Adipose tissue possesses the remarkable capacity to control its size and function in response to a variety of internal and external cues, such as nutritional status and temperature. The traditional view of adipose tissue as a passive reservoir for energy storage is no longer valid. Chapter 10 adipose tissue and lipid metabolism request pdf. Fat signals lipases and lipolysis in lipid metabolism and. Amyloid precursor protein contributes to the pathogenesis of alzheimers disease. Increased fat in diet, increased uptake of fats by liver if this exceeds the capacity of thr liver to synthesis vldl fatty liver. Consistent with lipase activities, g0s2 expression is. Adipose tissue plays a central role in regulating wholebody energy and glucose homeostasis through its subtle functions at both organ and systemic levels. In addition to adipocytes, adipose tissue contains the stromal vascular fraction svf of cells including preadipocytes, fibroblasts, vascular endothelial cells and a variety of immune cells such as adipose tissue macrophages. Introduction adipose tissue, which is primarily composed of adipocytes as well as preadipocytes, macrophages, endothelial cells, fibroblasts, and leucocytes, has been increasingly.
Some of the hormones produced by adipose cells influence sex hormone metabolism, blood pressure regulation, insulin sensitivity, fat storage and use, blood clotting, and cell signaling. Adipose tissue, connective tissue consisting mainly of fat cells adipose cells, or adipocytes, specialized to synthesize and contain large globules of fat, within a structural network of fibres. Adipose tissue acts as an endocrine system organ by generating hormones that influence metabolic activity in other organ systems. Adipose tissue and lipid metabolism department of biochemistry. One of the insights that has changed our appreciation of the role of adipocytes so dramatically over recent years has been the discovery of their hormonal role in the regulation of metabolism, energy intake, and fat storage. Young persimmon fruit extract suppresses obesity by. This chapter focuses on the biochemistry of lipid metabolism in the adipocyte. It is found mainly under the skin but also in deposits between the muscles, in the intestines and in. Adipose tissue and cholesterol metabolism the journal of lipid. Treatment of adipocytes with cholesterol during the adipocyte differentiation experiment, cholesterol 1 and 10 mm was added during adipocyte differentiation at.
The expression levels of genes involved with energy metabolism in adipose tissue. Rodents, guinea pigs, rabbits, pigs, as well as humans, have all been evaluated for the development of white adipose tissue. A total of 27 iberian male pigs of 28kg bw were allocated to two separate groups and fed with different isocaloric. Some evidences indicate that adipocytes, as the major cellular component of white adipose tissue, contribute to hepatic cholesterol metabolism via adipocytokines aldaghri et al.
A rise in some fatty acids see text for details can increase adipocyte glut4 mediated glucose uptake. Defining the human adipose tissue proteome to reveal. Lipogenesis is a process by which carbohydrate is converted into fatty acids, and promotes the biosynthesis of tg and expansion of lipid droplet in adipocytes. Adipose tissue as an endocrine organ the journal of. Responses of adipose tissue lipoprotein lipase to weight. Disorders in the synthesis of adipokines and cytokines that occur in obesity lead to changes in lipid and carbohydrates metabolism and, as a consequence, may lead to insulin resistance. Mcp1 plays a key role in attracting macrophage infiltration into adipose tissue, resulting in increased adipose tissue inflammation in obesity 35, 36. Obesity, bioactive lipids, and adipose tissue inflammation. Types and regularities of the distribution of fat tissue according to the location and characteristics of the metabolism of adipose tissue are divided into three main types. Lipidladen macrophages are believed to play a key role in obesityinduced adipose tissue inflammation. Fatty liver due to increased plasma ffa in starvation, uncontrolled dm there is excess lipolysis from adipose tissue leading to increased plasma ffa. Adipose tissue was at first characterized as a connective tissue that contained lipid droplets, without a link to the metabolism of the organism.
