Reduced glutathione promotes implants osseointegration in rabbits with diabetes mellitus: An experimental study

Abstract

To observe the effects of reduced glutathione on promoting osseointegration of titanium implants in New Zealand rabbits with type I diabetes mellitus and to provide novel evidence for improving implants osseointegration. Diabetes mellitus models were established by injecting alloxan (80 mg/kg) into New Zealand rabbits. Success was verified by the blood glucose level. Titanium implants were then placed in the rabbits’ femoral epiphysis. Intravenous glutathione (GSH, 30 mg/kg) or saline, respectively, was started. The rabbits were divided into four groups: GSH-treated diabetes mellitus (GSH+DM), diabetes mellitus (DM), GSH-treated normal rabbits (GSH), normal control rabbits (NC). Four weeks after surgery, the rabbits were evaluated via general observation, micro-computed tomography (micro-CT), H&E staining and bone morphogenetic protein 2 (BMP-2) immumohistochemical staining. In results, general observation and micro-CT showed that wounds had healed, no implants had loosened, and there was good synostosis in all groups. Micro-CT also revealed that peri-implant threaded bone density was higher than that in peri-implant cancellous bone and was similar to that in femoral cortical bone. The implants tightly fused with surrounding bone tissue. HE staining revealed that large numbers of bone trabeculaes, osteoblasts, and chondrocytes in the GSH+DM group and granulation tissue, mononuclear macrophages, and multinucleated giant cells in the DM group. New bone trabecular formation was rare. There was greater expression of BMP-2 in the GSH+DM group than in the GM group. The results suggest that GSH promotes new peri-implant bone formation and osseointegration in diabetic rabbits.