Functional characterization of three clones of the human intestinal Caco-2 cell line for dietary lipid processing

Abstract

We aimed to improve the use of the human intestinal Caco-2 cell line for studying dietary lipid and cholesterol processing by using isolated pure clones . Three clones (TC7, PD7 and PF11) were grown as monolayers on semi-permeable filters and compared for cell viability, fatty acid and cholesterol apical uptake or basolateral secretion, apolipoprotein B-48 basolateral secretion and 3-hydroxy-3-methylglutaryl (HMG)-CoA reductase activity. The TC7 clone showed the best viability upon apical incubation with mixed micelles and should be preferred for routine work. Short-term (3·0 h) rates of apical uptake of cholesterol were not different with the three clones, whereas the rate of apical uptake of oleic acid (18 : 1) was lower (P,0·05) with PF11 (250·6 nmol/mg) and the basolateral secretion of cholesterol and oleic acid was lower with the TC7 clone (0·40 and 29·1 nmol/mg respectively). The secretion of apolipoprotein B-48 basolaterally was about 2-fold lower than from PD7 clone. The basal levels of HMG-CoA reductase activity were significantly different (P,0·05; TC7.PF11.PD7). The down-regulation of the enzyme activity was moderate (range 13·8 -21·0 %) and comparable in the presence of apical micellar cholesterol, but was much marked upon basolateral incubation with LDL (range 34·0 -53·6 %), especially for the PD7 clone. In conclusion, the Caco-2 clones characterized here proved to be particularly suitable for studying lipid nutrients processing. Because these three clones exhibit some different metabolic capabilities, they provide a new tool to study intestinal response to lipid nutrients.Cholesterol: Lipids: Absorption: Intestine * Corresponding author: Dr Denis Lairon, fax +33 491 75 15 62, email lairon@marseille.inserm.fr Abbreviations: Apo, apolipoprotein; HMG, 3-hydroxy-3-methylglutaryl; LDH, lactate dehydrogenase.

Scavenger receptor class B type I reduces cholesterol absorption in cultured enterocyte CaCo-2 cells

“…Bile salt concentrations in the human small intestine average 14.5 mM (36). Therefore, we used concentrations that were significantly higher than those described in the literature, typically 5 mM (14,37,38), which does not exceed the critical micellar concentration of 4-6 mM (39) for this bile salt. The high bile salt concentration appeared not to affect cell viability, even after 24 h of incubation.…”

Effect of the main dietary antioxidants (carotenoids, γ-tocopherol, polyphenols, and vitamin C) on α-tocopherol absorption

“…Caco-2 clone TC7 cells (Salvini et al, 2002) were a gift from Dr M Rousset (U178 INSERM, Villejuif, France). Cells were cultured in the presence of DMEM supplemented with 20% heat-inactivated FBS, 1% nonessential amino acid and 1% antibiotics (complete medium), as described previously (Reboul et al, 2005a).…”

Intestinal Scavenger Receptors Are Involved in Vitamin K1 Absorption

“…Caco-2 Cell Culture-Caco-2 clone TC-7 cells (17,18) were cultured in the presence of DMEM supplemented with 20% heat-inactivated FBS, 1% non-essential amino acids, and 1% antibiotics (complete medium), as described previously (13,19). For each experiment, cells were seeded and grown on transwell plates for 21 days to obtain confluent and highly differentiated cell monolayers.…”