METHODS: Amoebicidal assays were performed to determine whether metal oxide nanoparticles inhibit amoebae viability. Encystation assays were performed to test whether metal oxide nanoparticles inhibit cyst formation. By measuring lactate dehydrogenase release, cytotoxicity assays were performed to determine human cell damage. Hoechst 33342/PI staining was performed to determine programmed cell death (apoptosis) and necrosis in A. castellanii.
RESULTS: TiO2-NPs significantly inhibited amoebae viability as observed through amoebicidal assays, as well as inhibited their phenotypic transformation as evident using encystation assays, and showed limited human cell damage as observed by measuring lactate dehydrogenase assays. Furthermore, TiO2-NPs altered parasite membranes and resulted in necrotic cell death as determined using double staining cell death assays with Hoechst33342/Propidium iodide (PI) observed through chromatin condensation. These findings suggest that TiO2-NPs offers a potential viable avenue in the rationale development of therapeutic interventions against Acanthamoeba infections.