脂肪干细胞胶条件培养基快速诱导脂肪再生促进糖尿病创面愈合的机制研究

Chronic wound is a major livelihood issue that urgently needed to be solved. SVF/ASCs cell therapy is considered one of the most promising treatments for chronic wounds. Previous study found that neo-adipogenesis under the wound played an important role in the wound healing process, and the mechanism was that neo-adipogenesis was accompanied by M2 macrophage infiltration. Further studies showed that SVF-gel, enriched in adipose-derived SVF cells and extracellular matrix, accelerated wound healing in diabetic rat by inducing quick neo-adipogenesis and infiltration of M2 macrophages. However, SVF-gel has the disadvantage of being unable to be cultured in laboratory and difficult to preserve in the long-term. Accordingly, we extracted a conditioned medium rich in SVF-gel-related cytokines (Gel-CM). Results show that Gel-CM not only possesses the similar ability on promoting neo-adipogenesis and promoting wound healing, but has the merits of convenient storage and mass production. The following research will focus on the mechanism of Gel-CM on accelerating chronic wound healing. By using techniques and to elucidate the relationship between rapid adipogenesis and early infiltration of M2 macrophages during wound healing. This research is believed to be helpful to build a theoretical basis and provide stable experimental evidence for clinical application of Gel-CM.

慢性创面是迫切需要解决的重大民生问题。SVF/ASCs细胞疗法被认为是慢性创面最有前景的治疗方法之一。前期研究发现创面下脂肪再生在创面愈合过程中发挥重要作用，其机制在于脂肪再生过程伴随着修复性M2型巨噬细胞浸润。进一步的研究显示富集SVF细胞和细胞外基质的脂肪干细胞胶通过诱导快速成脂和M2型巨噬细胞浸润从而加速糖尿病鼠皮肤创面愈合。然而，脂肪干细胞胶存在不能实验室培养和远期保存困难的不足。据此，我们提取了一种富含脂肪干细胞胶相关细胞因子的条件培养基（Gel-CM）。结果显示Gel-CM具备近似于脂肪干细胞胶的促创面下脂肪再生及促创面愈合的能力，且具有保存方便和大规模生产的优势。本研究将紧紧围绕这个发现，对Gel-CM促进慢性创面愈合的机制进行深入探讨，采用多种实验技术，阐明快速成脂、M2巨噬细胞早期浸润在创面愈合中的关系，为Gel-CM的临床应用提供理论基础和实验依据。

慢性创面是迫切需要解决的重大民生问题。SVF/ASCs细胞疗法被认为是慢性创面最有前景的治疗方法之一。我们前期研究发现富集SVF细胞和细胞外基质的脂肪干细胞胶通过诱导快速成脂和M2型巨噬细胞浸润从而加速糖尿病鼠皮肤创面愈合。然而 ，脂肪干细胞胶存在不能实验室培养和远期保存困难的不足。据此，我们提取了一种富含脂肪干细胞胶相关细胞因子的条件培养基（Gel-CM）。本研究对Gel-CM促进慢性创面愈合的机制进行深入探讨。 结果显示Gel-CM富含多种活性因子，在体外可以促进角质形成细胞和成纤维细胞的增殖和迁移；Gel-CM 在体内可加速糖尿病 创面的愈合，提高创面愈合质量,并诱导了脂肪再生,促进成脂相关基因的表达。我们还探究了发现脂肪再生可以加速创面的愈合；成脂洗信号PPARγ的激活可诱导脂肪细胞的再生，并促进M2型巨噬细胞的早期浸润来改善了创面局部炎症。另外，脂肪干细胞胶条件培养基可调控PPARγ的激活，并上调了成脂基因以及抗炎基因的表达，降低促炎基因的表达，从而介导脂肪再生和炎症反应参与创面愈合过程。