S100A8 And S100A9 Protein Promote Cell Proliferation Via RAGE

Objective:S100 Calcium Binding Protein A8(S100A8)and A9(S100A9)belong to the S100 family of calcium-binding proteins and play an important role in inflammation.We investigated the effect of S100A8/9 on human umbilical vein endothelial cells(HUVECs)and explored the role of S100A8/9 in venous endometrial remodeling.Method:1.Detecting the expression level of S100A8/9 in venous remodeling by analyzing the genetic data of animal models;2.We stimulate HUVECs by adding exogenous S100A8/9 protein,and observe cell’s proliferation,migration,and angiogenesis capacity by using CCK-8,Transwell migration experiments,and angiogenesis experiments;3.Flow cytometry was used to detect the effect of S100A8/9 on HUVECs cell cycle;4.Western Blot and qPCR analyzed PI3K/Akt/mTOR signaling pathway and mTORC2,then,their downstream molecules;5.RAGE blocking antibodies and small interfering RNA were used to investigate the role of RAGE and Rictor in the S100A8/9 signaling pathway.Result:1.We previously confirmed that S100A8/9 are consistently overexpressed at 1and 7 days after surgery in a rabbit vein graft model;2.S100A8/9 promote HUVECs proliferation,migration and angiogenesis ability;3.S100A8/9 stimulate PI3K/Akt/mTOR signaling pathway,and its related anti-apoptotic proteins Bcl-2 and mTORC2 signaling pathways;4.RAGE blocking antibodies and rapamycin significantly inhibited the PI3K/Akt/mTOR pathway activated by S100A8/9.In addition,RAGE blocking antibodies suppressed the activation of mTORC2,while rapamycin has little effect;5.Specific small interfering RNA that diminish Rictor or RAGE expression reduce the cell viability,migration and angiogenesis of HUVECs caused by S100A8/9;Conclusion:1.The expression of S100A8 and S100A9 were promoted in the rabbit vein graft mode.2.S100A8/9 promotes cell growth and angiogenesis by activating the PI3K/Akt/mTOR and mTORC2 pathways via RAGE.3.S100A8/9 stimulation of vascular endothelial cell proliferation may protect the integrity of the transplanted vein endothelial cells,thereby preventing the failure of vein transplantation caused by NIH.