Keratinized skin structures

Keratinized skin structures, primarily the stratum corneum, hair, and nails, represent the terminal product of keratinocyte differentiation and serve as the body's essential physical barrier (StatPearls, 2023). These structures are composed of dead, flattened cells called corneocytes that are packed with keratin intermediate filaments and surrounded by a lipid-rich extracellular matrix, which provides mechanical strength and prevents excessive transepidermal water loss (NIH, 2022). In various dermatological conditions such as psoriasis, ichthyosis, and hyperkeratosis, the process of keratinization becomes dysregulated, leading to the accumulation of thickened, scaling, and often dysfunctional tissue (PubMed, PMC7230126). Pharmacological intervention typically targets these structures using keratolytic agents like salicylic acid or urea, which soften the skin by breaking down the protein matrix and promoting the shedding of the cornified layer (PubChem, CID 338). Additionally, because these structures are rich in keratin, they serve as the primary site for dermatophytic fungal infections, requiring antifungal drugs that can effectively penetrate and accumulate within these dense proteinaceous environments (Journal of Fungi, 2021).

Other names

Stratum corneumCornified layerKeratinized tissueHorny layerCornified envelope

Keratolysis through the dissolution of the intercellular cement (desmosomes) and reduction of corneocyte adhesion, alongside the modulation of keratinocyte differentiation and proliferation (StatPearls, 2023; PubChem, CID 338).