Alzheimer's disease (AD) is a
neurodegenerative disease with
cognitive impairment. Oxidative stress in neurons is considered as a reason for development of AD.
Antioxidant agents such as
quercetin slow down AD progression, but the usage of this
flavonoid has limitations because of its low bioavailability. We hypothesized that
quercetin-conjugated superparamagnetic iron oxide nanoparticles (QT-SPIONs) have a better
neuroprotective effect on AD than free
quercetin and regulates the
antioxidant, apoptotic, and APP gene, and miRNA-101. In this study, male Wistar rats were subjected to
AlCl3,
AlCl3 + QT,
AlCl3 + SPION, and
AlCl3 + QT-SPION for 42 consecutive days. Behavioral tests and qPCR were used to evaluate the efficiency of treatments. Results of behavioral tests revealed that the intensity of
cognitive impairment was decelerated at both the middle and end of the treatment period. The effect of QT-SPIONs on learning and
memory deficits were closely similar to the control group. The increase in expression levels of APP gene and the decrease in mir101 led to the development of AD symptoms in rats treated with
AlCl3 while these results were reversed in the
AlCl3 + QT-SPIONs group. This group showed similar results with the control group. QT-SPION also decreased the expression levels of
antioxidant enzymes along with increases in expression levels of anti-apoptotic genes. Accordingly, the
antioxidant effect of QT-SPION inhibited progression of
cognitive impairment via sustaining the balance of
antioxidant enzymes in the hippocampus of AD model rats.