Combined exercise training-induced improvements in executive functions are related to baseline plasmatic levels of Brain-Derived Neurotrophic Factor (BDNF) in middle-aged adults and older with Type 2 Diabetes Mellitus

Abstract

Background: Type 2 Diabetes Mellitus (T2DM) affects many cognitive functions and aerobic plus resistance exercise training, named combined training (CT), by improving metabolic control may mitigate or reverse the cognitive impairment T2DM-related. Brain-derived neurotrophic factor (BDNF) plays a substantial role in cognitive functions. However, the effects of CT on BDNF levels of T2DM subjects are poorly known.Aim: This study analyzed the effects of 8 weeks of CT on circulating BDNF levels and assessed whether plasmatic BDNF levels were related to CT-induced improvements in executive functions and long-term memory of T2DM subjects.Methods: Thirty-five (63 ± 8 years old) T2DM subjects of both sexes entered into CT (n = 17, thrice-weekly during 8 weeks) or control group (CONT, n = 18). Executive functions (measured through Trail making test, Stroop color task, and Digit Span), long-term memory (measured through the simplified version of Taylor Complex Figure Test), and blood samples were evaluated pre- and post-intervention.Results: Pre-CT plasma BDNF levels were positively related to CT-induced improvements on executive functions composite z-score (r = 0.71), inhibitory control (r = 0.58) and cognitive flexibility (r = 0.56), but not to long-term memory. Plasma BDNF levels were not statistically changed (pre-CT: 179 ± 88 pg/ml; post-CT: 148 ± 108 pg/ml; pre-CONT: 163 ± 71 pg/ml; post-CONT: 141 ± 84 pg/ml, p > 0.05).Conclusion: Higher pre-training BDNF levels might be a potentializing factor of the training-induced improvements on executive functions, independently of the training-alterations in resting BDNF levels of T2DM subjects.

Exercise improves depression through positive modulation of brain-derived neurotrophic factor (BDNF). A review based on 100 manuscripts over 20 years

“…The majority of exercise-based studies report that BDNF levels following acute exercise return to baseline values 15–60 min post-exercise cessation, although two studies found significantly lower BDNF concentrations during rest of 2–3 h when compared to basal BDNF values ( Castellano and White, 2008 ; Yarrow et al, 2010 ). In fact, a recent 9-week exercise study found that higher pre-exercise BDNF levels were indeed found to be a significant factor involved with the exercise-induced improvements related to frontal lobe function, but was independent of the exercise-induced alterations in resting peripheral BDNF levels, implying that exercise is able to induce improvements in frontal lobe function but not in inducing long-term changes in the peripheral BDNF ( da Silveira-Rodrigues et al, 2021 ). Could this rapid return to baseline values indicate re-uptake by the brain to exert BDNF’s neuroplastic effects?…”