Original ArticleNanoparticle mediated PPARγ gene delivery on dental implants improves osseointegration via mitochondrial biogenesis in diabetes mellitus rat model

Diabetes mellitus (DM) has a detrimental effect on osseointegration, stability and longevity of implants due to osteoporosis. In this study, PPARγ-loaded dental implants were investigated for the improvement of osseointegration and peri-implantitis. Chitosan gold nanoparticles conjugated with PPARγ cDNA were introduced on titanium mini-implant surfaces for PPARγ release to rat mandibular. DM-induced rat mandible showed structural changes such as decreased bone mass and increased inflammatory molecules, and diminution of PPARγ expression and bone formation molecules compared to normal rats. PPARγ induced bone formation via reduction of inflammatory molecules even under glucose oxidative stress. Furthermore, PPARγ strongly activated mitochondrial biogenesis and cell viability via p-AMK and Wnt/β-catenin signaling. Consequently, PPARγ gene delivery on regional dental implants contributed osseointegration, new bone formation and mineralization in DM-induced rats. This study demonstrates that PPARγ can be used as a therapeutic gene with dental implantation in diabetic patients since regional PPARγ expression enhances osseointegration and implant longevity.

The lower first molar of experimental SD Rat was extracted carefully to avoid damage to the extraction socket. The alveolar bone had healed well one month after the extractions. Pure Ti mini screws with a length of 4.5 mm and a diameter of 0.85 mm were used as in vivo dental implants. The cDNA of LacZ and PPARγ were conjugated with Ch-GNPs and loaded onto mini-implants surface that immersed 10 times in a nanoparticle-DNA solution and frozen at −40 °C. The implant placement was performed and DM was induced after implantation 3 days later by an IP injection of STZ. IHC and μCT were performed for osseointegration. PPARγ loaded dental implant increased implant longevity and osseointegration.315