Downregulated IRS-1 and PPARγ in obese women with gestational diabetes: relationship to FFA during pregnancy

2002 ◽  
Vol 282 (3) ◽  
pp. E522-E533 ◽  
Author(s):  
Patrick M. Catalano ◽  
Steven E. Nizielski ◽  
Jianhua Shao ◽  
Larraine Preston ◽  
Liping Qiao ◽  
...  
Keyword(s):  
Insulin Resistance ◽  
Adipose Tissue ◽  
Gestational Diabetes ◽  
Target Genes ◽  
Late Gestation ◽  
Peroxisome Proliferator ◽  
Mrna Levels ◽  
Obese Women ◽  
Cellular Mechanisms ◽  
Fatty Acid Binding

Gestational diabetes mellitus (GDM) is associated with elevated postprandial free fatty acids (FFA) and insulin resistance; however, little is known about the cellular mechanisms underlying insulin resistance to suppress lipolysis during gestation. We evaluated the longitudinal changes in insulin suppression of FFA before pregnancy and in early (12–14 wk) and late (34–36 wk) gestation in obese subjects with normal glucose tolerance and in obese GDM subjects. Abdominal subcutaneous adipose tissue biopsies were also obtained during cesarean delivery from normal obese pregnant (Preg-Con), GDM, and nonpregnant obese control (Non-Preg-Con) subjects during gynecological surgery. GDM subjects had higher basal plasma FFA before pregnancy ( P = 0.055). Insulin's ability to suppress FFA levels declined from early to late gestation in both GDM and Preg-Con subjects and was significantly less in GDM subjects compared with Preg-Con subjects over time ( P = 0.025). Adipose tissue insulin receptor substrate (IRS)-1 protein levels were 43% lower ( P = 0.02) and p85α subunit of phosphatidylinositol 3-kinase was twofold higher ( P = 0.03) in GDM compared with Preg-Con subjects. The levels of peroxisome proliferator-activated receptor-γ (PPARγ) mRNA and protein were lower by 38% in Preg-Con ( P = 0.006) and by 48% in GDM subjects ( P = 0.005) compared with Non-Preg controls. Lipoprotein lipase and fatty acid-binding protein-2 mRNA levels were 73 and 52% lower in GDM compared with Preg-Con subjects ( P < 0.002). Thus GDM women have decreased IRS-1, which may contribute to reduced insulin suppression of lipolysis with advancing gestation. Decreased PPARγ and its target genes may be part of the molecular mechanism to accelerate fat catabolism to meet fetal nutrient demand in late gestation.

scholarly journals The effects of obesity-associated insulin resistance on mRNA expression of peroxisome proliferator-activated receptor-γ target genes, in dogs

2007 ◽  
Vol 98 (3) ◽  
pp. 497-503 ◽  
Author(s):  
Constance Gayet ◽  
Veronique Leray ◽  
Masayuki Saito ◽  
Brigitte Siliart ◽  
Patrick Nguyen
Keyword(s):  
Insulin Resistance ◽  
Skeletal Muscle ◽  
Adipose Tissue ◽  
Insulin Sensitivity ◽  
Mrna Expression ◽  
Target Genes ◽  
Peroxisome Proliferator ◽  
Peroxisome Proliferator Activated Receptor ◽  
Glucose And Lipid Metabolism ◽  
Visceral Adipose

Visceral adipose tissue and skeletal muscle have central roles in determining whole-body insulin sensitivity. The peroxisome proliferator-activated receptor-γ (PPARγ) is a potential mediator of insulin sensitivity. It can directly modulate the expression of genes that are involved in glucose and lipid metabolism, including GLUT4, lipoprotein lipase (LPL) and adipocytokines (leptin and adiponectin). In this study, we aimed to determine the effects of obesity-associated insulin resistance on mRNA expression of PPARγ and its target genes. Dogs were studied when they were lean and at the end of an overfeeding period when they had reached a steady obese state. The use of a sensitive, real-time PCR assay allowed a relative quantification of mRNA expression for PPARγ, LPL, GLUT4, leptin and adiponectin, in adipose tissue and skeletal muscle. In visceral adipose tissue and/or skeletal muscle, mRNA expression of PPARγ, LPL and GLUT4 were at least 2-fold less in obese and insulin-resistant dogs compared with the same animals when they were lean and insulin-sensitive. The mRNA expression and plasma concentration of leptin was increased, whereas the plasma level and mRNA expression of adiponectin was decreased, by obesity. In adipose tissue, PPARγ expression was correlated with leptin and adiponectin. These findings, in an original model of obesity induced by a prolonged period of overfeeding, showed that insulin resistance is associated with a decrease in PPARγ mRNA expression that could dysregulate expression of several genes involved in glucose and lipid metabolism.

