Alpha terpineol preconditioning enhances regenerative potential of mesenchymal stem cells in full thickness acid burn wounds

Abstract

Regeneration of full thickness burn wounds is a significant clinical challenge. Direct stem cell transplantation at the wound site has a promising effect on wound regeneration. However, stem cell survival within the harsh wound environment is critically compromised. In this regard, preconditioning of stem cells with cytoprotective compounds can improve the efficiency of transplanted cells. This study evaluated the possible effect of alpha terpineol (αT) preconditioned mesenchymal stem cells (αT-MSCs) in full thickness acid burn wound. An optimized concentration of 10 μM αT was used for MSC preconditioning, followed by scratch assay analysis. A novel rat model of full thickness acid burn wound was developed and characterized via macroscopic and histological examinations. Treatment (normal and αT-MSCs) was given after 48 h of burn wound induction, and the healing pattern was examined till day 40. Skin tissues were harvested at the early (day 10) and late (day 40) wound healing phases and examined by histological grading, neovascularization, and gene expression profiling of healing mediators. In scratch assay, αT-MSCs exhibited enhanced cell migration and wound closure (scratch gap) compared to normal MSCs. In vivo findings revealed enhanced regeneration in the wound treated with αT-MSCs compared to normal MSCs and untreated control. Histology revealed enhanced collagen deposition with regenerated skin layers in normal MSC- and αT-MSC treated groups compared to the untreated control. These findings were correlated with enhanced expression of α-SMA as shown by immunohistochemistry. Additionally, αT-MSC group showed reduced inflammation and oxidative stress, and enhanced regeneration, as witnessed by a decrease in IL-1β, IL-6, TNF-α, and Bax and an increase in BCL-2, PRDX-4, GPX-7, SOD-1, VEGF, EGF, FGF, MMP-9, PDGF, and TGF-β gene expression levels at early and late phases, respectively. Overall findings demonstrated that αT exerts its therapeutic effect by mitigating excessive inflammation and oxidative stress while concurrently enhancing neovascularization. Thus, this study offers new perspectives on managing full thickness acid burn wounds in future clinical settings.