MicroRNA-145 Is Involved In The Inflammatory Processes By Disturbing The Proliferative/Apoptotic Balance Of Macrophages

PartⅠmiR-145 modulates monocyte-macrophage proliferation and apoptosisObjective:To evaluate the role of miR-145 in monocyte-macrophage proliferation and apoptosis.Methods:After transfected with miR-145 precursor or inhibitor, cell proliferation was assessed by XTT and growth curve. For apoptosis assay, we performed TUNEL assay and immunofluorescence. Then we isolated bone marrow mononuclear cell from OPG knock-out mice, and evaluated the role of miR-145 in cell proliferation and apoptosis using XTT and Annexin V/PI assay. Lastly, we studied the effects of miR-145 on cell proliferation and apoptosis associated proteins.Results:Inhibition of miR-145 promoted cell proliferation and prevented apoptosis. Whereas, over-expression of miR-145 promoted cell apoptosis.Conclusion: miR-145 modulates monocyte-macrophage proliferation and apoptosis. Part IImiR-145 is involved in the metaflammation processesObjective: To clarify the role of miRNAs in the diabetic metaflammation processes.Methods:After jugular vein catheterization, mice were randomly divided into three groups and injected intravenously with PBS, miR-145 or miR-145 ASO for 3 days. We isolated the bone marrow mononuclear cells and performed the proliferation assay. Liver sections were stained by the macrophage specific marker F4/80 and the proliferation marker proliferating cell nuclear antigen (PCNA). We tested the expression of inflammatory factors using ELISA and cytokine microrray.Results:Mice administered with miR-145 ASO showed significantly higher proliferation compared to control and miR-145 groups. Macrophage marker F4/80 and the proliferation marker PCNA were higher in miR-145 ASO treated mice. The expression of TNF-α, MCP-1 in the liver tissue and several inflammatory factors in serum were elevated in miR-145 ASO injected mice.Conclusion:miR-145 is involved in the metaflammation processes by modulating monocyte-macrophage proliferation/apoptosis balance. PartⅢInvestigate the expression of miR-145 in populationObjective:To identify the expression of miR-145 in diabetic, IGT and normal persons.Methods:Blood samples were obtained from normal subjects, newly diagnosed impaired glucose tolerance and type 2 diabetic patients without treatment with hypoglycemic agents in community. We isolated blood mononuclear cell and examined the expression of miR-145 using quantitative PCR. We evaluated the levels of serum OPG by ELISA, and tested whether the levels of OPG were related to miR-145 expressions in the human.Results:We found that miR-145 in peripheral blood mononuclear cells of diabetic patients was down-regulated. And serum OPG levels were elevated in type 2 diabetic patients. A significant negative correlation between serum OPG and relative amount of miR-145 in the full set of 50 human samples was found. There was no significant difference between IGT and normal groups.Conclusion:miR-145 was down-regulated in diabetic subjects and negatively associated with serum OPG levels.