Levels of interlukin-2, interlukin-6 and its soluble receptors in the first episode depression of Uygur patients before and after treatment with venlafaxine

Abstract

Objective To investigate the action of interlukin-2(IL-2), interlukin-6(IL-6) and its soluble receptors(sIL-2R, sIL-6R) in the first episode of depression in the patients of Uyghur nationality and the differences in IL-2, IL-6 and sIL-2R, sIL-6R levels between the responsive depressed patients and the refractory depressed patients treated with venlafaxine. Methods A case-control study design was conducted.57 first-episode patients with depression (patient group) and 55 healthy people matched with gender and age (control group) were recruited in the study.An intervention with sustained-releasing venlafaxine tablets at fixed dose of 150 mg/d was performed in the patient group.The severity of the illness was evaluated by using the Hamilton's depression scale (HAMD-17) before and after the therapy.And by calculating the reduction rate of HAMD-17 (≥ 50% or <50%), the patients were divided into the responsive or refractory groups.The serum levels of IL-2, IL-6, sIL-2R and sIL-6R in patients and controls were tested by ELISA, and a re-test was done with the patients after treatment. Results There were statistical significant differences of the levels of serum IL-2, IL-6 and sIL-2R, sIL-6R between the patients and the control group (P 0.05). There were positive correlations between HAMD, serum IL-2(r=0.677; P=0.000) and IL-6(r=0.197; P=0.033)before treatment in all patients. Conclusion Serum IL-2 and IL-6 may play a role in the onset of the depression.The efficacy of venlafaxine is negatively correlated with the levels of serum IL-2 and IL-6.Regulating the imbalanced inflammatory cytokines and the immune system may be one of the mechanisms of drug therapy of depression. Key words: Depression; Antidepressant; Interleukin-2; Interleukin-6