Regulation of the leptin content of obese human adipose tissue

The objective of this study was to determine whether obese human adipose tissue contains preformed stores of leptin and their relationship to secreted leptin. Detergent increased detectable leptin by about twofold, suggesting that leptin is stored in a membrane-bound location. Subcutaneous tissue leptin was ∼1.6-fold higher than omental, paralleling known differences in leptin secretion and expression. The amount of leptin secreted during a 3-h incubation was similar to that of extractable tissue leptin. Tissue leptin levels were maintained over the incubation. Inhibition of protein synthesis decreased tissue leptin content but did not decrease leptin secretion until after 3 h of incubation. Culture of adipose tissue for 2 days with the combination of insulin and dexamethasone, but not with either hormone alone, increased tissue leptin content about twofold in both depots. Although insulin did not affect tissue leptin content, it potentiated leptin secretion (as a % of tissue stores). These data suggest that adipose tissue leptin storage and secretion per se are regulated. Regulation of the release of preformed leptin may modulate serum leptin levels in obese humans.

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Influence of age, fat cell weight, and obesity on O2 consumption of human adipose tissue

AJP Endocrinology and Metabolism ◽

10.1152/ajpendo.1989.256.4.e467 ◽

1989 ◽

Vol 256 (4) ◽

pp. E467-E474 ◽

Cited By ~ 6

Author(s):

P. Hallgren ◽

L. Sjostrom ◽

H. Hedlund ◽

L. Lundell ◽

L. Olbe

Keyword(s):

Adipose Tissue ◽

Oxygen Consumption ◽

Energy Expenditure ◽

Human Adipose Tissue ◽

Fat Cell ◽

Cell Weight ◽

Total Body ◽

Obese Human ◽

Open Question ◽

Partial Weight

The oxygen consumption of human adipose tissue (AT) was determined in 53 adults, lean and obese, and in nine lean boys. The oxygen consumption was positively related to fat cell weight and negatively to age and degree of obesity. Men and women did not differ with respect to oxygen consumption of AT. The positive relationship between oxygen consumption per cell and fat cell size was also demonstrated in size-separated cells from the same donors. Expressed per cell the oxygen consumption was higher in fat cells from obese than in cells from lean subjects, but expressed per gram of tissue the opposite result was found. The oxygen consumption of the total AT organ was higher in obese than in lean subjects. The energy expenditure of AT constituted approximately 4% of the estimated 24-h energy expenditure in both groups. It is concluded that obese subjects do not maintain their obesity because of a reduced energy expenditure of the total AT (or of the total body). After a partial weight reduction in five subjects, the energy metabolism tended to change in direction toward the conditions seen in lean subjects. However, it is still an open question whether the observed energy metabolic aberrations of obese human AT are only secondary to the obese state or partly primary and thus of etiological importance.

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Über den Gehalt an membrangebundenen und freien Ribosomen in Saccharomyceszellen nach Hemmung der Proteinsynthese mit Cycloheximid / The Content of Membrane-Bound and Free Ribosomes in Saccharomyces after the Inhibition of Protein Synthesis with Cycloheximid

Zeitschrift für Naturforschung C ◽

10.1515/znc-1978-3-424 ◽

1978 ◽

Vol 33 (3-4) ◽

pp. 299-300 ◽

Cited By ~ 2

Author(s):

Joan Kraft-Creech ◽

Ingrid Pietsch ◽

Ernst-Randolf Lochmann

Keyword(s):

Protein Synthesis ◽

Untreated Control ◽

Yeast Cells ◽

Inhibition Of Protein Synthesis ◽

Membrane Bound

Abstract After the inhibition of protein synthesis in Saccharomyces cells with cycloheximid, the content of membrane-bound ribosomes decreases significantly, whereas the content of free ribosomes remains the same as the untreated control for a longer period of time. This is further evidence that in yeast cells protein synthesis takes place only on membrane-bound ribosomes.

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Stimulated in vivo synthesis of plasminogen activator inhibitor-1 in human adipose tissue

Thrombosis and Haemostasis ◽

10.1160/th11-11-0822 ◽

2012 ◽

Vol 108 (09) ◽

pp. 485-492 ◽

Cited By ~ 19

Author(s):

Jan Liska ◽

Per Eriksson ◽

Eva Sverremark-Ekström ◽

Per Tornvall ◽

Mattias Ekström

Keyword(s):

