Elucidating the molecular landscape of the stratum corneum

Abstract

Significance Skin is recognized as an intricate assembly of molecular components, which facilitate cell signaling, metabolism, and protein synthesis mechanisms in order to offer protection, regulation, and sensation to the body. Our study takes significant steps to characterize in more detail the complex chemistry of the skin, in particular by generating a better understanding of the uppermost layer, the stratum corneum. Using a state-of-the-art 3D OrbiSIMS technique, we were able to observe the depth distribution, in situ, for a wide range of molecular species. This unprecedented molecular characterization of skin provides information that has the potential to benefit research into fundamental processes, such as those associated with skin aging and disease, and the development and delivery of effective topical formulations.

Design, Synthesis, and Biological Evaluation of Novel Hybrids Containing Dihydrochalcone as Tyrosinase Inhibitors to Treat Skin Hyperpigmentation

“…According to the study of Nichola and co-workers, palmitic acid (C 16 H 31 O 2 – ) can be used to locate the stratum corneum. Cholesterol sulfate (C 27 H 45 SO 4 – ) is then used as an adjunct to locate the uppermost layer of epidermis.…”

“…According to the study of Nichola and co-workers, 57 ) is then used as an adjunct to locate the uppermost layer of epidermis. The white dashed line in Figure 11A indicates the boundary between the stratum corneum and epidermis.…”

The role of excipients in promoting topical and transdermal delivery: Current limitations and future perspectives

“…The SC consists of tightly connected terminally differentiated proteinenriched cells (keratinocytes) embedded in an inter-cellular densely packed lipid lamellae, in a structural arrangement analogous to a 'brick and mortar wall', where the bricks correspond to the corneocytes and the mortar to the lipid matrix (Michaels et al, 1975). The molecular architecture of the SC, including the composition and organization of the lipid domain as well as metabolic responses and cellular signalling underlying barrier repair and homeostasis have been thoroughly discussed in the literature (Proksch et al, 2008;Elias, 2012;Menon et al, 2012;Boncheva, 2014;van Smeden et al, 2014;Neubert, 2018, 2020;Starr et al, 2022). This pattern of SC organization defines the barrier properties and determines the penetration pathways for a molecule to cross the membrane.…”

Untargeted Metabolomic Characterization of Glioblastoma Intra-Tumor Heterogeneity Using OrbiSIMS

“…The technique also employs an argon gas cluster ion beam (GCIB), which is capable of liberating whole molecules from samples due to reduced analyte fragmentation compared with liquid metal ion guns (LMIG) traditionally used in ToF-SIMS, making it particularly applicable to biological materials . OrbiSIMS has been successfully applied in a range of biological samples, such as undigested proteins from human skin, metabolites from single cells, amino acids and lipids from skin, and small molecules on biofilms . A previous study conducted by our group combined OrbiSIMS and liquid extraction surface analysis-tandem MS (LESA-MS/MS) to reveal predictive metabolite signatures of pediatric brain tumor relapse using tumor tissue microarrays, which opened many opportunities to perform in situ metabolomic analysis that may largely improve our understanding of cancer metabolism, an emerging hallmark of cancer .…”