title: Effects of waterborne copper exposure on carnitine composition, kinetics of carnitine palmitoyltransferases I (CPT I) and mRNA levels of CPT I isoforms in yellow catfish Pelteobagrus fulvidraco.
abstract: The present study was conducted to determine the effect of waterborne copper (Cu) exposure on carnitine concentration, carnitine palmitoyltransferases I (CPT I) kinetics, and expression levels of four CPT I isoforms in the liver, muscle and heart of yellow catfish Pelteobagrus fulvidraco. Yellow catfish were exposed to four waterborne copper (Cu) concentrations (2 (control), 24 (low), 71 (medium), 198 (high) μg Cu/l, respectively) for 6weeks. Waterborne Cu exposure increased maximal reaction rates (Vmax) in the liver and muscle, but not in the heart. Michaelis-Menten constants (Km) tended to increase in the liver, but decreased in the heart after Cu exposure. The contents of total carnitine (TC) and acylcarnitine (AC) in the liver, and free carnitine (FC) in the muscle increased with increasing waterborne Cu concentrations, while FC content in the muscle declined with the increase of Cu levels. Waterborne Cu exposure also significantly influenced carnitine composition and profiles in heart. The mRNA expression of CPT Iα1a, CPT Iα1b and CPT Iα2a in the liver, and CPT Iα1a, CPT Iα1b and CPT Iβ in the muscle as well as CPT Iα1a in the heart were up-regulated by Cu exposure. Additionally, correlations were observed in the expression levels of CPT I isoforms and Km for carnitine, and between CPT I isoform expression and CPT I activity. To our knowledge, for the first time, the present study provided evidence that waterborne Cu exposure could influence carnitine composition, CPT I kinetics and mRNA levels of four CPT I isoforms in yellow catfish, which served to increase our understanding of the mechanisms underlying lipid catabolism during Cu exposure.
authors.affiliation: Key Laboratory of Freshwater Animal Breeding, Ministry of Agriculture of P.R.C., Fishery College, Huazhong Agricultural University, Wuhan 430070, China; Freshwater Aquaculture Collaborative Innovative Centre of Hubei Province, Wuhan 430070, China.
authors.forename: Qi-Liang
authors.initials: QL
authors.lastname: Chen
authors.affiliation: Key Laboratory of Freshwater Animal Breeding, Ministry of Agriculture of P.R.C., Fishery College, Huazhong Agricultural University, Wuhan 430070, China; Freshwater Aquaculture Collaborative Innovative Centre of Hubei Province, Wuhan 430070, China. Electronic address: luozhi99@mail.hzau.edu.cn.
authors.forename: Zhi
authors.initials: Z
authors.lastname: Luo
authors.affiliation: Key Laboratory of Freshwater Animal Breeding, Ministry of Agriculture of P.R.C., Fishery College, Huazhong Agricultural University, Wuhan 430070, China; Freshwater Aquaculture Collaborative Innovative Centre of Hubei Province, Wuhan 430070, China.
authors.forename: Cai-Xia
authors.initials: CX
authors.lastname: Liu
authors.affiliation: Key Laboratory of Freshwater Animal Breeding, Ministry of Agriculture of P.R.C., Fishery College, Huazhong Agricultural University, Wuhan 430070, China; Freshwater Aquaculture Collaborative Innovative Centre of Hubei Province, Wuhan 430070, China.
authors.forename: Jia-Lang
authors.initials: JL
authors.lastname: Zheng
authors.affiliation: Key Laboratory of Freshwater Animal Breeding, Ministry of Agriculture of P.R.C., Fishery College, Huazhong Agricultural University, Wuhan 430070, China; Freshwater Aquaculture Collaborative Innovative Centre of Hubei Province, Wuhan 430070, China.
authors.forename: Qing-Ling
authors.initials: QL
authors.lastname: Zhu
authors.affiliation: Key Laboratory of Freshwater Animal Breeding, Ministry of Agriculture of P.R.C., Fishery College, Huazhong Agricultural University, Wuhan 430070, China; Freshwater Aquaculture Collaborative Innovative Centre of Hubei Province, Wuhan 430070, China.
authors.forename: Wei
authors.initials: W
authors.lastname: Hu
authors.affiliation: Key Laboratory of Freshwater Animal Breeding, Ministry of Agriculture of P.R.C., Fishery College, Huazhong Agricultural University, Wuhan 430070, China; Freshwater Aquaculture Collaborative Innovative Centre of Hubei Province, Wuhan 430070, China.
authors.forename: Mei-Qin
authors.initials: MQ
authors.lastname: Zhuo
mesh_terms: D000818:Animals; D002331:Carnitine / Q000031:analogs & derivatives* / Q000032:analysis / Q000378:metabolism; D002334:Carnitine O-Palmitoyltransferase / Q000235:genetics / Q000378:metabolism*; D002397:Catfishes / Q000235:genetics / Q000378:metabolism*; D003300:Copper / Q000032:analysis / Q000633:toxicity*; D004784:Environmental Monitoring / Q000379:methods*; D007527:Isoenzymes / Q000235:genetics; D007700:Kinetics; D050356:Lipid Metabolism / Q000187:drug effects; D008099:Liver / Q000187:drug effects / Q000378:metabolism; D009132:Muscles / Q000187:drug effects / Q000378:metabolism; D012333:RNA, Messenger / Q000378:metabolism; D014874:Water Pollutants, Chemical / Q000032:analysis / Q000633:toxicity*
chemical_list: D007527:Isoenzymes; D012333:RNA, Messenger; D014874:Water Pollutants, Chemical; C116917:acylcarnitine; D003300:Copper; D002334:Carnitine O-Palmitoyltransferase; D002331:Carnitine
keywords: CPT I; Carnitine status; Copper exposure; Kinetics; Lipolysis; Pelteobagrus fulvidraco