Byrne Michelle L, Whittle Sarah, Allen Nicholas B
From the Department of Psychology (Byrne, Allen), The University of Oregon, Eugene, Oregon; Melbourne Neuropsychiatry Centre (Whittle), Department of Psychiatry, The University of Melbourne & Melbourne Health, Victoria, Australia; and Melbourne School of Psychological Sciences (Allen), The University of Melbourne, Victoria, Australia.
Psychosom Med. 2016 May;78(4):389-400. doi: 10.1097/PSY.0000000000000311.
Major depressive disorder and related symptoms have been shown to be associated with inflammation, and this association is likely to be mediated through changes in brain structure and function. This article provides a systematic review of studies that have used brain imaging techniques to identify neural mechanisms linking inflammation and depressive symptoms.
A systematic search of online databases identified 26 studies that fulfilled the inclusion and exclusion criteria.
In general, increased peripheral inflammation was associated with differences in function in several subcortical regions, as well as medial and ventral prefrontal regions-both at rest (7 studies) and during exposure to emotional stimuli (14 studies). Also, increased activation in some of these regions was associated with depression (18 studies). Too few studies have measured neuroinflammation markers (three) or brain structure (three), so generalizations about these mechanisms cannot yet be made.
This review supports the view that peripheral inflammation is an etiological process that may influence depression via effects on brain function. Several methodological inconsistencies in the extant literature need to be addressed, most notably a lack of formal mediational testing in longitudinal designs and inconsistencies across imaging methods and inflammation induction and measurement techniques. Further work is also required to establish the mechanisms by which basal inflammation levels influence brain function and depressive symptoms in both healthy and clinical samples.
重度抑郁症及相关症状已被证明与炎症有关，这种关联可能是通过脑结构和功能的变化介导的。本文对使用脑成像技术来确定炎症与抑郁症状之间神经机制的研究进行了系统综述。
对在线数据库进行系统检索，确定了26项符合纳入和排除标准的研究。
一般来说，外周炎症增加与几个皮质下区域以及内侧和腹侧前额叶区域的功能差异有关，无论是在静息状态（7项研究）还是在暴露于情绪刺激时（14项研究）。此外，这些区域中一些区域的激活增加与抑郁症有关（18项研究）。测量神经炎症标志物（3项）或脑结构（3项）的研究太少，因此尚无法对这些机制进行概括。
本综述支持以下观点，即外周炎症是一个病因学过程，可能通过对脑功能的影响来影响抑郁症。现有文献中存在几个方法学上的不一致之处需要解决，最明显的是纵向设计中缺乏正式的中介测试，以及成像方法、炎症诱导和测量技术之间的不一致。还需要进一步的工作来确定基础炎症水平影响健康和临床样本中脑功能和抑郁症状的机制。
