Institute of Respiratory and Critical Care, the First Hospital of China Medical University, Shenyang, China.
Restor Neurol Neurosci. 2021;39(3):159-171. doi: 10.3233/RNN-201060.
Physical exercise can improve cognitive dysfunction. Its specific mechanism remains unknown. Recent studies have indicated that elevating or peripherally overexpressing brain-derived neurotrophic factors (BDNF) improve cognitive impairment.
This meta-analysis aimed to investigate whether physical exercise improves cognitive performance in patients with cognitive dysfunction, such as mild cognitive impairment (MCI) or Alzheimer's disease (AD), by increasing peripheral BDNF.
PubMed, Embase, Cochrane Library, and Web of Science were searched up to June 2020 for studies that assayed the changes in peripheral BDNF levels in MCI and AD patients after exercise training.
Peripheral BDNF levels were significantly elevated after a single exercise session (SMD = 0.469, 95% CI: 0.150-0.787, P = 0.004) or regular exercise interventions (SMD = 0.418, 95% CI: 0.105-0.731, P = 0.009). Subgroup analysis showed that only regular aerobic exercise interventions (SMD = 0.543, 95% CI: 0.038-1.049, P = 0.035) and intervention duration of 16 weeks or greater (SMD = 0.443, 95% CI: 0.154 -0.733, P = 0.003) significantly increased peripheral BDNF levels. Only plasma BDNF levels (SMD = 0.365, 95% CI:0.066-0.664, P = 0.017) were significantly increased after exercise interventions.
Acute and chronic physical exercises may improve cognitive impairment by increasing peripheral BDNF levels. Aerobic exercises and a longer duration of exercising increased BDNF levels. These findings also suggest that BDNF may be a suitable biomarker for evaluating the effect of exercise in patients with cognitive impairment, such as AD or MCI.
体育锻炼可以改善认知功能障碍。其具体机制尚不清楚。最近的研究表明，提高或外周过表达脑源性神经营养因子（BDNF）可以改善认知障碍。
本荟萃分析旨在探讨体育锻炼是否可以通过增加外周 BDNF 来改善认知功能障碍患者（如轻度认知障碍（MCI）或阿尔茨海默病（AD））的认知表现。
截至 2020 年 6 月，我们在 PubMed、Embase、Cochrane 图书馆和 Web of Science 上检索了评估运动训练后 MCI 和 AD 患者外周 BDNF 水平变化的研究。
单次运动后外周 BDNF 水平显著升高（SMD=0.469，95%CI：0.150-0.787，P=0.004）或定期运动干预（SMD=0.418，95%CI：0.105-0.731，P=0.009）。亚组分析显示，只有定期有氧运动干预（SMD=0.543，95%CI：0.038-1.049，P=0.035）和干预持续时间为 16 周或更长时间（SMD=0.443，95%CI：0.154-0.733，P=0.003）可显著升高外周 BDNF 水平。只有运动干预后血浆 BDNF 水平（SMD=0.365，95%CI：0.066-0.664，P=0.017）显著升高。
急性和慢性运动锻炼可以通过增加外周 BDNF 水平来改善认知障碍。有氧运动和更长的运动时间增加了 BDNF 水平。这些发现还表明，BDNF 可能是评估运动对认知障碍（如 AD 或 MCI）患者影响的合适生物标志物。
