Fig. 8.

NMN Administration ameliorated IVD degeneration in vivo. The rat tail discs were injected with PBS, AGEs (200 μg/ml), the mixture of AGEs (200 μg/ml) and NMN (100 μM), maintained for one month. (A) Rat tails were examined using MRI at T2-weighted signal and representative MRI images with white squares labeling the operated levels were shown. (B, C) Whole tail discs were observed using HE and SO staining. (D) TUNEL staining and fluorescence microscope analysis were used to detected apoptosis in rat tail discs. The quantitative analysis of degenerative degree using MRI images according to Pfirrmann grade system (E), HE and SO staining images according to histological grading scale (F) and TUNEL fluorescent images by positive cell ratios (G). *p < 0.05 versus PBS. #p < 0.05 versus AGEs.