Polydatin Alleviates Lipopolysaccharide-Triggered Inflammatory Injury Through Up-Regulating miR-125b in Chondrogenic ATDC5 Cells

Osteoarthritis is a bone-joint disease prevalent in older people characterized by joint inflammation. In traditional Chinese medicine, polydatin plays an important anti-inflammatory role. This study analyzed the potential effects and possible internal mechanisms of polydatin on osteoarthritis. First, lipopolysaccharide-induced osteoarthritis injury was established in chondrogenic ATDC5 cells. Lipopolysaccharides significantly stimulated inflammatory injuries in ATDC5 cells as exemplified by a decrease in cell viability and an increase in inflammatory cytokine secretions including interleukin-6, tumor necrosis factor-a, and interleukin-1. Moreover, lipopolysacchrides also increased Cleaved caspase-3 and Cleaved Poly (ADP-ribose) polymerase to promote cell apoptosis. Second, polydatin showed significant protective effects against lipopolysaccharide-induced inflammatory injury, again exemplified by increased cell viability, decreased inflammatory cytokines, Cleaved caspase-3, and Cleaved poly (ADP-ribose) polymerase. Lastly, miR-125b and its binding target Rho-Associated Coiled-Coil Containing Protein Kinase 1 were closely associated with regulatory effects of polydatin against lipopolysaccharide-stimulated ATDC5 cell inflammatory injuries. Polydatin alleviated lipopolysaccharide-stimulated inflammatory injuries via the down-regulation of miR-125b. The present study concludes that polydatin plays an anti-inflammatory role in lipopolysaccharide-stimulated ATDC5 cell inflammatory injuries via the down-regulation of miR-125b.

Evaluation of Insulin Medium or Chondrogenic Medium on Proliferation and Chondrogenesis of ATDC5 Cells

Background. The ATDC5 cell line is regarded as an excellent cell model for chondrogenesis. In most studies with ATDC5 cells, insulin medium (IM) was used to induce chondrogenesis while chondrogenic medium (CM), which was usually applied in chondrogenesis of mesenchymal stem cells (MSCs), was rarely used for ATDC5 cells. This study was mainly designed to investigate the effect of IM, CM, and growth medium (GM) on chondrogenesis of ATDC5 cells.Methods. ATDC5 cells were, respectively, cultured in IM, CM, and GM for a certain time. Then the proliferation and the chondrogenesis progress of cells in these groups were analyzed.Results. Compared with CM and GM, IM promoted the proliferation of cells significantly. CM was effective for enhancement of cartilage specific markers, while IM induced the cells to express endochondral ossification related genes. Although GAG deposition per cell in CM group was significantly higher than that in IM and GM groups, the total GAG contents in IM group were the most.Conclusion. This study demonstrated that CM focused on induction of chondrogenic differentiation while IM was in favor of promoting proliferation and expression of endochondral ossification related genes. Combinational use of these two media would be more beneficial to bone/cartilage repair.