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Cells Nov 2021In recent years, there has been a large amount of evidence on the role of microRNA (miRNA) in regulating adipose tissue physiology. Indeed, miRNAs control critical steps... (Review)
Review
In recent years, there has been a large amount of evidence on the role of microRNA (miRNA) in regulating adipose tissue physiology. Indeed, miRNAs control critical steps in adipocyte differentiation, proliferation and browning, as well as lipolysis, lipogenesis and adipokine secretion. Overnutrition leads to a significant change in the adipocyte miRNOME, resulting in adipose tissue dysfunction. Moreover, via secreted mediators, dysfunctional adipocytes may impair the function of other organs and tissues. However, given their potential to control cell and whole-body energy expenditure, miRNAs also represent critical therapeutic targets for treating obesity and related metabolic complications. This review attempts to integrate present concepts on the role miRNAs play in adipose tissue physiology and obesity-related dysfunction and data from pre-clinical and clinical studies on the diagnostic or therapeutic potential of miRNA in obesity and its related complications.
Topics: Adipogenesis; Adipokines; Adipose Tissue; Gene Expression Regulation; Humans; Insulin Resistance; MicroRNAs
PubMed: 34943849
DOI: 10.3390/cells10123342 -
International Journal of Molecular... Aug 2020Semaphorins are a family originally identified as axonal guidance molecules. They are also involved in tumor growth, angiogenesis, immune regulation, as well as other... (Review)
Review
Semaphorins are a family originally identified as axonal guidance molecules. They are also involved in tumor growth, angiogenesis, immune regulation, as well as other biological and pathological processes. Recent studies have shown that semaphorins play a role in metabolic diseases including obesity, adipose inflammation, and diabetic complications, including diabetic retinopathy, diabetic nephropathy, diabetic neuropathy, diabetic wound healing, and diabetic osteoporosis. Evidence provides mechanistic insights regarding the role of semaphorins in metabolic diseases by regulating adipogenesis, hypothalamic melanocortin circuit, immune responses, and angiogenesis. In this review, we summarize recent progress regarding the role of semaphorins in obesity, adipose inflammation, and diabetic complications.
Topics: Adipose Tissue; Animals; Diabetes Complications; Humans; Metabolic Diseases; Models, Biological; Semaphorins
PubMed: 32781674
DOI: 10.3390/ijms21165641 -
Nutrients Mar 2023White adipose tissue (AT) dysfunction plays an important role in the development of cardiometabolic alterations associated with obesity. AT dysfunction is characterized... (Review)
Review
White adipose tissue (AT) dysfunction plays an important role in the development of cardiometabolic alterations associated with obesity. AT dysfunction is characterized by the loss of the expansion capacity of the AT, an increment in adipocyte hypertrophy, and changes in the secretion profile of adipose cells, associated with accumulation of macrophages and inflammation. Since not all people with an excess of adiposity develop comorbidities, it is necessary to find simple tools that can evidence AT dysfunction and allow the detection of those people with the potential to develop metabolic alterations. This review focuses on the current pathophysiological mechanisms of white AT dysfunction and emerging measurements to assess its functionality.
Topics: Humans; Obesity; Adipose Tissue, White; Adiposity; Adipocytes; Inflammation; Adipose Tissue
PubMed: 37049561
DOI: 10.3390/nu15071722 -
International Journal of Molecular... Aug 2021Brown adipose tissue (BAT), a uniquely thermogenic tissue that plays an important role in metabolism and energy expenditure, has recently become a revived target in the... (Review)
Review
Brown adipose tissue (BAT), a uniquely thermogenic tissue that plays an important role in metabolism and energy expenditure, has recently become a revived target in the fight against metabolic diseases, such as obesity, diabetes, and non-alcoholic fatty liver disease (NAFLD). Different from white adipose tissue (WAT), the brown adipocytes have distinctive features including multilocular lipid droplets, a large number of mitochondria, and a high expression of uncoupling protein-1 (UCP-1), as well as abundant capillarity. These histologic characteristics provide an opportunity to differentiate BAT from WAT using imaging modalities, such as PET/CT, SPECT/CT, MRI, NIRF and Ultrasound. However, most of the reported imaging methods were BAT activation dependent, and the imaging signals could be affected by many factors, including environmental temperatures and the states of the sympathetic nervous system. Accurate BAT mass detection methods that are independent of temperature and hormone levels have the capacity to track the development and changes of BAT throughout the lifetime of mammals, and such methods could be very useful for the investigation of potential BAT-related therapies. In this review, we focus on molecular imaging modalities that can detect and quantify BAT mass. In addition, their detection mechanism and limitations will be discussed as well.
