A natural deep eutectic system modulates the inflammatory microenvironment and restores pro-regenerative cell...

Chronic wounds are characterized by persistent inflammatory microenvironments that impair angiogenesis, fibroblast migration, and keratinocyte re-epithelialization. Sustained inflammation disrupts regenerative signalling, thereby limiting effective tissue repair. Therapeutic strategies should therefore actively modulate inflammatory pathways. Natural deep eutectic systems (NaDES) have emerged as supramolecular systems capable of dynamic biological interaction. We investigated whether a betaine-urea eutectic system (BU) can function as a bioactive platform capable of restoring regenerative cellular processes under inflammatory stress.

Inflammatory activity was evaluated in M1-polarized macrophages by RT-qPCR analysis of IL6, IL8, TNFα, and IL1β. Modulation NF-κB activation was assessed in THP-1 Dual reporter cells via measuring SEAP activity. Inflammatory conditions were induced using TNF-α and LPS. Endothelial morphogenesis (EA. hy926) was assessed using capillary-like network formation assays. Skin fibroblast (HDFn) and keratinocyte (HaCaT) migration were evaluated using transwell assays, and extracellular matrix remodelling was analysed using invasion models. The antioxidant effect was also evaluated using the cell-permeable fluorescent probe 2',7'-dichlorodihydrofluorescein diacetate in the same cell types.

BU significantly reduced LPS-induced pro-inflammatory cytokine expression and attenuated NF-κB activation in THP-1 derived macrophages. Under inflammatory stimulation, BU restored endothelial network formation compared with inflammatory controls. These effects were not reproduced by betaine or urea alone. BU also enhanced extracellular matrix permissiveness and restored fibroblast and keratinocyte migratory capacity. The antioxidant effect of BU was observed only for M1 macrophages, suggesting cellular-type selective mechanisms.

BU acts as a supramolecular liquid system that modulates NF-κB-mediated inflammation and restores endothelial network formation and cellular migration. Beyond its previously demonstrated debridement and anti-biofilm activities, BU represents a promising nanostructured bioactive platform for inflammatory wound modulation.