Exercise-induced hippocampal anti-inflammatory response in aged rats

Abstract

Aging is often accompanied by cognitive decline, memory impairment and an increased susceptibility to neurodegenerative disorders. Most of these age-related alterations have been associated with deleterious processes such as changes in the expression of inflammatory cytokines. Indeed, higher levels of pro-inflammatory cytokines and lower levels of anti-inflammatory cytokines are found in the aged brain. This perturbation in pro- and anti-inflammatory balance can represent one of the mechanisms that contribute to age-associated neuronal dysfunction and brain vulnerability. We conducted an experimental study to investigate whether an aerobic exercise program could promote changes in inflammatory response in the brains of aged rats. To do so, we evaluated the levels of tumor necrosis factor alpha (TNFα), interleukin 1 beta (IL1β), interleukin 6 (IL6) and interleukin 10 (IL10) in the hippocampal formation of 18 month old rats that underwent treadmill training over 10 consecutive days. Quantitative immunoassay analyses showed that the physical exercise increased anti-inflammatory cytokine levels IL10 in the hippocampal formation of aged rats, when compared to the control group. The hippocampal levels of pro-inflammatory cytokines IL1β, IL6 and TNFα were not statistically different between the groups. However, a significant reduction in IL1β/IL10, IL6/IL10 and TNFα/IL10 ratio was observed in the exercised group in relation to the control group. These findings indicate a favorable effect of physical exercise in the balance between hippocampal pro- and anti-inflammatory during aging, as well as reinforce the potential therapeutic of exercise in reducing the risk of neuroinflammation-linked disorders.

Comparison of hippocampal interleukin-6 immunoreactivity after exhaustive exercise in both exercise-trained and untrained rats

“…Their important roles in all critical hippocampal functions, including learning and memory, synaptic plasticity, neurogenesis, and brain aging, have been demonstrated previously (28). Physical exercise has favorable effects in the balance between hippocampal pro-and antiinflammatory cytokines during aging and is thought to play a preventive and curative role on various inflammatory nervous system disorders through these compensatory effects (29). In recent years, there have been many studies published on the proinflammatory functions of the cytokine IL-6 in the pathogenesis of several neurodegenerative disorders.…”

Physical Activity and Serum Cytokines Levels in Depressed Individuals - Gender Differences

“…Physical exercise and the practice of non-structured physical activities [10,11] have been hypothesized as neuromodulators of anti-and pro-inflammatory cytokines, reducing IL-6 [10,11] and TNF-α [11] levels and increasing the concentration of IL-10 [12,13]. Thus, the aim of this study is to investigate the relationship between the habitual practice of leisure-time activities and the serum levels of IL-6, IL-10, and TNF-α in individuals diagnosed with depression, considering the difference between genders.…”

Correlação dos parâmetros endócrinos e comportamentais em cadelas abandonadas em programa de ressocialização

“…These findings suggest that training kept standardized and higher cortisol levels (BEERDA et al, 1999b;NORMANDO et al, 2009;ASCHBACHER et al, 2013), probably resulting in an anti-inflammatory action and featuring an eustress as described previously (BROOM, 1988;ACCO;PACHALY;BACILA, 1999;KUNZ-EBRECHT et al, 2003;ASCHBACHER et al, 2013). The constancy of salivary IL6 levels in trained animals could also be explained by neuroendocrine mechanisms, which involved proinflammatory (IL6) and anti-inflammatory cytokines (IL10) (DE ALMEIDA et al, 2013;GOMES DA SILVA et al, 2013). Aerobic exercise performed daily in the morning induces an increase of anti-inflammatory cytokines and reduces the pro-inflammatory ones, especially in the hippocampus and cerebellum ).…”

“…should remain low to avoid emotional and systemic disturbances (MEYER; DA SILVA, 1999;CARROLL et al, 2011;DE ALMEIDA et al, 2013;GOMES DA SILVA et al, 2013). Sheltered dogs present behavior pattern similar to that of owned dogs, although interaction with the environment and other dogs were greater.…”

“…Common sense about cortisol elevations as negative events or preventing dogs from undergoing stress may be partially incorrect since hormonal fluctuations can make dogs feel new environmental challenges (HAVERBEKE et al, 2008;ASCHBACHER et al, 2013;GOMES DA SILVA et al, 2013). Exaggerated hormonal elevations may lead to health problems, as low immune response, psychological and neurogenic disturbances as well as physiological and behavioral alterations (DE ALMEIDA et al, 2013).…”