Involvement of vascular endothelial growth factor signaling in CLR/RAMP1 and CLR/RAMP2-mediated pro-angiogenic effect of intermedin on human vascular endothelial cells
Intermedin (IMD) is a recently discovered peptide closely related to adrenomedullin. Its principal physiological activity is its role in the regulation of the cardiovascular system, where it exerts a potent hypotensive effect. In addition, data were recently provided showing that this peptide is able to exert a clearcut pro-angiogenic effect both in vitro and in vivo. IMD acts through the non-selective interaction with receptor complexes formed by the dimerization of calcitonin-like receptor (CLR) with the receptor activity-modifying proteins RAMP1, 2 or 3. Thus, in the present study, the role of CLR/RAMP complexes in mediating the pro-angiogenic effect induced by IMD on human umbilical vein endothelial cells (HUVECs) cultured on Matrigel was examined. Real-time PCR demonstrated the expression of IMD, CLR/RAMP1 and CLR/RAMP2 (but not CLR/RAMP3) mRNA in HUVECs. IMD exerted a significant in vitro angiogenic action, specifically triggered by the binding of the peptide to CLR/RAMP complexes. Both CLR/RAMP1 and CLR/RAMP2 appeared to mediate the pro-angiogenic effect, which was associated with a significant increase of vascular endothelial growth factor (VEGF) mRNA expression 18 h following IMD administration, indicating that the observed pro-angiogenic effects are related, at least in part, to an increased synthesis of this growth factor promoted by the peptide. Western blot analysis, however, showed a significant increase of VEGF receptor-2 phosphorylation as early as 5 min following IMD administration, indicating that IMD induces a pro-angiogenic response in human vascular endothelial cells not only via CLR/RAMP-induced release of VEGF, but also during signal initiation and propagation by transactivating the VEGF receptor-2 machinery.
No Reference information available - sign in for access.
No Citation information available - sign in for access.
No Supplementary Data.
No Article Media
Document Type: Research Article
Affiliations: Department of Human Anatomy and Physiology, Section of Anatomy, University of Padova-Medical School, I-35121 Padova, Italy
Publication date: January 1, 2010
More about this publication?
- The International Journal of Molecular Medicine is a monthly, peer-reviewed journal devoted to the publication of high quality studies related to the molecular mechanisms of human disease. The journal welcomes research on all aspects of molecular and clinical research, ranging from biochemistry to immunology, pathology, genetics, human genomics, microbiology, molecular pathogenesis, molecular cardiology, molecular surgery and molecular psychology.
The International Journal of Molecular Medicine aims to provide an insight for researchers within the community in regard to developing molecular tools and identifying molecular targets for the diagnosis and treatment of a diverse number of human diseases.
- Editorial Board
- Information for Authors
- Submit a Paper
- Subscribe to this Title
- Information for Advertisers
- Terms & Conditions
- Ingenta Connect is not responsible for the content or availability of external websites