Background
Less apoptosis and excessive growth of fibroblasts contribute to the progression of hypertrophic scar formation. Cuprous oxide nanoparticles (CONPs) could have not only inhibited tumor by inducing apoptosis and inhibiting proliferation of tumor cells, but also promoted wound healing. The
Conclusion
CONPs possessed the therapeutic potential in the treatment of hypertrophic scar by inhibiting HSFs proliferation and inducing HSFs apoptosis.
Methods
In vivo, a rabbit ear scar model was established on New Zealand albino rabbits. Six full-thickness and circular wounds (10 mm diameter) were made to each ear. Following complete re-epithelization observed on postoperative day 14, an intralesional injection of CONPs or 5% glucose solution was conducted to the wounds. The photo and ultrasonography of each wound were taken every week and scars were harvested on day 35 for further histomorphometric analysis. In vitro, the role of CONPs in human hypertrophic scar fibroblasts (HSFs) apoptosis and proliferation were evaluated by Tunnel assay, Annexin V/PI staining, cell cycle analysis, and EdU proliferation assay. The endocytosis of CONPs by fibroblasts were detected through transmission electron microscopy (TEM) and the mitochondrial membrane potential and ROS production were also detected.
Results
In vivo, intralesional injections of CONPs could significantly improve the scar appearance and collagen arrangement, and decreased scar elevation index (SEI). In vitro, CONPs could prominently inhibit proliferation and induce apoptosis in HSFs in a concentration-dependent manner. In addition, CONPs could be endocytosed into mitochondria，damage the mitochondrial membrane potential and increase ROS production.