Effect Of Long-term Intake Of Y～(3+) In Drinking Water On Antioxidant System And Gene Expression In Liver Of Rats

Aims: With widespread appliance of Rare Earths(REs), much attention was paid to the security of REs in recent years. In this paper, the effects of Y³⁺ in drinking water on antioxidant system and gene expression in liver of rat to provide more informations on evaluation of chronic toxicity and formulation of new Acceptable Daily Intake of REs.Methods: According to Acceptable Daily Intake of Rare Earth, wistar rats weredivided into three groups, which were given Y³⁺ at 5340mg·L^-1(high dose group), 53.4 mg·L^-1 (low dose group), and 0 mg· L^-1(control), respectively. DNA damage in peripheral blood lymphocyte cells of rats was evaluated by single cell gel electrophoresis (SCGE). The activity of SOD (superoxiden dismutase), CAT(catalase), ROS(ractive oxygen species) and the content of MDA (malondialdehyde) in rat liver were determinated by means of biochemistry. The gene expression in liver tissue was analyzed with oligonucleotide microarray.Results: (1) The CometLength in low dose and the TailLength and CometLength inhigh dose increased significantly compared with control (P<0.05). (2) No significantly changes in MDA, SOD, CAT, ROS were observed in low dose group, in contrast, greatly changes in MDA occurred in high dose group (P<0.05). (3) Compared to control, 304 of genes express differentially including 74 over-expressed genes and 230 under-expressed genes in high dose group, most are related to antioxidant system, signal transduction system, immunity, cyclin, DNA transcription and protein translation. 12 of them are related to oxidative damage including 2 over-expressed genes and 10 under-expressed genes.,such as CYP450 and GST genes. 195 of genes are found to express differentially including 88 over-expressed genes and 107 under-expressed genes in low dose group, of which, most are related to immunity, transcription and translation factor, signal transduction system, and ionic passage, etc.