Aquaculture 2022

February 28 - March 4, 2022

San Diego, California

CYTOTOXIC RESPONSES TO THE PERFLUORINATED XENOBIOTIC, GENX OF ATP-BINDING CASSETTE PROTEIN AND CELLULAR ACTIVITIES IN Crassostrea virginica HEMOCYTES

Uma Volety*, Ai Ning Loh, Sasha Giametti, Aswani Volety, Nelly LeGoic, and Philippe Soudant

 

North Carolina School of Science and Math

1219 Broad St, Durham, NC 27705

Email: Volety22u@ncssm.edu

 



GenX is a perfluorinated compound that has been contaminating the Cape Fear River, NC for over 20 years. When organisms are exposed to GenX, it can enter their cells and cause toxicity. ABC proteins are responsible for removing xenobiotics like GenX from cells. However, when these proteins are inhibited, cellular toxicity increases. This project tested the hypotheses that: 1) GenX will inhibit ABC transporters thus increasing mitochondrial membrane potential, cytotoxicity and hypoxia and 2) incubation of hemolymph at a higher temperature to mimic climate change will cause increased inhibition of ABC transporters, and will cause increased mitochondrial membrane potential, cytotoxicity, and hypoxia. Hemolymph from wild adult oysters was exposed to filtered seawater, a protein inhibitor, Reversine, and two concentrations of the xenobiotic, GenX (1.5µM and 15µM). Samples were incubated in 5 replicates at 21°C, and at 30°C to mimic global climate change. The hemolymph was then exposed to various dyes to determine mitochondrial membrane potential, cytotoxicity, hypoxia, and cell mortality. Samples were analyzed using flowcytometry. Though not statistically significant, mitochondrial membrane potential increased in both GenX treatments compared to the control. When compared with the control, cytotoxicity increased in both GenX treatments. Hypoxia also increased in both GenX treatments, indicating that GenX is inhibiting the function of ABC proteins. While no effects of GenX on hemocyte viability were observed, hemocyte mortality after incubation at 30°C was higher than at 21°C. Cytotoxicity and mitochondrial membrane potential both decreased after incubation temperature was raised while hypoxia increased.