Liu Jiuxiang, Cheng Jiangqi, Zhou Hao, Zuo Qiang, Liu Feng
Department of Orthopedics, The First Affiliated Hospital of Nanjing Medical University (Jiangsu Province Hospital), No. 300 Guangzhou Road, NanjingJiangsu Province, 210029, China.
J Orthop Surg Res. 2024 Dec 19;19(1):860. doi: 10.1186/s13018-024-05182-0.
The long non-coding RNA CRNDE (CRNDE) has been identified as a lncRNA associated with osteoarthritis (OA), playing a role the age-related degeneration of articular cartilage. However, the precise mechanism by which CRNDE affects the physiological functions of OA chondrocytes remains unclear.
To simulate the inflammatory conditions observed in OA, interleukin (IL)-1β-stimulated chondrocyte C-28/I2 cells were utilized. The expression levels of CRNDE and miR-31 were assessed using reverse transcription-polymerase chain reaction (RT-PCR). Chondrocyte viability and apoptosis were evaluated through CCK-8 assay and flow cytometry, respectively. The levels of IL-6, IL-1β and Tumor necrosis factor (TNF-α) were determined using enzyme-linked immunosorbent assay (ELISA). mRNA expression levels of MMP-13, Aggrecan and COL2A1 were detected by quantitative RT-PCR. Western blot analysis was performed to evaluate the protein levels of factors related to cartilage matrix degradation, including p-p65, p65 and p-IκBα of the NF-κB pathway.
CRNDE expression was downregulated in both OA cartilage tissues and IL-1β-stimulated chondrocytes. Overexpression of CRNDE mitigated IL-1β-stimulated chondrocytes apoptosis, inflammatory responses, and cartilage matrix degradation. Compared with healthy controls, OA tissues exhibited reduced expression of miR-31, which was negatively correlated with the expression of CRNDE. Additionally, overexpression of miR-31 partially reversed the inhibitory effects of CRNDE on apoptosis, inflammation, cartilage matrix degradation, and the inactivation of Nuclear factor (NF)-κB pathway induced by IL-1β stimulation. Moreover, silencing of CRNDE exacerbated IL-1β-induced chondrocytes damage, which was aliviated by the NF-κB pathway inhibitor, Bay 11-7082.
CRNDE alleviated IL-1β-induced injuries in OA chondrocytes by suppressing the miR-31-mediated NF-κB signaling pathway.
长链非编码RNA CRNDE已被鉴定为一种与骨关节炎（OA）相关的长链非编码RNA，在关节软骨的年龄相关性退变中发挥作用。然而，CRNDE影响OA软骨细胞生理功能的精确机制仍不清楚。
为模拟OA中观察到的炎症状态，使用白细胞介素（IL）-1β刺激软骨细胞C-28/I2细胞。采用逆转录-聚合酶链反应（RT-PCR）评估CRNDE和miR-31的表达水平。分别通过CCK-8测定和流式细胞术评估软骨细胞活力和凋亡。使用酶联免疫吸附测定（ELISA）测定IL-6、IL-1β和肿瘤坏死因子（TNF-α）的水平。通过定量RT-PCR检测MMP-13、聚集蛋白聚糖和COL2A1的mRNA表达水平。进行蛋白质印迹分析以评估与软骨基质降解相关因子的蛋白质水平，包括NF-κB途径的p-p65、p65和p-IκBα。
CRNDE表达在OA软骨组织和IL-1β刺激的软骨细胞中均下调。CRNDE的过表达减轻了IL-1β刺激的软骨细胞凋亡、炎症反应和软骨基质降解。与健康对照相比，OA组织中miR-31表达降低，其与CRNDE的表达呈负相关。此外，miR-31的过表达部分逆转了CRNDE对IL-1β刺激诱导的凋亡、炎症、软骨基质降解和核因子（NF）-κB途径失活的抑制作用。此外，CRNDE的沉默加剧了IL-1β诱导的软骨细胞损伤，而NF-κB途径抑制剂Bay 11-7082可减轻这种损伤。
CRNDE通过抑制miR-31介导的NF-κB信号通路减轻IL-1β诱导的OA软骨细胞损伤。