Topics: Adipose Tissue, Brown; Adipose Tissue, White; Animals; Humans; Metabolic Diseases; Molecular Imaging
PubMed: 34502347
DOI: 10.3390/ijms22179436 -
Acta Pharmacologica Sinica Feb 2022The excess deposition of underlying extracellular matrix (ECM) in adipose tissue is defined as adipose tissue fibrosis that is a major contributor to metabolic disorder...
The excess deposition of underlying extracellular matrix (ECM) in adipose tissue is defined as adipose tissue fibrosis that is a major contributor to metabolic disorder such as obesity and type 2 diabetes. Anti-fibrosis therapy has received much attention in the treatment of metabolic disorders. Orosomucoid (ORM) is an acute-phase protein mainly produced by liver, which is also an adipokine. In this study, we investigated the effects of ORM on adipose tissue fibrosis and the potential mechanisms. We showed that ORM1-deficient mice exhibited an obese phenotype, manifested by excessive collagen deposition in adipose tissues and elevated expression of ECM regulators such as metalloproteinases (MMP-2, MMP-13, MMP-14) and tissue inhibitors of metalloproteinases (TIMP-1, TIMP-2, TIMP-3). Administration of exogenous ORM (50 mg· kg· d, ip) for 7 consecutive days in high-fat diet (HFD)-fed mice and leptin receptor (LepR)-deficient db/db mice attenuated these abnormal expressions. Meanwhile, ORM administration stimulated AMP-activated protein kinase (AMPK) phosphorylation and decreased transforming growth factor-β1 (TGF-β1) level in adipose tissues of the mice. In TGF-β1-treated 3T3-L1 fibroblasts, ORM (10 μg/mL) improved the impaired expression profiles of fibrosis-related genes, whereas a selective AMPK inhibitor dorsomorphin (1 μmol/mL) abolished these effects. Together, our results suggest that ORM exerts a direct anti-fibrosis effect in adipose tissue via AMPK activation. ORM is expected to become a novel target for the treatment of adipose tissue fibrosis.
Topics: 3T3 Cells; AMP-Activated Protein Kinases; Adipokines; Adipose Tissue; Animals; Blotting, Western; Diet, High-Fat; Fibrosis; Magnetic Resonance Imaging; Male; Mice; Mice, Inbred C57BL; Orosomucoid; Signal Transduction
PubMed: 33875797
DOI: 10.1038/s41401-021-00666-9 -
Current Opinion in Genetics &... Jun 2023Adipose tissue is a heterogeneous organ, comprising cell types, including mature adipocytes, progenitor cells, immune cells, and vascular cells. Here, we discuss the... (Review)
Review
Adipose tissue is a heterogeneous organ, comprising cell types, including mature adipocytes, progenitor cells, immune cells, and vascular cells. Here, we discuss the heterogeneity of human and mouse white adipose tissue in general and white adipocytes specifically, focusing on how our understanding of adipocyte subpopulations has expanded with the advent of single nuclear RNA sequencing and spatial transcriptomics. Furthermore, we discuss critical remaining questions regarding how these distinct populations arise, how their functions differ from one another, and which potentially contribute to metabolic pathophysiology.
