This renewal application requests support to study the mechanisms involved in the regulation of human endothelial cell senescence in vitro. Prior observations from our laboratory and others have established that human endothelial cell growth is regulated by the signal-less heparin-binding fibroblast growth factor (HBGF) prototypes while human endothelial cell quiescence is regulated by polypeptide cytokines including interleukin (IL)-1alpha. Recent efforts have suggested that the repression of translation of IL-1alpha significantly extends the lifespan of the human umbilical vein endothelial cell (HUVEC) in vitro. These studies also suggest that the mechanism utilized by IL-1alpha to regulate HUVEC senescence involves the potential function of the signal sequence-less IL- 1alpha precursor to act as an intracellular modifier of the non-terminal HUVEC differentiation pathway. Thus, two specific aims are proposed to further define the role of IL-1alpha in HUVEC senescence. The first specific aim proposes to study the relevance of these observations to other types of human endothelial cells in vitro and are a natural extension of our prior research effort. These studies are straightforward and include the use of cell and molecular methods to define correlates between human endothelial cell senescence in vitro and the in vivo age of the donor. Because IL-1alpha is a potent inflammatory signal in vivo, these studies may provide insight into basic mechanisms involved in the regulation of vascular disease in the elderly. The second specific aim is more speculative because it is limited by our knowledge of the mechanism used by signal-less cytokines and growth factors to regulate cellular function. Our long-term goal is to understand how the signal-less IL-1alpha precursor regulates HUVEC function. Using molecular methods, we propose to identify a putative nuclear translocation signal within the structure of the precursor. In addition, we will attempt to identify and characterize the structure of intracellular polypeptides that are able to interact with the IL-1alpha precursor. While we suggest that IL-1alpha may act as an intracellular modifier of HUVEC quiescence and senescence, we also recognize that an alternative secretory pathway may exist and we propose to study this issue using our recent observation that heat-induced binding proteins may act as a vehicle for the secretion of HBGF-1. We anticipate that these efforts may provide insight into the mechanism(s) used by intracellular IL-1alpha to regulate human endothelial cell senescence in vitro and aid our understanding of the contribution of the vasculature to the aging process in vivo especially when the pathophysiology is exaggerated by inflammation and angiogenesis.

Agency
National Institute of Health (NIH)
Institute
National Institute on Aging (NIA)
Type
Research Project (R01)
Project #
5R01AG007450-05
Application #
3118558
Study Section
Pathology A Study Section (PTHA)
Project Start
1989-05-01
Project End
1996-04-30
Budget Start
1993-05-10
Budget End
1994-04-30
Support Year
5
Fiscal Year
1993
Total Cost
Indirect Cost
Name
American National Red Cross
Department
Type
DUNS #
003255213
City
Washington
State
DC
Country
United States
Zip Code
20006
Prudovsky, Igor; Bagala, Cinzia; Tarantini, Francesca et al. (2002) The intracellular translocation of the components of the fibroblast growth factor 1 release complex precedes their assembly prior to export. J Cell Biol 158:201-8
Wong, M K; Prudovsky, I; Vary, C et al. (2000) A non-transmembrane form of Jagged-1 regulates the formation of matrix-dependent chord-like structures. Biochem Biophys Res Commun 268:853-9
Prudovsky, I; Landriscina, M; Soldi, R et al. (2000) Fusions to members of fibroblast growth factor gene family to study nuclear translocation and nonclassic exocytosis. Methods Enzymol 327:369-82
Landriscina, M; Prudovsky, I; Mouta Carreira, C et al. (2000) Amlexanox reversibly inhibits cell migration and proliferation and induces the Src-dependent disassembly of actin stress fibers in vitro. J Biol Chem 275:32753-62
LaVallee, T M; Prudovsky, I A; McMahon, G A et al. (1998) Activation of the MAP kinase pathway by FGF-1 correlates with cell proliferation induction while activation of the Src pathway correlates with migration. J Cell Biol 141:1647-58
McMahon, G A; Garfinkel, S; Prudovsky, I et al. (1997) Intracellular precursor interleukin (IL)-1alpha, but not mature IL-1alpha, is able to regulate human endothelial cell migration in vitro. J Biol Chem 272:28202-5
Zimrin, A B; Pepper, M S; McMahon, G A et al. (1996) An antisense oligonucleotide to the notch ligand jagged enhances fibroblast growth factor-induced angiogenesis in vitro. J Biol Chem 271:32499-502
Garfinkel, S; Wessendorf, J H; Hu, X et al. (1996) The human diploid fibroblast senescence pathway is independent of interleukin-1 alpha mRNA levels and tyrosine phosphorylation of FGFR-1 substrates. Biochim Biophys Acta 1314:109-19
Garfinkel, S; Hu, X; Prudovsky, I A et al. (1996) FGF-1-dependent proliferative and migratory responses are impaired in senescent human umbilical vein endothelial cells and correlate with the inability to signal tyrosine phosphorylation of fibroblast growth factor receptor-1 substrates. J Cell Biol 134:783-91
Garfinkel, S; Brown, S; Wessendorf, J H et al. (1994) Post-transcriptional regulation of interleukin 1 alpha in various strains of young and senescent human umbilical vein endothelial cells. Proc Natl Acad Sci U S A 91:1559-63

Showing the most recent 10 out of 15 publications