Han Jiaheng, Ding Zhili, Huang Jie, Zhang Yan, Ding Yu
Department of Orthopaedics, School of Medicine, South China University of Technology, Guangzhou, 51006, China.
Orthopedics of TCM Senior Department, The Sixth Medical Center of PLA General Hospital, Beijing, 100048, China.
J Orthop Surg Res. 2025 Aug 22;20(1):786. doi: 10.1186/s13018-025-06205-0.
Intervertebral disc degeneration (IVDD) is characterized by nucleus pulposus cells (NPCs) apoptosis and extracellular matrix (ECM) degradation. Impaired autophagy and mitochondrial dysfunction further accelerate disc degeneration. Pure platelet-rich plasma (P-PRP), enriched in growth factors and low in pro-inflammatory mediators, has shown regenerative potential. However, its mechanism of action, particularly the role of the autophagy-related SIRT1 pathway and mitochondrial homeostasis, remains unclear.
Rabbit-derived P-PRP was prepared and analyzed for cellular content and cytokine profiling. NPCs were treated with whole blood or P-PRP, and assessed for viability (CCK-8) and migration (Transwell). An IL-1β-induced degeneration model was established, and groups were treated with SIRT1 activator (SRT1720), inhibitor (EX527), P-PRP, or P-PRP + EX527. Mitochondrial membrane potential (JC-1 staining), and apoptosis (Annexin V/PI flow cytometry) were also measured. Western blotting, immunofluorescence, qPCR, and ELISA were conducted to measure the expression of SIRT1, autophagy-related proteins, and ECM-related markers.
P-PRP promoted the viability and migration of NPCs, reduced apoptosis, and preserved ECM homeostasis in inflammatory conditions. P-PRP enhanced the expression of SIRT1, improved mitochondrial membrane potential, and reduced apoptosis rates. P-PRP upregulated LC3B-II and Beclin-1 expression, while downregulated p62 expression, indicating autophagy activation. EX-527 abrogated the beneficial effects of P-PRP.
P-PRP protected against degenerative NPCs by activating functional autophagic flux and restoring mitochondrial function via the SIRT1 signaling axis. These findings provide novel mechanistic insight into PRP-based therapies and identify SIRT1 as a promising target for the treatment of IVDD.
椎间盘退变（IVDD）的特征是髓核细胞（NPCs）凋亡和细胞外基质（ECM）降解。自噬受损和线粒体功能障碍会进一步加速椎间盘退变。富含生长因子且促炎介质含量低的纯富血小板血浆（P-PRP）已显示出再生潜力。然而，其作用机制，特别是自噬相关的SIRT1途径和线粒体稳态的作用仍不清楚。
制备兔源P-PRP，并分析其细胞成分和细胞因子谱。用全血或P-PRP处理NPCs，并评估其活力（CCK-8法）和迁移能力（Transwell法）。建立白细胞介素-1β诱导的退变模型，各实验组分别用SIRT1激活剂（SRT1720）、抑制剂（EX527）、P-PRP或P-PRP + EX527进行处理。还测量了线粒体膜电位（JC-1染色）和凋亡情况（Annexin V/PI流式细胞术）。进行蛋白质免疫印迹、免疫荧光、qPCR和ELISA检测，以测量SIRT1、自噬相关蛋白和ECM相关标志物的表达。
P-PRP促进了NPCs的活力和迁移，减少了凋亡，并在炎症条件下维持了ECM稳态。P-PRP增强了SIRT1的表达，改善了线粒体膜电位，并降低了凋亡率。P-PRP上调了LC3B-II和Beclin-1的表达，同时下调了p62的表达，表明自噬被激活。EX-527消除了P-PRP的有益作用。
P-PRP通过激活功能性自噬流并通过SIRT1信号轴恢复线粒体功能，从而保护退变的NPCs。这些发现为基于PRP的治疗提供了新的机制见解，并确定SIRT1是治疗IVDD的一个有前景的靶点。
