Biocompatibility of Nickel Ferrite Nanoparticles on Systemic and Testicular Cells

Nickel ferrite nanoparticles (NPs) are chemically stable and have a surface suitable for functionalization, making them potential biotechnological tools in male reproduction. Herein, the nickel ferrite (FeNi) NPs were synthesized by the hydrothermal method and presented colloidal stability, low aggregation, high crystallinity, and superparamagnetic behavior at room temperature. At a dose of 500 μg/mL, FeNi NPs reduced the viability of systemic and male reproductive cells at all time points. We selected 100 μg/mL to further investigate its effects on testicular cells, as it was safe for VERO and AML-12 cells. For male reproductive cells, we observed that the selected FeNi NP dose significantly increased cell death by apoptosis and necrosis in Leydig cells, and by apoptosis in germ cells. We observed rapid internalization of FeNi NPs in both cell types within the first 5 min of exposure. Transmission electron microscopy confirmed their presence in the cytoplasm and within vesicles, suggesting internalization via passive diffusion and endocytosis. Additionally, phagosome formation was noted in TM3 cells. The rapid and extensive internalization of these nanoparticles within testicular cells may result in cellular apoptosis. We also observed an increase in reactive oxygen species after exposure of male reproductive cells to FeNi NP. These findings provide a foundation for future investigations into the biomedical applications of FeNi nanoparticles in reproductive cells.