Exercise Duration Differentially Effects Age-related Neuroinflammation and Hippocampal Neurogenesis

Short-Term, Voluntary Exercise Affects Morpho-Functional Maturation of Adult-Generated Neurons in Rat Hippocampus

“…In conclusion, other authors have reported beneficial effects of short-term exercise on neurogenesis processes [ 71 , 72 ], but in our study, we demonstrate not only that the morpho-functional changes induced by exercise on very immature adult-generated neurons are permanent, being detected far from the end of exercise, but also that exercise changes timing and kind of morpho-functional development occurring in the period of time subsequent the end of exercise. Therefore, the present findings contribute to increasing the body of information on exercise-induced changes and underpinning the beneficial potential of physical activity on brain health, also when it is performed for short times.…”

Sex and BDNF Val66Met Polymorphism matter for exercise-induced increase in neurogenesis and cognition in middle-aged mice

“…The findings that AT increased neurogenesis in the ventral hippocampus is interesting because it is the region that has more connections with the PFC and plays a pivotal role in inhibitory processes and emotional regulation (Adhikari et al, 2010; Chen et al, 2018). Also, although physical exercise increases the number of new neurons in the hippocampus (Gualtieri et al, 2017); Connolly et al, 2022), the effects on depressive and anxious-like behavior in middle-aged subjects are ambiguous (Morgan et al, 2018; Chaiton et al, 2019). Indeed, Chaiton et al (2019) used female middle-aged mice and found that increased neurogenesis was not linked to changes in depressive-like behaviour.…”

“…Intriguingly, adult hippocampal neurogenesis decreases with age, is impaired in AD, and increases with exercise. In rodents, exercise increases the expression of doublecortin (DCX), a protein expressed in immature neurons (Brown et al, 2003) in both young (Fuss et al, 2010; Segal-Gavish et al, 2019) and aged male mice (Connolly et al, 2022), and young female mice (Kim et al, 2017; Segal-Gavish et al, 2019), suggesting that exercise increases new neurons. Moreover, hippocampal neurogenesis promotes cognitive flexibility, and is modulated by both sex and BDNF levels (Anacker and Hen, 2017; Berdugo-Vega et al, 2021; Choi et al, 2018; Kuhn et al, 1996; Marrocco et al, 2017; Mu and Gage, 2011; van Praag et al, 1999; Yagi and Galea, 2019).…”

Exercise‐induced modulation of neuroinflammation in ageing

“…However, as excellently reviewed and discussed elsewhere (Duggal et al, 2019), the modern sedentary lifestyle is an inevitable contributor to gradual immune dysfunction in ageing as it is inconsistent with evolutionary adaptive biological processes. While ageing results in inflammation and cytokine imbalance in the CNS of rodents housed with no access to exercise, endurance running reverses these effects (Connolly et al, 2022;Dallagnol et al, 2017;Gomes da Silva et al, 2013;Lovatel et al, 2013;Mela et al, 2020), resulting in amelioration of memory impairments. Alterations in hippocampal cytokine expression display J Physiol 601.11 a 'dose response' to exercise (Connolly et al, 2022), but even a short duration (less than two weeks) of 30 min of daily low-intensity treadmill exercise can favourably shift the ratio of pro-to anti-inflammatory cytokines in the hippocampus of aged rats (Gomes da Silva et al, 2013), suggesting that even short-term improvements to a sedentary lifestyle can yield positive benefits to the brain.…”

“…While ageing results in inflammation and cytokine imbalance in the CNS of rodents housed with no access to exercise, endurance running reverses these effects (Connolly et al, 2022;Dallagnol et al, 2017;Gomes da Silva et al, 2013;Lovatel et al, 2013;Mela et al, 2020), resulting in amelioration of memory impairments. Alterations in hippocampal cytokine expression display J Physiol 601.11 a 'dose response' to exercise (Connolly et al, 2022), but even a short duration (less than two weeks) of 30 min of daily low-intensity treadmill exercise can favourably shift the ratio of pro-to anti-inflammatory cytokines in the hippocampus of aged rats (Gomes da Silva et al, 2013), suggesting that even short-term improvements to a sedentary lifestyle can yield positive benefits to the brain. Given their central role in neuroimmune function, attention has focused on how glia may mediate at least some of these effects of exercise on the brain.…”