Activation and suppression of renin-angiotensin system in human dendritic cells

We previously identified the gene expression of renin-angiotensin system in human monocyte-derived dendritic cells (DCs). This study was conducted to examine the mechanisms by which angiotensin II and captopril, the inhibitor of the angiotensin-converting enzyme (ACE), affect human DCs. In DCs, lipopolysaccharide (LPS)-induced production of tumor necrosis factor-alpha (TNF-alpha), interleukin-(IL)-1alpha, IL-10, IL-12, and IL-18 was significantly inhibited by captopril. In contrast, angiotensin II treatment resulted in a significant increase in TNF-alpha and IL-6 protein biosynthesis by DCs. In addition, we have studied the global expression of 2400 genes in DCs from two donors. Here, we demonstrated the specific down-regulation of the ACE gene expression in captopril-treated DCs. Our finding indicates the possible activation of NF-kappaB through the up-regulation of expressions of MEFV gene (encoding PYRIN protein) and heterogeneous nuclear ribonucleoprotein R in DCs. This is the first study on the modulation of cytokine and gene expression by angiotensin II and captopril in DCs.