Department of Psychiatry, Beth-Israel Deaconess Medical Center, Boston, MA, USA.
Transl Psychiatry. 2012 Sep 11;2(9):e160. doi: 10.1038/tp.2012.84.
Several lines of evidence implicate dysfunction in brain energy production as a key component of bipolar disorder. In particular, elevated brain lactate levels observed in this condition suggest a shift from aerobic to anaerobic metabolism, possibly as a result of mitochondrial abnormalities. Most prior imaging studies of brain metabolites were performed in either euthymic or depressed bipolar patients or compared different populations in different mood states. We sought to measure brain metabolite concentrations in the same patients in both manic and euthymic states. Given the dramatic changes in clinical state of bipolar disorder patients, we hypothesized that previously observed abnormalities in lactate concentrations in bipolar disorder might show state dependent changes. In this study 15 patients (mean age 36.1 years) diagnosed with bipolar I disorder underwent proton magnetic resonance spectroscopy of the anterior cingulate cortex and parieto-occipital cortex during hospitalization for acute mania (mean Young Mania Rating Scale (YMRS) 22.1). Seven of these subjects returned (mean interval 21.16 months) to have imaging repeated while euthymic (mean YMRS 2.0). A group of age- and gender-matched control participants (N=6) were scanned as well. We report that during mania, bipolar disorder subjects had lactate levels comparable to healthy control subjects but during euthymia these levels were significantly reduced. No significant change was observed for other metabolites. These results implicate mood dependent alterations in energy metabolism in the biology of bipolar disorder. Additionally, this finding has potential use as a biomarker for both evaluating novel treatments as well as diagnostic clarification between mood disorders.
有几条证据表明，大脑能量产生功能障碍是双相情感障碍的一个关键组成部分。特别是，在这种情况下观察到的脑乳酸水平升高表明有氧代谢向无氧代谢的转变，可能是由于线粒体异常所致。大多数先前关于脑代谢物的影像学研究都是在心境正常或抑郁的双相情感障碍患者中进行的，或者是比较了不同情绪状态下的不同人群。我们试图在躁狂和心境正常的同一患者中测量脑代谢物浓度。鉴于双相情感障碍患者的临床状态发生了巨大变化，我们假设先前观察到的双相情感障碍患者乳酸浓度异常可能会出现与状态相关的变化。在这项研究中，15 名（平均年龄 36.1 岁）被诊断为 I 型双相情感障碍的患者在急性躁狂住院期间接受了前扣带皮层和顶枕叶皮层的质子磁共振波谱检查（平均 Young Mania Rating Scale (YMRS) 22.1）。其中 7 名患者（平均间隔 21.16 个月）在心境正常时返回进行重复成像（平均 YMRS 2.0）。一组年龄和性别匹配的对照组（N=6）也进行了扫描。我们报告说，在躁狂期间，双相情感障碍患者的乳酸水平与健康对照组相当，但在心境正常时，这些水平显著降低。其他代谢物没有观察到显著变化。这些结果表明，双相情感障碍的生物学中存在与情绪相关的能量代谢改变。此外，这一发现有可能作为评估新型治疗方法的生物标志物，以及在情绪障碍之间进行诊断澄清。
