Scoping review on the relationship between microRNAs (miRNAs) and short sleep disorder or insomnia with short sleep duration.

Background: MicroRNA (miRNA) stands for a class of small, non-coding RNA molecules, typically forming 20 to 25 nucleotides in length, which play a pivotal role in the regulation of gene expression in eukaryotic cells. These molecules are integral to the post-transcriptional regulation of target messenger RNA (mRNA), which they achieve primarily through binding to complementary sequences within the 3' untranslated region (UTR) of the mRNA. miRNAs exert their regulatory effects by binding to their target mRNA, leading to two primary outcomes: mRNA degradation or inhibition of translation. This functionality positions miRNAs as crucial modulators of a variety of biological processes, including cell growth, differentiation, apoptosis, and responses to environmental stress. Furthermore, dysregulation of miRNA expression is associated with pathological conditions, including cancer, cardiovascular disease, and neurological disorders. They are associated with sleep regulation and are helpful in diagnosing diseases, including sleep disturbances. This scoping review aims to summarize existing literature in patients aged 18 to 65 with a main diagnosis of Short Sleep Disorder (SSD), and Insomnia with Short Sleep Duration (ISOSS) and its relationship with miRNAs. The objective of this study is to search for existing evidence on the composition (presence, diversity, and relative abundance) of miRNAs in individuals with and without sleep disturbances, and to know whether the cardiometabolic comorbidities associated with these pathologies imply miRNA alterations. Methods: This scoping review was performed according to the PRISMA-ScR checklist and the systematic literature search was conducted using Medline, Web of Science, and CINAHL, until June 2025. Results: Seven cross-sectional studies form the basis of this ScR. The miRNAs of particular interest include miR-182-5p, miR-4433b-3p, which are implicated in inflammatory pathways, and appear to be downregulated in conditions associated with sleep deprivation, thereby contributing to an exacerbation of pro-inflammatory responses that can lead to cardiovascular dysfunction. Also, miR-619-5p, linked to stress responses and cognitive and emotional health, miR-33a, miR-181d, implicated in lipid metabolism and neuroinflammation, miR-132-3p linked to increased risk of depression and cognitive decline and miR-125a, miR-126, and miR-146a, critical regulators of diverse biological processes, particularly in the context of inflammation and cardiovascular health. Conclusions: The existing literature sets up a foundational understanding of the relationship between miRNAs, insomnia (IS), SSD and ISOSS. Although the current evidence base is limited, dysregulation of specific miRNAs may play a role in the pathophysiology of IS, SSD and ISOSS; however, larger and methodologically standardized studies are required.