Cadmium-induced ovarian pathophysiology is mediated by change in gene expression pattern of zinc transporters in zebrafish (Danio rerio)

• Published in: Chemico-biological interactions 2011-09, Vol.193 (2), p.172-179
• Main Authors: Chouchene, Lina, Banni, Mohamed, Kerkeni, Abdelhamid, Saïd, Khaled, Messaoudi, Imed
• Format: Article
• Language: English
• Subjects: adults; Animals; Cadmium; Cadmium - administration & dosage; Cadmium - metabolism; Cadmium - pharmacology; Cadmium - toxicity; Cation Transport Proteins - genetics; Cell Count; Danio rerio; Daniorerio; diet; Down-Regulation - drug effects; Down-Regulation - genetics; Female; fish; Freshwater; Gene expression; Gene Expression - drug effects; Gene Expression - genetics; gene expression regulation; genes; histology; histopathology; messenger RNA; metallothionein; Metallothionein - genetics; Metallothionein - metabolism; oocytes; Oocytes - pathology; Organ Size - drug effects; Ovarian Follicle - pathology; Ovary - drug effects; Ovary - metabolism; Ovary - pathology; Ovary - physiopathology; pathophysiology; protective effect; Reproductive toxicity; reproductive toxicology; toxicity; transporters; Up-Regulation - drug effects; Up-Regulation - genetics; Vitellogenesis - drug effects; Zebrafish; Zebrafish Proteins - genetics; Zinc; Zinc - administration & dosage; Zinc - metabolism; Zinc - pharmacology; Zinc transporters
• ISSN: 0009-2797; 1872-7786
• DOI: 10.1016/j.cbi.2011.06.010

► Expression of genes encoding ZnT1 and ZIP10 were examined in zebrafish co-exposed to Cd and Zn. ► Cd-exposure induced Zn depletion, decreased the expression of ZnT1 and caused up-regulation of ZIP10. ► Downregulation of ZnT1 and overexpression of ZIP10, increase ovarian Cd accumulation and consequently its toxicity. ► Co-exposure of zebrafish to Cd and Zn abolished ZnT1 down-regulation and increased ZIP10 mRNA level. This study explored the potential for expression pattern of genes encoding zinc (Zn) transporters to be involved in the cadmium (Cd)-induced reproductive toxicity in female of zebrafish. For this purpose, oocytes maturity and ovarian histology as well as Cd, Zn and metallothioneins (MTs) accumulation and expression of genes encoding Zrt-,Irt-related protein 10 (ZIP10), Zn transporter 1 (ZnT1) and zebrafish metallothionein (zMT) were examined in ovaries of adult zebrafish exposed to 0.4mg/L Cd in water and supplemented with Zn (5mgkg−1) in their diet for 21days. Cd-exposure decreased the expression of ZnT1 and caused up-regulation of ZIP10 and zMT gene expression. These changes were accompanied by increased Cd and MTs accumulation, decreased Zn contents as well as by histopathological damages in ovarian tissues. The co-exposure of fish to Cd and Zn abolished ZnT1 down-regulation and rendered a persistently increased ZIP10 mRNA level. This treatment also decreased Cd and MTs accumulation, reversed Cd-induced Zn depletion and partially restored Cd-induced histological changes in ovarian tissues. These results imply that the downregulation of ZnT1 as well as the overexpression of ZIP10, in responses to the ovarian Zn depletion induced by Cd, play a major role in Cd accumulation and consequently in its toxicity. The protective effect of dietary Zn supplementation against Cd-induced toxicity is mediated, at least in part, by the increase of Zn availability and subsequently the induction of ZnT1 gene expression.