046 AntiGlucocorticoid Effects of Androstenediol During Cutaneous Wound Healing

Abstract

Wound healing involves many cell types whose functions are dependent upon the coordinated production of multiple cytokines, chemokines, and growth factors. Recent data show that behavioral stress disrupts the cytokine profile and slows wound closure. For example, in mice, restraint stress (RST) suppressed IL-1β, PDGF, and MCP-1 production, and delayed healing of a 3.5 mm circular wound by more than 3 days. The RST-induced delay in healing was due, in part, to elevated glucocorticoids (GC) and could be blocked by administration of the androgen hormone, androstenediol (AED). Therefore, it was hypothesized that AED would antagonize GC-mediated regulation of cytokine gene expression at the transcriptional level, prevent RST-mediated/GC-dependent suppression of cytokine expression at the tissue level, and restore healing to that of controls. Total wound RNA was collected after injury, cDNA was synthesized, and real-time PCR was used to quantify IL-1β RNA as a measure of proinflammatory gene expression and IκBα RNA as a measure of NF-κB transcriptional activation. Compared to controls, RST delayed wound closure (P < 0.001) and decreased IL-1β(P = 0.021) and IκBα expression within 12–24 hours of wounding (P = 0.021). In contrast, treatment of RST animals with AED restored IL-1β gene expression and restored wound closure to that of controls. Additionally, AED enhanced IκBα RNA postinjury (P < 0.001) suggestive of enhanced NF-κB activation. Because of the macrophage’s ability to coordinate inflammatory responses during healing, RAW 264.7 murine macrophages were used to examine modulation of NF-κB activity in AED and GC-treated cells. The data showed that dexamethasone blocked translocation of active p65 which correlated with diminished cytokine gene expression. In contrast, AED restored cytokine gene expression and nuclear p65 levels in GC-treated cultures. In sum, these data suggest that AED antagonized GC-mediated regulation of cytokine gene expression at the transcriptional level and restored cutaneous wound healing to that of unstressed controls. Supported by MH5689, AG16321, DE14304, and DE14320