Lentivirus‑mediated transfer of gene encoding fibroblast growth factor‑18 inhibits intervertebral disc degeneration

Abstract

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. In vitro, 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 in vivo. 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.

Adeno-Associated Virus-Delivered Fibroblast Growth Factor 18 Gene Therapy Promotes Cartilage Anabolism

“…The synovitis we observed with rhFGF18 treatment was therefore attributed to the consistent disruption of the joint capsule due to repeated injections, which likely drove the pathology. These findings are in line with the previously published studies of viral vector–delivered rhFGF18 in the pinna and intravertebral disk, 41 , 60 which also did not report any treatment-related side effects.…”

Role of signaling pathways in age-related orthopedic diseases: focus on the fibroblast growth factor family

“…Additionally, FGF18 can inhibit the apoptosis of NP cells, thereby providing further protection for the IVD. FGF18 increases the expression of Col-2 and CA12 in NP cells while decreasing degeneration in vertebral joint NP [ 11 , 144 ]. Currently, research related to FGF18 primarily focuses on cartilage and NPs rather than other tissues like AF.…”

“…For example, FGF1 and FGF8 may contribute to cartilage destruction during the development of OA [ 9 , 10 ], whereas FGF18 can promote cartilage repair and protect joint cartilage integrity. Additionally, FGF18 inhibits apoptosis of nucleus pulposus (NP) cells protecting intervertebral discs (IVDs) affected by IVDD [ 11 ]. In cases of sarcopenia and OP, FGF shows potential for slowing down or reversing disease progression.…”

Application of single and cooperative different delivery systems for the treatment of intervertebral disc degeneration

“…Wu et al ( Wu et al, 2014 ) reported that lentiviral vector-mediated gene expression lasted nearly twice as long as AAV in human NP cells. The regulation of IDD-related factors such as inflammation, ECM and apoptosis by lentiviral vectors has been reported ( Farhang et al, 2019 ; Lin et al, 2021 ; Lu et al, 2021 ; Lu and Lin, 2021 ).…”