Establishment Of CIA Mouse Model And Effect Of Injection Of AgomiR-145-5p On Ankle Bone Erosion

Purpose Rheumatoid arthritis(RA)is a type of autoimmune disease.The main features of RA are chronic inflammation and destruction of articular cartilage and bone.In severe cases,other complications are induced and even disabling.The study found that microRNAs are involved in immune response and play an important role in the progression of RA disease.Our previous study found that miR-145-5p is associated with osteoarthritis(OA)synovial tissue and synovial cells in RA peripheral blood mononuclear cells(PBMC),synovial tissue,and fibroblasts in RA.The level of miR-145-5p was significantly increased in synovial cells(FLS)and regulated the expression of matrix metalloproteinase MMP.Therefore,this subject will establish a collagen-induced arthritis CIA mouse model,injection of agomiR-145-5p,observe the changes of ankle bone erosion in CIA mice,and explore the role of miR-145-5p in CIA.Methods CIA was induced by bovine type II collagen immunization with DBA/1 mice,and the joint index score and the degree of swelling of the foot were compared.After modeling,the mice were randomly divided into the agomiR-145-5p group and the agomiR empty vector(agomiR-NC)group.Using paw micro-CT,paraffin section,HE staining,and detecting metalloproteinase-1(MMP-1)and metalloproteinase-3(MMP-3)in the ankle joint by immunohistochemistry(IHC).Expression of metalloproteinase-9(MMP-9)and metalloproteinase-13(MMP-13).Results1 Model establishment and changes in arthritis score index Modeling DBA/1,approximately 85% of mice successfully established a CIA model with arthritic symptoms in the foot.2 mouse foot changes The mice in the miR-NC group showed normal pink color and no swelling in the joints.The affected mice had thickened feet and multiple joints.Collagen-induced successful mouse foot thickness and foot volume were higher than miR-NC groupmice3 HE staining to observe the therapeutic effect of miR-145-5p on articular cartilage injury in CIA miceCompared with the miR-NC group,the mouse synovial tissue of the agomiR-145-5p group was hypertrophied and hypertrophied.There were a large number of lymphocytes and a small amount of neutrophil infiltration in the connective tissue around the synovium,which was rich in blood vessels.The formation of tendons,articular cartilage and subchondral bone erosion are severely damaged.Compared with the agomiR-NC group,bone destruction was significantly enhanced in the agomiR-145-5p group(P<0.05).4 micro-CT scan to evaluate the effect of miR-145-5p treatment on joint damage in CIA miceCompared with the miR-NC group,both the agomiR-145-5p group and the agomiR-NC group showed bone erosion of the ankle joint;compared with the agomiR-NC group,the bone erosion was more serious in the agomiR-145-5p group.5 immunohistochemistryin the posterior sputum of the agomiR-145-5p group were increased,and there was no difference in MMP-1 levels.Conclusion In this experiment,bovine type II collagen was used to immunize DBA/1 mice to induce CIA mouse model.The joint index score and the degree of swelling of the foot were compared.The mice developed RA-related symptoms and successfully established the CIA model.Through joint scoring,micro-CT analysis,pathological analysis and immunohistochemistry,it was found that miR-145-5p aggravated the joint destruction of CIA mice,and found MMP-1,MMP-3,MMP-9 in the ankle joint.The expression of MMP-13 was higher than that of the agomiR-NC group.The levels of MMP-3,MMP-9 and MMP-13 in the posterior sputum of the agomiR-145-5p group were increased,and there was no difference in MMP-1 levels.