title: Effects of dietary zinc on gene expression of antioxidant enzymes and heat shock proteins in hepatopancreas of abalone Haliotis discus hannai.
abstract: The expression patterns of different genes encoding antioxidant enzymes and heat shock proteins were investigated, in present study, by real-time quantitative PCR in the hepatopancreas of abalone Haliotis discus hannai fed with different levels of dietary zinc (6.69, 33.8, 710.6 and 3462.5 mg/kg) for 20 weeks. The antioxidant enzymes include Cu/Zn-superoxide dismutase (Cu/Zn-SOD), Mn-superoxide dismutase (Mn-SOD), catalase (CAT), mu-glutathione-s-transferase (mu-GST) and thioredoxin peroxidase (TPx). The results showed that the mRNA expression of these antioxidant enzymes increased and reached the maximum at the dietary zinc level of 33.8 mg/kg, and then dropped progressively. Expression levels of the heat shock proteins (HSP26, HSP70 and HSP90) firstly increased at 33.8 mg/kg dietary Zn level, and reached to the maximum at 710.6 mg/kg, then dropped at 3462.5 mg/kg (p<0.05). Excessive dietary Zn (710.6 and 3462.5 mg/kg) significantly increases the Zn content and significantly decreases the total antioxidant capacity (T-AOC) in hepatopancreas (p<0.05). These findings showed that dietary Zn (33.8 mg/kg) could highly trigger the expression levels of antioxidant enzymes and heat shock proteins, but excessive dietary Zn (710.6 and 3462.5 mg/kg) induces a high oxidative stress in abalone.
authors.affiliation: The Key Laboratory of Mariculture (Education Ministry of China), Ocean University of China, 5 Yushan Road, Qingdao 266003, P.R. China.
authors.forename: Chenglong
authors.initials: C
authors.lastname: Wu
authors.forename: Wenbing
authors.initials: W
authors.lastname: Zhang
authors.forename: Kangsen
authors.initials: K
authors.lastname: Mai
authors.forename: Wei
authors.initials: W
authors.lastname: Xu
authors.forename: Xiaoli
authors.initials: X
authors.lastname: Zhong
mesh_terms: D000818:Animals; D000975:Antioxidants / Q000378:metabolism; D002374:Catalase / Q000235:genetics; D004305:Dose-Response Relationship, Drug; D004798:Enzymes / Q000235:genetics*; D049851:Gastropoda / Q000201:enzymology / Q000235:genetics* / Q000378:metabolism; D015870:Gene Expression / Q000187:drug effects*; D005982:Glutathione Transferase / Q000235:genetics; D018840:HSP70 Heat-Shock Proteins / Q000235:genetics; D018841:HSP90 Heat-Shock Proteins / Q000235:genetics; D006360:Heat-Shock Proteins / Q000235:genetics*; D043143:Hepatopancreas / Q000201:enzymology / Q000378:metabolism*; D018384:Oxidative Stress / Q000187:drug effects; D054464:Peroxiredoxins / Q000235:genetics; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D020133:Reverse Transcriptase Polymerase Chain Reaction; D013482:Superoxide Dismutase / Q000235:genetics; D015032:Zinc / Q000008:administration & dosage / Q000494:pharmacology* / Q000633:toxicity
chemical_list: D000975:Antioxidants; D004798:Enzymes; D018840:HSP70 Heat-Shock Proteins; D018841:HSP90 Heat-Shock Proteins; D006360:Heat-Shock Proteins; D012333:RNA, Messenger; D054464:Peroxiredoxins; D002374:Catalase; D013482:Superoxide Dismutase; D005982:Glutathione Transferase; D015032:Zinc