Folic Acid and Coenzyme Q10 Ameliorate Cognitive Dysfunction in the Rats with Intracerebroventricular Injection of Streptozotocin

Document Type: Original Article


1 Department of Basic Sciences, Isfahan Payame Noor University, Isfahan, Iran

2 Department of Physiology, School of Medicine, Isfahan University of Medical Sciences, Isfahan, Iran

3 Biosensor Research Centre, Isfahan University of Medical Sciences, Isfahan, Iran

4 Department of Basic Sciences, Islamic Azad University Khorasgan Branch, Isfahan, Iran


The present study aimed to investigate the effects of a fat soluble antioxidant, coenzyme Q10 (CoQ10) and folic acid on learning and memory in the rats with intracerebroventricular injection of streptozotocin (ICV-STZ), an animal model of sporadic type of Alzheimer's disease.
Materials and Methods
The lesion groups were injected bilaterally with ICV-STZ (1.5 mg/kg b.wt., in normal saline). In the treated groups, rats received folic acid (4 mg/kg; i.p.) or CoQ10 (10 mg/kg; i.p.), either alone or together, for 21 days. Passive avoidance learning test was used for evaluation of learning and memory.
The results showed that learning and memory performance was significantly impaired in the rats with ICV-STZ (P< 0.001), however CoQ10 and folic acid, either alone or together, prevented impairments significantly (P< 0.001), as there was not any significant difference between these treated lesion groups and control group.
The present results suggest that CoQ10 and folic acid have therapeutic and preventive effects on cognitive impairments in Alzheimer’s disease.


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