Influence of Chronic Coenzyme Q10 Supplementation on Cognitive Function, Learning, and Memory in Healthy and Diabetic Middle-Aged Rats

Abstract

Diabetes mellitus can induce impairment in learning and memory. Cognitive and memory deficits are common in older adults and especially in those with diabetes. This is mainly because of hyperglycemia, oxidative stress, and vascular abnormalities. Coenzyme Q10 (CoQ10) can decrease oxidative stress, hyperglycemia, and inflammatory markers, and improve vascular function. Therefore, the aim of the present study was to investigate the possible effects of CoQ10 on cognitive function, learning, and memory in middle-aged healthy and diabetic rats. Adult middle-aged male Wistar rats (390–460 g, 12–13 months old) were divided into 6 experimental groups. Diabetes was induced by a single i.p. injection of streptozotocin (60 mg/kg). CoQ10 (20 or 120 mg/kg, orally by gavage) was administered for 45 days. The cognitive function and learning memory of rats were evaluated using novel object recognition (NOR) and passive avoidance tests. The discrimination index of the NOR test in the diabetic groups receiving CoQ10 (20 or 120 mg/kg) and the healthy group receiving CoQ10 (120 mg/kg) was significantly higher than that in the control group. In addition, the step through latency was significantly longer and the time spent in the dark compartment was significantly shorter in the diabetic groups receiving CoQ10 than in the control group. CoQ10 supplementation can improve learning and memory deficits induced by diabetes in older subjects. In addition, CoQ10 at higher doses can improve cognitive performance in older healthy subjects.

Diosgenin Attenuates Cognitive Impairment in Streptozotocin-Induced Diabetic Rats: Underlying Mechanisms

“…The obtained findings of this research study confirm that diosgenin administration to STZ-diabetic rats could improve learning and memory disturbances through appropriate modulation of NF-κB/TLR4/Nrf2 and attenuation of astrogliosis biomarker, restoration of cholinergic function, and mitigation of oxidative and inflammatory responses in addition to its neuroprotective potential. DM-associated cognitive deficits have already been reported, as shown by the poor performance of diabetic animals in the passive avoidance test, Y-maze [39], radial arm maze [40, 41], and novel object discrimination tasks [42] which is also consistent with our obtained behavioral data.…”

Learning Difficulties and Oxidative Stress in Autism Spectrum Disorder: A Review of the Role of Nutritional Interventions

“…Coenzyme Q10 supplementation was effective in decreasing oxidative stress and related symptoms in autistic children [88]. CoQ10 supplementation has been reported to have enhancement effect on learning and memory in human and animal studies [89]. Abdelraouf et al [90] suggested that children with learning disabilities exhibit memory and linguistic deficits that could be linked to oxidative stress.…”

The Paradox of Coenzyme Q10 in Aging

“…This study indicated that CoQ 10 supplementation slightly but significantly reduced fasting blood glucose, although it does not support the existence of significant effects on fasting insulin and glycosylated hemoglobin [189]. Moreover, results from animal studies suggest that dietary CoQ 10 would prevent or mitigate diabetes complications [197,198]. In relation to other metabolic alterations, supplementation with CoQ 10 has also shown beneficial effects on the treatment of hypercholesterolemia and hypertriglyceridemia by modifying blood lipid concentration.…”