Synaptic plasticity and depression: the role of miRNAs dysregulation

Background: MicroRNAs (miRNAs) have been recently shown to exert several functional roles in the development and function of neurons. Moreover, numerous miRNAs are present in high abundance in presynaptic and postsynaptic sites regulating synaptic plasticity and activity through different mechanisms. Methods: We searched PubMed and Google Scholar databases with key words “Synaptic plasticity”, “miRNA” and “major depressive disorder. Results: Synaptic plasticity has an essential role in the ability of the brain to integrate transitory experiences into constant memory traces. Thus, it participates in the development of neuropsychiatric diseases such as major depressive disorder (MDD). Most notably, MDD-related alterations in synaptic function have been found to be closely related with abnormal expression of miRNAs. Conclusions: Several miRNAs such as miR-9-5p, miR-204-5p, miR-128-3, miR-26a-3p, miR-218, miR‐22‐3p, miR‐124‐3p, miR‐136‐3p, miR‐154‐5p, miR‐323a‐3p, miR-425-5p, miR-34a, miR-137, miR-204-5p, miR-99a, miR-134, miR-124-3p and miR-3130-5p have been shown to be involved in the regulation of synaptic plasticity in the context of MDD. In the current review, we elaborate the role of miRNAs in regulation of this important neuronal feature in MDD.