Macrophage conditioned medium induces the expression of C-reactive protein in human aortic endothelial cells: Potential for paracrine/autocrine effects

Senthil Kumar Venugopal, Sridevi Devaraj, Ishwarlal Jialal

Research output: Contribution to journalArticle

121 Scopus citations

Abstract

C-reactive protein (CRP) is a risk marker for cardiovascular events in apparently healthy persons. Cogent data show that, aside from the liver, CRP is produced in atherosclerotic lesions, kidney, neurons, and alveolar macrophages. Because several proatherogenic effects of CRP have been documented in endothelial cells, we examined human aortic endothelial cells (HAEC) for CRP production. We detected the presence of CRP mRNA by RT-PCR and in situ hybridization, intracellular protein by Western blot and secreted protein by ELISA. Coincubation with the cytokines interleukin (IL)-1, IL-6, and tumor necrosis factor alone and in combination showed that the most potent agonist for CRP production from HAEC is the combination of IL-1 and IL-6 (P < 0.05). To mimic the in vivo situation, we examined whether vascular smooth muscle cell (VSMC) and/or macrophage conditioned media (MCM) could augment CRP production by HAEC. While VSMC-conditioned media had no effect, incubation with MCM resulted in a significant twofold increase in the synthesis of both intracellular and secreted CRP (P < 0.05). The effect of MCM could be reversed by inhibiting both IL-1 and IL-6. Thus, stimulated synthesis and secretion of CRP by cells in the atherosclerotic lesion by paracrine/autocrine loops could result in local concentrations of CRP far in excess of plasma concentrations and could contribute to proinflammatory, proatherogenic effects.

Original languageEnglish (US)
Pages (from-to)1265-1271
Number of pages7
JournalAmerican Journal of Pathology
Volume166
Issue number4
StatePublished - Apr 2005

ASJC Scopus subject areas

  • Pathology and Forensic Medicine

Fingerprint Dive into the research topics of 'Macrophage conditioned medium induces the expression of C-reactive protein in human aortic endothelial cells: Potential for paracrine/autocrine effects'. Together they form a unique fingerprint.

  • Cite this