The Sirt1/P53 Axis in Diabetic Intervertebral Disc Degeneration Pathogenesis and Therapeutics

Figure 7

The activation of Sirt1 ameliorates IDD in rats in vivo. The diabetic rat IDD model was established by stabbing the whole layer of the annulus fibrosus (AF) of diabetic rats, which was induced by an STZ (60 mg/kg) intraperitoneal injection, through the tail skin using needles (27 G) for 1 min. MRI of 0-, 4-, and 12-week degenerated discs was performed followed by staining with H&E and Safranin O. (a, b) T2-weighted MRI of a rat tail with a needle-punctured disc at 4 and 12 weeks postsurgery (red boxes: location of the needle-puncture disc). The Pfirrmann MRI grade scores in three groups at week 4 and week 12 postsurgery are shown (6 rats at each time point for each group). (c, d) Representative S-O and HE staining of disc samples from different experimental groups at 4 weeks and 12 weeks postsurgery is shown (original magnification ×40, scale bar: 100 μm). Three sections were randomly selected for quantification, with a representative example shown. (e) The histological grades evaluated at 4 weeks and 12 weeks postsurgery in three groups (6 rats per group) are shown. The displayed values are the of 6 rats per group. Significant differences between groups are indicated as , , and . Blue: IDD group vs. Ctrl group; red: diabetic IDD group vs. IDD group; green: diabetic IDD butein group vs. diabetic IDD group.

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