Fig 1.
Effect of HLS and radiation on trabecular parameters measured with MicroCT scans at distal femur.
Measures are shown as absolute values at conclusion of study for trabecular bone volume fraction (Tb.BVTV), trabecular thickness (Tb.Th), trabecular separation (Tb.Sp), trabecular number (Tb.N), trabecular connectivity density (Conn.Dens) and trabecular tissue mineral density (Tb.TMD). Values are means ± SEM; n = 14–18 bones/group. Values with line and asterisk indications are significantly different (p<0.05).
Fig 2.
Representative images of trabecular samples from GC mice (top) and HLS mice (bottom) on day 14.
Images represent a 72 slice region (756 μm) of distal femur.
Fig 3.
Effect of HLS and radiation on cortical parameters measured with MicroCT scans at distal femur.
Measures are shown as absolute values at conclusion of study for cortical total volume, cortical bone volume, cortical bone volume fraction (Ct. BVTV), cortical thickness, cortical bone mineral density, and cortical porosity. Values are means ± SEM; n = 14–18 bones/group. Values with line and asterisk indications are significantly different (p<0.05).
Fig 4.
Effect of HLS and radiation on mechanical properties of femurs observed during 3 point bending until failure.
Measures are shown as absolute values at conclusion of study for max force during testing (A), bone stiffness (B), and energy absorbed during testing (C). Values are means ± SEM; n = 14–18 bones/group. Values with line and asterisk indications are significantly different (p<0.05).
Fig 5.
Effect of HLS and radiation on wet muscle weight of gastrocnemius (A), quadriceps (B), and protein synthesis (C) measured with the SUnSET method. Representative Western blot of Puromycin incorporation into muscle protein for each of the six experimental groups (D left), and representative Ponceau stain demonstrating equal protein loading per lane (D right). Measures are absolute values normalized to body weight at conclusion of study (GC in protein synthesis). Values are means ± SEM; n = 14-18/group (p<0.05).
Fig 6.
Effect of HLS and radiation on phosphorylation of mTOR downstream regulators 4EBP1 and S6K1 measured via Western blot analysis.
Top panel (A) is a representative Western blot for phosphorylated and total S6K1 (B) and 4E-BP1 (C) in muscle from each of the six experimental groups; tubulin is also included to demonstrate equal protein loading all groups. All samples were run on the same gel. Bar graphs represent average values at conclusion of study and are normalized to GC group. Values are means ± SEM; n = 14-18/group, (p<0.05).
Fig 7.
Effect of HLS and radiation on 20S proteasome(A), atrogin-1 (B), MuRF-1 (C), and insulin growth factor (D) expression.
Measures are absolute values at conclusion of study. Values are means ± SEM; n = 14-18/group, Values with line and asterisk indications are significantly different (p<0.05).