Adipose tissue is currently known to secrete a large number of proteins termed adipokines that act in an autocrine. Tshb mrna is linked to cholesterol metabolism in adipose. Dysregulation of amyloid precursor protein impairs adipose. With an endocrine repertoire both responsive to systemic changes and communicating with many peripheral organs, as well as with satiety centers in the brain, adipose tissue is now recognized as the central hub of energy homeostasis. Cholesterol is an extremely important biological molecule that has roles in membrane structure as well as being a precursor for the synthesis of the steroid hormones, the bile acids, and vitamin d. The time when adipose tissue was regarded as mere passive fat storage and cushion is long gone. Supplementary key words lipoproteins hypolipidemic drugs poly. Young persimmon fruit ypf has recently been reported to have a regulatory effect on lipid metabolism. The protein is found in many tissues, with highest concentrations in adipose tissue and liver. Development of white and brown adipose tissue in vivo. Request pdf adipose tissue and lipid metabolism adipose tissue is the most variable carcass component and has traditionally been considered a rather.
Statins reduce epicardial adipose tissue attenuation. Tshb mrna is linked to cholesterol metabolism in adipose tissue. Although our study cannot determine whether the weight lossinduced changes in adipose tissue biological pathways contributed to the improvement observed in multiorgan insulin sensitivity, our data support the mechanistic links between wholebody metabolic function and adipose tissue cholesterol transport, ecm formation, and oxidative stress. A major function of adipose cells is to increase the. Subclinical hypothyroidism is known to be associated with increased serum cholesterol. In addition, higher visceral adipose tissue attenuation and pericoronary artery adipose tissue attenuation have been associated with an increased risk of all.
This study determines whether changes in abdominal abd and gluteal glt adipose tissue lipoprotein lipase lpl activity in response to a 6mo weight loss intervention, comprised of a hypocaloric diet and lowintensity walking, affect changes in body composition, fat distribution, lipid metabolism, and the magnitude of weight regain in 36 obese postmenopausal women. The adipose tissue is a central metabolic organ in the regulation of wholebody energy homeostasis. Metabolic complications affecting adipose tissue, lipid and glucose metabolism associated with hiv antiretroviral treatment. To study the effect of increased fatty acid oxidation in adipose tissue on the expression levels of genes related to obesity and diabetes, we isolated rna from the white adipose tissue of acc2mutant and wt mice fed either normal chow or a hfhc diet.
Brown adipose tissue activation is linked to distinct. Hilpda uncouples lipid droplet accumulation in adipose. After the discovery of adiposederived serum factors, adipose tissue is now regarded as an endocrine organ at the center of energy homeostasis. In the very beginning, the first session, we are going to have an overview of adipose tissue. The predominant lipolytic action of leptin may be mediated through the peripheral nervous system. Specific metabolic processes regulated by adipose tissue include lipid metabolism, glucose homeostasis, inflammation, angiogenesis, hemostasis regulation of blood coagulation, and blood pressure. The subsequent identification and characterization of leptin in. Adipocytes make up approximately onehalf of the cells in adipose tissue, the remainder being blood and endothelial cells, adipose precursor cells of varying degrees of. Lipolysis, lipophagy, cardiometabolic disease, obesity, adipose tissue, insulin resistance, type 2 diabetes, lipid metabolism.
For this reason, it is important to understand factors that control both the development and the composition of beef adipose tissues, and especially marbling adipose tissue, as it. Adipose tissue in man is a major site for cholesterol storage. Learn vocabulary, terms, and more with flashcards, games, and other study tools. The study of white adipose tissue wat development in mammals has been facilitated by the use of experimental animal models. Abnormal mitochondrial function in human white adipose tissue likely contributes to the secretion of lipid metabolites and lactate, which are linked to insulin resistance in peripheral tissues. This chapter describes the lipid metabolism in adipose tissue and focuses on the biochemistry of the adipocyte. Adipose tissue, when carried around in excessive amounts, predisposes to a large number of diseases. Polydatin inhibits adipose tissue inflammation and. Adipose tissue regulates hepatic cholesterol metabolism.
