Mest/Peg1 imprinted gene enlarges adipocytes and is a marker of adipocyte size

2005 ◽  
Vol 288 (1) ◽  
pp. E117-E124 ◽  
Author(s):  
Mayumi Takahashi ◽  
Yasutomi Kamei ◽  
Osamu Ezaki
Keyword(s):  
Gene Expression ◽  
Adipose Tissue ◽  
Transgenic Mice ◽  
Type Ii Diabetes ◽  
Binding Protein ◽  
Ectopic Expression ◽  
Peroxisome Proliferator ◽  
Type Ii ◽  
Fatty Acid Binding ◽  
Enhanced Expression

Obesity is a common and serious metabolic disorder in the developed world that is occasionally accompanied by type II diabetes, atherosclerosis, hypertension, and hyperlipidemia. We have found that mesoderm-specific transcript (Mest)/paternally expressed gene 1 (Peg1) gene expression was markedly enhanced in white adipose tissue of mice with diet-induced and genetically caused obesity/diabetes but not with streptozotocin-induced diabetes, which does not cause obesity. Administration of pioglitazone, a drug for type II diabetes and activator of peroxisome proliferator-activated receptor (PPAR)γ, in obese db/ db mice reduced the enhanced expression of Mest mRNA in adipose tissue, concomitant with an increase in body weight and a decrease in the size of adipose cells. Ectopic expression of Mest in 3T3-L1 cells caused increased gene expression of adipose markers such as PPARγ, CCAAT/enhancer binding protein (C/EBP)α, and adipocyte fatty acid binding protein (aP)2. In transgenic mice overexpressing Mest in adipose tissue, enhanced expression of the adipose genes was observed. Moreover, adipocytes were markedly enlarged in the transgenic mice. Thus Mest appears to enlarge adipocytes and could be a novel marker of the size of adipocytes.

Agouti regulates adipocyte transcription factors

2001 ◽  
Vol 280 (4) ◽  
pp. C954-C961 ◽  
Author(s):  
Randall L. Mynatt ◽  
Jacqueline M. Stephens
Keyword(s):  
Adipose Tissue ◽  
Transgenic Mice ◽  
Ectopic Expression ◽  
Peroxisome Proliferator ◽  
Paracrine Factor ◽  
Peroxisome Proliferator Activated Receptor ◽  
Protein Levels ◽  
Skeletal Mass ◽  
Ppar Γ ◽  
Obesity And Diabetes

Agouti is a secreted paracrine factor that regulates pigmentation in hair follicle melanocytes. Several dominant mutations cause ectopic expression of agouti, resulting in a phenotype characterized by yellow fur, adult-onset obesity and diabetes, increased linear growth and skeletal mass, and increased susceptibility to tumors. Humans also produce agouti protein, but the highest levels of agouti in humans are found in adipose tissue. To mimic the human agoutiexpression pattern in mice, transgenic mice (aP2-agouti) that express agouti in adipose tissue were generated. The transgenic mice develop a mild form of obesity, and they are sensitized to the action of insulin. We correlated the levels of specific regulators of insulin signaling and adipocyte differentiation with these phenotypic changes in adipose tissue. Signal transducers and activators of transcription (STAT)1, STAT3, and peroxisome proliferator-activated receptor (PPAR)-γ protein levels were elevated in the transgenic mice. Treatment of mature 3T3-L1 adipocytes recapitulated these effects. These data demonstrate that agouti has potent effects on adipose tissue. We hypothesize that agouti increases adiposity and promotes insulin sensitivity by acting directly on adipocytes via PPAR-γ.

Effects of Deep Sea Water on Anti-Obesity Properties in Induction of Beige Adipocytes

2019 ◽  
Vol 13 (1) ◽  
pp. 38-48
Author(s):  
Samihah Z.M. Nani ◽  
Abubakar Jaafar ◽  
Fadzilah A.A. Majid ◽  
Akbariah Mahdzir ◽  
Md. Nor Musa
Keyword(s):  
Adipose Tissue ◽  
Deep Sea ◽  
Sea Water ◽  
Binding Protein ◽  
Uncoupling Protein ◽  
Peroxisome Proliferator ◽  
Peroxisome Proliferator Activated Receptor ◽  
Fatty Acid Binding ◽  
Deep Sea Water ◽  
Beige Adipocytes

