Fig. 6: Age-related joint degeneration.

a Cohorts (n = 6) of young adult (4 months) and aged (12 months) wild-type (WT) mice were analyzed by iodine contrast-enhanced μCT (ICEμCT), joint surface replication (JSR) and subchondral X-ray microradiography (scXRM). b ICEμCT images of lateral tibial plateau articular cartilage (red) and subchondral bone (blue). Graphs show median articular cartilage thickness (Median Cg.Th) and subchondral bone BV/TV (SC BV/TV). c Back-scattered electron-scanning electron microscopy images of lateral tibial plateau JSRs. Graph shows articular cartilage (Cg) damage. d ScXRM images of proximal tibia and the lateral tibial plateau subchondral bone region of interest (dashed box) in which greyscale images are pseudocoloured according to a 16 color look-up table in which low bone mineral content (BMC) is yellow and high BMC is pink. Graph shows subchondral BMC (SC BMC). e Coronal sections of lateral knee joint compartment stained with Safranin-O/Fast green (n = 6 mice/group). Graph shows maximum OARSI histological scores. Arrow indicates cartilage damage. Scale bars = 100 μm (b, c, e) and 1 mm (d). *P < 0.05, **P < 0.01, two-tailed t test (SC BV/TV, P = 0.0082) or two-tailed Wilcoxon rank sum test (Cg. Damage Area, P = 0.0022 and Max. OARSI score, P = 0.0240). mm millimeter. Source data are provided as a Source Data file.