Assessment of the therapeutic efficacy of zinc oxide nanoparticles on chronic toxoplasmosis in murine model

Background: Toxoplasmosis remains a major global health problem with limited therapeutic options for chronic cases associated with immunodeficiency. These highlight the need for effective alternative therapies. Objective: To assess the anti-Toxoplasma effects of zinc oxide nanoparticles (ZnO NPs) and spiramycin, individually and in combination. Materials and Methods: Experimental Swiss albino mice were divided into 5 groups: G1, non-infected control; G2, infected control; G3, infected and spiramycin treated; G4, infected and treated with ZnO NPs; G5, infected and treated with spiramycin and ZnO NPs. The treatment effects were evaluated by assessing their impact on the parasite burden and histopathological changes in the brain and liver, as well as their immunomodulatory and antioxidant effects. Results: Oral ZnO NPs and spiramycin administration each induced a significant reduction of brain cyst counts, and the highest impact was noticed in the combination therapy group. Their administration also showed immunomodulatory effects by modulating TNF-α and IL-1β expression in brain and liver tissues. Moreover, treatments enhanced the oxidative stress and histopathological alterations in these tissues. The combination therapy achieved the best therapeutic impacts in all studied parameters. Conclusion: Our results revealed that ZnO NPs were effective against T. gondii, offering a promising antioxidant and anti-inflammatory adjunct therapy in parasitic diseases. Moreover, the highest therapeutic impact was observed with combined treatment indicating ameliorative synergistic effects.