Exosomes derived from Wharton's jelly of human umbilical cord mesenchymal stem cells reduce osteocyte apoptosis in glucocorticoid-induced osteonecrosis of the femoral head in rats via the miR-21-PTEN-AKT signalling pathway

作者：Mingjie Kuang, Ying Ping Huang, Xige Zhao, Rui Zhang, Jianxiong Ma, Da-Chuan Wang, Xinlong Ma · 发表于：International Journal of Biological Sciences · 年份：2019 · DOI：10.7150/ijbs.32262 · 被引用次数：118 · 研究领域：Bone and Joint Diseases、Extracellular vesicles in disease、MicroRNA in disease regulation

Purpose: Glucocorticoid-induced osteonecrosis of the femoral head (GIONFH) is a common disease after long-term or high-dose glucocorticoid use.The pathogenesis of GIONFH is still controversial, and abnormal bone metabolism caused by glucocorticoids may be one of the important factors.Exosomes, owing to their positive effect on bone repair, show promising therapeutic effects on bone-related diseases.In this study, we hypothesised that exosomes reduce osteocyte apoptosis in rat GIONFH via the miR-21-PTEN-AKT signalling pathway.Methods: To evaluate the effects of exosomes in GIONFH, a dexamethasone-treated or exosome-treated in vitro cell model and a methylprednisolone-treated in vivo rat model were set up.In vitro, a CCK-8 assay and 5-ethynyl-2′-deoxyuridine staining were performed to evaluate the proliferation of osteocytes.Further, a terminal deoxynucleotidyl transferase dUTP nick end labelling (TUNEL) assay, annexin V-fluorescein isothiocyanate-propidium iodide staining, and western blotting were conducted to evaluate the apoptosis of osteocytes.In vivo, we used micro-computed tomography and histological and immunohistochemical analyses to assess the effects of exosomes.Moreover, the mechanism of exosome action on osteocyte apoptosis through the miR-21-PTEN-AKT pathway was investigated by high-throughput RNA sequencing, fluorescence in situ hybridisation, luciferase reporter assays, and western blotting.Results: High-throughput RNA sequencing results showed that the AKT sign...