Simultaneous measurement of 23 plasma cytokines in late-life depression.

According to the cytokine hypothesis of depression, cytokines play key roles in the behavioral, neuroendocrinal, and neurochemical features of depression. In this study, we used a bioplex assay to simultaneously measure the levels of 23 plasma cytokines in 18 patients with late-life depression and 38 normal controls, and these levels were compared between the two groups. The plasma interleukin-1alpha (IL-1alpha) levels were found to be significantly different between the two groups. After adjusting for age, gender, low-density lipoprotein cholesterol, and triglyceride, the plasma IL-1alpha levels were significantly higher in the patients with late-life depression than in the normal control subjects. Thus, this study provides preliminary evidence that plasma IL-1alpha may play important roles in the pathogenesis of late-life depression.