title: Impact of saturated, polyunsaturated and monounsaturated fatty acid-rich micelles on lipoprotein synthesis and secretion in Caco-2 cells.
abstract: Meal fatty acids have been shown to modulate the size and composition of triacylglycerol (TAG)-rich lipoproteins influencing the magnitude and duration of the postprandial plasma TAG response. As a result there is considerable interest in the origin of these meal fatty-acid induced differences in particle composition. Caco-2 cells were incubated over 4 days with fatty acid mixtures resembling the composition of saturated (SFA), monounsaturated (MUFA) and polyunsaturated fatty acid (PUFA)-rich meals fed in a previous postprandial study to determine their impact on lipoprotein synthesis and secretion. The MUFA- and PUFA-rich mixtures supported greater intracellular TAG, but not cholesterol accumulation compared with the SFA-rich mixture (P < 0.001). The MUFA-rich mixture promoted significantly greater TAG and cholesterol secretion than the other mixtures and significantly more apolipoprotein B-100 secretion than the PUFA-rich mixture (P < 0.05). Electron microscopy revealed the SFA-rich mixture had led to unfavourable effects on cellular morphology, compared with the unsaturated fatty acid-rich mixtures. Our findings suggest the MUFA-rich mixture, may support the formation of a greater number of TAG-rich lipoproteins, which is consistent with indirect observations from our human study. Our electron micrographs are suggestive that some endocytotic uptake of MUFA-rich taurocholate micelles may promote greater lipoprotein synthesis and secretion in Caco-2 cells.
authors.affiliation: Hugh Sinclair Unit of Human Nutrition, Department of Food and Nutritional Sciences, School of Chemistry, Food and Pharmacy, University of Reading, Reading, RG6 6AP, UK. k.g.jackson@reading.ac.uk
authors.forename: Kim G
authors.initials: KG
authors.lastname: Jackson
authors.forename: Paul A
authors.initials: PA
authors.lastname: Bateman
authors.forename: Parveen
authors.initials: P
authors.lastname: Yaqoob
authors.forename: Christine M
authors.initials: CM
authors.lastname: Williams
mesh_terms: D018938:Caco-2 Cells; D002477:Cells / Q000166:cytology / Q000187:drug effects; D005227:Fatty Acids / Q000494:pharmacology*; D005229:Fatty Acids, Monounsaturated / Q000494:pharmacology*; D005231:Fatty Acids, Unsaturated / Q000494:pharmacology*; D006801:Humans; D008074:Lipoproteins / Q000096:biosynthesis* / Q000378:metabolism; D008823:Micelles
chemical_list: D005227:Fatty Acids; D005229:Fatty Acids, Monounsaturated; D005231:Fatty Acids, Unsaturated; D008074:Lipoproteins; D008823:Micelles