CR6-interacting factor-1 contributes to osteoclastogenesis by inducing receptor activator of nuclear factor κB ligand after radiation

Figure 1 Radiation induces bone loss and increased CR6-interacting factor-1 expression in mice. A: Micro-computed tomography images of the distal metaphysis of the femur. Mice (n = 6/group ) were exposed to Co-60 gamma rays, and received 5 Gy of whole-body sublethal irradiation at a rate of 0.69 Gy/min; B-H: Micro-computed tomography analysis of the trabecular bone volume/total volume (B), connectivity density (C), trabecular number (D), bone mineral density (E), trabecular thickness (F), trabecular spacing (G), and structure model index (H); I: Hematoxylin-eosin staining of femoral sections from irradiated mice and controls. Femoral sections from irradiated mice showed significantly decreased trabecular bone compared to controls; J: Hematoxylin-eosin staining of femoral sections from irradiated mice and controls. Femoral sections from irradiated mice showed that adipocytes increased significantly in irradiated mice; K: Tartrate-resistant acid phosphatase staining of femoral sections from irradiated mice and controls; L: Real-time quantitative polymerase chain reaction (RT-qPCR) analysis of receptor activator of nuclear factor κB ligand and osteoprotegerin mRNA expression in flushed whole bone marrow; M: Receptor activator of nuclear factor κB ligand/osteoprotegerin ratio based on RT-qPCR results; N: RT-qPCR analysis of CR6-interacting factor-1 mRNA expression in flushed whole bone marrow; O: Western blot analysis of CR6-interacting factor-1 expression in flushed whole bone marrow. ^aP < 0.05, ^bP < 0.01, and the bars represent the mean ± SD. OPG: Osteoprotegerin; RANKL: Receptor activator of nuclear factor κB ligand; Crif1: CR6-interacting factor-1; BM: Bone marrow; SMI: Structure model index; BV/TV: Bone volume/total volume; Conn.D: Connectivity density; Tb.N: Trabecular number; vBMD: Bone mineral density; Tb.Sp: Trabecular spacing; Tb.Th: Trabecular thickness.