Therapeutic Closure: Electro-mechanically Synergistic Sutures for Scarless Repair of High-Tension Wounds

Abstract

High mechanical tension during wound closure typically triggers a pathological scarring cascade. Conventional surgical sutures act merely as passive tissue approximators, lacking the capacity to actively modulate this detrimental microenvironment. Herein, we establish a “closure as treatment” paradigm through the development of an electromechanically synergistic smart suture (S@VP@PPy) designed for scarless repair of high-tension wounds. The system features a hierarchical bilayer architecture comprising a verteporfin (VP)-loaded chitosan/gelatin drug reservoir and a conductive polypyrrole (PPy) outer coating. Transcriptomic and spatiotemporal protein analyses reveal a molecular division of labor. VP pharmacologically intercepts the transduction of mechanical stress into profibrotic cascades via YAP inhibition, concurrently resolving hyperinflammation and softening the extracellular matrix (ECM) by redirecting fibroblast fate. Within this softened permissive niche, PPy-mediated bioelectric stimulation accelerates re-epithelialization and activates the Wnt/β-catenin pathway to drive hair placode invagination. In a rat dorsal high-tension model, this spatiotemporal cooperation successfully intercepts the “tension-inflammation-fibrosis” cascade, culminating in scarless healing with de novo appendage regeneration.

Keywords

Multifunctional surgical sutures / Electroactive / High-tension wound / Scarless healing / Hair follicle regeneration

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Funding

the National Natural Science Foundation of China(82272266)

the Natural Science Foundation of Shanghai(25ZR1401231)

the Fundamental Research Funds for the Central Universities(YG2025QNB18)

the Shanghai Leading Talent Program

Shanghai Municipal Project for the Development of Innovative Biomedical Products(25S11906600)

Rights & permissions

Donghua University, Shanghai, China