ABSTRACT
INTRODUCTION: The experiment was undertaken to estimate the effect of BMSC seeding in different scaffold incorporation with HBO on the repair of a seawater-immersed bone defect. And future compared n-HA/PLGA with ß-TCP/PLGA as a scaffold in treatment effect of the seawater-immersed bone defect. METHODS: Sixty New Zealand White rabbits with standard seawater defect in radius were randomly divided into group A (implant with nothing), group B (implanted with autogenous bone), group C (implanted with n-HA/PLGA/BMSCs), and group D (implanted with ß-TCP/PLGA/BMSCs). After the implant, each rabbit receives HBO treatment at 2.4 ATA 100% oxygen for 120 min/day for 2 weeks. Radiograph, histological, and biomechanical examinations were used to analyze osteogenesis. RESULT: X-ray analysis shows that n-HA/PLGA/BMSCs and ß-TCP/PLGA/BMSCs could accelerate the new bone formation, and the new bone formation in group C was larger than that in group D or group A and close to group B (P < 0.05). After 12 weeks, in group A, the defect without scaffold shows a loose connect tissue filled in the areas. The medullary canal in group B was recanalized. Defects in groups C and D show a larger number of woven bone formation. The new woven bone formation in defect areas in group C was larger than that in group D. The mechanical examination revealed ultimate strength at 12 weeks was group D > group C > group B > group A (P < 0.05). CONCLUSION: Scaffolds of n-HA/PLGA and ß-TCP/PLGA incorporation with HBO and BMSCs were effective to treat seawater-immersed bone defect, and n-HA/PLGA was more excellent than ß-TCP/PLGA.
Subject(s)
Bone Diseases/etiology , Bone Diseases/therapy , Bone Marrow Cells , Bone Marrow Transplantation/methods , Calcium Phosphates/therapeutic use , Hyperbaric Oxygenation/methods , Immersion/adverse effects , Polylactic Acid-Polyglycolic Acid Copolymer/therapeutic use , Seawater/adverse effects , Tissue Engineering/methods , Tissue Scaffolds , Animals , Bone Diseases/diagnostic imaging , Bone Diseases/pathology , Cells, Cultured , Humans , Osteogenesis , Rabbits , RadiographyABSTRACT
OBJECTIVE: To explore the effect and mechanism of hyperbaric oxygen (HBO2) therapy of open tibial fractures in rabbits after transient seawater immersion. METHODS: Forty-eight (48) New Zealand rabbits were randomly and averagely divided into an HBO2 therapy group (Group A) and a control group (Group B). All rabbits were subjected to unilateral open tibial fractures, while immersed in artificial seawater (20-22 °C) for three hours prior to debridement and external fixation. Group A was treated with HBO2 at 2 atmospheres absolute (ATA) for 50 minutes once daily for two weeks; Group B received postoperative routine treatments only. The fracture zone in each group was compared by radiological, histological and immunohistochemical examinations. RESULTS: In Group A, bony callus and mature osteocytes without infiltration of inflammatory cells were observed in the fracture zone. Vascular endothelial growth factor (VEGF) was expressed mainly in the cytoplasm of osteoblasts, chondrocytes and osteocytes, and exhibited significant changes at different time points. The gray value of bony callus in Group A was 190.58 ± 7.52; that of Group B was 144 ± 8.11. Difference between the groups was statistically significant (P ⟨ 0.01). The content of malondialdehyde (MDA) in Group A was significantly lower than Group B (P ⟨ 0.01), and the activity of superoxide dismutase (SOD) in Group A was higher than Group B (P ⟨ 0.01) at four weeks. There were no significant differences in MDA content and SOD activity between groups at eight and 12 weeks. CONCLUSIONS: HBO2 treatment of open tibial fractures in seawater can reduce the inflammatory reaction and reperfusion injury, and promote osteocytic proliferation and fracture healing.
