Disease outbreaks, skin lesions, mortality events, and reproductive abnormalities have been observed in wild populations of centrarchids. The presence of estrogenic endocrine disrupting compounds (EEDCs) has been implicated as a potential causal factor for these effects. The effects of prior EEDC exposure on immune response were examined in juvenile largemouth bass (Micropterus salmoides) exposed to a potent synthetic estrogen (17α-ethinylestradiol, EE2) at a low (EE2Low, 0.87 ng/L) or high (EE2High, 9.08 ng/L) dose for 4 weeks, followed by transfer to clean water and injection with an LD40 dose of the Gram-negative bacteria Edwardsiella piscicida. Unexpectedly, this prior exposure to EE2High significantly increased survivorship at 10 d post-infection compared to solvent control or EE2Low-exposed, infected fish. Both prior exposure and infection with E. piscicida led to significantly reduced hepatic glycogen levels, indicating a stress response resulting in depletion of energy stores. Additionally, pathway analysis for liver and spleen indicated differentially expressed genes associated with immunometabolic processes in the mock-injected EE2High treatment that could underlie the observed protective effect and metabolic shift in EE2High-infected fish. Our results demonstrate that exposure to a model EEDC alters metabolism and immune function in a fish species that is ecologically and economically important in North America.
|Title||Exposure to 17α-ethinylestradiol results in differential susceptibility of largemouth bass (Micropterus salmoides) to bacterial infection|
|Authors||Jessica Kristin Leet, Justin Greer, Catherine A. Richter, Luke R. Iwanowicz, Edward Spinard, Jacquelyn McDonald, Carla M. Conway, Robert W. Gale, Donald E. Tillitt, John Hansen|
|Publication Subtype||Journal Article|
|Series Title||Environmental Science and Technology|
|Record Source||USGS Publications Warehouse|
|USGS Organization||Columbia Environmental Research Center; Leetown Science Center; Western Fisheries Research Center|