Targeted neuroprotection with OX26-functionalized Epigallocatechin-3-gallate (EGCG)-stabilized se nanoparticles in a rat model of cerebral ischemia

Stroke remains one of the leading causes of death and long-term disability worldwide, underscoring the need for innovative therapeutic approaches. Smart drug delivery systems employing nanoparticles functionalized with targeting ligands and therapeutic agents offer promising strategies for mitigating cerebral ischemic damage. In this study, a multifunctional brain-targeted nanocarrier (OX26-MK801-EGCG@Se NPs) was designed and synthesized by stabilizing selenium nanoparticles (Se NPs) with epigallocatechin gallate (EGCG), conjugating the NMDA receptor antagonist MK-801, and functionalizing the surface with the transferrin receptor-targeting monoclonal antibody OX26. Nanoparticles were synthesized via the reduction of selenious acid using ascorbic acid in the presence of EGCG, followed by PEG-carboxylic acid-mediated conjugation of MK-801 and OX26. Structural and physicochemical characterization was conducted using scanning transmission electron microscopy (STEM), dynamic light scattering (DLS), zeta potential analysis, Fourier-transform infrared spectroscopy (FTIR), and energy-dispersive X-ray spectroscopy (EDX). In vivo experiments were carried out on 68 male Wistar rats randomly assigned to Sham, Ischemia/Reperfusion (IR), IR + OX26-EGCG@Se NPs, and IR + OX26-MK801-EGCG@Se NPs groups. A transient middle cerebral artery occlusion (MCAO) model was established with 90-min occlusion followed by 72-h reperfusion. Nanoparticles (1000 µg/mL) were administered intraperitoneally 1 h prior to ischemia induction. Behavioral assessments included the open field and novel object recognition tests. Brain tissue was then analyzed for glutamate and Ca levels (ELISA), infarct volume (TTC staining), and NMDAR1, NMDAR2A, and AMPAR1 expression (immunohistochemistry). The findings revealed that both nanoparticle treatments significantly improved motor and cognitive outcomes, reduced glutamate and Ca²⁺ accumulation, inhibited NMDA/AMPA receptor overactivation, and decreased infarct volume. These results suggest that multifunctional, targeted nanoparticle systems represent a promising therapeutic strategy for ischemic stroke and related neurological disorders.