Abstract

Background:
Ischemic stroke remains a major cause of morbidity and mortality worldwide, highlighting its significance as a critical public health concern. Oxidative stress plays a pivotal role in neuronal injury, and quercetin, a natural flavonoid with potent antioxidant properties, has shown promise as a neuroprotective agent. Intranasal administration provides a direct nose-to-brain delivery route, potentially enhancing brain delivery efficiency.

Aim:
This study aimed to evaluate the potential neuroprotective effects of intranasally administered quercetin-loaded bovine serum albumin–polydopamine nanoparticles (NPs) in a rat model of ischemic stroke.

Methods:
A total of 24 male Sprague–Dawley rats were divided into six groups using the Federer formula. Ischemic stroke was induced by middle cerebral artery occlusion for 60 minutes. Quercetin NPs were administered intranasally at 45 minutes post-induction. Neurological outcomes were assessed using the Bederson score at 24 and 48 hours post-induction. Brain tissue samples were collected for histopathological evaluation, malondialdehyde (MDA) quantification, and superoxide dismutase (SOD) activity measurement.

Results:
Rats receiving intranasal quercetin NPs (Groups 3–5) showed improved neurological scores at 48 hours compared with the untreated ischemic groups, which exhibited persistent deficits. Histopathological analysis revealed reduced neuronal necrosis in the treated groups. The biochemical analysis indicated a trend toward lower MDA levels and higher SOD activity in the quercetin-treated rats.

Conclusion:
Intranasal quercetin NPs have a potential neuroprotective effect, possibly associated with modulation of oxidative stress. However, the results should be considered preliminary, and further studies with larger sample sizes and more comprehensive outcome measures are required to confirm these findings.

Key words: Early-phase neuroprotection; Intranasal delivery; Ischemic stroke model; Quercetin nanoparticles.