The effect of Erythropoietin on bone regeneration “an experimental study”

Background: Erythropoietin (EPO) is a hematopoietic growth factor stimulating the formation of red blood cells. EPO is notoriously known as a doping substance in high-performance sports, and in cycling in particular. In recent years, the non-hematopoietic functions of EPO, also known as pleiotropic functions which include osteogenic and angiogenic potencies have been intensively investigated.
Aim of study: The objectives of the present study were to address and investigate the efficacy of EPO in regenerating bone and facilitating bone healing by using a single local dose of 1ml EPO 4000 IU per animal to augments bony ingrowth in rabbit calvarial bony defect.
Material and methods: 12 New Zealand White rabbits received a calvarial defect. Absorbable oxidized cellulose was soaked with 1ml EPO 4000 IU (local treatment group) were implanted into the gap, the other side used as (control group). Histological analysis was performed 7, 14 and 30 days postoperatively. Vascularization was evaluated histologically.
Results: Histopathological findings of bone gap after 30 days of surgery, untreated animals showed granulation tissue which invaded numerous number of inflammatory cells mainly macrophages. Bony gap showed more fibrous tissue than fibrocartilage. In treated animals group, the periosteal cells proximal to the fracture gap developed into osteoblasts. The animals group, fracture induced gap was filled with well-organized bone trabeculae. The healed bone gap revealed numerous number of proliferative osteocytes .