Background: Anosmia is a common annoying problem that affects quality of life. Nanoparticles act as nanocarriers that
deliver potent drug payloads at a controlled rate at the target site.
Purpose: This current work aimed to evaluate the potential preventive benefits of Quercetin (QU) versus Quercetin-loaded
chitosan nanoparticles (QU-CSNPs) on an experimental rat model of anosmia and shed insight on its protective mechanisms.
Methods: Forty rats were randomly divided into four groups, the Control group, the Zinc sulfate (ZnS) group, the ZnS+QU
group, and the ZnS+QU-CSNPs group. Behavioral assessment was carried out. Olfactory mucosae and bulbs were collected
for biochemical, histological, immunohistochemical, and morphometric analysis.
Results: The ZnS group showed behavioral alternation, decreased glutathione levels, increased malonaldehyde, and tumor
necrosis factor-α levels. Olfactory mucosa and bulb showed histological alterations, as well as a significant increase in COX-
2 immune-expression and decrease in PCNA and SOX2 expression. The ZnS+QU-CSNPs group showed amelioration in
previously mentioned parameters and histological alternation than the ZnS+QU group.
Conclusions: QU-CSNPs has prophylactic effects in an anosmia model than QU via its anti-inflammatory and antioxidant
effects. This could pave the way for additional studies to investigate further mechanisms underlying the potential beneficial
effects of QU-CSNPs and bring up a new line for anosmia therapy.