microRNA 320a is a potential mediator of chronic widespread hyperalgesia development after stress exposure (2016)

Undergraduate: Kyle Riker

Faculty Advisor: Sarah Linnstaedt
Department: Chemistry

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Widespread hyperalgesia (WH) induced by unpredictable sound stress (USS) has been shown to be mediated by increased glucocorticoid and catecholamine levels acting at the level of the peripheral nerve. Recent studies have found that circulating levels of miRNA 320a are associated with fibromyalgia, and suggest that miR-320a targets multiple transcripts associated with glucocorticoid synthesis/regulation. Based on these data, we evaluated whether circulating miR-320a levels predict chronic widespread pain (CWP) and fibromyalgia development after motor vehicle collision (MVC) stress exposure in humans, miR-320a is expressed in tissues relevant to identified mechanisms mediating WH induced by induced by USS, and if miR-320a regulates glucocorticoid system-related transcripts in cell culture consistent with previous in silico analyses. We found that among African Americans presenting to the ED after MVC, reduced circulating miRNA-320a isoform levels in the ED predict both CWP and fibromyalgia at six months. In animals miR-320a is expressed in tissues relevant to identified mechanisms mediating WH induced by USS, and in neuroblastoma cell lines, miR-320a expression affects glucocorticoid system-related regulatory transcript levels. These data suggest that miR-320a may help mediate the changes in pain sensitivity which occur in some individuals after stress exposure. If confirmed, these data could lead to new treatment interventions for high risk individuals that target miRNA-320a.