Objective To investigate the changes in the expression level of PDGF in the bone callus of rats with femoral fracture and brain injury to explore the effect of brain injury on the fracture heal ing and the related mechanism. Methods Sixty-four 12-week-old SD rats weighing (356 ± 25) g were randomly divided into 8 groups with 8 rats in each. The rats in groups A1, B1, C1 and D1 had a femoral fracture and a brain injury for 1, 2, 3 and 4 weeks, respectively; the rats in groups A2, B2, C2 and D2 had a mere fracture without a brain injury for 1, 2, 3 and 4 weeks, respectively. After the CR films were taken, the bone callus was obtained 1, 2, 3 and 4 weeks after operation, respectively. Then, the bone callus and its histology were examined by HE staining, the expressions and changes in the level of PDGF were examined by the immunohistochemical staining, and the level of PDGF mRNA was measured by in situ hybridization. Results The CR films showed that the callus formation in the A1-D1 groups was earl ier and greater than that in the A2-D2 groups at the same time point. The HE staining indicated that more fibroblasts and early-stage chondrocytes were found in group A1; some fibroblasts in the fracture interspace and few early-stage chondrocytes were found in group A2; some newly-formed trabecular bones were found at the end of the fracture in group B1; but no trabecular bone formation was found in group B2; woven bone formation and a few chondrocytes between trabecular bones in the fracture interspace were found in group C1; only a few trabecular bones in the fracture interspace were found in group C2；woven bones turned to lamellar bones in group D1；and more immature trabecular bones in the fracture interspace were found in group D2. The positive expression of PDGF and PDGF mRNA was b in the cytoplasms of fibroblasts, mesenchymal cells, vascular endothel ial cells, early-stage chondrocytes, osteoblasts and osteoclasts. The percentage of the positive cells for PDGF and PDGF mRNA in the callus was significantly higher in groups A1-D1 than in groups A2-D2 at the same time point (P lt; 0.05). Conclusion Brain injury can promote the fracture heal ing process, which is probably related to an increase in the expression level of PDGF after the brain injury.
Objective To investigate the effects of xianl inggubao (XLGB) on subchondral bone and articular cartilage in the rat osteoarthritis model induced by anterior cruciate l igament transection (ACLT). Methods Twentyfour 3-month-old female SD rats were divided randomly into 3 groups (n=8): Sham group (group A), ACLT group (group B) and XLGB group (group C). The osteoarthritis model was made by ACLT in groups B and C, the joint cave was sutured after exposure of ACL in group A. After 4 days, XLGB was given at 250 mg/(kg·d) in group C and the equivalent amount of sal ine was given in groups A and B. After 12 weeks, the gross appearance of femoral condyles was observed, the degree of cartilagedegeneration was scored by Mankin scoring system. The immunostaining for MMP-13 was performed to investigate the effect of XLGB on prevention of cartilage matrix loss. The bone mineral density (BMD) measurement and bone histomorphometric analysis were done in subchondral bone of right distal femur and proximal tibia after 12 weeks. Results The gross appearance of femoral condyles showed that ulcer in the group C was smaller than that in group B after 12 weeks. The Mankin’s scale and IA value for MMP-13 in group C were markedly lower than those in group B (P lt; 0.05). BMD of the subchondral bone in the group B was significantly lower than those in the groups A and C (P lt; 0.05). The bone mass in group C were significantly higher than that in group B (P lt; 0.05). Conclusion Oral administration of XLGB (250 mg/ kg per day) for 12 weeks could prevent the cartilage degeneration of rats after ACLT, down-regulating MMP-13 and increasing subchondral bone mass might participate in this process.
To evaluate the effects of XiangLingGuBao (XLGB) on femoral fracture heal ing in ovariectomized (OVX) rats. Methods Forty 12-week-old female SD rats weighing (258 ± 14) g were divided randomly into 4 groups (n=10 per group): group A, sham operation by opening the abdominal cavity; group B, bilateral ovariectomy; group C, bilateral ovariectomy, transverse midshaft fracture of the right femur with intramedullary nail fixation, and normal sal ine by gavage; group D, bilateral ovariectomy, transverse midshaft fracture of the right femur with intramedullary nail fixation, and 250 mg/(kg•d) XLGB by gavage. The weight of rabbits in groups A and B was measured 0, 1, 2, 3, 4 and 5 weeks after operation. The right femur of each rat was obtained 5 weeks after operation. Total femur bone mineral density (tBMD), distal femur bone mineral density (dBMD) and middle femur bone mineral density (mBMD) were measured by double energy X-ray absorptiometry CR filming, HE staining and immunohistochemistry staining of groups C and D were performed. Results The weight of rats in group B was obviously higher than that of group A at 3, 4 and 5 weeks after operation (P lt; 0.05), indicating the animal model of postmenopausal osteoporosis was establ ished successfully. CR films showed more callus and obscure fracture l ine in group D, while less callus and distinct fracture l ine in group C. The tBMD and the dBMD of group B were far less than that of group A, the mBMD of group D was significantly higher than that of group C(P lt; 0.05), the tBMD and the dBMD of group D were higher than that of group C, but no significant difference was evidentbetween two groups (P gt; 0.05). Histology observation showed, when compared with group C, most fracture ends in groupD reached bone union, and the introduction of capillaries was evident in the marrow cavity. Immunohistochemistry staining demonstrated that the BMP-2 integrated absorbance (IA) value in groups C and D was 2.236 6 ± 0.181 8 and 3.727 3 ± 0.874 2, respectively, the VEGF IA value in groups C and D was 2.835 5 ± 0.537 0 and 3.839 6 ± 0.223 0, respectively, indicating there were significant differences between two groups (P lt; 0.05). Conclusion XLGB can obviously promote the femoral fracture heal ing in OVX rats, and speed the transformation of woven bone into lamellar bone, which may rely on its role of enhancing expression of BMP-2 and VEGF.