Fig. 5

MiR-217 upregulation prevented IDD development. A Injections of agomiR-217, antagomiR-217, or their negative controls were performed 3, 7, 14, and 21 days after surgery. B Time-dependent fluorescence images of mice treated for 24 and 72 h with agomiR-217, antagomiR-217, or their negative controls labelled by Cy3. Blue to red indicates low to high intensity of the fluorescence signal. C X-ray examination of intervertebral disc degeneration. The DHI was tested after 12 weeks of treatment with different agents. D Histological findings 12 weeks after IDD surgery. In the negative control group, there was a decrease in the number of NP cells, which were replaced by cells with a more fibroblast-like phenotype. However, there was an increase in the number of NP cells in the group treated with agomiR-217 compared to the group treated with antagomiR-217 or negative controls. Moreover, the histology scores were evaluated. E, F MMP13 and Col II immunostaining in IDD models with different treatments. Scale bar = 20 μm. G FCM was used to evaluate apoptotic activity in the intervertebral disc; scale bar = 200 μm. IDD, intervertebral disc degeneration; NC, negative control; miR, microRNA; Col II, type II collagen; MMP, matrix metalloprotein; FCM, flow cytometry. ***P < 0.001