Department of Joint and Sports Medicine, The First People's Hospital of Shaoguan City, No.3 Dongdi South Road, Zhenjiang District, Shaoguan, 512000, Guangdong, People's Republic of China.
J Orthop Surg Res. 2022 Jun 10;17(1):304. doi: 10.1186/s13018-022-03202-5.
This study was conducted to investigate the effect of long non-coding RNA (lncRNA) Gm37494 on osteoarthritis (OA) and its related molecular mechanism.
The cartilage tissues were obtained from OA patients, and an OA mouse model was induced by the destabilization of the medial meniscus, followed by measurement of Gm37494, microRNA (miR)-181a-5p, GABRA1 mRNA, and the encoded GABAR protein expression. Thereafter, a cellular model was induced by interleukin-1β (IL-1β) treatment in chondrocytes, followed by ectopic and silencing experiments. Chondrocyte proliferation was detected by CCK-8 and EdU assays, chondrocyte apoptosis by flow cytometry and western blot, and the levels of inflammatory factors by ELISA. The binding of Gm37494 to miR-181a-5p was evaluated by dual-luciferase reporter gene and RIP assays, and that of GABRA1 to miR-181a-5p by dual-luciferase reporter gene and RNA pull-down assays.
OA patients and mice had decreased GABRA1 mRNA and GABAR protein levels and elevated miR-181a-5p expression in cartilage tissues. Additionally, Gm37494 was poorly expressed in OA mice. Mechanistically, Gm37494 directly bound to and inversely modulated miR-181a-5p that negatively targeted GABRA1. In IL-1β-induced chondrocytes, Gm37494 overexpression enhanced cell proliferation and suppressed cell apoptosis and inflammation, whereas further miR-181a-5p up-regulation or GABRA1 silencing abolished these trends.
Conclusively, Gm37494 elevated GABRA1 expression by binding to miR-181a-5p, thus ameliorating OA-induced chondrocyte damage.
本研究旨在探讨长链非编码 RNA（lncRNA）Gm37494 对骨关节炎（OA）的影响及其相关分子机制。
取 OA 患者的软骨组织，通过内侧半月板不稳定法建立 OA 小鼠模型，检测 Gm37494、微小 RNA（miR）-181a-5p、GABRA1mRNA 及其编码的 GABAR 蛋白表达。随后，用白细胞介素-1β（IL-1β）处理软骨细胞诱导细胞模型，进行异位和沉默实验。通过 CCK-8 和 EdU 检测试剂盒检测软骨细胞增殖，流式细胞术和 Western blot 检测软骨细胞凋亡，ELISA 检测炎症因子水平。通过双荧光素酶报告基因和 RNA 免疫沉淀（RIP）实验评估 Gm37494 与 miR-181a-5p 的结合，通过双荧光素酶报告基因和 RNA 下拉实验评估 GABRA1 与 miR-181a-5p 的结合。
OA 患者和小鼠的软骨组织中 GABRA1mRNA 和 GABAR 蛋白水平降低，miR-181a-5p 表达升高。此外，OA 小鼠的 Gm37494 表达水平较低。机制上，Gm37494 直接与 miR-181a-5p 结合，负调控 GABRA1，而 miR-181a-5p 负向靶向 GABRA1。在 IL-1β 诱导的软骨细胞中，Gm37494 过表达增强细胞增殖，抑制细胞凋亡和炎症，而进一步上调 miR-181a-5p 或沉默 GABRA1 则消除了这些趋势。
总之，Gm37494 通过与 miR-181a-5p 结合，上调 GABRA1 表达，从而改善 OA 诱导的软骨细胞损伤。
