Role Of LncRNA In The Inflammatory Progress Of Chondrocytes Regulated By Mechanical Strain

Objective 1.The first part of the research intends to the explore appropriate dose of IL-1? to induce inflammatory reaction in chondrocytes;observe the effect of IL-1? on autophagy of chondrocytes.2.The second part of the research is to observe the influence of mechanical strain on autophagy of chondrocyte in inflammatory response.3.The third part of the research aims to observe the influence of mechanical strain on Lnc RNA-MEG3 expression in chondrocytes;explore the mechanism of mechanical strain regulating the autophagy of chondrocytes in inflammatory response.Methods 1.Chondrocytes harvested from newborn Sprague Dawley rats were treated with different dose of IL-1?.The expression of type II collagen(Col-2),matrix metalloproteinase(MMP13),autophagy-associated protein LC3 and Beclin-1 were detected by Real-time PCR and Western Blot.2.The chondrocytes were subjected to 2000 ?strain,5000 ?strain mechanical strain at a frequency of 1Hz for 2h with the Four-point Bending System.Real-time PCR and Western Blot were used to detect the expression of Col-2,MMP13,autophagy-associated protein p-m TOR,LC3 and Beclin-1.The formation of autophagosomes were detected under fluorescence microscopy after transfected by autophagy adenovirus.3.The expression of lnc RNA-MEG3 in chondrocytes was detected by Real-time PCR after treated with mechanical stimulation.The si-RNA was used to silence MEG3 and Real-time PCR was used to detect the expression of LC3 and Beclin-1.Results 1.The expression of Col-2 was down-regulated while MMP13 up-regulated after being treated with IL-1?.The expression of LC3 and Beclin-1 were up-regulated treated with low dose IL-1?,while p-m TOR was up-regulated by high dose IL-1?.2.The expression of Col-2 and LC3 were significantly up-regulated in 2000 ?strain group compared with 5000 ?strain group and control group(P<0.05).The relative expression of LC3II/I and Beclin-1 were higher than that of the 5000 ?strain group.The expression of p-m TOR in the 2000 ?strain group was lower than that in the 5000 ?strain group(P<0.05);the formation of autophagosomes in the 2000 ?strain group were much more compared with the control group and the 5000 ?strain group(P<0.05).3.The expression of MEG3 in chondrocytes was corelated with LC3 when treated with mechanical strain.The expression of MEG3 in chondrocytes subjected to mechanical stimulation in 2000 ?strain group was much lower than that in control group and 5000 ?strain.After silencing MEG3,the expression of LC3 and Beclin-1 increased significantly(P<0.05).Conclusion 1.IL-1? stimulated chondrocyte inflammatory reaction,5ng/m L IL-1? could be used to construct inflammatory chondrocyte model;low concentration of IL-1? promoted autophagy of chondrocytes.2.Low-intensity cyclic mechanical strain promotes the maintenance of the phenotype of chondrocytes in an inflammatory environment and promotes autophagy of chondrocytes.3.Mechanical strain can affect the expression of Lnc RNA-MEG3 and regulate the autophagy of chondrocytes in inflammatory response.