Downregulation of Adipose Tissue Fatty Acid Trafficking in Obesity

PubMed Central

McQuaid, Siobhán E.; Hodson, Leanne; Neville, Matthew J.; Dennis, A. Louise; Cheeseman, Jane; Humphreys, Sandy M.; Ruge, Toralph; Gilbert, Marjorie; Fielding, Barbara A.; Frayn, Keith N.; Karpe, Fredrik

2011-01-01

OBJECTIVE Lipotoxicity and ectopic fat deposition reduce insulin signaling. It is not clear whether excess fat deposition in nonadipose tissue arises from excessive fatty acid delivery from adipose tissue or from impaired adipose tissue storage of ingested fat. RESEARCH DESIGN AND METHODS To investigate this we used a whole-body integrative physiological approach with multiple and simultaneous stable-isotope fatty acid tracers to assess delivery and transport of endogenous and exogenous fatty acid in adipose tissue over a diurnal cycle in lean (n = 9) and abdominally obese men (n = 10). RESULTS Abdominally obese men had substantially (2.5-fold) greater adipose tissue mass than lean control subjects, but the rates of delivery of nonesterified fatty acids (NEFA) were downregulated, resulting in normal systemic NEFA concentrations over a 24-h period. However, adipose tissue fat storage after meals was substantially depressed in the obese men. This was especially so for chylomicron-derived fatty acids, representing the direct storage pathway for dietary fat. Adipose tissue from the obese men showed a transcriptional signature consistent with this impaired fat storage function. CONCLUSIONS Enlargement of adipose tissue mass leads to an appropriate downregulation of systemic NEFA delivery with maintained plasma NEFA concentrations. However the implicit reduction in adipose tissue fatty acid uptake goes beyond this and shows a maladaptive response with a severely impaired pathway for direct dietary fat storage. This adipose tissue response to obesity may provide the pathophysiological basis for ectopic fat deposition and lipotoxicity. PMID:20943748

Comparison of Dorsocervical With Abdominal Subcutaneous Adipose Tissue in Patients With and Without Antiretroviral Therapy–Associated Lipodystrophy

PubMed Central

Sevastianova, Ksenia; Sutinen, Jussi; Greco, Dario; Sievers, Meline; Salmenkivi, Kaisa; Perttilä, Julia; Olkkonen, Vesa M.; Wågsäter, Dick; Lidell, Martin E.; Enerbäck, Sven; Eriksson, Per; Walker, Ulrich A.; Auvinen, Petri; Ristola, Matti; Yki-Järvinen, Hannele

2011-01-01

OBJECTIVE Combination antiretroviral therapy (cART) is associated with lipodystrophy, i.e., loss of subcutaneous adipose tissue in the abdomen, limbs, and face and its accumulation intra-abdominally. No fat is lost dorsocervically and it can even accumulate in this region (buffalo hump). It is unknown how preserved dorsocervical fat differs from abdominal subcutaneous fat in HIV-1–infected cART-treated patients with (cART+LD+) and without (cART+LD−) lipodystrophy. RESEARCH DESIGN AND METHODS We used histology, microarray, PCR, and magnetic resonance imaging to compare dorsocervical and abdominal subcutaneous adipose tissue in cART+LD+ (n = 21) and cART+LD− (n = 11). RESULTS Albeit dorsocervical adipose tissue in cART+LD+ seems spared from lipoatrophy, its mitochondrial DNA (mtDNA; copies/cell) content was significantly lower (by 62%) than that of the corresponding tissue in cART+LD−. Expression of CD68 mRNA, a marker of macrophages, and numerous inflammatory genes in microarray were significantly lower in dorsocervical versus abdominal subcutaneous adipose tissue. Genes with the greatest difference in expression between the two depots were those involved in regulation of transcription and regionalization (homeobox genes), irrespective of lipodystrophy status. There was negligible mRNA expression of uncoupling protein 1, a gene characteristic of brown adipose tissue, in either depot. CONCLUSIONS Because mtDNA is depleted even in the nonatrophic dorsocervical adipose tissue, it is unlikely that the cause of lipoatrophy is loss of mtDNA. Dorsocervical adipose tissue is less inflamed than lipoatrophic adipose tissue. It does not resemble brown adipose tissue. The greatest difference in gene expression between dorsocervical and abdominal subcutaneous adipose tissue is in expression of homeobox genes. PMID:21602514

Adipose Tissue Plasticity During Catch-Up Fat Driven by Thrifty Metabolism

PubMed Central

Summermatter, Serge; Marcelino, Helena; Arsenijevic, Denis; Buchala, Antony; Aprikian, Olivier; Assimacopoulos-Jeannet, Françoise; Seydoux, Josiane; Montani, Jean-Pierre; Solinas, Giovanni; Dulloo, Abdul G.

2009-01-01

OBJECTIVE Catch-up growth, a risk factor for later type 2 diabetes, is characterized by hyperinsulinemia, accelerated body-fat recovery (catch-up fat), and enhanced glucose utilization in adipose tissue. Our objective was to characterize the determinants of enhanced glucose utilization in adipose tissue during catch-up fat. RESEARCH DESIGN AND METHODS White adipose tissue morphometry, lipogenic capacity, fatty acid composition, insulin signaling, in vivo glucose homeostasis, and insulinemic response to glucose were assessed in a rat model of semistarvation-refeeding. This model is characterized by glucose redistribution from skeletal muscle to adipose tissue during catch-up fat that results solely from suppressed thermogenesis (i.e., without hyperphagia). RESULTS Adipose tissue recovery during the dynamic phase of catch-up fat is accompanied by increased adipocyte number with smaller diameter, increased expression of genes for adipogenesis and de novo lipogenesis, increased fatty acid synthase activity, increased proportion of saturated fatty acids in triglyceride (storage) fraction but not in phospholipid (membrane) fraction, and no impairment in insulin signaling. Furthermore, it is shown that hyperinsulinemia and enhanced adipose tissue de novo lipogenesis occur concomitantly and are very early events in catch-up fat. CONCLUSIONS These findings suggest that increased adipose tissue insulin stimulation and consequential increase in intracellular glucose flux play an important role in initiating catch-up fat. Once activated, the machinery for lipogenesis and adipogenesis contribute to sustain an increased insulin-stimulated glucose flux toward fat storage. Such adipose tissue plasticity could play an active role in the thrifty metabolism that underlies glucose redistribution from skeletal muscle to adipose tissue. PMID:19602538

Is epicardial adipose tissue, assessed by echocardiography, a reliable method for visceral adipose tissue prediction?

PubMed

Silaghi, Alina Cristina; Poantă, Laura; Valea, Ana; Pais, Raluca; Silaghi, Horatiu

2011-03-01

Epicardial adipose tissue is an ectopic fat storage at the heart surface in direct contact with the coronary arteries. It is considered a metabolically active tissue, being a local source of pro-inflammatory factors that contribute to the pathogenesis of coronary artery disease. The AIM of our study was to establish correlations between echocardiographic assessment of epicardial adipose tissue and anthropometric and ultrasound measurements of the central and peripheral fat depots. The study was conducted on 22 patients with or without coronaropathy. Epicardial adipose tissue was measured using Aloka Prosound α 10 machine with a 3.5-7.5 MHz variable-frequency transducer and subcutaneous and visceral fat with Esaote Megas GPX machine and 3.5-7.5 MHz variable frequency transducer. Epicardial adipose tissue measured by echocardiography is correlated with waist circumference (p < 0.05), visceral adipose tissue thickness measured by ultrasonography (US) and is not correlated with body mass index (p = 0.315), hip and thigh circumference or subcutaneous fat thickness measured by US. Our study confirms that US assessment of epicardial fat correlates with anthropometric and US measurements of the central fat, representing an indirect but reliable marker of the visceral fat.

Surgical reduction of adipose tissue in the male Sprague-Dawley rat.

PubMed

Kral, J G

1976-10-01

The lipostatic theory of regulation of adipose tissue mass was tested by a method for surgical reduction (adipectomy) of 24% of the total body fat of nonobese adult Sprague-Dawley rats, as judged from carcass analyses. The reduction persisted during an observation period of 12 wk without any evidence of altered food intake, weight gain, or compensatory hypertrophy or hyperplasia of adipose tissue compared with sham-operated controls. No changes were found in serum free fatty acids, glycerol, triglycerides, cholesterol, or insulin between adipectomized and control animals, implying an intact quantitative function of the remaining adipose tissue. It is concluded that the size of the adipocytes rather than the number is important for a presumed lipostatic regulation of adipose tissue mass in the adult male Sprague-Dawley rat.

FABP4 Dynamics in Obesity: Discrepancies in Adipose Tissue and Liver Expression Regarding Circulating Plasma Levels

PubMed Central

Ceperuelo-Mallafré, Victoria; Garrido-Sanchez, Lourdes; Miranda, Merce; Clemente-Postigo, Mercedes; Pérez-Pérez, Rafael; Peral, Belen; Cardona, Fernando; Fernández-Real, Jose Manuel; Tinahones, Francisco J.; Vendrell, Joan

2012-01-01

Background FABP4 is predominantly expressed in adipose tissue, and its circulating levels are linked with obesity and a poor atherogenic profile. Objective In patients with a wide BMI range, we analyze FABP4 expression in adipose and hepatic tissues in the settings of obesity and insulin resistance. Associations between FABP4 expression in adipose tissue and the FABP4 plasma level as well as the main adipogenic and lipolytic genes expressed in adipose tissue were also analyzed. Methods The expression of several lipogenic, lipolytic, PPAR family and FABP family genes was analyzed by real time PCR. FABP4 protein expression in total adipose tissues and its fractions were determined by western blot. Results In obesity FABP4 expression was down-regulated (at both mRNA and protein levels), with its levels mainly predicted by ATGL and inversely by the HOMA-IR index. The BMI appeared as the only determinant of the FABP4 variation in both adipose tissue depots. FABP4 plasma levels showed a significant progressive increase according to BMI but no association was detected between FABP4 circulating levels and SAT or VAT FABP4 gene expression. The gene expression of FABP1, FABP4 and FABP5 in hepatic tissue was significantly higher in tissue from the obese IR patients compared to the non-IR group. Conclusion The inverse pattern in FABP4 expression between adipose and hepatic tissue observed in morbid obese patients, regarding the IR context, suggests that both tissues may act in a balanced manner. These differences may help us to understand the discrepancies between circulating plasma levels and adipose tissue expression in obesity. PMID:23139800

Automated adipose study for assessing cancerous human breast tissue using optical coherence tomography (Conference Presentation)

NASA Astrophysics Data System (ADS)

Gan, Yu; Yao, Xinwen; Chang, Ernest W.; Bin Amir, Syed A.; Hibshoosh, Hanina; Feldman, Sheldon; Hendon, Christine P.

2017-02-01

Breast cancer is the third leading cause of death in women in the United States. In human breast tissue, adipose cells are infiltrated or replaced by cancer cells during the development of breast tumor. Therefore, an adipose map can be an indicator of identifying cancerous region. We developed an automated classification method to generate adipose map within human breast. To facilitate the automated classification, we first mask the B-scans from OCT volumes by comparing the signal noise ratio with a threshold. Then, the image was divided into multiple blocks with a size of 30 pixels by 30 pixels. In each block, we extracted texture features such as local standard deviation, entropy, homogeneity, and coarseness. The features of each block were input to a probabilistic model, relevance vector machine (RVM), which was trained prior to the experiment, to classify tissue types. For each block within the B-scan, RVM identified the region with adipose tissue. We calculated the adipose ratio as the number of blocks identified as adipose over the total number of blocks within the B-scan. We obtained OCT images from patients (n = 19) in Columbia medical center. We automatically generated the adipose maps from 24 B-scans including normal samples (n = 16) and cancerous samples (n = 8). We found the adipose regions show an isolated pattern that in cancerous tissue while a clustered pattern in normal tissue. Moreover, the adipose ratio (52.30 ± 29.42%) in normal tissue was higher than the that in cancerous tissue (12.41 ± 10.07%).

Adipose Tissue-Derived Pericytes for Cartilage Tissue Engineering.

PubMed

Zhang, Jinxin; Du, Chunyan; Guo, Weimin; Li, Pan; Liu, Shuyun; Yuan, Zhiguo; Yang, Jianhua; Sun, Xun; Yin, Heyong; Guo, Quanyi; Zhou, Chenfu

2017-01-01

Mesenchymal stem cells (MSCs) represent a promising alternative source for cartilage tissue engineering. However, MSC culture is labor-intensive, so these cells cannot be applied immediately to regenerate cartilage for clinical purposes. Risks during the ex vivo expansion of MSCs, such as infection and immunogenicity, can be a bottleneck in their use in clinical tissue engineering. As a novel stem cell source, pericytes are generally considered to be the origin of MSCs. Pericytes do not have to undergo time-consuming ex vivo expansion because they are uncultured cells. Adipose tissue is another optimal stem cell reservoir. Because adipose tissue is well vascularized, a considerable number of pericytes are located around blood vessels in this accessible and dispensable tissue, and autologous pericytes can be applied immediately for cartilage regeneration. Thus, we suggest that adipose tissue-derived pericytes are promising seed cells for cartilage regeneration. Many studies have been performed to develop isolation methods for the adipose tissuederived stromal vascular fraction (AT-SVF) using lipoaspiration and sorting pericytes from AT-SVF. These methods are useful for sorting a large number of viable pericytes for clinical therapy after being combined with automatic isolation using an SVF device and automatic magnetic-activated cell sorting. These tools should help to develop one-step surgery for repairing cartilage damage. However, the use of adipose tissue-derived pericytes as a cell source for cartilage tissue engineering has not drawn sufficient attention and preclinical studies are needed to improve cell purity, to increase sorting efficiency, and to assess safety issues of clinical applications. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

Mechanically robust cryogels with injectability and bioprinting supportability for adipose tissue engineering.

PubMed

Qi, Dianjun; Wu, Shaohua; Kuss, Mitchell A; Shi, Wen; Chung, Soonkyu; Deegan, Paul T; Kamenskiy, Alexey; He, Yini; Duan, Bin

2018-05-26

Bioengineered adipose tissues have gained increased interest as a promising alternative to autologous tissue flaps and synthetic adipose fillers for soft tissue augmentation and defect reconstruction in clinic. Although many scaffolding materials and biofabrication methods have been investigated for adipose tissue engineering in the last decades, there are still challenges to recapitulate the appropriate adipose tissue microenvironment, maintain volume stability, and induce vascularization to achieve long-term function and integration. In the present research, we fabricated cryogels consisting of methacrylated gelatin, methacrylated hyaluronic acid, and 4arm poly(ethylene glycol) acrylate (PEG-4A) by using cryopolymerization. The cryogels were repeatedly injectable and stretchable, and the addition of PEG-4A improved the robustness and mechanical properties. The cryogels supported human adipose progenitor cell (HWA) and adipose derived mesenchymal stromal cell adhesion, proliferation, and adipogenic differentiation and maturation, regardless of the addition of PEG-4A. The HWA laden cryogels facilitated the co-culture of human umbilical vein endothelial cells (HUVEC) and capillary-like network formation, which in return also promoted adipogenesis. We further combined cryogels with 3D bioprinting to generate handleable adipose constructs with clinically relevant size. 3D bioprinting enabled the deposition of multiple bioinks onto the cryogels. The bioprinted flap-like constructs had an integrated structure without delamination and supported vascularization. Adipose tissue engineering is promising for reconstruction of soft tissue defects, and also challenging for restoring and maintaining soft tissue volume and shape, and achieving vascularization and integration. In this study, we fabricated cryogels with mechanical robustness, injectability, and stretchability by using cryopolymerization. The cryogels promoted cell adhesion, proliferation, and adipogenic differentiation and maturation of human adipose progenitor cells and adipose derived mesenchymal stromal cells. Moreover, the cryogels also supported 3D bioprinting on top, forming vascularized adipose constructs. This study demonstrates the potential of the implementation of cryogels for generating volume-stable adipose tissue constructs and provides a strategy to fabricate vascularized flap-like constructs for complex soft tissue regeneration. Copyright © 2018. Published by Elsevier Ltd.

Lysophosphatidic acid receptor mRNA levels in heart and white adipose tissue are associated with obesity in mice and humans

PubMed Central

Perez, Lester J.; Nzirorera, Carine; Tozer, Kathleen; D’Souza, Kenneth; Trivedi, Purvi C.; Aguiar, Christie; Yip, Alexandra M.; Shea, Jennifer; Brunt, Keith R.; Legare, Jean-Francois; Hassan, Ansar; Pulinilkunnil, Thomas

2017-01-01

Background Lysophosphatidic acid (LPA) receptor signaling has been implicated in cardiovascular and obesity-related metabolic disease. However, the distribution and regulation of LPA receptors in the myocardium and adipose tissue remain unclear. Objectives This study aimed to characterize the mRNA expression of LPA receptors (LPA1-6) in the murine and human myocardium and adipose tissue, and its regulation in response to obesity. Methods LPA receptor mRNA levels were determined by qPCR in i) heart ventricles, isolated cardiomyocytes, and perigonadal adipose tissue from chow or high fat-high sucrose (HFHS)-fed male C57BL/6 mice, ii) 3T3-L1 adipocytes and HL-1 cardiomyocytes under conditions mimicking gluco/lipotoxicity, and iii) human atrial and subcutaneous adipose tissue from non-obese, pre-obese, and obese cardiac surgery patients. Results LPA1-6 were expressed in myocardium and white adipose tissue from mice and humans, except for LPA3, which was undetectable in murine adipocytes and human adipose tissue. Obesity was associated with increased LPA4, LPA5 and/or LPA6 levels in mice ventricles and cardiomyocytes, HL-1 cells exposed to high palmitate, and human atrial tissue. LPA4 and LPA5 mRNA levels in human atrial tissue correlated with measures of obesity. LPA5 mRNA levels were increased in HFHS-fed mice and insulin resistant adipocytes, yet were reduced in adipose tissue from obese patients. LPA4, LPA5, and LPA6 mRNA levels in human adipose tissue were negatively associated with measures of obesity and cardiac surgery outcomes. This study suggests that obesity leads to marked changes in LPA receptor expression in the murine and human heart and white adipose tissue that may alter LPA receptor signaling during obesity. PMID:29236751

Successful isolation of viable adipose-derived stem cells from human adipose tissue subject to long-term cryopreservation: positive implications for adult stem cell-based therapeutics in patients of advanced age.

PubMed

Devitt, Sean M; Carter, Cynthia M; Dierov, Raia; Weiss, Scott; Gersch, Robert P; Percec, Ivona

2015-01-01

We examined cell isolation, viability, and growth in adipose-derived stem cells harvested from whole adipose tissue subject to different cryopreservation lengths (2-1159 days) from patients of varying ages (26-62 years). Subcutaneous abdominal adipose tissue was excised during abdominoplasties and was cryopreserved. The viability and number of adipose-derived stem cells isolated were measured after initial isolation and after 9, 18, and 28 days of growth. Data were analyzed with respect to cryopreservation duration and patient age. Significantly more viable cells were initially isolated from tissue cryopreserved <1 year than from tissue cryopreserved >2 years, irrespective of patient age. However, this difference did not persist with continued growth and there were no significant differences in cell viability or growth at subsequent time points with respect to cryopreservation duration or patient age. Mesenchymal stem cell markers were maintained in all cohorts tested throughout the duration of the study. Consequently, longer cryopreservation negatively impacts initial live adipose-derived stem cell isolation; however, this effect is neutralized with continued cell growth. Patient age does not significantly impact stem cell isolation, viability, or growth. Cryopreservation of adipose tissue is an effective long-term banking method for isolation of adipose-derived stem cells in patients of varying ages.

The structure and possible functions of the milkfish Chanos chanos adipose eyelid.

PubMed

Chang, C-H; Chiao, C-C; Yan, H Y

2009-07-01

Basic histological sections (with different staining methods) and scanning electron microscopy (SEM) examinations showed that there were three distinctive layers in the adipose eyelid of milkfish Chanos chanos, which is found in the cephalie region and covers the entire eye. The outer and inner layers were epithelial tissues and the middle layer was composed of connective tissue formed by type I collagen fibrils. No adipose tissue was found in any of the three layers of the so-called adipose eyelid. Examination by transmission spectrophotometer showed that the adipose tissue could filter out ambient light with a wavelength shorter than 305 nm. A photoretinoscope was used to investigate whether the adipose eyelid influenced the mechanism of eye focusing. Eye diopter values did not differ before or after eyelid removal, which indicated that the adipose eyelid did not play a role in eye focusing. In light of these findings, it is suggested that the adipose eyelid serves to block exposure of harmful ultraviolet light into eyes and may also to offer some protection against impact to the eye in the aquatic environment.

Quantification of cefazolin in serum and adipose tissue by ultra high performance liquid chromatography-Tandem mass spectrometry (UHPLC-MS/MS): application to a pilot study of obese women undergoing cesarean delivery.

PubMed

Lillico, Ryan; Sayre, Casey L; Sitar, Daniel S; Davies, Neal M; Baron, Cynthia M; Lakowski, Ted M

2016-09-15

Higher doses of cefazolin are required in obese patients for preoperative antibiotic prophylaxis, owing to its low lipophilicity. An ultra high performance liquid chromatography-tandem mass spectrometry method was developed to quantify cefazolin in serum and adipose tissue from 6 obese patients undergoing cesarean delivery, and using stable-isotope labeled cefazolin as an internal standard. The method has a 2μg/g lower limit of quantitation. The concentration in adipose tissue was 3.4±1.6μg/mL, which is less than half of the reported minimum inhibitory concentration of 8μg/mL for cefazolin. Serum cefazolin concentrations were more than 30-fold higher than in adipose tissue. Copyright © 2016 Elsevier B.V. All rights reserved.

Correlation of X-ray computed tomography with quantitative nuclear magnetic resonance methods for pre-clinical measurement of adipose and lean tissues in living mice.

PubMed

Metzinger, Matthew N; Miramontes, Bernadette; Zhou, Peng; Liu, Yueying; Chapman, Sarah; Sun, Lucy; Sasser, Todd A; Duffield, Giles E; Stack, M Sharon; Leevy, W Matthew

2014-10-08

Numerous obesity studies have coupled murine models with non-invasive methods to quantify body composition in longitudinal experiments, including X-ray computed tomography (CT) or quantitative nuclear magnetic resonance (QMR). Both microCT and QMR have been separately validated with invasive techniques of adipose tissue quantification, like post-mortem fat extraction and measurement. Here we report a head-to-head study of both protocols using oil phantoms and mouse populations to determine the parameters that best align CT data with that from QMR. First, an in vitro analysis of oil/water mixtures was used to calibrate and assess the overall accuracy of microCT vs. QMR data. Next, experiments were conducted with two cohorts of living mice (either homogenous or heterogeneous by sex, age and genetic backgrounds) to assess the microCT imaging technique for adipose tissue segmentation and quantification relative to QMR. Adipose mass values were obtained from microCT data with three different resolutions, after which the data were analyzed with different filter and segmentation settings. Strong linearity was noted between the adipose mass values obtained with microCT and QMR, with optimal parameters and scan conditions reported herein. Lean tissue (muscle, internal organs) was also segmented and quantified using the microCT method relative to the analogous QMR values. Overall, the rigorous calibration and validation of the microCT method for murine body composition, relative to QMR, ensures its validity for segmentation, quantification and visualization of both adipose and lean tissues.

Regulation of the Fibrosis and Angiogenesis Promoter SPARC/Osteonectin in Human Adipose Tissue by Weight Change, Leptin, Insulin, and Glucose

PubMed Central

Kos, Katrina; Wong, Steve; Tan, Bee; Gummesson, Anders; Jernas, Margareta; Franck, Niclas; Kerrigan, David; Nystrom, Fredrik H.; Carlsson, Lena M.S.; Randeva, Harpal S.; Pinkney, Jonathan H.; Wilding, John P.H.

2009-01-01

OBJECTIVE Matricellular Secreted Protein, Acidic and Rich in Cysteine (SPARC), originally discovered in bone as osteonectin, is a mediator of collagen deposition and promotes fibrosis. Adipose tissue collagen has recently been found to be linked with metabolic dysregulation. Therefore, we tested the hypothesis that SPARC in human adipose tissue is influenced by glucose metabolism and adipokines. RESEARCH DESIGN AND METHODS Serum and adipose tissue biopsies were obtained from morbidly obese nondiabetic subjects undergoing bariatric surgery and lean control subjects for analysis of metabolic markers, SPARC, and various cytokines (RT-PCR). Additionally, 24 obese subjects underwent a very-low-calorie diet of 1,883 kJ (450 kcal)/day for 16 weeks and serial subcutaneous-abdominal-adipose tissue (SCAT) biopsies (weight loss: 28 ± 3.7 kg). Another six lean subjects underwent fast-food–based hyperalimentation for 4 weeks (weight gain: 7.2 ± 1.6 kg). Finally, visceral adipose tissue explants were cultured with recombinant leptin, insulin, and glucose, and SPARC mRNA and protein expression determined by Western blot analyses. RESULTS SPARC expression in human adipose tissue correlated with fat mass and was higher in SCAT. Weight loss induced by very-low-calorie diet lowered SPARC expression by 33% and increased by 30% in adipose tissue of subjects gaining weight after a fast-food diet. SPARC expression was correlated with leptin independent of fat mass and correlated with homeostasis model assessment–insulin resistance. In vitro experiments showed that leptin and insulin potently increased SPARC production dose dependently in visceral adipose tissue explants, while glucose decreased SPARC protein. CONCLUSIONS Our data suggest that SPARC expression is predominant in subcutaneous fat and its expression and secretion in adipose tissue are influenced by fat mass, leptin, insulin, and glucose. The profibrotic effects of SPARC may contribute to metabolic dysregulation in obesity. PMID:19509023

Reference genes for quantitative PCR in the adipose tissue of mice with metabolic disease.

PubMed

Almeida-Oliveira, Fernanda; Leandro, João G B; Ausina, Priscila; Sola-Penna, Mauro; Majerowicz, David

2017-04-01

Obesity and diabetes are metabolic diseases and they are increasing in prevalence. The dynamics of gene expression associated with these diseases is fundamental to identifying genes involved in related biological processes. qPCR is a sensitive technique for mRNA quantification and the most commonly used method in gene-expression studies. However, the reliability of these results is directly influenced by data normalization. As reference genes are the major normalization method used, this work aims to identify reference genes for qPCR in adipose tissues of mice with type-I diabetes or obesity. We selected 12 genes that are commonly used as reference genes. The expression of these genes in the adipose tissues of mice was analyzed in the context of three different experimental protocols: 1) untreated animals; 2) high-fat-diet animals; and 3) streptozotocin-treated animals. Gene-expression stability was analyzed using four different algorithms. Our data indicate that TATA-binding protein is stably expressed across adipose tissues in control animals. This gene was also a useful reference when the brown adipose tissues of control and obese mice were analyzed. The mitochondrial ATP synthase F1 complex gene exhibits stable expression in subcutaneous and perigonadal adipose tissue from control and obese mice. Moreover, this gene is the best reference for qPCR normalization in adipose tissue from streptozotocin-treated animals. These results show that there is no perfect stable gene suited for use under all experimental conditions. In conclusion, the selection of appropriate genes is a prerequisite to ensure qPCR reliability and must be performed separately for different experimental protocols. Copyright © 2017 Elsevier Masson SAS. All rights reserved.

High intensity interval training improves liver and adipose tissue insulin sensitivity

PubMed Central

Marcinko, Katarina; Sikkema, Sarah R.; Samaan, M. Constantine; Kemp, Bruce E.; Fullerton, Morgan D.; Steinberg, Gregory R.

2015-01-01

Objective Endurance exercise training reduces insulin resistance, adipose tissue inflammation and non-alcoholic fatty liver disease (NAFLD), an effect often associated with modest weight loss. Recent studies have indicated that high-intensity interval training (HIIT) lowers blood glucose in individuals with type 2 diabetes independently of weight loss; however, the organs affected and mechanisms mediating the glucose lowering effects are not known. Intense exercise increases phosphorylation and inhibition of acetyl-CoA carboxylase (ACC) by AMP-activated protein kinase (AMPK) in muscle, adipose tissue and liver. AMPK and ACC are key enzymes regulating fatty acid metabolism, liver fat content, adipose tissue inflammation and insulin sensitivity but the importance of this pathway in regulating insulin sensitivity with HIIT is unknown. Methods In the current study, the effects of 6 weeks of HIIT were examined using obese mice with serine–alanine knock-in mutations on the AMPK phosphorylation sites of ACC1 and ACC2 (AccDKI) or wild-type (WT) controls. Results HIIT lowered blood glucose and increased exercise capacity, food intake, basal activity levels, carbohydrate oxidation and liver and adipose tissue insulin sensitivity in HFD-fed WT and AccDKI mice. These changes occurred independently of weight loss or reductions in adiposity, inflammation and liver lipid content. Conclusions These data indicate that HIIT lowers blood glucose levels by improving adipose and liver insulin sensitivity independently of changes in adiposity, adipose tissue inflammation, liver lipid content or AMPK phosphorylation of ACC. PMID:26909307

Fully automated adipose tissue measurement on abdominal CT

NASA Astrophysics Data System (ADS)

Yao, Jianhua; Sussman, Daniel L.; Summers, Ronald M.

2011-03-01

Obesity has become widespread in America and has been associated as a risk factor for many illnesses. Adipose tissue (AT) content, especially visceral AT (VAT), is an important indicator for risks of many disorders, including heart disease and diabetes. Measuring adipose tissue (AT) with traditional means is often unreliable and inaccurate. CT provides a means to measure AT accurately and consistently. We present a fully automated method to segment and measure abdominal AT in CT. Our method integrates image preprocessing which attempts to correct for image artifacts and inhomogeneities. We use fuzzy cmeans to cluster AT regions and active contour models to separate subcutaneous and visceral AT. We tested our method on 50 abdominal CT scans and evaluated the correlations between several measurements.

Disconnect Between Adipose Tissue Inflammation and Cardiometabolic Dysfunction in Ossabaw Pigs

PubMed Central

Vieira-Potter, Victoria J.; Lee, Sewon; Bayless, David S.; Scroggins, Rebecca J.; Welly, Rebecca J.; Fleming, Nicholas J.; Smith, Thomas N.; Meers, Grace M.; Hill, Michael A.; Rector, R. Scott; Padilla, Jaume

2015-01-01

Objective The Ossabaw pig is emerging as an attractive model of human cardiometabolic disease due to its size and susceptibility to atherosclerosis, among other characteristics. Here we investigated the relationship between adipose tissue inflammation and metabolic dysfunction in this model. Methods Young female Ossabaw pigs were fed a western-style high-fat diet (HFD) (n=4) or control low-fat diet (LFD) (n=4) for a period of 9 months and compared for cardiometabolic outcomes and adipose tissue inflammation. Results The HFD-fed “OBESE” pigs were 2.5 times heavier (p<0.001) than LFD-fed “LEAN” pigs and developed severe obesity. HFD-feeding caused pronounced dyslipidemia, hypertension, insulin resistance (systemic and adipose) as well as induction of inflammatory genes, impairments in vasomotor reactivity to insulin and atherosclerosis in the coronary arteries. Remarkably, visceral, subcutaneous and perivascular adipose tissue inflammation (via FACS analysis and RT-PCR) was not increased in OBESE pigs, nor were circulating inflammatory cytokines. Conclusions These findings reveal a disconnect between adipose tissue inflammation and cardiometabolic dysfunction induced by western diet feeding in the Ossabaw pig model. PMID:26524201

Multiaxial mechanical properties and constitutive modeling of human adipose tissue: a basis for preoperative simulations in plastic and reconstructive surgery.

PubMed

Sommer, Gerhard; Eder, Maximilian; Kovacs, Laszlo; Pathak, Heramb; Bonitz, Lars; Mueller, Christoph; Regitnig, Peter; Holzapfel, Gerhard A

2013-11-01

A preoperative simulation of soft tissue deformations during plastic and reconstructive surgery is desirable to support the surgeon's planning and to improve surgical outcomes. The current development of constitutive adipose tissue models, for the implementation in multilayer computational frameworks for the simulation of human soft tissue deformations, has proved difficult because knowledge of the required mechanical parameters of fat tissue is limited. Therefore, for the first time, human abdominal adipose tissues were mechanically investigated by biaxial tensile and triaxial shear tests. The results of this study suggest that human abdominal adipose tissues under quasi-static and dynamic multiaxial loadings can be characterized as a nonlinear, anisotropic and viscoelastic soft biological material. The nonlinear and anisotropic features are consequences of the material's collagenous microstructure. The aligned collagenous septa observed in histological investigations causes the anisotropy of the tissue. A hyperelastic model used in this study was appropriate to represent the quasi-static multiaxial mechanical behavior of fat tissue. The constitutive parameters are intended to serve as a basis for soft tissue simulations using the finite element method, which is an apparent method for obtaining promising results in the field of plastic and reconstructive surgery. Copyright © 2013 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

Magnetic Resonance Imaging of Adipose Tissue in Metabolic Dysfunction.

PubMed

Franz, Daniela; Syväri, Jan; Weidlich, Dominik; Baum, Thomas; Rummeny, Ernst J; Karampinos, Dimitrios C

2018-06-06

 Adipose tissue has become an increasingly important tissue target in medicine. It plays a central role in the storage and release of energy throughout the human body and has recently gained interest for its endocrinologic function. Magnetic resonance imaging (MRI) is an established method for quantitative direct evaluation of adipose tissue distribution, and is used increasingly as the modality of choice for metabolic phenotyping. The purpose of this review was the identification and presentation of the currently available literature on MRI of adipose tissue in metabolic dysfunction.  A PubMed (http://www.ncbi.nlm.nih.gov/pubmed) keyword search up to August 2017 without starting date limitation was performed and reference lists of relevant articles were searched.  MRI provides excellent tools for the evaluation of adipose tissue distribution and further characterization of the tissue. Standard as well as newly developed MRI techniques allow a risk stratification for the development of metabolic dysfunction and enable monitoring without the use of ionizing radiation or contrast material.   · Different types of adipose tissue play a crucial role in various types of metabolic dysfunction.. · Magnetic resonance imaging (MRI) is an excellent tool for noninvasive adipose tissue evaluation with respect to distribution, composition and metabolic activity.. · Both standard and newly developed MRI techniques can be used for risk stratification for the development of metabolic dysfunction and allow monitoring without the use of ionizing radiation or contrast material.. · Franz D, Syväri J, Weidlich D et al. Magnetic Resonance Imaging of Adipose Tissue in Metabolic Dysfunction. Fortschr Röntgenstr 2018; DOI: 10.1055/a-0612-8006. © Georg Thieme Verlag KG Stuttgart · New York.

Glucose uptake of the muscle and adipose tissues in diabetes and obesity disease models: evaluation of insulin and β3-adrenergic receptor agonist effects by 18F-FDG.

PubMed

Ishino, Seigo; Sugita, Taku; Kondo, Yusuke; Okai, Mika; Tsuchimori, Kazue; Watanabe, Masanori; Mori, Ikuo; Hosoya, Masaki; Horiguchi, Takashi; Kamiguchi, Hidenori

2017-06-01

One of the major causes of diabetes and obesity is abnormality in glucose metabolism and glucose uptake in the muscle and adipose tissue based on an insufficient action of insulin. Therefore, many of the drug discovery programs are based on the concept of stimulating glucose uptake in these tissues. Improvement of glucose metabolism has been assessed based on blood parameters, but these merely reflect the systemic reaction to the drug administered. We have conducted basic studies to investigate the usefulness of glucose uptake measurement in various muscle and adipose tissues in pharmacological tests using disease-model animals. A radiotracer for glucose, 18 F-2-deoxy-2-fluoro-D-glucose ( 18 F-FDG), was administered to Wistar fatty rats (type 2 diabetes model), DIO mouse (obese model), and the corresponding control animals, and the basal glucose uptake in the muscle and adipose (white and brown) tissues were compared using biodistribution method. Moreover, insulin and a β3 agonist (CL316,243), which are known to stimulate glucose uptake in the muscle and adipose tissues, were administered to assess their effect. 18 F-FDG uptake in each tissue was measured as the radioactivity and the distribution was confirmed by autoradiography. In Wistar fatty rats, all the tissues measured showed a decrease in the basal level of glucose uptake when compared to Wistar lean rats. On the other hand, the same trend was observed only in the white adipose tissue in DIO mice, while brown adipose tissue showed increments in the basal glucose uptake in this model. Insulin administration stimulated glucose uptake in both Wistar lean and fatty rats, although the responses were inhibited in Wistar fatty rats. The same tendency was shown also in control mice, but clear increments in glucose uptake were not observed in the muscle and brown adipose tissue of DIO mice after insulin administration. β3 agonist administration showed the similar trend in Wistar lean and fatty rats as insulin, while the responses were inhibited in the adipose tissues of Wistar fatty rats. A system to monitor tissue glucose uptake with 18 F-FDG enabled us to detect clear differences in basal glucose uptake between disease-model animals and their corresponding controls. The responses in the tissues to insulin or β3 agonist could be identified. Taken as a whole, the biodistribution method with 18 F-FDG was confirmed to be useful for pharmacological evaluation of anti-diabetic or anti-obesity drugs using disease-model animals.

Optimized adipose tissue engineering strategy based on a neo-mechanical processing method.

PubMed

He, Yunfan; Lin, Maohui; Wang, Xuecen; Guan, Jingyan; Dong, Ziqing; Feng, Lu; Xing, Malcolm; Feng, Chuanbo; Li, Xiaojian

2018-05-26

Decellularized adipose tissue (DAT) represents a promising scaffold for adipose tissue engineering. However, the unique and prolonged lipid removal process required for adipose tissue can damage extracellular matrix (ECM) constituents. Moreover, inadequate vascularization limits the recellularization of DAT in vivo. We proposed a neo-mechanical protocol for rapidly breaking adipocytes and removing lipid content from adipose tissue. The lipid-depleted adipose tissue was then subjected to a fast and mild decellularization to fabricate high-quality DAT (M-DAT). Adipose liquid extract (ALE) derived from this mechanical process was collected and incorporated into M-DAT to further optimize in vivo recellularization. Ordinary DAT was fabricated and served as a control. This developed strategy was evaluated based on decellularization efficiency, ECM quality, and recellularization efficiency. Angiogenic factor components and angiogenic potential of ALE were evaluated in vivo and in vitro. M-DAT achieved the same decellularization efficiency, but exhibited better retention of ECM components and recellularization, compared to those with ordinary DAT. Protein quantification revealed considerable levels of angiogenic factors (basic fibroblast growth factor, epidermal growth factor, transforming growth factor-β1, and vascular endothelial growth factor) in ALE. ALE promoted tube formation in vitro and induced intense angiogenesis in M-DAT in vivo; furthermore, higher expression of the adipogenic factor PPARγ and greater numbers of adipocytes were evident following ALE treatment, compared to those in the M-DAT group. Mechanical processing of adipose tissue led to the production of high-quality M-DAT and angiogenic factor-enriched ALE. The combination of ALE and M-DAT could be a promising strategy for engineered adipose tissue construction. This article is protected by copyright. All rights reserved. © 2018 by the Wound Healing Society.

Quantitative CT imaging for adipose tissue analysis in mouse model of obesity

NASA Astrophysics Data System (ADS)

Marchadier, A.; Vidal, C.; Tafani, J.-P.; Ordureau, S.; Lédée, R.; Léger, C.

2011-03-01

In obese humans CT imaging is a validated method for follow up studies of adipose tissue distribution and quantification of visceral and subcutaneous fat. Equivalent methods in murine models of obesity are still lacking. Current small animal micro-CT involves long-term X-ray exposure precluding longitudinal studies. We have overcome this limitation by using a human medical CT which allows very fast 3D imaging (2 sec) and minimal radiation exposure. This work presents novel methods fitted to in vivo investigations of mice model of obesity, allowing (i) automated detection of adipose tissue in abdominal regions of interest, (ii) quantification of visceral and subcutaneous fat. For each mouse, 1000 slices (100μm thickness, 160 μm resolution) were acquired in 2 sec using a Toshiba medical CT (135 kV, 400mAs). A Gaussian mixture model of the Hounsfield curve of 2D slices was computed with the Expectation Maximization algorithm. Identification of each Gaussian part allowed the automatic classification of adipose tissue voxels. The abdominal region of interest (umbilical) was automatically detected as the slice showing the highest ratio of the Gaussian proportion between adipose and lean tissues. Segmentation of visceral and subcutaneous fat compartments was achieved with 2D 1/2 level set methods. Our results show that the application of human clinical CT to mice is a promising approach for the study of obesity, allowing valuable comparison between species using the same imaging materials and software analysis.

Adipose tissue branched chain amino acid (BCAA) metabolism modulates circulating BCAA levels.

PubMed

Herman, Mark A; She, Pengxiang; Peroni, Odile D; Lynch, Christopher J; Kahn, Barbara B

2010-04-09

Whereas the role of adipose tissue in glucose and lipid homeostasis is widely recognized, its role in systemic protein and amino acid metabolism is less well-appreciated. In vitro and ex vivo experiments suggest that adipose tissue can metabolize substantial amounts of branched chain amino acids (BCAAs). However, the role of adipose tissue in regulating BCAA metabolism in vivo is controversial. Interest in the contribution of adipose tissue to BCAA metabolism has been renewed with recent observations demonstrating down-regulation of BCAA oxidation enzymes in adipose tissue in obese and insulin-resistant humans. Using gene set enrichment analysis, we observe alterations in adipose-tissue BCAA enzyme expression caused by adipose-selective genetic alterations in the GLUT4 glucose-transporter expression. We show that the rate of adipose tissue BCAA oxidation per mg of tissue from normal mice is higher than in skeletal muscle. In mice overexpressing GLUT4 specifically in adipose tissue, we observe coordinate down-regulation of BCAA metabolizing enzymes selectively in adipose tissue. This decreases BCAA oxidation rates in adipose tissue, but not in muscle, in association with increased circulating BCAA levels. To confirm the capacity of adipose tissue to modulate circulating BCAA levels in vivo, we demonstrate that transplantation of normal adipose tissue into mice that are globally defective in peripheral BCAA metabolism reduces circulating BCAA levels by 30% (fasting)-50% (fed state). These results demonstrate for the first time the capacity of adipose tissue to catabolize circulating BCAAs in vivo and that coordinate regulation of adipose-tissue BCAA enzymes may modulate circulating BCAA levels.

Acerola (Malpighia emarginata DC.) juice intake protects against alterations to proteins involved in inflammatory and lipolysis pathways in the adipose tissue of obese mice fed a cafeteria diet

PubMed Central

2014-01-01

Background Obesity has been studied as a metabolic and an inflammatory disease and is characterized by increases in the production of pro-inflammatory adipokines in the adipose tissue. To elucidate the effects of natural dietary components on the inflammatory and metabolic consequences of obesity, we examined the effects of unripe, ripe and industrial acerola juice (Malpighia emarginata DC.) on the relevant inflammatory and lipolysis proteins in the adipose tissue of mice with cafeteria diet-induced obesity. Materials/methods Two groups of male Swiss mice were fed on a standard diet (STA) or a cafeteria diet (CAF) for 13 weeks. Afterwards, the CAF-fed animals were divided into five subgroups, each of which received a different supplement for one further month (water, unripe acerola juice, ripe acerola juice, industrial acerola juice, or vitamin C) by gavage. Enzyme-linked immunosorbent assays, Western blotting, a colorimetric method and histology were utilized to assess the observed data. Results The CAF water (control obese) group showed a significant increase in their adiposity indices and triacylglycerol levels, in addition to a reduced IL-10/TNF-α ratio in the adipose tissue, compared with the control lean group. In contrast, acerola juice and Vitamin C intake ameliorated the weight gain, reducing the TAG levels and increasing the IL-10/TNF-α ratio in adipose tissue. In addition, acerola juice intake led to reductions both in the level of phosphorylated JNK and to increases in the phosphorylation of IκBα and HSLser660 in adipose tissue. Conclusions Taken together, these results suggest that acerola juice reduces low-grade inflammation and ameliorates obesity-associated defects in the lipolytic processes. PMID:24495336

The effect of dietary carbohydrate on genes for fatty acid synthase and inflammatory cytokines in adipose tissues from lean and obese subjects.

PubMed

Hudgins, Lisa C; Baday, Aline; Hellerstein, Marc K; Parker, Thomas S; Levine, Daniel M; Seidman, Cynthia E; Neese, Richard A; Tremaroli, Jolanta D; Hirsch, Jules

2008-04-01

Hepatic de novo lipogenesis (DNL) is markedly stimulated in humans by low-fat diets enriched in simple sugars. However, the dietary responsiveness of the key enzyme controlling DNL in human adipose tissue, fatty acid synthase (FAS), is uncertain. Adipose tissue mRNA for FAS is increased in lean and obese subjects when hepatic DNL is elevated by a eucaloric, low-fat, high-sugar diet. Twelve lean and seven obese volunteers were given two eucaloric diets (10% vs. 30% fat; 75% vs. 55% carbohydrate; sugar/starch 60/40) each for 2 weeks by a random-order cross-over design. FAS mRNA in abdominal and gluteal adipose tissues was compared to hepatic DNL measured in serum by isotopic and nonisotopic methods. Adipose tissue mRNA for tumor necrosis factor-alpha and IL-6, which are inflammatory cytokines that modulate DNL, was also assayed. The low-fat high-sugar diet induced a 4-fold increase in maximum hepatic DNL (P<.001) but only a 1.3-fold increase in adipose tissue FAS mRNA (P=.029) and no change in cytokine mRNA. There was a borderline significant positive correlation between changes in FAS mRNA and hepatic DNL (P=.039). Compared to lean subjects, obese subjects had lower levels of FAS mRNA and higher levels of cytokine mRNA (P<.001). The results suggest that key elements of human adipose tissue DNL are less responsive to dietary carbohydrate than is hepatic DNL and may be regulated by diet-independent factors. Irrespective of diet, there is reduced expression of the FAS gene and increased expression of cytokine genes in adipose tissues of obese subjects.

Fatty acids do not pay the toll: effect of SFA and PUFA on human adipose tissue and mature adipocytes inflammation

PubMed Central

2012-01-01

Background On the basis that high fat diet induces inflammation in adipose tissue, we wanted to test the effect of dietary saturated and polysunsaturated fatty acids on human adipose tissue and adipocytes inflammation. Moreover we wanted to determine if TLR2 and TLR4 are involved in this pathway. Methods Human adipose tissue and adipocytes primary cultures were treated with endotoxin-free BSA conjugated with SFA (lauric acid and palmitic acid - LA and PA) and PUFA (eicosapentaeneic acid, docosahexaenoic acid and oleic acid - EPA, DHA and OA) with or without LPS. Cytokines were then assayed by ELISA (TNF-alpha, IL-6 and MCP-1). In order to determine if TLR2 and TLR4 are activated by fatty acid (FA), we used HEK-Blue cells transfected by genes from TLR2 or TLR4 pathways associated with secreted alkaline phosphatase reporter gene. Results None of the FA tested in HEK-Blue cells were able to activate TLR2 or TLR4, which is concordant with the fact that after FA treatment, adipose tissue and adipocytes cytokines levels remain the same as controls. However, all the PUFA tested: DHA, EPA and to a lesser extent OA down-regulated TNF-alpha, IL-6 and MCP-1 secretion in human adipose tissue and adipocytes cultures. Conclusions This study first confirms that FA do not activate TLR2 and TLR4. Moreover by using endotoxin-free BSA, both SFA and PUFA tested were not proinflammatory in human adipose tissue and adipocytes model. More interestingly we showed that some PUFA exert an anti-inflammatory action in human adipose tissue and adipocytes model. These results are important since they clarify the relationship between dietary fatty acids and inflammation linked to obesity. PMID:23259689

Activation of natriuretic peptides and the sympathetic nervous system following Roux-en-Y gastric bypass is associated with gonadal adipose tissues browning

PubMed Central

Neinast, Michael D.; Frank, Aaron P.; Zechner, Juliet F.; Li, Quanlin; Vishvanath, Lavanya; Palmer, Biff F.; Aguirre, Vincent; Gupta, Rana K.; Clegg, Deborah J.

2015-01-01

Objective Roux-en-Y gastric bypass (RYGB) is an effective method of weight loss and remediation of type-2 diabetes; however, the mechanisms leading to these improvements are unclear. Additionally, adipocytes within white adipose tissue (WAT) depots can manifest characteristics of brown adipocytes. These ‘BRITE/beige’ adipocytes express uncoupling protein 1 (UCP1) and are associated with improvements in glucose homeostasis and protection from obesity. Interestingly, atrial and B-type natriuretic peptides (NPs) promote BRITE/beige adipocyte enrichment of WAT depots, an effect known as “browning.” Here, we investigate the effect of RYGB surgery on NP, NP receptors, and browning in the gonadal adipose tissues of female mice. We propose that such changes may lead to improvements in metabolic homeostasis commonly observed following RYGB. Methods Wild type, female, C57/Bl6 mice were fed a 60% fat diet ad libitum for six months. Mice were divided into three groups: Sham operated (SO), Roux-en-Y gastric bypass (RYGB), and Weight matched, sham operated (WM-SO). Mice were sacrificed six weeks following surgery and evaluated for differences in body weight, glucose homeostasis, adipocyte morphology, and adipose tissue gene expression. Results RYGB and calorie restriction induced similar weight loss and improved glucose metabolism without decreasing food intake. β3-adrenergic receptor expression increased in gonadal adipose tissue, in addition to Nppb (BNP), and NP receptors, Npr1, and Npr2. The ratio of Npr1:Npr3 and Npr2:Npr3 increased in RYGB, but not WM-SO groups. Ucp1 protein and mRNA, as well as additional markers of BRITE/beige adipose tissue and lipolytic genes increased in RYGB mice to a greater extent than calorie-restricted mice. Conclusions Upregulation of Nppb, Npr1, Npr2, and β3-adrenergic receptors in gonadal adipose tissue following RYGB was associated with increased markers of browning. This browning of gonadal adipose tissue may underpin the positive effect of RYGB on metabolic parameters and may in part be mediated through upregulation of natriuretic peptides. PMID:25973390

A microarray analysis of sexual dimorphism of adipose tissues in high-fat-diet-induced obese mice

PubMed Central

Grove, KL; Fried, SK; Greenberg, AS; Xiao, XQ; Clegg, DJ

2013-01-01

Objective A sexual dimorphism exists in body fat distribution; females deposit relatively more fat in subcutaneous/inguinal depots whereas males deposit more fat in the intra-abdominal/gonadal depot. Our objective was to systematically document depot- and sex-related differences in the accumulation of adipose tissue and gene expression, comparing differentially expressed genes in diet-induced obese mice with mice maintained on a chow diet. Research Design and Methods We used a microarray approach to determine whether there are sexual dimorphisms in gene expression in age-matched male, female or ovariectomized female (OVX) C57/BL6 mice maintained on a high-fat (HF) diet. We then compared expression of validated genes between the sexes on a chow diet. Results After exposure to a high fat diet for 12 weeks, females gained less weight than males. The microarray analyses indicate in intra-abdominal/gonadal adipose tissue in females 1642 genes differ by at least twofold between the depots, whereas 706 genes differ in subcutaneous/inguinal adipose tissue when compared with males. Only 138 genes are commonly regulated in both sexes and adipose tissue depots. Inflammatory genes (cytokine–cytokine receptor interactions and acute-phase protein synthesis) are upregulated in males when compared with females, and there is a partial reversal after OVX, where OVX adipose tissue gene expression is more ′male-like′. This pattern is not observed in mice maintained on chow. Histology of male gonadal white adipose tissue (GWAT) shows more crown-like structures than females, indicative of inflammation and adipose tissue remodeling. In addition, genes related to insulin signaling and lipid synthesis are higher in females than males, regardless of dietary exposure. Conclusions These data suggest that male and female adipose tissue differ between the sexes regardless of diet. Moreover, HF diet exposure elicits a much greater inflammatory response in males when compared with females. This data set underscores the importance of analyzing depot-, sex- and steroid-dependent regulation of adipose tissue distribution and function. PMID:20157318

Adipose tissue endocannabinoid system gene expression: depot differences and effects of diet and exercise

PubMed Central

2011-01-01

Background Alterations of endocannabinoid system in adipose tissue play an important role in lipid regulation and metabolic dysfunction associated with obesity. The purpose of this study was to determine whether gene expression levels of cannabinoid type 1 receptor (CB1) and fatty acid amide hydrolase (FAAH) are different in subcutaneous abdominal and gluteal adipose tissue, and whether hypocaloric diet and aerobic exercise influence subcutaneous adipose tissue CB1 and FAAH gene expression in obese women. Methods Thirty overweight or obese, middle-aged women (BMI = 34.3 ± 0.8 kg/m2, age = 59 ± 1 years) underwent one of three 20-week weight loss interventions: caloric restriction only (CR, N = 9), caloric restriction plus moderate-intensity aerobic exercise (CRM, 45-50% HRR, N = 13), or caloric restriction plus vigorous-intensity aerobic exercise (CRV, 70-75% HRR, N = 8). Subcutaneous abdominal and gluteal adipose tissue samples were collected before and after the interventions to measure CB1 and FAAH gene expression. Results At baseline, FAAH gene expression was higher in abdominal, compared to gluteal adipose tissue (2.08 ± 0.11 vs. 1.78 ± 0.10, expressed as target gene/β-actin mRNA ratio × 10-3, P < 0.05). Compared to pre-intervention, CR did not change abdominal, but decreased gluteal CB1 (Δ = -0.82 ± 0.25, P < 0.05) and FAAH (Δ = -0.49 ± 0.14, P < 0.05) gene expression. CRM or CRV alone did not change adipose tissue CB1 and FAAH gene expression. However, combined CRM and CRV (CRM+CRV) decreased abdominal adipose tissue FAAH gene expression (Δ = -0.37 ± 0.18, P < 0.05). The changes in gluteal CB1 and abdominal FAAH gene expression levels in the CR alone and the CRM+CRV group were different (P < 0.05) or tended to be different (P = 0.10). Conclusions There are depot differences in subcutaneous adipose tissue endocannabinoid system gene expression in obese individuals. Aerobic exercise training may preferentially modulate abdominal adipose tissue endocannabinoid-related gene expression during dietary weight loss. Trial Registration ClinicalTrials.gov: NCT00664729. PMID:22035053

Comparison of Gross Body Fat-Water Magnetic Resonance Imaging at 3 Tesla to Dual Energy X-Ray Absorptiometry in Obese Women

PubMed Central

Silver, HJ; Niswender, KD; Kullberg, J; Berglund, J; Johansson, L; Bruvold, M; Avison, MJ; Welch, EB.

2012-01-01

Improved understanding of how depot-specific adipose tissue mass predisposes to obesity-related comorbidities could yield new insights into the pathogenesis and treatment of obesity as well as metabolic benefits of weight loss. We hypothesized that three-dimensional contiguous “fat-water” MR imaging (FWMRI) covering the majority of a whole-body field of view (FOV) acquired at 3 Tesla (3T) and coupled with automated segmentation and quantification of amount, type and distribution of adipose and lean soft tissue would show great promise in body composition methodology. Precision of adipose and lean soft tissue measurements in body and trunk regions were assessed for 3T FWMRI and compared to DEXA. Anthropometric, FWMRI and DEXA measurements were obtained in twelve women with BMI 30–39.9 kg/m2. Test-retest results found coefficients of variation for FWMRI that were all under 3%: gross body adipose tissue (GBAT) 0.80%, total trunk adipose tissue (TTAT) 2.08%, visceral adipose tissue (VAT) 2.62%, subcutaneous adipose tissue (SAT) 2.11%, gross body lean soft tissue (GBLST) 0.60%, and total trunk lean soft tissue (TTLST) 2.43%. Concordance correlation coefficients between FWMRI and DEXA were 0.978, 0.802, 0.629, and 0.400 for GBAT, TTAT, GBLST and TTLST, respectively. While Bland Altman plots demonstrated agreement between FWMRI and DEXA for GBAT and TTAT, a negative bias existed for GBLST and TTLST measurements. Differences may be explained by the FWMRI FOV length and potential for DEXA to overestimate lean soft tissue. While more development is necessary, the described 3T FWMRI method combined with fully-automated segmentation is fast (<30 minutes total scan and post-processing time), noninvasive, repeatable and cost effective. PMID:23712980

Quantifying Abdominal Adipose Tissue and Thigh Muscle Volume and Hepatic Proton Density Fat Fraction: Repeatability and Accuracy of an MR Imaging-based, Semiautomated Analysis Method.

PubMed

Middleton, Michael S; Haufe, William; Hooker, Jonathan; Borga, Magnus; Dahlqvist Leinhard, Olof; Romu, Thobias; Tunón, Patrik; Hamilton, Gavin; Wolfson, Tanya; Gamst, Anthony; Loomba, Rohit; Sirlin, Claude B

2017-05-01

Purpose To determine the repeatability and accuracy of a commercially available magnetic resonance (MR) imaging-based, semiautomated method to quantify abdominal adipose tissue and thigh muscle volume and hepatic proton density fat fraction (PDFF). Materials and Methods This prospective study was institutional review board- approved and HIPAA compliant. All subjects provided written informed consent. Inclusion criteria were age of 18 years or older and willingness to participate. The exclusion criterion was contraindication to MR imaging. Three-dimensional T1-weighted dual-echo body-coil images were acquired three times. Source images were reconstructed to generate water and calibrated fat images. Abdominal adipose tissue and thigh muscle were segmented, and their volumes were estimated by using a semiautomated method and, as a reference standard, a manual method. Hepatic PDFF was estimated by using a confounder-corrected chemical shift-encoded MR imaging method with hybrid complex-magnitude reconstruction and, as a reference standard, MR spectroscopy. Tissue volume and hepatic PDFF intra- and interexamination repeatability were assessed by using intraclass correlation and coefficient of variation analysis. Tissue volume and hepatic PDFF accuracy were assessed by means of linear regression with the respective reference standards. Results Adipose and thigh muscle tissue volumes of 20 subjects (18 women; age range, 25-76 years; body mass index range, 19.3-43.9 kg/m 2 ) were estimated by using the semiautomated method. Intra- and interexamination intraclass correlation coefficients were 0.996-0.998 and coefficients of variation were 1.5%-3.6%. For hepatic MR imaging PDFF, intra- and interexamination intraclass correlation coefficients were greater than or equal to 0.994 and coefficients of variation were less than or equal to 7.3%. In the regression analyses of manual versus semiautomated volume and spectroscopy versus MR imaging, PDFF slopes and intercepts were close to the identity line, and correlations of determination at multivariate analysis (R 2 ) ranged from 0.744 to 0.994. Conclusion This MR imaging-based, semiautomated method provides high repeatability and accuracy for estimating abdominal adipose tissue and thigh muscle volumes and hepatic PDFF. © RSNA, 2017.

Adipose tissue metabolic and inflammatory responses to a mixed meal in lean, overweight and obese men.

PubMed

Travers, Rebecca L; Motta, Alexandre C; Betts, James A; Thompson, Dylan

2017-02-01

Most of what we know about adipose tissue is restricted to observations derived after an overnight fast. However, humans spend the majority of waking hours in a postprandial (fed) state, and it is unclear whether increasing adiposity impacts adipose tissue responses to feeding. The aim of this research was to investigate postprandial responses in adipose tissue across varying degrees of adiposity. Thirty males aged 35-55 years with waist circumference 81-118 cm were divided equally into groups categorized as either lean, overweight or obese. Participants consumed a meal and insulinaemic, glycaemic and lipidaemic responses were monitored over 6 h. Subcutaneous adipose tissue samples were obtained at baseline and after 6 h to examine changes in gene expression and adipose tissue secretion of various adipokines. Following consumption of the meal, insulin and glucose responses were higher with increased adiposity (total AUC effects of group; p = 0.058 and p = 0.027, respectively). At 6 h, significant time effects reflected increases in IL-6 (F = 14.7, p = 0.001) and MCP-1 (F = 10.7, p = 0.003) and reduction in IRS2 adipose tissue gene expression (F = 24.6, p < 0.001), all independent of adiposity. Ex vivo adipokine secretion from adipose tissue explants remained largely unchanged after feeding. Increased systemic measures of postprandial metabolism with greater adiposity do not translate into increased inflammatory responses within adipose tissue. Instead, postprandial adipose tissue changes may represent a normal response to feeding or a (relatively) normalized response with increased adiposity due to either similar net exposure (i.e. per g of adipose) or reduced adipose tissue responsiveness.

Investigating the mincing method for isolation of adipose-derived stem cells from pregnant women fat.

PubMed

Li, Yuan-Sheng; Chen, Pao-Jen; Wu, Li-Wei; Chou, Pei-Wen; Sun, Li-Yi; Chiou, Tzyy-Wen

2018-02-01

The success of stem cell application in regenerative medicine, usually require a stable source of stem or progenitor cells. Fat tissue represents a good source of stem cells because it is rich in stem cells and there are fewer ethical issues related to the use of such stem cells, unlike embryonic stem cells. Therefore, there has been increased interest in adipose-derived stem cells (ADSCs) for tissue engineering applications. Here, we aim to provide an easy processing method for isolating adult stem cells from human adipose tissue harvested from the subcutaneous fat of the abdominal wall during gynecologic surgery. We used a homogenizer to mince fat and compared the results with those obtained from the traditional cut method involving a sterile scalpel and forceps. Our results showed that our method provides another stable and quality source of stem cells that could be used in cases with a large quantity of fat. Furthermore, we found that pregnancy adipose-derived stem cells (P-ADSCs) could be maintained in vitro for extended periods with a stable population doubling and low senescence levels. P-ADSCs could also differentiate in vitro into adipogenic, osteogenic, chondrogenic, and insulin-producing cells in the presence of lineage-specific induction factors. In conclusion, like human lipoaspirates, adipose tissues obtained from pregnant women contain multipotent cells with better proliferation and showed great promise for use in both stem cell banking studies as well as in stem cell therapy.

Reduced Socs3 expression in adipose tissue protects female mice against obesity-induced insulin resistance

PubMed Central

Palanivel, R.; Fullerton, M. D.; Galic, S.; Honeyman, J.; Hewitt, K. A.; Jorgensen, S. B.; Steinberg, G. R.

2017-01-01

Aims/hypothesis Inflammation in obesity increases the levels of the suppressor of cytokine signalling-3 (SOCS3) protein in adipose tissue, but the physiological importance of this protein in regulating whole-body insulin sensitivity in obesity is not known. Methods We generated Socs3 floxed (wild-type, WT) and Socs3 aP2 (also known as Fabp4)-Cre null (Socs3 AKO) mice. Mice were maintained on either a regular chow or a high-fat diet (HFD) for 16 weeks during which time body mass, adiposity, glucose homeostasis and insulin sensitivity were assessed. Results The HFD increased SOCS3 levels in adipose tissue of WT but not Socs3 AKO mice. WT and Socs3 AKO mice had similar body mass and adiposity, assessed using computed tomography (CT) imaging, irrespective of diet or sex. On a control chow diet there were no differences in insulin sensitivity or glucose tolerance. When fed a HFD, female but not male Socs3 AKO mice had improved glucose tolerance as well as lower fasting glucose and insulin levels compared with WT littermates. Hyperinsulinaemic–euglycaemic clamps and positron emission tomography (PET) imaging demonstrated that improved insulin sensitivity was due to elevated adipose tissue glucose uptake. Increased insulin-stimulated glucose uptake in adipose tissue was associated with enhanced levels and activating phosphorylation of insulin receptor substrate-1 (IRS1). Conclusions/interpretation These data demonstrate that inhibiting SOCS3 production in adipose tissue of female mice is effective for improving whole-body insulin sensitivity in obesity. PMID:22872213

Reproducible MRI Measurement of Adipose Tissue Volumes in Genetic and Dietary Rodent Obesity Models

PubMed Central

Johnson, David H.; Flask, Chris A.; Ernsberger, Paul R.; Wong, Wilbur C. K.; Wilson, David L.

2010-01-01

Purpose To develop ratio MRI [lipid/(lipid+water)] methods for assessing lipid depots and compare measurement variability to biological differences in lean controls (spontaneously hypertensive rats, SHRs), dietary obese (SHR-DO), and genetic/dietary obese (SHROBs) animals. Materials and Methods Images with and without CHESS water-suppression were processed using a semi-automatic method accounting for relaxometry, chemical shift, receive coil sensitivity, and partial volume. Results Partial volume correction improved results by 10–15%. Over six operators, volume variation was reduced to 1.9 ml from 30.6 ml for single-image-analysis with intensity inhomogeneity. For three acquisitions on the same animal, volume reproducibility was <1%. SHROBs had 6X visceral and 8X subcutaneous adipose tissue than SHRs. SHR-DOs had enlarged visceral depots (3X SHRs). SHROB had significantly more subcutaneous adipose tissue, indicating a strong genetic component to this fat depot. Liver ratios in SHR-DO and SHROB were higher than SHR, indicating elevated fat content. Among SHROBs, evidence suggested a phenotype SHROB* having elevated liver ratios and visceral adipose tissue volumes. Conclusion Effects of diet and genetics on obesity were significantly larger than variations due to image acquisition and analysis, indicating that these methods can be used to assess accumulation/depletion of lipid depots in animal models of obesity. PMID:18821617

The adipose renin-angiotensin system modulates sysemic markers of insulin sensitivity activates the intrarenal renin-angiotensin system

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kim, Suyeon; Soltani-Bejnood, Morvarid; Quignard-Boulange, Annie

2006-07-01

BACKGROUND: A growing body of data provides increasing evidence that the adipose tissue renin-angiotensin system (RAS) contributes to regulation of fat mass. Beyond its paracrine actions within adipose tissue, adipocyte-derived angiotensin II (Ang II) may also impact systemic functions such as blood pressure and metabolism. METHODS AND RESULTS: We used a genetic approach to manipulate adipose RAS activity in mice and then study the consequences on metabolic parameters and on feedback regulation of the RAS. The models included deletion of the angiotensinogen (Agt) gene (Agt-KO), its expression solely in adipose tissue under the control of an adipocyte-specific promoter (aP2-Agt/ Agt-KO),more » and overexpression in adipose tissue of wild type mice (aP2-Agt). Total body weight, epididymal fat pad weight, and circulating levels of leptin, insulin and resistin were significantly decreased in Agt-KO mice, while plasma adiponectin levels were increased. Overexpression of Agt in adipose tissue resulted in increased adiposity and plasma leptin and insulin levels compared to wild type (WT) controls. Angiotensinogen and type I Ang II receptor protein levels were also markedly elevated in kidney of aP2-Agt mice, suggesting that hypertension in these animals may be in part due to stimulation of the intrarenal RAS. CONCLUSIONS: Taken together, the results from this study demonstrate that alterations in adipose RAS activity significantly alter both local and systemic physiology in a way that may contribute to the detrimental health effects of obesity.« less

Remote biopsy darting and marking of polar bears

USGS Publications Warehouse

Pagano, Anthony M.; Peacock, Elizabeth; McKinney, Melissa A.

2014-01-01

Remote biopsy darting of polar bears (Ursus maritimus) is less invasive and time intensive than physical capture and is therefore useful when capture is challenging or unsafe. We worked with two manufacturers to develop a combination biopsy and marking dart for use on polar bears. We had an 80% success rate of collecting a tissue sample with a single biopsy dart and collected tissue samples from 143 polar bears on land, in water, and on sea ice. Dye marks ensured that 96% of the bears were not resampled during the same sampling period, and we recovered 96% of the darts fired. Biopsy heads with 5 mm diameters collected an average of 0.12 g of fur, tissue, and subcutaneous adipose tissue, while biopsy heads with 7 mm diameters collected an average of 0.32 g. Tissue samples were 99.3% successful (142 of 143 samples) in providing a genetic and sex identification of individuals. We had a 64% success rate collecting adipose tissue and we successfully examined fatty acid signatures in all adipose samples. Adipose lipid content values were lower compared to values from immobilized or harvested polar bears, indicating that our method was not suitable for quantifying adipose lipid content.

Visceral and subcutaneous adipose tissue express and secrete functional alpha2hsglycoprotein (fetuin a) especially in obesity.

PubMed

Pérez-Sotelo, Diego; Roca-Rivada, Arturo; Larrosa-García, María; Castelao, Cecilia; Baamonde, Iván; Baltar, Javier; Crujeiras, Ana Belen; Seoane, Luisa María; Casanueva, Felipe F; Pardo, María

2017-02-01

The secretion of the hepatokine alpha-2-Heremans-Schmid glycoprotein/Fetuin A, implicated in pathological processes including systemic insulin resistance, by adipose tissue has been recently described. Thus, we have recently identified its presence in white adipose tissue secretomes by mass spectrometry. However, the secretion pattern and function of adipose-derived alpha-2-Heremans-Schmid glycoprotein are poorly understood. The aim of this study is to evaluate the expression and secretion of total and active phosphorylated alpha-2-Heremans-Schmid glycoprotein by adipose tissue from visceral and subcutaneous localizations in animals at different physiological and nutritional status including anorexia and obesity. Alpha-2-Heremans-Schmid glycoprotein expression and secretion in visceral adipose tissue and subcutaneous adipose tissue explants from animals under fasting and exercise training, at pathological situations such as anorexia and obesity, and from human obese individuals were assayed by immunoblotting, quantitative real-time polymerase chain reaction and enzyme-linked immunosorbent assay. We reveal that visceral adipose tissue expresses and secretes more alpha-2-Heremans-Schmid glycoprotein than subcutaneous adipose tissue, and that this secretion is diminished after fasting and exercise training. Visceral adipose tissue from anorectic animals showed reduced alpha-2-Heremans-Schmid glycoprotein secretion; on the contrary, alpha-2-Heremans-Schmid glycoprotein is over-secreted by visceral adipose tissue in the occurrence of obesity. While secretion of active-PhophoSer321α2HSG by visceral adipose tissue is independent of body mass index, we found that the fraction of active-alpha-2-Heremans-Schmid glycoprotein secreted by subcutaneous adipose tissue increments significantly in situations of obesity. Functional studies show that the inhibition of adipose-derived alpha-2-Heremans-Schmid glycoprotein increases insulin sensitivity in differentiated adipocytes. In conclusion, visceral adipose tissue secretes more alpha-2-Heremans-Schmid glycoprotein than subcutaneous adipose tissue and this secretion is more sensitive to nutritional and physiological changes. The over-secretion of alpha-2-Heremans-Schmid glycoprotein by visceral adipose tissue, the increased secretion of the active phosphorylated form by subcutaneous adipose tissuein obese animals, and the adipose-derived alpha-2-Heremans-Schmid glycoprotein capacity to inhibit the insulin pathway suggest the participation of adipose-derived alpha-2-Heremans-Schmid glycoprotein in the deleterious effects of obesity.

Functional Characterization of Preadipocytes Derived from Human Periaortic Adipose Tissue

PubMed Central

Camacho, Jaime; Duque, Juan; Carreño, Marisol; Acero, Edward; Pérez, Máximo; Ramirez, Sergio; Umaña, Juan; Obando, Carlos; Guerrero, Albert; Sandoval, Néstor; Rodríguez, Gina

2017-01-01

Adipose tissue can affect the metabolic control of the cardiovascular system, and its anatomic location can affect the vascular function differently. In this study, biochemical and phenotypical characteristics of adipose tissue from periaortic fat were evaluated. Periaortic and subcutaneous adipose tissues were obtained from areas surrounding the ascending aorta and sternotomy incision, respectively. Adipose tissues were collected from patients undergoing myocardial revascularization or mitral valve replacement surgery. Morphological studies with hematoxylin/eosin and immunohistochemical assay were performed in situ to quantify adipokine expression. To analyze adipogenic capacity, adipokine expression, and the levels of thermogenic proteins, adipocyte precursor cells were isolated from periaortic and subcutaneous adipose tissues and induced to differentiation. The precursors of adipocytes from the periaortic tissue accumulated less triglycerides than those from the subcutaneous tissue after differentiation and were smaller than those from subcutaneous adipose tissue. The levels of proteins involved in thermogenesis and energy expenditure increased significantly in periaortic adipose tissue. Additionally, the expression levels of adipokines that affect carbohydrate metabolism, such as FGF21, increased significantly in mature adipocytes induced from periaortic adipose tissue. These results demonstrate that precursors of periaortic adipose tissue in humans may affect cardiovascular events and might serve as a target for preventing vascular diseases. PMID:29209367

Efficacy of thigh volume ratios assessed via stereovision body imaging as a predictor of visceral adipose tissue measured by magnetic resonance imaging

PubMed Central

Lee, Jane J; Freeland-Graves, Jeanne H; Pepper, M Reese; Yu, Wurong; Xu, Bugao

2014-01-01

Objectives The research examined the efficacy of regional volumes of thigh ratios assessed by stereovision body imaging (SBI) as a predictor of visceral adipose tissue measured by magnetic resonance imaging (MRI). Body measurements obtained via SBI also were utilized to explore disparities of body size and shape in men and women. Method 121 participants were measured for total/regional body volumes and ratios via SBI and abdominal subcutaneous and visceral adipose tissue areas by MRI. Results Thigh to torso and thigh to abdomen-hip volume ratios were the most reliable parameters to predict the accumulation of visceral adipose tissue depots compared to other body measurements. Thigh volume in relation to torso [odds ratios (OR) 0.44] and abdomen-hip (OR 0.41) volumes were negatively associated with increased risks of greater visceral adipose tissue depots, even after controlling for age, gender, and body mass index (BMI). Irrespective of BMI classification, men exhibited greater total body (80.95L vs. 72.41L), torso (39.26L vs. 34.13L), and abdomen-hip (29.01L vs. 25.85L) volumes than women. Women had higher thigh volumes (4.93L vs. 3.99L) and lower-body volume ratios [thigh to total body (0.07 vs. 0.05), thigh to torso (0.15 vs. 0.11), and thigh to abdomen-hip (0.20 vs. 0.15); p<0.05]. Conclusions The unique parameters of the volumes of thigh in relation to torso and abdomen-hip, by SBI were highly effective in predicting visceral adipose tissue deposition. The SBI provided an efficient method for determining body size and shape in men and women via total and regional body volumes and ratios. PMID:25645428

White Adipose Tissue Is a Reservoir for Memory T Cells and Promotes Protective Memory Responses to Infection.

PubMed

Han, Seong-Ji; Glatman Zaretsky, Arielle; Andrade-Oliveira, Vinicius; Collins, Nicholas; Dzutsev, Amiran; Shaik, Jahangheer; Morais da Fonseca, Denise; Harrison, Oliver J; Tamoutounour, Samira; Byrd, Allyson L; Smelkinson, Margery; Bouladoux, Nicolas; Bliska, James B; Brenchley, Jason M; Brodsky, Igor E; Belkaid, Yasmine

2017-12-19

White adipose tissue bridges body organs and plays a fundamental role in host metabolism. To what extent adipose tissue also contributes to immune surveillance and long-term protective defense remains largely unknown. Here, we have shown that at steady state, white adipose tissue contained abundant memory lymphocyte populations. After infection, white adipose tissue accumulated large numbers of pathogen-specific memory T cells, including tissue-resident cells. Memory T cells in white adipose tissue expressed a distinct metabolic profile, and white adipose tissue from previously infected mice was sufficient to protect uninfected mice from lethal pathogen challenge. Induction of recall responses within white adipose tissue was associated with the collapse of lipid metabolism in favor of antimicrobial responses. Our results suggest that white adipose tissue represents a memory T cell reservoir that provides potent and rapid effector memory responses, positioning this compartment as a potential major contributor to immunological memory. Published by Elsevier Inc.

Irbesartan increased PPAR{gamma} activity in vivo in white adipose tissue of atherosclerotic mice and improved adipose tissue dysfunction

DOE Office of Scientific and Technical Information (OSTI.GOV)

Iwai, Masaru; Kanno, Harumi; Senba, Izumi

2011-03-04

Research highlights: {yields} Atherosclerotic apolipoprotein E-deficient (ApoEKO) mice were treated with irbesartan. {yields} Irbesartan decreased white adipose tissue weight without affecting body weight. {yields} DNA-binding for PPAR{gamma} was increased in white adipose tissue in vivo by irbesartan. {yields} Irbesartan increased adipocyte number in white adipose tissue. {yields} Irbesatan increased the expression of adiponectin and leptin in white adipose tissue. -- Abstract: The effect of the PPAR{gamma} agonistic action of an AT{sub 1} receptor blocker, irbesartan, on adipose tissue dysfunction was explored using atherosclerotic model mice. Adult male apolipoprotein E-deficient (ApoEKO) mice at 9 weeks of age were treated with amore » high-cholesterol diet (HCD) with or without irbesartan at a dose of 50 mg/kg/day for 4 weeks. The weight of epididymal and retroperitoneal adipose tissue was decreased by irbesartan without changing food intake or body weight. Treatment with irbesartan increased the expression of PPAR{gamma} in white adipose tissue and the DNA-binding activity of PPAR{gamma} in nuclear extract prepared from adipose tissue. The expression of adiponectin, leptin and insulin receptor was also increased by irbesartan. These results suggest that irbesartan induced activation of PPAR{gamma} and improved adipose tissue dysfunction including insulin resistance.« less

Culture and Sampling of Primary Adipose Tissue in Practical Microfluidic Systems.

PubMed

Brooks, Jessica C; Judd, Robert L; Easley, Christopher J

2017-01-01

Microfluidic culture of primary adipose tissue allows for reduced sample and reagent volumes as well as constant media perfusion of the cells. By continuously flowing media over the tissue, microfluidic sampling systems can more accurately mimic vascular flow in vivo. Quantitative measurements can be performed on or off chip to provide time-resolved secretion data, furthering insight into the dynamics of the function of adipose tissue. Buoyancy resulting from the large lipid storage capacity in this tissue presents a unique challenge for culture, and it is important to account for this buoyancy during microdevice design. Herein, we describe approaches for microfluidic device fabrication that utilize 3D-printed interface templating to help counteract cell buoyancy. We apply such methods to the culture of both isolated, dispersed primary adipocytes and epididymal adipose explants. To facilitate more widespread adoption of the methodology, the devices presented here are designed for user-friendly operation. Only handheld syringes are needed to control flow, and devices are inexpensive and disposable.

Progress toward automatic classification of human brown adipose tissue using biomedical imaging

NASA Astrophysics Data System (ADS)

Gifford, Aliya; Towse, Theodore F.; Walker, Ronald C.; Avison, Malcom J.; Welch, E. B.

2015-03-01

Brown adipose tissue (BAT) is a small but significant tissue, which may play an important role in obesity and the pathogenesis of metabolic syndrome. Interest in studying BAT in adult humans is increasing, but in order to quantify BAT volume in a single measurement or to detect changes in BAT over the time course of a longitudinal experiment, BAT needs to first be reliably differentiated from surrounding tissue. Although the uptake of the radiotracer 18F-Fluorodeoxyglucose (18F-FDG) in adipose tissue on positron emission tomography (PET) scans following cold exposure is accepted as an indication of BAT, it is not a definitive indicator, and to date there exists no standardized method for segmenting BAT. Consequently, there is a strong need for robust automatic classification of BAT based on properties measured with biomedical imaging. In this study we begin the process of developing an automated segmentation method based on properties obtained from fat-water MRI and PET-CT scans acquired on ten healthy adult subjects.

Association of Changes in Abdominal Fat and Cardiovascular Risk Factors

PubMed Central

Lee, Jane J.; Pedley, Alison; Hoffmann, Udo; Massaro, Joseph M.; Fox, Caroline S.

2017-01-01

BACKGROUND Subcutaneous adipose tissue (SAT) and visceral adipose tissue (VAT) are associated with adverse cardiometabolic risk profiles. OBJECTIVES This study explored the degree to which changes in abdominal fat quantity and quality are associated with changes in cardiovascular disease (CVD) risk factors. METHODS Study participants (n = 1,106; 44.1% women; mean baseline age 45.1 years) were drawn from the Framingham Heart Study Third Generation cohort who participated in the computed tomography (CT) substudy Exams 1 and 2. Participants were followed for 6.1 years on average. Abdominal adipose tissue volume in cm3 and attenuation in Hounsfield units (HU) were determined by CT-acquired abdominal scans. RESULTS The mean fat volume change was an increase of 602 cm3 for SAT and an increase of 703 cm3 for VAT; the mean fat attenuation change was a decrease of 5.5HU for SAT and an increase of 0.07 HU for VAT. An increase in fat volume and decrease in fat attenuation were associated with adverse changes in CVD risk factors. An additional 500 cm3 increase in fat volume was associated with incident hypertension (odds ratio [OR]: 1.21 for SAT; OR: 1.30 for VAT), hypertriglyceridemia (OR: 1.15 for SAT; OR: 1.56 for VAT), and metabolic syndrome (OR: 1.43 for SAT; OR: 1.82 for VAT; all p < 0.05). Similar trends were observed for each additional 5 HU decrease in abdominal adipose tissue attenuation. Most associations remained significant even after further accounting for body mass index change, waist circumference change, or respective abdominal adipose tissue volumes. CONCLUSIONS Increasing accumulation of fat quantity and decreasing fat attenuation are associated with worsening of CVD risk factors beyond the associations with generalized adiposity, central adiposity, or respective adipose tissue volumes. PMID:27687192

Comparative Proteomic Analyses of Human Adipose Extracellular Matrices Decellularized Using Alternative Procedures.

PubMed

Thomas-Porch, Caasy; Li, Jie; Zanata, Fabiana; Martin, Elizabeth C; Pashos, Nicholas; Genemaras, Kaylynn; Poche, J Nicholas; Totaro, Nicholas P; Bratton, Melyssa R; Gaupp, Dina; Frazier, Trivia; Wu, Xiying; Ferreira, Lydia Masako; Tian, Weidong; Wang, Guangdi; Bunnell, Bruce A; Flynn, Lauren; Hayes, Daniel; Gimble, Jeffrey M

2018-04-25

Decellularized human adipose tissue has potential clinical utility as a processed biological scaffold for soft tissue cosmesis, grafting and reconstruction. Adipose tissue decellularization has been accomplished using enzymatic-, detergent-, and/or solvent-based methods. To examine the hypothesis that distinct decellularization processes may yield scaffolds with differing compositions, the current study employed mass spectrometry to compare the proteomes of human adipose-derived matrices generated through three independent methods combining enzymatic-, detergent-, and/or solvent-based steps. In addition to protein content, bioscaffolds were evaluated for DNA depletion, ECM composition, and physical structure using optical density, histochemical staining, and scanning electron microscopy (SEM). Mass spectrometry (MS) based proteomic analyses identified 25 proteins (having at least two peptide sequences detected) in the scaffolds generated with an enzymatic approach, 143 with the detergent approach, and 102 with the solvent approach, as compared to 155 detected in unprocessed native human fat. Immunohistochemical detection confirmed the presence of the structural proteins actin, collagen type VI, fibrillin, laminin, and vimentin. Subsequent in vivo analysis of the predominantly enzymatic- and detergent-based decellularized scaffolds following subcutaneous implantation in GFP + transgenic mice demonstrated that the matrices generated with both approaches supported the ingrowth of host-derived adipocyte progenitors and vasculature in a time dependent manner. Together, these results determine that decellularization methods influence the protein composition of adipose tissue-derived bioscaffolds. This article is protected by copyright. All rights reserved. © 2018 Wiley Periodicals, Inc.

Obesity and Cancer Mechanisms: Tumor Microenvironment and Inflammation.

PubMed

Iyengar, Neil M; Gucalp, Ayca; Dannenberg, Andrew J; Hudis, Clifford A

2016-12-10

Purpose There is growing evidence that inflammation is a central and reversible mechanism through which obesity promotes cancer risk and progression. Methods We review recent findings regarding obesity-associated alterations in the microenvironment and the local and systemic mechanisms through which these changes support tumor growth. Results Locally, hyperadiposity is associated with altered adipose tissue function, adipocyte death, and chronic low-grade inflammation. Most individuals who are obese harbor inflamed adipose tissue, which resembles chronically injured tissue, with immune cell infiltration and remodeling. Within this distinctly altered local environment, several pathophysiologic changes are found that may promote breast and other cancers. Consistently, adipose tissue inflammation is associated with a worse prognosis in patients with breast and tongue cancers. Systemically, the metabolic syndrome, including dyslipidemia and insulin resistance, occurs in the setting of adipose inflammation and operates in concert with local mechanisms to sustain the inflamed microenvironment and promote tumor growth. Importantly, adipose inflammation and its protumor consequences can be found in some individuals who are not considered to be obese or overweight by body mass index. Conclusion The tumor-promoting effects of obesity occur at the local level via adipose inflammation and associated alterations in the microenvironment, as well as systemically via circulating metabolic and inflammatory mediators associated with adipose inflammation. Accurately characterizing the obese state and identifying patients at increased risk for cancer development and progression will likely require more precise assessments than body mass index alone. Biomarkers of adipose tissue inflammation would help to identify high-risk populations. Moreover, adipose inflammation is a reversible process and represents a novel therapeutic target that warrants further study to break the obesity-cancer link.

Aging and Adipose Tissue: Potential Interventions for Diabetes and Regenerative Medicine

PubMed Central

Palmer, Allyson K.; Kirkland, James L.

2016-01-01

Adipose tissue dysfunction occurs with aging and has systemic effects, including peripheral insulin resistance, ectopic lipid deposition, and inflammation. Fundamental aging mechanisms, including cellular senescence and progenitor cell dysfunction, occur in adipose tissue with aging and may serve as potential therapeutic targets in age-related disease. In this review, we examine the role of adipose tissue in healthy individuals and explore how aging leads to adipose tissue dysfunction, redistribution, and changes in gene regulation. Adipose tissue plays a central role in longevity, and interventions restricted to adipose tissue may impact lifespan. Conversely, obesity may represent a state of accelerated aging. We discuss the potential therapeutic potential of targeting basic aging mechanisms, including cellular senescence, in adipose tissue, using type II diabetes and regenerative medicine as examples. We make the case that aging should not be neglected in the study of adipose-derived stem cells for regenerative medicine strategies, as elderly patients make up a large portion of individuals in need of such therapies. PMID:26924669

Comparison of gross body fat-water magnetic resonance imaging at 3 Tesla to dual-energy X-ray absorptiometry in obese women.

PubMed

Silver, Heidi J; Niswender, Kevin D; Kullberg, Joel; Berglund, Johan; Johansson, Lars; Bruvold, Morten; Avison, Malcolm J; Welch, E Brian

2013-04-01

Improved understanding of how depot-specific adipose tissue mass predisposes to obesity-related comorbidities could yield new insights into the pathogenesis and treatment of obesity as well as metabolic benefits of weight loss. We hypothesized that three-dimensional (3D) contiguous "fat-water" MR imaging (FWMRI) covering the majority of a whole-body field of view (FOV) acquired at 3 Tesla (3T) and coupled with automated segmentation and quantification of amount, type, and distribution of adipose and lean soft tissue would show great promise in body composition methodology. Precision of adipose and lean soft tissue measurements in body and trunk regions were assessed for 3T FWMRI and compared to dual-energy X-ray absorptiometry (DXA). Anthropometric, FWMRI, and DXA measurements were obtained in 12 women with BMI 30-39.9 kg/m(2) . Test-retest results found coefficients of variation (CV) for FWMRI that were all under 3%: gross body adipose tissue (GBAT) 0.80%, total trunk adipose tissue (TTAT) 2.08%, visceral adipose tissue (VAT) 2.62%, subcutaneous adipose tissue (SAT) 2.11%, gross body lean soft tissue (GBLST) 0.60%, and total trunk lean soft tissue (TTLST) 2.43%. Concordance correlation coefficients between FWMRI and DXA were 0.978, 0.802, 0.629, and 0.400 for GBAT, TTAT, GBLST, and TTLST, respectively. While Bland-Altman plots demonstrated agreement between FWMRI and DXA for GBAT and TTAT, a negative bias existed for GBLST and TTLST measurements. Differences may be explained by the FWMRI FOV length and potential for DXA to overestimate lean soft tissue. While more development is necessary, the described 3T FWMRI method combined with fully-automated segmentation is fast (<30-min total scan and post-processing time), noninvasive, repeatable, and cost-effective. Copyright © 2012 The Obesity Society.

Strategies for reducing body fat mass: effects of liposuction and exercise on cardiovascular risk factors and adiposity

PubMed Central

Benatti, Fabiana Braga; Lira, Fábio Santos; Oyama, Lila Missae; do Nascimento, Cláudia Maria da Penha Oller; Lancha, Antonio Herbert

2011-01-01

Liposuction is the most popular aesthetic surgery performed in Brazil and worldwide. Evidence showing that adipose tissue is a metabolically active tissue has led to the suggestion that liposuction could be a viable method for improving metabolic profile through the immediate loss of adipose tissue. However, the immediate liposuction-induced increase in the proportion of visceral to subcutaneous adipose tissue could be detrimental to metabolism, because a high proportion of visceral to subcutaneous adipose tissue is associated with risk factors for cardiovascular disease. The results of studies investigating the effects of liposuction on the metabolic profile are inconsistent, however, with most studies reporting either no change or improvements in one or more cardiovascular risk factors. In addition, animal studies have demonstrated a compensatory growth of intact adipose tissue in response to lipectomy, although studies with humans have reported inconsistent results. Exercise training improves insulin sensitivity, inflammatory balance, lipid oxidation, and adipose tissue distribution; increases or preserves the fat-free mass; and increases total energy expenditure. Thus, liposuction and exercise appear to directly affect metabolism in similar ways, which suggests a possible interaction between these two strategies. To our knowledge, no studies have reported the associated effects of liposuction and exercise in humans. Nonetheless, one could suggest that exercise training associated with liposuction could attenuate or even block the possible compensatory fat deposition in intact depots or regrowth of the fat mass and exert an additive or even a synergistic effect to liposuction on improving insulin sensitivity and the inflammatory balance, resulting in an improvement of cardiovascular risk factors. Consequently, one could suggest that liposuction and exercise appear to be safe and effective strategies for either the treatment of metabolic disorders or aesthetic purposes. PMID:21779146

Insulin resistance, hepatic lipid and adipose tissue distribution in HIV infected men

PubMed Central

He, Qing; Engelson, Ellen S.; Ionescu, Gabriel; Glesby, Marshall J.; Albu, Jeanine B.; Kotler, Donald P.

2010-01-01

Background A large proportion of HIV-infected subjects on antiretroviral medication develop insulin resistance, especially in the context of fat redistribution. This study investigates the interrelationships among fat distribution, hepatic lipid content, and insulin resistance in HIV-infected men. Design and methods We performed a cross-sectional analysis of baseline data from twenty-three HIV-infected participants in 3 prospective clinical studies. Magnetic resonance spectroscopy was applied to quantify hepatic lipid concentrations. Magnetic resonance imaging was used to quantify whole body adipose tissue compartments, i.e., subcutaneous adipose tissue (SAT) and visceral adipose tissue (VAT) volumes as well as inter-muscular adipose tissue (IMAT) subcompartment, and omental-mesenteric adipose tissue (OMAT) and retroperitoneal adipose tissue (RPAT) subcompartments of VAT. Homeostasis model for assessment of insulin resistance (HOMA-IR) was calculated from fasting glucose and insulin concentrations. Results Hepatic lipid content correlated significantly with total VAT (r=0.62, p=0.0014) but not with SAT (r=0.053, p=0.81). In univariate analysis, hepatic lipid content was associated with the OMAT (r=0.67, p=0.0004) and RPAT (r=0.53, p=0.009) subcompartments; HOMA-IR correlated with both VAT and hepatic lipid contents (r=0.61, p=0.057 and 0.68, p=0.0012, respectively). In stepwise linear regression models, hepatic lipid had the strongest associations with OMAT and with HOMA-IR. Conclusion Hepatic lipid content is associated with VAT volume, especially the omental-mesenteric subcompartment, in HIV-infected men. Hepatic lipid content is associated with insulin resistance in HIV-infected men. Hepatic lipid content might mediate the relationship between VAT and insulin resistance among treated, HIV-infected men. PMID:18572755

Primary Hyperparathyroidism: The Influence of Bone Marrow Adipose Tissue on Bone Loss and of Osteocalcin on Insulin Resistance

PubMed Central

Mendonça, Maira L.; Batista, Sérgio L.; Nogueira-Barbosa, Marcello H.; Salmon, Carlos E.G.; de Paula, Francisco J.A.

2016-01-01

OBJECTIVES: Bone marrow adipose tissue has been associated with low bone mineral density. However, no data exist regarding marrow adipose tissue in primary hyperparathyroidism, a disorder associated with bone loss in conditions of high bone turnover. The objective of the present study was to investigate the relationship between marrow adipose tissue, bone mass and parathyroid hormone. The influence of osteocalcin on the homeostasis model assessment of insulin resistance was also evaluated. METHODS: This was a cross-sectional study conducted at a university hospital, involving 18 patients with primary hyperparathyroidism (PHPT) and 21 controls (CG). Bone mass was assessed by dual-energy x-ray absorptiometry and marrow adipose tissue was assessed by 1H magnetic resonance spectroscopy. The biochemical evaluation included the determination of parathyroid hormone, osteocalcin, glucose and insulin levels. RESULTS: A negative association was found between the bone mass at the 1/3 radius and parathyroid hormone levels (r = -0.69; p<0.01). Marrow adipose tissue was not significantly increased in patients (CG = 32.8±11.2% vs PHPT = 38.6±12%). The serum levels of osteocalcin were higher in patients (CG = 8.6±3.6 ng/mL vs PHPT = 36.5±38.4 ng/mL; p<0.005), but no associations were observed between osteocalcin and insulin or between insulin and both marrow adipose tissue and bone mass. CONCLUSION: These results suggest that the increment of adipogenesis in the bone marrow microenvironment under conditions of high bone turnover due to primary hyperparathyroidism is limited. Despite the increased serum levels of osteocalcin due to primary hyperparathyroidism, these patients tend to have impaired insulin sensitivity. PMID:27626477

In vivo photoacoustic monitoring of anti-obesity photothermal lipolysis

NASA Astrophysics Data System (ADS)

Lee, Donghyun; Lee, Jung Ho; Hahn, Sei Kwang; Kim, Chulhong

2018-02-01

Obesity with a body mass index is greater than 30 kg/m2 is one of the rapidly growing diseases in advanced societies and can lead to stroke, type 2 diabetes, and heart failure. Common methods of removing subcutaneous adipose tissues are liposuction and laser treatment. In this study, we used photoacoustic imaging to monitor the anti-obesity photothermal degradation process. To improve the photothermal lipid degradation efficiency without any invasive methods, we synthesized hyaluronic acid hollow hold nanosphere adipocyte targeting sequence peptide (HA-HAuNS-ATS) conjugates. The conjugate enhanced the skin penetration ability and biodegradability of the nanoparticles using hyaluronate and enhanced the targeting effect on adipose tissue with adipocyte targeting sequence peptide. Thus, the conjugate can be delivered to the adipose tissue by simply spreading the conjugate on the skin without any invasive method. Then, the photothermal lipolysis and delivery of the conjugate were photoacoustically monitored in vivo. These results demonstrate the potential for photoacoustic method to be applied for photothermal lipolysis monitoring.

