Submitted on April 30, 2007
Accepted on May 7, 2007
Development of Intestinal Lipid Absorption: Cellular Events in Chylomicron Assembly and Secretion
Dennis Darrel Black1*
1 Pediatrics, University of Tennessee Health Science Center, Memphis, Tennessee, United States
* To whom correspondence should be addressed. E-mail: dblack{at}utmem.edu.
The newborn mammal must efficiently absorb dietary fat, predominantly as triacylglycerol (TG), and produce chylomicrons to deliver this lipid to peripheral tissues. The cellular mechanisms involved in enterocyte chylomicron assembly have recently been elucidated, and data on their regulation in the immature gut are beginning to emerge. This review focuses on key proteins involved in chylomicron assembly, apo B-48, microsomal triglyceride transfer protein (MTP), and apo A-IV. Recent studies support a role for apo A-IV in enhancing chylomicron secretion by promoting production of larger particles. These proteins are regulated in a manner to maximize the lipid absorptive capacity of the newborn intestine.
