Does a single bout of exercise impacts BDNF, oxidative stress and epigenetic markers in spinal cord injury patients?

Our aim was to evaluate the impact of a single bout of exercise, consisting of a gait training session with body weight support (BWS), on histone acetylation status (global histone H4 and H3 acetylation levels), brain-derived neurotrophic factor (BDNF) levels, and oxidative stress markers in peripheral blood of individuals with chronic spinal cord injury (SCI). We also set out to compare these responses with those recorded after gait training performed using a walker and with no BWS. The subjects (nearly all with an incomplete spinal cord lesion) were each submitted to two 60-minute experimental sessions on separate days with a 1- week wash-out period between the interventions. The order of the sessions was randomized. Blood samples were collected before and after each experimental trial for measurement of biomarkers. The histone acetylation status and BDNF levels remained unchanged after both interventions. After the treadmill training, the participants showed a strong increase in levels of oxidative stress markers [plasma advanced oxidation protein products (AOPPs), nitrite and thiobarbituric acid-reactive substances] without changes in antioxidant mediators. Instead, elevations in AOPP and nitrite concentrations, in addition to increased levels of glutathione and catalase activity, were found after the walker training. A single bout of gait training, be it conducted on a treadmill with BWS or using a walker without BWS, is not able to alter BDNF levels and histone acetylation status in SCI patients. However, these trials can modulate oxidative stress parameters, seemingly in a protocol-dependent manner.