Lipids are highly diverse biomolecules essential for the formation and function of cellular membranes, metabolism, and for cellular signaling. In the mammalian skin, they also help in the formation of the epidermal barrier and as surface lipids, with this combination helping to regulate permeability, physical properties, acidification and antimicrobial defense. 

Recent advances in accuracy and specificity of mass spectrometry have facilitated studying enzymatic and non-enzymatic modifications of lipids—the epilipidome—multiplying the known diversity of molecules in this class. Since the skin is frequently exposed to oxidative-, chemical- and thermal stress, and to injury and inflammation, it can be an ideal organ to study epilipidome dynamics, their causes, and their biological consequences. 

Recent studies explain loss or gain in biological function caused due to either specific modifications or the sum of the modifications of lipids. These studies imply an important role for the epilipidome in stress responses and immune regulation in the skin. 

Source- Gruber F, Marchetti-Deschmann M, Kremslehner C, Schosserer M. The Skin Epilipidome in Stress, Aging, and Inflammation. Front Endocrinol (Lausanne). 2021;11:607076. Published 2021 Jan 21. doi:10.3389/fendo.2020.607076