Quantification of Adipose Tissue Leukocytosis in Obesity

PubMed Central

Grant, Ryan; Youm, Yun-Hee; Ravussin, Anthony; Dixit, Vishwa Deep

2014-01-01

Summary The infiltration of immune cell subsets in adipose tissue termed ‘adipose tissue leukocytosis’ is a critical event in the development of chronic inflammation and obesity-associated comorbidities. Given that a significant proportion of cells in adipose tissue of obese patients are of hematopoietic lineage, the distinct adipose depots represent an uncharacterized immunological organ that can impact metabolic functions. Here, we describe approaches to characterize and isolate leukocytes from the complex adipose tissue microenvironment to aid mechanistic studies to understand the role of specific pattern recognition receptors (PRRs) such as inflammasomes in adipose-immune crosstalk. PMID:23852606

Adipose Tissue Angiogenesis: Impact on Obesity and Type-2 Diabetes

PubMed Central

Corvera, Silvia; Gealekman, Olga

2013-01-01

The growth and function of tissues is critically dependent on their vascularization. Adipose tissue is capable of expanding many-fold during adulthood, therefore requiring the formation of new vasculature to supply growing and proliferating adipocytes. The expansion of the vasculature in adipose tissue occurs through angiogenesis, where new blood vessels develop from those pre-existing within the tissue. Inappropriate angiogenesis may underlie adipose tissue dysfunction in obesity, which in turn increases type-2 diabetes risk. In addition, genetic and developmental factors involved in vascular patterning may define the size and expandability of diverse adipose tissue depots, which are also associated with type-2 diabetes risk. Moreover, the adipose tissue vasculature appears to be the niche for pre-adipocyte precursors, and factors that affect angiogenesis may directly impact the generation of new adipocytes. Here we review recent advances on the basic mechanisms of angiogenesis, and on the role of angiogenesis in adipose tissue development and obesity. A substantial amount of data point to a deficit in adipose tissue angiogenesis as a contributing factor to insulin resistance and metabolic disease in obesity. These emerging findings support the concept of the adipose tissue vasculature as a source of new targets for metabolic disease therapies. PMID:23770388

The Adipose Renin-Angiotensin System Modulates Systemic Markers of Insulin Sensitivity and Activates the Intrarenal Renin-Angiotensin System

DOE PAGES

Kim, Suyeon; Soltani-Bejnood, Morvarid; Quignard-Boulange, Annie; ...

2006-01-01

Background . The adipose tissue renin-angiotensin system (RAS) contributes to regulation of fat mass and may also impact systemic functions such as blood pressure and metabolism. Methods and results . A panel of mouse models including mice lacking angiotensinogen, Agt ( Agt -KO), mice expressing Agt solely in adipose tissue (aP2- Agt/Agt -KO), and mice overexpressing Agt in adipose tissue (aP2- Agt ) was studied. Total body weight, epididymal fat pad weight, and circulating levels of leptin, insulin, and resistin were significantly decreased in Agt -KO mice, while plasma adiponectin levels were increased. aP2- Agt mice exhibited increased adiposity andmore » plasma leptin and insulin levels compared to wild type (WT) controls. Angiotensinogen and type I Ang II receptor protein levels were also elevated in kidney of aP2- Agt mice. Conclusion . These findings demonstrate that alterations in adipose RAS activity significantly impact both local and systemic physiology in a way that may contribute to the detrimental health effects of obesity.« less

The development and endocrine functions of adipose tissue

USDA-ARS?s Scientific Manuscript database

White adipose tissue is a mesenchymal tissue that begins developing in the fetus. Classically known for storing the body’s fuel reserves, adipose tissue is now recognized as an endocrine organ. As such, the secretions from adipose tissue are known to affect several systems such as the vascular and...

The effect of diabetes on the wound healing potential of adipose-tissue derived stem cells.

PubMed

Kim, Sue Min; Kim, Yun Ho; Jun, Young Joon; Yoo, Gyeol; Rhie, Jong Won

2016-03-01

To investigate whether diabetes mellitus affects the wound-healing-promoting potential of adipose tissue-derived stem cells, we designed a wound-healing model using diabetic mice. We compared the degree of wound healing between wounds treated with normal adipose tissue-derived stem cells and wounds treated with diabetic adipose tissue-derived stem cells. We evaluated the wound-healing rate, the epithelial tongue distance, the area of granulation tissue, the number of capillary and the number of Ki-67-stained cells. The wound-healing rate was significantly higher in the normal adipose tissue-derived stem cells group than in the diabetic adipose tissue-derived stem cells group; it was also significantly higher in the normal adipose tissue-derived stem cells group than in the control group. Although the diabetic adipose tissue-derived stem cells group showed a better wound-healing rate than the control group, the difference was not statistically significant. Similar trends were observed for the other parameters examined: re-epithelisation and keratinocyte proliferation; granulation tissue formation; and dermal regeneration. However, with regard to the number of capillary, diabetic adipose tissue-derived stem cells retained their ability to promote neovasculisation and angiogenesis. These results reflect the general impairment of the therapeutic potential of diabetic adipose tissue-derived stem cells in vivo. © 2016 Medicalhelplines.com Inc and John Wiley & Sons Ltd.

Application of a novel sorting system for equine mesenchymal stem cells (MSCs)

PubMed Central

Radtke, Catherine L.; Nino-Fong, Rodolfo; Esparza Gonzalez, Blanca P.; McDuffee, Laurie A.

2014-01-01

The objective of this study was to validate non-equilibrium gravitational field-flow fractionation (GrFFF), an immunotag-less method of sorting mesenchymal stem cells (MSCs) into subpopulations, for use with MSCs derived from equine muscle tissue, periosteal tissue, bone marrow, and adipose tissue. Cells were collected from 6 young, adult horses, postmortem. Cells were isolated from left semitendinosus muscle tissue, periosteal tissue from the distomedial aspect of the right tibia, bone marrow aspirates from the fourth and fifth sternebrae, and left supragluteal subcutaneous adipose tissue. Aliquots of 800 × 103 MSCs from each tissue source were separated and injected into a ribbon-like capillary device by continuous flow (GrFFF proprietary system). Cells were sorted into 6 fractions and absorbencies [optical density (OD)] were read. Six fractions from each of the 6 aliquots were then combined to provide pooled fractions that had adequate cell numbers to seed at equal concentrations into assays. Equine muscle tissue-derived, periosteal tissue-derived, bone marrow-derived, and adipose tissue-derived mesenchymal stem cells were consistently sorted into 6 fractions that remained viable for use in further assays. Fraction 1 had more cuboidal morphology in culture when compared to the other fractions. Statistical analysis of the fraction absorbencies (OD) revealed a P-value of < 0.05 when fractions 2 and 3 were compared to fractions 1, 4, 5, and 6. It was concluded that non-equilibrium GrFFF is a valid method for sorting equine muscle tissue-derived, periosteal tissue-derived, bone marrow-derived, and adipose tissue-derived mesenchymal stem cells into subpopulations that remain viable, thus securing its potential for use in equine stem cell applications and veterinary medicine. PMID:25355998

Increased Adipocyte Size, Macrophage Infiltration, and Adverse Local Adipokine Profile in Perirenal Fat in Cushing's Syndrome.

PubMed

Roerink, Sean H P P; Wagenmakers, Margreet A E M; Langenhuijsen, Johan F; Ballak, Dov B; Rooijackers, Hanne M M; d'Ancona, Frank C; van Dielen, François M; Smit, Jan W A; Plantinga, Theo S; Netea-Maier, Romana T; Hermus, Ad R M M

2017-08-01

To analyze changes in fat cell size, macrophage infiltration, and local adipose tissue adipokine profiles in different fat depots in patients with active Cushing's syndrome. Subcutaneous (SC) and perirenal (PR) adipose tissue of 10 patients with Cushing's syndrome was compared to adipose tissue of 10 gender-, age-, and BMI-matched controls with regard to adipocyte size determined by digital image analysis on hematoxylin and eosin stainings, macrophage infiltration determined by digital image analysis on CD68 stainings, and adipose tissue leptin and adiponectin levels using fluorescent bead immunoassays and ELISA techniques. Compared to the controls, mean adipocyte size was larger in PR adipose tissue in patients. The percentage of macrophage infiltration of the PR adipose tissue and PR adipose tissue lysate leptin levels were higher and adiponectin levels were lower in SC and PR adipose tissue lysates in patients. The adiponectin levels were also lower in the SC adipose tissue supernatants of patients. Associations were found between the severity of hypercortisolism and PR adipocyte size. Cushing's syndrome is associated with hypertrophy of PR adipocytes and a higher percentage of macrophage infiltration in PR adipose tissue. These changes are associated with an adverse local adipokine profile. © 2017 The Obesity Society.

Thermogenic profiling using magnetic resonance imaging of dermal and other adipose tissues

PubMed Central

Kasza, Ildiko; Hernando, Diego; Roldán-Alzate, Alejandro; Alexander, Caroline M.; Reeder, Scott B.

2016-01-01

Dermal white adipose tissue (dWAT) was recently recognized for its potential to modify whole body metabolism. Here, we show that dWAT can be quantified using a high-resolution, fat-specific magnetic resonance imaging (MRI) technique. Noninvasive MRI has been used to describe adipocyte depots for many years; the MRI technique we describe uses an advanced fat-specific method to measure the thickness of dWAT, together with the total volume of WAT and the relative activation/fat depletion of brown adipose tissues (BAT). Since skin-embedded adipocytes may provide natural insulation, they provide an important counterpoint to the activation of thermogenic brown and beige adipose tissues, whereby these distinct depots are functionally interrelated and require simultaneous assay. This method was validated using characterized mouse cohorts of a lipodystrophic, dWAT-deficient strain (syndecan-1 KO) and 2 obese models (diet-induced obese mice and genetically obese animals, ob/ob). Using a preliminary cohort of normal human subjects, we found the thickness of skin-associated fat varied 8-fold, from 0.13–1.10 cm; on average, this depot is calculated to weigh 8.8 kg. PMID:27668285

Regulation of Small Ubiquitin-Like Modifier-1, Nuclear Receptor Coreceptor, Histone Deacetylase 3, and Peroxisome Proliferator-Activated Receptor-γ in Human Adipose Tissue

PubMed Central

Bodles-Brakhop, Angela M.; Yao-Borengasser, Aiwei; Zhu, Beibei; Starnes, Catherine P.; McGehee, Robert E.; Peterson, Charlotte A.; Kern, Philip A.

2012-01-01

Abstract Background This study investigated the regulation of peroxisome proliferator-activated receptor-γ (PPARγ), the histone deacetylase 3 (HDAC3)–nuclear receptor coreceptor (NCoR) complex (a corepressor of transcription used by PPARγ), and small ubiquitin-like modifier-1 (SUMO-1) (a posttranslational modifier of PPARγ) in human adipose tissue and both adipocyte and macrophage cell lines. The objective was to determine whether there were alterations in the human adipose tissue gene expression levels of PPARγ, HDAC3, NCoR, and SUMO-1 associated either with obesity or with treatment of impaired glucose tolerance (IGT) subjects with insulin-sensitizing medications. Methods We obtained subcutaneous adipose tissue biopsies from 86 subjects with a wide range of body mass index (BMI) and insulin sensitivity (SI). Additionally, adipose tissue biopsies were obtained from a randomized subgroup of IGT subjects before and after 10 weeks of treatment with either pioglitazone or metformin. Results The adipose mRNA levels of PPARγ, NCoR, HDAC3, and SUMO-1 correlated strongly with each other (P<0.0001); however, SUMO-1, NCoR, and HDAC3 gene expression were not significantly associated with BMI or SI. Pioglitazone increased SUMO-1 expression by 23% (P<0.002) in adipose tissue and an adipocyte cell line (P<0.05), but not in macrophages. Small interfering RNA (siRNA)-mediated knockdown of SUMO-1 decreased PPARγ, HDAC3, and NCoR in THP-1 cells and increased tumor necrosis factor-α (TNF-α) induction in response to lipopolysaccharide (LPS). Conclusions These results suggest that the coordinate regulation of SUMO-1, PPARγ1/2, HDAC3, and NCoR may be more tightly controlled in macrophages than in adipocytes in human adipose and that these modulators of PPARγ activity may be particularly important in the negative regulation of macrophage-mediated adipose inflammation by pioglitazone. PMID:22651256

Assessing the effect of a high-fat diet on rodents' adipose tissue using Brillouin and Raman spectroscopy

NASA Astrophysics Data System (ADS)

Troyanova-Wood, Maria; Gobbell, Cassidy; Meng, Zhaokai; Yakovlev, Vladislav V.

2016-03-01

The purpose of this study is to evaluate the effect of a high-lipid diet on elasticity of adipose tissue. We employed dual Raman/Brillouin microspectroscopy to analyze brown and white adipose tissues obtained from adult rats. The rats were divided into two groups, one of which received a high-fat feed, while the other served as a control. We hypothesized that the changes in the elasticity of adipose tissues between the two groups can be successfully assessed using Brillouin spectroscopy. We found that the brown adipose tissue possessed a lesser Brillouin shift than the white adipose within each group and that the elastic modulus of both adipose tissues increases in the high-fat diet group. The Raman spectra provided supplementary chemical information and indicated an increase in the lipid-to-protein ratio in the brown adipose, but not in the white adipose.

Global gene expression profiling of brown to white adipose tissue transformation in sheep reveals novel transcriptional components linked to adipose remodeling.

PubMed

Basse, Astrid L; Dixen, Karen; Yadav, Rachita; Tygesen, Malin P; Qvortrup, Klaus; Kristiansen, Karsten; Quistorff, Bjørn; Gupta, Ramneek; Wang, Jun; Hansen, Jacob B

2015-03-19

Large mammals are capable of thermoregulation shortly after birth due to the presence of brown adipose tissue (BAT). The majority of BAT disappears after birth and is replaced by white adipose tissue (WAT). We analyzed the postnatal transformation of adipose in sheep with a time course study of the perirenal adipose depot. We observed changes in tissue morphology, gene expression and metabolism within the first two weeks of postnatal life consistent with the expected transition from BAT to WAT. The transformation was characterized by massively decreased mitochondrial abundance and down-regulation of gene expression related to mitochondrial function and oxidative phosphorylation. Global gene expression profiling demonstrated that the time points grouped into three phases: a brown adipose phase, a transition phase and a white adipose phase. Between the brown adipose and the transition phase 170 genes were differentially expressed, and 717 genes were differentially expressed between the transition and the white adipose phase. Thirty-eight genes were shared among the two sets of differentially expressed genes. We identified a number of regulated transcription factors, including NR1H3, MYC, KLF4, ESR1, RELA and BCL6, which were linked to the overall changes in gene expression during the adipose tissue remodeling. Finally, the perirenal adipose tissue expressed both brown and brite/beige adipocyte marker genes at birth, the expression of which changed substantially over time. Using global gene expression profiling of the postnatal BAT to WAT transformation in sheep, we provide novel insight into adipose tissue plasticity in a large mammal, including identification of novel transcriptional components linked to adipose tissue remodeling. Moreover, our data set provides a useful resource for further studies in adipose tissue plasticity.

Insulin and Metformin Regulate Circulating and Adipose Tissue Chemerin

PubMed Central

Tan, Bee K.; Chen, Jing; Farhatullah, Syed; Adya, Raghu; Kaur, Jaspreet; Heutling, Dennis; Lewandowski, Krzysztof C.; O'Hare, J. Paul; Lehnert, Hendrik; Randeva, Harpal S.

2009-01-01

OBJECTIVE To assess chemerin levels and regulation in sera and adipose tissue from women with polycystic ovary syndrome (PCOS) and matched control subjects. RESEARCH DESIGN AND METHODS Real-time RT-PCR and Western blotting were used to assess mRNA and protein expression of chemerin. Serum chemerin was measured by enzyme-linked immunosorbent assay. We investigated the in vivo effects of insulin on serum chemerin levels via a prolonged insulin-glucose infusion. Ex vivo effects of insulin, metformin, and steroid hormones on adipose tissue chemerin protein production and secretion into conditioned media were assessed by Western blotting and enzyme-linked immunosorbent assay, respectively. RESULTS Serum chemerin, subcutaneous, and omental adipose tissue chemerin were significantly higher in women with PCOS (n = 14; P < 0.05, P < 0.01). Hyperinsulinemic induction in human subjects significantly increased serum chemerin levels (n = 6; P < 0.05, P < 0.01). In adipose tissue explants, insulin significantly increased (n = 6; P < 0.05, P < 0.01) whereas metformin significantly decreased (n = 6; P < 0.05, P < 0.01) chemerin protein production and secretion into conditioned media, respectively. After 6 months of metformin treatment, there was a significant decrease in serum chemerin (n = 21; P < 0.01). Importantly, changes in homeostasis model assessment–insulin resistance were predictive of changes in serum chemerin (P = 0.046). CONCLUSIONS Serum and adipose tissue chemerin levels are increased in women with PCOS and are upregulated by insulin. Metformin treatment decreases serum chemerin in these women. PMID:19502420

Automatic segmentation of abdominal organs and adipose tissue compartments in water-fat MRI: Application to weight-loss in obesity.

PubMed

Shen, Jun; Baum, Thomas; Cordes, Christian; Ott, Beate; Skurk, Thomas; Kooijman, Hendrik; Rummeny, Ernst J; Hauner, Hans; Menze, Bjoern H; Karampinos, Dimitrios C

2016-09-01

To develop a fully automatic algorithm for abdominal organs and adipose tissue compartments segmentation and to assess organ and adipose tissue volume changes in longitudinal water-fat magnetic resonance imaging (MRI) data. Axial two-point Dixon images were acquired in 20 obese women (age range 24-65, BMI 34.9±3.8kg/m(2)) before and after a four-week calorie restriction. Abdominal organs, subcutaneous adipose tissue (SAT) compartments (abdominal, anterior, posterior), SAT regions along the feet-head direction and regional visceral adipose tissue (VAT) were assessed by a fully automatic algorithm using morphological operations and a multi-atlas-based segmentation method. The accuracy of organ segmentation represented by Dice coefficients ranged from 0.672±0.155 for the pancreas to 0.943±0.023 for the liver. Abdominal SAT changes were significantly greater in the posterior than the anterior SAT compartment (-11.4%±5.1% versus -9.5%±6.3%, p<0.001). The loss of VAT that was not located around any organ (-16.1%±8.9%) was significantly greater than the loss of VAT 5cm around liver, left and right kidney, spleen, and pancreas (p<0.05). The presented fully automatic algorithm showed good performance in abdominal adipose tissue and organ segmentation, and allowed the detection of SAT and VAT subcompartments changes during weight loss. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

Exosome-Like Vesicles Derived from Adipose Tissue Provide Biochemical Cues for Adipose Tissue Regeneration.

PubMed

Dai, Minjia; Yu, Mei; Zhang, Yan; Tian, Weidong

2017-11-01

There is an emerging need for soft tissue replacements in the field of reconstructive surgery for the treatment of congenital deformities, posttraumatic repair, and cancer rehabilitation. Previous studies have shown that the bioactive adipose tissue extract can induce adipogenesis without additional stem cells or growth factors. In this study, we innovatively investigated whether exosome-like vesicles derived from adipose tissue (ELV-AT) could direct stem cell differentiation and trigger adipose tissue regeneration. In vitro, ELV-AT can induce adipogenesis of adipose-derived stem cells and promote proliferation, migration, and angiogenic potential of the aorta endothelial cells. In vivo, ELV-AT were transplanted to a chamber on the back of nude mice and neoadipose tissues were formed. Our findings indicated that ELV-AT could be used as a cell-free therapeutic approach for adipose tissue regeneration.

PVAT and Its Relation to Brown, Beige, and White Adipose Tissue in Development and Function

PubMed Central

Hildebrand, Staffan; Stümer, Jasmin; Pfeifer, Alexander

2018-01-01

Adipose tissue is commonly categorized into three types with distinct functions, phenotypes, and anatomical localizations. White adipose tissue (WAT) is the major energy store; the largest depots of WAT are found in subcutaneous or intravisceral sites. Brown adipose tissue (BAT) is responsible for energy dissipation during cold-exposure (i.e., non-shivering thermogenesis) and is primarily located in the interscapular region. Beige or brite (brown-in-white) adipose tissue can be found interspersed in WAT and can attain a brown-like phenotype. These three types of tissues also have endocrine functions and play major roles in whole body metabolism especially in obesity and its co-morbidities, such as cardiovascular disease. Over the last years, perivascular adipose tissue (PVAT) has emerged as an adipose organ with endocrine and paracrine functions. Pro and anti-inflammatory agents released by PVAT affect vascular health, and are implicated in the inflammatory aspects of atherosclerosis. PVAT shares several of the defining characteristics of brown adipose tissue, including its cellular morphology and expression of thermogenic genes characteristic for brown adipocytes. However, PVATs from different vessels are phenotypically different, and significant developmental differences exist between PVAT and other adipose tissues. Whether PVAT represents classical BAT, beige adipose tissue, or WAT with changing characteristics, is unclear. In this review, we summarize the current knowledge on how PVAT relates to other types of adipose tissue, both in terms of functionality, developmental origins, and its role in obesity-related cardiovascular disease and inflammation. PMID:29467675

Effect of the anatomical site on telomere length and pref-1 gene expression in bovine adipose tissues

DOE Office of Scientific and Technical Information (OSTI.GOV)

Yamada, Tomoya, E-mail: toyamada@affrc.go.jp; Higuchi, Mikito; Nakanishi, Naoto

Adipose tissue growth is associated with preadipocyte proliferation and differentiation. Telomere length is a biological marker for cell proliferation. Preadipocyte factor-1 (pref-1) is specifically expressed in preadipocytes and acts as a molecular gatekeeper of adipogenesis. In the present study, we investigated the fat depot-specific differences in telomere length and pref-1 gene expression in various anatomical sites (subcutaneous, intramuscular and visceral) of fattening Wagyu cattle. Visceral adipose tissue expressed higher pref-1 mRNA than did subcutaneous and intramuscular adipose tissues. The telomere length in visceral adipose tissue tended to be longer than that of subcutaneous and intramuscular adipose tissues. The telomere lengthmore » of adipose tissue was not associated with adipocyte size from three anatomical sites. No significant correlation was found between the pref-1 mRNA level and the subcutaneous adipocyte size. In contrast, the pref-1 mRNA level was negatively correlated with the intramuscular and visceral adipocyte size. These results suggest that anatomical sites of adipose tissue affect the telomere length and expression pattern of the pref-1 gene in a fat depot-specific manner. - Highlights: • Visceral adipose tissue express higher pref-1 mRNA than other anatomical sites. • Telomere length in visceral adipose tissue is longer than other anatomical sites. • Telomere length of adipose tissue is not associated with adipocyte size. • Pref-1 mRNA is negatively correlated with intramuscular and visceral adipocyte size.« less

A fat option for the pig: Hepatocytic differentiated mesenchymal stem cells for translational research

DOE Office of Scientific and Technical Information (OSTI.GOV)

Brückner, Sandra, E-mail: sandra.brueckner@medizin.uni-leipzig.de; Tautenhahn, Hans-Michael, E-mail: hans-michael.tautenhahn@medizin.uni-leipzig.de; TRM, Translational Centre for Regenerative Medicine, Philipp-Rosenthal-Str. 55, Leipzig D-04103

Study background: Extended liver resection is the only curative treatment option of liver cancer. Yet, the residual liver may not accomplish the high metabolic and regenerative capacity needed, which frequently leads to acute liver failure. Because of their anti-inflammatory and -apoptotic as well as pro-proliferative features, mesenchymal stem cells differentiated into hepatocyte-like cells might provide functional and regenerative compensation. Clinical translation of basic research requires pre-clinical approval in large animals. Therefore, we characterized porcine mesenchymal stem cells (MSC) from adipose tissue and bone marrow and their hepatocyte differentiation potential for future assessment of functional liver support after surgical intervention inmore » the pig model. Methods: Mesenchymal surface antigens and multi-lineage differentiation potential of porcine MSC isolated by collagenase digestion either from bone marrow or adipose tissue (subcutaneous/visceral) were assessed by flow cytometry. Morphology and functional properties (urea-, glycogen synthesis and cytochrome P450 activity) were determined during culture under differentiation conditions and compared with primary porcine hepatocytes. Results: MSC from porcine adipose tissue and from bone marrow express the typical mesenchymal markers CD44, CD29, CD90 and CD105 but not haematopoietic markers. MSC from both sources displayed differentiation into the osteogenic as well as adipogenic lineage. After hepatocyte differentiation, expression of CD105 decreased significantly and cells adopted the typical polygonal morphology of hepatocytes. Glycogen storage was comparable in adipose tissue- and bone marrow-derived cells. Urea synthesis was about 35% lower in visceral than in subcutaneous adipose tissue-derived MSC. Cytochrome P450 activity increased significantly during differentiation and was twice as high in hepatocyte-like cells generated from bone marrow as from adipose tissue. Conclusion: The hepatocyte differentiation of porcine adipose tissue-derived MSC was shown for the first time yielding hepatocyte-like cells with specific functions similar in bone marrow and subcutaneous adipose tissue-derived MSC. That makes them good pre-clinical candidates for supportive approaches after liver resection in the pig. - Highlights: • First time to show hepatocytic differentiation of porcine adipose tissue-derived MSC. • Hepatocytic-differentiated MSC display metabolic qualities of primary hepatocytes. • Metabolic potency varies between differentiated MSC from different tissues. • MSC are good candidates for pre-clinical evaluation of stem cell-based therapies.« less

Abalation of ghrelin receptor reduces adiposity and improves insulin sensitivity during aging by regulating fat metabolism in white and brown adipose tissues

USDA-ARS?s Scientific Manuscript database

Aging is associated with increased adiposity in white adipose tissues and impaired thermogenesis in brown adipose tissues; both contribute to increased incidences of obesity and type 2 diabetes. Ghrelin is the only known circulating orexigenic hormone that promotes adiposity. In this study, we show ...

Aging and adipose tissue: potential interventions for diabetes and regenerative medicine.

PubMed

Palmer, Allyson K; Kirkland, James L

2016-12-15

Adipose tissue dysfunction occurs with aging and has systemic effects, including peripheral insulin resistance, ectopic lipid deposition, and inflammation. Fundamental aging mechanisms, including cellular senescence and progenitor cell dysfunction, occur in adipose tissue with aging and may serve as potential therapeutic targets in age-related disease. In this review, we examine the role of adipose tissue in healthy individuals and explore how aging leads to adipose tissue dysfunction, redistribution, and changes in gene regulation. Adipose tissue plays a central role in longevity, and interventions restricted to adipose tissue may impact lifespan. Conversely, obesity may represent a state of accelerated aging. We discuss the potential therapeutic potential of targeting basic aging mechanisms, including cellular senescence, in adipose tissue, using type II diabetes and regenerative medicine as examples. We make the case that aging should not be neglected in the study of adipose-derived stem cells for regenerative medicine strategies, as elderly patients make up a large portion of individuals in need of such therapies. Copyright © 2016 The Authors. Published by Elsevier Inc. All rights reserved.

Metabolism of 14C-dehydroepiandrosterone in female adipose tissue and venous blood.

PubMed

Schindler, A E; Aymar, M

1975-09-01

The metabolism of dehydroepiandrosterone in female adipose tissue and venous blood in 11 patients was studied by a double isotope method which is described in detail. The main metabolite isolated, identified and quantitated was androstenediol. The conversion rate of dehydroepiandrosterone to androstenediol for adipose tissue ranged between 3.32-14.28% (X = 7.47 +/- 3.34 SD) and for venous blood between 2.88-9.60% (X = 5.84 +/- 1.80 SD). The values found for androstenedione and testostrone did not differ from the control experiments. Oestrone and oestradiol could not be detected. The contribution of the peripheral steroid metabolism to the pool of androgenic steroids is discussed.

Adipose extracellular matrix remodelling in obesity and insulin resistance☆

PubMed Central

Lin, De; Chun, Tae-Hwa; Kang, Li

2016-01-01

The extracellular matrix (ECM) of adipose tissues undergoes constant remodelling to allow adipocytes and their precursor cells to change cell shape and function in adaptation to nutritional cues. Abnormal accumulation of ECM components and their modifiers in adipose tissues has been recently demonstrated to cause obesity-associated insulin resistance, a hallmark of type 2 diabetes. Integrins and other ECM receptors (e.g. CD44) that are expressed in adipose tissues have been shown to regulate insulin sensitivity. It is well understood that a hypoxic response is observed in adipose tissue expansion during obesity progression and that hypoxic response accelerates fibrosis and inflammation in white adipose tissues. The expansion of adipose tissues should require angiogenesis; however, the excess deposition of ECM limits the angiogenic response of white adipose tissues in obesity. While recent studies have focused on the metabolic consequences and the mechanisms of adipose tissue expansion and remodelling, little attention has been paid to the role played by the interaction between peri-adipocyte ECM and their cognate cell surface receptors. This review will address what is currently known about the roles played by adipose ECM, their modifiers, and ECM receptors in obesity and insulin resistance. Understanding how excess ECM deposition in the adipose tissue deteriorates insulin sensitivity would provide us hints to develop a new therapeutic strategy for the treatment of insulin resistance and type 2 diabetes. PMID:27179976

Adipose veno-lymphatic transfer for management of post-radiation lymphedema

DOE Office of Scientific and Technical Information (OSTI.GOV)

Pho, R.W.; Bayon, P.; Tan, L.

1989-01-01

In a patient who had post-radiation lymphedema after excision of liposarcoma, a method is described that is called adipose veno-lymphatic transfer. The technique involves transferring adipose tissue containing lymphatic vessels that surround the long saphenous vein, from the normal, healthy leg to the irradiated leg, with the creation of an arteriovenous fistula.

[Role of chronic inflammation in adipose tissue in the pathophysiology of obesity].

PubMed

Suganami, Takayoshi; Ogawa, Yoshihiro

2013-02-01

Obesity may be viewed as a chronic low-grade inflammatory disease as well as a metabolic disease. Evidence has accumulated suggesting that chronic inflammation in adipose tissue leads to dramatic changes in number and cell type of stromal cells during the course of obesity, which is referred to as"adipose tissue remodeling". Among stromal cells, macrophages in obese adipose tissue are considered to be crucial for adipose tissue inflammation, which results in dysregulated adipocytokine production and ectopic fat accumulation. Understanding the molecular mechanism underlying adipose tissue inflammation would contribute to the identification of novel therapeutic strategies to prevent or treat obesity-induced metabolic derangements.

Purification of human adipose-derived stem cells from fat tissues using PLGA/silk screen hybrid membranes.

PubMed

Chen, Da-Chung; Chen, Li-Yu; Ling, Qing-Dong; Wu, Meng-Hsueh; Wang, Ching-Tang; Suresh Kumar, S; Chang, Yung; Munusamy, Murugan A; Alarfajj, Abdullah A; Wang, Han-Chow; Hsu, Shih-Tien; Higuchi, Akon

2014-05-01

The purification of human adipose-derived stem cells (hADSCs) from human adipose tissue cells (stromal vascular fraction) was investigated using membrane filtration through poly(lactide-co-glycolic acid)/silk screen hybrid membranes. Membrane filtration methods are attractive in regenerative medicine because they reduce the time required to purify hADSCs (i.e., less than 30 min) compared with conventional culture methods, which require 5-12 days. hADSCs expressing the mesenchymal stem cell markers CD44, CD73, and CD90 were concentrated in the permeation solution from the hybrid membranes. Expression of the surface markers CD44, CD73, and CD99 on the cells in the permeation solution from the hybrid membranes, which were obtained using 18 mL of feed solution containing 50 × 10⁴ cells, was statistically significantly higher than that of the primary adipose tissue cells, indicating that the hADSCs can be purified in the permeation solution by the membrane filtration method. Cells expressing the stem cell-associated marker CD34 could be successfully isolated in the permeation solution, whereas CD34⁺ cells could not be purified by the conventional culture method. The hADSCs in the permeation solution demonstrated a superior capacity for osteogenic differentiation based on their alkali phosphatase activity, their osterix gene expression, and the results of mineralization analysis by Alizarin Red S and von Kossa staining compared with the cells from the suspension of human adipose tissue. These results suggest that the hADSCs capable of osteogenic differentiation preferentially permeate through the hybrid membranes. Copyright © 2014 Elsevier Ltd. All rights reserved.

Contribution of Adipose Tissue to Development of Cancer

PubMed Central

Cozzo, Alyssa J.; Fuller, Ashley M.; Makowski, Liza

2018-01-01

Solid tumor growth and metastasis require the interaction of tumor cells with the surrounding tissue, leading to a view of tumors as tissue-level phenomena rather than exclusively cell-intrinsic anomalies. Due to the ubiquitous nature of adipose tissue, many types of solid tumors grow in proximate or direct contact with adipocytes and adipose-associated stromal and vascular components, such as fibroblasts and other connective tissue cells, stem and progenitor cells, endothelial cells, innate and adaptive immune cells, and extracellular signaling and matrix components. Excess adiposity in obesity both increases risk of cancer development and negatively influences prognosis in several cancer types, in part due to interaction with adipose tissue cell populations. Herein, we review the cellular and noncellular constituents of the adipose “organ,” and discuss the mechanisms by which these varied microenvironmental components contribute to tumor development, with special emphasis on obesity. Due to the prevalence of breast and prostate cancers in the United States, their close anatomical proximity to adipose tissue depots, and their complex epidemiologic associations with obesity, we particularly highlight research addressing the contribution of adipose tissue to the initiation and progression of these cancer types. Obesity dramatically modifies the adipose tissue microenvironment in numerous ways, including induction of fibrosis and angiogenesis, increased stem cell abundance, and expansion of proinflammatory immune cells. As many of these changes also resemble shifts observed within the tumor microenvironment, proximity to adipose tissue may present a hospitable environment to developing tumors, providing a critical link between adiposity and tumorigenesis. PMID:29357128

Neural Stem Cells Derived Directly from Adipose Tissue.

PubMed

Petersen, Eric D; Zenchak, Jessica R; Lossia, Olivia V; Hochgeschwender, Ute

2018-05-01

Neural stem cells (NSCs) are characterized as self-renewing cell populations with the ability to differentiate into the multiple tissue types of the central nervous system. These cells can differentiate into mature neurons, astrocytes, and oligodendrocytes. This category of stem cells has been shown to be a promisingly effective treatment for neurodegenerative diseases and neuronal injury. Most treatment studies with NSCs in animal models use embryonic brain-derived NSCs. This approach presents both ethical and feasibility issues for translation to human patients. Adult tissue is a more practical source of stem cells for transplantation therapies in humans. Some adult tissues such as adipose tissue and bone marrow contain a wide variety of stem cell populations, some of which have been shown to be similar to embryonic stem cells, possessing many pluripotent properties. Of these stem cell populations, some are able to respond to neuronal growth factors and can be expanded in vitro, forming neurospheres analogous to cells harvested from embryonic brain tissue. In this study, we describe a method for the collection and culture of cells from adipose tissue that directly, without going through intermediates such as mesenchymal stem cells, results in a population of NSCs that are able to be expanded in vitro and be differentiated into functional neuronal cells. These adipose-derived NSCs display a similar phenotype to those directly derived from embryonic brain. When differentiated into neurons, cells derived from adipose tissue have spontaneous spiking activity with network characteristics similar to that of neuronal cultures.

Acerola (Malpighia emarginata DC.) juice intake protects against alterations to proteins involved in inflammatory and lipolysis pathways in the adipose tissue of obese mice fed a cafeteria diet.

PubMed

Dias, Fernando Milanez; Leffa, Daniela Dimer; Daumann, Francine; Marques, Schérolin de Oliveira; Luciano, Thais F; Possato, Jonathan Correa; de Santana, Aline Alves; Neves, Rodrigo Xavier; Rosa, José Cesar; Oyama, Lila Missae; Rodrigues, Bruno; de Andrade, Vanessa Moraes; de Souza, Cláudio Teodoro; de Lira, Fabio Santos

2014-02-04

Obesity has been studied as a metabolic and an inflammatory disease and is characterized by increases in the production of pro-inflammatory adipokines in the adipose tissue.To elucidate the effects of natural dietary components on the inflammatory and metabolic consequences of obesity, we examined the effects of unripe, ripe and industrial acerola juice (Malpighia emarginata DC.) on the relevant inflammatory and lipolysis proteins in the adipose tissue of mice with cafeteria diet-induced obesity. Two groups of male Swiss mice were fed on a standard diet (STA) or a cafeteria diet (CAF) for 13 weeks. Afterwards, the CAF-fed animals were divided into five subgroups, each of which received a different supplement for one further month (water, unripe acerola juice, ripe acerola juice, industrial acerola juice, or vitamin C) by gavage. Enzyme-linked immunosorbent assays, Western blotting, a colorimetric method and histology were utilized to assess the observed data. The CAF water (control obese) group showed a significant increase in their adiposity indices and triacylglycerol levels, in addition to a reduced IL-10/TNF-α ratio in the adipose tissue, compared with the control lean group. In contrast, acerola juice and Vitamin C intake ameliorated the weight gain, reducing the TAG levels and increasing the IL-10/TNF-α ratio in adipose tissue. In addition, acerola juice intake led to reductions both in the level of phosphorylated JNK and to increases in the phosphorylation of IκBα and HSLser660 in adipose tissue. Taken together, these results suggest that acerola juice reduces low-grade inflammation and ameliorates obesity-associated defects in the lipolytic processes.

Hydrogel derived from decellularized porcine adipose tissue as a promising biomaterial for soft tissue augmentation.

PubMed

Tan, Qiu-Wen; Zhang, Yi; Luo, Jing-Cong; Zhang, Di; Xiong, Bin-Jun; Yang, Ji-Qiao; Xie, Hui-Qi; Lv, Qing

2017-06-01

Decellularized extracellular matrix (ECM) scaffolds from human adipose tissue, characterized by impressive adipogenic induction ability, are promising for soft tissue augmentation. However, scaffolds from autologous human adipose tissue are limited by the availability of tissue resources and the time necessary for scaffold fabrication. The objective of the current study was to investigate the adipogenic properties of hydrogels of decellularized porcine adipose tissue (HDPA). HDPA induced the adipogenic differentiation of human adipose-derived stem cells (ADSCs) in vitro, with significantly increased expression of adipogenic genes. Subcutaneous injection of HDPA in immunocompetent mice induced host-derived adipogenesis without cell seeding, and adipogenesis was significantly enhanced with ADSCs seeding. The newly formed adipocytes were frequently located on the basal side in the non-seeding group, but this trend was not observed in the ADSCs seeding group. Our results indicated that, similar to human adipose tissue, the ECM scaffold derived from porcine adipose tissue could provide an adipogenic microenvironment for adipose tissue regeneration and is a promising biomaterial for soft tissue augmentation. © 2017 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 105A: 1756-1764, 2017. © 2017 Wiley Periodicals, Inc.

Opposite Effects of Soluble Factors Secreted by Adipose Tissue on Proliferating and Quiescent Osteosarcoma Cells.

PubMed

Avril, Pierre; Duteille, Franck; Ridel, Perrine; Heymann, Marie-Françoise; De Pinieux, Gonzague; Rédini, Françoise; Blanchard, Frédéric; Heymann, Dominique; Trichet, Valérie; Perrot, Pierre

2016-03-01

Autologous adipose tissue transfer may be performed for aesthetic needs following resection of osteosarcoma, the most frequent primary malignant tumor of bone, excluding myeloma. The safety of autologous adipose tissue transfer regarding the potential risk of cancer recurrence must be addressed. Adipose tissue injection was tested in a human osteosarcoma preclinical model induced by MNNG-HOS cells. Culture media without growth factors from fetal bovine serum were conditioned with adipose tissue samples and added to two osteosarcoma cell lines (MNNG-HOS and MG-63) that were cultured in monolayer or maintained in nonadherent spheres, favoring a proliferation or quiescent stage, respectively. Proliferation and cell cycle were analyzed. Adipose tissue injection increased local growth of osteosarcoma in mice but was not associated with aggravation of lung metastasis or osteolysis. Adipose tissue-derived soluble factors increased the in vitro proliferation of osteosarcoma cells up to 180 percent. Interleukin-6 and leptin were measured in higher concentrations in adipose tissue-conditioned medium than in osteosarcoma cell-conditioned medium, but the authors' results indicated that they were not implicated alone. Furthermore, adipose tissue-derived soluble factors did not favor a G0-to-G1 phase transition of MNNG-HOS cells in nonadherent oncospheres. This study indicates that adipose tissue-soluble factors activate osteosarcoma cell cycle from G1 to mitosis phases, but do not promote the transition from quiescent G0 to G1 phases. Autologous adipose tissue transfer may not be involved in the activation of dormant tumor cells or cancer stem cells.

Flow cytometry on the stromal-vascular fraction of white adipose tissue

USDA-ARS?s Scientific Manuscript database

Adipose tissue contains cell types other than adipocytes that may contribute to complications linked to obesity. For example, macrophages have been shown to infiltrate adipose tissue in response to a high-fat diet. Isolation of the stromal-vascular fraction of adipose tissue allows one to use flow c...

Dietary cholesterol worsens adipose tissue macrophage accumulation and atherosclerosis in obese LDL receptor-deficient mice

PubMed Central

Subramanian, Savitha; Han, Chang Yeop; Chiba, Tsuyoshi; McMillen, Timothy S.; Wang, Shari A.; Haw, Antonio; Kirk, Elizabeth A.; O’Brien, Kevin D.; Chait, Alan

2009-01-01

Objective Chronic systemic inflammation accompanies obesity and predicts development of cardiovascular disease. Dietary cholesterol has been shown to increase inflammation and atherosclerosis in LDL receptor-deficient (LDLR-/-) mice. This study was undertaken to determine whether dietary cholesterol and obesity have additive effects on inflammation and atherosclerosis. Methods and Results LDLR-/- mice were fed chow, high fat, high carbohydrate (diabetogenic) diet without (DD) or with added cholesterol (DDC) for 24 weeks. Effects on adipose tissue, inflammatory markers and atherosclerosis were studied. Despite similar weight gain between DD and DDC groups, addition of dietary cholesterol increased insulin resistance relative to DD. Adipocyte hypertrophy, macrophage accumulation and local inflammation were observed in intra-abdominal adipose tissue in DD and DDC, but were significantly higher in the DDC group. Circulating levels of the inflammatory protein serum amyloid A (SAA) were 4.4-fold higher in DD animals and 15-fold higher in DDC animals than controls, suggesting chronic systemic inflammation. Hepatic SAA mRNA levels were similarly elevated. Atherosclerosis was increased in the DD-fed animals and further increased in the DDC group. Conclusions Obesity-induced macrophage accumulation in adipose tissue is exacerbated by dietary cholesterol. These local inflammatory changes in adipose tissue are associated with insulin resistance, systemic inflammation and increased atherosclerosis in this mouse model. PMID:18239153

Differential effect of subcutaneous abdominal and visceral adipose tissue on cardiometabolic risk.

PubMed

Sam, Susan

2018-03-09

Metabolic and cardiovascular diseases are increasing worldwide due to the rise in the obesity epidemic. The metabolic consequences of obesity vary by distribution of adipose tissue. Visceral and ectopic adipose accumulation are associated with adverse cardiometabolic consequences, while gluteal-femoral adipose accumulation are negatively associated with these adverse complications and subcutaneous abdominal adipose accumulation is more neutral in its associations. Gender, race and ethnic differences in adipose tissue distribution have been described and could account for the observed differences in risk for cardiometabolic disease. The mechanisms behind the differential impact of adipose tissue on cardiometabolic risk have started to be unraveled and include differences in adipocyte biology, inflammatory profile, connection to systemic circulation and most importantly the inability of the subcutaneous adipose tissue to expand in response to positive energy balance.

Insulin response in individual tissues of control and gold thioglucose-obese mice in vivo with (1-/sup 14/C)2-deoxyglucose

DOE Office of Scientific and Technical Information (OSTI.GOV)

Cooney, G.J.; Astbury, L.D.; Williams, P.F.

The dose-response characteristics of several glucose-utilizing tissues (brain, heart, white adipose tissue, brown adipose tissue, and quadriceps muscle) to a single injection of insulin have been compared in control mice and mice made obese with a single injection of gold thioglucose (GTG). Tissue content of (1-/sup 14/C)2-deoxyglucose 6-phosphate and blood disappearance rate of (1-/sup 14/C)2-deoxyglucose (2-DG) were measured at nine different insulin doses and used to calculate rates of 2-DG uptake and phosphorylation in tissues from control and obese mice. The insulin sensitivity of tissues reflected in the ED50 of insulin response varied widely, and brown adipose tissue was themore » most insulin-sensitive tissue studied. In GTG-obese mice, heart, quadriceps, and brown adipose tissue were insulin resistant (demonstrated by increased ED50), whereas in white adipose tissue, 2-DG phosphorylation was more sensitive to insulin. Brain 2-DG phosphorylation was insulin independent in control and obese animals. The largest decrease in insulin sensitivity in GTG-obese mice was observed in brown adipose tissue. The loss of diet-induced thermogenesis in brown adipose tissue as a result of the hypothalamic lesion in GTG-obese mice could be a major cause of insulin resistance in brown adipose tissue. Because brown adipose tissue can make a major contribution to whole-body glucose utilization, insulin resistance in this tissue may have a significant effect on whole-animal glucose homeostasis in GTG-obese mice.« less

Digital histologic analysis reveals morphometric patterns of age-related involution in breast epithelium and stroma.

PubMed

Sandhu, Rupninder; Chollet-Hinton, Lynn; Kirk, Erin L; Midkiff, Bentley; Troester, Melissa A

2016-02-01

Complete age-related regression of mammary epithelium, often termed postmenopausal involution, is associated with decreased breast cancer risk. However, most studies have qualitatively assessed involution. We quantitatively analyzed epithelium, stroma, and adipose tissue from histologically normal breast tissue of 454 patients in the Normal Breast Study. High-resolution digital images of normal breast hematoxylin and eosin-stained slides were partitioned into epithelium, adipose tissue, and nonfatty stroma. Percentage area and nuclei per unit area (nuclear density) were calculated for each component. Quantitative data were evaluated in association with age using linear regression and cubic spline models. Stromal area decreased (P = 0.0002), and adipose tissue area increased (P < 0.0001), with an approximate 0.7% change in area for each component, until age 55 years when these area measures reached a steady state. Although epithelial area did not show linear changes with age, epithelial nuclear density decreased linearly beginning in the third decade of life. No significant age-related trends were observed for stromal or adipose nuclear density. Digital image analysis offers a high-throughput method for quantitatively measuring tissue morphometry and for objectively assessing age-related changes in adipose tissue, stroma, and epithelium. Epithelial nuclear density is a quantitative measure of age-related breast involution that begins to decline in the early premenopausal period. Copyright © 2015 Elsevier Inc. All rights reserved.

Effects of endurance exercise training, metformin, and their combination on adipose tissue leptin and IL-10 secretion in OLETF rats

PubMed Central

Padilla, Jaume; Arce-Esquivel, Arturo A.; Bayless, David S.; Martin, Jeffrey S.; Leidy, Heather J.; Booth, Frank W.; Rector, R. Scott; Laughlin, M. Harold

2012-01-01

Adipose tissue inflammation plays a role in cardiovascular (CV) and metabolic diseases associated with obesity, insulin resistance, and type 2 diabetes mellitus (T2DM). The interactive effects of exercise training and metformin, two first-line T2DM treatments, on adipose tissue inflammation are not known. Using the hyperphagic, obese, insulin-resistant Otsuka Long-Evans Tokushima Fatty (OLETF) rat model, we tested the hypothesis that treadmill training, metformin, or a combination of these reduces the secretion of proinflammatory cytokines from adipose tissue. Compared with Long-Evans Tokushima Otsuka (LETO) control rats (L-Sed), sedentary OLETF (O-Sed) animals secreted significantly greater amounts of leptin from retroperitoneal adipose tissue. Conversely, secretion of interleukin (IL)-10 by O-Sed adipose tissue was lower than that in L-Sed animals. Examination of leptin and IL-10 secretion from adipose tissue in OLETF groups treated with endurance exercise training (O-EndEx), metformin treatment (O-Met), and a combination of these (O-E+M) from 20 to 32 wk of age indicated that 1) leptin secretion from adipose tissue was reduced in O-Met and O-E+M, but not O-EndEx animals; 2) adipose tissue IL-10 secretion was increased in O-EndEx and O-E+M but not in O-Met animals; and 3) only the combined treatment (O-E+M) displayed both a reduction in leptin secretion and an increase in IL-10 secretion. Leptin and IL-10 concentrations in adipose tissue–conditioned buffers were correlated with their plasma concentrations, adipocyte diameters, and total adiposity. Overall, this study indicates that exercise training and metformin have additive influences on adipose tissue secretion and plasma concentrations of leptin and IL-10. PMID:23019312

The role of adipose tissue in cancer-associated cachexia.

PubMed

Vaitkus, Janina A; Celi, Francesco S

2017-03-01

Adipose tissue (fat) is a heterogeneous organ, both in function and histology, distributed throughout the body. White adipose tissue, responsible for energy storage and more recently found to have endocrine and inflammation-modulatory activities, was historically thought to be the only type of fat present in adult humans. The recent demonstration of functional brown adipose tissue in adults, which is highly metabolic, shifted this paradigm. Additionally, recent studies demonstrate the ability of white adipose tissue to be induced toward the brown adipose phenotype - "beige" or "brite" adipose tissue - in a process referred to as "browning." While these adipose tissue depots are under investigation in the context of obesity, new evidence suggests a maladaptive role in other metabolic disturbances including cancer-associated cachexia, which is the topic of this review. This syndrome is multifactorial in nature and is an independent factor associated with poor prognosis. Here, we review the contributions of all three adipose depots - white, brown, and beige - to the development and progression of cancer-associated cachexia. Specifically, we focus on the local and systemic processes involving these adipose tissues that lead to increased energy expenditure and sustained negative energy balance. We highlight key findings from both animal and human studies and discuss areas within the field that need further exploration. Impact statement Cancer-associated cachexia (CAC) is a complex, multifactorial syndrome that negatively impacts patient quality of live and prognosis. This work reviews a component of CAC that lacks prior discussion: adipose tissue contributions. Uniquely, it discusses all three types of adipose tissue, white, beige, and brown, their interactions, and their contributions to the development and progression of CAC. Summarizing key bench and clinical studies, it provides information that will be useful to both basic and clinical researchers in designing experiments, studies, and clinical trials.

Regulatory iNKT cells lack PLZF expression and control Treg cell and macrophage homeostasis in adipose tissue

PubMed Central

Lynch, Lydia; Michelet, Xavier; Zhang, Sai; Brennan, Patrick J.; Moseman, Ashley; Lester, Chantel; Besra, Gurdyal; Vomhof-Dekrey, Emilie E.; Tighe, Mike; Koay, Hui-Fern; Godfrey, Dale I.; Leadbetter, Elizabeth A.; Sant’Angelo, Derek B.; von Andrian, Ulrich; Brenner, Michael B.

2015-01-01

iNKT cells are CD1d-restricted lipid-sensing innate T cells that express the transcription factor PLZF. iNKT cells accumulate in adipose tissue, where they are anti-inflammatory, but the factors that contribute to their anti-inflammatory nature, and their targets in adipose tissue are unknown. Here we report that adipose tissue iNKT cells have a unique transcriptional program and produce interleukin 2 (IL-2) and IL-10. Unlike other iNKT cells, they lack PLZF, but express the transcription factor E4BP4, which controls their IL-10 production. Adipose iNKT cells are a tissue resident population that induces an anti-inflammatory phenotype in macrophages and, through production of IL-2, controls the number, proliferation and suppressor function of adipose regulatory T (Treg) cells. Thus, adipose tissue iNKT cells are unique regulators of immune homeostasis in this tissue. PMID:25436972

Invited review: Pre- and postnatal adipose tissue development in farm animals: from stem cells to adipocyte physiology.

PubMed

Louveau, I; Perruchot, M-H; Bonnet, M; Gondret, F

2016-11-01

Both white and brown adipose tissues are recognized to be differently involved in energy metabolism and are also able to secrete a variety of factors called adipokines that are involved in a wide range of physiological and metabolic functions. Brown adipose tissue is predominant around birth, except in pigs. Irrespective of species, white adipose tissue has a large capacity to expand postnatally and is able to adapt to a variety of factors. The aim of this review is to update the cellular and molecular mechanisms associated with pre- and postnatal adipose tissue development with a special focus on pigs and ruminants. In contrast to other tissues, the embryonic origin of adipose cells remains the subject of debate. Adipose cells arise from the recruitment of specific multipotent stem cells/progenitors named adipose tissue-derived stromal cells. Recent studies have highlighted the existence of a variety of those cells being able to differentiate into white, brown or brown-like/beige adipocytes. After commitment to the adipocyte lineage, progenitors undergo large changes in the expression of many genes involved in cell cycle arrest, lipid accumulation and secretory functions. Early nutrition can affect these processes during fetal and perinatal periods and can also influence or pre-determinate later growth of adipose tissue. How these changes may be related to adipose tissue functional maturity around birth and can influence newborn survival is discussed. Altogether, a better knowledge of fetal and postnatal adipose tissue development is important for various aspects of animal production, including neonatal survival, postnatal growth efficiency and health.

Proinsulin-producing, hyperglycemia-induced adipose tissue macrophages underlie insulin resistance in high fat-fed diabetic mice

USDA-ARS?s Scientific Manuscript database

Adipose tissue macrophages play an important role in the pathogenesis of obese type 2 diabetes. High-fat diet-induced obesity has been shown to lead to adipose tissue macrophages accumulation in rodents;however, the impact of hyperglycemia on adipose tissue macrophages dynamics in high-fat diet-fed ...

Design of 3-D adipospheres for quantitative metabolic study

PubMed Central

Akama, Takeshi; Leung, Brendan M.; Labuz, Joseph M.; Takayama, Shuichi; Chun, Tae-Hwa

2017-01-01

Quantitative assessment of adipose mitochondrial activity is critical for better understanding of adipose tissue function in obesity and diabetes. While the two-dimensional (2-D) tissue culture method has been sufficient to discover key molecules that regulate adipocyte differentiation and function, the method is insufficient to determine the role of extracellular matrix (ECM) molecules and their modifiers, such as matrix metalloproteinases (MMPs), in regulating adipocyte function in three-dimensional (3-D) in vivo-like microenvironments. By using a 3-D hanging drop tissue culture system, we are able to produce scalable 3-D adipospheres that are suitable for quantitative mitochondrial study in 3-D microenvironment. PMID:28244051

White adipose tissue cells and the progression of cachexia: inflammatory pathways

PubMed Central

Neves, Rodrigo X.; Rosa‐Neto, José Cesar; Yamashita, Alex S.; Matos‐Neto, Emidio M.; Riccardi, Daniela M. R.; Lira, Fabio S.; Batista, Miguel L.

2015-01-01

Abstract Background Cachexia is a systemic syndrome leading to body wasting, systemic inflammation, and to metabolic chaos. It is a progressive condition, and little is known about its dynamics. Detection of the early signs of the disease may lead to the attenuation of the associated symptoms. The white adipose tissue is an organ with endocrine functions, capable of synthesising and secreting a plethora of proteins, including cytokines, chemokines, and adipokines. It is well established that different adipose tissue depots demonstrate heterogeneous responses to physiological and pathological stimuli. The present study aimed at providing insight into adipocyte involvement in inflammation along the progression of cachexia. Methods Eight‐weeks‐old male rats were subcutaneously inoculated with a Walker 256 carcinosarcoma cell suspension (2 × 107 cells in 1.0 mL; tumour‐bearing, T) or Phosphate‐buffered saline (control, C). The retroperitoneal, epididymal, and mesenteric adipose pads were excised on Days 0, 7, and 14 post‐tumour cell injection, and the adipocytes were isolated. Results Mesenteric and epididymal adipocytes showed up‐regulation of IL‐1β protein expression and activation of the inflammasome pathway, contributing for whole tissue inflammation. The stromal vascular fraction of the retroperitoneal adipose tissue, on the other hand, seems to be the major contributor for the inflammation in this specific pad. Conclusion Adipocytes seem to play a relevant role in the establishment of white adipose tissue inflammation, through the activation of the NF‐κB and inflammasome pathways. In epididymal adipocytes, induction of the inflammasome may be detected already on Day 7 post‐tumour cell inoculation. PMID:27493872

Acute Hypercortisolemia Exerts Depot-Specific Effects on Abdominal and Femoral Adipose Tissue Function

PubMed Central

O’Reilly, Michael W.; Bujalska, Iwona J.; Tomlinson, Jeremy W.; Arlt, Wiebke

2017-01-01

Context: Glucocorticoids have pleiotropic metabolic functions, and acute glucocorticoid excess affects fatty acid metabolism, increasing systemic lipolysis. Whether glucocorticoids exert adipose tissue depot-specific effects remains unclear. Objective: To provide an in vivo assessment of femoral and abdominal adipose tissue responses to acute glucocorticoid administration. Design and Outcome Measures: Nine healthy male volunteers were studied on two occasions, after a hydrocortisone infusion (0.2 mg/kg/min for 14 hours) and a saline infusion, respectively, given in randomized double-blind order. The subjects were studied in the fasting state and after a 75-g glucose drink with an in vivo assessment of femoral adipose tissue blood flow (ATBF) using radioactive xenon washout and of lipolysis and glucose uptake using the arteriovenous difference technique. In a separate study (same infusion design), eight additional healthy male subjects underwent assessment of fasting abdominal ATBF and lipolysis only. Lipolysis was assessed as the net release of nonesterified fatty acids (NEFAs) from femoral and abdominal subcutaneous adipose tissue. Results: Acute hypercortisolemia significantly increased basal and postprandial ATBF in femoral adipose tissue, but the femoral net NEFA release did not change. In abdominal adipose tissue, hypercortisolemia induced substantial increases in basal ATBF and NEFA release. Conclusions: Acute hypercortisolemia induces differential lipolysis and ATBF responses in abdominal and femoral adipose tissue, suggesting depot-specific glucocorticoid effects. Abdominal, but not femoral, adipose tissue contributes to the hypercortisolemia-induced systemic NEFA increase, with likely contributions from other adipose tissue sources and intravascular triglyceride hydrolysis. PMID:28323916

Stevioside ameliorates high-fat diet-induced insulin resistance and adipose tissue inflammation by downregulating the NF-{kappa}B pathway

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wang, Zhiquan; Xue, Liqiong; Guo, Cuicui

Highlights: Black-Right-Pointing-Pointer Stevioside ameliorates high-fat diet-induced insulin resistance. Black-Right-Pointing-Pointer Stevioside alleviates the adipose tissue inflammation. Black-Right-Pointing-Pointer Stevioside reduces macrophages infiltration into the adipose tissue. Black-Right-Pointing-Pointer Stevioside suppresses the activation of NF-{kappa}B in the adipose tissue. -- Abstract: Accumulating evidence suggests that adipose tissue is the main source of pro-inflammatory molecules that predispose individuals to insulin resistance. Stevioside (SVS) is a widely used sweetener with multiple beneficial effects for diabetic patients. In this study, we investigated the effect of SVS on insulin resistance and the pro-inflammatory state of adipose tissue in mice fed with a high-fat diet (HFD). Oral administration ofmore » SVS for 1 month had no effect on body weight, but it significantly improved fasting glucose, basal insulin levels, glucose tolerance and whole body insulin sensitivity. Interestingly, these changes were accompanied with decreased expression levels of several inflammatory cytokines in adipose tissue, including TNF-{alpha}, IL6, IL10, IL1{beta}, KC, MIP-1{alpha}, CD11b and CD14. Moreover, macrophage infiltration in adipose tissue was remarkably reduced by SVS. Finally, SVS significantly suppressed the nuclear factor-kappa b (NF-{kappa}B) signaling pathway in adipose tissue. Collectively, these results suggested that SVS may ameliorate insulin resistance in HFD-fed mice by attenuating adipose tissue inflammation and inhibiting the NF-{kappa}B pathway.« less

Supercritical carbon dioxide extracted extracellular matrix material from adipose tissue.

PubMed

Wang, Jun Kit; Luo, Baiwen; Guneta, Vipra; Li, Liang; Foo, Selin Ee Min; Dai, Yun; Tan, Timothy Thatt Yang; Tan, Nguan Soon; Choong, Cleo; Wong, Marcus Thien Chong

2017-06-01

Adipose tissue is a rich source of extracellular matrix (ECM) material that can be isolated by delipidating and decellularizing the tissue. However, the current delipidation and decellularization methods either involve tedious and lengthy processes or require toxic chemicals, which may result in the elimination of vital proteins and growth factors found in the ECM. Hence, an alternative delipidation and decellularization method for adipose tissue was developed using supercritical carbon dioxide (SC-CO 2 ) that eliminates the need of any harsh chemicals and also reduces the amount of processing time required. The resultant SC-CO 2 -treated ECM material showed an absence of nuclear content but the preservation of key proteins such as collagen Type I, collagen Type III, collagen Type IV, elastin, fibronectin and laminin. In addition, other biological factors such as glycosaminoglycans (GAGs) and growth factors such as basic fibroblast growth factor (bFGF) and vascular endothelial growth factor (VEGF) were also retained. Subsequently, the resulting SC-CO 2 -treated ECM material was used as a bioactive coating on tissue culture plastic (TCP). Four different cell types including adipose tissue-derived mesenchymal stem cells (ASCs), human umbilical vein endothelial cells (HUVECs), immortalized human keratinocyte (HaCaT) cells and human monocytic leukemia cells (THP-1) were used in this study to show that the SC-CO 2 -treated ECM coating can be potentially used for various biomedical applications. The SC-CO 2 -treated ECM material showed improved cell-material interactions for all cell types tested. In addition, in vitro scratch wound assay using HaCaT cells showed that the presence of SC-CO 2 -treated ECM material enhanced keratinocyte migration whilst the in vitro cellular studies using THP-1-derived macrophages showed that the SC-CO 2 -treated ECM material did not evoke pro-inflammatory responses from the THP-1-derived macrophages. Overall, this study shows the efficacy of SC-CO 2 method for delipidation and decellularization of adipose tissue whilst retaining its ECM and its subsequent utilization as a bioactive surface coating material for soft tissue engineering, angiogenesis and wound healing applications. Copyright © 2017 Elsevier B.V. All rights reserved.

The tumour suppressor CDKN2A/p16INK4a regulates adipogenesis and bone marrow-dependent development of perivascular adipose tissue

PubMed Central

Wouters, Kristiaan; Deleye, Yann; Hannou, Sarah A; Vanhoutte, Jonathan; Maréchal, Xavier; Coisne, Augustin; Tagzirt, Madjid; Derudas, Bruno; Bouchaert, Emmanuel; Duhem, Christian; Vallez, Emmanuelle; Schalkwijk, Casper G; Pattou, François; Montaigne, David; Staels, Bart; Paumelle, Réjane

2017-01-01

The genomic CDKN2A/B locus, encoding p16INK4a among others, is linked to an increased risk for cardiovascular disease and type 2 diabetes. Obesity is a risk factor for both cardiovascular disease and type 2 diabetes. p16INK4a is a cell cycle regulator and tumour suppressor. Whether it plays a role in adipose tissue formation is unknown. p16INK4a knock-down in 3T3/L1 preadipocytes or p16INK4a deficiency in mouse embryonic fibroblasts enhanced adipogenesis, suggesting a role for p16INK4a in adipose tissue formation. p16INK4a-deficient mice developed more epicardial adipose tissue in response to the adipogenic peroxisome proliferator activated receptor gamma agonist rosiglitazone. Additionally, adipose tissue around the aorta from p16INK4a-deficient mice displayed enhanced rosiglitazone-induced gene expression of adipogenic markers and stem cell antigen, a marker of bone marrow-derived precursor cells. Mice transplanted with p16INK4a-deficient bone marrow had more epicardial adipose tissue compared to controls when fed a high-fat diet. In humans, p16INK4a gene expression was enriched in epicardial adipose tissue compared to other adipose tissue depots. Moreover, epicardial adipose tissue from obese humans displayed increased expression of stem cell antigen compared to lean controls, supporting a bone marrow origin of epicardial adipose tissue. These results show that p16INK4a modulates epicardial adipose tissue development, providing a potential mechanistic link between the genetic association of the CDKN2A/B locus and cardiovascular disease risk. PMID:28868898

Role of adipose tissue-derived stem cells in the progression of renal disease.

PubMed

Donizetti-Oliveira, Cassiano; Semedo, Patricia; Burgos-Silva, Marina; Cenedeze, Marco Antonio; Malheiros, Denise Maria Avancini Costa; Reis, Marlene Antônia Dos; Pacheco-Silva, Alvaro; Câmara, Niels Olsen Saraiva

2011-03-01

To analyze the role of adipose tissue-derived stem cells in reducing the progression of renal fibrosis. adipose tissue-derived stem cells were isolated from C57Bl/6 mice and characterized by cytometry and differentiation. Renal fibrosis was established after unilateral clamping of the renal pedicle for 1 hour. Four hours after reperfusion, 2.105 adipose tissue-derived stem cells were administered intraperitoneally and the animals were followed for 24 hours during 6 weeks. In another experimental group, 2.105adipose tissue-derived stem cells were administered only after 6 weeks of reperfusion, and they were euthanized and studied 4 weeks later. Twenty-four hours after reperfusion, the animals treated with adipose tissue-derived stem cells displayed reduced renal and tubular dysfunction and an increase of the regenerative process. Renal expression of IL-6 and TNF mRNA were decreased in the animals treated with adipose tissue-derived stem cells, while the levels of IL-4, IL-10, and HO-1 were increased, despite the fact that adipose tissue-derived stem cells were not observed in the kidneys via SRY analysis. In 6 weeks, the kidneys of non-treated animals decreased in size, and the kidneys of the animals treated with adipose tissue-derived stem cells remained at normal size and display less deposition of type 1 collagen and FSP-1. The renal protection observed in animals treated with adipose tissue-derived stem cells was followed by a drop in serum levels of TNF-α, KC, RANTES, and IL-1a. Treatment with adipose tissue-derived stem cells after 6 weeks, when the animals already displayed established fibrosis, demonstrated an improvement in functional parameters and less fibrosis analyzed by Picrosirius stain, as well as a reduction of the expression of type 1 collagen and vimentin mRNA. Treatment with adipose tissue-derived stem cells may deter the progression of renal fibrosis by modulation of the early inflammatory response, likely via reduction of the epithelial-mesenchymal transition.

Adipose Tissue Is a Neglected Viral Reservoir and an Inflammatory Site during Chronic HIV and SIV Infection

PubMed Central

Damouche, Abderaouf; Huot, Nicolas; Dejucq-Rainsford, Nathalie; Satie, Anne-Pascale; Mélard, Adeline; David, Ludivine; Gommet, Céline; Ghosn, Jade; Noel, Nicolas; Pourcher, Guillaume; Martinez, Valérie; Benoist, Stéphane; Béréziat, Véronique; Cosma, Antonio; Favier, Benoit; Vaslin, Bruno; Rouzioux, Christine; Capeau, Jacqueline; Müller-Trutwin, Michaela; Dereuddre-Bosquet, Nathalie; Le Grand, Roger; Lambotte, Olivier; Bourgeois, Christine

2015-01-01

Two of the crucial aspects of human immunodeficiency virus (HIV) infection are (i) viral persistence in reservoirs (precluding viral eradication) and (ii) chronic inflammation (directly associated with all-cause morbidities in antiretroviral therapy (ART)-controlled HIV-infected patients). The objective of the present study was to assess the potential involvement of adipose tissue in these two aspects. Adipose tissue is composed of adipocytes and the stromal vascular fraction (SVF); the latter comprises immune cells such as CD4+ T cells and macrophages (both of which are important target cells for HIV). The inflammatory potential of adipose tissue has been extensively described in the context of obesity. During HIV infection, the inflammatory profile of adipose tissue has been revealed by the occurrence of lipodystrophies (primarily related to ART). Data on the impact of HIV on the SVF (especially in individuals not receiving ART) are scarce. We first analyzed the impact of simian immunodeficiency virus (SIV) infection on abdominal subcutaneous and visceral adipose tissues in SIVmac251 infected macaques and found that both adipocytes and adipose tissue immune cells were affected. The adipocyte density was elevated, and adipose tissue immune cells presented enhanced immune activation and/or inflammatory profiles. We detected cell-associated SIV DNA and RNA in the SVF and in sorted CD4+ T cells and macrophages from adipose tissue. We demonstrated that SVF cells (including CD4+ T cells) are infected in ART-controlled HIV-infected patients. Importantly, the production of HIV RNA was detected by in situ hybridization, and after the in vitro reactivation of sorted CD4+ T cells from adipose tissue. We thus identified adipose tissue as a crucial cofactor in both viral persistence and chronic immune activation/inflammation during HIV infection. These observations open up new therapeutic strategies for limiting the size of the viral reservoir and decreasing low-grade chronic inflammation via the modulation of adipose tissue-related pathways. PMID:26402858

A post-reconstruction method to correct cupping artifacts in cone beam breast computed tomography

PubMed Central

Altunbas, M. C.; Shaw, C. C.; Chen, L.; Lai, C.; Liu, X.; Han, T.; Wang, T.

2007-01-01

In cone beam breast computed tomography (CT), scattered radiation leads to nonuniform biasing of CT numbers known as a cupping artifact. Besides being visual distractions, cupping artifacts appear as background nonuniformities, which impair efficient gray scale windowing and pose a problem in threshold based volume visualization/segmentation. To overcome this problem, we have developed a background nonuniformity correction method specifically designed for cone beam breast CT. With this technique, the cupping artifact is modeled as an additive background signal profile in the reconstructed breast images. Due to the largely circularly symmetric shape of a typical breast, the additive background signal profile was also assumed to be circularly symmetric. The radial variation of the background signals were estimated by measuring the spatial variation of adipose tissue signals in front view breast images. To extract adipose tissue signals in an automated manner, a signal sampling scheme in polar coordinates and a background trend fitting algorithm were implemented. The background fits compared with targeted adipose tissue signal value (constant throughout the breast volume) to get an additive correction value for each tissue voxel. To test the accuracy, we applied the technique to cone beam CT images of mastectomy specimens. After correction, the images demonstrated significantly improved signal uniformity in both front and side view slices. The reduction of both intra-slice and inter-slice variations in adipose tissue CT numbers supported our observations. PMID:17822018

Dietary olive oil induces cannabinoid CB2 receptor expression in adipose tissue of ApcMin/+ transgenic mice

PubMed Central

Notarnicola, Maria; Tutino, Valeria; Tafaro, Angela; Bianco, Giusy; Guglielmi, Emilia; Caruso, Maria Gabriella

2016-01-01

BACKGROUND: Cannabinoid- 2 (CB2) receptor is known for its anti-obesity effects silencing the activated immune cells that are key drivers of metabolic syndrome and inflammation. Nutritional interventions in experimental models of carcinogenesis have been demonstrated to modulate tissue inflammation state and proliferation. OBJECTIVE: Aim of this study was to test, in ApcMin/+ mice, whether a diet enriched with olive oil, omega- 3 and omega-6- PUFAs affects the adipose tissue inflammation status. METHODS: Four groups of animal were studied: ST group, receiving a standard diet; OO group, receiving the standard diet in which soybean oil (source of fats) was replaced with olive oil; OM-3 group, receiving the standard diet in which soybean oil was replaced with salmon oil; OM-6 group, receiving the standard diet in which soybean oil was replaced with oenothera oil. Gene and protein expression, in adipose tissue, were evaluated by RT-PCR and Western Blotting, respectively. Enzymatic activities were assayed by fluorescent and radiometric method, where appropriated. RESULTS: The diet enriched with olive oil significantly induced CB2 receptor expression and it was able to control inflammatory and proliferative activity of mice adipose tissue. CONCLUSIONS: The present findings open opportunities for developing novel nutritional strategies considering olive oil a key ingredient of a healthy dietary pattern. PMID:28035344

Adipose tissue engineering: state of the art, recent advances and innovative approaches.

PubMed

Tanzi, Maria Cristina; Farè, Silvia

2009-09-01

Adipose tissue is a highly specialized connective tissue found either in white or brown forms, the white form being the most abundant in adult humans. Loss or damage of white adipose tissue due to aging or pathological conditions needs reconstructive approaches. To date, two main strategies are being investigated for generating functional adipose tissue: autologous tissue/cell transplantation and adipose tissue engineering. Free-fat transplantation rarely achieves sufficient tissue augmentation owing to delayed neovascularization, with subsequent cell necrosis and graft volume shrinkage. Tissue engineering approaches represent, instead, a more suitable alternative for adipose tissue regeneration; they can be performed either with in situ or de novo adipogenesis. In situ adipogenesis or transplantation of encapsulated cells can be useful in healing small-volume defects, whereas restoration of large defects, where vascularization and a rapid volumetric gain are strict requirements, needs de novo strategies with 3D scaffold/filling matrix combinations. For adipose tissue engineering, the use of adult mesenchymal stem cells (both adipose- and bone marrow-derived stem cells) or of preadipocytes is preferred to the use of mature adipocytes, which have low expandability and poor ability for volume retention. This review intends to assemble and describe recent work on this topic, critically presenting successes obtained and drawbacks faced to date.

Immune response in the adipose tissue of lean mice infected with the protozoan parasite Neospora caninum

PubMed Central

Teixeira, Luzia; Moreira, João; Melo, Joana; Bezerra, Filipa; Marques, Raquel M; Ferreirinha, Pedro; Correia, Alexandra; Monteiro, Mariana P; Ferreira, Paula G; Vilanova, Manuel

2015-01-01

The adipose tissue can make important contributions to immune function. Nevertheless, only a limited number of reports have investigated in lean hosts the immune response elicited in this tissue upon infection. Previous studies suggested that the intracellular protozoan Neospora caninum might affect adipose tissue physiology. Therefore, we investigated in mice challenged with this protozoan if immune cell populations within adipose tissue of different anatomical locations could be differently affected. Early in infection, parasites were detected in the adipose tissue and by 7 days of infection increased numbers of macrophages, regulatory T (Treg) cells and T-bet+ cells were observed in gonadal, mesenteric, omental and subcutaneous adipose tissue. Increased expression of interferon-γ was also detected in gonadal adipose tissue of infected mice. Two months after infection, parasite DNA was no longer detected in these tissues, but T helper type 1 (Th1) cell numbers remained above control levels in the infected mice. Moreover, the Th1/Treg cell ratio was higher than that of controls in the mesenteric and subcutaneous adipose tissue. Interestingly, chronically infected mice presented a marked increase of serum leptin, a molecule that plays a role in energy balance regulation as well as in promoting Th1-type immune responses. Altogether, we show that an apicomplexa parasitic infection influences immune cellular composition of adipose tissue throughout the body as well as adipokine production, still noticed at a chronic phase of infection when parasites were already cleared from that particular tissue. This strengthens the emerging view that infections can have long-term consequences for the physiology of adipose tissue. PMID:25581844

Fast isolation and expansion of multipotent cells from adipose tissue based on chitosan-selected primary culture.

PubMed

Huang, Guo-Shiang; Tseng, Ting-Chen; Dai, Niann-Tzyy; Fu, Keng-Yen; Dai, Lien-Guo; Hsu, Shan-Hui

2015-10-01

Adipose-derived adult stem cells (ASCs) have gained much attention because of their multipotency and easy access. Here we describe a novel chitosan-based selection (CS) system instead of the conventional plastic adherence (PA) to obtain the primary ASCs. The minimal amount of adipose tissue for consistent isolation of ASCs is reduced from 10 mL to 5 mL. The selection is based on the specific interaction between cells and chitosan materials, which separate ASCs by forming spheroids during primary culture. The primary culture period was reduced from 4 days to one day and more ASCs (ten-fold expansion) were achieved in a week. The average duration for obtaining 1 × 10(7) cells takes about seven days from 5 mL of adipose tissue, compared to 14 days using the conventional PA method from 10 mL of adipose tissue. The replicative senescence of CS-ASCs is not evident until the fifteenth passage (vs. eighth for the PA-ASCs). The obtained ASCs (CS-ASCs) have less doubling time for the same passage of cells and show greater stemness than those obtained from the conventional PA method (PA-ASCs). Moreover, CS-ASCs undergo trilineage differentiation more effectively than PA-ASCs. The greater differentiation potential of CS-ASCs may be associated with the enrichment and maintenance of CD271 positive cells by chitosan selection of primary culture. Copyright © 2015 Elsevier Ltd. All rights reserved.

Adipose tissue: cell heterogeneity and functional diversity.

PubMed

Esteve Ràfols, Montserrat

2014-02-01

There are two types of adipose tissue in the body whose function appears to be clearly differentiated. White adipose tissue stores energy reserves as fat, whereas the metabolic function of brown adipose tissue is lipid oxidation to produce heat. A good balance between them is important to maintain energy homeostasis. The concept of white adipose tissue has radically changed in the past decades, and is now considered as an endocrine organ that secretes many factors with autocrine, paracrine, and endocrine functions. In addition, we can no longer consider white adipose tissue as a single tissue, because it shows different metabolic profiles in its different locations, with also different implications. Although the characteristic cell of adipose tissue is the adipocyte, this is not the only cell type present in adipose tissue, neither the most abundant. Other cell types in adipose tissue described include stem cells, preadipocytes, macrophages, neutrophils, lymphocytes, and endothelial cells. The balance between these different cell types and their expression profile is closely related to maintenance of energy homeostasis. Increases in adipocyte size, number and type of lymphocytes, and infiltrated macrophages are closely related to the metabolic syndrome diseases. The study of regulation of proliferation and differentiation of preadipocytes and stem cells, and understanding of the interrelationship between the different cell types will provide new targets for action against these diseases. Copyright © 2012 SEEN. Published by Elsevier Espana. All rights reserved.

Adipose tissue in myocardial infarction.

PubMed

Su, Leon; Siegel, John E; Fishbein, Michael C

2004-01-01

The histologic evolution of myocardial infarction (MI) has been studied in some detail. However, there is little mention of the presence of adipose tissue in healed MI(HMI). Ninety-one hearts explanted during 1997-2001 were examined to determine the extent of adipose tissue within HMI. The medical records, surgical pathology reports, and all histologic sections of the explanted heart, from patients undergoing heart transplantation for ischemic heart disease, were reviewed. Adipose tissue within the areas of HMI was quantified. The location of the HMI, the age and gender of the patient, age of HMI, and whether the patient was treated with coronary artery bypass surgery (CABG) were noted. Of the 91 hearts examined, 168 HMIs were identified; 141 (84%) contained some mature fat within the HMI. Adipose tissue increased with increasing age, in males, and in those patients who had CABG surgery. The amount of adipose tissue was not related to the location or age of the HMI. Adipose tissue is a prevalent histological finding in HMIs. The pathogenesis of adipose tissue is unknown, but may be influenced by current medical therapy for ischemic heart disease, thus explaining why adipose tissue in HMIs was not reported until 1997. The presence of fat supports the speculation that a regenerative cell, or multipotent stem cell, exists within the heart, and under the influence of microenvironmental or therapeutic factors can differentiate into fat, other mesenchymal tissues, and potentially even myocardium.

Association between subcutaneous white adipose tissue and serum 25-hydroxyvitamin D in overweight and obese adults

USDA-ARS?s Scientific Manuscript database

Background: Cholecalciferol is known to be deposited in human adipose tissue, but the distribution of 25-hydroxyvitamin D (25(OH)D) in adipose tissue is not known. Objectives: To determine whether 25(OH)D is detectable in subcutaneous white adipose tissue (SWAT) in overweight and obese persons an...

Lysophosphatidic acid receptor mRNA levels in heart and white adipose tissue are associated with obesity in mice and humans.

PubMed

Brown, Amy; Hossain, Intekhab; Perez, Lester J; Nzirorera, Carine; Tozer, Kathleen; D'Souza, Kenneth; Trivedi, Purvi C; Aguiar, Christie; Yip, Alexandra M; Shea, Jennifer; Brunt, Keith R; Legare, Jean-Francois; Hassan, Ansar; Pulinilkunnil, Thomas; Kienesberger, Petra C

2017-01-01

Lysophosphatidic acid (LPA) receptor signaling has been implicated in cardiovascular and obesity-related metabolic disease. However, the distribution and regulation of LPA receptors in the myocardium and adipose tissue remain unclear. This study aimed to characterize the mRNA expression of LPA receptors (LPA1-6) in the murine and human myocardium and adipose tissue, and its regulation in response to obesity. LPA receptor mRNA levels were determined by qPCR in i) heart ventricles, isolated cardiomyocytes, and perigonadal adipose tissue from chow or high fat-high sucrose (HFHS)-fed male C57BL/6 mice, ii) 3T3-L1 adipocytes and HL-1 cardiomyocytes under conditions mimicking gluco/lipotoxicity, and iii) human atrial and subcutaneous adipose tissue from non-obese, pre-obese, and obese cardiac surgery patients. LPA1-6 were expressed in myocardium and white adipose tissue from mice and humans, except for LPA3, which was undetectable in murine adipocytes and human adipose tissue. Obesity was associated with increased LPA4, LPA5 and/or LPA6 levels in mice ventricles and cardiomyocytes, HL-1 cells exposed to high palmitate, and human atrial tissue. LPA4 and LPA5 mRNA levels in human atrial tissue correlated with measures of obesity. LPA5 mRNA levels were increased in HFHS-fed mice and insulin resistant adipocytes, yet were reduced in adipose tissue from obese patients. LPA4, LPA5, and LPA6 mRNA levels in human adipose tissue were negatively associated with measures of obesity and cardiac surgery outcomes. This study suggests that obesity leads to marked changes in LPA receptor expression in the murine and human heart and white adipose tissue that may alter LPA receptor signaling during obesity.

X-ray phase contrast imaging of the breast: Analysis of tissue simulating materials

DOE Office of Scientific and Technical Information (OSTI.GOV)

Vedantham, Srinivasan; Karellas, Andrew

Purpose: Phase contrast imaging, particularly of the breast, is being actively investigated. The purpose of this work is to investigate the x-ray phase contrast properties of breast tissues and commonly used breast tissue substitutes or phantom materials with an aim of determining the phantom materials best representative of breast tissues. Methods: Elemental compositions of breast tissues including adipose, fibroglandular, and skin were used to determine the refractive index, n= 1 -{delta}+i {beta}. The real part of the refractive index, specifically the refractive index decrement ({delta}), over the energy range of 5-50 keV were determined using XOP software (version 2.3, Europeanmore » Synchrotron Radiation Facility, France). Calcium oxalate and calcium hydroxyapatite were considered to represent the material compositions of microcalcifications in vivo. Nineteen tissue substitutes were considered as possible candidates to represent adipose tissue, fibroglandular tissue and skin, and four phantom materials were considered as possible candidates to represent microcalcifications. For each material, either the molecular formula, if available, or the elemental composition based on weight fraction, was used to determine {delta}. At each x-ray photon energy, the absolute percent difference in {delta} between the breast tissue and the substitute material was determined, from which three candidates were selected. From these candidate tissue substitutes, the material that minimized the absolute percent difference in linear attenuation coefficient {mu}, and hence {beta}, was considered to be best representative of that breast tissue. Results: Over the energy range of 5-50 keV, while the {delta} of CB3 and fibroglandular tissue-equivalent material were within 1% of that of fibroglandular tissue, the {mu} of fibroglandular tissue-equivalent material better approximated the fibroglandular tissue. While the {delta} of BR10 and adipose tissue-equivalent material were within 1% of that of adipose tissue, the tissue-equivalent material better approximated the adipose tissue in terms of {mu}. Polymethyl methacrylate, a commonly used tissue substitute, exhibited {delta} greater than fibroglandular tissue by {approx}12%. The A-150 plastic closely approximated the skin. Several materials exhibited {delta} between that of adipose and fibroglandular tissue. However, there was an energy-dependent mismatch in terms of equivalent fibroglandular weight fraction between {delta} and {mu} for these materials. For microcalcifications, aluminum and calcium carbonate were observed to straddle the {delta} and {mu} of calcium oxalate and calcium hydroxyapatite. Aluminum oxide, commonly used to represent microcalcifications in the American College of Radiology recommended phantoms for accreditation exhibited {delta} greater than calcium hydroxyapatite by {approx}23%. Conclusions: A breast phantom comprising A-150 plastic to represent the skin, commercially available adipose and fibroglandular tissue-equivalent formulations to represent adipose and fibroglandular tissue, respectively, was found to be best suited for x-ray phase-sensitive imaging of the breast. Calcium carbonate or aluminum can be used to represent microcalcifications.« less

X-ray phase contrast imaging of the breast: Analysis of tissue simulating materials1

PubMed Central

Vedantham, Srinivasan; Karellas, Andrew

2013-01-01

Purpose: Phase contrast imaging, particularly of the breast, is being actively investigated. The purpose of this work is to investigate the x-ray phase contrast properties of breast tissues and commonly used breast tissue substitutes or phantom materials with an aim of determining the phantom materials best representative of breast tissues. Methods: Elemental compositions of breast tissues including adipose, fibroglandular, and skin were used to determine the refractive index, n = 1 − δ + i β. The real part of the refractive index, specifically the refractive index decrement (δ), over the energy range of 5–50 keV were determined using XOP software (version 2.3, European Synchrotron Radiation Facility, France). Calcium oxalate and calcium hydroxyapatite were considered to represent the material compositions of microcalcifications in vivo. Nineteen tissue substitutes were considered as possible candidates to represent adipose tissue, fibroglandular tissue and skin, and four phantom materials were considered as possible candidates to represent microcalcifications. For each material, either the molecular formula, if available, or the elemental composition based on weight fraction, was used to determine δ. At each x-ray photon energy, the absolute percent difference in δ between the breast tissue and the substitute material was determined, from which three candidates were selected. From these candidate tissue substitutes, the material that minimized the absolute percent difference in linear attenuation coefficient μ, and hence β, was considered to be best representative of that breast tissue. Results: Over the energy range of 5–50 keV, while the δ of CB3 and fibroglandular tissue-equivalent material were within 1% of that of fibroglandular tissue, the μ of fibroglandular tissue-equivalent material better approximated the fibroglandular tissue. While the δ of BR10 and adipose tissue-equivalent material were within 1% of that of adipose tissue, the tissue-equivalent material better approximated the adipose tissue in terms of μ. Polymethyl methacrylate, a commonly used tissue substitute, exhibited δ greater than fibroglandular tissue by ∼12%. The A-150 plastic closely approximated the skin. Several materials exhibited δ between that of adipose and fibroglandular tissue. However, there was an energy-dependent mismatch in terms of equivalent fibroglandular weight fraction between δ and μ for these materials. For microcalcifications, aluminum and calcium carbonate were observed to straddle the δ and μ of calcium oxalate and calcium hydroxyapatite. Aluminum oxide, commonly used to represent microcalcifications in the American College of Radiology recommended phantoms for accreditation exhibited δ greater than calcium hydroxyapatite by ∼23%. Conclusions: A breast phantom comprising A-150 plastic to represent the skin, commercially available adipose and fibroglandular tissue-equivalent formulations to represent adipose and fibroglandular tissue, respectively, was found to be best suited for x-ray phase-sensitive imaging of the breast. Calcium carbonate or aluminum can be used to represent microcalcifications. PMID:23556900

Increased asthma and adipose tissue inflammatory gene expression with obesity and Inuit migration to a western country.

PubMed

Backer, Vibeke; Baines, Katherine J; Powell, Heather; Porsbjerg, Celeste; Gibson, Peter G

2016-02-01

An overlap between obesity and asthma exists, and inflammatory cells in adipose tissue could drive the development of asthma. Comparison of adipose tissue gene expression among Inuit living in Greenland to those in Denmark provides an opportunity to assess how changes in adipose tissue inflammation can be modified by migration and diet. To examine mast cell and inflammatory markers in adipose tissue and the association with asthma. Two Inuit populations were recruited, one living in Greenland and another in Denmark. All underwent adipose subcutaneous biopsy, followed by clinical assessment of asthma, and measurement of AHR. Adipose tissue biopsies were homogenised, RNA extracted, and PCR was performed to determine the relative gene expression of mast cell (tryptase, chymase, CPA3) and inflammatory markers (IL-6, IL-1β, and CD163). Of the 1059 Greenlandic Inuit participants, 556 were living in Greenland and 6.4% had asthma. Asthma was increased in Denmark (9%) compared to Greenland (3.6%, p < 0.0001) and associated with increased adipose tissue IL-6 gene expression and increased BMI. There was no association between asthma and adipose tissue mast cell gene expression. Pro-inflammatory gene expression (IL-6, IL-1β) was higher in those living in Denmark, and with increasing BMI and dietary changes. The anti-inflammatory (M2) macrophage marker, CD163, was higher in Greenland-dwelling Inuit (p < 0.01). No association was found between gene expression of mast cell markers in adipose tissue and asthma. Among Greenlandic Inuit, adipose tissue inflammation is also increased in those who migrate to Denmark, possibly as a result of dietary changes. Copyright © 2015 Elsevier Ltd. All rights reserved.

The sexually dimorphic role of adipose and adipocyte estrogen receptors in modulating adipose tissue expansion, inflammation, and fibrosis

PubMed Central

Davis, Kathryn E.; D. Neinast, Michael; Sun, Kai; M. Skiles, William; D. Bills, Jessica; A. Zehr, Jordan; Zeve, Daniel; D. Hahner, Lisa; W. Cox, Derek; M. Gent, Lana; Xu, Yong; V. Wang, Zhao; A. Khan, Sohaib; Clegg, Deborah J.

2013-01-01

Our data demonstrate that estrogens, estrogen receptor-α (ERα), and estrogen receptor-β (ERβ) regulate adipose tissue distribution, inflammation, fibrosis, and glucose homeostasis, by determining that αERKO mice have increased adipose tissue inflammation and fibrosis prior to obesity onset. Selective deletion of adipose tissue ERα in adult mice using a novel viral vector technology recapitulated the findings in the total body ERα null mice. Generation of a novel mouse model, lacking ERα specifically from adipocytes (AdipoERα), demonstrated increased markers of fibrosis and inflammation, especially in the males. Additionally, we found that the beneficial effects of estrogens on adipose tissue require adipocyte ERα. Lastly, we determined the role of ERβ in regulating inflammation and fibrosis, by breeding the AdipoERα into the βERKO background and found that in the absence of adipocyte ERα, ERβ has a protective role. These data suggest that adipose tissue and adipocyte ERα protects against adiposity, inflammation, and fibrosis in both males and females. PMID:24049737

A correlation between the weight of visceral adipose tissue and selected anthropometric indices: an autopsy study.

PubMed

Edston, E

2013-06-01

Several anthropometric indices are used as an estimation of the true amount of body fat, e.g. the body mass index (BMI). These indices correlate well with each other and with non-invasive measurements of total body fat and visceral adipose tissue. The indices generally show a strong correlation with cardiovascular disease and diabetes mellitus. Direct measurement of visceral adipose tissue by weight (VAW) from autopsy cases positively correlates with the anthropometric indices. VAW also positively correlates with fatty tissue thickness at separate locations, i.e. renal capsular and epicardial fatty tissue. VAW is positively correlated with the severity of cardiosclerosis and diabetes mellitus, but there is no significant difference in VAW between deaths from cardiovascular complications and other natural deaths. Different anthropometric indices and non-invasive methods have been used to estimate the total burden of body fat. Increased visceral adipose tissue is believed to involve elevated risk for cardiovascular disease, type 2 diabetes, chronic kidney disease and hypertension. At present, the optimal method to estimate the visceral and total amount of fat remains undecided. In the present study of 201 autopsy cases, direct measurement of visceral adipose tissue by weight (VAW) has been compared to common anthropometric indices, namely body mass index (BMI), waist-to-hip ratio (W/Hip ratio), waist-to-height ratio (W/Height ratio), body adiposity index (BAI), waist circumference and abdominal wall thickness. The prevalence and severity of cardiovascular disease, diabetes mellitus and cause of death were also correlated with the anthropometric data. The outcome was that all anthropometric measurements showed a significant positive correlation with the weight of visceral adipose tissue, and the r-value of the comparison to waist circumference was the highest (r = 0.82). Thickness of fatty tissue enveloping the kidneys and heart, as well as heart weight, was also strongly correlated with VAW. VAW was significantly higher in men compared with women, and in diabetes mellitus compared with non-diabetic patients. VAW was also positively correlated with the severity of coronary artery sclerosis. On the contrary, there was no significant difference between high and low VAW comparing between deaths from cardiovascular complications and natural deaths from other causes. The conclusion is that the anthropometric measurements give a good approximation of the real amount of visceral fat, and that waist circumference and W/Height ratio show the best correlations. © 2013 The Author. Clinical Obesity © 2013 International Association for the Study of Obesity.

Potential Effects of Aerobic Exercise on the Expression of Perilipin 3 in the Adipose Tissue of Women with Polycystic Ovary Syndrome: A Pilot Study

PubMed Central

Covington, Jeffrey D.; Bajpeyi, Sudip; Moro, Cedric; Tchoukalova, Yourka D.; Ebenezer, Philip J.; Burk, David H.; Ravussin, Eric; Redman, Leanne M.

2014-01-01

Objective Polycystic Ovary Syndrome (PCOS) is associated with reduced adipose tissue lipolysis that can be rescued by aerobic exercise. We aimed to identify differences in gene expression of perilipins and associated targets in adipose tissue in women with PCOS before and after exercise. Design and Methods We conducted a cross-sectional study in 8 women with PCOS and 8 women matched for BMI and age with normal cycles. Women with PCOS also completed a 16-week prospective aerobic exercise-training study. Abdominal subcutaneous adipose tissue biopsies were collected, and primary adipose-derived stromal/stem cell cultures were established from women with PCOS before 16 weeks of aerobic exercise training (n=5) and controls (n=5). Gene expression was measured using real time PCR, in vitro lipolysis was measured using radiolabeled oleate, and PLIN3 protein content was measured by western blotting. Results The expression of PLIN1, PLIN3, and PLIN5, along with coatomers ARF1, ARFRP1, and βCOP were ~80% lower in women with PCOS (all p<0.05). Following exercise training, PLIN3 was the only perilipin to increase significantly (p<0.05), along with coatomers ARF1, ARFRP1, βCOP, and Sec23a (all p<0.05). Furthermore, PLIN3 protein expression was undetectable in the cell cultures from women with PCOS vs. controls. Following exercise training, in vitro adipose oleate oxidation, glycerol secretion, and PLIN3 protein expression were increased, along with reductions in triglyceride content and absence of large lipid droplet morphology. Conclusions These findings suggest that PLIN3 and coatomer GTPases are important regulators of lipolysis and triglyceride storage in the adipose tissue of women with PCOS. PMID:25342854

AKR1C3-Mediated Adipose Androgen Generation Drives Lipotoxicity in Women With Polycystic Ovary Syndrome

PubMed Central

O’Reilly, Michael W.; Kempegowda, Punith; Walsh, Mark; Taylor, Angela E.; Manolopoulos, Konstantinos N.; Allwood, J. William; Semple, Robert K.; Hebenstreit, Daniel; Dunn, Warwick B.; Tomlinson, Jeremy W.