scholarly journals Rosiglitazone Increases the Expression of Peroxisome Proliferator-Activated Receptor-γ Target Genes in Adipose Tissue, Liver, and Skeletal Muscle in the Sheep Fetus in Late Gestation

Endocrinology ◽  
2009 ◽  
Vol 150 (9) ◽  
pp. 4287-4294 ◽  
Author(s):  
B. S. Muhlhausler ◽  
J. L. Morrison ◽  
I. C. McMillen
Keyword(s):  
Skeletal Muscle ◽  
Adipose Tissue ◽  
Target Genes ◽  
Fetal Liver ◽  
Late Gestation ◽  
Postnatal Life ◽  
Peroxisome Proliferator ◽  
Peroxisome Proliferator Activated Receptor ◽  
Pparγ Agonist ◽  
Rosiglitazone Treatment

Abstract Exposure to maternal overnutrition increases the expression of peroxisome proliferator-activated receptor-γ (PPARγ) in adipose tissue before birth, and it has been proposed that the precocial activation of PPARγ target genes may lead to increased fat deposition in postnatal life. In this study, we determined the effect of intrafetal administration of a PPARγ agonist, rosiglitazone, on PPARγ target gene expression in fetal adipose tissue as well indirect actions of rosiglitazone on fetal liver and skeletal muscle. Osmotic pumps containing rosiglitazone (n = 7) or vehicle (15% ethanol, n = 7) were implanted into fetuses at 123–126 d gestation (term = 150 ± 3 d gestation). At 137–141 d gestation, tissues were collected and mRNA expression of PPARγ, lipoprotein lipase (LPL), adiponectin, and glycerol-3-phosphate dehydrogenase (G3PDH) in adipose tissue, PPARα and PPARγ-coactivator 1α (PGC1α) in liver and muscle and phosphoenolpyruvate carboxykinase (PEPCK) in liver determined by quantitative real-time RT-PCR. Plasma insulin concentrations were lower in rosiglitazone-treated fetuses (P &lt; 0.02). Rosiglitazone treatment resulted in increased expression of LPL and adiponectin mRNA (P &lt; 0.01) in fetal adipose tissue. The expression of PPARα mRNA in liver (P &lt; 0.05) and PGC1α mRNA (P &lt; 0.02) in skeletal muscle were also increased by rosiglitazone treatment. Rosiglitazone treatment increased expression of PPARγ target genes within fetal adipose tissue and also had direct or indirect actions on the fetal liver and muscle. The effects of activating PPARγ in fetal adipose tissue mimic those induced by prenatal overnutrition, and it is therefore possible that activation of PPARγ may be the initiating mechanism in the pathway from prenatal overnutrition to postnatal obesity.

scholarly journals Extract of Wax Gourd Peel Prevents High-Fat Diet-Induced Hyperlipidemia in C57BL/6 Mice via the Inhibition of the PPARγPathway

2013 ◽  
Vol 2013 ◽  
pp. 1-11 ◽  
Author(s):  
Ming Gu ◽  
Shengjie Fan ◽  
Gaigai Liu ◽  
Lu Guo ◽  
Xiaobo Ding ◽  
...  
Keyword(s):  
Blood Glucose ◽  
High Fat Diet ◽  
Target Genes ◽  
Metabolic Diseases ◽  
Body Weight Gain ◽  
Fasting Blood Glucose ◽  
Peroxisome Proliferator ◽  
Mrna Levels ◽  
High Fat ◽  
Wax Gourd

Wax gourd is a popular vegetable in East Asia. In traditional Chinese medicine, wax gourd peel is used to prevent and treat metabolic diseases such as hyperlipidemia, hyperglycemia, obesity, and cardiovascular disease. However, there is no experimental evidence to support these applications. Here, we examined the effect of the extract of wax gourd peel (EWGP) on metabolic disorders in diet-induced C57BL/6 obese mice. In the preventive experiment, EWGP blocked body weight gain and lowered serum total cholesterol (TC), low-density lipoprotein cholesterol (LDL-c), liver TG and TC contents, and fasting blood glucose in mice fed with a high-fat diet. In the therapeutic study, we induced obesity in the mice and treated with EWGP for two weeks. We found that EWGP treatment reduced serum and liver triglyceride (TG) contents and fasting blood glucose and improved glucose tolerance in the mice. Reporter assay and gene expression analysis showed that EWGP could inhibit peroxisome proliferator-activated receptorγ(PPARγ) transactivities and could decrease mRNA levels of PPARγand its target genes. We also found that HMG-CoA reductase (HMGCR) was downregulated in the mouse liver by EWGP. Our data suggest that EWGP lowers hyperlipidemia of C57BL/6 mice induced by high-fat diet via the inhibition of PPARγand HMGCR signaling.

