Research on inhibitory role of CHR in TNF-αinduced high permeability in vascular endothelial cells

doi:10.3969/j.issn.1002-1949.2014.08.020

Abstract：Objective To explore the role of Chromogranin A ( CGA ) derived peptide CGA47-66 (Chromfungin, CHR) on TNF-αinduced hyperpermeability in vascular endothelial cells . Methods Human umbilical venous endothelial cell line ( EA.hy926 cells) was exposed respectively to CHR, TNF -α.Transwell assay, PCR and Western -blot were respectively performed to detect permeability of monolayer endothelial cells , expression of VE-cadherin mRNA and proteins , as well as expressions of permeability -related proteins such as phosphorylated p 38 MAPK and total p38 MAPK. Results Compared with blank control group , TNF-αproduced an obviously increased permeability in EA.hy926 cells (2.479 ±0.117 vs.1.769 ±0.554, t =3.543, P =0.008 ) and decreased the expression of VE-cadherin mRNA (1.145 ±0.035 vs.1.593 ±0.161, t=-4.707, P=0.035). CHR (1 nM, 10 nM, 100 nM) increased the expression of VE -cadherin mRNA (1.512 ±0.045, 1.615 ±0.170, 1.918 ±0.355 vs.1.162 ±0.189, P<0.05) , while CHR (1 nM, 10 nM, 100 nM, 1000 nM) alleviated high-permeability (1.954 ±0.379, 1.835 ±0.090, 1.430 ±0.349, 1.559 ± 0.447 vs.2.479 ±0.117, P<0.05) and low-expression of VE -cadherin mRNA (1.541 ±0.149, 1.529 ±0.098, 2.087 ±0.437, 1.640 ±0.160 vs.1.145 ±0.035, P<0.05) that induced by TNF-αin a dose-dependent manner .Furthermore, the low-expression of VE-cadherin proteins and up-regulation of phosphorylated p 38 MAPK proteins expressions in the TNF -αgroup were markedly attenuated in the presence of CHR .Conclusion In a dose-dependent manner , CGA47-66 ( CHR) may inhibit the high permeability of vascular endothelial cells induced by TNF -α.The CHR's effect of inhibition on TNF-αinduced vascular leakage may be related to the p 38 MAPK signal pathways .