Effect of 12-week vanadate and magnesium co-administration on chosen haematological parameters as well as on some indices of iron and copper metabolism and biomarkers of oxidative stress in rats.

Changes in some blood parameters after 12-week administration of sodium metavanadate (SMV; 0.125mgV/ml) or/and magnesium sulphate (MS; 0.06mgMg/ml) in drinking water were studied in outbred male Wistar rats (16 rats/each group) to explore the probable mechanism(s) underlying SMV toxicity and check whether Mg at the level selected during SMV co-administration can protect, at least in part, from a possible deleterious action of SMV. Exposure to SMV alone and in combination with MS (a) led to a decrease in fluid and food intake and body weight gain; (b) predisposed the animals to the development of microcytic-hypochromic anaemia (with excessive liver and spleen Fe deposition, unaltered plasma Fe level and enhanced Zn concentration in the erythrocytes (RBCs) characterized by a reduced haematocrit (Ht) index and haemoglobin (Hb) level, unchanged erythrocyte and reticulocyte count, anisocytosis, lowered total iron binding capacity (TIBC) and elevated transferrin saturation (TS); (c) disturbed Cu homeostasis, but (d) did not influence the leukocyte count and the plasma total antioxidant status (TAS). We suggest that abnormal metabolism and accumulation of Fe as well as an altered Cu status and the RBC Zn level might lead to defective Fe utilization and be a factor promoting the development of Fe-utilization anaemia. The disturbances in the antioxidative capacity reported previously in rats' RBCs after SMV intoxication (Ścibior, Zaporowska, Environ. Toxicol. Pharmacol. 30 (2010) 153-161) may suggest that oxidative stress (OS) could also be, in part, involved in the mechanism responsible for the development of anaemia. The Mg dose ingested in combination with V under SMV-MS co-administration (a) was able to decrease, to some extent, the V concentration in the blood, (b) normalized the RBC Mg and Fe levels and (c) restored the values of some parameters of the Fe status near the control values. These results allow a supposition that a higher Mg dose consumed during SMV exposure could have better protective potential and be more effective in limiting the SMV toxicity observed.