Author ORCID Identifier
0009-0008-0772-9423
Date of Award
Fall 12-18-2024
Degree Type
Thesis
Degree Name
Master of Interdisciplinary Studies (MIS)
Department
Biomedical Sciences
First Advisor
Dr. Ping Song
Second Advisor
Dr. Chunying Li
Abstract
Background: Over the last decade, the prevalence, morbidity, and mortality of cardiovascular diseases (CVDs) have increased worldwide. Ferroptosis being an iron-dependent cell death has been recently recognized to be triggered by lipid peroxides buildup and is increasingly linked to the onset and progression of CVDs. Vascular smooth muscle cells (VSMCs), which are critical for the proper functioning of the vasculature are particularly susceptible to ferroptosis damage. Recent studies suggest that tryptophan metabolites may modulate ferroptosis in cancer cells, but their effects on VSMCs remain completely unexplored. Therefore, this study seeks to determine the effect of 3-hydroxyanthranilic acid (3-HAA), a key metabolite of the kynurenine pathway, on ferroptosis in VSMCs.
Methods: Ferroptosis was induced in primary human VSMCs using ferroptosis inducers, erastin and Ras- selective lethal 3 (RSL3). 3HAA, or other tryptophan metabolites, 3-hydroxykynurenine (3-HK), and Kynurenine (L-KYN) was administered to assess its effect. The C11-BODIPY581/591 dye was used to assess lipid peroxidation in the cultured VSMCs. Western blotting and reverse transcription polymerase chain reaction (RT-qPCR) were performed to evaluate the protein and gene expression levels of ferroptosis markers, including transferrin receptor 1 (TFR1), SLC7A11, glutathione peroxidase 4 (GPX4). The involvement of the nuclear factor erythroid 2-related factor 2 (NRF2) pathway in mediating protection was also assessed.
Results: RSL3 treatment in VSMCs resulted in significant lipid peroxidation and morphological changes, such as cellular deformation and cell shrinkage. Fluorescence analysis using the BODIPY581/591 C11 dye revealed a marked increase in fluorescence intensity, indicating elevated lipid peroxidation in ferroptosis-induced cells. Treatment with 3-HAA rescued the cells from ferroptosis by upregulating GPX4 and SLC7A11 expression levels at both transcriptional and protein levels, confirming its protective role. In contrast, neither 3-HK nor L-KYN mitigated RSL3-induced ferroptosis. The protective effect of 3-HAA may be linked to the activation of the NRF2 antioxidant pathway, while 3-HK and L-KYN had no significant effect on this pathway.
Conclusion: This study demonstrates that 3-HAA protects VSMCs from ferroptosis by reducing lipid peroxidation, which may be associated with NRF2 pathway activation. The findings suggest that 3-HAA shows promise as a potential therapeutic agent for mitigating ferroptosis-related vascular damage in CVDs, such as atherosclerosis and aortic aneurysm.
Recommended Citation
Dosunmu, Aminat Olamide, "Protective Effects of 3-Hydroxyanthranilic Acid Against Ferroptosis in Vascular Smooth Muscle Cells." Thesis, Georgia State University, 2024.
https://scholarworks.gsu.edu/biomedical_theses/14