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Sample records for brown fat cell

  1. Intricate Transcriptional Networks of Classical Brown and Beige Fat Cells.

    PubMed

    Park, Jun Hong; Hur, Wonhee; Lee, Sean Bong

    2015-01-01

    Brown adipocytes are a specialized cell type that is critical for adaptive thermogenesis, energy homeostasis, and metabolism. In response to cold, both classical brown fat and the newly identified "beige" or "brite" cells are activated by β-adrenergic signaling and catabolize stored lipids and carbohydrates to produce heat via UCP1. Once thought to be non-existent in adults, recent studies have discovered active classical brown and beige fat cells in humans, thus reinvigorating interest in brown and beige adipocytes. This review will focus on the newly discovered transcription factors and microRNAs that specify and orchestrate the classical brown and beige fat cell development.

  2. Histochemical study of brown-fat cells in the golden hamster (Mesocricetus auratus) in cultures

    SciTech Connect

    Sokolov, V.E.; Boyadzhieva-Mikhailova, A.; Koncheva, L.; Angelova, P.; Evgen'eva, T.P.

    1985-11-01

    The authors undertake the task of studying the synthesis of certain hormones by brown-fat cells. The authors used brown-fat cells from the golden hamster. The metabolism of brown-fat cells was studied on precultured cells, which made it possible to detect the synthesis of the studied substances rather than their accumulation in the organ. The authors conducted three experiments. First, fragments of brown fat were cultivated in diffusion chambers in vivo. Pieces of brown fat were cultivated in parallel in vitro on agar (organotypic cultures) and on plasma (histotypic cultures). During cultivation in diffusion chambers, the chambers were implanted in the abdominal cavity of young white rats. For in vitro cultivation, TCM 199 plus 15-20% calf serum was used. A total of 36 cultures with 12 cultures in each series of experiments were performed. The auto-radiographic studies of brown-fat cells were conducted on 24-hour cultures and on brown-fat fragments taken from the intact animal. The cultures were incubated with isotopes for 1 h. Either (/sup 3/H)lysine (87.3 Ci/mM specific activity), (/sup 3/H)arginine (16.7 Ci/mM), (/sup 3/H)glycerol (43 Ci/mM), or (/sup 3/H)cholesterol (43 Ci/mM) were added to the medium. After incubation, the cultures were washed three times in pure medium, fixed in Sierra fluid, and embedded in paraffin. The paraffin sections were covered with Ilford K/sub 2/ emulsion, and the preparations were exposed for 20 days at 4/sup 0/C temperature. Radio-immunological methods were used to study the accumulation of estradiol-17-beta in the culture medium by the Dobson method and that of testerone. The culture medium was taken on cultivation days 2,4,6,8, and 10. The medium was changed during cultivation every third day, which made it possible to judge the rates of accumulation of material with increase in the cultivation times.

  3. Dynamic Regulation of Genes Involved in Mitochondrial DNA Replication and Transcription during Mouse Brown Fat Cell Differentiation and Recruitment

    PubMed Central

    Murholm, Maria; Dixen, Karen; Qvortrup, Klaus; Hansen, Lillian H. L.; Amri, Ez-Zoubir; Madsen, Lise; Barbatelli, Giorgio; Quistorff, Bjørn; Hansen, Jacob B.

    2009-01-01

    Background Brown adipocytes are specialised in dissipating energy through adaptive thermogenesis, whereas white adipocytes are specialised in energy storage. These essentially opposite functions are possible for two reasons relating to mitochondria, namely expression of uncoupling protein 1 (UCP1) and a remarkably higher mitochondrial abundance in brown adipocytes. Methodology/Principal Findings Here we report a comprehensive characterisation of gene expression linked to mitochondrial DNA replication, transcription and function during white and brown fat cell differentiation in vitro as well as in white and brown fat, brown adipose tissue fractions and in selected adipose tissues during cold exposure. We find a massive induction of the majority of such genes during brown adipocyte differentiation and recruitment, e.g. of the mitochondrial transcription factors A (Tfam) and B2 (Tfb2m), whereas only a subset of the same genes were induced during white adipose conversion. In addition, PR domain containing 16 (PRDM16) was found to be expressed at substantially higher levels in brown compared to white pre-adipocytes and adipocytes. We demonstrate that forced expression of Tfam but not Tfb2m in brown adipocyte precursor cells promotes mitochondrial DNA replication, and that silencing of PRDM16 expression during brown fat cell differentiation blunts mitochondrial biogenesis and expression of brown fat cell markers. Conclusions/Significance Using both in vitro and in vivo model systems of white and brown fat cell differentiation, we report a detailed characterisation of gene expression linked to mitochondrial biogenesis and function. We find significant differences in differentiating white and brown adipocytes, which might explain the notable increase in mitochondrial content observed during brown adipose conversion. In addition, our data support a key role of PRDM16 in triggering brown adipocyte differentiation, including mitochondrial biogenesis and expression of UCP1

  4. Pico calorimeter for detection of heat produced in an individual brown fat cell

    NASA Astrophysics Data System (ADS)

    Inomata, Naoki; Toda, Masaya; Sato, Masaaki; Ishijima, Akihiko; Ono, Takahito

    2012-04-01

    A pico calorimeter with a highly sensitive sensor for detecting heat from a biological cell is developed and evaluated, and also the heat detection of a single brown fat cell has been demonstrated. The measurement principle relies on resonant frequency tracking of a resonator in temperature variation due to the heat from the sample; the resonator is placed in vacuum, and heat is conducted from the sample in the microfluidic channel via a heat guide. This configuration can prevent heat loss from the resonator to the surroundings and damping in water. The heat resolution of the fabricated sensor is 5.2 pJ. Heat emissions from single cells are detected as pulsed or continuous in the absence and presence of stimulation, respectively.

  5. 3D brown adipogenesis to create “Brown-Fat-in-Microstrands”

    PubMed Central

    Unser, Andrea M.; Mooney, Bridget; Corr, David T.; Tseng, Yu-Hua; Xie, Yubing

    2015-01-01

    The ability of brown adipocytes (fat cells) to dissipate energy as heat shows great promise for the treatment of obesity and other metabolic disorders. Employing pluripotent stem cells, with an emphasis on directed differentiation, may overcome many issues currently associated with primary fat cell cultures. In addition, three-dimensional (3D) cell culture systems are needed to better understand the role of brown adipocytes in energy balance and treating obesity. To address this need, we created 3D “Brown-Fat-in-Microstrands” by microfluidic synthesis of alginate hydrogel microstrands that encapsulated cells and directly induced cell differentiation into brown adipocytes, using mouse embryonic stem cells (ESCs) as a model of pluripotent stem cells, and brown preadipocytes as a positive control. Brown adipocyte differentiation within microstrands was confirmed by immunocytochemistry and qPCR analysis of the expression of the brown adipocyte-defining marker uncoupling protein 1 (UCP1), as well as other general adipocyte markers. Cells within microstrands were responsive to a β-adrenergic agonist with an increase in gene expression of thermogenic UCP1, indicating that these “Brown-Fat-in-Micrtostrands” are functional. The ability to create “Brown-Fat-in-Microstrands” from pluripotent stem cells opens up a new arena to understanding brown adipogenesis and its implications in obesity and metabolic disorders. PMID:26496384

  6. Brown and Beige Fat: Molecular Parts of a Thermogenic Machine

    PubMed Central

    Cohen, Paul

    2015-01-01

    The epidemic of obesity and type 2 diabetes has increased interest in pathways that affect energy balance in mammalian systems. Brown fat, in all of its dimensions, can increase energy expenditure through the dissipation of chemical energy in the form of heat, using mitochondrial uncoupling and perhaps other pathways. We discuss here some of the thermodynamic and cellular aspects of recent progress in brown fat research. This includes studies of developmental lineages of UCP1+ adipocytes, including the discovery of beige fat cells, a new thermogenic cell type. We also discuss the physiology and transcriptional control of brown and beige cells in rodents and the state of current knowledge about human brown fat. PMID:26050670

  7. Thyroid hormones induce browning of white fat

    PubMed Central

    Martínez-Sánchez, Noelia; Moreno-Navarrete, José M; Contreras, Cristina; Rial-Pensado, Eva; Fernø, Johan; Nogueiras, Rubén; Diéguez, Carlos

    2016-01-01

    The canonical view about the effect of thyroid hormones (THs) on thermogenesis assumes that the hypothalamus acts merely as a modulator of the sympathetic outflow on brown adipose tissue (BAT). Recent data have challenged that vision by demonstrating that THs act on the ventromedial nucleus of the hypothalamus (VMH) to inhibit AMP-activated protein kinase (AMPK), which regulates the thermogenic program in BAT, leading to increased thermogenesis and weight loss. Current data have shown that in addition to activation of brown fat, the browning of white adipose tissue (WAT) might also be an important thermogenic mechanism. However, the possible central effects of THs on the browning of white fat remain unclear. Here, we show that 3,3′,5,5′ tetraiodothyroxyne (T4)-induced hyperthyroidism promotes a marked browning of WAT. Of note, central or VMH-specific administration of 3,3′,5-triiodothyronine (T3) recapitulates that effect. The specific genetic activation of hypothalamic AMPK in the VMH reversed the central effect of T3 on browning. Finally, we also showed that the expression of browning genes in human WAT correlates with serum T4. Overall, these data indicate that THs induce browning of WAT and that this mechanism is mediated via the central effects of THs on energy balance. PMID:27913573

  8. DDE in brown and white fat of hibernating bats

    USGS Publications Warehouse

    Clark, D.R.; Krynitsky, A.J.

    1983-01-01

    Samples of brown and white fat from hibernating bats (big brown bat, Eptesicus fuscus; little brown bat, Myotis lucifugus; and eastern pipistrelle, Pipistrellus subflavus) collected in western Maryland, USA, were analysed to determine lipid and DDE content. Amounts of brown fat, expressed as percentages of total bat weight, were the same for all three species. Lipid content of brown fat was significantly less than that of white fat. Lipids of brown fat contained significantly higher (28%) concentrations of DDE than did lipids of white fat. In our mixed-species sample of 14 bats, concentrations of DDE increased exponentially in both brown and white fat as white fat reserves declined. Brown fat facilitates arousal from hibernation by producing heat through rapid metabolism of triglycerides. The question is raised whether organochlorine residues, such as DDE, may be concentrated and then liberated in lethal amounts by the processes of hibernation and arousal.

  9. Brown adipogenesis of mouse embryonic stem cells in alginate microstrands

    NASA Astrophysics Data System (ADS)

    Unser, Andrea Mannarino

    The ability of brown adipocytes (fat cells) to dissipate energy as heat shows great promise for the treatment of obesity and other metabolic disorders. Employing pluripotent stem cells, with an emphasis on directed differentiation, may overcome many issues currently associated with primary fat cell cultures. However, brown adipocytes are difficult to transplant in vivo due to the instability of fat, in terms of necrosis and neovascularization, once injected. Thus, 3D cell culture systems that have the potential to mimic adipogenic microenvironments are needed, not only to advance brown fat implantation, but also to better understand the role of brown adipocytes in treating obesity. To address this need, we created 3D "Brown-Fat-in-Microstrands" by microfluidic synthesis of alginate hydrogel microstrands that encapsulated cells and directly induced cell differentiation into brown adipocytes, using mouse embryonic stem cells (ESCs) as a model of pluripotent stem cells and brown preadipocytes as a positive control. The effect of hydrogel formation parameters on brown adipogenesis was studied, leading to the establishment of "Brown-Fat-in-Microstrands". Brown adipocyte differentiation within microstrands was confirmed by lipid droplet accumulation, immunocytochemistry and qPCR analysis of gene expression of brown adipocyte marker uncoupling protein 1 (UCP1) in addition to adipocyte marker expression. Compared to a 2D approach, 3D differentiated "Brown-Fat-in-Microstrands" exhibited higher level of brown adipocyte marker expression. The functional analysis of "Brown-Fat-in-Microstrands" was attempted by measuring the mitochondrial activity of ESC-differentiated brown adipocytes in 3D using Seahorse XF24 3 Extracellular Flux Analyzer. The ability to create "Brown-Fat-in-Microstrands" from pluripotent stem cells opens up a new arena to understanding brown adipogenesis and its implications in obesity and metabolic disorders.

  10. Identification of inducible brown adipocyte progenitors residing in skeletal muscle and white fat

    PubMed Central

    Schulz, Tim J.; Huang, Tian Lian; Tran, Thien T.; Zhang, Hongbin; Townsend, Kristy L.; Shadrach, Jennifer L.; Cerletti, Massimiliano; McDougall, Lindsay E.; Giorgadze, Nino; Tchkonia, Tamara; Schrier, Denis; Falb, Dean; Kirkland, James L.; Wagers, Amy J.; Tseng, Yu-Hua

    2011-01-01

    Brown fat is specialized for energy expenditure and has therefore been proposed to function as a defense against obesity. Despite recent advances in delineating the transcriptional regulation of brown adipocyte differentiation, cellular lineage specification and developmental cues specifying brown-fat cell fate remain poorly understood. In this study, we identify and isolate a subpopulation of adipogenic progenitors (Sca-1+/CD45−/Mac1−; referred to as Sca-1+ progenitor cells, ScaPCs) residing in murine brown fat, white fat, and skeletal muscle. ScaPCs derived from different tissues possess unique molecular expression signatures and adipogenic capacities. Importantly, although the ScaPCs from interscapular brown adipose tissue (BAT) are constitutively committed brown-fat progenitors, Sca-1+ cells from skeletal muscle and subcutaneous white fat are highly inducible to differentiate into brown-like adipocytes upon stimulation with bone morphogenetic protein 7 (BMP7). Consistent with these findings, human preadipocytes isolated from subcutaneous white fat also exhibit the greatest inducible capacity to become brown adipocytes compared with cells isolated from mesenteric or omental white fat. When muscle-resident ScaPCs are re-engrafted into skeletal muscle of syngeneic mice, BMP7-treated ScaPCs efficiently develop into adipose tissue with brown fat-specific characteristics. Importantly, ScaPCs from obesity-resistant mice exhibit markedly higher thermogenic capacity compared with cells isolated from obesity-prone mice. These data establish the molecular characteristics of tissue-resident adipose progenitors and demonstrate a dynamic interplay between these progenitors and inductive signals that act in concert to specify brown adipocyte development. PMID:21173238

  11. Proteomic identification of fat-browning markers in cultured white adipocytes treated with curcumin.

    PubMed

    Kim, Sang Woo; Choi, Jae Heon; Mukherjee, Rajib; Hwang, Ki-Chul; Yun, Jong Won

    2016-04-01

    We previously reported that curcumin induces browning of primary white adipocytes via enhanced expression of brown adipocyte-specific genes. In this study, we attempted to identify target proteins responsible for this fat-browning effect by analyzing proteomic changes in cultured white adipocytes in response to curcumin treatment. To elucidate the role of curcumin in fat-browning, we conducted comparative proteomic analysis of primary adipocytes between control and curcumin-treated cells using two-dimensional electrophoresis combined with MALDI-TOF-MS. We also investigated fatty acid metabolic targets, mitochondrial biogenesis, and fat-browning-associated proteins using combined proteomic and network analyses. Proteomic analysis revealed that 58 protein spots from a total of 325 matched spots showed differential expression between control and curcumin-treated adipocytes. Using network analysis, most of the identified proteins were proven to be involved in various metabolic and cellular processes based on the PANTHER classification system. One of the most striking findings is that hormone-sensitive lipase (HSL) was highly correlated with main browning markers based on the STRING database. HSL and two browning markers (UCP1, PGC-1α) were co-immunoprecipitated with these markers, suggesting that HSL possibly plays a role in fat-browning of white adipocytes. Our results suggest that curcumin increased HSL levels and other browning-specific markers, suggesting its possible role in augmentation of lipolysis and suppression of lipogenesis by trans-differentiation from white adipocytes into brown adipocytes (beige).

  12. Cell biology of fat storage

    PubMed Central

    Cohen, Paul; Spiegelman, Bruce M.

    2016-01-01

    The worldwide epidemic of obesity and type 2 diabetes has greatly increased interest in the biology and physiology of adipose tissues. Adipose (fat) cells are specialized for the storage of energy in the form of triglycerides, but research in the last few decades has shown that fat cells also play a critical role in sensing and responding to changes in systemic energy balance. White fat cells secrete important hormone-like molecules such as leptin, adiponectin, and adipsin to influence processes such as food intake, insulin sensitivity, and insulin secretion. Brown fat, on the other hand, dissipates chemical energy in the form of heat, thereby defending against hypothermia, obesity, and diabetes. It is now appreciated that there are two distinct types of thermogenic fat cells, termed brown and beige adipocytes. In addition to these distinct properties of fat cells, adipocytes exist within adipose tissue, where they are in dynamic communication with immune cells and closely influenced by innervation and blood supply. This review is intended to serve as an introduction to adipose cell biology and to familiarize the reader with how these cell types play a role in metabolic disease and, perhaps, as targets for therapeutic development. PMID:27528697

  13. Ouabain-sensitive component of brown fat thermogenesis.

    NASA Technical Reports Server (NTRS)

    Horwitz, B. A.

    1973-01-01

    The study discussed was undertaken to quantify the amount of energy utilized by the ouabain-sensitive Na(+)-K(+) membrane pump during the norepinephrine-induced thermogenesis of brown adipose tissue. The data obtained indicate that the observed inhibition of the catecholamine-induced increase in brown fat thermogenesis by ouabain does not reflect an inhibition of cyclic AMP synthesis.

  14. Mir193b-365 is essential for brown fat differentiation.

    PubMed

    Sun, Lei; Xie, Huangming; Mori, Marcelo A; Alexander, Ryan; Yuan, Bingbing; Hattangadi, Shilpa M; Liu, Qingqing; Kahn, C Ronald; Lodish, Harvey F

    2011-07-10

    Mammals have two principal types of fat. White adipose tissue primarily serves to store extra energy as triglycerides, whereas brown adipose tissue is specialized to burn lipids for heat generation and energy expenditure as a defence against cold and obesity. Recent studies have demonstrated that brown adipocytes arise in vivo from a Myf5-positive, myoblastic progenitor by the action of Prdm16 (PR domain containing 16). Here, we identified a brown-fat-enriched miRNA cluster, MiR-193b-365, as a key regulator of brown fat development. Blocking miR-193b and/or miR-365 in primary brown preadipocytes markedly impaired brown adipocyte adipogenesis by enhancing Runx1t1 (runt-related transcription factor 1; translocated to, 1) expression, whereas myogenic markers were significantly induced. Forced expression of Mir193b and/or Mir365 in C2C12 myoblasts blocked the entire programme of myogenesis, and, in adipogenic conditions, miR-193b induced myoblasts to differentiate into brown adipocytes. Mir193b-365 was upregulated by Prdm16 partially through Pparα. Our results demonstrate that Mir193b-365 serves as an essential regulator for brown fat differentiation, in part by repressing myogenesis.

  15. White to brown fat phenotypic switch induced by genetic and environmental activation of a hypothalamic-adipocyte axis

    PubMed Central

    Cao, Lei; Choi, Eugene Y.; Liu, Xianglan; Martin, Adam; Wang, Chuansong; Xu, Xiaohua; During, Matthew J.

    2011-01-01

    SUMMARY Living in an enriched environment with complex physical and social stimulation leads to improved cognitive and metabolic health. In white fat, enrichment induced the upregulation of the brown fat cell fate determining gene Prdm16, brown fat specific markers, and genes involved in thermogenesis and β-adrenergic signaling. Moreover, pockets of cells with prototypical brown fat morphology and high UCP1 levels were observed in the white fat of enriched mice associated with resistance to diet-induced obesity. Hypothalamic overexpression of BDNF reproduced the enrichment-associated activation of the brown fat gene program and lean phenotype. Inhibition of BDNF signaling by genetic knockout or dominant negative trkB reversed this phenotype. Our genetic and pharmacologic data suggest a mechanism whereby induction of hypothalamic BDNF expression in response to environmental stimuli leads to selective sympathoneural modulation of white fat to induce “browning” and increased energy dissipation. PMID:21907139

  16. The lipid sensor GPR120 promotes brown fat activation and FGF21 release from adipocytes

    PubMed Central

    Quesada-López, Tania; Cereijo, Rubén; Turatsinze, Jean-Valery; Planavila, Anna; Cairó, Montserrat; Gavaldà-Navarro, Aleix; Peyrou, Marion; Moure, Ricardo; Iglesias, Roser; Giralt, Marta; Eizirik, Decio L.; Villarroya, Francesc

    2016-01-01

    The thermogenic activity of brown adipose tissue (BAT) and browning of white adipose tissue are important components of energy expenditure. Here we show that GPR120, a receptor for polyunsaturated fatty acids, promotes brown fat activation. Using RNA-seq to analyse mouse BAT transcriptome, we find that the gene encoding GPR120 is induced by thermogenic activation. We further show that GPR120 activation induces BAT activity and promotes the browning of white fat in mice, whereas GRP120-null mice show impaired cold-induced browning. Omega-3 polyunsaturated fatty acids induce brown and beige adipocyte differentiation and thermogenic activation, and these effects require GPR120. GPR120 activation induces the release of fibroblast growth factor-21 (FGF21) by brown and beige adipocytes, and increases blood FGF21 levels. The effects of GPR120 activation on BAT activation and browning are impaired in FGF21-null mice and cells. Thus, the lipid sensor GPR120 activates brown fat via a mechanism that involves induction of FGF21. PMID:27853148

  17. Browning of White Fat: Novel Insight Into Factors, Mechanisms, and Therapeutics.

    PubMed

    Jeremic, Nevena; Chaturvedi, Pankaj; Tyagi, Suresh C

    2017-01-01

    What is more interesting about brown adipose tissue (BAT) is its ability to provide thermogenesis, protection against obesity by clearing triglycerides, releasing batokines, and mitigating insulin resistance. White adipose tissue (WAT) on the other hand stores excess energy and secretes some endocrine factors like leptin for regulating satiety. For the last decade there has been an increasing interest in the browning of fat keeping in view its beneficial effects on metabolic disorders and protection in the form of perivascular fat. Obesity is one such metabolic disorder that leads to significant morbidity and mortality from obesity-related disorders such as type 2 diabetes mellitus (T2D) and cardiovascular disease risk. Browning of white fat paves the way to restrict obesity and obesity related disorders. Although exercise has been the most common factor for fat browning; however, there are other factors that involve: (1) beta aminoisobutyric acid (BAIBA); (2) gamma amino butyric acid (GABA); (3) PPARɣ agonists; (4) JAK inhibition; and (5) IRISIN. In this review, we propose two novel factors musclin and TFAM for fat browning. Musclin a myokine released from muscles during exercise activates PPARɣ which induces browning of WAT that has beneficial metabolic and cardiac effects. TFAM is a transcription factor that induces mitochondrial biogenesis. Since BAT is rich in mitochondria, higher expression of TFAM in WAT or TFAM treatment in WAT cells can induce browning of WAT. We propose that fat browning can be used as a therapeutic tool for metabolic disorders and cardiovascular diseases. J. Cell. Physiol. 232: 61-68, 2017. © 2016 Wiley Periodicals, Inc.

  18. Brown and beige fat: Physiological roles beyond heat-generation

    PubMed Central

    Kajimura, Shingo; Spiegelman, Bruce M.; Seale, Patrick

    2015-01-01

    Since brown adipose tissue (BAT) dissipates energy through UCP1, BAT has garnered attention as a therapeutic intervention for obesity and metabolic diseases including type2 diabetes. As we better understand the physiological roles of classical brown and beige adipocytes, it is becoming clear that BAT is not simply a heat-generating organ. Increased beige fat mass in response to a variety of external/internal cues is associated with significant improvements in glucose and lipid homeostasis that may not be entirely mediated by UCP1. We aim to discuss recent insights regarding the developmental lineages, molecular regulation, and new functions for brown and beige adipocytes. PMID:26445512

  19. Brown Fat Fuel Utilization and Thermogenesis

    PubMed Central

    Townsend, Kristy L.; Tseng, Yu-Hua

    2014-01-01

    Brown adipose tissue (BAT) dissipates energy as heat to maintain optimal thermogenesis and to contribute to energy expenditure, in rodents and possibly humans. The energetic processes executed by BAT require a readily available fuel supply, which includes glucose and fatty acids (FAs). FAs become available by cellular uptake, de novo lipogenesis, and from multilocular lipid droplets in brown adipocytes. BAT also possesses a great capacity for glucose uptake and metabolism, and an ability to regulate insulin sensitivity. These properties make BAT an appealing target for the treatment of obesity, diabetes and other metabolic disorders. Recent research has revealed a better understanding of the processes of fuel utilization carried out by brown adipocytes, which is the focus of the current review. PMID:24389130

  20. Novel function of the retinoblastoma protein in fat: regulation of white versus brown adipocyte differentiation.

    PubMed

    Hansen, Jacob B; te Riele, Hein; Kristiansen, Karsten

    2004-06-01

    The differentiation of white and brown fat cells is controlled by a similar set of transcription factors, including PPARgamma and C/EBPalpha. However, despite many similarities between the two types of fat cells, they carry out essentially opposite functions in vivo, with white adipocytes being the major energy store and brown adipocytes being potent energy-dissipaters through thermogenesis. Yet, little is known about factors differentially regulating the formation of white and brown fat cells. Members of the retinoblastoma protein family (pRB, p107, p130) have been implicated in the regulation of adipocyte differentiation, and expression and phosphorylation of the three retinoblastoma family proteins oscillate in a characteristic manner during differentiation of the white preadipocyte cell line 3T3-L1. We have recently demonstrated a surprising function of the retinoblastoma protein in the regulation of white versus brown adipocyte differentiation in vitro and possibly in vivo. Here we summarize the current knowledge on the retinoblastoma protein in fat cells, with particular emphasis on its potential role in adipocyte lineage commitment and differentiation.

  1. Human Brown Fat and Obesity: Methodological Aspects

    PubMed Central

    van Marken Lichtenbelt, Wouter

    2011-01-01

    Much is known about brown adipose tissue (BAT) in rodents. Its function is to generate heat in response to low environmental temperatures and to diet or overfeeding. The knowledge about BAT in humans is still rather limited despite the recent rediscovery of its functionality in adults. This review highlights the information available on the contribution of BAT in increasing human energy expenditure in relation to obesity. Besides that methodological aspects will be discussed that need special attention in order to unravel the heat producing capacity of human BAT, the recruitment of the tissue, and its functionality. PMID:22654813

  2. Role of PRDM16 in the activation of brown fat programming. Relevance to the development of obesity.

    PubMed

    Becerril, Sara; Gómez-Ambrosi, Javier; Martín, Marina; Moncada, Rafael; Sesma, Pilar; Burrell, María A; Frühbeck, Gema

    2013-11-01

    From a histological and functional point of view, two types of adipose tissue can be identified. As opposed to the mainly unilocular white adipocytes, brown adipocytes possess plenty of small multilocular lipid droplets and dissipate energy as heat. Moreover, two distinct types of brown adipose cells exist. In vivo fate mapping experiments of brown adipose tissue (BAT) precursors suggest that classical brown adipocytes and skeletal myoblasts originate from a common mesenchymal, myogenic factor 5 (Myf5)-positive precursor cell. In addition to the classical brown adipocytes, thermogenic brown-like adipocytes (brite/beige cells) may appear within white adipose tissue (WAT) depots, sharing many of the morphological and functional features of brown adipocytes, but arising from a Myf5-negative lineage. In humans, the conversion of white fat cells into brite adipocytes could be a strategy to increase energy expenditure. The zinc finger transcription factor Prdm16 controls the bidirectional fate decision between brown adipocytes and myoblasts. Prdm16 determines the brown fat-like programme and thermogenesis in both brown and white adipose tissues. Moreover, the expression of this transcriptional regulator is strongly correlated with beige cell-selective genes. From a therapeutical point of view, the potential of inducing BAT or the transdifferentiation of WAT into beige cells by enhancing Prdm16 expression, as well as the identification of mechanisms of Prdm16 function and regulation represent potentially exciting new approaches for treatment or prevention of obesity and related diseases.

  3. Near-Infrared Photoluminescent Carbon Nanotubes for Imaging of Brown Fat

    PubMed Central

    Yudasaka, Masako; Yomogida, Yohei; Zhang, Minfang; Tanaka, Takeshi; Nakahara, Masako; Kobayashi, Norihiko; Okamatsu-Ogura, Yuko; Machida, Ken; Ishihara, Kazuhiko; Saeki, Kumiko; Kataura, Hiromichi

    2017-01-01

    Near-infrared photoluminescent single-walled carbon nanotubes (CNTs) are expected to provide effectual bio-imaging tools, although, as yet, only limited applications have been reported. Here, we report that CNTs coated with an amphiphilic and biocompatible polymer, poly(2-methacryloyloxyethyl phosphorylcholine-co-n-butyl methacrylate; PMB), generate high-quality images of brown fat. Brown fat is a heat-productive adipose tissue, which is attracting increasing attention as a new therapeutic target for obesity-associated metabolic disorders. Its brown colour is mainly attributed to densely packed capillaries, which facilitate its high heat-exchanging efficiency. Currently, positron emission tomography-computed tomography is the only practical technique to identify brown fat distribution in the living body; however, it is expensive to use. By virtue of their high affinity to apolipoproteins and exemption from macrophage phagocytosis, PMB-CNTs selectively accumulate on capillary endothelial cells but not larger vessels in adipose tissue. Therefore, the image brightness of adipose tissue can directly reflect the capillary density, and indirectly the thermogenic capability and brownness. PMB-CNTs provide clearer images than conventional organic dyes, as the high level of transmitted light passes through the body with less light scattering. Thus, PMB-CNT-based imaging methods could open a new phase in thermogenic adipose tissue research. PMID:28317858

  4. Brown fat in a protoendothermic mammal fuels eutherian evolution.

    PubMed

    Oelkrug, Rebecca; Goetze, Nadja; Exner, Cornelia; Lee, Yang; Ganjam, Goutham K; Kutschke, Maria; Müller, Saskia; Stöhr, Sigrid; Tschöp, Matthias H; Crichton, Paul G; Heldmaier, Gerhard; Jastroch, Martin; Meyer, Carola W

    2013-01-01

    Endothermy has facilitated mammalian species radiation, but the sequence of events leading to sustained thermogenesis is debated in multiple evolutionary models. Here we study the Lesser hedgehog tenrec (Echinops telfairi), a phylogenetically ancient, 'protoendothermic' eutherian mammal, in which constantly high body temperatures are reported only during reproduction. Evidence for nonshivering thermogenesis is found in vivo during periodic ectothermic-endothermic transitions. Anatomical studies reveal large brown fat-like structures in the proximity of the reproductive organs, suggesting physiological significance for parental care. Biochemical analysis demonstrates high mitochondrial proton leak catalysed by an uncoupling protein 1 ortholog. Strikingly, bioenergetic profiling of tenrec uncoupling protein 1 reveals similar thermogenic potency as modern mouse uncoupling protein 1, despite the large phylogenetic distance. The discovery of functional brown adipose tissue in this 'protoendothermic' mammal links nonshivering thermogenesis directly to the roots of eutherian evolution, suggesting physiological importance prior to sustained body temperatures and migration to the cold.

  5. Brown fat in a protoendothermic mammal fuels eutherian evolution

    PubMed Central

    Oelkrug, Rebecca; Goetze, Nadja; Exner, Cornelia; Lee, Yang; Ganjam, Goutham K.; Kutschke, Maria; Müller, Saskia; Stöhr, Sigrid; Tschöp, Matthias H.; Crichton, Paul G.; Heldmaier, Gerhard; Jastroch, Martin; Meyer, Carola W.

    2013-01-01

    Endothermy has facilitated mammalian species radiation, but the sequence of events leading to sustained thermogenesis is debated in multiple evolutionary models. Here we study the Lesser hedgehog tenrec (Echinops telfairi), a phylogenetically ancient, ‘protoendothermic’ eutherian mammal, in which constantly high body temperatures are reported only during reproduction. Evidence for nonshivering thermogenesis is found in vivo during periodic ectothermic–endothermic transitions. Anatomical studies reveal large brown fat-like structures in the proximity of the reproductive organs, suggesting physiological significance for parental care. Biochemical analysis demonstrates high mitochondrial proton leak catalysed by an uncoupling protein 1 ortholog. Strikingly, bioenergetic profiling of tenrec uncoupling protein 1 reveals similar thermogenic potency as modern mouse uncoupling protein 1, despite the large phylogenetic distance. The discovery of functional brown adipose tissue in this ‘protoendothermic’ mammal links nonshivering thermogenesis directly to the roots of eutherian evolution, suggesting physiological importance prior to sustained body temperatures and migration to the cold. PMID:23860571

  6. Bone marrow fat has brown adipose tissue characteristics, which are attenuated with aging and diabetes.

    PubMed

    Krings, A; Rahman, S; Huang, S; Lu, Y; Czernik, P J; Lecka-Czernik, B

    2012-02-01

    Fat occupies a significant portion of bone cavity however its function is largely unknown. Marrow fat expands during aging and in conditions which affect energy metabolism, indicating that fat in bone is under similar regulatory mechanisms as other fat depots. On the other hand, its location may determine specific functions in the maintenance of the environment for bone remodeling and hematopoiesis. We have demonstrated that marrow fat has a distinctive phenotype, which resembles both, white and brown adipose tissue (WAT and BAT, respectively). Marrow adipocytes express gene markers of brown adipocytes at levels characteristic for the BAT, including transcription factor Prdm16, and regulators of thermogenesis such as deiodinase 2 (Dio2) and PGC1α. The levels of expression of BAT-specific gene markers are decreased in bone of 24 mo old C57BL/6 and in diabetic yellow agouti A(vy)/a mice implicating functional changes of marrow fat occurring with aging and diabetes. Administration of antidiabetic TZD rosiglitazone, which sensitizes cells to insulin and increases adipocyte metabolic functions, significantly increased both, BAT (UCP1, PGC1α, Dio2, β3AR, Prdm16, and FoxC2) and WAT (adiponectin and leptin) gene expression in marrow of normoglycemic C57BL/6 mice, but failed to increase the expression of BAT, but not WAT, gene markers in diabetic mice. In conclusion, the metabolic phenotype of marrow fat combines both BAT and WAT characteristics. Decrease in BAT-like characteristics with aging and diabetes may contribute to the negative changes in the marrow environment supporting bone remodeling and hematopoiesis.

  7. Programming human pluripotent stem cells into white and brown adipocytes

    PubMed Central

    Ahfeldt, Tim; Schinzel, Robert T.; Lee, Youn-Kyoung; Hendrickson, David; Kaplan, Adam; Lum, David H.; Camahort, Raymond; Xia, Fang; Shay, Jennifer; Rhee, Eugene P.; Clish, Clary B.; Deo, Rahul C.; Shen, Tony; Lau, Frank H.; Cowley, Alicia; Mowrer, Greg; Al-Siddiqi, Heba; Nahrendorf, Matthias; Musunuru, Kiran; Gerszten, Robert E.; Rinn, John L.; Cowan, Chad A.

    2012-01-01

    The utility of human pluripotent stem cells is dependent on efficient differentiation protocols that convert these cells into relevant adult cell types. Here we report the robust and efficient differentiation of human pluripotent stem cells into white or brown adipocytes. We found that inducible expression of PPARG2 alone or combined with CEBPB and/or PRDM16 in mesenchymal progenitor cells derived from pluripotent stem cells programmed their development towards a white or brown adipocyte cell fate with efficiencies of 85%–90%. These adipocytes retained their identity independent of transgene expression, could be maintained in culture for several weeks, expressed mature markers and had mature functional properties such as lipid catabolism and insulin-responsiveness. When transplanted into mice, the programmed cells gave rise to ectopic fat pads with the morphological and functional characteristics of white or brown adipose tissue. These results indicate that the cells could be used to faithfully model human disease. PMID:22246346

  8. Pathology of Murine Cytomegalovirus Infection in Newborn Mice. Muscle, Heart and Brown Fat Lesions

    PubMed Central

    Lussier, G.

    1974-01-01

    Newborn mice were inoculated intracerebrally with murine cytomegalovirus and studies were made of the pathological changes in the striate and cardiac muscle and brown fat. Widespread necrosis was seen in muscle and brown fat in the early stages of the infection. Necrotic lesions became calcified. By 56 days lesions were not resolved in the heart and brown fat but were completely resolved in skeletal muscle. ImagesFig. 1.Fig. 2.Fig. 3.Fig. 4.Fig. 5.Fig. 6.Fig. 7.Fig. 8.Fig. 9. PMID:4363374

  9. Browning of subcutaneous fat and higher surface temperature in response to phenotype selection for advanced endurance exercise performance in male DUhTP mice.

    PubMed

    Brenmoehl, J; Ohde, D; Albrecht, E; Walz, C; Tuchscherer, A; Hoeflich, A

    2017-02-01

    For the assessment of genetic or conditional factors of fat cell browning, novel and polygenic animal models are required. Therefore, the long-term selected polygenic mouse line DUhTP originally established in Dummerstorf for high treadmill performance is used. DUhTP mice are characterized by increased fat accumulation in the sedentary condition and elevated fat mobilization during mild voluntary physical activity. In the present study, the phenotype of fat cell browning of subcutaneous fat and a potential effect on oral glucose tolerance, an indicator of metabolic health, were addressed in DUhTP mice. Analysis of peripheral fat pads revealed increased brite (brown-in-white) subcutaneous adipose tissues and in subcutaneous fat from DUhTP mice higher levels of irisin and different markers of fat cell browning like T-box transcription factor (Tbx1), PPARα, and uncoupling protein (UCP1) (P < 0.05) when compared to unselected controls. UCP1 was further increased in subcutaneous fat from DUhTP mice in response to mild exercise (fourfold, P < 0.05). In addition, surface temperature of DUhTP mice was increased when compared to controls indicating a physiological effect of increased UCP1 expression. The present study suggests that DUhTP mice exhibit different markers of mitochondrial biogenesis and fat browning without external stimuli. At an age of 43 days, sedentary DUhTP mice have improved metabolic health as judged from lower levels of blood glucose after an oral glucose tolerance test. Consequently, the non-inbred mouse model DUhTP represents a novel model for the identification of fat cell browning mechanisms in white adipose tissues.

  10. Eicosapentaenoic acid regulates brown adipose tissue metabolism in high-fat-fed mice and in clonal brown adipocytes.

    PubMed

    Pahlavani, Mandana; Razafimanjato, Fitia; Ramalingam, Latha; Kalupahana, Nishan S; Moussa, Hanna; Scoggin, Shane; Moustaid-Moussa, Naima

    2017-01-01

    Brown adipose tissue (BAT) plays a key role in energy expenditure through its specialized thermogenic function. Therefore, BAT activation may help prevent and/or treat obesity. Interestingly, subcutaneous white adipose tissue (WAT) also has the ability to differentiate into brown-like adipocytes and may potentially contribute to increased thermogenesis. We have previously reported that eicosapentaenoic acid (EPA) reduces high-fat (HF)-diet-induced obesity and insulin resistance in mice. Whether BAT mediates some of these beneficial effects of EPA has not been determined. We hypothesized that EPA activates BAT thermogenic program, contributing to its antiobesity effects. BAT and WAT were harvested from B6 male mice fed HF diets supplemented with or without EPA. HIB 1B clonal brown adipocytes treated with or without EPA were also used. Gene and protein expressions were measured in adipose tissues and H1B 1B cells by quantitative polymerase chain reaction and immunoblotting, respectively. Our results show that BAT from EPA-supplemented mice expressed significantly higher levels of thermogenic genes such as PRDM16 and PGC1α and higher levels of uncoupling protein 1 compared to HF-fed mice. By contrast, both WATs (subcutaneous and visceral) had undetectable levels of these markers with no up regulation by EPA. HIB 1B cells treated with EPA showed significantly higher mRNA expression of PGC1α and SIRT2. EPA treatment significantly increased maximum oxidative and peak glycolytic metabolism in H1B 1B cells. Our results demonstrate a novel and promising role for EPA in preventing obesity via activation of BAT, adding to its known beneficial anti-inflammatory effects.

  11. Ebf2 is a selective marker of brown and beige adipogenic precursor cells.

    PubMed

    Wang, Wenshan; Kissig, Megan; Rajakumari, Sona; Huang, Li; Lim, Hee-Woong; Won, Kyoung-Jae; Seale, Patrick

    2014-10-07

    Brown adipocytes and muscle and dorsal dermis descend from precursor cells in the dermomyotome, but the factors that regulate commitment to the brown adipose lineage are unknown. Here, we prospectively isolated and determined the molecular profile of embryonic brown preadipose cells. Brown adipogenic precursor activity in embryos was confined to platelet-derived growth factor α(+), myogenic factor 5(Cre)-lineage-marked cells. RNA-sequence analysis identified early B-cell factor 2 (Ebf2) as one of the most selectively expressed genes in this cell fraction. Importantly, Ebf2-expressing cells purified from Ebf2(GFP) embryos or brown fat tissue did not express myoblast or dermal cell markers and uniformly differentiated into brown adipocytes. Interestingly, Ebf2-expressing cells from white fat tissue in adult animals differentiated into brown-like (or beige) adipocytes. Loss of Ebf2 in brown preadipose cells reduced the expression levels of brown preadipose-signature genes, whereas ectopic Ebf2 expression in myoblasts activated brown preadipose-specific genes. Altogether, these results indicate that Ebf2 specifically marks and regulates the molecular profile of brown preadipose cells.

  12. Brown and beige fat in humans: thermogenic adipocytes that control energy and glucose homeostasis

    PubMed Central

    Sidossis, Labros; Kajimura, Shingo

    2015-01-01

    Brown adipose tissue (BAT), a specialized fat that dissipates energy to produce heat, plays an important role in the regulation of energy balance. Two types of thermogenic adipocytes with distinct developmental and anatomical features exist in rodents and humans: classical brown adipocytes and beige (also referred to as brite) adipocytes. While classical brown adipocytes are located mainly in dedicated BAT depots of rodents and infants, beige adipocytes sporadically reside with white adipocytes and emerge in response to certain environmental cues, such as chronic cold exposure, a process often referred to as “browning” of white adipose tissue. Recent studies indicate the existence of beige adipocytes in adult humans, making this cell type an attractive therapeutic target for obesity and obesity-related diseases, including type 2 diabetes. This Review aims to cover recent progress in our understanding of the anatomical, developmental, and functional characteristics of brown and beige adipocytes and discuss emerging questions, with a special emphasis on adult human BAT. PMID:25642708

  13. Brown fat thermogenesis: Stability of developmental programming and transient effects of temperature and gut microbiota in adults.

    PubMed

    Ziętak, Marika; Chabowska-Kita, Agnieszka; Kozak, Leslie Paul

    2017-03-01

    Evidence from animal studies continues to document the effectiveness of brown fat based thermogenesis in stimulating energy expenditure to reduce obesity. Evidence shows that the number of brown adipocytes in white fat is determined by developmental mechanisms, not the environment. The large variability in the capacity for brown fat thermogenesis comes from genetic variability in developmental mechanisms extent in the animal. This genetic variability ultimately drives the capacity for induction of the brown adipocyte phenotype in response to environmental signals in adult animals. We highlight recent studies that suggest a role for gut microbiota in the regulation of brown fat thermogenesis that is based, in part, upon the observation that bile acids can effectively induce thermogenesis by interscapular brown fat at thermoneutrality.

  14. Inducible Brown Adipose Tissue, or Beige Fat, Is Anabolic for the Skeleton

    PubMed Central

    Rahman, Sima; Lu, Yalin; Czernik, Piotr J.; Rosen, Clifford J.; Enerback, Sven

    2013-01-01

    It is known that insulin resistance and type 2 diabetes mellitus are associated with increased fractures and that brown adipose tissue (BAT) counteracts many if not all of the symptoms associated with type 2 diabetes. By the use of FoxC2AD+/Tg mice, a well-established model for induction of BAT, or beige fat, we present data extending the beneficial action of beige fat to also include a positive effect on bone. FoxC2AD+/Tg mice are lean and insulin-sensitive and have high bone mass due to increased bone formation associated with high bone turnover. Inducible BAT is linked to activation of endosteal osteoblasts whereas osteocytes have decreased expression of the Sost transcript encoding sclerostin and elevated expression of Rankl. Conditioned media (CM) collected from forkhead box c2 (FOXC2)-induced beige adipocytes activated the osteoblast phenotype and increased levels of phospho-AKT and β-catenin in recipient cells. In osteocytes, the same media decreased Sost expression. Immunodepletion of CM with antibodies against wingless related MMTV integration site 10b (WNT10b) and insulin-like growth factor binding protein 2 (IGFBP2) resulted in the loss of pro-osteoblastic activity, and the loss of increase in the levels of phospho-AKT and β-catenin. Conversely, CM derived from cells overexpressing IGFBP2 or WNT10b restored osteoblastic activity in recipient cells. In conclusion, beige fat secretes endocrine/paracrine activity that is beneficial for the skeleton. PMID:23696565

  15. Identification of a new supraclavicular brown fat depot in mice

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The rediscovery of brown adipose tissue (BAT) in healthy adult humans raises the possibility of utilizing BAT to combat obesity and its related metabolic disorders. Adult humans possess limited amounts of BAT with the most thermoactive depot located in the supraclavicular area of the neck. Understan...

  16. Eicosapentaenoic acid regulates brown adipose tissue gene expression and metabolism in high fat fed mice

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Brown adipose tissue (BAT) is a thermogenic tissue, a key regulator of energy balance and a potential therapeutic target for obesity. We previously reported that eicosapentaenoic acid (EPA) reduced high fat (HF) diet-induced obesity and insulin resistance in mice, independent of energy intake. We hy...

  17. BMP4-mediated brown fat-like changes in white adipose tissue alter glucose and energy homeostasis.

    PubMed

    Qian, Shu-Wen; Tang, Yan; Li, Xi; Liu, Yuan; Zhang, You-You; Huang, Hai-Yan; Xue, Rui-Dan; Yu, Hao-Yong; Guo, Liang; Gao, Hui-Di; Liu, Yan; Sun, Xia; Li, Yi-Ming; Jia, Wei-Ping; Tang, Qi-Qun

    2013-02-26

    Expression of bone morphogenetic protein 4 (BMP4) in adipocytes of white adipose tissue (WAT) produces "white adipocytes" with characteristics of brown fat and leads to a reduction of adiposity and its metabolic complications. Although BMP4 is known to induce commitment of pluripotent stem cells to the adipocyte lineage by producing cells that possess the characteristics of preadipocytes, its effects on the mature white adipocyte phenotype and function were unknown. Forced expression of a BMP4 transgene in white adipocytes of mice gives rise to reduced WAT mass and white adipocyte size along with an increased number of a white adipocyte cell types with brown adipocyte characteristics comparable to those of beige or brite adipocytes. These changes correlate closely with increased energy expenditure, improved insulin sensitivity, and protection against diet-induced obesity and diabetes. Conversely, BMP4-deficient mice exhibit enlarged white adipocyte morphology and impaired insulin sensitivity. We identify peroxisome proliferator-activated receptor gamma coactivator 1-α (PGC1α) as the target of BMP signaling required for these brown fat-like changes in WAT. This effect of BMP4 on WAT appears to extend to human adipose tissue, because the level of expression of BMP4 in WAT correlates inversely with body mass index. These findings provide a genetic and metabolic basis for BMP4's role in altering insulin sensitivity by affecting WAT development.

  18. [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.

  19. Dipeptidyl peptidase IV inhibitor lowers PPARγ agonist-induced body weight gain by affecting food intake, fat mass, and beige/brown fat but not fluid retention

    PubMed Central

    Masuda, Takahiro; Fu, Yiling; Eguchi, Akiko; Czogalla, Jan; Rose, Michael A.; Kuczkowski, Alexander; Gerasimova, Maria; Feldstein, Ariel E.; Scadeng, Miriam

    2013-01-01

    Peroxisome proliferator-activated receptor-γ (PPARγ) agonists like pioglitazone (PGZ) are effective antidiabetic drugs, but they induce fluid retention and body weight (BW) gain. Dipeptidyl peptidase IV (DPP IV) inhibitors are antidiabetic drugs that enhance renal Na+ and fluid excretion. Therefore, we examined whether the DPP IV inhibitor alogliptin (ALG) ameliorates PGZ-induced BW gain. Male Sv129 mice were treated with vehicle (repelleted diet), PGZ (220 mg/kg diet), ALG (300 mg/kg diet), or a combination of PGZ and ALG (PGZ + ALG) for 14 days. PGZ + ALG prevented the increase in BW observed with PGZ but did not attenuate the increase in body fluid content determined by bioimpedance spectroscopy (BIS). BIS revealed that ALG alone had no effect on fat mass (FM) but enhanced the FM-lowering effect of PGZ; MRI analysis confirmed the latter and showed reductions in visceral and inguinal subcutaneous (sc) white adipose tissue (WAT). ALG but not PGZ decreased food intake and plasma free fatty acid concentrations. Conversely, PGZ but not ALG increased mRNA expression of thermogenesis mediator uncoupling protein 1 in epididymal WAT. Adding ALG to PGZ treatment increased the abundance of multilocular cell islets in sc WAT, and PGZ + ALG increased the expression of brown-fat-like “beige” cell marker TMEM26 in sc WAT and interscapular brown adipose tissue and increased rectal temperature vs. vehicle. In summary, DPP IV inhibition did not attenuate PPARγ agonist-induced fluid retention but prevented BW gain by reducing FM. This involved ALG inhibition of food intake and was associated with food intake-independent synergistic effects of PPARγ agonism and DPP-IV inhibition on beige/brown fat cells and thermogenesis. PMID:24347054

  20. Ubc9 Impairs Activation of the Brown Fat Energy Metabolism Program in Human White Adipocytes.

    PubMed

    Hartig, Sean M; Bader, David A; Abadie, Kathleen V; Motamed, Massoud; Hamilton, Mark P; Long, Weiwen; York, Brian; Mueller, Michaela; Wagner, Martin; Trauner, Michael; Chan, Lawrence; Bajaj, Mandeep; Moore, David D; Mancini, Michael A; McGuire, Sean E

    2015-09-01

    Insulin resistance and type 2 diabetes mellitus (T2DM) result from an inability to efficiently store and catabolize surplus energy in adipose tissue. Subcutaneous adipocytes protect against insulin resistance and T2DM by coupling differentiation with the induction of brown fat gene programs for efficient energy metabolism. Mechanisms that disrupt these programs in adipocytes are currently poorly defined, but represent therapeutic targets for the treatment of T2DM. To gain insight into these mechanisms, we performed a high-throughput microscopy screen that identified ubiquitin carrier protein 9 (Ubc9) as a negative regulator of energy storage in human sc adipocytes. Ubc9 depletion enhanced energy storage and induced the brown fat gene program in human sc adipocytes. Induction of adipocyte differentiation resulted in decreased Ubc9 expression commensurate with increased brown fat gene expression. Thiazolidinedione treatment reduced the interaction between Ubc9 and peroxisome proliferator-activated receptor (PPAR)γ, suggesting a mechanism by which Ubc9 represses PPARγ activity. In support of this hypothesis, Ubc9 overexpression remodeled energy metabolism in human sc adipocytes by selectively inhibiting brown adipocyte-specific function. Further, Ubc9 overexpression decreased uncoupling protein 1 expression by disrupting PPARγ binding at a critical uncoupling protein 1 enhancer region. Last, Ubc9 is significantly elevated in sc adipose tissue isolated from mouse models of insulin resistance as well as diabetic and insulin-resistant humans. Taken together, our findings demonstrate a critical role for Ubc9 in the regulation of sc adipocyte energy homeostasis.