2017-01-01

Context: Polycystic ovary syndrome (PCOS) is a prevalent metabolic disorder occurring in up to 10% of women of reproductive age. PCOS is associated with insulin resistance and cardiovascular risk. Androgen excess is a defining feature of PCOS and has been suggested as causally associated with insulin resistance; however, mechanistic evidence linking both is lacking. We hypothesized that adipose tissue is an important site linking androgen activation and metabolic dysfunction in PCOS. Methods: We performed a human deep metabolic in vivo phenotyping study examining the systemic and intra-adipose effects of acute and chronic androgen exposure in 10 PCOS women, in comparison with 10 body mass index–matched healthy controls, complemented by in vitro experiments. Results: PCOS women had increased intra-adipose concentrations of testosterone (P = 0.0006) and dihydrotestosterone (P = 0.01), with increased expression of the androgen-activating enzyme aldo-ketoreductase type 1 C3 (AKR1C3) (P = 0.04) in subcutaneous adipose tissue. Adipose glycerol levels in subcutaneous adipose tissue microdialysate supported in vivo suppression of lipolysis after acute androgen exposure in PCOS (P = 0.04). Mirroring this, nontargeted serum metabolomics revealed prolipogenic effects of androgens in PCOS women only. In vitro studies showed that insulin increased adipose AKR1C3 expression and activity, whereas androgen exposure increased adipocyte de novo lipid synthesis. Pharmacologic AKR1C3 inhibition in vitro decreased de novo lipogenesis. Conclusions: These findings define an intra-adipose mechanism of androgen activation that contributes to adipose remodeling and a systemic lipotoxic metabolome, with intra-adipose androgens driving lipid accumulation and insulin resistance in PCOS. AKR1C3 represents a promising therapeutic target in PCOS. PMID:28645211

Isoliquiritigenin Attenuates Adipose Tissue Inflammation in vitro and Adipose Tissue Fibrosis through Inhibition of Innate Immune Responses in Mice.

PubMed

Watanabe, Yasuharu; Nagai, Yoshinori; Honda, Hiroe; Okamoto, Naoki; Yamamoto, Seiji; Hamashima, Takeru; Ishii, Yoko; Tanaka, Miyako; Suganami, Takayoshi; Sasahara, Masakiyo; Miyake, Kensuke; Takatsu, Kiyoshi

2016-03-15

Isoliquiritigenin (ILG) is a flavonoid derived from Glycyrrhiza uralensis and potently suppresses NLRP3 inflammasome activation resulting in the improvement of diet-induced adipose tissue inflammation. However, whether ILG affects other pathways besides the inflammasome in adipose tissue inflammation is unknown. We here show that ILG suppresses adipose tissue inflammation by affecting the paracrine loop containing saturated fatty acids and TNF-α by using a co-culture composed of adipocytes and macrophages. ILG suppressed inflammatory changes induced by the co-culture through inhibition of NF-κB activation. This effect was independent of either inhibition of inflammasome activation or activation of peroxisome proliferator-activated receptor-γ. Moreover, ILG suppressed TNF-α-induced activation of adipocytes, coincident with inhibition of IκBα phosphorylation. Additionally, TNF-α-mediated inhibition of Akt phosphorylation under insulin signaling was alleviated by ILG in adipocytes. ILG suppressed palmitic acid-induced activation of macrophages, with decreasing the level of phosphorylated Jnk expression. Intriguingly, ILG improved high fat diet-induced fibrosis in adipose tissue in vivo. Finally, ILG inhibited TLR4- or Mincle-stimulated expression of fibrosis-related genes in stromal vascular fraction from obese adipose tissue and macrophages in vitro. Thus, ILG can suppress adipose tissue inflammation by both inflammasome-dependent and -independent manners and attenuate adipose tissue fibrosis by targeting innate immune sensors.

Obesity-induced endoplasmic reticulum stress causes chronic inflammation in adipose tissue.

PubMed

Kawasaki, Noritaka; Asada, Rie; Saito, Atsushi; Kanemoto, Soshi; Imaizumi, Kazunori

2012-01-01

Adipose tissue plays a central role in maintaining metabolic homeostasis under normal conditions. Metabolic diseases such as obesity and type 2 diabetes are often accompanied by chronic inflammation and adipose tissue dysfunction. In this study, we observed that endoplasmic reticulum (ER) stress and the inflammatory response occurred in adipose tissue of mice fed a high-fat diet for a period of 16 weeks. After 16 weeks of feeding, ER stress markers increased and chronic inflammation occurred in adipose tissue. We found that ER stress is induced by free fatty acid (FFA)-mediated reactive oxygen species (ROS) generation and up-regulated gene expression of inflammatory cytokines in 3T3-L1 adipocytes. Oral administration to obese mice of chemical chaperons, which alleviate ER stress, improved chronic inflammation in adipose tissue, followed by the suppression of increased body weight and improved insulin signaling. These results indicate that ER stress plays important pathophysiological roles in obesity-induced adipose tissue dysfunction.

Heterogeneity of human adipose blood flow

PubMed Central

Levitt, David G

2007-01-01

Background The long time pharmacokinetics of highly lipid soluble compounds is dominated by blood-adipose tissue exchange and depends on the magnitude and heterogeneity of adipose blood flow. Because the adipose tissue is an infinite sink at short times (hours), the kinetics must be followed for days in order to determine if the adipose perfusion is heterogeneous. The purpose of this paper is to quantitate human adipose blood flow heterogeneity and determine its importance for human pharmacokinetics. Methods The heterogeneity was determined using a physiologically based pharmacokinetic model (PBPK) to describe the 6 day volatile anesthetic data previously published by Yasuda et. al. The analysis uses the freely available software PKQuest and incorporates perfusion-ventilation mismatch and time dependent parameters that varied from the anesthetized to the ambulatory period. This heterogeneous adipose perfusion PBPK model was then tested by applying it to the previously published cannabidiol data of Ohlsson et. al. and the cannabinol data of Johansson et. al. Results The volatile anesthetic kinetics at early times have only a weak dependence on adipose blood flow while at long times the pharmacokinetics are dominated by the adipose flow and are independent of muscle blood flow. At least 2 adipose compartments with different perfusion rates (0.074 and 0.014 l/kg/min) were needed to describe the anesthetic data. This heterogeneous adipose PBPK model also provided a good fit to the cannabinol data. Conclusion Human adipose blood flow is markedly heterogeneous, varying by at least 5 fold. This heterogeneity significantly influences the long time pharmacokinetics of the volatile anesthetics and tetrahydrocannabinol. In contrast, using this same PBPK model it can be shown that the long time pharmacokinetics of the persistent lipophilic compounds (dioxins, PCBs) do not depend on adipose blood flow. The ability of the same PBPK model to describe both the anesthetic and cannabinol kinetics provides direct qualitative evidence that their kinetics are flow limited and that there is no significant adipose tissue diffusion limitation. PMID:17239252

Retinoic acid receptor-related orphan receptor α stimulates adipose tissue inflammation by modulating endoplasmic reticulum stress.

PubMed

Liu, Yin; Chen, Yulong; Zhang, Jinlong; Liu, Yulan; Zhang, Yanjie; Su, Zhiguang

2017-08-25

Adipose tissue inflammation has been linked to metabolic diseases such as obesity and type 2 diabetes. However, the molecules that mediate inflammation in adipose tissue have not been addressed. Although retinoic acid receptor-related orphan receptor α (RORα) is known to be involved in the regulation of inflammatory response in some tissues, its role is largely unknown in adipose tissue. Conversely, it is known that endoplasmic reticulum (ER) stress and unfolding protein response (UPR) signaling affect the inflammatory response in obese adipose tissue, but whether RORα regulates these processes remains unknown. In this study, we investigate the link between RORα and adipose tissue inflammation. We showed that the inflammatory response in macrophages or 3T3-L1 adipocytes stimulated by lipopolysaccharide, as well as adipose tissue in obese mice, markedly increased the expression of RORα. Adenovirus-mediated overexpression of RORα or treatment with the RORα-specific agonist SR1078 enhanced the expression of inflammatory cytokines and increased the number of infiltrated macrophages into adipose tissue. Furthermore, SR1078 up-regulated the mRNA expression of ER stress response genes and enhanced phosphorylations of two of the three mediators of major UPR signaling pathways, PERK and IRE1α. Finally, we found that alleviation of ER stress using a chemical chaperone followed by the suppression of RORα induced inflammation in adipose tissue. Our data suggest that RORα-induced ER stress response potentially contributes to the adipose tissue inflammation that can be mitigated by treatment with chemical chaperones. The relationships established here between RORα expression, inflammation, and UPR signaling may have implications for therapeutic targeting of obesity-related metabolic diseases. © 2017 by The American Society for Biochemistry and Molecular Biology, Inc.

Biomimetic 3D tissue printing for soft tissue regeneration.

PubMed

Pati, Falguni; Ha, Dong-Heon; Jang, Jinah; Han, Hyun Ho; Rhie, Jong-Won; Cho, Dong-Woo

2015-09-01

Engineered adipose tissue constructs that are capable of reconstructing soft tissue with adequate volume would be worthwhile in plastic and reconstructive surgery. Tissue printing offers the possibility of fabricating anatomically relevant tissue constructs by delivering suitable matrix materials and living cells. Here, we devise a biomimetic approach for printing adipose tissue constructs employing decellularized adipose tissue (DAT) matrix bioink encapsulating human adipose tissue-derived mesenchymal stem cells (hASCs). We designed and printed precisely-defined and flexible dome-shaped structures with engineered porosity using DAT bioink that facilitated high cell viability over 2 weeks and induced expression of standard adipogenic genes without any supplemented adipogenic factors. The printed DAT constructs expressed adipogenic genes more intensely than did non-printed DAT gel. To evaluate the efficacy of our printed tissue constructs for adipose tissue regeneration, we implanted them subcutaneously in mice. The constructs did not induce chronic inflammation or cytotoxicity postimplantation, but supported positive tissue infiltration, constructive tissue remodeling, and adipose tissue formation. This study demonstrates that direct printing of spatially on-demand customized tissue analogs is a promising approach to soft tissue regeneration. Copyright © 2015 Elsevier Ltd. All rights reserved.

Androgen Effects on Adipose Tissue Architecture and Function in Nonhuman Primates

PubMed Central

Varlamov, Oleg; White, Ashley E.; Carroll, Julie M.; Bethea, Cynthia L.; Reddy, Arubala; Slayden, Ov; O'Rourke, Robert W.

2012-01-01

The differential association of hypoandrogenism in men and hyperandrogenism in women with insulin resistance and obesity suggests that androgens may exert sex-specific effects on adipose and other tissues, although the underlying mechanisms remain poorly understood. Moreover, recent studies also suggest that rodents and humans may respond differently to androgen imbalance. To achieve better insight into clinically relevant sex-specific mechanisms of androgen action, we used nonhuman primates to investigate the direct effects of gonadectomy and hormone replacement on white adipose tissue. We also employed a novel ex vivo approach that provides a convenient framework for understanding of adipose tissue physiology under a controlled tissue culture environment. In vivo androgen deprivation of males did not result in overt obesity or insulin resistance but did induce the appearance of very small, multilocular white adipocytes. Testosterone replacement restored normal cell size and a unilocular phenotype and stimulated adipogenic gene transcription and improved insulin sensitivity of male adipose tissue. Ex vivo studies demonstrated sex-specific effects of androgens on adipocyte function. Female adipose tissue treated with androgens displayed elevated basal but reduced insulin-dependent fatty acid uptake. Androgen-stimulated basal uptake was greater in adipose tissue of ovariectomized females than in adipose tissue of intact females and ovariectomized females replaced with estrogen and progesterone in vivo. Collectively, these data demonstrate that androgens are essential for normal adipogenesis in males and can impair essential adipocyte functions in females, thus strengthening the experimental basis for sex-specific effects of androgens in adipose tissue. PMID:22547568

Estrogen receptor 1 (ESR1) regulates VEGFA in adipose tissue.

PubMed

Fatima, L A; Campello, R S; Santos, R de Souza; Freitas, H S; Frank, A P; Machado, U F; Clegg, D J

2017-12-01

Vascular endothelial growth factor A (VEGFA) is a key factor in the regulation of angiogenesis in adipose tissue. Poor vascularization during adipose tissue proliferation causes fibrosis and local inflammation, and is associated with insulin resistance. It is known that 17-beta estradiol (E2) regulates adipose tissue function and VEGFA expression in other tissues; however, the ability of E2 to regulate VEGFA in adipose tissue is currently unknown. In this study, we showed that, in 3T3-L1 cells, E2 and the estrogen receptor 1 (ESR1) agonist PPT induced VEGFA expression, while ESR1 antagonist (MPP), and selective knockdown of ESR1 using siRNA decreased VEGFA and prevented the ability of E2 to modulate its expression. Additionally, we found that E2 and PPT induced the binding of hypoxia inducible factor 1 alpha subunit (HIF1A) in the VEGFA gene promoter. We further found that VEGFA expression was lower in inguinal and gonadal white adipose tissues of ESR1 total body knockout female mice compared to wild type mice. In conclusion, our data provide evidence of an important role for E2/ESR1 in modulating adipose tissue VEGFA, which is potentially important to enhance angiogenesis, reduce inflammation and improve adipose tissue function.

Anatomy and histology of the newly discovered adipose sac structure within the labia majora: international original research.

PubMed

Ostrzenski, Adam; Krajewski, Pawel; Davis, Kern

2016-09-01

To determine whether there is any new anatomical structure present within the labia majora. A case serial study was executed on eleven consecutive fresh human female cadavers. Stratum-by-stratum dissections of the labia majora were performed. Twenty-two anatomic dissections of labia majora were completed. Eosin and Hematoxylin agents were used to stain newly discovered adipose sac's tissues of the labia majora and the cylinder-like structures, which cover condensed adipose tissues. The histology of these two structures was compared. All dissected labia majora demonstrated the presence of the anatomic existence of the adipose sac structure. Just under the dermis of the labia majora, the adipose sac was located, which was filled with lobules containing condensed fatty tissues in the form of cylinders. The histological investigation established that the well-organized fibro-connective-adipose tissues represented the adipose sac. The absence of descriptions of the adipose sac within the labia majora in traditional anatomic and gynecologic textbooks was noted. In this study group, the newly discovered adipose sac is consistently present within the anatomical structure of the labia majora. The well-organized fibro-connective-adipose tissue represents microscopic characteristic features of the adipose sac.

Regulatory iNKT cells lack expression of the transcription factor PLZF and control the homeostasis of T(reg) cells and macrophages in adipose tissue.

PubMed

Lynch, Lydia; Michelet, Xavier; Zhang, Sai; Brennan, Patrick J; Moseman, Ashley; Lester, Chantel; Besra, Gurdyal; Vomhof-Dekrey, Emilie E; Tighe, Mike; Koay, Hui-Fern; Godfrey, Dale I; Leadbetter, Elizabeth A; Sant'Angelo, Derek B; von Andrian, Ulrich; Brenner, Michael B

2015-01-01

Invariant natural killer T cells (iNKT cells) are lipid-sensing innate T cells that are restricted by the antigen-presenting molecule CD1d and express the transcription factor PLZF. iNKT cells accumulate in adipose tissue, where they are anti-inflammatory, but the factors that contribute to their anti-inflammatory nature, as well as their targets in adipose tissue, are unknown. Here we found that iNKT cells in adipose tissue had a unique transcriptional program and produced interleukin 2 (IL-2) and IL-10. Unlike other iNKT cells, they lacked PLZF but expressed the transcription factor E4BP4, which controlled their IL-10 production. The adipose iNKT cells were a tissue-resident population that induced an anti-inflammatory phenotype in macrophages and, through the production of IL-2, controlled the number, proliferation and suppressor function of regulatory T cells (Treg cells) in adipose tissue. Thus, iNKT cells in adipose tissue are unique regulators of immunological homeostasis in this tissue.

Osteochondral tissue formation through adipose-derived stromal cell differentiation on biomimetic polycaprolactone nanofibrous scaffolds with graded insulin and Beta-glycerophosphate concentrations.

PubMed

Erisken, Cevat; Kalyon, Dilhan M; Wang, Hongjun; Ornek-Ballanco, Ceren; Xu, Jiahua

2011-05-01

The ability to fabricate tissue engineering scaffolds containing systematic gradients in the distributions of stimulators provides additional means for the mimicking of the important gradients observed in native tissues. Here the concentration distributions of two bioactive agents were varied concomitantly for the first time (one increasing, whereas the other decreasing monotonically) in between the two sides of a nanofibrous scaffold. This was achieved via the application of a new processing method, that is, the twin-screw extrusion and electrospinning method, to generate gradients of insulin, a stimulator of chondrogenic differentiation, and β-glycerophosphate (β-GP), for mineralization. The graded poly(ɛ-caprolactone) mesh was seeded with human adipose-derived stromal cells and cultured over 8 weeks. The resulting tissue constructs were analyzed for and revealed indications of selective differentiation of human adipose-derived stromal cells toward chondrogenic lineage and mineralization as functions of position as a result of the corresponding concentrations of insulin and β-GP. Chondrogenic differentiation of the stem cells increased at insulin-rich locations and mineralization increased at β-GP-rich locations.

Sugar-Sweetened Beverage Consumption is Associated With Change of Visceral Adipose Tissue Over 6 Years of Follow-Up

PubMed Central

Ma, Jiantao; McKeown, Nicola M.; Hwang, Shih-Jen; Hoffmann, Udo; Jacques, Paul F.; Fox, Caroline S.

2015-01-01

Background Sugar-sweetened beverage (SSB) intake has been linked to abnormal abdominal adipose tissue. We examined the prospective association of habitual SSB intake and change in visceral adipose tissue (VAT) and subcutaneous adipose tissue (SAT). Methods and Results The quantity (volume, cm3) and quality (attenuation, Hounsfield Unit) of abdominal adipose tissue were measured using computed tomography in 1,003 participants (mean age 45.3 years, 45.0% women) at exam 1 and 2 in the Framingham’s Third Generation cohort. The 2 exams were approximately 6 years apart. At baseline, SSB and diet soda intake were assessed using a valid food frequency questionnaire. Participants were categorized into 4 groups: none to <1 serving/month (non-consumers), 1 serving/month to <1 serving/week, 1 serving/week to 1 serving/day, and ≥1 serving/day (daily consumers) of either SSB or diet soda. After adjustment for multiple confounders including change in body weight, higher SSB intake was associated with greater change in VAT volume (P-trend<0.001). VAT volume increased by 658 cm3 (95%CI: 602–713), 649 cm3 (95%CI: 582–716), 707 cm3 (95%CI: 657–757), and 852 cm3 (95%CI: 760–943) from non-consumers to daily consumers. Higher SSB intake was also associated with greater decline of VAT attenuation (P-trend=0.007); however, the association became non-significant after additional adjustment for VAT volume change. In contrast, diet soda consumption was not associated with change in abdominal adipose tissue. Conclusions Regular SSB intake was associated with adverse change in both VAT quality and quantity, whereas we observed no such association for diet soda. PMID:26755505

Body fat mass and the proportion of very large adipocytes in pregnant women are associated with gestational insulin resistance

PubMed Central

Svensson, H; Wetterling, L; Bosaeus, M; Odén, B; Odén, A; Jennische, E; Edén, S; Holmäng, A; Lönn, M

2016-01-01

Background/Objectives: Pregnancy is accompanied by fat gain and insulin resistance. Changes in adipose tissue morphology and function during pregnancy and factors contributing to gestational insulin resistance are incompletely known. We sought to characterize adipose tissue in trimesters 1 and 3 (T1/T3) in normal weight (NW) and obese pregnant women, and identify adipose tissue-related factors associated with gestational insulin resistance. Subjects/Methods: Twenty-two NW and 11 obese women were recruited early in pregnancy for the Pregnancy Obesity Nutrition and Child Health study. Examinations and sampling of blood and abdominal adipose tissue were performed longitudinally in T1/T3 to determine fat mass (air-displacement plethysmography); insulin resistance (homeostasis model assessment of insulin resistance, HOMA-IR); size, number and lipolytic activity of adipocytes; and adipokine release and density of immune cells and blood vessels in adipose tissue. Results: Fat mass and HOMA-IR increased similarly between T1 and T3 in the groups; all remained normoglycemic. Adipocyte size increased in NW women. Adipocyte number was not influenced, but proportions of small and large adipocytes changed oppositely in the groups. Lipolytic activity and circulating adipocyte fatty acid-binding protein increased in both groups. Adiponectin release was reduced in NW women. Fat mass and the proportion of very large adipocytes were most strongly associated with T3 HOMA-IR by multivariable linear regression (R2=0.751, P<0.001). Conclusions: During pregnancy, adipose tissue morphology and function change comprehensively. NW women accumulated fat in existing adipocytes, accompanied by reduced adiponectin release. In comparison with the NW group, obese women had signs of adipocyte recruitment and maintained adiponectin levels. Body fat and large adipocytes may contribute significantly to gestational insulin resistance. PMID:26563815

Determination of d-limonene in adipose tissue by gas chromatography-mass spectrometry

PubMed Central

Miller, Jessica A.; Hakim, Iman A.; Thomson, Cynthia; Thompson, Patricia; Chow, H-H. Sherry

2008-01-01

We developed a novel method for analyzing d-limonene levels in adipose tissue. Fat samples were subjected to saponification followed by solvent extraction. d-Limonene in the sample extract was analyzed using gas chromatography-mass spectrometry (GC-MS) with selected ion monitoring. Linear calibration curves were established over the mass range of 79.0-2,529 ng d-limonene per 0.1 grams of adipose tissue. Satisfactory within day precision (RSD 6.7 to 9.6%) and accuracy (% difference of −2.7 to 3.8%) and between day precision (RSD 6.0 to 10.7%) and accuracy (% difference of 1.8 to 2.6%) were achieved. The assay was successfully applied to human fat biopsy samples from a d-limonene feeding trial. PMID:18571481

Brown adipose tissue

PubMed Central

Townsend, Kristy; Tseng, Yu-Hua

2012-01-01

Obesity is currently a global pandemic, and is associated with increased mortality and co-morbidities including many metabolic diseases. Obesity is characterized by an increase in adipose mass due to increased energy intake, decreased energy expenditure, or both. While white adipose tissue is specialized for energy storage, brown adipose tissue has a high concentration of mitochondria and uniquely expresses uncoupling protein 1, enabling it to be specialized for energy expenditure and thermogenesis. Although brown fat was once considered only necessary in babies, recent morphological and imaging studies have provided evidence that, contrary to prior belief, this tissue is present and active in adult humans. In recent years, the topic of brown adipose tissue has been reinvigorated with many new studies regarding brown adipose tissue differentiation, function and therapeutic promise. This review summarizes the recent advances, discusses the emerging questions and offers perspective on the potential therapeutic applications targeting this tissue. PMID:23700507

Identification of a Lipokine, a Lipid Hormone Linking Adipose Tissue to Systemic Metabolism

PubMed Central

Cao, Haiming; Gerhold, Kristin; Mayers, Jared R.; Wiest, Michelle M.; Watkins, Steve M.; Hotamisligil, Gökhan S.

2008-01-01

Dysregulation of lipid metabolism in individual tissues can lead to systemic disruption of insulin action and glucose metabolism. Utilizing a comprehensive lipidomic platform and mice deficient in adipose tissue lipid chaperones aP2 and mal1, we explored how metabolic alterations in adipose tissue are linked to whole-body metabolism through lipid signals. A robust increase in de novo lipogenesis rendered the adipose tissue of these mice resistant to the deleterious systemic effects of dietary lipid exposure. Systemic lipid profiling also led to identification of C16:1n7-palmitoleate as an adipose tissue-derived lipid hormone that strongly stimulates muscle insulin action and suppresses hepatosteatosis. Our data reveal a novel, lipid-mediated endocrine network and demonstrate that adipose tissue uses lipokines such as C16:1n7-palmitoleate to communicate with distant organs and regulate systemic metabolic homeostasis. PMID:18805087

Defining the Adipose Tissue Proteome of Dairy Cows to Reveal Biomarkers Related to Peripartum Insulin Resistance and Metabolic Status.

PubMed

Zachut, Maya

2015-07-02

Adipose tissue is a central regulator of metabolism in dairy cows; however, little is known about the association between various proteins in adipose tissue and the metabolic status of peripartum cows. Therefore, the objectives were to (1) examine total protein expression in adipose tissue of dairy cows and (2) identify biomarkers in adipose that are linked to insulin resistance and to cows' metabolic status. Adipose tissue biopsies were obtained from eight multiparous cows at -17 and +4 days relative to parturition. Proteins were analyzed by intensity-based, label-free, quantitative shotgun proteomics (nanoLC-MS/MS). Cows were divided into groups with insulin-resistant (IR) and insulin-sensitive (IS) adipose according to protein kinase B phosphorylation following insulin stimulation. Cows with IR adipose lost more body weight postpartum compared with IS cows. Differential expression of 143 out of 586 proteins was detected in prepartum versus postpartum adipose. Comparing IR to IS adipose revealed differential expression of 18.9% of the proteins; those related to lipolysis (hormone-sensitive lipase, perilipin, monoglycerol lipase) were increased in IR adipose. In conclusion, we found novel biomarkers related to IR in adipose and to metabolic status that could be used to characterize high-yielding dairy cows that are better adapted to peripartum metabolic stress.

Matrix-Assisted Transplantation of Functional Beige Adipose Tissue

PubMed Central

Tharp, Kevin M.; Jha, Amit K.; Kraiczy, Judith; Yesian, Alexandra; Karateev, Grigory; Sinisi, Riccardo; Dubikovskaya, Elena A.

2015-01-01

Novel, clinically relevant, approaches to shift energy balance are urgently needed to combat metabolic disorders such as obesity and diabetes. One promising approach has been the expansion of brown adipose tissues that express uncoupling protein (UCP) 1 and thus can uncouple mitochondrial respiration from ATP synthesis. While expansion of UCP1-expressing adipose depots may be achieved in rodents via genetic and pharmacological manipulations or the transplantation of brown fat depots, these methods are difficult to use for human clinical intervention. We present a novel cell scaffold technology optimized to establish functional brown fat–like depots in vivo. We adapted the biophysical properties of hyaluronic acid–based hydrogels to support the differentiation of white adipose tissue–derived multipotent stem cells (ADMSCs) into lipid-accumulating, UCP1-expressing beige adipose tissue. Subcutaneous implantation of ADMSCs within optimized hydrogels resulted in the establishment of distinct UCP1-expressing implants that successfully attracted host vasculature and persisted for several weeks. Importantly, implant recipients demonstrated elevated core body temperature during cold challenges, enhanced respiration rates, improved glucose homeostasis, and reduced weight gain, demonstrating the therapeutic merit of this highly translatable approach. This novel approach is the first truly clinically translatable system to unlock the therapeutic potential of brown fat–like tissue expansion. PMID:26293504

MAP3K8 (TPL2/COT) affects obesity-induced adipose tissue inflammation without systemic effects in humans and in mice.

PubMed

Ballak, Dov B; van Essen, Peter; van Diepen, Janna A; Jansen, Henry; Hijmans, Anneke; Matsuguchi, Tetsuya; Sparrer, Helmut; Tack, Cees J; Netea, Mihai G; Joosten, Leo A B; Stienstra, Rinke

2014-01-01

Chronic low-grade inflammation in adipose tissue often accompanies obesity, leading to insulin resistance and increasing the risk for metabolic diseases. MAP3K8 (TPL2/COT) is an important signal transductor and activator of pro-inflammatory pathways that has been linked to obesity-induced adipose tissue inflammation. We used human adipose tissue biopsies to study the relationship of MAP3K8 expression with markers of obesity and expression of pro-inflammatory cytokines (IL-1β, IL-6 and IL-8). Moreover, we evaluated obesity-induced adipose tissue inflammation and insulin resistance in mice lacking MAP3K8 and WT mice on a high-fat diet (HFD) for 16 weeks. Individuals with a BMI >30 displayed a higher mRNA expression of MAP3K8 in adipose tissue compared to individuals with a normal BMI. Additionally, high mRNA expression levels of IL-1β, IL-6 and IL-8, but not TNF -α, in human adipose tissue were associated with higher expression of MAP3K8. Moreover, high plasma SAA and CRP did not associate with increased MAP3K8 expression in adipose tissue. Similarly, no association was found for MAP3K8 expression with plasma insulin or glucose levels. Mice lacking MAP3K8 had similar bodyweight gain as WT mice, yet displayed lower mRNA expression levels of IL-1β, IL-6 and CXCL1 in adipose tissue in response to the HFD as compared to WT animals. However, MAP3K8 deficient mice were not protected against HFD-induced adipose tissue macrophage infiltration or the development of insulin resistance. Together, the data in both human and mouse show that MAP3K8 is involved in local adipose tissue inflammation, specifically for IL-1β and its responsive cytokines IL-6 and IL-8, but does not seem to have systemic effects on insulin resistance.

Dietary Sodium, Adiposity, and Inflammation in Healthy Adolescents

PubMed Central

Pollock, Norman K.; Kotak, Ishita; Gutin, Bernard; Wang, Xiaoling; Bhagatwala, Jigar; Parikh, Samip; Harshfield, Gregory A.; Dong, Yanbin

2014-01-01

OBJECTIVES: To determine the relationships of sodium intake with adiposity and inflammation in healthy adolescents. METHODS: A cross-sectional study involved 766 healthy white and African American adolescents aged 14 to 18 years. Dietary sodium intake was estimated by 7-day 24-hour dietary recall. Percent body fat was measured by dual-energy x-ray absorptiometry. Subcutaneous abdominal adipose tissue and visceral adipose tissue were assessed using magnetic resonance imaging. Fasting blood samples were measured for leptin, adiponectin, C-reactive protein, tumor necrosis factor-α, and intercellular adhesion molecule-1. RESULTS: The average sodium intake was 3280 mg/day. Ninety-seven percent of our adolescents exceeded the American Heart Association recommendation for sodium intake. Multiple linear regressions revealed that dietary sodium intake was independently associated with body weight (β = 0.23), BMI (β = 0.23), waist circumference (β = 0.23), percent body fat (β = 0.17), fat mass (β = 0.23), subcutaneous abdominal adipose tissue (β = 0.25), leptin (β = 0.20), and tumor necrosis factor-α (β = 0.61; all Ps < .05). No relation was found between dietary sodium intake and visceral adipose tissue, skinfold thickness, adiponectin, C-reactive protein, or intercellular adhesion molecule-1. All the significant associations persisted after correction for multiple testing (all false discovery rates < 0.05). CONCLUSIONS: The mean sodium consumption of our adolescents is as high as that of adults and more than twice the daily intake recommended by the American Heart Association. High sodium intake is positively associated with adiposity and inflammation independent of total energy intake and sugar-sweetened soft drink consumption. PMID:24488738

Neutron organ dose and the influence of adipose tissue

NASA Astrophysics Data System (ADS)

Simpkins, Robert Wayne

Neutron fluence to dose conversion coefficients have been assessed considering the influences of human adipose tissue. Monte Carlo code MCNP4C was used to simulate broad parallel beam monoenergetic neutrons ranging in energy from thermal to 10 MeV. Simulated Irradiations were conducted for standard irradiation geometries. The targets were on gender specific mathematical anthropomorphic phantoms modified to approximate human adipose tissue distributions. Dosimetric analysis compared adipose tissue influence against reference anthropomorphic phantom characteristics. Adipose Male and Post-Menopausal Female Phantoms were derived introducing interstitial adipose tissue to account for 22 and 27 kg additional body mass, respectively, each demonstrating a Body Mass Index (BMI) of 30. An Adipose Female Phantom was derived introducing specific subcutaneous adipose tissue accounting for 15 kg of additional body mass demonstrating a BMI of 26. Neutron dose was shielded in the superficial tissues; giving rise to secondary photons which dominated the effective dose for Incident energies less than 100 keV. Adipose tissue impact on the effective dose was a 25% reduction at the anterior-posterior incidence ranging to a 10% increase at the lateral incidences. Organ dose impacts were more distinctive; symmetrically situated organs demonstrated a 15% reduction at the anterior-posterior Incidence ranging to a 2% increase at the lateral incidences. Abdominal or asymmetrically situated organs demonstrated a 50% reduction at the anterior-posterior incidence ranging to a 25% increase at the lateral incidences.

Liver fat content is linked to inflammatory changes in subcutaneous adipose tissue in type 2 diabetes patients.

PubMed

Jansen, Henry J; Vervoort, Gerald M; van der Graaf, Marinette; Stienstra, Rinke; Tack, Cees J

2013-11-01

Patients with type 2 diabetes mellitus (T2DM) are typically overweight and have an increased liver fat content (LFAT). High LFAT may be explained by an increased efflux of free fatty acids from the adipose tissue, which is partly instigated by inflammatory changes. This would imply an association between inflammatory features of the adipose tissue and liver fat content. To analyse associations between inflammatory features of the adipose tissue and liver fat content. A cross-sectional study. Twenty-seven obese patients with insulin-treated T2DM were studied. LFAT content was measured by proton magnetic resonance spectroscopy. A subcutaneous (sc) fat biopsy was obtained to determine morphology and protein levels within adipose tissue. In addition to fat cell size, the percentage of macrophages and the presence of crown-like structures (CLSs) within sc fat were assessed by CD68-immunohistochemical staining. Mean LFAT percentage was 11·1 ± 1·7% (range: 0·75-32·9%); 63% of the patients were diagnosed with an elevated LFAT (upper range of normal ≤5·5%). Whereas adipocyte size did not correlate with LFAT, 3 of 4 subjects with CLSs in sc fat had elevated LFAT and the percentage of macrophages present in sc adipose tissue was positively associated with LFAT. Protein concentrations of adiponectin within adipose tissue negatively correlated with LFAT. Adipose tissue protein levels of the key inflammatory adipokine plasminogen activator inhibitor-1 (PAI-1) were positively associated with LFAT. Several pro-inflammatory changes in sc adipose tissue associate with increased LFAT content in obese insulin-treated patients with T2DM. These findings suggest that inflammatory changes at the level of the adipose tissue may drive liver fat accumulation. © 2012 John Wiley & Sons Ltd.

Physiological Aging: Links Among Adipose Tissue Dysfunction, Diabetes, and Frailty

PubMed Central

Stout, Michael B.; Justice, Jamie N.; Nicklas, Barbara J.; Kirkland, James L.

2016-01-01

Advancing age is associated with progressive declines in physiological function that lead to overt chronic disease, frailty, and eventual mortality. Importantly, age-related physiological changes occur in cellularity, insulin-responsiveness, secretory profiles, and inflammatory status of adipose tissue, leading to adipose tissue dysfunction. Although the mechanisms underlying adipose tissue dysfunction are multifactorial, the consequences result in secretion of proinflammatory cytokines and chemokines, immune cell infiltration, an accumulation of senescent cells, and an increase in senescence-associated secretory phenotype (SASP). These processes synergistically promote chronic sterile inflammation, insulin resistance, and lipid redistribution away from subcutaneous adipose tissue. Without intervention, these effects contribute to age-related systemic metabolic dysfunction, physical limitations, and frailty. Thus adipose tissue dysfunction may be a fundamental contributor to the elevated risk of chronic disease, disability, and adverse health outcomes with advancing age. PMID:27927801

Metabolic inflammation in inflammatory bowel disease: crosstalk between adipose tissue and bowel.

PubMed

Gonçalves, Pedro; Magro, Fernando; Martel, Fátima

2015-02-01

Epidemiological studies show that both the incidence of inflammatory bowel disease (IBD) and the proportion of people with obesity and/or obesity-associated metabolic syndrome increased markedly in developed countries during the past half century. Obesity is also associated with the development of more active IBD and requirement for hospitalization and with a decrease in the time span between diagnosis and surgery. Patients with IBD, especially Crohn's disease, present fat-wrapping or "creeping fat," which corresponds to ectopic adipose tissue extending from the mesenteric attachment and covering the majority of the small and large intestinal surface. Mesenteric adipose tissue in patients with IBD presents several morphological and functional alterations, e.g., it is more infiltrated with immune cells such as macrophages and T cells. All these lines of evidence clearly show an association between obesity, adipose tissue, and functional bowel disorders. In this review, we will show that the mesenteric adipose tissue and creeping fat are not innocent by standers but actively contribute to the intestinal and systemic inflammatory responses in patients with IBD. More specifically, we will review evidence showing that adipose tissue in IBD is associated with major alterations in the secretion of cytokines and adipokines involved in inflammatory process, in adipose tissue mesenchymal stem cells and adipogenesis, and in the interaction between adipose tissue and other intestinal components (immune, lymphatic, neuroendocrine, and intestinal epithelial systems). Collectively, these studies underline the importance of adipose tissue for the identification of novel therapeutic approaches for IBD.

Reduction of Adipose Tissue Mass by the Angiogenesis Inhibitor ALS-L1023 from Melissa officinalis

PubMed Central

Park, Byung Young; Lee, Hyunghee; Woo, Sangee; Yoon, Miso; Kim, Jeongjun; Hong, Yeonhee; Lee, Hee Suk; Park, Eun Kyu; Hahm, Jong Cheon; Kim, Jin Woo; Shin, Soon Shik; Kim, Min-Young; Yoon, Michung

2015-01-01

It has been suggested that angiogenesis modulates adipogenesis and obesity. This study was undertaken to determine whether ALS-L1023 (ALS) prepared by a two-step organic solvent fractionation from Melissa leaves, which exhibits antiangiogenic activity, can regulate adipose tissue growth. The effects of ALS on angiogenesis and extracellular matrix remodeling were measured using in vitro assays. The effects of ALS on adipose tissue growth were investigated in high fat diet-induced obese mice. ALS inhibited VEGF- and bFGF-induced endothelial cell proliferation and suppressed matrix metalloproteinase (MMP) activity in vitro. Compared to obese control mice, administration of ALS to obese mice reduced body weight gain, adipose tissue mass and adipocyte size without affecting appetite. ALS treatment decreased blood vessel density and MMP activity in adipose tissues. ALS reduced the mRNA levels of angiogenic factors (VEGF-A and FGF-2) and MMPs (MMP-2 and MMP-9), whereas ALS increased the mRNA levels of angiogenic inhibitors (TSP-1, TIMP-1, and TIMP-2) in adipose tissues. The protein levels of VEGF, MMP-2 and MMP-9 were also decreased by ALS in adipose tissue. Metabolic changes in plasma lipids, liver triglycerides, and hepatic expression of fatty acid oxidation genes occurred during ALS-induced weight loss. These results suggest that ALS, which has antiangiogenic and MMP inhibitory activities, reduces adipose tissue mass in nutritionally obese mice, demonstrating that adipose tissue growth can be regulated by angiogenesis inhibitors. PMID:26599360

Epigenetic regulation of depot-specific gene expression in adipose tissue.

PubMed

Gehrke, Sandra; Brueckner, Bodo; Schepky, Andreas; Klein, Johannes; Iwen, Alexander; Bosch, Thomas C G; Wenck, Horst; Winnefeld, Marc; Hagemann, Sabine

2013-01-01

In humans, adipose tissue is distributed in subcutaneous abdominal and subcutaneous gluteal depots that comprise a variety of functional differences. Whereas energy storage in gluteal adipose tissue has been shown to mediate a protective effect, an increase of abdominal adipose tissue is associated with metabolic disorders. However, the molecular basis of depot-specific characteristics is not completely understood yet. Using array-based analyses of transcription profiles, we identified a specific set of genes that was differentially expressed between subcutaneous abdominal and gluteal adipose tissue. To investigate the role of epigenetic regulation in depot-specific gene expression, we additionally analyzed genome-wide DNA methylation patterns in abdominal and gluteal depots. By combining both data sets, we identified a highly significant set of depot-specifically expressed genes that appear to be epigenetically regulated. Interestingly, the majority of these genes form part of the homeobox gene family. Moreover, genes involved in fatty acid metabolism were also differentially expressed. Therefore we suppose that changes in gene expression profiles might account for depot-specific differences in lipid composition. Indeed, triglycerides and fatty acids of abdominal adipose tissue were more saturated compared to triglycerides and fatty acids in gluteal adipose tissue. Taken together, our results uncover clear differences between abdominal and gluteal adipose tissue on the gene expression and DNA methylation level as well as in fatty acid composition. Therefore, a detailed molecular characterization of adipose tissue depots will be essential to develop new treatment strategies for metabolic syndrome associated complications.

FABP4 dynamics in obesity: discrepancies in adipose tissue and liver expression regarding circulating plasma levels.

PubMed

Queipo-Ortuño, María Isabel; Escoté, Xavier; Ceperuelo-Mallafré, Victoria; Garrido-Sanchez, Lourdes; Miranda, Merce; Clemente-Postigo, Mercedes; Pérez-Pérez, Rafael; Peral, Belen; Cardona, Fernando; Fernández-Real, Jose Manuel; Tinahones, Francisco J; Vendrell, Joan

2012-01-01

FABP4 is predominantly expressed in adipose tissue, and its circulating levels are linked with obesity and a poor atherogenic profile. In patients with a wide BMI range, we analyze FABP4 expression in adipose and hepatic tissues in the settings of obesity and insulin resistance. Associations between FABP4 expression in adipose tissue and the FABP4 plasma level as well as the main adipogenic and lipolytic genes expressed in adipose tissue were also analyzed. The expression of several lipogenic, lipolytic, PPAR family and FABP family genes was analyzed by real time PCR. FABP4 protein expression in total adipose tissues and its fractions were determined by western blot. In obesity FABP4 expression was down-regulated (at both mRNA and protein levels), with its levels mainly predicted by ATGL and inversely by the HOMA-IR index. The BMI appeared as the only determinant of the FABP4 variation in both adipose tissue depots. FABP4 plasma levels showed a significant progressive increase according to BMI but no association was detected between FABP4 circulating levels and SAT or VAT FABP4 gene expression. The gene expression of FABP1, FABP4 and FABP5 in hepatic tissue was significantly higher in tissue from the obese IR patients compared to the non-IR group. The inverse pattern in FABP4 expression between adipose and hepatic tissue observed in morbid obese patients, regarding the IR context, suggests that both tissues may act in a balanced manner. These differences may help us to understand the discrepancies between circulating plasma levels and adipose tissue expression in obesity.

Pomegranate vinegar attenuates adiposity in obese rats through coordinated control of AMPK signaling in the liver and adipose tissue

PubMed Central

2013-01-01

Background The effect of pomegranate vinegar (PV) on adiposity was investigated in high-fat diet (HF)-induced obese rats. Methods The rats were divided into 5 groups and treated with HF with PV or acetic acid (0, 6.5 or 13% w/w) for 16 weeks. Statistical analyses were performed by the Statistical Analysis Systems package, version 9.2. Results Compared to control, PV supplementation increased phosphorylation of AMP-activated protein kinase (AMPK), leading to changes in mRNA expressions: increases for hormone sensitive lipase and mitochondrial uncoupling protein 2 and decreases for sterol regulatory element binding protein-1c (SREBP-1c) and peroxisome proliferator-activated receptorγ (PPARγ) in adipose tissue; increases for PPARα and carnitinepalmitoyltransferase-1a (CPT-1a) and decrease for SREBP-1c in the liver. Concomitantly, PV reduced increases of body weight (p = 0.048), fat mass (p = 0.033), hepatic triglycerides (p = 0.005), and plasma triglycerides (p = 0.001). Conclusions These results suggest that PV attenuates adiposity through the coordinated control of AMPK, which leads to promotion of lipolysis in adipose tissue and stimulation of fatty acid oxidation in the liver. PMID:24180378

Insulin action in adipose tissue and muscle in hypothyroidism.

PubMed

Dimitriadis, George; Mitrou, Panayota; Lambadiari, Vaia; Boutati, Eleni; Maratou, Eirini; Panagiotakos, Demosthenes B; Koukkou, Efi; Tzanela, Marinela; Thalassinos, Nikos; Raptis, Sotirios A

2006-12-01

Although insulin resistance in thyroid hormone excess is well documented, information on insulin action in hypothyroidism is limited. To investigate this, a meal was given to 11 hypothyroid (HO; aged 45 +/- 3 yr) and 10 euthyroid subjects (EU; aged 42 +/- 4 yr). Blood was withdrawn for 360 min from veins (V) draining the anterior abdominal sc adipose tissue and the forearm and from the radial artery (A). Blood flow (BF) in adipose tissue was measured with 133Xe and in forearm with strain-gauge plethysmography. Tissue glucose uptake was calculated as (A-V)glucose(BF), lipoprotein lipase as (A-V)Triglycerides(BF), and lipolysis as [(V-A)glycerol(BF)]-lipoprotein lipase. The HO group had higher glucose and insulin levels than the EU group (P < 0.05). In HO vs. EU after meal ingestion (area under curve 0-360 min): 1) BF (1290 +/- 79 vs. 1579 +/- 106 ml per 100 ml tissue in forearm and 706 +/- 105 vs. 1340 +/- 144 ml per 100 ml tissue in adipose tissue) and glucose uptake (464 +/- 74 vs. 850 +/- 155 micromol per 100 ml tissue in forearm and 208 +/- 42 vs. 406 +/- 47 micromol per 100 ml tissue in adipose tissue) were decreased (P < 0.05), but fractional glucose uptake was similar (28 +/- 6 vs. 33 +/- 6% per minute in forearm and 17 +/- 4 vs. 14 +/- 3% per minute in adipose tissue); 2) suppression of lipolysis by insulin was similar; and 3) plasma triglycerides were elevated (489 +/- 91 vs. 264 +/- 36 nmol/liter.min, P < 0.05), whereas adipose tissue lipoprotein lipase (42 +/- 11 vs. 80 +/- 21 micromol per 100 ml tissue) and triglyceride clearance (45 +/- 10 vs. 109 +/- 21 ml per 100 ml tissue) were decreased in HO (P < 0.05). In hypothyroidism: 1) glucose uptake in muscle and adipose tissue is resistant to insulin; 2) suppression of lipolysis by insulin is not impaired; and 3) hypertriglyceridemia is due to decreased clearance by the adipose tissue.

Evidence for the ectopic synthesis of melanin in human adipose tissue.

PubMed

Randhawa, Manpreet; Huff, Tom; Valencia, Julio C; Younossi, Zobair; Chandhoke, Vikas; Hearing, Vincent J; Baranova, Ancha

2009-03-01

Melanin is a common pigment in animals. In humans, melanin is produced in melanocytes, in retinal pigment epithelium (RPE) cells, in the inner ear, and in the central nervous system. Previously, we noted that human adipose tissue expresses several melanogenesis-related genes. In the current study, we confirmed the expression of melanogenesis-related mRNAs and proteins in human adipose tissue using real-time polymerase chain reaction and immunohistochemical staining. TYR mRNA signals were also detected by in situ hybridization in visceral adipocytes. The presence of melanin in human adipose tissue was revealed both by Fontana-Masson staining and by permanganate degradation of melanin coupled with liquid chromatography/ultraviolet/mass spectrometry determination of the pyrrole-2,3,5-tricarboxylic acid (PTCA) derivative of melanin. We also compared melanogenic activities in adipose tissues and in other human tissues using the L-[U-(14)C] tyrosine assay. A marked heterogeneity in the melanogenic activities of individual adipose tissue extracts was noted. We hypothesize that the ectopic synthesis of melanin in obese adipose may serve as a compensatory mechanism that uses its anti-inflammatory and its oxidative damage-absorbing properties. In conclusion, our study demonstrates for the first time that the melanin biosynthesis pathway is functional in adipose tissue.

Effects of exercise training on chronic inflammation in obesity : current evidence and potential mechanisms.

PubMed

You, Tongjian; Arsenis, Nicole C; Disanzo, Beth L; Lamonte, Michael J

2013-04-01

Chronic, systemic inflammation is an independent risk factor for several major clinical diseases. In obesity, circulating levels of inflammatory markers are elevated, possibly due to increased production of pro-inflammatory cytokines from several tissues/cells, including macrophages within adipose tissue, vascular endothelial cells and peripheral blood mononuclear cells. Recent evidence supports that adipose tissue hypoxia may be an important mechanism through which enlarged adipose tissue elicits local tissue inflammation and further contributes to systemic inflammation. Current evidence supports that exercise training, such as aerobic and resistance exercise, reduces chronic inflammation, especially in obese individuals with high levels of inflammatory biomarkers undergoing a longer-term intervention. Several studies have reported that this effect is independent of the exercise-induced weight loss. There are several mechanisms through which exercise training reduces chronic inflammation, including its effect on muscle tissue to generate muscle-derived, anti-inflammatory 'myokine', its effect on adipose tissue to improve hypoxia and reduce local adipose tissue inflammation, its effect on endothelial cells to reduce leukocyte adhesion and cytokine production systemically, and its effect on the immune system to lower the number of pro-inflammatory cells and reduce pro-inflammatory cytokine production per cell. Of these potential mechanisms, the effect of exercise training on adipose tissue oxygenation is worth further investigation, as it is very likely that exercise training stimulates adipose tissue angiogenesis and increases blood flow, thereby reducing hypoxia and the associated chronic inflammation in adipose tissue of obese individuals.

Adipose-Derived Stem Cell Delivery for Adipose Tissue Engineering: Current Status and Potential Applications in a Tissue Engineering Chamber Model.

PubMed

Zhan, Weiqing; Tan, Shaun S; Lu, Feng

2016-08-01

In reconstructive surgery, there is a clinical need for adequate implants to repair soft tissue defects caused by traumatic injury, tumor resection, or congenital abnormalities. Adipose tissue engineering may provide answers to this increasing demand. This study comprehensively reviews current approaches to adipose tissue engineering, detailing different cell carriers under investigation, with a special focus on the application of adipose-derived stem cells (ASCs). ASCs act as building blocks for new tissue growth and as modulators of the host response. Recent studies have also demonstrated that the implantation of a hollow protected chamber, combined with a vascular pedicle within the fat flaps provides blood supply and enables the growth of large-volume of engineered soft tissue. Conceptually, it would be of value to co-regulate this unique chamber model with adipose-derived stem cells to obtain a greater volume of soft tissue constructs for clinical use. Our review provides a cogent update on these advances and details the generation of possible fat substitutes.

Human adipose-derived stem cells: definition, isolation, tissue-engineering applications.

PubMed

Nae, S; Bordeianu, I; Stăncioiu, A T; Antohi, N

2013-01-01

Recent researches have demonstrated that the most effective repair system of the body is represented by stem cells - unspecialized cells, capable of self-renewal through successive mitoses, which have also the ability to transform into different cell types through differentiation. The discovery of adult stem cells represented an important step in regenerative medicine because they no longer raises ethical or legal issues and are more accessible. Only in 2002, stem cells isolated from adipose tissue were described as multipotent stem cells. Adipose tissue stem cells benefits in tissue engineering and regenerative medicine are numerous. Development of adipose tissue engineering techniques offers a great potential in surpassing the existing limits faced by the classical approaches used in plastic and reconstructive surgery. Adipose tissue engineering clinical applications are wide and varied, including reconstructive, corrective and cosmetic procedures. Nowadays, adipose tissue engineering is a fast developing field, both in terms of fundamental researches and medical applications, addressing issues related to current clinical pathology or trauma management of soft tissue injuries in different body locations.

Plasticity of adipose tissue in response to fasting and refeeding in male mice.

PubMed

Tang, Hao-Neng; Tang, Chen-Yi; Man, Xiao-Fei; Tan, Shu-Wen; Guo, Yue; Tang, Jun; Zhou, Ci-La; Zhou, Hou-De

2017-01-01

Fasting is the most widely prescribed and self-imposed strategy for treating excessive weight gain and obesity, and has been shown to exert a number of beneficial effects. The aim of the present study was to determine the exact role of fasting and subsequent refeeding on fat distribution in mice. C57/BL6 mice fasted for 24 to 72 h and were then subjected to refeeding for 72 h. At 24, 48 and 72 h of fasting, and 12, 24, 48 and 72 h of refeeding, the mice were sacrificed, and serum and various adipose tissues were collected. Serum biochemical parameters, adipose tissue masses and histomorphological analysis of different depots were detected. MRNA was isolated from various adipose tissues, and the expressions of thermogenesis, visceral signature and lipid metabolism-related genes were examined. The phenotypes of adipose tissues between juvenile and adult mice subjected to fasting and refeeding were also compared. Fasting preferentially consumed mesenteric fat mass and decreased the cell size of mesenteric depots; however, refeeding recovered the mass and morphology of inguinal adipose tissues preferentially compared with visceral depots. Thermogenesis-related gene expression in the inguinal WAT and interscapular BAT were suppressed. Mitochondrial biogenesis was affected by fasting in a depot-specific manner. Furthermore, a short period of fasting led to an increase in visceral signature genes ( Wt1, Tcf21 ) in subcutaneous adipose tissue, while the expression of these genes decreased sharply as the fasting time increased. Additionally, lipogenesis-related markers were enhanced to a greater extent greater in subcutaneous depots compared with those in visceral adipose tissues by refeeding. Although similar phenotypic changes in adipose tissue were observed between juvenile mice and adult mice subjected to fasting and refeeding, the alterations appeared earlier and more sensitively in juvenile mice. Fasting preferentially consumes lipids in visceral adipose tissues, whereas refeeding recovers lipids predominantly in subcutaneous adipose tissues, which indicated the significance of plasticity of adipose organs for fat distribution when subject to food deprivation or refeeding.

Mechanical Stimulation of Adipose-Derived Stem Cells for Functional Tissue Engineering of the Musculoskeletal System via Cyclic Hydrostatic Pressure, Simulated Microgravity, and Cyclic Tensile Strain.

PubMed

Nordberg, Rachel C; Bodle, Josie C; Loboa, Elizabeth G

2018-01-01

It is critical that human adipose stem cell (hASC) tissue-engineering therapies possess appropriate mechanical properties in order to restore function of the load bearing tissues of the musculoskeletal system. In an effort to elucidate the hASC response to mechanical stimulation and develop mechanically robust tissue engineered constructs, recent research has utilized a variety of mechanical loading paradigms including cyclic tensile strain, cyclic hydrostatic pressure, and mechanical unloading in simulated microgravity. This chapter describes methods for applying these mechanical stimuli to hASC to direct differentiation for functional tissue engineering of the musculoskeletal system.

Transcriptome profiling of visceral adipose tissue in a novel obese rat model, WNIN/Ob & its comparison with other animal models.

PubMed

Sakamuri, Siva Sankara Vara Prasad; Putcha, Uday Kumar; Veettil, Giridharan Nappan; Ayyalasomayajula, Vajreswari

2016-09-01

Adipose tissue dysfunction in obesity is linked to the development of type 2 diabetes and cardiovascular diseases. We studied the differential gene expression in retroperitoneal adipose tissue of a novel obese rat model, WNIN/Ob, to understand the possible underlying transcriptional changes involved in the development of obesity and associatedcomorbidities in this model. Four month old, male WNIN/Ob lean and obese rats were taken, blood was collected and tissues were dissected. Body composition analysis and adipose tissue histology were performed. Global gene expression in retroperitoneal adipose tissue of lean and obese rats was studied by microarray using Affymetrix GeneChips. One thousand and seventeen probe sets were downregulated and 963 probe sets were upregulated (more than two-fold) in adipose tissue of WNIN/Ob obese rats when compared to that of lean rats. Small nucleolar RNA (SnoRNA) made most of the underexpressed probe sets, whereas immune system-related genes werethe most overexpressed in the adipose tissues of obese rats. Genes coding for cytoskeletal proteinswere downregulated, whereas genes related to lipid biosynthesis were elevated in the adipose tissue of obese rats. Majority of the altered genes and pathways in adipose tissue of WNIN/Ob obese rats were similar to the observations in other obese animal models and human obesity. Based on these observations, it is proposed that WNIN/Ob obese rat model may be a good model to study the mechanisms involved in the development of obesity and its comorbidities. Downregulation of SnoRNA appears to be a novel feature in this obese rat model.

Modal response of a computational vocal fold model with a substrate layer of adipose tissue.

PubMed

Jones, Cameron L; Achuthan, Ajit; Erath, Byron D

2015-02-01

This study demonstrates the effect of a substrate layer of adipose tissue on the modal response of the vocal folds, and hence, on the mechanics of voice production. Modal analysis is performed on the vocal fold structure with a lateral layer of adipose tissue. A finite element model is employed, and the first six mode shapes and modal frequencies are studied. The results show significant changes in modal frequencies and substantial variation in mode shapes depending on the strain rate of the adipose tissue. These findings highlight the importance of considering adipose tissue in computational vocal fold modeling.

Validation of Anthropometric Indices of Adiposity against Whole-Body Magnetic Resonance Imaging – A Study within the German European Prospective Investigation into Cancer and Nutrition (EPIC) Cohorts

PubMed Central

Neamat-Allah, Jasmine; Wald, Diana; Hüsing, Anika; Teucher, Birgit; Wendt, Andrea; Delorme, Stefan; Dinkel, Julien; Vigl, Matthaeus; Bergmann, Manuela M.; Feller, Silke; Hierholzer, Johannes; Boeing, Heiner; Kaaks, Rudolf

2014-01-01

Background In epidemiological studies, measures of body fat generally are obtained through anthropometric indices such as the body mass index (BMI), waist (WC), and hip circumferences (HC). Such indices, however, can only provide estimates of a person’s true body fat content, overall or by adipose compartment, and may have limited accuracy, especially for the visceral adipose compartment (VAT). Objective To determine the extent to which different body adipose tissue compartments are adequately predicted by anthropometry, and to identify anthropometric measures alone, or in combination to predict overall adiposity and specific adipose tissue compartments, independently of age and body size (height). Methods In a sub-study of 1,192 participants of the German EPIC (European Prospective Investigation into Cancer and Nutrition) cohorts, whole-body MRI was performed to determine adipose and muscle tissue compartments. Additional anthropometric measurements of BMI, WC and HC were taken. Results After adjusting for age and height, BMI, WC and HC were better predictors of total body volume (TBV), total adipose tissue (TAT) and subcutaneous adipose tissue (SAT) than for VAT, coronary adipose tissue (CAT) and skeletal muscle tissue (SMT). In both sexes, BMI was the best predictor for TBV (men: r = 0.72 [0.68–0.76], women: r = 0.80 [0.77–0.83]) and SMT (men: r = 0.52 [0.45–0.57], women: r = 0.48 [0.41–0.54]). WC was the best predictor variable for TAT (r = 0.48 [0.41–0.54]), VAT (r = 0.44 [0.37–0.50]) and CAT (r = 0.34 [0.26–0.41]) (men), and for VAT (r = 0.42 [0.35–0.49]) and CAT (r = 0.29 [0.22–0.37]) (women). BMI was the best predictor for TAT (r = 0.49 [0.43–0.55]) (women). HC was the best predictor for SAT (men (r = 0.39 [0.32–0.45]) and women (r = 0.52 [0.46–0.58])). Conclusions Especially the volumes of internal body fat compartments are poorly predicted by anthropometry. A possible implication may be that associations of chronic disease risks with the sizes of internal body fat as measured by BMI, WC and HC may be strongly underestimated. PMID:24626110

MKK6 controls T3-mediated browning of white adipose tissue.

PubMed

Matesanz, Nuria; Bernardo, Edgar; Acín-Pérez, Rebeca; Manieri, Elisa; Pérez-Sieira, Sonia; Hernández-Cosido, Lourdes; Montalvo-Romeral, Valle; Mora, Alfonso; Rodríguez, Elena; Leiva-Vega, Luis; Lechuga-Vieco, Ana Victoria; Ruiz-Cabello, Jesús; Torres, Jorge L; Crespo-Ruiz, Maria; Centeno, Francisco; Álvarez, Clara V; Marcos, Miguel; Enríquez, Jose Antonio; Nogueiras, Ruben; Sabio, Guadalupe

2017-10-11

Increasing the thermogenic capacity of adipose tissue to enhance organismal energy expenditure is considered a promising therapeutic strategy to combat obesity. Here, we report that expression of the p38 MAPK activator MKK6 is elevated in white adipose tissue of obese individuals. Using knockout animals and shRNA, we show that Mkk6 deletion increases energy expenditure and thermogenic capacity of white adipose tissue, protecting mice against diet-induced obesity and the development of diabetes. Deletion of Mkk6 increases T3-stimulated UCP1 expression in adipocytes, thereby increasing their thermogenic capacity. Mechanistically, we demonstrate that, in white adipose tissue, p38 is activated by an alternative pathway involving AMPK, TAK, and TAB. Our results identify MKK6 in adipocytes as a potential therapeutic target to reduce obesity.Brown and beige adipose tissues dissipate heat via uncoupling protein 1 (UCP1). Here the authors show that the stress activated kinase MKK6 acts as a repressor of UCP1 expression, suggesting that its inhibition promotes adipose tissue browning and increases organismal energy expenditure.

Optimizing Adipose Tissue Extract Isolation with Stirred Suspension Culture.

PubMed

Zhang, Yan; Yu, Mei; Zhao, Xueyong; Dai, Minjia; Chen, Chang; Tian, Weidong

2018-05-31

Adherent culture which is used to collect adipose tissue extract (ATE) previously brings the problem of inhomogeneity and non-repeatability. Here we aim to extract ATE with stirred suspension culture to speed up the extraction process, stabilize the yield and improve consistent potency metrics of ATE. ATE was collected with adherent culture (ATE-A) and stirred suspension culture (ATE-S) separately. Protein yield and composition were detected by SDS-PAGE while cytokines in ATE were determined with ELISA. The adipogenic and angiogenic potential of ATE were compared by Western blot and qPCR. In addition, HE staining and LDH activity assays were used to analyze the cell viability of adipose tissue cultured with different methods. The yield of ATE-S was consistent while ATE-A varied notably. Characterization of the protein composition and exosome-like vesicles (ELVs) indicated no significant difference between ATE-S and ATE-A. The concentrations of cytokines (VEGF, bFGF and IL-6) showed no significant difference while IGF in ATE-S was higher than that in ATE-A. ATE-S showed upregulated adipogenic and angiogenic potential compared to ATE-A. Morever, stirred suspension culture decreased the LDH activity of ATE while increased the number of viable adipocytes and reduced adipose tissue necrosis. Compared with adherent culture, stirred suspension culture is a reliable, time and labor-saving method to collect ATE, which might be used to improve the downstream applications of ATE.

Improvement of adipose tissue-derived cells by low-energy extracorporeal shock wave therapy.

PubMed

Priglinger, Eleni; Schuh, Christina M A P; Steffenhagen, Carolin; Wurzer, Christoph; Maier, Julia; Nuernberger, Sylvia; Holnthoner, Wolfgang; Fuchs, Christiane; Suessner, Susanne; Rünzler, Dominik; Redl, Heinz; Wolbank, Susanne

2017-09-01

Cell-based therapies with autologous adipose tissue-derived cells have shown great potential in several clinical studies in the last decades. The majority of these studies have been using the stromal vascular fraction (SVF), a heterogeneous mixture of fibroblasts, lymphocytes, monocytes/macrophages, endothelial cells, endothelial progenitor cells, pericytes and adipose-derived stromal/stem cells (ASC) among others. Although possible clinical applications of autologous adipose tissue-derived cells are manifold, they are limited by insufficient uniformity in cell identity and regenerative potency. In our experimental set-up, low-energy extracorporeal shock wave therapy (ESWT) was performed on freshly obtained human adipose tissue and isolated adipose tissue SVF cells aiming to equalize and enhance stem cell properties and functionality. After ESWT on adipose tissue we could achieve higher cellular adenosine triphosphate (ATP) levels compared with ESWT on the isolated SVF as well as the control. ESWT on adipose tissue resulted in a significantly higher expression of single mesenchymal and vascular marker compared with untreated control. Analysis of SVF protein secretome revealed a significant enhancement in insulin-like growth factor (IGF)-1 and placental growth factor (PLGF) after ESWT on adipose tissue. Summarizing we could show that ESWT on adipose tissue enhanced the cellular ATP content and modified the expression of single mesenchymal and vascular marker, and thus potentially provides a more regenerative cell population. Because the effectiveness of autologous cell therapy is dependent on the therapeutic potency of the patient's cells, this technology might raise the number of patients eligible for autologous cell transplantation. Copyright © 2017 International Society for Cellular Therapy. Published by Elsevier Inc. All rights reserved.

Role of A1 and A2A adenosine receptor agonists in adipose tissue inflammation induced by obesity in mice.

PubMed

DeOliveira, Caroline Candida; Paiva Caria, Cintia Rabelo E; Ferreira Gotardo, Erica Martins; Ribeiro, Marcelo Lima; Gambero, Alessandra

2017-03-15

Adenosine receptors are expressed in adipose tissue and control physiological and pathological events such as lipolysis and inflammation. The aim of this study was to evaluate the activity of N 6 -cyclopentyladenosine (CPA), a potent and selective A 1 adenosine receptor agonist; 2-p-(2-carboxyethyl)phenethylamino-5'-N-ethylcarboxyamidoadenosine hydrochloride (CGS-21680), an A 2A adenosine receptor agonist; and 5'-N-ethylcarboxamidoadenosine (NECA), a potent non-selective adenosine receptor agonist on adipose tissue inflammatory alterations induced by obesity in mice. Swiss mice were fed with a high-fat diet for 12 weeks and agonists were administered in the last two weeks. Body weight, adiposity and glucose homeostasis were evaluated. Inflammation in adipose tissue was assessed by evaluation of adipokine production and macrophage infiltration. Adenosine receptor signaling in adipose tissue was also evaluated. Mice that received CGS21680 presented an improvement in glucose homeostasis in association with systemically reduced inflammatory markers (TNF-α, PAI-1) and in the visceral adipose tissue (TNF-α, MCP-1, macrophage infiltration). Activation of p38 signaling was found in adipose tissue of this group of mice. NECA-treated mice presented some improvements in glucose homeostasis associated with an observed weight loss. Mice that received CPA presented only a reduction in the ex vivo basal lipolysis rate measured within visceral adipose tissue. In conclusion, administration of the A 2A receptor agonist to obese mice resulted in improvements in glucose homeostasis and adipose tissue inflammation, corroborating the idea that new therapeutics to treat obesity could emerge from these compounds. Copyright © 2017 Elsevier B.V. All rights reserved.

Chronic hindlimb suspension unloading markedly decreases turnover rates of skeletal and cardiac muscle proteins and adipose tissue triglycerides.

PubMed

Bederman, Ilya R; Lai, Nicola; Shuster, Jeffrey; Henderson, Leigh; Ewart, Steven; Cabrera, Marco E

2015-07-01

We previously showed that a single bolus of "doubly-labeled" water ((2)H2 (18)O) can be used to simultaneously determine energy expenditure and turnover rates (synthesis and degradation) of tissue-specific lipids and proteins by modeling labeling patterns of protein-bound alanine and triglyceride-bound glycerol (Bederman IR, Dufner DA, Alexander JC, Previs SF. Am J Physiol Endocrinol Metab 290: E1048-E1056, 2006). Using this novel method, we quantified changes in the whole body and tissue-specific energy balance in a rat model of simulated "microgravity" induced by hindlimb suspension unloading (HSU). After chronic HSU (3 wk), rats exhibited marked atrophy of skeletal and cardiac muscles and significant decrease in adipose tissue mass. For example, soleus muscle mass progressively decreased 11, 43, and 52%. We found similar energy expenditure between control (90 ± 3 kcal · kg(-1)· day(-1)) and hindlimb suspended (81 ± 6 kcal/kg day) animals. By comparing food intake (∼ 112 kcal · kg(-1) · day(-1)) and expenditure, we found that animals maintained positive calorie balance proportional to their body weight. From multicompartmental fitting of (2)H-labeling patterns, we found significantly (P < 0.005) decreased rates of synthesis (percent decrease from control: cardiac, 25.5%; soleus, 70.3%; extensor digitorum longus, 44.9%; gastrocnemius, 52.5%; and adipose tissue, 39.5%) and rates of degradation (muscles: cardiac, 9.7%; soleus, 52.0%; extensor digitorum longus, 27.8%; gastrocnemius, 37.4%; and adipose tissue, 50.2%). Overall, HSU affected growth of young rats by decreasing the turnover rates of proteins in skeletal and cardiac muscles and adipose tissue triglycerides. Specifically, we found that synthesis rates of skeletal and cardiac muscle proteins were affected to a much greater degree compared with the decrease in degradation rates, resulting in large negative balance and significant tissue loss. In contrast, we found a small decrease in adipose tissue triglyceride synthesis paired with a large decrease in degradation, resulting in smaller negative energy balance and loss of fat mass. We conclude that HSU in rats differentially affects turnover of muscle proteins vs. adipose tissue triglycerides. Copyright © 2015 the American Physiological Society.

Flow cytometry on the stromal-vascular fraction of white adipose tissue.

PubMed

Brake, Danett K; Smith, C Wayne

2008-01-01

Adipose tissue contains cell types other than adipocytes that may contribute to complications linked to obesity. For example, macrophages have been shown to infiltrate adipose tissue in response to a high-fat diet. Isolation of the stromal-vascular fraction of adipose tissue allows one to use flow cytometry to analyze cell surface markers on leukocytes. Here, we present a technical approach to identify subsets of leukocytes that differentially express cell surface markers.

Uric Acid Secretion from Adipose Tissue and Its Increase in Obesity*

PubMed Central

Tsushima, Yu; Nishizawa, Hitoshi; Tochino, Yoshihiro; Nakatsuji, Hideaki; Sekimoto, Ryohei; Nagao, Hirofumi; Shirakura, Takashi; Kato, Kenta; Imaizumi, Keiichiro; Takahashi, Hiroyuki; Tamura, Mizuho; Maeda, Norikazu; Funahashi, Tohru; Shimomura, Iichiro

2013-01-01

Obesity is often accompanied by hyperuricemia. However, purine metabolism in various tissues, especially regarding uric acid production, has not been fully elucidated. Here we report, using mouse models, that adipose tissue could produce and secrete uric acid through xanthine oxidoreductase (XOR) and that the production was enhanced in obesity. Plasma uric acid was elevated in obese mice and attenuated by administration of the XOR inhibitor febuxostat. Adipose tissue was one of major organs that had abundant expression and activities of XOR, and adipose tissues in obese mice had higher XOR activities than those in control mice. 3T3-L1 and mouse primary mature adipocytes produced and secreted uric acid into culture medium. The secretion was inhibited by febuxostat in a dose-dependent manner or by gene knockdown of XOR. Surgical ischemia in adipose tissue increased local uric acid production and secretion via XOR, with a subsequent increase in circulating uric acid levels. Uric acid secretion from whole adipose tissue was increased in obese mice, and uric acid secretion from 3T3-L1 adipocytes was increased under hypoxia. Our results suggest that purine catabolism in adipose tissue could be enhanced in obesity. PMID:23913681

Physiological Aging: Links Among Adipose Tissue Dysfunction, Diabetes, and Frailty.

PubMed

Stout, Michael B; Justice, Jamie N; Nicklas, Barbara J; Kirkland, James L

2017-01-01

Advancing age is associated with progressive declines in physiological function that lead to overt chronic disease, frailty, and eventual mortality. Importantly, age-related physiological changes occur in cellularity, insulin-responsiveness, secretory profiles, and inflammatory status of adipose tissue, leading to adipose tissue dysfunction. Although the mechanisms underlying adipose tissue dysfunction are multifactorial, the consequences result in secretion of proinflammatory cytokines and chemokines, immune cell infiltration, an accumulation of senescent cells, and an increase in senescence-associated secretory phenotype (SASP). These processes synergistically promote chronic sterile inflammation, insulin resistance, and lipid redistribution away from subcutaneous adipose tissue. Without intervention, these effects contribute to age-related systemic metabolic dysfunction, physical limitations, and frailty. Thus adipose tissue dysfunction may be a fundamental contributor to the elevated risk of chronic disease, disability, and adverse health outcomes with advancing age. ©2017 Int. Union Physiol. Sci./Am. Physiol. Soc.

Seasonal heat stress affects adipose tissue proteome toward enrichment of the Nrf2-mediated oxidative stress response in late-pregnant dairy cows.

PubMed

Zachut, M; Kra, G; Livshitz, L; Portnick, Y; Yakoby, S; Friedlander, G; Levin, Y

2017-03-31

Environmental heat stress and metabolic stress during transition from late gestation to lactation are main factors limiting production in dairy cattle, and there is a complex interaction between them. Many proteins expressed in adipose tissue are involved in metabolic responses to stress. We aimed to investigate the effects of seasonal heat stress on adipose proteome in late-pregnant cows, and to identify biomarkers of heat stress. Late pregnant cows during summer heat stress (S, n=18), or during the winter season (W, n=12) were used. Subcutaneous adipose tissue biopsies sampled 14days prepartum from S (n=10) and W (n=8) were analyzed by intensity-based, label-free, quantitative shotgun proteomics (nano-LC-MS/MS). Plasma concentrations of malondialdehyde and cortisol were higher in S than in W cows. Proteomic analysis revealed that 107/1495 proteins were differentially abundant in S compared to W (P<0.05 and fold change of at least ±1.5). Top canonical pathways in S vs. W adipose were Nrf2-mediated oxidative stress response, acute-phase response, and FXR/RXR and LXR/RXR activation. Novel biomarkers of heat stress in adipose tissue were found. These findings indicate that seasonal heat stress has a unique effect on adipose tissue in late-pregnant cows. This work shows that seasonal heat stress increases plasma concentrations of the oxidative stress marker malondialdehyde and cortisol in transition dairy cows. As many proteins expressed in the adipose tissue are involved in metabolic responses to stress, we investigated the effects of heat stress on the proteome of adipose tissue from late-pregnant cows during summer or winter seasons. We demonstrated that heat stress enriches several stress-related pathways, such as the Nrf2-mediated oxidative stress response and the acute-phase response in adipose tissues. Thus, environmental heat stress has a unique effect on adipose tissue in late-pregnant cows, as part of the regulatory adaptations to chronic heat load during the summer season. In addition, this study presents the widest available dataset of adipose tissue proteome in dairy cows, and revealed several novel biomarkers of heat stress in adipose tissue of dairy cows, the use of which awaits further validation. Copyright © 2017 Elsevier B.V. All rights reserved.

From the Cover: Adipose tissue mass can be regulated through the vasculature

NASA Astrophysics Data System (ADS)

Rupnick, Maria A.; Panigrahy, Dipak; Zhang, Chen-Yu; Dallabrida, Susan M.; Lowell, Bradford B.; Langer, Robert; Judah Folkman, M.

2002-08-01

Tumor growth is angiogenesis dependent. We hypothesized that nonneoplastic tissue growth also depends on neovascularization. We chose adipose tissue as an experimental system because of its remodeling capacity. Mice from different obesity models received anti-angiogenic agents. Treatment resulted in dose-dependent, reversible weight reduction and adipose tissue loss. Marked vascular remodeling was evident in adipose tissue sections, which revealed decreased endothelial proliferation and increased apoptosis in treated mice compared with controls. Continuous treatment maintained mice near normal body weights for age without adverse effects. Metabolic adaptations in food intake, metabolic rate, and energy substrate utilization were associated with anti-angiogenic weight loss. We conclude that adipose tissue mass is sensitive to angiogenesis inhibitors and can be regulated by its vasculature.

Implication of low level inflammation in the insulin resistance of adipose tissue at late pregnancy.

PubMed

de Castro, J; Sevillano, J; Marciniak, J; Rodriguez, R; González-Martín, C; Viana, M; Eun-suk, O H; de Mouzon, S Hauguel; Herrera, E; Ramos, M P

2011-11-01

Insulin resistance is a characteristic of late pregnancy, and adipose tissue is one of the tissues that most actively contributes to the reduced maternal insulin sensitivity. There is evidence that pregnancy is a condition of moderate inflammation, although the physiological role of this low-grade inflammation remains unclear. The present study was designed to validate whether low-grade inflammation plays a role in the development of insulin resistance in adipose tissue during late pregnancy. To this end, we analyzed proinflammatory adipokines and kinases in lumbar adipose tissue of nonpregnant and late pregnant rats at d 18 and 20 of gestation. We found that circulating and tissue levels of adipokines, such as IL-1β, plasminogen activator inhibitor-1, and TNF-α, were increased at late pregnancy, which correlated with insulin resistance. The observed increase in adipokines coincided with an enhanced activation of p38 MAPK in adipose tissue. Treatment of pregnant rats with the p38 MAPK inhibitor SB 202190 increased insulin-stimulated tyrosine phosphorylation of the insulin receptor (IR) and IR substrate-1 in adipose tissue, which was paralleled by a reduction of IR substrate-1 serine phosphorylation and an enhancement of the metabolic actions of insulin. These results indicate that activation of p38 MAPK in adipose tissue contributes to adipose tissue insulin resistance at late pregnancy. Furthermore, the results of the present study support the hypothesis that physiological low-grade inflammation in the maternal organism is relevant to the development of pregnancy-associated insulin resistance.

Visceral adiposity index as an indicator of cardiometabolic risk in patients treated for craniopharyngioma.

PubMed

Ferraù, Francesco; Spagnolo, Federica; Cotta, Oana Ruxandra; Cannavò, Laura; Alibrandi, Angela; Russo, Giuseppina Tiziana; Aversa, Tommaso; Trimarchi, Francesco; Cannavò, Salvatore

2017-11-01

Craniopharyngioma is associated with metabolic alterations leading to increased cardiovascular mortality. Recently, the visceral adiposity index has been proposed as a marker of visceral adipose tissue dysfunction and of the related cardiometabolic risk. The role of the visceral adiposity index has never been explored in craniopharyngioma patients. We assessed the cardiometabolic risk on the basis of the visceral adiposity index in craniopharyngioma patients. We evaluated data of 24 patients treated for craniopharyngioma in a single-centre. We investigated the relationship among patients' clinical and biochemical features, cardiovascular risk -assessed by the Framingham and the atherosclerotic cardiovascular disease risk scores-, visceral adiposity index and adipose tissue dysfunction severity. Increased visceral adiposity index was found in 8 patients (33%). Adipose tissue dysfunction resulted to be severe, moderate or mild in 5, 2 and 1 cases. Increased visceral adiposity index significantly correlated with the occurrence of metabolic syndrome (p 0.027), IRI (p 0.001), triglycerides (p < 0.001), HOMA-IR (p < 0.001) and with lower ISI-Matsuda (p 0.005) and HDL-cholesterol (p < 0.001). Higher degree of adipose tissue dysfunction associated with increased insulin resistance. No gender difference was found for visceral adiposity index, adipose tissue dysfunction severity, and cardiovascular risk scores. Patients with adulthood onset craniopharyngioma showed higher Framingham risk score (p 0.004), atherosclerotic cardiovascular disease 10-year (p < 0.001) and lifetime (p 0.018) risk scores than those with childhood onset disease. Visceral adiposity index is increased in one third of our patients with craniopharyngioma, even if metabolic syndrome does not occur. Increased visceral adiposity index and adipose tissue dysfunction severity correlate with insulin sensitivity parameters, do not correlate with Framingham or atherosclerotic cardiovascular disease risk scores, and are not influenced by gender and age of disease onset.

Catalpol ameliorates high-fat diet-induced insulin resistance and adipose tissue inflammation by suppressing the JNK and NF-κB pathways

DOE Office of Scientific and Technical Information (OSTI.GOV)

Zhou, Jun, E-mail: hustzhj@hust.edu.cn; Xu, Gang; Ma, Shuai

Catalpol, a bioactive component from the root of Rehmannia glutinosa, has been shown to possess hypoglycemic effects in type 2 diabetic animal models, however, the underlying mechanisms remain poorly understood. Here we investigated the effect of catalpol on high-fat diet (HFD)-induced insulin resistance and adipose tissue inflammation in mice. Oral administration of catalpol at 100 mg/kg for 4 weeks had no effect on body weight of HFD-induced obese mice, but it significantly improved fasting glucose and insulin levels, glucose tolerance and insulin tolerance. Moreover, macrophage infiltration into adipose tissue was markedly reduced by catalpol. Intriguingly, catalpol also significantly reduced mRNA expressionsmore » of M1 pro-inflammatory cytokines, but increased M2 anti-inflammatory gene expressions in adipose tissue. Concurrently, catalpol significantly suppressed the c-Jun NH2-terminal kinase (JNK) and nuclear factor-kappa B (NF-κB) signaling pathways in adipose tissue. Collectively, these results suggest that catalpol may ameliorate HFD-induced insulin resistance in mice by attenuating adipose tissue inflammation and suppressing the JNK and NF-κB pathways, and thus provide important new insights into the underlying mechanisms of the antidiabetic effect of catalpol. - Highlights: • Catalpol ameliorates high-fat diet (HFD)-induced insulin resistance in mice. • Catalpol reduces adipose tissue macrophage infiltration in HFD-fed mice. • Catalpol regulates M1 and M2 inflammatory gene expression in obese adipose tissue. • Catalpol suppresses the JNK and NF-κB signaling pathways in obese adipose tissue.« less

Detrimental and protective fat: body fat distribution and its relation to metabolic disease.

PubMed

Booth, Andrea; Magnuson, Aaron; Foster, Michelle

2014-01-01

Obesity is linked to numerous comorbidities that include, but are not limited to, glucose intolerance, insulin resistance, dyslipidemia, and cardiovascular disease. Current evidence suggests, however, obesity itself is not an exclusive predictor of metabolic dysregulation but rather adipose tissue distribution. Obesity-related adverse health consequences occur predominately in individuals with upper body fat accumulation, the detrimental distribution, commonly associated with visceral obesity. Increased lower body subcutaneous adipose tissue, however, is associated with a reduced risk of obesity-induced metabolic dysregulation and even enhanced insulin sensitivity, thus, storage in this region is considered protective. The proposed mechanisms that causally relate the differential outcomes of adipose tissue distribution are often attributed to location and/or adipocyte regulation. Visceral adipose tissue effluent to the portal vein drains into the liver where hepatocytes are directly exposed to its metabolites and secretory products, whereas the subcutaneous adipose tissue drains systemically. Adipose depots are also inherently different in numerous ways such as adipokine release, immunity response and regulation, lipid turnover, rate of cell growth and death, and response to stress and sex hormones. Proximal extrinsic factors also play a role in the differential drive between adipose tissue depots. This review focuses on the deleterious mechanisms postulated to drive the differential metabolic response between central and lower body adipose tissue distribution.

Paradoxical Adipose Hyperplasia and Cellular Effects After Cryolipolysis: A Case Report.

PubMed

Seaman, Scott A; Tannan, Shruti C; Cao, Yiqi; Peirce, Shayn M; Gampper, Thomas J

2016-01-01

Cryolipolysis is a noninvasive technique for the reduction of subcutaneous adipose tissue by controlled, localized cooling, causing adipocyte apoptosis, reportedly without affecting surrounding tissue. Although cryolipolysis has a low incidence of adverse side effects 33 cases of paradoxical adipose hyperplasia (PAH) have been reported and the precise pathogenesis of PAH is poorly understood. This present case study of PAH aims to characterize the pathological changes in the adipose tissue of PAH on a cellular level by using multiple different assays [hematoxy lin and eosin staining, LIVE/DEAD staining, BODIPY(®) 558/568 C12 (4,4-Difluoro-5-(2-Thienyl)-4-Bora-3a,4a-Diaza-s-Indacene-3-dodecanoic acid) staining]. to identify the underlying mechanism of PAH and reduce the prevalence of PAH in the future. Tissue with PAH had fewer viable cells, significantly decreased quantities of interstitial cells (p = 0.04), and fewer vessels per adipose tissue area when compared to the control tissue. Adipocytes from the PAH tissue were on average slightly smaller than the control adipocytes. Adipocytes of PAH tissue had irregularly contoured edges when compared to the smooth, round edges of the control tissue. These findings from a neutral third party are contrary to prior reports from the inventors of this technique regarding effects of cryolipolysis on both the microvasculature and interstitial cells in adipose tissue. Our use of different assays to compare cryolipolysis-treated PAH tissue with untreated adipose tissue in the same patient showed adipose tissue that developed PAH was hypocellular and hypovascular. Contrary to prior reports from the inventors, cryolipolysis may cause vessel loss, which could lead to ischemia and/or hypoxia that further contributes to adipocyte death. LEVEL OF EVIDENCE 5: Risk. © 2015 The American Society for Aesthetic Plastic Surgery, Inc. Reprints and permission: journals.permissions@oup.com.

Maternal adipose tissue becomes a source of fatty acids for the fetus in fasted pregnant rats given diets with different fatty acid compositions.

PubMed

López-Soldado, Iliana; Ortega-Senovilla, Henar; Herrera, Emilio

2017-11-10

The utilization of long-chain polyunsaturated fatty acids (LCPUFA) by the fetus may exceed its capacity to synthesize them from essential fatty acids, so they have to come from the mother. Since adipose tissue lipolytic activity is greatly accelerated under fasting conditions during late pregnancy, the aim was to determine how 24 h fasting in late pregnant rats given diets with different fatty acid compositions affects maternal and fetal tissue fatty acid profiles. Pregnant Sprague-Dawley rats were given isoenergetic diets containing 10% palm-, sunflower-, olive- or fish-oil. Half the rats were fasted from day 19 of pregnancy and all were studied on day 20. Triacylglycerols (TAG), glycerol and non-esterified fatty acids (NEFA) were analyzed by enzymatic methods and fatty acid profiles were analyzed by gas chromatography. Fasting caused increments in maternal plasma NEFA, glycerol and TAG, indicating increased adipose tissue lipolytic activity. Maternal adipose fatty acid profiles paralleled the respective diets and, with the exception of animals on the olive oil diet, maternal fasting increased the plasma concentration of most fatty acids. This maintains the availability of LCPUFA to the fetus during brain development. The results show the major role played by maternal adipose tissue in the storage of dietary fatty acids during pregnancy, thus ensuring adequate availability of LCPUFA to the fetus during late pregnancy, even when food supply is restricted.

Correction of intermittent hypoxia reduces inflammation in obese subjects with obstructive sleep apnea

PubMed Central

Perrini, Sebastio; Quaranta, Vitaliano Nicola; Falcone, Vito Antonio; Kounaki, Stella; Ciavarella, Alessandro; Ficarella, Romina; Barbaro, Maria; Nigro, Pasquale; Carratù, Pierluigi; Natalicchio, Annalisa; Laviola, Luigi; Resta, Onofrio

2017-01-01

BACKGROUND. In obese subjects with obstructive sleep apnea (OSA), chronic intermittent hypoxia (CIH) may be linked to systemic and adipose tissue inflammation. METHODS. We obtained abdominal subcutaneous adipose tissue biopsies from OSA and non-OSA obese (BMI > 35) subjects at baseline and after 24 weeks (T1) of weight-loss intervention plus continuous positive airway pressure (c-PAP) or weight-loss intervention alone, respectively. OSA subjects were grouped according to good (therapeutic) or poor (subtherapeutic) adherence to c-PAP. RESULTS. At baseline, anthropometric and metabolic parameters, serum cytokines, and adipose tissue mRNA levels of obesity-associated chemokines and inflammatory markers were not different in OSA and non-OSA subjects. At T1, body weight was significantly reduced in all groups. Serum concentrations of IL-2, IL-4, IL-6, MCP-1, PDGFβ, and VEGFα were reduced by therapeutic c-PAP in OSA subjects and remained unaltered in non-OSA and subtherapeutic c-PAP groups. Similarly, adipose tissue mRNA levels of macrophage-specific (CD68, CD36) and ER stress (ATF4, CHOP, ERO-1) gene markers, as well as of IL-6, PDGFβ, and VEGFα, were decreased only in the therapeutic c-PAP group. CONCLUSION. CIH does not represent an additional factor increasing systemic and adipose tissue inflammation in morbid obesity. However, in subjects with OSA, an effective c-PAP therapy improves systemic and obesity-associated inflammatory markers. FUNDING. Ministero dell’Università e della Ricerca and Progetti di Rilevante Interesse Nazionale. PMID:28878129

Exercise (and Estrogen) Make Fat Cells “Fit”

PubMed Central

Vieira-Potter, Victoria J.; Zidon, Terese M.; Padilla, Jaume

2016-01-01

Adipose tissue inflammation links obesity and metabolic disease. Both exercise and estrogen improve metabolic health, enhance mitochondrial function, and have anti-inflammatory effects. We hypothesize that there is an inverse relationship between mitochondrial function and inflammation in adipose tissue and that exercise acts as an estrogen “mimetic”. Explicitly, exercise may improve adipose tissue “immunometabolism” by improving mitochondrial function and reducing inflammation. Summary Exercise improves adipose tissue metabolic health by reducing inflammation and improving mitochondrial function. PMID:25906425

Adipose tissue NAD+-homeostasis, sirtuins and poly(ADP-ribose) polymerases -important players in mitochondrial metabolism and metabolic health.

PubMed

Jokinen, Riikka; Pirnes-Karhu, Sini; Pietiläinen, Kirsi H; Pirinen, Eija

2017-08-01

Obesity, a chronic state of energy overload, is characterized by adipose tissue dysfunction that is considered to be the major driver for obesity associated metabolic complications. The reasons for adipose tissue dysfunction are incompletely understood, but one potential contributing factor is adipose tissue mitochondrial dysfunction. Derangements of adipose tissue mitochondrial biogenesis and pathways associate with obesity and metabolic diseases. Mitochondria are central organelles in energy metabolism through their role in energy derivation through catabolic oxidative reactions. The mitochondrial processes are dependent on the proper NAD + /NADH redox balance and NAD + is essential for reactions catalyzed by the key regulators of mitochondrial metabolism, sirtuins (SIRTs) and poly(ADP-ribose) polymerases (PARPs). Notably, obesity is associated with disturbed adipose tissue NAD + homeostasis and the balance of SIRT and PARP activities. In this review we aim to summarize existing literature on the maintenance of intracellular NAD + pools and the function of SIRTs and PARPs in adipose tissue during normal and obese conditions, with the purpose of comprehending their potential role in mitochondrial derangements and obesity associated metabolic complications. Understanding the molecular mechanisms that are the root cause of the adipose tissue mitochondrial derangements is crucial for developing new effective strategies to reverse obesity associated metabolic complications. Copyright © 2017 The Authors. Published by Elsevier B.V. All rights reserved.

Adipose-derived mesenchymal stem cells from liposuction and resected fat are feasible sources for regenerative medicine.

PubMed

Schneider, Sandra; Unger, Marina; van Griensven, Martijn; Balmayor, Elizabeth R

2017-05-19

The use of mesenchymal stem cells (MSCs) in research and in regenerative medicine has progressed. Bone marrow as a source has drawbacks because of subsequent morbidities. An easily accessible and valuable source is adipose tissue. This type of tissue contains a high number of MSCs, and obtaining higher quantities of tissue is more feasible. Fat tissue can be harvested using different methods such as liposuction and resection. First, a detailed isolation protocol with complete characterization is described. This also includes highlighting problems and pitfalls. Furthermore, some comparisons of these different harvesting methods exist. However, the later characterization of the cells is conducted poorly in most cases. We performed an in-depth characterization over five passages including an investigation of the effect of freezing and thawing. Characterization was performed using flow cytometry with CD markers, metabolic activity with Alamar Blue, growth potential in between passages, and cytoskeleton staining. Our results show that the cells isolated with distinct isolation methods (solid versus liposuction "liquid") have the same MSC potential. However, the percentage of cells positive for the markers CD73, CD90, and CD105 is initially quite low. The cells isolated from the liquid fat tissue grow faster at higher passages, and significantly more cells display MSC markers. In summary, we show a simple and efficient method to isolate adipose-derived mesenchymal stem cells from different preparations. Liposuctions and resection can be used, whereas liposuction has more growth potential at higher passages.

Adipose Dipeptidyl Peptidase-4 and Obesity

PubMed Central

Sell, Henrike; Blüher, Matthias; Klöting, Nora; Schlich, Raphaela; Willems, Miriam; Ruppe, Florian; Knoefel, Wolfram Trudo; Dietrich, Arne; Fielding, Barbara A.; Arner, Peter; Frayn, Keith N.; Eckel, Jürgen

2013-01-01

OBJECTIVE To study expression of the recently identified adipokine dipeptidyl peptidase-4 (DPP4) in subcutaneous adipose tissue (SAT) and visceral adipose tissue (VAT) of patients with various BMIs and insulin sensitivities, as well as to assess circulating DPP4 in relation to obesity and insulin sensitivity. RESEARCH DESIGN AND METHODS DPP4 expression was measured in SAT and VAT from 196 subjects with a wide range of BMIs and insulin sensitivities. DPP4 release was measured ex vivo in paired biopsies from SAT and VAT as well as in vivo from SAT of lean and obese patients. Circulating DPP4 was measured in insulin-sensitive and insulin-resistant BMI-matched obese patients. RESULTS DPP4 expression was positively correlated with BMI in both SAT and VAT, with VAT consistently displaying higher expression than SAT. Ex vivo release of DPP4 from adipose tissue explants was higher in VAT than in SAT in both lean and obese patients, with obese patients displaying higher DPP4 release than lean controls. Net release of DPP4 from adipose tissue was also demonstrated in vivo with greater release in obese subjects than in lean subjects and in women than in men. Insulin-sensitive obese patients had significantly lower circulating DPP4 than did obesity-matched insulin-resistant patients. In this experiment, DPP4 positively correlated with the amount of VAT, adipocyte size, and adipose tissue inflammation. CONCLUSIONS DPP4, a novel adipokine, has a higher release from VAT that is particularly pronounced in obese and insulin-resistant patients. Our data suggest that DPP4 may be a marker for visceral obesity, insulin resistance, and the metabolic syndrome. PMID:24130353

Increased adipose tissue lipolysis after a two-week high-fat diet in sedentary overweight/obese men

PubMed Central

Howe, Harold R; Heidal, Kimberly; Choi, Myung Dong; Kraus, Ray M.; Boyle, Kristen; Hickner, Robert C.

