Effects of Eight Weeks of Endurance and Resistance Training on Hippocampal Neuroplasticity and Memory Performance in Alzheimer’s Male Rats
محورهای موضوعی : Journal of Physical Activity and Hormones
Mahnaz Navardi
1
,
Anahita Shabani
2
1 - Department of Physical Education and Sports Sciences, Ra.C., Islamic Azad University, Rasht, Iran
2 - General Practitioner, Medicafit Corrective Exercise & Sport Medicine Clinic, Rasht, Iran
کلید واژه: Alzheimer’s disease, endurance training, resistance training, hippocampus, memory, BDNF, neuroplasticity, rats,
چکیده مقاله :
Introduction: Alzheimer’s disease (AD) is characterized by progressive memory impairment and hippocampal neurodegeneration, primarily due to synaptic dysfunction and neuronal loss. Physical exercise has been proposed as an effective non-pharmacological strategy to improve neuroplasticity and cognitive performance. This study aimed to compare the effects of endurance and resistance training on hippocampal structure, neurotrophic factors, and memory function in Alzheimer’s male rats.
Material & Methods: Forty adults male Wistar rats (250–300 g) were randomly divided into four groups (n = 10 each): Control (C), Alzheimer sedentary (AD-S), Alzheimer + Endurance training (AD-END), and Alzheimer + Resistance training (AD-RES). Alzheimer’s disease was experimentally induced through intracerebral administration of neurotoxic agents. The endurance group performed progressive treadmill running (15–25 m/min, 60 min/day, 5 days/week), while the resistance group performed weighted ladder climbing (50–100% body weight, 8 repetitions/set, 5 days/week) for eight consecutive weeks. Cognitive performance was assessed using the Eight-Arm Radial Maze (RAM) and Y-Maze tests. Hippocampal tissues were analyzed for BDNF expression, Aβ deposition, and neuronal density using ELISA and histological methods.
Results: Alzheimer’s induction caused significant impairments in spatial and working memory, decreased hippocampal BDNF expression (↓47%, p < 0.01), and increased Aβ deposition (↑65%, p < 0.001) compared to the control group. Both endurance and resistance training markedly improved cognitive function and hippocampal structure relative to the sedentary Alzheimer group (p < 0.05). In RAM testing, total errors decreased from 7.4 ± 1.1 (AD-S) to 3.9 ± 0.8 (AD-END) and 4.3 ± 0.9 (AD-RES), while Y-maze alternation increased from 44 ± 6% to 68 ± 5% and 63 ± 6%, respectively. Endurance training induced higher hippocampal BDNF levels (+62%, p < 0.01) and synaptic plasticity, whereas resistance training more effectively reduced amyloid deposition (−39%, p < 0.05) and preserved neuronal morphology.
Conclusion: Eight weeks of endurance and resistance training significantly improved hippocampal neuroplasticity and memory performance in Alzheimer’s rats through distinct neurobiological mechanisms. Endurance training enhanced neurotrophic signaling and synaptic connectivity, while resistance training exerted stronger neuroprotective and anti-degenerative effects. Combining both modalities may represent an optimal strategy for mitigating Alzheimer-related cognitive decline.
Introduction: Alzheimer’s disease (AD) is characterized by progressive memory impairment and hippocampal neurodegeneration, primarily due to synaptic dysfunction and neuronal loss. Physical exercise has been proposed as an effective non-pharmacological strategy to improve neuroplasticity and cognitive performance. This study aimed to compare the effects of endurance and resistance training on hippocampal structure, neurotrophic factors, and memory function in Alzheimer’s male rats.
Material & Methods: Forty adults male Wistar rats (250–300 g) were randomly divided into four groups (n = 10 each): Control (C), Alzheimer sedentary (AD-S), Alzheimer + Endurance training (AD-END), and Alzheimer + Resistance training (AD-RES). Alzheimer’s disease was experimentally induced through intracerebral administration of neurotoxic agents. The endurance group performed progressive treadmill running (15–25 m/min, 60 min/day, 5 days/week), while the resistance group performed weighted ladder climbing (50–100% body weight, 8 repetitions/set, 5 days/week) for eight consecutive weeks. Cognitive performance was assessed using the Eight-Arm Radial Maze (RAM) and Y-Maze tests. Hippocampal tissues were analyzed for BDNF expression, Aβ deposition, and neuronal density using ELISA and histological methods.
Results: Alzheimer’s induction caused significant impairments in spatial and working memory, decreased hippocampal BDNF expression (↓47%, p < 0.01), and increased Aβ deposition (↑65%, p < 0.001) compared to the control group. Both endurance and resistance training markedly improved cognitive function and hippocampal structure relative to the sedentary Alzheimer group (p < 0.05). In RAM testing, total errors decreased from 7.4 ± 1.1 (AD-S) to 3.9 ± 0.8 (AD-END) and 4.3 ± 0.9 (AD-RES), while Y-maze alternation increased from 44 ± 6% to 68 ± 5% and 63 ± 6%, respectively. Endurance training induced higher hippocampal BDNF levels (+62%, p < 0.01) and synaptic plasticity, whereas resistance training more effectively reduced amyloid deposition (−39%, p < 0.05) and preserved neuronal morphology.
Conclusion: Eight weeks of endurance and resistance training significantly improved hippocampal neuroplasticity and memory performance in Alzheimer’s rats through distinct neurobiological mechanisms. Endurance training enhanced neurotrophic signaling and synaptic connectivity, while resistance training exerted stronger neuroprotective and anti-degenerative effects. Combining both modalities may represent an optimal strategy for mitigating Alzheimer-related cognitive decline.
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