  1. Exercise Increases and Browns Muscle Lipid in High-Fat Diet-Fed Mice

    PubMed Central

    Morton, Tiffany L.; Galior, Kornelia; McGrath, Cody; Wu, Xin; Uzer, Gunes; Uzer, Guniz Bas; Sen, Buer; Xie, Zhihui; Tyson, David; Rubin, Janet; Styner, Maya

    2016-01-01

    Muscle lipid increases with high-fat feeding and diabetes. In trained athletes, increased muscle lipid is not associated with insulin resistance, a phenomenon known as the athlete’s paradox. To understand if exercise altered the phenotype of muscle lipid, female C57BL/6 mice fed CTL or high-fat diet (HFD for 6 or 18 weeks) were further divided into sedentary or exercising groups (CTL-E or HFD-E) with voluntary access to running wheels for the last 6 weeks of experiments, running 6 h/night. Diet did not affect running time or distance. HFD mice weighed more than CTL after 18 weeks (p < 0.01). Quadriceps muscle TG was increased in running animals and in sedentary mice fed HFD for 18 weeks (p < 0.05). In exercised animals, markers of fat, Plin1, aP2, FSP27, and Fasn, were increased significantly in HFD groups. Ucp1 and Pgc1a, markers for brown fat, increased with exercise in the setting of high fat feeding. Fndc5, which encodes irisin, and CytC were sensitive to exercise regardless of diet. Plin5 was increased with HFD and unaffected by exercise; the respiratory exchange ratio was 15% lower in the 18-week HFD group compared with CTL (p < 0.001) and 10% lower in 18 weeks HFD-E compared with CTL-E (p < 0.001). Increased Ucp1 and Pgc1a in exercised muscle of running mice suggests that a beige/brown fat phenotype develops, which differs from the fat phenotype that induces insulin resistance in high fat feeding. This suggests that increased muscle lipid may develop a “brown” phenotype in the setting of endurance exercise training, a shift that is further promoted by HFD. PMID:27445983

  2. Brown fat activation reduces hypercholesterolaemia and protects from atherosclerosis development

    PubMed Central

    Berbée, Jimmy F. P.; Boon, Mariëtte R; Khedoe, P. Padmini S. J.; Bartelt, Alexander; Schlein, Christian; Worthmann, Anna; Kooijman, Sander; Hoeke, Geerte; Mol, Isabel M.; John, Clara; Jung, Caroline; Vazirpanah, Nadia; Brouwers, Linda P.J.; Gordts, Philip L.S.M.; Esko, Jeffrey D.; Hiemstra, Pieter S.; Havekes, Louis M.; Scheja, Ludger; Heeren, Joerg; Rensen, Patrick C.N.

    2015-01-01

    Brown adipose tissue (BAT) combusts high amounts of fatty acids, thereby lowering plasma triglyceride levels and reducing obesity. However, the precise role of BAT in plasma cholesterol metabolism and atherosclerosis development remains unclear. Here we show that BAT activation by β3-adrenergic receptor stimulation protects from atherosclerosis in hyperlipidemic APOE*3-Leiden.CETP mice, a well-established model for human-like lipoprotein metabolism that unlike hyperlipidemic Apoe−/− and Ldlr−/− mice expresses functional apoE and LDLR. BAT activation increases energy expenditure and decreases plasma triglyceride and cholesterol levels. Mechanistically, we demonstrate that BAT activation enhances the selective uptake of fatty acids from triglyceride-rich lipoproteins into BAT, subsequently accelerating the hepatic clearance of the cholesterol-enriched remnants. These effects depend on a functional hepatic apoE-LDLR clearance pathway as BAT activation in Apoe−/− and Ldlr−/− mice does not attenuate hypercholesterolaemia and atherosclerosis. We conclude that activation of BAT is a powerful therapeutic avenue to ameliorate hyperlipidaemia and protect from atherosclerosis. PMID:25754609

  3. Metabolically inert perfluorinated fatty acids directly activate uncoupling protein 1 in brown-fat mitochondria.

    PubMed

    Shabalina, Irina G; Kalinovich, Anastasia V; Cannon, Barbara; Nedergaard, Jan

    2016-05-01

    The metabolically inert perfluorinated fatty acids perfluorooctane sulfonate (PFOS) and perfluorooctanoate (PFOA) can display fatty acid-like activity in biological systems. The uncoupling protein 1 (UCP1) in brown adipose tissue is physiologically (re)activated by fatty acids, including octanoate. This leads to bioenergetically uncoupled energy dissipation (heat production, thermogenesis). We have examined here the possibility that PFOA/PFOS can directly (re)activate UCP1 in isolated mouse brown-fat mitochondria. In wild-type brown-fat mitochondria, PFOS and PFOA overcame GDP-inhibited thermogenesis, leading to increased oxygen consumption and dissipated membrane potential. The absence of this effect in brown-fat mitochondria from UCP1-ablated mice indicated that it occurred through activation of UCP1. A competitive type of inhibition by increased GDP concentrations indicated interaction with the same mechanistic site as that utilized by fatty acids. No effect was observed in heart mitochondria, i.e., in mitochondria without UCP1. The stimulatory effect of PFOA/PFOS was not secondary to non-specific mitochondrial membrane permeabilization or to ROS production. Thus, metabolic effects of perfluorinated fatty acids could include direct brown adipose tissue (UCP1) activation. The possibility that this may lead to unwarranted extra heat production and thus extra utilization of food resources, leading to decreased fitness in mammalian wildlife, is discussed, as well as possible negative effects in humans. However, a possibility to utilize PFOA-/PFOS-like substances for activating UCP1 therapeutically in obesity-prone humans may also be envisaged.

  4. [Progress in dedifferentiated fat cells].

    PubMed

    Cheng, Feifei; Yang, Zhi; Qian, Cheng

    2014-10-01

    When mature adipocytes are subjected to an in vitro dedifferentiation strategy referred to as ceiling culture, these mature adipocytes can revert to dedifferentiated fat (DFAT) cells. DFAT cells have many advantages compared with adipose-derived stem cells (ASCs) and bone marrow mesenchymal stem cells (BMSCs). For example, DFAT cells are homogeneous and could be obtained from donors regardless of their age. Furthermore, DFAT cells also have the same multi-lineage potentials and low immunogenicity as ASCs. As an excellent source of seed cells for tissue engineering and stem cell transplantation, DFAT cells have better prospects in the treatment of many clinical diseases, such as bone defects, neurological diseases, ischemic heart disease and kidney disease. It is necessary to make more intensive studies of DFAT cells. This article summarizes progresses in the immunological characteristics, differentiation ability and potential clinical applications of DFAT cells.

  5. Characterization of beta-adrenergic receptors and adenylate cyclase activity in rat brown fat

    SciTech Connect

    Baresi, L.A.; Morley, J.E.; Scarpace, P.J.

    1986-03-01

    Catecholamines stimulate thermogenesis in rat brown fat through a mechanism which involves binding to the beta-adrenergic receptor (BAR), stimulation of adenylate cyclase (AC) and culminating with uncoupling of mitochondrial respiration from ATP synthesis. The authors characterized BAR, AC and cytochrome (cyt) c oxidase in CDF (F-344) interscapular brown fat. Scatchard analysis of (/sup 125/)Iodopindolol binding yields a straight line consistent with a single class of antagonist binding sites with 41.8 +/- 12.0 fmol BAR/mg protein and a K/sub d/ of 118 +/- 15 pM. Binding was both specific and stereospecific. Competition with 1-propranolol (K/sub d/ = 6.7 nM) was 15 times more potent than d-propranolol (K/sub d/ = 103 nM). Competition with isoproterenol (K/sub d/ = 79 nM) was 10 times more potent than epinephrine (K/sub d/ = 820 nM) which was 35 times more potent than norepinephrine (K/sub d/ = 2.9 x 10/sup -5/ M) suggesting predominate beta/sub 2/-type BAR. Cyt c oxidase activity was assessed in brown fat mitochrondrial preparations. The ratio of BAR to cyt c activity was 959 +/- 275 nmol BAR/mol cyc c/min. Isoproterenol (0.1 mM) stimulated AC activity was 24 times GTP (0.1 mM) stimulated AC (98.5 vs 40.7 pmol cAMP/min/mg). NaF-stimulated AC was nine times basal activity (90.5 vs 11.3 pmol cAMP/min/mg). These data demonstrate the presence of a beta-/sub 2/-type BAR coupled to adenylate cyclase in rat brown fat.

  6. Effect of Intermittent Cold Exposure on Brown Fat Activation, Obesity, and Energy Homeostasis in Mice

    PubMed Central

    Ravussin, Yann; Xiao, Cuiying; Gavrilova, Oksana; Reitman, Marc L.

    2014-01-01

    Homeotherms have specific mechanisms to maintain a constant core body temperature despite changes in thermal environment, food supply, and metabolic demand. Brown adipose tissue, the principal thermogenic organ, quickly and efficiently increases heat production by dissipating the mitochondrial proton motive force. It has been suggested that activation of brown fat, via either environmental (i.e. cold exposure) or pharmacologic means, could be used to increase metabolic rate and thus reduce body weight. Here we assess the effects of intermittent cold exposure (4°C for one to eight hours three times a week) on C57BL/6J mice fed a high fat diet. Cold exposure increased metabolic rate approximately two-fold during the challenge and activated brown fat. In response, food intake increased to compensate fully for the increased energy expenditure; thus, the mice showed no reduction in body weight or adiposity. Despite the unchanged adiposity, the cold-treated mice showed transient improvements in glucose homeostasis. Administration of the cannabinoid receptor-1 inverse agonist AM251 caused weight loss and improvements in glucose homeostasis, but showed no further improvements when combined with cold exposure. These data suggest that intermittent cold exposure causes transient, meaningful improvements in glucose homeostasis, but without synergy when combined with AM251. Since energy expenditure is significantly increased during cold exposure, a drug that dissociates food intake from metabolic demand during cold exposure may achieve weight loss and further metabolic improvements. PMID:24465761

  7. Fat accumulation in differentiated brown adipocytes is linked with expression of Hox genes.

    PubMed

    Singh, Smita; Rajput, Yudhishthir S; Barui, Amit K; Sharma, Rajan; Datta, Tirtha K

    2016-03-01

    Homeobox (Hox) genes are involved in body plan of embryo along the anterior-posterior axis. Presence of several Hox genes in white adipose tissue (WAT) and brown adipose tissue (BAT) is indicative of involvement of Hox genes in adipogenesis. We propose that differentiation inducing agents viz. isobutyl-methyl-xanthine (IBMX), indomethacin, dexamethasone (DEX), triiodothyronine (T3) and insulin may regulate differentiation in brown adipose tissue through Hox genes. In vitro culture of brown fat stromalvascular fraction (SVF) in presence or absence of differentiation inducing agents was used for establishing relationship between fat accumulation in differentiated adipocytes and expression of Hox genes. Relative expression of Pref1, UCP1 and Hox genes was determined in different stages of adipogenesis. Presence or absence of IBMX, indomethacin and DEX during differentiation of proliferated pre-adipocytes resulted in marked differences in expression of Hox genes and lipid accumulation. In presence of these inducing agents, lipid accumulation as well as expression of HoxA1, HoxA5, HoxC4 &HoxC8 markedly enhanced. Irrespective of presence or absence of T3, insulin down regulates HoxA10. T3 results in over expression of HoxA5, HoxC4 and HoxC8 genes, whereas insulin up regulates expression of only HoxC8. Findings suggest that accumulation of fat in differentiated adipocytes is linked with expression of Hox genes.

  8. FGF21, energy expenditure and weight loss – How much brown fat do you need?

    PubMed Central

    Straub, Leon; Wolfrum, Christian

    2015-01-01

    Background Fibroblast growth factor 21 (FGF21) belongs to the large family of fibroblast growth factors (FGFs). Even though FGF signaling has been mainly implicated in developmental processes, recent studies have demonstrated that FGF21 is an important regulator of whole body energy expenditure and metabolism, in obesity. Scope of review Given the fact that obesity has developed epidemic proportions, not just in industrialized countries, FGF21 has emerged as a novel therapeutic avenue to treat obesity as well as associated metabolic disorders. While the metabolic effects of FGF21 are undisputed, the mechanisms by which FGF21 regulate weight loss have not yet been fully resolved. Until recently it was believed that FGF21 induces brown fat activity, thereby enhancing energy expenditure, which concomitantly leads to weight loss. Novel studies have challenged this concept as they could demonstrate that a part of the FGF21 mediated effects are retained in a mouse model of impaired brown adipose tissue function. Major conclusions The review illustrates the recent advances in FGF21 research and discusses the role of FGF21 in the regulation of energy expenditure linked to brown fat activity. PMID:26413466

  9. Curcumin induces brown fat-like phenotype in 3T3-L1 and primary white adipocytes.

    PubMed

    Lone, Jameel; Choi, Jae Heon; Kim, Sang Woo; Yun, Jong Won

    2016-01-01

    Recent advances have been made in the understanding of pharmacological and dietary agents that contribute to browning of white adipose tissue in order to combat obesity by promoting energy expenditure. Here, we show that curcumin induces browning of 3T3-L1 and primary white adipocytes via enhanced expression of brown fat-specific genes. Curcumin-induced browning in white adipocytes was investigated by determining expression levels of brown adipocyte-specific genes/proteins by real-time reverse transcriptase polymerase chain reaction, immunoblot analysis and immunocytochemical staining. Curcumin increased mitochondrial biogenesis, as evidenced by transmission electronic microscopic detection and enhanced expression of proteins involved in fat oxidation. Cucurmin also increased protein levels of hormone-sensitive lipase and p-acyl-CoA carboxylase, suggesting its possible role in augmentation of lipolysis and suppression of lipogenesis. Increased expression of UCP1 and other brown adipocyte-specific markers was possibly mediated by curcumin-induced activation of AMP-activated protein kinase (AMPK) based on the fact that inhibition of AMPK by dorsomorphin abolished expression of PRDM16, UCP1 and peroxisome proliferator-activated receptor gamma co-activator 1-alpha while the activator 5-Aminoimidazole-4-carboxamide ribonucleotide elevated expression of these brown marker proteins. Our findings suggest that curcumin plays a dual modulatory role in inhibition of adipogenesis as well as induction of the brown fat-like phenotype and thus may have potential therapeutic implications for treatment of obesity.

  10. The Effects of High Fat Diet and Resveratrol on Mitochondrial Activity of Brown Adipocytes

    PubMed Central

    Cho, Yoon Hee; Hong, Zhen-Yu; Lee, Ha; Lee, Sue Ji; Hong, Seung-soo

    2016-01-01

    Background Resveratrol (RSV) is a polyphenolic phytoalexin that has many effects on metabolic diseases such as diabetes and obesity. Given the importance of brown adipose tissue (BAT) for energy expenditure, we investigated the effects of RSV on brown adipocytes. Methods For the in vitro study, interscapular BAT was isolated from 7-week-old male Sprague Dawley rats. For the in vivo study, 7-week-old male Otsuka Long Evans Tokushima Fatty (OLETF) rats were divided into four groups and treated for 27 weeks with: standard diet (SD); SD+RSV (10 mg/kg body weight, daily); high fat diet (HFD); HFD+RSV. RSV was provided via oral gavage once daily during the in vivo experiments. Results RSV treatment of primary cultured brown preadipocytes promoted mitochondrial activity, along with over-expression of estrogen receptor α (ER-α). In OLETF rats, both HFD and RSV treatment increased the weight of BAT and the differentiation of BAT. However, only RSV increased the mitochondrial activity and ER-α expression of BAT in the HFD-fed group. Finally, RSV improved the insulin sensitivity of OLETF rats by increasing the mitochondrial activity of BAT, despite having no effects on white adipocytes and muscles in either diet group. Conclusion RSV could improve insulin resistance, which might be associated with mitochondrial activity of brown adipocyte. Further studies evaluating the activity of RSV for both the differentiation and mitochondrial activity of BAT could be helpful in investigating the effects of RSV on metabolic parameters. PMID:27077216

  11. Anti-inflammatory and anti-diabetic effects of brown seaweeds in high-fat diet-induced obese mice

    PubMed Central

    Oh, Ji-Hyun; Kim, Jaehoon

    2016-01-01

    BACKGROUND/OBJECTIVES Seaweeds have been reported to have various health beneficial effects. In this study, we investigated the potential anti-obesity and anti-inflammatory effects of four types of domestic brown seaweeds in a high-fat diet-induced obese mouse model and bone marrow-derived macrophages (BMDM). MATERIALS/METHODS Male C57BL/6N mice were fed low-fat diet (LFD), high-fat diet (HFD) or HFD containing Undaria Pinnatifida, HFD containing Laminaria Japonica (LJ), HFD containing Sargassum Fulvellum, or HFD containing Hizikia Fusiforme (HF) for 16 weeks. RESULTS Brown seaweed supplementation did not affect long-term HFD-associated changes in body weight or adiposity, although mice fed HFD + LJ or HFD + HF gained slightly less body weight compared with those fed HFD at the beginning of feeding. Despite being obese, mice fed HFD + LJ appeared to show improved insulin sensitivity compared to mice fed HFD. Consistently, we observed significantly reduced blood glucose concentrations in mice fed HFD + LJ compared with those of mice fed HFD. Although no significant differences in adipocyte size were detected among the HFD-fed groups, consumption of seaweeds decreased formation of HFD-induced crown-like structures in gonadal adipose tissue as well as plasma inflammatory cytokines. BMDM from mice fed HFDs with seaweeds showed differential regulation of pro-inflammatory cytokines such as IL-1β and IL-6 compared with BMDM from mice fed HFD by LPS stimulation. CONCLUSION Although seaweed consumption did not prevent long-term HFD-induced obesity in C57BL/6N mice, it reduced insulin resistance (IR) and circulation of pro-inflammatory cytokines. Therefore, seaweeds may ameliorate systemic inflammation and IR in obesity partially due to inhibition of inflammatory signaling in adipose tissue cells as well as bone marrow-derived immune cells. PMID:26865915

  12. History of fat grafting: from ram fat to stem cells.

    PubMed

    Mazzola, Riccardo F; Mazzola, Isabella C

    2015-04-01

    Fat injection empirically started 100 years ago to correct contour deformities mainly on the face and breast. The German surgeon Eugene Hollaender (1867-1932) proposed a cocktail of human and ram fat, to avoid reabsorption. Nowadays, fat injection has evolved, and it ranks among the most popular procedures, for it provides the physician with a range of aesthetic and reconstructive clinical applications with regenerative effects on the surrounding tissues. New research from all over the world has demonstrated the role of adipose-derived stem cells, present in the adipose tissue, in the repair of damaged or missing tissues.

  13. Leptin Production by Encapsulated Adipocytes Increases Brown Fat, Decreases Resistin, and Improves Glucose Intolerance in Obese Mice

    PubMed Central

    DiSilvestro, David J.; Melgar-Bermudez, Emiliano; Yasmeen, Rumana; Fadda, Paolo; Lee, L. James; Kalyanasundaram, Anuradha; Gilor, Chen L.; Ziouzenkova, Ouliana

    2016-01-01

    The neuroendocrine effects of leptin on metabolism hold promise to be translated into a complementary therapy to traditional insulin therapy for diabetes and obesity. However, injections of leptin can provoke inflammation. We tested the effects of leptin, produced in the physiological adipocyte location, on metabolism in mouse models of genetic and dietary obesity. We generated 3T3-L1 adipocytes constitutively secreting leptin and encapsulated them in a poly-L-lysine membrane, which protects the cells from immune rejection. Ob/ob mice (OB) were injected with capsules containing no cells (empty, OB[Emp]), adipocytes (OB[3T3]), or adipocytes overexpressing leptin (OB[Lep]) into both visceral fat depots. Leptin was found in the plasma of OB[Lep], but not OB[Emp] and OB[3T3] mice at the end of treatment (72 days). The OB[Lep] and OB[3T3] mice have transiently suppressed appetite and weight loss compared to OB[Emp]. Only OB[Lep] mice have greater brown fat mass, metabolic rate, and reduced resistin plasma levels compared to OB[Emp]. Glucose tolerance was markedly better in OB[Lep] vs. OB[Emp] and OB[3T3] mice as well as in wild type mice with high-fat diet-induced obesity and insulin resistance treated with encapsulated leptin-producing adipocytes. Our proof-of-principle study provides evidence of long-term improvement of glucose tolerance with encapsulated adipocytes producing leptin. PMID:27055280

  14. A role for phosphodiesterase 3B in acquisition of brown fat characteristics by white adipose tissue in male mice.

    PubMed

    Guirguis, Emilia; Hockman, Steven; Chung, Youn Wook; Ahmad, Faiyaz; Gavrilova, Oksana; Raghavachari, Nalini; Yang, Yanqin; Niu, Gang; Chen, Xiaoyuan; Yu, Zu Xi; Liu, Shiwei; Degerman, Eva; Manganiello, Vincent

    2013-09-01

    Obesity is linked to various diseases, including insulin resistance, diabetes, and cardiovascular disorders. The idea of inducing white adipose tissue (WAT) to assume characteristics of brown adipose tissue (BAT), and thus gearing it to fat burning instead of storage, is receiving serious consideration as potential treatment for obesity and related disorders. Phosphodiesterase 3B (PDE3B) links insulin- and cAMP-signaling networks in tissues associated with energy metabolism, including WAT. We used C57BL/6 PDE3B knockout (KO) mice to elucidate mechanisms involved in the formation of BAT in epididymal WAT (EWAT) depots. Examination of gene expression profiles in PDE3B KO EWAT revealed increased expression of several genes that block white and promote brown adipogenesis, such as C-terminal binding protein, bone morphogenetic protein 7, and PR domain containing 16, but a clear BAT-like phenotype was not completely induced. However, acute treatment of PDE3B KO mice with the β3-adrenergic agonist, CL316243, markedly increased the expression of cyclooxygenase-2, which catalyzes prostaglandin synthesis and is thought to be important in the formation of BAT in WAT and the elongation of very long-chain fatty acids 3, which is linked to BAT recruitment upon cold exposure, causing a clear shift toward fat burning and the induction of BAT in KO EWAT. These data provide insight into the mechanisms of BAT formation in mouse EWAT, suggesting that, in a C57BL/6 background, an increase in cAMP, caused by ablation of PDE3B and administration of CL316243, may promote differentiation of prostaglandin-responsive progenitor cells in the EWAT stromal vascular fraction into functional brown adipocytes.

  15. Ketone esters increase brown fat in mice and overcome insulin resistance in other tissues in the rat

    PubMed Central

    Veech, Richard L.

    2013-01-01

    Brown adipose tissue (BAT) is classically activated by sympathetic nervous stimulation resulting from exposure to cold. Feeding a high-fat diet also induces development of brown fat, but is decreased by caloric restriction. Blood ketone bodies, which function as alternative energy substrates to glucose, are increased during caloric restriction. Here we discuss the unexpected observation that feeding an ester of ketone bodies to the mouse, which increases blood ketone body concentrations, results in an activation of brown fat. The mechanism of this activation of brown fat is similar to that occurring from cold exposure in that cyclic adenosine monophosphate (AMP) levels are increased as are levels of the transcription factor cyclic AMP–responsive element–binding protein, which is also increased by ketone ester feeding. Other effects of feeding ketone esters, in addition to their ability to induce brown fat, are discussed such as their ability to overcome certain aspects of insulin resistance and to ameliorate the accumulation of amyloid and phosphorylated tau protein in brain, and improve cognitive function, in a triple transgenic mouse model of Alzheimer’s disease. PMID:23909803

  16. Ketone esters increase brown fat in mice and overcome insulin resistance in other tissues in the rat.

    PubMed

    Veech, Richard L

    2013-10-01

    Brown adipose tissue (BAT) is classically activated by sympathetic nervous stimulation resulting from exposure to cold. Feeding a high-fat diet also induces development of brown fat, but is decreased by caloric restriction. Blood ketone bodies, which function as alternative energy substrates to glucose, are increased during caloric restriction. Here we discuss the unexpected observation that feeding an ester of ketone bodies to the mouse, which increases blood ketone body concentrations, results in an activation of brown fat. The mechanism of this activation of brown fat is similar to that occurring from cold exposure in that cyclic adenosine monophosphate (AMP) levels are increased as are levels of the transcription factor cyclic AMP-responsive element-binding protein, which is also increased by ketone ester feeding. Other effects of feeding ketone esters, in addition to their ability to induce brown fat, are discussed such as their ability to overcome certain aspects of insulin resistance and to ameliorate the accumulation of amyloid and phosphorylated tau protein in brain, and improve cognitive function, in a triple transgenic mouse model of Alzheimer's disease.

  17. Effect of Chronic Athletic Activity on Brown Fat in Young Women

    PubMed Central

    Singhal, Vibha; Maffazioli, Giovana D.; Ackerman, Kate E.; Lee, Hang; Elia, Elisa F.; Woolley, Ryan; Kolodny, Gerald; Cypess, Aaron M.; Misra, Madhusmita

    2016-01-01

    Background The effect of chronic exercise activity on brown adipose tissue (BAT) is not clear, with some studies showing positive and others showing negative associations. Chronic exercise is associated with increased resting energy expenditure (REE) secondary to increased lean mass and a probable increase in BAT. Many athletes are in a state of relative energy deficit suggested by lower fat mass and hypothalamic amenorrhea. States of severe energy deficit such as anorexia nervosa are associated with reduced BAT. There are no data regarding the impact of chronic exercise activity on BAT volume or activity in young women and it is unclear whether relative energy deficiency modifies the effects of exercise on BAT. Purpose We assessed cold induced BAT volume and activity in young female athletes compared with non-athletes, and further evaluated associations of BAT with measures of REE, body composition and menstrual status. Methods The protocol was approved by our Institutional Review Board. Written informed consent was obtained from all participants prior to study initiation. This was a cross-sectional study of 24 women (16 athletes and8 non-athletes) between 18–25 years of age. Athletes were either oligo-amenorrheic (n = 8) or eumenorrheic (n = 8).We used PET/CT scans to determine cold induced BAT activity, VMAX Encore 29 metabolic cart to obtain measures of REE, and DXA for body composition. Results Athletes and non-athletes did not differ for age or BMI. Compared with non-athletes, athletes had lower percent body fat (p = 0.002), higher percent lean mass (p = 0.01) and trended higher in REE (p = 0.09). BAT volume and activity in athletes trended lower than in non-athletes (p = 0.06; p = 0.07, respectively). We found negative associations of BAT activity with duration of amenorrhea (r = -0.46, p = 0.02).BAT volume correlated inversely with lean mass (r = -0.46, p = 0.02), and positively with percent body fat, irisin and thyroid hormones. Conclusions Our study

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

    PubMed

    Lin, Ligen; Saha, Pradip K; Ma, Xiaojun; Henshaw, Iyabo O; Shao, Longjiang; Chang, Benny H J; Buras, Eric D; Tong, Qiang; Chan, Lawrence; McGuinness, Owen P; Sun, Yuxiang

    2011-12-01

    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 that ablation of the ghrelin receptor (growth hormone secretagogue receptor, GHS-R) improves insulin sensitivity during aging. Compared to wild-type (WT) mice, old Ghsr(-/-) mice have reduced fat and preserve a healthier lipid profile. Old Ghsr(-/-) mice also exhibit elevated energy expenditure and resting metabolic rate, yet have similar food intake and locomotor activity. While GHS-R expression in white and brown adipose tissues was below the detectable level in the young mice, GHS-R expression was readily detectable in visceral white fat and interscapular brown fat of the old mice. Gene expression profiles reveal that Ghsr ablation reduced glucose/lipid uptake and lipogenesis in white adipose tissues but increased thermogenic capacity in brown adipose tissues. Ghsr ablation prevents age-associated decline in thermogenic gene expression of uncoupling protein 1 (UCP1). Cell culture studies in brown adipocytes further demonstrate that ghrelin suppresses the expression of adipogenic and thermogenic genes, while GHS-R antagonist abolishes ghrelin's effects and increases UCP1 expression. Hence, GHS-R plays an important role in thermogenic impairment during aging. Ghsr ablation improves aging-associated obesity and insulin resistance by reducing adiposity and increasing thermogenesis. Growth hormone secretagogue receptor antagonists may be a new means of combating obesity by shifting the energy balance from obesogenesis to thermogenesis.

  19. Equations of prediction for abdominal fat in brown egg-laying hens fed different diets.

    PubMed

    Souza, C; Jaimes, J J B; Gewehr, C E

    2016-12-03

    The objective was to use noninvasive measurements to formulate equations for predicting the abdominal fat weight of laying hens in a noninvasive manner. Hens were fed with different diets; the external body measurements of birds were used as regressors. We used 288 Hy-Line Brown laying hens, distributed in a completely randomized design in a factorial arrangement, submitted for 16 wk to 2 metabolizable energy levels (2,550 and 2,800 kcal/kg) and 3 levels of crude protein in the diet (150, 160, and 170 g/kg), totaling 6 treatments, with 48 hens each. Sixteen hens per treatment of 92 wk age were utilized to evaluate body weight, bird length, tarsus and sternum, greater and lesser diameter of the tarsus, and abdominal fat weight, after slaughter. The equations were obtained by using measures evaluated with regressors through simple and multiple linear regression with the stepwise method of indirect elimination (backward), with P < 0.10 for all variables remaining in the model. The weight of abdominal fat as predicted by the equations and observed values for each bird were subjected to Pearson's correlation analysis. The equations generated by energy levels showed coefficients of determination of 0.50 and 0.74 for 2,800 and 2,550 kcal/kg of metabolizable energy, respectively, with correlation coefficients of 0.71 and 0.84, with a highly significant correlation between the calculated and observed values of abdominal fat. For protein levels of 150, 160, and 170 g/kg in the diet, it was possible to obtain coefficients of determination of 0.75, 0.57, and 0.61, with correlation coefficients of 0.86, 0.75, and 0.78, respectively. Regarding the general equation for predicting abdominal fat weight, the coefficient of determination was 0.62; the correlation coefficient was 0.79. The equations for predicting abdominal fat weight in laying hens, based on external measurements of the birds, showed positive coefficients of determination and correlation coefficients, thus

  20. Non-Invasive Quantification of White and Brown Adipose Tissues and Liver Fat Content by Computed Tomography in Mice

    PubMed Central

    Lubura, Marko; Hesse, Deike; Neumann, Nancy; Scherneck, Stephan; Wiedmer, Petra; Schürmann, Annette

    2012-01-01

    Objectives Obesity and its distribution pattern are important factors for the prediction of the onset of diabetes in humans. Since several mouse models are suitable to study the pathophysiology of type 2 diabetes the aim was to validate a novel computed tomograph model (Aloka-Hitachi LCT-200) for the quantification of visceral, subcutaneous, brown and intrahepatic fat depots in mice. Methods Different lean and obese mouse models (C57BL/6, B6.V-Lepob, NZO) were used to determine the most adequate scanning parameters for the detection of the different fat depots. The data were compared with those obtained after preparation and weighing the fat depots. Liver fat content was determined by biochemical analysis. Results The correlations between weights of fat tissues on scale and weights determined by CT were significant for subcutaneous (r2 = 0.995), visceral (r2 = 0.990) and total white adipose tissue (r2 = 0.992). Moreover, scans in the abdominal region, between lumbar vertebrae L4 to L5 correlated with whole-body fat distribution allowing experimenters to reduce scanning time and animal exposure to radiation and anesthesia. Test-retest reliability and measurements conducted by different experimenters showed a high reproducibility in the obtained results. Intrahepatic fat content estimated by CT was linearly related to biochemical analysis (r2 = 0.915). Furthermore, brown fat mass correlated well with weighted brown fat depots (r2 = 0.952). In addition, short-term cold-expose (4°C, 4 hours) led to alterations in brown adipose tissue attributed to a reduction in triglyceride content that can be visualized as an increase in Hounsfield units by CT imaging. Conclusion The 3D imaging of fat by CT provides reliable results in the quantification of total, visceral, subcutaneous, brown and intrahepatic fat in mice. This non-invasive method allows the conduction of longitudinal studies of obesity in mice and therefore enables experimenters to investigate

  1. Opposing effects of activation of central GABAA and GABAB receptors on brown fat thermogenesis in the rat.

    PubMed

    Horton, R W; LeFeuvre, R A; Rothwell, N J; Stock, M J

    1988-04-01

    Baclofen (a GABAB agonist) stimulates body temperature, metabolic rate and brown adipose tissue (BAT) in the rat through a central action, but no effects of gamma-aminobutyric acid (GABA) itself on these parameters were observed. In the present study, it was found that the central effects of (+/-)baclofen (0.5-2.0 micrograms injection i.c.v.) on the temperature (1.2 degrees C increase) and metabolic rate (44-76% increase) of brown adipose tissue were inhibited by previous treatment with the GABAA agonist, muscimol (0.05 micrograms). Injection of GABA alone (12 micrograms) did not significantly affect these parameters, but in the presence of the GABAA antagonist bicuculline (2.5 micrograms), GABA significantly increased the temperature (0.3 degrees C) and oxygen consumption (22%) of brown fat. (-)Baclofen was found to be approximately 50-times more effective in stimulating the temperature of brown adipose tissue than (+/-)baclofen. The results indicate that activation of central GABAB receptors stimulates the activity and hence metabolic rate of brown adipose tissue. However, activation of the GABAA receptors opposes the effects of GABAB stimulation on the thermogenesis of brown fat.

  2. Flow Cytometric Isolation and Differentiation of Adipogenic Progenitor Cells into Brown and Brite/Beige Adipocytes.

    PubMed

    Steinbring, Jochen; Graja, Antonia; Jank, Anne-Marie; Schulz, Tim J

    2017-01-01

    Aside from mature adipocytes, adipose tissue harbors several distinct cell populations including immune cells, endothelial cells, and adipogenic progenitor cells (AdPCs). AdPCs represent the reservoir of regenerative cells that replenishes adipocytes during normal cellular turnover and during times of increased demand for triglyceride-storage capacity. The worldwide increase in pathologies associated with the metabolic syndrome, such as obesity and type-2 diabetes, has heightened public and scientific interest in adipose tissues and the cell biological processes of adipose tissue formation and function. Two distinct types of fat cells are known: White and brown adipocytes. Especially brown adipose tissue (BAT) has received considerable attention due to its unique capacity for thermogenic energy expenditure and potential role in the treatment of adiposity. Accordingly, the cold-induced conversion of white into brown-like adipocytes has become a feasible approach in humans and a study-subject in rodents to better understand the underlying molecular processes. Fluorescence-activated cell sorting (FACS) provides a method to isolate AdPCs and other cell populations from adipose tissue by using antibodies detecting unique surface markers. We here describe an approach to isolate cells committed to the adipogenic lineage and summarize established protocols to differentiate FACS-purified primary AdPCs into UCP1-expressing brown adipocytes under in vitro conditions.

  3. Brown but not white adipose cells synthesize omega-3 docosahexaenoic acid in culture.

    PubMed

    Qin, Xia; Park, Hui Gyu; Zhang, Ji Yao; Lawrence, Peter; Liu, Guowen; Subramanian, Nivetha; Kothapalli, Kumar S D; Brenna, J Thomas

    2016-01-01

    Adipose tissue is a complex endocrine organ which coordinates several crucial biological functions including fatty acid metabolism, glucose metabolism, energy homeostasis, and immune function. Brown adipose tissue (BAT) is most abundant in young infants during the brain growth spurt when demands for omega-3 docosahexaenoic acid (DHA, 22:6n-3) is greatest for brain structure. Our aim was to characterize relative biosynthesis of omega-3 long chain polyunsaturated fatty acids (LCPUFA) from precursors in cultured white (WAT) and brown (BAT) cells and study relevant gene expression. Mouse WAT and BAT cells were grown in regular DMEM media to confluence, and differentiation was induced. At days 0 and 8 cells were treated with albumin bound d5-18:3n-3 (d5-ALA) and analyzed 24h later. d5-ALA increased cellular eicosapentaenoic acid (EPA, 20:5n-3) and docosapentaenoic acid (DPA, 22:5n-3) in undifferentiated BAT cells, whereas differentiated BAT cells accumulated 20:4n-3, EPA and DPA. DHA as a fraction of total omega-3 LCPUFA was greatest in differentiated BAT cells compared to undifferentiated cells. Undifferentiated WAT cells accumulated EPA, whereas differentiated cells accumulated DPA. WAT accumulated trace newly synthesized DHA. Zic1 a classical brown marker and Prdm16 a key driver of brown fat cell fate are expressed only in BAT cells. Ppargc1a is 15 fold higher in differentiated BAT cells. We conclude that in differentiated adipose cells accumulating fat, BAT cells but not WAT cells synthesize DHA, supporting the hypothesis that BAT is a net producer of DHA.

  4. Activated Type 2 Innate Lymphoid Cells regulate Beige Fat Biogenesis

    PubMed Central

    Lee, Min-Woo; Odegaard, Justin I.; Mukundan, Lata; Qiu, Yifu; Molofsky, Ari B.; Nussbaum, Jesse C.; Yun, Karen; Locksley, Richard M.; Chawla, Ajay

    2014-01-01

    SUMMARY Type 2 innate lymphoid cells (ILC2s), an innate source of the type 2 cytokines interleukin (IL)-5 and -13, participate in the maintenance of tissue homeostasis. Although type 2 immunity is critically important for mediating metabolic adaptations to environmental cold, the functions of ILC2s in beige or brown fat development are poorly defined. We report here that activation of ILC2s by IL-33 is sufficient to promote the growth of functional beige fat in thermoneutral mice. Mechanistically, ILC2 activation results in the proliferation of bipotential adipocyte precursors (APs) and their subsequent commitment to the beige fat lineage. Loss- and gain-of-function studies reveal that ILC2-and eosinophil-derived type 2 cytokines stimulate signaling via the IL-4Rα in PDGFRα+ APs to promote beige fat biogenesis. Together, our results highlight a critical role for ILC2s and type 2 cytokines in the regulation of adipocyte precursor numbers and fate, and as a consequence, adipose tissue homeostasis. PMID:25543153

  5. PRDM16 enhances nuclear receptor-dependent transcription of the brown fat-specific Ucp1 gene through interactions with Mediator subunit MED1

    PubMed Central

    Iida, Satoshi; Chen, Wei; Nakadai, Tomoyoshi; Ohkuma, Yoshiaki

    2015-01-01

    PR domain-containing 16 (PRDM16) induces expression of brown fat-specific genes in brown and beige adipocytes, although the underlying transcription-related mechanisms remain largely unknown. Here, in vitro studies show that PRDM16, through its zinc finger domains, directly interacts with the MED1 subunit of the Mediator complex, is recruited to the enhancer of the brown fat-specific uncoupling protein 1 (Ucp1) gene through this interaction, and enhances thyroid hormone receptor (TR)-driven transcription in a biochemically defined system in a Mediator-dependent manner, thus providing a direct link to the general transcription machinery. Complementary cell-based studies show that upon forskolin treatment, PRDM16 induces Ucp1 expression in undifferentiated murine embryonic fibroblasts, that this induction depends on MED1 and TR, and, consistent with a direct effect, that PRDM16 is recruited to the Ucp1 enhancer. Related studies have defined MED1 and PRDM16 interaction domains important for Ucp1 versus Ppargc1a induction by PRDM16. These results reveal novel mechanisms for PRDM16 function through the Mediator complex. PMID:25644605

  6. Brown Algae Polyphenol, a Prolyl Isomerase Pin1 Inhibitor, Prevents Obesity by Inhibiting the Differentiation of Stem Cells into Adipocytes

    PubMed Central

    Suzuki, Atsuko; Saeki, Toshiyuki; Ikuji, Hiroko; Uchida, Chiyoko; Uchida, Takafumi

    2016-01-01

    Background While screening for an inhibitor of the peptidyl prolyl cis/trans isomerase, Pin1, we came across a brown algae polyphenol that blocks the differentiation of fibroblasts into adipocytes. However, its effectiveness on the accumulation of fat in the body has never been studied. Methodology/Principal Findings Oral administration of brown algae polyphenol to mice fed with a high fat diet, suppressed the increase in fat volume to a level observed in mice fed with a normal diet. We speculate that Pin1 might be required for the differentiation of stem cell to adipocytes. We established wild type (WT) and Pin1-/- (Pin1-KO) adipose-derived mesenchymal stem cell (ASC) lines and found that WT ASCs differentiate to adipocytes but Pin1-KO ASCs do not. Conclusion and Significance Oral administration of brown algae polyphenol, a Pin1 inhibitor, reduced fat buildup in mice. We showed that Pin1 is required for the differentiation of stem cells into adipocytes. We propose that oral intake of brown algae polyphenol is useful for the treatment of obesity. PMID:28036348

  7. Anti-obesity effects of Arctii Fructus (Arctium lappa) in white/brown adipocytes and high-fat diet-induced obese mice.

    PubMed

    Han, Yo-Han; Kee, Ji-Ye; Kim, Dae-Seung; Park, Jinbong; Jeong, Mi-Young; Mun, Jung-Geon; Park, Sung-Joo; Lee, Jong-Hyun; Um, Jae-Young; Hong, Seung-Heon

    2016-12-07

    Arctii Fructus is traditionally used in oriental pharmacies as an anti-inflammatory medicine. Although several studies have shown its anti-inflammatory effects, there have been no reports on its use in obesity related studies. In this study, the anti-obesity effect of Arctii Fructus was investigated in high-fat diet (HFD)-induced obese mice, and the effect was confirmed in white and primary cultured brown adipocytes. Arctii Fructus inhibited weight gain and reduced the mass of white adipose tissue in HFD-induced obese mice. Serum levels of triglyceride and LDL-cholesterol were reduced, and HDL-cholesterol was increased in the Arctii Fructus treated group. In 3T3-L1 cells, a water extract (WAF) and 70% EtOH extract (EtAF) of Arctii Fructus significantly inhibited adipogenesis and suppressed the expression of proliferator-activated receptor gamma and CCAAT/enhancer-binding protein alpha. In particular, EtAF activated the phosphorylation of AMP-activated protein kinase. On the other hand, uncoupling protein 1 and peroxisome proliferator-activated receptor gamma coactivator 1-alpha, known as brown adipocytes specific genes, were increased in primary cultured brown adipocytes by WAF and EtAF. This study shows that Arctii Fructus prevents the development of obesity through the inhibition of white adipocyte differentiation and activation of brown adipocyte differentiation which suggests that Arctii Fructus could be an effective therapeutic for treating or preventing obesity.

  8. Bardoxolone Methyl Prevents Fat Deposition and Inflammation in Brown Adipose Tissue and Enhances Sympathetic Activity in Mice Fed a High-Fat Diet

    PubMed Central

    Dinh, Chi H. L.; Szabo, Alexander; Yu, Yinghua; Camer, Danielle; Zhang, Qingsheng; Wang, Hongqin; Huang, Xu-Feng

    2015-01-01

    Obesity results in changes in brown adipose tissue (BAT) morphology, leading to fat deposition, inflammation, and alterations in sympathetic nerve activity. Bardoxolone methyl (BARD) has been extensively studied for the treatment of chronic diseases. We present for the first time the effects of oral BARD treatment on BAT morphology and associated changes in the brainstem. Three groups (n = 7) of C57BL/6J mice were fed either a high-fat diet (HFD), a high-fat diet supplemented with BARD (HFD/BARD), or a low-fat diet (LFD) for 21 weeks. BARD was administered daily in drinking water. Interscapular BAT, and ventrolateral medulla (VLM) and dorsal vagal complex (DVC) in the brainstem, were collected for analysis by histology, immunohistochemistry and Western blot. BARD prevented fat deposition in BAT, demonstrated by the decreased accumulation of lipid droplets. When administered BARD, HFD mice had lower numbers of F4/80 and CD11c macrophages in the BAT with an increased proportion of CD206 macrophages, suggesting an anti-inflammatory effect. BARD increased phosphorylation of tyrosine hydroxylase in BAT and VLM. In the VLM, BARD increased energy expenditure proteins, including beta 3-adrenergic receptor (β3-AR) and peroxisome proliferator-activated receptor gamma coactivator 1-alpha (PGC-1α). Overall, oral BARD prevented fat deposition and inflammation in BAT, and stimulated sympathetic nerve activity. PMID:26066016

  9. Cardiac natriuretic peptides act via p38 MAPK to induce the brown fat thermogenic program in mouse and human adipocytes

    PubMed Central

    Bordicchia, Marica; Liu, Dianxin; Amri, Ez-Zoubir; Ailhaud, Gerard; Dessì-Fulgheri, Paolo; Zhang, Chaoying; Takahashi, Nobuyuki; Sarzani, Riccardo; Collins, Sheila

    2012-01-01

    The ability of mammals to resist body fat accumulation is linked to their ability to expand the number and activity of “brown adipocytes” within white fat depots. Activation of β-adrenergic receptors (β-ARs) can induce a functional “brown-like” adipocyte phenotype. As cardiac natriuretic peptides (NPs) and β-AR agonists are similarly potent at stimulating lipolysis in human adipocytes, we investigated whether NPs could induce human and mouse adipocytes to acquire brown adipocyte features, including a capacity for thermogenic energy expenditure mediated by uncoupling protein 1 (UCP1). In human adipocytes, atrial NP (ANP) and ventricular NP (BNP) activated PPARγ coactivator-1α (PGC-1α) and UCP1 expression, induced mitochondriogenesis, and increased uncoupled and total respiration. At low concentrations, ANP and β-AR agonists additively enhanced expression of brown fat and mitochondrial markers in a p38 MAPK–dependent manner. Mice exposed to cold temperatures had increased levels of circulating NPs as well as higher expression of NP signaling receptor and lower expression of the NP clearance receptor (Nprc) in brown adipose tissue (BAT) and white adipose tissue (WAT). NPR-C–/– mice had markedly smaller WAT and BAT depots but higher expression of thermogenic genes such as Ucp1. Infusion of BNP into mice robustly increased Ucp1 and Pgc-1α expression in WAT and BAT, with corresponding elevation of respiration and energy expenditure. These results suggest that NPs promote “browning” of white adipocytes to increase energy expenditure, defining the heart as a central regulator of adipose tissue biology. PMID:22307324

  10. GQ-16, a TZD-Derived Partial PPARγ Agonist, Induces the Expression of Thermogenesis-Related Genes in Brown Fat and Visceral White Fat and Decreases Visceral Adiposity in Obese and Hyperglycemic Mice

    PubMed Central

    Coelho, Michella S.; de Lima, Caroline L.; Royer, Carine; Silva, Janaina B.; Oliveira, Fernanda C. B.; Christ, Camila G.; Pereira, Sidney A.; Bao, Sonia N.; Lima, Maria C. A.; Pitta, Marina G. R.; Pitta, Ivan R.; Neves, Francisco A. R.; Amato, Angélica A.

    2016-01-01

    Background Beige adipocytes comprise a unique thermogenic cell type in the white adipose tissue (WAT) of rodents and humans, and play a critical role in energy homeostasis. In this scenario, recruitment of beige cells has been an important focus of interest for the development of novel therapeutic strategies to treat obesity. PPARγ activation by full agonists (thiazolidinediones, TZDs) drives the appearance of beige cells, a process so-called browning of WAT. However, this does not translate into increased energy expenditure, and TZDs are associated with weight gain. Partial PPARγ agonists, on the other hand, do not induce weight gain, but have not been shown to drive WAT browning. The present study was designed to investigate the effects of GQ-16 on BAT and on browning of WAT in obese mice. Methods Male Swiss mice with obesity and hyperglycemia induced by high fat diet were treated with vehicle, rosiglitazone (4 mg/kg/d) or the TZD-derived partial PPARγ agonist GQ-16 (40 mg/kg/d) for 14 days. Fasting blood glucose, aspartate aminotransferase, alanine aminotransferase and lipid profile were measured. WAT and brown adipose tissue (BAT) depots were excised for determination of adiposity, relative expression of Ucp-1, Cidea, Prdm16, Cd40 and Tmem26 by RT-qPCR, histological analysis, and UCP-1 protein expression analysis by immunohistochemistry. Liver samples were also removed for histological analysis and determination of hepatic triglyceride content. Results GQ-16 treatment reduced high fat diet-induced weight gain in mice despite increasing energy intake. This was accompanied by reduced epididymal fat mass, reduced liver triglyceride content, morphological signs of increased BAT activity, increased expression of thermogenesis-related genes in interscapular BAT and epididymal WAT, and increased UCP-1 protein expression in interscapular BAT and in epididymal and inguinal WAT. Conclusion This study suggests for the first time that a partial PPARγ agonist may

  11. Lower weight gain and hepatic lipid content in hamsters fed high fat diets supplemented with white rice protein, brown rice protein, and soy protein and their hydrolysates

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The physiological effects of the hydrolysates from white rice, brown rice, and soy isolate were compared to the original protein source. White rice, brown rice, and soy protein were hydrolyzed with the food grade enzyme, alcalase2.4 L®. Male Syrian hamsters were fed high-fat diets containing eithe...

  12. Current challenges in dedifferentiated fat cells research.

    PubMed

    Shah, Mickey; George, Richard L; Evancho-Chapman, M Michelle; Zhang, Ge

    2016-07-02

    Dedifferentiated fat cells show great promises as a novel cell source for stem cell research. It has many advantages when used for cell-based therapeutics including abundance, pluripotency, and safety. However, there are many obstacles researchers need to overcome to make the next big move in DFAT cells research. In this review, we summarize the current main challenges in DFAT cells research including cell culture purity, phenotypic properties, and dedifferentiation mechanisms. The common methods to produce DFAT cells as well as the cell purity issue during DFAT cell production have been introduced. Current approaches to improve DFAT cell purity have been discussed. The phenotypic profile of DFAT cells have been listed and compared with other stem cells. Further studies on elucidating the underlying dedifferentiation mechanisms will dramatically advance DFAT cell research.

  13. Identification of brown fat and mechanisms for energy balance in the marsupial, Sminthopsis crassicaudata.

    PubMed

    Hope, P J; Pyle, D; Daniels, C B; Chapman, I; Horowitz, M; Morley, J E; Trayhurn, P; Kumaratilake, J; Wittert, G

    1997-07-01

    The presence of brown adipose tissue (BAT) in marsupials is controversial because attempts to identify mitochondrial uncoupling protein (UCP) have been unsuccessful. Sminthopsis crassicaudata is a small nocturnal marsupial with an interscapular pad of adipose tissue. Electron microscopy revealed this tissue to have characteristics typical of BAT. GDP binding and UCP detection by immunoblot confirmed BAT. Expression of UCP was increased by cold exposure. When animals were placed from 28 to 15 degrees C, body temperature (Tb) decreased by 1.7 degrees C within 30 min and a further 1.0 degree C by 90 min (P < 0.001) before stabilizing at these lower levels. When animals were returned to 28 degrees C, Tb increased within 30 min (P < 0.001) and returned to basal by 120 min. When animals were maintained at 15 degrees C with ad libitum food for 12 days, Tb (P < 0.05), tail width (P < 0.04), and O2 consumption (P < 0.01) all decreased. The respiratory quotient increased (P < 0.001), indicating a change from fat to carbohydrate utilization. Food intake was unchanged, and body weight increased on day 1 (P < 0.01) before returning to baseline on day 3, remaining stable thereafter. These data suggest that although BAT is present in the marsupial S. crassicaudata, it may not be necessary for thermogenesis, at least in the short term. S. crassicaudata utilizes a plasticity in Tb and a change in substrate utilization to maintain energy balance and body composition without the need for an increase in metabolic rate or food consumption and without the need for torpor.

  14. Effects of the Polysaccharide from the Sporophyll of Brown Alga Undaria Pinnatifida on Serum Lipid Profile and Fat Tissue Accumulation in Rats Fed a High-Fat Diet.

    PubMed

    Kim, Byoung-Mok; Park, Jae-Ho; Kim, Dong-Soo; Kim, Young-Myung; Jun, Joon-Young; Jeong, In-Hak; Chi, Young-Min

    2016-07-01

    We investigated the effects of the polysaccharide from the sporophyll of a selected brown alga Undaria pinnatifida on serum lipid profile, fat tissue accumulation, and gastrointestinal transit time in rats fed a high-fat diet. The algal polysaccharide (AP) was prepared by the treatment of multiple cellulase-producing fungi Trichoderma reesei and obtained from the sporophyll with a yield of 38.7% (dry basis). The AP was mostly composed of alginate and fucoidan (up to 89%) in a ratio of 3.75:1. The AP was added to the high-fat diet in concentrations of 0.6% and 1.7% and was given to male Sprague-Dawley rats (5-wk-old) for 5 wk. The 1.7% AP addition notably reduced body weight gain and fat tissue accumulation, and it improved the serum lipid profile, including triglycerides, total cholesterol, and very low-density lipoprotein-cholesterol. The effects were associated with increased feces weight and shortened gastrointestinal transit time. In addition, the lipid peroxidation of the liver was decreased in both groups.

