DOI
https://doi.org/10.25772/7g8r-fx10
Defense Date
2026
Document Type
Thesis
Degree Name
Master of Science
Department
Microbiology & Immunology
First Advisor
Dr. Rebecca Martin
Abstract
Atopic Dermatitis (AD) is an inflammatory skin condition that affects 15-20% of children and around 10% of adults, occurring as a result of genetic, environmental, or microbial factors. As the role of hypoxia-inducible factor-1alpha (HIF-1α) is known to be a key regulator of epidermal barrier function, it remains unclear clinically, how stabilizing its pathway actually functions to modulate the complex cellular environment within AD. Characterizing the downstream effects is necessary to determine if targeting these oxygen-sensing and metabolic pathways could serve as a viable therapeutic option for chronic inflammatory skin conditions, like AD. The aims of this study were first, to identify and characterize gene expression downstream of HIF-1α in AD, and second, to examine HIF-1α changes in various cell types in AD tissue to assist with cellular characterization. This was done using ear tissue samples from AD mice, utilized for analysis. Regarding the first aim, reverse transcription-quantitative PCR (RT-qPCR) was performed to analyze downstream gene expression of the twenty highest abundance genes from RNA-seq that was done previously for mice induced with AD, pertaining to one vehicle and two drug-treated groups. Regarding the second aim, immunohistochemistry (IHC) was conducted on the AD mouse ear tissue samples to evaluate possible HIF-1α changes across different cell types, for the same experimental groups. The drugs used in this project were Roxadustat, a hypoxia-inducible factor prolyl hydroxylase (HIF-PH) inhibitor, and CB-839 or Telaglenastat, an oral reversible inhibitor that inhibits glutaminase 1 and disrupts glutaminolysis. The RT-qPCR analysis identified changes in genes downstream of HIF-1α in the AD model, specifically displaying trends of almost all of the keratin family and other related genes to be upregulated in Roxadustat and CB839 treatment groups compared to vehicle but specifically Roxadustat, indicating that the restoration from the drug facilitates expression of genes whose functions were disrupted as a result of AD, due to the epithelium and barrier dysfunction that is caused by AD. Additionally, IHC analysis revealed that Roxadustat contained an increased percentage of positive stain for HIF-1α as compared to vehicle and CB839, which was supported by the concept of the mechanistic action of Rox being a HIF-1α stabilizer. Collectively from the qPCR and IHC findings, it can be concluded that the drugs do not have as direct of an effect on keratinocyte or epithelial associated genes or the epithelium in general. Drug upregulates HIF-1α in dermal cells and infiltrating cells, possibly immune cells, as seen by the expression in the dermal layer rather than within the epidermis itself. Therefore, there is more of a direct immune effect in AD from the drugs as opposed to an epithelial effect.
Rights
© The Author
Is Part Of
VCU University Archives
Is Part Of
VCU Theses and Dissertations
Date of Submission
8-6-2026