Promoting Neuroplasticity for Motor Rehabilitation After Stroke: Considering the Effects of Aerobic Exercise and Genetic Variation on Brain-Derived Neurotrophic Factor

Abstract

Recovery of motor function after stroke involves relearning motor skills and is mediated by neuroplasticity. Recent research has focused on developing rehabilitation strategies that facilitate such neuroplasticity to maximize functional outcome poststroke. Although many molecular signaling pathways are involved, brain-derived neurotrophic factor (BDNF) has emerged as a key facilitator of neuroplasticity involved in motor learning and rehabilitation after stroke. Thus, rehabilitation strategies that optimize BDNF effects on neuroplasticity may be especially effective for improving motor function poststroke. Two potential poststroke rehabilitation strategies that consider the importance of BDNF are the use of aerobic exercise to enhance brain function and the incorporation of genetic information to individualize therapy. Converging evidence demonstrates that aerobic exercise increases BDNF production and consequently enhances learning and memory processes. Nevertheless, a common genetic variant reduces activity-dependent secretion of the BDNF protein. Thus, BDNF gene variation may affect response to motor rehabilitation training and potentially modulate the effects of aerobic exercise on neuroplasticity. This perspective article discusses evidence that aerobic exercise promotes neuroplasticity by increasing BDNF production and considers how aerobic exercise may facilitate the acquisition and retention of motor skills for poststroke rehabilitation. Next, the impact of the BDNF gene val66met polymorphism on motor learning and response to rehabilitation is explored. It is concluded that the effects of aerobic exercise on BDNF and motor learning may be better exploited if aerobic exercise is paired more closely in time with motor training. Additionally, information about BDNF genotype could provide insight into the type and magnitude of effects that aerobic exercise may have across individuals and potentially help guide an individualized prescription of aerobic exercise to enhance motor rehabilitation poststroke.

Moving rehabilitation research forward: Developing consensus statements for rehabilitation and recovery research

“…23 Individuals' genetic profiles may also influence recovery. [24][25][26] While interest has centred on genes known to contribute to neuroplasticity, 27 there are a number of candidate biomarkers to consider as well as gene-gene interactions and epigenetics.…”

Forced Aerobic Exercise Enhances Motor Recovery After Stroke: A Case Report

“…It is well accepted that motor recovery after stroke is achieved through cortical reorganization, in which the brain and central nervous system (CNS) adapt in response to environmental and behavioral change to acquire novel information by modifying neural connectivity and function (Knaepen, Goekint, Heyman, & Meeusen, 2010;Mang, Campbell, Ross, & Boyd, 2013). Although the exact mechanism for cortical reorganization is not known, neurotrophins are thought to play a major role by enabling neuronal survival, potentiation, and differentiation; promoting dendritic growth and remodeling; and promoting synaptic plasticity (Lin & Kuo, 2013;Voss, Nagamatsu, Liu-Ambrose, & Kramer, 2011).…”

“…The activity-dependent changes in the CNS and elevation of BDNF levels after acute bouts of aerobic exercise provide a theoretical rationale for exploiting the potential neurophysiologic effects of aerobic exercise as a means to promote motor recovery after stroke (Mang et al, 2013). Therefore, we developed a model to integrate aerobic exercise with task practice in an attempt to optimize motor recovery.…”

“…In people with stroke, aerobic exercise may serve to prime the CNS and, if paired with wellselected motor training, has the potential to facilitate neuroplastic changes (Mang et al, 2013). Motor training tasks must be appropriately selected to be meaningful, intense, and task specific to create changes in the CNS (Bayona, Bitensky, Salter, & Teasell, 2005;Wolf, Blanton, Baer, Breshears, & Butler, 2002).…”

No Change in Brain-Derived Neurotrophic Factor Levels Following a Single Session of Light to-Moderate Intensity Walk in Chronic Stroke Patients

“…However, it is not known whether the conventional gait training widely used in clinical physical therapy practice is able to induce changes in serum levels of brain-derived neurotrophic factor (BDNF), which could positively influence neurophysiological mechanisms. Studies have shown that acute and chronic exercises increase peripheral levels of BDNF, mainly after performing aerobic exercise [12][13][14][15][16]. Additionally, BDNF levels in the central nervous system are positively associated with peripheral BDNF levels, particularly serum and plasma, and therefore, circulating peripheral BDNF level has been suggested as a good biomarker for concentration brain this neurotrophin [17].…”