552 Skin metaproteomics a key functional approach to study skin healthiness and resilience

Abstract

Our skin health and its resilience against assaults (pollution, climatic conditions, pathogens) rests mainly on the epidermis and its microbiome. Indeed, the skin is colonized by commensal beneficial microorganisms called microbiome. This complex ecosystem is a shield for our skin ensuring protective functions while educating our immune system. Unfortunately, when both epidermis and microbiome are fragilized diseases occur. Thus, taking care of its epidermis and microbiome is crucial to preserve skin healthiness. Therefore, studying epidermis and its microbiome with adapted methodologies to clinical sampling might help to gain valuable insight during the development of solutions dedicated to skin health. The option we choose is metaproteomics, which has only been used in gut microbiota field. In contrast to metagenomics, metaproteomics provide valuable descriptive and functional insights simultaneously on these two allies with complex interplay: the epidermis and the microbiome. The aim of this work is to demonstrate in a randomized clinical study, the efficiency of a natural active ingredient (obtained from white biotechnology) to provide skin healthiness using metaproteomics. Skin swabs were sampled from women’s faces before and after the use of a cosmetic formula. The results demonstrate that the active ingredient wasn’t harmful to skin microbiome, keeping its composition stable. We identified 20042 peptides belonging to 4785 proteins. Among them, 343 proteins were significantly modulated (from human, fungi and bacterial origins) impacting positively anti-oxidant, proteostasis, metabolism, anti-inflammation and extra-cellular matrix pathways. Finally, these clinical results highlight that metaproteomics is a powerful technology allowing to demonstrate that modulating proteins expression at keratinocytes and microbiome levels lead clearly to clinical and visible outcomes: improvement of skin wrinkles, mechanical properties and skin barrier function.