Open AccessOverexpression of apolipoprotein C ‐ III decreases secretion of dietary triglyceride into lymph
Author(s) -
Wang Fei,
Kohan Alison B.,
Dong H. Henry,
Yang Qing,
Xu Min,
Huesman Sarah,
Lou Danwen,
Hui David Y.,
Tso Patrick
Publication year - 2014
Publication title -
physiological reports
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.918
H-Index - 39
ISSN - 2051-817X
DOI - 10.1002/phy2.247
Subject(s) - chylomicron , monoacylglycerol lipase , medicine , apolipoprotein b , lymphatic system , endocrinology , triglyceride , small intestine , lymph , chemistry , lipoprotein , lipid metabolism , intestinal mucosa , biochemistry , biology , very low density lipoprotein , cholesterol , immunology , pathology , endocannabinoid system , receptor
Apolipoprotein C ‐ III (apo C ‐ III ) is not only predominantly synthesized by the liver but also by the small intestine. Because apo C ‐ III is secreted from the intestine on the chylomicron along with lipid absorption, we questioned whether apo C ‐ III might play a role in intestinal lipid absorption and/or transport. Using both wild‐type ( WT ) and apo C ‐ III transgenic (apo C ‐ III Tg) mice, we showed that apo C ‐ III Tg mice have decreased lymphatic lipid transport compared with WT mice in response to an intraduodenal infusion of radiolabeled lipid. This is associated with accumulation of radiolabeled lipids in the luminal compartment of the apo C ‐ III Tg mice, indicating delayed lipid uptake from the lumen. The total amount of radioactive lipids in the mucosal compartment did not differ between apo C ‐ III Tg and WT mice, but the lipid distribution analysis indicated a predominance of free fatty acids and monoacylglycerol in the mucosa of apo C ‐ III Tg mice, implying impaired esterification capacity. Thus, the mechanisms underlying the reduced lymphatic lipid transport in apo C ‐ III T g mice involve both a delayed lipid uptake into enterocytes, as well as impaired esterification to form triglyceride in the mucosa. These data document a novel role for apo C ‐ III in the uptake, re‐esterification, and lymphatic transport of dietary lipids in the intestine.