Lu Sheng, Lin Chao-Wei
Department of Spine Surgery, The First Affiliated Hospital of Wenzhou Medical University, Wenzhou, Zhejiang 325000, P.R. China.
Exp Ther Med. 2021 Aug;22(2):856. doi: 10.3892/etm.2021.10288. Epub 2021 Jun 9.
Fibroblast growth factor 18 (FGF-18) is a well-characterized anabolic growth factor involved in cartilage homeostasis. However, the effect of FGF-18 on intervertebral disc (IVD) degeneration has not been investigated. The present study aimed to investigate the role of FGF-18 in the process of rabbit IVD degeneration. , primary nucleus pulposus cells (NPs) were cultured and transfected with a lentivirus. Tert-butyl hydroperoxide (TBHP) was used to induce apoptosis in NPs on the second passage, while overexpression of FGF-18 in NPs attenuated TBHP-induced apoptosis. A rabbit annular puncture model was generated to induce IVD degeneration . The discs were injected with an FGF-18-overexpression lentivirus or a negative control lentivirus. In the sham group, the discs were exposed and not punctured. Disc degeneration was evaluated using H&E staining and a histological grading system. Reverse transcription-quantitative PCR was used to detect the expression of the extracellular matrix-degrading enzymes matrix metalloproteinase-3 (MMP-3) and A disintegrin and metalloproteinase with thrombospondin motifs 5 (ADAMTS-5). Nucleus pulposus apoptosis was detected via western blotting, immunohistochemical methods and TUNEL staining. Histologic examination showed that disc degeneration was attenuated after FGF-18 overexpression treatment. At 8 weeks after surgery, the expression of MMP-3 and ADAMTS-5 in the annular puncture groups was higher compared with in the sham group. FGF-18 treatment inhibited the expression of MMP-3 and ADAMTS-5 at the mRNA level. Western blot assays indicated that the expression level of Bax was significantly reduced in the FGF-18 groups, and that the expression level of Bcl-2 was significantly increased compared with those in the control group. Moreover, immunohistochemical analysis indicated that the FGF-18 group exhibited a lower percentage of cleaved caspase 3-positive NPs. Quantification of the TUNEL staining demonstrated that the FGF-18 group had fewer apoptotic NPs than the control group. These findings indicated that FGF-18 could delay IVD degeneration by inhibiting the apoptosis of NPs and the expression of matrix-degrading enzymes.
成纤维细胞生长因子18（FGF - 18）是一种已被充分表征的参与软骨稳态的合成代谢生长因子。然而，FGF - 18对椎间盘（IVD）退变的影响尚未得到研究。本研究旨在探讨FGF - 18在兔IVD退变过程中的作用。首先，培养原代髓核细胞（NPs）并用慢病毒进行转染。在第二代时，使用叔丁基过氧化氢（TBHP）诱导NPs凋亡，而NPs中FGF - 18的过表达减弱了TBHP诱导的凋亡。构建兔椎间盘穿刺模型以诱导IVD退变。向椎间盘内注射FGF - 18过表达慢病毒或阴性对照慢病毒。在假手术组中，暴露椎间盘但不进行穿刺。使用苏木精 - 伊红（H&E）染色和组织学分级系统评估椎间盘退变情况。采用逆转录定量聚合酶链反应检测细胞外基质降解酶基质金属蛋白酶 - 3（MMP - 3）和含血小板反应蛋白基序的解聚素和金属蛋白酶5（ADAMTS - 5）的表达。通过蛋白质印迹法、免疫组织化学方法和TUNEL染色检测髓核凋亡情况。组织学检查显示，FGF - 18过表达治疗后椎间盘退变减轻。术后8周，与假手术组相比，穿刺组中MMP - 3和ADAMTS - 5在mRNA水平的表达更高。FGF - 18治疗在mRNA水平抑制了MMP - 3和ADAMTS - 5的表达。蛋白质印迹分析表明，与对照组相比，FGF - 18组中Bax的表达水平显著降低，Bcl - 2的表达水平显著升高。此外，免疫组织化学分析表明，FGF - 18组中裂解的半胱天冬酶3阳性NPs的百分比更低。TUNEL染色定量显示，FGF - 18组的凋亡NPs比对照组少。这些结果表明，FGF - 18可通过抑制NPs凋亡和基质降解酶的表达来延缓IVD退变。
