Clinic of Psychiatry, Clinical Centre of Serbia, Pasterova 2, 11000 Belgrade, Serbia.
Prog Neuropsychopharmacol Biol Psychiatry. 2013 Jun 3;43:1-6. doi: 10.1016/j.pnpbp.2012.11.009. Epub 2012 Nov 28.
Growing scientific evidence indicates that there is a correlation between depression and alternations in the immune system. The main aim of the study was to investigate serum levels of Interleukin-6 (IL-6) and Tumour Necrosis Factor-alpha (TNF-α) in melancholic and atypical depressive patients during acute exacerbations of illness, compared to healthy subjects. The secondary aim was to explore a possible association between cytokine levels and clinical characteristics, as well as total duration of prior antidepressant treatment.
We measured serum levels of IL-6 and TNF-α in 47 patients suffering from major depressive disorder (MDD) (29 melancholic and 18 atypical) in exacerbation of illness, compared to 39 healthy controls, matched by sex, body mass index (BMI) and smoking habits. Serum levels of IL-6 and TNF-α were measured by enzyme-linked immunosorbent assay (ELISA). The severity of psychopathology was assessed using the Hamilton Depression Rating Scale (HDRS).
IL-6 was significantly elevated in melancholic depressive patients (MDD-M) compared to healthy controls, while no difference was found between the patients with atypical depression (MDD-A) and the healthy group. Lower TNF-α serum level was found both in melancholic and in patients with atypical depression, compared with healthy subjects. We detected a positive correlation between cytokine levels in atypical, but not in melancholic subjects. Sex, age, smoking habits and BMI were not associated to cytokine levels in neither group. Clinical parameters (duration of illness, current episode, age of onset) were related to cytokine levels in atypical depression, while the duration of lifetime exposure to antidepressant treatment correlated to IL-6 serum levels in both melancholic and atypical depression.
Our results suggest that the difference in pro-inflammatory cytokine levels could reflect a biological difference between melancholic and atypical depression. A positive correlation between the cytokines (TNF-α and IL-6) observed in depressive patients with atypical features, might be influenced by chronic course of illness, while IL-6 elevation could represent a state indicator for acute exacerbation, especially in melancholic patients. Total duration of antidepressant treatment could be a relevant factor influencing the immune status of patients who suffer either from melancholic or atypical depression.
越来越多的科学证据表明，抑郁与免疫系统的改变之间存在关联。本研究的主要目的是在疾病急性加重期间，比较单相抑郁和非典型抑郁患者与健康受试者之间血清白细胞介素-6 (IL-6) 和肿瘤坏死因子-α (TNF-α) 的水平。次要目的是探索细胞因子水平与临床特征之间以及与先前抗抑郁治疗总持续时间之间的可能关联。
我们测量了 47 名患有重度抑郁症（MDD）（29 名单相抑郁和 18 名非典型抑郁）患者在疾病急性加重期间血清 IL-6 和 TNF-α 的水平，与 39 名性别、体重指数（BMI）和吸烟习惯相匹配的健康对照组进行比较。采用酶联免疫吸附试验（ELISA）测量血清 IL-6 和 TNF-α 水平。使用汉密尔顿抑郁评定量表（HDRS）评估精神病理学的严重程度。
与健康对照组相比，单相抑郁患者（MDD-M）的 IL-6 明显升高，而非典型抑郁患者（MDD-A）与健康组之间无差异。与健康受试者相比，单相和非典型抑郁患者的 TNF-α 血清水平均较低。我们在非典型抑郁患者中检测到细胞因子水平呈正相关，但在单相抑郁患者中未检测到。在两组中，性别、年龄、吸烟习惯和 BMI 与细胞因子水平均无关。临床参数（疾病持续时间、当前发作、发病年龄）与非典型抑郁患者的细胞因子水平相关，而终生抗抑郁治疗的持续时间与单相和非典型抑郁患者的 IL-6 血清水平相关。
我们的研究结果表明，促炎细胞因子水平的差异可能反映了单相和非典型抑郁之间的生物学差异。在具有非典型特征的抑郁患者中观察到细胞因子（TNF-α 和 IL-6）之间的正相关可能受到慢性病程的影响，而 IL-6 的升高可能代表急性加重的状态指标，尤其是在单相抑郁患者中。抗抑郁治疗的总持续时间可能是影响单相或非典型抑郁患者免疫状态的一个相关因素。
