Journal or Book Title
Journal of Animal Science
The objective was to investigate the of effect chemical composition of dietary fat on transcription of genes involved in lipid metabolism in adipose tissue and liver via transcriptional profiling in growing pigs. A total of 48 Genetiporc 6.0 × Genetiporc F25 (PIC, Inc., Hendersonville, TN) barrows (initial BW of 44.1 ± 1.2 kg) were randomly allotted to 1 of 6 dietary treatments. Each experimental diet included 95% of a corn-soybean meal basal diet and 5% of either: corn starch (CNTR), animal-vegetable blend (AV), coconut oil (COCO), corn oil (COIL), fish oil (FO), or tallow (TAL). Pigs were sacrificed on d 10 (final BW of 51.2 ± 1.7 kg) to collect tissues. Expression normalization across samples was performed by calculating a delta Ct (ΔCt; cycle threshold) value using RPL32. Delta delta Ct values (ΔΔCt) were expressed relative to the CNTR treatment. In adipose tissue adding dietary fat regardless of source decreased the mRNA abundance of FASN compared to CNTR fed pigs (P = 0.014). Of the dietary fat sources tested, pigs fed a COIL based diet tended to have greater adipose tissue expression of FASN (P = 0.071). Abundance of PRKAG-1 mRNA was greater in adipose tissue of barrows a fed COIL based diet than barrows fed CNTR or FO diets (P = 0.047). In liver adding dietary fat regardless of source increased the mRNA abundance of ACACA, ATGL, INSR, PPAR-α, PRKAG-1, and SCD (P ≤ 0.020) and tended to have greater abundance of HSL (P = 0.071) and SREBP-1 (P = 0.086) compared to CNTR fed barrows. Pigs fed a TAL based diet had greater hepatic transcription of HSL than pigs fed CNTR, COCO, or FO diets (P = 0.013). Hepatic transcription of FASN tended to be greater in pigs fed COCO than pigs fed other dietary fat sources (P = 0.074). Dietary omega-3 fatty acid content tended to negatively correlate with mRNA abundance of PRKAG-1 (P = 0.065) in adipose tissue and ATGL (P = 0.063) in liver. Dietary fat SFA content was negatively correlated with PPAR-α in liver (P ≤ 0.039). Dietary fat MUFA content tended to be positively correlated with ACACA, PPAR-α, PRKAG-1 mRNA abundance in liver (P ≤ 0.100). To conclude, the intake of omega-3 fatty acids suppressed the mRNA abundance of genes involved in lipolysis in both adipose tissue and liver. Dietary SFAs are greater inhibitors of lipogenesis in adipose tissue than omega-6 fatty acids. Intake of medium chain fatty acids alter hepatic lipid metabolism differently than intake of long chain fatty acids.
American Society of Animal Science
Kellner, T. A.; Gabler, Nicholas K.; and Patience, John F., "The composition of dietary fat alters the transcriptional profile of pathways associated with lipid metabolism in the liver and adipose tissue in the pig" (2017). Animal Science Publications. 816.