Adipose tissue transcriptional response of lipid metabolism genes in growing Iberian pigs fed oleic acid v. carbohydrate enriched diets

Abstract

Diet influences animal body and tissue composition due to direct deposition and to the nutrients effects on metabolism. The influence of specific nutrients on the molecular regulation of lipogenesis is not well characterized and is known to be influenced by many factors including timing and physiological status. A trial was performed to study the effects of different dietary energy sources on lipogenic genes transcription in ham adipose tissue of Iberian pigs, at different growth periods and on feeding/fasting situations. A total of 27 Iberian male pigs of 28 kg BW were allocated to two separate groups and fed with different isocaloric feeding regimens: standard diet with carbohydrates as energy source (CH) or diet enriched with high oleic sunflower oil (HO). Ham subcutaneous adipose tissue was sampled by biopsy at growing (44 kg mean BW) and finishing (100 kg mean BW) periods. The first sampling was performed on fasted animals, while the last sampling was performed twice, with animals fasted overnight and 3 h after refeeding. Effects of diet, growth period and feeding/fasting status on gene expression were explored quantifying the expression of a panel of key genes implicated in lipogenesis and lipid metabolism processes. Quantitative PCR revealed several differentially expressed genes according to diet, with similar results at both timings: RXRG, LEP and FABP5 genes were upregulated in HO group while ME1, FASN, ACACA and ELOVL6 were upregulated in CH. The diet effect on ME1 gene expression was conditional on feeding/fasting status, with the higher ME1 gene expression in CH than HO groups, observed only in fasting samples. Results are compatible with a higher de novo endogenous synthesis of fatty acids (FA) in the carbohydrate-supplemented group and a higher FA transport in the oleic acid-supplemented group. Growth period significantly affected the expression of most of the studied genes, with all but PPARG showing higher expression in finishing pigs according to a pattern dissimilar from the usual in cosmopolitan pig breeds. Feeding/fasting status only influenced PPARG gene transcription. The lack of effects of feeding/ fasting status on lipogenic gene expression and the higher ME1 response to diet in fasting samples than in postprandial sampling, suggest the persistence of de novo lipogenesis during fasting. Overall results improve the understanding of the influence of different factors on lipid metabolism regulation in Iberian pigs.

Anti-Obesity Effect of Bombus ignitus Queen Glycosaminoglycans in Rats on a High-Fat Diet

“…Class 3 semaphorins (Sema3C) secrete guidance proteins [24] and Fasn, which are involved in the adipose tissue transcriptional response of lipid metabolism [25], were upregulated. Ugt2b, UDP glycosyltransferase 2 family, polypeptide B [26], and Igfbp1 (insulin-like growth factor binding protein 1) [27] were down-regulated.…”

Modulatory Effects of Breed, Feeding Status, and Diet on Adipogenic, Lipogenic, and Lipolytic Gene Expression in Growing Iberian and Duroc Pigs

“…Monounsaturated fatty acids (MUFA)-enriched diets with the inclusion of high oleic acid sunflower oil, are being used in Iberian pig intensive fattening systems in order to increase oleic acid and to be used as an alternative to the traditional fattening system of Montanera [ 7 , 8 ]. Recently, the impact of high oleic sunflower oil (HO)- versus carbohydrate (CH)-enriched diets on tissue composition and their short- and long-term effects on gene transcription have been evaluated in pure Iberian pigs [ 9 , 10 , 11 , 12 ]. In previous works, the effects of diet composition on gene expression were small and conditioned by several factors, such as timing and feeding status.…”

FeedOmics, an approach to evaluate the functional properties of protein containing feed ingredients

“…This suggests that only subtle effects on the intestinal mucosal gene expression are induced in pigs by diets containing protein from different sources. This is in agreement with a number of other transcriptomic studies on nutritional effects where extreme dietary manipulations were avoided (Oster et al, 2012;Óvilo et al, 2014;Benítez et al, 2016). However, differences in biological mechanisms cannot be explained by the activity of single genes alone, they are often attributed to groups of genes (Mootha et al, 2003) based on their annotation.…”