  15. Gene expression profiles reveal effect of a high-fat diet on the development of white and brown adipose tissues.

    PubMed

    Kim, Hyeng-Soo; Ryoo, Zae Young; Choi, Sang Un; Lee, Sanggyu

    2015-07-01

    Because of the recent discovery of brown adipose tissues tissue in adult humans, brown adipose tissues have garnered additional attention. Many studies have attempted to transform the precursor cells within the white adipocyte cultures to Brite (brown-in-white) cells by using genomic modification or pharmacological activation in order to determine the therapeutic effect of obesity. However, genome-scale analysis of the genetic factors governing the development of white and brown adipose tissues remains incomplete. In order to identify the key genes that regulate the development of white and brown adipose tissues in mice, a transcriptome analysis was performed on the adipose tissues. Network analysis of differentially expressed genes indicated that Trim30 and Ucp3 play pivotal roles in energy balance and glucose homeostasis. In addition, it was discovered that identical biological processes and pathways in the white and brown adipose tissues might be regulated by different genes. Trim30 and Ucp3 might be used as genetic markers to precisely represent the stage of obesity during the early and late stages of adipose tissue development, respectively. These results may provide a stepping-stone for future obesity-related studies.

  16. Activation of β3-adrenoceptors increases in vivo free fatty acid uptake and utilization in brown but not white fat depots in high-fat-fed rats

    PubMed Central

    Warner, Amy; Kjellstedt, Ann; Carreras, Alba; Böttcher, Gerhard; Peng, Xiao-Rong; Seale, Patrick; Oakes, Nicholas

    2016-01-01

    Activation of brown adipose tissue (BAT) and browning of white adipose tissue (WAT) present potential new therapies for obesity and type 2 diabetes. Here, we examined the effects of β3-adrenergic stimulation on tissue-specific uptake and storage of free fatty acids (FFA) and its implications for whole body FFA metabolism in diet-induced obese rats using a multi-radiotracer technique. Male Wistar rats were high fat-fed for 12 wk and administered β3-agonist CL316,243 (CL, 1 mg·kg−1·day−1) or saline via osmotic minipumps during the last 3 wk. The rats were then fasted and acutely infused with a tracer mixture ([14C]palmitate and the partially metabolized R-[3H]bromopalmitate) under anesthesia. CL infusion decreased body weight gain and fasting plasma glucose levels. While core body temperature was unaffected, infrared thermography showed an increase in tail heat dissipation following CL infusion. Interestingly, CL markedly increased both FFA storage and utilization in interscapular and perirenal BAT, whereas the flux of FFA to skeletal muscle was decreased. In this rat model of obesity, only sporadic populations of beige adipocytes were detected in the epididymal WAT depot of CL-infused rats, and there was no change in FFA uptake or utilization in WAT following CL infusion. In summary, β3-agonism robustly increased FFA flux to BAT coupled with enhanced utilization. Increased BAT activation most likely drove the increased tail heat dissipation to maintain thermostasis. Our results emphasize the quantitative role of brown fat as the functional target of β3-agonism in obesity. PMID:27780820

  17. Chronic activation of pattern recognition receptors suppresses brown adipogenesis of multipotent mesodermal stem cells and brown pre-adipocytes.

    PubMed

    Bae, Jiyoung; Chen, Jiangang; Zhao, Ling

    2015-06-01

    Brown adipose tissue (BAT) holds promise to combat obesity through energy-spending, non-shivering thermogenesis. Understanding of regulation of BAT development can lead to novel strategies to increase BAT mass and function for obesity treatment and prevention. Here, we report the effects of chronic activation of PRR on brown adipogenesis of multipotent mesodermal stem C3H10T1/2 cells and immortalized brown pre-adipocytes from the classical interscapular BAT of mice. Activation of NOD1, TLR4, or TLR2 by their respective synthetic ligand suppressed brown marker gene expression and lipid accumulation during differentiation of brown-like adipocytes of C3H10T1/2. Activation of the PRR only during the commitment was sufficient to suppress the differentiation. PRR activation suppressed PGC-1α mRNA, but induced PRDM16 mRNA at the commitment. Consistently, PRR activation suppressed the differentiation of immortalized brown pre-adipocytes. Activation of PRR induced NF-κB activation in both cells, which correlated with their abilities to suppress PPARγ transactivation, a critical event for brown adipogenesis. Taken together, our results demonstrate that chronic PRR activation suppressed brown adipogenesis of multipotent mesodermal stem cells and brown pre-adipocytes, possibly through suppression of PPARγ transactivation. The results suggest that anti- inflammatory therapies targeting PRRs may be beneficial for the BAT development.

  18. An ERβ agonist induces browning of subcutaneous abdominal fat pad in obese female mice

    PubMed Central

    Miao, Yi-fei; Su, Wen; Dai, Yu-bing; Wu, Wan-fu; Huang, Bo; Barros, Rodrigo P. A.; Nguyen, Hao; Maneix, Laure; Guan, You-fei; Warner, Margaret; Gustafsson, Jan-Åke

    2016-01-01

    Estrogen, via estrogen receptor alpha (ERα), exerts several beneficial effects on metabolism and energy homeostasis by controlling size, enzymatic activity and hormonal content of adipose tissue. The actions of estrogen on sympathetic ganglia, which are key players in the browning process, are less well known. In the present study we show that ERβ influences browning of subcutaneous adipose tissue (SAT) via its actions both on sympathetic ganglia and on the SAT itself. A 3-day-treatment with a selective ERβ agonist, LY3201, induced browning of SAT in 1-year-old obese WT and ERα−/− female mice. Browning was associated with increased expression of ERβ in the nuclei of neurons in the sympathetic ganglia, increase in tyrosine hydroxylase in both nerve terminals in the SAT and sympathetic ganglia neurons and an increase of β3-adrenoceptor in the SAT. LY3201 had no effect on browning in young female or male mice. In the case of young females browning was already maximal while in males there was very little expression of ERβ in the SAT and very little expression of the β3-adrenoceptor. The increase in both sympathetic tone and responsiveness of adipocytes to catecholamines reveals a novel role for ERβ in controlling browning of adipose tissue. PMID:27922125

  19. NT-PGC-1α activation attenuates high-fat diet-induced obesity by enhancing brown fat thermogenesis and adipose tissue oxidative metabolism.

    PubMed

    Jun, Hee-Jin; Joshi, Yagini; Patil, Yuvraj; Noland, Robert C; Chang, Ji Suk

    2014-11-01

    The transcriptional coactivator peroxisome proliferator-activated receptor γ coactivator (PGC)-1α and its splice variant N terminal (NT)-PGC-1α regulate adaptive thermogenesis by transcriptional induction of thermogenic and mitochondrial genes involved in energy metabolism. We previously reported that full-length PGC-1α (FL-PGC-1α) is dispensable for cold-induced nonshivering thermogenesis in FL-PGC-1α(-/-) mice, since a slightly shorter but functionally equivalent form of NT-PGC-1α (NT-PGC-1α(254)) fully compensates for the loss of FL-PGC-1α in brown and white adipose tissue. In the current study, we challenged FL-PGC-1α(-/-) mice with a high-fat diet (HFD) to investigate the effects of diet-induced thermogenesis on HFD-induced obesity. Despite a large decrease in locomotor activity, FL-PGC-1α(-/-) mice exhibited the surprising ability to attenuate HFD-induced obesity. Reduced fat mass in FL-PGC-1α(-/-) mice was closely associated with an increase in body temperature, energy expenditure, and whole-body fatty acid oxidation (FAO). Mechanistically, FL-PGC-1α(-/-) brown adipose tissue had an increased capacity to oxidize fatty acids and dissipate energy as heat, in accordance with upregulation of thermogenic genes UCP1 and DIO2. Furthermore, augmented expression of FAO and lipolytic genes in FL-PGC-1α(-/-) white adipose tissue was highly correlated with decreased fat storage in adipose tissue. Collectively, our data highlight a protective effect of NT-PGC-1α on diet-induced obesity by enhancing diet-induced thermogenesis and FAO.

  20. Age-related decrease in cold-activated brown adipose tissue and accumulation of body fat in healthy humans.

    PubMed

    Yoneshiro, Takeshi; Aita, Sayuri; Matsushita, Mami; Okamatsu-Ogura, Yuko; Kameya, Toshimitsu; Kawai, Yuko; Miyagawa, Masao; Tsujisaki, Masayuki; Saito, Masayuki

    2011-09-01

    Brown adipose tissue (BAT) can be identified by (18)F-fluorodeoxyglucose (FDG)-positron emission tomography (PET) combined with X-ray computed tomography (CT) in adult humans. The objective of this study was to clarify the relationship between BAT and adiposity in healthy adult humans, particularly to test the idea that decreased BAT activity may be associated with body fat accumulation with age. One hundred and sixty-two healthy volunteers aged 20-73 years (103 males and 59 females) underwent FDG-PET/CT after 2-h cold exposure at 19 °C with light clothing. Cold-activated BAT was detected in 41% of the subjects (BAT-positive). Compared with the BAT-negative group, the BAT-positive group was younger (P < 0.01) and showed a lower BMI (P < 0.01), body fat content (P < 0.01), and abdominal fat (P < 0.01). The incidence of cold-activated BAT decreased with age (P < 0.01), being more than 50% in the twenties, but less than 10% in the fifties and sixties. The adiposity-related parameters showed some sex differences, but increased with age in the BAT-negative group (P < 0.01), while they remained unchanged from the twenties to forties in the BAT-positive group, in both sexes. These results suggest that decreased BAT activity may be associated with accumulation of body fat with age.

  1. 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

  2. Cold exposure induces the acquisition of brown adipocyte gene expression profiles in cattle inguinal fat normalized with a new set of reference genes for qRT-PCR.

    PubMed

    Cao, K X; Hao, D; Wang, J; Peng, W W; Yan, Y J; Cao, H X; Sun, F; Chen, H

    2017-02-24

    The last few years have seen great advances in our understanding of browning in white adipose tissue (WAT) where white adipocytes take on characteristics of brown adipocytes. At present, the economic significance of browning for animal husbandry is beginning to be realized with the emerging evidence that browning affects body weight not only in human and rodent but in farm animals. Quantitative RT-PCR provides a quick and sensitive way to preliminary determine browning of WAT. However, there have been no established condition specific reference genes for browning of cattle WAT. As the results showed, the most two stable reference genes for diet treatment were Wdr33 (M=0.38) and Hdac3 (M=0.43), while the most three internal controls for temperature treatment were Hdac3 (M=0.28), Wdr33 (M=0.32), and Hprt1 (M=0.39) among the ten candidates. The mRNA relative expression levels of selective marker genes were normalized by normalization factor (geometric mean of control genes quantities). Cold exposure rather than high energy diet induced transcript elevations of brite specific markers (Cited1, Tbx1), thermoregulatory markers (brown and beige versus white markers, i.e., Cidea, Cox7a1, Ucp1), mitochondrial biogenesis markers (Nrf1, Nrf2, Tfam), and transcription regulators (brown and beige versus white markers, i.e., Pgc1α) (P<0.05) in cattle inguinal fat (iWAT). Quantitative RT-PCR is a preliminary study for WAT browning. In conclusion, cattle inguinal fat acquired brown adipocyte gene expression features upon cold acclimation with prerequisite identification of stable reference genes.

  3. Biodegradable Polymeric Microsphere-Based Drug Delivery for Inductive Browning of Fat

    PubMed Central

    Jiang, Chunhui; Kuang, Liangju; Merkel, Madeline P.; Yue, Feng; Cano-Vega, Mario Alberto; Narayanan, Naagarajan; Kuang, Shihuan; Deng, Meng

    2015-01-01

    Brown and beige adipocytes are potent therapeutic agents to increase energy expenditure and reduce risks of obesity and its affiliated metabolic symptoms. One strategy to increase beige adipocyte content is through inhibition of the evolutionarily conserved Notch signaling pathway. However, systemic delivery of Notch inhibitors is associated with off-target effects and multiple dosages of application further faces technical and translational challenges. Here, we report the development of a biodegradable polymeric microsphere-based drug delivery system for sustained, local release of a Notch inhibitor, DBZ. The microsphere-based delivery system was fabricated and optimized using an emulsion/solvent evaporation technique to encapsulate DBZ into poly(lactide-co-glycolide) (PLGA), a commonly used biodegradable polymer for controlled drug release. Release studies revealed the ability of PLGA microspheres to release DBZ in a sustained manner. Co-culture of white adipocytes with and without DBZ-loaded PLGA microspheres demonstrated that the released DBZ retained its bioactivity, and effectively inhibited Notch and promoted browning of white adipocytes. Injection of these DBZ-loaded PLGA microspheres into mouse inguinal white adipose tissue depots resulted in browning in vivo. Our results provide the encouraging proof-of-principle evidence for the application of biodegradable polymers as a controlled release platform for delivery of browning factors, and pave the way for development of new translational therapeutic strategies for treatment of obesity. PMID:26617571

  4. Mechanisms and effective control of physiological browning phenomena in plant cell cultures.

    PubMed

    Dong, Yan-Shan; Fu, Chun-Hua; Su, Peng; Xu, Xiang-Ping; Yuan, Jie; Wang, Sheng; Zhang, Meng; Zhao, Chun-Fang; Yu, Long-Jiang

    2016-01-01

    Browning phenomena are ubiquitous in plant cell cultures that severely hamper scientific research and widespread application of plant cell cultures. Up to now, this problem still has not been well controlled due to the unclear browning mechanisms in plant cell cultures. In this paper, the mechanisms were investigated using two typical materials with severe browning phenomena, Taxus chinensis and Glycyrrhiza inflata cells. Our results illustrated that the browning is attributed to a physiological enzymatic reaction, and phenolic biosynthesis regulated by sugar plays a decisive role in the browning. Furthermore, to confirm the specific compounds which participate in the enzymatic browning reaction, transcriptional profile and metabolites of T. chinensis cells, and UV scanning and high-performance liquid chromatography-mass spectrometry (HPLC-MS) profile of the browning compounds extracted from the brown-turned medium were analyzed, flavonoids derived from phenylpropanoid pathway were found to be the main compounds, and myricetin and quercetin were deduced to be the main substrates of the browning reaction. Inhibition of flavonoid biosynthesis can prevent the browning occurrence, and the browning is effectively controlled via blocking flavonoid biosynthesis by gibberellic acid (GA3 ) as an inhibitor, which further confirms that flavonoids mainly contribute to the browning. On the basis above, a model elucidating enzymatic browning mechanisms in plant cell cultures was put forward, and effective control approaches were presented.

  5. Water-fat MRI in a hibernator reveals seasonal growth of white and brown adipose tissue without cold exposure.

    PubMed

    MacCannell, Amanda; Sinclair, Kevin; Friesen-Waldner, Lannette; McKenzie, Charles A; Staples, James F

    2017-03-21

    Obligate hibernators, such as ground squirrels, display circannual patterns which persist even under constant laboratory conditions, suggesting that they are regulated by endogenous rhythms. Brown adipose tissue (BAT) is important for thermogenesis during periodic arousals from hibernation when core body temperature rises spontaneously from 5 to 37 °C. In most small eutherians BAT growth requires several weeks of cold exposure. We hypothesized that in the thirteen-lined ground squirrel (Ictidomys tridecemlineatus), a hibernator, BAT growth is regulated, in part, by an endogenous rhythm and we predicted that this growth would precede the hibernation season without cold exposure. We tested this prediction using repeated water-fat magnetic resonance imaging over a year, including the hibernation season. Thoracic BAT depots increased in volume from spring through autumn even though animals were housed at ~22 °C. Subsequent cold exposure (5 °C) enlarged the thoracic BAT further. The fat fraction of this tissue fell significantly during the period of peak growth, indicating relative increases in non-triglyceride components, perhaps mitochondria or vasculature. We also found that the proportion of the body consisting of white adipose tissue (WAT) increased steadily from spring through autumn, and fell throughout hibernation, mirroring changes in body mass. Unlike BAT, WAT fat fractions remained constant (near 90%) throughout the year. Future studies will evaluate the significance of photoperiod and cold exposure on the growth of these tissues. We also found tissue with a fat fraction characteristic of BAT in the head near the eyes, a potentially novel discovery that requires further confirmation.

  6. The Molecular Signature of HIV-1-Associated Lipomatosis Reveals Differential Involvement of Brown and Beige/Brite Adipocyte Cell Lineages.

    PubMed

    Cereijo, Rubén; Gallego-Escuredo, José Miguel; Moure, Ricardo; Villarroya, Joan; Domingo, Joan Carles; Fontdevila, Joan; Martínez, Esteban; Gutiérrez, Maria del Mar; Mateo, María Gracia; Giralt, Marta; Domingo, Pere; Villarroya, Francesc

    2015-01-01

    Highly active antiretroviral therapy has remarkably improved quality of life of HIV-1-infected patients. However, this treatment has been associated with the so-called lipodystrophic syndrome, which conveys a number of adverse metabolic effects and morphological alterations. Among them, lipoatrophy of subcutaneous fat in certain anatomical areas and hypertrophy of visceral depots are the most common. Less frequently, lipomatous enlargements of subcutaneous fat at distinct anatomic areas occur. Lipomatous adipose tissue in the dorso-cervical area ("buffalo hump") has been associated with a partial white-to-brown phenotype transition and with increased cell proliferation, but, to date, lipomatous enlargements arising in other parts of the body have not been characterized. In order to establish the main molecular events associated with the appearance of lipomatosis in HIV-1 patients, we analyzed biopsies of lipomatous tissue from "buffalo hump" and from other anatomical areas in patients, in comparison with healthy subcutaneous adipose tissue, using a marker gene expression approach. Both buffalo-hump and non-buffalo-hump lipomatous adipose tissues exhibited similar patterns of non-compromised adipogenesis, unaltered inflammation, non-fibrotic phenotype and proliferative activity. Shorter telomere length, prelamin A accumulation and SA-β-Gal induction, reminiscent of adipocyte senescence, were also common to both types of lipomatous tissues. Buffalo hump biopsies showed expression of marker genes of brown adipose tissue (e.g. UCP1) and, specifically, of "classical" brown adipocytes (e.g. ZIC1) but not of beige/brite adipocytes. No such brown fat-related gene expression occurred in lipomatous tissues at other anatomical sites. In conclusion, buffalo hump and other subcutaneous adipose tissue enlargements from HIV-1-infected patients share a similar lipomatous character. However, a distorted induction of white-to-"classical brown adipocyte" phenotype appears unique of

  7. Effect of High Fructose and High Fat Diets on Pulmonary Sensitivity, Motor Activity, and Body Composition of Brown Norway Rats Exposed to Ozone

    EPA Science Inventory

    Diet-induced obesity has been suggested to lead to increased susceptibility to air pollutants such as ozone (03); however, there is little experimental evidence. Thirty day old male and female Brown Norway rats were fed a normal, high-fructose or high-fat diet for 12 weeks and th...

  8. Adipose-derived regenerative cell (ADRC)-enriched fat grafting: optimal cell concentration and effects on grafted fat characteristics

    PubMed Central

    2013-01-01

    Background To overcome the absorption of traditional fat grafting, techniques for adipose-derived regenerative cell (ADRC)-enriched fat grafting are currently being adapted for practical application. The Celution®800/CRS (Cytori Therapeutics, San Diego, CA) has enabled rapid grafting of the patient’s own freshly harvested ADRCs without requiring a culturing step. However, the optimal cell concentration and the effects of ADRCs on the characteristics of grafted fat after free fat grafting remain unclear. Methods ADRCs were isolated and purified from human fat tissue using the Celution®800/CRS. Animals that received fat grafting without the addition of ADRCs were designated the control group (group A). The number of ADRCs per grafted fat volume (mL) was adjusted to 3 × 105, 1.5 × 106, and 3 × 106 cells/mL (groups B, C, and D, respectively), mixed with free fat, and transplanted as ADRC-enriched fat grafting. These mixtures were transplanted subcutaneously into BALB/C Jcl-nu/nu mice. The volume of grafted fat was determined 5 months after transplantation, and histological assessments were performed. Results ADRC-enriched fat grafting resulted in decreased fat absorption and the formation of greater numbers of new blood vessels in the grafted fat. The optimal ADRC concentration in this study was found to be 3 × 105 cells/mL (group B), with higher concentrations resulting in increased cyst and fibril formation in the grafted fat. Conclusions This study used the Celution®800/CRS for free fat grafting and demonstrated that the concentration of transplanted ADRCs affected the engraftment and quality of the grafted fat. PMID:24107489

  9. Maternal high-fat diet during lactation impairs thermogenic function of brown adipose tissue in offspring mice

    PubMed Central

    Liang, Xingwei; Yang, Qiyuan; Zhang, Lupei; Maricelli, Joseph W; Rodgers, Buel D.; Zhu, Mei-Jun; Du, Min

    2016-01-01

    Maternal obesity and high-fat diet (HFD) predisposes offspring to obesity and metabolic diseases. Due to uncoupling, brown adipose tissue (BAT) dissipates energy via heat generation, mitigating obesity and diabetes. The lactation stage is a manageable period for improving the health of offspring of obese mothers, but the impact of maternal HFD during lactation on offspring BAT function is unknown. To determine, female mice were fed either a control or HFD during lactation. At weaning, HFD offspring gained more body weight and had greater body fat mass compared to the control, and these differences maintained into adulthood, which correlated with glucose intolerance and insulin resistance in HFD offspring. Adaptive thermogenesis of BAT was impaired in HFD offspring at weaning. In adulthood, HFD offspring BAT had lower Ucp1 expression and thermogenic activity. Mechanistically, maternal HFD feeding during lactation elevated peripheral serotonin, which decreased the sensitivity of BAT to sympathetic β3-adrenergic signaling. Importantly, early postnatal metformin administration decreased serotonin concentration and ameliorated the impairment of offspring BAT due to maternal HFD. Our data suggest that attenuation of BAT thermogenic function may be a key mechanism linking maternal HFD during lactation to persisted metabolic disorder in the offspring. PMID:27686741

  10. LSD1—a pivotal epigenetic regulator of brown and beige fat differentiation and homeostasis

    PubMed Central

    Lin, Jean Z.; Farmer, Stephen R.

    2016-01-01

    In this issue of Genes & Development, Zeng and colleagues (pp. 1822–1836) identify lysine-specific demethylase 1 (LSD1) as a pivotal regulator of whole-body energy expenditure by controlling the oxidative and thermogenic activity of brown adipose tissue (BAT). They show that LSD1 interacts with PRDM16 to repress select white adipose tissue (WAT) genes but also represses hydroxysteroid 11-β-dehydrogenase 1 (HSD11B1) independently of PRDM16 to prevent production of glucocorticoids that impair BAT functions. Their study provides important insight into epigenetic mechanisms regulating the function of BAT. PMID:27601528

  11. Glycerophosphate-dependent peroxide production by brown fat mitochondria from newborn rats.

    PubMed

    Drahota, Z; Rauchova, H; Jesina, P; Vojtísková, A; Houstek, J

    2003-03-01

    Glycerophosphate (GP)-dependent, ferricyanide-induced hydrogen peroxide production was studied in brown adipose tissue mitochondria from newborn rats. Relations between the rate of hydrogen peroxide production and total amount of hydrogen peroxide produced at different GP and ferricyanide concentrations were determined. It was found that the rate of hydrogen peroxide production increases with increasing GP concentration and decreases with increasing ferricyanide concentration. Total amount of hydrogen peroxide produced increases with increasing ferricyanide concentration, however, not proportionally, and the efficiency of this process (oxygen/ferricyanide ratio) strongly declines. Data presented provide further information on the character and kinetics of hydrogen peroxide production by mammalian mitochondrial glycerophosphate dehydrogenase.

  12. Disruption of Insulin Signaling in Myf5-Expressing Progenitors Leads to Marked Paucity of Brown Fat but Normal Muscle Development

    PubMed Central

    Lynes, Matthew D.; Schulz, Tim J.; Pan, Andrew J.

    2015-01-01

    Insulin exerts pleiotropic effects on cell growth, survival, and metabolism, and its role in multiple tissues has been dissected using conditional knockout mice; however, its role in development has not been studied. Lineage tracing experiments have demonstrated that interscapular brown adipose tissue (BAT) arises from a Myf5-positive lineage shared with skeletal muscle and distinct from the majority of white adipose tissue (WAT) precursors. In this study, we sought to investigate the effects of impaired insulin signaling in the Myf5-expressing precursor cells by deleting the insulin receptor gene. Mice lacking insulin receptor in the Myf5 lineage (Myf5IRKO) have a decrease of interscapular BAT mass; however, muscle development appeared normal. Histologically, the residual BAT had decreased cell size but appeared mature and potentially functional. Expression of adipogenic inhibitors preadipocyte factor-1, Necdin, and wingless-type MMTV integration site member 10a in the residual BAT tissue was nonetheless increased compared with controls, and there was an enrichment of progenitor cells with impaired adipogenic differentiation capacity, suggesting a suppression of adipogenesis in BAT. Surprisingly, when cold challenged, Myf5IRKO mice did not show impaired thermogenesis. This resistance to cold could be attributed to an increased presence of uncoupling protein 1-positive brown adipocytes in sc WAT as well as increased expression of lipolytic activity in BAT. These data suggest a critical role of insulin signaling in the development of interscapular BAT from Myf5-positive progenitor cells, but it appears to be dispensable for muscle development. They also underscore the importance of compensatory browning of sc WAT in the absence of BAT for thermoregulation. PMID:25625589

  13. β-arrestin-1 contributes to brown fat function and directly interacts with PPARα and PPARγ

    PubMed Central

    Wang, Congcong; Zeng, Xianglu; Zhou, Zhaocai; Zhao, Jian; Pei, Gang

    2016-01-01

    The peroxisome proliferator-activated receptor (PPAR) family plays central roles in brown adipose tissue (BAT) adipogenesis and contributes to body temperature maintenance. The transcriptional activity of PPAR family has been shown to be tightly controlled by cellular signal networks. β-arrestins function as major secondary messengers of G protein-coupled receptors (GPCR) signaling by functional interactions with diverse proteins. Here, we report that β-arrestin-1 knock-out mice show enhanced cold tolerance. We found that β-arrestin-1 directly interacts with PPARα and PPARγ through a LXXXLXXXL motif, while D371 in PPARα and L311/N312/D380 in PPARγ are required for their interactions with β-arrestin-1. Further mechanistic studies showed that β-arrestin-1 promotes PPARα- but represses PPARγ-mediated transcriptional activities, providing potential regulatory pathway for BAT function. PMID:27301785

  14. Derivation of embryonic stem cells from Brown Norway rats blastocysts.

    PubMed

    Zhao, Xiaoyang; Lv, Zhuo; Liu, Lei; Wang, Liu; Tong, Man; Zhou, Qi

    2010-07-01

    Knockout Brown Norway (BN) rat could be a useful disease model for human disorders, however, a failure to derive embryonic stem (ES) cells disturbs the further development of the model. In this study, we reported a case of successful derivation of the BN rat ES cells with the derivation efficiency comparable to that of Sprague Dawley (SD) rats. The BN rat ES cells expressed the key transcription factors, and were able to form embryonic bodies (EBs) when being differentiated in vitro. After injecting the BN rat ES cells into the SD rat blastocysts, high-contribution chimeric rats were generated and could survive to their adulthood. Our success in generating pluripotent rat ES cells will benefit the generation of the knockout rats in the future.

  15. Activity of thyroxine 5' deiodinase in brown fat of lean and obese zucker rats

    SciTech Connect

    Wu, S.Y.; Fisher, D.A.; Stern, J.S.; Glick, Z.

    1986-03-01

    This study examines the possibility that the reduced brown adipose tissue (BAT) thermogenesis in the Zucker obese rat may result from a limited capacity for conversion of T/sub 4/ to T/sub 3/ in BAT, through activity of T/sub 4/ 5' deiodinase. Eighteen lean (Fa/.) and 18 age matched obese (fa/fa), about 16 weeks old, were each divided into 3 groups (n=6 per group). Group 1 and 2 were fed Purina Rat Chow and a cafeteria diet respectively for 21 days, and maintained at 22/sup 0/C+/-2. Group 3 was fed rat chow and maintained at 8/sup 0/C+/-1 for 7 days. Activity of T/sub 4/5'deiodinase was determined in vitro. T/sub 3/ was measured by a radioimmunoassay. The rate of T/sub 4/ to T/sub 3/ conversion was similar in the lean and the obese rats maintained at room temperature, whether fed rat chow or a cafeteria diet (about 40 to 50 pmol T/sub 3//scapular BAT depot, per hour). However, lean rats exposed to the cold displayed about a 5 fold increase in T/sub 4/5' deiodinase activity (p<0.0001), with only a small increase displayed by the cold exposed obese rats. Our data suggest that a reduced capacity of the brown rat to produce T/sub 3/ may account for the reduced tolerance of obese animals to cold, but it does not account for their reduced diet induced BAT thermogenesis.

  16. Proliferation and differentiation of brown adipocytes from interstitial cells during cold acclimation

    SciTech Connect

    Bukowiecki, L.J.; Geloeen, A.; Collet, A.J.

    1986-06-01

    The mechanisms of brown adipocyte proliferation and differentiation during cold acclimation (and/or adaptation to hyperphagia) have been studied by quantitative photonic radioautography. (/sup 3/H)thymidine was injected to warm-acclimated (25/sup 0/C) rats and to animals exposed to 5/sup 0/C for 2 days. Samples of interscapular brown adipose tissue were collected for quantitative analysis of mitotic frequencies at various periods of time (4 h-15 days) after the injection of (/sup 3/H)thymidine, the rats being maintained at the temperatures to which they were initially exposed. It was found that cold exposure for 2 days markedly enhanced mitotic activity in endothelial cells, interstitial cells, and brown preadipocytes rather than in fully differentiated brown adipocytes. The total tissue labeling index (percent of labeled nuclei) increased approx.70 times over control values. The authors now report that cellular labeling progressively increased in mature brown adipocytes during cold acclimation, whereas it correspondingly decreased in interstitial cells and brown preadipocytes. This indicates that the sequence of events for cellular differentiation is interstitial cells ..-->.. brown preadipocytes ..-->.. mature brown adipocytes. Remarkable, labeling frequency did not change in endothelial cells during cold acclimation demonstrating that these cells cannot be considered as progenitors of brown adipocytes. It is suggested that brown adipocyte proliferation and differentiation from interstitial cells represent the fundamental phenomena explaining the enhanced capacity of cold-acclimated and/or hyperphagic rats to respond calorigenically to catecholamines.

  17. Alpha- and beta-adrenergic mediation of changes in metabolism and Na/K exchange in rat brown fat

    PubMed Central

    1985-01-01

    Double- and triple-barreled ion-sensitive microelectrodes were used to measure changes in extracellular K+ and Na+ concentrations ([K+]o, [Na+]o) in brown fat. Redox states of different respiratory enzymes were measured simultaneously in order to correlate ion movements with metabolic activity. Trains of stimuli applied to the efferent nerves evoked two distinct increases in [K+]o. A first, small, rapid increase occurred within 10 s and accompanied a first, rapid membrane depolarization. A second, slow increase of [K+]o occurred several minutes after stimulation and accompanied a second, slow depolarization. A few seconds after stimulation onset, while the membrane was repolarizing and shifts in redox states indicated increases in lipolysis and respiration, [K+]o decreased. The [K+]o decrease was accompanied by an increase in [Na+]o, and could be partly blocked by ouabain. Phentolamine, an alpha-antagonist that blocks the first depolarization, also blocked the first, rapid [K+]o increase and part of the subsequent decrease. Propranolol, a beta-antagonist, had little effect on the first depolarization and the first increase in [K+]o, but blocked part of the subsequent [K+]o decrease and the second, slow [K+]o increase. The changes in [K+]o were almost completely abolished in the presence of both antagonists. It is concluded that brown adipocytes take up K+ and simultaneously lose Na+ in response to the interaction of noradrenaline with alpha- and beta- receptors, and this indicates a very early stimulation of the Na+ pump. PMID:2864385

  18. Numerical 3D modeling of heat transfer in human tissues for microwave radiometry monitoring of brown fat metabolism

    NASA Astrophysics Data System (ADS)

    Rodrigues, Dario B.; Maccarini, Paolo F.; Salahi, Sara; Colebeck, Erin; Topsakal, Erdem; Pereira, Pedro J. S.; Limão-Vieira, Paulo; Stauffer, Paul R.

    2013-02-01

    Background: Brown adipose tissue (BAT) plays an important role in whole body metabolism and could potentially mediate weight gain and insulin sensitivity. Although some imaging techniques allow BAT detection, there are currently no viable methods for continuous acquisition of BAT energy expenditure. We present a non-invasive technique for long term monitoring of BAT metabolism using microwave radiometry. Methods: A multilayer 3D computational model was created in HFSSTM with 1.5 mm skin, 3-10 mm subcutaneous fat, 200 mm muscle and a BAT region (2-6 cm3) located between fat and muscle. Based on this model, a log-spiral antenna was designed and optimized to maximize reception of thermal emissions from the target (BAT). The power absorption patterns calculated in HFSSTM were combined with simulated thermal distributions computed in COMSOL® to predict radiometric signal measured from an ultra-low-noise microwave radiometer. The power received by the antenna was characterized as a function of different levels of BAT metabolism under cold and noradrenergic stimulation. Results: The optimized frequency band was 1.5-2.2 GHz, with averaged antenna efficiency of 19%. The simulated power received by the radiometric antenna increased 2-9 mdBm (noradrenergic stimulus) and 4-15 mdBm (cold stimulus) corresponding to increased 15-fold BAT metabolism. Conclusions: Results demonstrated the ability to detect thermal radiation from small volumes (2-6 cm3) of BAT located up to 12 mm deep and to monitor small changes (0.5 °C) in BAT metabolism. As such, the developed miniature radiometric antenna sensor appears suitable for non-invasive long term monitoring of BAT metabolism.

  19. Thermogenin amount and activity in hamster brown fat mitochondria: effect of cold acclimation

    SciTech Connect

    Sundin, U.; Moore, G.; Nedergaard, J.; Cannon, B.

    1987-05-01

    To investigate the acclimation process in a hibernator, four different parameters of thermogenin amount and activity were investigated in brown adipose tissue mitochondria from cold-exposed and cold-acclimated Syrian hamsters. Hamsters, which are hibernators, have been considered to be primed for thermogenesis and thus not to show cold-acclimation effects, but here a significant increase in (/sup 3/H)GDP-binding capacity was observed, and this increase was paralleled by an increase in thermogenin antigen amount, as measured in an enzyme-linked immunosorbent assay. The transient nature of the effect of cold exposure on (/sup 3/H)GDP binding, characteristically observed with rat mitochondria, was not observed with hamster mitochondria, and the increase in (/sup 3/H)GDP binding occurred without a change in the dissociation constant. The increase in thermogenin amount was paralleled by an increase both in GDP-sensitive Cl/sup -/ permeability of the mitochondria and in GDP-sensitive respiration. It was established that it is the maximal activity of thermogenin that is rate limiting for thermogenesis in isolated mitochondria, provided that an optimal substrate is used (such as palmitoyl carnitine). Cold acclimation also increased the total amount of mitochondria in the tissue, leading totally to a sixfold increase in thermogenin content of the hamster. It is concluded that hamsters show the expected physiological, pharmacological, and biochemical signs of cold acclimation.

  20. Prolonged daily light exposure increases body fat mass through attenuation of brown adipose tissue activity.

    PubMed

    Kooijman, Sander; van den Berg, Rosa; Ramkisoensing, Ashna; Boon, Mariëtte R; Kuipers, Eline N; Loef, Marieke; Zonneveld, Tom C M; Lucassen, Eliane A; Sips, Hetty C M; Chatzispyrou, Iliana A; Houtkooper, Riekelt H; Meijer, Johanna H; Coomans, Claudia P; Biermasz, Nienke R; Rensen, Patrick C N

    2015-05-26

    Disruption of circadian rhythmicity is associated with obesity and related disorders, including type 2 diabetes and cardiovascular disease. Specifically, prolonged artificial light exposure associates with obesity in humans, although the underlying mechanism is unclear. Here, we report that increasing the daily hours of light exposure increases body adiposity through attenuation of brown adipose tissue (BAT) activity, a major contributor of energy expenditure. Mice exposed to a prolonged day length of 16- and 24-h light, compared with regular 12-h light, showed increased adiposity without affecting food intake or locomotor activity. Mechanistically, we demonstrated that prolonged day length decreases sympathetic input into BAT and reduces β3-adrenergic intracellular signaling. Concomitantly, prolonging day length decreased the uptake of fatty acids from triglyceride-rich lipoproteins, as well as of glucose from plasma selectively by BAT. We conclude that impaired BAT activity is an important mediator in the association between disturbed circadian rhythm and adiposity, and anticipate that activation of BAT may overcome the adverse metabolic consequences of disturbed circadian rhythmicity.

  1. Food Entrainment of Circadian Gene Expression Altered in PPARα−/− Brown Fat and Heart

    PubMed Central

    Goh, Brian C.; Wu, Xiying; Evans, Ann E.; Johnson, Meagan L.; Hill, Molly R.; Gimble, Jeffrey M.

    2008-01-01

    The circadian clock is subject to food entrainment. Since PPARα exhibits a circadian expression profile, we hypothesized that PPARα deficiency would alter the food entrainable response of adipose, cardiac, and liver tissues. Wild type and PPARα null mice were compared under ad libitum or restricted food access for the expression of circadian transcription factor-encoding mRNAs. Temporally restricted food access caused between a mean 5.8 to 11.5 hour phase shift in the expression profiles of the circadian genes Bmal1, Per3, and Rev-erbα in all tissues of control mice. In contrast, these same conditions phase shifted the circadian genes in tissues of PPARα null mice between a mean of 10.8 to 14.2 hr with amplitude attenuation. The food entrained phase shifts in the brown adipose and cardiac tissue circadian transcription factors of the PPARα null mice were prolonged significantly relative to wild type controls. Likewise, PPARα responsive genes in the livers of PPARα null mice exhibited a significantly prolonged phase shift relative to control mice. These findings confirm and extend recent observations in the literature.. PMID:17624301

  2. Prolonged daily light exposure increases body fat mass through attenuation of brown adipose tissue activity

    PubMed Central

    Kooijman, Sander; van den Berg, Rosa; Ramkisoensing, Ashna; Boon, Mariëtte R.; Kuipers, Eline N.; Loef, Marieke; Zonneveld, Tom C. M.; Lucassen, Eliane A.; Sips, Hetty C. M.; Chatzispyrou, Iliana A.; Houtkooper, Riekelt H.; Meijer, Johanna H.; Coomans, Claudia P.; Biermasz, Nienke R.; Rensen, Patrick C. N.

    2015-01-01

    Disruption of circadian rhythmicity is associated with obesity and related disorders, including type 2 diabetes and cardiovascular disease. Specifically, prolonged artificial light exposure associates with obesity in humans, although the underlying mechanism is unclear. Here, we report that increasing the daily hours of light exposure increases body adiposity through attenuation of brown adipose tissue (BAT) activity, a major contributor of energy expenditure. Mice exposed to a prolonged day length of 16- and 24-h light, compared with regular 12-h light, showed increased adiposity without affecting food intake or locomotor activity. Mechanistically, we demonstrated that prolonged day length decreases sympathetic input into BAT and reduces β3-adrenergic intracellular signaling. Concomitantly, prolonging day length decreased the uptake of fatty acids from triglyceride-rich lipoproteins, as well as of glucose from plasma selectively by BAT. We conclude that impaired BAT activity is an important mediator in the association between disturbed circadian rhythm and adiposity, and anticipate that activation of BAT may overcome the adverse metabolic consequences of disturbed circadian rhythmicity. PMID:25964318

  3. Effects of thyroxine on rat brown fat and muscle thermogenesis in the cold.

    PubMed

    Zaninovich, A A; Rebagliati, I; Raíces, M; Ricci, C; Hagmüller, K

    2000-05-01

    We studied whether the activation of rat brown adipose tissue (BAT) by cold exposure or by the administration of beta-3-noradrenergic agonist CGP-12177 could be prevented by the inhibition of thyroxine (T4) to triiodothyronine (T3) conversion. Hypothyroid rats were treated with replacement doses of T4, T4 plus iopanoic acid (IA) or T3. Groups of rats were placed at 4 degrees C for 24 h or kept at room temperature. Cold exposure induced a significant increase in guanosine diphosphate (GDP) binding to BAT mitochondrial proteins in T4-treated rats, an effect not abolished by IA. No significant changes were seen in T3-treated rats. In rats maintained at room temperature and injected with CGP-12177, T4 induced a significant rise in GDP binding which was not blocked by IA. T3 also induced a significant increase in binding. The study of mitochondrial oxygen consumption in muscle from cold-exposed rats showed a marked decrease in consumption in T3-treated rats as compared to values in the warm. Normal oxygen consumption was restored with 2-fold doses of T3 replacement, whereas 5-fold doses increased consumption above normal. The data suggest that in states with low or absent T3, T4 can stimulate heat production and preserve normothermia.

  4. Effect of high-fructose and high-fat diets on pulmonary sensitivity, motor activity, and body composition of brown Norway rats exposed to ozone

    EPA Pesticide Factsheets

    pulmonary parameters, BALF biomarkers, body composition, motor activity data collected from rats exposed to ozone after high fructose or high fat diets.This dataset is associated with the following publication:Gordon , C., P. Phillips , A. Johnstone , T. Beasley , A. Ledbetter , M. Schladweiler , S. Snow, and U. Kodavanti. Effect of High Fructose and High Fat Diets on Pulmonary Sensitivity, Motor Activity, and Body Composition of Brown Norway Rats Exposed to Ozone. INHALATION TOXICOLOGY. Taylor & Francis, Inc., Philadelphia, PA, USA, 28(5): 203-15, (2016).

  5. Cold-increase in brown fat thyroxine 5'-monodeiodinase is attenuated in Zucker obese rat

    SciTech Connect

    Wu, S.Y.; Stern, J.S.; Fisher, D.A.; Glick, Z.

    1987-01-01

    In this study the authors examined the possibility that the reduced brown adipose tissue (BAT) thermogenesis in the Zucker obese rat may result from a limited capacity for enzymic conversion of thyroxine (T/sub 4/) to triiodothyronine (T/sub 3/) in BAT. A total of 34 lean and obese rats, approx.4 mo old were divided into three treatment groups: group 1 (5 lean and 6 obese) was fed Purina rat chow for 21 days, and group two (5 lean and 6 obese) was fed a cafeteria diet for 21 days, and groups 3 (6 lean and 6 obese) was fed Purina rat chow and maintained in the cold (8 +/- 1/sup 0/C) for 7 days. Activity of T/sub 4/ 5'-deiodinase was determined as the rate of T/sub 3/ production from added T/sub 4/ under controlled in vitro conditions. Serum T/sub 4/ and T/sub 3/ were determined by radioimmunoassay. The rate of T/sub 4/-to-T/sub 3/ conversion in BAT was similar in the lean and obese rats maintained at room temperature, whether fed rat chow or a cafeteria diet. However, expressed per scapular BAT depot, lean rats exposed to cold displayed about a fivefold increase in BAT T/sub 3/ production whereas only a small increase was observed in the cold-exposed obese rats. Serum T/sub 3/ levels tended to be reduced in the Zucker obese rats. The data indicate a reduced capacity for T/sub 3/ production of Zucker rat BAT exposed to cold. This defect may account for the reduced tolerance of the obese animals to cold, but it does not account for their reduced diet-induced BAT thermogenesis.

  6. Oleuropein aglycone enhances UCP1 expression in brown adipose tissue in high-fat-diet-induced obese rats by activating β-adrenergic signaling.

    PubMed

    Oi-Kano, Yuriko; Iwasaki, Yusaku; Nakamura, Toshiyuki; Watanabe, Tatsuo; Goto, Tsuyoshi; Kawada, Teruo; Watanabe, Kenichi; Iwai, Kazuo

    2017-02-01

    Oleuropein is the pungent principle of raw olives. Oleuropein aglycone (OA) is a major phenolic compound in extra virgin olive oil and the absorbed form of oleuropein. We aimed to determine the mechanism underlying the nutritional effects of oleuropein and OA on interscapular brown adipose tissue (IBAT) in rats with high-fat (HF) diet-induced obesity by examining the agonistic activity of oleuropein and OA toward the transient receptor potential ankyrin 1 (TRPA1) and vanilloid 1 (TRPV1). Four-week-old male Sprague-Dawley rats were fed an HF (palm oil 30% wt:wt) diet alone or with oleuropein (HF-O, 1 g/kg diet) for 28 days. In rats fed HF-O compared to HF, urinary noradrenaline, adrenaline and UCP1 levels in IBAT were significantly higher, whereas plasma leptin levels and the total weight of the abdominal cavity adipose tissue were significantly lower. In anaesthetized 7-week-old male Sprague-Dawley rats, the OA (3.8 mg of intravenous injection)-induced increase in plasma noradrenaline secretion was suppressed by TRPA1 or TRPV1 antagonist and by a β2- or β3-adrenoceptor antagonist. Furthermore, OA-activated rat and human TRPV1s expressed on HEK293 cells at the same level as zingerone (pungent component in ginger). OA also activated humanTRPA1, and its potency was approximately 10-fold stronger than that for TRPV1. These findings suggest that OA is the agonist of both TRPA1 and TRPV1 and that OA enhances UCP1 expression in IBAT with a concomitant decrease in the visceral fat mass of HF-diet-induced obese rats through enhanced noradrenaline secretion via β-adrenergic action following TRPA1 and TRPV1 activation.

  7. Dedifferentiated fat cells: A cell source for regenerative medicine.

    PubMed

    Jumabay, Medet; Boström, Kristina I

    2015-11-26

    The identification of an ideal cell source for tissue regeneration remains a challenge in the stem cell field. The ability of progeny cells to differentiate into other cell types is important for the processes of tissue reconstruction and tissue engineering and has clinical, biochemical or molecular implications. The adaptation of stem cells from adipose tissue for use in regenerative medicine has created a new role for adipocytes. Mature adipocytes can easily be isolated from adipose cell suspensions and allowed to dedifferentiate into lipid-free multipotent cells, referred to as dedifferentiated fat (DFAT) cells. Compared to other adult stem cells, the DFAT cells have unique advantages in their abundance, ease of isolation and homogeneity. Under proper condition in vitro and in vivo, the DFAT cells have exhibited adipogenic, osteogenic, chondrogenic, cardiomyogenc, angiogenic, myogenic, and neurogenic potentials. In this review, we first discuss the phenomena of dedifferentiation and transdifferentiation of cells, and then dedifferentiation of adipocytes in particular. Understanding the dedifferentiation process itself may contribute to our knowledge of normal growth processes, as well as mechanisms of disease. Second, we highlight new developments in DFAT cell culture and summarize the current understanding of DFAT cell properties. The unique features of DFAT cells are promising for clinical applications such as tissue regeneration.

  8. Dedifferentiated fat cells: A cell source for regenerative medicine

    PubMed Central

    Jumabay, Medet; Boström, Kristina I

    2015-01-01

    The identification of an ideal cell source for tissue regeneration remains a challenge in the stem cell field. The ability of progeny cells to differentiate into other cell types is important for the processes of tissue reconstruction and tissue engineering and has clinical, biochemical or molecular implications. The adaptation of stem cells from adipose tissue for use in regenerative medicine has created a new role for adipocytes. Mature adipocytes can easily be isolated from adipose cell suspensions and allowed to dedifferentiate into lipid-free multipotent cells, referred to as dedifferentiated fat (DFAT) cells. Compared to other adult stem cells, the DFAT cells have unique advantages in their abundance, ease of isolation and homogeneity. Under proper condition in vitro and in vivo, the DFAT cells have exhibited adipogenic, osteogenic, chondrogenic, cardiomyogenc, angiogenic, myogenic, and neurogenic potentials. In this review, we first discuss the phenomena of dedifferentiation and transdifferentiation of cells, and then dedifferentiation of adipocytes in particular. Understanding the dedifferentiation process itself may contribute to our knowledge of normal growth processes, as well as mechanisms of disease. Second, we highlight new developments in DFAT cell culture and summarize the current understanding of DFAT cell properties. The unique features of DFAT cells are promising for clinical applications such as tissue regeneration. PMID:26640620

  9. Stimulation of S14 mRNA and lipogenesis in brown fat by hypothyroidism, cold exposure, and cafeteria feeding: evidence supporting a general role for S14 in lipogenesis and lipogenesis in the maintenance of thermogenesis

    SciTech Connect

    Freake, H.C.; Oppenheimer, J.H.

    1987-05-01

    In liver, thyroid hormone rapidly induces S14 mRNA, which encodes a small acidic protein. This sequence is abundantly expressed only in lipogenic tissues and is thought to have some function in fat metabolism. In the euthyroid rat, we measured 20-fold higher levels of S14 mRNA in interscapular brown adipose tissue than liver. Furthermore, whereas in liver or epididymal fat, hypothyroidism resulted in an 80% fall in S14 mRNA, in brown fat the level of this sequence increased a further 3-fold. In all three tissues, the expression of S14 mRNA correlated well with lipogenesis, as assessed by /sup 3/H/sub 2/O incorporation. Physiological activation of brown fat by chronic cold exposure or cafeteria feeding increased the concentration of S14 mRNA in this tissue and again this was accompanied by a greater rate of fatty acid synthesis. Overall, in liver and white and brown adipose tissue, S14 mRNA and lipogenesis were well correlated and strongly suggest a function of the S14 protein related to fat synthesis. These studies suggest that the S14 protein and lipogenesis may be important for thyroid hormone-induced and brown adipose tissue thermogenesis and that stimulation of these functions in hypothyroid brown fat is a consequence of decreased thyroid hormone-induced thermogenesis elsewhere.

  10. Fat, Stem Cells, and Platelet-Rich Plasma.

    PubMed

    James, Isaac B; Coleman, Sydney R; Rubin, J Peter

    2016-07-01

    The ideal filler for aesthetic surgery is inexpensive and easy to obtain, natural in appearance and texture, immunologically compatible, and long lasting without risk of infection. By most metrics, autologous fat grafts meet these criteria perfectly. Although facial fat grafting is now a commonly accepted surgical procedure, there has been a wave of activity applying stem cells and platelet-rich plasma (PRP) therapies to aesthetic practice. This article addresses technical considerations in the use of autologous fat transfer for facial rejuvenation, and also explores the current evidence for these stem cell and PRP therapies in aesthetic practice.

  11. New Physiological Aspects of Brown Adipose Tissue.

    PubMed

    Trayhurn, Paul; Arch, Jonathan R S

    2014-12-01

    Brown adipose tissue is specialised for the generation of heat by non-shivering mechanisms. In rodents, the tissue plays a role in energy balance and the development of obesity, as well as in thermoregulation. Studies using fluorodeoxyglucose positron emission tomography (FDG-PET), together with the identification of uncoupling protein-1, have provided definitive evidence that brown adipose tissue is present in adult humans. Brown fat activity is stimulated by cold exposure, declines with age and is inversely proportional to BMI. This has led to renewed interest in the tissue as a therapeutic target for the treatment of obesity. Brown adipose tissue also plays a role in glucose disposal and triglyceride clearance, implicating it in the metabolic syndrome. A potential mechanism for increasing thermogenesis is by the 'browning' of white adipose depots through the recruitment of the recently identified third type of adipocyte - the brite (or beige) fat cell.

  12. Protection against fat cell hyperplasia in a hibernator, Glis glis.

    PubMed

    Mrosovsky, N; Nash, P; Faust, I M

    1987-10-01

    Dormice, Glis glis, were fed a high-fat diet for 11 mo in one experiment: in another experiment they were fed a high-fat diet for 5 mo, either at room temperature (21.5 degrees C) or in a warm room (27 degrees C). Only in the latter group did adipocyte hyperplasia occur; this was significant in all the fat depots studied (inguinal, retroperitoneal, and gonadal). In the other groups there was no evidence of fat cell hyperplasia, despite weight gains from approximately 160 g (peaks on chow diet) to approximately 250 g (maximums on high-fat diet). Instead, fat cell size, assessed from biopsies of the inguinal area, became considerably enlarged. Taken together with earlier data from other species, the results suggest that hibernators are protected against fat cell hyperplasia. In dormice this protection appears to be present at all phases of their seasonal weight cycles. For species that experience several cycles of weight gain and loss in their lives, it may be adaptive to avoid increases in adipocyte number.

