METHODS: Rat aortic endothelial cells and fibroblasts were cultured with ADSC-CM collected under 0%, 10%, 12%, and 15% stretching force. Ten-milliliter cylindrical soft tissue expanders were subcutaneously implanted into the backs of 36 Sprague-Dawley rats. The 0% and 10% stretch groups were injected with ADSC-CM collected under 0% and 10% stretching force, respectively, while the control group was not injected. After 3, 7, 14, and 30 days of expansion, expanded skin tissue was harvested for staining and qPCR analyses.
RESULTS: Endothelial cells had the best lumen formation and highest migration rate, and fibroblasts secreted the most collagen upon culture with ADSC-CM collected under 10% stretching force. The skin expansion rate was significantly increased in the 10% stretch group. After 7 days of expansion, the number of blood vessels in the expanded area, expression of the angiogenesis-associated proteins vascular endothelial growth factor, basic fibroblast growth factor, and hepatocyte growth factor, and collagen deposition were significantly increased in the 10% stretch group.
CONCLUSIONS: The optimal mechanical force upregulates specific paracrine proteins in ADSCs to increase angiogenesis and collagen secretion, and thereby promote skin regeneration and expansion. This study provides a new auxiliary method to expand large skin flaps.
方法:用ADSC-CM培养大鼠主动脉内皮细胞和成纤维细胞,10%,12%,和15%的拉伸力。将10毫升圆柱形软组织扩张器皮下植入36只Sprague-Dawley大鼠的背部。0%和10%拉伸组注射在0%和10%拉伸力下收集的ADSC-CM,分别,对照组不注射。经过3、7、14和30天的扩张,收获扩增的皮肤组织用于染色和qPCR分析。
结果:内皮细胞的管腔形成最好,迁移率最高,在10%拉伸力下收集的ADSC-CM培养后,成纤维细胞分泌的胶原蛋白最多。10%牵张组皮肤扩张率显著增长。经过7天的扩张,扩张区域的血管数量,血管生成相关蛋白血管内皮生长因子的表达,碱性成纤维细胞生长因子,和肝细胞生长因子,10%拉伸组胶原沉积明显增加。
结论:最佳机械力上调ADSCs中的特定旁分泌蛋白,以增加血管生成和胶原分泌,从而促进皮肤再生和扩张。本研究为扩张大型皮瓣提供了一种新的辅助方法。