2013-01-01

Background/Objectives The purpose of this study was to determine if a high fat diet would result in a higher lipolytic rate in subcutaneous adipose tissue than a lower fat diet in sedentary non-lean men. Subjects/Methods Six participants (healthy males: 18-40 yrs old: body mass index 25-37 kg/m2) underwent two weeks on a high-fat or well-balanced diet of similar caloric content (approx. 1600 kcal) in randomized order with a ten-day washout period between diets. Subcutaneous abdominal adipose tissue lipolysis was determined over the course of a day using microdialysis after both two-week diet sessions. Results Average interstitial glycerol concentrations (index of lipolysis) as determined using microdialysis were higher following the high-fat diet (210.8 ±27.9 μM) than following a well-balanced diet (175.6 ± 23.3 μM; P = 0.026). There was no difference in adipose tissue microvascular blood flow as determined using the microdialysis ethanol technique. Conclusions These results demonstrate that healthy non-lean men who diet on the high-fat plan have a higher lipolytic rate in subcutaneous abdominal adipose tissue than when they diet on a well-balanced diet plan. This higher rate of lipolysis may result in a higher rate of fat mass loss on the high-fat diet; however, it remains to be determined if this higher lipolytic rate in men on the high-fat diet results in a more rapid net loss of triglyceride from the abdominal adipose depots, or if the higher lipolytic rate is counteracted by an increased rate of lipid storage. PMID:21040937

The Great Roundleaf Bat (Hipposideros armiger) as a Good Model for Cold-Induced Browning of Intra-Abdominal White Adipose Tissue

PubMed Central

Ke, Shanshan; Fang, Na; Irwin, David M.; Lei, Ming; Zhang, Junpeng; Shi, Huizhen; Zhang, Shuyi; Wang, Zhe

2014-01-01

Background Inducing beige fat from white adipose tissue (WAT) is considered to be a shortcut to weight loss and increasingly becoming a key area in research into treatments for obesity and related diseases. However, currently, animal models of beige fat are restricted to rodents, where subcutaneous adipose tissue (sWAT, benign WAT) is more liable to develop into the beige fat under specific activators than the intra-abdominal adipose tissue (aWAT, malignant WAT) that is the major source of obesity related diseases in humans. Methods Here we induced beige fat by cold exposure in two species of bats, the great roundleaf bat (Hipposideros armiger) and the rickett's big-footed bat (Myotis ricketti), and compared the molecular and morphological changes with those seen in the mouse. Expression of thermogenic genes (Ucp1 and Pgc1a) was measured by RT-qPCR and adipocyte morphology examined by HE staining at three adipose locations, sWAT, aWAT and iBAT (interscapular brown adipose tissue). Results Expression of Ucp1 and Pgc1a was significantly upregulated, by 729 and 23 fold, respectively, in aWAT of the great roundleaf bat after exposure to 10°C for 7 days. Adipocyte diameters of WATs became significantly reduced and the white adipocytes became brown-like in morphology. In mice, similar changes were found in the sWAT, but much lower amounts of changes in aWAT were seen. Interestingly, the rickett's big-footed bat did not show such a tendency in beige fat. Conclusions The great roundleaf bat is potentially a good animal model for human aWAT browning research. Combined with rodent models, this model should be helpful for finding therapies for reducing harmful aWAT in humans. PMID:25393240

DNA methylation map in circulating leukocytes mirrors subcutaneous adipose tissue methylation pattern: a genome-wide analysis from non-obese and obese patients

PubMed Central

Crujeiras, A. B.; Diaz-Lagares, A.; Sandoval, J.; Milagro, F. I.; Navas-Carretero, S.; Carreira, M. C.; Gomez, A.; Hervas, D.; Monteiro, M. P.; Casanueva, F. F.; Esteller, M.; Martinez, J. A.

2017-01-01

The characterization of the epigenetic changes within the obesity-related adipose tissue will provide new insights to understand this metabolic disorder, but adipose tissue is not easy to sample in population-based studies. We aimed to evaluate the capacity of circulating leukocytes to reflect the adipose tissue-specific DNA methylation status of obesity susceptibility. DNA samples isolated from subcutaneous adipose tissue and circulating leukocytes were hybridized in the Infinium HumanMethylation 450 BeadChip. Data were compared between samples from obese (n = 45) and non-obese (n = 8–10) patients by Wilcoxon-rank test, unadjusted for cell type distributions. A global hypomethylation of the differentially methylated CpG sites (DMCpGs) was observed in the obese subcutaneous adipose tissue and leukocytes. The overlap analysis yielded a number of genes mapped by the common DMCpGs that were identified to reflect the obesity state in the leukocytes. Specifically, the methylation levels of FGFRL1, NCAPH2, PNKD and SMAD3 exhibited excellent and statistically significant efficiencies in the discrimination of obesity from non-obesity status (AUC > 0.80; p < 0.05) and a great correlation between both tissues. Therefore, the current study provided new and valuable DNA methylation biomarkers of obesity-related adipose tissue pathogenesis through peripheral blood analysis, an easily accessible and minimally invasive biological material instead of adipose tissue. PMID:28211912

Obesity-induced Changes in Adipose Tissue Microenvironment and Their Impact on Cardiovascular Disease

PubMed Central

Fuster, Jose J.; Ouchi, Noriyuki; Gokce, Noyan; Walsh, Kenneth

2016-01-01

Obesity is causally linked with the development of cardiovascular disorders. Accumulating evidence indicates that cardiovascular disease is the “collateral damage” of obesity-driven adipose tissue dysfunction that promotes a chronic inflammatory state within the organism. Adipose tissues secrete bioactive substances, referred to as adipokines, which largely function as modulators of inflammation. The microenvironment of adipose tissue will affect the adipokine secretome, having actions on remote tissues. Obesity typically leads to the upregulation of pro-inflammatory adipokines and the downregulation of anti-inflammatory adipokines, thereby contributing to the pathogenesis of cardiovascular diseases. In this review, we focus on the microenvironment of adipose tissue and how it influences cardiovascular disorders, including atherosclerosis and ischemic heart diseases, through the systemic actions of adipokines. PMID:27230642

Adiponectin/resistin interplay in serum and in adipose tissue of obese and normal-weight individuals.

PubMed

Jonas, Marta Izabela; Kurylowicz, Alina; Bartoszewicz, Zbigniew; Lisik, Wojciech; Jonas, Maurycy; Domienik-Karlowicz, Justyna; Puzianowska-Kuznicka, Monika

2017-01-01

The interplay between adiponectin and resistin, the two adipokines of opposite effects, may determine the metabolic profile of obese individuals and development of obesity-related complications. The current study was conducted to assess how adiponectin/resistin interplay in sera and adipose tissues may influence the metabolic profile of obese and normal-weight subjects. Concentrations of adiponectin and resistin were measured on protein level by immunoassay in visceral and subcutaneous adipose tissues from 50 obese (body mass index > 40 kg/m 2 ) and 28 normal-weight (body mass index 20-24.9 kg/m 2 ) individuals. Simultaneously expression of ADIPOQ and RETN (encoding adiponectin and resistin, respectively) was assessed on mRNA level by real-time PCR. ADIPOQ mRNA (P = 0.0001) and adiponectin protein (P = 0.0013) levels were lower, while RETN mRNA (P = 0.0338) and resistin (P < 0.0001)-higher in subcutaneous adipose tissues of obese subjects. ADIPOQ and RETN mRNA levels did not correlate with protein concentrations in the investigated adipose tissues. In obesity adiponectin serum concentrations correlated positively with ADIPOQ mRNA in subcutaneous adipose tissue (P = 0.005) and negatively with protein levels in visceral adipose tissue (P = 0.001). Obesity was associated with higher adiponectin-resistin index value in sera (P < 0.0001) and decreased in subcutaneous adipose tissue (P < 0.001), but only adiponectin-resistin index measured in sera was significantly higher in obese with the metabolic syndrome (P = 0.04). Obesity affects synthesis of adiponectin and resistin mainly in subcutaneous adipose tissue. The adiponectin-resistin index assessed in the adipose tissues has a different prognostic value compared to the adiponectin-resistin index in serum and does not reflect a metabolic risk in obese individuals.

Adipose tissue content and distribution in children and adolescents with bronchial asthma.

PubMed

Umławska, Wioleta

2015-02-01

The excess of adipose tissue and the pattern of adipose tissue distribution in the body seem to play an important role in the complicated dependencies between obesity and risk of developing asthma. The aim of the present study was to determine nutritional status in children and adolescents with bronchial asthma with special emphasis on adipose tissue distribution evaluated on the basis of skin-fold thicknesses, and to determine the relationships between patterns of adipose tissue distribution and the course of the disease. Anthropometric data on height, weight, circumferences and skin-fold thicknesses were extracted from the medical histories of 261 children diagnosed with asthma bronchitis. Values for children with asthma were compared to Polish national growth reference charts. Distribution of subcutaneous adipose tissue was evaluated using principal components analysis (PCA). Multivariate linear regression analyses tested the effect of three factors on subcutaneous adipose tissue distribution: type of asthma, the severity of the disease and the duration of the disease. Mean body height in the children examined in this study was lower than in their healthy peers. Mean BMI and skin-fold thicknesses were significantly higher and lean body mass was lower in the study group. Excess body fat was noted, especially in girls. Adipose tissue was preferentially deposited in the trunk in girls with severe asthma, as well as in those who had been suffering from asthma for a longer time. The type of asthma, atopic or non-atopic, had no observable effect on subcutaneous adipose tissue distribution in children examined. The data suggest that long-treated subjects and those with severe bronchial asthma accumulate more adipose tissue on the trunk. It is important to regularly monitor nutritional status in children with asthma, especially in those receiving high doses of systemic or inhaled glucocorticosteroids, and long-term treatment as well. Copyright © 2014 Elsevier Ltd. All rights reserved.

The Lymphatic Vasculature: Its Role in Adipose Metabolism and Obesity.

PubMed

Escobedo, Noelia; Oliver, Guillermo

2017-10-03

Obesity is a key risk factor for metabolic and cardiovascular diseases, and although we understand the mechanisms regulating weight and energy balance, the causes of some forms of obesity remain enigmatic. Despite the well-established connections between lymphatics and lipids, and the fact that intestinal lacteals play key roles in dietary fat absorption, the function of the lymphatic vasculature in adipose metabolism has only recently been recognized. It is well established that angiogenesis is tightly associated with the outgrowth of adipose tissue, as expanding adipose tissue requires increased nutrient supply from blood vessels. Results supporting a crosstalk between lymphatic vessels and adipose tissue, and linking lymphatic function with metabolic diseases, obesity, and adipose tissue, also started to accumulate in the last years. Here we review our current knowledge of the mechanisms by which defective lymphatics contribute to obesity and fat accumulation in mouse models, as well as our understanding of the lymphatic-adipose tissue relationship. Copyright © 2017 Elsevier Inc. All rights reserved.

Human Adipose-Derived Mesenchymal Stem Cells Cryopreservation and Thawing Decrease α4-Integrin Expression.

PubMed

Irioda, Ana Carolina; Cassilha, Rafael; Zocche, Larissa; Francisco, Julio Cesar; Cunha, Ricardo Correa; Ferreira, Priscila Elias; Guarita-Souza, Luiz Cesar; Ferreira, Reginaldo Justino; Mogharbel, Bassam Felipe; Garikipati, Venkata Naga Srikanth; Souza, Daiany; Beltrame, Mirian Perlingeiro; de Carvalho, Katherine Athayde Teixeira

2016-01-01

Aim. The effects of cryopreservation on adipose tissue-derived mesenchymal stem cells are not clearly documented, as there is a growing body of evidence about the importance of adipose-derived mesenchymal stem cells for regenerative therapies. The aim of this study was to analyze human adipose tissue-derived mesenchymal stem cells phenotypic expression (CD34, CD45, CD73, CD90, CD105, and CD49d), colony forming unit ability, viability, and differentiation potential before and after cryopreservation. Materials and Methods. 12 samples of the adipose tissue were collected from a healthy donor using the liposuction technique. The cell isolation was performed by enzymatic digestion and then the cells were cultured up to passage 2. Before and after cryopreservation the immunophenotype, cellular viability analysis by flow cytometer, colony forming units ability, differentiation potential into adipocytes and osteoblasts as demonstrated by Oil Red O and Alizarin Red staining, respectively. Results. The immunophenotypic markers expression was largely preserved, and their multipotency was maintained. However, after cryopreservation, the cells decreased α4-integrin expression (CD49d), cell viability, and number of colony forming units. Conclusions. These findings suggest that ADMSC transplanted after cryopreservation might compromise the retention of transplanted cells in the host tissue. Therefore, further studies are warranted to standardize protocols related to cryopreservation to attain full benefits of stem cell therapy.

Altered autophagy in human adipose tissues in obesity

USDA-ARS?s Scientific Manuscript database

Context: Autophagy is a housekeeping mechanism, involved in metabolic regulation and stress response, shown recently to regulate lipid droplets biogenesis/breakdown and adipose tissue phenotype. Objective: We hypothesized that in human obesity autophagy may be altered in adipose tissue in a fat d...

Implication of Low Level Inflammation in the Insulin Resistance of Adipose Tissue at Late Pregnancy

PubMed Central

de Castro, J.; Sevillano, J.; Marciniak, J.; Rodriguez, R.; González-Martín, C.; Viana, M.; Eun-suk, O. H.; de Mouzon, S. Hauguel; Herrera, E.

2011-01-01

Insulin resistance is a characteristic of late pregnancy, and adipose tissue is one of the tissues that most actively contributes to the reduced maternal insulin sensitivity. There is evidence that pregnancy is a condition of moderate inflammation, although the physiological role of this low-grade inflammation remains unclear. The present study was designed to validate whether low-grade inflammation plays a role in the development of insulin resistance in adipose tissue during late pregnancy. To this end, we analyzed proinflammatory adipokines and kinases in lumbar adipose tissue of nonpregnant and late pregnant rats at d 18 and 20 of gestation. We found that circulating and tissue levels of adipokines, such as IL-1β, plasminogen activator inhibitor-1, and TNF-α, were increased at late pregnancy, which correlated with insulin resistance. The observed increase in adipokines coincided with an enhanced activation of p38 MAPK in adipose tissue. Treatment of pregnant rats with the p38 MAPK inhibitor SB 202190 increased insulin-stimulated tyrosine phosphorylation of the insulin receptor (IR) and IR substrate-1 in adipose tissue, which was paralleled by a reduction of IR substrate-1 serine phosphorylation and an enhancement of the metabolic actions of insulin. These results indicate that activation of p38 MAPK in adipose tissue contributes to adipose tissue insulin resistance at late pregnancy. Furthermore, the results of the present study support the hypothesis that physiological low-grade inflammation in the maternal organism is relevant to the development of pregnancy-associated insulin resistance. PMID:21914778

Adipose tissue deficiency of hormone-sensitive lipase causes fatty liver in mice

PubMed Central

Yang, Hao; Wang, Shu Pei; Mitchell, Grant A.

2017-01-01

Fatty liver is a major health problem worldwide. People with hereditary deficiency of hormone-sensitive lipase (HSL) are reported to develop fatty liver. In this study, systemic and tissue-specific HSL-deficient mice were used as models to explore the underlying mechanism of this association. We found that systemic HSL deficient mice developed fatty liver in an age-dependent fashion between 3 and 8 months of age. To further explore the mechanism of fatty liver in HSL deficiency, liver-specific HSL knockout mice were created. Surprisingly, liver HSL deficiency did not influence liver fat content, suggesting that fatty liver in HSL deficiency is not liver autonomous. Given the importance of adipose tissue in systemic triglyceride metabolism, we created adipose-specific HSL knockout mice and found that adipose HSL deficiency, to a similar extent as systemic HSL deficiency, causes age-dependent fatty liver in mice. Mechanistic study revealed that deficiency of HSL in adipose tissue caused inflammatory macrophage infiltrates, progressive lipodystrophy, abnormal adipokine secretion and systemic insulin resistance. These changes in adipose tissue were associated with a constellation of changes in liver: low levels of fatty acid oxidation, of very low density lipoprotein secretion and of triglyceride hydrolase activity, each favoring the development of hepatic steatosis. In conclusion, HSL-deficient mice revealed a complex interorgan interaction between adipose tissue and liver: the role of HSL in the liver is minimal but adipose tissue deficiency of HSL can cause age-dependent hepatic steatosis. Adipose tissue is a potential target for treating the hepatic steatosis of HSL deficiency. PMID:29232702

Adipose tissue deficiency of hormone-sensitive lipase causes fatty liver in mice.

PubMed

Xia, Bo; Cai, Guo He; Yang, Hao; Wang, Shu Pei; Mitchell, Grant A; Wu, Jiang Wei

2017-12-01

Fatty liver is a major health problem worldwide. People with hereditary deficiency of hormone-sensitive lipase (HSL) are reported to develop fatty liver. In this study, systemic and tissue-specific HSL-deficient mice were used as models to explore the underlying mechanism of this association. We found that systemic HSL deficient mice developed fatty liver in an age-dependent fashion between 3 and 8 months of age. To further explore the mechanism of fatty liver in HSL deficiency, liver-specific HSL knockout mice were created. Surprisingly, liver HSL deficiency did not influence liver fat content, suggesting that fatty liver in HSL deficiency is not liver autonomous. Given the importance of adipose tissue in systemic triglyceride metabolism, we created adipose-specific HSL knockout mice and found that adipose HSL deficiency, to a similar extent as systemic HSL deficiency, causes age-dependent fatty liver in mice. Mechanistic study revealed that deficiency of HSL in adipose tissue caused inflammatory macrophage infiltrates, progressive lipodystrophy, abnormal adipokine secretion and systemic insulin resistance. These changes in adipose tissue were associated with a constellation of changes in liver: low levels of fatty acid oxidation, of very low density lipoprotein secretion and of triglyceride hydrolase activity, each favoring the development of hepatic steatosis. In conclusion, HSL-deficient mice revealed a complex interorgan interaction between adipose tissue and liver: the role of HSL in the liver is minimal but adipose tissue deficiency of HSL can cause age-dependent hepatic steatosis. Adipose tissue is a potential target for treating the hepatic steatosis of HSL deficiency.

The Effect of Lipoaspirates on Human Keratinocytes.

PubMed

Kim, Bong-Sung; Gaul, Charel; Paul, Nora E; Dewor, Manfred; Stromps, Jan-Philipp; Hwang, Soo Seok; Nourbakhsh, Mahtab; Bernhagen, Jürgen; Rennekampff, Hans-Oliver; Pallua, Norbert

2016-09-01

One increasingly important trend in plastic, reconstructive, and aesthetic surgery is the use of fat grafts to improve cutaneous wound healing. In clinical practice, lipoaspirates (adipose tissue harvested by liposuction) are re-injected in a procedure called lipofilling. Previous studies, however, mainly evaluated the regenerative effect of isolated adipocytes, adipose-derived stem cells, and excised en bloc adipose tissue on keratinocytes, whereas no study to date has examined the effect of lipoaspirates. The authors aimed to investigate differences in the regenerative property of en bloc adipose tissue and lipoaspirates on keratinocytes. Human keratinocytes, lipoaspirates, and en bloc adipose tissue from 36 healthy donors were isolated. In vitro proliferation, differentiation, migration, stratification, and wound healing of keratinocyte monolayers were measured. Furthermore, secreted levels of VEGF, bFGF, IGF-1, MMP-9, and MIF were detected by ELISA. Migration, proliferation, and wound healing of keratinocytes were increased by lipoaspirates. Interestingly, the effect of lipoaspirates on keratinocyte proliferation was significantly higher than by en bloc adipose tissue after 5 days. The differentiation of keratinocytes was equally attenuated by lipoaspirates and en bloc adipose tissue. Stratification of keratinocyte layers was enhanced by lipoaspirates and en bloc fat when compared to controls. Lipoaspirates secrete higher levels of bFGF, whereas higher levels of VEGF and IGF-1 are released by en bloc adipose tissue. We show that lipoaspirates and en bloc adipose tissue have a regenerative effect on keratinocytes. One reason for the higher effect of lipoaspirates on keratinocyte proliferation may be the secretion of different cytokines. © 2016 The American Society for Aesthetic Plastic Surgery, Inc. Reprints and permission: journals.permissions@oup.com.

Lymphocytes and macrophages in adipose tissue in obesity: markers or makers of subclinical inflammation?

PubMed

Cinkajzlová, Anna; Mráz, Miloš; Haluzík, Martin

2017-05-01

Obesity is accompanied by the development of chronic low-grade inflammation in adipose tissue. The presence of chronic inflammatory response along with metabolically harmful factors released by adipose tissue into the circulation is associated with several metabolic complications of obesity such as type 2 diabetes mellitus or accelerated atherosclerosis. The present review is focused on macrophages and lymphocytes and their possible role in low-grade inflammation in fat. Both macrophages and lymphocytes respond to obesity-induced adipocyte hypertrophy by their migration into adipose tissue. After activation and differentiation, they contribute to the development of local inflammatory response and modulation of endocrine function of adipose tissue. Despite intensive research, the exact role of lymphocytes and macrophages within adipose tissue is only partially clarified and various data obtained by different approaches bring ambiguous information with respect to their polarization and cytokine production. Compared to immunocompetent cells, the role of adipocytes in the obesity-related adipose tissue inflammation is often underestimated despite their abundant production of factors with immunomodulatory actions such as cytokines or adipokines such as leptin, adiponektin, and others. In summary, conflicting evidence together with only partial correlation of in vitro findings with true in vivo situation due to great heterogeneity and molecular complexity of tissue environment calls for intensive research in this rapidly evolving and important area.

Noncanonical Wnt signaling promotes obesity-induced adipose tissue inflammation and metabolic dysfunction independent of adipose tissue expansion.

PubMed

Fuster, José J; Zuriaga, María A; Ngo, Doan Thi-Minh; Farb, Melissa G; Aprahamian, Tamar; Yamaguchi, Terry P; Gokce, Noyan; Walsh, Kenneth

2015-04-01

Adipose tissue dysfunction plays a pivotal role in the development of insulin resistance in obese individuals. Cell culture studies and gain-of-function mouse models suggest that canonical Wnt proteins modulate adipose tissue expansion. However, no genetic evidence supports a role for endogenous Wnt proteins in adipose tissue dysfunction, and the role of noncanonical Wnt signaling remains largely unexplored. Here we provide evidence from human, mouse, and cell culture studies showing that Wnt5a-mediated, noncanonical Wnt signaling contributes to obesity-associated metabolic dysfunction by increasing adipose tissue inflammation. Wnt5a expression is significantly upregulated in human visceral fat compared with subcutaneous fat in obese individuals. In obese mice, Wnt5a ablation ameliorates insulin resistance, in parallel with reductions in adipose tissue inflammation. Conversely, Wnt5a overexpression in myeloid cells augments adipose tissue inflammation and leads to greater impairments in glucose homeostasis. Wnt5a ablation or overexpression did not affect fat mass or adipocyte size. Mechanistically, Wnt5a promotes the expression of proinflammatory cytokines by macrophages in a Jun NH2-terminal kinase-dependent manner, leading to defective insulin signaling in adipocytes. Exogenous interleukin-6 administration restores insulin resistance in obese Wnt5a-deficient mice, suggesting a central role for this cytokine in Wnt5a-mediated metabolic dysfunction. Taken together, these results demonstrate that noncanonical Wnt signaling contributes to obesity-induced insulin resistance independent of adipose tissue expansion. © 2015 by the American Diabetes Association. Readers may use this article as long as the work is properly cited, the use is educational and not for profit, and the work is not altered.

Inhibition of M1 macrophage activation in adipose tissue by berberine improves insulin resistance.

PubMed

Ye, Lifang; Liang, Shu; Guo, Chao; Yu, Xizhong; Zhao, Juan; Zhang, Hao; Shang, Wenbin

2016-12-01

Insulin resistance is associated with a chronic inflammation in adipose tissue which is propagated by a phenotypic switch in adipose tissue macrophage (ATM) polarization. This study aimed to investigate whether berberine, the major alkaloid of rhizoma coptidis, can improve insulin resistance through inhibiting ATM activation and inflammatory response in adipose tissue. High-fat-diet induced obese mice were administered oral with berberine (50mg/kg/day) for 14days. ATMs were analysed using FACS and insulin resistance was evaluated. Expressions of pro-inflammatory cytokines and activation of inflammatory pathways were detected. The chemotaxis of macrophages was measured. Glucose consumption and insulin signalling of adipocytes were examined. Berberine significantly decreased F4/80 + /CD11c + /CD206 - cells in the stromal vascular fraction from adipose tissue and improved glucose tolerance in obsess mice. In addition, berberine reduced the elevated levels of serum TNF-α, IL-6 and MCP-1 and the expressions of TNF-α, IL-6 and MCP-1 and attenuated the phosphorylation of JNK and IKKβ and the expression of NF-κB p65 in the obese adipose tissue, Raw264.7 macrophages and 3T3-L1 adipocytes, respectively. The phosphorylation of IRS-1 (Ser307) was inhibited by berberine in adipose tissue and cultured adipocytes. The phosphorylation of AKT (Ser473) was increased in berberine-treated adipose tissue. Conditioned medium from adipocytes treated with berberine reduced the number of infiltrated macrophages. Berberine partly restored the impaired glucose consumption and the activation of IRS-1 (Ser307) in adipocytes induced by the activation of macrophages. Our findings imply that berberine improves insulin resistance by inhibiting M1 macrophage activation in adipose tissue. Copyright © 2016 Elsevier Inc. All rights reserved.

Effect of luminescence transport through adipose tissue on measurement of tissue temperature by using ZnCdS nanothermometers

NASA Astrophysics Data System (ADS)

Volkova, Elena K.; Yanina, Irina Yu.; Sagaydachnaya, Elena; Konyukhova, Julia G.; Kochubey, Vyacheslav I.; Tuchin, Valery V.

2018-02-01

The spectra of luminescence of ZnCdS nanoparticles (ZnCdS NPs) were measured and analyzed in a wide temperature range: from room to human body and further to a hyperthermic temperature resulting in tissue morphology change. The results show that the signal of luminescence of ZnCdS NPs placed within the tissue is reasonably good sensitive to temperature change and accompanied by phase transitions of lipid structures of adipose tissue. It is shown that the presence of a phase transition in adipose tissue upon its heating (polymorphic transformations of lipids) leads to a nonmonotonic temperature dependence of the intensity of luminescence for the nanoparticles introduced into adipose tissue. This is due to a change in the light scattering by the tissue. The light scattering of adipose tissue greatly distorts the results of temperature measurements. The application of these nanoparticles is possible for temperature measurements in very thin or weakly scattering samples.

High intensity interval training improves liver and adipose tissue insulin sensitivity.

PubMed

Marcinko, Katarina; Sikkema, Sarah R; Samaan, M Constantine; Kemp, Bruce E; Fullerton, Morgan D; Steinberg, Gregory R

2015-12-01

Endurance exercise training reduces insulin resistance, adipose tissue inflammation and non-alcoholic fatty liver disease (NAFLD), an effect often associated with modest weight loss. Recent studies have indicated that high-intensity interval training (HIIT) lowers blood glucose in individuals with type 2 diabetes independently of weight loss; however, the organs affected and mechanisms mediating the glucose lowering effects are not known. Intense exercise increases phosphorylation and inhibition of acetyl-CoA carboxylase (ACC) by AMP-activated protein kinase (AMPK) in muscle, adipose tissue and liver. AMPK and ACC are key enzymes regulating fatty acid metabolism, liver fat content, adipose tissue inflammation and insulin sensitivity but the importance of this pathway in regulating insulin sensitivity with HIIT is unknown. In the current study, the effects of 6 weeks of HIIT were examined using obese mice with serine-alanine knock-in mutations on the AMPK phosphorylation sites of ACC1 and ACC2 (AccDKI) or wild-type (WT) controls. HIIT lowered blood glucose and increased exercise capacity, food intake, basal activity levels, carbohydrate oxidation and liver and adipose tissue insulin sensitivity in HFD-fed WT and AccDKI mice. These changes occurred independently of weight loss or reductions in adiposity, inflammation and liver lipid content. These data indicate that HIIT lowers blood glucose levels by improving adipose and liver insulin sensitivity independently of changes in adiposity, adipose tissue inflammation, liver lipid content or AMPK phosphorylation of ACC.

Testosterone differentially regulates targets of lipid and glucose metabolism in liver, muscle and adipose tissues of the testicular feminised mouse.

PubMed

Kelly, Daniel M; Akhtar, Samia; Sellers, Donna J; Muraleedharan, Vakkat; Channer, Kevin S; Jones, T Hugh

2016-11-01

Testosterone deficiency is commonly associated with obesity, metabolic syndrome, type 2 diabetes and their clinical consequences-hepatic steatosis and atherosclerosis. The testicular feminised mouse (non-functional androgen receptor and low testosterone) develops fatty liver and aortic lipid streaks on a high-fat diet, whereas androgen-replete XY littermate controls do not. Testosterone treatment ameliorates these effects, although the underlying mechanisms remain unknown. We compared the influence of testosterone on the expression of regulatory targets of glucose, cholesterol and lipid metabolism in muscle, liver, abdominal subcutaneous and visceral adipose tissue. Testicular feminised mice displayed significantly reduced GLUT4 in muscle and glycolytic enzymes in muscle, liver and abdominal subcutaneous but not visceral adipose tissue. Lipoprotein lipase required for fatty acid uptake was only reduced in subcutaneous adipose tissue; enzymes of fatty acid synthesis were increased in liver and subcutaneous tissue. Stearoyl-CoA desaturase-1 that catalyses oleic acid synthesis and is associated with insulin resistance was increased in visceral adipose tissue and cholesterol efflux components (ABCA1, apoE) were decreased in subcutaneous and liver tissue. Master regulator nuclear receptors involved in metabolism-Liver X receptor expression was suppressed in all tissues except visceral adipose tissue, whereas PPARγ was lower in abdominal subcutaneous and visceral adipose tissue and PPARα only in abdominal subcutaneous. Testosterone treatment improved the expression (androgen receptor independent) of some targets but not all. These exploratory data suggest that androgen deficiency may reduce the buffering capability for glucose uptake and utilisation in abdominal subcutaneous and muscle and fatty acids in abdominal subcutaneous. This would lead to an overspill and uptake of excess glucose and triglycerides into visceral adipose tissue, liver and arterial walls.

Omega-3-derived mediators counteract obesity-induced adipose tissue inflammation.

PubMed

Titos, Esther; Clària, Joan

2013-12-01

Chronic low-grade inflammation in adipose tissue has been recognized as a key step in the development of obesity-associated complications. In obesity, the accumulation of infiltrating macrophages in adipose tissue and their phenotypic switch to M1-type dysregulate inflammatory adipokine production leading to obesity-linked insulin resistance. Resolvins are potent anti-inflammatory and pro-resolving mediators endogenously generated from omega-3 fatty acids that act as "stop-signals" of the inflammatory response promoting the resolution of inflammation. Recently, a deficit in the production of these endogenous anti-inflammatory signals has been demonstrated in obese adipose tissue. The restoration of their levels by either exogenous administration of these mediators or feeding omega-3-enriched diets, improves the inflammatory status of adipose tissue and ameliorates metabolic dysfunction. Here, we review the current knowledge on the role of these endogenous autacoids in the resolution of adipose tissue inflammation with special emphasis on their functional actions on macrophages. Copyright © 2013 Elsevier Inc. All rights reserved.

Novel Role of Endogenous Catalase in Macrophage Polarization in Adipose Tissue.

PubMed

Park, Ye Seul; Uddin, Md Jamal; Piao, Lingjuan; Hwang, Inah; Lee, Jung Hwa; Ha, Hunjoo

2016-01-01

Macrophages are important components of adipose tissue inflammation, which results in metabolic diseases such as insulin resistance. Notably, obesity induces a proinflammatory phenotypic switch in adipose tissue macrophages, and oxidative stress facilitates this switch. Thus, we examined the role of endogenous catalase, a key regulator of oxidative stress, in the activity of adipose tissue macrophages in obese mice. Catalase knockout (CKO) exacerbated insulin resistance, amplified oxidative stress, and accelerated macrophage infiltration into epididymal white adipose tissue in mice on normal or high-fat diet. Interestingly, catalase deficiency also enhanced classical macrophage activation (M1) and inflammation but suppressed alternative activation (M2) regardless of diet. Similarly, pharmacological inhibition of catalase activity using 3-aminotriazole induced the same phenotypic switch and inflammatory response in RAW264.7 macrophages. Finally, the same phenotypic switch and inflammatory responses were observed in primary bone marrow-derived macrophages from CKO mice. Taken together, the data indicate that endogenous catalase regulates the polarization of adipose tissue macrophages and thereby inhibits inflammation and insulin resistance.

Preparation of a nano emodin transfersome and study on its anti-obesity mechanism in adipose tissue of diet-induced obese rats

PubMed Central

2014-01-01

Objective To describe the preparation of nano emodin transfersome (NET) and investigate its effect on mRNA expression of adipose triglyceride lipase (ATGL) and G0/G1 switch gene 2 (G0S2) in adipose tissue of diet-induced obese rats. Methods NET was prepared by film-ultrasonic dispersion method. The effects of emodin components at different ratios on encapsulation efficiency were investigated.The NET envelopment rate was determined by ultraviolet spectrophotometry. The particle size and Zeta potential of NET were evaluated by Zetasizer analyzer. Sixty male SD rats were assigned to groups randomly. After 8-week treatment, body weight, wet weight of visceral fat and the percentage of body fat (PBF) were measured. Fasting blood glucose and serum lipid levels were determined. The adipose tissue section was HE stained, and the cellular diameter and quantity of adipocytes were evaluated by light microscopy. The mRNA expression of ATGL and G0S2 from the peri-renal fat tissue was assayed by RT-PCR. Results The appropriate formulation was deoxycholic acid sodium salt vs. phospholipids 1:8, cholesterol vs. phospholipids 1:3, vitamin Evs. phospholipids 1:20, and emodin vs. phospholipid 1:6. Zeta potential was −15.11 mV, and the particle size was 292.2 nm. The mean encapsulation efficiency was (69.35 ± 0.25)%. Compared with the obese model group, body weight, wet weight of visceral fat, PBF and mRNA expression of G0S2 from peri-renal fat tissue were decreased significantly after NET treatment (all P < 0.05), while high-density lipoprotein cholesterol (HDL-C), the diameter of adipocytes and mRNA expression of ATGL from peri-renal fat tissue were increased significantly (all P < 0.05). Conclusion The preparation method is simple and reasonable. NET with negative electricity was small and uniform in particle size, with high encapsulation efficiency and stability. NET could reduce body weight and adipocyte size, and this effect was associated with the up-regulation of ATGL, down-regulation of G0S2 expression in the adipose tissue, and improved insulin sensitivity. PMID:24641917

High proportion of PD-1-expressing CD4+ T cells in adipose tissue constitutes an immunomodulatory microenvironment that may support HIV persistence.

PubMed

Damouche, Abderaouf; Pourcher, Guillaume; Pourcher, Valérie; Benoist, Stéphane; Busson, Elodie; Lataillade, Jean-Jacques; Le Van, Mélanie; Lazure, Thierry; Adam, Julien; Favier, Benoit; Vaslin, Bruno; Müller-Trutwin, Michaela; Lambotte, Olivier; Bourgeois, Christine

2017-12-01

We and others have demonstrated that adipose tissue is a reservoir for HIV. Evaluation of the mechanisms responsible for viral persistence may lead to ways of reducing these reservoirs. Here, we evaluated the immune characteristics of adipose tissue in HIV-infected patients receiving antiretroviral therapy (ART) and in non-HIV-infected patients. We notably sought to determine whether adipose tissue's intrinsic properties and/or HIV induced alteration of the tissue environment may favour viral persistence. ART-controlled HIV infection was associated with a difference in the CD4/CD8 T-cell ratio and an elevated proportion of Treg cells in subcutaneous adipose tissue. No changes in Th1, Th2 and Th17 cell proportions or activation markers expression on T cell (Ki-67, HLA-DR) could be detected, and the percentage of CD69-expressing resident memory CD4 + T cells was not affected. Overall, our results indicate that adipose-tissue-resident CD4 + T cells are not extensively activated during HIV infection. PD-1 was expressed by a high proportion of tissue-resident memory CD4 + T cells in both HIV-infected patients and non-HIV-infected patients. Our findings suggest that adipose tissue's intrinsic immunomodulatory properties may limit immune activation and thus may strongly contribute to viral persistence. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

The Metabolic Phenotype in Obesity: Fat Mass, Body Fat Distribution, and Adipose Tissue Function.

PubMed

Goossens, Gijs H

2017-01-01

The current obesity epidemic poses a major public health issue since obesity predisposes towards several chronic diseases. BMI and total adiposity are positively correlated with cardiometabolic disease risk at the population level. However, body fat distribution and an impaired adipose tissue function, rather than total fat mass, better predict insulin resistance and related complications at the individual level. Adipose tissue dysfunction is determined by an impaired adipose tissue expandability, adipocyte hypertrophy, altered lipid metabolism, and local inflammation. Recent human studies suggest that adipose tissue oxygenation may be a key factor herein. A subgroup of obese individuals - the 'metabolically healthy obese' (MHO) - have a better adipose tissue function, less ectopic fat storage, and are more insulin sensitive than obese metabolically unhealthy persons, emphasizing the central role of adipose tissue function in metabolic health. However, controversy has surrounded the idea that metabolically healthy obesity may be considered really healthy since MHO individuals are at increased (cardio)metabolic disease risk and may have a lower quality of life than normal weight subjects due to other comorbidities. Detailed metabolic phenotyping of obese persons will be invaluable in understanding the pathophysiology of metabolic disturbances, and is needed to identify high-risk individuals or subgroups, thereby paving the way for optimization of prevention and treatment strategies to combat cardiometabolic diseases. © 2017 The Author(s) Published by S. Karger GmbH, Freiburg.

Hematopoietic-to-mesenchymal transition of adipose tissue macrophages is regulated by integrin β1 and fabricated fibrin matrices

PubMed Central

Majka, Susan M.; Kohrt, Wendy M.; Miller, Heidi L.; Sullivan, Timothy M.; Klemm, Dwight J.

2017-01-01

ABSTRACT Some bona fide adult adipocytes arise de novo from a bone marrow-derived myeloid lineage. These studies further demonstrate that adipose tissue stroma contains a resident population of myeloid cells capable of adipocyte and multilineage mesenchymal differentiation. These resident myeloid cells lack hematopoietic markers and express mesenchymal and progenitor cell markers. Because bone marrow mesenchymal progenitor cells have not been shown to enter the circulation, we hypothesized that myeloid cells acquire mesenchymal differentiation capacity in adipose tissue. We fabricated a 3-dimensional fibrin matrix culture system to define the adipose differentiation potential of adipose tissue-resident myeloid subpopulations, including macrophages, granulocytes and dendritic cells. Our data show that multilineage mesenchymal potential was limited to adipose tissue macrophages, characterized by the acquisition of adipocyte, osteoblast, chondrocyte and skeletal muscle myocyte phenotypes. Fibrin hydrogel matrices stimulated macrophage loss of hematopoietic cell lineage determinants and the expression of mesenchymal and progenitor cell markers, including integrin β1. Ablation of integrin β1 in macrophages inhibited adipocyte specification. Therefore, some bona fide adipocytes are specifically derived from adipose tissue-resident macrophages via an integrin β1-dependent hematopoietic-to-mesenchymal transition, whereby they become capable of multipotent mesenchymal differentiation. The requirement for integrin β1 highlights this molecule as a potential target for controlling the production of marrow-derived adipocytes and their contribution to adipose tissue development and function. PMID:28441086

Interleukin-17A Differentially Induces Inflammatory and Metabolic Gene Expression in the Adipose Tissues of Lean and Obese Mice

PubMed Central

Qu, Yine; Zhang, Qiuyang; Ma, Siqi; Liu, Sen; Chen, Zhiquan; Mo, Zhongfu; You, Zongbing

2016-01-01

The functions of interleukin-17A (IL-17A) in adipose tissues and adipocytes have not been well understood. In the present study, male mice were fed with a regular diet (n = 6, lean mice) or a high-fat diet (n = 6, obese mice) for 30 weeks. Subcutaneous adipose tissue (SAT) and visceral adipose tissue (VAT) were analyzed for IL-17A levels. SAT and VAT were treated with IL-17A and analyzed for inflammatory and metabolic gene expression. Mouse 3T3-L1 pre-adipocytes were differentiated into adipocytes, followed with IL-17A treatment and analysis for inflammatory and metabolic gene expression. We found that IL-17A levels were higher in obese SAT than lean SAT; the basal expression of inflammatory and metabolic genes was different between SAT and VAT and between lean and obese adipose tissues. IL-17A differentially induced expression of inflammatory and metabolic genes, such as tumor necrosis factor α, Il-6, Il-1β, leptin, and glucose transporter 4, in adipose tissues of lean and obese mice. IL-17A also differentially induced expression of inflammatory and metabolic genes in pre-adipocytes and adipocytes, and IL-17A selectively activated signaling pathways in adipose tissues and adipocytes. These findings suggest that IL-17A differentially induces inflammatory and metabolic gene expression in the adipose tissues of lean and obese mice. PMID:27070576

Quantifying the effect of adipose tissue in muscle oximetry by near infrared spectroscopy

PubMed Central

Nasseri, Nassim; Kleiser, Stefan; Ostojic, Daniel; Karen, Tanja; Wolf, Martin

2016-01-01

Change of muscle tissue oxygen saturation (StO2), due to exercise, measured by near infrared spectroscopy (NIRS) is known to be lower for subjects with higher adipose tissue thickness. This is most likely not physiological but caused by the superficial fat and adipose tissue. In this paper we assessed, in vitro, the influence of adipose tissue thickness on muscle StO2, measured by NIRS oximeters. We measured StO2 of a liquid phantom by 3 continuous wave (CW) oximeters (Sensmart Model X-100 Universal Oximetry System, INVOS 5100C, and OxyPrem v1.3), as well as a frequency-domain oximeter, OxiplexTS, through superficial layers with 4 different thicknesses. Later, we employed the results to calibrate OxyPrem v1.3 for adipose tissue thickness in-vivo. PMID:27895999

The role of adenosine monophosphate kinase in remodeling white adipose tissue metabolism.

PubMed

Gaidhu, Mandeep Pinky; Ceddia, Rolando Bacis

2011-04-01

Recent evidence indicates that the enzyme adenosine monophosphate (AMP) kinase exerts important fat-reducing effects in the adipose tissue, which has created great interest in this enzyme as a potential target for obesity treatment. This review summarizes our findings that chronic AMP kinase activation remodels adipocyte glucose and lipid metabolism and enhances the ability of adipose tissue to dissipate energy within itself and reduce adiposity.

Adipose-Derived Stem Cells for Tissue Engineering and Regenerative Medicine Applications

PubMed Central

Dai, Ru; Wang, Zongjie; Samanipour, Roya; Koo, Kyo-in; Kim, Keekyoung

2016-01-01

Adipose-derived stem cells (ASCs) are a mesenchymal stem cell source with properties of self-renewal and multipotential differentiation. Compared to bone marrow-derived stem cells (BMSCs), ASCs can be derived from more sources and are harvested more easily. Three-dimensional (3D) tissue engineering scaffolds are better able to mimic the in vivo cellular microenvironment, which benefits the localization, attachment, proliferation, and differentiation of ASCs. Therefore, tissue-engineered ASCs are recognized as an attractive substitute for tissue and organ transplantation. In this paper, we review the characteristics of ASCs, as well as the biomaterials and tissue engineering methods used to proliferate and differentiate ASCs in a 3D environment. Clinical applications of tissue-engineered ASCs are also discussed to reveal the potential and feasibility of using tissue-engineered ASCs in regenerative medicine. PMID:27057174

Adipose tissue and the reproductive axis: biological aspects

USDA-ARS?s Scientific Manuscript database

The discovery of leptin clearly demonstrated a relationship between body fat and the neuroendocrine axis since leptin influences appetite and the reproductive axis. Since adipose tissue is a primary source of leptin, adipose tissue is no longer considered as simply a depot to store fat. Recent find...

Maternal high-fat diet modulates brown adipose tissue response to B-adrenergic agonist

USDA-ARS?s Scientific Manuscript database

Maternal obesity increases offspring risk for several metabolic diseases. We previously showed that offspring of obese dams are predisposed to obesity, liver and adipose tissue anomalies. However, the effect of maternal obesity on developmental programing brown adipose tissue (BAT) is poorly underst...

Epicardial adipose tissue is associated with visceral fat, metabolic syndrome, and insulin resistance in menopausal women.

PubMed

Fernández Muñoz, María J; Basurto Acevedo, Lourdes; Córdova Pérez, Nydia; Vázquez Martínez, Ana Laura; Tepach Gutiérrez, Nayive; Vega García, Sara; Rocha Cruz, Alberto; Díaz Martínez, Alma; Saucedo García, Renata; Zárate Treviño, Arturo; González Escudero, Eduardo Alberto; Degollado Córdova, José Antonio

2014-06-01

Epicardial adipose tissue has been associated with several obesity-related parameters and with insulin resistance. Echocardiographic assessment of this tissue is an easy and reliable marker of cardiometabolic risk. However, there are insufficient studies on the relationship between epicardial fat and insulin resistance during the postmenopausal period, when cardiovascular risk increases in women. The objective of this study was to examine the association between epicardial adipose tissue and visceral adipose tissue, waist circumference, body mass index, and insulin resistance in postmenopausal women. A cross sectional study was conducted in 34 postmenopausal women with and without metabolic syndrome. All participants underwent a transthoracic echocardiogram and body composition analysis. A positive correlation was observed between epicardial fat and visceral adipose tissue, body mass index, and waist circumference. The values of these correlations of epicardial fat thickness overlying the aorta-right ventricle were r = 0.505 (P < .003), r = 0.545 (P < .001), and r = 0.515 (P < .003), respectively. Epicardial adipose tissue was higher in postmenopausal women with metabolic syndrome than in those without this syndrome (mean [standard deviation], 544.2 [122.9] vs 363.6 [162.3] mm(2); P = .03). Epicardial fat thickness measured by echocardiography was associated with visceral adipose tissue and other obesity parameters. Epicardial adipose tissue was higher in postmenopausal women with metabolic syndrome. Therefore, echocardiographic assessment of epicardial fat may be a simple and reliable marker of cardiovascular risk in postmenopausal women. Copyright © 2013 Sociedad Española de Cardiología. Published by Elsevier Espana. All rights reserved.

Peroxisome Proliferator-Activated Receptor (PPAR) in Regenerative Medicine: Molecular Mechanism for PPAR in Stem Cells' Adipocyte Differentiation.

PubMed

Xie, Qiang; Tian, Taoran; Chen, Zhaozhao; Deng, Shuwen; Sun, Ke; Xie, Jing; Cai, Xiaoxiao

2016-01-01

Regenerative medicine plays an indispensable role in modern medicine and many trials and researches have therefore been developed to fit our medical needs. Tissue engineering has proven that adipose tissue can widely be used and brings advantages to regenerative medicine. Moreover, a trait of adipose stem cells being isolated and grown in vitro is a cornerstone to various applications. Since the adipose tissue has been widely used in regenerative medicine, numerous studies have been conducted to seek methods for gaining more adipocytes. To investigate molecular mechanism for adipocyte differentiation, peroxisome proliferator-activated receptor (PPAR) has been widely studied to find out its functional mechanism, as a key factor for adipocyte differentiation. However, the precise molecular mechanism is still unknown. This review thus summarizes recent progress on the study of molecular mechanism and role of PPAR in adipocyte differentiation.

Biologically and mechanically driven design of an RGD-mimetic macroporous foam for adipose tissue engineering applications.

PubMed

Rossi, Eleonora; Gerges, Irini; Tocchio, Alessandro; Tamplenizza, Margherita; Aprile, Paola; Recordati, Camilla; Martello, Federico; Martin, Ivan; Milani, Paolo; Lenardi, Cristina

2016-10-01

Despite clinical treatments for adipose tissue defects, in particular breast tissue reconstruction, have certain grades of efficacy, many drawbacks are still affecting the long-term survival of new formed fat tissue. To overcome this problem, in the last decades, several scaffolding materials have been investigated in the field of adipose tissue engineering. However, a strategy able to recapitulate a suitable environment for adipose tissue reconstruction and maintenance is still missing. To address this need, we adopted a biologically and mechanically driven design to fabricate an RGD-mimetic poly(amidoamine) oligomer macroporous foam (OPAAF) for adipose tissue reconstruction. The scaffold was designed to fulfil three fundamental criteria: capability to induce cell adhesion and proliferation, support of in vivo vascularization and match of native tissue mechanical properties. Poly(amidoamine) oligomers were formed into soft scaffolds with hierarchical porosity through a combined free radical polymerization and foaming reaction. OPAAF is characterized by a high water uptake capacity, progressive degradation kinetics and ideal mechanical properties for adipose tissue reconstruction. OPAAF's ability to support cell adhesion, proliferation and adipogenesis was assessed in vitro using epithelial, fibroblast and endothelial cells (MDCK, 3T3L1 and HUVEC respectively). In addition, in vivo subcutaneous implantation in murine model highlighted OPAAF potential to support both adipogenesis and vessels infiltration. Overall, the reported results support the use of OPAAF as a scaffold for engineered adipose tissue construct. Copyright © 2016 Elsevier Ltd. All rights reserved.

(1)H nuclear magnetic resonance (NMR) as a tool to measure dehydration in mice.

PubMed

Li, Matthew; Vassiliou, Christophoros C; Colucci, Lina A; Cima, Michael J

2015-08-01

Dehydration is a prevalent pathology, where loss of bodily water can result in variable symptoms. Symptoms can range from simple thirst to dire scenarios involving loss of consciousness. Clinical methods exist that assess dehydration from qualitative weight changes to more quantitative osmolality measurements. These methods are imprecise, invasive, and/or easily confounded, despite being practiced clinically. We investigate a non-invasive, non-imaging (1)H NMR method of assessing dehydration that attempts to address issues with existing clinical methods. Dehydration was achieved by exposing mice (n = 16) to a thermally elevated environment (37 °C) for up to 7.5 h (0.11-13% weight loss). Whole body NMR measurements were made using a Bruker LF50 BCA-Analyzer before and after dehydration. Physical lean tissue, adipose, and free water compartment approximations had NMR values extracted from relaxation data through a multi-exponential fitting method. Changes in before/after NMR values were compared with clinically practiced metrics of weight loss (percent dehydration) as well as blood and urine osmolality. A linear correlation between tissue relaxometry and both animal percent dehydration and urine osmolality was observed in lean tissue, but not adipose or free fluids. Calculated R(2) values for percent dehydration were 0.8619 (lean, P < 0.0001), 0.5609 (adipose, P = 0.0008), and 0.0644 (free fluids, P = 0.3445). R(2) values for urine osmolality were 0.7760 (lean, P < 0.0001), 0.5005 (adipose, P = 0.0022), and 0.0568 (free fluids, P = 0.3739). These results suggest that non-imaging (1)H NMR methods are capable of non-invasively assessing dehydration in live animals. Copyright © 2015 John Wiley & Sons, Ltd.

Efficacy of thigh volume ratios assessed via stereovision body imaging as a predictor of visceral adipose tissue measured by magnetic resonance imaging.

PubMed

Lee, Jane J; Freeland-Graves, Jeanne H; Pepper, M Reese; Yu, Wurong; Xu, Bugao

2015-01-01

The research examined the efficacy of regional volumes of thigh ratios assessed by stereovision body imaging (SBI) as a predictor of visceral adipose tissue measured by magnetic resonance imaging (MRI). Body measurements obtained via SBI also were utilized to explore disparities of body size and shape in men and women. One hundred twenty-one participants were measured for total/regional body volumes and ratios via SBI and abdominal subcutaneous and visceral adipose tissue areas by MRI. Thigh to torso and thigh to abdomen-hip volume ratios were the most reliable parameters to predict the accumulation of visceral adipose tissue depots compared to other body measurements. Thigh volume in relation to torso [odds ratios (OR) 0.44] and abdomen-hip (OR 0.41) volumes were negatively associated with increased risks of greater visceral adipose tissue depots, even after controlling for age, gender, and body mass index (BMI). Irrespective of BMI classification, men exhibited greater total body (80.95L vs. 72.41L), torso (39.26L vs. 34.13L), and abdomen-hip (29.01L vs. 25.85L) volumes than women. Women had higher thigh volumes (4.93L vs. 3.99L) and lower-body volume ratios [thigh to total body (0.07 vs. 0.05), thigh to torso (0.15 vs. 0.11), and thigh to abdomen-hip (0.20 vs. 0.15); P < 0.05]. The unique parameters of the volumes of thigh in relation to torso and abdomen-hip, by SBI were highly effective in predicting visceral adipose tissue deposition. The SBI provided an efficient method for determining body size and shape in men and women via total and regional body volumes and ratios. Am. J. Hum. Biol. 27:445-457, 2015. © 2015 Wiley Periodicals, Inc. © 2015 Wiley Periodicals, Inc.

Wnt inhibition enhances browning of mouse primary white adipocytes.

PubMed

Lo, Kinyui Alice; Ng, Pei Yi; Kabiri, Zahra; Virshup, David; Sun, Lei

2016-01-01

The global epidemic in obesity and metabolic syndrome requires novel approaches to tackle. White adipose tissue, traditionally seen as a passive energy-storage organ, can be induced to take on certain characteristics of brown fat in a process called browning. The "browned" white adipose tissue, or beige fat, is a potential anti-obesity target. Various signaling pathways can enhance browning. Wnt is a key regulator of adipocyte biology, but its role in browning has not been explored. In this study, we found that in primary mouse adipocytes derived from the inguinal depot, Wnt inhibition by both chemical and genetic methods significantly enhanced browning. The effect of Wnt inhibition on browning most likely targets the beige precursor cells in selected adipose depots.

Hypercholesterolemia induces adipose dysfunction in conditions of obesity and nonobesity.

PubMed

Aguilar, David; Fernandez, Maria Luz

2014-09-01

It is well known that hypercholesterolemia can lead to atherosclerosis and coronary heart disease. Adipose tissue represents an active endocrine and metabolic site, which might be involved in the development of chronic disease. Because adipose tissue is a key site for cholesterol metabolism and the presence of hypercholesterolemia has been shown to induce adipocyte cholesterol overload, it is critical to investigate the role of hypercholesterolemia on normal adipose function. Studies in preadipocytes revealed that cholesterol accumulation can impair adipocyte differentiation and maturation by affecting multiple transcription factors. Hypercholesterolemia has been observed to cause adipocyte hypertrophy, adipose tissue inflammation, and disruption of endocrine function in animal studies. Moreover, these effects can also be observed in obesity-independent conditions as confirmed by clinical trials. In humans, hypercholesterolemia disrupts adipose hormone secretion of visfatin, leptin, and adiponectin, adipokines that play a central role in numerous metabolic pathways and regulate basic physiologic responses such as appetite and satiety. Remarkably, treatment with cholesterol-lowering drugs has been shown to restore adipose tissue endocrine function. In this review the role of hypercholesterolemia on adipose tissue differentiation and maturation, as well as on hormone secretion and physiologic outcomes, in obesity and non–obesity conditions is presented.

Early overfeed-induced obesity leads to brown adipose tissue hypoactivity in rats.

PubMed

de Almeida, Douglas L; Fabrício, Gabriel S; Trombini, Amanda B; Pavanello, Audrei; Tófolo, Laize P; da Silva Ribeiro, Tatiane A; de Freitas Mathias, Paulo C; Palma-Rigo, Kesia

2013-01-01

Brown adipose tissue activation has been considered a potential anti-obesity mechanism because it is able to expend energy through thermogenesis. In contrast, white adipose tissue stores energy, contributing to obesity. We investigated whether the early programming of obesity by overfeeding during lactation changes structure of interscapular brown adipose tissue in adulthood and its effects on thermogenesis. Birth of litters was considered day 0. On day 2, litter size was adjusted to normal (9 pups) and small (3 pups) litters. On day 21, the litters were weaned. A temperature transponder was implanted underneath interscapular brown adipose tissue pads of 81-day-old animals; local temperature was measured during light and dark periods between days 87 and 90. The animals were euthanized, and tissue and blood samples were collected for further analysis. The vagus and retroperitoneal sympathetic nerve activity was recorded. Small litter rats presented significant lower interscapular brown adipose tissue temperature during the light (NL 37.6°C vs. SL 37.2°C) and dark (NL 38°C vs. SL 37.6°C) periods compared to controls. Morphology of small litter brown adipose tissue showed fewer lipid droplets in the tissue center and more and larger in the periphery. The activity of vagus nerve was 19,9% greater in the small litter than in control (p<0.01), and no difference was observed in the sympathetic nerve activity. In adulthood, the small litter rats were 11,7% heavier than the controls and presented higher glycemia 13,1%, insulinemia 70% and corticosteronemia 92,6%. Early overfeeding programming of obesity changes the interscapular brown adipose tissue structure in adulthood, leading to local thermogenesis hypoactivity, which may contribute to obesity in adults. © 2013 S. Karger AG, Basel.

Molecular effects of leptin on peroxisome proliferator activated receptor gamma (PPAR-γ) mRNA expression in rat's adipose and liver tissue.

PubMed

Abbasi, A; Moghadam, A A; Kahrarian, Z; Abbsavaran, R; Yari, K; Alizadeh, E

2017-08-15

Leptin is a 16-kDa peptide hormone secreted by adipose tissue that participates in the regulation of energy homeostasis. The aim of this study was to determine the effect of leptin injection on mRNA expression of peroxisome proliferator-activated receptor gamma (PPAR-γ) and comparison of PPAR-γ mRNA expression in rat's adipose and liver tissue. Twenty adult male rats were divided into the following groups: Group 1asa control (n=10) that did not receive any treatment. Group 2as a treatment (n=10) that received leptin (30 µg ⁄ kg BW) intraperitoneally (ip) for two successive days. Blood samples were taken before and one day after second leptin injection for triglyceride (TG), Free Fatty Acid (FFA), HLD-cholesterol, and LDL-cholesterol measurement. Total RNA was extractedfrom the adipose tissue and liver tissues of rats.  Adipose and liver tissue cells' cDNA was synthesized to characterize the expression of PPAR-γ. Gene expression of PPAR-γ mRNA was tested by RT- PCR technique. Results show leptin decreases expression of PPAR-γ on rat. Low levels of PPAR-γ mRNA were detected in adipose and liver tissues of treatment rats in comparison to control group. In treatment group, the level of PPAR-γ mRNA in liver tissue was very lower than the adipose tissue. The levels of HDL and FFA in treatment rats were increased whereas serum levels TG, VLDL and LDL were not changed. It is concluded that leptin signal with suppressing of PPAR-γ mRNA expression in rat's adipose and liver tissues can result in lipolysis instead of lipogenesis.

VAT=TAAT-SAAT: Innovative Anthropometric Model to Predict Visceral Adipose Tissue Without Resort to CT-Scan or DXA

PubMed Central

Samouda, Hanen; Dutour, Anne; Chaumoitre, Kathia; Panuel, Michel; Dutour, Olivier; Dadoun, Frédéric

2013-01-01

Objective To investigate whether a combination of a selected but limited number of anthropometric measurements predicts visceral adipose tissue (VAT) better than other anthropometric measurements, without resort to medical imaging. Hypothesis Abdominal anthropometric measurements are total abdominal adipose tissue indicators and global measures of VAT and SAAT (subcutaneous abdominal adipose tissue). Therefore, subtracting the anthropometric measurement the more correlated possible with SAAT while being the least correlated possible with VAT, from the most correlated abdominal anthropometric measurement with VAT while being highly correlated with TAAT, may better predict VAT. Design and Methods BMI participants' range was from 16.3 to 52.9 kg m−2. Anthropometric and abdominal adipose tissues data by computed tomography (CT-Scan) were available in 253 patients (18-78 years) (CHU Nord, Marseille) and used to develop the anthropometric VAT prediction models. Results Subtraction of proximal thigh circumference from waist circumference, adjusted to age and/or BMI, predicts better VAT (Women: VAT = 2.15 × Waist C − 3.63 × Proximal Thigh C + 1.46 × Age + 6.22 × BMI − 92.713; R2 = 0.836. Men: VAT = 6 × Waist C − 4.41 × proximal thigh C + 1.19 × Age − 213.65; R2 = 0.803) than the best single anthropometric measurement or the association of two anthropometric measurements highly correlated with VAT. Both multivariate models showed no collinearity problem. Selected models demonstrate high sensitivity (97.7% in women, 100% in men). Similar predictive abilities were observed in the validation sample (Women: R2 = 76%; Men: R2 = 70%). Bland and Altman method showed no systematic estimation error of VAT. Conclusion Validated in a large range of age and BMI, our results suggest the usefulness of the anthropometric selected models to predict VAT in Europides (South of France). PMID:23404678

Deficiency in adipocyte chemokine receptor CXCR4 exacerbates obesity and compromises thermoregulatory responses of brown adipose tissue in a mouse model of diet-induced obesity

PubMed Central

Yao, Longbiao; Heuser-Baker, Janet; Herlea-Pana, Oana; Zhang, Nan; Szweda, Luke I.; Griffin, Timothy M.; Barlic-Dicen, Jana

2014-01-01

The chemokine receptor CXCR4 is expressed on adipocytes and macrophages in adipose tissue, but its role in this tissue remains unknown. We evaluated whether deficiency in either adipocyte or myeloid leukocyte CXCR4 affects body weight (BW) and adiposity in a mouse model of high-fat-diet (HFD)-induced obesity. We found that ablation of adipocyte, but not myeloid leukocyte, CXCR4 exacerbated obesity. The HFD-fed adipocyte-specific CXCR4-knockout (AdCXCR4ko) mice, compared to wild-type C57BL/6 control mice, had increased BW (average: 52.0 g vs. 35.5 g), adiposity (average: 49.3 vs. 21.0% of total BW), and inflammatory leukocyte content in white adipose tissue (WAT), despite comparable food intake. As previously reported, HFD feeding increased uncoupling protein 1 (UCP1) expression (fold increase: 3.5) in brown adipose tissue (BAT) of the C57BL/6 control mice. However, no HFD-induced increase in UCP1 expression was observed in the AdCXCR4ko mice, which were cold sensitive. Thus, our study suggests that adipocyte CXCR4 limits development of obesity by preventing excessive inflammatory cell recruitment into WAT and by supporting thermogenic activity of BAT. Since CXCR4 is conserved between mouse and human, the newfound role of CXCR4 in mouse adipose tissue may parallel the role of this chemokine receptor in human adipose tissue.—Yao, L., Heuser-Baker, J., Herlea-Pana, O., Zhang, N., Szweda, L. I., Griffin, T. M., Barlic-Dicen, J. Deficiency in adipocyte chemokine receptor CXCR4 exacerbates obesity and compromises thermoregulatory responses of brown adipose tissue in a mouse model of diet-induced obesity. PMID:25016030

Lipocalin 2, a Regulator of Retinoid Homeostasis and Retinoid-mediated Thermogenic Activation in Adipose Tissue*

PubMed Central

Guo, Hong; Foncea, Rocio; O'Byrne, Sheila M.; Jiang, Hongfeng; Zhang, Yuanyuan; Deis, Jessica A.; Blaner, William S.; Bernlohr, David A.; Chen, Xiaoli

2016-01-01

We have recently characterized the role of lipocalin 2 (Lcn2) as a new adipose-derived cytokine in the regulation of adaptive thermogenesis via a non-adrenergic pathway. Herein, we explored a potential non-adrenergic mechanism by which Lcn2 regulates thermogenesis and lipid metabolism. We found that Lcn2 is a retinoic acid target gene, and retinoic acid concurrently stimulated UCP1 and Lcn2 expression in adipocytes. Lcn2 KO mice exhibited a blunted effect of all-trans-retinoic acid (ATRA) on body weight and fat mass, lipid metabolism, and retinoic acid signaling pathway activation in adipose tissue under the high fat diet-induced obese condition. We further demonstrated that Lcn2 is required for the full action of ATRA on the induction of UCP1 and PGC-1α expression in brown adipocytes and the restoration of cold intolerance in Lcn2 KO mice. Interestingly, we discovered that Lcn2 KO mice have decreased levels of retinoic acid and retinol in adipose tissue. The protein levels of STRA6 responsible for retinol uptake were significantly decreased in adipose tissue. The retinol transporter RBP4 was increased in adipose tissue but decreased in the circulation, suggesting the impairment of RBP4 secretion in Lcn2 KO adipose tissue. Moreover, Lcn2 deficiency abolished the ATRA effect on RBP4 expression in adipocytes. All the data suggest that the decreased retinoid level and action are associated with impaired retinol transport and storage in adipose tissue in Lcn2 KO mice. We conclude that Lcn2 plays a critical role in regulating metabolic homeostasis of retinoids and retinoid-mediated thermogenesis in adipose tissue. PMID:27008859

Berberine alleviates adipose tissue fibrosis by inducing AMP-activated kinase signaling in high-fat diet-induced obese mice.

PubMed

Wang, Lijun; Ye, Xiao; Hua, Yanyin; Song, Yingxiang

2018-05-28

Adipose tissue fibrosis is a novel mechanism for the development of obesity related insulin resistance. Berberine (BBR) has been shown to relieve several metabolic disorders, including obesity and type 2 diabetes. However, the effects of BBR on obesity related adipose fibrosis remain poorly understood. The objective of this study was to assess the effects of BBR on adipose tissue fibrosis in high fat diet (HFD)-induced obese mice. The results showed that BBR reduced animal body weight and significantly improved glucose tolerance in HFD mice. In addition, BBR treatment markedly attenuated collagen deposition and reversed the up-regulation of fibrosis associated genes in the adipose tissue of HFD mice. Moreover, BBR treatment activated AMP-activated kinase signaling and reduced TGF-β1 and Smad3 phosphorylation. Of note, the inhibitory effects of BBR on adipose tissue fibrosis were significantly blocked by AMPK inhibition with compound C, an AMPK inhibitor. Macrophage infiltration and polarization induced by HFD were also reversed after BBR administration. These findings suggest that BBR displays beneficial effects in the treatment of obesity, in part via improvement of adipose tissue fibrosis. Copyright © 2018 Elsevier Masson SAS. All rights reserved.

Cell supermarket: Adipose tissue as a source of stem cells

USDA-ARS?s Scientific Manuscript database

Adipose tissue is derived from numerous sources, and in recent years has been shown to provide numerous cells from what seemingly was a population of homogeneous adipocytes. Considering the types of cells that adipose tissue-derived cells may form, these cells may be useful in a variety of clinical ...

Modulations of calcium in adipose tissue by TRPC1: a key player in obesity

USDA-ARS?s Scientific Manuscript database

The disruption of metabolic homeostasis, the regulation of energy the body extracts, stores and uses, leads to excess adipose tissue accumulation and the onset of obesity. White adipose tissue (WAT) is a metabolically dynamic endocrine organ responsible for maintaining metabolic homeostasis through ...

Pseudolipomatosis in Endometrial Specimens Does Not Represent Uterine Perforation.

PubMed

Heller, Alexis

2017-02-01

Specimens of endometrial biopsies can sometimes present with an artifact within blood, composed of optically clear vacuoles mimicking adipose tissue, pseudolipomatosis. This artifact can be mistaken for adipose tissue and lead to an overdiagnosis of uterine perforation. We describe the case of pseudolipomatosis seen within the evacuated products of conception from a missed abortion. Areas of vacuolization in the blood clot mimicked adipose tissue. However, the vacuoles varied in size and did not contain adipocytes. Familiarity with this artifact will lead to avoidance of overdiagnosis of adipose tissue and uterine perforation in curettage specimens.

ERα upregulates Phd3 to ameliorate HIF-1 induced fibrosis and inflammation in adipose tissue

PubMed Central

Kim, Min; Neinast, Michael D.; Frank, Aaron P.; Sun, Kai; Park, Jiyoung; Zehr, Jordan A.; Vishvanath, Lavanya; Morselli, Eugenia; Amelotte, Mason; Palmer, Biff F.; Gupta, Rana K.; Scherer, Philipp E.; Clegg, Deborah J.

2014-01-01

Hypoxia Inducible Factor 1 (HIF-1) promotes fibrosis and inflammation in adipose tissues, while estrogens and Estrogen Receptor α (ERα) have the opposite effect. Here we identify an Estrogen Response Element (ERE) in the promoter of Phd3, which is a negative regulatory enzyme of HIF-1, and we demonstrate HIF-1α is ubiquitinated following 17-β estradiol (E2)/ERα mediated Phd3 transcription. Manipulating ERα in vivo increases Phd3 transcription and reduces HIF-1 activity, while addition of PHD3 ameliorates adipose tissue fibrosis and inflammation. Our findings outline a novel regulatory relationship between E2/ERα, PHD3 and HIF-1 in adipose tissues, providing a mechanistic explanation for the protective effect of E2/ERα in adipose tissue. PMID:25161887

Impact of Perturbed Pancreatic β-Cell Cholesterol Homeostasis on Adipose Tissue and Skeletal Muscle Metabolism

PubMed Central

Cochran, Blake J.; Hou, Liming; Manavalan, Anil Paul Chirackal; Moore, Benjamin M.; Tabet, Fatiha; Sultana, Afroza; Cuesta Torres, Luisa; Tang, Shudi; Shrestha, Sudichhya; Senanayake, Praween; Patel, Mili; Ryder, William J.; Bongers, Andre; Maraninchi, Marie; Wasinger, Valerie C.; Westerterp, Marit; Tall, Alan R.; Barter, Philip J.

2016-01-01

Elevated pancreatic β-cell cholesterol levels impair insulin secretion and reduce plasma insulin levels. This study establishes that low plasma insulin levels have a detrimental effect on two major insulin target tissues: adipose tissue and skeletal muscle. Mice with increased β-cell cholesterol levels were generated by conditional deletion of the ATP-binding cassette transporters, ABCA1 and ABCG1, in β-cells (β-DKO mice). Insulin secretion was impaired in these mice under basal and high-glucose conditions, and glucose disposal was shifted from skeletal muscle to adipose tissue. The β-DKO mice also had increased body fat and adipose tissue macrophage content, elevated plasma interleukin-6 and MCP-1 levels, and decreased skeletal muscle mass. They were not, however, insulin resistant. The adipose tissue expansion and reduced skeletal muscle mass, but not the systemic inflammation or increased adipose tissue macrophage content, were reversed when plasma insulin levels were normalized by insulin supplementation. These studies identify a mechanism by which perturbation of β-cell cholesterol homeostasis and impaired insulin secretion increase adiposity, reduce skeletal muscle mass, and cause systemic inflammation. They further identify β-cell dysfunction as a potential therapeutic target in people at increased risk of developing type 2 diabetes. PMID:27702832

Inhibition of NET Release Fails to Reduce Adipose Tissue Inflammation in Mice.

PubMed

Braster, Quinte; Silvestre Roig, Carlos; Hartwig, Helene; Beckers, Linda; den Toom, Myrthe; Döring, Yvonne; Daemen, Mat J; Lutgens, Esther; Soehnlein, Oliver

2016-01-01

Obesity-associated diseases such as Type 2 diabetes, liver disease and cardiovascular diseases are profoundly mediated by low-grade chronic inflammation of the adipose tissue. Recently, the importance of neutrophils and neutrophil-derived myeloperoxidase and neutrophil elastase on the induction of insulin resistance has been established. Since neutrophil elastase and myeloperoxidase are critically involved in the release of neutrophil extracellular traps (NETs), we here hypothesized that NETs may be relevant to early adipose tissue inflammation. Thus, we tested the effect of the Peptidyl Arginine Deiminase 4 inhibitor Cl-amidine, a compound preventing histone citrullination and subsequent NET release, in a mouse model of adipose tissue inflammation. C57BL6 mice received a 60% high fat diet for 10 weeks and were treated with either Cl-amidine or vehicle. Flow cytometry of adipose tissue and liver, immunohistological analysis and glucose and insulin tolerance tests were performed to determine the effect of the treatment and diet. Although high fat diet feeding induced insulin resistance no significant effect was observed between the treatment groups. In addition no effect was found in leukocyte infiltration and activation in the adipose tissue and liver. Therefore we concluded that inhibition of neutrophil extracellular trap formation may have no clinical relevance for early obesity-mediated pathogenesis of the adipose tissue and liver.

The ubiquitin ligase Siah2 regulates obesity-induced adipose tissue inflammation.

PubMed

Kilroy, Gail; Carter, Lauren E; Newman, Susan; Burk, David H; Manuel, Justin; Möller, Andreas; Bowtell, David D; Mynatt, Randall L; Ghosh, Sujoy; Floyd, Z Elizabeth

2015-11-01

Chronic, low-grade adipose tissue inflammation associated with adipocyte hypertrophy is an important link in the relationship between obesity and insulin resistance. Although ubiquitin ligases regulate inflammatory processes, the role of these enzymes in metabolically driven adipose tissue inflammation is relatively unexplored. Herein, the effect of the ubiquitin ligase Siah2 on obesity-related adipose tissue inflammation was examined. Wild-type and Siah2KO mice were fed a low- or high-fat diet for 16 weeks. Indirect calorimetry, body composition, and glucose and insulin tolerance were assayed along with glucose and insulin levels. Gene and protein expression, immunohistochemistry, adipocyte size distribution, and lipolysis were also analyzed. Enlarged adipocytes in obese Siah2KO mice were not associated with obesity-induced insulin resistance. Proinflammatory gene expression, stress kinase signaling, fibrosis, and crown-like structures were reduced in the Siah2KO adipose tissue, and Siah2KO adipocytes were more responsive to insulin-dependent inhibition of lipolysis. Loss of Siah2 increased expression of PPARγ target genes involved in lipid metabolism and decreased expression of proinflammatory adipokines regulated by PPARγ. Siah2 links adipocyte hypertrophy with adipocyte dysfunction and recruitment of proinflammatory immune cells to adipose tissue. Selective regulation of PPARγ activity is a Siah2-mediated mechanism contributing to obesity-induced adipose tissue inflammation. © 2015 The Obesity Society.

Human immunodeficiency virus atropy induces modification of subcutaneous adipose tissue architecture: in vivo visualization by high-resolution magnetic resonance imaging.

PubMed

Josse, G; Gensanne, D; Aquilina, C; Bernard, J; Saint-Martory, C; Lagarde, J M; Schmitt, A M

2009-04-01

Human immunodeficiency virus (HIV) infection generally induces lipodystrophy. For targeted treatment a better understanding of its development is necessary. The utility of high-resolution magnetic resonance imaging (MRI) is explored. The present study presents a way to visualize the adipose tissue architecture in vivo and to inspect modifications associated with the atrophy. High-resolution MRI scans with surface coils were performed on the calf and at the lumbar region of three groups of patients: HIV patients with lipoatrophy, HIV patients without lipoatrophy and healthy volunteers. All patients underwent a clinical examination. In addition, dual energy X-ray absorptiometry (DEXA) measurements were taken. On the MRI scans adipose tissue thickness and adipose nodule size were measured. Results High-resolution MRI enabled identification of a clear disorganization of adipose tissue in patients with lipoatrophy. In addition, these patients presented a very small adipose tissue thickness on the calf and a very small nodule size. led to the hypothesis that adipose tissue disorganization appears before changes in DEXA measurements or clinically visible modifications. High-resolution MRI enabled visualization in vivo of precise changes in tissue organization due to HIV lipoatrophy. This imaging technique should be very informative for better monitoring of the atrophy.

Short-term oleoyl-estrone treatment affects capacity to manage lipids in rat adipose tissue

PubMed Central

Salas, Anna; Noé, Véronique; Ciudad, Carlos J; Romero, M Mar; Remesar, Xavier; Esteve, Montserrat

2007-01-01

Background Short-term OE (oleoyl-estrone) treatment causes significant decreases in rat weight mainly due to adipose tissue loss. The aim of this work was to determine if OE treatment affects the expression of genes that regulate lipid metabolism in white adipose tissue. Results Gene expression in adipose tissue from female treated rats (48 hours) was analysed by hybridization to cDNA arrays and levels of specific mRNAs were determined by real-time PCR. Treatment with OE decreased the expression of 232 genes and up-regulated 75 other genes in mesenteric white adipose tissue. The use of real-time PCR validate that, in mesenteric white adipose tissue, mRNA levels for Lipoprotein Lipase (LPL) were decreased by 52%, those of Fatty Acid Synthase (FAS) by 95%, those of Hormone Sensible Lipase (HSL) by 32%, those of Acetyl CoA Carboxylase (ACC) by 92%, those of Carnitine Palmitoyltransferase 1b (CPT1b) by 45%, and those of Fatty Acid Transport Protein 1 (FATP1) and Adipocyte Fatty Acid Binding Protein (FABP4) by 52% and 49%, respectively. Conversely, Tumour Necrosis Factor (TNFα) values showed overexpression (198%). Conclusion Short-term treatment with OE affects adipose tissue capacity to extract fatty acids from lipoproteins and to deal with fatty acid transport and metabolism. PMID:17725831

Short-term oleoyl-estrone treatment affects capacity to manage lipids in rat adipose tissue.

PubMed

Salas, Anna; Noé, Véronique; Ciudad, Carlos J; Romero, M Mar; Remesar, Xavier; Esteve, Montserrat

2007-08-28

Short-term OE (oleoyl-estrone) treatment causes significant decreases in rat weight mainly due to adipose tissue loss. The aim of this work was to determine if OE treatment affects the expression of genes that regulate lipid metabolism in white adipose tissue. Gene expression in adipose tissue from female treated rats (48 hours) was analysed by hybridization to cDNA arrays and levels of specific mRNAs were determined by real-time PCR. Treatment with OE decreased the expression of 232 genes and up-regulated 75 other genes in mesenteric white adipose tissue. The use of real-time PCR validate that, in mesenteric white adipose tissue, mRNA levels for Lipoprotein Lipase (LPL) were decreased by 52%, those of Fatty Acid Synthase (FAS) by 95%, those of Hormone Sensible Lipase (HSL) by 32%, those of Acetyl CoA Carboxylase (ACC) by 92%, those of Carnitine Palmitoyltransferase 1b (CPT1b) by 45%, and those of Fatty Acid Transport Protein 1 (FATP1) and Adipocyte Fatty Acid Binding Protein (FABP4) by 52% and 49%, respectively. Conversely, Tumour Necrosis Factor (TNFalpha) values showed overexpression (198%). Short-term treatment with OE affects adipose tissue capacity to extract fatty acids from lipoproteins and to deal with fatty acid transport and metabolism.

Monitoring of temperature-mediated phase transitions of adipose tissue by combined optical coherence tomography and Abbe refractometry.

PubMed

Yanina, Irina Y; Popov, Alexey P; Bykov, Alexander V; Meglinski, Igor V; Tuchin, Valery V

2018-01-01

Observation of temperature-mediated phase transitions between lipid components of the adipose tissues has been performed by combined use of the Abbe refractometry and optical coherence tomography. The phase transitions of the lipid components were clearly observed in the range of temperatures from 24°C to 60°C, and assessed by quantitatively monitoring the changes of the refractive index of 1- to 2-mm-thick porcine fat tissue slices. The developed approach has a great potential as an alternative method for obtaining accurate information on the processes occurring during thermal lipolysis. (2018) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE).

Preliminary results comparing the recovery of basic fibroblast growth factor (FGF-2) in adipose tissue and benign and malignant renal tissue.

PubMed

Mydlo, J H; Kral, J G; Macchia, R J

1998-06-01

Basic fibroblast growth factor (bFGF or FGF-2) is mitogenic to numerous epithelial, mesodermal and endothelial cells, and thus may play a role in the neovascularity and progression of several tumors. Furthermore, FGF-2 is reported to be elevated in the serum and urine of patients with various cancers, including renal cancer. Obesity, with increased body fat, is a risk factor for renal cancer through unknown mechanisms. Since adipose tissue is a source of FGF-2, we determined the quantity and quality of activity of FGF-2 in omental adipose tissue and compared it to normal and cancerous renal tissue. Using heparin-Sepharose chromatography we extracted proteins from human omental adipose tissue, renal cell carcinoma (RCC) and benign renal tissue (BRT). Using FGF-2 antisera we performed western blot analysis to confirm their homology to FGF-2. We also assessed recovery, mitogenicity and angiogenicity of each of the proteins using thymidine incorporation into human umbilical vein endothelial cells (HUVEC) and the chorioallantoic membrane (CAM) assay. Each of the three purified mitogenic proteins eluted with NaCl concentrations between 1.4 M. and 1.8 M., similar to control FGF-2. There was greater recovery of FGF-2 from omental adipose tissue compared with renal cell carcinoma or benign renal tissue (42 microg. vs. 24 microg. and 18 microg., respectively; ANOVA p <0.05). Moreover, FGF-2 from adipose tissue had greater mitogenic activity (96.% versus 68% and 38%; p <0.05) and greater angiogenic activity (5.5 vessels versus 2.7 and 1.6 vessels; p <0.05) on the CAM assay. We suggest that human omental adipose tissue FGF-2 may demonstrate greater mitogenic and angiogenic activity than either benign or cancerous renal tissue FGF-2. It is not known if FGF-2 from adipose tissue may play a role in the relationship between obesity and renal cancer.

Direct comparison of progenitor cells derived from adipose, muscle, and bone marrow from wild-type or craniosynostotic rabbits

PubMed Central

GM, Cooper; EL, Lensie; JJ, Cray; MR, Bykowski; GE, DeCesare; MA, Smalley; MP, Mooney; PG, Campbell; JE, Losee

2010-01-01

Background Reports have identified cells capable of osteogenic differentiation in bone marrow, muscle, and adipose tissues, but there are few direct comparisons of these different cell-types. Also, few have investigated the potential connection between a tissue-specific pathology and cells derived from seemingly unrelated tissues. Here, we compare cells isolated from wild-type rabbits or rabbits with nonsyndromic craniosynostosis, defined as the premature fusion of one or more of the cranial sutures. Methods Cells were derived from bone marrow, adipose, and muscle of 10 day-old wild-type rabbits (WT; n=17) or from age-matched rabbits with familial nonsyndromic craniosynostosis (CS; n=18). Cells were stimulated with bone morphogenetic protein 4 (BMP4) and alkaline phosphatase expression and cell proliferation were assessed. Results In WT rabbits, cells derived from muscle had more alkaline phosphatase activity than cells derived from either adipose or bone marrow. The cells derived from CS rabbit bone marrow and muscle were significantly more osteogenic than WT. Adipose-derived cells demonstrated no significant differences. While muscle-derived cells were most osteogenic in WT rabbits, bone marrow-derived cells were most osteogenic in CS rabbits. Conclusions Results suggest that cells from different tissues have different potentials for differentiation. Furthermore, cells derived from rabbits with craniosynostosis were different from wild-type derived cells. Interestingly, cells derived from the craniosynostotic rabbits were not uniformly more responsive compared with wild-type cells, suggesting that specific tissue-derived cells may react differently in individuals with craniosynostosis. PMID:20871482

Synthesis, radiosynthesis and in vitro evaluation of 18F-Bodipy-C16/triglyceride as a dual modal imaging agent for brown adipose tissue

PubMed Central

Maenen, Marco; Drude, Natascha; Nascimento, Emmani B. M.; van Marken Lichtenbelt, Wouter D.; Mottaghy, Felix M.; Bauwens, Matthias

2017-01-01

Background Brown adipose tissue research is in the focus in the field of endocrinology. We designed a dual-modal fluorescent/PET fatty acid based tracer on commercially available Bodipy-C16, which can be synthesized to its corresponding triglyceride and which combines the benefits of fluorescent and PET imaging. Methods Bodipy-C16 was coupled to 1,3-diolein resulting in Bodipy-triglyceride. Bodipy-C16 and Bodipy-triglyceride compounds were radiolabeled with 18F using an 18F/19F exchange reaction to yield a dual-modal imaging molecule. Uptake of radiolabeled and non-labeled Bodipy-C16 and Bodipy-triglyceride was analyzed by fluorescence imaging and radioactive uptake in cultured adipocytes derived from human brown adipose tissue and white adipose tissue. Results Bodipy-C16 and Bodipy-triglyceride were successfully radiolabeled and Bodipy-C16 showed high shelf life and blood plasma stability (99% from 0–4 h). The uptake of Bodipy-C16 increased over time in cultured adipocytes, which was further enhanced after beta-adrenergic stimulation with norepinephrine. The uptake of Bodipy-C16 was inhibited by oleic acid and CD36 inhibitor sulfosuccinimidyl-oleate. The poor solubility of Bodipy-triglyceride did not allow stability or in vitro experiments. Conclusion The new developed dual modal fatty acid based tracers Bodipy-C16 and Bodipy-triglyceride showed promising results to stimulate further in vivo evaluation and will help to understand brown adipose tissues role in whole body energy expenditure. PMID:28817670

Adipose-derived stem cells for cartilage regeneration - moving towards clinical applicability

PubMed Central

2013-01-01

Despite multiple methods of treatment and a wealth of research in the field of regenerative medicine focusing on cartilage defects, the management of cartilage injuries remains a challenge. A recent study by Van Pham and colleagues proposes a method for preconditioning autologous adipose-derived stem cells. Their study offers evidence about the increased proliferative and chondrogenetic capabilities of platelet-rich plasma-treated adipose-derived stem cells and the increased efficiency of these in treating articular cartilage defects in mice. Even though the method needs further elaboration and the composition of the repair tissue requires investigation, the results are promising for the design of clinically acceptable cell therapies aimed at cartilage regeneration. PMID:24079605

Early postnatal maternal separation causes alterations in the expression of β3-adrenergic receptor in rat adipose tissue suggesting long-term influence on obesity

DOE Office of Scientific and Technical Information (OSTI.GOV)

Miki, Takanori, E-mail: mikit@med.kagawa-u.ac.jp; Liu, Jun-Qian; Ohta, Ken-ichi

Highlights: •High-fat diet intake following maternal separation did not cause body weight gain. •However, levels of metabolism-related molecules in adipose tissue were altered. •Increased levels of prohibitin mRNA in white fat were observed. •Attenuated levels of β3-adrenergic receptor mRNA were observed in brown fat. •Such alterations in adipose tissue may contribute to obesity later in life. -- Abstract: The effects of early postnatal maternal deprivation on the biological characteristics of the adipose tissue later in life were investigated in the present study. Sprague–Dawley rats were classified as either maternal deprivation (MD) or mother-reared control (MRC) groups. MD was achieved bymore » separating the rat pups from their mothers for 3 h each day during the 10–15 postnatal days. mRNA levels of mitochondrial uncoupling protein 1 (UCP-1), β3-adrenergic receptor (β3-AR), and prohibitin (PHB) in the brown and white adipose tissue were determined using real-time RT-PCR analysis. UCP-1, which is mediated through β3-AR, is closely involved in the energy metabolism and expenditure. PHB is highly expressed in the proliferating tissues/cells. At 10 weeks of age, the body weight of the MRC and MD rats was similar. However, the levels of the key molecules in the adipose tissue were substantially altered. There was a significant increase in the expression of PHB mRNA in the white adipose tissue, while the β3-AR mRNA expression decreased significantly, and the UCP-1 mRNA expression remained unchanged in the brown adipose tissue. Given that these molecules influence the mitochondrial metabolism, our study indicates that early postnatal maternal deprivation can influence the fate of adipose tissue proliferation, presumably leading to obesity later in life.« less

Inhibition of thrombin action ameliorates insulin resistance in type 2 diabetic db/db mice.

PubMed

Mihara, Masatomo; Aihara, Ken-ichi; Ikeda, Yasumasa; Yoshida, Sumiko; Kinouchi, Mizuho; Kurahashi, Kiyoe; Fujinaka, Yuichi; Akaike, Masashi; Matsumoto, Toshio

2010-02-01

The binding of thrombin to its receptor stimulates inflammatory cytokines including IL-6 and monocyte chemoattractant protein-1 (MCP-1); both are associated with the development of insulin resistance. Because increased adiposity enhanced the expression of coagulation factor VII that stimulates the coagulation pathway in adipose tissue, we tested whether the inhibition of thrombin action ameliorates insulin resistance in obese diabetic (Lpr(-/-):db/db) mice. The 4-wk administration of argatroban, a selective thrombin inhibitor, reduced fasting plasma glucose and ameliorated insulin resistance in these mice. It also reduced adipocyte size and macrophage infiltration into adipose tissue. The aberrant gene expression of MCP-1, IL-6, adiponectin, and factor VII and suppressed insulin receptor substrate-1-Akt signaling in adipose tissue of db/db mice were reversed by argatroban treatment. These results demonstrate that increased adiposity enhances the production of thrombin in adipose tissue by stimulating factor VII expression and suggest that increased thrombin activity in adipose tissue plays an important role in the development of insulin resistance via enhancing MCP-1 production, leading to macrophage infiltration and insulin receptor substrate-1-Akt pathway inactivation.

Caveolin-1 Deficiency Leads to Increased Susceptibility to Cell Death and Fibrosis in White Adipose Tissue: Characterization of a Lipodystrophic Model

PubMed Central

Stanley, Amanda C.; Bastiani, Michele; Okano, Satomi; Nixon, Susan J.; Thomas, Gethin; Stow, Jennifer L.; Parton, Robert G.

2012-01-01

Caveolin-1 (CAV1) is an important regulator of adipose tissue homeostasis. In the present study we examined the impact of CAV1 deficiency on the properties of mouse adipose tissue both in vivo and in explant cultures during conditions of metabolic stress. In CAV1−/− mice fasting caused loss of adipose tissue mass despite a lack of hormone-sensitive lipase (HSL) phosphorylation. In addition, fasting resulted in increased macrophage infiltration, enhanced deposition of collagen, and a reduction in the level of the lipid droplet protein perilipin A (PLIN1a). Explant cultures of CAV1−/− adipose tissue also showed a loss of PLIN1a during culture, enhanced secretion of IL-6, increased release of lactate dehydrogenase, and demonstrated increased susceptibility to cell death upon collagenase treatment. Attenuated PKA-mediated signaling to HSL, loss of PLIN1a and increased secretion of IL-6 were also observed in adipose tissue explants of CAV1+/+ mice with diet-induced obesity. Together these results suggest that while alterations in adipocyte lipid droplet biology support adipose tissue metabolism in the absence of PKA-mediated pro-lipolytic signaling in CAV1−/− mice, the tissue is intrinsically unstable resulting in increased susceptibility to cell death, which we suggest underlies the development of fibrosis and inflammation during periods of metabolic stress. PMID:23049990

Comparison of labeled acetate and glucose incorporations into lipids in the liver and adipose tissue after intravenous injection in rats.

PubMed

Iritani, Nobuko; Hirakawa, Tomoe; Fukuda, Hitomi; Katsukawa, Michiko; Kouno, Mika

2014-01-01

To compare incorporations of acetate and glucose in tissue total lipids and triacylglycerols (TAG), incorporations of labeled acetate and glucose in livers and epididymal adipose tissues (adipose tissue) were followed after their intravenous injection in the tail vein of individual rat fed a fat-free or 10% corn oil diet. The incorporation of acetate into total lipids (mostly TAG) in the liver reached maximum 2 h after the injection, while the incorporation of glucose decreased more quickly. Incorporation of glucose into total lipids and TAG was more greatly suppressed by dietary corn oil than that of acetate in the liver. In the adipose tissues, the incorporation of labeled acetate or glucose into total lipids was maximum 2-8 h after the injection, while the incorporation of glucose was very low, especially in rats fed the corn oil diet. Moreover, the time courses for labeled acetate and glucose incorporations into total lipids in the liver were parallel to those in plasma, but opposite to those in adipose tissue. TAG synthesized from acetate and glucose in the liver appeared to be mostly transported to adipose tissue. Thus, it is suggested that as the labeled glucose rapidly decreased in the liver, plasma and adipose tissue, TAG should be less derived from dietary carbohydrate than from dietary fat.

A registration-based segmentation method with application to adiposity analysis of mice microCT images

NASA Astrophysics Data System (ADS)

Bai, Bing; Joshi, Anand; Brandhorst, Sebastian; Longo, Valter D.; Conti, Peter S.; Leahy, Richard M.

2014-04-01

Obesity is a global health problem, particularly in the U.S. where one third of adults are obese. A reliable and accurate method of quantifying obesity is necessary. Visceral adipose tissue (VAT) and subcutaneous adipose tissue (SAT) are two measures of obesity that reflect different associated health risks, but accurate measurements in humans or rodent models are difficult. In this paper we present an automatic, registration-based segmentation method for mouse adiposity studies using microCT images. We co-register the subject CT image and a mouse CT atlas. Our method is based on surface matching of the microCT image and an atlas. Surface-based elastic volume warping is used to match the internal anatomy. We acquired a whole body scan of a C57BL6/J mouse injected with contrast agent using microCT and created a whole body mouse atlas by manually delineate the boundaries of the mouse and major organs. For method verification we scanned a C57BL6/J mouse from the base of the skull to the distal tibia. We registered the obtained mouse CT image to our atlas. Preliminary results show that we can warp the atlas image to match the posture and shape of the subject CT image, which has significant differences from the atlas. We plan to use this software tool in longitudinal obesity studies using mouse models.

Cross Talk between Adipose Tissue and Placenta in Obese and Gestational Diabetes Mellitus Pregnancies via Exosomes.

PubMed

Jayabalan, Nanthini; Nair, Soumyalekshmi; Nuzhat, Zarin; Rice, Gregory E; Zuñiga, Felipe A; Sobrevia, Luis; Leiva, Andrea; Sanhueza, Carlos; Gutiérrez, Jaime Agustín; Lappas, Martha; Freeman, Dilys Jane; Salomon, Carlos

2017-01-01

Obesity is an important public health issue worldwide, where it is commonly associated with the development of metabolic disorders, especially insulin resistance (IR). Maternal obesity is associated with an increased risk of pregnancy complications, especially gestational diabetes mellitus (GDM). Metabolism is a vital process for energy production and the maintenance of essential cellular functions. Excess energy storage is predominantly regulated by the adipose tissue. Primarily made up of adipocytes, adipose tissue acts as the body's major energy reservoir. The role of adipose tissue, however, is not restricted to a "bag of fat." The adipose tissue is an endocrine organ, secreting various adipokines, enzymes, growth factors, and hormones that take part in glucose and lipid metabolism. In obesity, the greater portion of the adipose tissue comprises fat, and there is increased pro-inflammatory cytokine secretion, macrophage infiltration, and reduced insulin sensitivity. Obesity contributes to systemic IR and its associated metabolic complications. Similar to adipose tissue, the placenta is also an endocrine organ. During pregnancy, the placenta secretes various molecules to maintain pregnancy physiology. In addition, the placenta plays an important role in metabolism and exchange of nutrients between mother and fetus. Inflammation at the placenta may contribute to the severity of maternal IR and her likelihood of developing GDM and may also mediate the adverse consequences of obesity and GDM on the fetus. Interestingly, studies on maternal insulin sensitivity and secretion of placental hormones have not shown a positive correlation between these phenomena. Recently, a great interest in the field of extracellular vesicles (EVs) has been observed in the literature. EVs are produced by a wide range of cells and are present in all biological fluids. EVs are involved in cell-to-cell communication. Recent evidence points to an association between adipose tissue-derived EVs and metabolic syndrome in obesity. In this review, we will discuss the changes in human placenta and adipose tissue in GDM and obesity and summarize the findings regarding the role of adipose tissue and placenta-derived EVs, with an emphasis on exosomes in obesity, and the contribution of obesity to the development of GDM.

