Effects of trans fatty acids on markers of inflammation

Abstract

Trans fatty acids (tFA) contribute to inflammation. The objective of this study was to investigate the effects of tFA on mRNA expression of pro‐inflammatory markers. Bovine mammary epithelial cells (MACT) were grown in DMEM containing 10% FBS. Cells were then subcultured in a medium void of FBS, to which incremental concentrations (up to 90 μM) of tFA: BSA (FA‐free) solution were added and cells were collected at specific time‐points over 48 h. RNA was extracted and converted to cDNA for quantitative real time PCR analysis of pro‐inflammatory genes. Presence of elaidic acid (trans 9 C18:1) caused increases in mRNA expression of IL‐1β (3.4‐fold; dose‐independently over 6 h period) and ICAM‐1 (up to 1.4‐fold, dose× time P=0.0003), relative to that for cells treated with no tFA whereas expression of IL‐6 and IL‐8 was reduced. Presence of linoleidic acid (trans 9, trans 12 C18:2) tended to increase mRNA expression of ICAM‐1 by 1.5‐fold and increased that of IL‐1 β (up to 4‐fold; dose× time P=0.003) but reduced mRNA expression of IL‐6 and IL‐8, relative to that for control (no tFA). Trans mono‐ and dienoic FA up‐regulated mRNA expression of IL‐1β and ICAM‐1 while down‐regulated expression of IL‐6 and IL‐8 in bovine mammary epithelial cells. Reducing dietary tFA in lactating cattle rations or tFA formation in the rumen during biohydrogenation may lower the risk for mammary gland inflammation. Supported by NIH‐NRRI grant P20 RR15587.