scholarly journals Genetic and Pharmacological Inhibition of PAPP-A Protects Against Visceral Obesity in Mice

Endocrinology ◽  
2020 ◽  
Vol 161 (10) ◽  
Author(s):  
Akhila Ramakrishna ◽  
Laurie K Bale ◽  
Sally A West ◽  
Cheryl A Conover
Keyword(s):  
Gene Expression ◽  
Adipose Tissue ◽  
Liver Lipid ◽  
Protein A ◽  
Visceral Obesity ◽  
Cell Number ◽  
Metabolic Effects ◽  
Adipocyte Size ◽  
Fat Depots ◽  
Mesenteric Fat

Abstract Pathogenicity of visceral adipose tissue (VAT) has been linked to the metabolic stress of enlarging mature adipocytes and a limited ability to recruit new adipocytes. One of the major distinguishing features of VAT preadipocytes is the high expression of the zinc metalloprotease, pregnancy-associated plasma protein-A (PAPP-A), when compared to subcutaneous adipose tissue (SAT). In this study we used 2 different approaches to investigate the effect of PAPP-A inhibition on different fat depots in mice on a high-fat diet (HFD) for 15 weeks. Conditional knockdown of PAPP-A gene expression in female adult mice resulted in significant decreases of 30% to 40% in adipocyte size in VAT (mesenteric and pericardial depots) compared to control mice. There was no effect on SAT (inguinal) or intra-abdominal perigonadal fat. Liver lipid was also significantly decreased without any effect on heart and skeletal muscle lipid. We found similar effects when using a pharmacological approach. Weekly injections of a specific immunoneutralizing monoclonal antibody (mAb-PA 1/41) or isotype control were given to male and female wild-type mice on HFD for 15 weeks. Adipocyte size was significantly decreased (30%-50%) only in VAT with mAb-PA 1/41 treatment. In this model, cell number was significantly increased in mesenteric fat in mice treated with mAb-PA 1/41, suggesting hyperplasia along with reduced hypertrophy in this VAT depot. Gene expression data indicated a significant decrease in F4/80 (macrophage marker) and interleukin-6 (proinflammatory cytokine) and a significant increase in adiponectin (anti-inflammatory adipokine with beneficial metabolic effects) in mesenteric fat compared to inguinal fat in mice treated with mAb-PA 1/41. Furthermore, there was significantly decreased liver lipid content with mAb-PA 1/41 treatment. Thus, using 2 different models systems we provide proof of principle that PAPP-A inhibition is a potential therapeutic target to prevent visceral obesity and its metabolic sequelae, such as fatty liver.

Abstract 6260: Up-Regulated Expression of MicroRNA-143 in Association with Obesity in the Adipose Tissue of Mice Fed High Fat Diet

Circulation ◽  
2008 ◽  
Vol 118 (suppl_18) ◽  
Author(s):  
Rieko Takanabe ◽  
Koh Ono ◽  
Tomohide Takaya ◽  
Takahiro Horie ◽  
Hiromichi Wada ◽  
...  
Keyword(s):  
Gene Expression ◽  
Insulin Resistance ◽  
Body Weight ◽  
Adipose Tissue ◽  
High Fat Diet ◽  
Control Cell ◽  
High Fat ◽  
Expression Levels ◽  
Mesenteric Fat ◽  
Regulated Expression

