Dows Institute for Dental Research, College of Dentistry, University of Iowa, Iowa City, IA 52242, USA.
Steroids. 2012 Jan;77(1-2):132-7. doi: 10.1016/j.steroids.2011.10.017. Epub 2011 Nov 7.
Although exogenous glucocorticoids (GC) play a role in the regulation of bone marrow mesenchymal stem/stromal cells (MSCs) proliferation and differentiation, the function of endogenous GC is not well understood. The purpose of this study was to investigate the effect of the blockage of endogenous GC using RU486, an antagonist of the glucocorticoid receptor, on the in vitro proliferation and differentiation capabilities of human MSCs. We quantitatively measured cell proliferation of human MSCs after treatment with increasing concentrations of RU486. We also evaluated multiple MSC differentiation capabilities, as well as the expression of stemness and senescence genes after proliferation of these human cells in vitro in the presence of RU486 at 10(-8)M. It was observed that RU486 treatment significantly increases the proliferation of human MSCs, although the optimal dose of RU486 for this increase in proliferation differs depending on the gender of the MSC donor. This improvement in MSC proliferation with RU486 treatment was higher in MSCs from male donors than that from females. No effect of RU486 on MSC proliferation was observed in a steroid-free medium. RU486 pretreatment significantly increased the expression of mRNA for alkaline phosphatase in human MSCs and the mRNA expression of osteocalcin of these cells up-regulated earlier after their exposure to osteogenic differentiation medium. Although no statistical significance in terms of chondrogenic differentiation markers was detected, mRNA expression for aggrecan and collagen type 2 were higher in a majority of the RU486-pretreated donor MSCs than their untreated controls. No significant difference in terms of MSC adipogenic differentiation capabilities were observed after RU486 treatment. RU486 treatment up-regulated the expressions of FGF-2 and Sox-11 in human MSCs. These results indicate that blockage of endogenous GCs may be developed as a novel approach to effectively improve the proliferation and osteochondral differentiation capabilities of human MSCs for potential clinical applications. Additional studies will be required to determine the potential long-term effects of RU486 treatment on these bone marrow cells.
尽管外源性糖皮质激素（GC）在调节骨髓间充质干细胞（MSCs）增殖和分化中发挥作用，但内源性 GC 的功能尚不清楚。本研究旨在探讨使用 RU486（糖皮质激素受体拮抗剂）阻断内源性 GC 对人 MSCs 体外增殖和分化能力的影响。我们定量测量了人 MSCs 在不同浓度 RU486 处理后的细胞增殖情况。我们还评估了多种 MSC 分化能力，以及在 RU486 存在下，这些人细胞在体外增殖后的干性和衰老基因的表达。结果表明，RU486 处理可显著增加人 MSCs 的增殖，尽管 RU486 促进增殖的最佳剂量因 MSC 供体的性别而异。与女性供体相比，RU486 处理对男性供体 MSCs 增殖的促进作用更高。在无类固醇培养基中未观察到 RU486 对 MSC 增殖的影响。RU486 预处理可显著增加人 MSCs 碱性磷酸酶 mRNA 的表达，并上调这些细胞在暴露于成骨分化培养基后更早的骨钙素 mRNA 表达。尽管在软骨分化标志物方面未检测到统计学意义，但大多数 RU486 预处理供体 MSC 的聚集蛋白聚糖和 II 型胶原的 mRNA 表达更高。RU486 处理后，MSC 成脂分化能力无显著差异。RU486 处理可上调人 MSCs 中 FGF-2 和 Sox-11 的表达。这些结果表明，阻断内源性 GCs 可能成为一种有效提高人 MSCs 增殖和成骨软骨分化能力的新方法，具有潜在的临床应用价值。需要进一步研究以确定 RU486 处理对这些骨髓细胞的潜在长期影响。
