Strength and Aerobic Exercises Improve Spatial Memory in Aging Rats Through Stimulating Distinct Neuroplasticity Mechanisms

Abstract

Aging is associated with impaired cognition and memory and increased susceptibility to neurodegenerative disorders. Physical exercise is neuroprotective; however, the major evidence of this effect involves studies of only aerobic training in young animals. The benefits of other exercise protocols such as strength training in aged animals remains unknown. Here, we investigated the effect of aerobic and strength training on spatial memory and hippocampal plasticity in aging rats. Aging Wistar rats performed aerobic or strength training for 50 min 3 to 4 days/week for 8 weeks. Spatial memory and neurotrophic and glutamatergic signaling in the hippocampus of aged rats were evaluated after aerobic or strength training. Both aerobic and strength training improved cognition during the performance of a spatial memory task. Remarkably, the improvement in spatial memory was accompanied by an increase in synaptic plasticity proteins within the hippocampus after exercise training, with some differences in the intracellular functions of those proteins between the two exercise protocols. Moreover, neurotrophic signaling (CREB, BDNF, and the P75 receptor) increased after training for both exercise protocols, and aerobic exercise specifically increased glutamatergic proteins (NMDA receptor and PSD-95). We also observed a decrease in DNA damage after aerobic training. In contrast, strength training increased levels of PKCα and the proinflammatory factors TNF-α and IL-1β. Overall, our results show that both aerobic and strength training improved spatial memory in aging rats through inducing distinct molecular mechanisms of neuroplasticity. Our findings extend the idea that exercise protocols can be used to improve cognition during aging.

Effects of High- Versus Moderate-Intensity Training on Neuroplasticity and Functional Recovery After Focal Ischemia

“…Moreover, BDNF suppression, by injecting TrkB-FC, inhibited the increase of p75 NTR expression after axotomia reducing the neuronal survival 33 . Only one study found on aged rats that, following 8 weeks of endurance training, the p75 NTR level increased in parallel with an enhancement of BDNF expression 34 .…”

Physical activity reduces anxiety and regulates brain fatty acid synthesis

“…It is widely known that exercise improves mood and cognition, accelerating hippocampal neurogenesis in humans and in animal models. Voluntary wheel running correlates with an increase in the gene expression of neurotrophins and other growth factors [1,2], markers of synaptic plasticity, and downregulation of inflammatory factors [3], enhancing cognitive functions [4,5]. Beside its pro-cognitive role, exercise improves mood and libido but little has been known about why it has such a profound effect on the brain [6].…”

Kräftigung wider das Altern

“…Weiterhin konnte in anderen Studien beobachtet werden, dass eine Reduktion der Muskelmasse einen direkten Einfluss auf die Atrophie zerebraler Strukturen hat, was auch auf diesem Weg eine Verminderung kognitiver Funktionen bedingt [46] [47]. Zudem werden altersbedingte neurokognitive Veränderungen (Verschlechterungen) von peripheren Sarkopenie-bedingten Abbauprozessen katalysiert [43] [60]. Diese relativ neue Studie zeigte, dass aerobe Übungen eher die glutamatergen Signalwege modulieren, wobei Krafttraining Veränderungen in der Proteinkinase C (PKC: spielt wichtige Rolle bei der zellulären Signalweiterleitung) und in inflammatorischen Prozessen begünstigt [60] und somit in der Prävention und Therapie von neurodegenerativen Funktionen differenziert angewendet werden sollte (hierzu wird jedoch noch weitere Forschung benötigt).…”