The present study investigated the detrimental effects of non-lethal, high-dose (whole body) γ-irradiation on bone, and the impact that radiation combined with skin trauma (i.e. combined injury) has on long-term skeletal tissue health. Recovery of bone after an acute dose of radiation (RI; 8. Gy), skin wounding (15-20% of total body skin surface), or combined injury (RI. +. Wound; CI) was determined 3, 7, 30, and 120. days post-irradiation in female B6D2F1 mice and compared to non-irradiated mice (SHAM) at each time-point. CI mice demonstrated long-term (day 120) elevations in serum TRAP 5b (osteoclast number) and sclerostin (bone formation inhibitor), and suppression of osteocalcin levels through 30. days as compared to SHAM (p. <. 0.05). Radiation-induced reductions in distal femur trabecular bone volume fraction and trabecular number through 120. days post-exposure were significantly greater than non-irradiated mice (p. <. 0.05) and were exacerbated in CI mice by day 30 (p. <. 0.05). Negative alterations in trabecular bone microarchitecture were coupled with extended reductions in cancellous bone formation rate in both RI and CI mice as compared to Sham (p. <. 0.05). Increased osteoclast surface in CI animals was observed for 3. days after irradiation and remained elevated through 120. days (p. <. 0.01). These results demonstrate a long-term, exacerbated response of bone to radiation when coupled with non-lethal wound trauma. Changes in cancellous bone after combined trauma were derived from extended reductions in osteoblast-driven bone formation and increases in osteoclast activity.
- Bone biomarkers
- Bone marrow
- Combined trauma
ASJC Scopus subject areas
- Endocrinology, Diabetes and Metabolism