Biogenic selenium nanoparticles target chronic toxoplasmosis with minimal cytotoxicity in a mouse model

Introduction. Nanoparticles (NPs) have numerous biological benefits due to their large surface-volume ratio and convenient entry into cells compared to other particles. Previous research has shown the antimicrobial properties of biogenic selenium NPs (SeNps) and their effects on cellular immunomodulatory cytokines that play a key role in controlling infections. Aim. This study aimed to evaluate the therapeutic effects of SeNPs against chronic toxoplasmosis in mice. Methodology. Infected mice with Toxoplasma gondii (Tehran strain) were orally treated with SeNPs at doses of 2.5, 5 and 10 mg kg�1 once a day for 14 days. On the fifthteenth day, the mean number of brain-tissue cysts and the mRNA levels of TNF-α, IL-12, IL-10, IFN-γ and inducible nitric oxide synthase (iNOS) in the mice of each group were recorded. Moreover, serum clinical chemistry factors in the treated mice were examined to determine the safety of SeNPs. Results. The mean number of tissue cysts was significantly (P<0.001) decreased in mice treated with SeNPs in a dose-dependent manner compared with the control group. The mRNA levels of inflammatory cytokines were significantly increased in mice treated with SeNPs at a dose of 10 mg kg�1 compared with the control subgroup (P<0.05). No significant variation (P>0.05) observed in clinical chemistry parameters among the mice in the control subgroup compared with those treated with SeNPs. Conclusion. The findings demonstrated the therapeutic effects of SeNPs with no considerable toxicity against latent toxoplasmosis in the mouse model. Nevertheless, further studies are obligatory to reveal the exact anti-Toxoplasma mechanisms of SeNPs. © 2020 The Author