Fig. 5

Hypoxia signaling pathway stimulation does not cause major changes in cortical bone mass, porosity, and bone matrix composition. a Transversal µCT views of the mid-diaphysis of tibias from mice on ND or HFD and treated with FG-4592 or vehicle. b Cortical bone µCT analysis, showing cortical thickness (C.Th), medullary area (M.Ar), periosteal bone perimeter (B.Pm), and endocortical bone perimeter (Ec.Pm) measured 2.5 mm below the growth plate. c Illustration of the cortical porosity segmentation pipeline. µCT scans at 5 µm voxel size were segmented into mineralized and non-mineralized cortex; non-mineralized intracortical space was then segmented into lacunar porosity (<8 µm Ø) and intracortical channels (>8 µm Ø). d Representative images of cortical porosity of vehicle-injected animals on ND versus HFD, showing lacunar porosity in green and intracortical channels in pink. e Quantification of total cortical porosity, lacunar porosity, and intracortical channels (all in volume % relative to cortical volume), and of the intracortical channels’ connectivity, depicting network complexity. f FTIRM analysis outline, showing a representative tibia MMA section depicting the localization of the different ROIs in the proximal (ROI 4–7) and distal/diaphyseal (ROI 1–3, 8–10) regions of the cortex (red squares, 50 × 50 µm each). g-h FTIRM results, showing collagen maturity in the proximal cortex (g), and mineral to matrix ratio in the diaphyseal cortex (h). For details, see Fig. S3. i Western blot for AGEs in femur protein extracts, with histone H3 as loading control (n = 2/group). Statistical analyses were done by two-way ANOVA, with multiple comparisons between diets and treatments; n = 7–9 mice/group; *P < 0.05; **P < 0.01; ***P < 0.00 1; ****P < 0.000 1; ns, not significant. Interaction between the diet and treatment was statistically significant for the data shown in (b) (except for Ct.Th.) and (g)