Regulation of lipid deposition in farm animals: Parallels between agriculture and human physiology

Abstract

For many years, clinically oriented scientists and animal scientists have focused on lipid metabolism and fat deposition in various fat depots. While dealing with a common biology across species, the goals of biomedical and food animals lipid metabolism research differ in emphasis. In humans, mechanisms and regulation of fat synthesis, accumulation of fat in regional fat depots, lipid metabolism and dysmetabolism in adipose, liver and cardiac tissues have been investigated. Further, energy balance and weight control have also been extensively explored in humans. Finally, obesity and associated maladies including high cholesterol and atherosclerosis, cardiovascular disease, insulin resistance, hypertension, metabolic syndrome and health outcomes have been widely studied. In food animals, the emphasis has been on regulation of fatty acid synthesis and lipid deposition in fat depots and deposition of intramuscular fat. For humans, understanding the regulation of energy balance and body weight and of prevention or treatment of obesity and associated maladies have been important clinical outcomes. In production of food animals lowering fat content in muscle foods while enhancing intramuscular fat (marbling) have been major targets. In this review, we summarize how our laboratories have addressed the goal of providing lean but yet tasty and juicy muscle food products to consumers. In addition, we here describe efforts in the development of a new porcine model to study regulation of fat metabolism and obesity. Commonalities and differences in regulation of lipid metabolism between humans, rodents and food animals are emphasized throughout this review.

Plasma lipidomic analysis reveals strong similarities between lipid fingerprints in human, hamster and mouse compared to other animal species

“…We confirmed that human and pig lipoprotein profiles were similar and characterized by elevated LDL cholesterol compared to HDL cholesterol levels 13 . This is likely related to the physiological and anatomical similarities between both species 14 . With regard to rats and hamsters, similar lipoprotein profile analysis showed comparable distribution of cholesterol within HDL and LDL.…”

Liver organoids in domestic animals: an expected promise for metabolic studies

“…To highlight the interest of developing the hepatic organoid model in these species, it is also necessary to identify the similarities and the differences and therefore to compare the hepatic metabolisms between the different species, including humans. If the metabolic pathways are generally very close, the nutritional lever is also used in domestic animals, in particular to control carbohydrate metabolism and lipidogenesis which does not take place exclusively in the liver for mammals with fat deposits in peripheral tissues [ 41 , 42 ].…”

“…Another example is the production of hepatic organoids from tissue biopsies in cats, to propose a model for studying NASH [ 46 ]. As previously mentioned, modeling this disease is still a challenge [ 36 ] and even if numerous rodent models are developed as well as in vivo assays on minipigs, few in vitro assays with organoids of mammalian domestic animals were presently reported [ 42 , 47 , 48 ].…”

“…In avian species, the importance of lipid metabolism in the body composition, nutritional egg quality, and adaptation of birds to environmental changes such as feed composition changes [ 51 – 53 ], or during steatosis processes, render the liver an important tissue to be studied, as it is the major organ in lipid synthesis in contrast to mammals [ 41 , 42 ]. As an example and as stated by Surugihalli et al, “the chicken liver is subjected to intense lipid burden from high rates of yolk-lipid oxidation and also from the accumulation of the yolk-derived and newly synthesized lipids from carbohydrates”.…”

Gene Expression Analysis Provides New Insights into the Mechanism of Intramuscular Fat Formation in Japanese Black Cattle

“…However, unlike cattle, humans accumulate intramuscular fat due to senescence and illness. Therefore, the marbling traits of Japanese Black cattle are considered a valuable research model for elucidating the molecular mechanism of ectopic intramuscular fat formation in various livestock, as well as in humans [5].…”