Zhu Jinjian, Liu Liangliang, Lin Rengui, Guo Xiongtian, Yin Jianbin, Xie Haoyu, Lu Yuheng, Zhang Zhicheng, Zhang Hongbo, Yao Zihao, Zhang Haiyan, Wang Xiangjiang, Zeng Chun, Cai Daozhang
Department of Orthopedics, Orthopedic Hospital of Guangdong Province, Academy of Orthopedics·Guangdong Province, Guangdong Provincial Key Laboratory of Bone and Joint Degenerative Disease, The Third Affiliated Hospital of Southern Medical University, Guangzhou, 510280, China.
The Third School of Clinical Medicine, Southern Medical University, Guangzhou, China.
J Orthop Translat. 2024 Apr 1;45:226-235. doi: 10.1016/j.jot.2024.01.003. eCollection 2024 Mar.
To investigate the potential role of Ribosomal protein L35 (RPL35) in regulating chondrocyte catabolic metabolism and to examine whether osteoarthritis (OA) progression can be delayed by overexpressing RPL35 in a mouse compression loading model.
RNA sequencing analysis was performed on chondrocytes treated with or without 20 % elongation strain loading for 24 h. Experimental OA in mice was induced by destabilization of the medial meniscus and compression loading. Mice were randomly assigned to a sham group, an intra-articular adenovirus-mediated overexpression of the negative group, and an intra-articular adenovirus-mediated overexpression of the RPL35 operated group. The Osteoarthritis Research Society International score was used to evaluate cartilage degeneration. Immunostaining and western blot analyses were conducted to detect relative protein levels. Primary mouse chondrocytes were treated with 20 % elongation strain loading for 24 h to investigate the role of RPL35 in modulating chondrocyte catabolic metabolism and regulating cellular senescence in chondrocytes.
The protein expression of RPL35 in mouse chondrocytes was significantly reduced when excessive mechanical loading was applied, while elevated protein levels of RPL35 protected articular chondrocytes from degeneration. In addition, the RPL35 knockdown alone induced chondrocyte senescence, decreased the expression of anabolic markers, and increased the expression of catabolic markers in part through the hedgehog (Hh) pathway.
These findings demonstrated a functional pathway important for OA development and identified intra-articular injection of RPL35 as a potential therapy for OA prevention and treatment.
It is necessary to develop new targeted drugs for OA due to the limitations of conventional pharmacotherapy. Our study explores and demonstrates the protective effect of RPL35 against excessive mechanical stress in OA models in vivo and in vitro in animals. These findings might provide novel insights into OA pathogenesis and show its translational potential for OA therapy.
研究核糖体蛋白L35（RPL35）在调节软骨细胞分解代谢中的潜在作用，并在小鼠压缩负荷模型中检测过表达RPL35是否能延缓骨关节炎（OA）进展。
对施加或未施加20%伸长应变负荷24小时的软骨细胞进行RNA测序分析。通过内侧半月板不稳定和压缩负荷诱导小鼠实验性OA。将小鼠随机分为假手术组、关节内腺病毒介导的阴性过表达组和关节内腺病毒介导的RPL35过表达手术组。采用国际骨关节炎研究学会评分评估软骨退变情况。进行免疫染色和蛋白质印迹分析以检测相关蛋白水平。对原代小鼠软骨细胞施加20%伸长应变负荷24小时，以研究RPL35在调节软骨细胞分解代谢和调控软骨细胞衰老中的作用。
施加过度机械负荷时，小鼠软骨细胞中RPL35的蛋白表达显著降低，而RPL35蛋白水平升高可保护关节软骨细胞免于退变。此外，单独敲低RPL35可诱导软骨细胞衰老，降低合成代谢标志物的表达，并部分通过刺猬（Hh）通路增加分解代谢标志物的表达。
这些发现证明了一条对OA发展重要的功能通路，并确定关节内注射RPL35作为OA预防和治疗的潜在疗法。
由于传统药物治疗的局限性，有必要开发新的OA靶向药物。我们的研究探索并证明了RPL35在体内和体外动物OA模型中对过度机械应力的保护作用。这些发现可能为OA发病机制提供新的见解，并显示其在OA治疗中的转化潜力。
