Evaluation of the Effect of Resistance Exercise and Donepezil on Some Neurotrophin-Induced Changes in Gene Expression and Trk Receptors in the Hippocampus of Rats with Alzheimer’s Disease

This study aimed to evaluate the impact of resistance exercise and donepezil on some neurotrophins gene expression and Trk receptors in the hippocampus of rats with Alzheimer’s disease (AD).

In this study, 32 male adult Wistar rats (mean weight: 230 - 280 g) were assigned into two groups of AD and control. The control and AD groups received normal saline and streptozotocin (STZ) through intraventricular injection, respectively. Then, six subgroups were considered: (1) control rest (Con); (2) control exercise (Con-Exe); (3) Alzheimer’s rest (Alz); (4) Alzheimer’s exercise (Alz-Exe); (5) Alzheimer’s donepezil (Alz-Don); and (6) Alzheimer’s donepezil-exercise (Alz-Don-Exe). Donepezil was fed daily at a dose of 1.5 mg/kg to the treated groups. The three subgroups of exercising rats received exercises for eight weeks (three times a week). Each day, the resting groups were managed to decrease stress impacts. Twenty-four hours after the last session of exercise by the eighth week, deep anesthesia was applied, and the rats' heads were severed.

Considering an error rate below 5% (P < 0.05) and a confidence of more than 95%, a significant difference was observed in BDNF, NT3, NGF, TrkA, and TrkB values between exercising and donepezil-exercise rats compared to AD group. These values were considerably greater for donepezil-exercising Alzheimer’s group. Besides, the donepezil group was not significantly different from the Alzheimer’s group.

Although the use of donepezil alone did not significantly increase the expression of the studied genes, the concomitant use of the drug and resistance training significantly increased the expression levels.