu de Pinós Fellowship 2014 (Agència de Gestió d'Ajust Universitaris i de Recerca, AGAUR), Grant/Award Number: BP‐A 00007; Northwestern University Clinical and Translational Sciences Institute (NUCATS); North-western University Center for Regenerative Nanomedicine through a CRN Catalyst Award; Paralyzed Veterans of America (PVA) Research Foundation, Grant/Award Number: PVA17_RF_0008; Agència de Gestió d'Ajust Universitaris i de Recerca, AGAUR, Grant/ Award Number: BP‐A 00007; National Institutes of Health's National Center for Advancing Translational Sciences, Grant/Award Number: UL1TR000150; American Academy of Facial Plastic and Reconstructive Surgery Foundation, Grant/Award Number: Leslie Bernstein CORE grant; NIH Ruth L. Kirschstein NRSA, Grant/Award Number: 1F32NS077728‐01A1

Keywords

  • electrophysiology
  • facial nerve repair
  • nanofiber neurograft
  • neural regeneration

ASJC Scopus subject areas

  • Biomedical Engineering
  • Medicine (miscellaneous)
  • Biomaterials

Fingerprint

Dive into the research topics of 'Electrophysiological assessment of a peptide amphiphile nanofiber nerve graft for facial nerve repair'. Together they form a unique fingerprint.

Cite this