Inflammatory mediators and skin barrier pathways

Inflammatory mediators and skin barrier pathways refers to the complex interplay between immune signaling molecules and the structural integrity of the epidermis. Pro-inflammatory cytokines, particularly Interleukin-4 (IL-4) and Interleukin-13 (IL-13), are known to downregulate the expression of key barrier proteins such as Filaggrin (FLG), Loricrin, and Involucrin, thereby compromising the skin's protective function (Guttman-Yassky et al., 2019, J Allergy Clin Immunol). This barrier defect facilitates the entry of allergens and pathogens, which further exacerbates the inflammatory response in a "vicious cycle" characteristic of atopic dermatitis and other eczematous conditions (Brown and McLean, 2012, J Invest Dermatol). Signaling through the Janus kinase (JAK) pathway is a critical downstream component of these inflammatory mediators, influencing both cytokine production and the synthesis of barrier-forming lipids like ceramides (Bissonnette et al., 2019, BMC Dermatol). Modern therapeutic approaches target this axis by inhibiting specific cytokines (e.g., with Dupilumab or Tralokinumab) or blocking intracellular signaling (e.g., with JAK inhibitors) to reduce inflammation and allow for barrier repair. Consequently, this term describes a broad pathophysiological mechanism rather than a single, discrete therapeutic target.

Other names

Skin barrier dysfunctionEpidermal barrier signalingTh2-mediated skin inflammationCutaneous inflammatory axis

Inhibition of pro-inflammatory cytokines (e.g., IL-4, IL-13) and downstream signaling (e.g., JAK/STAT) to restore the expression of epidermal structural proteins and lipid synthesis.