Regulation of apolipoprotein secretion by long-chain polyunsaturated fatty acids in newborn swine enterocytes.
Long-chain polyunsaturated fatty acids (LC-PUFA) are important in the development of the immature nervous system, and adding these fatty acids to infant formula has been proposed. To determine the effect of n-3 LC-PUFA on apolipoprotein secretion and lipid synthesis in newborn swine enterocytes, differentiated IPEC-1 cells were incubated for 24 h with docosahexaenoic acid (DHA; 22:6) or eicosapentaenoic acid (EPA; 20:5) complexed with albumin at a fatty acid concentration of 0.8 mM or albumin alone (control) added to the apical medium. Oleic acid (OA; 18:1) was used a control for lipid-labeling studies. Both DHA and EPA reduced apolipoprotein (apo) B secretion by one-half, whereas EPA increased apo A-I secretion. The increased apo A-I secretion occurred primarily in the high-density lipoprotein fraction. These changes in apoprotein secretion were not accompanied by significant changes in synthesis. Modest decreases in apo B mRNA levels were observed for DHA and EPA, whereas there were no changes in apo A-I mRNA abundance. EPA reduced cellular triacylglycerol labeling by one-half, and DHA and EPA decreased cellular phospholipid labeling compared with OA. Labeled triacylglycerol secretion was decreased 75% by EPA, and DHA doubled labeled phospholipid secretion. If present in vivo, these effects should be considered before supplementing infant formula with these fatty acids.
Wang
H
H
Arkansas Children's Hospital Research Institute, University of Arkansas for Medical Sciences, Little Rock, Arkansas 72202, USA.
Lu
S
S
Du
J
J
Yao
Y
Y
Berschneider
H M
HM
Black
D D
DD
D000818:Animals; D000831:Animals, Newborn / Q000502:physiology*; D001053:Apolipoproteins / Q000235:genetics / Q000378:metabolism*; D002460:Cell Line; D004281:Docosahexaenoic Acids / Q000494:pharmacology*; D015118:Eicosapentaenoic Acid / Q000494:pharmacology; D020895:Enterocytes / Q000187:drug effects* / Q000378:metabolism*; D010743:Phospholipids / Q000096:biosynthesis; D012333:RNA, Messenger / Q000378:metabolism; D013552:Swine; D014280:Triglycerides / Q000096:biosynthesis
D001053:Apolipoproteins; D010743:Phospholipids; D012333:RNA, Messenger; D014280:Triglycerides; D004281:Docosahexaenoic Acids; D015118:Eicosapentaenoic Acid