Potential toxicity and mechanistic insights into organ-specific damage induced by iron oxide nanoparticles in Oryctolagus cuniculus

Abstract

Vibrating sample magnetometry (VSM), transmission electron microscopy (TEM), and X-ray diffraction (XRD)
were used to characterize iron oxide nanoparticles (IONPs) synthesized via co-precipitation. TEM showed that
the synthesized NPs had an average size of 13.8 nm and exhibited a saturation magnetization of 50.26 emu/gm,
while XRD confirmed their crystallinity. This study assessed the toxicological impacts of IONPs on hematology,
serum biochemistry, genotoxicity, and the histoarchitecture ailments in different visceral organs (liver, kidneys,
spleen, brain, and heart of rabbits (Oryctolagus cuniculus). A total of 16 healthy adult rabbits without infections
were randomly assigned to two groups (A and B). Group A was the control whereas group B received 0.5 mg/kg
bw of IONP dose once for 10 days via marginal ear vein. Visceral tissues and blood were obtained from each
rabbit on days 5 and 10 of trial. The results showed a significant reduction in antioxidant enzymes and an
increase in oxidative stress. The hematological profile indicated lower values of red blood cell counts,
hematocrit, lymphocyte, and monocyte while significantly higher values of total white blood cell counts and
neutrophil (%) in IONPs-treated rabbits. Serum biomarkers of the liver, kidneys, and heart exhibited escalated
concentrations in IONPs-treated rabbits. Histopathological examination revealed notable tissue alterations like
necrosis of hepatocyte, congestion, and bile duct hyperplasia in the liver, neuronal degeneration, necrosis, and
microgliosis in the brain, tubular degeneration, necrosis, and congestion in the kidneys and disorganization of
cardiac myofibers and edema in cardiac tissue. A significantly increased DNA damage was assessed in multiple
visceral organs of treated rabbits. In conclusion, our findings demonstrate that exposure to IONPs induces toxic
effects in multiple visceral organs including the kidneys, liver, spleen, heart, and brain in rabbits.