Coupling in vitro gastrointestinal lipolysis and Caco-2 cell cultures for testing the absorption of different food emulsions

Food Funct. 2012 May;3(5):537-46. doi: 10.1039/c2fo10248j. Epub 2012 Feb 21.

Abstract

There is a growing interest in the optimization of dietary emulsions for monitoring postprandial lipid metabolism in the frame of preventing metabolic diseases. Using various emulsions, we investigated in a systematic scheme the combination of (i) in vitro gastrointestinal lipolysis and (ii) absorption and metabolism of lipolysis media in Caco-2 cells. Four emulsions based on either milk fat olein (OL) or rapeseed oil (RA) as the dispersed phase and either lecithin (LE) or sodium caseinate (CA) as the emulsifier were tested. After a sequential incubation of these emulsions with gastric and pancreatic enzymes, lipolysis media were incubated with Caco-2 cells, after dilution (1 : 20) to maintain the barrier integrity. Both gastric and duodenal lipolysis levels were similar to values reported in vivo and the rates of lipolysis were higher with LE-stabilized emulsions than with CA-stabilized emulsions (P < 0.05). TAG secretion by Caco-2 cells was found to be higher using (i) duodenal vs. gastric media (P < 0.001) and (ii) emulsions stabilized with CA vs. LE (P < 0.01). Consistently, gene expression of both FABP2 and FATP4 induced by the duodenal media was (i) higher than that with gastric media (P < 0.001) and (ii) faster than that with model mixed micelles. Using gastric media, TAG secretion of Caco-2 cells after 12 h was higher with RA than with OL (P < 0.001). Moreover, the RA-CA emulsion increased the size of secreted lipoprotein particles (514 nm vs. 61 to 130 nm; P < 0.01). In conclusion, it was possible to observe distinct responses in the lipid metabolism of Caco-2 cells incubated with lipolysis media obtained from different dietary emulsions digested by gastrointestinal lipases in vitro.

Publication types

  • Comparative Study
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Caco-2 Cells
  • Chylomicrons / metabolism
  • Dietary Fats / analysis
  • Dietary Fats / metabolism*
  • Emulsifying Agents / chemistry
  • Emulsifying Agents / metabolism
  • Emulsions
  • Enterocytes / metabolism*
  • Fatty Acid Transport Proteins / genetics
  • Fatty Acid Transport Proteins / metabolism
  • Fatty Acid-Binding Proteins / genetics
  • Fatty Acid-Binding Proteins / metabolism
  • Feasibility Studies
  • Food Technology*
  • Gastric Juice / chemistry
  • Gastric Juice / enzymology
  • Gastric Juice / metabolism*
  • Gene Expression Regulation
  • Humans
  • Intestinal Absorption*
  • Kinetics
  • Lipolysis*
  • Models, Biological
  • Pancreatic Juice / chemistry
  • Pancreatic Juice / enzymology
  • Pancreatic Juice / metabolism*
  • Particle Size
  • RNA, Messenger / metabolism

Substances

  • Chylomicrons
  • Dietary Fats
  • Emulsifying Agents
  • Emulsions
  • FABP2 protein, human
  • Fatty Acid Transport Proteins
  • Fatty Acid-Binding Proteins
  • RNA, Messenger
  • SLC27A4 protein, human