The effects of decellularized amniotic membrane and Wharton’s jelly on the healing of experimental skin wounds in rats

Several studies have focused on novel therapeutic strategies for extensive skin lesions aiming to improve healing quality and reduce treatment duration. In this context, the use of amniotic membrane (AM) and Wharton's jelly (WJ) emerges as promising alternatives. Full-thickness dorsal skin wounds were created in 21 Wistar rats, randomly divided into three groups: control (C), AM - covered by AM and WJ - covered by WJ. Wound contraction rate was measured weekly. On day 28, histochemical (Picrosirius red) and immunohistochemical analyses matrix metalloproteinase-9 (MMP-9), transforming growth factor beta (TGF-β), and alpha-smooth muscle actin (α-SMA) were performed. On day seven, wound contraction rate was higher in the AM group (38.8%), followed by the WJ (27.4%) and control (26.5%) with statistically significance. During the first 14 days, the AM group maintained the highest contraction rate, followed by the control and WJ groups. However, by day 21, wound contraction rates increased in the order of WJ to AM to control groups (85.6%, 87.0%, and 91.1%) with statistically significance. Type I collagen predominated across all groups, without statistically significant differences among them. TGF-β expression significantly increased from WJ to AM to control groups (19.75%, 26.00%, and 36.56%) with statistically significance. MMP-9 and α-SMA expressions decreased from control to WJ to AM groups, but no significant differences were observed. Both AM and WJ enhanced early wound contraction and may support skin repair by attenuating fibrotic signaling. These findings highlight the potential of AM and WJ as biomaterials for promoting tissue regeneration at epithelial barriers.