scholarly journals Physiological role of adipose tissue: white adipose tissue as an endocrine and secretory organ

2001 ◽  
Vol 60 (3) ◽  
pp. 329-339 ◽  
Author(s):  
Paul Trayhurn ◽  
John H. Beattie
Keyword(s):  
Adipose Tissue ◽  
White Adipose Tissue ◽  
Physiological Role ◽  
Retinol Binding Protein ◽  
Endocrine Function ◽  
Specific Factor ◽  
Secretory Proteins ◽  
Metabolic Role ◽  
White Fat

The traditional role attributed to white adipose tissue is energy storage, fatty acids being released when fuel is required. The metabolic role of white fat is, however, complex. For example, the tissue is needed for normal glucose homeostasis and a role in inflammatory processes has been proposed. A radical change in perspective followed the discovery of leptin; this critical hormone in energy balance is produced principally by white fat, giving the tissue an endocrine function. Leptin is one of a number of proteins secreted from white adipocytes, which include angiotensinogen, adipsin, acylation-stimulating protein, adiponectin, retinol-binding protein, tumour neorosis factor a, interleukin 6, plasminogen activator inhibitor-1 and tissue factor. Some of these proteins are inflammatory cytokines, some play a role in lipid metabolism, while others are involved in vascular haemostasis or the complement system. The effects of specific proteins may be autocrine or paracrine, or the site of action may be distant from adipose tissue. The most recently described adipocyte secretory proteins are fasting-induced adipose factor, a fibrinogen–angiopoietin-related protein, metallothionein and resistin. Resistin is an adipose tissue-specific factor which is reported to induce insulin resistance, linking diabetes to obesity. Metallothionein is a metal-binding and stress-response protein which may have an antioxidant role. The key challenges in establishing the secretory functions of white fat are to identify the complement of secreted proteins, to establish the role of each secreted protein, and to assess the pathophysiological consequences of changes in adipocyte protein production with alterations in adiposity (obesity, fasting, cachexia). There is already considerable evidence of links between increased production of some adipocyte factors and the metabolic and cardiovascular complications of obesity. In essence, white adipose tissue is a major secretory and endocrine organ involved in a range of functions beyond simple fat storage.

Adipokines: inflammation and the pleiotropic role of white adipose tissue

2022 ◽  
Vol 127 (2) ◽  
pp. 161-164
Author(s):  
Paul Trayhurn
Keyword(s):  
Adipose Tissue ◽  
White Adipose Tissue ◽  
Physiological Role ◽  
Storage Organ ◽  
Multiple Functions ◽  
White Adipocytes ◽  
Brown Adipose ◽  
Simple Lipid ◽  
White Fat

I had been working on the endocrine and signalling role of white adipose tissue (WAT) since 1994 following the identification of the ob (Lep) gene(1), this after some 15 years investigating the physiological role of brown adipose tissue. The ob gene, a mutation in which it is responsible for the profound obesity of ob/ob (Lepob/Lepob) mice, is expressed primarily in white adipocytes and encodes the pleiotropic hormone leptin. The discovery of this adipocyte hormone had wide-ranging implications, including that white fat has multiple functions that far transcend the traditional picture of a simple lipid storage organ.

scholarly journals Adipokines: inflammation and the pleiotropic role of white adipose tissue

2004 ◽  
Vol 92 (3) ◽  
pp. 347-355 ◽  
Author(s):  
Paul Trayhurn ◽  
I. Stuart Wood
Keyword(s):  
Adipose Tissue ◽  
Growth Factor ◽  
Inflammatory Cytokines ◽  
Acute Phase ◽  
White Adipose Tissue ◽  
Acute Phase Proteins ◽  
Endocrine Function ◽  
Low Grade ◽  
Circulating Levels

