Wang Tiansheng, Teng Shoufa, Zhang Yingxia, Wang Fa, Ding Haijiao, Guo Li
Department of Orthopedics, 463 Hospital of PLA, Shenyang, Liaoning 110042, P.R. China.
Exp Ther Med. 2017 Feb;13(2):669-675. doi: 10.3892/etm.2016.3991. Epub 2016 Dec 22.
Steroids are known to inhibit osteogenic differentiation and decrease bone formation in mesenchymal stem cells (MSCs), while concomitantly inducing steroid-induced avascular necrosis of the femoral head (SANFH). The aim of the present study was to evaluate the function of MSCs on differentiation in SANFH and investigate the pathobiological mechanisms underlying SANFH in a rabbit model. MSCs in the control, trauma-induced ANFH (TANFH) and SANFH groups were incubated with low-glucose complete Dulbeccos modified Eagles medium containing 10% fetal bovine serum. A number of adipocytes in the MSCs were stained with Sudan III and counted using a light microscope. The mRNA and protein expression levels of the adipose-specific 422 (AP2), peroxisome proliferator-activated receptor-γ (PPARγ), RUNX2, collagen type I (Col I) and miR-103 in the MSCs were determined using quantitative polymerase chain reaction and western blot analysis, respectively. In addition, the activities of osteocalcin (OC), alkaline phosphatase (ALP) and triglyceride (TG) in MSCs were analyzed using radioimmunoassay and determination kits. In the MSCs of the SANFH group, the mRNA and protein expression levels of AP2 and PPARγ were increased, while those of RUNX2 and Col I were reduced. Furthermore, the levels of OC and ALP activity in the MSCs of the SANFH group were decreased, and the activity of TG in the MSCs of the SANFH group was increased. In addition, the expression of miR-103 in the MSCs of the SANFH group was elevated. Following routine culture of the MSCs for 3 weeks, the number of adipocytes among the MSC population of the SANFH group was increased. Therefore, the results of the present study suggest that the osteogenic differentiation of MSCs in the SANFH was mitigated, while fat differentiation was promoted, which provides a novel explanation for the pathological changes associated with SANFH.
已知类固醇会抑制间充质干细胞（MSCs）的成骨分化并减少骨形成，同时引发类固醇诱导的股骨头缺血性坏死（SANFH）。本研究的目的是评估MSCs在SANFH中的分化功能，并研究兔模型中SANFH的病理生物学机制。将对照组、创伤性股骨头缺血性坏死（TANFH）组和SANFH组的MSCs与含10%胎牛血清的低糖完全杜氏改良伊格尔培养基一起培养。用苏丹III对MSCs中的一些脂肪细胞进行染色，并用光学显微镜计数。分别采用定量聚合酶链反应和蛋白质印迹分析测定MSCs中脂肪特异性422（AP2）、过氧化物酶体增殖物激活受体γ（PPARγ）、RUNX2、I型胶原（Col I）和miR-103的mRNA和蛋白质表达水平。此外，采用放射免疫分析法和检测试剂盒分析MSCs中骨钙素（OC）、碱性磷酸酶（ALP）和甘油三酯（TG）的活性。在SANFH组的MSCs中，AP2和PPARγ的mRNA和蛋白质表达水平升高，而RUNX2和Col I的表达水平降低。此外，SANFH组MSCs中OC和ALP活性水平降低，而SANFH组MSCs中TG活性升高。此外，SANFH组MSCs中miR-103的表达升高。MSCs常规培养3周后，SANFH组MSCs群体中的脂肪细胞数量增加。因此，本研究结果表明，SANFH中MSCs的成骨分化受到抑制，而脂肪分化得到促进，这为与SANFH相关的病理变化提供了新的解释。
