Physical exercise increases adult hippocampal neurogenesis in male rats provided it is aerobic and sustained

Abstract

Key pointsr Aerobic exercise, such as running, enhances adult hippocampal neurogenesis (AHN) in rodents. r Little is known about the effects of high-intensity interval training (HIT) or of purely anaerobic resistance training on AHN.r Here, compared with a sedentary lifestyle, we report a very modest effect of HIT and no effect of resistance training on AHN in adult male rats.r We found the most AHN in rats that were selectively bred for an innately high response to aerobic exercise that also run voluntarily and increase maximal running capacity.r Our results confirm that sustained aerobic exercise is key in improving AHN.Abstract Aerobic exercise, such as running, has positive effects on brain structure and function, such as adult hippocampal neurogenesis (AHN) and learning. Whether high-intensity interval training (HIT), referring to alternating short bouts of very intense anaerobic exercise with recovery periods, or anaerobic resistance training (RT) has similar effects on AHN is unclear. In addition, individual genetic variation in the overall response to physical exercise is likely to play a part in the effects of exercise on AHN but is less well studied. Recently, we developed polygenic rat models that gain differentially for running capacity in response to aerobic treadmill training. Here, we subjected these low-response trainer (LRT) and high-response trainer (HRT) adult male rats to various forms of physical exercise for 6-8 weeks and examined the effects on AHN. Compared with sedentary animals, the highest number of doublecortin-positive hippocampal cells was observed in HRT rats that ran voluntarily on a running wheel, whereas HIT on the treadmill had a smaller, statistically non-significant effect on AHN. Adult hippocampal neurogenesis was elevated in both LRT and HRT rats that underwent endurance training on a treadmill compared with those that performed RT by climbing a vertical ladder with weights, despite their significant gain in strength. Furthermore, RT had no effect on proliferation (Ki67), maturation (doublecortin) or survival (bromodeoxyuridine) of new adult-born hippocampal neurons in adult male Sprague-Dawley rats. Our results suggest that physical exercise promotes AHN most effectively if the exercise is aerobic and sustained, especially when accompanied by a heightened genetic predisposition for response to physical exercise. Abbreviations AHN, adult hippocampal neurogenesis; BDNF, brain-derived neurotrophic factor; BrdU, bromodeoxyuridine; HIT, high-intensity interval training; HRT, high-response trainer; LRT, low-response trainer; RW, running wheel; Sed, sedentary; TBS, Tris-buffered saline;V O2 max , maximal oxygen uptake.

Glial cells and energy balance

“…In contrast, dietary restriction results in higher levels of BDNF and neurotrophin-3 (NT-3), with an increase in neurogenesis (Lee et al 2002). In accordance with this, moderate aerobic exercise is reported to stimulate adult hippocampal neurogenesis in rodents (Nokia et al 2016), taking part in hippocampal-dependent memory, such as that needed in place conditioning (Shors et al 2001) and reinforcing synaptic connections in pre-existing neurons by changes in neural plasticity (Trejo et al 2008, LlorensMartin et al 2010. These dietary effects on hippocampal neurogenesis could possibly be involved in feeding behavior and other conductual phenomena (Stangl & Thuret 2009).…”

The rate of training response to aerobic exercise affects brain function of rats

“…Therefore, despite of the fact that the effects of exercise is systemic (Radak et al, 2008), it is appears that not just muscle type specific but organ specific differences could be present in rats with different aerobic trainability. Recently, Nokia et al provide evidence that neurogenesis in hippocampus is greater in high response to training rats compared to low response rats, and especially when the exercise is aerobic and of sustained duration (Nokia et al, 2016). Therefore, it was suggested that low and high training responders to aerobic training could have different adaptive response in cognitive brain function and molecular adaptation in hippocampus.…”

Frequently endorsed cognitive and physical activities among community-dwelling older adults

“…Moreover, recent research suggests that aerobic exercise, such as running, enhances adult hippocampal neurogenesis in rodents -especially when the aerobic exercise is sustained. Though running was not among the most frequently endorsed physical activities in our sample, it is worth bearing in mind recent neuroscientific findings on the potential benefits of specific types of activities when clinicians make activity recommendations for older adults [46].…”