Morphological and biochemical parameters in Wistar rats influenced by molybdenum and its oxide nanoparticles

Despite widespread use of nanoparticles in industry and medicine, there is very little information about how the newly developed nanomaterials interact with biological objects. Certain properties of the Mo-containing nanoparticles (NPs) suggest their possible toxic effect on warm-blooded animals. In this paper we compared the effect of Mo NPs (at 1 and 25 mg/kg) and its oxide MoO3 NPs (at 1.2 and 29 mg/kg), when administrated parenterally, on metabolic parameters and the exchange of chemical elements in Wistar laboratory rats. There, we assessed the red and white blood cell counts, the hemoglobin level, the activity of catalase (CAT) and superoxide dismutase (SOD) (for oxidative status), the ALT, AST, LDH, GGT, creatine kinase activity, blood creatinine, bilirubin and urea concentrations (for metabolic status) at days 1, 7 and 14. A day after Mo NPs and MoO3 NPs administration the number of blood leukocyte lowered by 11.3 % (Р < 0.05) and 58.5 % (Р < 0.01), respectively. Also, a decrease in monocyte number by 18.9 (Р < 0.05), 41.9 (Р < 0.01), 51.7 (Р < 0.05) and 83.3 % (Р < 0.001) as depending on NPs chemical composition and doses was characteristic, though on day 14 a significant difference to control (54.5 %, Р < 0.05) was found only for MoO3 NPs at a dose of 29 mg/kg. The number of thrombocytes was the highest on day 14 for the maximum dosage of both NPs leading to hindered blood microcirculation. The experiments also showed an increase in serum aminotransferases, GGT and LDH activity. In sum, we observed manifestations of oxidative stress, anemia and capillary-trophic insufficiency in the animals administrated with high doses of molybdenum and Mo oxide NPs. These signs were progressing and the most apparent for molybdenum oxide NPs. Given the comparable doses used, the molybdenum nanoparticles exhibit lower toxicity as compared to its oxide.