# Dual‐Targeting Oligopeptide‐215 Regulates Skin Barrier Homeostasis Through Concurrent Modulation of JAK–STAT and NF‐κB Signaling

## TL;DR

Oligopeptide-215 helps repair skin by boosting barrier proteins and reducing inflammation through two key signaling pathways.

## Contribution

Oligopeptide-215 is a novel biomimetic peptide that concurrently modulates JAK–STAT and NF-κB pathways to restore skin barrier function.

## Key findings

- Oligopeptide-215 restores FLG and LOR expression by antagonizing IL-13/IL-4-mediated JAK–STAT6/STAT3 signaling.
- It suppresses inflammation by inhibiting NF-κB-dependent cytokine production in macrophages.
- In UVB-damaged keratinocytes, it promotes repair through enhanced cell proliferation, adhesion, and migration.

## Abstract

To evaluate Oligopeptide‐215, a biomimetic peptide engineered from amphibian skin secretions, for its dual capacity to restore skin barrier homeostasis by concurrently targeting physical barrier proteins and inflammatory pathways via JAK–STAT and NF‐κB modulation.

In vitro models used UVB‐damaged HaCaT keratinocytes, LPS‐stimulated RAW264.7 macrophages, and IL‐4/IL‐13‐stimulated HaCaT cells. Assays included cell viability (MTT), migration (scratch), adhesion, barrier proteins (FLG/LOR; ELISA/IF), signaling phosphoproteins (pJAK1/pTYK2/pSTAT3/pSTAT6/pNF‐κB; IF), and inflammatory mediators (NO/PGE₂/TNF‐α/IL‐6/IL‐1β; ELISA).

Oligopeptide‐215 antagonizes IL‐13/IL‐4‐mediated JAK–STAT6/STAT3 signaling, thereby restoring expression of critical barrier proteins FLG and LOR. Additionally, it suppresses inflammatory responses by inhibiting NF‐κB‐dependent cytokine production. In UVB‐damaged keratinocytes, Oligopeptide‐215 promotes cellular repair through enhanced proliferation, adhesion, and migration.

These findings revealed an innovative repairing mechanism combining physical barrier with immunologic barrier, and established Oligopeptide‐215 as a potential skincare ingredient for skin barrier dysfunction.