Cross Talk between Adipose Tissue and Placenta in Obese and Gestational Diabetes Mellitus Pregnancies via Exosomes

PubMed Central

Jayabalan, Nanthini; Nair, Soumyalekshmi; Nuzhat, Zarin; Rice, Gregory E.; Zuñiga, Felipe A.; Sobrevia, Luis; Leiva, Andrea; Sanhueza, Carlos; Gutiérrez, Jaime Agustín; Lappas, Martha; Freeman, Dilys Jane; Salomon, Carlos

2017-01-01

Obesity is an important public health issue worldwide, where it is commonly associated with the development of metabolic disorders, especially insulin resistance (IR). Maternal obesity is associated with an increased risk of pregnancy complications, especially gestational diabetes mellitus (GDM). Metabolism is a vital process for energy production and the maintenance of essential cellular functions. Excess energy storage is predominantly regulated by the adipose tissue. Primarily made up of adipocytes, adipose tissue acts as the body’s major energy reservoir. The role of adipose tissue, however, is not restricted to a “bag of fat.” The adipose tissue is an endocrine organ, secreting various adipokines, enzymes, growth factors, and hormones that take part in glucose and lipid metabolism. In obesity, the greater portion of the adipose tissue comprises fat, and there is increased pro-inflammatory cytokine secretion, macrophage infiltration, and reduced insulin sensitivity. Obesity contributes to systemic IR and its associated metabolic complications. Similar to adipose tissue, the placenta is also an endocrine organ. During pregnancy, the placenta secretes various molecules to maintain pregnancy physiology. In addition, the placenta plays an important role in metabolism and exchange of nutrients between mother and fetus. Inflammation at the placenta may contribute to the severity of maternal IR and her likelihood of developing GDM and may also mediate the adverse consequences of obesity and GDM on the fetus. Interestingly, studies on maternal insulin sensitivity and secretion of placental hormones have not shown a positive correlation between these phenomena. Recently, a great interest in the field of extracellular vesicles (EVs) has been observed in the literature. EVs are produced by a wide range of cells and are present in all biological fluids. EVs are involved in cell-to-cell communication. Recent evidence points to an association between adipose tissue-derived EVs and metabolic syndrome in obesity. In this review, we will discuss the changes in human placenta and adipose tissue in GDM and obesity and summarize the findings regarding the role of adipose tissue and placenta-derived EVs, with an emphasis on exosomes in obesity, and the contribution of obesity to the development of GDM. PMID:29021781

Characterization of visceral and subcutaneous adipose tissue transcriptome in pregnant women with and without spontaneous labor at term: Implication of alternative splicing in the metabolic adaptations of adipose tissue to parturition

PubMed Central

Mazaki-Tovi, Shali; Tarca, Adi L.; Vaisbuch, Edi; Kusanovic, Juan Pedro; Than, Nandor Gabor; Chaiworapongsa, Tinnakorn; Dong, Zhong; Hassan, Sonia S; Romero, Roberto

2018-01-01

OBJECTIVE The aim of this study was to determine gene expression and splicing changes associated with parturition and regions (visceral vs subcutaneous) of the adipose tissue of pregnant women. STUDY DESIGN The transcriptome of visceral and abdominal subcutaneous adipose tissue from pregnant women at term with (n=15) and without (n=25) spontaneous labor was profiled with Affymetrix GeneChip Human Exon 1.0 ST array. Overall gene expression changes and differential exon usage rate were compared between patient groups and adipose tissue regions (paired analyses). Selected genes were tested by quantitative reverse transcription–polymerase chain reaction. RESULTS Four hundred eighty-two genes were differentially expressed between visceral and subcutaneous fat of pregnant women with spontaneous labor at term (q-value <0.1; fold change >1.5). Biological processes enriched in this comparison included tissue and vasculature development, inflammatory and metabolic pathways. Differential splicing was found for 42 genes (q-value <0.1; difference FIRMA scores >2) between adipose tissue regions of women not in labor. Differential exon usage associated with parturition was found for three genes (LIMS1, HSPA5 and GSTK1) in subcutaneous tissues. CONCLUSION We show for the first time evidence of implication of mRNA splicing and processing machinery in the subcutaneous adipose tissue of women in labor compared to those without labor. PMID:26994472

Characterization of visceral and subcutaneous adipose tissue transcriptome in pregnant women with and without spontaneous labor at term: implication of alternative splicing in the metabolic adaptations of adipose tissue to parturition.

PubMed

Mazaki-Tovi, Shali; Tarca, Adi L; Vaisbuch, Edi; Kusanovic, Juan Pedro; Than, Nandor Gabor; Chaiworapongsa, Tinnakorn; Dong, Zhong; Hassan, Sonia S; Romero, Roberto

2016-10-01

The aim of this study was to determine gene expression and splicing changes associated with parturition and regions (visceral vs. subcutaneous) of the adipose tissue of pregnant women. The transcriptome of visceral and abdominal subcutaneous adipose tissue from pregnant women at term with (n=15) and without (n=25) spontaneous labor was profiled with the Affymetrix GeneChip Human Exon 1.0 ST array. Overall gene expression changes and the differential exon usage rate were compared between patient groups (unpaired analyses) and adipose tissue regions (paired analyses). Selected genes were tested by quantitative reverse transcription-polymerase chain reaction. Four hundred and eighty-two genes were differentially expressed between visceral and subcutaneous fat of pregnant women with spontaneous labor at term (q-value <0.1; fold change >1.5). Biological processes enriched in this comparison included tissue and vasculature development as well as inflammatory and metabolic pathways. Differential splicing was found for 42 genes [q-value <0.1; differences in Finding Isoforms using Robust Multichip Analysis scores >2] between adipose tissue regions of women not in labor. Differential exon usage associated with parturition was found for three genes (LIMS1, HSPA5, and GSTK1) in subcutaneous tissues. We show for the first time evidence of implication of mRNA splicing and processing machinery in the subcutaneous adipose tissue of women in labor compared to those without labor.

An analysis of DNA methylation in human adipose tissue reveals differential modification of obesity genes before and after gastric bypass and weight loss.

PubMed

Benton, Miles C; Johnstone, Alice; Eccles, David; Harmon, Brennan; Hayes, Mark T; Lea, Rod A; Griffiths, Lyn; Hoffman, Eric P; Stubbs, Richard S; Macartney-Coxson, Donia

2015-01-22

Environmental factors can influence obesity by epigenetic mechanisms. Adipose tissue plays a key role in obesity-related metabolic dysfunction, and gastric bypass provides a model to investigate obesity and weight loss in humans. Here, we investigate DNA methylation in adipose tissue from obese women before and after gastric bypass and significant weight loss. In total, 485,577 CpG sites were profiled in matched, before and after weight loss, subcutaneous and omental adipose tissue. A paired analysis revealed significant differential methylation in omental and subcutaneous adipose tissue. A greater proportion of CpGs are hypermethylated before weight loss and increased methylation is observed in the 3' untranslated region and gene bodies relative to promoter regions. Differential methylation is found within genes associated with obesity, epigenetic regulation and development, such as CETP, FOXP2, HDAC4, DNMT3B, KCNQ1 and HOX clusters. We identify robust correlations between changes in methylation and clinical trait, including associations between fasting glucose and HDAC4, SLC37A3 and DENND1C in subcutaneous adipose. Genes investigated with differential promoter methylation all show significantly different levels of mRNA before and after gastric bypass. This is the first study reporting global DNA methylation profiling of adipose tissue before and after gastric bypass and associated weight loss. It provides a strong basis for future work and offers additional evidence for the role of DNA methylation of adipose tissue in obesity.

CELL BIOLOGY SYMPOSIUM: Practical application of the basic aspects of GLUT4 membrane trafficking and insulin signaling on issues related to animal agriculture.

PubMed

Smith, S B

2017-05-01

Because of the relatively short lifespans of beef cattle, membrane trafficking in relation to inflammation is not considered important unless it overtly affects productivity. However, glucose uptake and utilization is important for adipose tissue development in beef cattle, and increasing glucose utilization in intramuscular adipose tissue can increase carcass quality. Research from the 1980s demonstrated a lack of insulin sensitivity in isolated bovine adipocytes and adipose tissue explants incubated in vitro. Insulin did not stimulate glucose or acetate incorporation into fatty acids, nor did it increase concentrations of glycolytic intermediates in bovine adipose tissue incubated with exogenous glucose. Specific binding of [I] iodoinsulin and insulin degradation in bovine isolated adipocytes was low to non-detectable. These early studies indicated that insulin-dependent receptor-mediated signaling was less important in bovine adipose tissue than in adipose tissues of humans, swine, or laboratory species. More recent research demonstrated that glucose transporter protein 4 (GLUT4) expression in muscle and adipose tissue declines markedly after birth in calves, indicating the development of insulin resistance as cattle transition from suckling to functional ruminants. Insulin resistance is important in dairy cattle, causing ketosis and fatty liver. Consistent with this, subcutaneous adipose tissue expression decreases 50% following parturition in dairy cattle, although expression of genes associated with insulin responsiveness (, , and ) is up-regulated by 21 d postpartum. Understanding the underlying mechanisms of insulin resistance in beef and dairy cattle would increase animal health and thereby improve productivity.

Apoptosis inhibitor of macrophage (AIM) is required for obesity-associated recruitment of inflammatory macrophages into adipose tissue

PubMed Central

Kurokawa, Jun; Nagano, Hiromichi; Ohara, Osamu; Kubota, Naoto; Kadowaki, Takashi; Arai, Satoko; Miyazaki, Toru

2011-01-01

Infiltration of inflammatory macrophages into adipose tissues with the progression of obesity triggers insulin resistance and obesity-related metabolic diseases. We recently reported that macrophage-derived apoptosis inhibitor of macrophage (AIM) protein is increased in blood in line with obesity progression and is incorporated into adipocytes, thereby inducing lipolysis in adipose tissue. Here we show that such a response is required for the recruitment of adipose tissue macrophages. In vitro, AIM-dependent lipolysis induced an efflux of palmitic and stearic acids from 3T3-L1 adipocytes, thereby stimulating chemokine production in adipocytes via activation of toll-like receptor 4 (TLR4). In vivo administration of recombinant AIM to TLR4-deficient (TLR4−/−) mice resulted in induction of lipolysis without chemokine production in adipose tissues. Consistently, mRNA levels for the chemokines that affect macrophages were far lower in AIM-deficient (AIM−/−) than in wild-type (AIM+/+) obese adipose tissue. This reduction in chemokine production resulted in a marked prevention of inflammatory macrophage infiltration into adipose tissue in obese AIM−/− mice, although these mice showed more advanced obesity than AIM+/+ mice on a high-fat diet. Diminished macrophage infiltration resulted in decreased inflammation locally and systemically in obese AIM−/− mice, thereby protecting them from insulin resistance and glucose intolerance. These results indicate that the increase in blood AIM is a critical event for the initiation of macrophage recruitment into adipose tissue, which is followed by insulin resistance. Thus, AIM suppression might be therapeutically applicable for the prevention of obesity-related metabolic disorders. PMID:21730133

Fats, inflammation and insulin resistance: insights to the role of macrophage and T-cell accumulation in adipose tissue.

PubMed

Harford, Karen A; Reynolds, Clare M; McGillicuddy, Fiona C; Roche, Helen M

2011-11-01

High-fat diet-induced obesity is associated with a chronic state of low-grade inflammation, which pre-disposes to insulin resistance (IR), which can subsequently lead to type 2 diabetes mellitus. Macrophages represent a heterogeneous population of cells that are instrumental in initiating the innate immune response. Recent studies have shown that macrophages are key mediators of obesity-induced IR, with a progressive infiltration of macrophages into obese adipose tissue. These adipose tissue macrophages are referred to as classically activated (M1) macrophages. They release cytokines such as IL-1β, IL-6 and TNFα creating a pro-inflammatory environment that blocks adipocyte insulin action, contributing to the development of IR and type 2 diabetes mellitus. In lean individuals macrophages are in an alternatively activated (M2) state. M2 macrophages are involved in wound healing and immunoregulation. Wound-healing macrophages play a major role in tissue repair and homoeostasis, while immunoregulatory macrophages produce IL-10, an anti-inflammatory cytokine, which may protect against inflammation. The functional role of T-cell accumulation has recently been characterised in adipose tissue. Cytotoxic T-cells are effector T-cells and have been implicated in macrophage differentiation, activation and migration. Infiltration of cytotoxic T-cells into obese adipose tissue is thought to precede macrophage accumulation. T-cell-derived cytokines such as interferon γ promote the recruitment and activation of M1 macrophages augmenting adipose tissue inflammation and IR. Manipulating adipose tissue macrophages/T-cell activity and accumulation in vivo through dietary fat modification may attenuate adipose tissue inflammation, representing a therapeutic target for ameliorating obesity-induced IR.

Comparative study of adipose-derived stem cells and bone marrow-derived stem cells in similar microenvironmental conditions

DOE Office of Scientific and Technical Information (OSTI.GOV)

Guneta, Vipra; Tan, Nguan Soon; KK Research Centre, KK Women's and Children Hospital, 100 Bukit Timah Road, Singapore 229899

Mesenchymal stem cells (MSCs), which were first isolated from the bone marrow, are now being extracted from various other tissues in the body, including the adipose tissue. The current study presents systematic evidence of how the adipose tissue-derived stem cells (ASCs) and bone marrow-derived mesenchymal stem cells (Bm-MSCs) behave when cultured in specific pro-adipogenic microenvironments. The cells were first characterized and identified as MSCs in terms of their morphology, phenotypic expression, self-renewal capabilities and multi-lineage potential. Subsequently, the proliferation and gene expression profiles of the cell populations cultured on two-dimensional (2D) adipose tissue extracellular matrix (ECM)-coated tissue culture plastic (TCP)more » and in three-dimensional (3D) AlgiMatrix® microenvironments were analyzed. Overall, it was found that adipogenesis was triggered in both cell populations due to the presence of adipose tissue ECM. However, in 3D microenvironments, ASCs and Bm-MSCs were predisposed to the adipogenic and osteogenic lineages respectively. Overall, findings from this study will contribute to ongoing efforts in adipose tissue engineering as well as provide new insights into the role of the ECM and cues provided by the immediate microenvironment for stem cell differentiation. - Highlights: • Native adipose tissue ECM coated on 2D TCP triggers adipogenesis in both ASCs and Bm-MSCs. • A 3D microenvironment with similar stiffness to adipose tissue induces adipogenic differentiation of ASCs. • ASCs cultured in 3D alginate scaffolds exhibit predisposition to adipogenesis. • Bm-MSCs cultured in 3D alginate scaffolds exhibit predisposition to osteogenesis. • The native microenvironment of the cells affects their differentiation behaviour in vitro.« less

Automated unsupervised multi-parametric classification of adipose tissue depots in skeletal muscle

PubMed Central

Valentinitsch, Alexander; Karampinos, Dimitrios C.; Alizai, Hamza; Subburaj, Karupppasamy; Kumar, Deepak; Link, Thomas M.; Majumdar, Sharmila

2012-01-01

Purpose To introduce and validate an automated unsupervised multi-parametric method for segmentation of the subcutaneous fat and muscle regions in order to determine subcutaneous adipose tissue (SAT) and intermuscular adipose tissue (IMAT) areas based on data from a quantitative chemical shift-based water-fat separation approach. Materials and Methods Unsupervised standard k-means clustering was employed to define sets of similar features (k = 2) within the whole multi-modal image after the water-fat separation. The automated image processing chain was composed of three primary stages including tissue, muscle and bone region segmentation. The algorithm was applied on calf and thigh datasets to compute SAT and IMAT areas and was compared to a manual segmentation. Results The IMAT area using the automatic segmentation had excellent agreement with the IMAT area using the manual segmentation for all the cases in the thigh (R2: 0.96) and for cases with up to moderate IMAT area in the calf (R2: 0.92). The group with the highest grade of muscle fat infiltration in the calf had the highest error in the inner SAT contour calculation. Conclusion The proposed multi-parametric segmentation approach combined with quantitative water-fat imaging provides an accurate and reliable method for an automated calculation of the SAT and IMAT areas reducing considerably the total post-processing time. PMID:23097409

Flaxseed Oil Alleviates Chronic HFD-Induced Insulin Resistance through Remodeling Lipid Homeostasis in Obese Adipose Tissue.

PubMed

Yu, Xiao; Tang, Yuhan; Liu, Peiyi; Xiao, Lin; Liu, Liegang; Shen, Ruiling; Deng, Qianchun; Yao, Ping

2017-11-08

Emerging evidence suggests that higher circulating long-chain n-3 polyunsaturated fatty acids (n-3PUFA) levels were intimately associated with lower prevalence of obesity and insulin resistance. However, the understanding of bioactivity and potential mechanism of α-linolenic acid-rich flaxseed oil (ALA-FO) against insulin resistance was still limited. This study evaluated the effect of FO on high-fat diet (HFD)-induced insulin resistance in C57BL/6J mice focused on adipose tissue lipolysis. Mice after HFD feeding for 16 weeks (60% fat-derived calories) exhibited systemic insulin resistance, which was greatly attenuated by medium dose of FO (M-FO), paralleling with differential accumulation of ALA and its n-3 derivatives across serum lipid fractions. Moreover, M-FO was sufficient to effectively block the metabolic activation of adipose tissue macrophages (ATMs), thereby improving adipose tissue insulin signaling. Importantly, suppression of hypoxia-inducible factors HIF-1α and HIF-2α were involved in FO-mediated modulation of adipose tissue lipolysis, accompanied by specific reconstitution of n-3PUFA within adipose tissue lipid fractions.

Biology and function of adipose tissue macrophages, dendritic cells and B cells.

PubMed

Ivanov, Stoyan; Merlin, Johanna; Lee, Man Kit Sam; Murphy, Andrew J; Guinamard, Rodolphe R

2018-04-01

The increasing incidence of obesity and its socio-economical impact is a global health issue due to its associated co-morbidities, namely diabetes and cardiovascular disease [1-5]. Obesity is characterized by an increase in adipose tissue, which promotes the recruitment of immune cells resulting in low-grade inflammation and dysfunctional metabolism. Macrophages are the most abundant immune cells in the adipose tissue of mice and humans. The adipose tissue also contains other myeloid cells (dendritic cells (DC) and neutrophils) and to a lesser extent lymphocyte populations, including T cells, B cells, Natural Killer (NK) and Natural Killer T (NKT) cells. While the majority of studies have linked adipose tissue macrophages (ATM) to the development of low-grade inflammation and co-morbidities associated with obesity, emerging evidence suggests for a role of other immune cells within the adipose tissue that may act in part by supporting macrophage homeostasis. In this review, we summarize the current knowledge of the functions ATMs, DCs and B cells possess during steady-state and obesity. Copyright © 2018 Elsevier B.V. All rights reserved.

Adipose tissue and breast epithelial cells: a dangerous dynamic duo in breast cancer.

PubMed

Wang, Yuan-Yuan; Lehuédé, Camille; Laurent, Victor; Dirat, Béatrice; Dauvillier, Stéphanie; Bochet, Ludivine; Le Gonidec, Sophie; Escourrou, Ghislaine; Valet, Philippe; Muller, Catherine

2012-11-28

Among the many different cell types surrounding breast cancer cells, the most abundant are those that compose mammary adipose tissue, mainly mature adipocytes and progenitors. New accumulating recent evidences bring the tumor-surrounding adipose tissue into the light as a key component of breast cancer progression. The purpose of this review is to emphasize the role that adipose tissue might play by locally affecting breast cancer cell behavior and subsequent clinical consequences arising from this dialog. Two particular clinical aspects are addressed: obesity that was identified as an independent negative prognostic factor in breast cancer and the oncological safety of autologous fat transfer used in reconstructive surgery for breast cancer patients. This is preceded by the overall description of adipose tissue composition and function with special emphasis on the specificity of adipose depots and the species differences, key experimental aspects that need to be taken in account when cancer is considered. Copyright © 2012 Elsevier Ireland Ltd. All rights reserved.

N-3 Polyunsaturated Fatty Acids of Marine Origin and Multifocality in Human Breast Cancer.

PubMed

Ouldamer, Lobna; Goupille, Caroline; Vildé, Anne; Arbion, Flavie; Body, Gilles; Chevalier, Stephan; Cottier, Jean Philippe; Bougnoux, Philippe

2016-01-01

The microenvironment of breast epithelial tissue may contribute to the clinical expression of breast cancer. Breast epithelial tissue, whether healthy or tumoral, is directly in contact with fat cells, which in turn could influence tumor multifocality. In this pilot study we investigated whether the fatty acid composition of breast adipose tissue differed according to breast cancer focality. Twenty-three consecutive women presenting with non-metastatic breast cancer underwent breast-imaging procedures including Magnetic Resonance Imaging prior to treatment. Breast adipose tissue specimens were collected during breast surgery. We established a biochemical profile of adipose tissue fatty acids by gas chromatography. We assessed whether there were differences according to breast cancer focality. We found that decreased levels in breast adipose tissue of docosahexaenoic and eicosapentaenoic acids, the two main polyunsaturated n-3 fatty acids of marine origin, were associated with multifocality. These differences in lipid content may contribute to mechanisms through which peritumoral adipose tissue fuels breast cancer multifocality.

Assessment of Regenerative Capacity in the Dolphin

DTIC Science & Technology

2010-10-10

liposuction ; cells released during the digestion of the adipose tissue were analyzed for cytology, assayed for the total number of colony-forming cells... liposuction was used to harvest subcutaneous adipose from the nuchal pad of six dolphins at the Navy Marine Mammal Program (NMMP). Adipose samples...and aid in the placement of the liposuction cannula in the adipose depot. The difference between the various layers of muscle and adipose tissue

Fatty Acid Composition of Lamb Liver, Muscle, And Adipose Tissues in Response to Rumen-Protected Conjugated Linoleic Acid (CLA) Supplementation Is Tissue Dependent.

PubMed

Schiavon, Stefano; Bergamaschi, Matteo; Pellattiero, Erika; Simonetto, Alberto; Tagliapietra, Franco

2017-12-06

The tissue-specific response to rumen-protected conjugated linoleic acid supply (rpCLA) of liver, two muscles, and three adipose tissues of heavy lambs was studied. Twenty-four lambs, 8 months old, divided into 4 groups of 6, were fed at libitum on a ration supplemented without or with a mixture of rpCLA. Silica and hydrogenated soybean oil was the rpCLA coating matrix. The lambs were slaughtered at 11 months of age. Tissues were collected and analyzed for their FA profiles. The dietary rpCLA supplement had no influence on carcass fatness nor on the fat content of the liver and tissues and had little influence on the FA profiles of these tissues. In the adipose tissues, rpCLA increased the proportions of saturated FAs, 18:0 and 18:2t10c12, and decreased the proportions of monounsaturated FAs in the adipose tissues. In muscles, the effects were the opposite. The results suggest that Δ9 desaturase activity is inhibited by the rpCLA mixture in adipose tissues to a greater extent than in the other tissues.

Roles of Perivascular Adipose Tissue in the Pathogenesis of Atherosclerosis

PubMed Central

Tanaka, Kimie; Sata, Masataka

2018-01-01

Traditionally, it is believed that white adipose tissues serve as energy storage, heat insulation, and mechanical cushion, whereas non-shivering thermogenesis occurs in brown adipose tissue. Recent evidence revealed that adipose tissue secretes many types of cytokines, called as adipocytokines, which modulate glucose metabolism, lipid profile, appetite, fibrinolysis, blood pressure, and inflammation. Most of the arteries are surrounded by perivascular adipose tissue (PVAT). PVAT has been thought to be simply a structurally supportive tissue for vasculature. However, recent studies showed that PVAT influences vasodilation and vasocontraction, suggesting that PVAT regulates vascular tone and diameter. Adipocytokines secreted from PVAT appear to have direct access to the adjacent arterial wall by diffusion or via vasa vasorum. In fact, PVAT around atherosclerotic lesions and mechanically-injured arteries displayed inflammatory cytokine profiles, suggesting that PVAT functions to promote vascular lesion formation. Many clinical studies revealed that increased accumulation of epicardial adipose tissue (EAT), which surrounds coronary arteries, is associated with coronary artery disease. In this review article, we will summarize recent findings about potential roles of PVAT in the pathogenesis of atherosclerosis, particularly focusing on a series of basic and clinical studies from our laboratory. PMID:29487532

Correlation of MRI-derived adipose tissue measurements and anthropometric markers with prevalent hypertension in the community.

PubMed

Lorbeer, Roberto; Rospleszcz, Susanne; Schlett, Christopher L; Heber, Sophia D; Machann, Jürgen; Thorand, Barbara; Meisinger, Christa; Heier, Margit; Peters, Annette; Bamberg, Fabian; Lieb, Wolfgang

2018-07-01

To compare the correlations of MRI-derived adipose tissue measurements and anthropometric markers, respectively, with prevalent hypertension in a community-based sample, free of clinical cardiovascular disease. MRI-derived adipose tissue measurements were obtained in 345 participants (143 women; age 39-73 years) of the KORA FF4 survey from Southern Germany using a 3-Tesla machine and included total adipose tissue (TAT), visceral adipose tissue (VAT), subcutaneous adipose tissue (SCAT), hepatic fat fraction (HFF), pancreatic fat fraction (PFF) as well as pericardial adipose tissue (PAT). In addition, the anthropometric markers body mass index, waist circumference, hip circumference, waist-hip ratio (WHR) and waist-height ratio (WHtR) as well as blood pressure measurements were obtained. The prevalence of hypertension was 33.6% (women: 28%, men: 38%). VAT and PAT had the highest area under the curve (AUC) values for identifying individuals with prevalent hypertension (AUC: 0.75; 0.73, respectively), whereas WHtR and waist circumference were best performing anthropometric markers (AUC: 0.72; 0.70, respectively). A 1SD increment of TAT was associated with the highest odd for hypertension in the age-adjusted and sex-adjusted model (OR = 2.20, 95% CI 1.67-2.91, P < 0.001) and in the fully adjusted model (OR = 1.97, 95% CI 1.45-2.66, P < 0.001). TAT was the only MRI-derived adipose tissue measurement that was associated with hypertension independently of the best performing anthropometric marker waist circumference in the fully adjusted model (OR = 1.93, 95% CI 1.00-3.72, P = 0.049). MRI-derived adipose tissue measurements perform similarly in identifying prevalent hypertension compared with anthropometric markers. Especially, TAT, VAT and PAT as well as WHtR and waist circumference were highly correlated with prevalent hypertension.

Depot differences in steroid receptor expression in adipose tissue: possible role of the local steroid milieu.

PubMed

Rodriguez-Cuenca, S; Monjo, M; Proenza, A M; Roca, P

2005-01-01

Sex hormones play an important role in adipose tissue metabolism by activating specific receptors that alter several steps of the lipolytic and lipogenic signal cascade in depot- and sex-dependent manners. However, studies focusing on steroid receptor status in adipose tissue are scarce. In the present study, we analyzed steroid content [testosterone (T), 17beta-estradiol (17beta-E2), and progesterone (P4)] and steroid receptor mRNA levels in different rat adipose tissue depots. As expected, T levels were higher in males than in females (P = 0.031), whereas the reverse trend was observed for P4 (P < 0.001). It is noteworthy that 17beta-E2 adipose tissue levels were higher in inguinal than in the rest of adipose tissues for both sexes, where no sex differences in 17beta-E2 tissue levels were noted (P = 0.010 for retroperitoneal, P = 0.005 for gonadal, P = 0.018 for mesenteric). Regarding steroid receptor levels, androgen (AR) and estrogen receptor (ER)alpha and ERbeta densities were more clearly dependent on adipose depot location than on sex, with visceral depots showing overall higher mRNA densities than their subcutaneous counterparts. Besides, expression of ERalpha predominated over ERbeta expression, and progesterone receptor (PR-B form and PR-A+B form) mRNAs were identically expressed regardless of anatomic depot and sex. In vitro studies in 3T3-L1 cells showed that 17beta-E2 increased ERalpha (P = 0.001) and AR expression (P = 0.001), indicating that estrogen can alter estrogenic and androgenic signaling in adipose tissue. The results highlighted in this study demonstrate important depot-dependent differences in the sensitivity of adipose tissues to sex hormones between visceral and subcutaneous depots that could be related to metabolic situations observed in response to sex hormones.

Adipose tissue CIDEA is associated, independently of weight variation, to change in insulin resistance during a longitudinal weight control dietary program in obese individuals.

PubMed

Montastier, Emilie; Déjean, Sébastien; Le Gall, Caroline; Saris, Wim H M; Langin, Dominique; Viguerie, Nathalie

2014-01-01

Weight loss reduces risk factors associated with obesity. However, long-term metabolic improvement remains a challenge. We investigated quantitative gene expression of subcutaneous adipose tissue in obese individuals and its relationship with low calorie diet and long term weight maintenance induced changes in insulin resistance. Three hundred eleven overweight and obese individuals followed a dietary protocol consisting of an 8-week low calorie diet followed by a 6-month ad libitum weight-maintenance diet. Individuals were clustered according to insulin resistance trajectories assessed using homeostasis model assessment of insulin resistance (HOMA-IR) index. Adipose tissue mRNA levels of 267 genes selected for regulation according to obesity, metabolic status and response to dieting was assessed using high throughput RT-qPCR. A combination of discriminant analyses was used to identify genes with regulation according to insulin resistance trajectories. Partial correlation was used to control for change in body mass index. Three different HOMA-IR profile groups were determined. HOMA-IR improved during low calorie diet in the 3 groups. At the end of the 6-month follow-up, groups A and B had reduced HOMA-IR by 50%. In group C, HOMA-IR had returned to baseline values. Genes were differentially expressed in the adipose tissue of individuals according to groups but a single gene, CIDEA, was common to all phases of the dietary intervention. Changes in adipose tissue CIDEA mRNA levels paralleled variations in insulin sensitivity independently of change in body mass index. Overall, CIDEA was up-regulated in adipose tissue of individuals with successful long term insulin resistance relapse and not in adipose tissue of unsuccessful individuals. The concomitant change in adipose tissue CIDEA mRNA levels and insulin sensitivity suggests a beneficial role of adipose tissue CIDEA in long term glucose homeostasis, independently of weight variation. ClinicalTrials.gov NCT00390637.

Resistin in Dairy Cows: Plasma Concentrations during Early Lactation, Expression and Potential Role in Adipose Tissue

PubMed Central

Reverchon, Maxime; Ramé, Christelle; Cognié, Juliette; Briant, Eric; Elis, Sébastien; Guillaume, Daniel; Dupont, Joëlle

2014-01-01

Resistin is an adipokine that has been implicated in energy metabolism regulation in rodents but has been little studied in dairy cows. We determined plasma resistin concentrations in early lactation in dairy cows and investigated the levels of resistin mRNA and protein in adipose tissue and the phosphorylation of several components of insulin signaling pathways one week post partum (1 WPP) and at five months of gestation (5 MG). We detected resistin in mature bovine adipocytes and investigated the effect of recombinant bovine resistin on lipolysis in bovine adipose tissue explants. ELISA showed that plasma resistin concentration was low before calving, subsequently increasing and reaching a peak at 1 WPP, decreasing steadily thereafter to reach pre-calving levels at 6 WPP. Plasma resistin concentration was significantly positively correlated with plasma non esterified fatty acid (NEFA) levels and negatively with milk yield, dry matter intake and energy balance between WPP1 to WPP22. We showed, by quantitative RT-PCR and western blotting, that resistin mRNA and protein levels in adipose tissue were higher at WPP1 than at 5 MG. The level of phosphorylation of several early and downstream insulin signaling components (IRβ, IRS-1, IRS-2, Akt, MAPK ERK1/2, P70S6K and S6) in adipose tissue was also lower at 1 WPP than at 5 MG. Finally, we showed that recombinant bovine resistin increased the release of glycerol and mRNA levels for ATGL (adipose triglyceride lipase) and HSL (hormone-sensitive lipase) in adipose tissue explants. Overall, resistin levels were high in the plasma and adipose tissue and were positively correlated with NEFA levels after calving. Resistin is expressed in bovine mature adipocytes and promotes lipid mobilization in adipose explants in vitro. PMID:24675707

Liver attenuation, pericardial adipose tissue, obesity, and insulin resistance: the Multi-Ethnic Study of Atherosclerosis (MESA).

PubMed

McAuley, Paul A; Hsu, Fang-Chi; Loman, Kurt K; Carr, J Jeffrey; Budoff, Matthew J; Szklo, Moyses; Sharrett, A Richey; Ding, Jingzhong

2011-09-01

Insulin resistance is linked to general and abdominal obesity, but its relation to hepatic lipid content and pericardial adipose tissue is less clear. The purpose of this study was to examine cross-sectional associations of liver attenuation, pericardial adipose tissue, BMI, and waist circumference with insulin resistance. We measured liver attenuation and pericardial adipose tissue using the existing cardiac computed tomography scans in 5,291 individuals free of clinical cardiovascular disease and diabetes in the Multi-Ethnic Study of Atherosclerosis (MESA) during the study's baseline visit (2000-2002). Low liver attenuation was defined as the lowest quartile and high pericardial adipose tissue as the upper quartile of volume (cm(3)). We used standard clinical definitions for obesity and abdominal obesity. Insulin resistance was assessed by the homeostasis model assessment of insulin resistance (HOMA(IR)) index. In multivariate linear regression with all adiposity measures in the model simultaneously, all adiposity measures were significantly (P < 0.0001) associated with insulin resistance: regression coefficients (±s.e.) were 0.31 (±0.02) for low liver attenuation, 0.27 (±0.02) for high pericardial adipose tissue, 0.27 (±0.02) for obesity, and 0.32 (±0.02) for abdominal obesity. We found significant differences (P = 0.003) between standardized liver attenuation and insulin resistance by ethnicity: regression coefficients per 1 s.d. increment were 0.10 ± 0.01 for whites, 0.11 ± 0.02 for Chinese, 0.08 ± 0.2 for blacks, and 0.14 ± 0.01 for Hispanics. Liver attenuation and pericardial adipose tissue were associated with insulin resistance, independent of BMI and waist circumference.

Adipose tissue transcriptome changes during obesity development in female dogs.

PubMed

Grant, Ryan W; Vester Boler, Brittany M; Ridge, Tonya K; Graves, Thomas K; Swanson, Kelly S

2011-03-29

During the development of obesity, adipose tissue undergoes major expansion and remodeling, but the biological processes involved in this transition are not well understood. The objective of this study was to analyze global gene expression profiles of adipose tissue in dogs, fed a high-fat diet, during the transition from a lean to obese phenotype. Nine female beagles (4.09 ± 0.64 yr; 8.48 ± 0.35 kg) were randomized to ad libitum feeding or body weight maintenance. Subcutaneous adipose tissue biopsy, blood, and dual x-ray absorptiometry measurements were collected at 0, 4, 8, 12, and 24 wk of feeding. Serum was analyzed for glucose, insulin, fructosamine, triglycerides, free fatty acids, adiponectin, and leptin. Formalin-fixed adipose tissue was used for determination of adipocyte size. Adipose RNA samples were hybridized to Affymetrix Canine 2.0 microarrays. Statistical analysis, using repeated-measures ANOVA, showed ad libitum feeding increased (P < 0.05) body weight (0 wk, 8.36 ± 0.34 kg; 24 wk, 14.64 ± 0.34 kg), body fat mass (0 wk, 1.36 ± 0.24 kg; 24 wk, 6.52 ± 0.24 kg), adipocyte size (0 wk, 114.66 ± 17.38 μm(2); 24 wk, 320.97 ± 0.18.17 μm(2)), and leptin (0 wk, 0.8 ± 1.0 ng/ml; 24 wk, 12.9 ± 1.0 ng/ml). Microarrays displayed 1,665 differentially expressed genes in adipose tissue as weight increased. Alterations were seen in adipose tissue homeostatic processes including metabolism, oxidative stress, mitochondrial homeostasis, and extracellular matrix. Adipose transcriptome changes highlight the dynamic and adaptive response to ad libitum feeding and obesity development.

Free Fatty Acid Storage in Human Visceral and Subcutaneous Adipose Tissue

PubMed Central

Ali, Asem H.; Koutsari, Christina; Mundi, Manpreet; Stegall, Mark D.; Heimbach, Julie K.; Taler, Sandra J.; Nygren, Jonas; Thorell, Anders; Bogachus, Lindsey D.; Turcotte, Lorraine P.; Bernlohr, David; Jensen, Michael D.

2011-01-01

OBJECTIVE Because direct adipose tissue free fatty acid (FFA) storage may contribute to body fat distribution, we measured FFA (palmitate) storage rates and fatty acid (FA) storage enzymes/proteins in omental and abdominal subcutaneous fat. RESEARCH DESIGN AND METHODS Elective surgery patients received a bolus of [1-14C]palmitate followed by omental and abdominal subcutaneous fat biopsies to measure direct FFA storage. Long chain acyl-CoA synthetase (ACS) and diacylglycerol acyltransferase activities, CD36, fatty acid-binding protein, and fatty acid transport protein 1 were measured. RESULTS Palmitate tracer storage (dpm/g adipose lipid) and calculated palmitate storage rates were greater in omental than abdominal subcutaneous fat in women (1.2 ± 0.8 vs. 0.7 ± 0.4 μmol ⋅ kg adipose lipid−1 ⋅ min−1, P = 0.005) and men (0.7 ± 0.2 vs. 0.2 ± 0.1, P < 0.001), and both were greater in women than men (P < 0.0001). Abdominal subcutaneous adipose tissue palmitate storage rates correlated with ACS activity (women: r = 0.66, P = 0.001; men: r = 0.70, P = 0.007); in men, CD36 was also independently related to palmitate storage rates. The content/activity of FA storage enzymes/proteins in omental fat was dramatically lower in those with more visceral fat. In women, only omental palmitate storage rates were correlated (r = 0.54, P = 0.03) with ACS activity. CONCLUSIONS Some adipocyte FA storage factors correlate with direct FFA storage, but sex differences in this process in visceral fat do not account for sex differences in visceral fatness. The reduced storage proteins in those with greater visceral fat suggest that the storage factors we measured are not a predominant cause of visceral adipose tissue accumulation. PMID:21810594

Decreased RB1 mRNA, Protein, and Activity Reflect Obesity-Induced Altered Adipogenic Capacity in Human Adipose Tissue

PubMed Central

Moreno-Navarrete, José María; Petrov, Petar; Serrano, Marta; Ortega, Francisco; García-Ruiz, Estefanía; Oliver, Paula; Ribot, Joan; Ricart, Wifredo; Palou, Andreu; Bonet, Mª Luisa; Fernández-Real, José Manuel

2013-01-01

Retinoblastoma (Rb1) has been described as an essential player in white adipocyte differentiation in mice. No studies have been reported thus far in human adipose tissue or human adipocytes. We aimed to investigate the possible role and regulation of RB1 in adipose tissue in obesity using human samples and animal and cell models. Adipose RB1 (mRNA, protein, and activity) was negatively associated with BMI and insulin resistance (HOMA-IR) while positively associated with the expression of adipogenic genes (PPARγ and IRS1) in both visceral and subcutaneous human adipose tissue. BMI increase was the main contributor to adipose RB1 downregulation. In rats, adipose Rb1 gene expression and activity decreased in parallel to dietary-induced weight gain and returned to baseline with weight loss. RB1 gene and protein expression and activity increased significantly during human adipocyte differentiation. In fully differentiated adipocytes, transient knockdown of Rb1 led to loss of the adipogenic phenotype. In conclusion, Rb1 seems to play a permissive role for human adipose tissue function, being downregulated in obesity and increased during differentiation of human adipocytes. Rb1 knockdown findings further implicate Rb1 as necessary for maintenance of adipogenic characteristics in fully differentiated adipocytes. PMID:23315497

UCP1 in adipose tissues: two steps to full browning.

PubMed

Kalinovich, Anastasia V; de Jong, Jasper M A; Cannon, Barbara; Nedergaard, Jan

2017-03-01

The possibility that brown adipose tissue thermogenesis can be recruited in order to combat the development of obesity has led to a high interest in the identification of "browning agents", i.e. agents that increase the amount and activity of UCP1 in brown and brite/beige adipose tissues. However, functional analysis of the browning process yields confusingly different results when the analysis is performed in one of two alternative steps. Thus, in one of the steps, using cold acclimation as a potent model browning agent, we find that if the browning process is followed in mice initially housed at 21 °C (the most common procedure), there is only weak molecular evidence for increases in UCP1 gene expression or UCP1 protein abundance in classical brown adipose tissue; however, in brite/beige adipose depots, there are large increases, apparently associating functional browning with events only in the brite/beige tissues. Contrastingly, in another step, if the process is followed starting with mice initially housed at 30 °C (thermoneutrality for mice, thus similar to normal human conditions), large increases in UCP1 gene expression and UCP1 protein abundance are observed in the classical brown adipose tissue depots; there is then practically no observable UCP1 gene expression in brite/beige tissues. This apparent conundrum can be resolved when it is realized that the classical brown adipose tissue at 21 °C is already essentially fully differentiated and thus expands extensively through proliferation upon further browning induction, rather than by further enhancing cellular differentiation. When the limiting factor for thermogenesis, i.e. the total amount of UCP1 protein per depot, is analyzed, classical brown adipose tissue is by far the predominant site for the browning process, irrespective of which of the two steps is analyzed. There are to date no published data demonstrating that alternative browning agents would selectively promote brite/beige tissues versus classical brown tissue to a higher degree than does cold acclimation. Thus, to restrict investigations to examine adipose tissue depots where only a limited part of the adaptation process occurs (i.e. the brite/beige tissues) and to use initial conditions different from the thermoneutrality normally experienced by adult humans may seriously hamper the identification of therapeutically valid browning agents. The data presented here have therefore important implications for the analysis of the potential of browning agents and the nature of human brown adipose tissue. Copyright © 2017 The Author(s). Published by Elsevier B.V. All rights reserved.

Differences in prostate and adipose tissue basic fibroblast growth factor: analysis of preliminary results.

PubMed

Mydlo, J H; Kral, J G; Macchia, R J

1997-09-01

Basic fibroblast growth factor (bFGF or FGF-2) is mitogenic to human prostate epithelial and stromal cells, and it is reported to be elevated in the serum and urine of patients with various cancers, including prostate cancer. Obesity, with increased body fat, is a risk factor for prostate cancer through unknown mechanisms. Because adipose tissue is a source of FGF-2, we determined the quantity and quality of activity of FGF-2 in omental adipose tissue and compared it with normal and cancerous prostate tissues. Using heparin-Sepharose chromatography, we extracted proteins from human omental adipose tissue, adenocarcinoma of the prostate, and benign prostatic hypertrophic (BPH) tissues. Each of the mitogenic proteins eluted with NaCl concentrations between 1.4 M and 1.8 M, similar to control FGF-2. Using FGF-2 antisera (which inhibited the mitogenic activity of the proteins), we performed Western blot analysis to confirm their homology to FGF-2. We also assessed recovery, mitogenicity, and angiogenicity of each of the proteins using thymidine incorporation into human umbilical vein endothelial cells and the chorioallantoic membrane assay. There was greater recovery of FGF-2 from omental adipose tissue compared with cancerous or BPH homogenates (40 micrograms [2.0 micrograms/g] versus 25 micrograms [1.25 micrograms/g] and 20 micrograms [1.0 microgram/g], respectively). Moreover. FGF-2 from adipose tissue had greater mitogenic activity (96.2% versus 74.8% and 54%; P < 0.05) and a greater angiogenic activity (5.1 vessels versus 2.9 and 1.8 vessels; P < 0.05) on the chorioallantoic assay. We suggest that human omental adipose tissue FGF-2 may demonstrate greater mitogenic and angiogenic activity than either BPH or prostate cancer tissue FGF-2. It is not known whether FGF-2 from adipose tissue qualitatively or quantitatively may underlie the relationship between obesity and prostate cancer.

Post-Mortem Stability of RNA in Skeletal Muscle and Adipose Tissue and the Tissue-Specific Expression of Myostatin, Perilipin and Associated Factors in the Horse

PubMed Central

Morrison, Philippa K.; Bing, Chen; Harris, Patricia A.; Maltin, Charlotte A.; Grove-White, Dai; Argo, Caroline McG.

2014-01-01

Obesity, a major concern for equine welfare, is highly prevalent in the leisure horse population. Skeletal-muscle and adipose tissues are important determinants of maintenance energy requirements. The myostatin and perilipin pathways play key roles in the regulation of muscle mass and lipolysis respectively and have both been associated with obesity predisposition in other mammalian species. High quality samples, suitable for molecular biology, are an essential prerequisite for detailed investigations of gene and protein expression. Hence, this study has evaluated a) the post-mortem stability of RNA extracted from skeletal-muscle and adipose-tissues collected under commercial conditions and b) the tissue-specific presence of myostatin, the moystatin receptor (activin receptor IIB, ActRIIB), follistatin and perilipin, genes and proteins across a range of equine tissues. Objectives were addressed using tissues from 7 Thoroughbred horses presented for slaughter at a commercial abattoir; a) samples were collected at 7 time-points from Masseter muscle and perirenal adipose from 5 minutes to 6 hours post-mortem. Extracted RN was appraised by Optical Density analysis and agarose-gel electrophoresis. b) Quantitative real time PCR and Western Blotting were used to evaluate gene and protein expression in anatomically-defined samples collected from 17 tissues (6 organs, 4 skeletal muscles and 7 discrete adipose depots). The results indicate that, under the present collection conditions, intact, good quality RNA could be extracted from skeletal-muscle for up to 2 hours post-mortem. However, RNA from adipose tissue may be more susceptible to degradation/contamination and samples should be collected no later than 30 minutes post-mortem. The data also show that myostatin and ActRIIB genes and proteins were almost exclusively expressed in skeletal muscle. The follistatin gene showed a more diverse gene expression profile, with expression evident in several organs, adipose tissue depots and skeletal muscles. Perilipin gene and protein were almost exclusively expressed by adipose tissue. PMID:24956155

DOE Office of Scientific and Technical Information (OSTI.GOV)

Linde, B.; Hjemdahl, P.; Freyschuss, U.

Mental stress (a modified Stroop color word conflict test (CWT)) increased adipose tissue blood flow (ATBF; 133Xe clearance) by 70% and reduced adipose tissue vascular resistance (ATR) by 25% in healthy male volunteers. The vasculatures of adipose tissue (abdomen as well as thigh), skeletal muscle of the calf (133Xe clearance), and the entire calf (venous occlusion plethysmography) responded similarly. Arterial epinephrine (Epi) and glycerol levels were approximately doubled by stress. Beta-Blockade by metoprolol (beta 1-selective) or propranolol (nonselective) attenuated CWT-induced tachycardia similarly. Metoprolol attenuated stress-induced vasodilation in the calf and tended to do so in adipose tissue. Propranolol abolished vasodilationmore » in the calf and resulted in vasoconstriction during CWT in adipose tissue. Decreases in ATR, but not in skeletal muscle or calf vascular resistances, were correlated to increases in arterial plasma glycerol (r = -0.42, P less than 0.05), whereas decreases in skeletal muscle and calf vascular resistances, but not in ATR, were correlated to increases in arterial Epi levels (r = -0.69, P less than 0.01; and r = -0.43, P less than 0.05, respectively). The results suggest that mental stress increases nutritive blood flow in adipose tissue and skeletal muscle considerably, both through the elevation of perfusion pressure and via vasodilatation. Withdrawal of vasoconstrictor nerve activity, vascular beta 2-adrenoceptor stimulation by circulating Epi, and metabolic mechanisms (in adipose tissue) may contribute to the vasodilatation.« less

Soya protein attenuates abnormalities of the renin-angiotensin system in adipose tissue from obese rats.

PubMed

Frigolet, María E; Torres, Nimbe; Tovar, Armando R

2012-01-01

Several metabolic disturbances during obesity are associated with adipose tissue-altered functions. Adipocytes contain the renin-angiotensin system (RAS), which regulates signalling pathways that control angiogenesis via Akt in an autocrine fashion. Soya protein (Soy) consumption modifies the gene expression pattern in adipose tissue, resulting in an improved adipocyte function. Therefore, the aim of the present work is to study whether dietary Soy regulates the expression of RAS and angiogenesis-related genes and its association with the phosphorylated state of Akt in the adipose tissue of obese rats. Animals were fed a 30 % Soy or casein (Cas) diet containing 5 or 25 % fat for 160 d. mRNA abundance was studied in the adipose tissue, and Akt phosphorylation and hormone release were measured in the primary adipocyte culture. The present results show that Soy treatment in comparison with Cas consumption induces lower angiotensin release and increased insulin-stimulated Akt activation in adipocytes. Furthermore, Soy consumption varies the expression of RAS and angiogenesis-related genes, which maintain cell size and vascularity in the adipose tissue of rats fed a high-fat diet. Thus, adipocyte hypertrophy and impaired angiogenesis, which are frequently observed in dysfunctional adipose tissue, were avoided by consuming dietary Soy. Taken together, these findings suggest that Soy can be used as a dietary strategy to preserve adipocyte functionality and to prevent obesity abnormalities.

Toll-like receptor 4 (TLR4) deficient mice are protected from adipose tissue inflammation in aging.

PubMed

Ghosh, Amiya K; O'Brien, Martin; Mau, Theresa; Yung, Raymond

2017-09-07

Adipose tissue (AT) inflammation is a central mechanism for metabolic dysfunction in both diet-induced obesity and age-associated obesity. Studies in diet-induced obesity have characterized the role of Fetuin A (Fet A) in Free Fatty Acids (FFA)-mediated TLR4 activation and adipose tissue inflammation. However, the role of Fet A & TLR4 in aging-related adipose tissue inflammation is unknown. In the current study, analysis of epidymymal fat pads of C57/Bl6 male mice, we found that, in contrast to data from diet-induced obesity models, adipose tissue from aged mice have normal Fet A and TLR4 expression. Interestingly, aged TLR4-deficient mice have diminished adipose tissue inflammation compared to normal controls. We further demonstrated that reduced AT inflammation in old TLR4-deficient mice is linked to impaired ER stress, augmented autophagy activity, and diminished senescence phenomenon. Importantly, old TLR4-deficient mice have improved glucose tolerance compared to age-matched wild type mice, suggesting that the observed reduced AT inflammation in aged TLR4-deficient mice has important physiological consequences. Taken together, our present study establishes novel aspect of aging-associated AT inflammation that is distinct from diet-induced AT inflammation. Our results also provide strong evidence that TLR4 plays a significant role in promoting aging adipose tissue inflammation.

Characterization of Visceral and Subcutaneous Adipose Tissue Transcriptome and Biological Pathways in Pregnant and Non-Pregnant Women: Evidence for Pregnancy-Related Regional-Specific Differences in Adipose Tissue

PubMed Central

Mazaki-Tovi, Shali; Vaisbuch, Edi; Tarca, Adi L.; Kusanovic, Juan Pedro; Than, Nandor Gabor; Chaiworapongsa, Tinnakorn; Dong, Zhong; Hassan, Sonia S.; Romero, Roberto

2015-01-01

Objective The purpose of this study was to compare the transcriptome of visceral and subcutaneous adipose tissues between pregnant and non-pregnant women. Study Design The transcriptome of paired visceral and abdominal subcutaneous adipose tissues from pregnant women at term and matched non-pregnant women (n = 11) was profiled with the Affymetrix Human Exon 1.0 ST array. Differential expression of selected genes was validated with the use of quantitative reverse transcription–polymerase chain reaction. Results Six hundred forty-four transcripts from 633 known genes were differentially expressed (false discovery rate (FDR) <0.1; fold-change >1.5), while 42 exons from 36 genes showed differential usage (difference in FIRMA scores >2 and FDR<0.1) between the visceral and subcutaneous fat of pregnant women. Fifty-six known genes were differentially expressed between pregnant and non-pregnant subcutaneous fat and three genes in the visceral fat. Enriched biological processes in the subcutaneous adipose tissue of pregnant women were mostly related to inflammation. Conclusion The transcriptome of visceral and subcutaneous fat depots reveals pregnancy-related gene expression and splicing differences in both visceral and subcutaneous adipose tissue. Furthermore, for the first time, alternative splicing in adipose tissue has been associated with regional differences and human parturition. PMID:26636677

Toll-like receptor 4 (TLR4) deficient mice are protected from adipose tissue inflammation in aging

PubMed Central

Ghosh, Amiya K.; O'Brien, Martin; Mau, Theresa; Yung, Raymond

2017-01-01

Adipose tissue (AT) inflammation is a central mechanism for metabolic dysfunction in both diet-induced obesity and age-associated obesity. Studies in diet-induced obesity have characterized the role of Fetuin A (Fet A) in Free Fatty Acids (FFA)-mediated TLR4 activation and adipose tissue inflammation. However, the role of Fet A & TLR4 in aging-related adipose tissue inflammation is unknown. In the current study, analysis of epidymymal fat pads of C57/Bl6 male mice, we found that, in contrast to data from diet-induced obesity models, adipose tissue from aged mice have normal Fet A and TLR4 expression. Interestingly, aged TLR4-deficient mice have diminished adipose tissue inflammation compared to normal controls. We further demonstrated that reduced AT inflammation in old TLR4-deficient mice is linked to impaired ER stress, augmented autophagy activity, and diminished senescence phenomenon. Importantly, old TLR4-deficient mice have improved glucose tolerance compared to age-matched wild type mice, suggesting that the observed reduced AT inflammation in aged TLR4-deficient mice has important physiological consequences. Taken together, our present study establishes novel aspect of aging-associated AT inflammation that is distinct from diet-induced AT inflammation. Our results also provide strong evidence that TLR4 plays a significant role in promoting aging adipose tissue inflammation. PMID:28898202

Adipose tissue mitochondrial dysfunction triggers a lipodystrophic syndrome with insulin resistance, hepatosteatosis, and cardiovascular complications

PubMed Central

Vernochet, Cecile; Damilano, Federico; Mourier, Arnaud; Bezy, Olivier; Mori, Marcelo A.; Smyth, Graham; Rosenzweig, Anthony; Larsson, Nils-Göran; Kahn, C. Ronald

2014-01-01

Mitochondrial dysfunction in adipose tissue occurs in obesity, type 2 diabetes, and some forms of lipodystrophy, but whether this dysfunction contributes to or is the result of these disorders is unknown. To investigate the physiological consequences of severe mitochondrial impairment in adipose tissue, we generated mice deficient in mitochondrial transcription factor A (TFAM) in adipocytes by using mice carrying adiponectin-Cre and TFAM floxed alleles. These adiponectin TFAM-knockout (adipo-TFAM-KO) mice had a 75–81% reduction in TFAM in the subcutaneous and intra-abdominal white adipose tissue (WAT) and interscapular brown adipose tissue (BAT), causing decreased expression and enzymatic activity of proteins in complexes I, III, and IV of the electron transport chain (ETC). This mitochondrial dysfunction led to adipocyte death and inflammation in WAT and a whitening of BAT. As a result, adipo-TFAM-KO mice were resistant to weight gain, but exhibited insulin resistance on both normal chow and high-fat diets. These lipodystrophic mice also developed hypertension, cardiac hypertrophy, and cardiac dysfunction. Thus, isolated mitochondrial dysfunction in adipose tissue can lead a syndrome of lipodystrophy with metabolic syndrome and cardiovascular complications.—Vernochet, C., Damilano, F., Mourier, A., Bezy, O., Mori, M. A., Smyth, G., Rosenzweig, A., Larsson, N.-G., Kahn, C. R. Adipose tissue mitochondrial dysfunction triggers a lipodystrophic syndrome with insulin resistance, hepatosteatosis, and cardiovascular complications. PMID:25005176

Ghrelin receptor regulates adipose tissue inflammation in aging.

PubMed

Lin, Ligen; Lee, Jong Han; Buras, Eric D; Yu, Kaijiang; Wang, Ruitao; Smith, C Wayne; Wu, Huaizhu; Sheikh-Hamad, David; Sun, Yuxiang

2016-01-01

Aging is commonly associated with low-grade adipose inflammation, which is closely linked to insulin resistance. Ghrelin is the only circulating orexigenic hormone which is known to increase obesity and insulin resistance. We previously reported that the expression of the ghrelin receptor, growth hormone secretagogue receptor (GHS-R), increases in adipose tissues during aging, and old Ghsr(-/-) mice exhibit a lean and insulin-sensitive phenotype. Macrophages are major mediators of adipose tissue inflammation, which consist of pro-inflammatory M1 and anti-inflammatory M2 subtypes. Here, we show that in aged mice, GHS-R ablation promotes macrophage phenotypical shift toward anti-inflammatory M2. Old Ghsrp(-/-) mice have reduced macrophage infiltration, M1/M2 ratio, and pro-inflammatory cytokine expression in white and brown adipose tissues. We also found that peritoneal macrophages of old Ghsrp(-/-) mice produce higher norepinephrine, which is in line with increased alternatively-activated M2 macrophages. Our data further reveal that GHS-R has cell-autonomous effects in macrophages, and GHS-R antagonist suppresses lipopolysaccharide (LPS)-induced inflammatory responses in macrophages. Collectively, our studies demonstrate that ghrelin signaling has an important role in macrophage polarization and adipose tissue inflammation during aging. GHS-R antagonists may serve as a novel and effective therapeutic option for age-associated adipose tissue inflammation and insulin resistance.

Ghrelin receptor regulates adipose tissue inflammation in aging

PubMed Central

Buras, Eric D.; Yu, Kaijiang; Wang, Ruitao; Smith, C. Wayne; Wu, Huaizhu; Sheikh-Hamad, David; Sun, Yuxiang

2016-01-01

Aging is commonly associated with low-grade adipose inflammation, which is closely linked to insulin resistance. Ghrelin is the only circulating orexigenic hormone which is known to increase obesity and insulin resistance. We previously reported that the expression of the ghrelin receptor, growth hormone secretagogue receptor (GHS-R), increases in adipose tissues during aging, and old Ghsr−/− mice exhibit a lean and insulin-sensitive phenotype. Macrophages are major mediators of adipose tissue inflammation, which consist of pro-inflammatory M1 and anti-inflammatory M2 subtypes. Here, we show that in aged mice, GHS-R ablation promotes macrophage phenotypical shift toward anti-inflammatory M2. Old Ghsr−/− mice have reduced macrophage infiltration, M1/M2 ratio, and pro-inflammatory cytokine expression in white and brown adipose tissues. We also found that peritoneal macrophages of old Ghsr−/− mice produce higher norepinephrine, which is in line with increased alternatively-activated M2 macrophages. Our data further reveal that GHS-R has cell-autonomous effects in macrophages, and GHS-R antagonist suppresses lipopolysaccharide (LPS)-induced inflammatory responses in macrophages. Collectively, our studies demonstrate that ghrelin signaling has an important role in macrophage polarization and adipose tissue inflammation during aging. GHS-R antagonists may serve as a novel and effective therapeutic option for age-associated adipose tissue inflammation and insulin resistance. PMID:26837433

The role of adipokines in chronic inflammation

PubMed Central

Mancuso, Peter

2016-01-01

Adipose tissue has traditionally been defined as connective tissue that stores excess calories in the form of triacylglycerol. However, the physiologic functions attributed to adipose tissue are expanding, and it is now well established that adipose tissue is an endocrine gland. Among the endocrine factors elaborated by adipose tissue are the adipokines; hormones, similar in structure to cytokines, produced by adipose tissue in response to changes in adipocyte triacylglycerol storage and local and systemic inflammation. They inform the host regarding long-term energy storage and have a profound influence on reproductive function, blood pressure regulation, energy homeostasis, the immune response, and many other physiologic processes. The adipokines possess pro- and anti-inflammatory properties and play a critical role in integrating systemic metabolism with immune function. In calorie restriction and starvation, proinflammatory adipokines decline and anti-inflammatory adipokines increase, which informs the host of energy deficits and contributes to the suppression of immune function. In individuals with normal metabolic status, there is a balance of pro- and anti-inflammatory adipokines. This balance shifts to favor proinflammatory mediators as adipose tissue expands during the development of obesity. As a consequence, the proinflammatory status of adipose tissue contributes to a chronic low-grade state of inflammation and metabolic disorders associated with obesity. These disturbances are associated with an increased risk of metabolic disease, type 2 diabetes, cardiovascular disease, and many other pathological conditions. This review focuses on the impact of energy homeostasis on the adipokines in immune function. PMID:27529061

Relationship between reflection spectra of breast adipose tissue with histologic grade

NASA Astrophysics Data System (ADS)

Muñoz Morales, Aarón; Vázquez Y Montiel, Sergio; Reigosa, Aldo

2011-08-01

Optical spectroscopy allows the characterization, recognition and differentiation of subcutaneous tissues healthy and no-healthy, to facilitate the diagnosis or early detection for breast cancer are studied white adipose tissue by the subcutaneous region with the help of the diffuse reflection spectroscopy in the visible areas (400 to 700 nm) of electromagnetic spectrum for them using a spectrometer portable of integrating sphere, Hunter lab Model Mini-Scan. The problem to be solved for cancer detection by optical techniques is to find the solution to the inverse problem of scattering of radiation in tissue where it is necessary to solve the equation of energy transfer. us through the trigonometric interpolation and by the data adjustment by least squares using Fourier series expansion to parameterize the spectral response curves of each sample of breast adipose tissue then correlated with histological grades established by the optical biopsy for each one of the samples, allowing use this technique to the study of anomalies in White Adipose Tissue Breast, changes are evident in the spectral response for Breast Adipose Tissue carcinogens with respect to healthy tissues and for the different histological grades.

Stearidonic and eicosapentaenoic acids inhibit interleukin-6 expression in ob/ob mouse adipose stem cells via toll-like receptor-2-mediated pathways

USDA-ARS?s Scientific Manuscript database

Increases in adipose tissue weight positively correlates with increased circulating inflammatory cytokines such as interleukin-6 (IL-6). We previously have shown that adipose stem cell produce significantly higher levels of IL-6 when compared to other cell types in the adipose tissue in genetically ...

Subcutaneous adipose tissue macropage infiltration is associated with hepatic and visceral fat deposition, hyperinsulinemia, and stimulation of NF-kB stress pathway

USDA-ARS?s Scientific Manuscript database

The goal was to examine in obese young adults the influence of ethnicity and subcutaneous adipose tissue (SAT) inflammation on hepatic fat fraction (HFF), visceral adipose tissue (VAT) deposition, insulin sensitivity (SI), Beta-cell function, and SAT gene expression. SAT biopsies were obtained from...

Effects of prenatal low protein and postnatal high fat diets on visceral adipose tissue macrophage phenotypes and IL-6 expression in Sprague Dawley rat offspring

USDA-ARS?s Scientific Manuscript database

Adipose tissue macrophages (ATM) are implicated in adipose tissue inflammation and obesity-related insulin resistance. Maternal low protein models result in fetal programming of obesity. However, it is not known whether maternal undernutrition increases ATM phenotypic expression in F1 offspring. Us...

Global adiposity and thickness of intraperitoneal and mesenteric adipose tissue depots are increased in women with polycystic ovary syndrome (PCOS).

PubMed

Borruel, Susana; Fernández-Durán, Elena; Alpañés, Macarena; Martí, David; Alvarez-Blasco, Francisco; Luque-Ramírez, Manuel; Escobar-Morreale, Héctor F

2013-03-01

Sexual dimorphism suggests a role for androgens in body fat distribution. Women with polycystic ovary syndrome (PCOS), a mainly androgen excess disorder, often present with abdominal obesity and visceral adiposity. We hypothesized that women with PCOS have a masculinized body fat distribution favoring the deposition of fat in visceral and organ-specific adipose tissue depots. This was a case-control study. The study was conducted at an academic hospital. Women with PCOS (n = 55), women without androgen excess (n = 25), and men (n = 26) presenting with similar body mass index participated in the study. There were no interventions. Ultrasound measurements of adipose tissue depots including sc (minimum and maximum), preperitoneal, ip, mesenteric, epicardial, and perirenal fat thickness were obtained and total body fat mass was estimated using a body fat monitor. Men and patients with PCOS had increased amounts of total body fat compared with control women. Men had increased thickness of intraabdominal adipose tissue depots compared with the control women, with the women with PCOS showing intermediate values that were also higher than those of control women in the case of ip and mesenteric fat thickness and was close to reaching statistical significance in the case of epicardial fat thickness. Women with PCOS also showed increased minimum sc fat thickness compared with the control women. Obesity increased the thickness of all of the adipose tissue depots in the 3 groups of subjects. Women with PCOS have higher global adiposity and increased amounts of visceral adipose tissue compared with control women, especially in the ip and mesenteric depots.

Technical note: adipose tissue blood flow in miniature swine (Sus scrofa) using the 133xenon washout technique.

PubMed

Moher, H E; Carey, G B

2002-05-01

The purpose of this study was to examine the 133xenon washout technique as a viable method for measuring adipose tissue blood flow (ATBF) in swine. Using a total of 32 female Yucatan miniature swine (Sus scrofa), the partition coefficient for 133xenon in swine subcutaneous adipose tissue was determined and ATBF was measured at rest and under various physiological conditions. These conditions included feeding, anesthesia, epinephrine infusion, and acute exercise. The effects of epinephrine and acute exercise were examined in both sedentary and exercise-trained swine. The partition coefficient value for 133xenon in swine subcutaneous adipose tissue was 9.23+/-0.26 mL/g (mean +/- SD, n = 10). The average value for resting ATBF in swine was 3.98+/-2.72 mL/(100 g tissue-min) (n = 19). Feeding increased ATBF by approximately fivefold over fasting values, and isoflurane anesthesia significantly decreased ATBF compared to rest (1.64+/-1.12 vs 3.92+/-4.22 mL/[100 g x min], n = 10). A 30-min epinephrine infusion (1 microg/[kg BW x min]) significantly increased ATBF from a resting value of 3.13+/-2.61 to 10.35+/-5.31 mL/(100 g x min) (n = 12). Epinephrine infusion into exercise-trained swine increased ATBF to the same extent as when infused into sedentary swine. An acute, 20-min bout of exercise significantly increased ATBF in swine, and the sedentary swine showed a larger increase in ATBF than their exercise-trained littermates relative to rest: 7.83 vs 2.98 mL/(100 g x min). In conclusion, the 133xenon washout technique appears to be a viable method for measuring ATBF in swine; our findings are comparable to swine ATBF values reported using the microsphere method and are consistent with values reported in animal and human studies.

Adipogenesis of human adipose-derived stem cells within three-dimensional hollow fiber-based bioreactors.

PubMed

Gerlach, Jörg C; Lin, Yen-Chih; Brayfield, Candace A; Minteer, Danielle M; Li, Han; Rubin, J Peter; Marra, Kacey G

2012-01-01

To further differentiate adipose-derived stem cells (ASCs) into mature adipocytes and create three-dimensional (3D) adipose tissue in vitro, we applied multicompartment hollow fiber-based bioreactor technology with decentral mass exchange for more physiological substrate gradients and integral oxygenation. We hypothesize that a dynamic 3D perfusion in such a bioreactor will result in longer-term culture of human adipocytes in vitro, thus providing metabolically active tissue serving as a diagnostic model for screening drugs to treat diabetes. ASCs were isolated from discarded human abdominal subcutaneous adipose tissue and then inoculated into dynamic 3D culture bioreactors to undergo adipogenic differentiation. Insulin-stimulated glucose uptake from the medium was assessed with and without TNF-alpha. 3D adipose tissue was generated in the 3D-bioreactors. Immunohistochemical staining indicated that 3D-bioreactor culture displayed multiple mature adipocyte markers with more unilocular morphologies as compared with two-dimensional (2D) cultures. Results of real-time polymerase chain reaction showed 3D-bioreactor treatment had more efficient differentiation in fatty acid-binding protein 4 expression. Repeated insulin stimulation resulted in increased glucose uptake, with a return to baseline between testing. Importantly, TNF-alpha inhibited glucose uptake, an indication of the metabolic activity of the tissue. 3D bioreactors allow more mature adipocyte differentiation of ASCs compared with traditional 2D culture and generate adipose tissue in vitro for up to 2 months. Reproducible metabolic activity of the adipose tissue in the bioreactor was demonstrated, which is potentially useful for drug discovery. We present here, to the best of our knowledge for the first time, the development of a coherent 3D high density fat-like tissue consisting of unilocular structure from primary adipose stem cells in vitro.

Regulation of leptin synthesis in white adipose tissue of the female fruit bat, Cynopterus sphinx: role of melatonin with or without insulin.

PubMed

Banerjee, A; Udin, S; Krishna, A

2011-02-01

Factors regulating leptin synthesis during adipogenesis in wild species are not well known. Studies in the female Cynopterus sphinx bat have shown that it undergoes seasonal changes in its fat deposition and serum leptin and melatonin levels. The aim of the present study was to investigate the hormonal regulation of leptin synthesis by the white adipose tissue during the period of fat deposition in female C. sphinx. This study showed a significant correlation between the seasonal changes in serum melatonin level with the circulating leptin level (r = 0.78; P < 0.05) and with the changes in body fat mass (r = 0.88; P < 0.05) in C. sphinx. A significant correlation between circulating insulin and leptin levels (r = 0.65; P < 0.05) was also found in this species. This in vivo finding suggests that melatonin together with insulin may enhance leptin synthesis by increasing adipose tissue accumulation. The in vitro study showed that melatonin interacts synergistically with insulin in stimulating leptin synthesis by adipose tissue in C. sphinx. The study showed MT(2) receptors in adipose tissue and a stimulatory effect of melatonin on leptin synthesis, which was blocked by treatment with an MT(2) receptor antagonist, suggesting that the effect of melatonin on leptin synthesis by adipose tissue is mediated through the MT(2) receptor in C. sphinx. The in vitro study showed that the synthesis of leptin is directly proportional to the amount of glucose uptake by the adipose tissue. It further showed that melatonin together with insulin synergistically enhanced the leptin synthesis by adipose tissue through phosphorylation of mitogen-activated protein kinase in C. sphinx.

Peripheral Motor and Sensory Nerve Conduction following Transplantation of Undifferentiated Autologous Adipose Tissue-Derived Stem Cells in a Biodegradable U.S. Food and Drug Administration-Approved Nerve Conduit.

PubMed

Klein, Silvan M; Vykoukal, Jody; Li, De-Pei; Pan, Hui-Lin; Zeitler, Katharina; Alt, Eckhard; Geis, Sebastian; Felthaus, Oliver; Prantl, Lukas

2016-07-01

Conduits preseeded with either Schwann cells or stem cells differentiated into Schwann cells demonstrated promising results for the outcome of nerve regeneration in nerve defects. The concept of this trial combines nerve repair by means of a commercially available nerve guidance conduit and preseeding with autologous, undifferentiated, adipose tissue-derived stem cells. Adipose tissue-derived stem cells were harvested from rats and subsequently seeded onto a U.S. Food and Drug Administration-approved type I collagen conduit. Sciatic nerve gaps 10 mm in length were created, and nerve repair was performed by the transplantation of either conduits preseeded with autologous adipose tissue-derived stem cells or acellular (control group) conduits. After 6 months, the motor and sensory nerve conduction velocity were assessed. Nerves were removed and examined by hematoxylin and eosin, van Gieson, and immunohistochemistry (S100 protein) staining for the quality of axonal regeneration. Nerve gaps treated with adipose tissue-derived stem cells showed superior nerve regeneration, reflected by higher motor and sensory nerve conduction velocity values. The motor and sensory nerve conduction velocity were significantly greater in nerves treated with conduits preseeded with adipose tissue-derived stem cells than in nerves treated with conduits alone (p < 0.05). Increased S100 immunoreactivity was detected for the adipose tissue-derived stem cell group. In this group, axon arrangement inside the conduits was more organized. Transplantation of adipose tissue-derived stem cells significantly improves motor and sensory nerve conduction velocity in peripheral nerve gaps. Preseeded conduits showed a more organized axon arrangement inside the conduit in comparison with nerve conduits alone. The approach used here could readily be translated into a clinical therapy. Therapeutic, V.

Weight loss induced by bariatric surgery restores adipose tissue PNPLA3 expression.

PubMed

Wieser, Verena; Adolph, Timon E; Enrich, Barbara; Moser, Patrizia; Moschen, Alexander R; Tilg, Herbert

2017-02-01

Obesity and its related co-morbidities such as non-alcoholic fatty liver disease (NAFLD) are increasing dramatically worldwide. The genetic variation in Patatin-like phospholipase domain-containing protein 3 (PNPLA3), which is also called adiponutrin (ADPN), in residue 148 (I148M, rs738409) has been associated with NAFLD. However, the regulation and function of PNPLA3 in metabolic diseases remains unclear. Laparoscopic gastric banding (LAGB) of severely obese patients reduces body weight, liver and adipose tissue inflammation. In this study, we investigated whether weight loss induced by LAGB affected PNPLA3 expression in hepatic and adipose tissue. Liver and subcutaneous adipose tissue samples were collected from 28 severely obese patients before and 6 months after LAGB. PNPLA3 expression was assessed by quantitative real-time PCR. To understand whether inflammatory stimuli regulated PNPLA3 expression, we studied the effect of tumour necrosis factor alpha (TNFα) and lipopolysaccharide (LPS) on PNPLA3 expression in human adipocytes and hepatocytes. PNPLA3 was strongly expressed in the liver and clearly detectable in subcutaneous adipose tissue of obese patients. Weight loss induced by LAGB of severely obese patients led to significantly increased adipose, but not hepatic, tissue expression of PNPLA3. Subcutaneous PNPLA3 expression negatively correlated with body-mass-index, fasting glucose and fasting insulin. TNFα potently suppressed PNPLA3 expression in adipocytes but not hepatocytes. Weight loss induced by LAGB restored adipose tissue PNPLA3 expression which is suppressed by TNFα. Further studies will be required to determine the functional impact of PNPLA3 and its related genetic variation on adipose tissue inflammation and NAFLD. © 2016 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Adipogenesis of Human Adipose-Derived Stem Cells Within Three-Dimensional Hollow Fiber-Based Bioreactors

PubMed Central

Gerlach, Jörg C.; Lin, Yen-Chih; Brayfield, Candace A.; Minteer, Danielle M.; Li, Han; Rubin, J. Peter

2012-01-01

To further differentiate adipose-derived stem cells (ASCs) into mature adipocytes and create three-dimensional (3D) adipose tissue in vitro, we applied multicompartment hollow fiber-based bioreactor technology with decentral mass exchange for more physiological substrate gradients and integral oxygenation. We hypothesize that a dynamic 3D perfusion in such a bioreactor will result in longer-term culture of human adipocytes in vitro, thus providing metabolically active tissue serving as a diagnostic model for screening drugs to treat diabetes. ASCs were isolated from discarded human abdominal subcutaneous adipose tissue and then inoculated into dynamic 3D culture bioreactors to undergo adipogenic differentiation. Insulin-stimulated glucose uptake from the medium was assessed with and without TNF-alpha. 3D adipose tissue was generated in the 3D-bioreactors. Immunohistochemical staining indicated that 3D-bioreactor culture displayed multiple mature adipocyte markers with more unilocular morphologies as compared with two-dimensional (2D) cultures. Results of real-time polymerase chain reaction showed 3D-bioreactor treatment had more efficient differentiation in fatty acid-binding protein 4 expression. Repeated insulin stimulation resulted in increased glucose uptake, with a return to baseline between testing. Importantly, TNF-alpha inhibited glucose uptake, an indication of the metabolic activity of the tissue. 3D bioreactors allow more mature adipocyte differentiation of ASCs compared with traditional 2D culture and generate adipose tissue in vitro for up to 2 months. Reproducible metabolic activity of the adipose tissue in the bioreactor was demonstrated, which is potentially useful for drug discovery. We present here, to the best of our knowledge for the first time, the development of a coherent 3D high density fat-like tissue consisting of unilocular structure from primary adipose stem cells in vitro. PMID:21902468

Fatty acids do not pay the toll: effect of SFA and PUFA on human adipose tissue and mature adipocytes inflammation.

PubMed

Murumalla, Ravi Kumar; Gunasekaran, Manoj Kumar; Padhan, Jibesh Kumar; Bencharif, Karima; Gence, Lydie; Festy, Franck; Césari, Maya; Roche, Régis; Hoareau, Laurence

2012-12-21

On the basis that high fat diet induces inflammation in adipose tissue, we wanted to test the effect of dietary saturated and polysunsaturated fatty acids on human adipose tissue and adipocytes inflammation. Moreover we wanted to determine if TLR2 and TLR4 are involved in this pathway. Human adipose tissue and adipocytes primary cultures were treated with endotoxin-free BSA conjugated with SFA (lauric acid and palmitic acid--LA and PA) and PUFA (eicosapentaeneic acid, docosahexaenoic acid and oleic acid--EPA, DHA and OA) with or without LPS. Cytokines were then assayed by ELISA (TNF-alpha, IL-6 and MCP-1). In order to determine if TLR2 and TLR4 are activated by fatty acid (FA), we used HEK-Blue cells transfected by genes from TLR2 or TLR4 pathways associated with secreted alkaline phosphatase reporter gene. None of the FA tested in HEK-Blue cells were able to activate TLR2 or TLR4, which is concordant with the fact that after FA treatment, adipose tissue and adipocytes cytokines levels remain the same as controls. However, all the PUFA tested: DHA, EPA and to a lesser extent OA down-regulated TNF-alpha, IL-6 and MCP-1 secretion in human adipose tissue and adipocytes cultures. This study first confirms that FA do not activate TLR2 and TLR4. Moreover by using endotoxin-free BSA, both SFA and PUFA tested were not proinflammatory in human adipose tissue and adipocytes model. More interestingly we showed that some PUFA exert an anti-inflammatory action in human adipose tissue and adipocytes model. These results are important since they clarify the relationship between dietary fatty acids and inflammation linked to obesity.

Telmisartan Therapy Does Not Improve Lymph Node or Adipose Tissue Fibrosis More Than Continued Antiretroviral Therapy Alone.

PubMed

Utay, Netanya S; Kitch, Douglas W; Yeh, Eunice; Fichtenbaum, Carl J; Lederman, Michael M; Estes, Jacob D; Deleage, Claire; Magyar, Clara; Nelson, Scott D; Klingman, Karen L; Bastow, Barbara; Luque, Amneris E; McComsey, Grace A; Douek, Daniel C; Currier, Judith S; Lake, Jordan E

2018-05-05

Fibrosis in lymph nodes may limit CD4+ T-cell recovery, and lymph node and adipose tissue fibrosis may contribute to inflammation and comorbidities despite antiretroviral therapy (ART). We hypothesized that the angiotensin receptor blocker and peroxisome proliferator-activated receptor γ agonist telmisartan would decrease lymph node or adipose tissue fibrosis in treated human immunodeficiency virus type 1 (HIV) infection. In this 48-week, randomized, controlled trial, adults continued HIV-suppressive ART and received telmisartan or no drug. Collagen I, fibronectin, and phosphorylated SMAD3 (pSMAD3) deposition in lymph nodes, as well as collagen I, collagen VI, and fibronectin deposition in adipose tissue, were quantified by immunohistochemical analysis at weeks 0 and 48. Two-sided rank sum and signed rank tests compared changes over 48 weeks. Forty-four participants enrolled; 35 had paired adipose tissue specimens, and 29 had paired lymph node specimens. The median change overall in the percentage of the area throughout which collagen I was deposited was -2.6 percentage points (P = 0.08) in lymph node specimens and -1.3 percentage points (P = .001) in adipose tissue specimens, with no between-arm differences. In lymph node specimens, pSMAD3 deposition changed by -0.5 percentage points overall (P = .04), with no between-arm differences. Telmisartan attenuated increases in fibronectin deposition (P = .06). In adipose tissue, changes in collagen VI deposition (-1.0 percentage point; P = .001) and fibronectin deposition (-2.4 percentage points; P < .001) were observed, with no between-arm differences. In adults with treated HIV infection, lymph node and adipose tissue fibrosis decreased with continued ART alone, with no additional fibrosis reduction with telmisartan therapy.

Adipose tissue-derived stem cells enhance bioprosthetic mesh repair of ventral hernias.

PubMed

Altman, Andrew M; Abdul Khalek, Feras J; Alt, Eckhard U; Butler, Charles E

2010-09-01

Bioprosthetic mesh used for ventral hernia repair becomes incorporated into the musculofascial edge by cellular infiltration and vascularization. Adipose tissue-derived stem cells promote tissue repair and vascularization and may increase the rate or degree of tissue incorporation. The authors hypothesized that introducing these cells into bioprosthetic mesh would result in adipose tissue-derived stem cell engraftment and proliferation and enhance incorporation of the bioprosthetic mesh. Adipose tissue-derived stem cells were isolated from the subcutaneous adipose tissue of syngeneic Brown Norway rats, expanded in vitro, and labeled with green fluorescent protein. Thirty-six additional rats underwent inlay ventral hernia repair with porcine acellular dermal matrix. Two 12-rat groups had the cells (1.0 x 10(6)) injected directly into the musculofascial/porcine acellular dermal matrix interface after repair or received porcine acellular dermal matrix on which the cells had been preseeded; the 12-rat control group received no stem cells. At 2 weeks, adipose tissue-derived stem cells in both stem cell groups engrafted, survived, migrated, and proliferated. Mean cellular infiltration into porcine acellular dermal matrix at the musculofascial/graft interface was significantly greater in the preseeded and injected stem cell groups than in the control group. Mean vascular infiltration of the porcine acellular dermal matrix was significantly greater in both stem cell groups than in the control group. Preseeded and injected adipose tissue-derived stem cells engraft, migrate, proliferate, and enhance the vascularity of porcine acellular dermal matrix grafts at the musculofascial/graft interface. These cells can thus enhance incorporation of porcine acellular dermal matrix into the abdominal wall after repair of ventral hernias.

Metabolic and Structural Effects of Phosphatidylcholine and Deoxycholate Injections on Subcutaneous Fat

PubMed Central

Reeds, Dominic N.; Mohammed, B. Selma; Klein, Samuel; Boswell, Craig Brian

2013-01-01

Background: Phosphatidylcholine and deoxycholate (PC-DC) injections are a popular nonsurgical method to eliminate unwanted fat. The safety and efficacy of this approach is uncertain. Objective: The authors evaluate the effects of PC-DC treatments on body composition, adipocyte function, and mechanisms responsible for fat loss. Methods: This randomized, open-label study enrolled 13 women with a body mass index (BMI) ≤30 kg/m2 and lower abdominal subcutaneous fat suitable for small-volume liposuction. Patients were randomized by the final digit of their Social Security numbers and received between 2 and 4 PC-DC treatments, spaced 8 weeks apart. One side below the umbilicus was injected with PC-DC. The contralateral, control side received no treatment. Adipose tissue biopsies were performed on the treated side at baseline, 1 week after the first treatment, and 8 weeks after the final treatment. The primary outcome was change in adipose tissue thickness at baseline and 8 weeks after the final treatment. Results: Seven women completed the study. Treatment with PC-DC significantly reduced the thickness of the anterior subcutaneous abdominal fat (P = .004). Adipose tissue showed rapid increases in crown-like structures, macrophage infiltration, and reduced expression of leptin, hormone-sensitive lipase, adipose tissue triglyceride lipase, and CD36. Plasma C-reactive protein, lipid profile, and plasma glucose concentrations were unchanged. Conclusions: PC-DC injections can effectively reduce abdominal fat volume and thickness by inducing adipocyte necrosis. These treatments do not appear to increase circulating markers of inflammation or affect glucose and lipid metabolism. Level of Evidence: 3 PMID:23439063

Adipose Tissue in HIV Infection.

PubMed

Koethe, John R

2017-09-12

HIV infection and antiretroviral therapy (ART) treatment exert diverse effects on adipocytes and stromal-vascular fraction cells, leading to changes in adipose tissue quantity, distribution, and energy storage. A HIV-associated lipodystrophic condition was recognized early in the epidemic, characterized by clinically apparent changes in subcutaneous, visceral, and dorsocervical adipose depots. Underlying these changes is altered adipose tissue morphology and expression of genes central to adipocyte maturation, regulation, metabolism, and cytokine signaling. HIV viral proteins persist in circulation and locally within adipose tissue despite suppression of plasma viremia on ART, and exposure to these proteins impairs preadipocyte maturation and reduces adipocyte expression of peroxisome proliferator-activated receptor gamma (PPAR-γ) and other genes involved in cell regulation. Several early nucleoside reverse transcriptase inhibitor and protease inhibitor antiretroviral drugs demonstrated substantial adipocyte toxicity, including reduced mitochondrial DNA content and respiratory chain enzymes, reduced PPAR-γ and other regulatory gene expression, and increased proinflammatory cytokine production. Newer-generation agents, such as integrase inhibitors, appear to have fewer adverse effects. HIV infection also alters the balance of CD4+ and CD8+ T cells in adipose tissue, with effects on macrophage activation and local inflammation, while the presence of latently infected CD4+ T cells in adipose tissue may constitute a protected viral reservoir. This review provides a synthesis of the literature on how HIV virus, ART treatment, and host characteristics interact to affect adipose tissue distribution, immunology, and contribution to metabolic health, and adipocyte maturation, cellular regulation, and energy storage. © 2017 American Physiological Society. Compr Physiol 7:1339-1357, 2017. Copyright © 2017 John Wiley & Sons, Inc.

Adipose tissue lipolysis and energy metabolism in early cancer cachexia in mice

PubMed Central

Kliewer, Kara L; Ke, Jia-Yu; Tian, Min; Cole, Rachel M; Andridge, Rebecca R; Belury, Martha A

2015-01-01

Cancer cachexia is a progressive metabolic disorder that results in depletion of adipose tissue and skeletal muscle. A growing body of literature suggests that maintaining adipose tissue mass in cachexia may improve quality-of-life and survival outcomes. Studies of lipid metabolism in cachexia, however, have generally focused on later stages of the disorder when severe loss of adipose tissue has already occurred. Here, we investigated lipid metabolism in adipose, liver and muscle tissues during early stage cachexia – before severe fat loss – in the colon-26 murine model of cachexia. White adipose tissue mass in cachectic mice was moderately reduced (34–42%) and weight loss was less than 10% of initial body weight in this study of early cachexia. In white adipose depots of cachectic mice, we found evidence of enhanced protein kinase A - activated lipolysis which coincided with elevated total energy expenditure and increased expression of markers of brown (but not white) adipose tissue thermogenesis and the acute phase response. Total lipids in liver and muscle were unchanged in early cachexia while markers of fatty oxidation were increased. Many of these initial metabolic responses contrast with reports of lipid metabolism in later stages of cachexia. Our observations suggest intervention studies to preserve fat mass in cachexia should be tailored to the stage of cachexia. Our observations also highlight a need for studies that delineate the contribution of cachexia stage and animal model to altered lipid metabolism in cancer cachexia and identify those that most closely mimic the human condition. PMID:25457061

Characteristics of adipose tissue macrophages and macrophage-derived insulin-like growth factor-1 in virus-induced obesity.

PubMed

Park, S; Park, H-L; Lee, S-Y; Nam, J-H

2016-03-01

Various pathogens are implicated in the induction of obesity. Previous studies have confirmed that human adenovirus 36 (Ad36) is associated with increased adiposity, improved glycemic control and induction of inflammation. The Ad36-induced inflammation is reflected in the infiltration of macrophages into adipose tissue. However, the characteristics and role of adipose tissue macrophages (ATMs) and macrophage-secreted factors in virus-induced obesity (VIO) are unclear. Although insulin-like growth factor-1 (IGF-1) is involved in obesity metabolism, the contribution of IGF secreted by macrophages in VIO has not been studied. Four-week-old male mice were studied 1 week and 12 weeks after Ad36 infection for determining the characteristics of ATMs in VIO and diet-induced obesity (DIO). In addition, macrophage-specific IGF-1-deficient (MIKO) mice were used to study the involvement of IGF-1 in VIO. In the early stage of VIO (1 week after Ad36 infection), the M1 ATM sub-population increased, which increased the M1/M2 ratio, whereas DIO did not cause this change. In the late stage of VIO (12 weeks after Ad36 infection), the M1/M2 ratio did not change because the M1 and M2 ATM sub-populations increased to a similar extent, despite an increase in adiposity. By contrast, DIO increased the M1/M2 ratio. In addition, VIO in wild-type mice upregulated angiogenesis in adipose tissue and improved glycemic control. However, MIKO mice showed no increase in adiposity, angiogenesis, infiltration of macrophages into adipose tissue, or improvement in glycemic control after Ad36 infection. These data suggest that IGF-1 secreted by macrophages may contribute to hyperplasia and hypertrophy in adipose tissue by increasing angiogenesis, which helps to maintain the 'adipose tissue robustness'.

Quantitative relationship between the octanol/water partition coefficient and the diffusion limitation of the exchange between adipose and blood

PubMed Central

2010-01-01

Background The goal of physiologically based pharmacokinetics (PBPK) is to predict drug kinetics from an understanding of the organ/blood exchange. The standard approach is to assume that the organ is "flow limited" which means that the venous blood leaving the organ equilibrates with the well-stirred tissue compartment. Although this assumption is valid for most solutes, it has been shown to be incorrect for several very highly fat soluble compounds which appear to be "diffusion limited". This paper describes the physical basis of this adipose diffusion limitation and its quantitative dependence on the blood/water (Kbld-wat) and octanol/water (Kow) partition coefficient. Methods Experimental measurements of the time dependent rat blood and adipose concentration following either intravenous or oral input were used to estimate the "apparent" adipose perfusion rate (FA) assuming that the tissue is flow limited. It is shown that the ratio of FA to the anatomic perfusion rate (F) provides a measure of the diffusion limitation. A quantitative relationship between this diffusion limitation and Kbld-wat and Kow is derived. This analysis was applied to previously published data, including the Oberg et. al. measurements of the rat plasma and adipose tissue concentration following an oral dose of a mixture of 13 different polychlorinated biphenyls. Results Solutes become diffusion limited at values of log Kow greater than about 5.6, with the adipose-blood exchange rate reduced by a factor of about 30 for a solute with a log Kow of 7.36. Quantitatively, a plot of FA/F versus Kow is well described assuming an adipose permeability-surface area product (PS) of 750/min. This PS corresponds to a 0.14 micron aqueous layer separating the well-stirred blood from the adipose lipid. This is approximately equal to the thickness of the rat adipose capillary endothelium. Conclusions These results can be used to quantitate the adipose-blood diffusion limitation as a function of Kow. This is especially important for the highly fat soluble persistent organic chemicals (e.g. polychlorinated biphenyls, dioxins) whose pharmacokinetics are primarily determined by the adipose-blood exchange kinetics. PMID:20055995

Pharmacokinetic Models for the Elimination of Drinking Water Contaminants from the Body,

DTIC Science & Technology

1990-03-01

that are sequestered in the bones (lead, barium), in certain soft tissues such as the kidney ( cadmium ), and in the adipose tissue (DDT...slow" component (sequestered in 3 bone or in adipose tissue ). Finally, much more attention must be given to differences among I individuals and among...lead from bone, effectively reducing the half-life. Fasting or starvation can mobilize toxicants 3 stored in adipose tissue . Competition for enzyme

[Isolation,culture and identification of adipose-derived stem cells from SD rat adipose tissues subjected to long-term cryopreservation].

PubMed

Liu, Qin; Wang, Liping; Chen, Fang; Zhang, Yi

2017-02-01

To study the feasibility of isolation and culture of adipose-derived stem cells( ADSCs) from SD rat adipose tissues subjected to long-term cryopreservation. We took inguinal fat pads from healthy SD rats. Adipose tissues were stored with 100 m L / L dimethyl sulfoxide( DMSO) combined with 900 m L / L fetal bovine serum( FBS) in liquid nitrogen. Three months later,the adipose tissues were resuscitated for the isolation and culture of ADSCs. The growth status and morphology were observed. The growth curve and cell surface markers CD29,CD45,CD90 of the 3rd passage cells were analyzed respectively by CCK-8 assay and immunocytochemistry. The 3rd passage cells were induced towards adipogenic lineages and osteogenic lineages by different inducers,and the resulting cells were examined separately by oil red O staining and alizarin red staining. The ADSCs obtained from SD rat adipose tissues subjected to long-term cryopreservation showed a spindle-shape appearance and had a good proliferation ability. The cell growth curve was typical "S " curve.Immunocytochemistry showed that the 3rd passage cells were positive for CD29 and CD90,while negative for CD45. The cells were positive for oil red O staining after adipogenic induction,and also positive for alizarin red staining after osteogenic induction. The ADSCs can be isolated from SD rat adipose tissues subjected to long-term cryopreservation.

Inhibition of adipose tissue PPARγ prevents increased adipocyte expansion after lipectomy and exacerbates a glucose-intolerant phenotype.

PubMed

Booth, A D; Magnuson, A M; Cox-York, K A; Wei, Y; Wang, D; Pagliassotti, M J; Foster, M T

2017-04-01

Adipose tissue plays a fundamental role in glucose homeostasis. For example, fat removal (lipectomy, LipX) in lean mice, resulting in a compensatory 50% increase in total fat mass, is associated with significant improvement in glucose tolerance. This study was designed to further examine the link between fat removal, adipose tissue compensation and glucose homeostasis using a peroxisome proliferator-activated receptor γ (PPAR γ; activator of adipogenesis) knockout mouse. The study involved PPARγ knockout (FKOγ) or control mice (CON), subdivided into groups that received LipX or Sham surgery. We reasoned that as the ability of adipose tissue to expand in response to LipX would be compromised in FKOγ mice, so would improvements in glucose homeostasis. In CON mice, LipX increased total adipose depot mass (~60%), adipocyte number (~45%) and changed adipocyte distribution to smaller cells. Glucose tolerance was improved (~30%) in LipX CON mice compared to Shams. In FKOγ mice, LipX did not result in any significant changes in adipose depot mass, adipocyte number or distribution. LipX FKOγ mice were also characterized by reduction of glucose tolerance (~30%) compared to shams. Inhibition of adipose tissue PPARγ prevented LipX-induced increases in adipocyte expansion and produced a glucose-intolerant phenotype. These data support the notion that adipose tissue expansion is critical to maintain and/or improvement in glucose homeostasis. © 2016 John Wiley & Sons Ltd.

