Intestinal fatty acid-binding protein expression stimulates fibroblast fatty acid esterification.
The effect of intestinal fatty acid binding protein (I-FABP) expression on cell growth and cell lipid content is not known. Therefore, mouse L-cell fibroblasts were transfected with the cDNA encoding for I-FABP. The high expression clones expressed 0.35% of the total cytosolic proteins as I-FABP. Mock transfected L-cells did not differ from control L-cells in any properties tested. Neither the growth rate, maximal cell density, nor [3H]oleic acid uptake differed in I-FABP expressing as compared to control cells. In contrast, I-FABP expression increased triacylglycerol and cholesteryl ester mass (nmol/mg protein) by 63% and 25%, respectively. Phospholipid mass was unchanged in I-FABP expressing cells. The initial [3H]oleic acid esterification into triacylglycerols and cholesteryl esters was increased 3.9- and 2.5-fold in I-FABP expressing cells. Although, the initial [3H]oleic acid esterification into total phospholipids was unchanged, within the phospholipid fraction the initial [3H]oleic acid esterification into phosphatidylethanolamine was increased 70% and decreased 50% in phosphatidylcholine in I-FABP expressing cells. These observed differences suggest a distinct role for I-FABP in stimulating net formation, and not just turnover, of triacylglycerides and cholesteryl esters in transfected L-cell fibroblasts.
Prows
D R
DR
Division of Pharmacology and Medicinal Chemistry, University of Cincinnati, College of Pharmacy, OH 45267-0004, USA.
Murphy
E J
EJ
Moncecchi
D
D
Schroeder
F
F
D000818:Animals; D002352:Carrier Proteins / Q000235:genetics* / Q000494:pharmacology; D002455:Cell Division / Q000187:drug effects; D002784:Cholesterol / Q000378:metabolism; D002788:Cholesterol Esters / Q000378:metabolism; D018076:DNA, Complementary / Q000235:genetics; D004952:Esters / Q000378:metabolism*; D000071438:Fatty Acid-Binding Protein 7; D050556:Fatty Acid-Binding Proteins; D005227:Fatty Acids / Q000378:metabolism*; D005347:Fibroblasts; D005786:Gene Expression Regulation / Q000235:genetics*; D007422:Intestines / Q000737:chemistry; D050356:Lipid Metabolism; D051379:Mice; D018996:Myelin P2 Protein / Q000235:genetics* / Q000494:pharmacology; D009363:Neoplasm Proteins; D009419:Nerve Tissue Proteins; D019301:Oleic Acid / Q000378:metabolism; D014162:Transfection / Q000235:genetics; D014280:Triglycerides / Q000378:metabolism
D002352:Carrier Proteins; D002788:Cholesterol Esters; D018076:DNA, Complementary; D004952:Esters; C082667:Fabp5 protein, mouse; C086936:Fabp7 protein, mouse; D000071438:Fatty Acid-Binding Protein 7; D050556:Fatty Acid-Binding Proteins; D005227:Fatty Acids; D018996:Myelin P2 Protein; D009363:Neoplasm Proteins; D009419:Nerve Tissue Proteins; D014280:Triglycerides; D019301:Oleic Acid; D002784:Cholesterol