  13. Brown adipose tissue is involved in diet-induced thermogenesis and whole-body fat utilization in healthy humans

    PubMed Central

    Hibi, M; Oishi, S; Matsushita, M; Yoneshiro, T; Yamaguchi, T; Usui, C; Yasunaga, K; Katsuragi, Y; Kubota, K; Tanaka, S; Saito, M

    2016-01-01

    Background/Objectives: Brown adipose tissue (BAT) is a potential therapeutic target against obesity and diabetes through thermogenesis and substrate disposal with cold exposure. The role of BAT in energy metabolism under thermoneutral conditions, however, remains controversial. We assessed the contribution of BAT to energy expenditure (EE), particularly diet-induced thermogenesis (DIT), and substrate utilization in human adults. Methods: In this cross-sectional study, BAT activity was evaluated in 21 men using 18F-fluoro-2-deoxy-D-glucose positron emission tomography combined with computed tomography (18F-FDG-PET/CT) after cold exposure (19 °C). The subjects were divided into BAT-positive (n=13) and BAT-negative (n=8) groups according to the 18F-FDG-PET/CT findings. Twenty-four hour EE, DIT and respiratory quotient were measured using a whole-room indirect calorimeter at 27 °C. Results: Body composition, blood metabolites and 24-h EE did not differ between groups. DIT (%), calculated as DIT divided by total energy intake, however, was significantly higher in the BAT-positive group (BAT-positive: 9.7±2.5%, BAT-negative: 6.5±4.0%, P=0.03). The 24-h respiratory quotient was significantly lower (P=0.03) in the BAT-positive group (0.861±0.027) than in the BAT-negative group (0.889±0.024). Conclusion: DIT and fat utilization were higher in BAT-positive subjects compared to BAT-negative subjects, suggesting that BAT has a physiologic role in energy metabolism. PMID:27430878

  14. Historical perspectives in fat cell biology: the fat cell as a model for the investigation of hormonal and metabolic pathways.

    PubMed

    Lafontan, Max

    2012-01-15

    For many years, there was little interest in the biochemistry or physiology of adipose tissue. It is now well recognized that adipocytes play an important dynamic role in metabolic regulation. They are able to sense metabolic states via their ability to perceive a large number of nervous and hormonal signals. They are also able to produce hormones, called adipokines, that affect nutrient intake, metabolism and energy expenditure. The report by Rodbell in 1964 that intact fat cells can be obtained by collagenase digestion of adipose tissue revolutionized studies on the hormonal regulation and metabolism of the fat cell. In the context of the advent of systems biology in the field of cell biology, the present seems an appropriate time to look back at the global contribution of the fat cell to cell biology knowledge. This review focuses on the very early approaches that used the fat cell as a tool to discover and understand various cellular mechanisms. Attention essentially focuses on the early investigations revealing the major contribution of mature fat cells and also fat cells originating from adipose cell lines to the discovery of major events related to hormone action (hormone receptors and transduction pathways involved in hormonal signaling) and mechanisms involved in metabolite processing (hexose uptake and uptake, storage, and efflux of fatty acids). Dormant preadipocytes exist in the stroma-vascular fraction of the adipose tissue of rodents and humans; cell culture systems have proven to be valuable models for the study of the processes involved in the formation of new fat cells. Finally, more recent insights into adipocyte secretion, a completely new role with major metabolic impact, are also briefly summarized.

  15. The Molecular Signature of HIV-1-Associated Lipomatosis Reveals Differential Involvement of Brown and Beige/Brite Adipocyte Cell Lineages

    PubMed Central

    Cereijo, Rubén; Gallego-Escuredo, José Miguel; Moure, Ricardo; Villarroya, Joan; Domingo, Joan Carles; Fontdevila, Joan; Martínez, Esteban; Gutiérrez, Maria del Mar; Mateo, María Gracia; Giralt, Marta; Domingo, Pere; Villarroya, Francesc

    2015-01-01

    Highly active antiretroviral therapy has remarkably improved quality of life of HIV-1-infected patients. However, this treatment has been associated with the so-called lipodystrophic syndrome, which conveys a number of adverse metabolic effects and morphological alterations. Among them, lipoatrophy of subcutaneous fat in certain anatomical areas and hypertrophy of visceral depots are the most common. Less frequently, lipomatous enlargements of subcutaneous fat at distinct anatomic areas occur. Lipomatous adipose tissue in the dorso-cervical area (“buffalo hump”) has been associated with a partial white-to-brown phenotype transition and with increased cell proliferation, but, to date, lipomatous enlargements arising in other parts of the body have not been characterized. In order to establish the main molecular events associated with the appearance of lipomatosis in HIV-1 patients, we analyzed biopsies of lipomatous tissue from “buffalo hump” and from other anatomical areas in patients, in comparison with healthy subcutaneous adipose tissue, using a marker gene expression approach. Both buffalo-hump and non-buffalo-hump lipomatous adipose tissues exhibited similar patterns of non-compromised adipogenesis, unaltered inflammation, non-fibrotic phenotype and proliferative activity. Shorter telomere length, prelamin A accumulation and SA-β-Gal induction, reminiscent of adipocyte senescence, were also common to both types of lipomatous tissues. Buffalo hump biopsies showed expression of marker genes of brown adipose tissue (e.g. UCP1) and, specifically, of “classical” brown adipocytes (e.g. ZIC1) but not of beige/brite adipocytes. No such brown fat-related gene expression occurred in lipomatous tissues at other anatomical sites. In conclusion, buffalo hump and other subcutaneous adipose tissue enlargements from HIV-1-infected patients share a similar lipomatous character. However, a distorted induction of white-to-“classical brown adipocyte” phenotype

  16. Cell-autonomous activation of Hedgehog signaling inhibits brown adipose tissue development

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Although recent studies have shown that brown adipose tissue (BAT) arises from progenitor cells that also give rise to skeletal muscle, the developmental signals that control the formation of BAT remain largely unknown. Here, we show that brown preadipocytes possess primary cilia and can respond to ...

  17. Isolation of Precursor Cells from Waste Solid Fat Tissue

    NASA Technical Reports Server (NTRS)

    Byerly, Diane; Sognier, Marguerite A.

    2009-01-01

    A process for isolating tissue-specific progenitor cells exploits solid fat tissue obtained as waste from such elective surgical procedures as abdominoplasties (tummy tucks) and breast reductions. Until now, a painful and risky process of aspiration of bone marrow has been used to obtain a limited number of tissue- specific progenitor cells. The present process yields more tissue-specific progenitor cells and involves much less pain and risk for the patient. This process includes separation of fat from skin, mincing of the fat into small pieces, and forcing a fat saline mixture through a sieve. The mixture is then digested with collagenase type I in an incubator. After centrifugation tissue-specific progenitor cells are recovered and placed in a tissue-culture medium in flasks or Petri dishes. The tissue-specific progenitor cells can be used for such purposes as (1) generating three-dimensional tissue equivalent models for studying bone loss and muscle atrophy (among other deficiencies) and, ultimately, (2) generating replacements for tissues lost by the fat donor because of injury or disease.

  18. Effect of high-fructose and high-fat diets on pulmonary sensitivity, motor activity, and body composition of brown Norway rats exposed to ozone.

    PubMed

    Gordon, C J; Phillips, P M; Johnstone, A F M; Beasley, T E; Ledbetter, A D; Schladweiler, M C; Snow, S J; Kodavanti, U P

    2016-04-01

    Diet-induced obesity has been suggested to lead to increased susceptibility to air pollutants such as ozone (O3); however, there is little experimental evidence. Thirty day old male and female Brown Norway rats were fed a normal, high-fructose or high-fat diet for 12 weeks and then exposed to O3 (acute - air or 0.8 ppm O3 for 5 h, or subacute - air or 0.8 ppm O3 for 5 h/d 1 d/week for 4 weeks). Body composition was measured non-invasively using NMR. Ventilatory parameters and exploratory behavior were measured after the third week of subacute exposure. Bronchoalveolar lavage fluid (BALF) and blood chemistry data were collected 18 h after acute O3 and 18 h after the fourth week of subacute O3. The diets led to increased body fat in male but not female rats. O3-induced changes in ventilatory function were either unaffected or improved with the fructose and fat diets. O3-induced reduction in exploratory behavior was attenuated with fructose and fat diets in males and partially in females. O3 led to a significant decrease in body fat of males fed control diet but not the fructose or fat diet. O3 led to significant increases in BALF eosinophils, increase in albumin, and reductions in macrophages. Female rats appeared to be more affected than males to O3 regardless of diet. Overall, treatment with high-fructose and high-fat diets attenuated some O3 induced effects on pulmonary function, behavior, and metabolism. Exacerbation of toxicity was observed less frequently.

  19. Opportunities and Challenges in Three-dimensional Brown Adipogenesis of Stem Cells

    PubMed Central

    Unser, Andrea M.; Tian, Yangzi; Xie, Yubing

    2015-01-01

    The formation of brown adipose tissue (BAT) via brown adipogenesis has become a notable process due to its ability to expend energy as heat with implications in the treatment of metabolic disorders and obesity. With the advent of complexity within white adipose tissue (WAT) along with inducible brown adipocytes (also known as brite and beige), there has been a surge in deciphering adipocyte biology as well as in vivo adipogenic microenvironments. A therapeutic outcome would benefit from understanding early events in brown adipogenesis, which can be accomplished by studying cellular differentiation. Pluripotent stem cells are an efficient model for differentiation and have been directed towards both white adipogenic and brown adipogenic lineages. The stem cell microenvironment greatly contributes to terminal cell fate and as such, has been mimicked extensively by various polymers including those that can form 3D hydrogel constructs capable of biochemical and/or mechanical modifications and modulations. Using bioengineering approaches towards the creation of 3D cell culture arrangements is more beneficial than traditional 2D culture in that it better recapitulates the native tissue biochemically and biomechanically. In addition, such an approach could potentially protect the tissue formed from necrosis and allow for more efficient implantation. In this review, we highlight the promise of brown adipocytes with a focus on brown adipogenic differentiation of stem cells using bioengineering approaches, along with potential challenges and opportunities that arise when considering the energy expenditure of BAT for prospective therapeutics. PMID:26231586

  20. Small Buccal Fat Pad Cells Have High Osteogenic Differentiation Potential.

    PubMed

    Tsurumachi, Niina; Akita, Daisuke; Kano, Koichiro; Matsumoto, Taro; Toriumi, Taku; Kazama, Tomohiko; Oki, Yoshinao; Tamura, Yoko; Tonogi, Morio; Isokawa, Keitaro; Shimizu, Noriyoshi; Honda, Masaki

    2016-03-01

    Dedifferentiated fat (DFAT) cells derived from mature adipocytes have mesenchymal stem cells' (MSCs) characteristics. Generally, mature adipocytes are 60-110 μm in diameter; however, association between adipocyte size and dedifferentiation efficiency is still unknown. This study, therefore, investigated the dedifferentiation efficiency of adipocytes based on cell diameter. Buccal fat pad was harvested from five human donors and dissociated by collagenase digestion. After exclusion of unwanted stromal cells by centrifugation, floating adipocytes were collected and their size distribution was analyzed. The floating adipocytes were then separated into two groups depending on cell size using 40- and 100-μm nylon mesh filters: cell diameters less than 40 μm (small adipocytes: S-adipocytes) and cell diameters of 40-100 μm (large adipocytes: L-adipocytes). Finally, we evaluated the efficiency of adipocyte dedifferentiation and then characterized the resultant DFAT cells. The S-adipocytes showed a higher capacity to dedifferentiate into DFAT cells (S-DFAT cells) compared to the L-adipocytes (L-DFAT cells). The S-DFAT cells also showed a relatively higher proportion of CD146-positive cells than L-DFAT cells, and exhibited more osteogenic differentiation ability based on the alkaline phosphatase activity and amount of calcium deposition. These results suggested that the S- and L-DFAT cells had distinct characteristics, and that the higher dedifferentiation potential of S-adipocytes compared to L-adipocytes gives the former group an advantage in yielding DFAT cells.

  1. TRPV1 agonist monoacylglycerol increases UCP1 content in brown adipose tissue and suppresses accumulation of visceral fat in mice fed a high-fat and high-sucrose diet.

    PubMed

    Iwasaki, Yusaku; Tamura, Yasuko; Inayoshi, Kimiko; Narukawa, Masataka; Kobata, Kenji; Chiba, Hiroshige; Muraki, Etsuko; Tsunoda, Nobuyo; Watanabe, Tatsuo

    2011-01-01

    The administration of such a transient receptor potential vanilloid 1 (TRPV1) agonist as capsaicin, which is a pungent ingredient of red pepper, promotes energy metabolism and suppresses visceral fat accumulation. We have recently identified monoacylglycerols (MGs) having an unsaturated long-chain fatty acid as the novel TRPV1 agonist in foods. We investigated in this present study the effects of dietary MGs on uncoupling protein 1 (UCP1) expression in interscapular brown adipose tissue (IBAT) and on fat accumulation in mice fed with a high-fat, high-sucrose diet. The MG30 diet that substituted 30% of all lipids for MGs (a mixture of 1-oleoylglycerol, 1-linoleoylglycerol and 1-linolenoylglycerol) significantly increased the UCP1 content of IBAT and decreased the weight of epididymal white adipose tissue, and the serum glucose, total cholesterol and free fatty acid levels. The diet containing only 1-oleoylglycerol as MG also increased UCP1 expression in IBAT. MGs that activated TRPV1 also therefore induced the expression of UCP 1 and prevented visceral fat accumulation as well as capsaicin.

  2. Lower weight gain and hepatic lipid content in hamsters fed high fat diets supplemented with white rice protein, brown rice protein, soy protein, and their hydrolysates.

    PubMed

    Zhang, Huijuan; Bartley, Glenn E; Mitchell, Cheryl R; Zhang, Hui; Yokoyama, Wallace

    2011-10-26

    The physiological effects of the hydrolysates of white rice protein (WRP), brown rice protein (BRP), and soy protein (SP) hydrolyzed by the food grade enzyme, alcalase2.4 L, were compared to the original protein source. Male Syrian Golden hamsters were fed high-fat diets containing either 20% casein (control) or 20% extracted proteins or their hydrolysates as the protein source for 3 weeks. The brown rice protein hydrolysate (BRPH) diet group reduced weight gain 76% compared with the control. Animals fed the BRPH supplemented diet also had lower final body weight, liver weight, very low density lipoprotein cholesterol (VLDL-C), and liver cholesterol, and higher fecal fat and bile acid excretion than the control. Expression levels of hepatic genes for lipid oxidation, PPARα, ACOX1, and CPT1, were highest for hamsters fed the BRPH supplemented diet. Expression of CYP7A1, the gene regulating bile acid synthesis, was higher in all test groups. Expression of CYP51, a gene coding for an enzyme involved in cholesterol synthesis, was highest in the BRPH diet group. The results suggest that BRPH includes unique peptides that reduce weight gain and hepatic cholesterol synthesis.

  3. Concomitant deletions of tumor suppressor genes MEN1 and AIP are essential for the pathogenesis of the brown fat tumor hibernoma.

    PubMed

    Nord, Karolin H; Magnusson, Linda; Isaksson, Margareth; Nilsson, Jenny; Lilljebjörn, Henrik; Domanski, Henryk A; Kindblom, Lars-Gunnar; Mandahl, Nils; Mertens, Fredrik

    2010-12-07

    Hibernomas are benign tumors with morphological features resembling brown fat. They consistently display cytogenetic rearrangements, typically translocations, involving chromosome band 11q13. Here we demonstrate that these aberrations are associated with concomitant deletions of AIP and MEN1, tumor suppressor genes that are located 3 Mb apart and that underlie the hereditary syndromes pituitary adenoma predisposition and multiple endocrine neoplasia type I. MEN1 and AIP displayed a low expression in hibernomas whereas the expression of genes up-regulated in brown fat--PPARA, PPARG, PPARGC1A, and UCP1--was high. Thus, loss of MEN1 and AIP is likely to be pathogenetically essential for hibernoma development. Simultaneous loss of two tumor suppressor genes has not previously been shown to result from a neoplasia-associated translocation. Furthermore, in contrast to the prevailing assumption that benign tumors harbor relatively few genetic aberrations, the present analyses demonstrate that a considerable number of chromosome breaks are involved in the pathogenesis of hibernoma.

  4. Dietary gamma-linolenic acid in the form of borage oil causes less body fat accumulation accompanying an increase in uncoupling protein 1 mRNA level in brown adipose tissue.

    PubMed

    Takahashi, Y; Ide, T; Fujita, H

    2000-10-01

    Rats were fed a low-fat diet containing 2% safflower oil or 20% fat diets containing either safflower oil rich in linoleic acid, borage oil containing 25% gamma (gamma)-linolenic acid or enzymatically prepared gamma-linolenic acid enriched borage oil containing 47% gamma-linolenic acid for 14 days. Energy intake and growth of animals were the same among groups. A high safflower oil diet compared with a low-fat diet caused significant increases in both epididymal and perirenal white adipose tissue weights. However, high-fat diets rich in gamma-linolenic acid failed to do so. Compared with a low-fat diet, all the high-fat diets increased mRNA levels of uncoupling protein 1 and lipoprotein lipase in brown adipose tissue. The extents of the increase were greater with high-fat diets rich in gamma-linolenic acid. Various high-fat diets, compared with a low-fat diet, decreased glucose transporter 4 mRNA in white adipose tissue to the same levels. The amount and types of dietary fat did not affect the leptin mRNA level in epididymal white adipose tissue. However, a high safflower oil diet, but not high-fat diets rich in gamma-linolenic acid relative to a low-fat diet, increased perirenal white adipose tissue leptin mRNA levels. All high-fat diets, relative to a low-fat diet, increased the hepatic mitochondrial fatty acid oxidation rate and fatty acid oxidation enzyme mRNA abundances to the same levels. High-fat diets also increased these parameters in the peroxisomal pathway, and the increases were greater with high-fat diets rich in gamma-linolenic acid. The physiological activity in increasing brown adipose tissue gene expression and peroxisomal fatty acid oxidation was similar between the two types of borage oil differing in gamma-linolenic acid content. It was suggested that dietary gamma-linolenic acid attenuates body fat accumulation through the increase in gene expressions of uncoupling protein 1 in brown adipose tissue. An increase in hepatic peroxisomal fatty acid

  5. Characteristics and multipotency of equine dedifferentiated fat cells.

    PubMed

    Murata, Daiki; Yamasaki, Atsushi; Matsuzaki, Shouta; Sunaga, Takafumi; Fujiki, Makoto; Tokunaga, Satoshi; Misumi, Kazuhiro

    2016-01-01

    Dedifferentiated fat (DFAT) cells have been shown to be multipotent, similar to mesenchymal stem cells (MSCs). In this study, we aimed to establish and characterize equine DFAT cells. Equine adipocytes were ceiling cultured, and then dedifferentiated into DFAT cells by the seventh day of culture. The number of DFAT cells was increased to over 10 million by the fourth passage. Flow cytometry of DFAT cells showed that the cells were strongly positive for CD44, CD90, and major histocompatibility complex (MHC) class I; moderately positive for CD11a/18, CD105, and MHC class II; and negative for CD34 and CD45. Moreover, DFAT cells were positive for the expression of sex determining region Y-box 2 as a marker of multipotency. Finally, we found that DFAT cells could differentiate into osteogenic, chondrogenic, and adipogenic lineages under specific nutrient conditions. Thus, DFAT cells could have clinical applications in tissue regeneration, similar to MSCs derived from adipose tissue.

  6. The cell biology of fat expansion

    PubMed Central

    Rutkowski, Joseph M.; Stern, Jennifer H.

    2015-01-01

    Adipose tissue is a complex, multicellular organ that profoundly influences the function of nearly all other organ systems through its diverse metabolite and adipokine secretome. Adipocytes are the primary cell type of adipose tissue and play a key role in maintaining energy homeostasis. The efficiency with which adipose tissue responds to whole-body energetic demands reflects the ability of adipocytes to adapt to an altered nutrient environment, and has profound systemic implications. Deciphering adipocyte cell biology is an important component of understanding how the aberrant physiology of expanding adipose tissue contributes to the metabolic dysregulation associated with obesity. PMID:25733711

  7. Dual Processing of FAT1 Cadherin Protein by Human Melanoma Cells Generates Distinct Protein Products*

    PubMed Central

    Sadeqzadeh, Elham; de Bock, Charles E.; Zhang, Xu Dong; Shipman, Kristy L.; Scott, Naomi M.; Song, Chaojun; Yeadon, Trina; Oliveira, Camila S.; Jin, Boquan; Hersey, Peter; Boyd, Andrew W.; Burns, Gordon F.; Thorne, Rick F.

    2011-01-01

    The giant cadherin FAT1 is one of four vertebrate orthologues of the Drosophila tumor suppressor fat. It engages in several functions, including cell polarity and migration, and in Hippo signaling during development. Homozygous deletions in oral cancer suggest that FAT1 may play a tumor suppressor role, although overexpression of FAT1 has been reported in some other cancers. Here we show using Northern blotting that human melanoma cell lines variably but universally express FAT1 and less commonly FAT2, FAT3, and FAT4. Both normal melanocytes and keratinocytes also express comparable FAT1 mRNA relative to melanoma cells. Analysis of the protein processing of FAT1 in keratinocytes revealed that, like Drosophila FAT, human FAT1 is cleaved into a non-covalent heterodimer before achieving cell surface expression. The use of inhibitors also established that such cleavage requires the proprotein convertase furin. However, in melanoma cells, the non-cleaved proform of FAT1 is also expressed at the cell surface together with the furin-cleaved heterodimer. Moreover, furin-independent processing generates a potentially functional proteolytic product in melanoma cells, a persistent 65-kDa membrane-bound cytoplasmic fragment no longer in association with the extracellular fragment. In vitro localization studies of FAT1 showed that melanoma cells display high levels of cytosolic FAT1 protein, whereas keratinocytes, despite comparable FAT1 expression levels, exhibited mainly cell-cell junctional staining. Such differences in protein distribution appear to reconcile with the different protein products generated by dual FAT1 processing. We suggest that the uncleaved FAT1 could promote altered signaling, and the novel products of alternate processing provide a dominant negative function in melanoma. PMID:21680732

  8. Liver X receptor β: new player in the regulatory network of thyroid hormone and 'browning' of white fat.

    PubMed

    Miao, Yifei; Warner, Margaret; Gustafsson, Jan-Ke

    2016-01-01

    The recent discovery of browning of white adipose tissue (WAT) has raised great research interest because of its significant potential in counteracting obesity and type II diabetes. However, the mechanisms underlying browning are still poorly understood. Liver X receptors (LXRs) are one class of nuclear receptors, which play a vital role in regulating cholesterol, triglyceride and glucose metabolism. Following our previous finding that LXRs serve as repressors of UCP1 in classic brown adipose tissue in female mice, we found that LXRs, especially LXRβ, also repress the browning process of subcutaneous adipose tissue (SAT) in male rodents fed a normal diet. Depletion of LXRs activated thyrotropin releasing hormone positive neurons in the paraventricular area of the hypothalamus, and thus stimulated secretion of thyroid-stimulating hormone from the pituitary. Consequently production of thyroid hormones in the thyroid gland and circulating thyroid hormone level were increased. Moreover, the activity of thyroid signaling in SAT was markedly increased. One unexpected finding of our study is that LXRs are indispensable in the thyroid hormone negative feedback loop at the level of the hypothalamus. LXRs maintain expression of thyroid receptors in the brain and when they are inactivated there is no negative feedback of thyroid hormone in the hypothalamus. Together, our findings have uncovered the basis of increased energy expenditure in male LXR knock-out mice and provided support for targeting LXRs in treatment of obesity.

  9. Notch Signaling Rescues Loss of Satellite Cells Lacking Pax7 and Promotes Brown Adipogenic Differentiation

    PubMed Central

    Pasut, Alessandra; Chang, Natasha C.; Rodriguez, Uxia Gurriaran; Faulkes, Sharlene; Yin, Hang; Lacaria, Melanie; Ming, Hong; Rudnicki, Michael A.

    2016-01-01

    Summary Pax7 is a nodal transcription factor that is essential for regulating the maintenance, expansion, and myogenic identity of satellite cells during both neonatal and adult myogenesis. Deletion of Pax7 results in loss of satellite cells and impaired muscle regeneration. Here we show that ectopic expression of the constitutively active intracellular domain of Notch1 (NICD1) rescues the loss of Pax7-deficient satellite cells and restores their proliferative potential. Strikingly NICD1-expressing satellite cells do not undergo myogenic differentiation and instead acquire a brown adipogenic fate both in vivo and in vitro. NICD-expressing Pax7-/- satellite cells fail to upregulate MyoD and instead express the brown adipogenic marker PRDM16. Overall these results show that Notch1 activation compensates for the loss of Pax7 in the quiescent state and acts as a molecular switch to promote brown adipogenesis in adult skeletal muscle. PMID:27346341

  10. Notch Signaling Rescues Loss of Satellite Cells Lacking Pax7 and Promotes Brown Adipogenic Differentiation.

    PubMed

    Pasut, Alessandra; Chang, Natasha C; Rodriguez, Uxia Gurriaran; Faulkes, Sharlene; Yin, Hang; Lacaria, Melanie; Ming, Hong; Rudnicki, Michael A

    2016-07-12

    Pax7 is a nodal transcription factor that is essential for regulating the maintenance, expansion, and myogenic identity of satellite cells during both neonatal and adult myogenesis. Deletion of Pax7 results in loss of satellite cells and impaired muscle regeneration. Here, we show that ectopic expression of the constitutively active intracellular domain of Notch1 (NICD1) rescues the loss of Pax7-deficient satellite cells and restores their proliferative potential. Strikingly NICD1-expressing satellite cells do not undergo myogenic differentiation and instead acquire a brown adipogenic fate both in vivo and in vitro. NICD-expressing Pax7(-/-) satellite cells fail to upregulate MyoD and instead express the brown adipogenic marker PRDM16. Overall, these results show that Notch1 activation compensates for the loss of Pax7 in the quiescent state and acts as a molecular switch to promote brown adipogenesis in adult skeletal muscle.

  11. Mature adipocyte-derived dedifferentiated fat cells exhibit multilineage potential.

    PubMed

    Matsumoto, Taro; Kano, Koichiro; Kondo, Daisuke; Fukuda, Noboru; Iribe, Yuji; Tanaka, Nobuaki; Matsubara, Yoshiyuki; Sakuma, Takahiro; Satomi, Aya; Otaki, Munenori; Ryu, Jyunnosuke; Mugishima, Hideo

    2008-04-01

    When mature adipocytes are subjected to an in vitro dedifferentiation strategy referred to as ceiling culture, these mature adipocytes can revert to a more primitive phenotype and gain cell proliferative ability. We refer to these cells as dedifferentiated fat (DFAT) cells. In the present study, we examined the multilineage differentiation potential of DFAT cells. DFAT cells obtained from adipose tissues of 18 donors exhibited a fibroblast-like morphology and sustained high proliferative activity. Flow cytometric analysis revealed that DFAT cells comprised a highly homogeneous cell population compared with that of adipose-derived stem/stromal cells (ASCs), although the cell-surface antigen profile of DFAT cells was very similar to that of ASCs. DFAT cells lost expression of mature adipocytes marker genes but retained or gained expression of mesenchymal lineage-committed marker genes such as peroxisome proliferator-activated receptor gamma (PPARgamma), RUNX2, and SOX9. In vitro differentiation analysis revealed that DFAT cells could differentiate into adipocytes, chondrocytes, and osteoblasts under appropriate culture conditions. DFAT cells also formed osteoid matrix when implanted subcutaneously into nude mice. In addition, clonally expanded porcine DFAT cells showed the ability to differentiate into multiple mesenchymal cell lineages. These results indicate that DFAT cells represent a type of multipotent progenitor cell. The accessibility and ease of culture of DFAT cells support their potential application for cell-based therapies.

  12. Capillary Isoelectric Focusing Immunoassay for Fat Cell Differentiation Proteomics.

    PubMed

    Johlfs, Mary G; Gorjala, Priyatham; Urasaki, Yasuyo; Le, Thuc T; Fiscus, Ronald R

    2015-01-01

    Profiling cellular proteome is critical to understanding signal integration during cell fate determination. In this study, the capability of capillary isoelectric focusing (cIEF) immunoassays to detect post-translational modifications (PTM) of protein isoforms is demonstrated. cIEF immunoassays exhibit protein detection sensitivity at up to 5 orders of magnitude higher than traditional methods. This detection ultra-sensitivity permits proteomic profiling of several nanograms of tissue samples. cIEF immunoassays are employed to simultaneously profile three protein kinases during fat cell differentiation: cGMP-dependent protein kinase type I (PKG-I) of the nitric oxide (NO) signaling pathway, protein kinase B (Akt) of the insulin signaling pathway, and extracellular signal-regulated kinase (ERK) of the mitogen-activated protein kinase (MAPK) signaling pathway. Interestingly, a switch in the expression level of PKG- isoforms is observed during fat cell differentiation. While both PKG-Iα and PKG-Iβ isoforms are present in preadipocytes, only PKG-Iβ isoform is expressed in adipocytes. On the other hand, the phosphorylation level increases for Akt while decreases for ERK1 and ERK2 following the maturation of preadipocytes into adipocytes. Taken together, cIEF immunoassay provides a highly sensitive means to study fat cell differentiation proteomics. cIEF immunoassay should be a powerful proteomics tool to study complex protein signal integration in biological systems.

  13. Capillary Isoelectric Focusing Immunoassay for Fat Cell Differentiation Proteomics

    PubMed Central

    Johlfs, Mary G.; Gorjala, Priyatham; Urasaki, Yasuyo; Le, Thuc T.; Fiscus, Ronald R.

    2015-01-01

    Profiling cellular proteome is critical to understanding signal integration during cell fate determination. In this study, the capability of capillary isoelectric focusing (cIEF) immunoassays to detect post-translational modifications (PTM) of protein isoforms is demonstrated. cIEF immunoassays exhibit protein detection sensitivity at up to 5 orders of magnitude higher than traditional methods. This detection ultra-sensitivity permits proteomic profiling of several nanograms of tissue samples. cIEF immunoassays are employed to simultaneously profile three protein kinases during fat cell differentiation: cGMP-dependent protein kinase type I (PKG-I) of the nitric oxide (NO) signaling pathway, protein kinase B (Akt) of the insulin signaling pathway, and extracellular signal-regulated kinase (ERK) of the mitogen-activated protein kinase (MAPK) signaling pathway. Interestingly, a switch in the expression level of PKG- isoforms is observed during fat cell differentiation. While both PKG-Iα and PKG-Iβ isoforms are present in preadipocytes, only PKG-Iβ isoform is expressed in adipocytes. On the other hand, the phosphorylation level increases for Akt while decreases for ERK1 and ERK2 following the maturation of preadipocytes into adipocytes. Taken together, cIEF immunoassay provides a highly sensitive means to study fat cell differentiation proteomics. cIEF immunoassay should be a powerful proteomics tool to study complex protein signal integration in biological systems. PMID:26132171

  14. Dedifferentiated fat cells differentiate into osteoblasts in titanium fiber mesh.

    PubMed

    Kishimoto, Naotaka; Momota, Yoshihiro; Hashimoto, Yoshiya; Ando, Kayoko; Omasa, Takeshi; Kotani, Junichiro

    2013-01-01

    Mature adipocyte-derived dedifferentiated fat (DFAT) cells rapidly differentiate into osteoblasts under three-dimensional culture conditions. However, it has not been demonstrated that DFAT cells can differentiate into osteoblasts in a rigid scaffold consisting of titanium fiber mesh (TFM). We examined the proliferation and osteogenic differentiation ability of DFAT cells using TFM as a scaffold. DFAT cells derived from rabbit subcutaneous fat were seeded into TFM and cultured in osteogenic medium containing dexamethasone, L-ascorbic acid 2-phosphate and β-glycerophosphate for 14 days. In scanning electron microscopy (SEM) analysis, well-spread cells covered the titanium fibers on day 3, and appeared to increase in number from day 3 to 7. Numerous globular accretions were found and almost completely covered the fibers on day 14. Cell proliferation, as measured by DNA content in the TFM, was significantly higher on day 7 compared with that of day 1. Osteocalcin and calcium content in the TFM were significantly higher on day 14 compared to those of days 1, 3, and 7, indicating DFAT cells differentiated into osteoblasts. We theorize that globular accretions observed in SEM analysis may be calcified matrix resulting from osteocalcin secreted by osteoblasts binding calcium contained in fetal bovine serum. In this study, we demonstrated that DFAT cells differentiate into osteoblasts and deposit mineralized matrices in TFM. Therefore, the combination of DFAT cells and TFM may be an attractive option for bone tissue engineering.

  15. Spectroscopic, scanning laser OBIC, and I-V/QE characterizations of browned EVA solar cells

    SciTech Connect

    Pern, F.J.; Eisgruber, I.L.; Micheels, R.H.

    1996-05-01

    The effects of ethylene-vinyl acetate (EVA) discoloration due to accelerated field or laboratory exposure on the encapsulated silicon (Si) solar cells or EVA/glass laminates were characterized quantitatively by using non-invasive, non-destructive ultraviolet-visible (UV-vis) spectrophotometry, spectrocolorimetry, spectrofluorometry, scanning laser OBIC (optical beam induced current) spectroscopy, and current-voltage (I-V) and quantum efficiency (QE) measurements. The results show that the yellowness index (YI) measured directly over the AR-coated solar cells under the glass superstrate increased from the range of -80 to -90 to the range of -20 to 15 as the EVA changed from clear to brown. The ratio of two fluorescence emission peak areas generally increased from 1.45 to 5.69 as browning increased, but dropped to 4.21 on a darker EVA. For a solar cell with brown EVA in the central region, small-area grating QE measurements and scanning laser OBIC analysis between the brown and clear EVA regions showed that the quantum efficiency loss at 633 nm was 42%-48% of the loss at 488 nm, due to a reduced decrease of transmittance in browned EVA at the longer wavelengths. The portion of the solar cell under the browned EVA showed a decrease of {approximately}36% in efficiency, as compared to the cell efficiency under clear EVA. Transmittance loss at 633 nm was 38% of the loss at 488 nm for a light yellow-brown EVA/glass laminate that showed a small increase of 10 in the yellowness index.

  16. Adipose tissue NAPE-PLD controls fat mass development by altering the browning process and gut microbiota

    PubMed Central

    Geurts, Lucie; Everard, Amandine; Van Hul, Matthias; Essaghir, Ahmed; Duparc, Thibaut; Matamoros, Sébastien; Plovier, Hubert; Castel, Julien; Denis, Raphael G. P.; Bergiers, Marie; Druart, Céline; Alhouayek, Mireille; Delzenne, Nathalie M.; Muccioli, Giulio G.; Demoulin, Jean-Baptiste; Luquet, Serge; Cani, Patrice D.

    2015-01-01

    Obesity is a pandemic disease associated with many metabolic alterations and involves several organs and systems. The endocannabinoid system (ECS) appears to be a key regulator of energy homeostasis and metabolism. Here we show that specific deletion of the ECS synthesizing enzyme, NAPE-PLD, in adipocytes induces obesity, glucose intolerance, adipose tissue inflammation and altered lipid metabolism. We report that Napepld-deleted mice present an altered browning programme and are less responsive to cold-induced browning, highlighting the essential role of NAPE-PLD in regulating energy homeostasis and metabolism in the physiological state. Our results indicate that these alterations are mediated by a shift in gut microbiota composition that can partially transfer the phenotype to germ-free mice. Together, our findings uncover a role of adipose tissue NAPE-PLD on whole-body metabolism and provide support for targeting NAPE-PLD-derived bioactive lipids to treat obesity and related metabolic disorders. PMID:25757720

  17. The Relationship Between Brown Adipose Tissue Content in Supraclavicular Fat Depots and Insulin Sensitivity in Patients with Type 2 Diabetes Mellitus and Prediabetes

    PubMed Central

    Ustyuzhanin, Dmitry; Philippov, Yury; Mayorov, Alexander; Shestakova, Marina; Shariya, Merab; Ternovoy, Sergey; Dedov, Ivan

    2017-01-01

    Abstract Background: The evaluation of brown adipose tissue (BAT) and its role in metabolism and obesity remains an important topic in the recent literature. This study evaluated the influence of the BAT triglyceride content measured by proton magnetic resonance (MR) spectroscopy in patients with type 2 diabetes mellitus (DM2) and prediabetes on insulin sensitivity. Methods: A total of 25 patients with DM2 and prediabetes (45.9 ± 10.1 years old, body mass index [BMI] of 31.6 ± 5.4 kg/m2) underwent anthropometric measurements (BMI), insulin sensitivity analysis (M value during euglycemic hyperinsulinemic clamp and homeostasis model assessment of insulin resistance), proton MR spectroscopy, and blood tests (total cholesterol, low-density lipoproteins, high-density lipoproteins, and triglycerides). The relationship between the triglyceride content in the supraclavicular fat depot and insulin sensitivity, anthropometric measurements, and blood test results was assessed. Results: The triglyceride content in the supraclavicular fat depot varied between 79.2% and 97.1% (mean: 92.6% ± 4.2%). The triglyceride content in the subcutaneous white adipose tissue of the neck was significantly higher (85.3%–99.3%; mean: 95.5% ± 2.9%; P = 0.0007). The triglyceride content in the supraclavicular fat depot exhibited a significantly moderate correlation with the BMI (r = 0.64; P = 0.0009). A significant weak negative correlation between the supraclavicular fat content and M value was revealed (r = −0.44; P = 0.002). Patients with high insulin resistance (IR) had a higher triglyceride content in the supraclavicular fat depot than patients with normal and lower IR (94.3% ± 2.0% vs. 90.4% ± 5.2%; P = 0.02). Conclusions: Reducing the BAT content in the supraclavicular fat depot can influence the development of IR in patients with DM2 and prediabetes. PMID:28118051

  18. Exosomal microRNA miR-92a concentration in serum reflects human brown fat activity

    PubMed Central

    Chen, Yong; Buyel, Joschka J.; Hanssen, Mark J. W.; Siegel, Franziska; Pan, Ruping; Naumann, Jennifer; Schell, Michael; van der Lans, Anouk; Schlein, Christian; Froehlich, Holger; Heeren, Joerg; Virtanen, Kirsi A.; van Marken Lichtenbelt, Wouter; Pfeifer, Alexander

    2016-01-01

    Brown adipose tissue (BAT) dissipates energy and its activity correlates with leanness in human adults. 18F-fluorodeoxyglucose (18F-FDG) positron emission tomography coupled with computer tomography (PET/CT) is still the standard for measuring BAT activity, but exposes subjects to ionizing radiation. To study BAT function in large human cohorts, novel diagnostic tools are needed. Here we show that brown adipocytes release exosomes and that BAT activation increases exosome release. Profiling miRNAs in exosomes released from brown adipocytes, and in exosomes isolated from mouse serum, we show that levels of miRNAs change after BAT activation in vitro and in vivo. One of these exosomal miRNAs, miR-92a, is also present in human serum exosomes. Importantly, serum concentrations of exosomal miR-92a inversely correlate with human BAT activity measured by 18F-FDG PET/CT in two unique and independent cohorts comprising 41 healthy individuals. Thus, exosomal miR-92a represents a potential serum biomarker for BAT activity in mice and humans. PMID:27117818

  19. MicroRNA Functions in Brite/Brown Fat — Novel Perspectives towards Anti-Obesity Strategies

    PubMed Central

    Karbiener, Michael; Scheideler, Marcel

    2014-01-01

    Current anti-obesity strategies are aiming at restricting energy uptake, but still, obesity treatment is far from being satisfactory. The discovery of active brown adipose tissue (BAT) in adult humans currently opens new avenues to combat obesity and follow-up complications as it tackles the other site of the energy balance: energy expenditure via non-shivering thermogenesis. This process of energy dissipation in the adipose tissue is tightly controlled, and the elucidation of its regulatory network is a key plank for therapeutic applications. MicroRNAs (miRNAs) belong to a novel class of regulatory determinants which are small non-coding RNAs with vital roles in regulating gene expression that also play a role in many human diseases. In this review we summarize miRNAs which have been shown to govern thermogenic, i.e. brite or brown, adipocyte recruitment and physiology. Notably, most miRNAs in this context have so far been characterized solely in mice, revealing a great demand for more human studies. As in the context of other diseases, RNA-based therapeutics have meanwhile entered clinical trials, further exploring the functions of miRNAs in brown and white adipose tissues could result in novel therapeutic approaches to treat obesity and its follow-up complications. PMID:25408843

  20. Body composition changes and inhibition of fat development in vivo implicates androgen in regulation of stem cell lineage allocation

    PubMed Central

    Semirale, Anthony A.; Zhang, Xiaowei; Wiren, Kristine M.

    2011-01-01

    Androgens regulate body composition in youth and declining testosterone that occurs with aging is associated with muscle wasting, increased fat mass and osteopenia. Transgenic mice with targeted androgen receptor (AR) overexpression in mesenchymal stem cells (MSC) were generated to explore the role of androgen signaling in the regulation of body composition. Transgenic males, but not females, were shorter and have reduced body weight and visceral fat accumulation. Dual energy x-ray absorptiometry (DXA) revealed significant reductions in fat mass with a reciprocal increase in lean mass, yet no difference in food consumption or locomotor activity was observed. Adipose tissue weight was normal in brown fat but reduced in both gonadal and perirenal depots, and reduced hyperplasia was observed with smaller adipocyte size in visceral and subcutaneous white adipose tissue. Although serum leptin, adiponectin, triglyceride, and insulin levels were no different between the genotypes, intraperitoneal glucose tolerance testing showed improved glucose clearance in transgenic males. High levels of the AR transgene are detected in MSCs but not in mature fat tissue. Reduced fibroblast colony forming units indicate fewer progenitor cells resident in the marrow in vivo. Precocious expression of GLUT4, PPARγ and C/EBPα was observed in proliferating precursor cultures from transgenic mice compared to controls. In more mature cultures, there was little difference between the genotypes. We propose a mechanism where enhanced androgen sensitivity can alter lineage commitment in vivo to reduce progenitor number and fat development, while increasing the expression of key factors to promote smaller adipocytes with improved glucose clearance. PMID:21381083

  1. β-1,3-Glucans are components of brown seaweed (Phaeophyceae) cell walls.

    PubMed

    Raimundo, Sandra Cristina; Pattathil, Sivakumar; Eberhard, Stefan; Hahn, Michael G; Popper, Zoë A

    2017-03-01

    LAMP is a cell wall-directed monoclonal antibody (mAb) that recognizes a β-(1,3)-glucan epitope. It has primarily been used in the immunolocalization of callose in vascular plant cell wall research. It was generated against a brown seaweed storage polysaccharide, laminarin, although it has not often been applied in algal research. We conducted in vitro (glycome profiling of cell wall extracts) and in situ (immunolabeling of sections) studies on the brown seaweeds Fucus vesiculosus (Fucales) and Laminaria digitata (Laminariales). Although glycome profiling did not give a positive signal with the LAMP mAb, this antibody clearly detected the presence of the β-(1,3)-glucan in situ, showing that this epitope is a constituent of these brown algal cell walls. In F. vesiculosus, the β-(1,3)-glucan epitope was present throughout the cell walls in all thallus parts; in L. digitata, the epitope was restricted to the sieve plates of the conductive elements. The sieve plate walls also stained with aniline blue, a fluorochrome used as a probe for callose. Enzymatic digestion with an endo-β-(1,3)-glucanase removed the ability of the LAMP mAb to label the cell walls. Thus, β-(1,3)-glucans are structural polysaccharides of F. vesiculosus cell walls and are integral components of the sieve plates in these brown seaweeds, reminiscent of plant callose.

  2. An Efficient Method to Obtain Dedifferentiated Fat Cells.

    PubMed

    Taniguchi, Hiroaki; Kazama, Tomohiko; Hagikura, Kazuhiro; Yamamoto, Chii; Kazama, Minako; Nagaoka, Yuki; Matsumoto, Taro

    2016-07-15

    Tissue engineering and cell therapy hold great promise clinically. In this regard, multipotent cells, such as mesenchymal stem cells (MSCs), may be used therapeutically, in the near future, to restore function to damaged organs. Nevertheless, several technical issues, including the highly invasive procedure of isolating MSCs and the inefficiency surrounding their amplification, currently hamper the potential clinical use of these therapeutic modalities. Herein, we introduce a highly efficient method for the generation of dedifferentiated fat cells (DFAT), MSC-like cells. Interestingly, DFAT cells can be differentiated into several cell types including adipogenic, osteogenic, and chondrogenic cells. Although other groups have previously presented various methods for generating DFAT cells from mature adipose tissue, our method allows us to produce DFAT cells more efficiently. In this regard, we demonstrate that DFAT culture medium (DCM), supplemented with 20% FBS, is more effective in generating DFAT cells than DMEM, supplemented with 20% FBS. Additionally, the DFAT cells produced by our cell culture method can be redifferentiated into several tissue types. As such, a very interesting and useful model for the study of tissue dedifferentiation is presented.

  3. Cell-autonomous activation of Hedgehog signaling inhibits brown adipose tissue development.

    PubMed

    Nosavanh, LaGina; Yu, Da-Hai; Jaehnig, Eric J; Tong, Qiang; Shen, Lanlan; Chen, Miao-Hsueh

    2015-04-21

    Although recent studies have shown that brown adipose tissue (BAT) arises from progenitor cells that also give rise to skeletal muscle, the developmental signals that control the formation of BAT remain largely unknown. Here, we show that brown preadipocytes possess primary cilia and can respond to Hedgehog (Hh) signaling. Furthermore, cell-autonomous activation of Hh signaling blocks early brown-preadipocyte differentiation, inhibits BAT formation in vivo, and results in replacement of neck BAT with poorly differentiated skeletal muscle. Finally, we show that Hh signaling inhibits BAT formation partially through up-regulation of chicken ovalbumin upstream promoter transcription factor II (COUP-TFII). Taken together, our studies uncover a previously unidentified role for Hh as an inhibitor of BAT development.

  4. GLUTATHIONE AND METALLOTHIONEIN STATUS IN AN ACUTE RESPONSE BY MERCENARIA MERCENARIA BROWN CELLS TO COPPER IN VIVO

    EPA Science Inventory

    Red glands of Mercenaria mercenaria comprise brown cells that accumulate, detoxify, and excrete copper. Brown cell involvement in metal detoxification is due in part to endogenous glutathione (GSH) and metallothionein (MT).The intent of this study was to test the hypotheses that ...

  5. IN VIVO METALLATHIONEIN AND GLUTATHIONE STATUS IN AN ACUTE REPONSE TO CADMINUM IN MERCENARIA MERCENARIA BROWN CELLS

    EPA Science Inventory

    Brown cells that are found in the red glands of Mercenaria mercenaria accumulate, detoxify and excrete cadmium. Brown cell involvement in metal detoxification was due in part to endogenous glutathione (GSH) and protein sulfhydryl. Metallothionein (MT) and GSH have been shown to p...

  6. Characteristics and multipotency of equine dedifferentiated fat cells

    PubMed Central

    MURATA, Daiki; YAMASAKI, Atsushi; MATSUZAKI, Shouta; SUNAGA, Takafumi; FUJIKI, Makoto; TOKUNAGA, Satoshi; MISUMI, Kazuhiro

    2016-01-01

    ABSTRACT Dedifferentiated fat (DFAT) cells have been shown to be multipotent, similar to mesenchymal stem cells (MSCs). In this study, we aimed to establish and characterize equine DFAT cells. Equine adipocytes were ceiling cultured, and then dedifferentiated into DFAT cells by the seventh day of culture. The number of DFAT cells was increased to over 10 million by the fourth passage. Flow cytometry of DFAT cells showed that the cells were strongly positive for CD44, CD90, and major histocompatibility complex (MHC) class I; moderately positive for CD11a/18, CD105, and MHC class II; and negative for CD34 and CD45. Moreover, DFAT cells were positive for the expression of sex determining region Y-box 2 as a marker of multipotency. Finally, we found that DFAT cells could differentiate into osteogenic, chondrogenic, and adipogenic lineages under specific nutrient conditions. Thus, DFAT cells could have clinical applications in tissue regeneration, similar to MSCs derived from adipose tissue. PMID:27330399

  7. The possible FAT1-mediated apoptotic pathways in porcine cumulus cells.

    PubMed

    Wu, Xinhui; Fu, Yao; Sun, Xulei; Liu, Chang; Chai, Menglong; Chen, Chengzhen; Dai, Lisheng; Gao, Yan; Jiang, Hao; Zhang, Jiabao

    2017-01-01

    Porcine cumulus cells are localized around oocytes and act as a specific type of granulosa that plays essential roles in the development and maturation of oocytes, the development and atresia of follicles, and the development of embryos. Studies of FAT1 have demonstrated its functions in cell-cell contact, actin dynamics, and cell growth suppression. To understand whether the FAT1 gene affects the apoptosis of porcine cumulus cells and to elucidate the mechanism of this potential action, FAT1 was knocked down using RNA interference. The lack of FAT1 resulted in stable expression of CTNNB, enhanced expression of cleaved CASP3, but decreased the BCL2/BAX ratios at both the mRNA and protein levels. These results indicated that FAT1 inhibited porcine cumulus cell apoptosis via different pathways. Taken together, these data provide new insights into the mechanisms of the association between FAT1 and porcine cumulus cell apoptosis.

  8. Enhanced stability and polyadenylation of select mRNAs support rapid thermogenesis in the brown fat of a hibernator.

    PubMed

    Grabek, Katharine R; Diniz Behn, Cecilia; Barsh, Gregory S; Hesselberth, Jay R; Martin, Sandra L

    2015-01-27

    During hibernation, animals cycle between torpor and arousal. These cycles involve dramatic but poorly understood mechanisms of dynamic physiological regulation at the level of gene expression. Each cycle, Brown Adipose Tissue (BAT) drives periodic arousal from torpor by generating essential heat. We applied digital transcriptome analysis to precisely timed samples to identify molecular pathways that underlie the intense activity cycles of hibernator BAT. A cohort of transcripts increased during torpor, paradoxical because transcription effectively ceases at these low temperatures. We show that this increase occurs not by elevated transcription but rather by enhanced stabilization associated with maintenance and/or extension of long poly(A) tails. Mathematical modeling further supports a temperature-sensitive mechanism to protect a subset of transcripts from ongoing bulk degradation instead of increased transcription. This subset was enriched in a C-rich motif and genes required for BAT activation, suggesting a model and mechanism to prioritize translation of key proteins for thermogenesis.

  9. Brown adipocyte differentiation is regulated by hedgehog signaling during development

    Technology Transfer Automated Retrieval System (TEKTRAN)

    During development, brown fat tissue arises from mesenchymal precursor cells under the control of signaling networks that are not yet well understood. The Hedgehog (Hh) signaling pathway is one of the major signaling pathways that regulate mesenchymal cell fate. However, whether the Hh pathway contr...

  10. Mitochondrial Hormesis links nutrient restriction to improved metabolism in fat cell.

    PubMed

    Lettieri Barbato, Daniele; Tatulli, Giuseppe; Aquilano, Katia; Ciriolo, Maria R

    2015-10-01

    Fasting promotes longevity by reprogramming metabolic and stress resistance pathways. However, although the impact on adipose tissue physiology through hormonal inputs is well established, the direct role of fasting on adipose cells is poorly understood. Herein we show that white and beige adipocytes, as well as mouse epididymal and subcutaneous adipose depots, respond to nutrient scarcity by acquiring a brown-like phenotype. Indeed, they improve oxidative metabolism through modulating the expression of mitochondrial- and nuclear-encoded oxidative phosphorylation genes as well as mitochondrial stress defensive proteins (UCP1, SOD2). Such adaptation is placed in a canonical mitohormetic response that proceeds via mitochondrial reactive oxygen species ((mt)ROS) production and redistribution of FoxO1 transcription factor into nucleus. Nuclear FoxO1 ((n)FoxO1) mediates retrograde communication by inducing the expression of mitochondrial oxidative and stress defensive genes. Collectively, our findings describe an unusual white/beige fat cell response to nutrient availability highlighting another health-promoting mechanism of fasting.

