title: Microcystin-LR retards gonadal maturation through disrupting the growth hormone/insulin-like growth factors system in zebrafish.
abstract: Recent studies have documented that microcystins (MCs) have potential toxic effects on growth and reproduction in fish. However, no systematic data exist on whether MCs cause gonadal development retardation through disrupting the growth hormone/insulin-like growth factors (GH/IGFs) system. To this end, zebrafish hatchlings (5 d post-fertilization) were exposed to 0, 0.3, 3 and 30µg/L microcystin-LR (MC-LR) for 90 d until they reached sexual maturity. Life-cycle exposure to MC-LR caused delayed ovarian maturation and sperm development along with ultrapathological lesions in the brain and liver. Moreover, the retarded gonadal development was accompanied by an inhibition of the GH/IGFs system, which was characterized by significant decreases in the transcriptional levels of brain gh (males only), hepatic igf2a and igf2b as well as gonadal igf1 (males only), igf3 and igf2r. These findings for the first time point to the influence of MC-LR on fish gonadal development via the GH/IGFs system. Also, sex-differential impairments suggested that gonadal development of males is more vulnerable than that of female to MC-LR. Our results provide evidence that MC-LR at environmentally relevant concentrations is able to induce impairments on fish gonadal development.
authors.affiliation: College of Fisheries, Huazhong Agricultural University, Wuhan 430070, PR China.
authors.forename: Jie
authors.initials: J
authors.lastname: Hou
authors.affiliation: College of Fisheries, Huazhong Agricultural University, Wuhan 430070, PR China.
authors.forename: Yujing
authors.initials: Y
authors.lastname: Su
authors.affiliation: College of Fisheries, Huazhong Agricultural University, Wuhan 430070, PR China.
authors.forename: Wang
authors.initials: W
authors.lastname: Lin
authors.affiliation: College of Fisheries, Huazhong Agricultural University, Wuhan 430070, PR China.
authors.forename: Honghui
authors.initials: H
authors.lastname: Guo
authors.affiliation: Donghu Experimental Station of Lake Ecosystems, State Key Laboratory for Freshwater Ecology and Biotechnology of China, Institute of Hydrobiology, The Chinese Academy of Sciences, Wuhan 430072, PR China.
authors.forename: Ping
authors.initials: P
authors.lastname: Xie
authors.affiliation: Donghu Experimental Station of Lake Ecosystems, State Key Laboratory for Freshwater Ecology and Biotechnology of China, Institute of Hydrobiology, The Chinese Academy of Sciences, Wuhan 430072, PR China.
authors.forename: Jun
authors.initials: J
authors.lastname: Chen
authors.affiliation: College of Fisheries, Huazhong Agricultural University, Wuhan 430070, PR China; Freshwater Aquaculture Collaborative Innovation Center of Hubei Province, Wuhan 430070, PR China. Electronic address: guzemao@mail.hzau.edu.cn.
authors.forename: Zemao
authors.initials: Z
authors.lastname: Gu
authors.affiliation: College of Fisheries, Huazhong Agricultural University, Wuhan 430070, PR China; Key Laboratory of Freshwater Animal Breeding, Ministry of Agriculture, Wuhan 430070, PR China; Freshwater Aquaculture Collaborative Innovation Center of Hubei Province, Wuhan 430070, PR China. Electronic address: foreverlili78@mail.hzau.edu.cn.
authors.forename: Li
authors.initials: L
authors.lastname: Li
mesh_terms: D000818:Animals; D001921:Brain / Q000187:drug effects / Q000473:pathology; D000458:Cyanobacteria; D004781:Environmental Exposure / Q000009:adverse effects; D004791:Enzyme Inhibitors / Q000633:toxicity; D005260:Female; D006066:Gonads / Q000187:drug effects* / Q000502:physiology; D013006:Growth Hormone / Q000378:metabolism*; D007334:Insulin-Like Growth Factor I / Q000378:metabolism; D008018:Life Cycle Stages; D008099:Liver / Q000187:drug effects / Q000473:pathology; D008297:Male; D008387:Marine Toxins; D052998:Microcystins / Q000633:toxicity*; D010053:Ovary / Q000187:drug effects / Q000502:physiology; D012098:Reproduction / Q000187:drug effects*; D013002:Somatomedins / Q000378:metabolism*; D013094:Spermatozoa / Q000187:drug effects / Q000502:physiology; D014874:Water Pollutants, Chemical / Q000633:toxicity*; D015027:Zebrafish / Q000378:metabolism / Q000502:physiology*
chemical_list: D004791:Enzyme Inhibitors; D008387:Marine Toxins; D052998:Microcystins; D013002:Somatomedins; D014874:Water Pollutants, Chemical; D007334:Insulin-Like Growth Factor I; C078588:microcystin; D013006:Growth Hormone; C057862:cyanoginosin LR
keywords: GH/IGFs axis; Life-cycle exposure; Microcystins; Reproductive development; Retardation