Effects of porcine bone protein on serum phosphorus level and bone mineral density in a rat model of osteoporosis / 中国组织工程研究

ABSTRACT

BACKGROUND: Several studies have demonstrated that many American women who are at high risk of developing osteoporosis have higher levels of serum phosphorus. This indicates that some substances which can lower the serum level of phosphorus will supply a new and effective method to prevent and treat osteoporosis.OBJECTIVE: To observe the influences of porcine bone protein on bone mineral density (BMD) and serum levels of calcium and phosphorus in a rat model of osteoporosis.METHODS: Wistar rat models of osteoporosis were established by intramuscular injection of dexamethasone. Rat models were randomly divided into physiological saline, Jiegu Qili tablet, 50, 100, 200 mg/kg porcine bone protein groups. Rats that did not receive any treatments served as normal controls. After 12 weeks of treatment, serum was collected and serum levels of phosphorus and calcium were determined by biochemistry method. At the same time, tibia sections were made to determine tibial DMD by QDR-400 dual energy X-ray absorptiometry and to observe tibia marrow cavity by hematoxylin-eosin staining.RESULTS AND CONCLUSION: There was no significant difference in serum level of calcium among groups (P＞0.05).Compared with the physiological saline group, serum level of phosphorus in the 50, 100, 200 mg/kg porcine bone protein groups was significantly decreased (P ＜ 0.05). BMD was significantly higher in the 50, 100, 200 mg/kg porcine bone protein, Jiegu Qili tablet groups than in the physiological saline group (P ＜ 0.05). The tibia marrow cavity was smallest in the normal control group and largest in the physiological saline group. The tibia marrow cavity was larger in the 50, 100, 200 mg/kg porcine bone protein,Jiegu Qili tablet groups than in the physiological saline group. These results indicate that porcine bone protein cannot change the serum level of calcium, but it lowers serum level of phosphorus, and increases BMD, in a rat model of osteoporosis. However, the dose-dependent effect of porcine bone protein was not observed within the present experimental dosage. In addition, porcine bone protein can also reduce the marrow cavity of the tibia of rats with osteoporosis.