title: Mercury Accumulation, Structural Damages, and Antioxidant and Immune Status Changes in the Gilthead Seabream (Sparus aurata L.) Exposed to Methylmercury.
abstract: In aquatic systems, mercury (Hg) is an environmental contaminant that causes acute and chronic damage to multiple organs. In fish, practically all of the organic Hg found is in the form of methylmercury (MeHg), which has been associated with animal and human health problems. This study evaluates the impact of waterborne-exposure to sublethal concentrations of MeHg (10 μg L(-1)) in gilthead seabream (Sparus aurata). Hg was seen to accumulate in liver and muscle, and histopathological damage to skin and liver was detected. Fish exposed to MeHg showed a decreased biological antioxidant potential and increased levels of the reactive oxygen molecules compared with the values found in control fish (nonexposed). Increased liver antioxidant enzyme activities (superoxide dismutase and catalase) were detected in 2 day-exposed fish with respect to the values of control fish. However, fish exposed to MeHg for 10 days showed liver antioxidant enzyme levels similar to those of the control fish but had increased hepato-somatic index and histopathological alterations in liver and skin. Serum complement levels were higher in fish exposed to MeHg for 30 days than in control fish. Moreover, head-kidney leukocyte activities increased, although only phagocytosis and peroxidase activities showed a significant increase after 10 and 30 days, respectively. The data show that 30 days of exposure to waterborne MeHg provokes more significant changes in fish than a short-term exposure of 2 or 10 days.
authors.affiliation: Fish Innate Immune System Group, Department of Cell Biology and Histology, Faculty of Biology, Campus Regional de Excelencia Internacional "Campus Mare Nostrum", University of Murcia, 30100, Murcia, Spain.
authors.forename: F A
authors.initials: FA
authors.lastname: Guardiola
authors.affiliation: Centro Oceanográfico de Murcia, Instituto Español de Oceanografía (IEO), Carretera de la Azohía s/n, Puerto de Mazarrón, 30860, Murcia, Spain.
authors.forename: E
authors.initials: E
authors.lastname: Chaves-Pozo
authors.affiliation: Fish Innate Immune System Group, Department of Cell Biology and Histology, Faculty of Biology, Campus Regional de Excelencia Internacional "Campus Mare Nostrum", University of Murcia, 30100, Murcia, Spain.
authors.forename: C
authors.initials: C
authors.lastname: Espinosa
authors.affiliation: Laboratory of Toxicology, Department of Sociosanitary Sciences, Campus Regional de Excelencia Internacional "Campus Mare Nostrum", University of Murcia, 30100, Murcia, Spain.
authors.forename: D
authors.initials: D
authors.lastname: Romero
authors.affiliation: Fish Innate Immune System Group, Department of Cell Biology and Histology, Faculty of Biology, Campus Regional de Excelencia Internacional "Campus Mare Nostrum", University of Murcia, 30100, Murcia, Spain.
authors.forename: J
authors.initials: J
authors.lastname: Meseguer
authors.affiliation: Fish Innate Immune System Group, Department of Cell Biology and Histology, Faculty of Biology, Campus Regional de Excelencia Internacional "Campus Mare Nostrum", University of Murcia, 30100, Murcia, Spain.
authors.forename: A
authors.initials: A
authors.lastname: Cuesta
authors.affiliation: Fish Innate Immune System Group, Department of Cell Biology and Histology, Faculty of Biology, Campus Regional de Excelencia Internacional "Campus Mare Nostrum", University of Murcia, 30100, Murcia, Spain. aesteban@um.es.
authors.forename: M A
authors.initials: MA
authors.lastname: Esteban
mesh_terms: D000818:Animals; D002374:Catalase / Q000378:metabolism; D004784:Environmental Monitoring; D008099:Liver / Q000378:metabolism / Q000648:ultrastructure; D008628:Mercury / Q000378:metabolism / Q000633:toxicity*; D008767:Methylmercury Compounds / Q000378:metabolism / Q000633:toxicity*; D021541:Sea Bream / Q000502:physiology*; D013482:Superoxide Dismutase / Q000378:metabolism
chemical_list: D008767:Methylmercury Compounds; D002374:Catalase; D013482:Superoxide Dismutase; D008628:Mercury