Obesity is the result of an expansion and increase in the number of individual adipocytes. Since changes in gene expression during adipocyte differentiation and hypertrophy are closely associated with insulin resistance and cardiovascular diseases, further insight into the molecular basis of obesity is needed to better understand obesity-associated diseases. MicroRNAs (miRNAs) are approximately 17–24nt single stranded RNA, that post-transcriptionally regulate gene expression. MiRNAs control cell growth, differentiation and metabolism, and may be also involved in pathogenesis and pathophysiology of diseases. It has been proposed that miR-143 plays a role in the differentiation of preadipocytes into mature adipocytes in culture. However, regulated expression of miR-143 in the adult adipose tissue during the development of obesity in vivo is unknown. To solve this problem, C57BL/6 mice were fed with either high-fat diet (HFD) or normal chow (NC). Eight weeks later, severe insulin resistance was observed in mice on HFD. Body weight increased by 35% and the mesenteric fat weight increased by 3.3-fold in HFD mice compared with NC mice. We measured expression levels of miR-143 in the mesenteric fat tissue by real-time PCR and normalized with those of 5S ribosomal RNA. Expression of miR-143 in the mesenteric fat was significantly up-regulated (3.3-fold, p<0.05) in HFD mice compared to NC mice. MiR-143 expression levels were positively correlated with body weight (R=0.577, p=0.0011) and the mesenteric fat weight (R=0.608, p=0.0005). We also measured expression levels in the mesenteric fat of PPARγ and AP2, whose expression are deeply involved in the development of obesity, insulin resistant and arteriosclerosis. The expression levels of miR-143 were closely correlated with those of PPARγ (R=0.600, p=0.0040) and AP2 (R=0.630, p=0.0022). These findings provide the first evidence for up-regulated expression of miR-143 in the mesenteric fat of HFD-induced obese mice, which might contribute to regulated expression of genes involved in the pathophysiology of obesity.

scholarly journals Expression of adipocytokine genes and their content in various adipose tissue sites in patients with heart diseases

2020 ◽  
Author(s):  
Olga Gruzdeva ◽  
Yulia Dyleva ◽  
Ekaterina Belik ◽  
Daria Borodkina ◽  
Maxim Sinitsky ◽  
...  
Keyword(s):  
Gene Expression ◽  
Coronary Artery Disease ◽  
Adipose Tissue ◽  
Coronary Artery ◽  
Mitral Valve ◽  
Valve Replacement ◽  
Mitral Valve Replacement ◽  
Biologically Active ◽  
Fat Depots ◽  
Artery Disease

Abstract Background Adipose tissue (AT) is an endocrine and paracrine organ that synthesizes biologically active adipocytokines, which affect inflammation, fibrosis, and atherogenesis. Epicardial and perivascular fat depots are of great interest owing to potential effects on the myocardium and blood vessels. Objective To assess expression and secretion of adipocytokine genes in adipose tissue in patients coronary artery disease (CAD) and patients with aortic or mitral valve replacement. Methods The study included 84 patients with CAD and 50 patients with aortic or mitral valve replacement. Adipocytes were isolated from subcutaneous (SAT), epicardial (EAT), and perivascular AT (PVAT) samples. Isolated adipocytes were cultured for 24 h after which, gene expression and secretion levels of selected adipokines and cytokines in the culture medium were determined. Results The study parameters differed depending on the adipose tissue location. EAT adipocytes in CAD patients were characterized by a pronounced imbalance in the adipokine system. EAT had the lowest adiponectin gene expression and secretion, regardless of nosology and high expression levels of the leptin gene, its receptor, and interleukin-6 (IL-6) were detected. High leptin and IL-6 levels resulted in increased pro-inflammatory activity, as observed in both EAT and PVAT adipocytes, especially in individuals with coronary artery disease. Conclusion The "protective" potential of adipose tissue depends on its location.

STUDIES ON THE NUMBER AND VOLUME OF FAT CELLS IN ADIPOSE TISSUE

1962 ◽  
Vol 40 (1) ◽  
pp. 437-442 ◽  
Author(s):  
W. Zingg ◽  
A. Angel ◽  
M. D. Steinberg
Keyword(s):  
Adipose Tissue ◽  
Cell Volume ◽  
Histological Examination ◽  
Cell Number ◽  
Fat Content ◽  
Fat Cells ◽  
Desoxyribonucleic Acid ◽  
Fat Depots ◽  
Perirenal Fat

The changes in number and volume of fat cells accompanying changes in the size of the perirenal fat depots of rats induced by dietary and other means have been investigated by direct histological examination and by estimation of the total desoxyribonucleic acid (DNA) and fat content. With both methods, an increase in cell volume and in cell number was found to accompany an increase in depot volume.

