Li Mingjuan, Li Feng, Zhu Chongjie, Zhang Chi, Le Yushi, Li Zubing, Wan Qilong
State Key Laboratory of Oral & Maxillofacial Reconstruction and Regeneration, Key Laboratory of Oral Biomedicine Ministry of Education, Hubei Key Laboratory of Stomatology, School & Hospital of Stomatology, Wuhan University, Wuhan, China.
State Key Laboratory of Oral & Maxillofacial Reconstruction and Regeneration, Key Laboratory of Oral Biomedicine Ministry of Education, Hubei Key Laboratory of Stomatology, School & Hospital of Stomatology, Wuhan University, Wuhan, China.
J Biol Chem. 2025 Apr;301(4):108389. doi: 10.1016/j.jbc.2025.108389. Epub 2025 Mar 6.
Periodontitis is a prevalent chronic inflammatory disease characterized by alveolar bone resorption mediated by osteoclasts. Pyruvate kinase M2 (PKM2), a key enzyme in glycolysis and pyruvate metabolism, has recently been recognized for its regulatory roles beyond metabolism, including gene expression and protein kinase activity. However, its exact role in osteoclastogenesis remains unclear. This study investigates the function of PKM2 in inflammatory osteoclastogenesis and explores its potential as a therapeutic target for periodontitis. Using murine bone marrow-derived macrophages (BMMs) stimulated with lipopolysaccharides (LPS) to mimic inflammatory conditions in vitro, we analyzed PKM2 expression and glycolytic activity during osteoclastogenesis through bioinformatics, tartrate-resistant acid phosphatase (TRAP) staining, phalloidin staining, quantitative real-time PCR (RT-qPCR), and Western blotting. Glycolysis was inhibited using 2-deoxy-D-glucose (2-DG), while TEPP-46 was used to activate PKM2. In a mouse model of periodontitis, the effects of TEPP-46 on alveolar bone loss were evaluated using micro-computed tomography, immunohistochemistry, TRAP staining, and hematoxylin-eosin (HE) staining. The results demonstrated that LPS significantly enhanced osteoclastogenesis and glycolysis, increasing PKM2 expression in osteoclasts. Inhibiting glycolysis with 2-DG suppressed osteoclast formation and osteoclast-related gene expression under inflammatory conditions. TEPP-46 treatment reduced nuclear dimeric PKM2 levels, decreased phosphorylated signal transducer and activator of transcription three (p-STAT3) expression, and inhibited osteoclastogenesis and osteoclast-related gene expression. Co-immunoprecipitation confirmed an interaction between nuclear dimeric PKM2 and p-STAT3. In vivo, TEPP-46 effectively reduced alveolar bone loss by preventing PKM2 nuclear translocation and STAT3 phosphorylation. These findings reveal that PKM2 regulates inflammatory osteoclastogenesis through modulation of glycolysis and STAT3 signaling, highlighting its potential as a therapeutic target for periodontitis.
牙周炎是一种常见的慢性炎症性疾病，其特征是破骨细胞介导的牙槽骨吸收。丙酮酸激酶M2（PKM2）是糖酵解和丙酮酸代谢中的关键酶，最近因其在代谢之外的调节作用而受到认可，包括基因表达和蛋白激酶活性。然而，其在破骨细胞形成中的确切作用仍不清楚。本研究调查了PKM2在炎症性破骨细胞形成中的功能，并探索其作为牙周炎治疗靶点的潜力。利用脂多糖（LPS）刺激的小鼠骨髓来源巨噬细胞（BMM）在体外模拟炎症条件，我们通过生物信息学、抗酒石酸酸性磷酸酶（TRAP）染色、鬼笔环肽染色、定量实时PCR（RT-qPCR）和蛋白质印迹分析了破骨细胞形成过程中PKM2的表达和糖酵解活性。使用2-脱氧-D-葡萄糖（2-DG）抑制糖酵解，而使用TEPP-46激活PKM2。在牙周炎小鼠模型中，使用微型计算机断层扫描、免疫组织化学、TRAP染色和苏木精-伊红（HE）染色评估TEPP-46对牙槽骨丢失的影响。结果表明，LPS显著增强了破骨细胞形成和糖酵解，增加了破骨细胞中PKM2的表达。在炎症条件下，用2-DG抑制糖酵解可抑制破骨细胞形成和破骨细胞相关基因表达。TEPP-46处理降低了核二聚体PKM2水平，降低了磷酸化信号转导和转录激活因子3（p-STAT3）的表达，并抑制了破骨细胞形成和破骨细胞相关基因表达。免疫共沉淀证实了核二聚体PKM2与p-STAT3之间的相互作用。在体内，TEPP-46通过阻止PKM2核转位和STAT3磷酸化有效减少了牙槽骨丢失。这些发现揭示了PKM2通过调节糖酵解和STAT3信号传导来调节炎症性破骨细胞形成，突出了其作为牙周炎治疗靶点的潜力。
