Chen Weiqin, Su Wei, Bi De, Hua Weitian, Zhou Hangyu, Xie Jianing, Chen Sichao, Xu Yongqi, Song Qinghua, Wei Peng
Department of Plastic Surgery, The Affiliated People's Hospital of Ningbo University, Ningbo 315040, China.
Health Science Center, Ningbo University, Ningbo 315211, China.
ACS Biomater Sci Eng. 2025 Jul 14;11(7):4177-4192. doi: 10.1021/acsbiomaterials.4c02259. Epub 2025 Jun 2.
Enhancing flap survival is essential in flap surgery. Cell-free fat extract (Ceffe), a "natural cocktail" of bioactive compounds derived from adipocytes, has demonstrated the potential to improve flap viability. However, direct local injection of Ceffe is limited by its quick leakage and short duration of effectiveness. To address these limitations, this study encapsulated Ceffe in a gelatin methacrylate (GelMA) hydrogel to develop a more stable releasing system. The role of Ceffe in promoting angiogenesis and facilitating flap repair was evaluated by using CCK-8 assays, scratch assays, and tube formation assays. Its antioxidative stress effect was first assessed using flow cytometry and further validated through subsequent experiments employing immunofluorescence and PCR. Scanning electron microscopy (SEM) confirmed that Ceffe@GelMA retained a porous structure, while rheological testing demonstrated its injectability. Drug release assays indicated that GelMA, containing a high concentration of Ceffe, was capable of sustained Ceffe release beneath the flap, thereby promoting flap repair. The biocompatibility of GelMA was assessed using Phalloidin staining, live-dead staining, CCK-8 assays, hemolysis tests, and subcutaneous degradation assay, all of which demonstrated favorable biocompatibility. In a murine random skin flap model, temperature measurements of the flap suggested that Ceffe@GelMA exhibited significant pro-repair activity. Histological analysis through HE and Masson's trichrome staining revealed the presence of abundant neovessels. Immunofluorescence analysis of endothelial marker CD31, vascular endothelial growth factor (VEGF), and smooth muscle actin (α-SMA) further supported that the Ceffe@GelMA treatment group exhibited enhanced pro-angiogenic potential. This study provides substantial evidence supporting Ceffe's therapeutic efficacy in flap necrosis prevention and establishes a Ceffe-incorporated hydrogel system, representing a significant advancement in clinical treatment strategies.
提高皮瓣存活率在皮瓣手术中至关重要。无细胞脂肪提取物（Ceffe）是一种从脂肪细胞中提取的生物活性化合物的“天然混合物”，已显示出改善皮瓣活力的潜力。然而，直接局部注射Ceffe受到其快速渗漏和有效性持续时间短的限制。为了解决这些限制，本研究将Ceffe封装在甲基丙烯酸明胶（GelMA）水凝胶中，以开发一种更稳定的释放系统。通过CCK-8测定、划痕试验和管形成试验评估了Ceffe在促进血管生成和促进皮瓣修复中的作用。首先使用流式细胞术评估其抗氧化应激作用，并通过随后的免疫荧光和PCR实验进一步验证。扫描电子显微镜（SEM）证实Ceffe@GelMA保留了多孔结构，而流变学测试证明了其可注射性。药物释放试验表明，含有高浓度Ceffe的GelMA能够在皮瓣下方持续释放Ceffe，从而促进皮瓣修复。使用鬼笔环肽染色、活死染色、CCK-8测定、溶血试验和皮下降解试验评估了GelMA的生物相容性，所有这些都表明其具有良好的生物相容性。在小鼠随机皮瓣模型中，皮瓣温度测量表明Ceffe@GelMA表现出显著的促修复活性。通过苏木精-伊红（HE）和马松三色染色的组织学分析显示存在丰富的新血管。对内皮标志物CD31、血管内皮生长因子（VEGF）和平滑肌肌动蛋白（α-SMA）的免疫荧光分析进一步支持Ceffe@GelMA治疗组表现出增强了促血管生成潜力。本研究提供了大量证据支持Ceffe在预防皮瓣坏死方面的治疗效果，并建立了一种包含Ceffe的水凝胶系统，代表了临床治疗策略的重大进展。