  11. Activation of rat intestinal mucosal mast cells by fat absorption.

    PubMed

    Ji, Yong; Sakata, Yasuhisa; Yang, Qing; Li, Xiaoming; Xu, Min; Yoder, Stephanie; Langhans, Wolfgang; Tso, Patrick

    2012-06-01

    Previous studies have linked certain types of gut mucosal immune cells with fat intake. We determined whether fat absorption activates intestinal mucosal mast cells (MMC), a key component of the gut mucosal immune system. Conscious intestinal lymph fistula rats were used. The mesenteric lymph ducts were cannulated, and the intraduodenal (i.d.) tubes were installed for the infusion of Liposyn II 20% (an intralipid emulsion). Lymphatic concentrations of histamine, rat MMC protease II (RMCPII), a specific marker of rat intestinal MMC degranulation, and prostaglandin D(2) (PGD(2)) were measured by ELISA. Intestinal MMC degranulation was visualized by immunofluorescent microscopy of jejunum sections taken at 1 h after Liposyn II gavage. Intraduodenal bolus infusion of Liposyn II 20% (4.4 kcal/3 ml) induced approximately a onefold increase in lymphatic histamine and PGD(2), ∼20-fold increase in lymphatic RMCPII, but only onefold increase in peripheral serum RMCPII concentrations. Release of RMCPII into lymph increased dose dependently with the amount of lipid fed. In addition, i.d. infusion of long-chain triacylglycerol trilinolein (C18:2 n-6, the major composite in Liposyn II) significantly increased the lymphatic RMCPII concentration, whereas medium-chain triacylglycerol tricaprylin (C8:0) did not alter lymph RMCPII secretion. Immunohistochemistry image revealed the degranulation of MMC into lamina propria after lipid feeding. These novel findings indicate that intestinal MMC are activated and degranulate to release MMC mediators to the circulation during fat absorption. This action of fatty acid is dose and chain length dependent.

  12. Tbx18-dependent differentiation of brown adipose tissue-derived stem cells toward cardiac pacemaker cells.

    PubMed

    Chen, Lei; Deng, Zi-Jun; Zhou, Jian-Sheng; Ji, Rui-Juan; Zhang, Xi; Zhang, Chuan-Sen; Li, Yu-Quan; Yang, Xiang-Qun

    2017-04-05

    A cell-sourced biological pacemaker is a promising therapeutic approach for sick sinus syndrome (SSS) or severe atrial ventricular block (AVB). Adipose tissue-derived stem cells (ATSCs), which are optimal candidate cells for possible use in regenerative therapy for acute or chronic myocardial injury, have the potential to differentiate into spontaneous beating cardiomyocytes. However, the pacemaker characteristics of the beating cells need to be confirmed, and little is known about the underlying differential mechanism. In this study, we found that brown adipose tissue-derived stem cells (BATSCs) in mice could differentiate into spontaneous beating cells in 15% FBS Dulbecco's modified Eagle's medium (DMEM) without additional treatment. Subsequently, we provide additional evidence, including data regarding ultrastructure, protein expression, electrophysiology, and pharmacology, to support the differentiation of BATSCs into a cardiac pacemaker phenotype during the course of early cultivation. Furthermore, we found that silencing Tbx18, a key transcription factor in the development of pacemaker cells, terminated the differentiation of BATSCs into a pacemaker phenotype, suggesting that Tbx18 is required to direct BATSCs toward a cardiac pacemaker fate. The expression of Tbx3 and shox2, the other two important transcription factors in the development of pacemaker cells, was decreased by silencing Tbx18, which suggests that Tbx18 mediates the differentiation of BATSCs into a pacemaker phenotype via these two downstream transcription factors.

  13. Life in the fat lane: seasonal regulation of insulin sensitivity, food intake, and adipose biology in brown bears.

    PubMed

    Rigano, K S; Gehring, J L; Evans Hutzenbiler, B D; Chen, A V; Nelson, O L; Vella, C A; Robbins, C T; Jansen, H T

    2016-12-16

    Grizzly bears (Ursus arctos horribilis) have evolved remarkable metabolic adaptations including enormous fat accumulation during the active season followed by fasting during hibernation. However, these fluctuations in body mass do not cause the same harmful effects associated with obesity in humans. To better understand these seasonal transitions, we performed insulin and glucose tolerance tests in captive grizzly bears, characterized the annual profiles of circulating adipokines, and tested the anorectic effects of centrally administered leptin at different times of the year. We also used bear gluteal adipocyte cultures to test insulin and beta-adrenergic sensitivity in vitro. Bears were insulin resistant during hibernation but were sensitive during the spring and fall active periods. Hibernating bears remained euglycemic, possibly due to hyperinsulinemia and hyperglucagonemia. Adipokine concentrations were relatively low throughout the active season but peaked in mid-October prior to hibernation when fat content was greatest. Serum glycerol was highest during hibernation, indicating ongoing lipolysis. Centrally administered leptin reduced food intake in October, but not in August, revealing seasonal variation in the brain's sensitivity to its anorectic effects. This was supported by strong phosphorylated signal transducer and activator of transcription 3 labeling within the hypothalamus of hibernating bears; labeling virtually disappeared in active bears. Adipocytes collected during hibernation were insulin resistant when cultured with hibernation serum but became sensitive when cultured with active season serum. Heat treatment of active serum blocked much of this action. Clarifying the cellular mechanisms responsible for the physiology of hibernating bears may inform new treatments for metabolic disorders.

  14. Brown fat thermogenesis in cold-acclimated rats is not abolished by the suppression of thyroid function.

    PubMed

    Zaninovich, Angel A; Raíces, Marcela; Rebagliati, Inés; Ricci, Conrado; Hagmüller, Karl

    2002-09-01

    The effects of long-term cold exposure on brown adipose tissue (BAT) thermogenesis in hypothyroid rats have been examined. Thyroid ablation was performed in normal rats after 2 mo of exposure to 4 degrees C, when BAT hypertrophy and thermogenic activity were maximal. After ablation, hypothyroid and normal controls remained in the cold for 2 additional months. At the end of the 4-mo cold exposure, all untreated hypothyroid rats were alive, had normal body temperature, and had gained an average 12.8% more weight than normal controls. Long-term cold exposure of hypothyroid rats markedly increased BAT weight, mitochondrial proteins, uncoupling protein (UCP)-1, mRNA for UCP-1, and oxygen consumption to levels similar to those seen in cold-exposed normal rats. The results indicate that thyroid hormones are required for increased thermogenic capacity to occur as an adaptation to long-term cold exposure. However, cold adaptation can be maintained in the absence of thyroid hormone.

  15. Enhanced stability and polyadenylation of select mRNAs support rapid thermogenesis in the brown fat of a hibernator

    PubMed Central

    Grabek, Katharine R; Diniz Behn, Cecilia; Barsh, Gregory S; Hesselberth, Jay R; Martin, Sandra L

    2015-01-01

    During hibernation, animals cycle between torpor and arousal. These cycles involve dramatic but poorly understood mechanisms of dynamic physiological regulation at the level of gene expression. Each cycle, Brown Adipose Tissue (BAT) drives periodic arousal from torpor by generating essential heat. We applied digital transcriptome analysis to precisely timed samples to identify molecular pathways that underlie the intense activity cycles of hibernator BAT. A cohort of transcripts increased during torpor, paradoxical because transcription effectively ceases at these low temperatures. We show that this increase occurs not by elevated transcription but rather by enhanced stabilization associated with maintenance and/or extension of long poly(A) tails. Mathematical modeling further supports a temperature-sensitive mechanism to protect a subset of transcripts from ongoing bulk degradation instead of increased transcription. This subset was enriched in a C-rich motif and genes required for BAT activation, suggesting a model and mechanism to prioritize translation of key proteins for thermogenesis. DOI: http://dx.doi.org/10.7554/eLife.04517.001 PMID:25626169

  16. Mmp1 and Mmp2 cooperatively induce Drosophila fat body cell dissociation with distinct roles.

    PubMed

    Jia, Qiangqiang; Liu, Yang; Liu, Hanhan; Li, Sheng

    2014-12-18

    During Drosophila metamorphosis, the single-cell layer of fat body tissues gradually dissociates into individual cells. Via a fat body-specific RNAi screen in this study, we found that two matrix metalloproteinases (MMPs), Mmp1 and Mmp2, are both required for fat body cell dissociation. As revealed through a series of cellular, biochemical, molecular, and genetic experiments, Mmp1 preferentially cleaves DE-cadherin-mediated cell-cell junctions, while Mmp2 preferentially degrades basement membrane (BM) components and thus destroy cell-BM junctions, resulting in the complete dissociation of the entire fat body tissues into individual cells. Moreover, several genetic interaction experiments demonstrated that the roles of Mmp1 and Mmp2 in this developmental process are cooperative. In conclusion, Mmp1 and Mmp2 induce fat body cell dissociation during Drosophila metamorphosis in a cooperative yet distinct manner, a finding that sheds light on the general mechanisms by which MMPs regulate tissue remodeling in animals.

  17. Technical note: Isolation and characterization of ovine brown adipocyte precursor cells.

    PubMed

    Ma, X; Hou, Y Q; Dahanayaka, S; Satterfield, M C; Burghardt, R C; Bazer, F W; Wu, G

    2015-05-01

    Brown adipose tissue (BAT) plays a critical role in regulating body temperature in newborn lambs. Availability of a stable BAT cell line would be invaluable for biochemical studies to elucidate cellular and molecular mechanisms responsible for nutritional regulation of fetal BAT growth and development. Ovine brown adipocyte precursor cells (BAPC) were isolated from fetal lambs at d 90 of gestation and cultured to establish a stable cell line. These cells were characterized by adipogenic differentiation and expression of a hallmark gene, (). The BAPC doubled every 24 h. After a 9-d induction with a serum-free Dulbecco's modified Eagle Ham/F12 medium, BAPC differentiated into brown adipocytes with large lipid droplets. The differentiation medium induced expression of mRNA and protein in BAPC. Furthermore, after BAPC were passaged 30 times, they maintained similar cell morphology, the potential for adipogenic differentiation, and the ability to express . Taken together, we have established a stable ovine BAPC cell line for studying nutritional regulation of BAT growth and development in the fetus.

  18. Application of dedifferentiated fat cells for periodontal tissue regeneration.

    PubMed

    Sugawara, Atsunori; Sato, Soh

    2014-01-01

    Periodontal diseases result from inflammation by bacterial infection in plaques, leading to tooth loss. However, regenerative approaches with periodontal tissue regeneration by guided tissue regeneration and enamel matrix derivative are not yet well established. Tissue regeneration requires three factors: cells, scaffold, and growth factors. Dedifferentiated fat cells (DFATs) are pluripotent with the same differentiation capacities as mesenchymal stem cells (MSCs). Access to MSCs is limited, whereas donor cells for DFATs are abundant in adipose tissues and can be non-invasively obtained. Therefore, we tested DFATs as a new source for periodontal tissue regeneration in an experimental periodontal tissue loss model in rats by transplanting DFATs on an atelocollagen scaffold using DFATs isolated from Sprague-Dawley (SD) rats expressing green fluorescent protein (GFP). GFP-DFAT cells were transplanted on the palatal side of the upper left first molar in SD rats and detected by H&E staining, GFP, and proliferating cell nuclear antigen (PCNA) expression. DFAT differentiation was also evaluated in three-dimensional cultures. GFP positive cells were detected in the regenerated tissue by the DFATs/scaffold mixture at 4 weeks after transplantation, and PCNA-positive cells were significantly increased in the periodontal ligament along the new bone in the DFATs/scaffold group more than in the scaffold-only group, suggesting that DFATs differentiate in the same manner as MSCs and regenerate in the defective areas. Consistent with previous reports, DFATs differentiation was slower than that with stem cells. The present study demonstrates that DFATs are pluripotent and an effective new source of cells for periodontal tissue regeneration.

  19. The properties and extracellular location of 5'-nucleotidase of the rat fat-cell plasma membrane.

    PubMed Central

    Newby, A C; Luzio, J P; Hales, C N

    1975-01-01

    1. A phosphohydrolase specific for 5'-nucleotides was characterized by using a particulate fraction from isolated fat-cells. 2. The activity of intact cells towards 5'-AMP was studied. 3. The activity in either situation had the same KM for AMP (45 muM) and was inhibited by low concentrations of ATP (less than 50 muM), but less potently by the ATP analogues AMP-P(CH2)P(adenylyl (beta gamma-methylene)diphosphonate) and AMP-P)NH)P (adenylylimidodiphosphate). 4. Homogenization of intact fat-cells caused no increase in activity and at least 85% of the activity was recovered in the particulate preparation. 5. The preparation of fat-cells used in this work was not freely permeable to AMP. 6. The ability of intact fat-cells to hydrolyse AMP implies that 5'-nucleotidase is an ectoenzyme in fat-cells. 7. Concentrations of ATP 100 times lower than intracellular concentrations inhibit the enzyme when added extracellularly to intact fat-cells, implying that this effect is also medicated at the extracellular face of the membrane. 8. Antibodies raised to whole liver cells and whole fat-cells inhibit 5'-nucleotidase in intact cells. 9. Incubation of intact fat-cells with adrenaline (1 mug/ml) or insulin (50 mui.u./ml) failed to alter the KM or Vmax. of the enzyme. PMID:167725

  20. Pre-germinated brown rice prevented high fat diet induced hyperlipidemia through ameliorating lipid synthesis and metabolism in C57BL/6J mice

    PubMed Central

    Shen, Kuo-Ping; Hao, Chi-Long; Yen, Hsueh-Wei; Chen, Chun-Yen; Chen, Jia-Hao; Chen, Fu-Chih; Lin, Hui-Li

    2016-01-01

    Pre-germinated brown rice (PGBR) can ameliorate hyperlipidemia, but the action mechanism is not clear. We focus the mechanisms of PGBR prevented hyperlipidemia. Six-week-old mice were divided into: standard-regular diet (SRD), high-fat diet (HFD) and HFD with PGBR (HFD + PGBR) groups for 16 weeks. The HFD group has higher concentrations of TG, TC, HDL and Non-HDL in the blood, and a higher atherosclerosis index (AI). The TG levels in the liver, and TG, bile acid levels in the feces were enhanced; and the total adipocytokines level in adipose tissue was reduced. The HFD group had higher protein expressions of SREBP-1, SCD-1, FAS, LDLR, and CYP7α1 in the liver. Moreover, the greater expressions of SREBP-1, SCD-1, FAS and the less expressions of PPAR-α and adiponectin were in adipose tissue. In the HFD + PGBR group, the PGBR regulated the levels of TG, TC, HDL, Non-HDL, AI and adipocytokines. PGBR increased more cholesterol and bile acid exhaust in feces. The SREBP-1, SCD-1, FAS, HMGCR, LDLR, CYP7α1 and PPAR-α proteins in the liver; and the SREBP-1, SCD-1, FAS, PPAR-α and adiponectin proteins in adipose tissue were reversed by PGBR. Taken together, PGBR can improve lipid synthesis and metabolism, and we suggest PGBR is a recommendable food for controlling hyperlipidemia. PMID:27499577

  1. Of mice and men: novel insights regarding constitutive and recruitable brown adipocytes

    PubMed Central

    Townsend, K L; Tseng, Y-H

    2015-01-01

    Recently, there has been great attention given to the possibility of combating obesity by targeting brown fat activity or increasing differentiation of brown adipocytes in white fat depots through a process termed ‘browning'. Sympathetic innervation of brown and white adipose tissues provides adrenergic input that drives thermogenesis and regulates fatty acid metabolism, as well as stimulating adipogenesis of recruitable brown adipocyte tissue (rBAT, also known as beige or brite) in white fat. Other factors acting in an endocrine or autocrine/paracrine manner in adipose tissue may also stimulate browning. There have been significant recent advances in understanding the mechanisms of increasing adipose tissue energy expenditure, as well as how brown adipocytes appear in white fat depots, including via de novo adipogenesis from tissue precursor cells. In this article, we integrate this new knowledge with a historical perspective on the discovery of ‘browning'. We also provide an overview of constitutive BAT vs rBAT in mouse and human. PMID:27152169

  2. Synthesis of mitochondrial uncoupling protein in brown adipocytes differentiated in cell culture

    SciTech Connect

    Kopecky, J.; Baudysova, M.; Zanotti, F.; Janikova, D.; Pavelka, S.; Houstek, J. )

    1990-12-25

    In order to characterize the biogenesis of unique thermogenic mitochondria of brown adipose tissue, differentiation of precursor cells isolated from mouse brown adipose tissue was studied in cell culture. Synthesis of mitochondrial uncoupling protein (UCP), F1-ATPase, and cytochrome oxidase was examined by L-(35S)methionine labeling and immunoblotting. For the first time, synthesis of physiological amounts of the UCP, a key and tissue-specific component of thermogenic mitochondria, was observed in cultures at about confluence (day 6), indicating that a complete differentiation of brown adipocytes was achieved in vitro. In postconfluent cells (day 8) the content of UCP decreased rapidly, in contrast to some other mitochondrial proteins (beta subunit of F1-ATPase, cytochrome oxidase). In these cells, it was possible, by using norepinephrine, to induce specifically the synthesis of the UCP but not of F1-ATPase or cytochrome oxidase. The maximal response was observed at 0.1 microM norepinephrine and the synthesis of UCP remained activated for at least 24 h. Detailed analysis revealed a major role of the beta-adrenergic receptors and elevated intracellular concentration of cAMP in stimulation of UCP synthesis. A quantitative recovery of the newly synthesized UCP in the mitochondrial fraction indicated completed biogenesis of functionally competent thermogenic mitochondria.

  3. Microbiota depletion promotes browning of white adipose tissue and reduces obesity

    PubMed Central

    Chevalier, Claire; Stojanović, Ozren; Colin, Didier J.; Stevanović, Ana; Veyrat-Durebex, Christelle; Tarallo, Valentina; Rigo, Dorothée; Germain, Stéphane; Ilievska, Miroslava; Montet, Xavier; Seimbille, Yann; Hapfelmeier, Siegfried; Trajkovski, Mirko

    2015-01-01

    Brown adipose tissue (BAT) promotes a lean and healthy phenotype and improves insulin sensitivity1. In response to cold or exercise brown fat cells also emerge in the white adipose tissue (named beige cells), a process known as browning2,3,4. Here, we show that the development of functional beige fat is promoted by microbiota depletion either by antibiotic treatment or in germ-free mice within the inguinal subcutaneous and perigonadal visceral adipose tissues (ingSAT and pgVAT, respectively). This leads to improved glucose tolerance, insulin sensitivity and decreased white fat and adipocyte size in lean mice and obese leptin-deficient (ob/ob) and high fat diet (HFD)-fed mice. These metabolic improvements are mediated by eosinophil infiltration and enhanced type 2 cytokine signaling and M2 macrophage polarization in the subcutaneous white fat depots of microbiota-depleted animals. The metabolic phenotype and the browning of the subcutaneous fat are impaired by suppression of the type 2 signaling and are reversed by recolonization of the antibiotic-treated, or the germ-free mice with microbes. These results provide insight into microbiota-fat signaling axis and beige fat development in health and metabolic disease. PMID:26569380

  4. β-Aminoisobutyric Acid Induces Browning of White Fat and Hepatic β-oxidation and is Inversely Correlated with Cardiometabolic Risk Factors

    PubMed Central

    Roberts, Lee D.; Boström, Pontus; O’Sullivan, John F.; Schinzel, Robert T.; Lewis, Gregory D.; Dejam, Andre; Lee, Youn-Kyoung; Palma, Melinda J.; Calhoun, Sondra; Georgiadi, Anastasia; Chen, Ming-Huei; Ramachandran, Vasan S.; Larson, Martin G.; Bouchard, Claude; Rankinen, Tuomo; Souza, Amanda L.; Clish, Clary B.; Wang, Thomas J.; Estall, Jennifer L.; Soukas, Alexander A.; Cowan, Chad A.; Spiegelman, Bruce M.; Gerszten, Robert E.

    2014-01-01

    Summary The transcriptional co-activator peroxisome proliferator-activated receptor-gamma co-activator-1 α (PGC-1α) regulates metabolic genes in skeletal muscle, and contributes substantially to the response of muscle to exercise. Muscle specific PGC-1α transgenic expression and exercise both increase the expression of thermogenic genes within white adipose. How the PGC-1α mediated response to exercise in muscle conveys signals to other tissues remains incompletely defined. We employed a metabolic profiling approach to examine metabolites secreted from myocytes with forced expression of PGC-1α, and identified β-aminoisobutyric acid (BAIBA) as a novel small molecule myokine. BAIBA increases the expression of brown adipocyte-specific genes in white adipose tissue and fatty acid β-oxidation in hepatocytes both in vitro and in vivo through a PPARα mediated mechanism, induces a brown adipose-like phenotype in human pluripotent stem cells, and improves glucose homeostasis in mice. In humans, plasma BAIBA concentrations are increased with exercise and inversely associated with metabolic risk factors. BAIBA may thus contribute to exercise-induced protection from metabolic diseases. PMID:24411942

  5. β-Aminoisobutyric acid induces browning of white fat and hepatic β-oxidation and is inversely correlated with cardiometabolic risk factors.

    PubMed

    Roberts, Lee D; Boström, Pontus; O'Sullivan, John F; Schinzel, Robert T; Lewis, Gregory D; Dejam, Andre; Lee, Youn-Kyoung; Palma, Melinda J; Calhoun, Sondra; Georgiadi, Anastasia; Chen, Ming-Huei; Ramachandran, Vasan S; Larson, Martin G; Bouchard, Claude; Rankinen, Tuomo; Souza, Amanda L; Clish, Clary B; Wang, Thomas J; Estall, Jennifer L; Soukas, Alexander A; Cowan, Chad A; Spiegelman, Bruce M; Gerszten, Robert E

    2014-01-07

    The transcriptional coactivator peroxisome proliferator-activated receptor-gamma coactivator-1α (PGC-1α) regulates metabolic genes in skeletal muscle and contributes to the response of muscle to exercise. Muscle PGC-1α transgenic expression and exercise both increase the expression of thermogenic genes within white adipose. How the PGC-1α-mediated response to exercise in muscle conveys signals to other tissues remains incompletely defined. We employed a metabolomic approach to examine metabolites secreted from myocytes with forced expression of PGC-1α, and identified β-aminoisobutyric acid (BAIBA) as a small molecule myokine. BAIBA increases the expression of brown adipocyte-specific genes in white adipocytes and β-oxidation in hepatocytes both in vitro and in vivo through a PPARα-mediated mechanism, induces a brown adipose-like phenotype in human pluripotent stem cells, and improves glucose homeostasis in mice. In humans, plasma BAIBA concentrations are increased with exercise and inversely associated with metabolic risk factors. BAIBA may thus contribute to exercise-induced protection from metabolic diseases.

  6. In vivo sulfhydryl distribution in brown cells of Mercenaria mercenaria exposed to cadmium

    SciTech Connect

    Zaroogian, G.

    1995-12-31

    Brown cells are found in the red glands of Mercenaria mercenaria (Bivalvia) and have a role in detoxification. Brown cell involvement in metal detoxification is due in part to endogenous glutathione (GSH) and protein bound sulfhydryl (PBSH). During treatment of Mercenaria with 0.5 and 1.0 ppm Cd{sup 2+}, brown cells were analyzed for total sulfhydryl (TSH), PBSH, non-protein bound sulfhydryl (NPSH) and GSH after 0.25, 1, 2, 3, 6, 12 and 20 days. Trend analyses indicated that treatment with 0.5 ppm Cd{sup 2+} caused a continuous increase in PBSH/TSH, whereas NPSH/TSH did not appear to change during 20 days treatment. The GSH/NPSH ratio increased significantly (P<0.01) for 6 days, followed by a significant (P<0.01) continuous decrease to day 20. Treatment with 1.0 ppm Cd{sup 2+} caused an increase in NPSH/TSH during the first 3 days, after which the ratio remained fairly constant to day 20, whereas PBSH/TSH decreased today 2, increased to day 3 and remained unchanged to day 20. The GSH/NPSH ratio remained fairly constant for the first 12 days after which it increased significantly (P<0.01). Histopathological examination after treatment with 1.0 ppm Cd 2{sup +} indicated darkening of the lysosomes during the first 2 days, followed by extensive brown cell sloughing into the tubule lumen and the abundance of small lysosomes at day 3. Sloughing and small lysosome formation continued to a lesser extent to day 20 when granulocyte infiltration and necrosis of the intertubular connective tissue occurred. The data indicate that GSH is more resistant to fluctuations than PBSH which suggests a more rapid synthesis or turnover rate for GSH. The ratio of GSH to PBSH has potential for a biomarker of cadmium exposure and health of Mercenaria.

  7. [Morphofunctional changes of dendritic cells induced by sulfated polysaccharides of brown algae].

    PubMed

    Makarenkova, I D; Akhmatova, N K; Ermakova, S P; Besednova, N N

    2017-01-01

    The effects of various sulfated polysaccharides of brown algae Fucus evanescens, Saccharina cichorioides and Saccharina japonica on the morphofunctional changes of dendritic cells have been investigated using flow cytometry and phase-contrast microscopy. The dendritic cells are characterized by larger sizes, vacuolated cytoplasm, eccentrically located nucleus, and also by the presence of numerous cytoplasmic pseudopodia of various shapes. They express surface markers, indicating their maturation (CD83, CD11c, HLA-DR, CD86). Increased production of immunoregulatory (IL-12) and proinflammatory TNF-a, IL-6) cytokines (by dendritic cells polarizes the development of the Th-1 type immune response.

  8. Regulation of neuronal migration by Dchs1-Fat4 planar cell polarity

    PubMed Central

    Zakaria, Sana; Mao, Yaopan; Kuta, Anna; de Sousa, Catia Ferreira; Gaufo, Gary O.; McNeill, Helen; Hindges, Robert; Guthrie, Sarah

    2014-01-01

    Summary Planar-cell polarity (PCP) describes the polarisation of cell structures and behaviors within the plane of a tissue. PCP is essential for the generation of tissue architecture during embryogenesis and for post-natal growth and tissue repair, yet how it is oriented to coordinate cell polarity remains poorly understood [1]. In Drosophila, PCP is mediated via the Frizzled-Flamingo (Fz-PCP) and Dachsous-Fat (Fat-PCP) pathways [1-3]. Fz-PCP is conserved in vertebrates but an understanding in vertebrates of whether and how Fat-PCP polarizes cells, and its relationship to Fz-PCP signaling, is lacking. Mutations in human FAT4 and DCHS1 cause Van Maldergem syndrome, characterized by severe neuronal abnormalities indicative of altered neuronal migration [4]. Here, we investigate the role and mechanisms of Fat-PCP during neuronal migration using the murine facial branchiomotor neurons (FBM) as a model. We find that Fat4 and Dchs1, key components of Fat-PCP signaling, are expressed in complementary gradients and are required for the collective tangential migration of FBM and for their PCP. Fat4 and Dchs1 are required intrinsically within the FBM and extrinsically within the neuroepithelium. Remarkably, Fat-PCP and Fz-PCP regulate FBM migration along orthogonal axes. Disruption of the Dchs1 gradients by mosaic inactivation of Dchs1 alters FBM polarity and migration. This study implies that PCP in vertebrates can be regulated via gradients of Fat4 and Dchs1 expression, which establish intracellular polarity across FBM cells during their migration. Our results also identify Fat-PCP as a novel neuronal guidance system, and reveal that Fat-PCP and Fz-PCP can act along orthogonal axes. PMID:24998526

  9. Pre-germinated brown rice prevents high-fat diet induced hyperglycemia through elevated insulin secretion and glucose metabolism pathway in C57BL/6J strain mice

    PubMed Central

    Shen, Kuo-Ping; Hao, Chi-Long; Yen, Hsueh-Wei; Chen, Chun-Yen; Wu, Bin-Nan; Lin, Hui-Li

    2015-01-01

    This study investigated the effect and mechanism of pre-germinated brown rice (PGBR) prevented hyperglycemia in C57BL/6J mice fed high-fat-diet (HFD). Normal six-week-old mice were randomly divided into three groups. Group 1 was fed standard-regular-diet (SRD) and group 2 was fed HFD for 16 weeks. In group 3, the mice were fed a HFD with its carbohydrate replaced with PGBR for 16 weeks. Comparing the SRD and HFD groups, we found the HFD group had higher blood pressure, higher concentrations of blood glucose and HbA1c. The HFD group had less protein expression of insulin receptor (IR), insulin receptor substrate-1 (IRS-1), phosphatidylinositol-3-kinase (PI3K), glucose transporter-4 (GLUT-4) and glucokinase (GCK) and greater expression of glucogen synthase kinase (GSK) in skeletal muscle. The HFD group also had less expression of IR, serine/threonine kinase PI3K-linked protein kinase B (Akt/PKB), AMP-activated protein kinase (AMPK), GCK and peroxisome proliferator-activated receptor γ (PPARγ) in liver. In the HFD + PGBR group, the PGBR could reverse the disorders of blood pressure, blood glucose, HbA1c and increase insulin concentration. PGBR increased the IR, IRS-1, PI3K, Akt, GLUT-1 and GLUT-4 proteins, and ameliorated AMPK, GCK, GSK and PPARγ proteins. Together, PGBR prevented HFD-induced hyperglycemia through improving insulin levels, insulin receptor, glucose transporters and enhancing glucose metabolism. PMID:25834303

  10. Dynamics of cell wall assembly during early embryogenesis in the brown alga Fucus

    PubMed Central

    Torode, Thomas A.; Siméon, Amandine; Marcus, Susan E.; Jam, Murielle; Le Moigne, Marie-Anne; Duffieux, Delphine; Knox, J. Paul; Hervé, Cécile

    2016-01-01

    Zygotes from Fucus species have been used extensively to study cell polarization and rhizoid outgrowth, and in this model system cell wall deposition aligns with the establishment of polarity. Monoclonal antibodies are essential tools for the in situ analysis of cell wall glycans, and here we report the characteristics of six monoclonal antibodies to alginates (BAM6–BAM11). The use of these, in conjunction with monoclonal antibodies to brown algal sulfated fucans, has enabled the study of the developmental dynamics of the Fucus zygote cell walls. Young zygotes are spherical and all alginate epitopes are deposited uniformly following cellulose deposition. At germination, sulfated fucans are secreted in the growing rhizoid wall. The redistribution of cell wall epitopes was investigated during treatments that cause reorientation of the growth axis (change in light direction) or disrupt rhizoid development (arabinogalactan-protein-reactive Yariv reagent). Alginate modeling was drastically impaired in the latter, and both treatments cause a redistribution of highly sulfated fucan epitopes. The dynamics of cell wall glycans in this system have been visualized in situ for the first time, leading to an enhanced understanding of the early developmental mechanisms of Fucus species. These sets of monoclonal antibodies significantly extend the available molecular tools for brown algal cell wall studies. PMID:27811078

  11. Dynamics of cell wall assembly during early embryogenesis in the brown alga Fucus.

    PubMed

    Torode, Thomas A; Siméon, Amandine; Marcus, Susan E; Jam, Murielle; Le Moigne, Marie-Anne; Duffieux, Delphine; Knox, J Paul; Hervé, Cécile

    2016-11-01

    Zygotes from Fucus species have been used extensively to study cell polarization and rhizoid outgrowth, and in this model system cell wall deposition aligns with the establishment of polarity. Monoclonal antibodies are essential tools for the in situ analysis of cell wall glycans, and here we report the characteristics of six monoclonal antibodies to alginates (BAM6-BAM11). The use of these, in conjunction with monoclonal antibodies to brown algal sulfated fucans, has enabled the study of the developmental dynamics of the Fucus zygote cell walls. Young zygotes are spherical and all alginate epitopes are deposited uniformly following cellulose deposition. At germination, sulfated fucans are secreted in the growing rhizoid wall. The redistribution of cell wall epitopes was investigated during treatments that cause reorientation of the growth axis (change in light direction) or disrupt rhizoid development (arabinogalactan-protein-reactive Yariv reagent). Alginate modeling was drastically impaired in the latter, and both treatments cause a redistribution of highly sulfated fucan epitopes. The dynamics of cell wall glycans in this system have been visualized in situ for the first time, leading to an enhanced understanding of the early developmental mechanisms of Fucus species. These sets of monoclonal antibodies significantly extend the available molecular tools for brown algal cell wall studies.

  12. Beige differentiation of adipose depots in mice lacking prolactin receptor protects against high-fat-diet-induced obesity.

    PubMed

    Auffret, Julien; Viengchareun, Say; Carré, Nadège; Denis, Raphaël G P; Magnan, Christophe; Marie, Pierre-Yves; Muscat, Adeline; Fève, Bruno; Lombès, Marc; Binart, Nadine

    2012-09-01

    Stimulating conversion of white fat to metabolically active adipocytes (beige fat) constitutes a promising strategy against weight gain and its deleterious associated-disorders. We provide direct evidence that prolactin (PRL), best known for its actions on the mammary gland, plays a pivotal role in energy balance through the control of adipocyte differentiation and fate. Here we show that lack of prolactin receptor (PRLR) causes resistance to high-fat-diet-induced obesity due to enhanced energy expenditure and increased metabolic rate. Mutant mice displayed reduced fat mass associated with appearance of massive brown-like adipocyte foci in perirenal and subcutaneous but not in gonadal fat depots under a high-fat diet. Positron emission tomography imaging further demonstrated the occurrence of these thermogenic brown fat depots in adult mice, providing additional support for recruitable brown-like adipocytes (beigeing) in white fat depots. Consistent with the activation of brown adipose tissue, PRLR inactivation increases expression of master genes controlling brown adipocyte fate (PRDM16) and mitochondrial function (PGC1α, UCP1). Altered pRb/Foxc2 expression suggests that this PRL-regulated pathway may contribute to beige cell commitment. Together, these results provide direct genetic evidence that PRLR affects energy balance and metabolic adaptation in rodents via effects on brown adipose tissue differentiation and function.

  13. You Are What You Eat: Linking High-Fat Diet to Stem Cell Dysfunction and Tumorigenesis.

    PubMed

    Haller, Samantha; Jasper, Heinrich

    2016-05-05

    A high-fat diet is linked to elevated cancer risk, yet this link remains poorly understood. New studies in mice are now beginning to obtain mechanistic insight into how high-fat diets perturb stem cell function and cause cancers.

  14. Red Blood Cell Dysfunction Induced by High-Fat Diet

    PubMed Central

    Unruh, Dusten; Srinivasan, Ramprasad; Benson, Tyler; Haigh, Stephen; Coyle, Danielle; Batra, Neil; Keil, Ryan; Sturm, Robert; Blanco, Victor; Palascak, Mary; Franco, Robert S.; Tong, Wilson; Chatterjee, Tapan; Hui, David Y.; Davidson, W. Sean; Aronow, Bruce J.; Kalfa, Theodosia; Manka, David; Peairs, Abigail; Blomkalns, Andra; Fulton, David J.; Brittain, Julia E.; Weintraub, Neal L.; Bogdanov, Vladimir Y.

    2015-01-01

    Background High-fat diet (HFD) promotes endothelial dysfunction and proinflammatory monocyte activation, which contribute to atherosclerosis in obesity. We investigated whether HFD also induces the dysfunction of red blood cells (RBCs), which serve as a reservoir for chemokines via binding to Duffy antigen receptor for chemokines (DARC). Methods and Results A 60% HFD for 12 weeks, which produced only minor changes in lipid profile in C57/BL6 mice, markedly augmented the levels of monocyte chemoattractant protein-1 bound to RBCs, which in turn stimulated macrophage migration through an endothelial monolayer. Levels of RBC-bound KC were also increased by HFD. These effects of HFD were abolished in DARC−/− mice. In RBCs from HFD-fed wild-type and DARC−/− mice, levels of membrane cholesterol and phosphatidylserine externalization were increased, fostering RBC-macrophage inflammatory interactions and promoting macrophage phagocytosis in vitro. When labeled ex vivo and injected into wild-type mice, RBCs from HFD-fed mice exhibited ≈3-fold increase in splenic uptake. Finally, RBCs from HFD-fed mice induced increased macrophage adhesion to the endothelium when they were incubated with isolated aortic segments, indicating endothelial activation. Conclusions RBC dysfunction, analogous to endothelial dysfunction, occurs early during diet-induced obesity and may serve as a mediator of atherosclerosis. These findings may have implications for the pathogenesis of atherosclerosis in obesity, a worldwide epidemic. PMID:26467254

  15. Stage T3a renal cell carcinoma: staging accuracy of CT for sinus fat, perinephric fat or renal vein invasion

    PubMed Central

    Sokhi, H K; Mok, W Y

    2015-01-01

    Objective: To study the accuracy of CT for staging T3a (TNM 2009) renal cell carcinoma (RCC). Methods: Unenhanced and nephrographic phase CT studies of 117 patients (male:female = 82:35; age range, 21–86 years) with T1–T3a RCC were independently reviewed by 2 readers. The presence of sinus or perinephric fat, or renal vein invasion and tumour characteristics were noted. Results: Median (range) tumour size was 5.5 (0.9–19.0) cm; and 46 (39%), 16 (14%) and 55 (47%) tumours were pT1, pT2 and pT3a RCC, respectively. The sensitivity/specificity for sinus fat, perinephric fat and renal vein invasion were 71/79%, 83/76% and 59/93% (Reader 1) and 88/71%, 68/72% and 69/91% (Reader 2) with κ = 0.41, 0.43 and 0.61, respectively. Sinus fat invasion was seen in 47/55 (85%) cases with T3a RCC vs 16/55 (29%) and 33/55 (60%) for perinephric fat and renal vein invasion. Tumour necrosis, irregularity of tumour edge and direct tumour contact with perirenal fascia or sinus fat increased the odds of local invasion [odds ratio (OR), 2.5–3.7; p < 0.05; κ = 0.42–0.61]. Stage T3a tumours were centrally located (OR, 3.9; p = 0.0009). Conclusion: Stage T3a RCC was identified with a sensitivity of 59–88% and specificity of 71–93% (κ = 0.41–0.61). Sinus fat invasion was the most common invasive feature. Advances in knowledge: Centrally situated renal tumours with an irregular tumour edge, inseparable from sinus structures or the perirenal fascia and CT features of tumour necrosis should alert the reader to the possibility of Stage T3a RCC (OR, 2.5–3.9). PMID:25410425

  16. Application of cell co-culture system to study fat and muscle cells.

    PubMed

    Pandurangan, Muthuraman; Hwang, Inho

    2014-09-01

    Animal cell culture is a highly complex process, in which cells are grown under specific conditions. The growth and development of these cells is a highly unnatural process in vitro condition. Cells are removed from animal tissues and artificially cultured in various culture vessels. Vitamins, minerals, and serum growth factors are supplied to maintain cell viability. Obtaining result homogeneity of in vitro and in vivo experiments is rare, because their structure and function are different. Living tissues have highly ordered complex architecture and are three-dimensional (3D) in structure. The interaction between adjacent cell types is quite distinct from the in vitro cell culture, which is usually two-dimensional (2D). Co-culture systems are studied to analyze the interactions between the two different cell types. The muscle and fat co-culture system is useful in addressing several questions related to muscle modeling, muscle degeneration, apoptosis, and muscle regeneration. Co-culture of C2C12 and 3T3-L1 cells could be a useful diagnostic tool to understand the muscle and fat formation in animals. Even though, co-culture systems have certain limitations, they provide a more realistic 3D view and information than the individual cell culture system. It is suggested that co-culture systems are useful in evaluating the intercellular communication and composition of two different cell types.

  17. Fat4-Dchs1 signalling controls cell proliferation in developing vertebrae

    PubMed Central

    Kuta, Anna; Mao, Yaopan; Martin, Tina; Ferreira de Sousa, Catia; Whiting, Danielle; Zakaria, Sana; Crespo-Enriquez, Ivan; Evans, Philippa; Balczerski, Bartosz; Mankoo, Baljinder; Irvine, Kenneth D.

    2016-01-01

    The protocadherins Fat4 and Dchs1 act as a receptor-ligand pair to regulate many developmental processes in mice and humans, including development of the vertebrae. Based on conservation of function between Drosophila and mammals, Fat4-Dchs1 signalling has been proposed to regulate planar cell polarity (PCP) and activity of the Hippo effectors Yap and Taz, which regulate cell proliferation, survival and differentiation. There is strong evidence for Fat regulation of PCP in mammals but the link with the Hippo pathway is unclear. In Fat4−/− and Dchs1−/− mice, many vertebrae are split along the midline and fused across the anterior-posterior axis, suggesting that these defects might arise due to altered cell polarity and/or changes in cell proliferation/differentiation. We show that the somite and sclerotome are specified appropriately, the transcriptional network that drives early chondrogenesis is intact, and that cell polarity within the sclerotome is unperturbed. We find that the key defect in Fat4 and Dchs1 mutant mice is decreased proliferation in the early sclerotome. This results in fewer chondrogenic cells within the developing vertebral body, which fail to condense appropriately along the midline. Analysis of Fat4;Yap and Fat4;Taz double mutants, and expression of their transcriptional target Ctgf, indicates that Fat4-Dchs1 regulates vertebral development independently of Yap and Taz. Thus, we have identified a new pathway crucial for the development of the vertebrae and our data indicate that novel mechanisms of Fat4-Dchs1 signalling have evolved to control cell proliferation within the developing vertebrae. PMID:27381226

  18. Exchangeable and total calcium pools in mitochondria of rat epididymal fat-pads and isolated fat-cells. Role in the regulation of pyruvate dehydrogenase activity.

    PubMed

    Severson, D L; Denton, R M; Bridges, B J; Randle, P J

    1976-01-15

    1. Isolated fat-cells and intact epididymal fat-pads were incubated in medium containing 45Ca2+ and the incorporation of 45Ca into mitochondrial and extramitochondrial fractions was studied. Redistribution of 45Ca between these fractions was essentially prevented by the addition of EGTA [ethanedioxybis(ethylamine)tetra-acetate] and Ruthenium Red to the sucrose-based extraction medium. 2. Incorporation of 45Ca into mitochondrial fractions of both fat-cells and fat-pads was found to be complete within 2-5 min, suggesting that mitochondria contain a pool of calcium in rapid isotopic exchange with extracellular Ca2+. This pool was about 20 times larger in mitochondria within fat-cells than within fat-pads. In fat-cells, 45Ca incorporation into the mitochondrial fraction accounted for about 34% of the total 45Ca incorporation into cells after 20 min and about 50% of the total mitochondrial calcium content measured by atomic absorption; values in fat-pads were about 7 and 20% respectively.

  19. Receptor binding sites for atrial natriuretic factor are expressed by brown adipose tissue

    SciTech Connect

    Bacay, A.C.; Mantyh, C.R.; Vigna, S.R.; Mantyh, P.W. )

    1988-09-01

    To explore the possibility that atrial natriuretic factor (ANF) is involved in thermoregulation we used quantitative receptor autoradiography and homogenate receptor binding assays to identify ANF bindings sites in neonatal rat and sheep brown adipose tissue, respectively. Using quantitative receptor autoradiography were were able to localize high levels of specific binding sites for {sup 125}I-rat ANF in neonatal rat brown adipose tissue. Homogenate binding assays on sheep brown fat demonstrated that the radioligand was binding to the membrane fraction and that the specific binding was not due to a lipophilic interaction between {sup 125}I-rat ANF and brown fat. Specific binding of {sup 125}I-rat ANF to the membranes of brown fat cells was inhibited by unlabeled rat ANF with a Ki of 8.0 x 10(-9) M, but not by unrelated peptides. These studies demonstrate that brown fat cells express high levels of ANF receptor binding sites in neonatal rat and sheep and suggest that ANF may play a role in thermoregulation.

  20. Milk fat conjugated linoleic acid (CLA) inhibits growth of human mammary MCF-7 cancer cells.

    PubMed

    O'Shea, M; Devery, R; Lawless, F; Murphy, J; Stanton, C

    The relationship between growth and the antioxidant enzyme defence system in human MCF-7 (breast) cancer cells treated with bovine milk fat enriched with conjugated linoleic acid (CLA) was studied. Milk enriched in CLA was obtained from cows on pasture supplemented with full fat rapeseeds and full fat soyabeans (1). Cell number decreased up to 90% (p < 0.05) and lipid peroxidation increased 15-fold (p < 0.05) following incubation of MCF-7 cells for 8 days with increasing levels of milk fat yielding CLA concentrations between 16.9 and 22.6 ppm. Growth suppression and prooxidant effects of milk fat CLA were independent of the variable composition of the milk fat samples, suggesting that CLA was the active ingredient in milk fat responsible for the cytotoxic effect. Mixtures containing isomers of CLA (c9, t11-, t10, c12-, c11, t13- and minor amounts of other isomers) and linoleic acid (LA) at similar concentrations to the milk fat samples were as effective at inhibiting growth and stimulating peroxidation of MCF-7 cells as the milk fatty acids. Incubation of the cells with the c9, t11 CLA isomer (20 ppm) or the mixture of CLA isomers (20 ppm) for 8 days resulted in a 60% decrease (p < 0.05) in viability compared with untreated controls and was significantly (p < 0.05) more effective than incubation with the t10, c12 CLA isomer (20 ppm), which caused only a 15% decrease in cell numbers under similar conditions. A 25% increase (p < 0.05) in cell proliferation occurred when LA (20 ppm) alone was incubated with MCF-7 cells for 8 days. 14C-CLA was preferentially incorporated into the phospholipid fraction of the MCF-7 cell lipids in a dose-dependent manner and CLA accumulated in cell membranes more efficiently when the cells were incubated in the presence of milk fat than the c9, t11 synthetic CLA isomer. Superoxide dismutase (SOD), catalase and glutathione peroxidase (GPx) activities were induced in MCF-7 cells exposed to milk fat (containing 16.9-22.6 ppm CLA) over 8

  1. Mammary Fat of Breast Cancer: Gene Expression Profiling and Functional Characterization

    PubMed Central

    Chen, Fei; Fu, Ziyi; Yin, Hong; Lu, Xun; Yu, Jing; Lu, Cheng

    2014-01-01

    Mammary fat is the main composition of breast, and is the most probable candidate to affect tumor behavior because the fat produces hormones, growth factors and adipokines, a heterogeneous group of signaling molecules. Gene expression profiling and functional characterization of mammary fat in Chinese women has not been reported. Thus, we collected the mammary fat tissues adjacent to breast tumors from 60 subjects, among which 30 subjects had breast cancer and 30 had benign lesions. We isolated and cultured the stromal vascular cell fraction from mammary fat. The expression of genes related to adipose function (including adipogenesis and secretion) was detected at both the tissue and the cellular level. We also studied mammary fat browning. The results indicated that fat tissue close to malignant and benign lesions exhibited distinctive gene expression profiles and functional characteristics. Although the mammary fat of breast tumors atrophied, it secreted tumor growth stimulatory factors. Browning of mammary fat was observed and browning activity of fat close to malignant breast tumors was greater than that close to benign lesions. Understanding the diversity between these two fat depots may possibly help us improve our understanding of breast cancer pathogenesis and find the key to unlock new anticancer therapies. PMID:25291184

  2. Mammary fat of breast cancer: gene expression profiling and functional characterization.

    PubMed

    Wang, Fengliang; Gao, Sheng; Chen, Fei; Fu, Ziyi; Yin, Hong; Lu, Xun; Yu, Jing; Lu, Cheng

    2014-01-01

    Mammary fat is the main composition of breast, and is the most probable candidate to affect tumor behavior because the fat produces hormones, growth factors and adipokines, a heterogeneous group of signaling molecules. Gene expression profiling and functional characterization of mammary fat in Chinese women has not been reported. Thus, we collected the mammary fat tissues adjacent to breast tumors from 60 subjects, among which 30 subjects had breast cancer and 30 had benign lesions. We isolated and cultured the stromal vascular cell fraction from mammary fat. The expression of genes related to adipose function (including adipogenesis and secretion) was detected at both the tissue and the cellular level. We also studied mammary fat browning. The results indicated that fat tissue close to malignant and benign lesions exhibited distinctive gene expression profiles and functional characteristics. Although the mammary fat of breast tumors atrophied, it secreted tumor growth stimulatory factors. Browning of mammary fat was observed and browning activity of fat close to malignant breast tumors was greater than that close to benign lesions. Understanding the diversity between these two fat depots may possibly help us improve our understanding of breast cancer pathogenesis and find the key to unlock new anticancer therapies.

  3. Neuroprotective Effects of Germinated Brown Rice against Hydrogen Peroxide Induced Cell Death in Human SH-SY5Y Cells

    PubMed Central

    Ismail, Norsharina; Ismail, Maznah; Fathy, Siti Farhana; Musa, Siti Nor Asma; Imam, Mustapha Umar; Foo, Jhi Biau; Iqbal, Shahid

    2012-01-01

    The neuroprotective and antioxidative effects of germinated brown rice (GBR), brown rice (BR) and commercially available γ-aminobutyric acid (GABA) against cell death induced by hydrogen peroxide (H2O2) in human neuroblastoma SH-SY5Y cells have been investigated. Results show that GBR suppressed H2O2-mediated cytotoxicity and induced G0/G1 phase cell cycle arrest in SH-SY5Y cells. Moreover, GBR reduced mitochondrial membrane potential (MMP) and prevented phosphatidylserine (PS) translocation in SH-SY5Y cells, key features of apoptosis, and subsequent cell death. GBR exhibited better neuroprotective and antioxidative activities as compared to BR and GABA. These results indicate that GBR possesses high antioxidative activities and suppressed cell death in SH-SY5Y cells by blocking the cell cycle re-entry and apoptotic mechanisms. Therefore, GBR could be developed as a value added functional food to prevent neurodegenerative diseases caused by oxidative stress and apoptosis. PMID:22949825

  4. Neuroprotective effects of germinated brown rice against hydrogen peroxide induced cell death in human SH-SY5Y cells.

    PubMed

    Ismail, Norsharina; Ismail, Maznah; Fathy, Siti Farhana; Musa, Siti Nor Asma; Imam, Mustapha Umar; Foo, Jhi Biau; Iqbal, Shahid

    2012-01-01

    The neuroprotective and antioxidative effects of germinated brown rice (GBR), brown rice (BR) and commercially available γ-aminobutyric acid (GABA) against cell death induced by hydrogen peroxide (H(2)O(2)) in human neuroblastoma SH-SY5Y cells have been investigated. Results show that GBR suppressed H(2)O(2)-mediated cytotoxicity and induced G0/G1 phase cell cycle arrest in SH-SY5Y cells. Moreover, GBR reduced mitochondrial membrane potential (MMP) and prevented phosphatidylserine (PS) translocation in SH-SY5Y cells, key features of apoptosis, and subsequent cell death. GBR exhibited better neuroprotective and antioxidative activities as compared to BR and GABA. These results indicate that GBR possesses high antioxidative activities and suppressed cell death in SH-SY5Y cells by blocking the cell cycle re-entry and apoptotic mechanisms. Therefore, GBR could be developed as a value added functional food to prevent neurodegenerative diseases caused by oxidative stress and apoptosis.

  5. Controlled cellular energy conversion in brown adipose tissue thermogenesis

    NASA Technical Reports Server (NTRS)

    Horowitz, J. M.; Plant, R. E.

    1978-01-01

    Brown adipose tissue serves as a model system for nonshivering thermogenesis (NST) since a) it has as a primary physiological function the conversion of chemical energy to heat; and b) preliminary data from other tissues involved in NST (e.g., muscle) indicate that parallel mechanisms may be involved. Now that biochemical pathways have been proposed for brown fat thermogenesis, cellular models consistent with a thermodynamic representation can be formulated. Stated concisely, the thermogenic mechanism in a brown fat cell can be considered as an energy converter involving a sequence of cellular events controlled by signals over the autonomic nervous system. A thermodynamic description for NST is developed in terms of a nonisothermal system under steady-state conditions using network thermodynamics. Pathways simulated include mitochondrial ATP synthesis, a Na+/K+ membrane pump, and ionic diffusion through the adipocyte membrane.

