Impacts of perfluorooctanoic acid on porcine oocyte health and competence

The oocyte is the female gamete and develops within ovarian follicles and has intimate connection with the ovary, the ovarian blood supply, and the follicular fluid of antral follicles. Per- and polyfluoroalkylated substances are environmental toxicants that have been detected in the follicular fluid of women and animals, and which inflict negative effects to oocytes and somatic cells. Perfluorooctanoic acid (PFOA) is a PFAS that is of rising concern to human and animal health which is detected both in Iowa drinking water and human biological samples. PFOA is known to interact with albumin, a protein constituting over 50% of the protein fraction of follicular fluid. Limited reports exist to describe the effects of PFOA on oocyte health biomarkers at realistic contamination levels, and this work is the first to describe them in conjunction with albumin levels observed in vivo. Biomarkers of interest were oocyte meiotic stage and abundances of superoxide dismutase (SOD1), apoptosis inducing factor (AIF), and BCL 2 associated X protein (BAX). We hypothesized that oxidative stress and apoptotic pathways would be affected by PFOA during the meiotic maturation period, and that co-exposure with albumin would mitigate these effects. To test this central hypothesis, porcine oocytes were exposed to increasing concentrations of PFOA, albumin, or PFOA and albumin in maturation media for 41h. Total abundance of SOD1, AIF, and BAX was analyzed using immunofluorescence and maturation was assessed by the extrusion of a polar body. Our data demonstrates that PFOA impacts the abundance of SOD1, AIF, and BAX, and addition of 40 mg/mL albumin decreases abundances of these proteins while co-exposure affects protein expression differently than PFOA alone. Interestingly, pro-apoptotic proteins AIF and BAX were observed to localize in and around the polar bodies of all oocytes, regardless of treatment. Taken together, these results further contribute to scientific understanding of how PFOA impacts the function and success of the female reproductive system. The impacts of PFOA at levels congruent with observed contamination levels in Iowa are important to drive realistic regulatory standards.

Name thesis:degree_name

Master of Science

Level thesis:degree_level

thesis

Discipline thesis:degree_discipline

Physiology

Grantor

Iowa State University - Thesis & Dissertation

Year dc:date.issued

2026

Author dc:creator

• Grote, Caleigh, Elisabeth

Advisor dc:contributor.advisor

• Keating, Aileen, F.

• Animal science

Language dc:language.iso

en_US

Repository record dc:identifier.uri

https://dr.lib.iastate.edu/handle/20.500.12876/106709

OAI identifier oai:identifier

oai:dr.lib.iastate.edu:20.500.12876/106709