Mutations in 3β‐hydroxysteroid‐δ8, δ7‐isomerase paradoxically benefit epidermal permeability barrier homeostasis in mice

xlomafota13 shared this article with you from Inoreader Mutations in 3β‐hydroxysteroid‐δ8, δ7‐isomerase paradoxically benefit epidermal permeability barrier homeostasis in mice Via Experimental Dermatology Abstract Inherited or acquired blockade of distal steps in the cholesterol synthetic pathway results in ichthyosis, due to reduced cholesterol production and/or the accumulation of toxic metabolic precursors, while inhibition of epidermal cholesterol synthesis compromises epidermal permeability barrier homeostasis. We showed here that 3β‐hydroxysteroid‐δ8, δ7‐isomerase‐deficient mice (TD), an analog for CHILD syndrome in humans, exhibited not only lower basal transepidermal water loss rates, but also accelerated permeability barrier recovery despite the lower expression levels of mRNA for epidermal differentiation marker‐related proteins and lipid synthetic enzymes. Moreover, TD mice displayed low skin surface pH, paralleled by increased expression levels of mRNA for sodium/hydrogen exchanger 1 (NHE1), and increased antimicrobial peptide expression, compared to wild type (WT) mice, which may compensate for the decreased differentiation and lipid synthesis. Additionally, in com parison with WT controls, TD mice showed a significant reduction in ear thickness following challenges with either phorbol ester or oxazolone. However, TD mice exhibited growth retardation. Together, these results demonstrate that 3β‐hydroxysteroid‐δ8, δ7‐isomerase deficiency does not compromise epidermal permeability barrier in mice, suggesting that alterations in epidermal function depend on which step of the cholesterol synthetic pathway is interrupted. But whether these findings in mice could be mirrored in humans remains to be determined. View on the web Inoreader. Take back control of your news feed. Follow us on Twitter and Facebook.