TY - JOUR
T1 - Oleoylethanolamide differentially regulates glycerolipid synthesis and lipoprotein secretion in intestine and liver
AU - Pan, Xiaoyue
AU - Schwartz, Gary J.
AU - Hussain, M. Mahmood
N1 - Publisher Copyright:
© 2018 American Society for Biochemistry and Molecular Biology Inc. All Rights Reserved.
PY - 2018
Y1 - 2018
N2 - Dietary fat absorption takes place in the intestine, and the liver mobilizes endogenous fat to other tissues by synthesizing lipoproteins that require apoB and microsomal triglyceride transfer protein (MTP). Dietary fat triggers the synthesis of oleoylethanolamide (OEA), a regulatory fatty acid that signals satiety to reduce food intake mainly by enhancing neural PPAR activity, in enterocytes. We explored OEA’s roles in the assembly of lipoproteins in WT and Ppara/ mouse enterocytes and hepatocytes, Caco-2 cells, and human liver-derived cells. In differentiated Caco-2 cells, OEA increased synthesis and secretion of triacylglycerols, apoB secretion in chylomicrons, and MTP expression in a dose-dependent manner. OEA also increased MTP activity and triacylglycerol secretion in WT and knockout primary enterocytes. In contrast to its intestinal cell effects, OEA reduced synthesis and secretion of triacylglycerols, apoB secretion, and MTP expression and activity in human hepatoma Huh-7 and HepG2 cells. Also, OEA reduced MTP expression and triacylglycerol secretion in WT, but not knockout, primary hepatocytes. These studies indicate differential effects of OEA on lipid synthesis and lipoprotein assembly: in enterocytes, OEA augments glycerolipid synthesis and lipoprotein assembly independent of PPAR. Conversely, in hepatocytes, OEA reduces MTP expression, glycerolipid synthesis, and lipoprotein secretion through PPAR-dependent mechanisms.
AB - Dietary fat absorption takes place in the intestine, and the liver mobilizes endogenous fat to other tissues by synthesizing lipoproteins that require apoB and microsomal triglyceride transfer protein (MTP). Dietary fat triggers the synthesis of oleoylethanolamide (OEA), a regulatory fatty acid that signals satiety to reduce food intake mainly by enhancing neural PPAR activity, in enterocytes. We explored OEA’s roles in the assembly of lipoproteins in WT and Ppara/ mouse enterocytes and hepatocytes, Caco-2 cells, and human liver-derived cells. In differentiated Caco-2 cells, OEA increased synthesis and secretion of triacylglycerols, apoB secretion in chylomicrons, and MTP expression in a dose-dependent manner. OEA also increased MTP activity and triacylglycerol secretion in WT and knockout primary enterocytes. In contrast to its intestinal cell effects, OEA reduced synthesis and secretion of triacylglycerols, apoB secretion, and MTP expression and activity in human hepatoma Huh-7 and HepG2 cells. Also, OEA reduced MTP expression and triacylglycerol secretion in WT, but not knockout, primary hepatocytes. These studies indicate differential effects of OEA on lipid synthesis and lipoprotein assembly: in enterocytes, OEA augments glycerolipid synthesis and lipoprotein assembly independent of PPAR. Conversely, in hepatocytes, OEA reduces MTP expression, glycerolipid synthesis, and lipoprotein secretion through PPAR-dependent mechanisms.
KW - Apolipoprotein B
KW - Chylomicrons
KW - Microsomal triglyceride transfer protein
KW - Oleic acid
KW - Peroxisome proliferator-activated receptor alpha
KW - Very low density lipoprotein
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U2 - 10.1194/jlr.M089250
DO - 10.1194/jlr.M089250
M3 - Article
C2 - 30369486
AN - SCOPUS:85057573378
SN - 0022-2275
VL - 59
SP - 2349
EP - 2359
JO - Journal of Lipid Research
JF - Journal of Lipid Research
IS - 12
ER -