Shanghai Key Laboratory of Orthopaedic Implants, Department of Orthopaedics, Shanghai Ninth People's Hospital, Shanghai Jiao Tong University, School of Medicine, 639 Zhizaoju Road, Shanghai 200011, People's Republic of China.
Biochem Biophys Res Commun. 2011 Oct 22;414(2):412-8. doi: 10.1016/j.bbrc.2011.09.103. Epub 2011 Sep 28.
Mesenchymal stem cells (MSCs) are multi-potent, and the chondrogenesis of MSCs is affected by mechanical stimulation. The aim of this study was to investigate, using a rotary cell culture system (RCCS) bioreactor, the effects of microgravity on the chondrogenic differentiation of human adipose-derived MSCs (ADSCs), which were cultured in pellets with or without the chondrogenic growth factor TGF-β1. In addition, we evaluated the role of the p38 MAPK pathway in this process. The real-time PCR and histological results show that microgravity has a synergistic effect on chondrogenesis with TGF-β1. The p38 MAPK pathway was activated by TGF-β1 alone and was further stimulated by microgravity. Inhibition of p38 activity with SB203580 suppressed chondrocyte-specific gene expression and matrix production. These findings suggest that the p38 MAPK signal acts as an essential mediator in the microgravity-induced chondrogenesis of ADSCs.
间充质干细胞（MSCs）是多能的，并且 MSCs 的软骨形成受机械刺激的影响。本研究的目的是使用旋转细胞培养系统（RCCS）生物反应器，研究微重力对在含有或不含有软骨形成生长因子 TGF-β1 的微球中培养的人脂肪来源间充质干细胞（ADSCs）的软骨分化的影响。此外，我们评估了 p38 MAPK 途径在这个过程中的作用。实时 PCR 和组织学结果表明，微重力与 TGF-β1 对软骨形成具有协同作用。TGF-β1 单独激活 p38 MAPK 途径，微重力进一步刺激其激活。用 SB203580 抑制 p38 活性可抑制软骨细胞特异性基因表达和基质生成。这些发现表明，p38 MAPK 信号在 ADSC 的微重力诱导的软骨形成中作为必需的介质发挥作用。