White adipose tissue is now recognised to be a multifunctional organ; in addition to the central role of lipid storage, it has a major endocrine function secreting several hormones, notably leptin and adiponectin, and a diverse range of other protein factors. These various protein signals have been given the collective name ‘adipocytokines’ or ‘adipokines’. However, since most are neither ‘cytokines’ nor ‘cytokine-like’, it is recommended that the term ‘adipokine’ be universally adopted to describe a protein that is secreted from (and synthesised by) adipocytes. It is suggested that the term is restricted to proteins secreted from adipocytes, excluding signals released only by the other cell types (such as macrophages) in adipose tissue. Theadipokinome(which together with lipid moieties released, such as fatty acids and prostaglandins, constitute thesecretomeof fat cells) includes proteins involved in lipid metabolism, insulin sensitivity, the alternative complement system, vascular haemostasis, blood pressure regulation and angiogenesis, as well as the regulation of energy balance. In addition, there is a growing list of adipokines involved in inflammation (TNFα, IL-1β, IL-6, IL-8, IL-10, transforming growth factor-β, nerve growth factor) and the acute-phase response (plasminogen activator inhibitor-1, haptoglobin, serum amyloid A). Production of these proteins by adipose tissue is increased in obesity, and raised circulating levels of several acute-phase proteins and inflammatory cytokines has led to the view that the obese are characterised by a state of chronic low-grade inflammation, and that this links causally to insulin resistance and the metabolic syndrome. It is, however, unclear as to the extent to which adipose tissue contributes quantitatively to the elevated circulating levels of these factors in obesity and whether there is a generalised or local state of inflammation. The parsimonious view is that the increased production of inflammatory cytokines and acute-phase proteins by adipose tissue in obesity relates primarily to localised events within the expanding fat depots. It is suggested that these events reflect hypoxia in parts of the growing adipose tissue mass in advance of angiogenesis, and involve the key controller of the cellular response to hypoxia, the transcription factor hypoxia inducible factor-1.

Physiological regulation and metabolic role of browning in white adipose tissue

2017 ◽  
Vol 31 (1) ◽  
Author(s):  
Aleksandra Jankovic ◽  
Vesna Otasevic ◽  
Ana Stancic ◽  
Biljana Buzadzic ◽  
Aleksandra Korac ◽  
...  
Keyword(s):  
Adipose Tissue ◽  
White Adipose Tissue ◽  
Diabetes Type 2 ◽  
Cellular Mechanisms ◽  
Physiological Regulation ◽  
Metabolic Role ◽  
Brown Adipose ◽  
Beige Adipose Tissue

AbstractGreat progress has been made in our understanding of the browning process in white adipose tissue (WAT) in rodents. The recognition that i) adult humans have physiologically inducible brown adipose tissue (BAT) that may facilitate resistance to obesity and ii) that adult human BAT molecularly and functionally resembles beige adipose tissue in rodents, reignited optimism that obesity and obesity-related diabetes type 2 can be battled by controlling the browning of WAT. In this review the main cellular mechanisms and molecular mediators of browning of WAT in different physiological states are summarized. The relevance of browning of WAT in metabolic health is considered primarily through a modulation of biological role of fat tissue in overall metabolic homeostasis.

scholarly journals ENDOCRINE FUNCTION OF ADIPOSE TISSUE (LITERATURE REVIEW)

2021 ◽  
Vol 28 (2) ◽  
pp. 18-25
Author(s):  
Vladimir Georgievich Solovyov ◽  
◽  
Svetlana Petrovna Kalashnikova ◽  
Lyubov Gennadievna Nikonova ◽  
Margarita Albertovna Gagaro
Keyword(s):  
Adipose Tissue ◽  
Metabolic Disorders ◽  
Physiological Role ◽  
Biologically Active ◽  
Endocrine Function ◽  
Systemic Level ◽  
Tissue Sensitivity ◽  
And Storage ◽  
Active Substances

Adipose tissue serves not only as a place for the accumulation and storage of triacylglycerides as energy substrates, but also produces many hormone-like substances, mediators, cytokines, chemokines that act at the local and systemic level and aff ect metabolism, regulate tissue sensitivity to insulin, reproductive and the immune system. The review presents the current results of scientifi c research on the problem of the physiological role of biologically active substances produced by adipose tissue and their participation in the development of metabolic disorders.

scholarly journals Modulation of Type I Iodothyronine 5’-Deiodinase Activity in white Adipose Tissue by Nutrition: Possible Involvement of Leptin

2010 ◽  
pp. 561-569
Author(s):  
Z Macek Jílková ◽  
S Pavelka ◽  
P Flachs ◽  
M Hensler ◽  
V Kůs ◽  
...  
Keyword(s):  
Adipose Tissue ◽  
Caloric Restriction ◽  
White Adipose Tissue ◽  
Type I ◽  
Metabolizing Enzymes ◽  
Tissue Metabolism ◽  
Brown Adipose ◽  
Plasma Leptin ◽  
White Fat