Reduced Socs3 expression in adipose tissue protects female mice against obesity-induced insulin resistance.

PubMed

Palanivel, R; Fullerton, M D; Galic, S; Honeyman, J; Hewitt, K A; Jorgensen, S B; Steinberg, G R

2012-11-01

Inflammation in obesity increases the levels of the suppressor of cytokine signalling-3 (SOCS3) protein in adipose tissue, but the physiological importance of this protein in regulating whole-body insulin sensitivity in obesity is not known. We generated Socs3 floxed (wild-type, WT) and Socs3 aP2 (also known as Fabp4)-Cre null (Socs3 AKO) mice. Mice were maintained on either a regular chow or a high-fat diet (HFD) for 16 weeks during which time body mass, adiposity, glucose homeostasis and insulin sensitivity were assessed. The HFD increased SOCS3 levels in adipose tissue of WT but not Socs3 AKO mice. WT and Socs3 AKO mice had similar body mass and adiposity, assessed using computed tomography (CT) imaging, irrespective of diet or sex. On a control chow diet there were no differences in insulin sensitivity or glucose tolerance. When fed a HFD, female but not male Socs3 AKO mice had improved glucose tolerance as well as lower fasting glucose and insulin levels compared with WT littermates. Hyperinsulinaemic-euglycaemic clamps and positron emission tomography (PET) imaging demonstrated that improved insulin sensitivity was due to elevated adipose tissue glucose uptake. Increased insulin-stimulated glucose uptake in adipose tissue was associated with enhanced levels and activating phosphorylation of insulin receptor substrate-1 (IRS1). These data demonstrate that inhibiting SOCS3 production in adipose tissue of female mice is effective for improving whole-body insulin sensitivity in obesity.

Complement Factor H Is Expressed in Adipose Tissue in Association With Insulin Resistance

PubMed Central

Moreno-Navarrete, José María; Martínez-Barricarte, Rubén; Catalán, Victoria; Sabater, Mònica; Gómez-Ambrosi, Javier; Ortega, Francisco José; Ricart, Wifredo; Blüher, Mathias; Frühbeck, Gema; Rodríguez de Cordoba, Santiago; Fernández-Real, José Manuel

2010-01-01

OBJECTIVE Activation of the alternative pathway of the complement system, in which factor H (fH; complement fH [CFH]) is a key regulatory component, has been suggested as a link between obesity and metabolic disorders. Our objective was to study the associations between circulating and adipose tissue gene expressions of CFH and complement factor B (fB; CFB) with obesity and insulin resistance. RESEARCH DESIGN AND METHODS Circulating fH and fB were determined by enzyme-linked immunosorbent assay in 398 subjects. CFH and CFB gene expressions were evaluated in 76 adipose tissue samples, in isolated adipocytes, and in stromovascular cells (SVC) (n = 13). The effects of weight loss and rosiglitazone were investigated in independent cohorts. RESULTS Both circulating fH and fB were associated positively with BMI, waist circumference, triglycerides, and inflammatory parameters and negatively with insulin sensitivity and HDL cholesterol. For the first time, CFH gene expression was detected in human adipose tissue (significantly increased in subcutaneous compared with omental fat). CFH gene expression in omental fat was significantly associated with insulin resistance. In contrast, CFB gene expression was significantly increased in omental fat but also in association with fasting glucose and triglycerides. The SVC fraction was responsible for these differences, although isolated adipocytes also expressed fB and fH at low levels. Both weight loss and rosiglitazone led to significantly decreased circulating fB and fH levels. CONCLUSIONS Increased circulating fH and fB concentrations in subjects with altered glucose tolerance could reflect increased SVC-induced activation of the alternative pathway of complement in omental adipose tissue linked to insulin resistance and metabolic disturbances. PMID:19833879

Lipocalin-2 Deficiency Attenuates Insulin Resistance Associated With Aging and Obesity

PubMed Central

Law, Ivy K.M.; Xu, Aimin; Lam, Karen S.L.; Berger, Thorsten; Mak, Tak W.; Vanhoutte, Paul M.; Liu, Jacky T.C.; Sweeney, Gary; Zhou, Mingyan; Yang, Bo; Wang, Yu

2010-01-01

OBJECTIVE The proinflammatory cytokines/adipokines produced from adipose tissue act in an autocrine and/or endocrine manner to perpetuate local inflammation and to induce peripheral insulin resistance. The present study investigates whether lipocalin-2 deficiency or replenishment with this adipokine has any impact on systemic insulin sensitivity and the underlying mechanisms. METHODS AND RESULTS Under conditions of aging or dietary-/genetic-induced obesity, lipocalin-2 knockout (Lcn2-KO) mice show significantly decreased fasting glucose and insulin levels and improved insulin sensitivity compared with their wild-type littermates. Despite enlarged fat mass, inflammation and the accumulation of lipid peroxidation products are significantly attenuated in the adipose tissues of Lcn2-KO mice. Adipose fatty acid composition of these mice varies significantly from that in wild-type animals. The amounts of arachidonic acid (C20:4 n6) are elevated by aging and obesity and are paradoxically further increased in adipose tissue, but not skeletal muscle and liver of Lcn2-KO mice. On the other hand, the expression and activity of 12-lipoxygenase, an enzyme responsible for metabolizing arachidonic acid, and the production of tumor necrosis factor-α (TNF-α), a critical insulin resistance–inducing factor, are largely inhibited by lipocalin-2 deficiency. Lipocalin-2 stimulates the expression and activity of 12-lipoxygenase and TNF-α production in fat tissues. Cinnamyl-3,4-dihydroxy-α-cyanocinnamate (CDC), an arachidonate lipoxygenase inhibitor, prevents TNF-α expression induced by lipocalin-2. Moreover, treatment with TNF-α neutralization antibody or CDC significantly attenuated the differences of insulin sensitivity between wild-type and Lcn2-KO mice. CONCLUSIONS Lipocalin-2 deficiency protects mice from developing aging- and obesity-induced insulin resistance largely by modulating 12-lipoxygenase and TNF-α levels in adipose tissue. PMID:20068130

γδ T cells producing interleukin-17A regulate adipose regulatory T cell homeostasis and thermogenesis.

PubMed

Kohlgruber, Ayano C; Gal-Oz, Shani T; LaMarche, Nelson M; Shimazaki, Moto; Duquette, Danielle; Nguyen, Hung N; Mina, Amir I; Paras, Tyler; Tavakkoli, Ali; von Andrian, Ulrich; Banks, Alexander S; Shay, Tal; Brenner, Michael B; Lynch, Lydia

2018-05-01

γδ T cells are situated at barrier sites and guard the body from infection and damage. However, little is known about their roles outside of host defense in nonbarrier tissues. Here, we characterize a highly enriched tissue-resident population of γδ T cells in adipose tissue that regulate age-dependent regulatory T cell (T reg ) expansion and control core body temperature in response to environmental fluctuations. Mechanistically, innate PLZF + γδ T cells produced tumor necrosis factor and interleukin (IL) 17 A and determined PDGFRα + and Pdpn + stromal-cell production of IL-33 in adipose tissue. Mice lacking γδ T cells or IL-17A exhibited decreases in both ST2 + T reg cells and IL-33 abundance in visceral adipose tissue. Remarkably, these mice also lacked the ability to regulate core body temperature at thermoneutrality and after cold challenge. Together, these findings uncover important physiological roles for resident γδ T cells in adipose tissue immune homeostasis and body-temperature control.

Identification of differentially expressed genes induced by energy restriction using annealing control primer system from the liver and adipose tissues of broilers.

PubMed

Wang, J W; Chen, W; Kang, X T; Huang, Y Q; Tian, Y D; Wang, Y B

2012-04-01

Female Arbor Acre broilers were divided into 2 groups at 18 d of age. One group of chickens had free access to feed (AL), and the other group of chickens had 30% energy restriction (ER). Adipose and hepatic RNA samples were collected at 48 d of age. We employed an accurate reverse-transcription (RT) PCR method that involves annealing control primers to identify the differentially expressed genes (DEG) between ER and AL groups. Using 20 annealing control primers, 43 differentially expressed bands (40 downregulated and 3 upregulated in the ER group) were detected from the hepatic tissue, whereas no differentially expressed bands were detected from the adipose tissue. It seems that energy restriction could induce more DEG in hepatic tissue than that in adipose tissue and could result in more gene-expression downregulation in hepatic tissue. Eight DEG (6 known and 2 unknown genes) were gained from hepatic tissue and confirmed by RT-PCR, which were all supported by released expressed sequence tag sequences. Their expressions were all downregulated by energy restriction in hepatic tissues. Six known genes are RPL7, RPLP1, FBXL12, ND1, ANTXR2, and SLC22A18, respectively, which seem to play essential roles in the protein translation, energy metabolism, and tumor inhibition. The alterations of gene expression in 3 selected genes, including ND1 (P < 0.01), FBXL12 (P < 0.01), and RPLP1 (P < 0.05), were supported by real-time quantitative RT-PCR reaction. Our data provide new insights on the metabolic state of broilers changed by energy restriction.

Borate-aided anion exchange high-performance liquid chromatography of uridine diphosphate-sugars in brain, heart, adipose and liver tissues.

PubMed

Oikari, Sanna; Venäläinen, Tuula; Tammi, Markku

2014-01-03

In this paper we describe a method optimized for the purification of uridine diphosphate (UDP)-sugars from liver, adipose tissue, brain, and heart, with highly reproducible up to 85% recoveries. Rapid tissue homogenization in cold ethanol, lipid removal by butanol extraction, and purification with a graphitized carbon column resulted in isolation of picomolar quantities of the UDP-sugars from 10 to 30mg of tissue. The UDP-sugars were baseline separated from each other, and from all major nucleotides using a CarboPac PA1 anion exchange column eluted with a gradient of acetate and borate buffers. The extraction and purification protocol produced samples with few unidentified peaks. UDP-N-acetylglucosamine was a dominant UDP-sugar in all the rat tissues studied. However, brain and adipose tissue showed high UDP-glucose levels, equal to that of UDP-N-acetylglucosamine. The UDP-N-acetylglucosamine showed 2.3-2.7 times higher levels than UDP-N-acetylgalactosamine in all tissues, and about the same ratio was found between UDP-glucose and UDP-galactose in adipose tissue and brain (2.6 and 2.8, respectively). Interestingly, the UDP-glucose/UDP-galactose ratio was markedly lower in liver (1.1) and heart (1.7). The UDP-N-acetylglucosamine/UDP-glucuronic acid ratio was also constant, between 9.7 and 7.7, except in liver with the ratio as low as 1.8. The distinct UDP-glucose/galactose ratio, and the abundance of UDP-glucuronic acid may reflect the specific role of liver in glycogen synthesis, and metabolism of hormones and xenobiotics, respectively, using these UDP-sugars as substrates. Copyright © 2013 Elsevier B.V. All rights reserved.

Role of pentoxifylline in non-alcoholic fatty liver disease in high-fat diet-induced obesity in mice

PubMed Central

Acedo, Simone Coghetto; Caria, Cintia Rabelo e Paiva; Gotardo, Érica Martins Ferreira; Pereira, José Aires; Pedrazzoli, José; Ribeiro, Marcelo Lima; Gambero, Alessandra

2015-01-01

AIM: To study pentoxifylline effects in liver and adipose tissue inflammation in obese mice induced by high-fat diet (HFD). METHODS: Male swiss mice (6-wk old) were fed a high-fat diet (HFD; 60% kcal from fat) or AIN-93 (control diet; 15% kcal from fat) for 12 wk and received pentoxifylline intraperitoneally (100 mg/kg per day) for the last 14 d. Glucose homeostasis was evaluated by measurements of basal glucose blood levels and insulin tolerance test two days before the end of the protocol. Final body weight was assessed. Epididymal adipose tissue was collected and weighted for adiposity evaluation. Liver and adipose tissue biopsies were homogenized in solubilization buffer and cytokines were measured in supernatant by enzyme immunoassay or multiplex kit, respectively. Hepatic histopathologic analyses were performed in sections of paraformaldehyde-fixed, paraffin-embedded liver specimens stained with hematoxylin-eosin by an independent pathologist. Steatosis (macrovesicular and microvesicular), ballooning degeneration and inflammation were histopathologically determined. Triglycerides measurements were performed after lipid extraction in liver tissue. RESULTS: Pentoxifylline treatment reduced microsteatosis and tumor necrosis factor (TNF)-α in liver (156.3 ± 17.2 and 62.6 ± 7.6 pg/mL of TNF-α for non-treated and treated obese mice, respectively; P < 0.05). Serum aspartate aminotransferase levels were also reduced (23.2 ± 6.9 and 12.1 ± 1.6 U/L for non-treated and treated obese mice, respectively; P < 0.05) but had no effect on glucose homeostasis. In obese adipose tissue, pentoxifylline reduced TNF-α (106.1 ± 17.6 and 51.1 ± 9.6 pg/mL for non-treated and treated obese mice, respectively; P < 0.05) and interleukin-6 (340.8 ± 51.3 and 166.6 ± 22.5 pg/mL for non-treated and treated obese mice, respectively; P < 0.05) levels; however, leptin (8.1 ± 0.7 and 23.1 ± 2.9 ng/mL for non-treated and treated lean mice, respectively; P < 0.05) and plasminogen activator inhibitor-1 (600.2 ± 32.3 and 1508.6 ± 210.4 pg/mL for non-treated and treated lean mice, respectively; P < 0.05) levels increased in lean adipose tissue. TNF-α level in the liver of lean mice also increased (29.6 ± 6.6 and 75.4 ± 12.6 pg/mL for non-treated and treated lean mice, respectively; P < 0.05) while triglycerides presented a tendency to reduction. CONCLUSION: Pentoxifylline was beneficial in obese mice improving liver and adipose tissue inflammation. Unexpectedly, pentoxifylline increased pro-inflammatory markers in the liver and adipose tissue of lean mice. PMID:26523207

Spatial Statistics for Segmenting Histological Structures in H&E Stained Tissue Images.

PubMed

Nguyen, Luong; Tosun, Akif Burak; Fine, Jeffrey L; Lee, Adrian V; Taylor, D Lansing; Chennubhotla, S Chakra

2017-07-01

Segmenting a broad class of histological structures in transmitted light and/or fluorescence-based images is a prerequisite for determining the pathological basis of cancer, elucidating spatial interactions between histological structures in tumor microenvironments (e.g., tumor infiltrating lymphocytes), facilitating precision medicine studies with deep molecular profiling, and providing an exploratory tool for pathologists. This paper focuses on segmenting histological structures in hematoxylin- and eosin-stained images of breast tissues, e.g., invasive carcinoma, carcinoma in situ, atypical and normal ducts, adipose tissue, and lymphocytes. We propose two graph-theoretic segmentation methods based on local spatial color and nuclei neighborhood statistics. For benchmarking, we curated a data set of 232 high-power field breast tissue images together with expertly annotated ground truth. To accurately model the preference for histological structures (ducts, vessels, tumor nets, adipose, etc.) over the remaining connective tissue and non-tissue areas in ground truth annotations, we propose a new region-based score for evaluating segmentation algorithms. We demonstrate the improvement of our proposed methods over the state-of-the-art algorithms in both region- and boundary-based performance measures.

Increased lipolysis, diminished adipose tissue insulin sensitivity and impaired B-cell function relative to adipose tissue insulin sensitivity in obese youth with impaired glucose tolerance (IGT)

USDA-ARS?s Scientific Manuscript database

Despite evidence of insulin resistance and B-cell dysfunction in glucose metabolism in youth with prediabetes, the relationship between adipose tissue insulin sensitivity (ATIS) and B-cell function remains unknown. We investigated whole-body lipolysis, ATIS and B-cell function relative to ATIS [adip...

Expression of interleukins, neuropeptides, and growth hormone receptor and leptin receptor genes in adipose tissue from growing broiler chickens

USDA-ARS?s Scientific Manuscript database

In this study, total RNA was collected from abdominal adipose tissue samples obtained from ten broiler chickens at 3, 4, 5, and 6 weeks of age and prepared for quantitative real-time PCR analysis. Studies of the gene expression of cytokines and associated genes in chicken adipose tissue were initia...

Adipose tissue as an endocrine organ.

PubMed

McGown, Christine; Birerdinc, Aybike; Younossi, Zobair M

2014-02-01

Obesity is one of the most important health challenges faced by developed countries and is increasingly affecting adolescents and children. Obesity is also a considerable risk factor for the development of numerous other chronic diseases, such as insulin resistance, type 2 diabetes, heart disease and nonalcoholic fatty liver disease. The epidemic proportions of obesity and its numerous comorbidities are bringing into focus the highly complex and metabolically active adipose tissue. Adipose tissue is increasingly being considered as a functional endocrine organ. This article discusses the endocrine effects of adipose tissue during obesity and the systemic impact of this signaling. Copyright © 2014 Elsevier Inc. All rights reserved.

Prognostic Effect of Low Subcutaneous Adipose Tissue on Survival Outcome in Patients With Multiple Myeloma.

PubMed

Takeoka, Yasunobu; Sakatoku, Kazuki; Miura, Akiko; Yamamura, Ryosuke; Araki, Taku; Seura, Hirotaka; Okamura, Terue; Koh, Hideo; Nakamae, Hirohisa; Hino, Masayuki; Ohta, Kensuke

2016-08-01

Increasing evidence suggests that decreased skeletal muscle mass (sarcopenia) or adipose tissue assessed using computed tomography (CT) predicts negative outcomes in patients with solid tumors. However, the prognostic value of such an assessment in multiple myeloma (MM) remains unknown. Consecutive patients with newly diagnosed symptomatic MM were retrospectively analyzed. The cross-sectional area of skeletal muscles and subcutaneous or visceral adipose tissue was measured using CT. Body composition indexes (skeletal muscle index, subcutaneous adipose tissue index [SAI], and visceral adipose tissue index) were calculated. The association between these indexes and overall survival (OS) was examined. Of 56 evaluable patients, 37 (66%) had sarcopenia. The 2-year OS in patients with SAI < median was 58% compared with 91% in those with SAI ≥ median (P = .006). In multivariate analyses, SAI < median was significantly associated with poor OS (hazard ratio, 4.05; P = .02). Sarcopenia was not associated with OS. The maximum value of the standardized uptake value was significantly higher in patients with SAI < median (P = .02). The findings of this study suggest that low subcutaneous adipose tissue at baseline predicts poor survival outcome in patients with MM. Copyright © 2016 Elsevier Inc. All rights reserved.

Inorganic Nitrate Promotes the Browning of White Adipose Tissue through the Nitrate-Nitrite-Nitric Oxide Pathway

PubMed Central

Roberts, Lee D; Ashmore, Tom; Kotwica, Aleksandra O; Murfitt, Steven A; Fernandez, Bernadette O; Feelisch, Martin; Griffin, Julian L

2015-01-01

Inorganic nitrate was once considered an oxidation end-product of nitric oxide metabolism with little biological activity. However, recent studies have demonstrated that dietary nitrate can modulate mitochondrial function in man and is effective in reversing features of the metabolic syndrome in mice. Using a combined histological, metabolomics, and transcriptional and protein analysis approach we mechanistically define that nitrate not only increases the expression of thermogenic genes in brown-adipose tissue but also induces the expression of brown adipocyte-specific genes and proteins in white adipose tissue, substantially increasing oxygen consumption and fatty acid β-oxidation in adipocytes. Nitrate induces these phenotypic changes through a mechanism distinct from known physiological small molecule activators of browning, the recently identified nitrate-nitrite-nitric oxide pathway. The nitrate-induced browning effect was enhanced in hypoxia, a serious co-morbidity affecting white adipose tissue in obese individuals, and corrected impaired brown adipocyte-specific gene expression in white adipose tissue in a murine model of obesity. Since resulting beige/brite cells exhibit anti-obesity and anti-diabetic effects, nitrate may be an effective means of inducing the browning response in adipose tissue to treat the metabolic syndrome. PMID:25249574

(n-3) Fatty Acids Alleviate Adipose Tissue Inflammation and Insulin Resistance: Mechanistic Insights12

PubMed Central

Kalupahana, Nishan S.; Claycombe, Kate J.; Moustaid-Moussa, Naima

2011-01-01

Obesity is associated with the metabolic syndrome, a significant risk factor for developing type 2 diabetes and cardiovascular diseases. Chronic low-grade inflammation occurring in the adipose tissue of obese individuals is causally linked to the pathogenesis of insulin resistance and the metabolic syndrome. Although the exact trigger of this inflammatory process is unknown, adipose tissue hypoxia, endoplasmic reticular stress, and saturated fatty acid–mediated activation of innate immune processes have been identified as important processes in these disorders. Furthermore, macrophages and T lymphocytes have important roles in orchestrating this immune process. Although energy restriction leading to weight loss is the primary dietary intervention to reverse these obesity-associated metabolic disorders, other interventions targeted at alleviating adipose tissue inflammation have not been explored in detail. In this regard, (n-3) PUFA of marine origin both prevent and reverse high-fat-diet–induced adipose tissue inflammation and insulin resistance in rodents. We provide an update on the pathogenesis of adipose tissue inflammation and insulin resistance in obesity and discuss potential mechanisms by which (n-3) PUFA prevent and reverse these changes and the implications in human health. PMID:22332072

Adipocytes impair efficacy of antiretroviral therapy.

PubMed

Couturier, Jacob; Winchester, Lee C; Suliburk, James W; Wilkerson, Gregory K; Podany, Anthony T; Agarwal, Neeti; Xuan Chua, Corrine Ying; Nehete, Pramod N; Nehete, Bharti P; Grattoni, Alessandro; Sastry, K Jagannadha; Fletcher, Courtney V; Lake, Jordan E; Balasubramanyam, Ashok; Lewis, Dorothy E

2018-06-01

Adequate distribution of antiretroviral drugs to infected cells in HIV patients is critical for viral suppression. In humans and primates, HIV- and SIV-infected CD4 T cells in adipose tissues have recently been identified as reservoirs for infectious virus. To better characterize adipose tissue as a pharmacological sanctuary for HIV-infected cells, in vitro experiments were conducted to assess antiretroviral drug efficacy in the presence of adipocytes, and drug penetration in adipose tissue cells (stromal-vascular-fraction cells and mature adipocytes) was examined in treated humans and monkeys. Co-culture experiments between HIV-1-infected CD4 T cells and primary human adipocytes showed that adipocytes consistently reduced the antiviral efficacy of the nucleotide reverse transcriptase inhibitor tenofovir and its prodrug forms tenofovir disoproxil fumarate (TDF) and tenofovir alafenamide (TAF). In HIV-infected persons, LC-MS/MS analysis of intracellular lysates derived from adipose tissue stromal-vascular-fraction cells or mature adipocytes suggested that integrase inhibitors penetrate adipose tissue, whereas penetration of nucleoside/nucleotide reverse transcriptase inhibitors such as TDF, emtricitabine, abacavir, and lamivudine is restricted. The limited distribution and functions of key antiretroviral drugs within fat depots may contribute to viral persistence in adipose tissue. Copyright © 2018 Elsevier B.V. All rights reserved.

Thyroid hormone status defines brown adipose tissue activity and browning of white adipose tissues in mice.

PubMed

Weiner, Juliane; Kranz, Mathias; Klöting, Nora; Kunath, Anne; Steinhoff, Karen; Rijntjes, Eddy; Köhrle, Josef; Zeisig, Vilia; Hankir, Mohammed; Gebhardt, Claudia; Deuther-Conrad, Winnie; Heiker, John T; Kralisch, Susan; Stumvoll, Michael; Blüher, Matthias; Sabri, Osama; Hesse, Swen; Brust, Peter; Tönjes, Anke; Krause, Kerstin

2016-12-12

The present study aimed to determine the effect of thyroid hormone dysfunction on brown adipose tissue activity and white adipose tissue browning in mice. Twenty randomized female C57BL/6NTac mice per treatment group housed at room temperature were rendered hypothyroid or hyperthyroid. In-vivo small animal 18 F-FDG PET/MRI was performed to determine the effects of hypo- and hyperthyroidism on BAT mass and BAT activity. Ex-vivo 14 C-acetate loading assay and assessment of thermogenic gene and protein expression permitted analysis of oxidative and thermogenic capacities of WAT and BAT of eu-, hyper and hypothyroid mice. 18 F-FDG PET/MRI revealed a lack of brown adipose tissue activity in hypothyroid mice, whereas hyperthyroid mice displayed increased BAT mass alongside enhanced 18 F-FDG uptake. In white adipose tissue of both, hyper- and hypothyroid mice, we found a significant induction of thermogenic genes together with multilocular adipocytes expressing UCP1. Taken together, these results suggest that both the hyperthyroid and hypothyroid state stimulate WAT thermogenesis most likely as a consequence of enhanced adrenergic signaling or compensation for impaired BAT function, respectively.

Targeting the NO/superoxide ratio in adipose tissue: relevance to obesity and diabetes management.

PubMed

Jankovic, Aleksandra; Korac, Aleksandra; Buzadzic, Biljana; Stancic, Ana; Otasevic, Vesna; Ferdinandy, Péter; Daiber, Andreas; Korac, Bato

2017-06-01

Insulin sensitivity and metabolic homeostasis depend on the capacity of adipose tissue to take up and utilize excess glucose and fatty acids. The key aspects that determine the fuel-buffering capacity of adipose tissue depend on the physiological levels of the small redox molecule, nitric oxide (NO). In addition to impairment of NO synthesis, excessive formation of the superoxide anion (О 2 •- ) in adipose tissue may be an important interfering factor diverting the signalling of NO and other reactive oxygen and nitrogen species in obesity, resulting in metabolic dysfunction of adipose tissue over time. Besides its role in relief from superoxide burst, enhanced NO signalling may be responsible for the therapeutic benefits of different superoxide dismutase mimetics, in obesity and experimental diabetes models. This review summarizes the role of NO in adipose tissue and highlights the effects of NO/О 2 •- ratio 'teetering' as a promising pharmacological target in the metabolic syndrome. This article is part of a themed section on Redox Biology and Oxidative Stress in Health and Disease. To view the other articles in this section visit http://onlinelibrary.wiley.com/doi/10.1111/bph.v174.12/issuetoc. © 2016 The British Pharmacological Society.

Adipose tissue mitochondrial dysfunction triggers a lipodystrophic syndrome with insulin resistance, hepatosteatosis, and cardiovascular complications.

PubMed

Vernochet, Cecile; Damilano, Federico; Mourier, Arnaud; Bezy, Olivier; Mori, Marcelo A; Smyth, Graham; Rosenzweig, Anthony; Larsson, Nils-Göran; Kahn, C Ronald

2014-10-01

Mitochondrial dysfunction in adipose tissue occurs in obesity, type 2 diabetes, and some forms of lipodystrophy, but whether this dysfunction contributes to or is the result of these disorders is unknown. To investigate the physiological consequences of severe mitochondrial impairment in adipose tissue, we generated mice deficient in mitochondrial transcription factor A (TFAM) in adipocytes by using mice carrying adiponectin-Cre and TFAM floxed alleles. These adiponectin TFAM-knockout (adipo-TFAM-KO) mice had a 75-81% reduction in TFAM in the subcutaneous and intra-abdominal white adipose tissue (WAT) and interscapular brown adipose tissue (BAT), causing decreased expression and enzymatic activity of proteins in complexes I, III, and IV of the electron transport chain (ETC). This mitochondrial dysfunction led to adipocyte death and inflammation in WAT and a whitening of BAT. As a result, adipo-TFAM-KO mice were resistant to weight gain, but exhibited insulin resistance on both normal chow and high-fat diets. These lipodystrophic mice also developed hypertension, cardiac hypertrophy, and cardiac dysfunction. Thus, isolated mitochondrial dysfunction in adipose tissue can lead a syndrome of lipodystrophy with metabolic syndrome and cardiovascular complications. © FASEB.

The Effect of Marine Derived n-3 Fatty Acids on Adipose Tissue Metabolism and Function

PubMed Central

Todorčević, Marijana; Hodson, Leanne

2015-01-01

Adipose tissue function is key determinant of metabolic health, with specific nutrients being suggested to play a role in tissue metabolism. One such group of nutrients are the n-3 fatty acids, specifically eicosapentaenoic acid (EPA; 20:5n-3) and docosahexaenoic acid (DHA; 22:6n-3). Results from studies where human, animal and cellular models have been utilised to investigate the effects of EPA and/or DHA on white adipose tissue/adipocytes suggest anti-obesity and anti-inflammatory effects. We review here evidence for these effects, specifically focusing on studies that provide some insight into metabolic pathways or processes. Of note, limited work has been undertaken investigating the effects of EPA and DHA on white adipose tissue in humans whilst more work has been undertaken using animal and cellular models. Taken together it would appear that EPA and DHA have a positive effect on lowering lipogenesis, increasing lipolysis and decreasing inflammation, all of which would be beneficial for adipose tissue biology. What remains to be elucidated is the duration and dose required to see a favourable effect of EPA and DHA in vivo in humans, across a range of adiposity. PMID:26729182

Adipocytes Impair Efficacy of Antiretroviral Therapy

PubMed Central

Couturier, Jacob; Winchester, Lee C.; Suliburk, James W.; Wilkerson, Gregory K.; Podany, Anthony T.; Agarwal, Neeti; Chua, Corrine Ying Xuan; Nehete, Pramod N.; Nehete, Bharti P.; Grattoni, Alessandro; Sastry, K. Jagannadha; Fletcher, Courtney V.; Lake, Jordan E.; Balasubramanyan, Ashok; Lewis, Dorothy E.

2018-01-01

Adequate distribution of antiretroviral drugs to infected cells in HIV patients is critical for viral suppression. In humans and primates, HIV- and SIV-infected CD4 T cells in adipose tissues have recently been identified as reservoirs for infectious virus. To better characterize adipose tissue as a pharmacological sanctuary for HIV-infected cells, in vitro experiments were conducted to assess antiretroviral drug efficacy in the presence of adipocytes, and drug penetration in adipose tissue cells (stromal-vascular-fraction cells and mature adipocytes) was examined in treated humans and monkeys. Co-culture experiments between HIV-1-infected CD4 T cells and primary human adipocytes showed that adipocytes consistently reduced the antiviral efficacy of the nucleotide reverse transcriptase inhibitor tenofovir and its prodrug forms tenofovir disoproxil fumarate (TDF) and tenofovir alafenamide (TAF). In HIV-infected persons, LC-MS/MS analysis of intracellular lysates derived from adipose tissue stromal-vascular-fraction cells or mature adipocytes suggested that integrase inhibitors penetrate adipose tissue, whereas penetration of nucleoside/nucleotide reverse transcriptase inhibitors such as TDF, emtricitabine, abacavir, and lamivudine is restricted. The limited distribution and functions of key antiretroviral drugs within fat depots may contribute to viral persistence in adipose tissue. PMID:29630975

Brown Adipose Tissue Bioenergetics: A New Methodological Approach

PubMed Central

Calderon‐Dominguez, María; Alcalá, Martín; Sebastián, David; Zorzano, Antonio; Viana, Marta; Serra, Dolors

2017-01-01

The rediscovery of brown adipose tissue (BAT) in humans and its capacity to oxidize fat and dissipate energy as heat has put the spotlight on its potential as a therapeutic target in the treatment of several metabolic conditions including obesity and diabetes. To date the measurement of bioenergetics parameters has required the use of cultured cells or extracted mitochondria with the corresponding loss of information in the tissue context. Herein, we present a method to quantify mitochondrial bioenergetics directly in BAT. Based on XF Seahorse Technology, we assessed the appropriate weight of the explants, the exact concentration of each inhibitor in the reaction, and the specific incubation time to optimize bioenergetics measurements. Our results show that BAT basal oxygen consumption is mostly due to proton leak. In addition, BAT presents higher basal oxygen consumption than white adipose tissue and a positive response to b‐adrenergic stimulation. Considering the whole tissue and not just subcellular populations is a direct approach that provides a realistic view of physiological respiration. In addition, it can be adapted to analyze the effect of potential activators of thermogenesis, or to assess the use of fatty acids or glucose as a source of energy. PMID:28435771

Quantitative monitoring of lipid accumulation over time in cultured adipocytes as function of culture conditions: toward controlled adipose tissue engineering.

PubMed

Or-Tzadikario, Shira; Sopher, Ran; Gefen, Amit

2010-10-01

Adipose tissue engineering is investigated for native fat substitutes and wound healing model systems. Research and clinical applications of bioartificial fat require a quantitative and objective method to continuously measure adipogenesis in living cultures as opposed to currently used culture-destructive techniques that stain lipid droplet (LD) accumulation. To allow standardization, automatic quantification of LD size is further needed, but currently LD size is measured mostly manually. We developed an image processing-based method that does not require staining to monitor adipose cell maturation in vitro nondestructively using optical micrographs taken consecutively during culturing. We employed our method to monitor LD accumulation in 3T3-L1 and mesenchymal stem cells over 37 days. For each cell type, percentage of lipid area, number of droplets per cell, and droplet diameter were obtained every 2-3 days. In 3T3-L1 cultures, high insulin concentration (10 microg/mL) yielded a significantly different (p < 0.01) time course of all three outcome measures. In mesenchymal stem cell cultures, high fetal bovine serum concentration (12.5%) produced significantly more lipid area (p < 0.01). Our method was able to successfully characterize time courses and extents of adipogenesis and is useful for a wide range of applications testing the effects of biochemical, mechanical, and thermal stimulations in tissue engineering of bioartificial fat constructs.

Distribution of volatile branched-chain fatty acids in various lamb tissues.

PubMed

Brennand, C P; Lindsay, R C

1992-01-01

Volatile fatty acids (C4-C11) including even-, odd-, and branched-chain members in lamb tissues were quantitatively analyzed. Volatile branched-chain fatty acids (BCFA) were more concentrated in subcutaneous adipose tissue samples (rump, shoulder, breast) than in perinepheric adipose or muscle tissues. Perinepheric adipose tissue contained relatively high quantities of n-chain, even-numbered fatty acids and very low levels of BCFA. Greater variation existed in fatty acid profiles among similar subcutaneous adipose tissues from different lambs than between samples of adipose tissue from different carcass sites from a given lamb sample. 4-Methyl- and 4-ethyloctanoic acids were present at concentrations greatly above threshold levels in all lamb fats tested, and thus upon hydrolysis would contribute species-related flavors to lamb. 4-Methylnonanoic concentrations in lamb fats ranged from nondetectable to greater than the threshold level, and therefore this compound would not always contribute to the species-related flavors of lamb. Lean meat samples contained very low concentrations of 4-methyl- and 4-ethyloctanoic acids. Copyright © 1992. Published by Elsevier Ltd.

Fat accumulation in the tongue is associated with male gender, abnormal upper airway measures and whole-body adiposity

PubMed Central

Godoy, Ivan R. B.; Martinez-Salazar, Edgar Leonardo; Eajazi, Alireza; Genta, Pedro R.; Bredella, Miriam A.; Torriani, Martin

2017-01-01

Objective To examine associations between tongue adiposity with upper airway measures, whole-body adiposity and gender. We hypothesized that increased tongue adiposity is higher in males and positively associated with abnormal upper airway measures and whole-body adiposity. Methods We studied subjects who underwent whole-body positron emission tomography/computed tomography to obtain tongue attenuation (TA) values and cross-sectional area, pharyngeal length (PL) and mandibular-hyoid distance (MPH), as well as abdominal circumference, abdominal subcutaneous and visceral (VAT) adipose tissue areas, neck circumference (NC) and neck adipose tissue area. Metabolic syndrome was determined from available clinical and laboratory data. Results We identified 206 patients (104 females, 102 males) with mean age 56±17y and mean body mass index (BMI) 28±6kg/m2 (range 16–47kg/m2). Males had lower TA values (P=0.0002) and higher upper airway measures (P< 0.0001) independent of age and BMI (P<0.001). In all subjects, TA was negatively associated with upper airway measures (P<0.001). TA was negatively associated with body composition parameters (all P<0.0001), most notably with VAT (r=−0.53) and NC (r=−0.47). TA values were lower in subjects with metabolic syndrome (P<0.0001). Conclusion Increased tongue adiposity is influenced by gender and is associated with abnormal upper airway patency and body composition parameters. PMID:27733254

Anatomy of the subcutaneous tissue of the trunk and lower extremity.

PubMed

Markman, B; Barton, F E

1987-08-01

Dissections on 8 fresh and 10 embalmed cadavers were used to determine the anatomy of the subcutaneous adipose tissue in the trunk and extremities. These dissections, along with CT scans, confirmed Gray's original description of the subcutaneous tissue consisting of a superficial and deep adipose layer. The superficial adipose layer is contained within organized, compact fascial septa. The deep adipose layer demonstrated regional variations with respect to its fascial framework, but was contained within a relatively loose, less organized, and more widely spaced fascial septa. We observed that the adipose layers are partitioned by a discrete subcutaneous fascia which fuses with the underlying muscle fascia at particular anatomic locations. The deep layer is thus contained by the subcutaneous fascia above and the muscle fascia below to form what we termed the deep adipose compartments. The deep adipose compartments contributed significantly to overall adipose thickness, are bilateral, and are found in the abdomen and paralumbar and gluteal-thigh regions.

Physiological regulation and metabolic role of browning in white adipose tissue.

PubMed

Jankovic, Aleksandra; Otasevic, Vesna; Stancic, Ana; Buzadzic, Biljana; Korac, Aleksandra; Korac, Bato

2017-09-01

Great progress has been made in our understanding of the browning process in white adipose tissue (WAT) in rodents. The recognition that i) adult humans have physiologically inducible brown adipose tissue (BAT) that may facilitate resistance to obesity and ii) that adult human BAT molecularly and functionally resembles beige adipose tissue in rodents, reignited optimism that obesity and obesity-related diabetes type 2 can be battled by controlling the browning of WAT. In this review the main cellular mechanisms and molecular mediators of browning of WAT in different physiological states are summarized. The relevance of browning of WAT in metabolic health is considered primarily through a modulation of biological role of fat tissue in overall metabolic homeostasis.

The evolution of human adiposity and obesity: where did it all go wrong?

PubMed Central

Wells, Jonathan C. K.

2012-01-01

Because obesity is associated with diverse chronic diseases, little attention has been directed to the multiple beneficial functions of adipose tissue. Adipose tissue not only provides energy for growth, reproduction and immune function, but also secretes and receives diverse signaling molecules that coordinate energy allocation between these functions in response to ecological conditions. Importantly, many relevant ecological cues act on growth and physique, with adiposity responding as a counterbalancing risk management strategy. The large number of individual alleles associated with adipose tissue illustrates its integration with diverse metabolic pathways. However, phenotypic variation in age, sex, ethnicity and social status is further associated with different strategies for storing and using energy. Adiposity therefore represents a key means of phenotypic flexibility within and across generations, enabling a coherent life-history strategy in the face of ecological stochasticity. The sensitivity of numerous metabolic pathways to ecological cues makes our species vulnerable to manipulative globalized economic forces. The aim of this article is to understand how human adipose tissue biology interacts with modern environmental pressures to generate excess weight gain and obesity. The disease component of obesity might lie not in adipose tissue itself, but in its perturbation by our modern industrialized niche. Efforts to combat obesity could be more effective if they prioritized ‘external’ environmental change rather than attempting to manipulate ‘internal’ biology through pharmaceutical or behavioral means. PMID:22915021

The evolution of human adiposity and obesity: where did it all go wrong?

PubMed

Wells, Jonathan C K

2012-09-01

Because obesity is associated with diverse chronic diseases, little attention has been directed to the multiple beneficial functions of adipose tissue. Adipose tissue not only provides energy for growth, reproduction and immune function, but also secretes and receives diverse signaling molecules that coordinate energy allocation between these functions in response to ecological conditions. Importantly, many relevant ecological cues act on growth and physique, with adiposity responding as a counterbalancing risk management strategy. The large number of individual alleles associated with adipose tissue illustrates its integration with diverse metabolic pathways. However, phenotypic variation in age, sex, ethnicity and social status is further associated with different strategies for storing and using energy. Adiposity therefore represents a key means of phenotypic flexibility within and across generations, enabling a coherent life-history strategy in the face of ecological stochasticity. The sensitivity of numerous metabolic pathways to ecological cues makes our species vulnerable to manipulative globalized economic forces. The aim of this article is to understand how human adipose tissue biology interacts with modern environmental pressures to generate excess weight gain and obesity. The disease component of obesity might lie not in adipose tissue itself, but in its perturbation by our modern industrialized niche. Efforts to combat obesity could be more effective if they prioritized 'external' environmental change rather than attempting to manipulate 'internal' biology through pharmaceutical or behavioral means.

Gene Expression Signature in Adipose Tissue of Acromegaly Patients

PubMed Central

Hochberg, Irit; Tran, Quynh T.; Barkan, Ariel L.; Saltiel, Alan R.; Chandler, William F.; Bridges, Dave

2015-01-01

To study the effect of chronic excess growth hormone on adipose tissue, we performed RNA sequencing in adipose tissue biopsies from patients with acromegaly (n = 7) or non-functioning pituitary adenomas (n = 11). The patients underwent clinical and metabolic profiling including assessment of HOMA-IR. Explants of adipose tissue were assayed ex vivo for lipolysis and ceramide levels. Patients with acromegaly had higher glucose, higher insulin levels and higher HOMA-IR score. We observed several previously reported transcriptional changes (IGF1, IGFBP3, CISH, SOCS2) that are known to be induced by GH/IGF-1 in liver but are also induced in adipose tissue. We also identified several novel transcriptional changes, some of which may be important for GH/IGF responses (PTPN3 and PTPN4) and the effects of acromegaly on growth and proliferation. Several differentially expressed transcripts may be important in GH/IGF-1-induced metabolic changes. Specifically, induction of LPL, ABHD5, and NRIP1 can contribute to enhanced lipolysis and may explain the elevated adipose tissue lipolysis in acromegalic patients. Higher expression of TCF7L2 and the fatty acid desaturases FADS1, FADS2 and SCD could contribute to insulin resistance. Ceramides were not different between the two groups. In summary, we have identified the acromegaly gene expression signature in human adipose tissue. The significance of altered expression of specific transcripts will enhance our understanding of the metabolic and proliferative changes associated with acromegaly. PMID:26087292

The "Big Bang" in obese fat: Events initiating obesity-induced adipose tissue inflammation.

PubMed

Wensveen, Felix M; Valentić, Sonja; Šestan, Marko; Turk Wensveen, Tamara; Polić, Bojan

2015-09-01

Obesity is associated with the accumulation of pro-inflammatory cells in visceral adipose tissue (VAT), which is an important underlying cause of insulin resistance and progression to diabetes mellitus type 2 (DM2). Although the role of pro-inflammatory cytokines in disease development is established, the initiating events leading to immune cell activation remain elusive. Lean adipose tissue is predominantly populated with regulatory cells, such as eosinophils and type 2 innate lymphocytes. These cells maintain tissue homeostasis through the excretion of type 2 cytokines, such as IL-4, IL-5, and IL-13, which keep adipose tissue macrophages (ATMs) in an anti-inflammatory, M2-like state. Diet-induced obesity is associated with the loss of tissue homeostasis and development of type 1 inflammatory responses in VAT, characterized by IFN-γ. A key event is a shift of ATMs toward an M1 phenotype. Recent studies show that obesity-induced adipocyte hypertrophy results in upregulated surface expression of stress markers. Adipose stress is detected by local sentinels, such as NK cells and CD8(+) T cells, which produce IFN-γ, driving M1 ATM polarization. A rapid accumulation of pro-inflammatory cells in VAT follows, leading to inflammation. In this review, we provide an overview of events leading to adipose tissue inflammation, with a special focus on adipose homeostasis and the obesity-induced loss of homeostasis which marks the initiation of VAT inflammation. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Dioxins and dibenzofurans in adipose tissue of U. S. Vietnam veterans and controls

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kang, H.K.; Watanabe, K.K.; Breen, J.

1990-08-01

Concern about the adverse effects of exposure to Agent Orange is for the most part attributable to its toxic contaminant, 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD). A total of 40 Vietnam veterans, 80 non-Vietnam veterans and 80 civilian men were selected from males born between 1936 and 1954 and their adipose tissues were analyzed for 17 2,3,7,8-substituted dioxins and dibenzofurans. TCDD levels were log normally distributed and the mean level of 2,3,7,8-TCDD in adipose tissue of the Vietnam veterans (13.4 ppt) was not significantly different from that of the non-Vietnam veterans (12.5 ppt) or civilian men (15.8 ppt). Adjusting for demographic variables did notmore » change the conclusions. The study results suggest that heavy exposure to Agent Orange for most Vietnam veterans was very unlikely and that there is no readily available and reliable indirect method of assessing exposure to Agent Orange for Vietnam veterans.« less

Targeted Overexpression of Inducible 6-Phosphofructo-2-kinase in Adipose Tissue Increases Fat Deposition but Protects against Diet-induced Insulin Resistance and Inflammatory Responses*

PubMed Central

Huo, Yuqing; Guo, Xin; Li, Honggui; Xu, Hang; Halim, Vera; Zhang, Weiyu; Wang, Huan; Fan, Yang-Yi; Ong, Kuok Teong; Woo, Shih-Lung; Chapkin, Robert S.; Mashek, Douglas G.; Chen, Yanming; Dong, Hui; Lu, Fuer; Wei, Lai; Wu, Chaodong

2012-01-01

Increasing evidence demonstrates the dissociation of fat deposition, the inflammatory response, and insulin resistance in the development of obesity-related metabolic diseases. As a regulatory enzyme of glycolysis, inducible 6-phosphofructo-2-kinase (iPFK2, encoded by PFKFB3) protects against diet-induced adipose tissue inflammatory response and systemic insulin resistance independently of adiposity. Using aP2-PFKFB3 transgenic (Tg) mice, we explored the ability of targeted adipocyte PFKFB3/iPFK2 overexpression to modulate diet-induced inflammatory responses and insulin resistance arising from fat deposition in both adipose and liver tissues. Compared with wild-type littermates (controls) on a high fat diet (HFD), Tg mice exhibited increased adiposity, decreased adipose inflammatory response, and improved insulin sensitivity. In a parallel pattern, HFD-fed Tg mice showed increased hepatic steatosis, decreased liver inflammatory response, and improved liver insulin sensitivity compared with controls. In both adipose and liver tissues, increased fat deposition was associated with lipid profile alterations characterized by an increase in palmitoleate. Additionally, plasma lipid profiles also displayed an increase in palmitoleate in HFD-Tg mice compared with controls. In cultured 3T3-L1 adipocytes, overexpression of PFKFB3/iPFK2 recapitulated metabolic and inflammatory changes observed in adipose tissue of Tg mice. Upon treatment with conditioned medium from iPFK2-overexpressing adipocytes, mouse primary hepatocytes displayed metabolic and inflammatory responses that were similar to those observed in livers of Tg mice. Together, these data demonstrate a unique role for PFKFB3/iPFK2 in adipocytes with regard to diet-induced inflammatory responses in both adipose and liver tissues. PMID:22556414

Lean phenotype and resistance to diet-induced obesity in vitamin D receptor knockout mice correlates with induction of uncoupling protein-1 in white adipose tissue.

PubMed

Narvaez, Carmen J; Matthews, Donald; Broun, Emily; Chan, Michelle; Welsh, JoEllen

2009-02-01

Increased adiposity is a feature of aging in both mice and humans, but the molecular mechanisms underlying age-related changes in adipose tissue stores remain unclear. In previous studies, we noted that 18-month-old normocalcemic vitamin D receptor (VDR) knockout (VDRKO) mice exhibited atrophy of the mammary adipose compartment relative to wild-type (WT) littermates, suggesting a role for VDR in adiposity. Here we monitored body fat depots, food intake, metabolic factors, and gene expression in WT and VDRKO mice on the C57BL6 and CD1 genetic backgrounds. Regardless of genetic background, both sc and visceral white adipose tissue depots were smaller in VDRKO mice than WT mice. The lean phenotype of VDRKO mice was associated with reduced serum leptin and compensatory increased food intake. Similar effects on adipose tissue, leptin and food intake were observed in mice lacking Cyp27b1, the 1alpha-hydroxylase enzyme that generates 1,25-dihydroxyvitamin D(3), the VDR ligand. Although VDR ablation did not reduce expression of peroxisome proliferator-activated receptor-gamma or fatty acid synthase, PCR array screening identified several differentially expressed genes in white adipose tissue from WT and VDRKO mice. Uncoupling protein-1, which mediates dissociation of cellular respiration from energy production, was greater than 25-fold elevated in VDRKO white adipose tissue. Consistent with elevation in uncoupling protein-1, VDRKO mice were resistant to high-fat diet-induced weight gain. Collectively, these studies identify a novel role for 1,25-dihydroxyvitamin D(3) and the VDR in the control of adipocyte metabolism and lipid storage in vivo.

Analysis of type II diabetes mellitus adipose-derived stem cells for tissue engineering applications

PubMed Central

Minteer, Danielle Marie; Young, Matthew T; Lin, Yen-Chih; Over, Patrick J; Rubin, J Peter; Gerlach, Jorg C

2015-01-01

To address the functionality of diabetic adipose-derived stem cells in tissue engineering applications, adipose-derived stem cells isolated from patients with and without type II diabetes mellitus were cultured in bioreactor culture systems. The adipose-derived stem cells were differentiated into adipocytes and maintained as functional adipocytes. The bioreactor system utilizes a hollow fiber–based technology for three-dimensional perfusion of tissues in vitro, creating a model in which long-term culture of adipocytes is feasible, and providing a potential tool useful for drug discovery. Daily metabolic activity of the adipose-derived stem cells was analyzed within the medium recirculating throughout the bioreactor system. At experiment termination, tissues were extracted from bioreactors for immunohistological analyses in addition to gene and protein expression. Type II diabetic adipose-derived stem cells did not exhibit significantly different glucose consumption compared to adipose-derived stem cells from patients without type II diabetes (p > 0.05, N = 3). Expression of mature adipocyte genes was not significantly different between diabetic/non-diabetic groups (p > 0.05, N = 3). Protein expression of adipose tissue grown within all bioreactors was verified by Western blotting.The results from this small-scale study reveal adipose-derived stem cells from patients with type II diabetes when removed from diabetic environments behave metabolically similar to the same cells of non-diabetic patients when cultured in a three-dimensional perfusion bioreactor, suggesting that glucose transport across the adipocyte cell membrane, the hindrance of which being characteristic of type II diabetes, is dependent on environment. The presented observation describes a tissue-engineered tool for long-term cell culture and, following future adjustments to the culture environment and increased sample sizes, potentially for anti-diabetic drug testing. PMID:26090087

Environmental Chemicals Modulate Polar Bear (Ursus maritimus) Peroxisome Proliferator-Activated Receptor Gamma (PPARG) and Adipogenesis in Vitro.

PubMed

Routti, Heli; Lille-Langøy, Roger; Berg, Mari K; Fink, Trine; Harju, Mikael; Kristiansen, Kurt; Rostkowski, Pawel; Rusten, Marte; Sylte, Ingebrigt; Øygarden, Lene; Goksøyr, Anders

2016-10-04

We studied interactions between polar bear peroxisome proliferator-activated receptor gamma (pbPPARG) and selected compounds using a luciferase reporter assay and predictions through molecular docking. Furthermore, we studied adipogenesis by liver and adipose tissue extracts from a polar bear and three synthetic mixtures of contaminants in murine 3T3-L1 preadipocytes and polar bear adipose tissue-derived stem cells (pbASCs). PCB153 and p,p'-DDE antagonized pbPPARG, although their predicted receptor-ligand affinity was weak. PBDEs, tetrabromobisphenol A, and PCB170 had a weak agonistic effect on pbPPARG, while hexabromocyclododecane, bisphenol A, oxychlordane, and endosulfan were weak antagonists. pbPPARG-mediated luciferase activity was suppressed by synthetic contaminant mixtures reflecting levels measured in polar bear adipose tissue, as were transcript levels of PPARG and the PPARG target gene fatty acid binding protein 4 (FABP4) in pbASCs. Contaminant extracts from polar bear tissues enhanced triglyceride accumulation in murine 3T3-L1 cells and pbASCs, whereas triglyceride accumulation was not affected by the synthetic mixtures. Chemical characterization of extracts using nontarget methods revealed presence of exogenous compounds that have previously been reported to induce adipogenesis. These compounds included phthalates, tonalide, and nonylphenol. In conclusion, major legacy contaminants in polar bear adipose tissue exert antagonistic effects on PPARG, but adipogenesis by a mixture containing emerging compounds may be enhanced through PPARG or other pathways.

MECHANISMS IN ENDOCRINOLOGY: Skeletal muscle lipotoxicity in insulin resistance and type 2 diabetes: a causal mechanism or an innocent bystander?

PubMed

Brøns, Charlotte; Grunnet, Louise Groth

2017-02-01

Dysfunctional adipose tissue is associated with an increased risk of developing type 2 diabetes (T2D). One characteristic of a dysfunctional adipose tissue is the reduced expandability of the subcutaneous adipose tissue leading to ectopic storage of fat in organs and/or tissues involved in the pathogenesis of T2D that can cause lipotoxicity. Accumulation of lipids in the skeletal muscle is associated with insulin resistance, but the majority of previous studies do not prove any causality. Most studies agree that it is not the intramuscular lipids per se that causes insulin resistance, but rather lipid intermediates such as diacylglycerols, fatty acyl-CoAs and ceramides and that it is the localization, composition and turnover of these intermediates that play an important role in the development of insulin resistance and T2D. Adipose tissue is a more active tissue than previously thought, and future research should thus aim at examining the exact role of lipid composition, cellular localization and the dynamics of lipid turnover on the development of insulin resistance. In addition, ectopic storage of fat has differential impact on various organs in different phenotypes at risk of developing T2D; thus, understanding how adipogenesis is regulated, the interference with metabolic outcomes and what determines the capacity of adipose tissue expandability in distinct population groups is necessary. This study is a review of the current literature on the adipose tissue expandability hypothesis and how the following ectopic lipid accumulation as a consequence of a limited adipose tissue expandability may be associated with insulin resistance in muscle and liver. © 2017 European Society of Endocrinology.

Ontogenesis of muscle and adipose tissues and their interactions in ruminants and other species.

PubMed

Bonnet, M; Cassar-Malek, I; Chilliard, Y; Picard, B

2010-07-01

The lean-to-fat ratio, that is, the relative masses of muscle and adipose tissue, is a criterion for the yield and quality of bovine carcasses and meat. This review describes the interactions between muscle and adipose tissue (AT) that may regulate the dynamic balance between the number and size of muscle v. adipose cells. Muscle and adipose tissue in cattle grow by an increase in the number of cells (hyperplasia), mainly during foetal life. The total number of muscle fibres is set by the end of the second trimester of gestation. By contrast, the number of adipocytes is never set. Number of adipocytes increases mainly before birth until 1 year of age, depending on the anatomical location of the adipose tissue. Hyperplasia concerns brown pre-adipocytes during foetal life and white pre-adipocytes from a few weeks after birth. A decrease in the number of secondary myofibres and an increase in adiposity in lambs born from mothers severely underfed during early pregnancy suggest a balance in the commitment of a common progenitor into the myogenic or adipogenic lineages, or a reciprocal regulation of the commitment of two distinct progenitors. The developmental origin of white adipocytes is a subject of debate. Molecular and histological data suggested a possible transdifferentiation of brown into white adipocytes, but this hypothesis has now been challenged by the characterization of distinct precursor cells for brown and white adipocytes in mice. Increased nutrient storage in fully differentiated muscle fibres and adipocytes, resulting in cell enlargement (hypertrophy), is thought to be the main mechanism, whereby muscle and fat masses increase in growing cattle. Competition or prioritization between adipose and muscle cells for the uptake and metabolism of nutrients is suggested, besides the successive waves of growth of muscle v. adipose tissue, by the inhibited or delayed adipose tissue growth in bovine genotypes exhibiting strong muscular development. This competition or prioritization occurs through cellular signalling pathways and the secretion of proteins by adipose tissue (adipokines) and muscle (myokines), putatively regulating their hypertrophy in a reciprocal manner. Further work on the mechanisms underlying cross-talk between brown or white adipocytes and muscle fibres will help to achieve better understanding as a prerequisite to improving the control of body growth and composition in cattle.

Alterations in fatty acid metabolism in response to obesity surgery combined with dietary counseling

PubMed Central

Walle, P; Takkunen, M; Männistö, V; Vaittinen, M; Käkelä, P; Ågren, J; Schwab, U; Lindström, J; Tuomilehto, J; Uusitupa, M; Pihlajamäki, J

2017-01-01

Background: The effects of obesity surgery on serum and adipose tissue fatty acid (FA) profile and FA metabolism may modify the risk of obesity-related diseases. Methods: We measured serum (n=122) and adipose tissue (n=24) FA composition and adipose tissue mRNA expression of genes regulating FA metabolism (n=100) in participants of the Kuopio Obesity Surgery Study (KOBS, age 47.2±8.7 years, BMI 44.6±6.0, 40 men, 82 women) before and one year after obesity surgery. As part of the surgery protocol, all the subjects were instructed to add sources of unsaturated fatty acids, such as rapeseed oil and fatty fish, into their diet. The results were compared with changes in serum FA composition in 122 subjects from the Finnish Diabetes Prevention study (DPS) (age 54.3±7.1 years, BMI 32.2±4.6, 28 men, 94 women). Results: The proportion of saturated FAs decreased and the proportion of n-3 and n-6 FAs increased in serum triglycerides after obesity surgery (all P<0.002). Weight loss predicted changes in quantitative amounts of saturated FAs, monounsaturated FAs, n-3 and n-6 FAs in triglycerides (P<0.002 for all). Moreover, the changes in adipose tissue FAs reflected the changes in serum FAs, and some of the changes were associated with mRNA expression of elongases and desaturases in adipose tissue (all P<0.05). In line with this the estimated activity of elongase (18:1 n-7/16:1 n-7) increased significantly after obesity surgery in all lipid fractions (all P<4 × 10−7) and the increase in the estimated activity of D5D in triglycerides was associated with higher weight loss (r=0.415, P<2 × 10−6). Changes in serum FA profile were similar after obesity surgery and lifestyle intervention, except for the change in the absolute amounts of n-3 FAs between the two studies (P=0.044). Conclusions: Beneficial changes in serum and adipose tissue FAs after obesity surgery could be associated with changes in endogenous metabolism and diet. PMID:28869586

Diet and adipose tissue distributions: The Multi-Ethnic Study of Atherosclerosis

USDA-ARS?s Scientific Manuscript database

Dietary quality affects cardiometabolic risk, yet its pathways of influence on regional adipose tissue depots involved in metabolic and diabetes risk are not well established. We aimed to investigate the relationship between dietary quality and regional adiposity. We investigated 5079 individuals in...

Polychlorinated biphenyls and polybrominated biphenyl ethers in adipose tissue and matched serum from an E-waste recycling area (Wenling, China).

PubMed

Lv, Quan-Xia; Wang, Wenyue; Li, Xing-Hong; Yu, Lianlian; Zhang, Yun; Tian, Yuan

2015-04-01

To Date, the knowledge on relationship between PCBs/PBDEs exposure and thyroid hormones (THs) levels during pregnancy still needs to be extended. Meanwhile, studies on congener-specific adipose-serum ratios for PCBs/PBDEs were limited. This study reports the levels of PCBs/PBDEs in serum-adipose tissue samples (n = 64) from expectant women living surrounding e-waste recycling sites in Wenling, China. Their concentrations varied from several to hundreds of ng g(-1) lipid. Maternal exposure to PCBs was associated with lower TSH during pregnancy, suggesting possible implication for maternal health and fetal development. The compound levels between the adipose tissue and matched serum samples were highly correlated (p < 0.001), generating a predicted adipose-serum partitioning relationship for individual PCB congener and PBDE congener. Molecular characteristics, such as Kow value, molecular weight and molecular volume, may play a key role in the variable partitioning of some compounds between serum and adipose tissue. Copyright © 2015 Elsevier Ltd. All rights reserved.

Feeding feedlot steers fish oil alters the fatty acid composition of adipose and muscle tissue.

PubMed

Wistuba, T J; Kegley, E B; Apple, J K; Rule, D C

2007-10-01

Sixteen steers (441±31.7kg initial body weight) consumed two high concentrate diets with either 0 or 3% fish oil to determine the impact of fish oil, an omega-3 fatty acid source, on the fatty acid composition of beef carcasses. Collected tissue samples included the Longissimus thoracis from the 6th to 7th rib section, ground 10th to 12th rib, liver, subcutaneous adipose tissue adjacent to the 12th rib, intramuscular adipose tissue in the 6th to 7th rib sections, perirenal adipose tissue, and brisket adipose tissue. Including fish oil in the diet increased most of the saturated fatty acids (P<0.01) and proportions of polyunsaturated fatty acids (P<0.06), and decreased (P<0.01) proportions of monounsaturated fatty acids. Dietary fish oil increased (P<0.01) levels of omega-3 fatty acids in sampled tissues, resulting in lower (P<0.01) omega-6:omega-3 ratios. The weight percentages of C20:5 and C22:6 in tissue may provide the recommended daily allowance for humans. Fish oil may have a role in beef niche marketing if there are no deleterious effects on consumer satisfaction.

Ginsenoside Rg1 and platelet-rich fibrin enhance human breast adipose-derived stem cells function for soft tissue regeneration

PubMed Central

Li, Hong-Mian; Peng, Qi-Liu; Huang, Min-Hong; Li, De-Quan; Liang, Yi-Dan; Chi, Gang-Yi; Li, De-Hui; Yu, Bing-Chao; Huang, Ji-Rong

2016-01-01

Adipose-derived stem cells (ASCs) can be used to repair soft tissue defects, wounds, burns, and scars and to regenerate various damaged tissues. The cell differentiation capacity of ASCs is crucial for engineered adipose tissue regeneration in reconstructive and plastic surgery. We previously reported that ginsenoside Rg1 (G-Rg1 or Rg1) promotes proliferation and differentiation of ASCs in vitro and in vivio. Here we show that both G-Rg1 and platelet-rich fibrin (PRF) improve the proliferation, differentiation, and soft tissue regeneration capacity of human breast adipose-derived stem cells (HBASCs) on collagen type I sponge scaffolds in vitro and in vivo. Three months after transplantation, tissue wet weight, adipocyte number, intracellular lipid, microvessel density, and gene and protein expression of VEGF, HIF-1α, and PPARγ were higher in both G-Rg1- and PRF-treated HBASCs than in control grafts. More extensive new adipose tissue formation was evident after treatment with G-Rg1 or PRF. In summary, G-Rg1 and/or PRF co-administration improves the function of HBASCs for soft tissue regeneration engineering. PMID:27191987

Adipose-derived Mesenchymal Stem Cells and Their Reparative Potential in Ischemic Heart Disease.

PubMed

Badimon, Lina; Oñate, Blanca; Vilahur, Gemma

2015-07-01

Adipose tissue has long been considered an energy storage and endocrine organ; however, in recent decades, this tissue has also been considered an abundant source of mesenchymal cells. Adipose-derived stem cells are easily obtained, show a strong capacity for ex vivo expansion and differentiation to other cell types, release a large variety of angiogenic factors, and have immunomodulatory properties. Thus, adipose tissue is currently the focus of considerable interest in the field of regenerative medicine. In the context of coronary heart disease, numerous experimental studies have supported the safety and efficacy of adipose-derived stem cells in the setting of myocardial infarction. These results have encouraged the clinical use of these stem cells, possibly prematurely. Indeed, the presence of cardiovascular risk factors, such as hypertension, coronary disease, diabetes mellitus, and obesity, alter and reduce the functionality of adipose-derived stem cells, putting in doubt the efficacy of their autologous implantation. In the present article, white adipose tissue is described, the stem cells found in this tissue are characterized, and the use of these cells is discussed according to the preclinical and clinical trials performed so far. Copyright © 2015 Sociedad Española de Cardiología. Published by Elsevier España, S.L.U. All rights reserved.

Insulin Resistance in Adipose Tissue but Not in Liver Is Associated with Aortic Valve Calcification.

PubMed

Jorge-Galarza, Esteban; Posadas-Romero, Carlos; Torres-Tamayo, Margarita; Medina-Urrutia, Aida X; Rodas-Díaz, Marco A; Posadas-Sánchez, Rosalinda; Vargas-Alarcón, Gilberto; González-Salazar, María Del Carmen; Cardoso-Saldaña, Guillermo C; Juárez-Rojas, Juan G

2016-01-01

Background . Insulin resistance is involved in the pathogenesis of cardiovascular disease, but its relationship with cardiovascular calcification has yielded conflicting results. The purpose of the present study was to investigate the role of hepatic and adipose tissue insulin resistance on the presence of coronary artery (CAC > 0) and aortic valve calcification (AVC > 0). Methods . In 1201 subjects (52% women, 53.6 ± 9.3 years old) without familiar and personal history of coronary heart disease, CAC and AVC were assessed by multidetector-computed tomography. Cardiovascular risk factors were documented and lipid profile, inflammation markers, glucose, insulin, and free fatty acids were measured. Hepatic insulin resistance (HOMA-IR) and adipose tissue insulin resistance (Adipo-IR) indices were calculated. Results . There was a significant relationship between HOMA-IR and Adipo-IR indices ( r = 0.758, p < 0.001). Participants in the highest quartiles of HOMA-IR and Adipo-IR indices had a more adverse cardiovascular profile and higher prevalence of CAC > 0 and AVC > 0. After full adjustment, subjects in the highest quartile of Adipo-IR index had higher odds of AVC > 0 (OR: 2.40; 95% CI: 1.30-4.43), as compared to those in the lowest quartile. Conclusions . Adipo-IR was independently associated with AVC > 0. This suggests that abnormal adipose tissue function favors insulin resistance that may promote the development and progression of AVC.

Adipose-derived stromal cells for the reconstruction of a human vesical equivalent.

PubMed

Rousseau, Alexandre; Fradette, Julie; Bernard, Geneviève; Gauvin, Robert; Laterreur, Véronique; Bolduc, Stéphane

2015-11-01

Despite a wide panel of tissue-engineering models available for vesical reconstruction, the lack of a differentiated urothelium remains their main common limitation. For the first time to our knowledge, an entirely human vesical equivalent, free of exogenous matrix, has been reconstructed using the self-assembly method. Moreover, we tested the contribution of adipose-derived stromal cells, an easily available source of mesenchymal cells featuring many potential advantages, by reconstructing three types of equivalent, named fibroblast vesical equivalent, adipose-derived stromal cell vesical equivalent and hybrid vesical equivalent--the latter containing both adipose-derived stromal cells and fibroblasts. The new substitutes have been compared and characterized for matrix composition and organization, functionality and mechanical behaviour. Although all three vesical equivalents displayed adequate collagen type I and III expression, only two of them, fibroblast vesical equivalent and hybrid vesical equivalent, sustained the development of a differentiated and functional urothelium. The presence of uroplakins Ib, II and III and the tight junction marker ZO-1 was detected and correlated with impermeability. The mechanical resistance of these tissues was sufficient for use by surgeons. We present here in vitro tissue-engineered vesical equivalents, built without the use of any exogenous matrix, able to sustain mechanical stress and to support the formation of a functional urothelium, i.e. able to display a barrier function similar to that of native tissue. Copyright © 2013 John Wiley & Sons, Ltd.

Human adipose-derived stem cells promote vascularization of collagen-based scaffolds transplanted into nude mice

PubMed Central

Cherubino, Mario; Valdatta, Luigi; Balzaretti, Riccardo; Pellegatta, Igor; Rossi, Federica; Protasoni, Marina; Tedeschi, Alessandra; Accolla, Roberto S; Bernardini, Giovanni; Gornati, Rosalba

2016-01-01

Aim: After in vivo implantation of cell-loaded devices, only the cells close to the capillaries can obtain nutrients to maintain their functions. It is known that factors secreted by stem cells, rather than stem cells themselves, are fundamental to guarantee new vascularization in the area of implant. Materials & methods: To investigate this possibility, we have grafted mice with Bilayer and Flowable Integra® scaffolds, loaded or not with human adipose-derived stem cells. Results: Our results support the therapeutic potential of human adipose-derived stem cells to induce new vascular networks of engineered organs and tissues. Conclusion: This finding suggests that our approach can help to form new vascular networks that allow sufficient vascularization of engineered organs and tissues in cases of difficult wound healing due to ischemic conditions. PMID:26965659

Enhanced glycogen metabolism in adipose tissue decreases triglyceride mobilization

PubMed Central

Markan, Kathleen R.; Jurczak, Michael J.; Allison, Margaret B.; Ye, Honggang; Sutanto, Maria M.; Cohen, Ronald N.

2010-01-01

Adipose tissue is a primary site for lipid storage containing trace amounts of glycogen. However, refeeding after a prolonged partial fast produces a marked transient spike in adipose glycogen, which dissipates in coordination with the initiation of lipid resynthesis. To further study the potential interplay between glycogen and lipid metabolism in adipose tissue, the aP2-PTG transgenic mouse line was utilized since it contains a 100- to 400-fold elevation of adipocyte glycogen levels that are mobilized upon fasting. To determine the fate of the released glucose 1-phosphate, a series of metabolic measurements were made. Basal and isoproterenol-stimulated lactate production in vitro was significantly increased in adipose tissue from transgenic animals. In parallel, basal and isoproterenol-induced release of nonesterified fatty acids (NEFAs) was significantly reduced in transgenic adipose tissue vs. control. Interestingly, glycerol release was unchanged between the genotypes, suggesting that enhanced triglyceride resynthesis was occurring in the transgenic tissue. Qualitatively similar results for NEFA and glycerol levels between wild-type and transgenic animals were obtained in vivo during fasting. Additionally, the physiological upregulation of the phosphoenolpyruvate carboxykinase cytosolic isoform (PEPCK-C) expression in adipose upon fasting was significantly blunted in transgenic mice. No changes in whole body metabolism were detected through indirect calorimetry. Yet weight loss following a weight gain/loss protocol was significantly impeded in the transgenic animals, indicating a further impairment in triglyceride mobilization. Cumulatively, these results support the notion that the adipocyte possesses a set point for glycogen, which is altered in response to nutritional cues, enabling the coordination of adipose glycogen turnover with lipid metabolism. PMID:20424138

Vitamin D deficiency decreases adiposity in rats and causes altered expression of uncoupling proteins and steroid receptor coactivator3.

PubMed

Bhat, Mehrajuddin; Noolu, Bindu; Qadri, Syed S Y H; Ismail, Ayesha

2014-10-01

The vitamin D endocrine system is functional in the adipose tissue, as demonstrated in vitro, in cultured adipocytes, and in vivo in mutant mice that developed altered lipid metabolism and fat storage in the absence of either 1,25-dihydroxyvitamin D3 [1,25(OH)2D3] or the vitamin D receptor. The aim of the present study was to examine the role of vitamin D and calcium on body adiposity in a diet-induced vitamin D deficient rat model. Vitamin D-deficient rats gained less weight and had lower amounts of visceral fat. Consistent with reduced adipose tissue mass, the vitamin D-deficient rats had low circulating levels of leptin, which reflects body fat stores. Expression of vitamin D and calcium sensing receptors, and that of genes involved in adipogenesis such as peroxisome proliferator-activated receptor, fatty acid synthase and leptin were significantly reduced in white adipose tissue of deficient rats compared to vitamin D-sufficient rats. Furthermore, the expression of uncoupling proteins (Ucp1 and Ucp2) was elevated in the white adipose tissue of the deficient rat indicative of higher energy expenditure, thereby leading to a lean phenotype. Expression of the p160 steroid receptor coactivator3 (SRC3), a key regulator of adipogenesis in white adipose tissue was decreased in vitamin D-deficient state. Interestingly, most of the changes observed in vitamin D deficient rats were corrected by calcium supplementation alone. Our data demonstrates that dietary vitamin D and calcium regulate adipose tissue function and metabolism. Copyright © 2014 Elsevier Ltd. All rights reserved.

Lipoprotein lipase regulation by insulin and glucocorticoid in subcutaneous and omental adipose tissues of obese women and men.

PubMed Central

Fried, S K; Russell, C D; Grauso, N L; Brolin, R E

1993-01-01

There are marked variations in the activity of lipoprotein lipase (LPL) among adipose depots, particularly in women. Consistent with data on LPL activity, the level of expression of LPL mRNA was lower in omental (OM) than subcutaneous (SQ) adipose tissue of women. To investigate the cellular basis of these differences, OM and SQ adipose tissues obtained at surgery from obese men and women were placed in organ culture for 7 d with varying concentrations of insulin and dexamethasone. Insulin increased levels of LPL mRNA and LPL activity in abdominal SQ but not OM adipose tissue. Dexamethasone also increased LPL mRNA and LPL activity, and these effects were more marked in the OM adipose tissue, particularly in men. When insulin and dexamethasone were added together, synergistic increases in LPL activity were seen in both depots, and this was in part explained at the level of LPL mRNA. The SQ depot was more sensitive to the effects of submaximal doses of dexamethasone in the presence of insulin. The maximum activity of LPL induced by insulin or insulin plus dexamethasone was higher in the SQ than in the OM depot of women, and this was associated with higher levels of LPL mRNA. Rates of LPL synthesis paralleled LPL mRNA levels. These data show that insulin and glucocorticoids influence human adipose tissue LPL activity at the level of LPL gene expression, as well as posttranslationally, and that responsiveness to these hormonal effects is dependent on adipose depot and gender. Images PMID:8227334

Augmented expression and secretion of adipose-derived pigment epithelium-derived factor does not alter local angiogenesis or contribute to the development of systemic metabolic derangements.

PubMed

Lakeland, Thomas V; Borg, Melissa L; Matzaris, Maria; Abdelkader, Amany; Evans, Roger G; Watt, Matthew J

2014-06-15

Impaired coupling of adipose tissue expansion and vascularization is proposed to lead to adipocyte hypoxia and inflammation, which in turn contributes to systemic metabolic derangements. Pigment epithelium-derived factor (PEDF) is a powerful antiangiogenic factor that is secreted by adipocytes, elevated in obesity, and implicated in the development of insulin resistance. We explored the angiogenic and metabolic role of adipose-derived PEDF through in vivo studies of mice with overexpression of PEDF in adipocytes (PEDF-aP2). PEDF expression in white adipocytes and PEDF secretion from adipose tissue was increased in transgenic mice, but circulating levels of PEDF were not increased. Overexpression of PEDF did not alter vascularization, the partial pressure of O2, cellular hypoxia, or gene expression of inflammatory markers in adipose tissue. Energy expenditure and metabolic substrate utilization, body mass, and adiposity were not altered in PEDF-aP2 mice. Whole body glycemic control was normal as assessed by glucose and insulin tolerance tests, and adipocyte-specific glucose uptake was unaffected by PEDF overexpression. Adipocyte lipolysis was increased in PEDF-aP2 mice and associated with increased adipose triglyceride lipase and decreased perilipin 1 expression. Experiments conducted in mice rendered obese by high-fat feeding showed no differences between PEDF-aP2 and wild-type mice for body mass, adiposity, whole body energy expenditure, glucose tolerance, or adipose tissue oxygenation. Together, these data indicate that adipocyte-generated PEDF enhances lipolysis but question the role of PEDF as a major antiangiogenic or proinflammatory mediator in adipose tissue in vivo. Copyright © 2014 the American Physiological Society.

Expression profiles and associations of adiponectin and adiponectin receptors with intramuscular fat in Tibetan chicken.

PubMed

Zhang, R; Lin, Y; Zhi, L; Liao, H; Zuo, L; Li, Z; Xu, Y

2017-04-01

1. Adiponectin and its receptors (ADIPOR1 and ADIPOR2) are novel endocrine systems that act at various levels to modulate glucose and lipid metabolism. This study was designed to investigate the spatial expression of adiponectin, ADIPOR1 and ADIPOR2 genes in various tissues in Tibetan chicken. The temporal expression of adiponectin and its receptor mRNAs were also studied in adipose tissue, breast muscle and thigh muscle and the correlations of the levels of adiponectin, ADIPOR1 and ADIPOR2 mRNA with the contents of intramuscular fat in breast muscle and thigh muscle of Tibetan chicken were determined. 2. Quantitative real-time PCR detected chicken adiponectin, ADIPOR1 and ADIPOR2 mRNA transcripts in heart, liver, spleen, lung, kidney, skeletal muscle and adipose tissue. 3. Adipose tissue contained the highest amount of adiponectin mRNA followed by the kidney and liver. The expression levels of ADIPOR1 mRNA were significantly higher in adipose tissue, lung and spleen, and adipose tissue exhibited significantly higher levels of ADIPOR2 mRNA followed by the spleen and lung compared with other tissues. 4. Temporal expression profiles of adiponectin, ADIPOR1 and ADIPOR2 mRNA showed gender differences in adipose tissue and skeletal muscle at certain ages. In adipose tissue, adiponectin mRNA was higher in 154-d-old females and ADIPOR1 mRNA was higher in 154-d-old males: Adiponectin and ADIPOR2 mRNA were higher, and ADIPOR1 mRNA was lower, in thigh muscle in female compared with male chickens. 5. The correlation data showed that, except for adiponectin mRNA, the levels of ADIPOR1 and ADIPOR2 mRNA in thigh muscle of males were significantly positively correlated with IMF (r = 0.206 for the ADIPOR1 gene and r = 0.676 for the ADIPOR2 gene). 6. Taken together, it was concluded that adiponectin and the ADIPOR1 and ADIPOR2 genes are ubiquitously expressed in various tissues of Tibetan chicken and the expression of the adiponectin system is gender-dependant at certain ages in adipose tissue and skeletal muscle.

Insulin signaling, inflammation, and lipolysis in subcutaneous adipose tissue of transition dairy cows either overfed energy during the prepartum period or fed a controlled-energy diet.

PubMed

Mann, S; Nydam, D V; Abuelo, A; Leal Yepes, F A; Overton, T R; Wakshlag, J J

2016-08-01

Adipose tissue mobilization is a hallmark of the transition period in dairy cows. Cows overfed energy during the dry period have higher concentrations of nonesterified fatty acids (NEFA) and β-hydroxybutyrate (BHB) compared with cows fed a controlled-energy diet prepartum. The reason for an increase in blood NEFA concentrations at the level of adipose tissue in cows overfed energy has not been fully elucidated. One hypothesis is that cows with high BHB concentrations suffer from adipose tissue-specific insulin resistance, leading to higher rates of adipose tissue mobilization in the postpartum period. To test this hypothesis, subcutaneous adipose tissue biopsies of cows overfed energy in excess of predicted requirements by 50% in the dry period, and that had high concentrations of blood BHB postpartum (group H; n=12), were used. Findings were compared with results of biopsies from cows fed a controlled-energy diet and with low BHB concentrations postpartum (group C; n=12) to create the biggest contrast in BHB concentrations. Subcutaneous adipose tissue biopsies were obtained before and 60 min after an intravenous glucose challenge (0.25 g/kg of glucose) at 28 and 10 d before expected calving as well as on d 4 and 21 postpartum. Phosphorylation of protein kinase B, extracellular signal-regulated kinase, and hormone-sensitive lipase was determined before and after glucose infusion by Western blot. Western blot was also used to assess the baseline protein abundance of peroxisome proliferator-activated receptor gamma and insulin receptor β-subunit. In addition, gene expression of fatty acid synthase, adiponectin, monocyte chemoattractant protein 1, and tumor necrosis factor α was determined by real-time quantitative reverse-transcription PCR. Backfat thickness was determined in the thurl area by ultrasonography. Cows in group H showed a greater degree of lipogenesis prepartum, but no differences were found in lipolytic enzyme activity postpartum compared with cows in group C. Baseline plasma insulin concentrations were decreased and serum NEFA concentrations increased postpartum in group H. Insulin signaling through protein kinase B, quantity of insulin receptor, markers of inflammation, and peroxisome proliferator-activated receptor gamma in adipose tissue were not different between the groups, but expression of adiponectin was increased in adipose tissue of cows in group H during the immediate peripartum period. In conclusion, differences in serum concentrations of NEFA between cows overfed energy prepartum and high blood concentrations of BHB are likely due to greater negative energy balance postpartum reflected in lower circulating concentrations of glucose and insulin and an increase in the total amount of mobilized adipose tissue mass rather than due to changes in adipose tissue insulin signaling. Copyright © 2016 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

A Novel Biological Approach to Treat Chondromalacia Patellae

PubMed Central

Lee, Sang Hee

2013-01-01

Mesenchymal stem cells from several sources (bone marrow, synovial tissue, cord blood, and adipose tissue) can differentiate into variable parts (bones, cartilage, muscle, and adipose tissue), representing a promising new therapy in regenerative medicine. In animal models, mesenchymal stem cells have been used successfully to regenerate cartilage and bones. However, there have been no follow-up studies on humans treated with adipose-tissue-derived stem cells (ADSCs) for the chondromalacia patellae. To obtain ADSCs, lipoaspirates were obtained from lower abdominal subcutaneous adipose tissue. The stromal vascular fraction was separated from the lipoaspirates by centrifugation after treatment with collagenase. The stem-cell-containing stromal vascular fraction was mixed with calcium chloride-activated platelet rich plasma and hyaluronic acid, and this ADSCs mixture was then injected under ultrasonic guidance into the retro-patellar joints of all three patients. Patients were subjected to pre- and post-treatment magnetic resonance imaging (MRI) scans. Pre- and post-treatment subjective pain scores and physical therapy assessments measured clinical changes. One month after the injection of autologous ADSCs, each patient's pain improved 50–70%. Three months after the treatment, the patients' pain improved 80–90%. The pain improvement persisted over 1 year, confirmed by telephone follow ups. Also, all three patients did not report any serious side effects. The repeated magnetic resonance imaging scans at three months showed improvement of the damaged tissues (softened cartilages) on the patellae-femoral joints. In patients with chondromalacia patellae who have continuous anterior knee pain, percutaneous injection of autologous ADSCs may play an important role in the restoration of the damaged tissues (softened cartilages). Thus, ADSCs treatment presents a glimpse of a new promising, effective, safe, and non-surgical method of treatment for chondromalacia patellae. PMID:23700485

A novel biological approach to treat chondromalacia patellae.

PubMed

Pak, Jaewoo; Lee, Jung Hun; Lee, Sang Hee

2013-01-01

Mesenchymal stem cells from several sources (bone marrow, synovial tissue, cord blood, and adipose tissue) can differentiate into variable parts (bones, cartilage, muscle, and adipose tissue), representing a promising new therapy in regenerative medicine. In animal models, mesenchymal stem cells have been used successfully to regenerate cartilage and bones. However, there have been no follow-up studies on humans treated with adipose-tissue-derived stem cells (ADSCs) for the chondromalacia patellae. To obtain ADSCs, lipoaspirates were obtained from lower abdominal subcutaneous adipose tissue. The stromal vascular fraction was separated from the lipoaspirates by centrifugation after treatment with collagenase. The stem-cell-containing stromal vascular fraction was mixed with calcium chloride-activated platelet rich plasma and hyaluronic acid, and this ADSCs mixture was then injected under ultrasonic guidance into the retro-patellar joints of all three patients. Patients were subjected to pre- and post-treatment magnetic resonance imaging (MRI) scans. Pre- and post-treatment subjective pain scores and physical therapy assessments measured clinical changes. One month after the injection of autologous ADSCs, each patient's pain improved 50-70%. Three months after the treatment, the patients' pain improved 80-90%. The pain improvement persisted over 1 year, confirmed by telephone follow ups. Also, all three patients did not report any serious side effects. The repeated magnetic resonance imaging scans at three months showed improvement of the damaged tissues (softened cartilages) on the patellae-femoral joints. In patients with chondromalacia patellae who have continuous anterior knee pain, percutaneous injection of autologous ADSCs may play an important role in the restoration of the damaged tissues (softened cartilages). Thus, ADSCs treatment presents a glimpse of a new promising, effective, safe, and non-surgical method of treatment for chondromalacia patellae.

Metabolomics and transcriptomics identify pathway differences between visceral and subcutaneous adipose tissue in colorectal cancer patients: the ColoCare study12

PubMed Central

Liesenfeld, David B; Grapov, Dmitry; Fahrmann, Johannes F; Salou, Mariam; Scherer, Dominique; Toth, Reka; Habermann, Nina; Böhm, Jürgen; Schrotz-King, Petra; Gigic, Biljana; Schneider, Martin; Ulrich, Alexis; Herpel, Esther; Schirmacher, Peter; Fiehn, Oliver; Lampe, Johanna W; Ulrich, Cornelia M

2015-01-01

Background: Metabolic and transcriptomic differences between visceral adipose tissue (VAT) and subcutaneous adipose tissue (SAT) compartments, particularly in the context of obesity, may play a role in colorectal carcinogenesis. We investigated the differential functions of their metabolic compositions. Objectives: Biochemical differences between adipose tissues (VAT compared with SAT) in patients with colorectal carcinoma (CRC) were investigated by using mass spectrometry metabolomics and gene expression profiling. Metabolite compositions were compared between VAT, SAT, and serum metabolites. The relation between patients’ tumor stage and metabolic profiles was assessed. Design: Presurgery blood and paired VAT and SAT samples during tumor surgery were obtained from 59 CRC patients (tumor stages I–IV) of the ColoCare cohort. Gas chromatography time-of-flight mass spectrometry and liquid chromatography quadrupole time-of-flight mass spectrometry were used to measure 1065 metabolites in adipose tissue (333 identified compounds) and 1810 metabolites in serum (467 identified compounds). Adipose tissue gene expression was measured by using Illumina’s HumanHT-12 Expression BeadChips. Results: Compared with SAT, VAT displayed elevated markers of inflammatory lipid metabolism, free arachidonic acid, phospholipases (PLA2G10), and prostaglandin synthesis–related enzymes (PTGD/PTGS2S). Plasmalogen concentrations were lower in VAT than in SAT, which was supported by lower gene expression of FAR1, the rate-limiting enzyme for ether-lipid synthesis in VAT. Serum sphingomyelin concentrations were inversely correlated (P = 0.0001) with SAT adipose triglycerides. Logistic regression identified lipids in patients’ adipose tissues, which were associated with CRC tumor stage. Conclusions: As one of the first studies, we comprehensively assessed differences in metabolic, lipidomic, and transcriptomic profiles between paired human VAT and SAT and their association with CRC tumor stage. We identified markers of inflammation in VAT, which supports prior evidence regarding the role of visceral adiposity and cancer. This trial was registered at clinicaltrials.gov as NCT02328677. PMID:26156741

The sexual dimorphism of obesity

PubMed Central

Palmer, Biff F.; Clegg, Deborah J.

2015-01-01

The NIH has recently highlighted the importance of sexual dimorphisms and has mandated inclusion of both sexes in clinical trials and basic research. In this review we highlight new and novel ways sex hormones influence body adiposity and the metabolic syndrome. Understanding how and why metabolic processes differ by sex will enable clinicians to target and personalize therapies based on gender. Adipose tissue function and deposition differ by sex. Females differ with respect to distribution of adipose tissues, males tend to accrue more visceral fat, leading to the classic android body shape which has been highly correlated to increased cardiovascular risk; whereas females accrue more fat in the subcutaneous depot prior to menopause, a feature which affords protection from the negative consequences associated with obesity and the metabolic syndrome. After menopause, fat deposition and accrual shift to favor the visceral depot. This shift is accompanied by a parallel increase in metabolic risk reminiscent to that seen in men. A full understanding of the physiology behind why, and by what mechanisms, adipose tissues accumulate in specific depots and how these depots differ metabolically by sex is important in efforts of prevention of obesity and chronic disease. Estrogens, directly or through activation of their receptors on adipocytes and in adipose tissues, facilitate adipose tissue deposition and function. Evidence suggests that estrogens augment the sympathetic tone differentially to the adipose tissue depots favoring lipid accumulation in the subcutaneous depot in women and visceral fat deposition in men. At the level of adipocyte function, estrogens and their receptors influence the expandability of fat cells enhancing the expandability in the subcutaneous depot and inhibiting it in the visceral depot. Sex hormones clearly influence adipose tissue function and deposition, determining how to capture and utilize their function in a time of caloric surfeit, requires more information. The key will be harnessing the beneficial effects of sex hormones in such a way as to provide ‘healthy’ adiposity. PMID:25578600

Estrogen receptor protein content is different in abdominal than gluteal subcutaneous adipose tissue of overweight-to-obese premenopausal women.

PubMed

Gavin, Kathleen M; Cooper, Elizabeth E; Hickner, Robert C

2013-08-01

Premenopausal women demonstrate a distinctive gynoid body fat distribution and circulating estrogen status is associated with the maintenance of this adiposity patterning. Estrogen's role in modulation of regional adiposity may occur through estrogen receptors (ERs), which are present in human adipose tissue. The purpose of this study was to determine regional differences in the protein content of ERα, ERβ, and the G protein-coupled estrogen receptor (GPER) between the abdominal (AB) and gluteal (GL) subcutaneous adipose tissue of overweight-to-obese premenopausal women. Biopsies of the subcutaneous AB and GL adipose tissue were performed in 15 premenopausal women (7 Caucasian/8 African American, 25.1 ± 1.8 years, BMI 29.5 ± 0.5kg/m(2)). Adipose tissue protein content was measured by western blot analysis and correlation analyses were conducted to assess the relationship between ER protein content and anthropometric indices/body composition measurements. We found that ERα protein was higher in AB than GL (AB 1.0 ± 0.2 vs GL 0.67 ± 0.1 arbitrary units [AU], P=0.02), ERβ protein was higher in GL than AB (AB 0.78 ± 0.12 vs GL 1.3 ± 0.2 AU, P=0.002), ERα/ERβ ratio was higher in AB than GL (AB 1.9 ± 0.4 vs GL 0.58 ± 0.08 AU, P=0.007), and GPER protein content was similar in AB and GL (P=0.80) subcutaneous adipose tissue. Waist-to-hip ratio was inversely related to gluteal ERβ (r(2)=0.315, P=0.03) and positively related to gluteal ERα/ERβ ratio (r(2)=0.406, P=0.01). These results indicate that depot specific ER content may be an important underlying determinant of regional effects of estrogen in upper and lower body adipose tissue of overweight-to-obese premenopausal women. Copyright © 2013 Elsevier Inc. All rights reserved.

Metabolomics and transcriptomics identify pathway differences between visceral and subcutaneous adipose tissue in colorectal cancer patients: the ColoCare study.

PubMed

Liesenfeld, David B; Grapov, Dmitry; Fahrmann, Johannes F; Salou, Mariam; Scherer, Dominique; Toth, Reka; Habermann, Nina; Böhm, Jürgen; Schrotz-King, Petra; Gigic, Biljana; Schneider, Martin; Ulrich, Alexis; Herpel, Esther; Schirmacher, Peter; Fiehn, Oliver; Lampe, Johanna W; Ulrich, Cornelia M

2015-08-01

Metabolic and transcriptomic differences between visceral adipose tissue (VAT) and subcutaneous adipose tissue (SAT) compartments, particularly in the context of obesity, may play a role in colorectal carcinogenesis. We investigated the differential functions of their metabolic compositions. Biochemical differences between adipose tissues (VAT compared with SAT) in patients with colorectal carcinoma (CRC) were investigated by using mass spectrometry metabolomics and gene expression profiling. Metabolite compositions were compared between VAT, SAT, and serum metabolites. The relation between patients' tumor stage and metabolic profiles was assessed. Presurgery blood and paired VAT and SAT samples during tumor surgery were obtained from 59 CRC patients (tumor stages I-IV) of the ColoCare cohort. Gas chromatography time-of-flight mass spectrometry and liquid chromatography quadrupole time-of-flight mass spectrometry were used to measure 1065 metabolites in adipose tissue (333 identified compounds) and 1810 metabolites in serum (467 identified compounds). Adipose tissue gene expression was measured by using Illumina's HumanHT-12 Expression BeadChips. Compared with SAT, VAT displayed elevated markers of inflammatory lipid metabolism, free arachidonic acid, phospholipases (PLA2G10), and prostaglandin synthesis-related enzymes (PTGD/PTGS2S). Plasmalogen concentrations were lower in VAT than in SAT, which was supported by lower gene expression of FAR1, the rate-limiting enzyme for ether-lipid synthesis in VAT. Serum sphingomyelin concentrations were inversely correlated (P = 0.0001) with SAT adipose triglycerides. Logistic regression identified lipids in patients' adipose tissues, which were associated with CRC tumor stage. As one of the first studies, we comprehensively assessed differences in metabolic, lipidomic, and transcriptomic profiles between paired human VAT and SAT and their association with CRC tumor stage. We identified markers of inflammation in VAT, which supports prior evidence regarding the role of visceral adiposity and cancer. © 2015 American Society for Nutrition.

A Stratified Transcriptomics Analysis of Polygenic Fat and Lean Mouse Adipose Tissues Identifies Novel Candidate Obesity Genes

PubMed Central

Morton, Nicholas M.; Nelson, Yvonne B.; Michailidou, Zoi; Di Rollo, Emma M.; Ramage, Lynne; Hadoke, Patrick W. F.; Seckl, Jonathan R.; Bunger, Lutz; Horvat, Simon; Kenyon, Christopher J.; Dunbar, Donald R.

2011-01-01

Background Obesity and metabolic syndrome results from a complex interaction between genetic and environmental factors. In addition to brain-regulated processes, recent genome wide association studies have indicated that genes highly expressed in adipose tissue affect the distribution and function of fat and thus contribute to obesity. Using a stratified transcriptome gene enrichment approach we attempted to identify adipose tissue-specific obesity genes in the unique polygenic Fat (F) mouse strain generated by selective breeding over 60 generations for divergent adiposity from a comparator Lean (L) strain. Results To enrich for adipose tissue obesity genes a ‘snap-shot’ pooled-sample transcriptome comparison of key fat depots and non adipose tissues (muscle, liver, kidney) was performed. Known obesity quantitative trait loci (QTL) information for the model allowed us to further filter genes for increased likelihood of being causal or secondary for obesity. This successfully identified several genes previously linked to obesity (C1qr1, and Np3r) as positional QTL candidate genes elevated specifically in F line adipose tissue. A number of novel obesity candidate genes were also identified (Thbs1, Ppp1r3d, Tmepai, Trp53inp2, Ttc7b, Tuba1a, Fgf13, Fmr) that have inferred roles in fat cell function. Quantitative microarray analysis was then applied to the most phenotypically divergent adipose depot after exaggerating F and L strain differences with chronic high fat feeding which revealed a distinct gene expression profile of line, fat depot and diet-responsive inflammatory, angiogenic and metabolic pathways. Selected candidate genes Npr3 and Thbs1, as well as Gys2, a non-QTL gene that otherwise passed our enrichment criteria were characterised, revealing novel functional effects consistent with a contribution to obesity. Conclusions A focussed candidate gene enrichment strategy in the unique F and L model has identified novel adipose tissue-enriched genes contributing to obesity. PMID:21915269

A stratified transcriptomics analysis of polygenic fat and lean mouse adipose tissues identifies novel candidate obesity genes.

