Background: Excessive use of diazinon, as an organophosphate pesticide (OP), contributes
to cytotoxic and pathologic cellular damage and, in particular, oxidative stress. However,
metal-oxide nanoparticles (NPs), such as cerium oxide (CeO2) and yttrium oxide (Y2O3),
with the property of free radical scavenging demonstrated beneficial effects in the alleviation of
oxidative stress biomarkers.
Objective: The aims of this study include evaluating beneficial effects of CeO2 NPs, Y2O3 NPs,
and their combination against diazinon-induced oxidative stress in different tissues of brain,
heart, lung, kidney, liver, and spleen.
Methods: Eight randomized groups of 6 adult male Wistar rats were formed. Each group of rats
administered a different combination of diazinon, CeO2 and Y2O3 NPs daily and levels of oxidative
stress markers, such as reactive oxygen species (ROS), lipid peroxidation (LPO), total
thiol molecules (TTM) and total anti-oxidant power (TAP) and catalase enzyme, were measured
after 2 weeks of the treatment.
Results: Measurements of the mentioned markers in the brain, heart, lung, kidney, liver, and
spleen showed that the administration of NPs could significantly alleviate the oxidative stress
induced by diazinon. However, the findings of this study illustrated that the combination of
both CeO2 and Y2O3 NPs led to a better reduction in oxidative stress markers.
Conclusion: Sub-acute exposure of diazinon in rats led to increased levels of oxidative stress
markers in pivotal tissues such as the brain, heart, lung, kidney, liver, and spleen. CeO2 and
Y2O3 NPs neutralize the oxidative stress to compensate diazinon-induced tissue damages.
Lay Summary: Organophosphate pesticides (OPs), which are mainly used for pest control,
are responsible for the entry of pesticides into the human food cycle. Organophosphate such as
diazinon increases the molecular biomarkers of oxidative stress inside the cells of vital tissues
such as the heart, liver, lungs, etc. Metal oxide nanoparticles (NPs) such as cerium oxide (CeO2)
and yitrium oxide (Y2O3) can have free radical scavenging potential under oxidative stress and
through various mechanisms. Although these nanoparticles reduce oxidative stress, it should be
borne in the design of the study that additional doses of these substances reverse the beneficial