Reduced secretion of triacylglycerol in CaCo-2 cells transfected with intestinal fatty acid-binding protein.
The fatty acid-binding proteins are hypothesized to be involved in cellular fatty acid transport and trafficking. We established CaCo-2 cells stably transfected with intestinal fatty acid-binding protein (I-FABP) and examined how the expression of this protein may influence fatty acid metabolism. I-FABP expression was detectable in I-FABP-transfected cells, whereas parent CaCo-2 cells as well as mock-transfected cells failed to express detectable levels of I-FABP mRNA or protein at any stage of differentiation. For studies of lipid metabolism, cells were incubated with [14C]oleic acid in taurocholate micelles containing monoolein, and distribution of labeled fatty acid in cellular and secreted lipids was examined. In one transfected cell clone, expressing the highest level of I-FABP, labeled cellular triacylglycerol increased approximately twofold as compared to control cells. The level of intracellular triacylglycerol in two other I-FABP-transfected clones resembled that of control cells. However, secretion of triacylglycerol was markedly reduced in all the I-FABP-expressing cell lines. Our data suggest that increased expression of I-FABP leads to reduced triacylglycerol secretion in intestinal cells.
Gedde-Dahl
Ane
A
Department of Pharmacology, School of Pharmacy, University of Oslo, Norway. ane.gedde-dahl@haukeland.no
Kulseth
Mari Ann
MA
Ranheim
Trine
T
Drevon
Christian A
CA
Rustan
Arild C
AC
D018938:Caco-2 Cells; D002352:Carrier Proteins / Q000235:genetics* / Q000378:metabolism*; D004951:Esterification; D000071438:Fatty Acid-Binding Protein 7; D050556:Fatty Acid-Binding Proteins; D005227:Fatty Acids / Q000378:metabolism*; D015870:Gene Expression; D006801:Humans; D007413:Intestinal Mucosa / Q000378:metabolism; D009363:Neoplasm Proteins; D019301:Oleic Acid / Q000378:metabolism; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D014162:Transfection; D014280:Triglycerides / Q000378:metabolism*; D025521:Tumor Suppressor Proteins
D002352:Carrier Proteins; C107608:FABP7 protein, human; D000071438:Fatty Acid-Binding Protein 7; D050556:Fatty Acid-Binding Proteins; D005227:Fatty Acids; D009363:Neoplasm Proteins; D012333:RNA, Messenger; D014280:Triglycerides; D025521:Tumor Suppressor Proteins; D019301:Oleic Acid