Conclusions
miR-640 plays an important role in the degeneration of intervertebral disc and the relative inflammatory microenvironment. It is a promising potential therapeutic target for the low back pain biotherapy.
Methods
We collected 15 degenerative intervertebral tissues and five healthy donors. Nucleus pulposus and annulus fibrosus cells were subcultured. miR-640 expression was determined by qPCR. Computer analysis and luciferase reporter assay were used to confirm miR-640 target genes. Immunohistochemical and immunocytochemical staining was used to trace the proinflammatory cytokines and key transductor of signalling pathways. We also used β-galactosidase staining, flow cytometry, and cell viability assay to monitor the degenerative index.
Results
miR-640 overexpressed in patients derived degenerative nucleus pulposus tissues and cells. The inflammatory environment promoted miR-640 expression via NF-κB signalling pathway. In addition, miR-640 targeted to LRP1 and enhances NF-κB signal activity, which built a positive feedback loop. miR-640 inhibited the expression of β-catenin and EP300, therefore, restrained WNT signal and induced the degeneration in nucleus pulposus cells. miR-640 inhibitor treatment exhibited the effects of anti-inflammation, reverse WNT signalling pathway exhaustion, and remission of degenerative characteristics in vitro. Conclusions: miR-640 plays an important role in the degeneration of intervertebral disc and the relative inflammatory microenvironment. It is a promising potential therapeutic target for the low back pain biotherapy.