The role of negative pressure wound therapy on TGF-β1, MMP-9, α-SMA, and collagen type III in preventing burn contractures in a porcine model.

INTRODUCTION

Burns are a leading cause of disability and death, requiring prolonged hospitalization and high costs that impair daily activities. Wound healing involves cytokines and growth factors. Despite various treatments, ideal wound dressing remains unidentified. Negative pressure wound therapy (NPWT) has shown potential as an ideal wound healing environment. We compared saline dressings, silver sulfadiazine, intermittent NPWT, and continuous NPWT on wound contraction, re-epithelialization, and biomarkers (MMP-9, TGF-β1, α-SMA, and COL3) in a porcine deep dermal burn model.

METHODS

Six male Yorkshire pigs received 20 burns and were treated with NaCl 0.9% dressings, silver sulfadiazine, intermittent, or continuous NPWT. Wound healing was assessed on days 1, 3, 7, 14, and 21. MMP-9 and TGF-β1 were analyzed using ELISA, α-SMA, and COL3 using immunohistochemistry. Statistical analyses included linear regression, ANOVA, post-hoc tests, and path analyses.

RESULTS

Intermittent NPWT showed the lowest wound contraction on days 14 and 21 (p<0.001) and highest re-epithelialization on day-21 (p=0.0027). MMP-9 and TGF-β1 levels were significantly elevated in both NPWT groups across most time points (days 1, 3, 7, and 14), with TGF-β1 peaking in the NaCl group on day-21. Significant α-SMA histoscores differences appeared on day 3, while COL3 differences were significant on day-14.

CONCLUSIONS

NPWT may reduce wound contraction and accelerates re-epithelialization without impairing wound healing, confirmed by modulation of MMP-9, TGFβ1, α-SMA, and COL3, suggesting the potential to minimize contracture scar formation.