Sweat lipid mediator profiling: a non-invasive approach for cutaneous research.

Recent advances in analytical and sweat collection techniques provide new opportunities to identify non-invasive biomarkers for the study of skin inflammation and repair. This study aims to characterize the lipid mediator profile including oxygenated lipids, endocannabinoids and ceramides/sphingoid bases in sweat and identify differences in these profiles between sweat collected from non-lesional sites on the unflared volar forearm of subjects with and without atopic dermatitis (AD). Adapting routine procedures developed for plasma analysis, over 100 lipid mediators were profiled using liquid chromatography-tandem mass spectrometry and 58 lipid mediators were detected in sweat. Lipid mediator concentrations were not affected by sampling or storage conditions. Increases in concentrations of C30-C40 [NS] and [NdS] ceramides, and C18:1 sphingosine, were observed in the sweat of study participants with AD despite no differences being observed in transepidermal water loss between study groups, and this effect was strongest in men (p < 0.05, one way ANOVA with Tukey’s post-hoc HSD). No differences in oxylipins and endocannabinoids were observed between study groups. Sweat mediator profiling may therefore provide a non-invasive diagnostic for AD prior to the presentation of clinical signs.

Copyright © 2016, The American Society for Biochemistry and Molecular Biology.