title: Impairment of the mitochondrial oxidative phosphorylation system and oxidative stress in liver of crucian carp (Carassius auratus L.) exposed to microcystins.
abstract: Hepatotoxic microcystins (MCs) are produced by cyanobacteria in diverse water bodies and the pathophysiology includes induction of reactive oxygen species and adenosine triphosphate (ATP) depletion in cells. In this study, we evaluated MCs induced changes in the oxidative phosphorylation (OXPHOS) system in mitochondria of crucian carp liver. Fish were subdivided into two groups that were intraperitoneally injected with two doses of MCs (50 and 200 MC-LReq μg/kg bw) and were sacrificed at 1, 3, 12, 24, and 48 h postinjection. The activities of five enzyme complexes of electron transport chain and mRNA expression of mitochondrial-encoded genes (cox1, cox2, cox3, and atp6) were significantly reduced in a time-dependent pattern after injection. There were also changes in mitochondrial ultrastructure, decreases in ATPase activities and reduction in antioxidant level after MCs exposure. Disorder in the OXPHOS system and decreased activities of antioxidative enzymes might contribute to bioenergy deficiency and consequent hepatocyte damage induced by MCs.
authors.affiliation: Donghu Experimental Station of Lake Ecosystems, State Key Laboratory of Freshwater Ecology and Biotechnology of China, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan 430072, People's Republic of China.
authors.forename: Yanyan
authors.initials: Y
authors.lastname: Zhao
authors.forename: Ping
authors.initials: P
authors.lastname: Xie
authors.forename: Huihui
authors.initials: H
authors.lastname: Fan
authors.forename: Sujuan
authors.initials: S
authors.lastname: Zhao
mesh_terms: D000251:Adenosine Triphosphatases / Q000378:metabolism; D000818:Animals; D000975:Antioxidants / Q000378:metabolism; D000458:Cyanobacteria / Q000378:metabolism; D004579:Electron Transport / Q000187:drug effects; D006054:Goldfish / Q000378:metabolism*; D007274:Injections, Intraperitoneal; D008099:Liver / Q000187:drug effects / Q000201:enzymology / Q000378:metabolism; D052998:Microcystins / Q000633:toxicity*; D008930:Mitochondria, Liver / Q000187:drug effects* / Q000201:enzymology / Q000235:genetics / Q000378:metabolism*; D010085:Oxidative Phosphorylation / Q000187:drug effects*; D018384:Oxidative Stress / Q000187:drug effects*; D012333:RNA, Messenger / Q000096:biosynthesis / Q000235:genetics; D017382:Reactive Oxygen Species / Q000378:metabolism
chemical_list: D000975:Antioxidants; D052998:Microcystins; D012333:RNA, Messenger; D017382:Reactive Oxygen Species; C078588:microcystin; D000251:Adenosine Triphosphatases