Ying Hongliang, Li Qiang, Zhao Changfu
Department of Orthopaedic Surgery, China-Japan Unite Hospital of Jilin University Changchun 130033, China.
Am J Transl Res. 2016 May 15;8(5):2411-8. eCollection 2016.
Bone trauma healing is a complex physiological process, which may involve the function of various inflammatory cytokines. Our study aimed to explore the roles of inflammatory cytokines in bone trauma healing and reveal the potential mechanism. Concentrations of interleukin (IL)-6, IL-1β and tumor necrosis factor alpha (TNF-α) in peripheral blood serum of bone trauma patients after surgery were determined by ELISA. The human osteoblast hFOB1.19 cell line was cultured to determine the effect of these cytokines in cell viability using MTT assay. In addition, luciferase reporter assay was performed to investigate the activator protein 1 (AP1) transcriptional activity, and small interfering RNA was transfected to inhibit FOS, a component of AP1 molecule. IL-6, IL-1β and TNF-α exhibited higher level in patients with more severe bone traumas after surgery. IL-1β and TNF-α, but not IL-6, induced a significant increase of hFOB1.19 viability after three days of treatment (P < 0.05). IL-1β and TNF-α could activate AP1 transcriptional activity in hFOB1.19 cells (P < 0.001), but the activation was inhibited when cells were pretreated with inhibitor of JNKs, SP600125 (P < 0.001). Besides, the effect of IL-1β and TNF-α on promoting viability was significantly inhibited after knockdown of FOS. These findings indicated that IL-1β and TNF-α played an important role in promoting osteoblast viability via the activation of AP1 transcriptional activity, which was likely to involve the JNK/MAPK signaling pathway. Modulating inflammatory cytokines is a potential strategy for improving the outcome of bone trauma healing.
骨创伤愈合是一个复杂的生理过程，可能涉及多种炎性细胞因子的作用。我们的研究旨在探讨炎性细胞因子在骨创伤愈合中的作用，并揭示其潜在机制。采用酶联免疫吸附测定法（ELISA）测定骨创伤患者术后外周血血清中白细胞介素（IL）-6、IL-1β和肿瘤坏死因子α（TNF-α）的浓度。培养人成骨细胞hFOB1.19细胞系，采用MTT法测定这些细胞因子对细胞活力的影响。此外，进行荧光素酶报告基因测定以研究激活蛋白1（AP1）的转录活性，并转染小干扰RNA以抑制AP1分子的一个组分FOS。IL-6、IL-1β和TNF-α在术后骨创伤较严重的患者中表现出更高的水平。治疗三天后，IL-1β和TNF-α而非IL-6可诱导hFOB1.19细胞活力显著增加（P < 0.05）。IL-1β和TNF-α可激活hFOB1.19细胞中的AP1转录活性（P < 0.001），但当细胞用JNKs抑制剂SP600125预处理时，这种激活作用受到抑制（P < 0.001）。此外，敲低FOS后，IL-1β和TNF-α对促进细胞活力的作用被显著抑制。这些发现表明，IL-1β和TNF-α通过激活AP1转录活性在促进成骨细胞活力方面发挥重要作用，这可能涉及JNK/丝裂原活化蛋白激酶（MAPK）信号通路。调节炎性细胞因子是改善骨创伤愈合结果的一种潜在策略。
