RESUMEN
AIM:To investigate the effect of oleuropein on interleukin-1β( IL-1β)-induced SD rat articular chondrocytes .METHODS:The SD rat articular chondrocytes were isolated by 2 step enzyme digestions .The chondrocytes were cultured in vitro.Inverted microscopic observation was performed during the culture .Alcian blue staining and type II collagen immunohistochemical staining were used to identify the chondrocytes .The effects of oleuropein on the viability of chondrocytes were determined by CCK-8 assay.The cells in 3rd passage were pretreated with oleuropein at 10, 50 or 100 μmol/L and subsequently stimulated with IL-1βat 10 μg/L for 24 h.Production of prostaglandin E 2 ( PGE2 ) and ni-tric oxide (NO) were evaluated by the Griess reaction and an enzyme linked immunosorbent assay (ELISA).The mRNA expression of matrix metalloproteinase ( MMP)-1 and MMP-13 was measured by real-time PCR.The protein levels of in-ducible nitric oxide synthase (iNOS), cyclooxygenase-2 (COX-2) and nuclear factor-kappa B (NF-κB) were detected by Western blotting .RESULTS:The cell viability of chondrocytes was not significantly impaired by treating with oleuropein at concentration of 10, 50 or 100μmol/L for 24 h compared with control group .Pretreatment with oleuropein significantly in-hibited the production of PGE 2 and NO induced by IL-1β.Oleuropein also significantly decreased the IL-1β-stimulated MMP-1 and MMP-13 mRNA expression in articular chondrocytes .Pretreatment with oleuropein inhibited the IL-1β-media-ted activation of NF-κB by suppressing the degradation of its inhibitory protein IκBαin the cytoplasm .CONCLUSION:Oleuropein inhibits IL-1β-induced inflammatory gene expression by suppressing NF-κB activation at the transcriptional le-vel, suggesting a new mechanism for the anti-inflammatory effects of oleuropein as a novel agent on treating with osteoarthri-tis.