Han Hu, Liu Lijuan
Department of Rehabilitation, The First People's Hospital of Jingmen, No. 67 Xiangshan Dadao, Dongbao District, Jingmen 448000, Hubei, China.
Open Life Sci. 2021 Apr 21;16(1):384-394. doi: 10.1515/biol-2021-0037. eCollection 2021.
Osteoarthritis (OA) is a common chronic joint disease. This study aimed to explore the function of long noncoding RNA taurine-upregulated gene 1 (TUG1) in the progression and initiation of OA. Levels of TUG1, microRNA-320c (miR-320c) and fucosyltransferase 4 (FUT4) were examined via quantitative reverse transcriptase polymerase chain reaction (qRT-PCR). 3-(4,5-Dimethyl-2-thiazolyl)-2,5-diphenyl-2--tetrazolium bromide and flow cytometry assays were used to detect cell viability and apoptosis, respectively. The expression of relative proteins was measured using Western blot. The interaction between miR-320c and TUG1 or FUT4 was confirmed utilizing dual-luciferase reporter and RNA immunoprecipitation assays. In this study, levels of TUG1 and FUT4 were distinctly upregulated, but miR-320c level significantly decreased in OA tissues and chondrocytes derived from OA tissues as well as in IL-1β-stimulated C28/I2 cells. Mechanically, TUG1 sponged miR-320c and miR-320c targeted FUT4. In addition, TUG1 knockdown accelerated cell proliferation and repressed apoptosis and extracellular matrix (ECM) degradation in IL-1β-induced C28/I2 cells, whereas these effects of TUG1 deletion were rescued by either miR-320c inhibitor or FUT4 upregulation. Meanwhile, TUG1 sponged miR-320c to regulate FUT4 expression in IL-1β-induced C28/I2 cells. Collectively, TUG1 modulated cell proliferation, apoptosis and ECM degradation in IL-1β-induced C28/I2 cells via the miR-320c/FUT4 axis, providing a new insight into the OA treatment.
骨关节炎（OA）是一种常见的慢性关节疾病。本研究旨在探讨长链非编码RNA牛磺酸上调基因1（TUG1）在OA进展和发病中的作用。通过定量逆转录聚合酶链反应（qRT-PCR）检测TUG1、微小RNA-320c（miR-320c）和岩藻糖基转移酶4（FUT4）的水平。分别采用3-（4,5-二甲基-2-噻唑基）-2,5-二苯基-2-溴化四氮唑和流式细胞术检测细胞活力和凋亡。使用蛋白质印迹法检测相关蛋白的表达。利用双荧光素酶报告基因和RNA免疫沉淀试验证实miR-320c与TUG1或FUT4之间的相互作用。在本研究中，OA组织、源自OA组织的软骨细胞以及白细胞介素-1β刺激的C28/I2细胞中，TUG1和FUT4水平明显上调，但miR-320c水平显著降低。机制上，TUG1可吸附miR-320c，而miR-320c靶向FUT4。此外，敲低TUG1可促进白细胞介素-1β诱导的C28/I2细胞增殖，抑制细胞凋亡和细胞外基质（ECM）降解，而miR-320c抑制剂或FUT4上调可挽救TUG1缺失的这些作用。同时，在白细胞介素-1β诱导的C28/I2细胞中，TUG1吸附miR-320c以调节FUT4表达。总体而言，TUG1通过miR-320c/FUT4轴调节白细胞介素-1β诱导的C28/I2细胞的增殖、凋亡和ECM降解，为OA治疗提供了新的见解。
