Therapeutic effects of Cinnamomum zeylanicum aqueous extract on cognitive deficits in a rat model of Alzheimer’s disease

Recent studies have shown Cinnamomum zeylanicum antioxidant/anti-inflammatory activities, and inhibition of tau accumulation and Amyloid beta (Aβ)   aggregation. Therefore, it seems that this plant can improve cognition in rat model of Alzheimer’s disease (AD). For this purpose, the ability of an aqueous extract of cinnamon in attenuating Aβ-induced learning impairment was evaluated in a rat model of AD.

Aβ-protein fragment 25-35 was injected into the CA1 region of rats’ hippocampus and the effect of different doses of cinnamon extract (5, 10, or 20 mg/kg) on cognitive function was assessed in the Morris water maze. Animals were subjected to 5 days of training; 4 days with the invisible platform to test spatial learning and the 5th day with the visible platform to test motivation and sensorimotor coordination.

The results showed an significant increase in escape latency, traveled distance, orientation angle and decrease in target quadrant entries in Aβ-received rats. Cinnamon extract was able to significantly reduce the effect of Aβ.

The results indicates learning and memory impairment in Aβ25-35 groups. These impairments were reversed by administration of Cinnamomum zeylanicum extract. Our results suggest that cinnamon may be a valuable agent for alleviating symptoms of Aβ.