Morphological Observation on Critical-Sized Cranial Defect Repaired by Icariin and Autologous Concentrate Growth Factors in Rabbits

BACKGROUND: Morphological changes repaired by icariin and autologous concentrate growth factors (ACGF) in critical-sized cranial defect were observed and their promoting effects were investigated. MATERIAL/METHODS: Seventy-two New Zealand white rabbits weighing 1.8~2.0kg were used to build a critical-sized cranial defect model and were randomly divided into 3 groups. X-ray, HE staining, general and histological observation, and immunohistochemistry were used to describe the changes caused by normal saline, icariin, and ACGF. RESULTS: Cranial defects were covered with newly formed bone tissue at the 12(th) week in icariin and ACGF groups, with red color, hard surface, and no obvious boundary. Densities were the same in 2 groups at 4 timepoints. HE staining showed defects filled with a large amount of fibrous connective tissue, thick collagen fibers, and abundant osteoclasts. No new bone matrix appeared in any of the 3 groups. Trabecular area, trabeculae width, and osteoblast number in 2 groups were more than that of the control group, and osteoclast number was lower. However, osteoclast number among the 3 groups at the 12(th) week had no significant difference, which was the same with 4 indicators between the icariin and ACGF groups. From the 4(th) to 12(th) week, regenerated cartilage was formed and showed positive reaction with BMP-2 and TGFβ1 from primary bone, which also was demonstrated by granulation tissue and uniform dyeing. CONCLUSIONS: ACGF and icariin both can increase new bone quantity and improve bone quality, which can also promote healing. The effects and mechanisms of icariin and ACGF on the expression of gene are not exactly the same.