Normandie Université, UNICAEN, EA7451, BioConnecT, Caen, France.
CHU, Service de Rhumatologie, Caen, France.
Lab Invest. 2020 Jan;100(1):64-71. doi: 10.1038/s41374-019-0303-0. Epub 2019 Aug 13.
Osteoarthritis (OA) is characterized by cartilage degradation, inflammation, and hypertrophy. Therapies are mainly symptomatic and aim to manage pain. Consequently, medical community is waiting for new treatments able to reduce OA process. This study aims to develop an in vitro simple OA model useful to predict drug ability to reduce cartilage hypertrophy. Human primary OA chondrocytes were incubated with transforming growth factor beta 1 (TGF-β1). Hypertrophy was evaluated by Runx2, type X collagen, MMP13, and VEGF expression. Cartilage anabolism was investigated by Sox9, aggrecan, type II collagen, and glycosaminoglycan expression. In chondrocytes, TGF-β1 increased expression of hypertrophic genes and activated canonical WNT pathway, while it decreased dramatically cartilage anabolism, suggesting that this treatment could mimic some OA features in vitro. Additionally, EZH2 inhibition, that has been previously reported to decrease cartilage hypertrophy and reduce OA development in vivo, attenuated COL10A1 and MMP13 upregulation and SOX9 downregulation induced by TGF-β1 treatment. Similarly, pterosin B (an inhibitor of Sik3), and DMOG (a hypoxia-inducible factor prolyl hydroxylase which mimicks hypoxia), repressed the expression of hypertrophy markers in TGF-β stimulated chondrocytes. In conclusion, we established an innovative OA model in vitro. This cheap and simple model will be useful to quickly screen new drugs with potential anti-arthritic effects, in complementary to current inflammatory models, and should permit to accelerate development of efficient treatments against OA able to reduce cartilage hypertrophy.
骨关节炎（OA）的特征为软骨降解、炎症和肥大。治疗方法主要是对症治疗，旨在缓解疼痛。因此，医学界正在等待新的治疗方法，以减少 OA 进程。本研究旨在开发一种简单的体外 OA 模型，用于预测药物减少软骨肥大的能力。将人原代 OA 软骨细胞与转化生长因子 β1（TGF-β1）孵育。通过 Runx2、型 X 胶原、MMP13 和 VEGF 的表达来评估肥大。通过 Sox9、聚集蛋白聚糖、型 II 胶原和糖胺聚糖的表达来研究软骨合成代谢。在软骨细胞中，TGF-β1 增加了肥大基因的表达并激活了经典的 WNT 通路，同时大大降低了软骨合成代谢，表明这种处理可以在体外模拟一些 OA 特征。此外，先前已报道抑制 EZH2 可减少软骨肥大并减少体内 OA 的发展，抑制 TGF-β1 处理引起的 COL10A1 和 MMP13 上调和 SOX9 下调。同样，pterosin B（Sik3 的抑制剂）和 DMOG（模拟缺氧的缺氧诱导因子脯氨酰羟化酶）抑制了 TGF-β 刺激的软骨细胞中肥大标志物的表达。总之，我们建立了一种创新的体外 OA 模型。这种廉价且简单的模型将有助于快速筛选具有潜在抗关节炎作用的新药，与当前的炎症模型互补，并有助于加速开发能够减少软骨肥大的有效 OA 治疗方法。
