Chronic Academic Stress Increases a Group of microRNAs in Peripheral Blood

Abstract

MicroRNAs (miRNAs) play key roles in regulation of cellular processes in response to changes in environment. In this study, we examined alterations in miRNA profiles in peripheral blood from 25 male medical students two months and two days before the National Examination for Medical Practitioners. Blood obtained one month after the examination were used as baseline controls. Levels of seven miRNAs (miR-16, -20b, -26b, -29a, -126, -144 and -144*) were significantly elevated during the pre-examination period in association with significant down-regulation of their target mRNAs (WNT4, CCM2, MAK, and FGFR1 mRNAs) two days before the examination. State anxiety assessed two months before the examination was positively and negatively correlated with miR-16 and its target WNT4 mRNA levels, respectively. Fold changes in miR-16 levels from two days before to one month after the examination were inversely correlated with those in WNT4 mRNA levels over the same time points. We also confirmed the interaction between miR-16 and WNT4 3′UTR in HEK293T cells overexpressing FLAG-tagged WNT4 3′UTR and miR-16. Thus, a distinct group of miRNAs in periheral blood may participate in the integrated response to chronic academic stress in healthy young men.

Circulating microRNA-144-5p is associated with depressive disorders

“…It is highly conserved and has multiple predicted targets in both humans and rats [44]. Many studies have demonstrated that miR-144 is involved in the response to mood stabilizer treatment [45], stress responses [46,47], and aging diseases [48]. Long-term treatment with the mood stabilizers lithium and valproate significantly up-regulates miR-144 expression in the rat hippocampus, which is one of the brain regions involved in mood regulation.…”

Intergenerational Transmission of Stress in Humans

“…Furthermore, cortisol, as a part of the glucocorticoid receptor (GR) complex, affects gene transcription and could, ultimately, permanently alter the offspring epigenome (Stahn et al, 2007). Intriguingly, recent evidence also suggests that microRNA, which could itself be regulated by cortisol and has been shown to be regulated by stress, may have a role in intergenerational inheritance (Cortez et al, 2011;Daxinger and Whitelaw, 2012;Honda et al, 2013;Issler and Chen, 2015).…”

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

“…Three of these studies used stressors of everyday life, such as academic exams or tests as events to be expected and therefore functioning as chronic psychological stressors [13,23,24]. …”

“…In 2012 [13] and 2013 [23], a group of scientists from the Department of Stress Science at the University of Tokushima, Japan, investigated alterations in miRNAs in the whole blood in conditions of chronic psychological stress. Katsuura et al [13] examined healthy fourth-grade medical students, taking a nationally administered examination for academic promotion.…”