Adipose tissue is an important target for thyroid hormones (TH). However, the metabolism of TH in white adipose tissue is poorly characterized. Our objective was to describe possible changes in activities of TH-metabolizing enzymes in white adipose tissue, and the role of TH metabolism in the tissue during obesogenic treatment, caloric restriction and in response to leptin in mice. Activity of type I iodothyronine 5’-deiodinase (D1) in white fat was stimulated by a high-fat diet, which also increased plasma leptin levels, while brown adipose tissue D1 activity did not change. Caloric restriction decreased the activity of D1 in white fat (but not in the liver), reduced leptin levels, and increased the expression of stearoyl CoA desaturase 1 (SCD-1), a marker and mediator of the effect of leptin on tissue metabolism. Leptin injections increased D1 activity and down-regulated SCD-1 in white fat. Our results demonstrate changes in D1 activity in white adipose tissue under the conditions of changing adiposity, and a stimulatory effect of leptin on D1 activity in the tissue. These results suggest a functional role for D1 in white adipose tissue, with D1 possibly being involved in the control of adipose tissue metabolism and/or accumulation of the tissue.

scholarly journals Emerging Roles for Browning of White Adipose Tissue in Prostate Cancer Malignant Behaviour

2021 ◽  
Vol 22 (11) ◽  
pp. 5560
Author(s):  
Alejandro Álvarez-Artime ◽  
Belén García-Soler ◽  
Rosa María Sainz ◽  
Juan Carlos Mayo
Keyword(s):  
Prostate Cancer ◽  
Adipose Tissue ◽  
White Adipose Tissue ◽  
Tumor Development ◽  
Cell Types ◽  
Protective Role ◽  
Bioactive Molecules ◽  
Brown Adipose ◽  
Endocrine Organs

In addition to its well-known role as an energy repository, adipose tissue is one of the largest endocrine organs in the organism due to its ability to synthesize and release different bioactive molecules. Two main types of adipose tissue have been described, namely white adipose tissue (WAT) with a classical energy storage function, and brown adipose tissue (BAT) with thermogenic activity. The prostate, an exocrine gland present in the reproductive system of most mammals, is surrounded by periprostatic adipose tissue (PPAT) that contributes to maintaining glandular homeostasis in conjunction with other cell types of the microenvironment. In pathological conditions such as the development and progression of prostate cancer, adipose tissue plays a key role through paracrine and endocrine signaling. In this context, the role of WAT has been thoroughly studied. However, the influence of BAT on prostate tumor development and progression is unclear and has received much less attention. This review tries to bring an update on the role of different factors released by WAT which may participate in the initiation, progression and metastasis, as well as to compile the available information on BAT to discuss and open a new field of knowledge about the possible protective role of BAT in prostate cancer.

scholarly journals Interactive effects of aging and aerobic capacity on energy metabolism–related metabolites of serum, skeletal muscle, and white adipose tissue

GeroScience ◽  
2021 ◽  
Author(s):  
Haihui Zhuang ◽  
Sira Karvinen ◽  
Timo Törmäkangas ◽  
Xiaobo Zhang ◽  
Xiaowei Ojanen ◽  
...  
Keyword(s):  
Adipose Tissue ◽  
Amino Acid ◽  
White Adipose Tissue ◽  
Aerobic Capacity ◽  
Amino Acid Metabolism ◽  
Acid Metabolism ◽  
Disease Risk ◽  
Whole Body ◽  
Whole Body Metabolism

AbstractAerobic capacity is a strong predictor of longevity. With aging, aerobic capacity decreases concomitantly with changes in whole body metabolism leading to increased disease risk. To address the role of aerobic capacity, aging, and their interaction on metabolism, we utilized rat models selectively bred for low and high intrinsic aerobic capacity (LCRs/HCRs) and compared the metabolomics of serum, muscle, and white adipose tissue (WAT) at two time points: Young rats were sacrificed at 9 months of age, and old rats were sacrificed at 21 months of age. Targeted and semi-quantitative metabolomics analysis was performed on the ultra-pressure liquid chromatography tandem mass spectrometry (UPLC-MS) platform. The effects of aerobic capacity, aging, and their interaction were studied via regression analysis. Our results showed that high aerobic capacity is associated with an accumulation of isovalerylcarnitine in muscle and serum at rest, which is likely due to more efficient leucine catabolism in muscle. With aging, several amino acids were downregulated in muscle, indicating more efficient amino acid metabolism, whereas in WAT less efficient amino acid metabolism and decreased mitochondrial β-oxidation were observed. Our results further revealed that high aerobic capacity and aging interactively affect lipid metabolism in muscle and WAT, possibly combating unfavorable aging-related changes in whole body metabolism. Our results highlight the significant role of WAT metabolism for healthy aging.