Mechanism of enhanced lipolysis in adipose tissue of exercise-trained rats

1980 ◽  
Vol 239 (6) ◽  
pp. E422-E429 ◽  
Author(s):  
L. Bukowiecki ◽  
J. Lupien ◽  
N. Follea ◽  
A. Paradis ◽  
D. Richard ◽  
...  
Keyword(s):  
Adipose Tissue ◽  
Exercise Training ◽  
Food Restriction ◽  
Female Rats ◽  
Epididymal Adipose Tissue ◽  
Adipocyte Size ◽  
Fat Depots ◽  
Male And Female Rats ◽  
Receptor Sites ◽  
Stimulus Recognition

The effects of exercise training and food restriction on the regulation of lipolysis were studied comparatively in adipocytes isolated from male and female rats. Exercise training inhibited cell proliferation in parametrial, but not in epididymal adipose tissue, whereas it significantly reduced adipocyte size in both fat depots. Adipocyte capacity for responding lipolytically to epinephrine (10 microns) or to ACTH (1 micron) was markedly increased by exercise training. Enhanced lipolysis was also observed when cells isolated from exercise-trained animals were stimulated by bypassing with dibutyryl cyclic AMP (5 mM) or theophylline (5 mM) the early metabolic steps associated with hormonal activation of the adenylate cyclase complex. Significantly, binding of (-)-[3H]dihydroalprenolol to cellular receptor sites was not affected by exercise training. It is therefore concluded that exercise training increases adipocyte responsiveness to lipolytic hormones at a metabolic step distal to stimulus recognition by adrenoreceptors, possibly at the level of protein kinases or lipases. Food restriction markedly reduced adipocyte size and partially mimicked the effects of exercise training on adipocyte proliferation and lipolysis.

Ultrasonographic measurement of liver, portal vein, hepatic vein and perivisceral adipose tissue in high-yielding dairy cows with fatty liver during the transition period

2018 ◽  
Vol 85 (4) ◽  
pp. 431-438 ◽  
Author(s):  
Enrico Fiore ◽  
Laura Perillo ◽  
Massimo Morgante ◽  
Elisabetta Giudice ◽  
Barbara Contiero ◽  
...  
Keyword(s):  
Adipose Tissue ◽  
Fatty Liver ◽  
Dairy Cows ◽  
Transition Period ◽  
Body Condition Score ◽  
Liver Lipid ◽  
Perivascular Adipose Tissue ◽  
Liver Lipid Content ◽  
Mesenteric Fat ◽  
Condition Score

The aim of the present study was to evaluate the potential for diagnosis of fatty liver by means of ultrasonographic measurement of liver and perivisceral adipose tissue as an alternative to blood indicators of lipomobilization and liver biopsy in periparturient high-yielding dairy cows. Thirty cows were enrolled and divided into two groups. The evaluation of body condition score (BCS), non-esterified fatty acids (NEFA), β-hydroxybutyrate (BHB), liver and perivisceral adipose tissue ultrasonographic measurement and histological liver lipid content (GdL) was performed at 15 ± 5 d prepartum (T0), 10 ± 2 d postpartum (T1), 30 ± 2 d postpartum (T2) and 50 ± 2 d postpartum (T3). Mesenteric fat thickness (the thickness of the perivascular adipose tissue) measured on ultrasound was shown to be an independent determinant of fatty liver. The cut-off of the ultrasonographic evaluation of the liver may be useful as a first and practical approach in identifying fatty liver. In conclusion, a non-invasive and reliable diagnostic method for predicting the risk of fatty liver in high yielding dairy cows has been demonstrated.

scholarly journals Peripancreatic adipose tissue protects against high-fat-diet-induced hepatic steatosis and insulin resistance in mice

