Fig. 9

Overexpression of HDAC9 alleviates surgery-induced IVDD in mice. A Schematic of HDAC9 overexpression and animal working model. Surgically induced IVDD model was induced by puncturing at the L5/6 IVD with a 30-gauge needle, and adenovirus carrying Col2a1-promoter mediated overexpression of HDAC9 (HDAC9^Col2a1) and NC^Col2a1 were injected to the NP tissue during needle puncture. After 4 weeks of surgery, the mice were sacrificed. B MRI scan of the lumbar spine. C, D Coronal sections of disc compartments stained and analyzed by safranin-O/fast green. Scale bar: black, 500 μm; yellow, 200 μm. E, F Apoptotic cells in the NP compartment were detected by TUNEL staining. Scale bar, 25 μm. G, H Fluorescence staining of HDAC9 in NP compartment. Scale bar, 25 μm. I The acetylation level of RUNX3 in disc tissues. Data are represented as mean ± SD (n = 6). A p value of less than 0.05 was considered significant using one-way ANOVA and Tukey’s multiple comparison test