  6. Human omentum fat-derived mesenchymal stem cells transdifferentiates into pancreatic islet-like cluster.

    PubMed

    Dhanasekaran, M; Indumathi, S; Harikrishnan, R; Mishra, Rashmi; Lissa, R P; Rajkumar, J S; Sudarsanam, D

    2013-10-01

    Current protocols of islet cell transplantation for the treatment of diabetes mellitus have been hampered by islet availability and allograft rejection. Although bone marrow and subcutaneous adipose tissue stem cells feature their tissue repair efficacy, applicability of stem cells from various sources is being researched to develop a promising therapy for diabetes mellitus. Although omentum fat has emerged as an innovative source of stem cells, the dearth of researches confirming its transdifferentiation potential limits its applicability as a regenerative tool in diabetic therapy. Thus, this work is a maiden attempt to explore the colossal potency of omentum fat-derived stem cells on its lucrative differentiation ability. The plasticity of omentum fat stem cells was substantiated by transdifferentiation into pancreatic islet-like clusters, which was confirmed by dithizone staining and immunocytochemistry for insulin. It was also confirmed by the expression of pancreatic endocrine markers nestin and pancreatic duodenal homeobox 1 (Pdx 1) using Fluorescence-activated cell sorting (FACS), neurogenic 3, islet-1 transcription factor, paired box gene 4, Pdx 1 and insulin using quantitative real-time polymerase chain reaction and through insulin secretion assay. This study revealed the in vitro differentiation potency of omentum fat stem cells into pancreatic islet-like clusters. However, further research pursuits exploring its in vivo endocrine efficacy would make omentum fat stem cells a superior source for β-cell replacement therapy.

  7. Morphoelasticity in the development of brown alga Ectocarpus siliculosus: from cell rounding to branching

    PubMed Central

    Jia, Fei; Billoud, Bernard; Charrier, Bénédicte

    2017-01-01

    A biomechanical model is proposed for the growth of the brown alga Ectocarpus siliculosus. Featuring ramified uniseriate filaments, this alga has two modes of growth: apical growth and intercalary growth with branching. Apical growth occurs upon the mitosis of a young cell at one extremity and leads to a new tip cell followed by a cylindrical cell, whereas branching mainly occurs when a cylindrical cell becomes rounded and swells, forming a spherical cell. Given the continuous interplay between cell growth and swelling, a poroelastic model combining osmotic pressure and volumetric growth is considered for the whole cell, cytoplasm and cell wall. The model recovers the morphogenetic transformations of mature cells: transformation of a cylindrical shape into spherical shape with a volumetric increase, and then lateral branching. Our simulations show that the poro-elastic model, including the Mooney–Rivlin approach for hyper-elastic materials, can correctly reproduce the observations. In particular, branching appears to be a plasticity effect due to the high level of tension created after the increase in volume of mature cells. PMID:28228537

  8. MicroRNA-133 Controls Brown Adipose Determination in Skeletal Muscle Satellite Cells by Targeting Prdm16

    PubMed Central

    Yin, Hang; Pasut, Alessandra; Soleimani, Vahab D.; Bentzinger, C. Florian; Antoun, Ghadi; Thorn, Stephanie; Seale, Patrick; Fernando, Pasan; van IJcken, Wilfred; Grosveld, Frank; Dekemp, Robert A.; Boushel, Robert; Harper, Mary-Ellen; Rudnicki, Michael A.

    2013-01-01

    SUMMARY Brown adipose tissue (BAT) is an energy-dispensing thermogenic tissue that plays an important role in balancing energy metabolism. Lineage-tracing experiments indicate that brown adipocytes are derived from myogenic progenitors during embryonic development. However, adult skeletal muscle stem cells (satellite cells) have long been considered uniformly determined toward the myogenic lineage. Here, we report that adult satellite cells give rise to brown adipocytes and that microRNA-133 regulates the choice between myogenic and brown adipose determination by targeting the 3′UTR of Prdm16. Antagonism of microRNA-133 during muscle regeneration increases uncoupled respiration, glucose uptake, and thermogenesis in local treated muscle and augments whole-body energy expenditure, improves glucose tolerance, and impedes the development of diet-induced obesity. Finally, we demonstrate that miR-133 levels are downregulated in mice exposed to cold, resulting in de novo generation of satellite cell-derived brown adipocytes. Therefore, microRNA-133 represents an important therapeutic target for the treatment of obesity. PMID:23395168

  9. Safety Concern between Autologous Fat Graft, Mesenchymal Stem Cell and Osteosarcoma Recurrence

    PubMed Central

    Perrot, Pierre; Rousseau, Julie; Bouffaut, Anne-Laure; Rédini, Françoise; Cassagnau, Elisabeth; Deschaseaux, Frédéric; Heymann, Marie-Françoise; Heymann, Dominique; Duteille, Franck; Trichet, Valérie; Gouin, François

    2010-01-01

    Background Osteosarcoma is the most common malignant primary bone tumour in young adult treated by neo adjuvant chemotherapy, surgical tumor removal and adjuvant multidrug chemotherapy. For correction of soft tissue defect consecutive to surgery and/or tumor treatment, autologous fat graft has been proposed in plastic and reconstructive surgery. Principal Findings We report here a case of a late local recurrence of osteosarcoma which occurred 13 years after the initial pathology and 18 months after a lipofilling procedure. Because such recurrence was highly unexpected, we investigated the possible relationship of tumor growth with fat injections and with mesenchymal stem/stromal cell like cells which are largely found in fatty tissue. Results obtained in osteosarcoma pre-clinical models show that fat grafts or progenitor cells promoted tumor growth. Significance These observations and results raise the question of whether autologous fat grafting is a safe reconstructive procedure in a known post neoplasic context. PMID:20544017

  10. Dedifferentiated fat cells: an alternative source of adult multipotent cells from the adipose tissues

    PubMed Central

    Shen, Jie-fei; Sugawara, Atsunori; Yamashita, Joe; Ogura, Hideo; Sato, Soh

    2011-01-01

    When adipose-derived stem cells (ASCs) are retrieved from the stromal vascular portion of adipose tissue, a large amount of mature adipocytes are often discarded. However, by modified ceiling culture technique based on their buoyancy, mature adipocytes can be easily isolated from the adipose cell suspension and dedifferentiated into lipid-free fibroblast-like cells, named dedifferentiated fat (DFAT) cells. DFAT cells re-establish active proliferation ability and undertake multipotent capacities. Compared with ASCs and other adult stem cells, DFAT cells showed unique advantages in their abundance, isolation and homogeneity. In this concise review, the establishment and culture methods of DFAT cells are introduced and the current profiles of their cellular nature are summarized. Under proper induction culture in vitro or environment in vivo, DFAT cells could demonstrate adipogenic, osteogenic, chondrogenic and myogenic potentials. In angiogenic conditions, DFAT cells could exhibit perivascular characteristics and elicit neovascularization. Our preliminary findings also suggested the pericyte phenotype underlying such cell lineage, which supported a novel interpretation about the common origin of mesenchymal stem cells and tissue-specific stem cells within blood vessel walls. Current research on DFAT cells indicated that this alternative source of adult multipotent cells has great potential in tissue engineering and regenerative medicine. PMID:21789960

  11. Dedifferentiated fat cells: an alternative source of adult multipotent cells from the adipose tissues.

    PubMed

    Shen, Jie-fei; Sugawara, Atsunori; Yamashita, Joe; Ogura, Hideo; Sato, Soh

    2011-07-01

    When adipose-derived stem cells (ASCs) are retrieved from the stromal vascular portion of adipose tissue, a large amount of mature adipocytes are often discarded. However, by modified ceiling culture technique based on their buoyancy, mature adipocytes can be easily isolated from the adipose cell suspension and dedifferentiated into lipid-free fibroblast-like cells, named dedifferentiated fat (DFAT) cells. DFAT cells re-establish active proliferation ability and undertake multipotent capacities. Compared with ASCs and other adult stem cells, DFAT cells showed unique advantages in their abundance, isolation and homogeneity. In this concise review, the establishment and culture methods of DFAT cells are introduced and the current profiles of their cellular nature are summarized. Under proper induction culture in vitro or environment in vivo, DFAT cells could demonstrate adipogenic, osteogenic, chondrogenic and myogenic potentials. In angiogenic conditions, DFAT cells could exhibit perivascular characteristics and elicit neovascularization. Our preliminary findings also suggested the pericyte phenotype underlying such cell lineage, which supported a novel interpretation about the common origin of mesenchymal stem cells and tissue-specific stem cells within blood vessel walls. Current research on DFAT cells indicated that this alternative source of adult multipotent cells has great potential in tissue engineering and regenerative medicine.

  12. FAT10 suppression stabilizes oxidized proteins in liver cells: Effects of HCV and ethanol.

    PubMed

    Ganesan, Murali; Hindman, Joseph; Tillman, Brittany; Jaramillo, Lee; Poluektova, Larisa I; French, Barbara A; Kharbanda, Kusum K; French, Samuel W; Osna, Natalia A

    2015-12-01

    FAT10 belongs to the ubiquitin-like modifier (ULM) family that targets proteins for degradation and is recognized by 26S proteasome. FAT10 is presented on immune cells and under the inflammatory conditions, is synergistically induced by IFNγ and TNFα in the non-immune (liver parenchymal) cells. It is not clear how viral proteins and alcohol regulate FAT10 expression on liver cells. In this study, we aimed to investigate whether FAT10 expression on liver cells is activated by the innate immunity factor, IFNα and how HCV protein expression in hepatocytes and ethanol-induced oxidative stress affect the level of FAT10 in liver cells. For this study, we used HCV(+) transgenic mice that express structural HCV proteins and their HCV(-) littermates. Mice were fed Lieber De Carli diet (control and ethanol) as specified in the NIH protocol for chronic-acute ethanol feeding. Alcohol exposure enhanced steatosis, induced oxidative stress and decreased proteasome activity in the liversof these mice, with more robust response to ethanol in HCV(+) mice. IFNα induced transcriptional activation of FAT10 in liver cells, which was dysregulated by ethanol feeding. Accordingly, IFNα-activated expression of FAT10 in hepatocytes (measured by indirect immunofluorescent of liver tissue) was also suppressed by ethanol exposure in both HCV(+) and HCV(-) mice. This suppression was accompanied with ethanol-mediated induction of lipid peroxidation marker, 4-HNE. All aforementioned effects of ethanol were attenuated by in vivo feeding of mice with the pro-methylating agent, betaine, which exhibits strong anti-oxidant properties. Based on this study, we hypothesize that FAT10 targets oxidatively modified proteins for proteasomal degradation, and that the reduction in FAT10 levels along with decreased proteasome activity may contribute to stabilization of these altered proteins in hepatocytes. In conclusion, IFNα induced FAT10 expression, which is suppressed by ethanol feeding in both HCV

  13. Berardinelli-Seip Congenital Lipodystrophy 2/Seipin Is Not Required for Brown Adipogenesis but Regulates Brown Adipose Tissue Development and Function

    PubMed Central

    Zhou, Hongyi; Black, Stephen M.; Benson, Tyler W.; Weintraub, Neal L.

    2016-01-01

    Brown adipose tissue (BAT) plays a unique role in regulating whole-body energy homeostasis by dissipating energy through thermogenic uncoupling. Berardinelli-Seip congenital lipodystrophy (BSCL) type 2 (BSCL2; also known as seipin) is a lipodystrophy-associated endoplasmic reticulum membrane protein essential for white adipocyte differentiation. Whether BSCL2 directly participates in brown adipocyte differentiation, development, and function, however, is unknown. We show that BSCL2 expression is increased during brown adipocyte differentiation. Its deletion does not impair the classic brown adipogenic program but rather induces premature activation of differentiating brown adipocytes through cyclic AMP (cAMP)/protein kinase A (PKA)-mediated lipolysis and fatty acid and glucose oxidation, as well as uncoupling. cAMP/PKA signaling is physiologically activated during neonatal BAT development in wild-type mice and greatly potentiated in mice with genetic deletion of Bscl2 in brown progenitor cells, leading to reduced BAT mass and lipid content during neonatal brown fat formation. However, prolonged overactivation of cAMP/PKA signaling during BAT development ultimately causes apoptosis of brown adipocytes through inflammation, resulting in BAT atrophy and increased overall adiposity in adult mice. These findings reveal a key cell-autonomous role for BSCL2 in controlling BAT mass/activity and provide novel insights into therapeutic strategies targeting cAMP/PKA signaling to regulate brown adipocyte function, viability, and metabolic homeostasis. PMID:27185876

  14. Fat grafting to the breast and adipose-derived stem cells: recent scientific consensus and controversy.

    PubMed

    Mizuno, Hiroshi; Hyakusoku, Hiko

    2010-01-01

    Recent technical advances in fat grafting and the development of surgical devices such as liposuction cannulae have made fat grafting a relatively safe and effective procedure. However, new guidelines issued by the American Society of Plastic Surgeons in 2009 announced that fat grafting to the breast is not a strongly recommended procedure, as there are limited scientific data on the safety and efficacy of this particular type of fat transfer. Recent progress by several groups has revealed that multipotent adult stem cells are present in human adipose tissue. This cell population, termed adipose-derived stem cells (ADSC), represents a promising approach to future cell-based therapies, such as tissue engineering and regeneration. In fact, several reports have shown that ADSC play a pivotal role in graft survival through both adipogenesis and angiogenesis. Although tissue augmentation by fat grafting does have several advantages in that it is a noninvasive procedure and results in minimal scarring, it is essential that such a procedure be supported by evidence-based medicine and that further basic scientific and clinical research is conducted to ensure that fat grafting is a safe and effective procedure.

  15. Chemical and enzymatic fractionation of cell walls from Fucales: insights into the structure of the extracellular matrix of brown algae

    PubMed Central

    Deniaud-Bouët, Estelle; Kervarec, Nelly; Michel, Gurvan; Tonon, Thierry; Kloareg, Bernard; Hervé, Cécile

    2014-01-01

    Background and Aims Brown algae are photosynthetic multicellular marine organisms evolutionarily distant from land plants, with a distinctive cell wall. They feature carbohydrates shared with plants (cellulose), animals (fucose-containing sulfated polysaccharides, FCSPs) or bacteria (alginates). How these components are organized into a three-dimensional extracellular matrix (ECM) still remains unclear. Recent molecular analysis of the corresponding biosynthetic routes points toward a complex evolutionary history that shaped the ECM structure in brown algae. Methods Exhaustive sequential extractions and composition analyses of cell wall material from various brown algae of the order Fucales were performed. Dedicated enzymatic degradations were used to release and identify cell wall partners. This approach was complemented by systematic chromatographic analysis to study polymer interlinks further. An additional structural assessment of the sulfated fucan extracted from Himanthalia elongata was made. Key Results The data indicate that FCSPs are tightly associated with proteins and cellulose within the walls. Alginates are associated with most phenolic compounds. The sulfated fucans from H. elongata were shown to have a regular α-(1→3) backbone structure, while an alternating α-(1→3), (1→4) structure has been described in some brown algae from the order Fucales. Conclusions The data provide a global snapshot of the cell wall architecture in brown algae, and contribute to the understanding of the structure–function relationships of the main cell wall components. Enzymatic cross-linking of alginates by phenols may regulate the strengthening of the wall, and sulfated polysaccharides may play a key role in the adaptation to osmotic stress. The emergence and evolution of ECM components is further discussed in relation to the evolution of multicellularity in brown algae. PMID:24875633

  16. Subcutaneous Adipose Cell Size and Distribution: Relationship to Insulin Resistance and Body Fat

    PubMed Central

    McLaughlin, T; Lamendola, C; Coghlan, N; Liu, TC; Lerner, K; Sherman, A; Cushman, SW

    2015-01-01

    Metabolic heterogeneity among obese individuals may be attributable to differences in adipose cell size. We sought to clarify this by quantifying adipose cell-size distribution, body fat, and insulin-mediated glucose uptake in overweight/moderately-obese individuals. 148 healthy nondiabetic subjects with BMI 25–38 kg/m2 underwent subcutaneous adipose tissue biopsies and quantification of insulin-mediated glucose uptake with steady-state plasma glucose concentrations (SSPG) during the modified insulin suppression test. Cell-size distributions were obtained with Beckman Coulter Multisizer. Primary endpoints included % small adipose cells and diameter of large adipose cells. Cell-size and metabolic parameters were compared by regression for the whole group; according to IR and IS subgroups; and by body fat quintile. Both large and small adipose cells were present in nearly equal proportions. Percent small cells was associated with SSPG (r=0.26, p=0.003). Compared to BMI-matched IS individuals, IR counterparts demonstrated fewer, but larger large adipose cells, and a greater proportion of small-to-large adipose cells. Diameter of the large adipose cells was associated with %body fat (r=0.26, p=0.014), female sex (r=0.21, p=0.036), and SSPG (r=0.20, p=0.012). In the highest vs lowest % body fat quintile, adipose cell size increased by only 7% whereas adipose cell number increased by 74%. Recruitment of adipose cells is required for expansion of body fat mass beyond BMI of 25 kg/m2. Insulin resistance is associated with accumulation of small adipose cells and enlargement of large adipose cells. These data support the notion that impaired adipogenesis may underlie insulin resistance. PMID:23666871

  17. Ultrasound-induced stress responses of Panax ginseng cells: enzymatic browning and phenolics production.

    PubMed

    Wu, Jianyong; Lin, Lidong

    2002-01-01

    The stress metabolic activities of Panax ginseng (P. ginseng) cells induced by low-energy ultrasound (US) were examined. P. ginseng cells in suspension cultures were exposed to 38.5 kHz US at two power levels (power density 13.7 and 61 mW/cm(3)) for 2 min. The US treatment caused rapid increase in the intracellular levels of polyphenol oxidase (PPO), peroxidase (PO), and phenylalanine ammonia lyase (PAL) and the production of polyphenols (PP) and phenolic compounds. The US-induced enzyme activities and phenolics production are part of plant stress responses to a mechanical stimulus. The much higher PPO activity and rate of PP production in the sonicated cultures are correlated to enzymatic browning, suggestive of physical damage and membrane permeabilization of the cells by US. The cells after sonication also showed decreased water content and cell volume, which may also be attributed to US-induced cell membrane permeabilization and water release. High-pressure shock and fluid shear stress arising from acoustic cavitation were regarded as the major causes of the responses. Nevertheless, the US exposure caused only temporary cell growth depression but no net loss of biomass yield of the culture.

  18. Fighting Fat with Fat: The Expanding Field of Adipose Stem Cells

    PubMed Central

    Zeve, Daniel; Tang, Wei; Graff, Jon

    2010-01-01

    We are in the midst of a dire, unprecedented, and global epidemic of obesity and secondary sequelae, most prominently diabetes and hyperlipidemia. Underlying this epidemic is the most hated of cells, adipocytes, and their inherent dynamic ability to expand and renew. This capacity highlights a heretofore undefined stem compartment. Recent in vivo studies, relying upon lineage tracing and flow cytometry methods, have begun to unravel the identity of adipose stem cells, their niche, and the dynamism central to adipose expansion. Thus, the field is moving in a direction that may allow us to manipulate adipose stem cells to beneficial therapeutic ends. PMID:19896439

  19. Phenotypic and functional properties of feline dedifferentiated fat cells and adipose-derived stem cells.

    PubMed

    Kono, Shota; Kazama, Tomohiko; Kano, Koichiro; Harada, Kayoko; Uechi, Masami; Matsumoto, Taro

    2014-01-01

    It has been reported that mature adipocyte-derived dedifferentiated fat (DFAT) cells show multilineage differentiation potential similar to that observed in mesenchymal stem cells. Since DFAT cells can be prepared from a small quantity of adipose tissue, they could facilitate cell-based therapies in small companion animals such as cats. The present study examined whether multipotent DFAT cells can be generated from feline adipose tissue, and the properties of DFAT cells were compared with those of adipose-derived stem cells (ASCs). DFAT cells and ASCs were prepared from the floating mature adipocyte fraction and the stromal vascular fraction, respectively, of collagenase-digested feline omental adipose tissue. Both cell types were evaluated for growth kinetics, colony-forming unit fibroblast (CFU-F) frequency, immunophenotypic properties, and multilineage differentiation potential. DFAT cells and ASCs could be generated from approximately 1g of adipose tissue and were grown and subcultured on laminin-coated dishes. The frequency of CFU-Fs in DFAT cells (35.8%) was significantly higher than that in ASCs (20.8%) at passage 1 (P1). DFAT cells and ASCs displayed similar immunophenotypes (CD44(+), CD90(+), CD105(+), CD14(-), CD34(-) and CD45(-)). Alpha-smooth muscle actin-positive cells were readily detected in ASCs (15.2±7.2%) but were rare in DFAT cells (2.2±3.2%) at P1. Both cell types exhibited adipogenic, osteogenic, chondrogenic, and smooth muscle cell differentiation potential in vitro. In conclusion, feline DFAT cells exhibited similar properties to ASCs but displayed higher CFU-F frequency and greater homogeneity. DFAT cells, like ASCs, may be an attractive source for cell-based therapies in cats.

  20. Gravity separation of fat, somatic cells, and bacteria in raw and pasteurized milks.

    PubMed

    Caplan, Z; Melilli, C; Barbano, D M

    2013-04-01

    The objective of experiment 1 was to determine if the extent of gravity separation of milk fat, bacteria, and somatic cells is influenced by the time and temperature of gravity separation or the level of contaminating bacteria present in the raw milk. The objective of experiment 2 was to determine if different temperatures of milk heat treatment affected the gravity separation of milk fat, bacteria, and somatic cells. In raw milk, fat, bacteria, and somatic cells rose to the top of columns during gravity separation. About 50 to 80% of the fat and bacteria were present in the top 8% of the milk after gravity separation of raw milk. Gravity separation for 7h at 12°C or for 22h at 4°C produced equivalent separation of fat, bacteria, and somatic cells. The completeness of gravity separation of fat was influenced by the level of bacteria in the milk before separation. Milk with a high bacterial count had less (about 50 to 55%) gravity separation of fat than milk with low bacteria count (about 80%) in 22h at 4°C. Gravity separation caused fat, bacteria, and somatic cells to rise to the top of columns for raw whole milk and high temperature, short-time pasteurized (72.6°C, 25s) whole milk. Pasteurization at ≥76.9°C for 25s prevented all 3 components from rising, possibly due to denaturation of native bovine immunoglobulins that normally associate with fat, bacteria, and somatic cells during gravity separation. Gravity separation can be used to produce reduced-fat milk with decreased bacterial and somatic cell counts, and may be a critical factor in the history of safe and unique traditional Italian hard cheeses produced from gravity-separated raw milk. A better understanding of the mechanism of this natural process could lead to the development of new nonthermal thermal technology (that does not involve heating the milk to high temperatures) to remove bacteria and spores from milk or other liquids.

  1. Dissecting the brown adipogenic regulatory network using integrative genomics

    PubMed Central

    Pradhan, Rachana N.; Bues, Johannes J.; Gardeux, Vincent; Schwalie, Petra C.; Alpern, Daniel; Chen, Wanze; Russeil, Julie; Raghav, Sunil K.; Deplancke, Bart

    2017-01-01

    Brown adipocytes regulate energy expenditure via mitochondrial uncoupling, which makes them attractive therapeutic targets to tackle obesity. However, the regulatory mechanisms underlying brown adipogenesis are still poorly understood. To address this, we profiled the transcriptome and chromatin state during mouse brown fat cell differentiation, revealing extensive gene expression changes and chromatin remodeling, especially during the first day post-differentiation. To identify putatively causal regulators, we performed transcription factor binding site overrepresentation analyses in active chromatin regions and prioritized factors based on their expression correlation with the bona-fide brown adipogenic marker Ucp1 across multiple mouse and human datasets. Using loss-of-function assays, we evaluated both the phenotypic effect as well as the transcriptomic impact of several putative regulators on the differentiation process, uncovering ZFP467, HOXA4 and Nuclear Factor I A (NFIA) as novel transcriptional regulators. Of these, NFIA emerged as the regulator yielding the strongest molecular and cellular phenotypes. To examine its regulatory function, we profiled the genomic localization of NFIA, identifying it as a key early regulator of terminal brown fat cell differentiation. PMID:28181539

  2. [Studies on cerebral scavenger cells (fluorescent granular perithelial cells) - especially uptake and digestion of incorporated fat].

    PubMed

    Mato, M; Ookawara, S; Sano, M; Kurihara, K

    1982-10-01

    Small cerebral vessels including capillaries are provided with the specific barrier (blood brain barrier) for a transport of substances from blood to cerebral tissue. However, it is also established that fat soluble substances are easily permeable in this barrier. Along cerebral small vessels, the cells having intracellular fluorescent granules are distributed and named "fluorescent granular perithelia (F.G.P.)" by the authors. They are potent in the uptake capacity for exogenous substances as reported in the previous papers. In this study, 24 male Wistar rats aged 8 months and 2.5 years old were employed. They were fed with a fat rich chow (Oriental Co.) containing 10% lard, 2% cholesterol and methylthiouracil for one day and fifteen days. Half of them was subcutaneously injected with 5 mg/kg of elastase (Eisai Co.) dissolved in physiological saline once a day. To clarify the effect of elastase on fat incorporated by F.G.P., 4 rats aged 2.5 years were fed with a fat rich chow for 2 days. After then, they were fed with ordinal rat chow for 3 days with or without elastase injection. After decapitation, cerebral cortex of rats was removed in cold physiological saline and sliced with a blade. Half of the sliced specimens was prepared by the authors' method (Mato and Ookawara, 1979) and stained with hematoxylin eosin, periodic acid Schiff reaction and sudan black B for a light microscopical observation. The other half of the specimens was immersed in a mixture containing 2% paraformaldehyde and 2.5% glutaraldehyde buffered with 0.1M phosphate solution (pH 7.4) for 10 h. The specimens were then postfixed with osmium tetroxide buffered with the same solution for 2h. The other procedures for embedding and cutting were the same as in a routine method. Following findings were obtained at the light and electron microscopical levels; when they were fed with a fat rich chow, fat in blood passed through vascular walls and was taken up by F.G.P.. The quantity of fatty deposits

  3. Rictor/mTORC2Loss in the Myf5-lineage Reprograms Brown Fat Metabolism and Protects Mice against Obesity and Metabolic Disease

    PubMed Central

    Hung, Chien-Min; Calejman, Camila Martinez; Sanchez-Gurmaches, Joan; Li, Huawei; Clish, Clary B.; Hettmer, Simone; Wagers, Amy J.; Guertin, David A.

    2014-01-01

    Summary The in vivo functions of mTORC2, and the signaling mechanisms that control brown adipose tissue (BAT) fuel utilization and activity, are not well understood. Here, by conditionally deleting Rictorin the Myf5-lineage, we provide in vivo evidence that mTORC2 is dispensable for skeletal muscle development and regeneration but essential for BAT growth. Furthermore, deleting RictorinMyf5 precursors shifts BAT metabolism to a more oxidative and less lipogenic state and protects mice from obesity and metabolic disease at thermoneutrality. We additionally find that Rictor is required for brown adipocyte differentiation in vitro, that the mechanismspecifically requires AKT1 hydrophobic motif phosphorylation but is independent of pan-AKT signaling, and is rescued with BMP7. Our findings provide new insights into the signaling circuitry that regulates brown adipocytes and could have important implications for developing therapies aimed at increasing energy expenditure as a means to combat human obesity. PMID:25001283

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

    Technology Transfer Automated Retrieval System (TEKTRAN)

    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 ...

  5. High fat feeding affects the number of GPR120 cells and enteroendocrine cells in the mouse stomach

    PubMed Central

    Widmayer, Patricia; Goldschmid, Hannah; Henkel, Helena; Küper, Markus; Königsrainer, Alfred; Breer, Heinz

    2015-01-01

    Long-term intake of dietary fat is supposed to be associated with adaptive reactions of the organism and it is assumptive that this is particularly true for fat responsive epithelial cells in the mucosa of the gastrointestinal tract. Recent studies suggest that epithelial cells expressing the receptor for medium and long chain fatty acids, GPR120 (FFAR4), may operate as fat sensors. Changes in expression level and/or cell density are supposed to be accompanied with a consumption of high fat (HF) diet. To assess whether feeding a HF diet might impact on the expression of fatty acid receptors or the number of lipid sensing cells as well as enteroendocrine cell populations, gastric tissue samples of non-obese and obese mice were compared using a real time PCR and immunohistochemical approach. In this study, we have identified GPR120 cells in the corpus region of the mouse stomach which appeared to be brush cells. Monitoring the effect of HF diet on the expression of GPR120 revealed that after 3 weeks and 6 months the level of mRNA for GPR120 in the tissue was significantly increased which coincided with and probably reflected a significant increase in the number of GPR120 positive cells in the corpus region; in contrast, within the antrum region, the number of GPR120 cells decreased. Furthermore, dietary fat intake also led to changes in the number of enteroendocrine cells producing either ghrelin or gastrin. After 3 weeks and even more pronounced after 6 months the number of ghrelin cells and gastrin cells was significantly increased. These results imply that a HF diet leads to significant changes in the cellular repertoire of the stomach mucosa. Whether these changes are a consequence of the direct exposure to HF in the luminal content or a physiological response to the high level of fat in the body remains elusive. PMID:25774135

  6. Laser capture microdissection in Ectocarpus siliculosus: the pathway to cell-specific transcriptomics in brown algae.

    PubMed

    Saint-Marcoux, Denis; Billoud, Bernard; Langdale, Jane A; Charrier, Bénédicte

    2015-01-01

    Laser capture microdissection (LCM) facilitates the isolation of individual cells from tissue sections, and when combined with RNA amplification techniques, it is an extremely powerful tool for examining genome-wide expression profiles in specific cell-types. LCM has been widely used to address various biological questions in both animal and plant systems, however, no attempt has been made so far to transfer LCM technology to macroalgae. Macroalgae are a collection of widespread eukaryotes living in fresh and marine water. In line with the collective effort to promote molecular investigations of macroalgal biology, here we demonstrate the feasibility of using LCM and cell-specific transcriptomics to study development of the brown alga Ectocarpus siliculosus. We describe a workflow comprising cultivation and fixation of algae on glass slides, laser microdissection, and RNA amplification. To illustrate the effectiveness of the procedure, we show qPCR data and metrics obtained from cell-specific transcriptomes generated from both upright and prostrate filaments of Ectocarpus.

  7. Brown adipose tissue and thermogenesis.

    PubMed

    Fenzl, Anna; Kiefer, Florian W

    2014-07-01

    The growing understanding of adipose tissue as an important endocrine organ with multiple metabolic functions has directed the attention to the (patho)physiology of distinct fat depots. Brown adipose tissue (BAT), in contrast to bona fide white fat, can dissipate significant amounts of chemical energy through uncoupled respiration and heat production (thermogenesis). This process is mediated by the major thermogenic factor uncoupling protein-1 and can be activated by certain stimuli, such as cold exposure, adrenergic compounds or genetic alterations. White adipose tissue (WAT) depots, however, also possess the capacity to acquire brown fat characteristics in response to thermogenic stimuli. The induction of a BAT-like cellular and molecular program in WAT has recently been termed "browning" or "beiging". Promotion of BAT activity or the browning of WAT is associated with in vivo cold tolerance, increased energy expenditure, and protection against obesity and type 2 diabetes. These preclinical observations have gained additional significance with the recent discovery that active BAT is present in adult humans and can be detected by 18fluor-deoxy-glucose positron emission tomography coupled with computed tomography. As in rodents, human BAT can be activated by cold exposure and is associated with increased energy turnover and lower body fat mass. Despite the tremendous progress in brown fat research in recent years, pharmacological concepts to harness BAT function therapeutically are currently still lacking.

  8. EFFECTS OF PUROMYCIN ON THE STRUCTURE OF RAT INTESTINAL EPITHELIAL CELLS DURING FAT ABSORPTION

    PubMed Central

    Friedman, Harold I.; Cardell, Robert R.

    1972-01-01

    This report provides information on the morphology of rat intestinal epithelial cells during fat absorption. In addition, the role of protein metabolism in this process has been evaluated by blocking its synthesis with puromycin and studying the fine structure of mucosal cells from rats at various times after fat intubation. The results indicate that SER-derived vesicles, containing fat droplets, migrate from the apical cytoplasm of the absorptive cell and fuse with saccules or vacuoles of the Golgi complex. Arguments are made that the Golgi complex is important in completing chylomicron formation and in providing appropriate enveloping membranes for the chylomicron. Such membranes may be necessary for Golgi vacuoles to fuse with the lateral cell membranes and release chylomicra. Puromycin treatment causes the absorptive cell to accumulate increased quantities of lipid that are devoid of membrane during fat absorption. In addition, puromycin-treated cells contain much less RER and Golgi membranes are strikingly decreased in number. In this paper we discuss the consequences of these abnormalities and suggest that continued protein synthesis by the RER is required in order to generate Golgi membranes. If such membranes are absent the cell's ability to discarge chylomicra is impaired and lipid accumulates. PMID:4331298

  9. Sedentary lifestyle related exosomal release of Hotair from gluteal-femoral fat promotes intestinal cell proliferation

    PubMed Central

    Lu, Xiaozhao; Bai, Danna; Liu, Xiangwei; Zhou, Chen; Yang, Guodong

    2017-01-01

    Pioneering epidemiological work has established strong association of sedentary lifestyle and obesity with the risk of colorectal cancer, while the detailed underlying mechanism remains unknown. Here we show that Hotair (HOX transcript antisense RNA) is a pro-adipogenic long non-coding RNA highly expressed in gluteal-femoral fat over other fat depots. Hotair knockout in adipose tissue results in gluteal-femoral fat defect. Squeeze of the gluteal-femoral fat induces intestinal proliferation in wildtype mice, while not in Hotair knockout mice. Mechanistically, squeeze of the gluteal-femoral fat induces exosomal Hotair secretion mainly by transcriptional upregulation of Hotair via NFκB. And increased exosomal Hotair in turn circulates in the blood and is partially endocytosed by the intestine, finally promoting the stemness and proliferation of intestinal stem/progenitor cells via Wnt activation. Clinically, obese subjects with sedentary lifestyle have much higher exosomal HOTAIR expression in the serum. These findings establish that sedentary lifestyle promotes exosomal Hotair release from the gluteal-femoral fat, which in turn facilitates intestinal stem and/or progenitor proliferation, raising a possible link between sedentary lifestyle with colorectal tumorigenesis. PMID:28361920

  10. Nicotine withdrawal increases body weight, neuropeptide Y and Agouti-related protein expression in the hypothalamus and decreases uncoupling protein-3 expression in the brown adipose tissue in high-fat fed mice.

    PubMed

    Fornari, Alice; Pedrazzi, Patrizia; Lippi, Giordano; Picciotto, Marina R; Zoli, Michele; Zini, Isabella

    2007-01-03

    Nicotine is known to decrease body weight in normal rodents and human smokers, whereas nicotine withdrawal or smoking cessation can increase body weight. We have found that mice fed a high fat diet do not show the anorectic effect of chronic nicotine treatment, but do increase their body weight following nicotine withdrawal. Nicotine withdrawal is accompanied by increased expression of the orexigenic peptides neuropeptide Y and Agouti-related protein in the hypothalamus, and decreased expression of the metabolic protein uncoupling protein-3 in brown adipose tissue. These data suggest that diet can influence the ability of nicotine to modulate body weight regulation and demonstrate that chronic nicotine exposure results in adaptive changes in central and peripheral molecules which regulate feeding behavior and energy metabolism.

  11. Brown Syndrome

    MedlinePlus

    ... Does Brown syndrome cause eye problems besides abnormal eye movements? In the more severely affected cases of Brown ... acquired and congenital cases. In congenital cases, the eye movement problem is usually constant and unlikely to resolve ...

  12. Rictor/mTORC2 loss in the Myf5 lineage reprograms brown fat metabolism and protects mice against obesity and metabolic disease.

    PubMed

    Hung, Chien-Min; Calejman, Camila Martinez; Sanchez-Gurmaches, Joan; Li, Huawei; Clish, Clary B; Hettmer, Simone; Wagers, Amy J; Guertin, David A

    2014-07-10

    The in vivo functions of mechanistic target of rapamycin complex 2 (mTORC2) and the signaling mechanisms that control brown adipose tissue (BAT) fuel utilization and activity are not well understood. Here, by conditionally deleting Rictor in the Myf5 lineage, we provide in vivo evidence that mTORC2 is dispensable for skeletal muscle development and regeneration but essential for BAT growth. Furthermore, deleting Rictor in Myf5 precursors shifts BAT metabolism to a more oxidative and less lipogenic state and protects mice from obesity and metabolic disease at thermoneutrality. We additionally find that Rictor is required for brown adipocyte differentiation in vitro and that the mechanism specifically requires AKT1 hydrophobic motif phosphorylation but is independent of pan-AKT signaling and is rescued with BMP7. Our findings provide insights into the signaling circuitry that regulates brown adipocytes and could have important implications for developing therapies aimed at increasing energy expenditure as a means to combat human obesity.

  13. The Ontogeny of Brown Adipose Tissue.

    PubMed

    Symonds, Michael E; Pope, Mark; Budge, Helen

    2015-01-01

    There are three different types of adipose tissue (AT)-brown, white, and beige-that differ with stage of development, species, and anatomical location. Of these, brown AT (BAT) is the least abundant but has the greatest potential impact on energy balance. BAT is capable of rapidly producing large amounts of heat through activation of the unique uncoupling protein 1 (UCP1) located within the inner mitochondrial membrane. White AT is an endocrine organ and site of lipid storage, whereas beige AT is primarily white but contains some cells that possess UCP1. BAT first appears in the fetus around mid-gestation and is then gradually lost through childhood, adolescence, and adulthood. We focus on the interrelationships between adipocyte classification, anatomical location, and impact of diet in early life together with the extent to which fat development differs between the major species examined. Ultimately, novel dietary interventions designed to reactivate BAT could be possible.

  14. Repeated allergen exposure of sensitized Brown-Norway rats induces airway cell DNA synthesis and remodelling.

    PubMed

    Salmon, M; Walsh, D A; Koto, H; Barnes, P J; Chung, K F

    1999-09-01

    Chronic inflammation in asthmatic airways can lead to characteristic airway smooth muscle (ASM) thickening and pathological changes within the airway wall. This study assessed the effect of repeated allergen exposure on ASM and epithelial cell deoxyribonucleic acid (DNA) synthesis, cell recruitment and airway wall pathology. Brown-Norway rats were sensitized and then exposed to ovalbumin or saline aerosol every 3 days on six occasions. After the final exposure, rats were administered twice daily for 7 days with the DNA S-phase marker bromodeoxyuridine (BrdU). Using a triple immunohistochemical staining technique, BrdU incorporation into ASM and epithelium was quantified employing computer-assisted image analysis. There were >3-fold mean increases in BrdU incorporation into ASM from 1.3% of cells (95% confidence interval (CI) 1.0-1.6) in saline controls to 4.7% (95% CI 2.6-6.7) after allergen exposure (p<0.001), and in airway epithelium, from 1.3 (95% CI 0.6-2.0) BrdU-positive cells x mm basement membrane(-1) in saline controls to 4.9 (95% CI 3.0-6.7) after allergen exposure (p<0.001). There was increased subepithelial collagen deposition and mucus secretion along with a significant eosinophil and lymphocyte recruitment to the airways. Increased rates of deoxyribonucleic acid synthesis in both airway smooth muscle and epithelial cells along with changes to the airway wall pathology may precede the establishment of smooth muscle thickening and airway remodelling after repeated allergen exposure in rats. This model seems to be appropriate for studying structural changes within the airways as observed in asthma.

  15. Green synthesis of gold nanoparticles using brown algae Cystoseira baccata: Its activity in colon cancer cells.

    PubMed

    González-Ballesteros, N; Prado-López, S; Rodríguez-González, J B; Lastra, M; Rodríguez-Argüelles, M C

    2017-05-01

    This study is the first dealt with the use of brown macroalgae Cystoseira baccata (CB) extracts in obtaining gold nanoparticles (Au@CB) through an eco-friendly, fast, one-pot synthetic route. The formation of spherical, stable, polycrystalline nanoparticles with mean diameter of 8.4±2.2nm was demonstrated by UV-vis spectroscopy, TEM, HRTEM, STEM and zeta potential measurements. The extract appears to act as a protective agent where the particles are embedded, keeping them separated, avoiding aggregation and coalescence. The EELS and EDS analyses confirmed the elemental composition of the extract and nanoparticles. Moreover, the functional group of biomolecules present in CB and Au@CB were characterized by FTIR. The effects of CB extract and Au@CB were tested in vitro on the colon cancer cell lines HT-29 and Caco-2, as well as on normal primary neonatal dermal fibroblast cell line PCS-201-010. Results show a stronger cytotoxic effect against HT-29 than that on Caco-2; interestingly, a lack of toxicity on PCS-201-010 was obtained. Finally, the apoptotic activity was determined; Au@CB is able to induce apoptosis activation by the extrinsic and mitochondrial pathway in our CRC in vitro model. These encouraging results suggest that Au@CB has a significant potential for the treatment of colon rectal cancer.

  16. Selective Augmentation of Stem Cell Populations in Structural Fat Grafts for Maxillofacial Surgery

    PubMed Central

    Gardin, Chiara; Tieghi, Riccardo; Galiè, Manlio; Elia, Giovanni; Piattelli, Adriano; Pinton, Paolo; Bressan, Eriberto; Zavan, Barbara

    2014-01-01

    Structural fat grafting utilizes the centrifugation of liposuction aspirates to create a graded density of adipose tissue. This study was performed to qualitatively investigate the effects of centrifugation on stem cells present in adipose tissue. Liposuction aspirates were obtained from healthy donors and either not centrifuged or centrifuged at 1,800 rpm for 3 minutes. The obtained fat volumes were divided into three layers and then analyzed. The results demonstrate that centrifugation induces a different distribution of stem cells in the three layers. The high-density layer displays the highest expression of mesenchymal stem cell and endothelial markers. The low-density layer exhibits an enrichment of multipotent stem cells. We conclude that appropriate centrifugation concentrates stem cells. This finding may influence the clinical practice of liposuction aspirate centrifugation and enhance graft uptake. PMID:25375632

  17. High-fat diet is associated with obesity-mediated insulin resistance and β-cell dysfunction in Mexican Americans.

    PubMed

    Black, Mary Helen; Watanabe, Richard M; Trigo, Enrique; Takayanagi, Miwa; Lawrence, Jean M; Buchanan, Thomas A; Xiang, Anny H

    2013-04-01

    Consumption of energy-dense, nutrient-poor foods has contributed to the rising incidence of obesity and may underlie insulin resistance and β-cell dysfunction. Macronutrient intake patterns were examined in relation to anthropometric and metabolic traits in participants of BetaGene, a family-based study of obesity, insulin resistance, and β-cell dysfunction in Mexican Americans. Dietary intake, body composition, insulin sensitivity (SI), and β-cell function [Disposition Index (DI)] were assessed by food-frequency questionnaires, dual-energy X-ray absorptiometry, and intravenous glucose-tolerance tests, respectively. Patterns of macronutrient intake were identified by using a K-means model based on the proportion of total energy intake per day attributable to carbohydrate, fat, and protein and were tested for association with anthropometric and metabolic traits. Among 1150 subjects aged 18-65 y (73% female), tertiles of fat intake were associated with greater adiposity and lower SI, after adjustment for age, sex, and daily energy intake. Moreover, 3 distinct dietary patterns were identified: "high fat" (35% fat, 44% carbohydrate, 21% protein; n = 238), "moderate fat" (28% fat, 54% carbohydrate, 18% protein; n = 520), and "low fat" (20% fat, 65% carbohydrate, 15% protein; n = 392). Compared with the low-fat group, the high-fat group had higher age- and sex-adjusted mean body mass index, body fat percentage, and trunk fat and lower SI and DI. Further adjustment for daily energy intake by matching individuals across dietary pattern groups yielded similar results. None of the observed associations were altered after adjustment for physical activity; however, associations with SI and DI were attenuated after adjustment for adiposity. These findings suggest that high-fat diets may contribute to increased adiposity and concomitant insulin resistance and β-cell dysfunction in Mexican Americans.

  18. Signaling pathway puts the break on fat cell formation.

    PubMed

    MacDougald, O A

    2001-05-01

    Obesity is approaching epidemic proportions in the western industrialized world, and is also becoming a major problem among young people in eastern and developing countries. Unfortunately, excess fat or adipose tissue is associated with a wide array of health problems, including increased incidence of type II diabetes, cardiovascular disease, hypertension, sleep apnea, and skeletomuscular problems. Obesity is the second leading cause of death from "unnecessary" causes in the U.S. (after smoking), and costs individuals and society billions of dollars worldwide to treat. Despite common wisdom that "one just needs to eat less and exercise more" and a multi-billion-dollar diet industry, epidemiological data indicate that the incidence of obesity will continue to rise. This alarming trend is, in part, due to the unprecedented availability of energy-dense foods and an increasingly sedentary lifestyle. These environmental factors may be complicated in some individuals by an unfavorable genetic predisposition. Pharmaceutical companies lead active research programs to identify drugs that target weight control centers in the body and which may help individuals control their weight; however, no satisfactory magic bullet to fight obesity has yet come through the pipeline.

  19. Antiproliferative activity of brown Cuban propolis extract on human breast cancer cells.

    PubMed

    Popolo, Ada; Piccinelli, Lisa Anna; Morello, Silvana; Cuesta-Rubio, Osmany; Sorrentino, Rosalinda; Rastrelli, Luca; Pinto, Aldo

    2009-12-01

    Brown Cuban propolis (BCP) is the major type of propolis in Cuba; its chemical composition is exclusive and the principal component is nemorosone. In this study we investigated the antiproliferative activity of the ethanol extract of BCP on human breast cancer cell lines. The MTT assay showed a significant antiproliferative activity (P<0.005) of BCP on MCF-7 (estrogen receptor positive ER+) rather than MDA-MB 23 1 (ER-). This effect was concentration- (1-25 microg/mL) and time- (24-48 h) dependent, but it is only partially attributable to apoptosis. Indeed, our data showed that BCP administration to MCF-7 caused a significant (P>0.01) inhibition of cell growth in the G1 phase of cell cycle, which was mechanism dose- and time-dependent. 17-beta Estradiol (10 nM) administration to MCF-7 caused a significant (P<0.001), but not total reduction of BCP antiproliferative activity at concentrations of 1, 5 and 10 microg/mL, but not at the highest concentration (25 microg/mL). The coadministration of ICI 182,780 (100 nM), an antagonist of ER, on MCF-7 totally reduced the effect of BCP at 24 h, and showed a significant (P<0.001) reduction of BCP antiproliferative activity at 48 h. Thus it was hypothesized that BCP possesses an estrogen-like activity. It is to be noted, however, that BCP application to MDA-MB 23 1 at 48 h also induced increased cell mortality. Thus, it cannot be ruled out that BCP could not only interact with the ER, but also have an ER-independent activity.

  20. Pancreatic Fat Accumulation, Fibrosis, and Acinar Cell Injury in the Zucker Diabetic Fatty Rat Fed a Chronic High-Fat Diet

    PubMed Central

    Matsuda, Akiko; Makino, Naohiko; Tozawa, Tomohiro; Shirahata, Nakao; Honda, Teiichiro; Ikeda, Yushi; Sato, Hideyuki; Ito, Miho; Kakizaki, Yasuharu; Akamatsu, Manabu; Ueno, Yoshiyuki; Kawata, Sumio

    2014-01-01

    Objective The histological alteration of the exocrine pancreas in obesity has not been clarified. In the present study, we investigated biochemical and histological changes in the exocrine pancreas of obese model rats. Methods Zucker lean rats were fed a standard diet, and Zucker diabetic fatty (ZDF) rats were divided into 2 groups fed a standard diet and a high-fat diet, respectively. These experimental groups were fed each of the diets from 6 weeks until 12, 18, 24 weeks of age. We performed blood biochemical assays and histological analysis of the pancreas. Results In the ZDF rats fed a high-fat diet, the ratio of accumulated pancreatic fat area relative to exocrine gland area was increased significantly at 18 weeks of age in comparison with the other 2 groups (P < 0.05), and lipid droplets were observed in acinar cells. Subsequently, at 24 weeks of age in this group, pancreatic fibrosis and the serum exocrine pancreatic enzyme levels were increased significantly relative to the other 2 groups (P < 0.01). Conclusions In ZDF rats fed a chronic high-fat diet, fat accumulates in pancreatic acinar cells, and this fatty change seems to be related to subsequent pancreatic fibrosis and acinar cell injury. PMID:24717823

  1. Perinatal exposure to germinated brown rice and its gamma amino-butyric acid-rich extract prevents high fat diet-induced insulin resistance in first generation rat offspring

    PubMed Central

    Adamu, Hadiza Altine; Imam, Mustapha Umar; Ooi, Der-Jiun; Esa, Norhaizan Mohd; Rosli, Rozita; Ismail, Maznah

    2016-01-01

    Background Evidence suggests perinatal environments influence the risk of developing insulin resistance. Objective The present study was aimed at determining the effects of intrauterine exposure to germinated brown rice (GBR) and GBR-derived gamma (γ) aminobutyric acid (GABA) extract on epigenetically mediated high fat diet–induced insulin resistance. Design Pregnant Sprague Dawley rats were fed high-fat diet (HFD), HFD+GBR, or HFD+GABA throughout pregnancy until 4 weeks postdelivery. The pups were weighed weekly and maintained on normal pellet until 8 weeks postdelivery. After sacrifice, biochemical markers of obesity and insulin resistance including oral glucose tolerance test, adiponectin, leptin, and retinol binding protein-4 (RBP4) were measured. Hepatic gene expression changes and the global methylation and histone acetylation levels were also evaluated. Results Detailed analyses revealed that mothers given GBR and GABA extract, and their offspring had increased adiponectin levels and reduced insulin, homeostasis model assessment of insulin resistance, leptin, oxidative stress, and RBP4 levels, while their hepatic mRNA levels of GLUT2 and IPF1 were increased. Furthermore, GBR and GABA extract lowered global DNA methylation levels and modulated H3 and H4 acetylation levels. Conclusions These results showed that intrauterine exposure to GBR-influenced metabolic outcomes in offspring of rats with underlying epigenetic changes and transcriptional implications that led to improved glucose homeostasis. PMID:26842399

  2. Phenotypic plasticity in cell walls of maize brown midrib mutants is limited by lignin composition

    PubMed Central

    Vermerris, Wilfred; Sherman, Debra M.; McIntyre, Lauren M.

    2010-01-01

    The hydrophobic cell wall polymer lignin is deposited in specialized cells to make them impermeable to water and prevent cell collapse as negative pressure or gravitational force is exerted. The variation in lignin subunit composition that exists among different species, and among different tissues within the same species suggests that lignin subunit composition varies depending on its precise function. In order to gain a better understanding of the relationship between lignin subunit composition and the physico-chemical properties of lignified tissues, detailed analyses were performed of near-isogenic brown midrib2 (bm2), bm4, bm2-bm4, and bm1-bm2-bm4 mutants of maize. This investigation was motivated by the fact that the bm2-bm4 double mutant is substantially shorter, displays drought symptoms even when well watered, and will often not develop reproductive organs, whereas the phenotypes of the individual bm single mutants and double mutant combinations other than bm2-bm4 are only subtly different from the wild-type control. Detailed cell wall compositional analyses revealed midrib-specific reductions in Klason lignin content in the bm2, bm4, and bm2-bm4 mutants relative to the wild-type control, with reductions in both guaiacyl (G)- and syringyl (S)-residues. The cellulose content was not different, but the reduction in lignin content was compensated by an increase in hemicellulosic polysaccharides. Linear discriminant analysis performed on the compositional data indicated that the bm2 and bm4 mutations act independently of each other on common cell wall biosynthetic steps. After quantitative analysis of scanning electron micrographs of midrib sections, the variation in chemical composition of the cell walls was shown to be correlated with the thickness of the sclerenchyma cell walls, but not with xylem vessel surface area. The bm2-bm4 double mutant represents the limit of phenotypic plasticity in cell wall composition, as the bm1-bm2-bm4 and bm2-bm3-bm4 mutants

  3. Antagonistic growth regulation by Dpp and Fat drives uniform cell proliferation.

    PubMed

    Schwank, Gerald; Tauriello, Gerardo; Yagi, Ryohei; Kranz, Elizabeth; Koumoutsakos, Petros; Basler, Konrad

    2011-01-18

    We use the Dpp morphogen gradient in the Drosophila wing disc as a model to address the fundamental question of how a gradient of a growth factor can produce uniform growth. We first show that proper expression and subcellular localization of components in the Fat tumor-suppressor pathway, which have been argued to depend on Dpp activity differences, are not reliant on the Dpp gradient. We next analyzed cell proliferation in discs with uniformly high Dpp or uniformly low Fat signaling activity and found that these pathways regulate growth in a complementary manner. While the Dpp mediator Brinker inhibits growth in the primordium primarily in the lateral regions, Fat represses growth mostly in the medial region. Together, our results indicate that the activities of both signaling pathways are regulated in a parallel rather than sequential manner and that uniform proliferation is achieved by their complementary action on growth.

