Liu Xingyu, Li Guangdi, Yang Lanqing, Pan Na, Tang Shizhong, Yu Chi, Zhang Qiang, Zeng Linghua, Goswami Ashutosh, Deng Keqi, Liao Xingzhuan, Tian You, Wu Yabin
Department of Pediatric Orthopedics, Shanghai Children's Medical Center GuiZhou Hospital, Shanghai Jiao Tong University School of Medicine, Guiyang 550081, Guizhou Province, China.
Department of Orthopedic Surgery, Affiliated Hospital of Guizhou Medical University, Guiyang 550001, Guizhou Province, China.
Int Immunopharmacol. 2025 Jul 28;163:115272. doi: 10.1016/j.intimp.2025.115272.
Circular RNAs (circRNAs) are increasingly recognized as pivotal factors in the pathogenesis of osteoarthritis (OA). CircPVT1 (ID has_circ_0001821), a circRNA family member, plays a substantial role in the progression of various human diseases; however, its specific function in OA remains to be clarified. This study aims to elucidate the expression patterns and interactions among circPVT1, miR-550a-3p, and CX3CR1 in OA, to establish a circPVT1-miR-550a-3p-CX3CR1 competitive endogenous RNA (ceRNA) network, and to evaluate its role in OA chondrocytes and its potential clinical implications.
First, a ceRNA network involving circPVT1, miR-550a-3p, and CX3CR1 was constructed using bioinformatics tools. Subsequently, direct targeting relationships between circPVT1 and miR-550a-3p, as well as between miR-550a-3p and CX3CR1, were confirmed through dual-luciferase reporter assays. Lastly, the expression patterns and interactions of circPVT1, miR-550a-3p, and CX3CR1 in OA chondrocytes, as well as their impact on chondrocyte proliferation, apoptosis, inflammatory responses, and extracellular matrix regulation, were studied using techniques such as real-time quantitative PCR, Western blot, CCK-8 cell proliferation assay, flow cytometry, and ELISA.
The results indicate that circPVT1 is abnormally upregulated in OA chondrocytes. The aberrant expression of circPVT1 impacts chondrocyte proliferation, apoptosis, inflammatory responses, and the synthesis and degradation of the extracellular matrix. Moreover, circPVT1 upregulates CX3CR1 expression by inhibiting miR-550a-3p, thereby affecting the pathological state of OA chondrocytes.
Elevated expression of circPVT1 in OA chondrocytes indicates a poor prognosis for OA patients. CircPVT1 acts as a ceRNA, competing with miR-550a-3p and weakening its inhibition of CX3CR1, thus boosting CX3CR1 levels, subsequently affecting chondrocyte growth and cell death, the release of inflammatory mediators, and both the formation and breakdown of the extracellular matrix. These findings suggest that circPVT1 could be an important biomarker and therapeutic target for OA.
环状RNA（circRNAs）日益被认为是骨关节炎（OA）发病机制中的关键因素。CircPVT1（ID为has_circ_0001821），作为circRNA家族成员，在多种人类疾病的进展中发挥重要作用；然而，其在OA中的具体功能仍有待阐明。本研究旨在阐明circPVT1、miR-550a-3p和CX3CR1在OA中的表达模式及相互作用，建立circPVT1-miR-550a-3p-CX3CR1竞争性内源RNA（ceRNA）网络，并评估其在OA软骨细胞中的作用及其潜在临床意义。
首先，利用生物信息学工具构建包含circPVT1、miR-550a-3p和CX3CR1的ceRNA网络。随后，通过双荧光素酶报告基因检测证实circPVT1与miR-550a-3p以及miR-550a-3p与CX3CR1之间的直接靶向关系。最后，运用实时定量PCR、蛋白质免疫印迹、CCK-8细胞增殖检测、流式细胞术和酶联免疫吸附测定等技术，研究circPVT1、miR-550a-3p和CX3CR1在OA软骨细胞中的表达模式及相互作用，以及它们对软骨细胞增殖、凋亡、炎症反应和细胞外基质调节的影响。
结果表明，circPVT1在OA软骨细胞中异常上调。circPVT1的异常表达影响软骨细胞的增殖、凋亡、炎症反应以及细胞外基质的合成与降解。此外，circPVT1通过抑制miR-550a-3p上调CX3CR1表达，从而影响OA软骨细胞的病理状态。
OA软骨细胞中circPVT1表达升高表明OA患者预后不良。CircPVT1作为ceRNA，与miR-550a-3p竞争并减弱其对CX3CR1的抑制作用，从而提高CX3CR1水平，进而影响软骨细胞生长和细胞死亡、炎症介质释放以及细胞外基质的形成与分解。这些发现提示circPVT1可能是OA的重要生物标志物和治疗靶点。
