Interaction of arterial cells. I. Endothelial cells alter cholesterol metabolism in co-cultured smooth muscle cells.

TitleInteraction of arterial cells. I. Endothelial cells alter cholesterol metabolism in co-cultured smooth muscle cells.
Publication TypeJournal Article
Year of Publication1985
AuthorsHajjar DP, Falcone DJ, Amberson JB, Hefton JM
JournalJ Lipid Res
Volume26
Issue10
Pagination1212-23
Date Published1985 Oct
ISSN0022-2275
KeywordsAnimals, Arteries, Carbon Radioisotopes, Cattle, Cells, Cultured, Cholesterol, Cholesterol Esters, Culture Media, Endothelium, Fibronectins, Humans, Kinetics, Lipoproteins, LDL, Muscle, Smooth, Vascular, Oleic Acid, Oleic Acids, Protein Biosynthesis, Tritium
Abstract

Results of previous in vivo experiments indicated that the presence of arterial endothelium modifies cholesteryl ester (CE) metabolism and the retention of low density lipoproteins (LDL) in injured arteries. We describe herein the effects of bovine arterial endothelial cells (ENDO) on the CE cycle, fluid phase endocytosis, and cell proliferation in co-cultured bovine arterial smooth muscle cells (SMC). Following several days of cultivation on confluent SMC, ENDO were removed from SMC by treatment of the co-cultures with 1.0% collagenase (type II). Removal of only ENDO from the co-culture dishes was confirmed by immunofluorescent staining for Factor VIII antigen, hemotoxylin-eosin staining, and biochemical analyses. We observed that ENDO grown to 75% confluency on confluent SMC induced: 1) a reduction of CE hydrolysis as a result of decreased lysosomal CE hydrolytic activity in SMC as compared to SMC cultured alone; and 2) an increase in the rate of incorporation of labeled oleate into CE as a result of increased acyl CoA:cholesterol O-acyltransferase activity in SMC as compared to SMC cultured alone. Neither endothelial cell-derived culture media (ECDM) nor fibroblasts modulated CE metabolism in co-cultured SMC. Additional experiments showed that the presence of endothelial cells or ECDM decreased the proliferation of co-cultured SMC by 50%, but enhanced the endocytotic rate of labeled sucrose into SMC threefold. Results of experiments described herein demonstrate that, in addition to providing a thrombo-resistant surface and regulating permeability, endothelial cells may also serve to modulate cholesteryl ester metabolism in smooth muscle cells derived from the arterial wall.

Alternate JournalJ Lipid Res
PubMed ID4067416
Grant ListHL-18828 / HL / NHLBI NIH HHS / United States
Related Faculty: 
David P. Hajjar, Ph.D. Domenick J. Falcone, Ph.D.

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