  4. Comparisons of topical and spray applications of two pesticides, triazophos and jinggangmycin, on the protein content in the ovaries and fat bodies of the brown planthopper Nilaparvata lugens Stål (Hemiptera:Delphacidae).

    PubMed

    Zhu, Zhan-Fei; Cheng, Jia; Lu, Xiu-Li; Li, Xin; Ge, Lin-Quan; Fang, Ji-Chao; Wu, Jin-Cai

    2014-09-01

    The pesticide-induced stimulation of reproduction in pests is one of the most important mechanisms of pest resurgence. There have been numerous reports on the insecticide-induced stimulation of reproduction. However, the relationship between pesticide application method and pest resurgence (stimulation of reproduction) has received little attention. Here, we studied the effect of two treatment methods, triazophos (TZP) and jinggangmycin (JGM), on the protein content in the ovaries and fat bodies of the brown planthopper (BPH) Nilaparvata lugens Stål. The results showed that pesticide treatment methods significantly affected the protein content in the ovaries and fat bodies of BPH. In addition, grand means (means of main effect) of the protein content at 2 and 3 days after emergence (2 and 3 DAE) for foliar sprays was significantly higher than that observed after topical treatments, which increased by 23.9% (from 1.42 to 1.76) and 8.82% (from 4.42 to 4.81), respectively. No significant differences on the protein content in the ovaries and fat bodies for the JGM topical treatment were observed compared with controls. However, the protein content for JGM foliar sprays was significantly higher than that for the controls. The protein contents in both topical and spray treatments of TZP were significantly higher than those of the controls. Ovarian protein is mainly yolk protein. There is a positive correlation between ovarian protein content and the number of eggs laid. These findings show that foliar spray of the pesticides promotes the resurgence of BPH. Therefore, the foliar spray of some pesticides, such as JGM, should be avoided for the control of pests, which is the sideeffects of the fungicide on non-target insect pests' occurrence.

  5. Mature adipocyte-derived dedifferentiated fat cells can transdifferentiate into skeletal myocytes in vitro.

    PubMed

    Kazama, Tomohiko; Fujie, Masaki; Endo, Tuyoshi; Kano, Koichiro

    2008-12-19

    We have previously reported the establishment of preadipocyte cell lines, termed dedifferentiated fat (DFAT) cells, from mature adipocytes of various animals. DFAT cells possess long-term viability and can redifferentiate into adipocytes both in vivo and in vitro. Furthermore, DFAT cells can transdifferentiate into osteoblasts and chondrocytes under appropriate culture conditions. However, it is unclear whether DFAT cells are capable of transdifferentiating into skeletal myocytes, which is common in the mesodermal lineage. Here, we show that DFAT cells can be induced to transdifferentiate into skeletal myocytes in vitro. Myogenic induction of DFAT cells resulted in the expression of MyoD and myogenin, followed by cell fusion and formation of multinucleated cells expressing sarcomeric myosin heavy chain. These results indicate that DFAT cells derived from mature adipocytes can transdifferentiate into skeletal myocytes in vitro.

  6. Mature adipocyte-derived dedifferentiated fat cells can transdifferentiate into skeletal myocytes in vitro

    SciTech Connect

    Kazama, Tomohiko; Fujie, Masaki; Endo, Tuyoshi; Kano, Koichiro

    2008-12-19

    We have previously reported the establishment of preadipocyte cell lines, termed dedifferentiated fat (DFAT) cells, from mature adipocytes of various animals. DFAT cells possess long-term viability and can redifferentiate into adipocytes both in vivo and in vitro. Furthermore, DFAT cells can transdifferentiate into osteoblasts and chondrocytes under appropriate culture conditions. However, it is unclear whether DFAT cells are capable of transdifferentiating into skeletal myocytes, which is common in the mesodermal lineage. Here, we show that DFAT cells can be induced to transdifferentiate into skeletal myocytes in vitro. Myogenic induction of DFAT cells resulted in the expression of MyoD and myogenin, followed by cell fusion and formation of multinucleated cells expressing sarcomeric myosin heavy chain. These results indicate that DFAT cells derived from mature adipocytes can transdifferentiate into skeletal myocytes in vitro.

  7. Brown and white adipose tissues: intrinsic differences in gene expression and response to cold exposure in mice.

    PubMed

    Rosell, Meritxell; Kaforou, Myrsini; Frontini, Andrea; Okolo, Anthony; Chan, Yi-Wah; Nikolopoulou, Evanthia; Millership, Steven; Fenech, Matthew E; MacIntyre, David; Turner, Jeremy O; Moore, Jonathan D; Blackburn, Edith; Gullick, William J; Cinti, Saverio; Montana, Giovanni; Parker, Malcolm G; Christian, Mark

    2014-04-15

    Brown adipocytes dissipate energy, whereas white adipocytes are an energy storage site. We explored the plasticity of different white adipose tissue depots in acquiring a brown phenotype by cold exposure. By comparing cold-induced genes in white fat to those enriched in brown compared with white fat, at thermoneutrality we defined a "brite" transcription signature. We identified the genes, pathways, and promoter regulatory motifs associated with "browning," as these represent novel targets for understanding this process. For example, neuregulin 4 was more highly expressed in brown adipose tissue and upregulated in white fat upon cold exposure, and cell studies showed that it is a neurite outgrowth-promoting adipokine, indicative of a role in increasing adipose tissue innervation in response to cold. A cell culture system that allows us to reproduce the differential properties of the discrete adipose depots was developed to study depot-specific differences at an in vitro level. The key transcriptional events underpinning white adipose tissue to brown transition are important, as they represent an attractive proposition to overcome the detrimental effects associated with metabolic disorders, including obesity and type 2 diabetes.

  8. Brown-like adipose progenitors derived from human induced pluripotent stem cells: Identification of critical pathways governing their adipogenic capacity.

    PubMed

    Hafner, Anne-Laure; Contet, Julian; Ravaud, Christophe; Yao, Xi; Villageois, Phi; Suknuntha, Kran; Annab, Karima; Peraldi, Pascal; Binetruy, Bernard; Slukvin, Igor I; Ladoux, Annie; Dani, Christian

    2016-08-31

    Human induced pluripotent stem cells (hiPSCs) show great promise for obesity treatment as they represent an unlimited source of brown/brite adipose progenitors (BAPs). However, hiPSC-BAPs display a low adipogenic capacity compared to adult-BAPs when maintained in a traditional adipogenic cocktail. The reasons of this feature are unknown and hamper their use both in cell-based therapy and basic research. Here we show that treatment with TGFβ pathway inhibitor SB431542 together with ascorbic acid and EGF were required to promote hiPSCs-BAP differentiation at a level similar to adult-BAP differentiation. hiPSC-BAPs expressed the molecular identity of adult-UCP1 expressing cells (PAX3, CIDEA, DIO2) with both brown (ZIC1) and brite (CD137) adipocyte markers. Altogether, these data highlighted the critical role of TGFβ pathway in switching off hiPSC-brown adipogenesis and revealed novel factors to unlock their differentiation. As hiPSC-BAPs display similarities with adult-BAPs, it opens new opportunities to develop alternative strategies to counteract obesity.

  9. Brown-like adipose progenitors derived from human induced pluripotent stem cells: Identification of critical pathways governing their adipogenic capacity

    PubMed Central

    Hafner, Anne-Laure; Contet, Julian; Ravaud, Christophe; Yao, Xi; Villageois, Phi; Suknuntha, Kran; Annab, Karima; Peraldi, Pascal; Binetruy, Bernard; Slukvin, Igor I.; Ladoux, Annie; Dani, Christian

    2016-01-01

    Human induced pluripotent stem cells (hiPSCs) show great promise for obesity treatment as they represent an unlimited source of brown/brite adipose progenitors (BAPs). However, hiPSC-BAPs display a low adipogenic capacity compared to adult-BAPs when maintained in a traditional adipogenic cocktail. The reasons of this feature are unknown and hamper their use both in cell-based therapy and basic research. Here we show that treatment with TGFβ pathway inhibitor SB431542 together with ascorbic acid and EGF were required to promote hiPSCs-BAP differentiation at a level similar to adult-BAP differentiation. hiPSC-BAPs expressed the molecular identity of adult-UCP1 expressing cells (PAX3, CIDEA, DIO2) with both brown (ZIC1) and brite (CD137) adipocyte markers. Altogether, these data highlighted the critical role of TGFβ pathway in switching off hiPSC-brown adipogenesis and revealed novel factors to unlock their differentiation. As hiPSC-BAPs display similarities with adult-BAPs, it opens new opportunities to develop alternative strategies to counteract obesity. PMID:27577850

  10. Regeneration of fat cells from myofibroblasts during wound healing.

    PubMed

    Plikus, Maksim V; Guerrero-Juarez, Christian F; Ito, Mayumi; Li, Yun Rose; Dedhia, Priya H; Zheng, Ying; Shao, Mengle; Gay, Denise L; Ramos, Raul; Hsi, Tsai-Ching; Oh, Ji Won; Wang, Xiaojie; Ramirez, Amanda; Konopelski, Sara E; Elzein, Arijh; Wang, Anne; Supapannachart, Rarinthip June; Lee, Hye-Lim; Lim, Chae Ho; Nace, Arben; Guo, Amy; Treffeisen, Elsa; Andl, Thomas; Ramirez, Ricardo N; Murad, Rabi; Offermanns, Stefan; Metzger, Daniel; Chambon, Pierre; Widgerow, Alan D; Tuan, Tai-Lan; Mortazavi, Ali; Gupta, Rana K; Hamilton, Bruce A; Millar, Sarah E; Seale, Patrick; Pear, Warren S; Lazar, Mitchell A; Cotsarelis, George

    2017-02-17

    Although regeneration through the reprogramming of one cell lineage to another occurs in fish and amphibians, it has not been observed in mammals. We discovered in the mouse that during wound healing, adipocytes regenerate from myofibroblasts, a cell type thought to be differentiated and nonadipogenic. Myofibroblast reprogramming required neogenic hair follicles, which triggered bone morphogenetic protein (BMP) signaling and then activation of adipocyte transcription factors expressed during development. Overexpression of the BMP antagonist Noggin in hair follicles or deletion of the BMP receptor in myofibroblasts prevented adipocyte formation. Adipocytes formed from human keloid fibroblasts either when treated with BMP or when placed with human hair follicles in vitro. Thus, we identify the myofibroblast as a plastic cell type that may be manipulated to treat scars in humans.

  11. Antrodia camphorata Grown on Germinated Brown Rice Suppresses Melanoma Cell Proliferation by Inducing Apoptosis and Cell Differentiation and Tumor Growth

    PubMed Central

    Song, Minjung; Park, Dong Ki; Park, Hye-Jin

    2013-01-01

    Antrodia camphorata grown on germinated brown rice (CBR) was prepared to suppress melanoma development. CBR extracts were divided into hexane, EtOAc, BuOH, and water fractions. Among all the fractions, EtOAc fraction showed the best suppressive effect on B16F10 melanoma cell proliferation by CCK-8 assay. It also showed the increased cell death and the changed cellular morphology after CBR treatment. Annexin V-FITC/PI, flow cytometry, and western blotting were performed to elucidate anticancer activity of CBR. The results showed that CBR induced p53-mediated apoptotic cell death of B16F10. CBR EtOAc treatment increased melanin content and melanogenesis-related proteins of MITF and TRP-1 expressions, which supports its anticancer activity. Its potential as an anticancer agent was further investigated in tumor-xenografted mouse model. In melanoma-xenografted mouse model, melanoma tumor growth was significantly suppressed under CBR EtOAc fraction treatment. HPLC analysis of CBR extract showed peak of adenosine. In conclusion, CBR extracts notably inhibited B16F10 melanoma cell proliferation through the p53-mediated apoptosis induction and increased melanogenesis. These findings suggest that CBR EtOAc fraction can act as an effective anticancer agent to treat melanoma. PMID:23533475

  12. Adipocyte Lineages: Tracing Back the Origins of Fat

    PubMed Central

    Sanchez-Gurmaches, Joan; Guertin, David A.

    2013-01-01

    Summary The obesity epidemic has intensified efforts to understand the mechanisms controlling adipose tissue development. Adipose tissue is generally classified as white adipose tissue (WAT), the major energy storing tissue, or brown adipose tissue (BAT), which mediates non-shivering thermogenesis. It is hypothesized that brite adipocytes (brown in white) may represent a third adipocyte class. The recent realization that brown fat exist in adult humans suggests increasing brown fat energy expenditure could be a therapeutic strategy to combat obesity. To understand adipose tissue development, several groups are tracing the origins of mature adipocytes back to their adult precursor and embryonic ancestors. From these studies emerged a model that brown adipocytes originate from a precursor shared with skeletal muscle that expresses Myf5-Cre, while all white adipocytes originate from a Myf5-negative precursors. While this provided a rational explanation to why BAT is more metabolically favorable than WAT, recent work indicates the situation is more complex because subsets of white adipocytes also arise from Myf5-Cre expressing precursors. Lineage tracing studies further suggest that the vasculature may provide a niche supporting both brown and white adipocyte progenitors; however, the identity of the adipocyte progenitor cell is under debate. Differences in origin between adipocytes could explain metabolic heterogeneity between depots and/or influence body fat patterning particularly in lipodystrophy disorders. Here, we discuss recent insights into adipose tissue origins highlighting lineage-tracing studies in mice, how variations in metabolism or signaling between lineages could affect body fat distribution, and the questions that remain unresolved. PMID:23747579

  13. Hematopoietic stem cells burn fat to prevent exhaustion.

    PubMed

    Lallemand-Breitenbach, Valerie; de Thé, Hugues

    2012-10-05

    Ito et al. (2012) recently report in Nature Medicine that fatty acid oxidation (FAO) regulated by PPARδ controls asymmetric division in hematopoietic stem cells (HSCs). This metabolic mechanism prevents HSC exhaustion and is downstream of the promyelocytic leukemia protein PML, suggesting therapeutic implications for HSC function and disease.

  14. Dchs1–Fat4 regulation of polarized cell behaviours during skeletal morphogenesis

    PubMed Central

    Mao, Yaopan; Kuta, Anna; Crespo-Enriquez, Ivan; Whiting, Danielle; Martin, Tina; Mulvaney, Joanna; Irvine, Kenneth D.; Francis-West, Philippa

    2016-01-01

    Skeletal shape varies widely across species as adaptation to specialized modes of feeding and locomotion, but how skeletal shape is established is unknown. An example of extreme diversity in the shape of a skeletal structure can be seen in the sternum, which varies considerably across species. Here we show that the Dchs1–Fat4 planar cell polarity pathway controls cell orientation in the early skeletal condensation to define the shape and relative dimensions of the mouse sternum. These changes fit a model of cell intercalation along differential Dchs1–Fat4 activity that drives a simultaneous narrowing, thickening and elongation of the sternum. Our results identify the regulation of cellular polarity within the early pre-chondrogenic mesenchyme, when skeletal shape is established, and provide the first demonstration that Fat4 and Dchs1 establish polarized cell behaviour intrinsically within the mesenchyme. Our data also reveal the first indication that cell intercalation processes occur during ventral body wall elongation and closure. PMID:27145737

  15. Quantitative analysis of rat adipose tissue cell recovery, and non-fat cell volume, in primary cell cultures

    PubMed Central

    Rotondo, Floriana; Romero, María del Mar; Ho-Palma, Ana Cecilia; Remesar, Xavier; Fernández-López, José Antonio

    2016-01-01

    Background White adipose tissue (WAT) is a complex, diffuse, multifunctional organ which contains adipocytes, and a large proportion of fat, but also other cell types, active in defense, regeneration and signalling functions. Studies with adipocytes often require their isolation from WAT by breaking up the matrix of collagen fibres; however, it is unclear to what extent adipocyte number in primary cultures correlates with their number in intact WAT, since recovery and viability are often unknown. Experimental Design Epididymal WAT of four young adult rats was used to isolate adipocytes with collagenase. Careful recording of lipid content of tissue, and all fraction volumes and weights, allowed us to trace the amount of initial WAT fat remaining in the cell preparation. Functionality was estimated by incubation with glucose and measurement of glucose uptake and lactate, glycerol and NEFA excretion rates up to 48 h. Non-adipocyte cells were also recovered and their sizes (and those of adipocytes) were measured. The presence of non-nucleated cells (erythrocytes) was also estimated. Results Cell numbers and sizes were correlated from all fractions to intact WAT. Tracing the lipid content, the recovery of adipocytes in the final, metabolically active, preparation was in the range of 70–75%. Cells showed even higher metabolic activity in the second than in the first day of incubation. Adipocytes were 7%, erythrocytes 66% and other stromal (nucleated cells) 27% of total WAT cells. However, their overall volumes were 90%, 0.05%, and 0.2% of WAT. Non-fat volume of adipocytes was 1.3% of WAT. Conclusions The methodology presented here allows for a direct quantitative reference to the original tissue of studies using isolated cells. We have also found that the “live cell mass” of adipose tissue is very small: about 13 µL/g for adipocytes and 2 µL/g stromal, plus about 1 µL/g blood (the rats were killed by exsanguination). These data translate (with respect to the

  16. Comparative Analysis of the miRNome of Bovine Milk Fat, Whey and Cells

    PubMed Central

    Li, Ran; Dudemaine, Pier-Luc; Zhao, Xin; Lei, Chuzhao; Ibeagha-Awemu, Eveline Mengwi

    2016-01-01

    Abundant miRNAs have been identified in milk and mammary gland tissues of different species. Typically, RNA in milk can be extracted from different fractions including fat, whey and cells and the mRNA transcriptome of milk could serve as an indicator of the transcriptome of mammary gland tissue. However, it has not been adequately validated if the miRNA transcriptome of any milk fraction could be representative of that of mammary gland tissue. The objectives of this study were to (1) characterize the miRNA expression spectra from three milk fractions- fat, whey and cells; (2) compare miRNome profiles of milk fractions (fat, whey and cells) with mammary gland tissue miRNome, and (3) determine which milk fraction miRNome profile could be a better representative of the miRNome profile of mammary gland tissue. Milk from four healthy Canadian Holstein cows in mid lactation was collected and fractionated. Total RNA extracted from each fraction was used for library preparation followed by small RNA sequencing. In addition, miRNA transcripts of mammary gland tissues from twelve Holstein cows in our previous study were used to compare our data. We identified 210, 200 and 249 known miRNAs from milk fat, whey and cells, respectively, with 188 universally expressed in the three fractions. In addition, 33, 31 and 36 novel miRNAs from milk fat, whey and cells were identified, with 28 common in the three fractions. Among 20 most highly expressed miRNAs in each fraction, 14 were expressed in common and 11 were further shared with mammary gland tissue. The three milk fractions demonstrated a clear separation from each other using a hierarchical cluster analysis with milk fat and whey being most closely related. The miRNome correlation between milk fat and mammary gland tissue (rmean = 0.866) was significantly higher than the other two pairs (p < 0.01), whey/mammary gland tissue (rmean = 0.755) and milk cell/mammary gland tissue (rmean = 0.75), suggesting that milk fat could be an

  17. Comparative Analysis of the miRNome of Bovine Milk Fat, Whey and Cells.

    PubMed

    Li, Ran; Dudemaine, Pier-Luc; Zhao, Xin; Lei, Chuzhao; Ibeagha-Awemu, Eveline Mengwi

    2016-01-01

    Abundant miRNAs have been identified in milk and mammary gland tissues of different species. Typically, RNA in milk can be extracted from different fractions including fat, whey and cells and the mRNA transcriptome of milk could serve as an indicator of the transcriptome of mammary gland tissue. However, it has not been adequately validated if the miRNA transcriptome of any milk fraction could be representative of that of mammary gland tissue. The objectives of this study were to (1) characterize the miRNA expression spectra from three milk fractions- fat, whey and cells; (2) compare miRNome profiles of milk fractions (fat, whey and cells) with mammary gland tissue miRNome, and (3) determine which milk fraction miRNome profile could be a better representative of the miRNome profile of mammary gland tissue. Milk from four healthy Canadian Holstein cows in mid lactation was collected and fractionated. Total RNA extracted from each fraction was used for library preparation followed by small RNA sequencing. In addition, miRNA transcripts of mammary gland tissues from twelve Holstein cows in our previous study were used to compare our data. We identified 210, 200 and 249 known miRNAs from milk fat, whey and cells, respectively, with 188 universally expressed in the three fractions. In addition, 33, 31 and 36 novel miRNAs from milk fat, whey and cells were identified, with 28 common in the three fractions. Among 20 most highly expressed miRNAs in each fraction, 14 were expressed in common and 11 were further shared with mammary gland tissue. The three milk fractions demonstrated a clear separation from each other using a hierarchical cluster analysis with milk fat and whey being most closely related. The miRNome correlation between milk fat and mammary gland tissue (rmean = 0.866) was significantly higher than the other two pairs (p < 0.01), whey/mammary gland tissue (rmean = 0.755) and milk cell/mammary gland tissue (rmean = 0.75), suggesting that milk fat could be an

  18. Gamma delta T cells promote inflammation and insulin resistance during high fat diet-induced obesity in mice

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Gamma delta T cells are resident in adipose tissue and increase during diet-induced obesity. Their possible contribution to the inflammatory response that accompanies diet-induced obesity was investigated in mice after a 5-10 week high milk fat diet. The high milk fat diet resulted in significant in...

  19. Pancreatic Fat Is Associated With Metabolic Syndrome and Visceral Fat but Not Beta-Cell Function or Body Mass Index in Pediatric Obesity

    PubMed Central

    Staaf, Johan; Labmayr, Viktor; Paulmichl, Katharina; Manell, Hannes; Cen, Jing; Ciba, Iris; Dahlbom, Marie; Roomp, Kirsten; Anderwald, Christian-Heinz; Meissnitzer, Matthias; Schneider, Reinhard; Forslund, Anders; Widhalm, Kurt; Bergquist, Jonas; Ahlström, Håkan; Bergsten, Peter; Weghuber, Daniel; Kullberg, Joel

    2017-01-01

    Objective Adolescents with obesity have increased risk of type 2 diabetes and metabolic syndrome (MetS). Pancreatic fat has been related to these conditions; however, little is known about associations in pediatric obesity. The present study was designed to explore these associations further. Methods We examined 116 subjects, 90 with obesity. Anthropometry, MetS, blood samples, and oral glucose tolerance tests were assessed using standard techniques. Pancreatic fat fraction (PFF) and other fat depots were quantified using magnetic resonance imaging. Results The PFF was elevated in subjects with obesity. No association between PFF and body mass index-standard deviation score (BMI-SDS) was found in the obesity subcohort. Pancreatic fat fraction correlated to Insulin Secretion Sensitivity Index-2 and Homeostatic Model Assessment of Insulin Resistance in simple regression; however, when using adjusted regression and correcting for BMI-SDS and other fat compartments, PFF correlated only to visceral adipose tissue and fasting glucose. Highest levels of PFF were found in subjects with obesity and MetS. Conclusions In adolescents with obesity, PFF is elevated and associated to MetS, fasting glucose, and visceral adipose tissue but not to beta-cell function, glucose tolerance, or BMI-SDS. This study demonstrates that conclusions regarding PFF and its associations depend on the body mass features of the cohort. PMID:27941426

  20. Viability of fat cells over time after syringe suction lipectomy: the effects of cryopreservation.

    PubMed

    Son, Daegu; Oh, Jaehoon; Choi, Taehyun; Kim, Junhyung; Han, Kihwan; Ha, Seongyun; Lee, Kyungho

    2010-09-01

    The purpose of this study was to determine the late decline in viability of fat cells over time for fat tissue stored at -15 degrees C and -70 degrees C after harvest from abdominal liposuction. A total of 16 females were recruited for this study. The viability of fat cell specimens was measured after freezing for 1, 3, 7, 14, 28, and 56 days. A number of viable mature adipocytes were evaluated by fluorescence microscopy after staining with fluorescein diacetate and propidium iodide. The glycerol-3-phosphate dehydrogenase activity was measured in lipoaspirates before digestion and the XTT reduction assay was performed. In addition, the XTT reduction assay was also performed on isolated lipocytes and preadipocytes.The viability of mature adipocytes was very low for both the -15 degrees C and -70 degrees C samples after 1 day of freezing (13.3% +/- 7.4% and 12.6% +/- 6.3%, respectively). There was no statistically significant difference between the samples stored at the 2 temperatures. The GPDH activity of the lipoaspirates frozen, for 1 day, at -15 degrees C and -70 degrees C was 25.1% +/- 10% and 28.7% +/- 11%, respectively. For the XTT test, the fractional enzyme activity of the lipoaspirates frozen, for 1 day, at -15 degrees C and -70 degrees C was 30.0% +/- 10.9% and 36.1% +/- 12.3%, respectively. In addition, the adipocytes had low activity from day one: 15.4% +/- 7.2% at -15 degrees C and 11.5% +/- 5.6% at -70 degrees C. Furthermore, the preadipocytes had a low activity of 8.0% +/- 6.0% at -15 degrees C and 8.6% +/- 3.8% at -70 degrees C. At 8 weeks, there were few viable mature adipocytes and the activity of the cells was very low by XTT and GPDH testing.The results of this study showed that the viability of adipocytes declined rapidly after frozen storage for 1 day at both -15 degrees C and -70 degrees C, and decreased gradually in storage after 8 weeks; at which time only approximately 5% of the fat cells were alive. These findings suggest that the present

  1. Survival and Inflammatory Response in Adipose-derived Mesenchymal Stem Cell-enriched Mouse Fat Grafts

    PubMed Central

    Begic, Anadi; Isfoss, Björn L.; Lønnerød, Linn K.; Vigen, Alexander

    2016-01-01

    Background: Adipose tissue-derived mesenchymal stem cells (ATMSCs) are currently used in grafting procedures in a number of clinical trials. The reconstructive role of such cells in fat graft enrichment is largely unclear. This study was undertaken to assess survival and inflammatory response in fat grafts enriched with ATMSCs in mice. Methods: ATMSC-enriched adipose tissue was grafted subcutaneously in a clinically relevant manner in mice, and survival and inflammatory response were determined by bioluminescence imaging of transgenic tissue constitutively expressing luciferase or driven by inflammation in wild-type animals. Results: Only a minor fraction of ATMSCs transplanted subcutaneously were found to survive long term, yet fat grafts enriched with ATMSCs showed improved survival for a limited period, compared with no enrichment. NF-κB activity was transiently increased in ATMSC-enriched grafts, and the grafts responded adequately to a proinflammatory stimulus. In one animal, cells originating from the subcutaneous graft were found at a site of inflammation distant from the site of engraftment. Conclusion: ATMSCs display limited subcutaneous survival. Still, ATMSC enrichment may improve the outcome of adipose tissue grafting procedures by facilitating short-term graft survival and adequate inflammatory responses. Migration of cells from grafted adipose tissue requires further investigation. PMID:28293494

  2. Cloning and characterization of adipogenin and its overexpression enhances fat accumulation of bovine myosatellite cells.

    PubMed

    Liu, Yang; Jiang, Bijie; Fu, Changzhen; Hao, Ruijie

    2017-02-15

    Adipogenin (ADIG) is an adipocyte-specific membrane protein highly expressed in adipose tissues and is increased during the adipocyte differentiation. However, the roles and mechanisms of ADIG on fat accumulation and adipocyte differentiation in ex vivo still largely unknown. In this study, we isolated bovine myosatellite cells based on adhesion characteristics to investigate whether ADIG overexpression could promote trans-differentiation and increase fat accumulation in myosatellite cells. Immunofluorescence labeling was then used for the phenotypic characteristics of myosatellite. Our results showed that, after induction of differentiation, adenovirus mediated ADIG overexpression could upregulate expression level of PPARγ, and Oil Red O staining showed larger lipid drops compared to control groups. In consistent, key components of Hh signaling pathway were down regulated when infected with ADIG adenovirus, even though treated with inhibitor of Hh signaling pathway together could not induce further decrease. In addition, bioinformatics analysis of ADIG was also performed for its structure and function.

  3. Advantages of Sheep Infrapatellar Fat Pad Adipose Tissue Derived Stem Cells in Tissue Engineering

    PubMed Central

    Vahedi, Parviz; Soleimanirad, Jafar; Roshangar, Leila; Shafaei, Hajar; Jarolmasjed, Seyedhosein; Nozad Charoudeh, Hojjatollah

    2016-01-01

    Purpose: The goal of this study has been to evaluate adipose tissue derived stem cells (ADSCs) from infrapatellar fat pad and characterize their cell surface markers using anti-human antibodies, as adipose tissue derived stem cells (ADSCs) have great potential for cellular therapies to restore injured tissues. Methods: Adipose tissue was obtained from infrapatellar fat pad of sheep. Surface markers evaluated by flow cytometry. In order to evaluate cell adhesion, the Polycaprolactone (PCL) was sterilized under Ultraviolet (UV) light and about 1×105 cells were seeded on PCL. Then, ASCs- PCL construct were evaluated by Scanning Electron Microscopy (Mira3 Te Scan, Czech Republic). Results: We showed that adipose tissue derived stem cells (ADSCs) maintain their fibroblastic-like morphology during different subcultures and cell adhesion. They were positive for CD44 and CD90 markers and negative for CD31 and Cd45 markers by human antibodies. Conclusion: Our results suggest that ASCs surface markers can be characterized by anti-human antibodies in sheep. As stem cells, they can be used in tissue engineering. PMID:27123425

  4. Dedifferentiated fat cells convert to cardiomyocyte phenotype and repair infarcted cardiac tissue in rats.

    PubMed

    Jumabay, Medet; Matsumoto, Taro; Yokoyama, Shin-ichiro; Kano, Koichiro; Kusumi, Yoshiaki; Masuko, Takayuki; Mitsumata, Masako; Saito, Satoshi; Hirayama, Atsushi; Mugishima, Hideo; Fukuda, Noboru

    2009-11-01

    Adipose tissue-derived stem cells have been demonstrated to differentiate into cardiomyocytes and vascular endothelial cells. Here we investigate whether mature adipocyte-derived dedifferentiated fat (DFAT) cells can differentiate to cardiomyocytes in vitro and in vivo by establishing DFAT cell lines via ceiling culture of mature adipocytes. DFAT cells were obtained by dedifferentiation of mature adipocytes from GFP-transgenic rats. We evaluated the differentiating ability of DFAT cells into cardiomyocytes by detection of the cardiac phenotype markers in immunocytochemical and RT-PCR analyses in vitro. We also examined effects of the transplantation of DFAT cells into the infarcted heart of rats on cardiomyocytes regeneration and angiogenesis. DFAT cells expressed cardiac phenotype markers when cocultured with cardiomyocytes and also when grown in MethoCult medium in the absence of cardiomyocytes, indicating that DFAT cells have the potential to differentiate to cardiomyocyte lineage. In a rat acute myocardial infarction model, transplanted DFAT cells were efficiently accumulated in infarcted myocardium and expressed cardiac sarcomeric actin at 8 weeks after the cell transplantation. The transplantation of DFAT cells significantly (p<0.05) increased capillary density in the infarcted area when compared with hearts from saline-injected control rats. We demonstrated that DFAT cells have the ability to differentiate to cardiomyocyte-like cells in vitro and in vivo. In addition, transplantation of DFAT cells led to neovascuralization in rats with myocardial infarction. We propose that DFAT cells represent a promising candidate cell source for cardiomyocyte regeneration in severe ischemic heart disease.

  5. Oxygen deprivation and the cellular response to hypoxia in adipocytes - perspectives on white and brown adipose tissues in obesity.

    PubMed

    Trayhurn, Paul; Alomar, Suliman Yousef

    2015-01-01

    Relative hypoxia has been shown to develop in white adipose tissue depots of different types of obese mouse (genetic, dietary), and this leads to substantial changes in white adipocyte function. These changes include increased production of inflammation-related adipokines (such as IL-6, leptin, Angptl4, and VEGF), an increase in glucose utilization and lactate production, and the induction of fibrosis and insulin resistance. Whether hypoxia also occurs in brown adipose tissue depots in obesity has been little considered. However, a recent study has reported low pO2 in brown fat of obese mice, this involving mitochondrial loss and dysfunction. We suggest that obesity-linked hypoxia may lead to similar alterations in brown adipocytes as in white fat cells - particularly changes in adipokine production, increased glucose uptake and lactate release, and insulin resistance. This would be expected to compromise thermogenic activity and the role of brown fat in glucose homeostasis and triglyceride clearance, underpinning the development of the metabolic syndrome. Hypoxia-induced augmentation of lactate production may also stimulate the "browning" of white fat depots through recruitment of UCP1 and the development of brite adipocytes.

  6. Renin-angiotensin system blockers regulate the metabolism of isolated fat cells in vitro

    PubMed Central

    Caminhotto, R de O.; Sertié, R.A.L.; Andreotti, S.; Campaãa, A.B.; Lima, F.B.

    2016-01-01

    Due to the presence of the renin-angiotensin system (RAS) in tissues and its specific influence on white adipose tissue, fat cells are possible targets of pharmacological RAS blockers commonly used as anti-hypertensive drugs. In the present study, we investigated the effects of different RAS blockers on fat cell metabolism, more specifically on lipolysis, lipogenesis and oxidation of energy substrates. Isolated primary adipocytes were incubated with different RAS blockers (aliskiren, captopril and losartan) in vitro for 24 h and lipolysis, lipogenesis and glucose oxidation capacities were determined in dose-response assays to a β-adrenergic agonist and to insulin. Although no change was found in lipolytic capacity, the RAS blockers modulated lipogenesis and glucose oxidation in a different way. While captopril decreased insulin-stimulated lipogenesis (−19% of maximal response and −60% of insulin responsiveness) due to reduced glucose derived glycerol synthesis (−19% of maximal response and 64% of insulin responsiveness), aliskiren increased insulin-stimulated glucose oxidation (+49% of maximal response and +292% of insulin responsiveness) in fat cells. Our experiments demonstrate that RAS blockers can differentially induce metabolic alterations in adipocyte metabolism, characterized by a reduction in lipogenic responsiveness or an increase in glucose oxidation. The impact of RAS blockers on adipocyte metabolism may have beneficial implications on metabolic disorders during their therapeutic use in hypertensive patients. PMID:27487419

  7. Competition in newborn rabbits for thermally advantageous positions in the litter huddle is associated with individual differences in brown fat metabolism.

    PubMed

    Bautista, Amando; Castelán, Francisco; Pérez-Roldán, Humberto; Martínez-Gómez, Margarita; Hudson, Robyn

    2013-06-13

    The altricial young of the European rabbit (Oryctolagus cuniculus) are not brooded by the mother, and although they are born into an underground nest, depend importantly on the warmth and insulation provided by littermates for their early growth and survival. Consistent with previous studies, heavier pups occupied more central, thermally advantageous positions in the litter huddle, maintained higher body temperatures, obtained more milk, were more efficient at converting it to body mass, and consequently grew faster than their lighter sibs occupying the periphery of the huddle. In the present study we measured the expression of uncoupling protein 1 (UCP-1), which is essential for the metabolism of brown adipose tissue to generate body heat in response to cold. In nine litters of domestic rabbits maintained for the first four postnatal days at temperatures below their critical thermoneutral temperature, peripheral pups showed greater expression of UCP-1 than intermediate pups, and these greater expression than central pups. This suggests that during early development littermates of the rabbit experience differing degrees of activation of the sympathetic nervous system as a consequence of exposure to different thermal environments associated with different positions in the litter huddle. Whether this is associated with long term differences in the physiological response to cold and perhaps in the manner of responding to other environmental challenges is currently under investigation.

  8. Insulin-like actions of nickel and other transition-metal ions in rat fat-cells.

    PubMed

    Saggerson, E D; Sooranna, S R; Evans, C J

    1976-02-15

    NiC12 (1-6mM) decreased adrenaline and glucagon-stimulated lipolysis in rat fat-cells, and also considerably stimulated [U-14C]glucose incorporation into fat-cell lipids. 2. These insulin-like effects were also observed with CuCl, CuCl2, CoCl2 and (to a lesser extent) with MnCl2. 3. NiCl2 was less effective in mimicking insulin effects on [U-14C]fructose metabolism than on glucose utilization. 4. It is tentatively suggested that these transition-metal ions may mimic actions of insulin at the fat-cell plasma membrane which decrease lipolysis and stimulate glucose transport, but do not mimic certain other effects of the hormone on intracellular metabolic processes. 5. These results are discussed with reference to suggestions that redistributions of cellular Ca2+ are associated with insulin action in fat-cells.

  9. Dietary fat and risk of renal cell carcinoma in the USA: a case–control study

    PubMed Central

    Brock, Kaye E.; Gridley, Gloria; Chiu, Brian C.-H.; Ershow, Abby G.; Lynch, Charles F.; Cantor, Kenneth P.

    2011-01-01

    An increased risk of renal cell carcinoma (RCC) has been linked with obesity. However, there is limited information about the contribution of dietary fat and fat-related food groups to RCC risk. A population-based case–control study of 406 cases and 2434 controls aged 40–85 years was conducted in Iowa (1986–89). For 323 cases and 1820 controls from the present study, information on dietary intake from foods high in fat nutrients and other lifestyle factors was obtained using a mailed questionnaire. Cancer risks were estimated by OR and 95 % CI, adjusting for age, sex, smoking, obesity, hypertension, physical activity, alcohol and vegetable intake and tea and coffee consumption. In all nutrient analyses, energy density estimates were used. Dietary nutrient intake of animal fat, saturated fat, oleic acid and cholesterol was associated with an elevated risk of RCC (OR = 1·9, 95 % CI 1·3, 2·9, Ptrend < 0·001; OR = 2·6, 95 % CI 1·6, 4·0, Ptrend < 0·001; OR = 1·9, 95 % CI 1·2, 2·9, Ptrend = 0·01; OR = 1·9, 95 % CI 1·3, 2·8, Ptrend = 0·006, respectively, for the top quartile compared with the bottom quartile of intake). Increased risks were also associated with high-fat spreads, red and cured meats and dairy products (OR = 2·0, 95 % CI 1·4, 3·0, Ptrend = 0·001; OR = 1·7, 95 % CI 1·0, 2·2, Ptrend = 0·01; OR = 1·8, 95 % CI 1·2, 2·7, Ptrend = 0·02; OR = 1·6, 95 % CI 1·1, 2·3, Ptrend = 0·02, respectively). In both the food groups and nutrients, there was a significant dose–response with increased intake. Our data also indicated that the association of RCC with high-fat spreads may be stronger among individuals with hypertension. These findings deserve further investigation in prospective studies. PMID:18786276

  10. Human fat cell alpha-2 adrenoceptors. I. Functional exploration and pharmacological definition with selected alpha-2 agonists and antagonists

    SciTech Connect

    Galitzky, J.; Mauriege, P.; Berlan, M.; Lafontan, M.

    1989-05-01

    This study was undertaken to investigate more fully the pharmacological characteristics of the human fat cell alpha-2 adrenoceptor. Biological assays were performed on intact isolated fat cells while radioligand binding studies were carried out with (/sup 3/H)yohimbine in membranes. These pharmacological studies brought: (1) a critical definition of the limits of the experimental conditions required for the exploration of alpha-2 adrenergic responsiveness on human fat cells and membranes; (2) an improvement in the pharmacological definition of the human fat cell postsynaptic alpha-2 adrenoceptor. Among alpha-2 agonists, UK-14,304 was the most potent and the relative order of potency was: UK-14,304 greater than p-aminoclonidine greater than clonidine = B-HT 920 greater than rilmenidine. For alpha-2 antagonists, the potency order was: yohimbine greater than idazoxan greater than SK F-86,466 much greater than benextramine; (3) a description of the impact of benextramine (irreversible alpha-1/alpha-2 antagonist) on human fat cell alpha-2 adrenergic receptors and on human fat cell function; the drug inactivates the alpha-2 adrenergic receptors with a minor impact on beta adrenergic receptors and without noticeable alterations of fat cell function as assessed by preservation of beta adrenergic and Al-adenosine receptor-mediated lipolytic responses; and (4) a definition of the relationship existing between alpha-2 adrenergic receptor occupancy, inhibition of adenylate cyclase activity and antilipolysis with full and partial agonists. The existence of a receptor reserve must be taken into account when evaluating alpha-2 adrenergic receptor distribution and regulation of human fat cells.

  11. Pharmacological and Genetic Manipulation of p53 in Brown Fat at Adult But Not Embryonic Stages Regulates Thermogenesis and Body Weight in Male Mice.

    PubMed

    Al-Massadi, Omar; Porteiro, Begoña; Kuhlow, Doreen; Köhler, Markus; Gonzalez-Rellan, María J; Garcia-Lavandeira, Montserrat; Díaz-Rodríguez, Esther; Quiñones, Mar; Senra, Ana; Alvarez, Clara V; López, Miguel; Diéguez, Carlos; Schulz, Tim J; Nogueiras, Rubén

    2016-07-01

    p53 is a well-known tumor suppressor that plays multiple biological roles, including the capacity to modulate metabolism at different levels. However, its metabolic role in brown adipose tissue (BAT) remains largely unknown. Herein we sought to investigate the physiological role of endogenous p53 in BAT and its implication on BAT thermogenic activity and energy balance. To this end, we generated and characterized global p53-null mice and mice lacking p53 specifically in BAT. Additionally we performed gain-and-loss-of-function experiments in the BAT of adult mice using virogenetic and pharmacological approaches. BAT was collected and analyzed by immunohistochemistry, thermography, real-time PCR, and Western blot. p53-deficient mice were resistant to diet-induced obesity due to increased energy expenditure and BAT activity. However, the deletion of p53 in BAT using a Myf5-Cre driven p53 knockout did not show any changes in body weight or the expression of thermogenic markers. The acute inhibition of p53 in the BAT of adult mice slightly increased body weight and inhibited BAT thermogenesis, whereas its overexpression in the BAT of diet-induced obese mice reduced body weight and increased thermogenesis. On the other hand, pharmacological activation of p53 improves body weight gain due to increased BAT thermogenesis by sympathetic nervous system in obese adult wild-type mice but not in p53(-/-) animals. These results reveal that p53 regulates BAT metabolism by coordinating body weight and thermogenesis, but these metabolic actions are tissue specific and also dependent on the developmental stage.

  12. Thermogenic activity of UCP1 in human white fat-derived beige adipocytes.

    PubMed

    Bartesaghi, Stefano; Hallen, Stefan; Huang, Li; Svensson, Per-Arne; Momo, Remi A; Wallin, Simonetta; Carlsson, Eva K; Forslöw, Anna; Seale, Patrick; Peng, Xiao-Rong

    2015-01-01

    Heat-producing beige/brite (brown-in-white) adipocytes in white adipose tissue have the potential to suppress metabolic disease in mice and hold great promise for the treatment of obesity and type 2 diabetes in humans. Here, we demonstrate that human adipose-derived stromal/progenitor cells (hASCs) from subcutaneous white adipose tissue can be efficiently converted into beige adipocytes. Upon pharmacological activation of peroxisome proliferator-activated receptor-γ, hASC-derived adipocytes activated beige fat-selective genes and a brown/beige fat-selective electron transport chain gene program. Importantly, hASC-derived beige fat cells displayed the bioenergetic characteristics of genuine brown fat cells, including a capacity for increased respiratory uncoupling in response to β-adrenergic agonists. Furthermore, knock-down experiments reveal that the thermogenic capacity of human beige fat cells was entirely dependent on the presence of Uncoupling protein 1. In summary, this study reveals that hASCs can be readily differentiated into beige adipocytes that, upon activation, undergo uncoupling protein 1-dependent thermogenesis.

  13. Changes in human bone marrow fat content associated with changes in hematopoietic stem cell numbers and cytokine levels with aging.

    PubMed

    Tuljapurkar, Sonal R; McGuire, Timothy R; Brusnahan, Susan K; Jackson, John D; Garvin, Kevin L; Kessinger, Margaret A; Lane, Judy T; O' Kane, Barbara J; Sharp, John G

    2011-11-01

    Hematological deficiencies increase with aging, including anemias, reduced responses to hematopoietic stress and myelodysplasias. This investigation tested the hypothesis that increased bone marrow (BM) fat content in humans with age was associated with decreased numbers of side population (SP) hematopoietic stem cells, and this decrease correlated with changes in cytokine levels. BM was obtained from the femoral head and trochanteric region of the femur removed at surgery for total hip replacement (N = 100 subjects). In addition, BM from cadavers (N = 36), with no evidence of hip disease, was evaluated for fat content. Whole trabecular marrow samples were ground in a sterile mortar and pestle, and cellularity and lipid content determined. Marrow cells were stained with Hoechst dye and SP profiles were acquired. Plasma levels of insulin-like growth factor (IGF)-1, stromal-derived factor (SDF)-1 and interleukin (IL)-6 were measured using ELISA. Fat content in the BM of human subjects and cadavers increased with age. The numbers of SP stem cells in BM as well as plasma IGF-1 and SDF-1 levels decreased in correlation with increased BM fat. IL-6 had no relationship to changes in marrow fat. These data suggest that increased BM fat may be associated with a decreased number of SP stem cells and IGF-1 and SDF-1 levels with aging. These data further raise a more general question as to the role of adipose cells in the regulation of tissue stem cells.

  14. G/sub o/ protein of fat cells: role in hormonal regulation of agonist-stimulated phosphatidyl inositol breakdown

    SciTech Connect

    Rapiejko, P.J.; Northup, J.K.; Malbon, C.C.

    1986-05-01

    Incubating rat fat cell membranes in the presence of (/sup 32/P)NAD/sup +/ and pertussis toxin (PT) results in the ADP-ribosylation of two peptides (M/sub r/ = 41,000 and 40,000). The 41,000-M/sub r/ peptide is the inhibitory G-protein of adenylate cyclase (G/sub i/). The 40,000-M/sub r/ peptide radiolabeled in the presence of (/sup 32/P)NAD/sup +/ and PT has been purified from rabbit heart and bovine brain, but has not been identified uniformly in membranes of fat cells. Two rabbit polyclonal antisera raised against the alpha-subunit of bovine brain G/sub o/ were used to probe the nature of the 40,000-M/sub r/ peptide in rat fat cell membranes that had been separated by gel electrophoresis in the presence of sodium dodecyl sulfate and transferred electrophoretically to nitrocellulose. Both antisera specific for the alpha-subunit of G/sub o/ recognized the M/sub r/ = 40,000 peptide of fat cells that is ADP-ribosylated in the presence of PT. PT treatment of rat fat cells blocks epinephrine-stimulated inositol 1,4,5 trisphosphate (IP/sub 3/) generation. The inhibition of IP/sub 3/ generation by PT suggests a role for either G/sub i/ or G/sub o/ in receptor-mediated phosphatidyl inositol breakdown in the rat fat cell.

  15. Effect of dietary cholesterol and fat on cell cholesterol transfer to postprandial plasma in hyperlipidemic men.

    PubMed

    Sutherland, Wayne H F; de Jong, Sylvia A; Walker, Robert J

    2007-10-01

    Postprandial chylomicrons are potent ultimate acceptors of cell membrane cholesterol and are believed to accelerate reverse cholesterol transport (RCT). We compared the effects of meals rich in polyunsaturated fat (PUFA) and either high (605 mg) or low (151 mg) in cholesterol and a meal rich in dairy fat (DF) in the form of cream on net in vitro transport of red blood cell (RBC) membrane cholesterol to 4 and 6 h postprandial plasma in eight normotriglyceridemic (NTG-H) and eight hypertriglyceridemic (HTG-H) men with mild to moderate hypercholesterolemia. In HTG-H men, cell cholesterol accumulation in 6-h postprandial plasma was significantly (P = 0.02) less after the PUFA-HC meal compared with the other meals. The significant (P < 0.001) increase in cell plus endogenous cholesterol accumulation in the triglyceride-rich lipoprotein (TRL) fraction of 4 h postprandial plasma incubated with RBC was significantly (P = 0.007) higher after the PUFA-HC meal compared with DF meal in HTG-H men. In NTG-H men, cholesterol accumulation in plasma and plasma lipoproteins in the presence and absence of RBC was not significantly affected by the type of meal ingested. These data suggest that addition of large amounts of cholesterol to a PUFA meal may impair diffusion-mediated transport of cell membrane cholesterol to postprandial plasma and that replacing DF with PUFA in a meal increases postprandial lipemia and may potentially increase cholesterol accumulation in atherogenic postprandial TRL in HTG-H men.

  16. Brown University.

    ERIC Educational Resources Information Center

    CAUSE/EFFECT, 1984

    1984-01-01

    The computing at Brown University was formalized in 1960. Computing history, current university computing, and a description of the Institute for Research in Information and Scholarship are discussed. The installation of a broadband communications network (BRUNET) was recently completed. (MLW)

  17. Molecular cloning, expression pattern analysis of porcine Rb1 gene and its regulatory roles during primary dedifferentiated fat cells adipogenic differentiation.

    PubMed

    Hu, Xiaoming; Luo, Pei; Peng, Xuewu; Song, Tongxing; Zhou, Yuanfei; Wei, Hongkui; Peng, Jian; Jiang, Siwen

    2015-04-01

    Adipocytes are the main constituent of adipose tissue and are considered to be a corner stone in the homeostatic control of whole body metabolism. Recent reports evidenced that retinoblastoma 1 (Rb1) gene plays an important role in fat development and adipogenesis in mice. Here, we cloned the partial cDNA sequences of the porcine Rb1 gene which contains the complete coding sequences (CDS) of 2820bp encoding a protein of 939 amino acids. Bioinformatic analysis revealed that the CDS of porcine Rb1 was highly identical with those of cattle, human and mice. The porcine Rb1 has three typical conserved structural domains, including Rb-A pocket domain, CYCLIN domain and C-terminus domain, and the phylogenetic tree indicates a closer genetic relationship with cattle and human. Tissue distribution analysis showed that Rb1 expression appeared to be ubiquitously in various tissues, being higher in heart, liver, muscle, and stomach. Furthermore, significant downregulation of Rb1 was found at the initial stage of dedifferentiated fat (DFAT) cells adipogenic differentiation. With the knockdown of the Rb1 expression by siRNA, the number of DFAT cells recruited to white rather than brown adipogenesis was promoted, and mRNA levels of adipogenic markers, such as PPARγ, aP2, LPL and adiponectin and protein expression of PPARγ and adiponectin were increased after hormone stimulation. The underlying mechanisms may be that knockdown of Rb1 promotes the mitotic clonal expansion and PPARγ expression by derepressing the transcriptional activity of E2F so as to facilitate the first steps of adipogenesis. In summary, we cloned and characterized an important negative regulator in adipogenic commitment of porcine DFAT cells.

  18. Chondrogenic Potency Analyses of Donor-Matched Chondrocytes and Mesenchymal Stem Cells Derived from Bone Marrow, Infrapatellar Fat Pad, and Subcutaneous Fat

    PubMed Central

    Garcia, John; McCarthy, Helen S.; Roberts, Sally; Richardson, James B.

