Purpose: Nasal galantamine hydrobromide (GH)/chitosan complex nanoparticles (CX-NP2) could have an improved therapeutic potential for managing Alzheimer's disease (AD). The current study aimed to investigate if the complexation reaction between GH and chitosan altered the pharmacological and toxicological profiles of the parent drug; GH.
Methods: The nasal administration of CX-NP2 to male Wistar rats for 12 consecutive days was compared to negative control group, and oral and nasal GH solutions treated groups in 3 mg/kg daily GH dose. Brain acetylcholinesterase (AChE) protein level and activity were assessed. The in vivo toxicity of CX-NP2 was evaluated via monitoring the clinical signs throughout the study. Histopathological examination of brain sections was performed. The intracellular localization of CX-NP2 within brain neurons was investigated using transmission electron microscopy.
Results: GH/chitosan complexation did not negatively alter the pharmacological efficiency of GH. Intriguingly, nasal CX-NP2 exhibited a significant decrease of AChE protein level and activity in rat brains compared to the oral and nasal GH solutions. No toxicity signs or histopathological manifestations were noticed. The nanoparticles were found intracellularly in the brain neurons.
Conclusion: The pharmacological efficacy and in vivo safety of nasal CX-NP2 confirm their promising potential to contribute to the management of AD intranasally.
Keywords: Alzheimer’s disease; chitosan nanoparticles; galantamine; in vivo toxicity; intranasal route.