Neurobiology of physical exercise

Project Manager
Andrew S. Naylor, PhD

Project Group
Peter Smith, MSc
Martina Hermansson, MSc

Project Outline

Brain injury in the newborn and young brain can lead to several neurological disorders that debilitate function and decrease quality of life. These injuries can occur during key developmental stages of the brain. We are primarily focused on two types of injury in the developing brain.

1). Radiation therapy is an important treatment for primary or metastatic tumours located close to or within the central nervous system in children. Improved survival rates and the longevity of juvenile cancer patients (approx. 75% of all children with a malignant disease) after their intensive treatments now reveal not only acute side-effects but also debilitating late effects of radiation therapy on intelligence, growth and puberty. These effects have been linked to hyperactivity and cognitive impairments in children and recent data suggests there is a strong correlation between the irradiation-induced cognitive dysfunction and the damage seen in the population of stem cells required for ongoing new brain cell birth, neurogenesis.

2). Early life stress and inflammation in the developing brain has effects on sensitizing the immune system and HPA axis, which in turn can have large effects on cognition and depressive and anxiety like disorders in later life. The evidence suggests that inflammation is a key mechanism of injury in the developing brain. Understanding the role of the immune system and inflammation together with the HPA axis will allow us to gain greater understanding of the cellular mechanisms and functional changes that occur in the brain in response to early life stress producing life-long effects.

Approach

Our overriding approach is to use physical exercise as a behavioural modulator for structural and functional changes in the brain. In humans, exercise has been shown to improve cognitive function and reduce the onset and progression of dementia. In addition, improved cognitive function has been tentatively correlated to the effects of exercise on neurogenesis in the hippocampus in humans. Challenges to the brain are well met by the stimulatory actions of exercise and there is now overwhelming evidence that regular exercise improves cognitive function. Therefore, it is reasonable to assume that physical activity may form an integral part of many rehabilitation and prevention programs in the future. Understanding the neurobiological basis of the effect of exercise on brain repair and rehabilitation will allow us to mitigate brain injury and improve quality of life in young survivors.