Topics: Humans; Adipose Tissue, White; Adipose Tissue; Adipocytes, White; Stem Cells
PubMed: 37094486
DOI: 10.1016/j.gde.2023.102045 -
Frontiers in Immunology 2020Adipocytes are the largest cell type in terms of volume, but not number, in adipose tissue. Adipocytes are prominent contributors to systemic metabolic health. Obesity,... (Review)
Review
Adipocytes are the largest cell type in terms of volume, but not number, in adipose tissue. Adipocytes are prominent contributors to systemic metabolic health. Obesity, defined by excess adipose tissue (AT), is recognized as a low-grade chronic inflammatory state. Cytokines are inflammatory mediators that are produced in adipose tissue (AT) and function in both AT homeostatic as well as pathological conditions. AT inflammation is associated with systemic metabolic dysfunction and obesity-associated infiltration and proliferation of immune cells occurs in a variety of fat depots in mice and humans. AT immune cells secrete a variety of chemokines and cytokines that act in a paracrine manner on adjacent adipocytes. TNFα, IL-6, and MCP-1, are well studied mediators of AT inflammation. Oncostatin M (OSM) is another proinflammatory cytokine that is elevated in AT in human obesity, and its specific receptor (OSMRβ) is also induced in conditions of obesity and insulin resistance. OSM production and paracrine signaling in AT regulates adipogenesis and the functions of AT. This review summarizes the roles of the oncostatin M receptor (OSMRβ) as a modulator of adipocyte development and function its contributions to immunological adaptations in AT in metabolic disease states.
Topics: Adipocytes; Adipose Tissue; Animals; Energy Metabolism; Homeostasis; Humans; Inflammation Mediators; Insulin Resistance; Obesity; Oncostatin M; Oncostatin M Receptor beta Subunit; Panniculitis; Signal Transduction
PubMed: 33854494
DOI: 10.3389/fimmu.2020.612013 -
Nutrients Nov 2023The quality and quantity of the food we consume have a major impact on our general health and longevity [...].
The quality and quantity of the food we consume have a major impact on our general health and longevity [...].
Topics: Adipose Tissue; Eating
PubMed: 38004204
DOI: 10.3390/nu15224811 -
Adipocyte Dec 2021Exosomes are nano-sized extracellular vesicles (30-160 nm diameter) with lipid bilayer membrane secrete by various cells that mediate the communication between cells... (Review)
Review
Exosomes are nano-sized extracellular vesicles (30-160 nm diameter) with lipid bilayer membrane secrete by various cells that mediate the communication between cells and tissue, which contain a variety of non-coding RNAs, mRNAs, proteins, lipids and other functional substances. Adipose tissue is important energy storage and endocrine organ in the organism. Recent studies have revealed that adipose tissue-derived exosomes (AT-Exosomes) play a critical role in many physiologically and pathologically functions. Physiologically, AT-Exosomes could regulate the metabolic homoeostasis of various organs or cells including liver and skeletal muscle. Pathologically, they could be used in the treatment of disease and or that they may be involved in the progression of the disease. In this review, we describe the basic principles and methods of exosomes isolation and identification, as well as further summary the specific methods. Moreover, we categorize the relevant studies of AT-Exosomes and summarize the different components and biological functions of mammalian exosomes. Most importantly, we elaborate AT-Exosomes crosstalk within adipose tissue and their functions on other tissues or organs from the physiological and pathological perspective. Based on the above analysis, we discuss what remains to be discovered problems in AT-Exosomes studies and prospect their directions needed to be further explored in the future.
Topics: Adipose Tissue; Animals; Biological Transport; Exosomes; Extracellular Vesicles; Homeostasis
PubMed: 34709975
DOI: 10.1080/21623945.2021.1983242 -
Journal of Molecular Cell Biology Oct 2020The obesity epidemic continues to rise as a global health challenge. Thermogenic brown and beige adipocytes dissipate chemical energy as heat, providing an opportunity... (Review)
Review
The obesity epidemic continues to rise as a global health challenge. Thermogenic brown and beige adipocytes dissipate chemical energy as heat, providing an opportunity for developing new therapeutics for obesity and related metabolic diseases. Anatomically, brown adipose tissue is distributed as discrete depots, while beige adipocytes exist within certain depots of white adipose tissue. Developmentally, brown and beige adipocytes arise from multiple embryonic progenitor populations that are distinct and overlapping. Functionally, they respond to a plethora of stimuli to engage uncoupling protein 1-dependent and independent thermogenic programs, thus improving systemic glucose homeostasis, lipid metabolism, and the clearance of branched-chain amino acids. In this review, we highlight recent advances in our understanding of the molecular and cellular mechanisms that contribute to the developmental and functional heterogeneity of thermogenic adipose tissue.
Topics: Adipocytes; Adipose Tissue; Aging; Animals; Cell Lineage; Humans; Models, Biological; Thermogenesis
PubMed: 32569352
DOI: 10.1093/jmcb/mjaa029