Effect of siRNA mediated by lentivirus silencing ERK2 on cartilage degeneration in rat models of post traumatic osteoarthritis and its mechanism

NING Rende; KONG Lingchao; ZHOU Yejin; WANG Xiang

doi:10.3969/j.issn.1002-266X.2016.16.001

Abstract：Objective To observe the effect of siRNA mediated by lentivirus silencing extracellular signal-regulated kinase 2 (ERK2) on cartilage degeneration in rat models of post-traumatic osteoarthritis and to investigate its mechanism . Methods Thirty light knees of traumatic osteoarthritis model rats were randomly divided into 3 groups with 10 rats in each group, then the right knee joint cavities of theirs were injected with sterile PBS (PBS group), negative ERK2 siRNA lenti-virus solution ( negative control group ) and ERK2 siRNA lentivirus solution ( observation group ) , respectively .After 8 weeks, the rats were sacrificed and the general morphology of the articular cartilage was observed and scored , then the ar-ticular cartilage pathological changes were observed under the optical microscope with HE , toluidine blue and safranin "O"staining, respectively, and the degree of cartilage degeneration was analyzed by Mankin semi-quantitative method.Mean-while, the relative mRNA expression of matrix metalloproteinase 3 (MMP3), MMP13 and Col2a of cartilage tissues was an-alyzed by real-time fluorescence quantitative PCR .Results The articular cartilage surface ulcers and defects in the obser-vation group were significantly lighter than those of the PBS group and negative control group , the extent of smooth articular surface of cartilage, crack area, loss of tissue, matrix staining, the proliferation of chondrocytes and the disorder of ar-rangement in the cartilage tissues of the observation group were lighter than those of the PBS group and negative control group;and the normal morphology and articular cartilage score in the observation group were significantly lower than those in the PBS group and negative control group (all P<0.05), there was no significant difference between the PBS and nega-tive control groups (P>0.05).In addition, the relative mRNA expression levels of MMP3 and MMP13 in the observation group were lower than those in the PBS group and negative control group , while the relative mRNA expression level of Col 2a was higher than that in the PBS group and negative control group (all P<0.01);there was no significant difference in the expression of MMP3, MMP13 and Col2a mRNA between the PBS group and negative control group (all P>0.05).Con-clusion siRNA mediated by lentivirus silencing ERK 2 can significantly reduce the cartilage degeneration of post-traumatic osteoarthritis , whose mechanism may be related with the decreased expression of MMP 3 and MMP13 and increased expres-sion of Col2a.