Under The Anaerobic Environment,Study On Calcitonin Effect Of Osteoclast And Molecular Mechanism

Objective:The study explains calcitonin regulates the adhesion of osteoclasts under the anaerobic environment,p38-MAPK-Erk signaling pathway in calcitonin molecular biology mechanism of inhibiting osteoclast function.To provide study basis on search for targeted treatment for bone metabolism diseases such as osteoporosis.Methods:The hypoxia model was established with 3%O₂,5%CO₂ and 92%N₂.Under the anaerobic environment,the osteoclasts without any stimulation are the hypoxic control group;stimulated with 10nmol/l calcitonin group;in advance to add 2μmol/L SB203580（p38 inhibitor）,37℃and 5%CO₂ training after 30 min,0.01 LPBS cleaning three times,then in hypoxia environment with 10 nmol/L calcitonin stimulus for p38 lightning inhibitor group.The osteoclasts cultured in normal environment without any stimulation are the normal control group.Each group detect cell proliferation optical density（OD）via CCK-8 test;detect apoptosis via Annexin V-FITC cell apoptosis experiment;detect cell migration change via Transwell cell migration experiment;detect each group protein expressing of osteoclasts type I collagen carboxy-terminal peptide via enzyme linked immunosorbent assay（ELISA）;detect each group proteins expression of p-p38/p38 and p-Erk/Erk in osteoclasts via Western blot;and detect each group protein content of p-p38/p38 and p-Erk/Erk in osteoclasts via enzyme linked immunosorbent assay（ELISA）.Results:The normal control group,hypoxic control group and calcitonin group are OD value of osteoclasts decreased gradually and there are significant differences（P<0.01）.The OD value of osteoclast proliferation in p38 inhibitor group higher than calcitonin group,and there are significant differences between them（P<0.01）.The apoptosis rate of osteoclast cells increased gradually in normal control group,hypoxic control group and calcitonin group.The difference was significant（P<0.01）.The apoptosis rate of osteoclast cells in p38 inhibitor group is lower than that in calcitonin group,there are significant differences between the two groups（P<0.05）.The cell migration rate of osteoclasts decreased gradually in the normal control group,hypoxic control group and calcitonin group.The difference was significant（P<0.01）.The cell migration rate of osteoclast cells in p38 inhibitor group was higher than that in calcitonin group,the difference was significant（P<0.01）.The protein expressions in osteoclasts of p-erk/Erk and p-p38/p38 in the normal control group and the hypoxic control group decreased gradually.There were significant differences between the two groups（P<0.01）.The protein expressions of p-erk/Erk and p-p38/p38 in calcitonin group are significantly higher than hypoxia control group,there were significant differences between the two groups（P<0.05）.The protein expressions of p-erk/Erk and p-p38/p38 in the p38 inhibitor group are significantly lower than those in the calcitonin group.There were significant differences between the two groups（P<0.05）.The CTX protein expression of osteoclasts decreased gradually in normal control group,hypoxia control group and calcitonin group.The difference was significant（P<0.01）.The CTX protein expression in p38 inhibitor group was significantly higher than that in calcitonin group.There are significant differences between them（P<0.05）.Conclusion:1.Calcitonin induced osteoclast proliferation and apoptosis in hypoxic environment.2.Calcitonin reduces bone resorption energy of osteoclasts in hypoxic environment.3.Calcitonin induces changes in biological activity of osteoclasts by activating the P38-MAPK-Erk signaling pathway.