An analysis of differential gene expression in peripheral nerve and muscle utilizing RNA sequencing after polyethylene glycol nerve fusion in a rat sciatic nerve injury model
Samantha N. Weiss, Joseph M. Legato, Yichuan Liu, Courtney N. Vaccaro, Renata Pellegrino Da Silva, Sandra Miskiel, Grace V. Gilbert, Hakon Hakonarson, David A. Fuller, Russell J. Buono
Abstract
Application of polyethylene glycol (PEG) to a peripheral nerve injury at the time of primary neurorrhaphy is thought to prevent Wallerian degeneration via direct axolemma fusion. The molecular mechanisms of nerve fusion and recovery are unclear. Our study tested the hypothesis that PEG alters gene expression in neural and muscular environments as part of its restorative properties. Lewis rats underwent unilateral sciatic nerve transection with immediate primary repair.
Introduction
Peripheral nerve injuries (PNIs) result in a continuum of symptoms ranging from mild discomfort to dramatic motor or sensory disturbances [1]. The majority of PNIs occur in the setting of trauma, specifically from motor vehicle accidents (46.4%), penetrating trauma (23.9%), and falls (10.9%) [2]. It has been posited that iatrogenic nerve injuries account for an additional 17.4% of PNIs [3]. Furthermore, studies have shown that up to 1.6% of all patients suffering traumatic upper- or lower-limb injuries were complicated by permanent, life-altering nervous system deficits [4].
Materials and method
Ethics statement
This study was carried out in strict accordance with the recommendations in the Guide for the Care and Use of Laboratory Animals of the National Institutes of Health. The protocol was approved by the Institutional Animal Care and Use Committee of Cooper University Hospital (IACUC Protocol Number: 2019–004).
Results
Our results demonstrate an inverse relationship in differential gene expression among sciatic nerve and tibialis anterior muscle at 24 hours and 4 weeks post-repair as shown in Table 1.
Discussion
The use of PEG in repair of transected peripheral nerves is a promising development for the treatment of high-grade PNIs. A recent systematic review highlighted sixteen animal studies that all document superiority in outcomes following treatment with PEG via histological, electrophysiological, and/or behavioral measures [35]. However, the molecular basis facilitating these improved outcomes associated with intraoperative PEG fusion during primary neurorrhaphy is not clearly understood. To our knowledge, this is the first study utilizing RNA sequencing to investigate differential gene expression following PEG-augmented primary neurorrhaphy in both nerve and muscle tissues in a rat sciatic nerve transection model.
Conclusion
Our data suggest that PEG-induced differential gene regulation in both distal nerve and muscle contributes to the inhibition of Wallerian degeneration and functional preservation in this rat sciatic nerve transection model. DEGs related to promoter function and mRNA processing could be viable targets for therapeutic intervention in the future. These new data document pathways that are differentially regulated in PEG compared to non-PEG treated nerve and muscle and open a window on the molecular landscape that could be used to develop specific treatment strategies for PNIs by augmenting and improving on PEGs protective effects.
Citation: Weiss SN, Legato JM, Liu Y, Vaccaro CN, Da Silva RP, Miskiel S, et al. (2024) An analysis of differential gene expression in peripheral nerve and muscle utilizing RNA sequencing after polyethylene glycol nerve fusion in a rat sciatic nerve injury model. PLoS ONE 19(9): e0304773. https://doi.org/10.1371/journal.pone.0304773
Editor: Jianxun Ding, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, CHINA
Received: December 15, 2023; Accepted: May 19, 2024; Published: September 4, 2024
Copyright: © 2024 Weiss et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.
Data Availability: Full lists of differentially expressed genes obtained from the RNA sequencing DESeq2 analysis are available as supplementary tables 1–4. All pathway and gene informatics was performed on public available web based applications using gene lists as input as described in the methods section. All significant output from these analyses are listed in tabular form in the manuscript except for two tables where complete results are found in supplementary tables 5–6.
Funding: Supported by grant from the Rowan University Camden Health Research Initiative 16000-85003-13 to DAF and RJB. The sponsors played no role in the design, data collection, analysis, decision to publish or preparation of the manuscript. https://rdw.rowan.edu/camden_health_research_initiative/.
Competing interests: The authors have declared that no competing interests exist.
