[Shikimic acid extracted from Chaenomeles speciosa reduces chondrocyte differentiation by inhibiting RBL-2H3 cell degranulation].

Objective To investigate the reducing effects of shikimic acid from the total extract of Chaenomeles speciose on the differentiation of chondrocytes into hypertrophic chondrocytes by inhibiting RBL-2H3 cell degranulation. Methods The chondrocytes were identified by toluidine blue staining and tryptase immunohistochemical staining. The chondrocytes were divided into normal chondrocytes control group, C48/80 activated RBL-2H3 cell culture supernatant treatment group, 3, 10 and 30 µg/mL SA activated RBL-2H3 cell culture supernatant treatment groups. The toxicity of SA and RBL-2H3 cell supernatant were detected by MTT assay. Western blotting was used to detect the expression of collagen type II (Col2) and collagen type X (Col10) in chondrocytes. The levels of matrix metalloproteinase 13 (MMP13), soluble nuclear factor B receptor activated protein ligand (sRANKL) and bone protective factor (OPG) were determined by ELISA, and glycosaminoglycan polysaccharide (GAG) were tested by dimethylmethylene blue (DMB) colorimetry. Results (0~30) µg/mL SA had no significant effects on the growth of chondrocytes. Compared with the C48/80 activated RBI-2H3 cell supernatant treatment group, the expression of Col2 and GAG proteins increased significantly, while the expression of Col10 and MMP13 and the ratio of sRANKL/OPG decreased significantly in the SA treatment groups in a dose-dependent manner. Conclusion SA can effectively reduce the differentiation of chondrocytes into hypertrophic chondrocytes by inhibiting RBL-2H3 cell degranulation.