title: Human colon cell culture models of different transformation stages to assess conjugated linoleic acid and conjugated linolenic acid metabolism: Challenges and chances.
abstract: Both cellular transformation status and cell culture conditions affect fatty acid metabolism. Hence, the incorporation and metabolism of c9,t11-CLA (conjugated linoleic acid) and other CFAs (conjugated fatty acids) were compared in colon cells (LT-97, adenoma; HT-29, adenocarcinoma). Growth inhibition by CFA in LT-97 cells was assessed via the DAPI (4',6-diamidino-2-phenylindole dihydrochloride) assay. Basal gene expression of desaturases (Δ5, Δ6 and Δ9) and elongases (1, 2, 5 and 6) was determined in LT-97 using PCR. Analysis of cellular fatty acids revealed a 2-fold higher incorporation of c9,t11-CLA (40 and 80μM) in HT-29 cells compared to LT-97 cells. The β-oxidized and elongated conjugated dienoic (CD) fatty acids differed by 8-fold (CD-C16:2/CD-C20:2; HT-29: 8:1; LT-97: 1:1). Notably, LT-97 cells were shown to convert conjugated linolenic acid (CLnA) to CLA. Moreover, LT-97 cells revealed no basal expression of elongase 2. CLnA caused stronger growth inhibition (≤80μM) compared to CLA (200μM). The results indicate that LT-97 cells represent a superior model to carry out elongation and desaturation studies of unsaturated and conjugated fatty acids compared to HT-29 cells. Nevertheless, further in-depth metabolic and transcriptomic analyses are required to confirm this suggestion.
authors.affiliation: Department of Nutritional Physiology, Institute of Nutrition, Friedrich-Schiller-University Jena, Dornburger Str. 24, 07743 Jena, Germany. b0dech@uni-jena.de
authors.forename: Christian
authors.initials: C
authors.lastname: Degen
authors.forename: Nina
authors.initials: N
authors.lastname: Habermann
authors.forename: Stefanie
authors.initials: S
authors.lastname: Piegholdt
authors.forename: Michael
authors.initials: M
authors.lastname: Glei
authors.forename: Gerhard
authors.initials: G
authors.lastname: Jahreis
mesh_terms: D045744:Cell Line, Tumor; D003110:Colonic Neoplasms / Q000378:metabolism; D005227:Fatty Acids / Q000737:chemistry / Q000378:metabolism / Q000494:pharmacology*; D019073:HT29 Cells; D006801:Humans; D007536:Isomerism
chemical_list: D005227:Fatty Acids