Abstract:Objective To observe miRNA-140 expression in chondrocytes of patients with early osteoarthritis (OA)and the effect of transfecting double-stranded miR-140 (ds-miRNA-140) on chondrocyte function. Methods Normal and OA chondrocytes (4 weeks and 8 weeks) were collected from rabbit model of early OA (A, B and C group, respectively). Quantitative polymerase chain reaction was used to examine miRNA-140 expression and Western blotting analysis was used to examine Col2a1 and MMP-13 protein expression in each group. Col2a1 and MMP-13 protein expression was also observed in chondrocytes transfected with ds-miR-140. Results Compared with group A, miR-140 expressions in group B and C were reduced to 63% and 57%, respectively (P<0.01); the expression was not significantly different between the group B and C(P>0.05). Compared with group A, Col2a1 mRNA expressions in group B and C were reduced by 52% and 63%, respectively (P<0.01); while MMP-13 mRNA expressions were up-regulated by 3.01 and 4.15 folds, respectively (P<0.01). Transfection with ds-miR-140 increased Col2a1 mRNA by 60% and 127% in group B and C, respectively(P<0.01), and the expressions of MMP-13 mRNA in group B and C were reduced to 54.53% and 42.61%, respectively(P<0.01). The changes of Col2a1 and MMP-13 protein expression were the same as that of mPNA. Conclusion miR-140 expression is reduced in early OA cartilage, and transfection with ds-miR-140 may increase Col2a1 expression and reduce MMP-13 expression.