scholarly journals PO-043 The Effects of One-Time High Intensity Intermittent Training on Expression of LC3 Gene in Rats’ White Adipose Tissue

2018 ◽  
Vol 1 (3) ◽  
Author(s):  
Qishu Zhou ◽  
Chunyu Liang ◽  
Yafei Li ◽  
Yi Yan
Keyword(s):  
Adipose Tissue ◽  
White Adipose Tissue ◽  
High Intensity ◽  
High Fat Diet ◽  
Intermittent Exercise ◽  
Diet Group ◽  
Control Group ◽  
High Fat ◽  
Subcutaneous White Adipose Tissue ◽  
White Fat

Objective  To investigate the effect of one-time high-intensity intermittent exercise in white fat autophagy in obese rats and provide a theoretical basis of the molecular mechanism of exercise fat loss. Methods  Eighteen male 3-weeks-old rats were selected and divided into control group fed with normal diet (C), high-fat diet group fed with high fat diet (H). After 16 weeks, there were twelve obesity rats that divided into diet group (HS) and exercise group (HE). The other six control group rats of 19 weeks age were used as the standard (CS group). OE group did the high intensity intermittent exercise once. The CS group and the CS group were kept quietly. Three groups were taken subcutaneous white adipose tissue(S) and epididymal white adipose tissue (E) immediately after exercise. Mensurate the expression of LC3 gene in the tissue using the fluorescent quantitative PCR. Results 1. The expression of LC3 mRNA from white fat tissue was different to the tissues, which the expression of epididymal white adipose tissue of each group was higher than that in subcutaneous white adipose tissue (P <0.01). 2. Compared with CS group, the expression of epididymal white fat adipose tissue LC3 mRNA decreased (P<0.01) and the expression of the subcutaneous white adipose tissue increased from HS group (P <0.05). 3. Compared with OS group, the expression of epididymal white fat adipose tissue LC3 mRNA decreased (P<0.05) and the expression of subcutaneous white adipose tissue decreased from OS group. Conclusions The expression of LC3mRNA in epididymal white fat adipose tissue of rats was significantly higher than that of subcutaneous white fat. The changes of LC3mRNA expression of adipose tissue caused by high-fat diet have tissue differences. One-time high-intensity intermittent exercise can reduce the expression of LC3mRNA in fat tissue of obese rats. Its regulatory mechanism needs to be further studied.

scholarly journals Aging-related inflammation driven by cellular senescence enhances NAD consumption via activation of CD38+pro-inflammatory macrophages

2019 ◽  
Author(s):  
Anthony J. Covarrubias ◽  
Abhijit Kale ◽  
Rosalba Perrone ◽  
Jose Alberto Lopez-Dominguez ◽  
Angela Oliveira Pisco ◽  
...  
Keyword(s):  
Adipose Tissue ◽  
Inflammatory Cytokines ◽  
Cellular Senescence ◽  
White Adipose Tissue ◽  
Causal Link ◽  
Secretory Proteins ◽  
M2 Macrophages ◽  
Therapeutic Opportunity ◽  
Inflammatory Macrophages ◽  
Novel Therapeutic

SummaryDecline in tissue NAD levels during aging is linked to aging and its associated diseases. However, the mechanism for aging-associated NAD decline remains unclear. Here we report that pro-inflammatory M1-like macrophages, but not naïve or M2 macrophages, accumulate in metabolic tissues including visceral white adipose tissue and the liver during aging. Remarkably, these M1-like macrophages highly express the NAD consuming enzyme CD38 and have enhanced CD38-dependent NADase activity. We also find that senescent cells progressively accumulate in visceral white adipose tissue during aging and that inflammatory cytokines found in the supernatant from senescent cells (Senescence associated secretory proteins, SASP) induce macrophages to proliferate and to express CD38. These results highlight a new causal link between visceral tissue senescence and tissue NAD decline during aging and represent a novel therapeutic opportunity targeting maintenance of NAD levels during aging.

Sign in / Sign up

Export Citation Format

Share Document