AGEs are 31% higher in aHFD (42.8 ± 7.6 ng quinine/mg Selleck ��-Nicotinamide collagen) vs. aLFD (56.1 ± 9.2 ng/mg, p < 0.001) and 6% higher in yHFD vs. yLFD (41.3 ± 5.5 ng/mg vs. 39.1 ± 8.7 ng/mg, respectively, p > 0.05). Mechanical S3I-201 testing: mechanical properties compromised with diabetic obesity

Overall, mechanical properties of cortical bone are compromised by diabetic obesity in both young and adult groups, as summarized in Fig. 4. Compared to the control groups, the yield strength of the bone was unchanged in aHFD (9% less, not significant), but was 17% less in yHFD (p < 0.01); corresponding maximum strengths were 15% less in aHFD (p < 0.05) and 26% less in yHFD (p < 0.01). The bending modulus was 18% less in aHFD and 32% less in yHFD (p < 0.01); fracture toughness, K c , values were 21% less in aHFD (p < 0.05), but unchanged in yHFD (8% higher, not significant). Finally, the maximum loads sustained by the bone were 22% less in aHFD (p < 0.01) and 12.5% less in yHFD (p < 0.05). These results indicate a profound reduction in mechanical quality and performance of the bone with diabetic obesity. Fig. 4 Cortical bone quality: whole-bone and tissue-level mechanical property measurements. a Young and f adult bending modulus; b young and g adult maximum load; c young and h adult yield stress; d young

and i adult max stress; e young and j adult fracture toughness. Measured size-independent mechanical properties were significantly decreased for HFD group vs. LFD Selleck JQ1 groups ROS1 (modulus, yield and maximum stress, and fracture toughness); these parameters are an indication of bone tissue quality. Size-dependent measures which address whole-bone behavior (specifically, load) also declined for HFD at both ages, likely due in part to modest bone size changes, as bone size was not able to compensate for poor

mechanical quality. yLFD n = 15, yHFD n = 15, aLFD n = 13, aHFD n = 14 (* p < 0.05; ** p < 0.01) Structural characterization: poor mineral organization and lamellar alignment of cortical bone in diabetic obese mice SEM was performed on cross-sections of femora near the fracture surface to evaluate lamellar-level structural changes. Changes in structure were most apparent at the posterior site (Fig. 5). In both the young and adult groups, the HFD bone showed marked areas of lamellar disorganization, whereas a similar area in the LFD mice appeared well-ordered. Fig. 5 SEM images of the fracture region showing cortical bone tissue structure changes at the posterior region. a yLFD group; b yHFD; c aLFD; d aHFD. The scale bar indicates 20 μm. The posterior cortex in HFD bone in (b) and (d) shows reduced alignment of osteocyte lacunae and reduction in lamellar alignment at the tissue level. These images are representative of three samples each of aHFD, yHFD, aLFD, and yLFD.