[Effect of iron nanoparticles on free radical oxidation process in blood of rats with Pliss lymphosarcoma]

The use of metal nanoparticles (NPs) for cancer treatment requires careful examination of their biological effects. The aim of this study was to determine parameters of oxidative processes in the blood of tumor-bearing animals treated with metallic iron NPs only. The markers of antioxidant status and accumulation of lipid peroxidation products were measured in erythrocytes and blood plasma of rats with Pliss lymphosarcoma (PLS) and intact rats. PLS animals were treated eight times with iron NPs (at a dose of 1.25 mg/kg bw (main group), rats of the control group received saline (0.3 ml). In control animals, an increase in malondialdehyde (MDA) was observed in red blood cells (RBC) by 45%; this was accompanied by compensatory increase in reduced glutathione (GSH) and catalase by 24% and 14.3%, respectively (p<0.05). In plasma an increase in MDA by 167.4% (p<0.01) and a decrease in oxidase activity of ceruloplasmin (CP) by 36.8% (p<0.001) were found. In the main group there was a decrease of accumulation of lipid peroxidation products in the blood. Intensity of detected changes depended on the antitumor effect: rats with growing LSP showed a tendency to the decrease in the RBC MDA level and normalization of plasma MDA; in animals with LSP regression this marker did not differ from normal values. In all animals of the main group the CP content was basically the same as in intact rats while GSH increased in the group without therapeutic effect (by 218.6%) and in the group with the effect by 69% (versus normal values; p<0.01). SOD activity in the rats with LSP growth significantly increased (by 42%), in the rats with regression decreased (by 30%) with subsequent normalization. Thus, administration of iron NPs caused activation of the antioxidant system in blood and a significant decrease in the manifestations of oxidative stress associated with tumor growth.