Naringin protects against bone loss in steroid-treated inflammatory bowel disease in a rat model.

We observed the effects of naringin on bone loss in glucocorticoid-treated inflammatory bowel disease (IBD) in a rat model. The IBD model was established in Sprague-Dawley rats by administering 5.0% dextran sodium sulfate. Dexamethasone (DEX) and naringin were given at the second week. Blood, colon and bone samples were collected for biomarker assay, histological analysis or microCT analysis. Superoxide dismutase, catalase and malonaldehyde were measured in bone. A significant decrease of procollagen type 1 N-terminal propeptide (P1NP) level was observed in DEX-treated IBD groups compared with the control (p < 0.05). P1NP levels were dose-dependently increased in the presence of naringin intervention. Bone loss and decreased bone biomechanical properties were observed in DEX-treated IBD rats compared with control rats (p < 0.01). Naringin intervention protected against bone loss and decreased bone biomechanical properties. Bone formation related gene mRNA expressions were significantly decreased in DEX-treated IBD rats compared with control rats. Naringin administration reversed the down-regulation of the expressions of those genes. Naringin treatment reduced the oxidative stress in bone from DEX-treated IBD rats. Our data indicated that naringin may have great potential for the treatment of bone loss in glucocorticoid-treated IBD patients via blocking oxidative stress and promoting bone formation.