Department of Orthopaedics, Affiliated Hospital 2 of Nantong University, Nantong, Jiangsu 226001, China.
Department of Orthopaedics, Affiliated Hospital 2 of Nantong University, Nantong, Jiangsu 226001, China; Medical School of Southeast University, Nanjing, Jiangsu 210009, China.
Cytokine. 2024 Nov;183:156746. doi: 10.1016/j.cyto.2024.156746. Epub 2024 Sep 5.
Osteoarthritis (OA) is a common musculoskeletal disorder characterized by chondrocyte apoptosis and extracellular matrix degradation. This study aimed to investigate the role of CCL4/CCR5 in regulating chondrocyte apoptosis and reactive oxygen species (ROS) levels in OA progression.
Bioinformatics analysis was employed to identify CCL4 as the target gene, following which primary chondrocytes were treated with varying concentrations of CCL4. Apoptosis rate of chondrocytes and ROS levels were assessed using flow cytometry. The mechanism by which CCL4 regulated the extracellular matrix was investigated through Western blot and Immunofluorescence analyses. Additionally, maraviroc, a CCR5 inhibitor, was administered to chondrocytes in order to explore the potential signaling pathway of CCL4/CCR5.
Our study found that CCL4 was predominantly up-regulated among the top 10 hub genes identified in RNA-sequencing analysis. Validation through quantitative polymerase chain reaction (qPCR) confirmed elevated CCL4 expression in patients with Hip joint osteoarthritis, knee joint osteoarthritis, and facet joint osteoarthritis. The upregulation of CCL4 was associated with an increase in chondrocyte apoptosis and ROS levels. Mechanistically, CCL4, upon binding to its receptor CCR5, triggered the downstream phosphorylation of P65 in the nuclear factor-κB (NF-κB) signaling pathway. In vitro experiments demonstrated that treatment with maraviroc mitigated chondrocyte apoptosis, reduced intracellular ROS levels, and attenuated extracellular matrix degradation.
The study highlights the critical role of CCL4/CCR5 in modulating chondrocyte apoptosis and ROS levels in OA progression. Targeting this pathway may offer promising therapeutic interventions for mitigating the pathogenic mechanisms associated with OA.
骨关节炎（OA）是一种常见的肌肉骨骼疾病，其特征为软骨细胞凋亡和细胞外基质降解。本研究旨在探讨 CCL4/CCR5 在调节 OA 进展过程中软骨细胞凋亡和活性氧（ROS）水平中的作用。
采用生物信息学分析鉴定 CCL4 为靶基因，然后用不同浓度的 CCL4 处理原代软骨细胞。采用流式细胞术评估软骨细胞凋亡率和 ROS 水平。通过 Western blot 和免疫荧光分析研究 CCL4 调节细胞外基质的机制。此外，还向软骨细胞中给予 CCR5 抑制剂 maraviroc，以探索 CCL4/CCR5 的潜在信号通路。
本研究发现，在 RNA 测序分析中确定的前 10 个枢纽基因中，CCL4 是主要上调的基因之一。通过定量聚合酶链反应（qPCR）验证，发现在髋关节骨关节炎、膝关节骨关节炎和小关节骨关节炎患者中 CCL4 表达升高。CCL4 的上调与软骨细胞凋亡和 ROS 水平的增加有关。机制上，CCL4 与其受体 CCR5 结合后，触发核因子-κB（NF-κB）信号通路中 P65 的下游磷酸化。体外实验表明，用 maraviroc 处理可减轻软骨细胞凋亡，降低细胞内 ROS 水平，并减轻细胞外基质降解。
本研究强调了 CCL4/CCR5 在调节 OA 进展过程中软骨细胞凋亡和 ROS 水平中的关键作用。靶向该途径可能为减轻与 OA 相关的致病机制提供有前途的治疗干预措施。
