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

• Published in: PloS one Vol. 19; no. 9; p. e0304773
• Main Authors: Weiss, Samantha N., Legato, Joseph M., Liu, Yichuan, Vaccaro, Courtney N., Da Silva, Renata Pellegrino, Miskiel, Sandra, Gilbert, Grace V., Hakonarson, Hakon, Fuller, David A., Buono, Russell J.
• Format: Journal Article
• Language: English
• Published: United States Public Library of Science 04.09.2024; Public Library of Science (PLoS)
• Subjects: Analysis; Animals; Bioinformatics; Biology and Life Sciences; Care and treatment; Clinical outcomes; Composition; Degeneration; Diagnosis; Disease Models, Animal; Gene expression; Gene Expression Profiling; Gene Expression Regulation - drug effects; Gene fusion; Gene regulation; Gene sequencing; Genetic aspects; Injuries; Injury analysis; Injury prevention; Innervation; Laboratory animals; Male; Medical examination; Medicine and Health Sciences; Molecular modelling; Muscle, Skeletal - drug effects; Muscle, Skeletal - innervation; Muscle, Skeletal - metabolism; Muscles; Nerve Regeneration - drug effects; Nerve Regeneration - genetics; Nervous system; Neurodegeneration; Patient satisfaction; Peripheral nerve diseases; Peripheral Nerve Injuries - genetics; Peripheral nerves; Polyethylene glycol; Polyethylene Glycols - pharmacology; Rats; Rats, Inbred Lew; Recovery; Recovery of function; Research and analysis methods; Ribonucleic acid; RNA; RNA sequencing; Sciatic nerve; Sciatic Nerve - injuries; Sequence Analysis, RNA; Sutures; Trauma; United States
• ISSN: 1932-6203; 1932-6203
• DOI: 10.1371/journal.pone.0304773

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. Subjects were randomly assigned to receive either PEG treatment or standard repair at the time of neurorrhaphy. Samples of sciatic nerve distal to the injury and tibialis muscle at the site of innervation were harvested at 24 hours and 4 weeks postoperatively. Total RNA sequencing and subsequent bioinformatics analyses were used to identify significant differences in differentially expressed genes (DEGs) and their related biological pathways (p<0.05) in PEG-treated subjects compared to non-PEG controls. No significant DEGs were identified in PEG-treated sciatic nerve compared to controls after 24 hours, but 1,480 DEGs were identified in PEG-treated tibialis compared to controls. At 4 weeks, 918 DEGs were identified in PEG-treated sciatic nerve, whereas only 3 DEGs remained in PEG-treated tibialis compared to controls. DEGs in sciatic were mostly upregulated (79%) and enriched in pathways present during nervous system development and growth, whereas DEGs in muscle were mostly downregulated (77%) and related to inflammation and tissue repair. Our findings indicate that PEG application during primary neurorrhaphy leads to significant differential gene regulation in the neural and muscular environment that is associated with improved functional recovery in animals treated with PEG compared to sham non-PEG controls. A detailed understanding of key molecules underlying PEG function in recovery after peripheral nerve repair may facilitate amplification of PEG effects through systemic or focal treatments at the time of neurotmesis.