The factors involved in maintaining a localized inflammatory state in psoriatic skin remain poorly understood. Here, we demonstrate through metabolomic and transcriptomic profiling marked suppression of glucocorticoid biosynthesis in the epidermis of psoriatic skin leading to localized deficiency of cortisol. Utilizing a 3D human epidermis model, we demonstrate that glucocorticoid biosynthesis is suppressed by pro-inflammatory cytokines and that glucocorticoid deficiency promotes inflammatory responses in keratinocytes. Finally, we show in vitro and in vivo that treatment with topical glucocorticoids leads to rapid restoration of glucocorticoid biosynthesis gene expression coincident with normalization of epidermal differentiation and suppression of inflammatory responses. Taken together, our data suggest that localized glucocorticoid deficiency in psoriatic skin interferes with epidermal differentiation and promotes a sustained and localized inflammatory response. This may shed new light on the mechanism of action of topical steroids, and demonstrates the critical role of endogenous steroid in maintaining both inflammatory and differentiation homeostasis in the epidermis.

Background-Choosing the appropriate treatment for grade IIIB and IIIC open tibial fractures is a difficult decision for both the patient and the physician. Current research shows that the functional outcomes for reconstruction are similar to those for below-knee amputation, but little investigation of the qualitative outcomes of either treatment option has been done from the patient perspective. This study was designed to perform a qualitative analysis of patient preferences for amputation or reconstruction.