The Effects Of PTH(1-34) On The Progress Of Mouse Oteoarthritis And The Activity Of STAT3 Signaling Pathway

Objectives The purpose of this experiment was to preventively give Parathyroid Hormone(PTH)(1-34)to intervene in the knee joint degeneration model of C57 Bl / 6 mice induced by type VII collagenase and observe PTH Effects on osteoarthritis(OA)articular cartilage and subchondral bone in mice and its effect on STAT3 signaling pathway activity.Methods Eighteen 12-week-old male C57 Bl / 6 mice were randomly divided into three groups: Sham group,OA group and PTH group,with 6 mice in each group.Experimental mice in the OA group were injected with 1U type VII collagenase on the first day of the left and right knee joints,and then injected again two days later(a total of two times).The OA model of the PTH group is the same as that of the OA group.After the OA model,the PTH(1-34)intervention is given prophylactically at a dose of 10 μg / kg,5 days a week.Six weeks after the prophylactic administration,the three groups of experimental mice were sacrificed.Subsequently,the knee joints of the three groups of mice were examined by Micro-CT bone morphology,toluidine blue staining and OARSI histological score,Col-II,ADAMTS-4,JAK2,STAT3 and other factors for immunohistochemical staining and IOD score.All experimental data are statistically analyzed by SPSS20.0 statistical analysis software.Results 1 Micro-CT results: Compared with the Sham group,the subchondral bone mineral density(BMD),bone volume fraction(BV / TV)and trabecular bone thickness(Tb.Th)of the OA group were significantly reduced(P=0.004,P=0.02,P=0.039 respectively);compared with OA group,BMD,BV / TV and Tb.Th of subchondral bone in PTH group were significantly increased(P<0.001,P<0.001,P=0.013 respectively).2 OARSI histological score: Compared with mice in the Sham group,the OA group had cracks and damage on the surface of the articular cartilage,chondrocyte cloning in some areas,and a decrease in local extracellular matrix staining.(P=0.002);compared with mice in the OA group,the articular cartilage surface of the PTH group was relatively complete,chondrocytes were neatly arranged,and the extracellular matrix was stained evenly,and the histological score was significantly reduced(P=0.004).3 IOD score of articular cartilage: Compared with the Sham group,the expression level of Col-II(P<0.001)at the tibial plateau of the OA group was significantly decreased,while the expression levels of ADAMTS-4,JAK2 and STAT3 were significantly increased(P=0.001,P<0.001,P=0.001).Compared with the OA group,the expression level of Col-II in the tibial plateau of the PTH group was significantly increased(P<0.001),and the expression levels of ADAMTS-4,JAK2,and STAT3 were significantly reduced(P=0.001,P=0.011,P=0.011 respectively).P<0.05 indicates statistical significance.Conclusions 1 Preventive administration of PTH(1-34)drugs to intervene in the knee joint degeneration model induced by type VII collagenase in C57 Bl / 6 mice can alleviate early OA cartilage degeneration and inhibit its subchondral bone loss.2 This effect may be related to PTH(1-34)inhibiting the STAT3 signaling pathway,promoting the synthesis and metabolism of extracellular matrix of articular cartilage and inhibiting its catabolism.Figure 5;Table 3;Reference 139...