Angiotensin II stimulates endothelial integrin β3 expression via nuclear factor-κB activation

The present study examined the effect and part mechanism of angiotensin II - stimulated integrin beta(3) gene expression in human umbilical vein endothelial cells. Protein level and mRNA level of integrin b3 expression were determined using enzyme-linked immunoadsorbent assay and reverse transcription - polymerase chain reaction. Four plasmids of 5'-different deletion of integrin beta(3) gene promoter were constructed to transiently transfected into cells to uncover the region in response to angiotensin II. Blockade of nuclear factor-kappa B (NF-kappa B) signaling pathway effect on integrin beta(3) expression was analyzed by cotransfection with mutant plasmids for NF-kappa B-inducing kinase, inhibitory proteins a and beta of NF-kappa B kinase, respectively, together with the integrin b3 plasmid including the sequence - 1486 similar to -900. The study found that 10(-8) mol/L, 10(-7) mol/L, 10(-6) mol/L, and 10(-5) mol/L angiotensin II increased integrin b3 protein level by 45%, 52%, 62%, and 73% respectively. Angiotensin II at 10(-6) mol/L increased integrin beta(3) mRNA level by 67%. The luciferase activity of the integrin b3 plasmid PGL3 - 1486 similar to - 900 increased by 84.72% in response to angiotensin II. N-acetylcysteine blocked angiotensin II - induced NF-kappa B activity and integrin beta(3) expression. Blockade of NF-kappa B signaling pathway abolished the stimulation of angiotensin II. These results suggest that angiotensin II stimulates integrin beta(3) expression partly by NF-kappa B activation.