The following is a summary of “Oxytocin prevents dysregulation of the acute stress response and glucocorticoid-induced oxidative stress in chronically isolated prairie voles,” published in the July 2023 issue of Psychoneuroendocrinology by Stevenson et al.

Chronic social isolation may result in the dysregulation of various physiological and psychological processes, which can impact the individual’s capacity to respond effectively to acute stressors. Prior research conducted in researcher’s laboratory has documented that six weeks of social isolation in prairie voles (Microtus ochrogaster) resulted in elevated levels of glucocorticoids, oxidative damage, degradation of telomeres, and anhedonia. Furthermore, it was observed that oxytocin administration effectively mitigated all of these alterations mentioned above. Based on these findings,  they conducted a study to examine the impact of prolonged social isolation, with and without oxytocin intervention, on the glucocorticoid (CORT) and oxidative stress responses during an acute stressor.

The stressor was a 5-minute resident-intruder (R-I) test conducted after the social isolation phase. To examine the impact of a short-term acute stressor on cortisol (CORT) levels and oxidative stress, initial blood samples were obtained after six weeks of social isolation, 24 hours before the Restraint-Immobilization (R-I) test. Two additional blood samples were obtained 15 minutes following the conclusion of the R-I test and once more 25 minutes after that to assess peak and recovery responses, respectively. Animals subjected to isolation exhibited elevated levels of CORT (corticosterone) and reactive oxygen metabolites (ROMs), indicative of increased oxidative stress in baseline, peak, recovery, and integrated measurements compared to non-isolated animals. 

Significantly, administration of oxytocin therapy during isolation effectively mitigated increased cortisol (CORT) levels and reactive oxygen metabolites (ROMs). No notable alterations were observed in the total antioxidant capacity (TAC). The cortisol (CORT) groups and range of motion (ROMs) exhibited a positive correlation at peak and recovery times. These findings indicate that acute stress in prairie voles that are chronically isolated is linked to heightened glucocorticoid-induced oxidative stress (GiOS). Additionally, it is observed that oxytocin helps alleviate the dysregulation of glucocorticoid and oxidative stress acute stress responses caused by isolation.

Source: sciencedirect.com/science/article/abs/pii/S0306453023000999