Abstract

Increased Levels of miR-30e, miR-132, miR-185, and miR- 212 at Baseline and Increased Brain-derived Neurotrophic Factor Protein and mRNA Levels after Treatment in Patients with Major Depressive Disorder

Author(s): Chin-Chuen Lin, Chien-Te Lee, Ming-Hsiang Sun, Tiao-Lai Huang

Abstract

Background: Brain-derived neurotrophic factor (BDNF) is involved in the pathophysiology of major depressive disorder (MDD). In recent years, epigenetic modifications of BDNF in patients of MDD had been investigated, and the role of microRNAs (miRNAs) had not been widely addressed.

Methods:From December 2015 to November 2016, patients with MDD and healthy controls were recruited from a medical center in Taiwan. Their serum BDNF protein, BDNF mRNA, and ten miRNAs related to BDNF (miR-16, miR-30e, miR-34c-5p, miR-128, miR-132, miR-134, miR-182, miR-183, miR-185,
miR-212) levels were measured and analysed. Some patients required hospitalization, and those markers were measured again after four-week antidepressant treatment.

Results: Seventy-four subjects were recruited, including thirty-four patients with MDD and forty healthy controls. Using t-test, patients with MDD had higher levels of miR-30e, miR-132, miR-185, and miR-212 than healthy controls (p = 0.006, 0.000, 0.024, and 0.008, respectively). Using ANCOVA adjusted for sex and age, no statistical significance was found, however. Nineteen patients received one-month antidepressant treatments. Using Wilcoxon signed rank test, BDNF protein and mRNA levels increased significantly after treatment (p = 0.016 and 0.033, respectively). Their miRNA levels showed no significant change after the treatment.

Conclusion: Serum miR-30e, miR-132, miR-185, and miR-212 levels were significantly increased in patients with MDD at baseline compared to healthy controls, suggesting miRNAs could be used as potential diagnostic biomarkers. BDNF protein and mRNA levels increased significantly after antidepressant treatment. Antidepressant treatment did not change miRNA levels significantly in our study, probably due to shorter treatment period or small sample size.