Objective: Deep sea water (DSW) accumulates many scientific shreds of evidence in treating obesity. Previous studies indicated that it reduces white adipose tissue (WAT) and body weight. WAT is energy storage fat, while beige adipose tissue is energy supply fat. In this study, the effects of DSW in the induction of beige adipocytes from mouse adipose tissue-derived stromal vascular fraction (SVF) cells are determined. Methods: Adipose tissue-derived SVF cells were isolated from mice and used for induction of beige adipocytes and treated with DSW at several concentrations. Results: During the course of beige adipocytes differentiation, DSW treatment increased lipid accumulation and upregulated adipogenic genes markers expression such as peroxisome proliferator-activated receptor-γ (PPAR-γ), CCAAT/enhancer-binding protein a (C/EBP-α), and fatty acid binding protein 4 (FABP4), and also upregulated thermogenic genes markers such as the uncoupling protein 1 (UCP-1), peroxisome proliferator-activated receptor gamma coactivator 1-alpha (PGC-1α), and cell deathinducing DFFA-like effector A (Cidea) in beige adipocytes. Conclusion: DSW has the potential to promote browning of WAT and upregulates the thermogenic genes that are responsible for energy expenditure.

Involvement of SIK2/TORC2 signaling cascade in the regulation of insulin-induced PGC-1α and UCP-1 gene expression in brown adipocytes

2009 ◽  
Vol 296 (6) ◽  
pp. E1430-E1439 ◽  
Author(s):  
Masaaki Muraoka ◽  
Aiko Fukushima ◽  
Say Viengchareun ◽  
Marc Lombès ◽  
Fukuko Kishi ◽  
...  
Keyword(s):  
Gene Expression ◽  
Transgenic Mice ◽  
Binding Protein ◽  
Uncoupling Protein ◽  
Brown Adipocytes ◽  
Adipose Tissues ◽  
Fatty Acid Binding ◽  
Diet Induced Obesity ◽  
Brown Adipose ◽  
The Impact

Salt-inducible kinase 2 (SIK2) is expressed abundantly in adipose tissues and represses cAMP-response element-binding protein (CREB)-mediated gene expression by phosphorylating the coactivator transducer of regulated CREB activity (TORC2). Phosphorylation at Ser587 of SIK2 diminishes its TORC2 phosphorylation activity. In 3T3-L1 white adipocytes, SIK2 downregulates lipogenic gene in response to nutritional stresses. To investigate the impact of SIK2 on the function of brown adipose tissue (BAT), we used T37i brown adipocytes, mice with diet-induced obesity, and SIK2 mutant (S587A) transgenic mice. When T37i adipocytes were treated with insulin, the levels of peroxisome proliferator-activated receptor-coactivator-1α ( PGC-1α) and uncoupling protein-1 ( UCP-1) mRNA were increased, and the induction was inhibited by overexpression of SIK2 (S587A) mutant or dominant-negative CREB. Insulin enhanced SIK2 phosphorylation at Ser587, which was accompanied by decrease in phospho-TORC2. Similarly, the decrease in the level of SIK2 phosphorylation at Ser587 was observed in the BAT of mice with diet-induced obesity, which was negatively correlated with TORC2 phosphorylation. To confirm the negative correlation between SIK2 phosphorylation at Ser587 and TORC2 phosphorylation in BAT, SIK2 mutant (S587A) was overexpressed in adipose tissues by using the adipocyte fatty acid-binding protein 2 promoter. The expression of recombinant SIK2 (S587A) was restricted to BAT, and the levels of phospho-TORC2 were elevated in BAT of transgenic mice. Male transgenic mice developed high-fat diet-induced obesity, and their BAT expressed low levels of PGC-1α and UCP-1 mRNA, suggesting that SIK2-TORC2 cascade may be important for the regulation of PGC-1α and UCP-1 gene expression in insulin signaling in BAT.

scholarly journals Serum- and Glucocorticoid-Inducible Kinase 1 (SGK1) Regulates Adipocyte Differentiation via Forkhead Box O1

2010 ◽  
Vol 24 (2) ◽  
pp. 370-380 ◽  
Author(s):  
Natalia Di Pietro ◽  
Valentine Panel ◽  
Schantel Hayes ◽  
Alessia Bagattin ◽  
Sunitha Meruvu ◽  
...  
Keyword(s):  
Cellular Localization ◽  
Adipocyte Differentiation ◽  
Binding Protein ◽  
Ectopic Expression ◽  
Peroxisome Proliferator ◽  
Mrna Levels ◽  
Peroxisome Proliferator Activated Receptor ◽  
Fatty Acid Binding ◽  
Mesenchymal Precursor Cells ◽  
And Function

