Department of Orthopedic Surgery, State Key Laboratory of Complex Severe and Rare Diseases, Peking Union Medical College Hospital, Chinese Academy of Medical Science and Peking Union Medical College, Beijing 100730, China.
School of Basic Medicine, Fourth Military Medical University, Xi'an 710032, China.
Int Immunopharmacol. 2021 Nov;100:108138. doi: 10.1016/j.intimp.2021.108138. Epub 2021 Sep 9.
Long noncoding RNAs (lncRNAs) regulate the occurrence and development of osteoarthritis (OA), whereas the biological roles and mechanisms of the lncRNA THUMPD3-AS1 (THUMPD3 antisense RNA 1) in OA remain still unclear. This study described the role and molecular mechanism of lncRNA THUMPD3-AS1 in regulating OA biology.
The knee normal and OA cartilage tissues from ten participants were sequenced to reveal the differentially expressed lncRNAs. The interleukin (IL)-1β-stimulated C28/I2 cell served as OA cells. Flow cytometry assays, Western blot, enzyme-linked immunosorbent assays were used for our experiments.
The results revealed that lncRNA THUMPD3-AS1 was downregulated in OA cartilage tissues and IL-1β-stimulated chondrocyte cell line. Overexpression of lncRNA THUMPD3-AS1 alleviated cell apoptosis and facilitated inflammatory responses, whereas knockdown had opposite effects. LncRNA THUMPD3-AS1 markedly increased the cyclin E2, cyclin-dependent kinase 4, B-cell lymphoma 2, tumor necrosis factor-α, nitric oxide, and IL-6 levels, and decreased the caspase-3 level. Furthermore, the target proteins of phosphorylation were identified as nuclear factor-κB p65 and mitogen-activated protein kinase p38, which could be indirectly suppressed by lncRNA THUMPD3-AS1 knockdown.
Our findings highlight the different effects of lncRNA THUMPD3-AS1 on cell apoptosis and inflammatory response, which extend the multiple functions of lncRNA epigenetics in OA biology.
长链非编码 RNA（lncRNA）调控骨关节炎（OA）的发生发展，然而 lncRNA THUMPD3-AS1（THUMPD3 反义 RNA 1）在 OA 中的生物学作用和机制仍不清楚。本研究描述了 lncRNA THUMPD3-AS1 在调控 OA 生物学中的作用和分子机制。
对 10 名参与者的正常膝关节和 OA 软骨组织进行测序，以揭示差异表达的 lncRNA。用白细胞介素（IL）-1β刺激的 C28/I2 细胞作为 OA 细胞。采用流式细胞术、Western blot、酶联免疫吸附试验进行实验。
结果表明，lncRNA THUMPD3-AS1 在 OA 软骨组织和 IL-1β刺激的软骨细胞系中表达下调。lncRNA THUMPD3-AS1 的过表达可减轻细胞凋亡并促进炎症反应，而敲低则有相反的作用。lncRNA THUMPD3-AS1 可显著增加 cyclin E2、cyclin-dependent kinase 4、B 细胞淋巴瘤 2、肿瘤坏死因子-α、一氧化氮和白细胞介素-6 的水平，降低 caspase-3 的水平。此外，磷酸化的靶蛋白被鉴定为核因子-κB p65 和丝裂原活化蛋白激酶 p38，它们可被 lncRNA THUMPD3-AS1 敲低间接抑制。
本研究结果突出了 lncRNA THUMPD3-AS1 对细胞凋亡和炎症反应的不同影响，这扩展了 lncRNA 表观遗传学在 OA 生物学中的多种功能。
