social stress, epigenetic changes and pain

Aims: Bullying is a prevalent issue in society, with adverse effects ranging from psychological symptoms to somatic ailments like chronic pain. The purpose of this study was to generate new knowledge about the underlying... [ view full abstract ]

Aims: Bullying is a prevalent issue in society, with adverse effects ranging from psychological symptoms to somatic ailments like chronic pain. The purpose of this study was to generate new knowledge about the underlying mechanisms behind this association. Using an animal model, we investigated the changes in microRNA expression in plasma, in the pituitary gland and the adrenal gland following social stress.

Methods: A resident-intruder paradigm where male Sprague Dawley rats (intruders) were exposed to male Long Evans rats (resident) one hour daily for a week, was used. Bodyweight was measured and blood samples were collected throughout the experiment. Changes in plasma microRNA expression was determined by qPCR.

Results: Rats exposed to social stress showed reduced weight gain compared to controls. Preliminary results suggested that social stress increased the plasma expression of miR-146a-5p, miR-30c-5p and miR-223-3p.

Conclusions: The data showed that social stress gives reduced weight gain and increase changes in the expression of several circulating microRNAs. How this affects the development of persistent pain remains to be investigated.