Atopic dermatitis (AD) is a chronic, relapsing inflammatory skin condition affecting around 20% of children and up to 10% of adults in high-income countries. The pathogenesis of AD is diverse and complex, involving genetic susceptibility, impaired skin barrier function, dysfunctional cell-mediated immunity, changes in skin microflora, and environmental and lifestyle factors. Therefore, investigation of metabolic changes related to AD is necessary to better understand the pathogenesis and develop potential treatments.

In this study, a non-targeted metabolomics approach was introduced to determine key metabolite factors related to AD in tape-stripped stratum corneum (SC) samples. The polar extracts from normal and AD patients’ SC samples were analyzed using a high-resolution Q-TOF mass spectrometer equipped with a UHPLC system. Based on molecular features extracted from UHPLC/Q-TOF MS datasets, principal component analysis (PCA) and partial least squares-discriminant analysis (PLS-DA) were performed. The PLS-DA plot showed distinct separations among normal and AD patients’ samples, and we found 70 key metabolites contributing to the discrimination of normal and AD patients’ lesional skin. These findings would enable us to better understand the pathogenesis of AD and to provide more information on target molecules to develop new treatments for AD.