Nutritional control of fatty acid esterification in differentiating Caco-2 intestinal cells is mediated by cellular diacylglycerol concentrations.
The Caco-2 human intestinal cell line was used to investigate the effects of exogenous lipid on fatty acid esterification in differentiating intestinal absorptive cells. Preincubation of Caco-2 cells with either palmitate or palmitate plus 2-monoolein resulted in greater utilization of subsequently added fatty acid for triacylglycerol relative to phosphatidylcholine synthesis. Despite this lipid-induced alteration in metabolism, the activities of acyl-CoA synthetase, glycerol-3-phosphate acyltransferase and diacylglycerol acyltransferase were unchanged. In addition, monoacylglycerol acyltransferase activity was nearly undetectable, even after preincubation with 2-monoolein. The intracellular diacylglycerol concentrations were, however, increased with greater lipid substrate availability. These studies indicate that, under conditions of increased dietary lipid, intestinal fatty acid esterification via the glycerol-3-phosphate pathway is modulated by cellular diacylglycerol concentrations.
Trotter
P J
PJ
Department of Nutrition, Harvard School of Public Health, Boston, MA.
Storch
J
J
D000217:Acyltransferases / Q000378:metabolism*; D002460:Cell Line; D002478:Cells, Cultured; D004075:Diglycerides / Q000378:metabolism / Q000494:pharmacology*; D004951:Esterification; D005227:Fatty Acids / Q000378:metabolism*; D006801:Humans; D007413:Intestinal Mucosa / Q000378:metabolism*; D007422:Intestines / Q000201:enzymology
D004075:Diglycerides; D005227:Fatty Acids; D000217:Acyltransferases