Effect Of Lipopolysaccharide On Expresson Of Robo4/Slit2 And VE-cadherin In Human Umbilical Vein Endothelial Cells

Objective: To research the effect of different concentrations of Lipopolysaccharide(LPS) on the expression of Robo4, Slit2 and VE-cadherin in human umbilical vein endothelial cells(HUVECs). Methods: HUVECs were randomly divided into 3 groups: control group, low dose LPS(10 ug/ml) and high dose LPS(100 ug/ml) group, and cultured at 37 ℃for 24 h and 48 h. The Robo4 was detected by mmunofluorescence staining, the Robo4, Slit2 and VE-cadherin protein were detected by western blot, and the Robo4, Slit2 and VE-cadherin mRNA were measured by real-time PCR. Results: The Robo4, Slit2 and VE-cadherin protein in high dose LPS group after 24 h were 0.48±0.08、0.75±0.11、0.64±0.12, which were significantly decreased than those(1.36±0.11、1.64±0.17、1.55±0.15) in control group(P<0.05); The Robo4, Slit2 and VE-cadherin protein in high dose LPS group after 48 h were 0.20±0.04、0.32±0.09、0.27±0.09, which were significantly decreased than those at 24 h( P<0.05); The Robo4, Slit2 and VE-cadherin mRNA in high dose LPS group after 24 h were0.23±0.06、0.21±0.09、0.20±0.07,which were significantly decreased than those(0.97±0.13、0.89±0.12、0.85±0.13) in control group(P<0.05); The Robo4, Slit2 and VE-cadherin mRNA in high dose LPS group after 48 h were0.10±0.04、0.10±0.05、0.08±0.03,which were significantly decreased than those at 24 h(P<0.05); However, the Robo4, Slit2 and VE-cadherin protein and Robo4, Slit2 and VE-cadherin mRNA were no significant difference between the low dose group and the control group at 24 h and 48 h(P>0.05). Conclusion: High dose of LPS(100 ug/ml) can down-regulate the expression of Robo4, Slit2 and VE-cadherin in HUVECs,in a time and dose dependentmanner. The endothelial cell injury induced by LPS may be associated with down-regulation of Robo4 / Slit2 signal pathway; Robo4 / Slit2 signaling pathway may be closely related to associated with severe sepsis; the expression of Robo4 was may be a new biomarker to evaluate the severity and prognosis of sepsis.