Serum levels of the steroid hormone dehydroepiandrosterone (DHEA) are associated with psychological trauma and lymphocyte telomere integrity in women suffering from depression.

INTRODUCTION Emerging studies highlight the telomere system as an aging mechanism underlying the association between exposure to psychological trauma and the development of a wide range of physical and mental disorders, including major depressive disorder (MDD). Here, we investigated associations of circulating levels of the steroid hormone dehydroepiandrosterone (DHEA) with immune cell telomere length (TL) in the context of lifetime trauma exposure and MDD. METHODS Lifetime traumatic events (trauma load) were assessed using the Essener Trauma Inventory (ETI) in n=22 postmenopausal female inpatients with MDD and n=22 non-depressed controls. All women completed the Beck's Depression Inventory-II to assess the severity of current depressive symptoms. DHEA concentration in serum was measured by immunoassay and TL was quantified in kilobase units using quantitative fluorescent in situ hybridization (qFISH) in total peripheral blood mononuclear cells (PBMC) and in selected T cell subpopulations isolated by FACS separation. RESULTS Higher trauma load was significantly associated with lower DHEA concentration, which in turn was linked to more depression-related fatigue. Furthermore, DHEA concentration was positively and significantly associated with TL in memory CD4+ T cells as well as in naïve and memory CD8+ T cells, but not in naïve CD4+ T cells and total PBMC. Mediational analysis suggested that DHEA concentration is a mediator in the relationship between trauma load and memory CD8+ T cell TL. CONCLUSION The current findings suggest a potential role of DHEA as a biological resilience factor that may exert beneficial effects on telomere integrity, especially in conditions related to distress.