title: Effects and mechanisms of waterborne copper exposure influencing ovary development and related hormones secretion in yellow catfish Pelteobagrus fulvidraco.
abstract: The present study was conducted to determine the effects and mechanism of waterborne copper (Cu) exposure influencing ovary development and related hormones secretion in yellow catfish Pelteobagrus fulvidraco. To this end, two experiments were conducted. In Exp. 1, the partial cDNA sequences of three steroidogenesis-related genes (androgen receptor (ar), steroidogenic factor 1 (sf-1) and steroidogenic acute regulatory protein (star)) were firstly characterized from P. fulvidraco. The predicted amino acid sequences for the P. fulvidraco ar, sf-1 and star contained the main structural features characteristic in other species. In Exp. 2, P. fulvidraco were exposed to three waterborne Cu concentrations (control, 30μg/l and 60μg/l, respectively) for 56days. Sampling occurred on day 28 and day 56, respectively. On day 28, the levels of serum sex-steroid hormones (FSH and LH) and the mRNA levels of steroidogenesis-related genes (3β-hsd, cyp11a1, cyp17, cyp19a, sf-1 and star) were significantly increased in ovary of P. fulvidraco exposed to 30μg Cu/l. The immunohistochemical analysis showed the positive reaction of ER, VTG and aromatase in low dose exposure group. These indicated that in low dose and relative short-term exposure, Cu was beneficial. In contrast, 60μg Cu/l exposure significantly reduced the levels of serum FSH, LH, E2 and P, and the mRNA levels of ovarian 20β-hsd, cyp19a and erα in P. fulvidraco. On day 56, waterborne Cu concentration exposure reduced the levels of serum gonadotropins and sex hormones, and down-regulated the mRNA levels of steroidogenesis-related genes, indicating long-term Cu exposure had toxic effect on the secretion of sex-steroid hormone in P. fulvidraco. For the first time, our study cloned cDNA sequences of ar, sf-1 and star in P. fulvidraco, and demonstrated the effects and mechanism of waterborne Cu exposure influencing hormones secretion and synthesis in dose- and time-dependent manner in P. fulvidraco, which will help to understand the Cu-induced reproductive toxicity at both protein and transcriptional levels in fish.
authors.affiliation: Laboratory of Nutrition and Feed for Aquatic Economic Animals, Fishery College, Huazhong Agricultural University, Wuhan 430070, China; Freshwater Aquaculture Collaborative Innovative Center of Hubei Province, Wuhan 430070, China.
authors.forename: Li-Han
authors.initials: LH
authors.lastname: Zhang
authors.affiliation: Laboratory of Nutrition and Feed for Aquatic Economic Animals, Fishery College, Huazhong Agricultural University, Wuhan 430070, China; Freshwater Aquaculture Collaborative Innovative Center of Hubei Province, Wuhan 430070, China; Hubei Provincial Engineering Laboratory for Pond Aquaculture, Wuhan 430070, China. Electronic address: luozhi99@mail.hzau.edu.cn.
authors.forename: Zhi
authors.initials: Z
authors.lastname: Luo
authors.affiliation: Laboratory of Nutrition and Feed for Aquatic Economic Animals, Fishery College, Huazhong Agricultural University, Wuhan 430070, China; Freshwater Aquaculture Collaborative Innovative Center of Hubei Province, Wuhan 430070, China.
authors.forename: Yu-Feng
authors.initials: YF
authors.lastname: Song
authors.affiliation: Laboratory of Nutrition and Feed for Aquatic Economic Animals, Fishery College, Huazhong Agricultural University, Wuhan 430070, China; Freshwater Aquaculture Collaborative Innovative Center of Hubei Province, Wuhan 430070, China.
authors.forename: Xi
authors.initials: X
authors.lastname: Shi
authors.affiliation: Laboratory of Nutrition and Feed for Aquatic Economic Animals, Fishery College, Huazhong Agricultural University, Wuhan 430070, China; Freshwater Aquaculture Collaborative Innovative Center of Hubei Province, Wuhan 430070, China.
authors.forename: Ya-Xiong
authors.initials: YX
authors.lastname: Pan
authors.affiliation: Laboratory of Nutrition and Feed for Aquatic Economic Animals, Fishery College, Huazhong Agricultural University, Wuhan 430070, China; Freshwater Aquaculture Collaborative Innovative Center of Hubei Province, Wuhan 430070, China.
authors.forename: Yao-Fang
authors.initials: YF
authors.lastname: Fan
authors.affiliation: Laboratory of Nutrition and Feed for Aquatic Economic Animals, Fishery College, Huazhong Agricultural University, Wuhan 430070, China; Freshwater Aquaculture Collaborative Innovative Center of Hubei Province, Wuhan 430070, China.
authors.forename: Yi-Huan
authors.initials: YH
authors.lastname: Xu
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D002397:Catfishes / Q000254:growth & development* / Q000378:metabolism; D003300:Copper / Q000633:toxicity*; D018076:DNA, Complementary / Q000378:metabolism; D004305:Dose-Response Relationship, Drug; D005260:Female; D010053:Ovary / Q000187:drug effects* / Q000254:growth & development / Q000378:metabolism; D010750:Phosphoproteins / Q000096:biosynthesis / Q000378:metabolism*; D012333:RNA, Messenger / Q000378:metabolism; D011944:Receptors, Androgen / Q000096:biosynthesis / Q000378:metabolism*; D012733:Sex Differentiation; D054339:Steroidogenic Factor 1 / Q000096:biosynthesis / Q000378:metabolism*; D013997:Time Factors; D014874:Water Pollutants, Chemical / Q000633:toxicity*; D000098682:Steroidogenic Acute Regulatory Protein
chemical_list: D018076:DNA, Complementary; D010750:Phosphoproteins; D012333:RNA, Messenger; D011944:Receptors, Androgen; D054339:Steroidogenic Factor 1; D014874:Water Pollutants, Chemical; D000098682:Steroidogenic Acute Regulatory Protein; D003300:Copper
keywords: Cu; Pelteobagrus fulvidraco; Reproductive physiology; Steroidogenesis