scholarly journals Adipokines and Metabolic Regulators in Human and Experimental Pulmonary Arterial Hypertension

2021 ◽  
Vol 22 (3) ◽  
pp. 1435
Author(s):  
Aimilia Papathanasiou ◽  
Fotios Spyropoulos ◽  
Zoe Michael ◽  
Kyoung Joung ◽  
Despina Briana ◽  
...  
Keyword(s):  
Pulmonary Hypertension ◽  
Adipose Tissue ◽  
Fatty Acid ◽  
Tricarboxylic Acid Cycle ◽  
Fibroblast Growth Factor 21 ◽  
Mrna Levels ◽  
Rodent Models ◽  
Fatty Acid Binding ◽  
Metabolic Regulators ◽  
Circulating Levels

Pulmonary hypertension (PH) is associated with meta-inflammation related to obesity but the role of adipose tissue in PH pathogenesis is unknown. We hypothesized that adipose tissue-derived metabolic regulators are altered in human and experimental PH. We measured circulating levels of fatty acid binding protein 4 (FABP-4), fibroblast growth factor -21 (FGF-21), adiponectin, and the mRNA levels of FABP-4, FGF-21, and peroxisome proliferator-activated receptor γ (PPARγ) in lung tissue of patients with idiopathic PH and healthy controls. We also evaluated lung and adipose tissue expression of these mediators in the three most commonly used experimental rodent models of pulmonary hypertension. Circulating levels of FABP-4, FGF-21, and adiponectin were significantly elevated in PH patients compared to controls and the mRNA levels of these regulators and PPARγ were also significantly increased in human PH lungs and in the lungs of rats with experimental PH compared to controls. These findings were coupled with increased levels of adipose tissue mRNA of genes related to glucose uptake, glycolysis, tricarboxylic acid cycle, and fatty acid oxidation in experimental PH. Our results support that metabolic alterations in human PH are recapitulated in rodent models of the disease and suggest that adipose tissue may contribute to PH pathogenesis.

Cellular Mechanisms for Insulin Resistance in Normal Pregnancy and Gestational Diabetes

Diabetes Care ◽  
2007 ◽  
Vol 30 (Supplement 2) ◽  
pp. S112-S119 ◽  
Author(s):  
L. A. Barbour ◽  
C. E. McCurdy ◽  
T. L. Hernandez ◽  
J. P. Kirwan ◽  
P. M. Catalano ◽  
...  
Keyword(s):  
Insulin Resistance ◽  
Gestational Diabetes ◽  
Normal Pregnancy ◽  
Cellular Mechanisms

scholarly journals Complement Factor C3 Methylation and mRNA Expression Is Associated to BMI and Insulin Resistance in Obesity

Genes ◽  
2018 ◽  
Vol 9 (8) ◽  
pp. 410 ◽  
Author(s):  
Daniel Castellano-Castillo ◽  
Isabel Moreno-Indias ◽  
Jose Carlos Fernandez-Garcia ◽  
Mercedes Clemente-Postigo ◽  
Manuel Castro-Cabezas ◽  
...  
Keyword(s):  
Insulin Resistance ◽  
Dna Methylation ◽  
Adipose Tissue ◽  
Messenger Rna ◽  
Density Lipoprotein ◽  
Complement Factor ◽  
Mrna Levels ◽  
Model Assessment ◽  
Tissue Samples ◽  
Obese Class

Epigenetic marks, and especially DNA methylation, are becoming an important factor in obesity, which could help to explain its etiology and associated comorbidities. Adipose tissue, now considered as an important endocrine organ, produces complement system factors. Complement component 3 (C3) turns out to be an important protein in metabolic disorders, via either inflammation or the C3 subproduct acylation stimulating protein (ASP) which directly stimulates lipid storage. In this study, we analyze C3 DNA methylation in adipose tissue from subjects with a different grade of obesity. Adipose tissue samples were collected from subjects with a different degree of obesity determined by their body mass index (BMI) as: Overweight subjects (BMI ≥ 25 and <30), obese class 1/2 subjects (BMI ≥ 30 and <40) and obese class 3 subjects (BMI ≥ 40). C3 DNA methylation was measured for 7 CpGs by pyrosequencition using the Pyromark technology (Qiagen, Madrid Spain). C3 messenger RNA (mRNA) levels were analyzed by pre-designed Taqman assays (Applied biosystems, Foster City, CA, USA) and ASP/C3a was measured using a ELISA kit. The data were analyzed using the statistic package SPSS. C3 DNA methylation levels were lower in the morbid obese group. Accordingly, C3 methylation correlated negatively with BMI and leptin. However, C3 mRNA levels were more associated with insulin resistance, and positive correlations with insulin, glucose and homeostasis model assessment-estimated insulin resistance (HOMA-IR) existed. ASP correlated negatively with high density lipoprotein (HDL) cholesterol. C3 methylation levels were associated to adiposity variables, such as BMI and leptin, while the C3 mRNA levels were associated to glucose metabolism.

