Chijimatsu Ryota, Kobayashi Masato, Ebina Kosuke, Iwahashi Toru, Okuno Yosuke, Hirao Makoto, Fukuhara Atsunori, Nakamura Norimasa, Yoshikawa Hideki
Graduate School of Medicine, Orthopaedic Surgery, Osaka University, 2-2 Yamadaoka, Suita, Osaka, Japan.
Graduate School of Medicine, Metabolic Medicine, Osaka University, 2-2 Yamadaoka, Suita, Osaka, Japan.
Cytotechnology. 2018 Apr;70(2):819-829. doi: 10.1007/s10616-018-0191-y. Epub 2018 Jan 19.
Human synovial mesenchymal stem cells (hSMSCs) are a promising cell source for cartilage regeneration because of their superior chondrogenic potential in vitro. This study aimed to further optimize the conditions for inducing chondrogenesis of hSMSCs, focusing on the dose of dexamethasone in combination with transforming growth factor-β3 (TGFβ3) and/or bone morphogenetic protein-2 (BMP2). When hSMSCs-derived aggregates were cultured with TGFβ3, dexamethasone up to 10 nM promoted chondrogenesis, but attenuated it with heterogeneous tissue formation when used at concentrations over than 100 nM. On the other hands, BMP2-induced chondrogenesis was remarkably disturbed in the presence of more than 10 nM dexamethasone along with unexpected adipogenic differentiation. In the presence of both TGFβ3 and BMP2, dexamethasone dose dependently promoted cartilaginous tissue formation as judged by tissue volume, proteoglycan content, and type 2 collagen expression, whereas few adipocytes were detected in the formed tissue when cultures were supplemented with over 100 nM dexamethasone. Even in chondrogenic conditions, dexamethasone thus affected hSMSCs differentiation not only toward chondrocytes, but also towards adipocytes dependent on the dose and combined growth factor. These findings have important implications regarding the use of glucocorticoids in in vitro tissue engineering for cartilage regeneration using hSMSCs.
人滑膜间充质干细胞（hSMSCs）因其在体外具有卓越的软骨生成潜能，是软骨再生中一种很有前景的细胞来源。本研究旨在进一步优化hSMSCs软骨生成诱导条件，重点关注地塞米松与转化生长因子-β3（TGFβ3）和/或骨形态发生蛋白-2（BMP2）联合使用时的剂量。当hSMSCs来源的聚集体与TGFβ3一起培养时，高达10 nM的地塞米松可促进软骨生成，但当浓度超过100 nM时，会因异质性组织形成而使其减弱。另一方面，在存在超过10 nM地塞米松的情况下，BMP2诱导的软骨生成会受到显著干扰，并伴有意外的脂肪生成分化。在同时存在TGFβ3和BMP2的情况下，根据地塞米松的剂量不同，软骨组织形成会受到促进，这通过组织体积、蛋白聚糖含量和II型胶原蛋白表达来判断，而当培养基中添加超过100 nM地塞米松时，在形成的组织中几乎检测不到脂肪细胞。因此，即使在软骨生成条件下，地塞米松也会影响hSMSCs的分化，不仅朝着软骨细胞方向，还会根据剂量和联合生长因子朝着脂肪细胞方向分化。这些发现对于在使用hSMSCs进行软骨再生的体外组织工程中使用糖皮质激素具有重要意义。
