Department of Orthopaedics, The General Hospital of Jinan Military, Jinan, China.
Eur Rev Med Pharmacol Sci. 2019 Apr;23(7):2935-2943. doi: 10.26355/eurrev_201904_17573.
To investigate the influences of human umbilical cord mesenchymal stem cell-derived exosomes (hucMSC-exosome) on steroid-induced necrosis of the femoral head (SNFH) and the expressions of vascular endothelial growth factor (VEGF) and bone morphogenetic protein-2 (BMP-2) in rats.
A total of 20 male Sprague-Dawley rats were randomly divided into SNFH group and SNFH + hucMSC-exosome group using a random number table. Prednisolone acetate (24.5 mg/kg) was injected twice a week to establish the rat model of SNFH, and hucMSC-exosome in a certain dose was additionally injected into the marrow cavity in SNFH + hucMSC-exosome group. After 3 weeks, the influences of hucMSC-exosome on the pathological changes and apoptosis of the femoral head in SNFH rats were detected via hematoxylin-eosin (H&E) staining and terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling (TUNEL) staining. In addition, the expressions of cluster of differentiation 31 (CD31), VEGF, and BMP-2 in bone tissues in both groups were detected via immunohistochemical staining, and the messenger ribonucleic acid (mRNA) and protein expression levels of VEGF and BMP-2 in necrotic bone tissues in both groups were detected via Reverse Transcription-Polymerase Chain Reaction (RT-PCR) and Western blotting.
The results of H&E staining revealed that the fibrous callus formation was good, the new trabecular structure was more obvious, the number of vacuum cleft declined, and there were fewer enlarged adipocytes in SNFH + hucMSC-exosome group compared with SNFH group. The results of TUNEL staining showed that the number of apoptotic cells in femoral head tissues was smaller in SNFH + hucMSC-exosome group (p<0.05). According to the results of immunohistochemistry, hucMSC-exosome could increase the expression of vascular endothelial marker CD31 in SNFH rats (p<0.05). Besides, the results of RT-PCR, immunostaining and Western blotting manifested that both the mRNA and protein levels of BMP-2 and VEGF in femoral head tissues were significantly increased in SNFH + hucMSC-exosome group (p<0.05).
HucMSC-exosome can improve SNFH in rats, whose mechanism may be related to the up-regulation of VEGF and BMP-2 by exosomes.
探讨人脐带间充质干细胞来源的外泌体（hucMSC-exosome）对激素诱导性股骨头坏死（SNFH）大鼠及血管内皮生长因子（VEGF）和骨形态发生蛋白-2（BMP-2）表达的影响。
采用随机数字表法将 20 只雄性 Sprague-Dawley 大鼠随机分为 SNFH 组和 SNFH+hucMSC-exosome 组。每周两次注射醋酸泼尼松龙（24.5mg/kg）建立 SNFH 大鼠模型，SNFH+hucMSC-exosome 组在骨髓腔内额外注射一定剂量的 hucMSC-exosome。3 周后，通过苏木精-伊红（H&E）染色和末端脱氧核苷酸转移酶介导的 dUTP 缺口末端标记（TUNEL）染色检测 hucMSC-exosome 对 SNFH 大鼠股骨头病理变化和细胞凋亡的影响。此外，通过免疫组织化学染色检测两组骨组织中 CD31 的表达，通过逆转录-聚合酶链反应（RT-PCR）和 Western blot 检测两组坏死骨组织中 VEGF 和 BMP-2 的信使核糖核酸（mRNA）和蛋白表达水平。
H&E 染色结果显示，SNFH+hucMSC-exosome 组纤维性骨痂形成良好，新生小梁结构更明显，空骨陷窝数量减少，脂肪细胞增大减少。TUNEL 染色结果显示，SNFH+hucMSC-exosome 组股骨头组织中凋亡细胞数量减少（p<0.05）。免疫组织化学结果显示，hucMSC-exosome 可增加 SNFH 大鼠血管内皮标志物 CD31 的表达（p<0.05）。此外，RT-PCR、免疫组化和 Western blot 结果显示，SNFH+hucMSC-exosome 组股骨头组织中 BMP-2 和 VEGF 的 mRNA 和蛋白水平均显著升高（p<0.05）。
hucMSC-exosome 可改善 SNFH 大鼠，其机制可能与外泌体上调 VEGF 和 BMP-2 有关。
