Section of Endocrinology, Diabetes, Nutrition, and Weight Management, Boston University School of Medicine (BUSM), Boston, MA, USA.
Framingham Heart Study, Framingham, MA, USA.
J Alzheimers Dis. 2022;85(2):805-814. doi: 10.3233/JAD-215109.
One of the mechanisms suggested to link physical activity (PA) to favorable brain health is through stimulation of neural growth factors such as brain-derived neurotrophic factor (BDNF). Acute bouts of PA stimulate circulating BDNF levels.
In this investigation, we assessed whether habitual, accelerometer-measured PA levels were related to circulating BDNF levels in a middle-aged cohort.
In the Framingham Heart Study Third Generation cohort, 1,769 participants provided reliable accelerometry data and were not missing BDNF measurement or platelet counts. In a cross-sectional analysis, using multivariable regression, we related PA measures to serum BDNF levels, adjusting for age, sex, smoking status, platelet count, depression status, and accelerometer wear time.
Our study participants (mean age 47±9 years, 50.8% women) spent an average of 22.3 mins/day in moderate-to-vigorous (MV)PA. Most PA variables (steps, MVPA, light activity, and sedentary time) were not related to BDNF levels (p > 0.05). We observed a non-linear trend, where 15-50 mins/week vigorous activity was associated with lower BDNF compared to those with 0 min vigorous activity (β= -0.049±0.024, p = 0.05), but with no significant associations at lower or higher vigorous activity levels. In smokers, MVPA was also associated with lower BDNF levels (β= -0.216±0.079, p = 0.01).
Our study reveals that circulating BDNF is not chronically elevated in individuals with higher levels of habitual PA in middle-aged adults from the community and may even be chronically suppressed with higher PA in subgroups, including current smokers. These results do not contradict previous studies demonstrating that circulating BDNF rises acutely after PA.
有研究提出，体力活动（PA）通过刺激神经营养因子（如脑源性神经营养因子，BDNF）与良好的大脑健康相关联。急性 PA 可刺激循环 BDNF 水平升高。
本研究旨在评估中年人群中，习惯性、加速度计测量的 PA 水平与循环 BDNF 水平之间的关系。
在弗雷明汉心脏研究第三代队列中，1769 名参与者提供了可靠的加速度计数据，且未缺失 BDNF 测量值或血小板计数。在横断面分析中，我们采用多元回归方法，在校正年龄、性别、吸烟状况、血小板计数、抑郁状态和加速度计佩戴时间后，将 PA 测量值与血清 BDNF 水平相关联。
本研究参与者（平均年龄 47±9 岁，50.8%为女性）平均每天进行 22.3 分钟中度至剧烈体力活动（MVPA）。大多数 PA 变量（步数、MVPA、轻体力活动和久坐时间）与 BDNF 水平无关（p＞0.05）。我们观察到一种非线性趋势，即每周 15-50 分钟剧烈活动与 BDNF 水平较低相关，与不进行剧烈活动相比（β=-0.049±0.024，p=0.05），但在较低或较高剧烈活动水平时则没有显著相关性。在吸烟者中，MVPA 也与较低的 BDNF 水平相关（β=-0.216±0.079，p=0.01）。
本研究表明，在社区中年成年人中，习惯性较高 PA 水平的个体循环 BDNF 并未持续升高，甚至在包括当前吸烟者在内的亚组中，较高的 PA 水平可能会导致 BDNF 持续受到抑制。这些结果与之前的研究结果并不矛盾，即 PA 后循环 BDNF 水平会急性升高。
