DataSheet1_Nitidine Chloride Alleviates Inflammation and Cellular Senescence in Murine Osteoarthritis Through Scavenging ROS.docx

Osteoarthritis (OA) is one of the most common chronic musculoskeletal disorder worldwide, representing a major source of disability, pain and socioeconomic burden. Yet the effective pharmaceutical treatments applied in the clinical works are merely symptomatic management with uncertainty around their long-term safety and efficacy, namely no drugs currently are capable of modulating the biological progression of OA. Here, we identified the potent anti-inflammatory as well as anti-oxidative properties of Nitidine Chloride (NitC), a bioactive phytochemical alkaloid extracted from natural herbs, in IL-1β-treated rat articular chondrocytes (RACs), LPS-stimulated RAW 264.7 and rat osteoarthritic models in vivo. We demonstrated NitC remarkably inhibited the production of inflammatory mediators including COX2 and iNOS, suppressed the activation of MAPK and NF-κB cell signaling pathway and reduced the expression of extracellular matrix (ECM) degrading enzymes including MMP3, MMP9 and MMP13 in IL-1β-treated RACs. Several emerging bioinformatics tools were performed to predict the underlying mechanism, the result of which indicated the potential reactive oxygen species (ROS) clearance potential of NitC. Further, NitC exhibited its anti-oxidative potential through ameliorating cellular senescence in IL-1β-treated RACs and decreasing NLRP3 inflammasomes activation in LPS-stimulated RAW 264.7 via scavenging ROS. Additionally, X-ray, micro-CT and other experiments in vivo demonstrated that intra-articular injection of NitC significantly alleviated the cartilage erosion, ECM degradation and subchondral alterations in OA progression. In conclusion, the present study reported the potent anti-inflammatory and anti-oxidative potential of NitC in OA biological process, providing a promising therapeutic agent for OA management.

骨关节炎（Osteoarthritis, OA）是全球范围内最常见的慢性肌肉骨骼疾病之一，是致残、疼痛及社会经济负担的主要诱因。然而目前临床应用的有效药物治疗仅能实现对症管理，且其长期安全性与有效性尚存不确定性，即当前尚无药物能够调控骨关节炎的生物学进程。本研究鉴定了氯化两面针碱（Nitidine Chloride, NitC）——一种从天然草药中提取的生物活性植物化学生物碱——的强效抗炎与抗氧化特性，实验模型涵盖白细胞介素1β（IL-1β）诱导的大鼠关节软骨细胞（RACs）、脂多糖（LPS）刺激的RAW 264.7细胞以及体内大鼠骨关节炎模型。研究证实，氯化两面针碱可显著抑制白细胞介素1β处理的大鼠关节软骨细胞中炎症介质（包括环氧合酶2（COX2）与诱导型一氧化氮合酶（iNOS））的产生，抑制丝裂原活化蛋白激酶（MAPK）与核因子κB（NF-κB）细胞信号通路的激活，并降低基质金属蛋白酶3（MMP3）、基质金属蛋白酶9（MMP9）及基质金属蛋白酶13（MMP13）等细胞外基质（ECM）降解酶的表达。本研究借助多款新兴生物信息学工具预测其潜在作用机制，结果显示氯化两面针碱具备清除活性氧（ROS）的潜在能力。进一步实验表明，氯化两面针碱可通过清除活性氧，改善白细胞介素1β诱导的大鼠关节软骨细胞的细胞衰老，并抑制脂多糖刺激的RAW 264.7细胞中NLRP3炎症小体（NLRP3 inflammasomes）的激活，从而展现抗氧化潜能。此外，体内X射线、显微计算机断层扫描（micro-CT）等实验结果证实，关节腔内注射氯化两面针碱可显著缓解骨关节炎进程中的软骨侵蚀、细胞外基质降解及软骨下骨改变。综上，本研究揭示了氯化两面针碱在骨关节炎生物学进程中的强效抗炎与抗氧化潜能，为骨关节炎的临床管理提供了一种极具前景的治疗候选药物。