Effects of Manganese on Lipid Peroxidation and Compositional Changes of Fatty Acids in Hippocampus of Rat Brain

ABSTRACT

BACKGROUND: To investigate the effect of manganese on lipid peroxidation and compositional changes of fatty acids in hippocampus of rat brain. METHODS: Seven rats in experimental group were given with MnCl2 intraperitoneally for 4 weeks (4 mg/kg once daily, 5 days per week). Twenty four hours after the last injection, rats were decapitated and, hippocampus were separated from the rat brain. RESULT: In Mn-treated group, manganese concentrations increased significantly in the hippocampus by 222% compared with control group (P<0.01). MDA concentrations increased significantly by 149% compared with control group (P<0.05). Among fatty acids, total n-6 polyunsaturated fatty acids (PUFAs) increased significantly by 237% compared with control group (P<0.05). Linoleic acid (LA) and arachidonic acids (AA) increased by 213%, 238% (P<0.05, P<0.01, respectively). Among n-3 PUFAs except linolenic acids, eicosapentanoic acid(EPA) and docosahexanoic acids (DHA) decreased significantly by 70%, 50% respectively compared with control group (both P<0.01). CONCLUSION: Our results suggest that manganese may cause compositional changes of fatty acids in hippocampus of rat brain. Characteristics of fatty acids compositional changes by manganese were the decrease of EPAs and DHAs (n-3 PUFAs), and increase of AA and LA (n-6 PUFAs). These changes with the increase of MDA, suggest that manganese neurotoxicity is caused by lipid peroxidation.