Genes Related to Fat Metabolism in Pigs and Intramuscular Fat Content of Pork: A Focus on Nutrigenetics and Nutrigenomics

Abstract

Fat metabolism and intramuscular fat (IMF) are qualitative traits in pigs whose development are influenced by several genes and metabolic pathways. Nutrigenetics and nutrigenomics offer prospects in estimating nutrients required by a pig. Application of these emerging fields in nutritional science provides an opportunity for matching nutrients based on the genetic make-up of the pig for trait improvements. Today, integration of high throughput “omics” technologies into nutritional genomic research has revealed many quantitative trait loci (QTLs) and single nucleotide polymorphisms (SNPs) for the mutation(s) of key genes directly or indirectly involved in fat metabolism and IMF deposition in pigs. Nutrient–gene interaction and the underlying molecular mechanisms involved in fatty acid synthesis and marbling in pigs is difficult to unravel. While existing knowledge on QTLs and SNPs of genes related to fat metabolism and IMF development is yet to be harmonized, the scientific explanations behind the nature of the existing correlation between the nutrients, the genes and the environment remain unclear, being inconclusive or lacking precision. This paper aimed to: (1) discuss nutrigenetics, nutrigenomics and epigenetic mechanisms controlling fat metabolism and IMF accretion in pigs; (2) highlight the potentials of these concepts in pig nutritional programming and research.

Differential Gene Expression Associated with Soybean Oil Level in the Diet of Pigs

“…4 PUFA:SFA ratio = total PUFA/total SFA. 5 Σ n-6/Σ n-3 PUFA ratio. Pigs (n = 35) were fed either a corn-soybean meal diet containing 1.5% soybean oil (SOY1.5) or diet containing 3% soybean oil (SOY3.0).…”

“…These diseases have in common the influence of genetic factors, oxidative stress, and inflammation as result of sedentary lifestyle, diet, and consumption of drugs and alcohol. Pigs have been used as an animal model for diseases and in nutrigenetics and nutrigenomics [2][3][4][5].…”

“…Among its many benefits are its supply of unsaturated fatty acids, such as oleic acid (AO, C18:1 cis 9) and linoleic acid (AL, C18:2 cis9, 12), which have positive effects on human health [8]. Pigs have been increasingly used in nutrigenomics research and for the investigation of metabolic diseases in humans due to their role as an animal model for humans [2,5,9]. Pigs have similarities in terms of anatomy, biochemistry, pathology, pharmacology, and physiology with humans which causes them to be used as an animal model [3,[9][10][11].…”

Improvement of Intramuscular Fat in longissimus Muscle of Finishing Thai Crossbred Black Pigs by Perilla Cake Supplementation in a Low-Lysine Diet

“…In porcine muscle, a low-lysine diet increases the gene expression of glucose transporter protein 4 and peroxisome proliferator-activated receptor gamma (PPAR-γ), which is associated with increased mitochondrial oxidative enzyme activity [ 11 ]. The PPAR-γ gene plays a central role in the regulation of adipogenesis, a process by which fibroblast-like preadipocytes differentiate into mature adipocytes [ 38 , 39 ]. Moreover, the activity of mitochondrial oxidative enzymes is positively correlated with the amount of IMF in bovine muscles [ 11 , 40 ].…”

Integrative Analysis of Nanopore and Illumina Sequencing Reveals Alternative Splicing Complexity in Pig Longissimus Dorsi Muscle

“…Increased IMF content not only promotes the sensory attributes ( Alfaia et al, 2019 ), but also affects the flavor and shear force of pork ( Zhang et al, 2021 ). Furthermore, consumers are more likely to accept meat with higher IMF ( Malgwi et al, 2022 ). However, the molecular mechanism and transcriptional regulation process of IMF deposition are still unclear.…”