In addition it is known that adrenaline influences lipid metabolism in other tissues, inhib iting fatty acid synthesis in liver slices 7. Lipid metabolismadipose tissue metabolism authorstream presentation. Epidemiological data show that the prevalence of obesity has significantly increased over the past 20 years and continues to do so at an alarming rate. Adipose tissue compartments in lower body, upper body subcutaneous and visceral regions apparently differ in their actions on fatty acid metabolism and on their associations with meta. The human proteome in adipose tissue the human protein atlas. Obesity and the role of adipose tissue in inflammation and. However, the relevance of adipose tissue energy metabolism for the regulation of human insulin sensitivity remains to be further elucidated. Fasting and leptin independently increase adipose tissue lipolysis, while fasting decreases leptinsecretion. Dietary cholesterol effects on adipose tissue inflammation ncbi. In order to clarify its pathophysiological role, we investigated the significance of pdgf receptor. Energy metabolism of white adipose tissue and insulin. Testosterone differentially regulates targets of lipid and. Adipose tissue regulates hepatic cholesterol metabolism via adiponectin article in life sciences 1181 october 2014 with reads how we measure reads. Adipose tissue metabolism in acquired obesity sini heinonen academic dissertation to be publicly discussed, with the permission of the medical faculty of the university of helsinki in lecture hall 1, haartman institute, haartmaninkatu 3, on november 25th 2016, at 12 oclock noon helsinki, finland 2016.
Fat metabolism, so among the four major macromolecules, like carbohydrates, protein, cholanic acid, and finally, fat, i mean, lipids. Marbling management of cattle to maximize the deposition. Most of the fat in chickens is located in adipose depots, which are all late maturing. Lipid metabolismadipose tissue metabolism authorstream. Studies on the metabolism of adipose tissue journal of biological. Adipose tissue is the most variable carcass component and has traditionally been considered a rather inert storage tissue for energy in the form of lipids. The major form of adipose tissue in mammals commonly referred to as fat is white adipose tissue, wat. The white adipose tissue functions as a key energy reservoir for other organs, whereas the brown adipose tissue accumulates lipids for coldinduced adaptive thermogenesis. Plateletderived growth factor pdgf is a key factor in angiogenesis. Lipid metabolism and mobilization controlled by adipose tissue. Lipolysis, in an opposite way, breaks down tg to free fatty acid ffa.
As was the case with propionate1c 14, table ii shows that propionate 2c4 was converted to fatty acids by adipose tissue to a much greater extent than by liver. Adipocytes make up approximately one half of the cells in adipose tissue, the. Adipose tissue synthesizes and secretes numerous bioactive molecules, namely adipokines and cytokines, which affect the metabolism of both lipids and glucose. Metabolism and secretory function of white adipose tissue scielo. Cell metabolism short article brown adipose tissue activation is linked to distinct systemic effects on lipid metabolism in humans maria chondronikola,1,2,3,4 elena volpi,3,5,6,7 elisabet borsheim,1,8 craig porter,1,8 manish k. Since thyroidstimulating hormone tsh exerts an inductor effect on cholesterol biosynthesis, we aimed to investigate the relationship between tsh mrna and cholesterol metabolism in human adipose tissue at. Regulation of adipose tissue metabolism as a potential treatment for heart failure. As early as 1987, adipose tissue was identified as a major site for metabolism of sex steroids and production of adipsin, an endocrine factor that is markedly downregulated in rodent obesity. Recent advances have demonstrated that the adipocyte is not a passive lipid storage depot but a dynamic cell that plays a fundamental role in energy balance and.
Recent findings cold exposure triggers systemic changes in lipid metabolism, which increases fatty acid delivery to brown adipose tissue bat by various routes. Adipose tissue and lipid metabolism request pdf researchgate. These data showed that adipose tissue is a potential physiologic target of hepatic cholesterol metabolism. The aim of this study was to investigate whether the ypf aqueous extract ypfe exert an antiobesity effect by modulating lipid metabolism in the white adipose tissue wat of obese c57blksj dbdb mice. Metabolic complications affecting adipose tissue, lipid. In particular, in the context of bioenergetics, fat metabolism is very, very important, like carbohydrate metabolism. Lipogenesis is a process by which carbohydrate is converted into fatty acids, and promotes the. Adipose tissue, body fat, or simply fat is a loose connective tissue composed mostly of adipocytes. Glucose and fat metabolism in adipose tissue of acetylcoa. On one hand, adipose tissue stores energy in the form of lipid and controls the lipid mobilization and distribution in. Chapter 10 adipose tissue and lipid metabolism sciencedirect.
99 327 929 232 129 563 126 354 1325 1352 1177 699 576 997 367 1177 1126 428 1070 339 83 635 1316 1077 169 357 709 641 799 236 1255 1120 520 123 884 648 309 289 1238 395 468