Big Effects of Small RNAs: A Review of MicroRNAs in Anxiety

Abstract

Epigenetic and regulatory elements provide an additional layer of complexity to the heterogeneity of anxiety disorders. MicroRNAs (miRNAs) are a class of small, noncoding RNAs that have recently drawn interest as epigenetic modulators of gene expression in psychiatric disorders. miRNAs elicit their effects by binding to target messenger RNAs (mRNAs) and hindering translation or accelerating degradation. Considering their role in neuronal differentiation and synaptic plasticity, miRNAs have opened up new investigative avenues in the aetiology and treatment of anxiety disorders. In this review, we provide a thorough analysis of miRNAs, their targets and their functions in the central nervous system (CNS), focusing on their role in anxiety disorders. The involvement of miRNAs in CNS functions (such as neurogenesis, neurite outgrowth, synaptogenesis and synaptic and neural plasticity) and their intricate regulatory role under stressful conditions strongly support their importance in the aetiology of anxiety disorders. Furthermore, miRNAs could provide new avenues for the development of therapeutic targets in anxiety disorders.

miR-494 promotes cell proliferation, migration and invasion, and increased sorafenib resistance in hepatocellular carcinoma by targeting PTEN

“…Each miRNA interacts with numerous mRNA transcripts, a promiscuity that indicates the potential of individual miRNAs to serve as 'master regulators' mediating complex biological processes, such as, embryonic development, cell proliferation, differentiation, migration, apoptosis and signal transduction (7). Evidence indicates that alterations in miRNA expression are associated with numerous disease states, including human cancer (8).…”

Gutsy Moves: The Amygdala as a Critical Node in Microbiota to Brain Signaling

“…[17] Amygdalar expression of microRNAs also appears to be involved in the modulation of anxiety-like behavior. [25] Fear and anxiety are commonly exacerbated by chronic stress. [21] The amygdala appears to have a role in mediating this relationship, and lesions of the central amygdala prevent the manifestation of stress-related anxiety.…”

MicroRNAs in Psychological Stress Reactions and Their Use as Stress-Associated Biomarkers, Especially in Human Saliva

“…Aside from standardized study set-ups investigating changes in miRNA expression responding to psychological stress, such changes can also be observed in several neurological and psychiatric diseases whose genesis and maintenance is at least linked to psychological stress [17,18]. …”

“…All of these studies describe a possible use of miRNAs as biomarker for the respective disease, mainly in peripheral blood. Additionally, an association of miRNAs with several types of anxiety disorders has been reported [18]. Interestingly, a reduced global miRNA expression was found in the prefrontal cortex of depressed suicide completers.…”

“…As stress is an important cofactor in the genesis and maintenance of a variety of acute and chronic diseases such as cardiovascular disease, respiratory infections, and chronic liver disease as well as several types of psychiatric disorders [17,18], stress is of high epidemiological and health-economic relevance [19]. …”