Urolithin a alleviates oxidative stress-induced senescence in nucleus pulposus-derived mesenchymal stem cells through SIRT1/PGC-1α pathway

Figure 8 Hematoxylin-eosin, Safranin-O and Toluidine blue staining. A: Hematoxylin-eosin staining at 4 wk after puncture in different groups; B: Quantitative analysis of histological score in different groups (scale bar = 1 mm); C: The expression of aggrecan and collagen type II in different groups (scale bar = 200 μm); D-E: Quantitative analysis of aggrecan and collagen type II in different groups. All data are expressed as the mean ± SD. ^aP < 0.05, ^bP < 0.01 compared with control group; ^cP < 0.05, ^dP < 0.01 compared with H₂O₂ group; ^eP < 0.05, ^fP < 0.01 compared with UA group. HE: Hematoxylin-eosin; NP: Nucleus pulposus; AF: Annulus fibrosus; IDD: Intervertebral disc degeneration; UA: Urolithin A.