PubMed

Morton, Nicholas M; Nelson, Yvonne B; Michailidou, Zoi; Di Rollo, Emma M; Ramage, Lynne; Hadoke, Patrick W F; Seckl, Jonathan R; Bunger, Lutz; Horvat, Simon; Kenyon, Christopher J; Dunbar, Donald R

2011-01-01

Obesity and metabolic syndrome results from a complex interaction between genetic and environmental factors. In addition to brain-regulated processes, recent genome wide association studies have indicated that genes highly expressed in adipose tissue affect the distribution and function of fat and thus contribute to obesity. Using a stratified transcriptome gene enrichment approach we attempted to identify adipose tissue-specific obesity genes in the unique polygenic Fat (F) mouse strain generated by selective breeding over 60 generations for divergent adiposity from a comparator Lean (L) strain. To enrich for adipose tissue obesity genes a 'snap-shot' pooled-sample transcriptome comparison of key fat depots and non adipose tissues (muscle, liver, kidney) was performed. Known obesity quantitative trait loci (QTL) information for the model allowed us to further filter genes for increased likelihood of being causal or secondary for obesity. This successfully identified several genes previously linked to obesity (C1qr1, and Np3r) as positional QTL candidate genes elevated specifically in F line adipose tissue. A number of novel obesity candidate genes were also identified (Thbs1, Ppp1r3d, Tmepai, Trp53inp2, Ttc7b, Tuba1a, Fgf13, Fmr) that have inferred roles in fat cell function. Quantitative microarray analysis was then applied to the most phenotypically divergent adipose depot after exaggerating F and L strain differences with chronic high fat feeding which revealed a distinct gene expression profile of line, fat depot and diet-responsive inflammatory, angiogenic and metabolic pathways. Selected candidate genes Npr3 and Thbs1, as well as Gys2, a non-QTL gene that otherwise passed our enrichment criteria were characterised, revealing novel functional effects consistent with a contribution to obesity. A focussed candidate gene enrichment strategy in the unique F and L model has identified novel adipose tissue-enriched genes contributing to obesity.

Targeting obesity-related adipose tissue dysfunction to prevent cancer development and progression

PubMed Central

Gucalp, Ayca; Iyengar, Neil M.; Hudis, Clifford A.; Dannenberg, Andrew J.

2016-01-01

The incidence of obesity, a leading modifiable risk factor for common solid tumors, is increasing. Effective interventions are needed to minimize the public health implications of obesity. Although the mechanisms linking increased adiposity to malignancy are incompletely understood, growing evidence points to complex interactions among multiple systemic and tissue-specific pathways including inflamed white adipose tissue. The metabolic and inflammatory consequences of white adipose tissue dysfunction collectively provide a plausible explanation for the link between overweight/obesity and carcinogenesis. Gaining a better understanding of these underlying molecular pathways and developing risk assessment tools that identify at-risk populations will be critical in implementing effective and novel cancer prevention and management strategies. PMID:26970134

A worm of one's own: how helminths modulate host adipose tissue function and metabolism.

PubMed

Guigas, Bruno; Molofsky, Ari B

2015-09-01

Parasitic helminths have coexisted with human beings throughout time. Success in eradicating helminths has limited helminth-induced morbidity and mortality but is also correlated with increasing rates of 'western' diseases, including metabolic syndrome and type 2 diabetes. Recent studies in mice describe how type 2 immune cells, traditionally associated with helminth infection, maintain adipose tissue homeostasis and promote adipose tissue beiging, protecting against obesity and metabolic dysfunction. Here, we review these studies and discuss how helminths and helminth-derived molecules may modulate these physiologic pathways to improve metabolic functions in specific tissues, such as adipose and liver, as well as at the whole-organism level. Copyright © 2015 Elsevier Ltd. All rights reserved.

A worm of one’s own: how helminths modulate host adipose tissue function and metabolism

PubMed Central

Guigas, Bruno; Molofsky, Ari B.

2015-01-01

Parasitic helminths have co-existed with human beings throughout time. Success in eradicating helminths has limited helminth-induced morbidity and mortality but is also correlated with increasing rates of ‘Western’ diseases, including metabolic syndrome and type 2 diabetes. Recent studies in mice describe how type 2 immune cells, traditionally associated with helminth infection, maintain adipose tissue homeostasis and promote adipose tissue beiging, protecting against obesity and metabolic dysfunction. Here we review these studies and discuss how helminths and helminth-derived molecules may modulate these physiologic pathways to improve metabolic functions in specific tissues, such as adipose and liver, as well as at the whole-organism level. PMID:25991556

Association of lifestyle factors with abdominal subcutaneous and visceral adiposity: The Framingham Heart Study

USDA-ARS?s Scientific Manuscript database

The objective of the present study was to assess the relationship between lifestyle factors and abdominal subcutaneous adipose tissue (SAT) and visceral adipose tissue (VAT) in a community-based setting. Cross-sectional associations between lifestyle factors (dietary quality, physical activity, smo...

Fatty Acid Composition of Muscle, Adipose Tissue and Liver from Muskoxen (Ovibos moschatus) Living in West Greenland

PubMed Central

Alves, Susana P.; Raundrup, Katrine; Cabo, Ângelo; Bessa, Rui J. B.; Almeida, André M.

2015-01-01

Information about lipid content and fatty acid (FA) composition of muskoxen (Ovibos moschatos) edible tissues is very limited in comparison to other meat sources. Thus, this work aims to present the first in-depth characterization of the FA profile of meat, subcutaneous adipose tissue and liver of muskoxen living in West Greenland. Furthermore, we aim to evaluate the effect of sex in the FA composition of these edible tissues. Samples from muscle (Longissimus dorsi), subcutaneous adipose tissue and liver were collected from female and male muskoxen, which were delivered at the butchery in Kangerlussuaq (West Greenland) during the winter hunting season. The lipid content of muscle, adipose tissue and liver averaged 284, 846 and 173 mg/g of dry tissue, respectively. This large lipid contents confirms that in late winter, when forage availability is scarce, muskoxen from West Greenland still have high fat reserves, demonstrating that they are well adapted to seasonal feed restriction. A detailed characterization of FA and dimethylacetal composition of muskoxen muscle, subcutaneous adipose tissue and liver showed that there are little differences on FA composition between sexes. Nevertheless, the 18:1cis-9 was the most abundant FA in muscle and adipose tissue, reaching 43% of total FA in muscle. The high content of 18:1cis-9 suggests that it can be selectively stored in muskoxen tissues. Regarding the nutritional composition of muskoxen edible tissues, they are not a good source of polyunsaturated FA; however, they may contribute to a higher fat intake. Information about the FA composition of muskoxen meat and liver is scarce, so this work can contribute to the characterization of the nutritional fat properties of muskoxen edible tissues and can be also useful to update food composition databases. PMID:26678792

Trypanosoma brucei parasites occupy and functionally adapt to the adipose tissue in mice

DOE Office of Scientific and Technical Information (OSTI.GOV)

Trindade, Sandra; Rijo-Ferreira, Filipa; Carvalho, Tania

Trypanosoma brucei is an extracellular parasite that causes sleeping sickness. In mammalian hosts, trypanosomes are thought to exist in two major niches: early in infection, they populate the blood; later, they breach the blood-brain barrier. Working with a well-established mouse model, we discovered that adipose tissue constitutes a third major reservoir for T. brucei. Parasites from adipose tissue, here termed adipose tissue forms (ATFs), can replicate and were capable of infecting a naive animal. ATFs were transcriptionally distinct from bloodstream forms, and the genes upregulated included putative fatty acid β-oxidation enzymes. Consistent with this, ATFs were able to utilize exogenousmore » myristate and form β-oxidation intermediates, suggesting that ATF parasites can use fatty acids as an external carbon source. Lastly, these findings identify the adipose tissue as a niche for T. brucei during its mammalian life cycle and could potentially explain the weight loss associated with sleeping sickness.« less

PGRN is a key adipokine mediating high fat diet-induced insulin resistance and obesity through IL-6 in adipose tissue.

PubMed

Matsubara, Toshiya; Mita, Ayako; Minami, Kohtaro; Hosooka, Tetsuya; Kitazawa, Sohei; Takahashi, Kenichi; Tamori, Yoshikazu; Yokoi, Norihide; Watanabe, Makoto; Matsuo, Ei-Ichi; Nishimura, Osamu; Seino, Susumu

2012-01-04

Adipose tissue secretes adipokines that mediate insulin resistance, a characteristic feature of obesity and type 2 diabetes. By differential proteome analysis of cellular models of insulin resistance, we identified progranulin (PGRN) as an adipokine induced by TNF-α and dexamethasone. PGRN in blood and adipose tissues was markedly increased in obese mouse models and was normalized with treatment of pioglitazone, an insulin-sensitizing agent. Ablation of PGRN (Grn(-/-)) prevented mice from high fat diet (HFD)-induced insulin resistance, adipocyte hypertrophy, and obesity. Grn deficiency blocked elevation of IL-6, an inflammatory cytokine, induced by HFD in blood and adipose tissues. Insulin resistance induced by chronic administration of PGRN was suppressed by neutralizing IL-6 in vivo. Thus, PGRN is a key adipokine that mediates HFD-induced insulin resistance and obesity through production of IL-6 in adipose tissue, and may be a promising therapeutic target for obesity. Copyright © 2012 Elsevier Inc. All rights reserved.

A macrophage NBR1-MEKK3 complex triggers JNK-mediated adipose-tissue inflammation in obesity

PubMed Central

Hernandez, Eloy D.; Lee, Sang Jun; Kim, Ji Young; Duran, Angeles; Linares, Juan F.; Yajima, Tomoko; Müller, Timo D.; Tschöp, Matthias H.; Smith, Steven R.; Diaz-Meco, Maria T.; Moscat, Jorge

2014-01-01

SUMMARY The c-Jun NH(2)-terminal kinase (JNK) is a critical determinant of obesity-associated inflammation and glucose intolerance. The upstream mechanisms controlling this pathway are still unknown. Here we report that the levels of the PB1 domain-containing adapter NBR1 correlated with the expression of pro-inflammatory molecules in adipose tissue from human patients with metabolic syndrome, suggesting that NBR1 plays a key role in adipose-tissue inflammation. We also show that NBR1 inactivation in the myeloid compartment impairs the function, M1 polarization and chemotactic activity of macrophages, prevents inflammation of adipose tissue, and improves glucose tolerance in obese mice. Furthermore, we demonstrate that an interaction between the PB1 domains of NBR1 and the mitogen-activated kinase kinase 3 (MEKK3) enables the formation of a signaling complex required for the activation of JNK. Together these discoveries identify an NBR1-MEKK3 complex as a key regulator of JNK signaling and adipose-tissue inflammation in obesity. PMID:25043814

Trypanosoma brucei parasites occupy and functionally adapt to the adipose tissue in mice

DOE PAGES

Trindade, Sandra; Rijo-Ferreira, Filipa; Carvalho, Tania; ...

2016-05-26

Trypanosoma brucei is an extracellular parasite that causes sleeping sickness. In mammalian hosts, trypanosomes are thought to exist in two major niches: early in infection, they populate the blood; later, they breach the blood-brain barrier. Working with a well-established mouse model, we discovered that adipose tissue constitutes a third major reservoir for T. brucei. Parasites from adipose tissue, here termed adipose tissue forms (ATFs), can replicate and were capable of infecting a naive animal. ATFs were transcriptionally distinct from bloodstream forms, and the genes upregulated included putative fatty acid β-oxidation enzymes. Consistent with this, ATFs were able to utilize exogenousmore » myristate and form β-oxidation intermediates, suggesting that ATF parasites can use fatty acids as an external carbon source. Lastly, these findings identify the adipose tissue as a niche for T. brucei during its mammalian life cycle and could potentially explain the weight loss associated with sleeping sickness.« less

Adenovirus 36 DNA in human adipose tissue.

PubMed

Ponterio, E; Cangemi, R; Mariani, S; Casella, G; De Cesare, A; Trovato, F M; Garozzo, A; Gnessi, L

2015-12-01

Recent studies have suggested a possible correlation between obesity and adenovirus 36 (Adv36) infection in humans. As information on adenoviral DNA presence in human adipose tissue are limited, we evaluated the presence of Adv36 DNA in adipose tissue of 21 adult overweight or obese patients. Total DNA was extracted from adipose tissue biopsies. Virus detection was performed using PCR protocols with primers against specific Adv36 fiber protein and the viral oncogenic E4orf1 protein nucleotide sequences. Sequences were aligned with the NCBI database and phylogenetic analyses were carried out with MEGA6 software. Adv36 DNA was found in four samples (19%). This study indicates that some individuals carry Adv36 in the visceral adipose tissue. Further studies are needed to determine the specific effect of Adv36 infection on adipocytes, the prevalence of Adv36 infection and its relationship with obesity in the perspective of developing a vaccine that could potentially prevent or mitigate infection.

Docosahexaenoic acid (DHA) at the sn-2 position of triacylglycerols increases DHA incorporation in brown, but not in white adipose tissue, of hamsters.

PubMed

Lopes, Paula A; Bandarra, Narcisa M; Martins, Susana V; Madeira, Marta S; Ferreira, Júlia; Guil-Guerrero, José L; Prates, José A M

2018-06-01

We hypothesised that the incorporation of docosahexaenoic acid (DHA) across adipose tissues will be higher when it is ingested as triacylglycerols (TAG) structured at the sn-2 position. Ten-week old male hamsters were allocated to 4 dietary treatments (n = 10): linseed oil (LSO-control group), fish oil (FO), fish oil ethyl esters (FO-EE) and structured DHA at the sn-2 position of TAG (DHA-SL) during 12 weeks. In opposition to the large variations found for fatty acid composition in retroperitoneal white adipose tissue (WAT), brown adipose tissue (BAT) was less responsive to diets. DHA was not found in subcutaneous and retroperitoneal WAT depots but it was successfully incorporated in BAT reaching the highest percentage in DHA-SL. The PCA on plasma hormones (insulin, leptin, adiponectin) and fatty acids discriminated BAT from WATs pointing towards an individual signature on fatty acid deposition, but did not allow for full discrimination of dietary treatments within each adipose tissue.

[Effects of the escharectomy during burn shock stage on expression of glucose translator-4 mRNA in skeletal muscle and adipose tissue].

PubMed

Shuai, Xiu-rong; Liu, Tong-fa; Guo, Zhen-rong; Yu, Shun-xian; He, Peng-fei; Yuan, Wen-zhou; Li, Feng; He, Li-xin

2004-04-07

To investigate the effect of the escharectomy during burn shock stage on expression of glucose translator-4 (GLUT4) mRNA in skeletal muscle and adipose tissue. 30% TBSA scalded rats were employed. Escharectomy were conducted at 8 h, 24 h, 168 h after burns respectively. Insulin, glucagon, cortisol and glucose levels in serum were analyzed. RT-PCR were employed to analyze GLUT4 mRNA expression in skeletal muscle and adipose tissue. Glucagon, cortisol and glucose levels in serum were declined in groups which escharectomy were conducted during burn shock stage. GLUT4 mRNA expression in both skeletal muscle and adipose tissue were downregulated after burns and escharectomy conducted during burn shock stage made it restored to near normal. GLUT4 mRNA expression will declined after major burns in skeletal muscle and adipose tissue. Escharectomy during shock stage could make it upregulated, which will be helpful to improve glucose metabolism and hypermetabolism after major burns.

Regulation of metabolic health and adipose tissue function by group 2 innate lymphoid cells

PubMed Central

Cautivo, Kelly M.; Molofsky, Ari B.

2016-01-01

Adipose tissue (AT) is home to an abundance of immune cells. With chronic obesity, inflammatory immune cells accumulate and promote insulin resistance and the progression to type 2 diabetes mellitus (T2DM). In contrast, recent studies have highlighted the regulation and function of immune cells in lean, healthy adipose tissue, including those associated with type 2 or “allergic” immunity. Although traditionally activated by infection with multicellular helminthes, AT type 2 immunity is active independently of infection, and promotes tissue homeostasis, adipose tissue “browning”, and systemic insulin sensitivity, protecting against obesity-induced metabolic dysfunction and T2DM. In particular, group 2 innate lymphoid cells (ILC2s) are integral regulators of AT type 2 immunity, producing the cytokines IL-5 and IL-13, promoting eosinophils and alternatively activated macrophages, and cooperating with and promoting AT regulatory T (Treg) cells. In this review, we focus on the recent developments in our understanding of ILC2 cells and type 2 immunity in adipose tissue metabolism and homeostasis. PMID:27120716

Effect of Topically Applied Diisopropylfluorophosphate on Glucose Metabolism in the Rat.

DTIC Science & Technology

1982-12-01

intermediary metabolism, * liver , adipose tissue topical application. DFP - diisopropylfluorophosphate OL AIISTRACT’MOMNomrse sft NOMNY Ol~ dulp lekib) .1A...skin, liver and adipose tissue preparations were determined. DFP had no demonstratable effect on glucose oxidation. In contrast, DFP enhanced fatty...acid synthesis by 70% over the control values in the skin and by 56 and 92% in the liver and adipose tissue, respectively. DFP stimulated synthesis. of

Exercise and caloric restriction alter the immune system of mice submitted to a high-fat diet.

PubMed

Wasinski, Frederick; Bacurau, Reury F P; Moraes, Milton R; Haro, Anderson S; Moraes-Vieira, Pedro M M; Estrela, Gabriel R; Paredes-Gamero, Edgar J; Barros, Carlos C; Almeida, Sandro S; Câmara, Niels O S; Araujo, Ronaldo C

2013-01-01

As the size of adipocytes increases during obesity, the establishment of resident immune cells in adipose tissue becomes an important source of proinflammatory mediators. Exercise and caloric restriction are two important, nonpharmacological tools against body mass increase. To date, their effects on the immune cells of adipose tissue in obese organisms, specifically when a high-fat diet is consumed, have been poorly investigated. Thus, after consuming a high-fat diet, mice were submitted to chronic swimming training or a 30% caloric restriction in order to investigate the effects of both interventions on resident immune cells in adipose tissue. These strategies were able to reduce body mass and resulted in changes in the number of resident immune cells in the adipose tissue and levels of cytokines/chemokines in serum. While exercise increased the number of NK cells in adipose tissue and serum levels of IL-6 and RANTES, caloric restriction increased the CD4+/CD8+ cell ratio and MCP-1 levels. Together, these data demonstrated that exercise and caloric restriction modulate resident immune cells in adipose tissues differently in spite of an equivalent body weight reduction. Additionally, the results also reinforce the idea that a combination of both strategies is better than either individually for combating obesity.

Dietary ribonucleic acid suppresses inflammation of adipose tissue and improves glucose intolerance that is mediated by immune cells in C57BL/6 mice fed a high-fat diet.

PubMed

Sakai, Tohru; Taki, Tomoyo; Nakamoto, Akiko; Tazaki, Shiho; Arakawa, Mai; Nakamoto, Mariko; Tsutsumi, Rie; Shuto, Emi

2015-01-01

Recent evidence suggests that immune cells play an important role in differentiation of inflammatory macrophages in adipose tissue, which contributes to systemic chronic inflammation. Dietary ribonucleic acid (RNA) has been shown to modulate immune function. We hypothesized that RNA affects immune cell function in adipose tissue and then improves inflammatory response in adipose tissue. C57/BL6 mice and recombination activating gene-1 (RAG-1) knockout mice on a C57BL/6 mice background were fed a high-fat diet containing 1% RNA for 12 wk. An oral glucose tolerance test was performed. Supplementation of dietary RNA in C57BL/6 mice fed a high-fat diet resulted in a smaller area under the curve (AUC) after oral glucose administration than that for control mice. The mRNA expression levels of inflammation-related cytokines in adipose tissue and serum interleukin-6 levels were reduced by dietary RNA supplementation. Interestingly, reduction of the AUC value by RNA supplementation was abolished in T and B cell-deficient RAG-1 knockout mice. These results indicate that RNA improves inflammation in adipose tissue and reduces the AUC value following oral glucose administration in a T and B cell-dependent manner.

Chemical chaperones reduce ER stress and adipose tissue inflammation in high fat diet-induced mouse model of obesity.

PubMed

Chen, Yaqin; Wu, Zhihong; Zhao, Shuiping; Xiang, Rong

2016-06-08

Obesity, which is characteristic by chronic inflammation, is defined as abnormal or excessive fat accumulation in adipose tissues. Endoplasmic reticulum (ER) stress is increased in adipose tissue of obese state and is known to be strongly associated with chronic inflammation. The aim of this study was to investigate the effect of ER stress on adipokine secretion in obese mice and explore the potential mechanisms. In this study, we found high-fat diet induced-obesity contributed to strengthened ER stress and triggered chronic inflammation in adipose tissue. Chemical chaperones, 4-PBA and TUDCA, modified metabolic disorders and decreased the levels of inflammatory cytokines in obese mice fed a high-fat diet. The alleviation of ER stress is in accordance with the decrease of free cholesterol in adipose tissue. Furthermore chemical chaperones suppress NF-κB activity in adipose tissue of obese mice in vivo. In vitro studies showed IKK/NF-κB may be involved in the signal transduction of adipokine secretion dysfunction induced by ER stress. The present study revealed the possibility that inhibition of ER stress may be a novel drug target for metabolic abnormalities associated with obesity. Further studies are now needed to characterize the initial incentive of sustained ER stress in obese.

Allele compensation in tip60+/- mice rescues white adipose tissue function in vivo.

PubMed

Gao, Yuan; Hamers, Nicole; Rakhshandehroo, Maryam; Berger, Ruud; Lough, John; Kalkhoven, Eric

2014-01-01

Adipose tissue is a key regulator of energy homestasis. The amount of adipose tissue is largely determined by adipocyte differentiation (adipogenesis), a process that is regulated by the concerted actions of multiple transcription factors and cofactors. Based on in vitro studies in murine 3T3-L1 preadipocytes and human primary preadipocytes, the transcriptional cofactor and acetyltransferase Tip60 was recently identified as an essential adipogenic factor. We therefore investigated the role of Tip60 on adipocyte differentiation and function, and possible consequences on energy homeostasis, in vivo. Because homozygous inactivation results in early embryonic lethality, Tip60+/- mice were used. Heterozygous inactivation of Tip60 had no effect on body weight, despite slightly higher food intake by Tip60+/- mice. No major effects of heterozygous inactivation of Tip60 were observed on adipose tissue and liver, and Tip60+/- displayed normal glucose tolerance, both on a low fat and a high fat diet. While Tip60 mRNA was reduced to 50% in adipose tissue, the protein levels were unaltered, suggesting compensation by the intact allele. These findings indicate that the in vivo role of Tip60 in adipocyte differentiation and function cannot be properly addressed in Tip60+/- mice, but requires the generation of adipose tissue-specific knock out animals or specific knock-in mice.

Inhibition of intestinal cholesterol absorption decreases atherosclerosis but not adipose tissue inflammation

PubMed Central

Umemoto, Tomio; Subramanian, Savitha; Ding, Yilei; Goodspeed, Leela; Wang, Shari; Han, Chang Yeop; Teresa, Antonio Sta.; Kim, Jinkyu; O'Brien, Kevin D.; Chait, Alan

2012-01-01

Adipose tissue inflammation is associated with insulin resistance and increased cardiovascular disease risk in obesity. We previously showed that addition of cholesterol to a diet rich in saturated fat and refined carbohydrate significantly worsens dyslipidemia, insulin resistance, adipose tissue macrophage accumulation, systemic inflammation, and atherosclerosis in LDL receptor-deficient (Ldlr−/−) mice. To test whether inhibition of intestinal cholesterol absorption would improve metabolic abnormalities and adipose tissue inflammation in obesity, we administered ezetimibe, a dietary and endogenous cholesterol absorption inhibitor, to Ldlr−/− mice fed chow or high-fat, high-sucrose (HFHS) diets without or with 0.15% cholesterol (HFHS+C). Ezetimibe blunted weight gain and markedly reduced plasma lipids in the HFHS+C group. Ezetimibe had no effect on glucose homeostasis or visceral adipose tissue macrophage gene expression in the HFHS+C fed mice, although circulating inflammatory markers serum amyloid A (SSA) and serum amyloid P (SSP) levels decreased. Nevertheless, ezetimibe treatment led to a striking (>85%) reduction in atherosclerotic lesion area with reduced lesion lipid and macrophage content in the HFHS+C group. Thus, in the presence of dietary cholesterol, ezetimibe did not improve adipose tissue inflammation in obese Ldlr−/− mice, but it led to a major reduction in atherosclerotic lesions associated with improved plasma lipids and lipoproteins. PMID:22956784

Sex-specific metabolic interactions between liver and adipose tissue in MCD diet-induced non-alcoholic fatty liver disease.

PubMed

Lee, Yun-Hee; Kim, Sou Hyun; Kim, Sang-Nam; Kwon, Hyun-Jung; Kim, Jeong-Dong; Oh, Ji Youn; Jung, Young-Suk

2016-07-26

Higher susceptibility to metabolic disease in male exemplifies the importance of sexual dimorphism in pathogenesis. We hypothesized that the higher incidence of non-alcoholic fatty liver disease in males involves sex-specific metabolic interactions between liver and adipose tissue. In the present study, we used a methionine-choline deficient (MCD) diet-induced fatty liver mouse model to investigate sex differences in the metabolic response of the liver and adipose tissue. After 2 weeks on an MCD-diet, fatty liver was induced in a sex-specific manner, affecting male mice more severely than females. The MCD-diet increased lipolytic enzymes in the gonadal white adipose tissue (gWAT) of male mice, whereas it increased expression of uncoupling protein 1 and other brown adipocyte markers in the gWAT of female mice. Moreover, gWAT from female mice demonstrated higher levels of oxygen consumption and mitochondrial content compared to gWAT from male mice. FGF21 expression was increased in liver tissue by the MCD diet, and the degree of upregulation was significantly higher in the livers of female mice. The endocrine effect of FGF21 was responsible, in part, for the sex-specific browning of gonadal white adipose tissue. Collectively, these data demonstrated that distinctively female-specific browning of white adipose tissue aids in protecting female mice against MCD diet-induced fatty liver disease.

Sex-specific metabolic interactions between liver and adipose tissue in MCD diet-induced non-alcoholic fatty liver disease

PubMed Central

Lee, Yun-Hee; Kim, Sou Hyun; Kim, Sang-Nam; Kwon, Hyun-Jung; Kim, Jeong-Dong; Oh, Ji Youn; Jung, Young-Suk

2016-01-01

Higher susceptibility to metabolic disease in male exemplifies the importance of sexual dimorphism in pathogenesis. We hypothesized that the higher incidence of non-alcoholic fatty liver disease in males involves sex-specific metabolic interactions between liver and adipose tissue. In the present study, we used a methionine-choline deficient (MCD) diet-induced fatty liver mouse model to investigate sex differences in the metabolic response of the liver and adipose tissue. After 2 weeks on an MCD-diet, fatty liver was induced in a sex-specific manner, affecting male mice more severely than females. The MCD-diet increased lipolytic enzymes in the gonadal white adipose tissue (gWAT) of male mice, whereas it increased expression of uncoupling protein 1 and other brown adipocyte markers in the gWAT of female mice. Moreover, gWAT from female mice demonstrated higher levels of oxygen consumption and mitochondrial content compared to gWAT from male mice. FGF21 expression was increased in liver tissue by the MCD diet, and the degree of upregulation was significantly higher in the livers of female mice. The endocrine effect of FGF21 was responsible, in part, for the sex-specific browning of gonadal white adipose tissue. Collectively, these data demonstrated that distinctively female-specific browning of white adipose tissue aids in protecting female mice against MCD diet-induced fatty liver disease. PMID:27409675

Cold-Induced Browning Dynamically Alters the Expression Profiles of Inflammatory Adipokines with Tissue Specificity in Mice.

PubMed

Luo, Xiao; Jia, Ru; Zhang, Qiangling; Sun, Bo; Yan, Jianqun

2016-05-23

Cold exposure or β₃-adrenoceptor agonist treatment induces the adipose tissues remodeling, relevant for beige adipogenesis within white adipose tissue (WAT). It remains unclear whether this process influences inflammatory adipokines expression in adipose tissues. We determine the temporal profile of cold or β₃-adrenoceptor agonist (CL316,243)-induced changes in the expression of inflammatory adipokines in adipose tissues in mice or primary mice adipocytes. Male C57BL/6J mice at eight weeks old were exposed to 4 °C for 1-5 days. Interscapular brown adipose tissue (iBAT), inguinal subcutaneous WAT (sWAT) and epididymal WAT (eWAT) were harvested for gene and protein expression analysis. In addition, cultured primary mice brown adipocyte (BA) and white adipocyte (WA) treated with or without CL316,243 were harvested for gene expression analysis. The inflammatory adipokines expressed significantly higher in WAT than BAT at baseline. They were rapidly changed in iBAT, while down-regulated in sWAT and up-regulated in eWAT during the cold acclimation. Upon CL316,243 treatment, detected inflammatory adipokines except Leptin were transiently increased in both BA and WA. Our in vivo and in vitro data demonstrate that the browning process alters the inflammatory adipokines expression in adipose tissues, which is acutely responded to in iBAT, dynamically decreased in sWAT whilst increased in eWAT for compensation.

Leptin differentially regulates STAT3 activation in the ob/ob mice adipose mesenchymal stem cells

USDA-ARS?s Scientific Manuscript database

Leptin-deficient genetically obese ob/ob mice exhibit adipocyte hypertrophy and hyperplasia as well as elevated adipose tissue and systemic inflammation. Studies have shown that multipotent stem cells isolated from adult adipose tissue can differentiate into adipocytes ex vivo and thereby contribute...

Adipose tissue redistribution caused by an early consumption of a high sucrose diet in a rat model.

PubMed

Castellanos Jankiewicz, Ashley Kate; Rodríguez Peredo, Sofía Montserrat; Cardoso Saldaña, Guillermo; Díaz Díaz, Eulises; Tejero Barrera, María Elizabeth; del Bosque Plata, Laura; Carbó Zabala, Roxana

2015-06-01

Obesity is a major public health problem worldwide. The quantity and site of accumulation of adipose tissue is of great importance for the physiopathology of this disease. The aim of this study was to assess the effect of a high carbohydrate diet on adipose tissue distribution. Male Wistar rats, control (CONT) and high sucrose diet (HSD; 30% sucrose in their drinking water), were monitored during 24 weeks and total energy and macronutrient intake were estimated by measuring daily average consumption. A bioelectrical impedance procedure was performed at 22 weeks of treatment to assess body compartments and systolic arterial blood pressure was measured. Serum was obtained and retroperitoneal adipose tissue was collected and weighed. HSD ingested less pellets and beverage, consuming less lipids and proteins than CONT, but the same amount of carbohydrates. Retroperitoneal adipose tissue was more abundant in HSD. Both groups were normoglycemic; triglycerides, adiponectin and leptin levels were higher, while total cholesterol and HDL-cholesterol were lower in HSD; insulin, HOMA index and systolic blood pressure had a tendency of being higher in HSD. This model presents dyslipidemia and a strong tendency for insulin resistance and hypertension. Even though there was no difference in body compartments between groups, retroperitoneal adipose tissue was significantly increased in HSD. This suggests that a rearrangement of adipose tissue distribution towards the abdominal cavity takes place as a result of chronic high sucrose consumption, which contributes to a higher risk of suffering from metabolic and chronic degenerative diseases. Copyright AULA MEDICA EDICIONES 2014. Published by AULA MEDICA. All rights reserved.

Botulinum toxin A improves adipose tissue engraftment by promoting cell proliferation, adipogenesis and angiogenesis

PubMed Central

Tang, Qi; Chen, Chang; Wang, Xiaqi; Li, Wei; Zhang, Yan; Wang, Muyao; Jing, Wei; Wang, Hang; Guo, Weihua; Tian, Weidong

2017-01-01

Adipose tissue engraftment has become a well-established therapy in plastic and reconstructive surgery used to restore age-related or injury-related soft tissue loss. However, the unpredictable absorption rates limit its further application. Some clinicians have noted that more optimal aesthetic results are achieved when botulinum toxin A (BoNTA) is applied prior to adipose tissue grafting. In the present study, we transplanted allogeneic adipose tissue treated with or without BoNTA in SD rats in vivo. We subsequently evaluated the survival rate (weight, volume, apoptosis and cellular integrity) and revascularization of the adipose tissue. The results revealed that BoNTA improved the long-term weight and volume retention of the graft, and preserved cellular integrity. BoNTA significantly increased the expression levels of CD31 and vascular endothelial growth factor (VEGF), suggesting enhanced vasodilation and endothelial cell proliferation. In vitro, adipose-derived stem cells (ASCs) were isolated, identified and induced to proliferate and differentiate with or without BoNTA. Furthermore, to evaluate the proliferative, adipogenic and angiogenic ability of the ASCs, CCK-8 assay and Oil Red O staining were conducted. Gene and protein expression levels were analyzed by RT-qPCR and western blot analysis. The results revealed that 8×10−2 U/ml BoNTA as the optimal dose increased ASC proliferation and adipogenic differentiation capacity, as well as the expression level of the key cytokine of angiogenesis. On the whole, our findings indicate that BoNTA improves adipose tissue engraftment and promotes ASC regeneration, which could benefit future clinical applications. PMID:28731141

Developmental programming, adiposity, and reproduction in ruminants.

PubMed

Symonds, M E; Dellschaft, N; Pope, M; Birtwistle, M; Alagal, R; Keisler, D; Budge, H

2016-07-01

Although sheep have been widely adopted as an animal model for examining the timing of nutritional interventions through pregnancy on the short- and long-term outcomes, only modest programming effects have been seen. This is due in part to the mismatch in numbers of twins and singletons between study groups as well as unequal numbers of males and females. Placental growth differs between singleton and twin pregnancies which can result in different body composition in the offspring. One tissue that is especially affected is adipose tissue which in the sheep fetus is primarily located around the kidneys and heart plus the sternal/neck region. Its main role is the rapid generation of heat due to activation of the brown adipose tissue-specific uncoupling protein 1 at birth. The fetal adipose tissue response to suboptimal maternal food intake at defined stages of development differs between the perirenal abdominal and pericardial depots, with the latter being more sensitive. Fetal adipose tissue growth may be mediated in part by changes in leptin status of the mother which are paralleled in the fetus. Then, over the first month of life plasma leptin is higher in females than males despite similar adiposity, when fat is the fastest growing tissue with the sternal/neck depot retaining uncoupling protein 1, whereas other depots do not. Future studies should take into account the respective effects of fetal number and sex to provide more detailed insights into the mechanisms by which adipose and related tissues can be programmed in utero. Copyright © 2016 Elsevier Inc. All rights reserved.

White adipose tissue genome wide-expression profiling and adipocyte metabolic functions after soy protein consumption in rats.

PubMed

Frigolet, Maria E; Torres, Nimbe; Uribe-Figueroa, Laura; Rangel, Claudia; Jimenez-Sanchez, Gerardo; Tovar, Armando R

2011-02-01

Obesity is associated with an increase in adipose tissue mass due to an imbalance between high dietary energy intake and low physical activity; however, the type of dietary protein may contribute to its development. The aim of the present work was to study the effect of soy protein versus casein on white adipose tissue genome profiling, and the metabolic functions of adipocytes in rats with diet-induced obesity. The results showed that rats fed a Soy Protein High-Fat (Soy HF) diet gained less weight and had lower serum leptin concentration than rats fed a Casein High-Fat (Cas HF) diet, despite similar energy intake. Histological studies indicated that rats fed the Soy HF diet had significantly smaller adipocytes than those fed the Cas HF diet, and this was associated with a lower triglyceride/DNA content. Fatty acid synthesis in isolated adipocytes was reduced by the amount of fat consumed but not by the type of protein ingested. Expression of genes of fatty acid oxidation increased in adipose tissue of rats fed Soy diets; microarray analysis revealed that Soy protein consumption modified the expression of 90 genes involved in metabolic functions and inflammatory response in adipose tissue. Network analysis showed that the expression of leptin was regulated by the type of dietary protein and it was identified as a central regulator of the expression of lipid metabolism genes in adipose tissue. Thus, soy maintains the size and metabolic functions of adipose tissue through biochemical adaptations, adipokine secretion, and global changes in gene expression. Copyright © 2011 Elsevier Inc. All rights reserved.

A Weight-Loss Diet Including Coffee-Derived Mannooligosaccharides Enhances Adipose Tissue Loss in Overweight Men but Not Women

PubMed Central

St-Onge, Marie-Pierre; Salinardi, Taylor; Herron-Rubin, Kristin; Black, Richard M.

2013-01-01

Mannooligosaccharides (MOS), extracted from coffee, have been shown to promote a decrease in body fat when consumed as part of free-living, weight-maintaining diets. Our objective was to determine if MOS consumption (4 g/day), in conjunction with a weight-loss diet, would lead to greater reductions in adipose tissue compartments than placebo. We conducted a double-blind, placebo-controlled weight-loss study in which 60 overweight men and women consumed study beverages and received weekly group counseling for 12 weeks. Weight and blood pressure were measured weekly, and adipose tissue distribution was assessed at baseline and at end point using magnetic resonance imaging. A total of 54 subjects completed the study. Men consuming the MOS beverage had greater loss of body weight than men consuming the Placebo beverage (−6.0 ± 0.6% vs. −2.3 ± 0.5%, respectively, P < 0.05). Men consuming the MOS beverage also had reductions in total body volume (P < 0.0001), total (P < 0.0001), subcutaneous (P < 0.0001), and visceral (P < 0.05) adipose tissue that were greater than changes observed in those consuming the Placebo beverage. In women, changes in body weight and adipose tissue compartments were not different between groups. Adding coffee-derived MOS to a weight-loss diet enhanced both weight and adipose tissue losses in men, suggesting a potential functional use of MOS for weight management and improvement in adipose tissue distribution. More studies are needed to investigate the apparent gender difference in response to MOS consumption. PMID:21938072

Sex-dependent effects of neonatal maternal deprivation on endocannabinoid levels in the adipose tissue: influence of diet.

PubMed

Mela, Virginia; Piscitelli, Fabiana; Berzal, Alvaro Llorente; Chowen, Julie; Silvestri, Cristoforo; Viveros, Maria Paz; Di Marzo, Vincenzo

2016-08-01

Maternal deprivation (MD) during neonatal life has diverse long-term effects, including modification of metabolism. We have previously reported that MD modifies the metabolic response to high-fat diet (HFD) intake, with this response being different between males and females, while previous studies indicate that in mice with HFD-induced obesity, endocannabinoid (EC) levels are markedly altered in various brown and white adipose tissue depots. Here, we analyzed the effects of MD (24 h at postnatal day 9), alone or in combination with a HFD from weaning until the end of the experiment in Wistar rats of both sexes. Brown and white perirenal and subcutaneous adipose tissues were collected and the levels of anandamide (AEA), 2-arachidonoylglycerol (2-AG), palmitoylethanolamide (PEA), and oleoylethanolamide (OEA) were determined. In males, MD increased the content of OEA in brown and 2-AG in subcutaneous adipose tissues, while in females the content of 2-AG was increased in perirenal fat. Moreover, in females, MD decreased AEA and OEA levels in perirenal and subcutaneous adipose tissues, respectively. HFD decreased the content of 2-AG in brown fat of both sexes and OEA in brown and subcutaneous adipose tissue of control females. In contrast, in subcutaneous fat, HFD increased AEA levels in MD males and OEA levels in control and MD males. The present results show for the first time that MD and HFD induce sex-dependent effects on the main ECs, AEA, and 2-AG, and of AEA-related mediators, OEA and PEA, in the rat brown and white (visceral and subcutaneous) adipose tissues.

Cancer-adipose tissue interaction and fluid flow synergistically modulate cell kinetics, HER2 expression, and trastuzumab efficacy in gastric cancer.

PubMed

Akutagawa, Takashi; Aoki, Shigehisa; Yamamoto-Rikitake, Mihoko; Iwakiri, Ryuichi; Fujimoto, Kazuma; Toda, Shuji

2018-04-25

Early local tumor invasion in gastric cancer results in likely encounters between cancer cells and submucosal and subserosal adipose tissue, but these interactions remain to be clarified. Microenvironmental mechanical forces, such as fluid flow, are known to modulate normal cell kinetics, but the effects of fluid flow on gastric cancer cells are poorly understood. We analyzed the cell kinetics and chemosensitivity in gastric cancer using a simple in vitro model that simultaneously replicated the cancer-adipocyte interaction and physical microenvironment. Gastric cancer cells (MKN7 and MKN74) were seeded on rat adipose tissue fragment-embedded discs or collagen discs alone. To generate fluid flow, samples were placed on a rotatory shaker in a CO 2 incubator. Proliferation, apoptosis, invasion, and motility-related molecules were analyzed by morphometry and immunostaining. Proteins were evaluated by western blot analysis. Chemosensitivity was investigated by trastuzumab treatment. Adipose tissue and fluid flow had a positive synergistic effect on the proliferative potential and invasive capacity of gastric cancer cells, and adipose tissue inhibited apoptosis in these cells. Adipose tissue upregulated ERK1/2 signaling in gastric cancer cells, but downregulated p38 signaling. Notably, adipose tissue and fluid flow promoted membranous and cytoplasmic HER2 expression and modulated chemosensitivity to trastuzumab in gastric cancer cells. We have demonstrated that cancer-adipocyte interaction and physical microenvironment mutually modulate gastric cancer cell kinetics. Further elucidation of the microenvironmental regulation in gastric cancer will be very important for the development of strategies involving molecular targeted therapy.

Enhanced Inflammation without Impairment of Insulin Signaling in the Visceral Adipose Tissue of 5α-Dihydrotestosterone-Induced Animal Model of Polycystic Ovary Syndrome.

PubMed

Milutinović, Danijela Vojnović; Nikolić, Marina; Veličković, Nataša; Djordjevic, Ana; Bursać, Biljana; Nestorov, Jelena; Teofilović, Ana; Antić, Ivana Božić; Macut, Jelica Bjekić; Zidane, Abdulbaset Shirif; Matić, Gordana; Macut, Djuro

2017-09-01

Polycystic ovary syndrome is a heterogeneous endocrine and metabolic disorder associated with abdominal obesity, dyslipidemia and insulin resistance. Since abdominal obesity is characterized by low-grade inflammation, the aim of the study was to investigate whether visceral adipose tissue inflammation linked to abdominal obesity and dyslipidemia could lead to impaired insulin sensitivity in the animal model of polycystic ovary syndrome.Female Wistar rats were treated with nonaromatizable 5α-dihydrotestosterone pellets in order to induce reproductive and metabolic characteristics of polycystic ovary syndrome. Glucose, triglycerides, non-esterified fatty acids and insulin were determined in blood plasma. Visceral adipose tissue inflammation was evaluated by the nuclear factor kappa B intracellular distribution, macrophage migration inhibitory factor protein level, as well as TNFα, IL6 and IL1β mRNA levels. Insulin sensitivity was assessed by intraperitoneal glucose tolerance test and homeostasis model assessment index, and through analysis of insulin signaling pathway in the visceral adipose tissue.Dihydrotestosterone treatment led to increased body weight, abdominal obesity and elevated triglycerides and non-esterified fatty acids, which were accompanied by the activation of nuclear factor kappa B and increase in macrophage migration inhibitory factor, IL6 and IL1β levels in the visceral adipose tissue. In parallel, insulin sensitivity was affected in 5α-dihydrotestosterone-treated animals only at the systemic and not at the level of visceral adipose tissue.The results showed that abdominal obesity and dyslipidemia in the animal model of polycystic ovary syndrome were accompanied with low-grade inflammation in the visceral adipose tissue. However, these metabolic disturbances did not result in decreased tissue insulin sensitivity. © Georg Thieme Verlag KG Stuttgart · New York.

Protein Kinase A Regulatory Subunits in Human Adipose Tissue

PubMed Central

Mantovani, Giovanna; Bondioni, Sara; Alberti, Luisella; Gilardini, Luisa; Invitti, Cecilia; Corbetta, Sabrina; Zappa, Marco A.; Ferrero, Stefano; Lania, Andrea G.; Bosari, Silvano; Beck-Peccoz, Paolo; Spada, Anna

2009-01-01

OBJECTIVE—In human adipocytes, the cAMP-dependent pathway mediates signals originating from β-adrenergic activation, thus playing a key role in the regulation of important metabolic processes, i.e., lipolysis and thermogenesis. Cyclic AMP effects are mainly mediated by protein kinase A (PKA), whose R2B regulatory isoform is the most expressed in mouse adipose tissue, where it protects against diet-induced obesity and fatty liver development. The aim of the study was to investigate possible differences in R2B expression, PKA activity, and lipolysis in adipose tissues from obese and nonobese subjects. RESEARCH DESIGN AND METHODS—The expression of the different PKA regulatory subunits was evaluated by immunohistochemistry, Western blot, and real-time PCR in subcutaneous and visceral adipose tissue samples from 20 nonobese and 67 obese patients. PKA activity and glycerol release were evaluated in total protein extract and adipocytes isolated from fresh tissue samples, respectively. RESULTS—Expression techniques showed that R2B was the most abundant regulatory protein, both at mRNA and protein level. Interestingly, R2B mRNA levels were significantly lower in both subcutaneous and visceral adipose tissues from obese than nonobese patients and negatively correlated with BMI, waist circumference, insulin levels, and homeostasis model assessment of insulin resistance. Moreover, both basal and stimulated PKA activity and glycerol release were significantly lower in visceral adipose tissue from obese patients then nonobese subjects. CONCLUSIONS—Our results first indicate that, in human adipose tissue, there are important BMI-related differences in R2B expression and PKA activation, which might be included among the multiple determinants involved in the different lipolytic response to β-adrenergic activation in obesity. PMID:19095761

The peritumoural adipose tissue microenvironment and cancer. The roles of fatty acid binding protein 4 and fatty acid binding protein 5.

PubMed

Guaita-Esteruelas, S; Gumà, J; Masana, L; Borràs, J

2018-02-15

The adipose tissue microenvironment plays a key role in tumour initiation and progression because it provides fatty acids and adipokines to tumour cells. The fatty acid-binding protein (FABP) family is a group of small proteins that act as intracellular fatty acid transporters. Adipose-derived FABPs include FABP4 and FABP5. Both have an important role in lipid-related metabolic processes and overexpressed in many cancers, such as breast, prostate, colorectal and ovarian. Moreover, their expression in peritumoural adipose tissue is deregulated, and their circulating levels are upregulated in some tumours. In this review, we discuss the role of the peritumoural adipose tissue and the related adipokines FABP4 and FABP5 in cancer initiation and progression and the possible pathways implicated in these processes. Copyright © 2017 Elsevier B.V. All rights reserved.

Depot-dependent effects of adipose tissue explants on co-cultured hepatocytes.

PubMed

Du, Zhen-Yu; Ma, Tao; Lock, Erik-Jan; Hao, Qin; Kristiansen, Karsten; Frøyland, Livar; Madsen, Lise

2011-01-01

We have developed an in vitro hepatocyte-adipose tissue explant (ATE) co-culture model enabling examination of the effect of visceral and subcutaneous adipose tissues on primary rat hepatocytes. Initial analyses of inflammatory marker genes were performed in fractionated epididymal or inguinal adipose tissues. Expressions of inflammation related genes (IL-6, TNF-α, COX-2) were higher in the inguinal than the epididymal ATE. Similarly, expressions of marker genes of macrophage and monocyte (MPEG-1, CD68, F4/80, CD64) were higher in the stromal vascular fraction (SVF) isolated from inguinal ATE than that from epididymal ATE. However, expressions of lipolysis related genes (ATGL, HSL, perilipin-1) were higher in the epididymal adipocytes than inguinal adipocytes. Moreover, secretion of IL-6 and PGE(2) was higher from inguinal ATEs than from epididymal ATEs. There was a trend that the total levels of IL-6, TNF-α and PGE(2) in the media from inguinal ATEs co-cultured with primary rat hepatocytes were higher than that in the media from epididymal ATEs co-cultured with hepatocytes, although the significant difference was only seen in PGE(2). Lipolysis, measured as glycerol release, was similar in the ATEs isolated from inguinal and epididymal adipose tissues when cultured alone, but the glycerol release was higher in the ATEs isolated from epididymal than from inguinal adipose tissue when co-cultured with hepatocytes. Compared to epididymal ATEs, the ATEs from inguinal adipose tissue elicited a stronger cytotoxic response and higher level of insulin resistance in the co-cultured hepatocytes. In conclusion, our results reveal depot-dependent effects of ATEs on co-cultured primary hepatocytes, which in part may be related to a more pronounced infiltration of stromal vascular cells (SVCs), particularly macrophages, in inguinal adipose tissue resulting in stronger responses in terms of hepatotoxicity and insulin-resistance.

Role of innate immune receptors TLR2 and TLR4 as mediators of the inflammatory reaction in human visceral adipose tissue.

PubMed

Fusaru, Ana Marina; Stănciulescu, Camelia Elena; Surlin, V; Taisescu, C; Bold, Adriana; Pop, O T; Baniţă, Ileana Monica; Crăiţoiu, Stefania; Pisoschi, Cătălina Gabriela

2012-01-01

White adipose tissue from different locations is characterized by significant differences in the structure of adipocyte "secretoma". Fat accumulation in the central-visceral depots is usually associated with a chronic inflammatory state, which is complicated by the metabolic syndrome. Recently, the adipose tissue was emerged to have an essential role in the innate immunity, adipocytes being considered effector cells due to the presence of the Toll-like receptors (TLRs). In this study, we compared the expression of TNF-α, TLR2 and TLR4 in peripheral-subcutaneous and central-peritoneal adipose depots in three different conditions - lean, obese and obese diabetic - using immunohistochemistry. Our results suggest a correlation between the incidence of the stromal vascular cells and adipocytes TNF-α and TLR4 in the visceral depots in strong correlation with adipose tissue expansion. TLR2 positive cells were seen in the peripheral depots from all groups without any association with fat accumulation. These results focus on the existence of a new pathogenic pathway, the activation of TLR4, for the involvement of visceral adipose tissue in the activation and maintenance of the inflammatory cascade in obesity.

Uncultivated stromal vascular fraction is equivalent to adipose-derived stem and stromal cells on porous polyurethrane scaffolds forming adipose tissue in vivo.

PubMed

Griessl, Michael; Buchberger, Anna-Maria; Regn, Sybille; Kreutzer, Kilian; Storck, Katharina

2018-06-01

To find an alternative approach to contemporary techniques in tissue augmentation and reconstruction, tissue engineering strategies aim to involve adipose-derived stem and stromal cells (ASCs) harboring a strong differentiation potential into various tissue types such as bone, cartilage, and fat. Animal research. The stromal vascular fraction (SVF) was used directly as a cell source to provide a potential alternative to contemporary ASC-based adipose tissue engineering. Seeded in TissuCol fibrin, we applied ASCs or SVF cells to porous, degradable polyurethane (PU) scaffolds. We successfully demonstrated the in vivo generation of volume-stable, well-vascularized PU-based constructs containing host-derived mature fat pads. Seeded human stem cells served as modulators of host-cell migration rather than differentiating themselves. We further demonstrated that preliminary culture of SVF cells was not necessary. Our results bring adipose tissue engineering, together with automated processing devices, closer to clinical applicability. The time-consuming and cost-intensive culture and induction of the ASCs is not necessary. NA. Laryngoscope, 128:E206-E213, 2018. © 2018 The American Laryngological, Rhinological and Otological Society, Inc.

Role of arsenic exposure in adipose tissue dysfunction and its possible implication in diabetes pathophysiology.

PubMed

Renu, Kaviyarasi; Madhyastha, Harishkumar; Madhyastha, Radha; Maruyama, Masugi; Arunachlam, Sankarganesh; V G, Abilash

2018-03-01

Exposure to arsenic in drinking water can stimulate a diverse number of diseases that originate from impaired lipid metabolism in adipose and glucose metabolism, leading to insulin resistance. Arsenic inhibits differentiation of adipocyte and mediates insulin resistance with diminutive information on arsenicosis on lipid storage and lipolysis. This review focused on different mechanisms and pathways involved in adipogenesis and lipolysis in adipose tissue during arsenic-induced diabetes. Though arsenic is known to cause type2 diabetes through different mechanisms, the role of adipose tissue in causing type2 diabetes is still unclear. With the existing literature, this review exhibits the effect of arsenic on adipose tissue and its signalling events such as SIRT3- FOXO3a signalling pathway, Ras -MAP -AP-1 cascade, PI(3)-K-Akt pathway, endoplasmic reticulum stress protein, C/EBP homologous protein (CHOP10) and GPCR pathway with role of adipokines. There is a need to elucidate the different types of adipokines which are involved in arsenic-induced diabetes. The exhibited information brings to light that arsenic has negative effects on a white adipose tissue (WAT) by decreasing adipogenesis and enhancing lipolysis. Some of the epidemiological studies show that arsenic would causes obesity. Few studies indicate that arsenic might induces lipodystrophy condition. Further research is needed to evaluate the mechanistic link between arsenic and adipose tissue dysfunction which leads to insulin resistance. Copyright © 2017 Elsevier B.V. All rights reserved.

Vitamin D and adipose tissue-more than storage.

PubMed

Mutt, Shivaprakash J; Hyppönen, Elina; Saarnio, Juha; Järvelin, Marjo-Riitta; Herzig, Karl-Heinz

2014-01-01

The pandemic increase in obesity is inversely associated with vitamin D levels. While a higher BMI was causally related to lower 25-hydroxyvitamin D (25(OH)D), no evidence was obtained for a BMI lowering effect by higher 25(OH)D. Some of the physiological functions of 1,25(OH)2D3 (1,25-dihydroxycholecalciferol or calcitriol) via its receptor within the adipose tissue have been investigated such as its effect on energy balance, adipogenesis, adipokine, and cytokine secretion. Adipose tissue inflammation has been recognized as the key component of metabolic disorders, e.g., in the metabolic syndrome. The adipose organ secretes more than 260 different proteins/peptides. However, the molecular basis of the interactions of 1,25(OH)2D3, vitamin D binding proteins (VDBPs) and nuclear vitamin D receptor (VDR) after sequestration in adipose tissue and their regulations are still unclear. 1,25(OH)2D3 and its inactive metabolites are known to inhibit the formation of adipocytes in mouse 3T3-L1 cell line. In humans, 1,25(OH)2D3 promotes preadipocyte differentiation under cell culture conditions. Further evidence of its important functions is given by VDR knock out (VDR(-/-)) and CYP27B1 knock out (CYP27B1 (-/-)) mouse models: Both VDR(-/-) and CYP27B1(-/-) models are highly resistant to the diet induced weight gain, while the specific overexpression of human VDR in adipose tissue leads to increased adipose tissue mass. The analysis of microarray datasets from human adipocytes treated with macrophage-secreted products up-regulated VDR and CYP27B1 genes indicating the capacity of adipocytes to even produce active 1,25(OH)2D3. Experimental studies demonstrate that 1,25(OH)2D3 has an active role in adipose tissue by modulating inflammation, adipogenesis and adipocyte secretion. Yet, further in vivo studies are needed to address the effects and the effective dosages of vitamin D in human adipose tissue and its relevance in the associated diseases.

Identification of Regulatory Elements That Control PPARγ Expression in Adipocyte Progenitors

PubMed Central

Chou, Wen-Ling; Galmozzi, Andrea; Partida, David; Kwan, Kevin; Yeung, Hui; Su, Andrew I.; Saez, Enrique

2013-01-01

Adipose tissue renewal and obesity-driven expansion of fat cell number are dependent on proliferation and differentiation of adipose progenitors that reside in the vasculature that develops in coordination with adipose depots. The transcriptional events that regulate commitment of progenitors to the adipose lineage are poorly understood. Because expression of the nuclear receptor PPARγ defines the adipose lineage, isolation of elements that control PPARγ expression in adipose precursors may lead to discovery of transcriptional regulators of early adipocyte determination. Here, we describe the identification and validation in transgenic mice of 5 highly conserved non-coding sequences from the PPARγ locus that can drive expression of a reporter gene in a manner that recapitulates the tissue-specific pattern of PPARγ expression. Surprisingly, these 5 elements appear to control PPARγ expression in adipocyte precursors that are associated with the vasculature of adipose depots, but not in mature adipocytes. Characterization of these five PPARγ regulatory sequences may enable isolation of the transcription factors that bind these cis elements and provide insight into the molecular regulation of adipose tissue expansion in normal and pathological states. PMID:24009687

Current Therapeutic Strategies for Adipose Tissue Defects/Repair Using Engineered Biomaterials and Biomolecule Formulations.

PubMed

Mahoney, Christopher M; Imbarlina, Cayla; Yates, Cecelia C; Marra, Kacey G

2018-01-01

Tissue engineered scaffolds for adipose restoration/repair has significantly evolved in recent years. Patients requiring soft tissue reconstruction, caused by defects or pathology, require biomaterials that will restore void volume with new functional tissue. The gold standard of autologous fat grafting (AFG) is not a reliable option. This review focuses on the latest therapeutic strategies for the treatment of adipose tissue defects using biomolecule formulations and delivery, and specifically engineered biomaterials. Additionally, the clinical need for reliable off-the-shelf therapies, animal models, and challenges facing current technologies are discussed.

Distinct effects of calorie restriction on adipose tissue cytokine and angiogenesis profiles in obese and lean mice

PubMed Central

2012-01-01

Background Obesity associates with low-grade inflammation and adipose tissue remodeling. Using sensitive high-throughput protein arrays we here investigated adipose tissue cytokine and angiogenesis-related protein profiles from obese and lean mice, and in particular, the influence of calorie restriction (CR). Methods Tissue samples from visceral fat were harvested from obese mice fed with a high-fat diet (60% of energy), lean controls receiving low-fat control diet as well as from obese and lean mice kept under CR (energy intake 70% of ad libitum intake) for 50 days. Protein profiles were analyzed using mouse cytokine and angiogenesis protein array kits. Results In obese and lean mice, CR was associated with 11.3% and 15.6% reductions in body weight, as well as with 4.0% and 4.6% reductions in body fat percentage, respectively. Obesity induced adipose tissue cytokine expressions, the most highly upregulated cytokines being IL-1ra, IL-2, IL-16, MCP-1, MIG, RANTES, C5a, sICAM-1 and TIMP-1. CR increased sICAM-1 and TIMP-1 expression both in obese and lean mice. Overall, CR showed distinct effects on cytokine expressions; in obese mice CR largely decreased but in lean mice increased adipose tissue cytokine expressions. Obesity was also associated with increased expressions of angiogenesis-related proteins, in particular, angiogenin, endoglin, endostatin, endothelin-1, IGFBP-3, leptin, MMP-3, PAI-1, TIMP-4, CXCL16, platelet factor 4, DPPIV and coagulation factor III. CR increased endoglin, endostatin and platelet factor 4 expressions, and decreased IGFBP-3, NOV, MMP-9, CXCL16 and osteopontin expressions both in obese and lean mice. Interestingly, in obese mice, CR decreased leptin and TIMP-4 expressions, whereas in lean mice their expressions were increased. CR decreased MMP-3 and PAI-1 only in obese mice, whereas CR decreased FGF acidic, FGF basic and coagulation factor III, and increased angiogenin and DPPIV expression only in lean mice. Conclusions CR exerts distinct effects on adipocyte cytokine and angiogenesis profiles in obese and lean mice. Our study also underscores the importance of angiogenesis-related proteins and cytokines in adipose tissue remodeling and development of obesity. PMID:22748184

Mycobacterium tuberculosis infection modulates adipose tissue biology

PubMed Central

Kühl, Anja A.; Kupz, Andreas; Vogelzang, Alexis; Mollenkopf, Hans-Joachim; Löwe, Delia; Bandermann, Silke; Dorhoi, Anca; Brinkmann, Volker

2017-01-01

Mycobacterium tuberculosis (Mtb) primarily resides in the lung but can also persist in extrapulmonary sites. Macrophages are considered the prime cellular habitat in all tissues. Here we demonstrate that Mtb resides inside adipocytes of fat tissue where it expresses stress-related genes. Moreover, perigonadal fat of Mtb-infected mice disseminated the infection when transferred to uninfected animals. Adipose tissue harbors leukocytes in addition to adipocytes and other cell types and we observed that Mtb infection induces changes in adipose tissue biology depending on stage of infection. Mice infected via aerosol showed infiltration of inducible nitric oxide synthase (iNOS) or arginase 1 (Arg1)-negative F4/80+ cells, despite recruitment of CD3+, CD4+ and CD8+ T cells. Gene expression analysis of adipose tissue of aerosol Mtb-infected mice provided evidence for upregulated expression of genes associated with T cells and NK cells at 28 days post-infection. Strikingly, IFN-γ-producing NK cells and Mtb-specific CD8+ T cells were identified in perigonadal fat, specifically CD8+CD44-CD69+ and CD8+CD44-CD103+ subpopulations. Gene expression analysis of these cells revealed that they expressed IFN-γ and the lectin-like receptor Klrg1 and down-regulated CD27 and CD62L, consistent with an effector phenotype of Mtb-specific CD8+ T cells. Sorted NK cells expressed higher abundance of Klrg1 upon infection, as well. Our results reveal the ability of Mtb to persist in adipose tissue in a stressed state, and that NK cells and Mtb-specific CD8+ T cells infiltrate infected adipose tissue where they produce IFN-γ and assume an effector phenotype. We conclude that adipose tissue is a potential niche for Mtb and that due to infection CD8+ T cells and NK cells are attracted to this tissue. PMID:29040326

Injectable Hydrogel Scaffold from Decellularized Human Lipoaspirate

PubMed Central

Young, D. Adam; Ibrahim, Dina O.; Hu, Diane; Christman, Karen L.

2010-01-01

Soft tissue fillers are rapidly gaining popularity for aesthetic improvements or repair of adipose tissue deficits. Several injectable biopolymers have been investigated for this purpose but often face rapid resorption or limited adipogenesis, and do not mimic the native adipose extracellular matrix (ECM). We have generated an injectable adipose matrix scaffold by efficiently removing both the cellular and lipid contents of human lipoaspirate. The decellularized material retained a complex composition of peptides and glycosaminoglycans found in native adipose ECM. This matrix can be further processed by solubilizing the extracted ECM to generate a thermally-responsive hydrogel that self-assembles upon subcutaneous injection. This hydrogel also supports the growth and survival of patient matched adipose - derived stem cells in vitro. The development of an injectable hydrogel from human lipoaspirate represents a minimally-invasive option for adipose tissue engineering in terms of both the collection of source material and delivery of the scaffold. PMID:20932943

Effects of Male Hypogonadism on Regional Adipose Tissue Fatty Acid Storage and Lipogenic Proteins

PubMed Central

Santosa, Sylvia; Jensen, Michael D.

2012-01-01

Testosterone has long been known to affect body fat distribution, although the underlying mechanisms remain elusive. We investigated the effects of chronic hypogonadism in men on adipose tissue fatty acid (FA) storage and FA storage factors. Twelve men with chronic hypogonadism and 13 control men matched for age and body composition: 1) underwent measures of body composition with dual energy x-ray absorptiometry and an abdominal CT scan; 2) consumed an experimental meal containing [3H]triolein to determine the fate of meal FA (biopsy-measured adipose storage vs. oxidation); 3) received infusions of [U-13C]palmitate and [1-14C]palmitate to measure rates of direct free (F)FA storage (adipose biopsies). Adipose tissue lipoprotein lipase, acyl-CoA synthetase (ACS), and diacylglycerol acetyl-transferase (DGAT) activities, as well as, CD36 content were measured to understand the mechanism by which alterations in fat storage occur in response to testosterone deficiency. Results of the study showed that hypogonadal men stored a greater proportion of both dietary FA and FFA in lower body subcutaneous fat than did eugonadal men (both p<0.05). Femoral adipose tissue ACS activity was significantly greater in hypogonadal than eugonadal men, whereas CD36 and DGAT were not different between the two groups. The relationships between these proteins and FA storage varied somewhat between the two groups. We conclude that chronic effects of testosterone deficiency has effects on leg adipose tissue ACS activity which may relate to greater lower body FA storage. These results provide further insight into the role of androgens in body fat distribution and adipose tissue metabolism in humans. PMID:22363653

Changes of noradrenergic activity and lipolysis in the subcutaneous abdominal adipose tissue of hypo- and hyperthyroid patients: an in vivo microdialysis study.

PubMed

Nedvidkova, Jara; Haluzik, Martin; Bartak, Vladimir; Dostalova, Ivana; Vlcek, Petr; Racek, Pavel; Taus, Michal; Behanova, Magdalena; Svacina, Stepan; Alesci, Salvatore; Pacak, Karel

2004-06-01

Thyroid function plays an important role in the regulation of overall metabolic rate and lipid metabolism. However, it is uncertain whether thyroid hormones directly affect lipolysis in adipose tissue and to what extent those changes contribute to overall metabolic phenotype. Our study was designed, using the microdialysis technique, to determine basal and isoprenaline-stimulated local lipolysis and to determine local concentrations of lipolysis-regulating catecholamines in abdominal subcutaneous adipose tissue in 12 patients with hypothyroidism, 6 patients with hyperthyroidism, and 12 healthy control subjects. Plasma norepinephrine (NE) concentrations in hypothyroid subjects were significantly higher than in the control and hyperthyroid groups. In contrast, systemic, adipose NE levels in hypothyroid patients were decreased relative to controls. Hyperthyroidism, on the other hand, resulted in four-fold higher adipose NE levels. Basal lipolysis measured by glycerol concentrations in adipose tissue was significantly attenuated in hypothyroid patients and markedly increased in hyperthyroid patients in comparison with the control group. In addition to differences in basal lipolysis, hypothyroidism resulted in attenuated, and hyperthyroidism in enhanced, lipolytic response to local stimulation with beta(1,2)-adrenergic agonist isoprenaline. These results demonstrate that lipolysis in abdominal subcutaneous adipose tissue is strongly modulated by thyroid function. We suggest that thyroid hormones regulate lipolysis primarily by affecting local NE concentration and/or adrenergic postreceptor signaling.

Adipose tissue inflammation and reduced insulin sensitivity in ovariectomized mice occurs in the absence of increased adiposity

USDA-ARS?s Scientific Manuscript database

Menopause promotes central obesity, adipose tissue (AT) inflammation and insulin resistance (IR). Both obesity and the loss of estrogen can activate innate and adaptive immune cells (macrophages (M's), T-cells). The respective impacts of weight gain and loss of ovarian hormones on AT inflammation an...

Carotenoids in Adipose Tissue Biology and Obesity.

PubMed

Bonet, M Luisa; Canas, Jose A; Ribot, Joan; Palou, Andreu

2016-01-01

Cell, animal and human studies dealing with carotenoids and carotenoid derivatives as nutritional regulators of adipose tissue biology with implications for the etiology and management of obesity and obesity-related metabolic diseases are reviewed. Most studied carotenoids in this context are β-carotene, cryptoxanthin, astaxanthin and fucoxanthin, together with β-carotene-derived retinoids and some other apocarotenoids. Studies indicate an impact of these compounds on essential aspects of adipose tissue biology including the control of adipocyte differentiation (adipogenesis), adipocyte metabolism, oxidative stress and the production of adipose tissue-derived regulatory signals and inflammatory mediators. Specific carotenoids and carotenoid derivatives restrain adipogenesis and adipocyte hypertrophy while enhancing fat oxidation and energy dissipation in brown and white adipocytes, and counteract obesity in animal models. Intake, blood levels and adipocyte content of carotenoids are reduced in human obesity. Specifically designed human intervention studies in the field, though still sparse, indicate a beneficial effect of carotenoid supplementation in the accrual of abdominal adiposity. In summary, studies support a role of specific carotenoids and carotenoid derivatives in the prevention of excess adiposity, and suggest that carotenoid requirements may be dependent on body composition.

Obesity Disrupts Rhythmic Clock Gene Expression in Maternal Adipose Tissue during Rat Pregnancy.

PubMed

Crew, Rachael C; Mark, Peter J; Waddell, Brendan J

2018-06-01

Obesity during pregnancy causes numerous maternal and fetal health complications, but the underlying mechanisms remain unclear. Adipose tissue dysfunction in obesity has previously been linked to disruption of the intrinsic adipose clock gene network that is crucial for normal metabolic function. This adipose clock also undergoes major change as part of the maternal metabolic adaptation to pregnancy, but whether this is affected by maternal obesity is unknown. Consequently, in this study we tested the hypothesis that obesity disturbs rhythmic gene expression in maternal adipose tissue across pregnancy. A rat model of maternal obesity was established by cafeteria (CAF) feeding, and adipose expression of clock genes and associated nuclear receptors ( Ppars and Pgc1α) was measured across days 15-16 and 21-22 of gestation (term = 23 days). CAF feeding suppressed the mesor and/or amplitude of adipose tissue clock genes (most notably Bmal1, Per2, and Rev-erbα) relative to chow-fed controls (CON) across both days of gestation. On day 15, the CAF diet also induced adipose Pparα, Pparδ, and Pgc1α rhythmicity but repressed that of Pparγ, while expression of Pparα, Pparδ, and Pgc1α was reduced at select time points. CAF mothers were hyperleptinemic at both stages of gestation, and at day 21 this effect was time-of-day dependent. Fetal plasma leptin exhibited clear rhythmicity, albeit with low amplitude, but interestingly these levels were unaffected by CAF feeding. Our data show that maternal obesity disrupts rhythmic expression of clock and metabolic genes in maternal adipose tissue and leads to maternal but not fetal hyperleptinemia.

Effects of Erythropoietin on Adipose Tissue: A Possible Strategy in Refilling

PubMed Central

Sabbatini, Maurizio; Bosetti, Michela; Borrone, Alessia; Boldorini, Renzo; Taveggia, Antonio; Verna, Giovanni; Cannas, Mario

2015-01-01

Background: The increased resorption and the difficulty of the fat graft take following autologous fat transplantation procedure are associated with reduced fat tissue revascularization and increased apoptosis of adipose cells. We suppose that the lipofilling procedure induces an inflammatory environment within the fat graft mass, whose evolution influences the efficacy of autologous fat graft survival. Erythropoietin (EPO) is a glycoprotein hormone known to exert angiogenetic and anti-inflammatory effects; therefore, our purpose was to investigate its reaction with adipose tissue used in lipofilling. Methods: Fat masses were harvested using manual suction lipectomy and then seeded on dishes in appropriate culture and treated for 3 weeks with 3 doses of EPO. CD31 and CD68 immunohistochemistry was used to identify microvessels and several infiltrating leukocyte cells. Results: Following EPO administration, we have detected an increase in the number of CD31-positive microvessel endothelium cells and CD31-positive small leukocytes and a reduction of CD68-positive cells. These effects were more conspicuous following higher EPO dose. Conclusions: Our findings evidence EPO treatment as a useful strategy to sustain the revascularization of grafted tissue and to reduce its inflammatory state. PMID:26034645

Novel macro-microporous gelatin scaffold fabricated by particulate leaching for soft tissue reconstruction with adipose-derived stem cells.

PubMed

Phull, Manraj K; Eydmann, Trevor; Roxburgh, Judy; Sharpe, Justin R; Lawrence-Watt, Diana J; Phillips, Gary; Martin, Yella

2013-02-01

The restoration of body contours as shaped by adipose tissue remains a clinical challenge specifically in patients who have experienced loss of contour due to trauma, surgical removal of tumours or congenital abnormalities. We have developed a novel macro-microporous biomaterial for use in soft tissue re-bulking and augmentation. Alginate beads provided the pore template for the construct. Incorporation, and subsequent dissolution, of the beads within a 7 % (w/v) gelatin matrix, produced a highly porous scaffold with an average pore size of 2.01 ± 0.08 mm. The ability of this scaffold to support the in vitro growth and differentiation of human adipose-derived stem cells (ADSCs) was then investigated. Histological analysis confirmed that the scaffold itself provided a suitable environment to support the growth of ADSCs on the scaffold walls. When delivered into the macropores in a fibrin hydrogel, ADSCs proliferated and filled the pores. In addition, ADSCs could readily be differentiated along the adipogenic lineage. These results therefore describe a novel scaffold that can support the proliferation and delivery of ADSCs. The scaffold is the first stage in developing a clinical alternative to current treatment methods for soft tissue reconstruction.

Quantitative analysis of adipose tissue on chest CT to predict primary graft dysfunction in lung transplant recipients: a novel optimal biomarker approach

NASA Astrophysics Data System (ADS)

Tong, Yubing; Udupa, Jayaram K.; Wang, Chuang; Wu, Caiyun; Pednekar, Gargi; Restivo, Michaela D.; Lederer, David J.; Christie, Jason D.; Torigian, Drew A.

2018-02-01

In this study, patients who underwent lung transplantation are categorized into two groups of successful (positive) or failed (negative) transplantations according to primary graft dysfunction (PGD), i.e., acute lung injury within 72 hours of lung transplantation. Obesity or being underweight is associated with an increased risk of PGD. Adipose quantification and characterization via computed tomography (CT) imaging is an evolving topic of interest. However, very little research of PGD prediction using adipose quantity or characteristics derived from medical images has been performed. The aim of this study is to explore image-based features of thoracic adipose tissue on pre-operative chest CT to distinguish between the above two groups of patients. 140 unenhanced chest CT images from three lung transplant centers (Columbia, Penn, and Duke) are included in this study. 124 patients are in the successful group and 16 in failure group. Chest CT slices at the T7 and T8 vertebral levels are captured to represent the thoracic fat burden by using a standardized anatomic space (SAS) approach. Fat (subcutaneous adipose tissue (SAT)/ visceral adipose tissue (VAT)) intensity and texture properties (1142 in total) for each patient are collected, and then an optimal feature set is selected to maximize feature independence and separation between the two groups. Leave-one-out and leave-ten-out crossvalidation strategies are adopted to test the prediction ability based on those selected features all of which came from VAT texture properties. Accuracy of prediction (ACC), sensitivity (SEN), specificity (SPE), and area under the curve (AUC) of 0.87/0.97, 0.87/0.97, 0.88/1.00, and 0.88/0.99, respectively are achieved by the method. The optimal feature set includes only 5 features (also all from VAT), which might suggest that thoracic VAT plays a more important role than SAT in predicting PGD in lung transplant recipients.

N-acetylcysteine Counteracts Adipose Tissue Macrophage Infiltration and Insulin Resistance Elicited by Advanced Glycated Albumin in Healthy Rats.

PubMed

da Silva, Karolline S; Pinto, Paula R; Fabre, Nelly T; Gomes, Diego J; Thieme, Karina; Okuda, Ligia S; Iborra, Rodrigo T; Freitas, Vanessa G; Shimizu, Maria H M; Teodoro, Walcy R; Marie, Suely K N; Woods, Tom; Brimble, Margaret A; Pickford, Russell; Rye, Kerry-Anne; Okamoto, Maristela; Catanozi, Sergio; Correa-Giannela, Maria L; Machado, Ubiratan F; Passarelli, Marisa

2017-01-01

Background: Advanced glycation endproducts elicit inflammation. However, their role in adipocyte macrophage infiltration and in the development of insulin resistance, especially in the absence of the deleterious biochemical pathways that coexist in diabetes mellitus, remains unknown. We investigated the effect of chronic administration of advanced glycated albumin (AGE-albumin) in healthy rats, associated or not with N-acetylcysteine (NAC) treatment, on insulin sensitivity, adipose tissue transcriptome and macrophage infiltration and polarization. Methods: Male Wistar rats were intraperitoneally injected with control (C) or AGE-albumin alone, or, together with NAC in the drinking water. Biochemical parameters, lipid peroxidation, gene expression and protein contents were, respectively, determined by enzymatic techniques, reactive thiobarbituric acid substances, RT-qPCR and immunohistochemistry or immunoblot. Carboxymethyllysine (CML) and pyrraline (PYR) were determined by LC/mass spectrometry (LC-MS/MS) and ELISA. Results: CML and PYR were higher in AGE-albumin as compared to C. Food consumption, body weight, systolic blood pressure, plasma lipids, glucose, hepatic and renal function, adipose tissue relative weight and adipocyte number were similar among groups. In AGE-treated animals, insulin resistance, adipose macrophage infiltration and Col12a1 mRNA were increased with no changes in M1 and M2 phenotypes as compared to C-albumin-treated rats. Total GLUT4 content was reduced by AGE-albumin as compared to C-albumin. NAC improved insulin sensitivity, reduced urine TBARS, adipose macrophage number and Itgam and Mrc mRNA and increased Slc2a4 and Ppara . CD11b, CD206, Ager, Ddost, Cd36, Nfkb1, Il6, Tnf , Adipoq, Retn, Arg, and Il12 expressions were similar among groups. Conclusions: AGE-albumin sensitizes adipose tissue to inflammation due to macrophage infiltration and reduces GLUT4, contributing to insulin resistance in healthy rats. NAC antagonizes AGE-albumin and prevents insulin resistance. Therefore, it may be a useful tool in the prevention of AGE action on insulin resistance and long-term complications of DM.

Body frame size in school children is related to the amount of adipose tissue in different depots but not to adipose distribution.

PubMed

Guzmán-de la Garza, Francisco J; González Ayala, Alejandra E; Gómez Nava, Marisol; Martínez Monsiváis, Leislie I; Salinas Martínez, Ana M; Ramírez López, Erik; Mathiew Quirós, Alvaro; Garcia Quintanilla, Francisco

2017-09-10

The main aim of this study was to test the hypothesis that body frame size is related to the amount of fat in different adipose tissue depots and to fat distribution in schoolchildren. Children aged between 5 and 10 years were included in this cross-sectional study (n = 565). Body frame size, adiposity markers (anthropometric, skinfolds thickness, and ultrasound measures), and fat distribution indices were analyzed. Correlation coefficients adjusted by reliability were estimated and analyzed by sex; the significance of the difference between two correlation coefficients was assessed using the Fisher z-transformation. The sample included primarily urban children; 58.6% were normal weight, 16.1% overweight, 19.6% obese, and the rest were underweight. Markers of subcutaneous adiposity, fat mass and fat-free mass, and preperitoneal adiposity showed higher and significant correlations with the sum of the biacromial + bitrochanteric diameter than with the elbow diameter, regardless of sex. The fat distribution conicity index presented significant but weak correlations; and visceral adipose tissue, hepatic steatosis, and the waist-for-hip ratio were not significantly correlated with body frame size measures. Body frame size in school children was related to the amount of adipose tissue in different depots, but not adipose distribution. More studies are needed to confirm this relationship and its importance to predict changes in visceral fat deposition during growth. © 2017 Wiley Periodicals, Inc.

Pharmacological evaluation of the mechanisms involved in increased adiposity in zebrafish triggered by the environmental contaminant tributyltin.

PubMed

Ouadah-Boussouf, Nafia; Babin, Patrick J

2016-03-01

One proposed contributing factor to the rise in overweight and obesity is exposure to endocrine disrupting chemicals. Tributyltin chloride (TBT), an organotin, induces adipogenesis in cell culture models and may increases adipose mass in vivo in vertebrate model organisms. It has been hypothesized that TBT acts via the peroxisome proliferator activated receptor (PPAR)γ-dependent pathway. However, the mechanisms involved in the effects of TBT exposure on in vivo adipose tissue metabolism remain unexplored. Semitransparent zebrafish larvae, with their well-developed white adipose tissue, offer a unique opportunity for studying the effects of toxicant chemicals and pharmaceuticals on adipocyte biology and whole-organism adiposity in a vertebrate model. Within hours, zebrafish larvae, treated at environmentally-relevant nanomolar concentrations of TBT, exhibited a remarkable increase in adiposity linked to adipocyte hypertrophy. Under the experimental conditions used, we also demonstrated that zebrafish larvae adipose tissue proved to be highly responsive to selected human nuclear receptor agonists and antagonists. Retinoid X receptor (RXR) homodimers and RXR/liver X receptor heterodimers were suggested to be in vivo effectors of the obesogenic effect of TBT on zebrafish white adipose tissue. RXR/PPARγ heterodimers may be recruited to modulate adiposity in zebrafish but were not a necessary requirement for the short term in vivo TBT obesogenic effect. Together, the present results suggest that TBT may induce the promotion of triacylglycerol storage in adipocytes via RXR-dependent pathways without necessary using PPAR isoforms. Copyright © 2016 Elsevier Inc. All rights reserved.

Lipopolysaccharide-binding protein is a negative regulator of adipose tissue browning in mice and humans.

PubMed

Gavaldà-Navarro, Aleix; Moreno-Navarrete, José M; Quesada-López, Tania; Cairó, Montserrat; Giralt, Marta; Fernández-Real, José M; Villarroya, Francesc

2016-10-01

Adipocyte lipopolysaccharide-binding protein (LBP) biosynthesis is associated with obesity-induced adipose tissue dysfunction. Our purpose was to study the role of LBP in regulating the browning of adipose tissue. Adult mice were maintained at 4°C for 3 weeks or treated with the β3-adrenergic agonist, CL316,243, for 1 week to induce the browning of white fat. Precursor cells from brown and white adipose tissues were cultured under differentiation-inducing conditions to yield brown and beige/brite adipocytes, respectively. In vitro, Lbp was knocked down in 3T3-L1 adipocytes, and cells were treated with recombinant LBP or co-cultured in transwells with control 3T3-L1 adipocytes. Wild-type and Lbp-null mice, fed a standard or high fat diet (HFD) for 15 weeks, were also used in investigations. In humans, subcutaneous and visceral adipose tissue samples were obtained from a cohort of morbidly obese participants. The induction of white fat browning by exposure of mice to cold or CL316,243 treatment was strongly associated with decreased Lbp mRNA expression in white adipose tissue. The acquisition of the beige/brite phenotype in cultured cells was associated with downregulation of Lbp. Moreover, silencing of Lbp induced the expression of brown fat-related genes in adipocytes, whereas LBP treatment reversed this effect. Lbp-null mice exhibited the spontaneous induction of subcutaneous adipose tissue browning, as evidenced by a remarkable increase in Ucp1 and Dio2 gene expression and the appearance of multivacuolar adipocyte clusters. The amount of brown adipose tissue, and brown adipose tissue activity were also increased in Lbp-null mice. These changes were associated with decreased weight gain in Lbp-null mice and protection against HFD-induced inflammatory responses, as shown by reduced IL-6 levels. However, rather than improving glucose homeostasis, these effects led to glucose intolerance and insulin resistance. LBP is identified as a negative regulator of the browning process, which is likely to contribute to the obesity-promoting action of LBP. The deleterious metabolic effects of LBP deletion are compatible with the concept that the appropriate regulation of inflammatory pathways is necessary for a healthy systemic metabolic profile, regardless of body weight regulation.

The role of brown adipose tissue in temperature regulation. [of hibernating and hypothermic mammals

NASA Technical Reports Server (NTRS)

Smith, R. E.

1973-01-01

The thermogenetic capacities of brown adipose tissue were studied on marmots, rats and monkeys in response to cold exposure. All experiments indicated that the brown fat produced heat and slowed the cooling of tissues.

Homeobox a5 Promotes White Adipose Tissue Browning Through Inhibition of the Tenascin C/Toll-Like Receptor 4/Nuclear Factor Kappa B Inflammatory Signaling in Mice.

PubMed

Cao, Weina; Huang, Hongtao; Xia, Tianyu; Liu, Chenlong; Muhammad, Saeed; Sun, Chao

2018-01-01

Lipopolysaccharide (LPS) induces rapid increase in systemic inflammatory factors. As adipose tissue is a key contributor to the inflammatory response to numerous metabolic stimuli, it is important to understand the mechanism behind the LPS-induced inflammation in white adipose tissue (WAT). Homeobox a5 (Hoxa5) is an important transcription factor, which is highly expressed in adipose tissue, and its mRNA expression is increased at cold exposure in mice. So far, the function of Hoxa5 in adipose tissue browning has been poorly understood. So, the objective of this study was conducted to determine the role of Hoxa5 in adipose inflammatory response and white adipose browning in mice. LPS-induced inflammatory and cold-induced browning model were conducted. We compared the coordinated role of Hoxa5 in inflammation and thermogenesis of mice adipose. Transcriptional and methylation regulation was determined by luciferase assay, electrophoretic mobility shift assay, and bisulfite conversion experiment. Hoxa5 and tenascin C (TNC) were involved in WAT inflammation and browning in mice with LPS injection. Furthermore, Hoxa5 inhibited the TNC-involved activation of Toll-like receptor (TLR) 4/nuclear factor kappa B (NF-κB) signal pathway and promoted WAT browning. Moreover, we found that a BMP4/Smad1 signal, closely related to browning, was activated by Hoxa5. Hoxa5 relieved adipocyte inflammation by decreasing TNC-mediated TLR4 transducer and activator of the NF-κB pathway. Interestingly, descended methylation level increased Hoxa5 expression in cold exposure. Our findings demonstrated that Hoxa5 alleviated inflammation and enhanced browning of adipose tissue via negative control of TNC/TLR4/NF-κB inflammatory signaling and activating BMP4/Smad1 pathway. These findings indicated a novel potential means for the regulation of inflammation in adipocytes to prevent obesity and other inflammatory diseases.

[Distributions of H3K27me3 and its modification enzymes in different tissues of mice].

PubMed

Wang, Yuying; Wang, Xinli; Zhang, Ran; Zhang, Zhiyan; Wang, Yu; Yang, Bo; Wang, Guanjie; Zhang, Xin; Ma, Fuhao; Xu, Hongye; Wu, Xiaohui; Zhang, Feng; Li, Qing

2017-11-01

Objective To investigate the levels of trimethylated histone 3 at lysine residue 27 (H3K27me3) and its modification enzymes Zeste gene enhancer homolog 2 (EZH2), lysine-specific demethylase 6B (Kdm6B/JMJD3) and lysine-specific demethylase 6A (Kdm6A/UTX) in tissues and organs of 7-day and 2-month postnatal mice. Methods Immunohistochemistry was used to detect the expressions of H3K27me3 and its modification enzymes EZH2, JMJD3 and UTX in the brain, salivary glands, back fat, thymus, lung, heart, stomach, intestines, liver, testes, and skin of 7-day and 2-month mice. Real-time quantitative PCR was used to confirm the results. The relationships between H3K27me3 and its modification enzymes were analyzed statistically. Results Immunohistochemistry showed H3K27me3 persistently present in all examined tissues of 7-day and 2-month mice. EZH2 was persistently expressed in the brain, heart, liver, and skin of 7-day and 2-month mice, but only expressed in the salivary glands, adipose tissues, thymus, lung, intestines, and testes of 2-month mice. JMJD3 was expressed in the brain, salivary glands, adipose tissues, lung, heart, stomach, intestines, testes, skin of 7-day mice, but was not expressed in the lung, adipose tissues and stomach of 2-month mice. UTX was expressed in the brain, salivary glands, adipose tissues, lung, heart, testes, skin of 7-day mice, but only expressed in the testes of 2-month mice. Most mRNA of H3K27 modification enzymes were moderately or highly expressed as their immunohistochemical results were positive. Conclusion There was H3K27me3 persistently present in the all examined tissues at different stages. EZH2 was mostly expressed in the brain, salivary glands, adipose tissues, thymus, lung, heart, intestines, liver, testes and skin of 2-month-old mice. JMJD3 and UTX were mostly expressed in the brain, salivary glands, adipose tissues, lung, heart, skin and testes of 7-day-old mice. No significant association was found between the distribution of H3K27me3 and the expression of EZH2. There was also no obvious inverse distribution relationship between H3K27me3 and JMJD3 or UTX. Moreover, there was no negative relationship between the distribution of EZH2, JMJD3 and UTX. These results suggest that EZH2, JMJD3 and UTX may play important roles in many tissues of mice after birth. The levels of H3K27me3 and its modified enzymes may be controlled by multiple factors in vivo to fulfill complex physiological functions.

Excess Visceral Adipose Tissue Worsens the Vascular Endothelial Function in Patients with Type 2 Diabetes Mellitus.

PubMed

Kurozumi, Akira; Okada, Yosuke; Arao, Tadashi; Tanaka, Yoshiya

Objective Visceral fat obesity and metabolic syndrome correlate with atherosclerosis in part due to insulin resistance and various other factors. The aim of this study was to determine the relationship between vascular endothelial dysfunction and excess visceral adipose tissue (VAT) in Japanese patients with type 2 diabetes mellitus (T2DM). Methods In 71 T2DM patients, the reactive hyperemia index (RHI) was measured using an Endo-PAT 2000, and VAT and subcutaneous adipose tissue (SAT) were measured via CT. We also measured various metabolic markers, including high-molecular-weight adiponectin (HMW-AN). Results VAT correlated negatively with the natural logarithm of RHI (L_RHI), the primary endpoint (p=0.042, r=-0.242). L_RHI did not correlate with SAT, VAT/SAT, abdominal circumference, homeostasis model assessment for insulin resistance, urinary C-peptide reactivity, HMW-AN, or alanine amino transferase, the secondary endpoints. A linear multivariate analysis via the forced entry method using age, sex, VAT, and smoking history as independent variables and L_RHI as the dependent variable revealed a lack of any determinants of L_RHI. Conclusion Excess VAT worsens the vascular endothelial function, represented by RHI which was analyzed using Endo-PAT, in Japanese patients with T2DM.

SU-E-J-219: A Dixon Based Pseudo-CT Generation Method for MR-Only Radiotherapy Treatment Planning of the Pelvis and Head and Neck

DOE Office of Scientific and Technical Information (OSTI.GOV)

Maspero, M.; Meijer, G.J.; Lagendijk, J.J.W.

2015-06-15

Purpose: To develop an image processing method for MRI-based generation of electron density maps, known as pseudo-CT (pCT), without usage of model- or atlas-based segmentation, and to evaluate the method in the pelvic and head-neck region against CT. Methods: CT and MRI scans were obtained from the pelvic region of four patients in supine position using a flat table top only for CT. Stratified CT maps were generated by classifying each voxel based on HU ranges into one of four classes: air, adipose tissue, soft tissue or bone.A hierarchical region-selective algorithm, based on automatic thresholding and clustering, was used tomore » classify tissues from MR Dixon reconstructed fat, In-Phase (IP) and Opposed-Phase (OP) images. First, a body mask was obtained by thresholding the IP image. Subsequently, an automatic threshold on the Dixon fat image differentiated soft and adipose tissue. K-means clustering on IP and OP images resulted in a mask that, via a connected neighborhood analysis, allowing the user to select the components corresponding to bone structures.The pCT was estimated through assignment of bulk HU to the tissue classes. Bone-only Digital Reconstructed Radiographs (DRR) were generated as well. The pCT images were rigidly registered to the stratified CT to allow a volumetric and voxelwise comparison. Moreover, pCTs were also calculated within the head-neck region in two volunteers using the same pipeline. Results: The volumetric comparison resulted in differences <1% for each tissue class. A voxelwise comparison showed a good classification, ranging from 64% to 98%. The primary misclassified classes were adipose/soft tissue and bone/soft tissue. As the patients have been imaged on different table tops, part of the misclassification error can be explained by misregistration. Conclusion: The proposed approach does not rely on an anatomy model providing the flexibility to successfully generate the pCT in two different body sites. This research is founded by ZonMw IMDI Programme, project name: “RASOR sharp: MRI based radiotherapy planning using a single MRI sequence”, project number: 10-104003010.« less

Metabolic characteristics of human subcutaneous abdominal adipose tissueafter overnight fast

PubMed Central

Humphreys, Sandy M.

2012-01-01

Subcutaneous abdominal adipose tissue is one of the largest fat depots and contributes the major proportion of circulating nonesterified fatty acids (NEFA). Little is known about aspects of human adipose tissue metabolism in vivo other than lipolysis. Here we collated data from 331 experiments in 255 healthy volunteers over a 23-year period, in which subcutaneous abdominal adipose tissue metabolism was studied by measurements of arterio-venous differences after an overnight fast. NEFA and glycerol were released in a ratio of 2.7:1, different (P < 0.001) from the value of 3.0 that would indicate no fatty acid re-esterification. Fatty acid re-esterification was 10.2 ± 1.4%. Extraction of triacylglycerol (TG) (fractional extraction 5.7 ± 0.4%) indicated intravascular lipolysis by lipoprotein lipase, and this contributed 21 ± 3% of the glycerol released. Glucose uptake (fractional extraction 2.6 ± 0.3%) was partitioned around 20–25% for provision of glycerol 3-phosphate and 30% into lactate production. There was release of lactate and pyruvate, with extraction of the ketone bodies 3-hydroxybutyrate and acetoacetate, although these were small numerically compared with TG and glucose uptake. NEFA release (expressed per 100 g tissue) correlated inversely with measures of fat mass (e.g., with BMI, rs = −0.24, P < 0.001). We examined within-person variability. Systemic NEFA concentrations, NEFA release, fatty acid re-esterification, and adipose tissue blood flow were all more consistent within than between individuals. This picture of human adipose tissue metabolism in the fasted state should contribute to a greater understanding of adipose tissue physiology and pathophysiology. PMID:22167523

Rectification of impaired adipose tissue methylation status and lipolytic response contributes to hepatoprotective effect of betaine in a mouse model of alcoholic liver disease

PubMed Central

Dou, Xiaobing; Xia, Yongliang; Chen, Jing; Qian, Ying; Li, Songtao; Zhang, Ximei; Song, Zhenyuan

2014-01-01

Background and Purpose Overactive lipolysis in adipose tissue contributes to the pathogenesis of alcoholic liver disease (ALD); however, the mechanisms involved have not been elucidated. We previously reported that chronic alcohol consumption produces a hypomethylation state in adipose tissue. In this study we investigated the role of hypomethylation in adipose tissue in alcohol-induced lipolysis and whether its correction contributes to the well-established hepatoprotective effect of betaine in ALD. Experimental Approach Male C57BL/6 mice were divided into four groups and started on one of four treatments for 5 weeks: isocaloric pair-fed (PF), alcohol-fed (AF), PF supplemented with betaine (BT/AF) and AF supplemented with betaine (BT/AF). Betaine, 0.5% (w v−1), was added to the liquid diet. Both primary adipocytes and mature 3T3-L1 adipocytes were exposed to demethylation reagents and their lipolytic responses determined. Key Results Betaine alleviated alcohol-induced pathological changes in the liver and rectified the impaired methylation status in adipose tissue, concomitant with attenuating lipolysis. In adipocytes, inducing hypomethylation activated lipolysis through a mechanism involving suppression of protein phosphatase 2A (PP2A), due to hypomethylation of its catalytic subunit, leading to increased activation of hormone-sensitive lipase (HSL). In line with in vitro observations, reduced PP2A catalytic subunit methylation and activity, and enhanced HSL activation, were observed in adipose tissue of alcohol-fed mice. Betaine attenuated this alcohol-induced PP2A suppression and HSL activation. Conclusions and Implications In adipose tissue, a hypomethylation state contributes to its alcohol-induced dysfunction and an improvement in its function may contribute to the hepatoprotective effects of betaine in ALD. PMID:24819676

Start of insulin therapy in patients with type 2 diabetes mellitus promotes the influx of macrophages into subcutaneous adipose tissue.

