Neuro-amelioration of cinnamaldehyde in aluminum-induced Alzheimer's disease rat model

Aluminum (Al) is a neurotoxic substance which has played an important role in the etiology, pathogenesis, and development of amyloid-β (Aβ) plaques. This study was carried out to evaluate the neuroprotective effect of aqueous cinnamon extract against aluminum chloride (AlCl₃)-induced Alzheimer's disease. Forty adult male albino rats, randomly divided into four equal groups. Control group; ACE200 group administered aqueous cinnamon extract (ACE) orally; AlCl₃ group received daily intraperitoneal (i.p.) injection of AlCl₃ for 60 days to induce neurotoxicity and AlCl₃ + ACE200 group received a combination of AlCl₃ and ACE in the same dose and route as previous groups. Aluminum administration significantly enhanced the memory impairment and the Aβ formation in the rat model. The cerebellum exhibited a significant reduced number of Purkinje cells, marked decrease in the density of dendritic arborization and prominent perineuronal spaces in the molecular layer. There was loss of dendritic spines, neurofibrillary degeneration, and appearance of neuritic plaques. Concomitant administration of AlCl₃ and ACE displayed an observable protection against these changes with progressive improvement in memory and intellectual performance. In conclusion, ACE may play a protective role against formation of amyloid-β plaques in cerebellum.