脂肪移植是一种新兴软组织缺损修复方法，如何提高移植脂肪组织成活率是目前的焦点问题。前脂肪细胞成脂分化与提高移植脂肪存活率有密切关系。DNA甲基转移酶（DNMT）执行DNA表观遗传修饰，在前脂肪细胞分化过程中扮演关键角色。有研究表明，前脂肪细胞中DNMT1能维持DNA甲基化，维持前脂肪细胞的干性，DNMT1静默导致脂肪细胞分化加速。同时有报道，丹参酚酸B可抑制DNMT1的表达，导致DNA去甲基化【J Cell Mol Med 2015】。项目组前期研究发现，前脂肪细胞在丹参酚酸B干预下，成脂诱导分化明显增加，显著提高脂肪移植成活率。据此提出假说：丹参酚酸B通过静默DNMT1，抑制成脂相关基因的DNA甲基化，促使前脂肪细胞向脂肪细胞分化。本项目拟通过RNA干扰技术，芯片生物学分析和DNA甲基化研究等手段，研究丹参酚酸B调控DNMT1对成脂分化的影响及作用机制，为提高脂肪移植存活率提供新思路。

Fat transplantation is a new method for repairing soft tissue defects. How to improve the survival rate of transplanted adipose tissue is the current focusing point at present. There is a close relationship between the conversion of preadipocytes into adipocytes and the survival rate of transplanted fat tissue. DNA methyltransferase (DNMT) plays an important role in the differentiation of preadipocytes by performing DNA epigenetic modification. Studies have shown that DNMT1 can maintain DNA methylation in preadipocytes, maintain the stem cell characteristics of preadipocytes, DNMT1 silence led to accelerated adipocyte differentiation. At the same time, it has been reported that Salvianolic acid B can inhibit the expression of DNMT1, leading to DNA demethylation (J Cell Mol Med 2015). In the previous study, it was found that the induction of adipocyte differentiation was significantly increased in the presence of Salvianolic Acid B, which could significantly increase the survival rate of fat transplantation. Based on this, The project team proposed a hypothesis that Salvianolic Acid B inhibits DNA methylation by silencing DNMT1, which promotes the differentiation of preadipocytes into adipocytes. This project is proposed by the means of RNA interference technology, chip biological analysis and DNA methylation researching to study the effect of Salvianolic Acid B on regulating DNMT on adipogenic differentiation and its mechanism, in order to provide new thought on the improvement of fat transplantation survival rate.