Robillard Rébecca, Lagopoulos Jim, Hermens Daniel F, Naismith Sharon L, Rogers Naomi L, White Django, Carpenter Joanne S, Kaur Manreena, Scott Elizabeth M, Hickie Ian B
Institute of Mental Health ResearchOttawa, ONT, Canada.
Sunshine Coast Mind and Neuroscience, Thompson Institute, University of the Sunshine CoastBirtinya, QLD, Australia.
Front Neurosci. 2017 Jun 20;11:336. doi: 10.3389/fnins.2017.00336. eCollection 2017.
Myo-inositol, a second messenger glucose isomer and glial marker, is potentiated by melatonin. In addition to common abnormalities in melatonin regulation, depressive disorders have been associated with reduced myo-inositol in frontal structures. This study examined associations between myo-inositol in the anterior cingulate cortex and the timing of evening melatonin release. Forty young persons with unipolar depression were recruited from specialized mental health services (20.3 ± 3.8 years old). Healthy controls were recruited from the community (21.7 ± 2.6 years old). The timing of dim light melatonin onset (DLMO) was estimated using salivary melatonin sampling. Myo-inositol concentrations (MI/CrPCr ratio) in the anterior cingulate cortex were obtained using proton magnetic resonance spectroscopy. After controlling for age, sex, and CrPCr concentration the depression group had significantly lower MI/CrPCr ratios than healthy controls [ = 11.4, = 0.001]. In the depression group, later DLMO correlated with lower MI/CrPCr ratio ( = -0.48, = 0.014). These findings suggest that neurochemical changes in the frontal cortex are associated with circadian disruptions in young persons with depression.
肌醇是一种第二信使葡萄糖异构体和神经胶质标志物，褪黑素可增强其作用。除了褪黑素调节方面的常见异常外，抑郁症还与额叶结构中肌醇减少有关。本研究调查了前扣带回皮质中肌醇与夜间褪黑素释放时间之间的关联。从专业心理健康服务机构招募了40名单相抑郁症青年患者（年龄20.3±3.8岁）。从社区招募了健康对照者（年龄21.7±2.6岁）。通过唾液褪黑素采样估计暗光褪黑素起始（DLMO）时间。使用质子磁共振波谱法获得前扣带回皮质中的肌醇浓度（MI/CrPCr比值）。在控制了年龄、性别和CrPCr浓度后，抑郁症组的MI/CrPCr比值显著低于健康对照组[ = 11.4， = 0.001]。在抑郁症组中，较晚的DLMO与较低的MI/CrPCr比值相关（ = -0.48， = 0.014）。这些发现表明，额叶皮质中的神经化学变化与抑郁症青年患者的昼夜节律紊乱有关。