2020 ◽  
Vol 44 (11) ◽  
pp. 2323-2334
Author(s):  
Belén Chanclón ◽  
Yanling Wu ◽  
Milica Vujičić ◽  
Marco Bauzá-Thorbrügge ◽  
Elin Banke ◽  
...  
Keyword(s):  
Gene Expression ◽  
Insulin Resistance ◽  
Adipose Tissue ◽  
Hepatic Steatosis ◽  
High Fat Diet ◽  
Obese Mice ◽  
High Fat ◽  
Insulin Levels ◽  
Fat Depots ◽  
Fat Depot

Abstract Background/objectives Visceral adiposity is associated with increased diabetes risk, while expansion of subcutaneous adipose tissue may be protective. However, the visceral compartment contains different fat depots. Peripancreatic adipose tissue (PAT) is an understudied visceral fat depot. Here, we aimed to define PAT functionality in lean and high-fat-diet (HFD)-induced obese mice. Subjects/methods Four adipose tissue depots (inguinal, mesenteric, gonadal, and peripancreatic adipose tissue) from chow- and HFD-fed male mice were compared with respect to adipocyte size (n = 4–5/group), cellular composition (FACS analysis, n = 5–6/group), lipogenesis and lipolysis (n = 3/group), and gene expression (n = 6–10/group). Radioactive tracers were used to compare lipid and glucose metabolism between these four fat depots in vivo (n = 5–11/group). To determine the role of PAT in obesity-associated metabolic disturbances, PAT was surgically removed prior to challenging the mice with HFD. PAT-ectomized mice were compared to sham controls with respect to glucose tolerance, basal and glucose-stimulated insulin levels, hepatic and pancreatic steatosis, and gene expression (n = 8–10/group). Results We found that PAT is a tiny fat depot (~0.2% of the total fat mass) containing relatively small adipocytes and many “non-adipocytes” such as leukocytes and fibroblasts. PAT was distinguished from the other fat depots by increased glucose uptake and increased fatty acid oxidation in both lean and obese mice. Moreover, PAT was the only fat depot where the tissue weight correlated positively with liver weight in obese mice (R = 0.65; p = 0.009). Surgical removal of PAT followed by 16-week HFD feeding was associated with aggravated hepatic steatosis (p = 0.008) and higher basal (p < 0.05) and glucose-stimulated insulin levels (p < 0.01). PAT removal also led to enlarged pancreatic islets and increased pancreatic expression of markers of glucose-stimulated insulin secretion and islet development (p < 0.05). Conclusions PAT is a small metabolically highly active fat depot that plays a previously unrecognized role in the pathogenesis of hepatic steatosis and insulin resistance in advanced obesity.

scholarly journals Changes in adipose tissue physiology during the first two weeks posthatch in chicks from lines selected for low or high body weight

2019 ◽  
Vol 316 (6) ◽  
pp. R802-R818 ◽  
Author(s):  
Yang Xiao ◽  
Guoqing Wang ◽  
Miranda E. Gerrard ◽  
Sarah Wieland ◽  
Mary Davis ◽  
...  
Keyword(s):  
Body Weight ◽  
Adipose Tissue ◽  
Fat Mass ◽  
Peroxisome Proliferator ◽  
Adipocyte Size ◽  
Peroxisome Proliferator Activated Receptor ◽  
Nonesterified Fatty Acids ◽  
Development Patterns ◽  
Fat Depots ◽  
Enhancer Binding Protein

