Inhibitory effects of strontium ranelate on titanium particle-induced inflammatory osteolysis

Objective To observe the effect of strontium ranelate(SR)on titanium(Ti)particles-induced inflammatory osteolysis through restraining osteoclastogenesis in a murine osteolysis model.Methods Thirty male C57BL/J6mice,8-10weeks old,were enrolled in the study.All experimental animals were randomly divided into three groups:blank group,Ti group,SR group.SR [600mg/(kg·d)]was administrated to mice when the Ti particles were implanted and maintained until the mice were sacrificed.The calvaria were collected 10days after Ti implantation for histological and molecular analyses.HE staining was used to count the bone resorption area and the periosteum thickness of calvaria by using computerized image analysis system.Tartrate-resistant acid-phosphatase(TRAP)staining was done to determine the number of osteoclast-like cells.The levels of tumor necrosis factor-α(TNF-α),interleukin-1β(IL-1β)and IL-6 were examined by enzyme linked immunoabsorbent assay(ELISA).Results The quantitative image analysis of histological sections revealed that the bone resorption area and the periosteum thickness of calvaria were remarkably different among the three groups(P0.05).TRAP staining showed that SR could significantly decrease the number of TRAP positive cells in calvaria as compared with Ti group(P0.05).The results of ELISA suggested that SR could significantly reduce the protein level of TNF-α,IL-1βand IL-6induced by Ti particles in a murine osteolysis model.Conclusion This study provides evidence that SR can markedly inhibit Ti-particle-induced inflammatory osteolysis,and could be developed as a potential compound for the prevention and treatment of osteolysis and subsequent aseptic loosening after total joint replacement.