Abstract
Endothelial cell function is regulated by interactions among cells, the extracellular matrix (ECM), and soluble mediators. We investigated this interaction by examining the effect of 17β-estradiol (E2) on release of basic fibroblast growth factor (FGF-2) by human coronary artery endothelial cells (HCAEC) cultured on ECM proteins. After estrogen-depleted HCAEC were treated with E2 for 2 h, the conditioned media and cell layers were evaluated by immunoblot or ELISA for FGF-2. Release of FGF-2 into conditioned media was enhanced 10-fold compared to that on plastic and a further 2.4-fold by E2. As FGF-2 release from cells into the media increases, there is a corresponding decrease in the cellular content of FGF-2. By ELISA, FGF-2 release increased 406, 179, and 262%, on type IV collagen, laminin, or fibronectin, respectively. HCAEC cultured on type I collagen did not show E2-enhanced FGF- 2 release by ELISA or immunoblot analysis. No changes were noted in HCAEC release of lactate dehydrogenase, tested as a control protein for cellular integrity. The estrogen receptor antagonist ICI182,780 blocked E2-induced, but not basal, FGF-2 release. Increased FGF-2 release occurred via a cycloheximide-insensitive pathway. Neither brefeldin-A nor genistein inhibited E2 enhancement of FGF-2 release by HCAEC cultured on fibronectin. However, the protein kinase C inhibitor calphostin C inhibited the E2- augmented FGF-2 release. These data show that E2 enhances FGF-2 release by HCAEC cultured on basement membrane proteins in the absence of wounding. This action requires the estrogen receptor and PKC activity, but does not require new protein synthesis, endoplasmic reticulum-to-Golgi-mediated secretion, or protein tyrosine phosphorylation. E2-enhanced FGF-2 release could contribute to the cardioprotective effects of estrogen.
| Original language | English (US) |
|---|---|
| Pages (from-to) | 163-169 |
| Number of pages | 7 |
| Journal | Experimental Cell Research |
| Volume | 245 |
| Issue number | 1 |
| DOIs | |
| State | Published - Nov 25 1998 |
Funding
This work was supported by Grants HL53918 from the National Heart, Lung, and Blood Institute, DK49362 from the National Institute of Diabetes, Digestive, and Kidney Diseases, and Children’s Memorial Hospital. Dr. Steven Vose provided ICI182,780, and Dr. Hynda Kleinman provided laminin. We also appreciate technical assistance by Ms. Susan Hubchak in cell culture methodology. This research was presented in part at the meetings of the Society for Pediatric Research, Washington, DC, May 1996, and Experimental Biology, New Orleans (LA), April 1997. Supported by Grants HL-53918 from the National Heart Lung and Blood Institute and DK-49362 from the National Institute of Diabetes, Digestive, and Kidney Diseases, Northwestern Memorial Hospital Intramural Research Grants Program, Children’s Memorial Hospital, and the Children’s Memorial Institute for Education and Research. 1To whom correspondence and reprint requests should be addressed at Northwestern University—Chicago, Pediatrics W-140, 303 E. Chicago Ave., Ward 12-110, Chicago, IL 60611-3008. Fax: (312) 503-1181. E-mail: [email protected].
Keywords
- Endothelial cell
- Extracellular matrix
- FGF-2
- Signal transduction
ASJC Scopus subject areas
- Cell Biology