The Effects of Yoga on Brain GABA Levels

描述（由申请人提供）：随着瑜伽等补充和替代医学（CAM）技术的使用增加，阐明瑜伽发挥其健康作用的机制是很重要的。这项研究利用磁共振波谱（MRS）评估了为期12周的瑜伽干预对大脑主要抑制性神经递质γ氨基丁酸（GABA）水平的影响。使用MRS， GABA水平在抑郁、焦虑、癫痫、可卡因依赖和酒精依赖的受试者中被证明是低的。所有这些疾病都用已知能增加GABA系统活性的药物治疗。对照研究表明，练习瑜伽还能减轻抑郁、焦虑和癫痫的症状。在之前的一项使用MRS的研究中，经验丰富的瑜伽练习者在进行60分钟的瑜伽练习后，大脑中GABA的水平增加了27%。在60分钟的阅读后，控制组发现了0.001%的变化。这表明瑜伽可以增加大脑GABA水平，因此应该作为一种治疗干预手段来探索大脑GABA水平低的疾病。本申请提出了一项对60名受试者的纵向研究，这些受试者将被随机分为瑜伽组或阅读组。每一组都将参加为期12周的干预，其中包括60分钟的艾扬格瑜伽或每周三次阅读，最多进行36次干预。情绪量表将在每次会议开始和结束时收集。个体还将参加三个成像会议，包括情绪量表，随后在以下时间进行核磁共振扫描：随机化前基线扫描1；经过12周的瑜伽或阅读干预后的扫描2；扫描3在扫描2后大约一小时，在此期间，受试者将根据小组任务参加60分钟的瑜伽或阅读课程。本研究将探讨以下假设：1)瑜伽组和阅读组在扫描1时的基线GABA水平没有差异；2)与阅读组相比，瑜伽组的大脑GABA水平较基线有更大的增加（扫描2 -扫描1）；3)与阅读组相比，瑜伽组在脑内干预后GABA水平会出现更大的急性升高（扫描3 -扫描2）；4&5)在为期12周的干预过程中，与阅读组相比，瑜伽组的情绪改善幅度更大；6)与阅读组相比，瑜伽组的情绪量表（Post-Pre）的急性变化更大；7)情绪状态的改善与大脑GABA水平的升高呈正相关。

DESCRIPTION (provided by applicant): As use of complementary and alternative medicine (CAM) techniques such as yoga increases, it is important that the mechanisms through which yoga exerts its salubrious effects are elucidated. This study assesses the effects of a 12-week yoga intervention on the level of the brain's primary inhibitory neurotransmitter, gamma amino-butyric acid (GABA), using magnetic resonance spectroscopy (MRS). Using MRS, GABA levels have been shown to be low in subjects with depression, anxiety, epilepsy, cocaine dependence, and alcohol dependence. All of these disorders are treated with pharmacologic agents known to increase the activity of the GABA system. Controlled studies have shown that the practice of yoga also decreases symptoms in depression, anxiety, and epilepsy. In a previous study using MRS, experienced yoga practitioners demonstrated a 27% increase in brain GABA levels following a 60-minute yoga session in contrast with a .001% change found in controls after a 60-minute reading session. This suggests that yoga increases brain GABA levels, and should therefore be explored as a therapeutic intervention in disorders in which brain GABA levels are low. This application proposes a longitudinal study of 60 subjects that will be randomized into a yoga group or a reading group. Each group will participate in a 12-week intervention that will be composed of 60- minutes of Iyengar yoga or reading three times a week for a maximum of 36 interventions. Mood scales will be collected at the beginning and end of each session. Individuals will also participate in three imaging sessions comprised of mood scales followed by a MRS scan at the following times: Scan 1 at baseline prior to randomization; Scan 2 after 12-weeks of either a yoga or reading intervention; Scan 3 approximately one hour after Scan 2 during which time subjects will participate in either a 60-minute yoga or reading session depending on the group assignment. This study will explore the following hypotheses: 1) There will be no difference in baseline GABA levels at Scan 1 between the yoga group and the reading group; 2) The yoga group will exhibit a greater increase in brain GABA levels from baseline than the reading group (Scan 2 - Scan 1); 3) The yoga group will exhibit a greater acute increase in GABA levels after the intrascan intervention than the reading group (Scan 3 - Scan 2); 4&5) Pre and Post session mood scales will show greater improvement in mood over the course of the 12-week intervention in the yoga group compared to the reading group; 6) Acute changes in mood scales (Post-Pre) will be greater in the yoga group compared to the reading group; 7) Improvement in mood states and increases in brain GABA levels will be positively correlated. Public Health Relevance: Disorders associated with low brain GABA states such as depression, and anxiety, cost the U.S billions of dollars each year in treatment costs and loss of productivity, not to mention the personal costs to the individual. This study will test the hypothesis that the practice of yoga significantly increases brain GABA levels. If confirmed this would suggest that the risk-to-benefit ratio of exploring the efficacy of yoga as a treatment for low GABA states is excellent, in that the practice of yoga promotes general health, has few side effects if practiced correctly and has no risk of secondary dependencies, which often occur with some pharmacologic treatments.