The Biological Behavior And Phenotypic Effect Of MiR-218/Slit-robo Signal Axis On Liver Sinusoidal Endothelail Cells

BackgroundThe liver is the body's largest digestive organ,which plays a crucial role in the body metabolism.Liver tissue damage,such as chronic inflammation and fibrosis,often results in systemic or even fatal metabolic disorders.On the other hand,the liver has a strong capacity of regeneration,which can compensate for the destruction of liver parenchyma.Research on liver damage and repair has never stopped.Liver Sinusoidal Endothelail Cells(LSECs)are some kind of liver tissue specific vascular endothelial Cells,its characteristic performance is the existence of fenestrate cell surface and the lack of vascular endothelial basement membrane.Liver Sinusoidal Endothelail Cells play an important role in maintaining the homeostasis of liver and pathological damage of liver.Previous studies have confirmed that Notch signal plays an important role in vascular development and angiogenesis.The Notch signal particularly activated in vessle plays a key role in maintaining the normal structure of hepatic vessels,the secretory function of blood vessels and the vascular remodeling after acute liver injury.The early studies on mir-218 /Slit-Robo signaling pathways are concentrated in the nervous system.With the advancement of technology,the Slit-Robo signaling pathway has been proved to play an important role in cell migration,inflammatory response,tumor occurrence,organ development and angiogenesis.ObjectiveTo determine whether the Mir-218/Slit-Robo signaling pathway is correlated with the Notch signal in the hepatic injury model,and to study the biological behavior and phenotypic effect of the Mir-218/Slit-Robo signal axis on the Liver Sinusoidal Endothelail CellsMethod1.Isolate and identify the original LSECs of mice preparing detecting the molecular expression of single cell level and cell transfection.2.By means of RT-PCR,western blot and immunofluorescence staining,detecting the expression of molecule related to miR-218/Slit-Robo signaling pathways in C57/NICD mice with partial hepatectomy and liver fibrosis model.3.By transfection of LSECs in C57 mice and interfering with mir-218 expression,the effects of mir-218 /Slit-Robo signaling pathway on the morphology of LSECs cells,cell proliferation,cell migration and other functions and behaviors were observed.Result1.The number of LSECs obtained from the separation was big,the activity was good,the purity was high,the fenestration was clear and obvious,and it had a strong endocytic function,and the surface markers of the endothelial cells were expressed.2.In the single-cell level and organizational level,the miR-218/Slit-Robo signaling pathways were showed significant change characteristics in LSECs as the liver tissue specificity of vascular endothelial cells.In the case of vascular specific activation of Notch signal,the expression of mir-218 and its host gene,Slit2,significantly increased,leading to significant down-regulation of the target gene Robo1 and Robo2.3.There was no significant difference in fenestration,cytoskeleton staining and cell migration capacity in LSECs after up-regulation of Mir-218,BUT the proliferation ability of cells was enhanced,and the expression of IL-6 which is one of the liver regeneration promoter was up-regulated.Conclusion1.Mir-218 is likely to be a key molecule which is in downstream of Notch signaling pathway,and plays an important role in the repair of liver injury by mediating the Slit-Robo signaling pathway.2.Mir-218 can promote the proliferation of Liver Sinusoidal Endothelail Cells and may influence the liver regeneration process by up-regulating IL-6.