Affiliations: School of Environmental Science and Engineering,
Shanghai Jiaotong University, Shanghai 200240, China | Department of Epidemiology, National Institute for
Minamata Disease, Minamata, Kumamoto 867-0008, Japan | School of Public Heath, Fudan University, Shanghai
200032, China
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.
