A preliminary analysis of association betweenplasma microRNA expression alteration andsymptomatology improvement in Major DepressiveDisorder (MDD) patients before andafter antidepressant treatment

ABSTRACT

Background and Objectives: Currently, there is a serious need to find practical biomarker(s) for Major Depressive Disorder (MDD) therapeutic target(s). This study aimed to investigate the association between microRNA (miRNA, miR) expression level in Peripheral Blood Mononuclear Cells (PBMCs) and symptomatology improvement in MDD patients before and after six-week antidepressant treatment. Methods: By using an Affymetrix array that covers 723 human miRNAs, 26 miRNAs were identified with significantly altered expression in PBMCs in MDD patients, of which10 miRNAs were selected for quantitative real-time Reverse Transcription Polymerase Chain Reaction (RT-PCR) study. Twenty out of all the 81 MDD patients were selected formiRNA expression levels testing and symptomatology assessments before and after sixweektreatment. Results: Compared with the control group, the expression levels of miR-26b, miR-4743, miR-4498, miR-4485 and miR-1972 of the MDD group were significantly higher(P < 0.05); the changes of expression levels of miR-4743, miR-4498, miR-4485 and miR-1972 were positively related to retardation improvement (P < 0.05), and the change of expression level of miR-26b negatively to the improvement of day and night change(P < 0.05); regression analysis result demonstrated that the alteration of miR-4485 expression accounted for 28.8% of retardation improvement (P < 0.05). Conclusions: These five miRNAs (miR-4743, miR-4498, miR-4485, miR-1972 andmiR-26b) may serve as biomarker for MDD diagnosis and therapeutic targets for MDDtreatment (AU)