Assessment of the role of α-lipoic acid against the oxidative stress of induced iron overload

Abstract

This work was aimed to study the protective role of α-lipoic acid against the oxidative damage of induced iron overload. Iron (Fe) overload is a complication of the treatment, by chronic transfusion, of a number of genetic diseases associated with inadequate red cell production (anemias) and of other genetic diseases that lead to excessive iron absorption from the diet. Male rats were injected ip with 5 mg/kg body weight ferrous sulfate for 50 days. The animals were injected ip with α-lipoic acid 20 mg per kg body weight for 21 days. Serum iron, Total Iron Binding Capacity (TIBC), Malonyldialdehyde (MDA), Electron paramagnetic resonance (EPR) spectroscopy, UV-visible absorption spectrum of hemoglobin and osmotic fragility were studied. Results showed significant increase in serum iron, total iron binding capacity, and malonyldialdehyde levels in iron-loaded rats. Treatment with lipoic acid (LA) resulted in decreasing serum iron and TIBC levels by 47%and 29% respectively. At the same time the lipoic acid decreased the level of the MDA in liver, brain and plasma by 54%, 42% and 74% respectively. Also LA diminished the effect of iron-induced free radicals on erythrocyte membrane integrity; it decreased the elevated average osmotic fragility and decreased the elevated rate of hemolysis. Results from UV-visible spectrophotometric measurement of hemoglobin revealed that no oxidative changes of hemoglobin occurred in iron-loaded rats. EPR spectra showed increased in non-heme ferric ions Fe+3 and free radicals in iron-loaded rats. Whereas the injection of the lipoic acid leads to decreased in such toxic result. In conclusion, these observations suggested that lipoic acid might be a beneficial antioxidant that can be effective for limiting damage from oxidative stress of iron overload.

Keywords

• Lipoic acid
• Iron overload
• MDA
• EPR
• TIBC
• Osmotic fragility
• Hemoglobin absorption spectrum