Exosomes derived from bone marrow mesenchymal stem cells promote angiogenesis of fat grafting through Notch signaling pathway
10.3760/cma.j.cn114453-20210426-00185
- VernacularTitle:骨髓间充质干细胞外泌体通过Notch信号通路促进移植脂肪血管化的实验研究
- Author:
Juanli DANG
1
;
Zhou YU
;
Lin CHEN
;
Kai WANG
;
Xiangke RONG
;
Han PENG
;
Chenggang YI
Author Information
1. 空军军医大学第一附属医院整形外科，西安 710032
- Keywords:
Adipose tissue;
Transplantation, heterologous;
Stem cells;
Bone marrow;
Exosomes;
Neovascularization;
Notch signaling pathway;
Fat grafting
- From:
Chinese Journal of Plastic Surgery
2021;37(10):1114-1121
- CountryChina
- Language:Chinese
-
Abstract:
Objective:The study aimed to investigate the effect of exosomes derived from bone marrow mesenchymal stem cells (BMSC-Exo) in promoting angiogenesis of fat grafts by regulating Notch signaling pathway.Methods:Fat from the abdomen of a 30-year-old healthy female who received liposuction in the Department of Plastic Surgery of the First Affiliated Hospital of Air Force Military Medical University in August 2020 was collected. Fat transplantation models were established using 12 BALB/c nude mice, with 0.5 ml of processed fat particles injected into the left and right sides of the backs. 100 μl BMSC-Exo (50 μg) was injected into the left side of the back of nude mice once per week for 4 weeks after fat grafting, which was the exosome group. The right side of the back was injected with 100 μl of phosphate-buffered saline at the same time points for 4 weeks after fat grafting, which was the control group. The following items were observed: (1) Fat grafts were collected and weighed at 4 weeks and 8 weeks after transplantation, the retention rate was calculated. (2) HE staining and immunofluorescence staining of Perilipin A was used to visualize the structure and integrity of adipocytes at 8 weeks after transplantation. (3) At 8 weeks after transplantation, immunohistochemical staining was used to detect CD31 positive cells, calculate micro vessel density, detect Notch1 and Notch4 positive cells and calculate the proportion of positive area.(4) At 8 weeks after transplantation, the relative expressions levels of Notch1, Notch4 and VEGF mRNA in fat grafts were detected by real-time fluorescence quantitative PCR. The data were analyzed by Graphpad Prism 8.0. T-test was used for comparison between groups. P<0.05 indicated the difference was statistically significant. Results:(1) At 4 and 8 weeks after transplantation, the retention rates of adipose tissue wet weight in the control group were (41.15±9.68)% and (34.30±6.45)% respectively. The results in the exosome group were (61.77±10.98)% and (55.93±5.89)%, which were higher than those in the control group ( P<0.05). (2) At 8 weeks after transplantation, the structural integrity of adipocytes in the exosome group was better than the control group, with more neovascularization. There were more intact Perilipin A positive adipocytes in the exosome group and less in the control group. (3) At 8 weeks after transplantation, the density of micro vessels in the control group was 4.67±0.57, which was significantly lower than that in the exosome group (13.00±2.00, P<0.05). The proportion of Notch1 and Notch4 positive area per visual field in the control group was lower than that in the exosome group [(0.53±0.28)% vs. (1.67±0.11)%, (0.11±0.06)% vs. (1.20±0.24)%, P<0.05]. (4) The mRNA expression levels of Notch1, Notch4 and VEGF were 1.53±0.20, 1.50±0.26 and 2.56±0.55 in the exosome group, which were significantly higher than those in the control group (1.00+ 0.00) ( P<0.05). Conclusions:BMSC-Exo may promote angiogenesis and improve retention rate of transplanted fat grafts through the elevation of VEGF expression and the activation of Notch signaling pathway.
