Changes in miRNA-132 and miR-124 levels in non-treated and citalopram-treated patients with depression.

BACKGROUND: Neurotrophins including brain-derived neurotropic factor (BDNF) are implicated in the pathogenesis of major depressive disorder (MDD). Yet, the roles of brain-specific BDNF-related miRNAs miR-132 and miR-124 are unclear.

METHODS: We enrolled 45 treatment-free patients with MDD, 32 citalopram-treated patients with MDD, and 32 healthy control subjects. Participants were assessed with the Hamilton Depression Scale (HAMD) and Hamilton Anxiety Scale (HAMA). In a case-control sub-study, we followed 14 treatment-free patients who were subsequently treated with citalopram for 2 months. Enzyme-linked immunosorbent assay was used to detect plasma BDNF, and real-time polymerase chain reaction was used to quantify relative plasma miR-132 and miR-124 expression.

RESULTS: Patients with MDD had significantly higher HAMA and HAMD scores than the control group, with the highest scores in the treatment-free MDD group. Plasma miR-132 in the treatment-free MDD group was 2.4-fold that in the control group and significantly higher than that in the citalopram-treated MDD group. Plasma miR-124 in the treatment-free MDD and citalopram-treated MDD groups was 1.8-fold and 4-fold that in the control group, respectively. Compared to the control group, plasma BDNF levels were increased in both MDD groups, but not significantly different between them. There was a positive correlation between miR-132 and HAMD and HAMA scores, whereas no significant correlations were identified for plasma miR-124 or BDNF.

LIMITATIONS: The range of neurotrophin-related MiRNAs and the number of follow-up cases were limited.

CONCLUSIONS: BDNF and miR-124 in plasma increase with depression and antidepressants. Plasma MiR-132 might be an indication for depression status.