Stratum corneum keratin filaments and associated structural proteins

The stratum corneum keratin filaments and associated structural proteins, including filaggrin, loricrin, and involucrin, form the essential physical barrier of the epidermis (StatPearls, 2023). These proteins are organized into a complex network where keratin intermediate filaments (primarily Keratin 1 and Keratin 10) are bundled by filaggrin to provide mechanical strength and structural integrity to corneocytes (PubMed, PMID: 22174400). This protein-lipid matrix prevents excessive transepidermal water loss and protects against environmental insults, such as pathogens and UV radiation (UniProt, P20930). Genetic defects or acquired deficiencies in these proteins, particularly filaggrin, are strongly associated with skin disorders like atopic dermatitis, ichthyosis vulgaris, and psoriasis (PubMed, PMID: 18483305). Pharmacological targeting of this complex involves the use of keratolytics to break down excess keratin in hyperkeratotic conditions and humectants to restore the hydration provided by natural moisturizing factors (PubChem, CID 338). Furthermore, topical retinoids and vitamin D analogs are employed to regulate the differentiation of keratinocytes and the subsequent assembly of these structural proteins (PubMed, PMID: 25545761).

Other names

Cornified envelope proteinsKeratin-filaggrin complexEpidermal structural proteinsStratum corneum barrier proteins

Keratolytic agents like salicylic acid reduce keratinocyte adhesion by solubilizing the intercellular cement and disrupting keratin filament cross-linking, while humectants like urea increase the hydration of the keratin matrix (StatPearls, 2023; PubChem, CID 338). Retinoids modulate the expression of keratin genes and associated proteins to normalize the cornification process (PubMed, PMID: 25545761).