Department of Orthopedics, Affiliated Hospital of Youjiang Medical University for Nationalities, Youjiang Medical University for Nationalities, Guangxi Key Laboratory of basic and translational research of Bone and Joint Degenerative Diseases, Guangxi Biomedical Materials Engineering Research Center for Bone and Joint Degenerative Diseass, Guangxi Health Commission Key Laboratory of Clinical Medicine Research on Bone and Joint Degenerative Diseases Cohort, Guangxi Health Commission Key Laboratory of Biomedical Materials Research, Baise, 533000, Guangxi, China.
Youjiang Medical University for Nationalities, Baise, Guangxi, 533000, China.
Int Immunopharmacol. 2023 Nov;124(Pt B):110948. doi: 10.1016/j.intimp.2023.110948. Epub 2023 Sep 27.
We aimed to explore the effect and mechanism of the Src inhibitor PP2 on osteoarthritis (OA) progression.
The protein expressions of Src, p-Src (y418) and p-FAK in normal and OA human chondrocytes were detected by immunofluorescence (IF) analysis. Chondrocytes from the femur and tibial plateau of 3-day-old mice were extracted and inoculated into 6-well plates. The chondrocytes were co-cultured with IL-1β and different doses of PP2, and then the degeneration of extracellular matrix was analyzed. A mouse OA model was induced by destabilizing medial meniscectomy of the right knee. Two weeks after the operation, different doses of PP2 were injected intraperitoneally. The drug was given three times a week for 6 weeks, and then the mice were sacrificed. Histopathological, IF and immunoblotting analyses were used to detect key OA catabolic markers and protein expression and related signaling.
The levels of Src, p-Src (y418) and p-FAK in the knee cartilage tissue of patients with OA were abnormally increased. After chondrocytes were co-treated with IL-1β and different doses of PP2, the results showed that PP2 reduced the abnormal increase of β-catenin, p-β-catenin and other proteins induced by IL-1β, and reversed the decrease of p-Smad3, aggrecan and collagen Ⅱ protein levels. Meanwhile, intraperitoneal injection of PP2 in vivo significantly reduced the degeneration of articular cartilage in the OA mouse model.
Our data indicate that targeting Src with PP2 protected against cartilage destruction in an OA mouse model by inhibiting Wnt/β-catenin and activating TGF-β/Smad signaling, suggesting that Src may be a potential therapeutic target for OA treatment.
探讨Src 抑制剂 PP2 对骨关节炎（OA）进展的作用及机制。
采用免疫荧光（IF）分析检测正常和 OA 人软骨细胞中 Src、p-Src（y418）和 p-FAK 的蛋白表达。提取 3 日龄小鼠股骨和胫骨平台的软骨细胞，接种于 6 孔板中。将软骨细胞与 IL-1β和不同浓度的 PP2 共培养，然后分析细胞外基质的退变情况。采用右膝内侧半月板切除术不稳定法建立小鼠 OA 模型。术后 2 周，经腹腔注射不同浓度的 PP2。每周给药 3 次，共 6 周，然后处死小鼠。采用组织病理学、IF 和免疫印迹分析检测关键 OA 分解代谢标志物和蛋白表达及相关信号。
OA 患者膝关节软骨组织中 Src、p-Src（y418）和 p-FAK 水平异常升高。软骨细胞与 IL-1β和不同浓度的 PP2 共处理后，结果表明 PP2 降低了 IL-1β诱导的β-连环蛋白、p-β-连环蛋白等蛋白的异常增加，并逆转了 p-Smad3、聚集蛋白和胶原Ⅱ蛋白水平的降低。同时，体内腹腔注射 PP2 明显减轻了 OA 小鼠模型中关节软骨的退变。
我们的数据表明，PP2 通过抑制 Wnt/β-连环蛋白和激活 TGF-β/Smad 信号通路，靶向 Src 可防止 OA 小鼠模型中的软骨破坏，提示 Src 可能是 OA 治疗的潜在治疗靶点。
