Characterization of Xenobiotic Metabolizing Enzymes of a Reconstructed Human Epidermal Model from Adult Hair Follicles
September 2017
in “
The journal of investigative dermatology/Journal of investigative dermatology
”
reconstructed human epidermal model outer root sheath hair follicles xenobiotic metabolizing enzymes cytochromes P450 CYPs alcohol dehydrogenases aldehyde dehydrogenases carboxyl esterases Phase I XME genes Phase II XMEs GSTs transferases CYP inducers 3-methylcholanthrene beta-naphthoflavone UGTs SULTs 7-ethoxycoumarin testosterone benzo(a)pyrene AhR ligands reconstructed skin model ORS-RHE hair follicle model xenobiotic enzymes CYP enzymes alcohol enzymes aldehyde enzymes esterases Phase I enzymes Phase II enzymes glutathione S-transferases 3-MC BNF UGT enzymes SULT enzymes
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TLDR The reconstructed skin model from hair follicles functions like human skin in processing chemicals and can be used to test ingredient safety.
The document presents a study on a reconstructed skin epidermal model derived from the outer root sheath of hair follicles (ORS-RHE), which was used to characterize xenobiotic metabolizing enzymes (XMEs). The gene expression profile of XMEs in the ORS-RHE model was consistent with that of native human skin, including the presence of cytochromes P450 (CYPs). The model showed high expression levels of Phase I XME genes, particularly alcohol/aldehyde dehydrogenases and (carboxyl) esterases, and even higher levels of Phase II XMEs, with GSTs and transferases being the most prominent. The model responded to CYP inducers, such as 3-methylcholanthrene (3-MC) and beta-naphthoflavone (BNF), both topically and systemically, with increased gene expression and enzyme activity. Functional activities of CYPs, UGTs, and SULTs were confirmed by the rapid metabolism of substances like 7-ethoxycoumarin, testosterone, benzo(a)pyrene, and 3-MC within 24 hours of topical application. The extent of metabolism was influenced by the enzymes' saturation and the residence time within the model. The study concluded that the ORS-RHE model expresses functional Phase I and II XMEs, some of which can be induced by AhR ligands, making it a valuable tool for evaluating the metabolism and potential toxicity of dermo-cosmetic ingredients.