PubMed

Jansen, H J; Stienstra, R; van Diepen, J A; Hijmans, A; van der Laak, J A; Vervoort, G M M; Tack, C J

2013-12-01

Insulin therapy in patients with type 2 diabetes mellitus is accompanied by weight gain characterised by an increase in abdominal fat mass. The expansion of adipose tissue mass is generally paralleled by profound morphological and inflammatory changes. We hypothesised that the insulin-associated increase in fat mass would also result in changes in the morphology of human subcutaneous adipose tissue and in increased inflammation, especially when weight gain was excessive. We investigated the effects of weight gain on adipocyte size, macrophage influx, and mRNA expression and protein levels of key inflammatory markers within the adipose tissue in patients with type 2 diabetes mellitus before and 6 months after starting insulin therapy. As expected, insulin therapy significantly increased body weight. At the level of the subcutaneous adipose tissue, insulin treatment led to an influx of macrophages. When comparing patients gaining no or little weight with patients gaining >4% body weight after 6 months of insulin therapy, both subgroups displayed an increase in macrophage influx. However, individuals who had gained weight had higher protein levels of monocyte chemoattractant protein-1, TNF-α and IL-1β after 6 months of insulin therapy compared with those who had not gained weight. We conclude that insulin therapy in patients with type 2 diabetes mellitus improved glycaemic control but also induced body weight gain and an influx of macrophages into the subcutaneous adipose tissue. In patients characterised by a pronounced insulin-associated weight gain, the influx of macrophages into the adipose tissue was accompanied by a more pronounced inflammatory status. ClinicalTrials.gov: NCT00781495. The study was funded by European Foundation for the Study of Diabetes and the Dutch Diabetes Research Foundation.

PPAR γ is highly expressed in F4/80hi adipose tissue macrophages and dampens adipose-tissue inflammation

PubMed Central

Bassaganya-Riera, Josep; Misyak, Sarah; Guri, Amir J.; Hontecillas, Raquel

2009-01-01

Macrophage infiltration into adipose tissue is a hallmark of obesity. We recently reported two phenotypically distinct subsets of adipose tissue macrophages (ATM) based on the surface expression of the glycoprotein F4/80 and responsiveness to treatment with a peroxisome proliferator-activated receptor (PPAR) γ agonist. Hence, we hypothesized that F4/80hi and F4/80lo ATM differentially express PPAR γ. This study phenotypically and functionally characterizes F4/80hi and F4/80lo ATM subsets during obesity. Changes in gene expression were also examined on sorted F4/80lo and F4/80hi ATM by quantitative real-time RT-PCR. We show that while F4/80lo macrophages predominate in adipose tissue of lean mice, obesity causes accumulation of both F4/80lo and F4/80hi ATM. Moreover, accumulation of F4/80hi ATM in adipose tissue is associated with impaired glucose tolerance. Phenotypically, F4/80hi ATM express greater amounts of CD11c, MHC II, CD49b, and CX3CR1 and produce more TNF-α, MCP-1, and IL-10 than F4/80lo ATM. Gene expression analyses of the sorted populations revealed that only the F4/80lo population produced IL-4, whereas the F4/80hi ATM expressed greater amounts of PPAR γ, δ, CD36 and toll-like receptor-4. In addition, the deficiency of PPAR γ in immune cells favors expression of M1 and impairs M2 macrophage marker expression in adipose tissue. Thus, PPAR γ is differentially expressed in F4/80hi versus F4/80low ATM subsets and its deficiency favors a predominance of M1 markers in WAT. PMID:19423085

Inflammation and Fibrosis in Perirenal Adipose Tissue of Patients With Aldosterone-Producing Adenoma.

PubMed

Wu, Chunyan; Zhang, Huijian; Zhang, Jiajun; Xie, Cuihua; Fan, Cunxia; Zhang, Hongbin; Wu, Peng; Wei, Qiang; Tan, Wanlong; Xu, Lingling; Wang, Ling; Xue, Yaoming; Guan, Meiping

2018-01-01

The prevalence of primary aldosteronism is much higher than previously thought. Recent studies have shown that primary aldosteronism is related to a higher risk of cardiovascular events. However, the underlying mechanism is not yet clear. Here we investigate the characteristics, including inflammation, fibrosis, and adipokine expression, of adipose tissues from different deposits in patients with aldosterone-producing adenoma (APA). Inflammation and fibrosis changes were evaluated in perirenal and subcutaneous adipose tissues obtained from patients with APA (n = 16), normotension (NT; n = 10), and essential hypertension (EH; n = 5) undergoing laparoscopic surgery. We also evaluated the effect of aldosterone in isolated human perirenal adipose tissue stromal vascular fraction (SVF) cells and investigated the effect of aldosterone in mouse 3T3-L1 and brown preadipocytes. Compared with the EH group, significantly higher levels of interleukin-6 (IL-6) and tumor necrosis factor-α messenger RNA (mRNA) and protein were observed in perirenal adipose tissue of patients with APA. Expression of genes related to fibrosis and adipogenesis in perirenal adipose tissue was notably higher in patients with APA than in patients with NT and EH. Aldosterone significantly induced IL-6 and fibrosis gene mRNA expression in differentiated SVF cells. Aldosterone treatment enhanced mRNA expression of genes associated with inflammation and fibrosis and stimulated differentiation of 3T3-L1 and brown preadipocytes. In conclusion, these data indicate that high aldosterone in patients with APA may induce perirenal adipose tissue dysfunction and lead to inflammation and fibrosis, which may be involved in the high risk of cardiovascular events observed in patients with primary aldosteronism. Copyright © 2018 Endocrine Society.

Genetic regulation of adipose tissue transcript expression is involved in modulating serum triglyceride and HDL-cholesterol.

PubMed

Sajuthi, Satria P; Sharma, Neeraj K; Comeau, Mary E; Chou, Jeff W; Bowden, Donald W; Freedman, Barry I; Langefeld, Carl D; Parks, John S; Das, Swapan K

2017-10-20

Dyslipidemia is a major contributor to the increased cardiovascular disease and mortality associated with obesity and type 2 diabetes. We hypothesized that variation in expression of adipose tissue transcripts is associated with serum lipid concentrations in African Americans (AAs), and common genetic variants regulate expression levels of these transcripts. Fasting serum lipid levels, genome-wide transcript expression profiles of subcutaneous adipose tissue, and genome-wide SNP genotypes were analyzed in a cohort of non-diabetic AAs (N=250). Serum triglyceride (TRIG) and high density lipoprotein-cholesterol (HDL-C) levels were associated (FDR<0.01) with expression level of 1021 and 1875 adipose tissue transcripts, respectively, but none associated with total cholesterol or LDL-C levels. Serum HDL-C-associated transcripts were enriched for salient biological pathways, including branched-chain amino acid degradation, and oxidative phosphorylation. Genes in immuno-inflammatory pathways were activated among individuals with higher serum TRIG levels. We identified significant cis-regulatory SNPs (cis-eSNPs) for 449 serum lipid-associated transcripts in adipose tissue. The cis-eSNPs of 12 genes were nominally associated (p<0.001) with serum lipid level in genome wide association studies in Global Lipids Genetics Consortium (GLGC) cohorts. Allelic effect direction of cis-eSNPs on expression of MARCH2, BEST1 and TMEM258 matched with effect direction of these SNP alleles on serum TRIG or HDL-C levels in GLGC cohorts. These data suggest that expressions of serum lipid-associated transcripts in adipose tissue are dependent on common cis-eSNPs in African Americans. Thus, genetically-mediated transcriptional regulation in adipose tissue may play a role in reducing HDL-C and increasing TRIG in serum. Copyright © 2017 Elsevier B.V. All rights reserved.

Amyloid Precursor Protein and Proinflammatory Changes Are Regulated in Brain and Adipose Tissue in a Murine Model of High Fat Diet-Induced Obesity

PubMed Central

Puig, Kendra L.; Floden, Angela M.; Adhikari, Ramchandra; Golovko, Mikhail Y.; Combs, Colin K.

2012-01-01

Background Middle age obesity is recognized as a risk factor for Alzheimer's disease (AD) although a mechanistic linkage remains unclear. Based upon the fact that obese adipose tissue and AD brains are both areas of proinflammatory change, a possible common event is chronic inflammation. Since an autosomal dominant form of AD is associated with mutations in the gene coding for the ubiquitously expressed transmembrane protein, amyloid precursor protein (APP) and recent evidence demonstrates increased APP levels in adipose tissue during obesity it is feasible that APP serves some function in both disease conditions. Methodology/Principal Findings To determine whether diet-induced obesity produced proinflammatory changes and altered APP expression in brain versus adipose tissue, 6 week old C57BL6/J mice were maintained on a control or high fat diet for 22 weeks. Protein levels and cell-specific APP expression along with markers of inflammation and immune cell activation were compared between hippocampus, abdominal subcutaneous fat and visceral pericardial fat. APP stimulation-dependent changes in macrophage and adipocyte culture phenotype were examined for comparison to the in vivo changes. Conclusions/Significance Adipose tissue and brain from high fat diet fed animals demonstrated increased TNF-α and microglial and macrophage activation. Both brains and adipose tissue also had elevated APP levels localizing to neurons and macrophage/adipocytes, respectively. APP agonist antibody stimulation of macrophage cultures increased specific cytokine secretion with no obvious effects on adipocyte culture phenotype. These data support the hypothesis that high fat diet-dependent obesity results in concomitant pro-inflammatory changes in brain and adipose tissue that is characterized, in part, by increased levels of APP that may be contributing specifically to inflammatory changes that occur. PMID:22276186

The role of Ad-36 as a risk factor in males with gynecomastia.

PubMed

Kocazeybek, Bekir; Saribas, Suat; Ergin, Sevgi

2015-12-01

Gynecomastia is highly prevalent worldwide and Adenovirus-36 (Ad-36), recently implicated in increased adipose tissue deposition due to its affinity for adipose tissue, is a potential etiological agent in the development of obesity and therefore we hypothesized that Ad-36 may also play a role in the development of gynecomastia by possibly accompanying increased regional adiposity. To support our hypothesis, we conducted a study that included 33 adult males with gynecomastia (PG) and 15 adult males as the patient control group (HCG). Leptin and adiponectin levels were monitored using ELISA. A significant difference in Ad-36 antibody positivity was found between the groups (p<0.05). Average leptin levels were found to be higher, but average adiponectin levels were found to be lower in Ad-36 Ab(+) patient group. No Ad-36 DNA was detected in any tissue samples. In conclusion, we hypothesize that low-grade chronic inflammation, which was caused by Ad-36 infection, possibly caused an increase in circulating leptin. This in turn may have caused an increase in local or circulating estrogens and/or the estrogen/androgen ratio by stimulating the aromatase enzyme activity in adipose stromal cells and breast tissues. We suggest that gynecomastia may develop following an increase in aromatase enzyme activity, by which more oestrogen is produced and the estrogen-androgen balance disrupted. Also, regional adipose tissue enlargements may cause the excessive production of estrogens leading to gynecomastia. Adipose tissue has been recognized as a major endocrine organ in recent years. Another plausible explanation is excessive aromatization of androgens to estrogens by peripheral adipose tissue may promote gynecomastia in males. Moreover, our results suggest that there might be a relationship between Ad-36 and gynecomastia. Copyright © 2015 Elsevier Ltd. All rights reserved.

Insulin resistance, hepatic lipid and adipose tissue distribution in HIV-infected men.

PubMed

He, Qing; Engelson, Ellen S; Ionescu, Gabriel; Glesby, Marshall J; Albu, Jeanine B; Kotler, Donald P

2008-01-01

A large proportion of HIV-infected patients on antiretroviral medication develop insulin resistance, especially in the context of fat redistribution. This study investigates the interrelationships among fat distribution, hepatic lipid content, and insulin resistance in HIV-infected men. We performed a cross-sectional analysis of baseline data from 23 HIV-infected participants in three prospective clinical studies. Magnetic resonance spectroscopy was used to quantify hepatic lipid concentrations. Magnetic resonance imaging was used to quantify whole-body adipose tissue compartments: that is, subcutaneous adipose tissue (SAT) and visceral adipose tissue (VAT) volumes, as well as the intermuscular adipose tissue (IMAT) subcompartment and the omental-mesenteric adipose tissue (OMAT) and retroperitoneal adipose tissue (RPAT) subcompartments of VAT. The homeostasis model for assessment of insulin resistance (HOMA-IR) was calculated from fasting glucose and insulin concentrations. Hepatic lipid content correlated significantly with total VAT (r = 0.62, P = 0.0014), but not with SAT (r = 0.053, P = 0.81). In univariate analysis, hepatic lipid content was associated with the OMAT (r = 0.67, P = 0.0004) and RPAT (r = 0.53, P = 0.009) subcompartments; HOMA-IR correlated with both VAT and hepatic lipid contents (r = 0.61, P = 0.057 and r = 0.68, P = 0.0012, respectively). In stepwise linear regression models, hepatic lipid had the strongest associations with OMAT and with HOMA-IR. Hepatic lipid content is associated with VAT volume, especially the OMAT subcompartment, in HIV-infected men. Hepatic lipid content is associated with insulin resistance in HIV-infected men. Hepatic lipid content might mediate the relationship between VAT and insulin resistance among treated, HIV-infected men.

Dietary overload lithium decreases the adipogenesis in abdominal adipose tissue of broiler chickens.

PubMed

Bai, Shiping; Pan, Shuqin; Zhang, Keying; Ding, Xuemei; Wang, Jianping; Zeng, Qiufeng; Xuan, Yue; Su, Zuowei

2017-01-01

To investigate the toxic effects of dietary overload lithium on the adipogenesis in adipose tissue of chicken and the role of hypothalamic neuropeptide Y (NPY) in this process, one-day-old male chicks were fed with the basal diet added with 0 (control) or 100mg lithium/kg diet from lithium chloride (overload lithium) for 35days. Abdominal adipose tissue and hypothalamus were collected at day 6, 14, and 35. As a percentage of body weight, abdominal fat decreased (p<0.001) at day 6, 14, and 35, and feed intake and body weight gain decreased during day 7-14, and day 15-35 in overload lithium treated broilers as compared to control. Adipocyte diameter and DNA content in abdominal adipose tissue were significantly lower in overload-lithium treatment than control at day 35, although no significant differences were observed at day 6 and 14. Dietary overload lithium decreased (p<0.01) transcriptional expression of preadipocyte proliferation makers ki-67 (KI67), microtubule-associated protein homolog (TPX2), and topoisomerase 2-alpha (TOP2A), and preadipocyte differentiation transcriptional factors peroxisome proliferator-activated receptor-γ (PPARγ), and CCAAT/enhancer binding protein (C/EBP) α mRNA abundance in abdominal adipose tissue. In hypothalamus, dietary overload lithium influenced (p<0.001) NPY, and NPY receptor (NPYR) 6 mRNA abundance at day 6 and 14, but not at day 35. In conclusion, dietary overload lithium decreased the adipogenesis in abdominal adipose tissue of chicken, which was accompanied by depressing transcriptional expression of adipogenesis-associated factors. Hypothalamic NPY had a potential role in the adipogenesis in abdominal adipose tissue of broilers with a short-term overload lithium treatment. Copyright © 2016 Elsevier B.V. All rights reserved.

PPAR gamma is highly expressed in F4/80(hi) adipose tissue macrophages and dampens adipose-tissue inflammation.

PubMed

Bassaganya-Riera, Josep; Misyak, Sarah; Guri, Amir J; Hontecillas, Raquel

2009-01-01

Macrophage infiltration into adipose tissue is a hallmark of obesity. We recently reported two phenotypically distinct subsets of adipose tissue macrophages (ATM) based on the surface expression of the glycoprotein F4/80 and responsiveness to treatment with a peroxisome proliferator-activated receptor (PPAR) gamma agonist. Hence, we hypothesized that F4/80(hi) and F4/80(lo) ATM differentially express PPAR gamma. This study phenotypically and functionally characterizes F4/80(hi) and F4/80(lo) ATM subsets during obesity. Changes in gene expression were also examined on sorted F4/80(lo) and F4/80(hi) ATM by quantitative real-time RT-PCR. We show that while F4/80(lo) macrophages predominate in adipose tissue of lean mice, obesity causes accumulation of both F4/80(lo) and F4/80(hi) ATM. Moreover, accumulation of F4/80(hi) ATM in adipose tissue is associated with impaired glucose tolerance. Phenotypically, F4/80(hi) ATM express greater amounts of CD11c, MHC II, CD49b, and CX3CR1 and produce more TNF-alpha, MCP-1, and IL-10 than F4/80(lo) ATM. Gene expression analyses of the sorted populations revealed that only the F4/80(lo) population produced IL-4, whereas the F4/80(hi) ATM expressed greater amounts of PPAR gamma, delta, CD36 and toll-like receptor-4. In addition, the deficiency of PPAR gamma in immune cells favors expression of M1 and impairs M2 macrophage marker expression in adipose tissue. Thus, PPAR gamma is differentially expressed in F4/80(hi) versus F4/80(low) ATM subsets and its deficiency favors a predominance of M1 markers in WAT.

Handheld Tissue Hardness Meters for Assessing the Mechanical Properties of Skeletal Muscle: A Feasibility Study.

PubMed

Chino, Kentaro; Takahashi, Hideyuki

2016-09-01

The purpose of this study was to examine the feasibility of using handheld tissue hardness meters to assess the mechanical properties of skeletal muscle. This observational study included 33 healthy men (age, 22.4 ± 4.4 years) and 33 healthy women (age, 23.7 ± 4.2 years). Participants were placed in a supine position, and tissue hardness overlying the rectus femoris and the shear modulus of the muscle were measured on the right side of the body at 50% thigh length. In the same position, subcutaneous adipose tissue thickness and muscle thickness were measured using B-mode ultrasonography. To examine the associations of subcutaneous adipose tissue thickness, muscle thickness, and muscle shear modulus with tissue hardness, linear regression using a stepwise bidirectional elimination approach was performed. Stepwise linear regression revealed that subcutaneous adipose tissue thickness (r = -0.38, P = .002) and muscle shear modulus (r = 0.27, P = .03) were significantly associated with tissue hardness. Significant associations among adipose tissue thickness, muscle shear modulus, and tissue hardness show the limitations and feasibility of handheld tissue hardness meters for assessing the mechanical properties of skeletal muscles. Copyright © 2016. Published by Elsevier Inc.

Purification and differentiation of human adipose-derived stem cells by membrane filtration and membrane migration methods

PubMed Central

Lin, Hong Reng; Heish, Chao-Wen; Liu, Cheng-Hui; Muduli, Saradaprasan; Li, Hsing-Fen; Higuchi, Akon; Kumar, S. Suresh; Alarfaj, Abdullah A.; Munusamy, Murugan A.; Hsu, Shih-Tien; Chen, Da-Chung; Benelli, Giovanni; Murugan, Kadarkarai; Cheng, Nai-Chen; Wang, Han-Chow; Wu, Gwo-Jang

2017-01-01

Human adipose-derived stem cells (hADSCs) are easily isolated from fat tissue without ethical concerns, but differ in purity, pluripotency, differentiation ability, and stem cell marker expression, depending on the isolation method. We isolated hADSCs from a primary fat tissue solution using: (1) conventional culture, (2) a membrane filtration method, (3) a membrane migration method where the primary cell solution was permeated through membranes, adhered hADSCs were cultured, and hADSCs migrated out from the membranes. Expression of mesenchymal stem cell markers and pluripotency genes, and osteogenic differentiation were compared for hADSCs isolated by different methods using nylon mesh filter membranes with pore sizes ranging from 11 to 80 μm. hADSCs isolated by the membrane migration method had the highest MSC surface marker expression and efficient differentiation into osteoblasts. Osteogenic differentiation ability of hADSCs and MSC surface marker expression were correlated, but osteogenic differentiation ability and pluripotent gene expression were not. PMID:28071738

Characteristics, changes and influence of body composition during a 4486 km transcontinental ultramarathon: results from the Transeurope Footrace mobile whole body MRI-project

PubMed Central

2013-01-01

Background Almost nothing is known about the medical aspects of runners doing a transcontinental ultramarathon over several weeks. The results of differentiated measurements of changes in body composition during the Transeurope Footrace 2009 using a mobile whole body magnetic resonance (MR) imager are presented and the proposed influence of visceral and somatic adipose and lean tissue distribution on performance tested. Methods 22 participants were randomly selected for the repeated MR measurements (intervals: 800 km) with a 1.5 Tesla MR scanner mounted on a mobile unit during the 64-stage 4,486 km ultramarathon. A standardized and validated MRI protocol was used: T1 weighted turbo spin echo sequence, echo time 12 ms, repetition time 490 ms, slice thickness 10 mm, slice distance 10 mm (breath holding examinations). For topographic tissue segmentation and mapping a modified fuzzy c-means algorithm was used. A semi-automatic post-processing of whole body MRI data sets allows reliable analysis of the following body tissue compartments: Total body volume (TV), total somatic (TSV) and total visceral volume (TVV), total adipose (TAT) and total lean tissue (TLT), somatic (SLT) and visceral lean tissue (VLT), somatic (SAT) and visceral adipose tissue (VAT) and somatic adipose soft tissue (SAST). Specific volume changes were tested on significance. Tests on difference and relationship regarding prerace and race performance and non-finishing were done using statistical software SPSS. Results Total, somatic and visceral volumes showed a significant decrease throughout the race. Adipose tissue showed a significant decrease compared to the start at all measurement times for TAT, SAST and VAT. Lean adipose tissues decreased until the end of the race, but not significantly. The mean relative volume changes of the different tissue compartments at the last measurement compared to the start were: TV −9.5% (SE 1.5%), TSV −9.4% (SE 1.5%), TVV −10.0% (SE 1.4%), TAT −41.3% (SE 2.3%), SAST −48.7% (SE 2.8%), VAT −64.5% (SE 4.6%), intraabdominal adipose tissue (IAAT) −67.3% (SE 4.3%), mediastinal adopose tissue (MAT) −41.5% (SE 7.1%), TLT −1.2% (SE 1.0%), SLT −1.4% (SE 1.1%). Before the start and during the early phase of the Transeurope Footrace 2009, the non-finisher group had a significantly higher percentage volume of TVV, TAT, SAST and VAT compared to the finisher group. VAT correlates significantly with prerace training volume and intensity one year before the race and with 50 km- and 24 hour-race records. Neither prerace body composition nor specific tissue compartment volume changes showed a significant relationship to performance in the last two thirds of the Transeurope Footrace 2009. Conclusions With this mobile MRI field study the complex changes in body composition during a multistage ultramarathon could be demonstrated in detail in a new and differentiated way. Participants lost more than half of their adipose tissue. Even lean tissue volume (mainly skeletal muscle tissue) decreased due to the unpreventable chronic negative energy balance during the race. VAT has the fastest and highest decrease compared to SAST and lean tissue compartments during the race. It seems to be the most sensitive morphometric parameter regarding the risk of non-finishing a transcontinental footrace and shows a direct relationship to prerace-performance. However, body volume or body mass and, therefore, fat volume has no correlation with total race performances of ultra-athletes finishing a 4,500 km multistage race. PMID:23657091

Impaired Local Production of Proresolving Lipid Mediators in Obesity and 17-HDHA as a Potential Treatment for Obesity-Associated Inflammation

PubMed Central

Neuhofer, Angelika; Zeyda, Maximilian; Mascher, Daniel; Itariu, Bianca K.; Murano, Incoronata; Leitner, Lukas; Hochbrugger, Eva E.; Fraisl, Peter; Cinti, Saverio; Serhan, Charles N.; Stulnig, Thomas M.

2013-01-01

Obesity-induced chronic low-grade inflammation originates from adipose tissue and is crucial for obesity-driven metabolic deterioration, including insulin resistance and type 2 diabetes. Chronic inflammation may be a consequence of a failure to actively resolve inflammation and could result from a lack of local specialized proresolving lipid mediators (SPMs), such as resolvins and protectins, which derive from the n-3 polyunsaturated fatty acids eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA). We assessed obesity-induced changes of n-3–derived SPMs in adipose tissue and the effects of dietary EPA/DHA thereon. Moreover, we treated obese mice with SPM precursors and investigated the effects on inflammation and metabolic dysregulation. Obesity significantly decreased DHA-derived 17-hydroxydocosahexaenoic acid (17-HDHA, resolvin D1 precursor) and protectin D1 (PD1) levels in murine adipose tissue. Dietary EPA/DHA treatment restored endogenous biosynthesis of n-3–derived lipid mediators in obesity while attenuating adipose tissue inflammation and improving insulin sensitivity. Notably, 17-HDHA treatment reduced adipose tissue expression of inflammatory cytokines, increased adiponectin expression, and improved glucose tolerance parallel to insulin sensitivity in obese mice. These findings indicate that impaired biosynthesis of certain SPM and SPM precursors, including 17-HDHA and PD1, contributes to adipose tissue inflammation in obesity and suggest 17-HDHA as a novel treatment option for obesity-associated complications. PMID:23349501

Impaired local production of proresolving lipid mediators in obesity and 17-HDHA as a potential treatment for obesity-associated inflammation.

PubMed

Neuhofer, Angelika; Zeyda, Maximilian; Mascher, Daniel; Itariu, Bianca K; Murano, Incoronata; Leitner, Lukas; Hochbrugger, Eva E; Fraisl, Peter; Cinti, Saverio; Serhan, Charles N; Stulnig, Thomas M

2013-06-01

Obesity-induced chronic low-grade inflammation originates from adipose tissue and is crucial for obesity-driven metabolic deterioration, including insulin resistance and type 2 diabetes. Chronic inflammation may be a consequence of a failure to actively resolve inflammation and could result from a lack of local specialized proresolving lipid mediators (SPMs), such as resolvins and protectins, which derive from the n-3 polyunsaturated fatty acids eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA). We assessed obesity-induced changes of n-3-derived SPMs in adipose tissue and the effects of dietary EPA/DHA thereon. Moreover, we treated obese mice with SPM precursors and investigated the effects on inflammation and metabolic dysregulation. Obesity significantly decreased DHA-derived 17-hydroxydocosahexaenoic acid (17-HDHA, resolvin D1 precursor) and protectin D1 (PD1) levels in murine adipose tissue. Dietary EPA/DHA treatment restored endogenous biosynthesis of n-3-derived lipid mediators in obesity while attenuating adipose tissue inflammation and improving insulin sensitivity. Notably, 17-HDHA treatment reduced adipose tissue expression of inflammatory cytokines, increased adiponectin expression, and improved glucose tolerance parallel to insulin sensitivity in obese mice. These findings indicate that impaired biosynthesis of certain SPM and SPM precursors, including 17-HDHA and PD1, contributes to adipose tissue inflammation in obesity and suggest 17-HDHA as a novel treatment option for obesity-associated complications.

Fatty acid signatures of stomach oil and adipose tissue of northern fulmars (Fulmarus glacialis) in Alaska: Implications for diet analysis of Procellariiform birds

USGS Publications Warehouse

Wang, S.W.; Iverson, S.J.; Springer, A.M.; Hatch, Shyla A.

2007-01-01

Procellariiforms are unique among seabirds in storing dietary lipids in both adipose tissue and stomach oil. Thus, both lipid sources are potentially useful for trophic studies using fatty acid (FA) signatures. However, little is known about the relationship between FA signatures in stomach oil and adipose tissue of individuals or whether these signatures provide similar information about diet and physiology. We compared the FA composition of stomach oil and adipose tissue biopsies of individual northern fulmars (N = 101) breeding at three major colonies in Alaska. Fatty acid signatures differed significantly between the two lipid sources, reflecting differences in dietary time scales, metabolic processing, or both. However, these signatures exhibited a relatively consistent relationship between individuals, such that the two lipid sources provided a similar ability to distinguish foraging differences among individuals and colonies. Our results, including the exclusive presence of dietary wax esters in stomach oil but not adipose tissue, are consistent with the notion that stomach oil FA signatures represent lipids retained from prey consumed during recent foraging and reflect little metabolic processing, whereas adipose tissue FA signatures represent a longer-term integration of dietary intake. Our study illustrates the potential for elucidating short- versus longer-term diet information in Procellariiform birds using different lipid sources. ?? 2007 Springer-Verlag.

Adipocyte fetuin-A contributes to macrophage migration into adipose tissue and polarization of macrophages.

PubMed

Chatterjee, Priyajit; Seal, Soma; Mukherjee, Sandip; Kundu, Rakesh; Mukherjee, Sutapa; Ray, Sukanta; Mukhopadhyay, Satinath; Majumdar, Subeer S; Bhattacharya, Samir

2013-09-27

Macrophage infiltration into adipose tissue during obesity and their phenotypic conversion from anti-inflammatory M2 to proinflammatory M1 subtype significantly contributes to develop a link between inflammation and insulin resistance; signaling molecule(s) for these events, however, remains poorly understood. We demonstrate here that excess lipid in the adipose tissue environment may trigger one such signal. Adipose tissue from obese diabetic db/db mice, high fat diet-fed mice, and obese diabetic patients showed significantly elevated fetuin-A (FetA) levels in respect to their controls; partially hepatectomized high fat diet mice did not show noticeable alteration, indicating adipose tissue to be the source of this alteration. In adipocytes, fatty acid induces FetA gene and protein expressions, resulting in its copious release. We found that FetA could act as a chemoattractant for macrophages. To simulate lipid-induced inflammatory conditions when proinflammatory adipose tissue and macrophages create a niche of an altered microenvironment, we set up a transculture system of macrophages and adipocytes; the addition of fatty acid to adipocytes released FetA into the medium, which polarized M2 macrophages to M1. This was further confirmed by direct FetA addition to macrophages. Taken together, lipid-induced FetA from adipocytes is an efficient chemokine for macrophage migration and polarization. These findings open a new dimension for understanding obesity-induced inflammation.

Metformin increases the novel adipokine adipolin/CTRP12: role of the AMPK pathway.

PubMed

Tan, Bee K; Chen, Jing; Adya, Raghu; Ramanjaneya, Manjunath; Patel, Vanlata; Randeva, Harpal S

2013-11-01

Adipolin is a novel adipokine with anti-inflammatory and glucose-lowering properties. Lower levels of adipolin are found in obese and diabetic mice. Polycystic ovary syndrome (PCOS) is a pro-inflammatory state associated with obesity and diabetes. To date, there are no human studies on adipolin. Therefore, we measured serum (ELISA) and adipose tissue adipolin mRNA expression (RT-PCR) and protein concentrations (western blotting) in PCOS and control subjects. We also investigated the ex vivo effect of glucose and metformin on adipolin protein production in human subcutaneous adipose tissue explants. We report novel data that serum and subcutaneous adipose tissue adipolin mRNA expression and protein concentrations were significantly lower in women with PCOS compared with control subjects. Furthermore, Spearman's rank analysis showed that serum adipolin concentrations were significantly negatively correlated with BMI, waist-to-hip ratio, and glucose (P<0.05). However, when subjected to multiple regression analysis, none of these variables were predictive of serum adipolin concentrations (P>0.05). Also, subcutaneous adipose tissue adipolin mRNA expression and protein concentrations were only significantly negatively correlated with glucose (P<0.05). No significant correlations were found with omental adipose tissue adipolin mRNA expression and protein concentrations (P>0.05). Moreover, glucose profoundly reduced and metformin significantly increased adipolin protein production in human adipose tissue explants respectively. Importantly, metformin's effects appear to be via the AMP-activated protein kinase signaling pathway.

Allele Compensation in Tip60+/− Mice Rescues White Adipose Tissue Function In Vivo

PubMed Central

Gao, Yuan; Hamers, Nicole; Rakhshandehroo, Maryam; Berger, Ruud; Lough, John; Kalkhoven, Eric

2014-01-01

Adipose tissue is a key regulator of energy homestasis. The amount of adipose tissue is largely determined by adipocyte differentiation (adipogenesis), a process that is regulated by the concerted actions of multiple transcription factors and cofactors. Based on in vitro studies in murine 3T3-L1 preadipocytes and human primary preadipocytes, the transcriptional cofactor and acetyltransferase Tip60 was recently identified as an essential adipogenic factor. We therefore investigated the role of Tip60 on adipocyte differentiation and function, and possible consequences on energy homeostasis, in vivo. Because homozygous inactivation results in early embryonic lethality, Tip60+/− mice were used. Heterozygous inactivation of Tip60 had no effect on body weight, despite slightly higher food intake by Tip60+/− mice. No major effects of heterozygous inactivation of Tip60 were observed on adipose tissue and liver, and Tip60+/− displayed normal glucose tolerance, both on a low fat and a high fat diet. While Tip60 mRNA was reduced to 50% in adipose tissue, the protein levels were unaltered, suggesting compensation by the intact allele. These findings indicate that the in vivo role of Tip60 in adipocyte differentiation and function cannot be properly addressed in Tip60+/− mice, but requires the generation of adipose tissue-specific knock out animals or specific knock-in mice. PMID:24870614

Glucose uptake and glycolytic flux in adipose tissue from rats adapted to a high-protein, carbohydrate-free diet.

PubMed

Brito, S R; Moura, M A; Kawashita, N H; Brito, M N; Kettelhut, I C; Migliorini, R H

2001-10-01

Rates of glucose uptake by epididymal and retroperitoneal adipose tissue in vivo, as well as rates of hexose uptake and glycolytic flux in isolated adipocytes, were determined in rats adapted to a high-protein, carbohydrate-free (HP) diet and in control rats fed a balanced (N) diet. Adaptation to the HP diet induced a significant reduction in rates of glucose uptake, estimated with 2-deoxy-[1-(3)H]-glucose, both by adipose tissue (epididymal and retroperitoneal) in vivo and by isolated adipocytes. Twelve hours after replacement of the HP diet with the balanced diet, rates of adipose tissue uptake in vivo in HP-adapted rats returned to levels that did not differ significantly from those in N-fed rats. The rate of flux in the glycolytic pathway, estimated with (3)H[5]-glucose, was also significantly reduced in adipocytes from HP-fed rats. In agreement with the above findings, the activities of hexokinase (HK), phosphofructo-1-kinase (PFK-1), and pyruvate kinase (PK) were markedly reduced in adipose tissue from HP-adapted rats. The activity of pyruvate kinase was partially reverted by diet replacement for 12 hours. The low-plasma insulin and high-glucagon levels in HP-fed rats may have played an important role in the reduction of adipose tissue glucose utilization in these animals. Copyright 2001 by W.B. Saunders Company

Adipose Tissues Characteristics of Normal, Obesity, and Type 2 Diabetes in Uygurs Population

PubMed Central

Zhang, Jun; Zhang, Zhiwei; Ding, Yulei; Xu, Peng; Wang, Tingting; Xu, Wenjing; Lu, Huan; Li, Jun; Wang, Yan; Li, Siyuan; Liu, Zongzhi; An, Na; Yang, Li; Xie, Jianxin

2015-01-01

Our results showed that, at the same BMI level, Uygurs have greater WHR values, abdominal visceral fat content, and diabetes risks than Kazaks. In addition, values of HDL-C in Uygur subjects were lower than those in Kazak subjects, and values of creatinine, uric acid, diastolic blood pressure, blood glucose, and fructosamine in Uygur male subjects were lower than those in Kazak male subjects. In contrast, systolic blood pressure values in Uygur subjects were greater than those in Kazak subjects, and blood glucose values were greater in Uygur female subjects than in Kazak female subjects. Additionally, in Uygurs, visceral adipose tissue expression levels of TBX1 and TCF21 were greater in obesity group than in normal and T2DM groups and lower in T2DM group than in normal group (P < 0.01). The visceral adipose tissue expression levels of APN in normal group was greater than those in obesity and T2DM groups, and visceral adipose tissue expression levels of TNF-α and MCP-1 in normal group were lower than those in obesity and T2DM groups (P < 0.01). In conclusion, T2DM in Uygurs was mainly associated with not only distribution of adipose tissue in body, but also change in metabolic activity and adipocytokines secretion of adipose tissue. PMID:26273678

Dietary Quercetin Attenuates Adipose Tissue Expansion and Inflammation and Alters Adipocyte Morphology in a Tissue-Specific Manner

PubMed Central

Forney, Laura A.; Lenard, Natalie R.; Stewart, Laura K.

2018-01-01

Chronic inflammation in adipose tissue may contribute to depot-specific adipose tissue expansion, leading to obesity and insulin resistance. Dietary supplementation with quercetin or botanical extracts containing quercetin attenuates high fat diet (HFD)-induced obesity and insulin resistance and decreases inflammation. Here, we determined the effects of quercetin and red onion extract (ROE) containing quercetin on subcutaneous (inguinal, IWAT) vs. visceral (epididymal, EWAT) white adipose tissue morphology and inflammation in mice fed low fat, high fat, high fat plus 50 μg/day quercetin or high fat plus ROE containing 50 μg/day quercetin equivalents for 9 weeks. Quercetin and ROE similarly ameliorated HFD-induced increases in adipocyte size and decreases in adipocyte number in IWAT and EWAT. Furthermore, quercetin and ROE induced alterations in adipocyte morphology in IWAT. Quercetin and ROE similarly decreased HFD-induced IWAT inflammation. However, quercetin and red onion differentially affected HFD-induced EWAT inflammation, with quercetin decreasing and REO increasing inflammatory marker gene expression. Quercetin and REO also differentially regulated circulating adipokine levels. These results show that quercetin or botanical extracts containing quercetin induce white adipose tissue remodeling which may occur through inflammatory-related mechanisms. PMID:29562620

Altered vocal fold kinematics in synthetic self-oscillating models that employ adipose tissue as a lateral boundary condition.

NASA Astrophysics Data System (ADS)

Saidi, Hiba; Erath, Byron D.

2015-11-01

The vocal folds play a major role in human communication by initiating voiced sound production. During voiced speech, the vocal folds are set into sustained vibrations. Synthetic self-oscillating vocal fold models are regularly employed to gain insight into flow-structure interactions governing the phonation process. Commonly, a fixed boundary condition is applied to the lateral, anterior, and posterior sides of the synthetic vocal fold models. However, physiological observations reveal the presence of adipose tissue on the lateral surface between the thyroid cartilage and the vocal folds. The goal of this study is to investigate the influence of including this substrate layer of adipose tissue on the dynamics of phonation. For a more realistic representation of the human vocal folds, synthetic multi-layer vocal fold models have been fabricated and tested while including a soft lateral layer representative of adipose tissue. Phonation parameters have been collected and are compared to those of the standard vocal fold models. Results show that vocal fold kinematics are affected by adding the adipose tissue layer as a new boundary condition.

An increase in epicardial fat in women is associated with thrombotic risk.

PubMed

Basurto Acevedo, Lourdes; Barrera Hernández, Susana; Fernández Muñoz, María de Jesús; Saucedo García, Renata Patricia; Rodríguez Luna, Ana Karen; Martínez Murillo, Carlos

2018-01-29

A decrease in fibrinolytic activity and an increase in the thickness of the epicardial adipose tissue have been observed in patients with coronary artery disease. The aim of this study was to determine the association between epicardial adipose tissue and fibrinolytic activity by measuring the concentration of plasminogen activator inhibitor-1 (PAI-1). A cross-sectional study was conducted on 56 apparently healthy women aged 45 to 60 years. Anthropometric measurements and biochemical determinations were performed on all participants. The fibrinolytic activity was determined by measuring PAI-1 by ELISA. Epicardial thickness was assessed by transthoracic echocardiography. The concentration of PAI-1 was directly associated with the thickness of the epicardial adipose tissue (r=0.475, P=.001), body mass index (BMI), visceral adipose tissue, insulin resistance, glucose, and HDL-cholesterol. The multivariate regression analysis indicated that epicardial fat independently predicts the concentrations of PAI-1. Women with thicker epicardial adipose tissue have reduced fibrinolytic activity, and consequently greater thrombotic risk. Copyright © 2017 Sociedad Española de Arteriosclerosis. Publicado por Elsevier España, S.L.U. All rights reserved.

Angiogenic Deficiency and Adipose Tissue Dysfunction Are Associated with Macrophage Malfunction in SIRT1−/− Mice

PubMed Central

Xu, Fen; Burk, David; Gao, Zhanguo; Yin, Jun; Zhang, Xia

2012-01-01

The histone deacetylase sirtuin 1 (SIRT1) inhibits adipocyte differentiation and suppresses inflammation by targeting the transcription factors peroxisome proliferator-activated receptor γ and nuclear factor κB. Although this suggests that adiposity and inflammation should be enhanced when SIRT1 activity is inactivated in the body, this hypothesis has not been tested in SIRT1 null (SIRT1−/−) mice. In this study, we addressed this issue by investigating the adipose tissue in SIRT1−/− mice. Compared with their wild-type littermates, SIRT1 null mice exhibited a significant reduction in body weight. In adipose tissue, the average size of adipocytes was smaller, the content of extracellular matrix was lower, adiponectin and leptin were expressed at 60% of normal level, and adipocyte differentiation was reduced. All of these changes were observed with a 50% reduction in capillary density that was determined using a three-dimensional imaging technique. Except for vascular endothelial growth factor, the expression of several angiogenic factors (Pdgf, Hgf, endothelin, apelin, and Tgf-β) was reduced by about 50%. Macrophage infiltration and inflammatory cytokine expression were 70% less in the adipose tissue of null mice and macrophage differentiation was significantly inhibited in SIRT1−/− mouse embryonic fibroblasts in vitro. In wild-type mice, macrophage deletion led to a reduction in vascular density. These data suggest that SIRT1 controls adipose tissue function through regulation of angiogenesis, whose deficiency is associated with macrophage malfunction in SIRT1−/− mice. The study supports the concept that inflammation regulates angiogenesis in the adipose tissue. PMID:22315447

Olanzapine promotes fat accumulation in male rats by decreasing physical activity, repartitioning energy and increasing adipose tissue lipogenesis while impairing lipolysis.

PubMed

Albaugh, V L; Judson, J G; She, P; Lang, C H; Maresca, K P; Joyal, J L; Lynch, C J

2011-05-01

Olanzapine and other atypical antipsychotics cause metabolic side effects leading to obesity and diabetes; although these continue to be an important public health concern, their underlying mechanisms remain elusive. Therefore, an animal model of these side effects was developed in male Sprague-Dawley rats. Chronic administration of olanzapine elevated fasting glucose, impaired glucose and insulin tolerance, increased fat mass but, in contrast to female rats, did not increase body weight or food intake. Acute studies were conducted to delineate the mechanisms responsible for these effects. Olanzapine markedly decreased physical activity without a compensatory decline in food intake. It also acutely elevated fasting glucose and worsened oral glucose and insulin tolerance, suggesting that these effects are adiposity independent. Hyperinsulinemic-euglycemic clamp studies measuring (14)C-2-deoxyglucose uptake revealed tissue-specific insulin resistance. Insulin sensitivity was impaired in skeletal muscle, but either unchanged or increased in adipose tissue depots. Consistent with the olanzapine-induced hyperglycemia, there was a tendency for increased (14)C-2-deoxyglucose uptake into fat depots of fed rats and, surprisingly, free fatty acid (FFA) uptake into fat depots was elevated approximately twofold. The increased glucose and FFA uptake into adipose tissue was coupled with increased adipose tissue lipogenesis. Finally, olanzapine lowered fasting plasma FFA, and as it had no effect on isoproterenol-stimulated rises in plasma glucose, it blunted isoproterenol-stimulated in vivo lipolysis in fed rats. Collectively, these results suggest that olanzapine exerts several metabolic effects that together favor increased accumulation of fuel into adipose tissue, thereby increasing adiposity.

Adipose Tissue Responses to Breaking Sitting in Men and Women with Central Adiposity.

PubMed

Chen, Yung-Chih; Betts, James A; Walhin, Jean-Philippe; Thompson, Dylan

2018-04-27

Breaking prolonged sitting reduces postprandial glucose and insulin concentrations and influences skeletal muscle molecular signalling pathways but it is unknown whether breaking sitting also affects adipose tissue. Eleven central overweight participants (7 men and 4 post-menopausal women) aged 50 ± 5 years (means ± SD) completed two mixed-meal feeding trials (PROLONGED SITTING versus BREAKING SITTING) in a randomised, counterbalanced design. The BREAKING SITTING intervention comprised walking for 2 min every 20 min over 5.5 h. Blood samples were taken at regular intervals to examine metabolic biomarkers and adipokine concentrations. Adipose tissue samples were taken at baseline and at 5.5 h to examine changes in mRNA expression and secretion of selected adipokines ex-vivo. Postprandial glycaemia and insulinaemia were attenuated by approximately 50% and 40% in BREAKING SITTING compared to PROLONGED SITTING (iAUC: 359 ± 117 versus 697 ± 218 mmol·330 min·L, p = 0.001 and 202 ± 71 versus 346 ± 150 nmol·330 min·L, p = 0.001, respectively). Despite these pronounced and sustained differences in postprandial glucose and insulin concentrations, adipose tissue mRNA expression for various genes (IL-6, leptin, adiponectin, PDK4, IRS1/2, PI3K and Akt1, etc.) and ex-vivo adipose tissue secretion of IL-6, leptin and adiponectin were not different between trials. This study demonstrates that breaking sitting with short bouts of physical activity has very pronounced effects on systemic postprandial glucose and insulin concentrations but this does not translate into corresponding effects within adipose tissue.

Sex and depot differences in ex vivo adipose tissue fatty acid storage and glycerol-3-phosphate acyltransferase activity

PubMed Central

Morgan-Bathke, Maria; Chen, Liang; Oberschneider, Elisabeth; Harteneck, Debra

2015-01-01

Adipose tissue fatty acid storage varies according to sex, adipose tissue depot, and degree of fat gain. However, the mechanism(s) for these variations is not completely understood. We examined whether differences in adipose tissue glycerol-3-phosphate acyltransferase (GPAT) might play a role in these variations. We optimized an enzyme activity assay for total GPAT and GPAT1 activity in human adipose tissue and measured GPAT activity. Omental and subcutaneous adipose tissue was collected from obese and nonobese adults for measures of GPAT and GPAT1 activities, ex vivo palmitate storage, acyl-CoA synthetase (ACS) and diacylglycerol-acyltransferase (DGAT) activities, and CD36 protein. Total GPAT and GPAT1 activities decreased as a function of adipocyte size in both omental (r = −0.71, P = 0.003) and subcutaneous (r = −0.58, P = 0.04) fat. The relative contribution of GPAT1 to total GPAT activity increased as a function of adipocyte size, accounting for up to 60% of GPAT activity in those with the largest adipocytes. We found strong, positive correlations between ACS, GPAT, and DGAT activities for both sexes and depots (r values 0.58–0.91) and between these storage factors and palmitate storage rates into TAG (r values 0.55–0.90). We conclude that: 1) total GPAT activity decreases as a function of adipocyte size; 2) GPAT1 can account for over half of adipose GPAT activity in hypertrophic obesity; and 3) ACS, GPAT, and DGAT are coordinately regulated. PMID:25738782

[Human brown adipose tissue].

PubMed

Virtanen, Kirsi A; Nuutila, Pirjo

2015-01-01

Adult humans have heat-producing and energy-consuming brown adipose tissue in the clavicular region of the neck. There are two types of brown adipose cells, the so-called classic and beige adipose cells. Brown adipose cells produce heat by means of uncoupler protein 1 (UCP1) from fatty acids and sugar. By applying positron emission tomography (PET) measuring the utilization of sugar, the metabolism of brown fat has been shown to multiply in the cold, presumably influencing energy consumption. Active brown fat is most likely present in young adults, persons of normal weight and women, least likely in obese persons.

MR signal-fat-fraction analysis and T2* weighted imaging measure BAT reliably on humans without cold exposure.

PubMed

Holstila, Milja; Pesola, Marko; Saari, Teemu; Koskensalo, Kalle; Raiko, Juho; Borra, Ronald J H; Nuutila, Pirjo; Parkkola, Riitta; Virtanen, Kirsi A

2017-05-01

Brown adipose tissue (BAT) is compositionally distinct from white adipose tissue (WAT) in terms of triglyceride and water content. In adult humans, the most significant BAT depot is localized in the supraclavicular area. Our aim is to differentiate brown adipose tissue from white adipose tissue using fat T2* relaxation time mapping and signal-fat-fraction (SFF) analysis based on a commercially available modified 2-point-Dixon (mDixon) water-fat separation method. We hypothesize that magnetic resonance (MR) imaging can reliably measure BAT regardless of the cold-induced metabolic activation, with BAT having a significantly higher water and iron content compared to WAT. The supraclavicular area of 13 volunteers was studied on 3T PET-MRI scanner using T2* relaxation time and SFF mapping both during cold exposure and at ambient temperature; and 18 F-FDG PET during cold exposure. Volumes of interest (VOIs) were defined semiautomatically in the supraclavicular fat depot, subcutaneous WAT and muscle. The supraclavicular fat depot (assumed to contain BAT) had a significantly lower SFF and fat T2* relaxation time compared to subcutaneous WAT. Cold exposure did not significantly affect MR-based measurements. SFF and T2* values measured during cold exposure and at ambient temperature correlated inversely with the glucose uptake measured by 18 F-FDG PET. Human BAT can be reliably and safely assessed using MRI without cold activation and PET-related radiation exposure. Copyright © 2017 Elsevier Inc. All rights reserved.

Comparison of fractionation strategies for offline two-dimensional liquid chromatography tandem mass spectrometry analysis of proteins from mouse adipose tissue.

PubMed

Sajic, Tatjana; Varesio, Emmanuel; Szanto, Ildiko; Hopfgartner, Gérard

2015-09-01

In the frame of protein identification from mouse adipose tissue, two strategies were compared for the offline elution of peptides from a strong cation exchange (SCX) column in two-dimensional liquid chromatography tandem mass spectrometry (2D-LC-MS/MS) analyses. First, the salt gradient (using K(+) as displacing agent) was evaluated from 25 to 500mM KCl. Then, a less investigated elution mode using a pH gradient (using citric acid and ammonium hydroxide) was carried out from pH 2.5 to 9.0. Equal amounts of peptide digest derived from mouse adipose tissue were loaded onto the SCX column and fractionated according to the two approaches. A total of 15 fractions were collected in two independent experiments for each SCX elution strategy. Then, each fraction was analyzed on a nanoLC-MS/MS platform equipped with a column-switching unit for desalting and enrichment. No substantial differences in peptide quality characteristics (molecular weight, isoelectric point, or GRAVY [grand average of hydropathicity] index distributions) were observed between the two datasets. The pH gradient approach was found to be superior, with 27.5% more unique peptide identifications and 10% more distinct protein identifications compared with the salt-based elution method. In conclusion, our data imply that the pH gradient SCX fractionation is more desirable for proteomics analysis of entire adipose tissue. Copyright © 2015 Elsevier Inc. All rights reserved.

Insulin Mediated 14C-Glucose Incorporation Into Adipose Tissue: An Undergraduate Biochemistry Experiment

ERIC Educational Resources Information Center

Landman, A. D.; Eskin, N. A. M.

1975-01-01

Describes an experiment in which rat adipose tissue samples are exposed to labeled glucose; insulin is added to one sample. Subsequent scintillation counting demonstrates the ability of insulin to facilitate the entry of glucose into the tissue. (MLH)

Whole- and refined-grain intakes are differentially associated with abdominal visceral and subcutaneous adiposity in healthy adults: The Framingham Heart Study

USDA-ARS?s Scientific Manuscript database

Different aspects of diet may be differentially related to body fat distribution. The purpose of this study was to assess associations between whole- and refined- grain intake and abdominal subcutaneous adipose tissue (SAT) and visceral adipose tissue (VAT). We examined the cross-sectional associati...

Aging is associated with an increase in T cells and inflammatory macrophages in visceral adipose tissue1

PubMed Central

Lumeng, Carey N.; Liu, Jianhua; Geletka, Lynn; Delaney, Colin; DelProposto, Jennifer; Desai, Anjali; Oatmen, Kelsie; Martinez-Santibanez, Gabriel; Julius, Annabelle; Garg, Sanjay; Yung, Raymond L.

2011-01-01

Age-related adiposity has been linked to chronic inflammatory diseases in late-life. To date, the studies on adipose tissue leukocytes and aging have not taken into account the heterogeneity of adipose tissue macrophages (ATMs), nor have they examined how age impacts other leukocytes such as T cell in fat. Therefore, we have performed a detailed examination of ATM subtypes in young and old mice using state of the art techniques. Our results demonstrate qualitative changes in ATMs with aging that generate a decrease in resident Type 2 (M2) ATMs. The profile of ATMs in old fat shifts towards a pro-inflammatory environment with increased numbers of CD206-CD11c- (double negative) ATMs. The mechanism of this aging-induced shift in the phenotypic profile of ATMs was found to be related to a decrease in PPARγ expression in ATMs and alterations in chemokine/chemokine receptor expression profiles. Furthermore, we have revealed a profound and unexpected expansion of adipose tissue T (ATT) cells in visceral fat with aging that includes a significant induction of regulatory T cells (Tregs) in fat. Our findings demonstrate a unique inflammatory cell signature in the physiologic context of aging adipose tissue that differs from those induced in setting of diet-induced obesity. PMID:22075699

Fat body, fat pad and adipose tissues in invertebrates and vertebrates: the nexus

PubMed Central

2014-01-01

The fat body in invertebrates was shown to participate in energy storage and homeostasis, apart from its other roles in immune mediation and protein synthesis to mention a few. Thus, sharing similar characteristics with the liver and adipose tissues in vertebrates. However, vertebrate adipose tissue or fat has been incriminated in the pathophysiology of metabolic disorders due to its role in production of pro-inflammatory cytokines. This has not been reported in the insect fat body. The link between the fat body and adipose tissue was examined in this review with the aim of determining the principal factors responsible for resistance to inflammation in the insect fat body. This could be the missing link in the prevention of metabolic disorders in vertebrates, occasioned by obesity. PMID:24758278

Adipose Tissue as an Endocrine Organ: An Update on Pro-inflammatory and Anti-inflammatory Microenvironment.

PubMed

Smitka, Kvido; Marešová, Dana

2015-01-01

Adipose tissue is recognized as an active endocrine organ that produces a number of endocrine substances referred to as "adipokines" including leptin, adiponectin, adipolin, visfatin, omentin, tumour necrosis factor-alpha (TNF-α), interleukin-6 (IL-6), resistin, pigment epithelium-derived factor (PEDF), and progranulin (PGRN) which play an important role in the food intake regulation and significantly influence insulin sensitivity and in some cases directly affect insulin resistance in skeletal muscle, liver, and adipose tissue. The review summarizes current knowledge about adipose tissue-derived hormones and their influence on energy homeostasis regulation. The possible therapeutic potential of these adipokines in the treatment of insulin resistance, endothelial dysfunction, a pro-inflammatory response, obesity, eating disorders, progression of atherosclerosis, type 1 diabetes, and type 2 diabetes is discussed.

CCR7 Maintains Nonresolving Lymph Node and Adipose Inflammation in Obesity

PubMed Central

Hellmann, Jason; Sansbury, Brian E.; Holden, Candice R.; Tang, Yunan; Wong, Blenda; Wysoczynski, Marcin; Rodriguez, Jorge; Bhatnagar, Aruni; Hill, Bradford G.

2016-01-01

Accumulation of immune cells in adipose tissue promotes insulin resistance in obesity. Although innate and adaptive immune cells contribute to adipose inflammation, the processes that sustain these interactions are incompletely understood. Here we show that obesity promotes the accumulation of CD11c+ adipose tissue immune cells that express C-C chemokine receptor 7 (CCR7) in mice and humans, and that CCR7 contributes to chronic inflammation and insulin resistance. We identified that CCR7+ macrophages and dendritic cells accumulate in adipose tissue in close proximity to lymph nodes (LNs) (i.e., perinodal) and visceral adipose. Consistent with the role of CCR7 in regulating the migration of immune cells to LNs, obesity promoted the accumulation of CD11c+ cells in LNs, which was prevented by global or hematopoietic deficiency of Ccr7. Obese Ccr7−/− mice had reduced accumulation of CD8+ T cells, B cells, and macrophages in adipose tissue, which was associated with reduced inflammatory signaling. This reduction in maladaptive inflammation translated to increased insulin signaling and improved glucose tolerance in obesity. Therapeutic administration of an anti-CCR7 antibody phenocopied the effects of genetic Ccr7 deficiency in mice with established obesity. These results suggest that CCR7 plays a causal role in maintaining innate and adaptive immunity in obesity. PMID:27207557

PCOS is associated with increased CD11c expression and crown-like structures in adipose tissue and increased central abdominal fat depots independent of obesity.

PubMed

Huang, Zhi Hua; Manickam, Buvana; Ryvkin, Victoria; Zhou, Xiaohong Joe; Fantuzzi, Giamila; Mazzone, Theodore; Sam, Susan

2013-01-01

Adipose tissue macrophage (ATM) infiltration is a major pathway for obesity-induced insulin resistance but has not been studied as a mechanism for insulin resistance in PCOS. We tested whether polycystic ovary syndrome (PCOS) is associated with increased ATM infiltration, especially of inflammatory subtype identified by the CD11c marker. We conducted a case-control study at an academic medical center in the United States. Fourteen PCOS and 14 control women of similar age and body mass index (BMI) underwent a gluteal fat biopsy. Markers of ATM, integrins, TNF-α, and adiponectin, were analyzed by quantitative RT-PCR using a standard curve method. Crown-like structures (CLS) were identified by immunohistochemistry. Abdominal magnetic resonance imaging and frequently sampled i.v. glucose tolerance test were performed to assess abdominal fat and insulin sensitivity (SI). Women with PCOS were compared with control women of similar age and BMI for ATM markers, CLS density, adipose tissue expression of inflammatory cytokines and adiponectin, SI, and abdominal fat depots. Women with PCOS had an increase in CD11c expression (P = 0.03), CLS density (P = 0.001), α5 expression (P = 0.009), borderline increase in TNF-α expression (P = 0.08), and a decrease in adiponectin expression (P = 0.02) in gluteal adipose tissue. Visceral (P = 0.009) and sc abdominal fat (P = 0.005) were increased in PCOS. SI was lower in PCOS (P = 0.008). PCOS is associated with an increase in CD11c expression and CLS density and a decrease in adiponectin expression in sc adipose tissue. Additionally, PCOS is associated with higher central abdominal fat depots independent of BMI. These alterations are present among mostly nonobese women and could represent mechanisms for insulin resistance.

VAT=TAAT-SAAT: innovative anthropometric model to predict visceral adipose tissue without resort to CT-Scan or DXA.

PubMed

Samouda, Hanen; Dutour, Anne; Chaumoitre, Kathia; Panuel, Michel; Dutour, Olivier; Dadoun, Frédéric

2013-01-01

To investigate whether a combination of a selected but limited number of anthropometric measurements predicts visceral adipose tissue (VAT) better than other anthropometric measurements, without resort to medical imaging. Abdominal anthropometric measurements are total abdominal adipose tissue indicators and global measures of VAT and SAAT (subcutaneous abdominal adipose tissue). Therefore, subtracting the anthropometric measurement the more correlated possible with SAAT while being the least correlated possible with VAT, from the most correlated abdominal anthropometric measurement with VAT while being highly correlated with TAAT, may better predict VAT. BMI participants' range was from 16.3 to 52.9 kg m(-2) . Anthropometric and abdominal adipose tissues data by computed tomography (CT-Scan) were available in 253 patients (18-78 years) (CHU Nord, Marseille) and used to develop the anthropometric VAT prediction models. Subtraction of proximal thigh circumference from waist circumference, adjusted to age and/or BMI, predicts better VAT (Women: VAT = 2.15 × Waist C - 3.63 × Proximal Thigh C + 1.46 × Age + 6.22 × BMI - 92.713; R(2) = 0.836. Men: VAT = 6 × Waist C - 4.41 × proximal thigh C + 1.19 × Age - 213.65; R(2) = 0.803) than the best single anthropometric measurement or the association of two anthropometric measurements highly correlated with VAT. Both multivariate models showed no collinearity problem. Selected models demonstrate high sensitivity (97.7% in women, 100% in men). Similar predictive abilities were observed in the validation sample (Women: R(2) = 76%; Men: R(2) = 70%). Bland and Altman method showed no systematic estimation error of VAT. Validated in a large range of age and BMI, our results suggest the usefulness of the anthropometric selected models to predict VAT in Europides (South of France). Copyright © 2013 The Obesity Society.

Magnetic Resonance Imaging Cooling-Reheating Protocol Indicates Decreased Fat Fraction via Lipid Consumption in Suspected Brown Adipose Tissue

PubMed Central

Lundström, Elin; Strand, Robin; Johansson, Lars; Bergsten, Peter; Ahlström, Håkan; Kullberg, Joel

2015-01-01

Objectives To evaluate whether a water-fat magnetic resonance imaging (MRI) cooling-reheating protocol could be used to detect changes in lipid content and perfusion in the main human brown adipose tissue (BAT) depot after a three-hour long mild cold exposure. Materials and Methods Nine volunteers were investigated with chemical-shift-encoded water-fat MRI at baseline, after a three-hour long cold exposure and after subsequent short reheating. Changes in fat fraction (FF) and R2*, related to ambient temperature, were quantified within cervical-supraclavicular adipose tissue (considered as suspected BAT, denoted sBAT) after semi-automatic segmentation. In addition, FF and R2* were quantified fully automatically in subcutaneous adipose tissue (not considered as suspected BAT, denoted SAT) for comparison. By assuming different time scales for the regulation of lipid turnover and perfusion in BAT, the changes were determined as resulting from either altered absolute fat content (lipid-related) or altered absolute water content (perfusion-related). Results sBAT-FF decreased after cold exposure (mean change in percentage points = -1.94 pp, P = 0.021) whereas no change was observed in SAT-FF (mean = 0.23 pp, P = 0.314). sBAT-R2* tended to increase (mean = 0.65 s-1, P = 0.051) and SAT-R2* increased (mean = 0.40 s-1, P = 0.038) after cold exposure. sBAT-FF remained decreased after reheating (mean = -1.92 pp, P = 0.008, compared to baseline) whereas SAT-FF decreased (mean = -0.79 pp, P = 0.008, compared to after cold exposure). Conclusions The sustained low sBAT-FF after reheating suggests lipid consumption, rather than altered perfusion, as the main cause to the decreased sBAT-FF. The results obtained demonstrate the use of the cooling-reheating protocol for detecting changes in the cervical-supraclavicular fat depot, being the main human brown adipose tissue depot, in terms of lipid content and perfusion. PMID:25928226

Infrared thermography, a new method for detection of brown adipose tissue activity after a meal in humans

NASA Astrophysics Data System (ADS)

Habek, Nikola; Kordić, Milan; Jurenec, Franjo; Dugandžić, Aleksandra

2018-03-01

The activation of brown adipose tissue (BAT) after cold exposure leads to heat production. However, the activation of BAT activity after a meal as part of diet induced thermogenesis is still controversial. A possible reason is that measuring BAT activity by positron emission tomography-computed tomography (PET CT) via accumulation of radiotracer fludeoxyglucose (18F-FDG), which competes with an increase in glucose concentration after a meal, fails as the method of choice. In this study, activity of BAT was determined by infrared thermography. Activation of BAT 30 min after a meal increases glucose consumption, decreases plasma glucose concentration, and leads to changes of body temperature (diet-induced thermogenesis). Detecting pathophysiological changes in BAT activity after a meal by infrared thermography, a non-invasive more sensitive method, will be of great importance for people with increased body weight and diabetes mellitus type 2.

Measurement of Basal and Forskolin-stimulated Lipolysis in Inguinal Adipose Fat Pads.

PubMed

Baskaran, Padmamalini; Thyagarajan, Baskaran

2017-07-21

Lipolysis is a process by which the lipid stored as triglycerides in adipose tissues are hydrolyzed into glycerol and fatty acids. This article describes the method for the measurement of basal and forskolin (FSK)-stimulated lipolysis in the inguinal fat pads isolated from wild type mice fed either normal chow diet (NCD), high fat diet (HFD) or a high fat diet containing 0.01% of capsaicin (CAP; transient receptor potential vanilloid subfamily 1 (TRPV1) agonist) for 32 weeks. The method described here for performing ex vivo lipolysis is adopted from Schweiger et al. 1 We present a detailed protocol for measuring glycerol levels by UV-Visible (UV/VIS) spectrophotometry. The method described here can be used to successfully isolate inguinal fat pads for lipolysis measurements to obtain consistent results. The protocol described for inguinal fat pads can readily be extended to measure lipolysis in other tissues.

Carotenoids and their conversion products in the control of adipocyte function, adiposity and obesity.

PubMed

Luisa Bonet, M; Canas, Jose A; Ribot, Joan; Palou, Andreu

2015-04-15

A novel perspective of the function of carotenoids and carotenoid-derived products - including, but not restricted to, the retinoids - is emerging in recent years which connects these compounds to the control of adipocyte biology and body fat accumulation, with implications for the management of obesity, diabetes and cardiovascular disease. Cell and animal studies indicate that carotenoids and carotenoids derivatives can reduce adiposity and impact key aspects of adipose tissue biology including adipocyte differentiation, hypertrophy, capacity for fatty acid oxidation and thermogenesis (including browning of white adipose tissue) and secretory function. Epidemiological studies in humans associate higher dietary intakes and serum levels of carotenoids with decreased adiposity. Specifically designed human intervention studies, though still sparse, indicate a beneficial effect of carotenoid supplementation in the accrual of abdominal adiposity. The objective of this review is to summarize recent findings in this area, place them in physiological contexts, and provide likely regulatory schemes whenever possible. The focus will be on the effects of carotenoids as nutritional regulators of adipose tissue biology and both animal and human studies, which support a role of carotenoids and retinoids in the prevention of abdominal adiposity. Copyright © 2015 The Authors. Published by Elsevier Inc. All rights reserved.

Identification of Novel Tissue-Specific Genes by Analysis of Microarray Databases: A Human and Mouse Model

PubMed Central

Suh, Yeunsu; Davis, Michael E.; Lee, Kichoon

2013-01-01

Understanding the tissue-specific pattern of gene expression is critical in elucidating the molecular mechanisms of tissue development, gene function, and transcriptional regulations of biological processes. Although tissue-specific gene expression information is available in several databases, follow-up strategies to integrate and use these data are limited. The objective of the current study was to identify and evaluate novel tissue-specific genes in human and mouse tissues by performing comparative microarray database analysis and semi-quantitative PCR analysis. We developed a powerful approach to predict tissue-specific genes by analyzing existing microarray data from the NCBI′s Gene Expression Omnibus (GEO) public repository. We investigated and confirmed tissue-specific gene expression in the human and mouse kidney, liver, lung, heart, muscle, and adipose tissue. Applying our novel comparative microarray approach, we confirmed 10 kidney, 11 liver, 11 lung, 11 heart, 8 muscle, and 8 adipose specific genes. The accuracy of this approach was further verified by employing semi-quantitative PCR reaction and by searching for gene function information in existing publications. Three novel tissue-specific genes were discovered by this approach including AMDHD1 (amidohydrolase domain containing 1) in the liver, PRUNE2 (prune homolog 2) in the heart, and ACVR1C (activin A receptor, type IC) in adipose tissue. We further confirmed the tissue-specific expression of these 3 novel genes by real-time PCR. Among them, ACVR1C is adipose tissue-specific and adipocyte-specific in adipose tissue, and can be used as an adipocyte developmental marker. From GEO profiles, we predicted the processes in which AMDHD1 and PRUNE2 may participate. Our approach provides a novel way to identify new sets of tissue-specific genes and to predict functions in which they may be involved. PMID:23741331

Inactivation of adipose angiotensinogen reduces adipose tissue macrophages and increases metabolic activity.

PubMed

LeMieux, Monique J; Ramalingam, Latha; Mynatt, Randall L; Kalupahana, Nishan S; Kim, Jung Han; Moustaïd-Moussa, Naïma

2016-02-01

The adipose renin-angiotensin system (RAS) has been linked to obesity-induced inflammation, though mechanisms are not completely understood. In this study, adipose-specific angiotensinogen knockout mice (Agt-KO) were generated to determine whether Agt inactivation reduces inflammation and alters the metabolic profile of the Agt-KO mice compared to wild-type (WT) littermates. Adipose tissue-specific Agt-KO mice were created using the Cre-LoxP system with both Agt-KO and WT littermates fed either a low-fat or high-fat diet to assess metabolic changes. White adipose tissue was used for gene/protein expression analyses and WAT stromal vascular cells for metabolic extracellular flux assays. No significant differences were observed in body weight or fat mass between both genotypes on either diet. However, improved glucose clearance was observed in Agt-KO compared to WT littermates, consistent with higher expression of genes involved in insulin signaling, glucose transport, and fatty acid metabolism. Furthermore, Agt inactivation reduced total macrophage infiltration in Agt-KO mice fed both diets. Lastly, stroma vascular cells from Agt-KO mice revealed higher metabolic activity compared to WT mice. These findings indicate that adipose-specific Agt inactivation leads to reduced adipose inflammation and increased glucose tolerance mediated in part via increased metabolic activity of adipose cells. © 2015 The Obesity Society.

Aquaglyceroporins serve as metabolic gateways in adiposity and insulin resistance control

PubMed Central

Catalán, Victoria; Gómez-Ambrosi, Javier; Frühbeck, Gema

2011-01-01

Aquaglyceroporins (AQP3, AQP7, AQP9 and AQP10) encompass a subfamily of aquaporins that allow the movement of water and other small solutes, especially glycerol, through cell membranes. Adipose tissue constitutes a major source of glycerol via AQP7. We have recently reported that, in addition to the well-known expression of AQP7 in adipose tissue, AQP3 and AQP9 are also expressed in omental and subcutaneous fat depots. Moreover, insulin and leptin act as regulators of aquaglyceroporins through the PI3K/Akt/mTOR pathway. AQP3 and AQP7 appear to facilitate glycerol efflux from adipose tissue while reducing the glycerol influx into hepatocytes via AQP9 to prevent the excessive lipid accumulation and the subsequent aggravation of hyperglycemia in human obesity. This Extra View focuses on the control of glycerol release by aquaglyceroporins in the adipose tissue and briefly discusses the importance of glycerol as a substrate for hepatic gluconeogenesis, pancreatic insulin secretion and cardiac ATP production. PMID:21502813

Wasabi leaf extracts attenuate adipocyte hypertrophy through PPARγ and AMPK.

PubMed

Oowatari, Yasuo; Ogawa, Tetsuro; Katsube, Takuya; Iinuma, Kiyohisa; Yoshitomi, Hisae; Gao, Ming

2016-08-01

Hypertrophy of adipocytes in obese adipose tissues causes metabolic abnormality by adipocytokine dysregulation, which promotes type 2 diabetes mellitus, hypertension, and dyslipidemia. We investigated the effects of wasabi (Wasabia japonica Matsum) leaf extracts on metabolic abnormalities in SHRSP.Z-Leprfa/IzmDmcr rats (SHRSP/ZF), which are a model of metabolic syndrome. Male SHRSP/ZF rats aged 7 weeks were divided into two groups: control and wasabi leaf extract (WLE) groups, which received water or oral treatment with 4 g/kg/day WLE for 6 weeks. WLE improved the body weight gain and high blood pressure in SHRSP/ZF rats, and the plasma triglyceride levels were significantly lower in the WLE group. Adipocyte hypertrophy was markedly prevented in adipose tissue. The expression of PPARγ and subsequent downstream genes was suppressed in the WLE group adipose tissues. Our data suggest that WLE inhibits adipose hypertrophy by suppressing PPARγ expression in adipose tissue and stimulating the AMPK activity by increased adiponectin.

Characterization of In Vitro Engineered Human Adipose Tissues: Relevant Adipokine Secretion and Impact of TNF-α

PubMed Central

Aubin, Kim; Safoine, Meryem; Proulx, Maryse; Audet-Casgrain, Marie-Alice; Côté, Jean-François; Têtu, Félix-André; Roy, Alphonse; Fradette, Julie

2015-01-01

Representative modelling of human adipose tissue functions is central to metabolic research. Tridimensional models able to recreate human adipogenesis in a physiological tissue-like context in vitro are still scarce. We describe the engineering of white adipose tissues reconstructed from their cultured adipose-derived stromal precursor cells. We hypothesize that these reconstructed tissues can recapitulate key functions of AT under basal and pro-inflammatory conditions. These tissues, featuring human adipocytes surrounded by stroma, were stable and metabolically active in long-term cultures (at least 11 weeks). Secretion of major adipokines and growth factors by the reconstructed tissues was determined and compared to media conditioned by human native fat explants. Interestingly, the secretory profiles of the reconstructed adipose tissues indicated an abundant production of leptin, PAI-1 and angiopoietin-1 proteins, while higher HGF levels were detected for the human fat explants. We next demonstrated the responsiveness of the tissues to the pro-inflammatory stimulus TNF-α, as reflected by modulation of MCP-1, NGF and HGF secretion, while VEGF and leptin protein expression did not vary. TNF-α exposure induced changes in gene expression for adipocyte metabolism-associated mRNAs such as SLC2A4, FASN and LIPE, as well as for genes implicated in NF-κB activation. Finally, this model was customized to feature adipocytes representative of progressive stages of differentiation, thereby allowing investigations using newly differentiated or more mature adipocytes. In conclusion, we produced tridimensional tissues engineered in vitro that are able to recapitulate key characteristics of subcutaneous white adipose tissue. These tissues are produced from human cells and their neo-synthesized matrix elements without exogenous or synthetic biomaterials. Therefore, they represent unique tools to investigate the effects of pharmacologically active products on human stromal cells, extracellular matrix and differentiated adipocytes, in addition to compounds modulating adipogenesis from precursor cells. PMID:26367137

Obesity, Inflammation, and Cancer.

PubMed

Deng, Tuo; Lyon, Christopher J; Bergin, Stephen; Caligiuri, Michael A; Hsueh, Willa A

2016-05-23

Obesity, a worldwide epidemic, confers increased risk for multiple serious conditions, including cancer, and is increasingly recognized as a growing cause of preventable cancer risk. Chronic inflammation, a well-known mediator of cancer, is a central characteristic of obesity, leading to many of its complications, and obesity-induced inflammation confers additional cancer risk beyond obesity itself. Multiple mechanisms facilitate this strong association between cancer and obesity. Adipose tissue is an important endocrine organ, secreting several hormones, including leptin and adiponectin, and chemokines that can regulate tumor behavior, inflammation, and the tumor microenvironment. Excessive adipose expansion during obesity causes adipose dysfunction and inflammation to increase systemic levels of proinflammatory factors. Cells from adipose tissue, such as cancer-associated adipocytes and adipose-derived stem cells, enter the cancer microenvironment to enhance protumoral effects. Dysregulated metabolism that stems from obesity, including insulin resistance, hyperglycemia, and dyslipidemia, can further impact tumor growth and development. This review describes how adipose tissue becomes inflamed in obesity, summarizes ways these mechanisms impact cancer development, and discusses their role in four adipose-associated cancers that demonstrate elevated incidence or mortality in obesity.

Gut REG3γ-Associated Lactobacillus Induces Anti-inflammatory Macrophages to Maintain Adipose Tissue Homeostasis

PubMed Central

Huang, Yugang; Qi, HouBao; Zhang, Zhiqian; Wang, Enlin; Yun, Huan; Yan, Hui; Su, Xiaomin; Liu, Yingquan; Tang, Zenzen; Gao, Yunhuan; Shang, Wencong; Zhou, Jiang; Wang, Tianze; Che, Yongzhe; Zhang, Yuan; Yang, Rongcun

2017-01-01

Gut microbiota may not only affect composition of local immune cells but also affect systemic immune cells. However, it is not completely clear how gut microbiota modulate these immune systems. Here, we found that there exist expanded macrophage pools in huREG3γtgIEC mice. REG3γ-associated Lactobacillus, which is homology to Lactobacillus Taiwanese, could enlarge macrophage pools not only in the small intestinal lamina propria but also in the spleen and adipose tissues. STAT3-mediated signal(s) was a critical factor in the Lactobacillus-mediated anti-inflammatory macrophages. We also offered evidence for critical cellular links among REG3γ-associated Lactobacillus, tissue macrophages, and obesity diseases. Anti-inflammatory macrophages in the lamina propria, which are induced by REG3γ-associated Lactobacillus, may migrate into adipose tissues and are involved in resistance against high-fat diet-mediated obesity. Thus, REG3γ-associated Lactobacillus-induced anti-inflammatory macrophages in gut tissues may play a role in adipose tissue homeostasis. PMID:28928739

Regenerative Repair of Damaged Meniscus with Autologous Adipose Tissue-Derived Stem Cells

PubMed Central

Pak, Jaewoo; Lee, Jung Hun; Lee, Sang Hee

2014-01-01

Mesenchymal stem cells (MSCs) are defined as pluripotent cells found in numerous human tissues, including bone marrow and adipose tissue. Such MSCs, isolated from bone marrow and adipose tissue, have been shown to differentiate into bone and cartilage, along with other types of tissues. Therefore, MSCs represent a promising new therapy in regenerative medicine. The initial treatment of meniscus tear of the knee is managed conservatively with nonsteroidal anti-inflammatory drugs and physical therapy. When such conservative treatment fails, an arthroscopic resection of the meniscus is necessary. However, the major drawback of the meniscectomy is an early onset of osteoarthritis. Therefore, an effective and noninvasive treatment for patients with continuous knee pain due to damaged meniscus has been sought. Here, we present a review, highlighting the possible regenerative mechanisms of damaged meniscus with MSCs (especially adipose tissue-derived stem cells (ASCs)), along with a case of successful repair of torn meniscus with significant reduction of knee pain by percutaneous injection of autologous ASCs into an adult human knee. PMID:24592390

Dwarfism and increased adiposity in the gh1 mutant zebrafish vizzini.

PubMed

McMenamin, Sarah K; Minchin, James E N; Gordon, Tiffany N; Rawls, John F; Parichy, David M

2013-04-01

Somatic growth and adipogenesis are closely associated with the development of obesity in humans. In this study, we identify a zebrafish mutant, vizzini, that exhibits both a severe defect in somatic growth and increased accumulation of adipose tissue. Positional cloning of vizzini revealed a premature stop codon in gh1. Although the effects of GH are largely through igfs in mammals, we found no decrease in the expression of igf transcripts in gh1 mutants during larval development. As development progressed, however, we found overall growth to be progressively retarded and the attainment of specific developmental stages to occur at abnormally small body sizes relative to wild type. Moreover, both subcutaneous (sc) and visceral adipose tissues underwent precocious development in vizzini mutants, and at maturity, the sizes of different fat deposits were greatly expanded relative to wild type. In vivo confocal imaging of sc adipose tissue (SAT) expansion revealed that vizzini mutants exhibit extreme enlargement of adipocyte lipid droplets without a corresponding increase in lipid droplet number. These findings suggest that GH1 signaling restricts SAT hypertrophy in zebrafish. Finally, nutrient deprivation of vizzini mutants revealed that SAT mobilization was greatly diminished during caloric restriction, further implicating GH1 signaling in adipose tissue homeostasis. Overall, the zebrafish gh1 mutant, vizzini, exhibits decreased somatic growth, increased adipose tissue accumulation, and disrupted adipose plasticity after nutrient deprivation and represents a novel model to investigate the in vivo dynamics of vertebrate obesity.

Dwarfism and Increased Adiposity in the gh1 Mutant Zebrafish vizzini

PubMed Central

McMenamin, Sarah K.; Minchin, James E.N.; Gordon, Tiffany N.

2013-01-01

Somatic growth and adipogenesis are closely associated with the development of obesity in humans. In this study, we identify a zebrafish mutant, vizzini, that exhibits both a severe defect in somatic growth and increased accumulation of adipose tissue. Positional cloning of vizzini revealed a premature stop codon in gh1. Although the effects of GH are largely through igfs in mammals, we found no decrease in the expression of igf transcripts in gh1 mutants during larval development. As development progressed, however, we found overall growth to be progressively retarded and the attainment of specific developmental stages to occur at abnormally small body sizes relative to wild type. Moreover, both subcutaneous (sc) and visceral adipose tissues underwent precocious development in vizzini mutants, and at maturity, the sizes of different fat deposits were greatly expanded relative to wild type. In vivo confocal imaging of sc adipose tissue (SAT) expansion revealed that vizzini mutants exhibit extreme enlargement of adipocyte lipid droplets without a corresponding increase in lipid droplet number. These findings suggest that GH1 signaling restricts SAT hypertrophy in zebrafish. Finally, nutrient deprivation of vizzini mutants revealed that SAT mobilization was greatly diminished during caloric restriction, further implicating GH1 signaling in adipose tissue homeostasis. Overall, the zebrafish gh1 mutant, vizzini, exhibits decreased somatic growth, increased adipose tissue accumulation, and disrupted adipose plasticity after nutrient deprivation and represents a novel model to investigate the in vivo dynamics of vertebrate obesity. PMID:23456361

Lipoprotein lipase activity in surgical patients: influence of trauma and infection.

PubMed

Robin, A P; Askanazi, J; Greenwood, M R; Carpentier, Y A; Gump, F E; Kinney, J M

1981-08-01

Hypertriglyceridemia commonly accompanies clinical sepsis and may be caused by increased hepatic production or decreased clearance of triglyceride from the bloodstream. In contrast, enhanced lipid clearing capacity is usually seen after uncomplicated trauma. The purpose of the study was to determine the role of lipoprotein lipase (LPL) in effecting the above changes. Enzyme activity was assayed in skeletal muscle and adipose tissue biopsy samples from 11 normal subjects and from 17 injured and 11 infected surgical patients. Normal subjects after 4 days of 5% dextrose infusion (D5) showed a significant decrease in adipose tissue LPL activity but no change in skeletal muscle activity. Trauma patients after several days of D5 had higher activity in adipose tissue and higher plasma insulin levels than diet-matched control subjects but showed no change in skeletal muscle activity. Infected patients with high plasma triglyceride levels had significantly decreased LPL activity in both tissues. A linear relationship was found between insulin concentration and adipose tissue LPL activity in normal subjects. We conclude that: (1) low tissue LPL activity in sepsis may result in diminished lipid clearance and contribute to hypertriglyceridemia, (2) after trauma, changes in tissue LPL activity as well as other factors such as altered hemodynamics play a role in determining in vivo lipid clearance, and (3) adipose tissue LPL activity is related to the plasma insulin concentration in normal subjects.

Adipose tissue stem cells in regenerative medicine

PubMed Central

Miana, Vanesa Verónica; González, Elio A Prieto

2018-01-01

Adipose tissue-derived stem cells (ADSCs) are mesenchymal cells with the capacity for self-renewal and multipotential differentiation. This multipotentiality allows them to become adipocytes, chondrocytes, myocytes, osteoblasts and neurocytes among other cell lineages. Stem cells and, in particular, adipose tissue-derived cells, play a key role in reconstructive or tissue engineering medicine as they have already proven effective in developing new treatments. The purpose of this work is to review the applications of ADSCs in various areas of regenerative medicine, as well as some of the risks associated with treatment with ADSCs in neoplastic disease. PMID:29662535

Correlation of TLR4 and KLF7 in Inflammation Induced by Obesity.

PubMed

Wang, Cuizhe; Ha, Xiaodan; Li, Wei; Xu, Peng; Gu, Yajuan; Wang, Tingting; Wang, Yan; Xie, Jianxin; Zhang, Jun

2017-02-01

Objective Recent studies have revealed a link between toll-like receptors (TLRs), Kruppel-like factors (KLFs), and the adipose tissue inflammation associated with obesity. TLR4 is associated with chronic inflammation in obesity. KLF7 is known to play an important role in the differentiation of adipocytes, but its role in visceral adipose tissue inflammation has not yet been investigated. Thus, the objective of this study was to determine the correlation of TLR4 and KLF7 in inflammation induced by obesity. Methods A total of 32 Wistar male rat subjects were fed in the center for experimental animals of Shihezi University. The rats were divided into normal control (NC) and high-fat diet (HFD) group. Surgical instruments were used to collect rats' visceral adipose tissue samples in the 10th week after HFD feeding. Ninety-five Uygur subjects between 20 and 90 years old were enrolled in the present study. The subjects were divided into two groups: the normal control group (NC, 18.0 kg/m 2  ≤ BMI ≤ 23.9 kg/m 2 , n = 50) and the obesity group (OB, BMI ≥ 28 kg/m 2 , n = 45), and visceral adipose tissue was collected from the subjects. Anthropometric and clinical parameters were measured using standard procedures; biochemical indices were detected using the glucose oxidase-peroxidase method and a standardized automatic biochemistry analyzer; the plasma levels of inflammatory factors and adipocytokines were measured by enzyme-linked immunosorbent assay (ELISA); the mRNA and protein expression levels of key genes involved in the inflammatory signaling pathway were measured by real-time PCR and Western blot. Results In rats, compared with the NC group, the weight, Lee's index, waist circumference, visceral fat mass, and the plasma level of Glu, TG, FFA, and TNF-α were higher in the HFD group, while the plasma levels of LPT and APN were significantly lower in the HFD group in the 10th week. Furthermore, compared with the NC group, visceral adipose tissue's mRNA expression levels of TLR4, KLF7, and SRC were higher in the HFD group, and KLF7 was significantly positively correlated with LDL, TLR4, SRC, and IL-6 (P < 0.05). Meanwhile, in the Uygur population, the plasma levels of TG, LDL, and TNF-α in the OB group were significantly higher than those in the NC group (P < 0.05). Moreover, compared with the NC group, visceral adipose tissue's mRNA expression levels of TLR4, KLF7, and SRC were significantly higher in the OB group (P < 0.05), and KLF7 was significantly positively correlated with TC, TLR4, MYD88, SRC, and IL-6 (P < 0.05); the protein expression levels of TLR4 and KLF7 were significantly higher than those in the NC group (P < 0.05). Conclusion Higher expression of TLR4 and KLF7 may play a vital role in the process of inflammation induced by obesity in visceral adipose tissue.

Transcriptomic and metabolomic profiling of chicken adipose tissue in response to insulin neutralization and fasting

PubMed Central

2012-01-01

Background Domestic broiler chickens rapidly accumulate adipose tissue due to intensive genetic selection for rapid growth and are naturally hyperglycemic and insulin resistant, making them an attractive addition to the suite of rodent models used for studies of obesity and type 2 diabetes in humans. Furthermore, chicken adipose tissue is considered as poorly sensitive to insulin and lipolysis is under glucagon control. Excessive fat accumulation is also an economic and environmental concern for the broiler industry due to the loss of feed efficiency and excessive nitrogen wasting, as well as a negative trait for consumers who are increasingly conscious of dietary fat intake. Understanding the control of avian adipose tissue metabolism would both enhance the utility of chicken as a model organism for human obesity and insulin resistance and highlight new approaches to reduce fat deposition in commercial chickens. Results We combined transcriptomics and metabolomics to characterize the response of chicken adipose tissue to two energy manipulations, fasting and insulin deprivation in the fed state. Sixteen to 17 day-old commercial broiler chickens (ISA915) were fed ad libitum, fasted for five hours, or fed but deprived of insulin by injections of anti-insulin serum. Pair-wise contrasts of expression data identified a total of 2016 genes that were differentially expressed after correction for multiple testing, with the vast majority of differences due to fasting (1780 genes). Gene Ontology and KEGG pathway analyses indicated that a short term fast impacted expression of genes in a broad selection of pathways related to metabolism, signaling and adipogenesis. The effects of insulin neutralization largely overlapped with the response to fasting, but with more modest effects on adipose tissue metabolism. Tissue metabolomics indicated unique effects of insulin on amino acid metabolism. Conclusions Collectively, these data provide a foundation for further study into the molecular basis for adipose expansion in commercial poultry and identify potential pathways through which fat accretion may be attenuated in the future through genetic selection or management practices. They also highlight chicken as a useful model organism in which to study the dynamic relationship between food intake, metabolism, and adipose tissue biology. PMID:22938590

Proteomic analysis of adipose tissue during the last weeks of gestation in pure and crossbred Large White or Meishan fetuses gestated by sows of either breed.

PubMed

Gondret, F; Guével, B; Père, M C; Quesnel, H; Billon, Y; Com, E; Canario, L; Louveau, I; Liaubet, L

2018-01-01

The degree of adipose tissue development at birth may influence neonatal survival and subsequent health outcomes. Despite their lower birth weights, piglets from Meishan sows (a fat breed with excellent maternal ability) have a higher survival rate than piglets from Large White sows (a lean breed). To identify the main pathways involved in subcutaneous adipose tissue maturation during the last month of gestation, we compared the proteome and the expression levels of some genes at d 90 and d 110 of gestation in purebred and crossbred Large White or Meishan fetuses gestated by sows of either breed. A total of 52 proteins in fetal subcutaneous adipose tissue were identified as differentially expressed over the course of gestation. Many proteins involved in energy metabolism were more abundant, whereas some proteins participating in cytoskeleton organization were reduced in abundance on d 110 compared with d 90. Irrespective of age, 24 proteins differed in abundance between fetal genotypes, and an interaction effect between fetal age and genotype was observed for 13 proteins. The abundance levels of proteins known to be responsive to nutrient levels such as aldolase and fatty acid binding proteins, as well as the expression levels of FASN, a key lipogenic enzyme, and MLXIPL , a pivotal transcriptional mediator of glucose-related stimulation of lipogenic genes, were elevated in the adipose tissue of pure and crossbred fetuses from Meishan sows. These data suggested that the adipose tissue of these fetuses had superior metabolic functionality, whatever their paternal genes. Conversely, proteins participating in redox homeostasis and apoptotic cell clearance had a lower abundance in Meishan than in Large White fetuses. Time-course differences in adipose tissue protein abundance were revealed between fetal genotypes for a few secreted proteins participating in responses to organic substances, such as alpha-2-HS-glycoprotein, transferrin and albumin. These results underline the importance of not only fetal age but also maternal intrauterine environment in the regulation of several proteins in subcutaneous adipose tissue. These proteins may be used to estimate the maturity grade of piglet neonates.

Relative IGF-1 and IGF-2 gene expression in maternal and fetal tissues from diabetic swine

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wolverton, C.K.; Leaman, D.W.; White, M.E.

1990-02-26

Fourteen pregnant, crossbred gilts were utilized in this study. Seven gilts were injected with alloxan (50 mg/kg) at day 75 of gestation to induce diabetes. Gilts underwent caesarean section on day 105 of gestation. Samples were collected from maternal skeletal muscle, adipose tissue, uterus and endometrium; and from fetal skeletal muscle, adipose tissue, placenta, liver, lung, kidney, heart, brain and spleen. Tissues were frozen in liquid nitrogen for later analysis of IGF-1 and IGF-2 gene expression. Samples were pooled and total RNA was isolated using the guanidine isothiocynate method. Total mRNA was analyzed by dot blot hybridization. Blots were probedmore » with {sup 32}P-cDNA for porcine IGF-1 and rat IGF-2. IGF-1 gene expression in maternal tissues was unaffected by diabetes. Maternal diabetes increased IGF-2 mRNA in maternal adipose tissue but exhibited no effect in muscle or uterus. Expression of IGF-2 by maternal endometrium was decreased by diabetes. Maternal diabetes induced an increase in IGF-1 gene expression in muscle and placenta while causing an increase in IGF-2 expression in fetal liver and placenta. IGF-2 mRNA was lower in lung from fetuses of diabetic mothers than in controls. These results suggest that maternal diabetes alters IGF-1 and IGF-2 gene expression in specific tissues and differential regulation of these genes appears to exist in the mother and developing fetus.« less

Increased expressions of genes and proteins involved in mitochondrial oxidation and antioxidant pathway in adipose tissue of pigs selected for a low residual feed intake.

PubMed

Louveau, I; Vincent, A; Tacher, S; Gilbert, H; Gondret, F

2016-12-01

Adipose tissue is a primary sensor for nutrient availability and regulates many functions including feed intake and energy homeostasis. This study was undertaken to determine the molecular responses of adipose tissue to differences in feed intake and feed efficiency. Subcutaneous adipose tissue was collected from two lines of pigs divergently selected for residual feed intake (RFI), a measure of feed efficiency defined as the difference between actual and expected feed intake, and from a subset of high-RFI pigs that were feed-restricted at the level of the voluntary feed intake of low-RFI pigs during the growing-finishing period. Transcriptomics analyses indicated that the number of genes that were differentially expressed ( < 0.01) between low- and high-RFI pigs ( = 8 per group at each stage) in adipose tissue was much lower when pigs were considered at 19 kg (postweaning) than at 115 kg BW (market weight). Extended investigations were performed at 115 kg BW to compare low-RFI ( = 8), high-RFI ( = 8), and feed-restricted high-RFI ( = 8) pigs. They included in silico pathway analyses of the differentially expressed (DE) genes ( < 0.01) and a complementary proteomic investigation to list adipose proteins with a differential abundance ( < 0.10). Only 23% of the DE genes were affected by both RFI and feed restriction. This indicates that the responses of adipose tissue to RFI difference shared only some common mechanisms with feed intake modulation, notably the regulation of cell cycle (including ) and transferase activity pathway. Two carboxylesterase genes (, ) involved in lipolysis, were among the most overexpressed genes in the low-RFI pigs; they were also affected by feed restriction within the high-RFI line. About 60% of the molecular changes between low- and high-RFI pigs were specific to genetic divergence in feed efficiency, independently of feed intake. Different genes and proteins known to be associated with mitochondrial oxidative metabolism were overexpressed in adipose tissue of low-RFI pigs compared with high-RFI pigs; other proteins participating in the generation of energy were also affected by feed restriction within the high-RFI line. Finally, mitochondrial antioxidant genes were upregulated in low-RFI pigs vs. high-RFI pigs. Altogether, increased oxidative and antioxidant processes in adipose tissue might be associated with improved feed efficiency.