Neuroprotective effects of combined administration of coenzyme Q10 and vitamin-E in chronic celebral hypoperfusion-induced neurodegeneration in rats

Abstract

Alzheimer’s disease (AD) is the most common type of neurodegenerative diseases and the leading cause of dementia in the elderly. The number of people with neurodegenerative diseases is massively increasing. Currently, there is no prevention, cure or drugs to slow down the progression of AD. Numerous evidences have revealed the presence of oxidative stress in the beginning and progression of AD. Therefore, the potential of using natural antioxidants for prevention and treatment of AD has attracted considerable attention. Coenzyme Q10 (CoQ10) and vitamin E (Vit E) have been reported as powerful antioxidants and used as protective agents for various illnesses. In spite of significant results in experimental studies, which used single antioxidant in AD models, clinical trials have failed to recapitulate the promising outcomes documented in animal studies. Therefore, an efficient strategy would be the use of combination of antioxidants in the treatment of Alzheimer’s disease to provide synergetic effects and enough antioxidant action without the need for large and toxic doses of single antioxidants. This study assessed the neuroprotective effects of combination of CoQ10 with vitamin E in Chronic Cerebral Hypoperfusion-induced neurodegeneration (CCH-ND) rat model. After acclimatization, 27 Sprague Dawley rats weighing 200-250 g were divided into six groups. Group A – sham control, Group B – 2VO, group C – 2VO+E (treated daily with Vit E, 100 mg/kg, orally following 2VO) Group D CoQ10 (treated daily with CoQ10, 200 mg/kg, orally following 2VO), group E- CoQ10+E (treated with combination of CoQ10 and Vit E) and group F treated with coconut oil as vehicle. On the 8th week, all the rats were tested by Morris water maze cognitive test and then euthanized and the hippocampi were isolated. Viable neuronal cell count in the hippocampal region was estimated. The Isoprostane F2 (F2-IsoPs) levels were assessed in the brain homogenates to quantify the oxidative stress status. There was significant difference in neuronal cell death, memory and learning, and F2-Iso level in untreated 2VO group compared to the treated and sham groups. However, there was no statistically significant difference in neuroprotective effects of combination of vitamin E with CoQ10 and each one alone. To conclude, combination of antioxidants (Vit E and CoQ10) improve memory, neuronal cell viability and decrease antioxidant level, same as using each one alone and sham operated group in animal models of CCH.