title: Conjugated linoleic acid enhances transepithelial calcium transport in human intestinal-like Caco-2 cells: an insight into molecular changes.
abstract: Conjugated linoleic acid (CLA) has been shown to enhance paracellular and transcellular Ca transport across human intestinal-like Caco-2 cell monolayers. The mechanisms of action, however, are still unclear. Therefore, this study investigated the molecular mechanisms underlying CLA-induced stimulation of Ca transport by use of preliminary microarray data together with more detailed and comprehensive quantitative reverse transcriptase-PCR analysis. While molecular expression of junctional adhesion molecule (JAM), ZO-2, ZO-3, claudin 2 and claudin 3 were unaltered, ZO-1, occludin, and claudin 4 were all up-regulated (1.6, 1.6, 2.4-fold, respectively; P<0.001-0.01) and claudin 1 down-regulated (2.5-fold; P<0.05) by trans-10, cis-12 CLA, which may underpin its effects on tight-junction function and paracellular Ca transport. On the other hand, expression of key genes involved in transcellular Ca transport (CaT1, ECaC1, calbindin D(9k), vitamin D receptor and PMCA) were unaffected by trans-10, cis-12 CLA. The mechanism by which CLA enhances transcellular Ca transport remains unclear.
authors.affiliation: Department of Food and Nutritional Sciences, University College, Cork, Ireland.
authors.forename: Eileen F
authors.initials: EF
authors.lastname: Murphy
authors.forename: Christopher
authors.initials: C
authors.lastname: Jewell
authors.forename: Guido J
authors.initials: GJ
authors.lastname: Hooiveld
authors.forename: Michael
authors.initials: M
authors.lastname: Muller
authors.forename: Kevin D
authors.initials: KD
authors.lastname: Cashman
mesh_terms: D001692:Biological Transport / Q000187:drug effects; D018938:Caco-2 Cells; D002118:Calcium / Q000378:metabolism*; D015220:Calcium Channels / Q000378:metabolism; D002463:Cell Membrane Permeability / Q000187:drug effects; D062445:Claudin-1; D062506:Claudin-4; D015870:Gene Expression / Q000187:drug effects; D006801:Humans; D007413:Intestinal Mucosa / Q000166:cytology / Q000378:metabolism*; D044243:Linoleic Acids, Conjugated / Q000494:pharmacology*; D008565:Membrane Proteins / Q000235:genetics; D062793:Occludin; D020411:Oligonucleotide Array Sequence Analysis / Q000379:methods; D019108:Tight Junctions / Q000187:drug effects / Q000235:genetics / Q000378:metabolism
chemical_list: C568108:CLDN1 protein, human; C568157:CLDN4 protein, human; D015220:Calcium Channels; D062445:Claudin-1; D062506:Claudin-4; D044243:Linoleic Acids, Conjugated; D008565:Membrane Proteins; C568985:OCLN protein, human; D062793:Occludin; D002118:Calcium