140 ASAS-EAAP Exchange Speaker Talk: Effects of different sources of fat in the diet of pigs on the liver transcriptome estimated by 3`RNA-sequencing

Abstract

Abstract The effect of different fats [rapeseed oil (group I n = 6), beef tallow (group II n = 6), coconut oil (group III n = 5)] in the diet of pigs on the liver transcriptomic profile was analyzed using the 3`quant mRNA-sequencing method (Lexogen, Vienna, Austria). In this method the quantification of gene expression is based only on the 3 ‘UTR fragment of genes in contrast to traditional RNA-seq in which the analysis is based on the entire length of the transcripts. Thus, this method is much cheaper and some sources claim that it is also more sensitive. Using this method, we detected approximately 1000 Differentially Expressed genes (DEGs) between samples from the liver of individuals fed with the addition of rapeseed oil when compared to samples from animals receiving beef tallow in the diet (base mean >10, fold change >1.5, p-adjusted< 0.05). More than 700 DEGs and about 100 DEGs were identified in group I vs group III and group II vs group III comparisons respectively. Functional analysis with STRING software revealed 287, and 233 significant Biological Processes in group I vs group II and group I vs group III comparisons respectively. Among genes with altered expression, there were many genes playing a key role in signalling pathways, autophagy, mitophagy, complement and coagulation cascade, cholesterol metabolism, oxidative stress, RNA and protein processing. Significant part of these genes were strongly associated with human diseases: Non Alcoholic Fatty Liver Disease (NAFLD), cancer, Parkinson`s disease, Alzheimer`s disease and cardiovascular diseases. There were many overlapping genes and biological processes in results of comparisons of rapeseed oil group with beef tallow and coconut oil groups, however pathways connected to atherosclerosis and cardiovascular diseases were only observed in group I vs group II comparisons. These results are preliminary and will be validated by qPCR. Table 1. Top 20 DEGs identified in three comparisons.