Gene Expression ◽

Protein Synthesis ◽

Adipose Tissue ◽

Plasminogen Activator ◽

Systemic Inflammation ◽

Plasminogen Activator Inhibitor ◽

Human Adipose Tissue ◽

Omental Adipose Tissue ◽

Pai 1

SummaryPlasminogen activator inhibitor type-1 (PAI-1) is one of the most important inhibitors of endogenous fibrinolysis. Adipose tissue is a suggested source of the elevated plasma levels of PAI-1 in obesity. The relation between PAI-1 and inflammation is of particular interest, but current knowledge regarding regulation of PAI-1 in adipose tissue is mainly based on animal studies or ex vivo experiments on human cultured adipocytes. So far, no study has described stimulated gene expression and protein synthesis of PAI-1 in vivo in human adipose tissue. We used open heart surgery as a model of acute systemic inflammation. Twenty-two male patients underwent blood sampling and omental and subcutaneous adipose tissue biopsies for gene expression studies before and after surgery. Expression and localisation of PAI-1 antigen was evaluated by immunohistochemistry. After surgery gene expression of PAI-1 increased 27-fold in omental adipose tissue and three-fold in subcutaneous adipose tissue, but no differences were found in tissue-type plasminogen activator (t-PA) mRNA. PAI-1 antigen was localised within endothelial cells and in the adipose tissue interstitium close to vessels. The upregulated gene expression and protein synthesis in adipose tissue was followed by increased concentrations of PAI-1 antigen in plasma. In conclusion, we present for the first time that an acute systemic inflammation in humans increased gene expression and protein synthesis of PAI-1 in adipose tissue and that this increase was most prominent in omental adipose tissue. PAI-1 synthesis in adipose tissue due to acute systemic inflammation may be a link between inflammation and impaired endogenous fibrinolysis.

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Characterization of stromal vascular fraction and adipose stem cells from subcutaneous, preperitoneal and visceral morbidly obese human adipose tissue depots

PLoS ONE ◽

10.1371/journal.pone.0174115 ◽

2017 ◽

Vol 12 (3) ◽

pp. e0174115 ◽

Cited By ~ 18

Author(s):

Karina Ribeiro Silva ◽

Isis Côrtes ◽

Sally Liechocki ◽

João Regis Ivar Carneiro ◽

Antônio Augusto Peixoto Souza ◽

...

Keyword(s):

Stem Cells ◽

Adipose Tissue ◽

Stromal Vascular Fraction ◽

Human Adipose Tissue ◽

Adipose Stem Cells ◽

Morbidly Obese ◽

Adipose Tissue Depots ◽

Obese Human

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Relationship between peroxisome proliferator-activated receptor gamma and retinoic acid receptor alpha gene expression in obese human adipose tissue

International Journal of Obesity ◽

10.1038/sj.ijo.0802025 ◽

2002 ◽

Vol 26 (7) ◽

pp. 920-927 ◽

Cited By ~ 20

Author(s):

A Redonnet ◽

S Bonilla ◽

C Noël-Suberville ◽

V Pallet ◽

H Dabadie ◽

...

Keyword(s):

Gene Expression ◽

Adipose Tissue ◽

Retinoic Acid ◽

Retinoic Acid Receptor ◽

Human Adipose Tissue ◽

Peroxisome Proliferator ◽

Retinoic Acid Receptor Alpha ◽

Peroxisome Proliferator Activated Receptor ◽

Alpha Gene ◽

Obese Human

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Histopathological Features of Tissue Alterations Induced by Cryolipolysis on Human Adipose Tissue

Aesthetic Surgery Journal ◽

10.1093/asj/sjaa035 ◽

2020 ◽

Vol 40 (7) ◽

pp. 761-766 ◽

Cited By ~ 1

Author(s):

Domenico Pugliese ◽

Fabrizio Melfa ◽

Enrico Guarino ◽

Eliano Cascardi ◽

Michela Maggi ◽

...

Keyword(s):

Adipose Tissue ◽

Histopathological Examination ◽

Subcutaneous Tissue ◽

Human Adipose Tissue ◽

Structural Reorganization ◽

Level Of Evidence ◽

Single Standard ◽

Tissue Alterations ◽

In Vivo Effects

Abstract Background Adipose tissue cooling, under controlled conditions, induces physical effects on subcutaneous tissue called cryolipolysis (CLL), which has been proposed as a method to reduce noninvasively the amount of adipose tissue. Although CLL has been widely utilized in clinical practice and many favorable results have been reported in clinical studies, very few published studies have dealt with the effects of such therapies on human adipose tissue. Objectives The aim of this study was to evaluate, through histopathological examination, the in vivo effects of CLL on human adipose tissue. Methods Six patients to be submitted to abdominoplasty were enrolled in the study. Samples were taken from the surgical patch, respectively, 15 days (2 pts), 45 days (2 pts), and 60 days (2 pts) after a single standard session of CLL. Control samples were derived from the nontreated areas of the surgical patch. Results Disruption of the adipocytic membranes was evident in all treated areas, with a reduction of cell dissolution in the 60-day samples. Focal dissolution and homogenization of the collagen fibers was evident, resulting in the dissolution of the interlobular fibrous septa. A mild inflammatory response was observed in the 15- and 45-day samples. Neocapillarizzation was observed in the 45- and 60-day samples. Conclusions The lesions demonstrated in adipocytes confirm the theoretical premises of a usefulness of CLL in the treatment of localized adiposis. The alterations in the connective stroma could lead to a structural reorganization and consequently to the in vivo external appearance of the treated areas. Level of Evidence: 5

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