Chickens from lines selected for low (LWS) or high (HWS) body weight (BW) differ in appetite and adiposity. Mechanisms associated with the predisposition to becoming obese are unclear. The objective of the experiment was to evaluate developmental changes in depot-specific adipose tissue during the first 2 wk posthatch. Subcutaneous (SQ), clavicular (CL), and abdominal (AB) depots were collected at hatch (DOH) and days 4 (D4) and 14 (D14) posthatch for histological and mRNA measurements. LWS chicks had decreased SQ fat mass on a BW basis with reduced adipocyte size from DOH to D4 and increased BW and fat mass with unchanged adipocyte size from D4 to D14. HWS chicks increased in BW from DOH to D14 and increased in fat mass in all three depots with enlarged adipocytes in the AB depot from D4 to D14. Meanwhile, CCAAT/enhancer-binding protein-α, neuropeptide Y, peroxisome proliferator-activated receptor-γ, and acyl-CoA dehydrogenase mRNAs differed among depots between lines at different ages. Plasma nonesterified fatty acids were greater in LWS than HWS at D4 and D14. From DOH to D4, LWS chicks mobilized SQ fat and replenished the reservoir through hyperplasia, whereas HWS chicks were dependent on hyperplasia and hypertrophy to maintain adipocyte size and depot mass. From D4 to D14, adipose tissue catabolism and adipogenesis slowed. Whereas LWS fat depots and adipocyte sizes remained stable, HWS chicks rapidly accumulated fat in CL and AB depots. Chicks predisposed to be anorexic or obese have different fat development patterns during the first 2 wk posthatch.

scholarly journals Thermoneutrality Reduces the Beneficial Metabolic Effects of Eicosapentaenoic Acid on White Adipose Tissue in Diet-Induced Obese Mice

2020 ◽  
Vol 4 (Supplement_2) ◽  
pp. 1254-1254
Author(s):  
Bimba Goonapienuwala ◽  
Mandana Pahlavani ◽  
Latha Ramalingam ◽  
Kembra Albracht-Schulte ◽  
William Festuccia ◽  
...  
Keyword(s):  
Adipose Tissue ◽  
Glucose Tolerance ◽  
Eicosapentaenoic Acid ◽  
Uncoupling Protein ◽  
Serum Triglyceride ◽  
Metabolic Effects ◽  
Omega 3 ◽  
Adipocyte Size ◽  
Mitochondrial Energy Metabolism ◽  
Significant Difference

Abstract Objectives At ambient temperature (23°C), eicosapentaenoic acid (EPA), an omega-3 polyunsaturated fatty acid reduces visceral adipose tissue (VAT) inflammation, adipocyte size and improves overall metabolic profile in diet-induced obese (DIO) mice, potentially through upregulation of uncoupling protein 1 (UCP-1). The goal of this study is to determine whether effects of EPA are maintained at thermoneutrality, and/or mediated by UCP-1, and if so through which cellular mechanisms. Methods Wild type (WT) and UCP-1 knockout (KO) B6 male mice were housed at thermoneutral temperature (28–30°C) and fed high fat (HF, 45% kcal fat) supplemented with or without EPA (36 g/kg diet). Serum, VAT (epididymal fat) and cecal microbiome specimens were analyzed. Results EPA reduced adiposity and improved glucose tolerance in EPA-fed KO mice (P &lt; 0.05), but not in EPA-fed WT mice. EPA supplementation lowered VAT mass in both genotypes (P &lt; 0.05); however, there were no diet or genotype-related differences in adipocyte size or serum triglyceride levels. Both genotypes fed EPA had lower serum resistin levels compared to respective HF (P &lt; 0.01). EPA showed trends towards increased serum adiponectin levels compared to HF fed mice in both genotypes, with KO-EPA group having the highest concentration. There was no significant difference in the expression of IL-6 in VAT among the groups, while MCP-1 mRNA was expressed more in KO groups compared to WT groups (P &lt; 0.01). Diet had no effect on expression of anti-inflammatory markers in both WT and KO mice. There were no genotype or diet effects on expression of genes involved in lipid metabolism and mitochondrial energy metabolism. Cecal microbiome showed no differences in the species diversity (Shannon index) between genotypes or diet types. However, only in the KO group, the Bacteroidetes/Firmicutes ratio was increased by EPA. Conclusions Compared to previous work at ambient temperatures, VAT does not mediate protective effects of EPA in DIO mice at thermoneutral temperature. Moreover, EPA effects are independent of UCP-1 as it produced beneficial effects on glucose tolerance and adiposity in KO mice, which may be in part mediated by changes in microbiome. Further mechanistic studies are ongoing to understand the mechanisms mediating EPA and UCP-1 effects in VAT. Funding Sources Funded by NIH (NCCIH and NIA).

