Sagar, Kareena2020-07-072020-07-072020-06https://hdl.handle.net/1813/70160The peripheral nervous system’s ability to regenerate after injury declines with age, but the reason for why this occurs is unknown. With the goal to understand the role of age-associated transcriptional changes in the impairment of peripheral nerve injury, I conducted a differential gene expression experiment using RNA sequencing and functional recovery experiments with gait analysis and peak tetanic force measurements. In young mice, genes involved in cell proliferation and neurogenesis were upregulated compared to old mice. In contrast, in aged mice I observed upregulation of genes encoding proteinases and pro-inflammatory cytokines. Following a peripheral nerve injury, young animals and old animals expressed a similar ability to activate regenerative transcriptional programs. Gait analyses and measurements of muscle strength showed no significant difference nor any delay in the ability of old animals to recover from peripheral nerve injury. In summary, this study identified several markers of inflammatory and immune system pathways and pathways involved in nerve regeneration that differ in their expression between young and old mice. Understanding the role of these pathways in nerve regeneration may provide therapeutic targets to enhance regeneration in aging individuals.Biological sciences honors programperipheral nerve regeneration; aging; differential gene expression; macrophages; gait analysisdissertation or thesis