Author ORCID Identifier

https://orcid.org/0000-0002-3703-0559

Year of Publication

2022

Degree Name

Master of Science (MS)

Document Type

Master's Thesis

College

Arts and Sciences

Department/School/Program

Biology

First Advisor

Dr. Ashley W. Seifert

Abstract

Regeneration is a wound repair process that terminates in the restoration of tissue function and structure. Fibroblasts play pivotal roles in regenerative and fibrotic wound repair. Reports of extensive regenerative ability in mammals have been historically rare, but more recently spiny mice (Acomys) have emerged as a bona fide model of complex tissue regeneration. Recent work has indicated that fibroblasts from regenerators (Acomys and Oryctolagus) are more resistant to reactive oxygen species (ROS)-induced senescence compared to non-regenerating species, suggesting the influence of intrinsic cellular states on the fate of wound repair. Determining the basal metabolic signature of fibroblasts in the wound microenvironment, which experiences drastic changes in pH, cytokine bursts, hypoxia, damage associated molecular patterns (DAMPs), ROS bursts, as well as an innate and adaptive immune response, is key to understanding the dichotomy in wound repair outcomes between regenerating and non-regenerating species. I made use of fibroblasts isolated from the ear pinna of sexually mature spiny mice (Acomys cahirinus) and laboratory mice (Mus musculus), since extensive tissue repair had been reported in the former and not in the latter. I hypothesized that the underlying metabolic signatures between the two species would differ significantly with respect to glycolytic flux: oxidative phosphorylation (OxPHOS) rate ratios, with Mus exhibiting higher OxPHOS flux and Acomys being comparably glycolytic. In this study we show that under basal conditions in vitro, fibroblasts from Acomys possess a glycolytic bias compared to fibroblasts from Mus. In response to chronic glucose starvation, Acomys fibroblasts show no significant changes in glycolytic or OxPHOS rates, whereas Mus fibroblasts respond with significant increases in glycolytic and OxPHOS rates under similar conditions. In a bid to determine if glutamine metabolism played a pivotal role in maintaining this metabolic state in Acomys, we observed that treatment with BPTES (a glutamine metabolism inhibitor) caused mostly insignificant reductions in OxPHOS and glycolytic flux rates in both species, while DMSO exposure caused Acomys fibroblasts to switch their metabolic signature in response to glucose starvation, to one identical to Mus.

Digital Object Identifier (DOI)

https://doi.org/10.13023/etd.2022.238

Funding Information

Funding for this study was partially provided by:

National Institutes of Health (NIH) grants R01 AR070313 (2017) and R21 DE028070 (2019)

to Ashley W. Seifert.

Funds were allocated to the author across the last two years. (2020-2022)

Available for download on Thursday, November 10, 2022

Included in

Cell Biology Commons

Share

COinS