Analysis of Bone Repair and Inflammatory Process Caused by Simvastatin Combined With PLGA+HA+βTCP Scaffold.

Abstract

This study evaluated the tissue and inflammatory responses to the use of simvastatin and poly(lactic-co-glycolic acid) + hydroxyapatite + β-tricalcium phosphate (PLGA+HA+βTCP) scaffold for bone repair. Two defects of 5 mm in diameter were made in the calvaria of rats, which were shared into the following 6 groups: naive, sham, vehicle, PLGA+HA+βTCP scaffold, simvastatin (4 mg/mL), and simvastatin with the scaffold. Tissue samples were collected at 1, 7, 15, 30, and 60 days after surgery. Inflammation was evaluated by interleukin-1 beta and tumor necrosis factor alpha quantification and by a hemogram, whereas bone repair was evaluated using densitometry and scanning electron microscopy. Data were statistically analyzed using ANOVA followed by post hoc tests (P < 0.05). There was an increased cytokine expression in the scaffold and simvastatin groups (P < 0.001 and P < 0.05, respectively) 1 day after surgery but no alterations on the hemogram were observed. It was found on bone tissue samples that 60 days after surgery all groups presented similar densitometry values and morphology characteristics, despite the occurrence of bone formation delay in the simvastatin group (P < 0.01). The use of simvastatin and PLGA+HA+βTCP scaffold, associated or not, did not lead to improvement in bone repair.