Abstract The serum and glucocorticoid-inducible kinase 1 (SGK1) is an inducible kinase the physiological function of which has been characterized primarily in the kidney. Here we show that SGK1 is expressed in white adipose tissue and that its levels are induced in the conversion of preadipocytes into fat cells. Adipocyte differentiation is significantly diminished via small interfering RNA inhibition of endogenous SGK1 expression, whereas ectopic expression of SGK1 in mesenchymal precursor cells promotes adipogenesis. The SGK1-mediated phenotypic effects on differentiation parallel changes in the mRNA levels for critical regulators and markers of adipogenesis, such as peroxisome proliferator-activated receptor γ, CCAAT enhancer binding protein α, and fatty acid binding protein aP2. We demonstrate that SGK1 affects differentiation by direct phosphorylation of Foxo1, thereby changing its cellular localization from the nucleus to the cytosol. In addition we show that SGK1−/− cells are unable to relocalize Foxo1 to the cytosol in response to dexamethasone. Together these results show that SGK1 influences adipocyte differentiation by regulating Foxo1 phosphorylation and reveal a potentially important function for this kinase in the control of fat mass and function.

scholarly journals Troglitazone Effects on Gene Expression in Human Skeletal Muscle of Type II Diabetes Involve Up-Regulation of Peroxisome Proliferator-Activated Receptor-γ1

1998 ◽  
Vol 83 (8) ◽  
pp. 2830-2835 ◽  
Author(s):  
Kyong Soo Park ◽  
Theodore P. Ciaraldi ◽  
Kristin Lindgren ◽  
Leslie Abrams-Carter ◽  
Sunder Mudaliar ◽  
...  
Keyword(s):  
Gene Expression ◽  
Skeletal Muscle ◽  
Type Ii Diabetes ◽  
Insulin Action ◽  
Peroxisome Proliferator ◽  
Type Ii ◽  
Peroxisome Proliferator Activated Receptor ◽  
Nondiabetic Control ◽  
Muscle Cultures ◽  
Stimulation Of

abstract Troglitazone, besides improving insulin action in insulin-resistant subjects, is also a specific ligand for the nuclear receptor peroxisome proliferator-activated receptor-γ (PPARγ). To determine whether troglitazone might enhance insulin action by stimulation of PPARγ gene expression in muscle, total PPARγ messenger RNA (mRNA), and protein were determined in skeletal muscle cultures from nondiabetic control and type II diabetic subjects before and after treatment of cultures with troglitazone (4 days ± troglitazone, 11.5μ m). Troglitazone treatment increased PPARγ mRNA levels up to 3-fold in muscle cultures from type II diabetics (277 ± 63 to 630 ± 100 × 103 copies/μg total RNA, P = 0.003) and in nondiabetic control subjects (200 ± 42 to 490 ± 81, P = 0.003). PPARγ protein levels in both diabetic (4.7 ± 1.6 to 13.6± 3.0 AU/10 μg protein, P < 0.02) and nondiabetic cells (7.4 ± 1.0 to 12.7 ± 1.8, P < 0.05) were also up-regulated by troglitazone treatment. Increased PPARγ was associated with stimulation of human adipocyte lipid binding protein (ALBP) and muscle fatty acid binding protein (mFABP) mRNA, without change in the mRNA for glycerol-3-phosphate dehydrogenase, PPARδ, myogenin, uncoupling protein-2, or sarcomeric α-actin protein. In summary, we showed that troglitazone markedly induces PPARγ, ALBP, and mFABP mRNA abundance in muscle cultures from both nondiabetic and type II diabetic subjects. Increased expression of PPARγ protein and other genes involved in glucose and lipid metabolism in skeletal muscle may account, in part, for the insulin sensitizing effects of troglitazone in type II diabetes.

Obesity, Type II diabetes and the Ala54Thr polymorphism of fatty acid binding protein 2 in the Tongan population

2003 ◽  
Vol 79 (3) ◽  
pp. 183-188 ◽  
Author(s):  
Natalia L Duarte ◽  
Stephen Colagiuri ◽  
Taniela Palu ◽  
Xing Li Wang ◽  
David E.L Wilcken
Keyword(s):  
Fatty Acid ◽  
Type Ii Diabetes ◽  
Fatty Acid Binding Protein ◽  
Binding Protein ◽  
Type Ii ◽  
Fatty Acid Binding ◽  
Acid Binding Protein
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