Regenerative activity of regulatory peptides in experimental bone fracture

Abstract

The aim of the study was to provide a comparative assessment of reparative osteogenesis activity and neutrophil func-tion when thymogen, dalargin, Gly-His-Lys (GHK) peptides and their paired combinations were injected into the experi-mental fracture area. Materials and methods. Peptides were administered to Wistar rats in the area of fracture for ten days from the day of injury. Equimolar single doses of the drugs were used: dalargin - 1.2 µg/kg, while thymogen and GHK were injected in a dose of 0.5 µg/kg weight. Reparative activity of osteogenesis was assessed histologically and radiologically. Phagocytic and oxygen-dependent activity of the blood neutrophils was determined. Results. All peptides and their paired combinations increased the activity of reparative osteogenesis. Even more pro-nounced bone repair activity was observed after the injection of GHK peptide in combination with dalargin or thymogen with maximum intensity in animals treated with combined administration of GHK and dalargin. The fracture of the femur bone in experimental rats was also accompanied by a decrease in phagocytic and oxygen-dependent activity of neutrophils. The peptides increased the indices of neutrophils activity more markedly when using paired combinations of peptides and with the manifestation of a corrective effect in animals receiving combined administrations of GHK and dalargin. Conclusion. Synergistic action of Gly-His-Lys peptides, thymogen and dalargin significantly enhances reparative and stimulating neutrophil function in tubular bone fractures and can be used to activate reparative osteogenesis and neutrophil bactericidal activity.