Association of Syndecan 4 and Osteocalcin with Application of BMP2 and BDNF in Bone Healing of Osteoporotic Rats

Abstract

Background: Bone tissue contains multipotent stromal cells, which have the ability to differentiate into
different specialized cells. Induced stem cells have been developed with various growth factors using many
biomaterials, which are the most common strategiesin tissue engineering. Syndecan 4 and osteocalcin
expressions during healing of bone defect in osteoporotic rat, along with the application of bone morphogenic
protein 2 (BMP-2) and brain-derived neurotrophic factor (BDNF), were evaluated in this study.
Method: Ten normal rats and 10 induced osteoporotic rats were used in this study. Three mm bone defects
were created in the femur of each rat, one on the left side and another one on the right side. The left bone
defects were left to heal spontaneously without any application, while the right ones were treated with a
combination of BMP2 and BDNF. Immunohistochemical evaluation was done for positive expression of
syndecan 4 and osteocalcin in bone tissue during healing periods.
Results: Application of BMP2 and BDNF for both normal and osteoporotic rats increased the expressions
of syndecan 4 and osteocalcin. In addition, expression of Syndecan 4 was decreased with increment period,
while Osteocalcin expression showed the reverse. Statistical analysis revealed a significant difference
regarding both positive expression of Syndecan 4 and osteocalcin in the treated groups compared to their
untreated counterpart.
Conclusion: Application of BMP-2 and BDNF enhances syndecan 4 and osteocalcin expressions in bone
repair of osteoporotic rat.