title: Impairment of mitochondrial energy metabolism of two marine fish by in vitro mercuric chloride exposure.
abstract: The goal of this work was to understand the extent of mercury toxic effects in liver metabolism under an episode of acute contamination. Hence, the effects of in vitro mercuric chloride in liver mitochondria were assessed in two commercial marine fish: Senegalese sole (Solea senegalensis) and gilthead seabream (Sparus aurata). Liver mitochondria were exposed to 0.2mgL(-1) of mercury, the average concentration found in fish inhabiting contaminated areas. Mercuric chloride depressed mitochondrial respiration state 3 and the maximal oxygen consumption in the presence of FCCP indicating inhibitory effects on the oxidative phosphorylation and on the electron transport chain, respectively. The inhibition of F1Fo-ATPase and succinate-dehydrogenase activities also corroborated the ability of mercury to inhibit ADP phosphorylation and the electron transport chain. This study brings new understanding on the mercury levels able to impair fish mitochondrial function, reinforcing the need for further assessing bioenergetics as a proxy for fish health status.
authors.affiliation: CESAM, Department of Chemistry, University of Aveiro, Campus de Santiago, 8005-135 Aveiro, Portugal. Electronic address: cmieiro@ua.pt.
authors.forename: C L
authors.initials: CL
authors.lastname: Mieiro
authors.affiliation: CFE, Department of Life Sciences, University of Coimbra, Apartado 3046, 3001-401 Coimbra, Portugal.
authors.forename: M
authors.initials: M
authors.lastname: Pardal
authors.affiliation: CESAM, Department of Chemistry, University of Aveiro, Campus de Santiago, 8005-135 Aveiro, Portugal.
authors.forename: A
authors.initials: A
authors.lastname: Duarte
authors.affiliation: CESAM, Department of Chemistry, University of Aveiro, Campus de Santiago, 8005-135 Aveiro, Portugal.
authors.forename: E
authors.initials: E
authors.lastname: Pereira
authors.affiliation: CNC, Department of Life Sciences, University of Coimbra, Apartado 3046, 3001-401 Coimbra, Portugal.
authors.forename: C M
authors.initials: CM
authors.lastname: Palmeira
mesh_terms: D000818:Animals; D004734:Energy Metabolism / Q000187:drug effects*; D005412:Flatfishes / Q000378:metabolism*; D008627:Mercuric Chloride / Q000493:pharmacokinetics / Q000633:toxicity*; D008930:Mitochondria, Liver / Q000187:drug effects* / Q000201:enzymology / Q000378:metabolism; D010084:Oxidation-Reduction; D010085:Oxidative Phosphorylation; D010101:Oxygen Consumption / Q000187:drug effects; D021541:Sea Bream / Q000378:metabolism*; D018675:Toxicity Tests; D014874:Water Pollutants, Chemical / Q000493:pharmacokinetics / Q000633:toxicity*
chemical_list: D014874:Water Pollutants, Chemical; D008627:Mercuric Chloride
keywords: Enzymatic activities; Marine fish; Mercury; Mitochondrial respiration