Department of Psychiatry and Behavioral Neurosciences, School of Medicine, Wayne State University, Detroit, Michigan, USA.
Department of Psychology, Washington State University, Pullman, Washington, USA.
Cannabis Cannabinoid Res. 2022 Aug;7(4):388-408. doi: 10.1089/can.2021.0113. Epub 2021 Dec 3.
The endocannabinoid (eCB) system plays a key role in maintaining homeostasis, including the regulation of metabolism and stress responses. Chronic stress may blunt eCB signaling, and disruptions in eCB signaling have been linked to stress-related psychiatric disorders and physical health conditions, including anxiety, depression, post-traumatic stress disorder (PTSD), diabetes, and obesity. Pharmacological and nonpharmacological behavioral interventions (e.g., exercise) that target the eCB system may be promising therapeutic approaches for the prevention and treatment of stress-related diseases. In this study, we perform a systematic review and the first meta-analysis to examine the impact of exercise on circulating eCB concentrations. We performed a review of the MEDLINE (PubMed) database for original articles examining the impact of exercise on eCBs in humans and animal models. A total of 262 articles were screened for initial inclusion. Thirty-three articles (reporting on 57 samples) were included in the systematic review and 10 were included in the meta-analysis. The majority of samples that measured anandamide (AEA) showed a significant increase in AEA concentrations following acute exercise (74.4%), whereas effects on 2-arachidonoylglycerol (2-AG) were inconsistent. The meta-analysis, however, revealed a consistent increase in both AEA and 2-AG following acute exercise across modalities (e.g., running, cycling), species (e.g., humans, mice), and in those with and without pre-existing health conditions (e.g., PTSD, depression). There was substantial heterogeneity in the magnitude of the effect across studies, which may relate to exercise intensity, physical fitness, timing of measurement, and/or fasted state. Effects of chronic exercise were inconsistent. Potential interpretations and implications of exercise-induced mobilization of eCBs are discussed, including refilling of energy stores and mediating analgesic and mood elevating effects of exercise. We also offer recommendations for future work and discuss therapeutic implications for exercise in the prevention and treatment of stress-related psychopathology.
内源性大麻素（eCB）系统在维持体内平衡方面发挥着关键作用，包括代谢和应激反应的调节。慢性应激可能会削弱 eCB 信号，而 eCB 信号的中断与应激相关的精神障碍和身体健康状况有关，包括焦虑、抑郁、创伤后应激障碍（PTSD）、糖尿病和肥胖症。针对 eCB 系统的药理学和非药理学行为干预（例如，运动）可能是预防和治疗应激相关疾病的有前途的治疗方法。在这项研究中，我们进行了系统评价和首次荟萃分析，以检查运动对循环 eCB 浓度的影响。我们对 MEDLINE（PubMed）数据库进行了审查，以查找研究运动对人类和动物模型中 eCB 影响的原始文章。共筛选了 262 篇文章以进行初步纳入。系统评价共纳入 33 篇文章（报告了 57 个样本），荟萃分析纳入了 10 篇文章。大多数测量花生四烯酸乙醇胺（AEA）的样本在急性运动后显示 AEA 浓度显著增加（74.4%），而对 2-花生四烯酸甘油（2-AG）的影响则不一致。然而，荟萃分析显示，在不同的运动方式（例如跑步、骑自行车）、不同物种（例如人类、老鼠）以及存在或不存在预先存在的健康状况（例如 PTSD、抑郁症）的情况下，急性运动后 AEA 和 2-AG 的浓度均一致增加。研究之间的效应大小存在很大的异质性，这可能与运动强度、身体健康状况、测量时间和/或空腹状态有关。慢性运动的影响不一致。讨论了运动诱导的 eCB 动员的潜在解释和意义，包括能量储存的补充以及介导运动的镇痛和情绪提升作用。我们还为未来的工作提出了建议，并讨论了运动在预防和治疗应激相关精神病理学方面的治疗意义。
