Nie Ping, Li Yao, Suo Hairui, Jiang Ning, Yu Dedong, Fang Bing
Center of Cranio-facial Orthodontics, Department of Oral and Cranio-maxillofacial Surgery, Shanghai Ninth People's Hospital, College of Stomatology, Shanghai Jiao Tong University School of Medicine, Shanghai 200011, China.
National Clinical Research Center for Oral Diseases, Shanghai Key Laboratory of Stomatology & Shanghai Research Institute of Stomatology, Shanghai 200011, China.
ACS Biomater Sci Eng. 2019 Oct 14;5(10):5255-5265. doi: 10.1021/acsbiomaterials.9b00618. Epub 2019 Sep 17.
Mesenchymal stem cells (MSCs) are progenitors of chondrocytes and could be used as a potential therapy for cartilage defects in diarthrodial joints. However, promoting chondrogenic differentiation of MSCs remains a daunting challenge. As a small molecular drug, dasatinib can promote MSC differentiation, although the exact mechanisms of chondrogenic differentiation are unclear. In this study, the differentiation of MSCs into osteoblasts, adipocytes, and chondrocytes was assessed by the protein and mRNA levels of osteoblast- and chondrocyte-related proteins using western blotting and real-time polymerase chain reaction, respectively. MSCs were induced to differentiate into chondrocytes or osteoblasts with or without dasatinib in vitro. The effects of dasatinib on cartilage regeneration were also assessed in vivo in a rabbit model of full-thickness cartilage defects using methacrylate gelatin hydrogel as scaffolds. Dasatinib promoted chondrogenic differentiation and inhibited osteogenic differentiation of MSCs. Furthermore, dasatinib significantly inhibited the expression of YAP and TAZ and the phosphorylation of Src, but it enhanced serine phosphorylation of YAP during the chondrogenic differentiation of MSCs in vitro. Inhibition of the Hippo pathway using XMU-MP-1 dramatically suppressed the serine phosphorylation of YAP and chondrogenic differentiation of MSCs. Moreover, we confirmed that the sustained release of dasatinib from the hydrogel promoted rabbit cartilage repair. The results demonstrated that dasatinib might promote chondrogenic differentiation of MSCs via the Src/Hippo-YAP signaling pathway and that hydrogel sustained-release dasatinib had a certain effect on the repair of cartilage defects.
间充质干细胞（MSCs）是软骨细胞的祖细胞，可作为治疗滑膜关节软骨缺损的潜在疗法。然而，促进MSCs的软骨生成分化仍然是一项艰巨的挑战。作为一种小分子药物，达沙替尼可以促进MSCs分化，尽管软骨生成分化的确切机制尚不清楚。在本研究中，分别使用蛋白质印迹法和实时聚合酶链反应，通过成骨细胞和软骨细胞相关蛋白的蛋白质和mRNA水平评估MSCs向成骨细胞、脂肪细胞和软骨细胞的分化。在体外，有或没有达沙替尼的情况下，诱导MSCs分化为软骨细胞或成骨细胞。还使用甲基丙烯酸明胶水凝胶作为支架，在兔全层软骨缺损模型中体内评估达沙替尼对软骨再生的影响。达沙替尼促进了MSCs的软骨生成分化并抑制了其成骨分化。此外，达沙替尼显著抑制YAP和TAZ的表达以及Src的磷酸化，但在体外MSCs软骨生成分化过程中增强了YAP的丝氨酸磷酸化。使用XMU-MP-1抑制Hippo通路可显著抑制YAP的丝氨酸磷酸化和MSCs的软骨生成分化。此外，我们证实水凝胶中达沙替尼的缓释促进了兔软骨修复。结果表明，达沙替尼可能通过Src/Hippo-YAP信号通路促进MSCs的软骨生成分化，并且水凝胶缓释达沙替尼对软骨缺损的修复有一定作用。
