title: Expression of c-fos and oxidative stress on brain of rats reared on food from mercury-selenium coexisting mining area.
abstract: Wanshan mercury mine is the largest mercury deposit in Guizhou Province of China, but there were few reports on mercury toxic effect in the mining area. In order to study the neurotoxicity of food from Wanshan mercury mine area and probe into the effect of food from Wanshan mercury miner area on the changes of brain oxidative damage and expression of c-fos gene. The rats were exposed to mercury contaminated food for 20 d. The content of malondialdehyde (MDA), superoxide dismutase (SOD), GSH-peroxidase (GSH-px) and Glutathione (GSH) in rat brain was measured, and the effect of mercury contaminated rice on the expression of c-fos mRNA in rat brain and the expression of c-FOS protein in cortex, hippocampus were observed using reverse transcription polymerase chain reaction (RT-PCR) and immunocytochemical methods. The results showed the levels of GSH, MDA, SOD and of GSH-dependent enzymes in the rat brain changed between exposure groups and control group; The mercury polluted rice induced significantly the expression of c-fos mRNA; the c-FOS positive cells in hippocampus and cortex of exposure groups were significant different from control group (P<0.01). It could be concluded that oxidative stress signals could contribute to the induction of immediate early genes (IEGs); free radicals and their by-products might not only cause oxidative damage, but also influenced gene expression; IEGs c-fos participated in the toxicity process of brain injury by mercury polluted food.
authors.affiliation: School of Environmental Science and Engineering, Shanghai Jiaotong University, China. jpcheng@sjtu.edu.cn
authors.forename: Jin-ping
authors.initials: JP
authors.lastname: Cheng
authors.forename: Wei-xuan
authors.initials: WX
authors.lastname: Hu
authors.forename: Xiao-jie
authors.initials: XJ
authors.lastname: Liu
authors.forename: Min
authors.initials: M
authors.lastname: Zheng
authors.forename: Wei
authors.initials: W
authors.lastname: Shi
authors.forename: Wen-hua
authors.initials: WH
authors.lastname: Wang
mesh_terms: D000818:Animals; D001921:Brain / Q000201:enzymology / Q000378:metabolism*; D002681:China; D004305:Dose-Response Relationship, Drug; D005260:Female; D005506:Food Contamination / Q000032:analysis*; D007150:Immunohistochemistry; D008297:Male; D008628:Mercury / Q000633:toxicity*; D008906:Mining; D012275:Oryza / Q000737:chemistry; D018384:Oxidative Stress / Q000187:drug effects*; D016760:Proto-Oncogene Proteins c-fos / Q000378:metabolism*; D011897:Random Allocation; D051381:Rats; D017207:Rats, Sprague-Dawley; D020133:Reverse Transcriptase Polymerase Chain Reaction / Q000379:methods; D012643:Selenium / Q000633:toxicity*
chemical_list: D016760:Proto-Oncogene Proteins c-fos; D008628:Mercury; D012643:Selenium