Effects of Diosmin on IL-1 beta- Induced Inflammatory Response in Primary Rat Chondrocytes

Background and Objective: Diosmin, a bio-flavonoid present in the dietary supplement in citrus fruits. Due to its notable anti-inflammatory properties with less toxic effects, the potential chondroprotective activity was investigated. The aim was to investigate the chondroprotective activity of diosmin on IL-1 beta-stimulated inflammatory reaction in Primary Rat Chondrocytes (PRC) using an in-vitro model. Materials and Methods: PRCs were isolated and cultured followed by stimulation with IL-1 beta. The viability of cells was determined using an MTT assay. Nitric Oxide (NO) synthesis was estimated using the Griess Reaction (GR) method and the concentrations of PGE(2), MMP1, MMP13, TNF-alpha, IL-6 and COX-2 secreted by chondrocytes was assessed using the sandwich ELISA technique. Results: It was found that 50 and 100 mu g mL(-1) of diosmin had no effect on the viability of chondrocytes and were chosen for the study. The diosmin pre-treatment suppressed the induction of NO and PGE(2) in a dose-dependent manner. Conclusion: The results indicated that diosmin dose-dependently suppressed the inflammatory response by significantly reducing the production of NO, PGE(2), MMP1 and MMP13 in IL-1 beta challenged PRCs. Moreover, diosmin was able to cause the decrease in the levels of TNF-alpha, IL-6 and COX-2 in PRCs, thereby exhibiting the chondroprotective activity.