Abstract: In this study,the effects of icaritin on chondrogenic differentiation of bone marrow mesenchymal stem cells induced by growth differentiation factor 5 were investigated.BMSCs were collected from Sprague Dawley rats.The morphology was observed by inverted microscope.rBMSCs at passage 3 were randomized divided into 4 groups:control group,Icaritin group,GDF-5 group,Icaritin+GDF-5 group and induced for 14 days.Alcian Blue stain showed the changes of proteoglycans;RT-PCR was used to detect the mRNA expression of Aggrecan,COL2,Sox9 and COL1;the protein expression levels of COL2 and COL1 were detected by Western Blot assay.The results indicated that,compared with the control group and GDF-5 group,Icaritin +GDF-5 group showed deeper proteoglycans staining;cartilage differentiation marker genes Aggrecan,COL2,Sox9 and the protein expression levels of COL2 significantly increased.Icaritin can promote chondrogenic differentiation of bone marrow mesenchymal stem cells induced by GDF-5.

Key words: icaritin, GDF-5, BMSCs, chondrogenic differentiation