The effects of aluminium and selenium supplementation on brain and liver antioxidant status in the rat

This in vivo study was designed to investigate the potential of aluminium (Al), in the absence of added iron, to participate in either antioxidant or pro-oxidant events. Some markers of oxidative stress were determined in liver and brain of rats exposed to aluminium lactate, either alone or in the presence of dietary supplements of selenium (se) as selenite. Exposure to aluminium for 21 days resulted in a statistically significant (P<0.05) decrease in brain glutathione. However, a non-significant increase in hepatic glutathione was observed in animals supplemented with either Se or Al, but Al in combination with Se prevented this elevation. In the brain a statistically non-significant increase (P>0.05) was observed in the GSH content. Contrary to what is known, Al exposure resulted in statistically significant decrease (P<0.001) in lipid peroxidation as measured by production of malondialdehyde in both liver and brain. Aluminium exposure had no significant effect on the liver and brain superoxide dismutase activity. Results of the present study suggest that in rat aluminium exposure may have both pro-oxidant and antioxidant effect. Furthermore, Se supplementation may offer some protection against aluminium toxicity but this needs to be further elucidated.