The protective effect of quercetin and it nanocrystal on anxiety-like behaviors induced by animal model of Alzheimer’s disease

Introduction: Alzheimer is a neurodegenerative disease which is characterized by progressive memory loss, diminished cognitive ability and behavioral disturbances such as anxiety-like behaviors. Quercetin is polyphenolic compound with antioxidant and neuroprotective effects.

Objective: Purpose of this study is evaluated antianxiety effect of quercetin and its nanocrystal in model of Alzheimer’s disease.

Methods: In present study, 49 male rats were divided into 7 groups: control (normal untreated rats), sham (received distilled water orally and saline intrcerebroventriculary), disease (received 10µg/rat STZ and distilled water) and disease treated with quercetin and its nanocrystal groups (received quercetin and its nanocrystal at doses of 10 and 25 mg/kg of body weight per day orally for four weeks after injection of STZ). Model of Alzheimer's disease induced by intracerebroventicular injection of STZ (icv-STZ) at doses of 10µg/rat. Elevated plus maze (EPM) test was used to assess anxiety-­like behaviors.

Results: Results indicated that icv-STZ injection significantly (P<0.001) decrease open arm times (%OAT) and open arm enters (%OAE) in the EPM test and in the groups treated with quercetin and its nanocrystal,these behavioral indexes significantly (P<0.001)  increased in the end of third and fourth weeks. Also in disease treated quercetin nanocrystal groups showed a significant decrease in anxiety-like behaviors compare with the disease treated quercetin groups.

Conclusion:

The study demonstrates the effectiveness of quercetin and its nanocrystal in preventing the anxiogenic-like behaviors induced by Alzheimer’s model of rat. Also results show that treatment of alzheimer's rat with quercetin nanocrystal is more effective than quercetin.