Clofibrate causes an upregulation of PPAR-α target genes but does not alter expression of SREBP target genes in liver and adipose tissue of pigs

2007 ◽  
Vol 293 (1) ◽  
pp. R70-R77 ◽  
Author(s):  
Sebastian Luci ◽  
Beatrice Giemsa ◽  
Holger Kluge ◽  
Klaus Eder
Keyword(s):  
Adipose Tissue ◽  
Target Genes ◽  
Regulatory Element ◽  
Control Diet ◽  
Low Density Lipoprotein ◽  
Density Lipoprotein ◽  
Cholesterol Homeostasis ◽  
Peroxisome Proliferator ◽  
Peroxisome Proliferator Activated Receptor ◽  
Hepatic Expression

This study investigated the effect of clofibrate treatment on expression of target genes of peroxisome proliferator-activated receptor (PPAR)-α and various genes of the lipid metabolism in liver and adipose tissue of pigs. An experiment with 18 pigs was performed in which pigs were fed either a control diet or the same diet supplemented with 5 g clofibrate/kg for 28 days. Pigs treated with clofibrate had heavier livers, moderately increased mRNA concentrations of various PPAR-α target genes in liver and adipose tissue, a higher concentration of 3-hydroxybutyrate, and markedly lower concentrations of triglycerides and cholesterol in plasma and lipoproteins than control pigs ( P < 0.05). mRNA concentrations of sterol regulatory element-binding proteins (SREBP)-1 and -2, insulin-induced genes ( Insig) -1 and Insig-2, and the SREBP target genes acetyl-CoA carboxylase, 3-methyl-3-hydroxyglutaryl-CoA reductase, and low-density lipoprotein receptor in liver and adipose tissue and mRNA concentrations of apolipoproteins A-I, A-II, and C-III in the liver were not different between both groups of pigs. In conclusion, this study shows that clofibrate treatment activates PPAR-α in liver and adipose tissue and has a strong hypotriglyceridemic and hypocholesterolemic effect in pigs. The finding that mRNA concentrations of some proteins responsible for the hypolipidemic action of fibrates in humans were not altered suggests that there were certain differences in the mode of action compared with humans. It is also shown that PPAR-α activation by clofibrate does not affect hepatic expression of SREBP target genes involved in synthesis of triglycerides and cholesterol homeostasis in liver and adipose tissue of pigs.

scholarly journals FABP4-Cre Mediated Expression of Constitutively Active ChREBP Protects Against Obesity, Fatty Liver, and Insulin Resistance

Endocrinology ◽  
2015 ◽  
Vol 156 (11) ◽  
pp. 4020-4032 ◽  
Author(s):  
Alli M. Nuotio-Antar ◽  
Naravat Poungvarin ◽  
Ming Li ◽  
Michael Schupp ◽  
Mahmoud Mohammad ◽  
...  
Keyword(s):  
Insulin Resistance ◽  
Adipose Tissue ◽  
Fatty Liver ◽  
Binding Protein ◽  
Western Diet ◽  
Whole Body ◽  
Lipid Homeostasis ◽  
Chow Diet ◽  
Fatty Acid Binding ◽  
Constitutively Active

Carbohydrate response element binding protein (ChREBP) regulates cellular glucose and lipid homeostasis. Although ChREBP is highly expressed in many key metabolic tissues, the role of ChREBP in most of those tissues and the consequent effects on whole-body glucose and lipid metabolism are not well understood. Therefore, we generated a transgenic mouse that overexpresses a constitutively active ChREBP isoform under the control of the fatty acid binding protein 4-Cre-driven promoter (FaChOX). Weight gain was blunted in male, but not female, FaChOX mice when placed on either a normal chow diet or an obesogenic Western diet. Respiratory exchange ratios were increased in Western diet-fed FaChOX mice, indicating a shift in whole-body substrate use favoring carbohydrate metabolism. Western diet-fed FaChOX mice showed improved insulin sensitivity and glucose tolerance in comparison with controls. Hepatic triglyceride content was reduced in Western diet-fed FaChOX mice in comparison with controls, suggesting protection from fatty liver. Epididymal adipose tissue exhibited differential expression of genes involved in differentiation, browning, metabolism, lipid homeostasis, and inflammation between Western diet-fed FaChOX mice and controls. Our findings support a role for ChREBP in modulating adipocyte differentiation and adipose tissue metabolism and inflammation as well as consequent risks for obesity and insulin resistance.

Sign in / Sign up

Export Citation Format

Share Document