The complex role of regular exercise on brain function
Regular exercise has systemic beneficial effects, including the promotion of brain function. The adaptive response to regular exercise involves the up-regulation of the enzymatic antioxidant system and modulation of oxidative damage. Reactive oxygen species (ROS) are important regulators of cell signaling. Exercise, via intensity- dependent modulation of metabolism and/or directly activated ROS generating enzymes, modulates the cellular redox state of the brain. ROS mediated alteration of lipids, protein, and DNA could directly affect brain function, while exercise modulates the accumulation of oxidative damage. Oxidative alteration of macromolecules can activate signaling processes, membrane remodeling, and gene transcription. ROS are also involved in the self-renewal and differentiation of neuronal stem cells and the exercise-mediated neurogenesis could be partly associated with ROS production. Exercise directly activates brain derived neurotrophic factor, neuron growth factor and vascular endothelial growth factor which play an important role in synaptic plasticity, memory and neurogenesis. Moreover, regular exercise can change the bacterial content and activity of microbiome, which might have an effect of brain function and the prevention of neurodegenerative diseases. Overall, regular exercise physical exercise has neuroprotective role with wide range of signaling molecular pathways.