MiR-155 is involved in major depression disorder and antidepressant treatment via targeting SIRT1.

Major depressive disorder (MDD) is a common mood disorder, and the treatment of MDD requires a variety of biopsychosocial approaches. The role of Silent information regulator 1 (SIRT1) in the regulation of MDD has recently been implicated. Here, we aimed to explore and elucidate the therapeutic effects of a microRNA, miR-155, in the treatment of MDD. With quantitative real-time PCR (qRT-PCR) analysis, we confirmed that cellular and serum levels of miR-155 were up-regulated in individuals with depression compared with those in healthy controls. TargetScan analysis indicated that SIRT1 is a target of miR-155, which was confirmed by dual-luciferase assay, qRT-PCR and Western blot analyses. Treatment of human neural progenitor cells with the antidepressant drug citalopram down-regulated miR-155 expression and up-regulated SIRT1 expression. These results suggest that miR-155 is an important factor in the pathophysiology of depression. miR-155 is a potential target for the development of new antidepressant treatments.