Discipline: Biological Sciences
Subcategory: Cell and Molecular Biology
Session: 1
Brooklyn B. Cunningham - Jackson State University
Co-Author(s): Danforth A. Newton, Demetri D. Spyropoulos and John E. Baatz, Medical University of South Carolina
Approximately 1.9 million gallons of the dispersant COREXIT EC9500A were used to disperse crude oil during the 2010 Deepwater Horizon oil spill. A significant amount of this dispersant was delivered through the air, although potential effects on human respiratory system were not known. Our previous studies have indicated that the main component of COREXIT, dioctylsodium sulfosuccinate (DOSS), exerts numerous effects on metabolic activity, subcellular protein localization and mitochondrial function in liver cells (1, 2). Our hypothesis is DOSS will affect expression of several regulators of metabolism in type II alveolar epithelial (ATII) cells. The murine ATII-like cell-line, MLE-15, was used for these experiments. Cultured cells were exposed for 18 hours to numerous DOSS concentrations up to 100 μg/ml. RNA and protein were extracted for analyses from each dosage. qPCR and western blotting were used to measure gene expression for several metabolic regulators and ATII phenotypic markers. DOSS concentrations above 50 μg/ml visibly affected cell growth/morphology and were discontinued. Exposures of MLE to 1 or 10 μg/ml DOSS resulted in no change in measured gene expression for any gene analyzed. At 25-50 μg/ml exposure, DOSS appeared to significantly reduce surfactant protein C and PPARα RNA expression. Higher concentrations of DOSS also appeared to increase phosphorylation of AMPK. The expression of PPARα and post-translational modification of AMPK, both master regulators of lipid metabolism, appeared to be affected by increasing exposure to DOSS in ATII cells. However, we did not see many dramatic changes in the expression of other genes measured. Still, there are other changes in the cells exposed to DOSS that remain to be analyzed, including energetic shifts, protein localization, effects on metabolic pathways, apoptosis induction, and stress signaling.
Funder Acknowledgement(s): I thank Stephanie Guion-Brown, Director of Summer Programs, and Dr. Cynthia F. Wright, Associate Dean for Admissions and Career Development, for their help in the research. This study was funded by the Summer Undergraduate Research Program, Medical University of South Carolina, Charleston, SC.
Faculty Advisor: Danforth Newton, newtond@musc.edu
Role: My part this research involved culturing mouse lung cells, MLE-15, while comparing them to various exposed and unexposed concentrations of dioctylsodium sulfosuccinate, DOSS. I studied and observed this cell-line everyday by keeping them alive, making sure they did not overpopulate the 6-well plate, and also diluting and counting the cells under a microscope. I extracted mRNA and protein from the DNA samples provided in order to conduct a qPCR and start western blotting.