Diet-induced adipocyte number increase in adult rats: a new model of obesity.

1978 ◽  
Vol 235 (3) ◽  
pp. E279 ◽  
Author(s):  
I M Faust ◽  
P R Johnson ◽  
J S Stern ◽  
J Hirsch
Keyword(s):  
Adipose Tissue ◽  
Weight Gain ◽  
Cell Number ◽  
Chow Diet ◽  
Adipocyte Size ◽  
Adult Rats ◽  
Tissue Morphology ◽  
Number Increase ◽  
Dietary Obesity ◽  
Morphology Changes

Adult rats of various strains became obese when they were fed a highly palatable diet for several months. Analysis of their adipose tissue morphology revealed increases in both adipocyte size and number in most depots. Reintroduction of an ordinary chow diet to such animals precipitated a period of weight loss during which only mean adipocyte size returned to normal. Adipocyte number remained at the elevated level achieved during the period of weight gain. Thus, transient dietary obesity in rats results in a persistent obesity of a purely hyperplastic, nonhypertrophic form. Furthermore, the persistence of the cell number increase suggests that it is the result of proliferation or differentiation rather than of only an increase in the lipid content of a pool of very small and normally undetected adipocytes. An analysis of adipose tissue morphology changes during the course of diet-induced weight gain suggests that the achievement of some specific mean adipocyte size triggers the events that culminate in adipocyte number increase. What mechanisms may link adipocyte size to the formation of new adipocytes remains unknown.

scholarly journals Characterization of the inflammatory and metabolic profile of adipose tissue in a mouse model of chronic hypoxia

2013 ◽  
Vol 114 (11) ◽  
pp. 1619-1628 ◽  
Author(s):  
Bram van den Borst ◽  
Annemie M. W. J. Schols ◽  
Chiel de Theije ◽  
Agnes W. Boots ◽  
S. Eleonore Köhler ◽  
...  
Keyword(s):  
Gene Expression ◽  
Body Weight ◽  
Adipose Tissue ◽  
Food Intake ◽  
Metabolic Profile ◽  
Chronic Hypoxia ◽  
Chronic Obstructive ◽  
Adipocyte Size ◽  
Metabolic Complications ◽  
Macrophage Density

In both obesity and chronic obstructive pulmonary disease (COPD), altered oxygen tension in adipose tissue (AT) has been suggested to evoke AT dysfunction, subsequently contributing to metabolic complications. Studying the effects of chronic hypoxia on AT function will add to our understanding of the complex pathophysiology of alterations in AT inflammation, metabolism, and mass observed in both obesity and COPD. This study investigated the inflammatory and metabolic profile of AT after chronic hypoxia. Fifty-two-week-old C57Bl/6J mice were exposed to chronic hypoxia (8% O2) or normoxia for 21 days, after which AT and plasma were collected. Adipocyte size, AT gene expression of inflammatory and metabolic genes, AT macrophage density, and circulating adipokine concentrations were measured. Food intake and body weight decreased upon initiation of hypoxia. However, whereas food intake normalized after 10 days, lower body weight persisted. Chronic hypoxia markedly reduced AT mass and adipocyte size. AT macrophage density and expression of Emr1, Ccl2, Lep, and Tnf were decreased, whereas Serpine1 and Adipoq expression levels were increased after chronic hypoxia. Concomitantly, chronic hypoxia increased AT expression of regulators of oxidative metabolism and markers of mitochondrial function and lipolysis. Circulating IL-6 and PAI-1 concentrations were increased, and leptin concentration was decreased after chronic hypoxia. Chronic hypoxia is associated with decreased rather than increased AT inflammation, and markedly decreased fat mass and adipocyte size. Furthermore, our data indicate that chronic hypoxia is accompanied by significant alterations in AT metabolic gene expression, pointing toward an enhanced AT metabolic rate.

Sign in / Sign up

Export Citation Format

Share Document