Kim Yang Woo, Min Hyung Jun, Choi Rak Jun, Lee Dong Hun, Cheon Young Woo
From the Department of Plastic and Reconstructive Surgery, Gil Medical Center, Gachon University College of Medicine; and the Lamiche Plastic Surgery Clinic.
Plast Reconstr Surg. 2018 Oct;142(4):927-938. doi: 10.1097/PRS.0000000000004814.
Adipose-derived stem cells are used to enhance fat graft survival. However, their mechanism of action when grafted is controversial. The grafted cells can be replaced by connective tissue or survive at the recipient site and differentiate. Insulin is a powerful agent used to induce their differentiation to adipocytes. The purpose of this study was to elucidate the fate of grafted adipose-derived stem cells in nonvascularized fat grafts with or without insulin.
Fat was harvested from a female human donor who had undergone reduction mammaplasty. The authors also isolated and cultured adipose-derived stem cells expressing green fluorescent protein from transgenic Sprague-Dawley rats. Injection of free fat graft, the adipose-derived stem cells, phosphate-buffered saline, and insulin was performed on the four paravertebral points of the back of each mouse (n = 30) as follows: group A (control group) received adipose tissue and phosphate-buffered saline; group B received adipose tissue and adipose-derived stem cells; group C received adipose tissue, adipose-derived stem cells, and phosphate-buffered saline; and group D received adipose tissue, adipose-derived stem cells, and insulin. Green fluorescent protein expression was evaluated using an in vivo imaging system. The volume of transplanted fat was evaluated at 8 weeks after graft with six histologic parameters. The fat graft was immunostained with green fluorescent protein, 4',6-diamidino-2-phenylindole, and perilipin. Statistical analysis was performed using a one-way analysis of variance test.
The fat graft volume was significantly higher in group D (p < 0.05). Histologic examination revealed reduced fibrosis and increased cysts, vacuoles, integrity, and vascularity in group D. The green fluorescent protein and perilipin co-positive area was more apparent in group D compared with groups B and C.
Insulin could enhance the survival and differentiation of adipose-derived stem cells in nonvascularized fat grafts.
脂肪来源干细胞被用于提高脂肪移植的存活率。然而，其移植后的作用机制存在争议。移植的细胞可被结缔组织替代，或在受体部位存活并分化。胰岛素是一种用于诱导其向脂肪细胞分化的强效剂。本研究的目的是阐明在有或无胰岛素情况下，移植的脂肪来源干细胞在非血管化脂肪移植中的命运。
从一名接受过缩乳手术的女性人类供体获取脂肪。作者还从转基因Sprague-Dawley大鼠中分离并培养了表达绿色荧光蛋白的脂肪来源干细胞。在每只小鼠（n = 30）背部的四个椎旁点进行游离脂肪移植、脂肪来源干细胞、磷酸盐缓冲盐水和胰岛素的注射，如下：A组（对照组）接受脂肪组织和磷酸盐缓冲盐水；B组接受脂肪组织和脂肪来源干细胞；C组接受脂肪组织、脂肪来源干细胞和磷酸盐缓冲盐水；D组接受脂肪组织、脂肪来源干细胞和胰岛素。使用体内成像系统评估绿色荧光蛋白的表达。在移植后8周，用六个组织学参数评估移植脂肪的体积。脂肪移植用绿色荧光蛋白、4',6-二脒基-2-苯基吲哚和周脂素进行免疫染色。使用单因素方差分析进行统计分析。
D组的脂肪移植体积显著更高（p < 0.05）。组织学检查显示，D组的纤维化减少，囊肿、空泡、完整性和血管生成增加。与B组和C组相比，D组中绿色荧光蛋白和周脂素共阳性区域更明显。
胰岛素可提高非血管化脂肪移植中脂肪来源干细胞的存活率和分化率。