    2016-01-01

    Autologous chondrocyte implantation (ACI) is a cell-based therapy that has been used clinically for over 20 years to treat cartilage injuries more efficiently in order to negate or delay the need for joint replacement surgery. In this time, very little has changed in the ACI procedure, but now many centres are considering or using alternative cell sources for cartilage repair, in particular mesenchymal stem cells (MSCs). In this study, we have tested the chondrogenic potential of donor-matched MSCs derived from bone marrow (BM), infrapatellar fat pad (FP), and subcutaneous fat (SCF), compared to chondrocytes. We have confirmed that there is a chondrogenic potency hierarchy ranging across these cell types, with the most potent being chondrocytes, followed by FP-MSCs, BM-MSCs, and lastly SCF-MSCs. We have also examined gene expression and surface marker profiles in a predictive model to identify cells with enhanced chondrogenic potential. In doing so, we have shown that Sox-9, Alk-1, and Coll X expressions, as well as immunopositivity for CD49c and CD39, have predictive value for all of the cell types tested in indicating chondrogenic potency. The findings from this study have significant clinical implications for the refinement and development of novel cell-based cartilage repair strategies. PMID:27781068

  19. Improved adipogenic in vitro differentiation: comparison of different adipogenic cell culture media on human fat and bone stroma cells for fat tissue engineering.

    PubMed

    Ghoniem, Amir-Alexander; Açil, Yahya; Wiltfang, Jörg; Gierloff, Matthias

    2015-06-01

    To date there is no sufficient in vitro fat tissue engineering and a protocol has not been well established for this purpose. Therefore, we evaluated the in vitro influence of two different adipogenic growth media for their stimulation potential on different cell lineages to clearly define the most potent adipogenic growth media for future in vitro tissue engineering approaches. The samples for differentiation were composed of human adipogenic-derived stroma cells (hADSCs) and human bone marrow mesenchymal stroma cells (hMSCs). A normal adipogenic medium (NAM) and a specific adipogenic medium (SAM) were tested for their adipogenic stimulation potential. After 10 days and 21 days the relative gene expression was measured for the adipogenic marker genes PPARγ2, C/EBPα, FABP4, LPL, and GLUT4 detected through real time reverse transcriptase polymease chain reaction (RT-PCR). Other study variables were the comparison between NAM and SAM and between the used cells hADSCs and hMSCs. Additionally an Oil-Red staining was performed after 21 days. Our results revealed that only SAM was significantly (P<0.05) superior in the differentiation process in contrast to NAM for 10 days and 21 days. As well was SAM superior to differentiate the used cell lineages. This was evaluated by the detected marker genes PPARγ2, C/EBPα, FABP4, LPL, and GLUT4 through real time RT-PCR and by Oil-Red staining. In addition, the hMSCs proofed to be equal donor cells for adipogenic differentiation especially when stimulated by SAM. The results suggest that the SAM should be established as a new standard medium for a more promising in vitro adipogenic differentiation.

  20. High Fat Diets Induce Colonic Epithelial Cell Stress and Inflammation that is Reversed by IL-22

    PubMed Central

    Gulhane, Max; Murray, Lydia; Lourie, Rohan; Tong, Hui; Sheng, Yong H.; Wang, Ran; Kang, Alicia; Schreiber, Veronika; Wong, Kuan Yau; Magor, Graham; Denman, Stuart; Begun, Jakob; Florin, Timothy H.; Perkins, Andrew; Cuív, Páraic Ó.; McGuckin, Michael A.; Hasnain, Sumaira Z.

    2016-01-01

    Prolonged high fat diets (HFD) induce low-grade chronic intestinal inflammation in mice, and diets high in saturated fat are a risk factor for the development of human inflammatory bowel diseases. We hypothesized that HFD-induced endoplasmic reticulum (ER)/oxidative stress occur in intestinal secretory goblet cells, triggering inflammatory signaling and reducing synthesis/secretion of proteins that form the protective mucus barrier. In cultured intestinal cells non-esterified long-chain saturated fatty acids directly increased oxidative/ER stress leading to protein misfolding. A prolonged HFD elevated the intestinal inflammatory cytokine signature, alongside compromised mucosal barrier integrity with a decrease in goblet cell differentiation and Muc2, a loss in the tight junction protein, claudin-1 and increased serum endotoxin levels. In Winnie mice, that develop spontaneous colitis, HFD-feeding increased ER stress, further compromised the mucosal barrier and increased the severity of colitis. In obese mice IL-22 reduced ER/oxidative stress and improved the integrity of the mucosal barrier, and reversed microbial changes associated with obesity with an increase in Akkermansia muciniphila. Consistent with epidemiological studies, our experiments suggest that HFDs are likely to impair intestinal barrier function, particularly in early life, which partially involves direct effects of free-fatty acids on intestinal cells, and this can be reversed by IL-22 therapy. PMID:27350069

  1. 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.

  2. Supplementation of strontium to a chondrogenic medium promotes chondrogenic differentiation of human dedifferentiated fat cells.

    PubMed

    Okita, Naoya; Honda, Yoshitomo; Kishimoto, Naotaka; Liao, Wen; Azumi, Eiko; Hashimoto, Yoshiya; Matsumoto, Naoyuki

    2015-05-01

    Dedifferentiated fat cells (DFAT cells) isolated from adipose tissue have been demonstrated to differentiate into chondrogenic cells in vitro. Nevertheless, an efficient method to facilitate its chondrogenic differentiation is still unexplored, hampering the extensive application of these cells in cartilage regeneration therapies. Here we provide the evidence that supplementation of strontium ions (Sr) in a chondrogenic medium (CM) significantly promotes early chondrogenic differentiation of DFAT cells. Human DFAT cells and the mesenchymal stem cell line (RCB2153) were subjected to the CM supplemented with/without Sr. After 14 days, alcian blue staining intensity significantly increased in DFAT cells, but not in RCB2153, subjected to CM with Sr. mRNA expression analysis revealed that the CM with 1.5 mM Sr increased the expression of chondrogenic marker, collagen type 2 alpha 1, whereas there was no significant change in osteogenic markers, collagen type 1 alpha 1, runt-related transcription factor 2, and osteocalcin, and hypertrophic chondrogenic marker, collagen type 10 alpha 1. Inhibitors for extracellular signal-regulated kinase 1/2 (ERK1/2), Akt, and calcium-sensing receptor (CaSR) pathways significantly diminished the alcian blue staining intensity, providing the first evidence that these signal pathways are associated with chondrogenic differentiation of DFAT cells. CaSR and ERK1/2 pathways independently induced Sr-mediated early chondrogenic differentiation. These results suggest that Sr supplementation into the CM may provide a powerful platform for preparing chondrogenically differentiated DFAT cells for cartilage regeneration.

  3. High Fat Diet Inhibits Dendritic Cell and T Cell Response to Allergens but Does Not Impair Inhalational Respiratory Tolerance

    PubMed Central

    Pizzolla, Angela; Oh, Ding Yuan; Luong, Suzanne; Prickett, Sara R.; Henstridge, Darren C.; Febbraio, Mark A.; O’Hehir, Robyn E.; Rolland, Jennifer M.; Hardy, Charles L.

    2016-01-01

    The incidence of obesity has risen to epidemic proportions in recent decades, most commonly attributed to an increasingly sedentary lifestyle, and a ‘western’ diet high in fat and low in fibre. Although non-allergic asthma is a well-established co-morbidity of obesity, the influence of obesity on allergic asthma is still under debate. Allergic asthma is thought to result from impaired tolerance to airborne antigens, so-called respiratory tolerance. We sought to investigate whether a diet high in fats affects the development of respiratory tolerance. Mice fed a high fat diet (HFD) for 8 weeks showed weight gain, metabolic disease, and alteration in gut microbiota, metabolites and glucose metabolism compared to age-matched mice fed normal chow diet (ND). Respiratory tolerance was induced by repeated intranasal (i.n.) administration of ovalbumin (OVA), prior to induction of allergic airway inflammation (AAI) by sensitization with OVA in alum i.p. and subsequent i.n. OVA challenge. Surprisingly, respiratory tolerance was induced equally well in HFD and ND mice, as evidenced by decreased lung eosinophilia and serum OVA-specific IgE production. However, in a pilot study, HFD mice showed a tendency for impaired activation of airway dendritic cells and regulatory T cells compared with ND mice after induction of respiratory tolerance. Moreover, the capacity of lymph node cells to produce IL-5 and IL-13 after AAI was drastically diminished in HFD mice compared to ND mice. These results indicate that HFD does not affect the inflammatory or B cell response to an allergen, but inhibits priming of Th2 cells and possibly dendritic cell and regulatory T cell activation. PMID:27483441

  4. A Giant-Cell Lesion with Cellular Cannibalism in the Mandible: Case Report and Review of Brown Tumors in Hyperparathyroidism

    PubMed Central

    Cimetti, Laura; Annoni, Matteo; Anselmi, Diego; Tettamanti, Lucia; Tagliabue, Angelo

    2017-01-01

    A small radiolucent area in the mandible was discovered in a 58-year-old woman with no oral complaints. The patient's history included only hypertension. The lesion was considered as an inflammatory cyst and was enucleated. Three months later, a CT revealed the presence of a cyst-like lesion in the mandible with thin expanded buccal cortical plate, localized erosion, and a polylobate appearance on the lingual aspect of the cortical plate. The histological diagnosis of the lesion was central giant-cell granuloma (CGCG). The lesion was thoroughly enucleated. Nevertheless, another X-ray carried out six months later revealed multiple bilateral osteolytic areas throughout the jaw. In addition, widespread cortical plate erosion was observed, as well as signs of root resorption and periodontal enlargement. There was no sign of neurological involvement, although the nerves appeared to be dislocated. After full blood chemistry analysis and detailed collection of radiographs, the final diagnosis was brown tumors in primary hyperparathyroidism. This case report demonstrates how dental clinicians may be the first-line specialists who identify a complex systemic disease before other clinicians. Finally, it highlights the role of cellular cannibalism in predicting the clinical aggressiveness of brown tumors as well as in other giant-cell lesions. PMID:28280638

  5. A Giant-Cell Lesion with Cellular Cannibalism in the Mandible: Case Report and Review of Brown Tumors in Hyperparathyroidism.

    PubMed

    Azzi, Lorenzo; Cimetti, Laura; Annoni, Matteo; Anselmi, Diego; Tettamanti, Lucia; Tagliabue, Angelo

    2017-01-01

    A small radiolucent area in the mandible was discovered in a 58-year-old woman with no oral complaints. The patient's history included only hypertension. The lesion was considered as an inflammatory cyst and was enucleated. Three months later, a CT revealed the presence of a cyst-like lesion in the mandible with thin expanded buccal cortical plate, localized erosion, and a polylobate appearance on the lingual aspect of the cortical plate. The histological diagnosis of the lesion was central giant-cell granuloma (CGCG). The lesion was thoroughly enucleated. Nevertheless, another X-ray carried out six months later revealed multiple bilateral osteolytic areas throughout the jaw. In addition, widespread cortical plate erosion was observed, as well as signs of root resorption and periodontal enlargement. There was no sign of neurological involvement, although the nerves appeared to be dislocated. After full blood chemistry analysis and detailed collection of radiographs, the final diagnosis was brown tumors in primary hyperparathyroidism. This case report demonstrates how dental clinicians may be the first-line specialists who identify a complex systemic disease before other clinicians. Finally, it highlights the role of cellular cannibalism in predicting the clinical aggressiveness of brown tumors as well as in other giant-cell lesions.

  6. Combination therapy with catechins and caffeine inhibits fat accumulation in 3T3-L1 cells

    PubMed Central

    Zhu, Xiaojuan; Yang, Licong; Xu, Feng; Lin, Lezhen; Zheng, Guodong

    2017-01-01

    Catechins and caffeine, which are green tea components, have a slimming effect; however, the combinational effect of fat metabolism in 3T3-L1 cells remains unclear. In the present study, 3T3-L1 cells were treated with catechins and caffeine in combination, and it was found that combination therapy with catechins and caffeine markedly reduced intracellular fat accumulation, mRNA expression levels of peroxisome proliferator-activated receptor-γ and CCAAT/enhancer-binding protein α in the early stage of cell differentiation were significantly reduced, and mRNA expression of fatty acid synthetase(FAS) andglycerol-3-phosphate dehydrogenase protein expression levels of FAS were downregulated. Noradrenaline-induced lipolysis was enhanced by caffeine, which markedly increased the protein expression of adipose triglyceride lipase and hormone sensitive lipase. These results indicated that combination therapy with catechins and caffeine synergistically inhibited lipid accumulation by regulating the gene and protein expression levels of lipid metabolism-related enzymes. Therefore, catechins and caffeine combination therapy has potential as a functional food that may be used to prevent obesity and lifestyle-associated diseases. PMID:28352352

  7. Parental high-fat programming of offspring development, health and β-cells.

    PubMed

    Cerf, Marlon E

    2011-01-01

    Recent studies extend the concept of developmental and adaptive plasticity to include a paternal role in the programming of metabolic disease, including diabetes. Parents greatly influence the development and health of their offspring. Although genetic imprinting plays a major role in determining offspring health outcomes, non-genetic transmission is also a critical determinant. Programming by parental high-fat feeding has demonstrated adverse effects on β-cell development and function in offspring. However, maternal and paternal programming effects vary in their potency, with mothers holding the greater influence due to their direct involvement in offspring development and health. Maintenance of parental health pre-conception and during the early phases of offspring life is critical to improve health outcomes of offspring, with the benefit of positive effects on parental health. Preservation and protection of β-cells throughout offspring life, even before conception, is a strategy to enhance β-cell survival in offspring.

  8. The effects of calcium channel blocker benidipine and calmodulin antagonist W7 on GDP-binding capacity of brown adipose tissue in mice.

    PubMed

    Song, Yuh-Min; Lin, Pi-Yao; Chen, Ming-Der

    2009-03-01

    It has been suggested that increased dietary calcium intake can attenuate obesity. Calcium antagonists, such as benidipine, also have been shown to have an anti-obesity effect. However, the mechanism for calcium-related anti-obesity effect has not yet been established. A defective brown adipose tissue thermogenesis has been shown in obese rodents. This study was designed to examine the direct effects of calcium channel blocker benidipine and calmodulin antagonist W7 administration on the adaptive thermogenesis in brown adipose tissue taken from the genetically obese mice and their lean controls. The GDP binding to brown-fat cell mitochondria was used as a brown adipose tissue thermogenic index. The results show that benidipine treatment had no marked effect on brown-fat cell GDP-binding capacities in both obese and lean mice. However, GDP-binding capacities were significantly reduced in both obese and lean mice after the W7 administration. The results of this study support the previous finding that benidipine did not have direct thermogenic effect on brown adipose tissue and suggest that the change in intracellular calmodulin availability might contribute to the adaptive thermogenesis in brown adipose tissue.

  9. Efficient production of omega-3 fatty acid desaturase (sFat-1)-transgenic pigs by somatic cell nuclear transfer.

    PubMed

    Pan, DengKe; Zhang, Li; Zhou, YanRong; Feng, Chong; Long, Chuan; Liu, Xiao; Wan, Rong; Zhang, Jian; Lin, AiXing; Dong, EnQiu; Wang, ShuChen; Xu, HouGang; Chen, HongXing

    2010-04-01

    Omega-3(omega-3) fatty acid desaturase transgenic pigs may improve carcass fatty acid composition. The use of transgenic pigs is also an excellent large animal model for studying the role of omega-3 fatty acids in the prevention and treatment of coronary heart disease and cancer. Transgenic pigs carrying synthesized fatty acid desaturase-1 gene (sFat-1) from Caenorhabditis briggsae by somatic cell nuclear transfer (SCNT) were produced for the first time in China. Porcine fetal fibroblast cells were transfected with a sFat-1 expression cassette by the liposome-mediated method. Transgenic embryos were reconstructed by nuclear transfer of positive cells into enucleated in vitro matured oocytes. A total of 1889 reconstructed embryos were transferred into 10 naturally cycling gilts. Nine early pregnancies were established, 7 of which went to term. Twenty-one piglets were born. The cloning efficiency was 1.1% (born piglets/transferred embryos). The integration of the sFat-1 gene was confirmed in 15 live cloned piglets by PCR and Southern blot except for 2 piglets. Expression of the sFat-1 gene in 12 of 13 piglets was detected with RT-PCR. The data demonstrates that an efficient system for sFat-1 transgenic cloned pigs was developed, which led to the successful production of piglets expressing the sFat-1 gene.

  10. Adipocytes in both brown and white adipose tissue of adult mice are functionally connected via gap junctions: implications for Chagas disease

    PubMed Central

    Burke, Shoshana; Nagajyothi, Fnu; Thi, Mia M.; Hanani, Menachem; Scherer, Philipp E.; Tanowitz, Herbert B.; Spray, David C.

    2015-01-01

    Adipose tissue serves as a host reservoir for the protozoan Trypanosoma cruzi, the causative organism in Chagas disease. Gap junctions interconnect cells of most tissues, serving to synchronize cell activities including secretion in glandular tissue, and we have previously demonstrated that gap junctions are altered in various tissues and cells infected with T. cruzi. Herein, we examined the gap junction protein connexin 43 (Cx43) expression in infected adipose tissues. Adipose tissue is the largest endocrine organ of the body and is also involved in other physiological functions. In mammals, it is primarily composed of white adipocytes. Although gap junctions are a prominent feature of brown adipocytes, they have not been explored extensively in white adipocytes, especially in the setting of infection. Thus, we examined functional coupling in both white and brown adipocytes in mice. Injection of electrical current or the dye Lucifer Yellow into adipocytes within fat tissue spread to adjacent cells, which was reduced by treatment with agents known to block gap junctions. Moreover, Cx43 was detected in both brown and white fat tissue. At thirty and ninety days post-infection, Cx43 was downregulated in brown adipocytes and upregulated in white adipocytes. Gap junction-mediated intercellular communication likely contributes to hormone secretion and other functions in white adipose tissue and to nonshivering thermogenesis in brown fat, and modulation of the coupling by T. cruzi infection is expected to impact these functions. PMID:25150689

  11. Adipocytes in both brown and white adipose tissue of adult mice are functionally connected via gap junctions: implications for Chagas disease.

    PubMed

    Burke, Shoshana; Nagajyothi, Fnu; Thi, Mia M; Hanani, Menachem; Scherer, Philipp E; Tanowitz, Herbert B; Spray, David C

    2014-11-01

    Adipose tissue serves as a host reservoir for the protozoan Trypanosoma cruzi, the causative organism in Chagas disease. Gap junctions interconnect cells of most tissues, serving to synchronize cell activities including secretion in glandular tissue, and we have previously demonstrated that gap junctions are altered in various tissues and cells infected with T. cruzi. Herein, we examined the gap junction protein connexin 43 (Cx43) expression in infected adipose tissues. Adipose tissue is the largest endocrine organ of the body and is also involved in other physiological functions. In mammals, it is primarily composed of white adipocytes. Although gap junctions are a prominent feature of brown adipocytes, they have not been explored extensively in white adipocytes, especially in the setting of infection. Thus, we examined functional coupling in both white and brown adipocytes in mice. Injection of electrical current or the dye Lucifer Yellow into adipocytes within fat tissue spread to adjacent cells, which was reduced by treatment with agents known to block gap junctions. Moreover, Cx43 was detected in both brown and white fat tissue. At thirty and ninety days post-infection, Cx43 was downregulated in brown adipocytes and upregulated in white adipocytes. Gap junction-mediated intercellular communication likely contributes to hormone secretion and other functions in white adipose tissue and to nonshivering thermogenesis in brown fat, and modulation of the coupling by T. cruzi infection is expected to impact these functions.

  12. Cell mechanisms of gustatory lipids perception and modulation of the dietary fat preference.

    PubMed

    Dramane, Gado; Akpona, Simon; Besnard, Philippe; Khan, Naim A

    2014-12-01

    Dietary lipids are usually responsible of several metabolic disorders. Recent compelling evidences suggest that there is a sixth taste modality, destined for the detection of oro-gustatory fats. The lipid-binding glycoprotein CD36, expressed by circumvallate papillae (CVP) of the mouse tongue, has been shown to be implicated in oro-gustatory perception of dietary lipids. We demonstrate that linoleic acid (LA) by activating sPLA2, cPLA2 and iPLA2 via CD36, produced arachidonic acid (AA) and lyso-phosphatidylcholine (Lyso-PC) which triggered Ca(2+) influx in CD36-positive taste bud cells (TBC), purified from mouse CVP. LA induced the production of Ca(2+) influx factor (CIF). CIF, AA and Lyso-PC exerted different actions on the opening of store-operated Ca2+ (SOC) channels, constituted of Orai proteins and regulated by STIM1, a sensor of Ca(2+) depletion in the endoplasmic reticulum. We observed that CIF and Lyso-PC opened Orai1 channels whereas AA-opened Ca(2+) channels were composed of Orai1/Orai3. STIM1 was found to regulate LA-induced CIF production and opening of both kinds of Ca(2+) channels. Furthermore, Stim1(-/-) mice lost the spontaneous preference for fat, observed in wild-type animals. Our results suggest that fatty acid-induced Ca(2+) signaling, regulated by STIM1 via CD36, might be implicated in oro-gustatory perception of dietary lipids and the spontaneous preference for fat. Other cell types are involved in, and external factors can influence this preference.

  13. Co-culture with periodontal ligament stem cells enhances osteogenic gene expression in de-differentiated fat cells.

    PubMed

    Tansriratanawong, Kallapat; Tamaki, Yuichi; Ishikawa, Hiroshi; Sato, Soh

    2014-10-01

    In recent decades, de-differentiated fat cells (DFAT cells) have emerged in regenerative medicine because of their trans-differentiation capability and the fact that their characteristics are similar to bone marrow mesenchymal stem cells. Even so, there is no evidence to support the osteogenic induction using DFAT cells in periodontal regeneration and also the co-culture system. Consequently, this study sought to evaluate the DFAT cells co-culture with periodontal ligament stem cells (PDLSCs) in vitro in terms of gene expression by comparing runt-related transcription factor 2 (RUNX2) and Peroxisome proliferator-activated receptor gamma 2 (PPARγ2) genes. We isolated DFAT cells from mature adipocytes and compared proliferation with PDLSCs. After co-culture with PDLSCs, we analyzed transcriptional activity implying by DNA methylation in all adipogenic gene promoters using combined bisulfite restriction analysis. We compared gene expression in RUNX2 gene with the PPARγ2 gene using quantitative RT-PCR. After being sub-cultured, DFAT cells demonstrated morphology similar to fibroblast-like cells. At the same time, PDLSCs established all stem cell characteristics. Interestingly, the co-culture system attenuated proliferation while enhancing osteogenic gene expression in RUNX2 gene. Using the co-culture system, DFAT cells could trans-differentiate into osteogenic lineage enhancing, but conversely, their adipogenic characteristic diminished. Therefore, DFAT cells and the co-culture system might be a novel cell-based therapy for promoting osteogenic differentiation in periodontal regeneration.

  14. ELOVL3 is an important component for early onset of lipid recruitment in brown adipose tissue.

    PubMed

    Westerberg, Rolf; Månsson, Jan-Erik; Golozoubova, Valeria; Shabalina, Irina G; Backlund, Emma C; Tvrdik, Petr; Retterstøl, Kjetil; Capecchi, Mario R; Jacobsson, Anders

    2006-02-24

    During the recruitment process of brown adipose tissue, the mRNA level of the fatty acyl chain elongase Elovl3 is elevated more than 200-fold in cold-stressed mice. We have obtained Elovl3-ablated mice and report here that, although cold-acclimated Elovl3-ablated mice experienced an increased heat loss due to impaired skin barrier, they were unable to hyperrecruit their brown adipose tissue. Instead, they used muscle shivering in order to maintain body temperature. Lack of Elovl3 resulted in a transient decrease in the capacity to elongate saturated fatty acyl-CoAs into very long chain fatty acids, concomitantly with the occurrence of reduced levels of arachidic acid (C20:0) and behenic acid (C22:0) in brown adipose tissue during the initial cold stress. This effect on very long chain fatty acid synthesis could be illustrated as a decrease in the condensation activity of the elongation enzyme. In addition, warm-acclimated Elovl3-ablated mice showed diminished ability to accumulate fat and reduced metabolic capacity within the brown fat cells. This points to ELOVL3 as an important regulator of endogenous synthesis of saturated very long chain fatty acids and triglyceride formation in brown adipose tissue during the early phase of the tissue recruitment.

  15. RIP140 Represses the “Brown-in-White” Adipocyte Program Including a Futile Cycle of Triacyclglycerol Breakdown and Synthesis

    PubMed Central

    Kiskinis, Evangelos; Chatzeli, Lemonia; Curry, Edward; Kaforou, Myrsini; Frontini, Andrea; Cinti, Saverio; Montana, Giovanni; Parker, Malcolm G.

    2014-01-01

    Receptor-interacting protein 140 (RIP140) is a corepressor of nuclear receptors that is highly expressed in adipose tissues. We investigated the role of RIP140 in conditionally immortal preadipocyte cell lines prepared from white or brown fat depots. In white adipocytes, a large set of brown fat-associated genes was up-regulated in the absence of RIP140. In contrast, a relatively minor role can be ascribed to RIP140 in the control of basal gene expression in differentiated brown adipocytes because significant changes were observed only in Ptgds and Fabp3. The minor role of RIP140 in brown adipocytes correlates with the similar histology and uncoupling protein 1 and CIDEA staining in knockout compared with wild-type brown adipose tissue (BAT). In contrast, RIP140 knockout sc white adipose tissue (WAT) shows increased numbers of multilocular adipocytes with elevated staining for uncoupling protein 1 and CIDEA. Furthermore in a white adipocyte cell line, the markers of BRITE adipocytes, Tbx1, CD137, Tmem26, Cited1, and Epsti1 were repressed in the presence of RIP140 as was Prdm16. Microarray analysis of wild-type and RIP140-knockout white fat revealed elevated expression of genes associated with cold-induced expression or high expression in BAT. A set of genes associated with a futile cycle of triacylglycerol breakdown and resynthesis and functional assays revealed that glycerol kinase and glycerol-3-phosphate dehydrogenase activity as well as [3H]glycerol incorporation were elevated in the absence of RIP140. Thus, RIP140 blocks the BRITE program in WAT, preventing the expression of brown fat genes and inhibiting a triacylglycerol futile cycle, with important implications for energy homeostasis. PMID:24479876

  16. RIP140 represses the "brown-in-white" adipocyte program including a futile cycle of triacylglycerol breakdown and synthesis.

    PubMed

    Kiskinis, Evangelos; Chatzeli, Lemonia; Curry, Edward; Kaforou, Myrsini; Frontini, Andrea; Cinti, Saverio; Montana, Giovanni; Parker, Malcolm G; Christian, Mark

    2014-03-01

    Receptor-interacting protein 140 (RIP140) is a corepressor of nuclear receptors that is highly expressed in adipose tissues. We investigated the role of RIP140 in conditionally immortal preadipocyte cell lines prepared from white or brown fat depots. In white adipocytes, a large set of brown fat-associated genes was up-regulated in the absence of RIP140. In contrast, a relatively minor role can be ascribed to RIP140 in the control of basal gene expression in differentiated brown adipocytes because significant changes were observed only in Ptgds and Fabp3. The minor role of RIP140 in brown adipocytes correlates with the similar histology and uncoupling protein 1 and CIDEA staining in knockout compared with wild-type brown adipose tissue (BAT). In contrast, RIP140 knockout sc white adipose tissue (WAT) shows increased numbers of multilocular adipocytes with elevated staining for uncoupling protein 1 and CIDEA. Furthermore in a white adipocyte cell line, the markers of BRITE adipocytes, Tbx1, CD137, Tmem26, Cited1, and Epsti1 were repressed in the presence of RIP140 as was Prdm16. Microarray analysis of wild-type and RIP140-knockout white fat revealed elevated expression of genes associated with cold-induced expression or high expression in BAT. A set of genes associated with a futile cycle of triacylglycerol breakdown and resynthesis and functional assays revealed that glycerol kinase and glycerol-3-phosphate dehydrogenase activity as well as [(3)H]glycerol incorporation were elevated in the absence of RIP140. Thus, RIP140 blocks the BRITE program in WAT, preventing the expression of brown fat genes and inhibiting a triacylglycerol futile cycle, with important implications for energy homeostasis.

  17. Fat2 acts through the WAVE regulatory complex to drive collective cell migration during tissue rotation

    PubMed Central

    Squarr, Anna Julia; Brinkmann, Klaus; Chen, Baoyu; Steinbacher, Tim; Ebnet, Klaus; Rosen, Michael K.

    2016-01-01

    Directional cell movements during morphogenesis require the coordinated interplay between membrane receptors and the actin cytoskeleton. The WAVE regulatory complex (WRC) is a conserved actin regulator. Here, we found that the atypical cadherin Fat2 recruits the WRC to basal membranes of tricellular contacts where a new type of planar-polarized whip-like actin protrusion is formed. Loss of either Fat2 function or its interaction with the WRC disrupts tricellular protrusions and results in the formation of nonpolarized filopodia. We provide further evidence for a molecular network in which the receptor tyrosine phosphatase Dlar interacts with the WRC to couple the extracellular matrix, the membrane, and the actin cytoskeleton during egg elongation. Our data uncover a mechanism by which polarity information can be transduced from a membrane receptor to a key actin regulator to control collective follicle cell migration during egg elongation. 4D-live imaging of rotating MCF10A mammary acini further suggests an evolutionary conserved mechanism driving rotational motions in epithelial morphogenesis. PMID:26903538

  18. Seipin deficiency alters brown adipose tissue thermogenesis and insulin sensitivity in a non-cell autonomous mode

    PubMed Central

    Dollet, L.; Magré, J.; Joubert, M.; Le May, C.; Ayer, A.; Arnaud, L.; Pecqueur, C.; Blouin, V.; Cariou, B.; Prieur, X.

    2016-01-01

    Loss-of-function mutations in BSCL2 are responsible for Berardinelli-Seip congenital lipodystrophy, a rare disorder characterized by near absence of adipose tissue associated with insulin resistance. Seipin-deficient (Bscl2−/−) mice display an almost total loss of white adipose tissue (WAT) with residual brown adipose tissue (BAT). Previous cellular studies have shown that seipin deficiency alters white adipocyte differentiation. In this study, we aimed to decipher the consequences of seipin deficiency in BAT. Using a brown adipocyte cell-line, we show that seipin knockdown had very little effect on adipocyte differentiation without affecting insulin sensitivity and oxygen consumption. However, when submitted to cold acclimation or chronic β3 agonist treatment, Bscl2−/− mice displayed altered thermogenic capacity, despite several signs of BAT remodeling. Under cold activation, Bscl2−/− mice were able to maintain their body temperature when fed ad libitum, but not under short fasting. At control temperature (i.e. 21 °C), fasting worsened Bscl2−/− BAT properties. Finally, Bscl2−/− BAT displayed obvious signs of insulin resistance. Our results in these lipodystrophic mice strongly suggest that BAT activity relies on WAT as an energetic substrate provider and adipokine-producing organ. Therefore, the WAT/BAT dialogue is a key component of BAT integrity in guaranteeing its response to insulin and cold-activated adrenergic signals. PMID:27748422

  19. Impact of baseline visceral fat accumulation on prognosis in patients with metastatic renal cell carcinoma treated with systemic therapy.

    PubMed

    Mizuno, Ryuichi; Miyajima, Akira; Hibi, Taizo; Masuda, Aya; Shinojima, Toshiaki; Kikuchi, Eiji; Jinzaki, Masahiro; Oya, Mototsugu

    2017-04-01

    The aim of this study was to evaluate the clinical significance of visceral fat accumulation as a prognostic factor in patients with metastatic renal cell carcinoma (mRCC) treated with systemic therapies. A total of 114 patients were retrospectively reviewed. All patients received systemic therapy for mRCC at Keio University hospital in Japan. The intra-abdominal visceral fat area was determined by computed tomography at the umbilical level. The visceral fat accumulation was defined as ≥100 cm(2). The mean visceral fat area was 107.4 ± 62.8 cm(2). In the whole cohort, the median follow-up was 29 months. According to the Memorial Sloan Kettering Cancer Center (MSKCC) classification, 27.2% patients were favorable risk, 53.5% were intermediate risk, and 19.3% were poor risk. Visceral fat accumulation correlated with improved progression-free (P = 0.0070) and overall survival (P = 0.0001). On multivariate analysis, visceral fat accumulation (P = 0.0290) and MSKCC classification (P = 0.0085) were independent indices to predict progression-free survival in first-line treatment. In addition, visceral fat accumulation (P = 0.0007) and MSKCC classification (P = 0.0005) independently predicted overall survival. Prognostic grouping using visceral fat accumulation was identified as an independent prognostic marker in patients with mRCC. The addition of visceral fat accumulation improved the prognostic value of MSKCC classification alone in predicting overall survival in patients treated with systemic therapy for mRCC.

  20. Enhancement of early cardiac differentiation of dedifferentiated fat cells by dimethyloxalylglycine via notch signaling pathway

    PubMed Central

    Li, Fuhai; Li, Zongzhuang; Jiang, Zhi; Tian, Ye; Wang, Zhi; Yi, Wei; Zhang, Chenyun

    2016-01-01

    Background: Hypoxia has been reported to possess the ability to induce mature lipid-filled adipocytes to differentiate into fibroblast-like multipotent dedifferentiated fat (DFAT) cells and stem cells such as iPSCs (interstitial pluripotent stem cells) and ESCs (embryonic stem cells) and then to differentiate into cardiomyocytes. However, the effect of hypoxia on cardiac differentiation of DFAT cells and its underlying molecular mechanism remains to be investigated. Objective: To investigate the role of hypoxia in early cardiac differentiation of DFAT cells and the underlying molecular mechanism. Methods: DFAT cells were prepared from 4 to 6 week-age mice and cultured under hypoxic conditions by adding Prolyl hydroxylase inhibitor and dimethyloxalylglycine (DMOG) into the culture media. To inhibit or block Notch signaling, γ-secretase inhibitor-II (GSI-II) and Notch1 siRNA (si-Notch1) were used. DFAT cell viability was detected using MTT assay. qRT-PCR, immunofluorescence microscopy and western blotting were used to evaluate the cardiac differentiation of DFAT cells and co-immunoprecipitation was used to study the interaction between HIF-1α and Notch signaling. Results: 0.6-mM DMOG failed to affect the viability of DFAT cells, but stimulated the cells to express early cardiac transcription factors including Islet1, Nkx2.5 and Gata4 in a time-dependent manner and increase the number of cTnT+ cardiomyocytes (detected at the 28th day after stimulation). It was also demonstrated that DMOG was involved in HIF-1α and Notch signaling as well as HIF-1α-NICD complex formation. Conclusion: Hypoxia enhanced early cardiac differentiation of DFAT cells through HIF-1α and Notch signaling pathway. PMID:27904680

  1. Enhancement of early cardiac differentiation of dedifferentiated fat cells by dimethyloxalylglycine via notch signaling pathway.

    PubMed

    Li, Fuhai; Li, Zongzhuang; Jiang, Zhi; Tian, Ye; Wang, Zhi; Yi, Wei; Zhang, Chenyun

    2016-01-01

    Background: Hypoxia has been reported to possess the ability to induce mature lipid-filled adipocytes to differentiate into fibroblast-like multipotent dedifferentiated fat (DFAT) cells and stem cells such as iPSCs (interstitial pluripotent stem cells) and ESCs (embryonic stem cells) and then to differentiate into cardiomyocytes. However, the effect of hypoxia on cardiac differentiation of DFAT cells and its underlying molecular mechanism remains to be investigated. Objective: To investigate the role of hypoxia in early cardiac differentiation of DFAT cells and the underlying molecular mechanism. Methods: DFAT cells were prepared from 4 to 6 week-age mice and cultured under hypoxic conditions by adding Prolyl hydroxylase inhibitor and dimethyloxalylglycine (DMOG) into the culture media. To inhibit or block Notch signaling, γ-secretase inhibitor-II (GSI-II) and Notch1 siRNA (si-Notch1) were used. DFAT cell viability was detected using MTT assay. qRT-PCR, immunofluorescence microscopy and western blotting were used to evaluate the cardiac differentiation of DFAT cells and co-immunoprecipitation was used to study the interaction between HIF-1α and Notch signaling. Results: 0.6-mM DMOG failed to affect the viability of DFAT cells, but stimulated the cells to express early cardiac transcription factors including Islet1, Nkx2.5 and Gata4 in a time-dependent manner and increase the number of cTnT(+) cardiomyocytes (detected at the 28(th) day after stimulation). It was also demonstrated that DMOG was involved in HIF-1α and Notch signaling as well as HIF-1α-NICD complex formation. Conclusion: Hypoxia enhanced early cardiac differentiation of DFAT cells through HIF-1α and Notch signaling pathway.

  2. High fat diet impairs the function of glucagon-like peptide-1 producing L-cells

    PubMed Central

    Richards, Paul; Pais, Ramona; Habib, Abdella M.; Brighton, Cheryl A.; Yeo, Giles S.H.; Reimann, Frank; Gribble, Fiona M.

    2016-01-01

    Glucagon-like peptide-1 (GLP-1) acts as a satiety signal and enhances insulin release. This study examined how GLP-1 production from intestinal L-cells is modified by dietary changes. Methods Transgenic mouse models were utilized in which L-cells could be purified by cell specific expression of a yellow fluorescent protein, Venus. Mice were fed on chow or 60% high fat diet (HFD) for 2 or 16 weeks. L-cells were purified by flow cytometry and analysed by microarray and quantitative RT-PCR. Enteroendocrine cell populations were examined by FACS analysis, and GLP-1 secretion was assessed in primary intestinal cultures. Results Two weeks HFD reduced the numbers of GLP-1 positive cells in the colon, and of GIP positive cells in the small intestine. Purified small intestinal L-cells showed major shifts in their gene expression profiles. In mice on HFD for 16 weeks, significant reductions were observed in the expression of L-cell specific genes, including those encoding gut hormones (Gip, Cck, Sct, Nts), prohormone processing enzymes (Pcsk1, Cpe), granins (Chgb, Scg2), nutrient sensing machinery (Slc5a1, Slc15a1, Abcc8, Gpr120) and enteroendocrine-specific transcription factors (Etv1, Isl1, Mlxipl, Nkx2.2 and Rfx6). A corresponding reduction in the GLP-1 secretory responsiveness to nutrient stimuli was observed in primary small intestinal cultures. Conclusion Mice fed on HFD exhibited reduced expression in L-cells of many L-cell specific genes, suggesting an impairment of enteroendocrine cell function. Our results suggest that a western style diet may detrimentally affect the secretion of gut hormones and normal post-prandial signaling, which could impact on insulin secretion and satiety. PMID:26145551

  3. FatJ acts via the Hippo mediator Yap1 to restrict the size of neural progenitor cell pools

    PubMed Central

    Van Hateren, Nick J.; Das, Raman M.; Hautbergue, Guillaume M.; Borycki, Anne-Gaëlle; Placzek, Marysia; Wilson, Stuart A.

    2011-01-01

    The size, composition and functioning of the spinal cord is likely to depend on appropriate numbers of progenitor and differentiated cells of a particular class, but little is known about how cell numbers are controlled in specific cell cohorts along the dorsoventral axis of the neural tube. Here, we show that FatJ cadherin, identified in a large-scale RNA interference (RNAi) screen of cadherin genes expressed in the neural tube, is localised to progenitors in intermediate regions of the neural tube. Loss of function of FatJ promotes an increase in dp4-vp1 progenitors and a concomitant increase in differentiated Lim1+/Lim2+ neurons. Our studies reveal that FatJ mediates its action via the Hippo pathway mediator Yap1: loss of downstream Hippo components can rescue the defect caused by loss of FatJ. Together, our data demonstrate that RNAi screens are feasible in the chick embryonic neural tube, and show that FatJ acts through the Hippo pathway to regulate cell numbers in specific subsets of neural progenitor pools and their differentiated progeny. PMID:21521736

  4. Unmaking Brown

    ERIC Educational Resources Information Center

    Lockette, Tim

    2010-01-01

    America's schools are more segregated now than they were in the late 1960s. More than 50 years after "Brown v. Board of Education," educators need to radically rethink the meaning of "school choice." For decades at Wake County, buses would pick up public school students in largely minority communities along the Raleigh…

  5. Brown seaweed pigment as a dye source for photoelectrochemical solar cells

    NASA Astrophysics Data System (ADS)

    Calogero, Giuseppe; Citro, Ilaria; Di Marco, Gaetano; Armeli Minicante, Simona; Morabito, Marina; Genovese, Giuseppa

    2014-01-01

    Chlorophylls based-dyes obtained from seaweeds represent attractive alternatives to the expensive and polluting pyridil based Ru complexes because of their abundance in nature. Another important characteristic is that the algae do not subtract either cropland or agricultural water, therefore do not conflict with agro-food sector. This pigment shows a typical intense absorption in the UV/blue (Soret band) and a less intense band in the red/near IR (Q band) spectral regions and for these reasons appear very promising as sensitizer dyes for DSSC. In the present study, we utilized chlorophylls from samples of the brown alga Undaria pinnatifida as sensitizer in DSSCs. The dye, extracted by frozen seaweeds and used without any chemical purification, showed a very good fill factor (0.69). Even the photelectrochemical parameters if compared with the existent literature are very interesting.

  6. Mucous cell responses in gill and skin of brown trout Salmo trutta fario in acidic, aluminium-containing stream water.

    PubMed

    Ledy, K; Giambérini, L; Pihan, J C

    2003-10-24

    Morphometric examination was carried out on the gills and skin of wild and caged hatchery brown trout Salmo trutta fario in an acidic (pH 4.9 to 5.4; Al 203 to 250 microg l(-1)) and in a non-acidic (pH 6.7 to 7.0; Al 27 to 67 microg l(-1)) stream in the Vosges Mountains (NE France) to assess the sublethal effects of acidic water on the mucous cell response. The caged fish were randomly collected after 2, 4, 7 and 11 d and the wild fish were obtained by electrofishing. After 2 d, a reduction of both mucous cell (MC) number and size was observed in the gills of fish held in the acidic stream, suggesting a massive mucus discharge. Hyperplasia and hypertrophy of cells immediately followed this mucus secretion. In the same fish population, skin examination showed a slight and delayed decrease of MC number but a significant increase of cell size. The number of mucous cells of gills and skin was similar in both wild trout populations, whereas a significant MC hypertrophy was observed in the wild fish of the acidic stream. The present field experiment indicates that caged fish could be useful as early indicators of acidification. In addition, the examination of wild populations suggested the occurrence of adaptive mechanisms, information that might be of importance in the context of river recovery programs.

  7. L-Arginine promotes protein synthesis and cell growth in brown adipocyte precursor cells via the mTOR signal pathway.

    PubMed

    Ma, Xi; Han, Meng; Li, Defa; Hu, Shengdi; Gilbreath, Kyler R; Bazer, Fuller W; Wu, Guoyao

    2017-03-04

    L-Arginine has been reported to enhance brown adipose tissue developments in fetal lambs of obese ewes, but the underlying mechanism is unknown. The present study tested the hypothesis that L-arginine stimulates growth and development of brown adipocyte precursor cells (BAPCs) through activation of mammalian target of rapamycin cell signaling. BAPCs isolated from fetal lambs at day 90 of gestation were incubated   for 6 h in arginine-free DMEM, and then cultured in DMEM with concentrations of 50, 100, 200, 500 or 1000 μmol L-arginine/L for 24-96 h. Cell proliferation, protein turnover, the mammalian target of rapamycin (mTOR) signaling pathway and pre-adipocyte differentiation markers were determined. L-arginine treatment enhanced (P < 0.05) BAPC growth and protein synthesis, while inhibiting proteolysis in a dose-dependent manner. Compared with 50 and 100 μmol/L (the concentrations of arginine in the maternal plasma of obese ewes), 200 μmol L-arginine/L (the concentrations of arginine in the maternal plasma of obese ewes receiving arginine supplementation) increased (P < 0.05) the abundances of phosphorylated mTOR, P70(S6K) and 4EBP1, as well as the abundances of PGC1α, UCP1, BMP7 and PRDM16. These novel findings indicate that increasing extra-cellular arginine concentration from 50 to 200 µmol/L activates mTOR cell signaling in BAPCs and enhances their growth and development in a dose-dependent manner. Our results provide a mechanism for arginine supplementation to enhance the development of brown adipose tissue in fetal lambs.

  8. Use of Rat Mature Adipocyte-Derived Dedifferentiated Fat Cells as a Cell Source for Periodontal Tissue Regeneration

    PubMed Central

    Akita, Daisuke; Kano, Koichiro; Saito-Tamura, Yoko; Mashimo, Takayuki; Sato-Shionome, Momoko; Tsurumachi, Niina; Yamanaka, Katsuyuki; Kaneko, Tadashi; Toriumi, Taku; Arai, Yoshinori; Tsukimura, Naoki; Matsumoto, Taro; Ishigami, Tomohiko; Isokawa, Keitaro; Honda, Masaki

    2016-01-01

    Lipid-free fibroblast-like cells, known as dedifferentiated fat (DFAT) cells, can be generated from mature adipocytes with a large single lipid droplet. DFAT cells can re-establish their active proliferation ability and can transdifferentiate into various cell types under appropriate culture conditions. The first objective of this study was to compare the multilineage differentiation potential of DFAT cells with that of adipose-derived stem cells (ASCs) on mesenchymal stem cells. We obtained DFAT cells and ASCs from inbred rats and found that rat DFAT cells possess higher osteogenic differentiation potential than rat ASCs. On the other hand, DFAT cells show similar adipogenic differentiation, and chondrogenic differentiation potential in comparison with ASCs. The second objective of this study was to assess the regenerative potential of DFAT cells combined with novel solid scaffolds composed of PLGA (Poly d, l-lactic-co-glycolic acid) on periodontal tissue, and to compare this with the regenerative potential of ASCs combined with PLGA scaffolds. Cultured DFAT cells and ASCs were seeded onto PLGA scaffolds (DFAT/PLGA and ASCs/PLGA) and transplanted into periodontal fenestration defects in rat mandible. Micro computed tomography analysis revealed a significantly higher amount of bone regeneration in the DFAT/PLGA group compared with that of ASCs/PLGA and PLGA-alone groups at 2, 3, and 5 weeks after transplantation. Similarly, histomorphometric analysis showed that DFAT/PLGA groups had significantly greater width of cementum, periodontal ligament and alveolar bone than ASCs/PLGA and PLGA-alone groups. In addition, transplanted fluorescent-labeled DFAT cells were observed in the periodontal ligament beside the newly formed bone and cementum. These findings suggest that DFAT cells have a greater potential for enhancing periodontal tissue regeneration than ASCs. Therefore, DFAT cells are a promising cell source for periodontium regeneration. PMID:26941649

  9. Use of Rat Mature Adipocyte-Derived Dedifferentiated Fat Cells as a Cell Source for Periodontal Tissue Regeneration.

    PubMed

    Akita, Daisuke; Kano, Koichiro; Saito-Tamura, Yoko; Mashimo, Takayuki; Sato-Shionome, Momoko; Tsurumachi, Niina; Yamanaka, Katsuyuki; Kaneko, Tadashi; Toriumi, Taku; Arai, Yoshinori; Tsukimura, Naoki; Matsumoto, Taro; Ishigami, Tomohiko; Isokawa, Keitaro; Honda, Masaki

    2016-01-01

    Lipid-free fibroblast-like cells, known as dedifferentiated fat (DFAT) cells, can be generated from mature adipocytes with a large single lipid droplet. DFAT cells can re-establish their active proliferation ability and can transdifferentiate into various cell types under appropriate culture conditions. The first objective of this study was to compare the multilineage differentiation potential of DFAT cells with that of adipose-derived stem cells (ASCs) on mesenchymal stem cells. We obtained DFAT cells and ASCs from inbred rats and found that rat DFAT cells possess higher osteogenic differentiation potential than rat ASCs. On the other hand, DFAT cells show similar adipogenic differentiation, and chondrogenic differentiation potential in comparison with ASCs. The second objective of this study was to assess the regenerative potential of DFAT cells combined with novel solid scaffolds composed of PLGA (Poly d, l-lactic-co-glycolic acid) on periodontal tissue, and to compare this with the regenerative potential of ASCs combined with PLGA scaffolds. Cultured DFAT cells and ASCs were seeded onto PLGA scaffolds (DFAT/PLGA and ASCs/PLGA) and transplanted into periodontal fenestration defects in rat mandible. Micro computed tomography analysis revealed a significantly higher amount of bone regeneration in the DFAT/PLGA group compared with that of ASCs/PLGA and PLGA-alone groups at 2, 3, and 5 weeks after transplantation. Similarly, histomorphometric analysis showed that DFAT/PLGA groups had significantly greater width of cementum, periodontal ligament and alveolar bone than ASCs/PLGA and PLGA-alone groups. In addition, transplanted fluorescent-labeled DFAT cells were observed in the periodontal ligament beside the newly formed bone and cementum. These findings suggest that DFAT cells have a greater potential for enhancing periodontal tissue regeneration than ASCs. Therefore, DFAT cells are a promising cell source for periodontium regeneration.

  10. Milk fat globule-EGF factor 8 mediates the enhancement of apoptotic cell clearance by glucocorticoids

    PubMed Central

    Lauber, K; Keppeler, H; Munoz, L E; Koppe, U; Schröder, K; Yamaguchi, H; Krönke, G; Uderhardt, S; Wesselborg, S; Belka, C; Nagata, S; Herrmann, M

    2013-01-01

    The phagocytic clearance of apoptotic cells is essential to prevent chronic inflammation and autoimmunity. The phosphatidylserine-binding protein milk fat globule-EGF factor 8 (MFG-E8) is a major opsonin for apoptotic cells, and MFG-E8−/− mice spontaneously develop a lupus-like disease. Similar to human systemic lupus erythematosus (SLE), the murine disease is associated with an impaired clearance of apoptotic cells. SLE is routinely treated with glucocorticoids (GCs), whose anti-inflammatory effects are consentaneously attributed to the transrepression of pro-inflammatory cytokines. Here, we show that the GC-mediated transactivation of MFG-E8 expression and the concomitantly enhanced elimination of apoptotic cells constitute a novel aspect in this context. Patients with chronic inflammation receiving high-dose prednisone therapy displayed substantially increased MFG-E8 mRNA levels in circulating monocytes. MFG-E8 induction was dependent on the GC receptor and several GC response elements within the MFG-E8 promoter. Most intriguingly, the inhibition of MFG-E8 induction by RNA interference or genetic knockout strongly reduced or completely abolished the phagocytosis-enhancing effect of GCs in vitro and in vivo. Thus, MFG-E8-dependent promotion of apoptotic cell clearance is a novel anti-inflammatory facet of GC treatment and renders MFG-E8 a prospective target for future therapeutic interventions in SLE. PMID:23832117

  11. Milk fat globule-EGF factor 8 mediates the enhancement of apoptotic cell clearance by glucocorticoids.

    PubMed

    Lauber, K; Keppeler, H; Munoz, L E; Koppe, U; Schröder, K; Yamaguchi, H; Krönke, G; Uderhardt, S; Wesselborg, S; Belka, C; Nagata, S; Herrmann, M

    2013-09-01

    The phagocytic clearance of apoptotic cells is essential to prevent chronic inflammation and autoimmunity. The phosphatidylserine-binding protein milk fat globule-EGF factor 8 (MFG-E8) is a major opsonin for apoptotic cells, and MFG-E8(-/-) mice spontaneously develop a lupus-like disease. Similar to human systemic lupus erythematosus (SLE), the murine disease is associated with an impaired clearance of apoptotic cells. SLE is routinely treated with glucocorticoids (GCs), whose anti-inflammatory effects are consentaneously attributed to the transrepression of pro-inflammatory cytokines. Here, we show that the GC-mediated transactivation of MFG-E8 expression and the concomitantly enhanced elimination of apoptotic cells constitute a novel aspect in this context. Patients with chronic inflammation receiving high-dose prednisone therapy displayed substantially increased MFG-E8 mRNA levels in circulating monocytes. MFG-E8 induction was dependent on the GC receptor and several GC response elements within the MFG-E8 promoter. Most intriguingly, the inhibition of MFG-E8 induction by RNA interference or genetic knockout strongly reduced or completely abolished the phagocytosis-enhancing effect of GCs in vitro and in vivo. Thus, MFG-E8-dependent promotion of apoptotic cell clearance is a novel anti-inflammatory facet of GC treatment and renders MFG-E8 a prospective target for future therapeutic interventions in SLE.

  12. High fat programming of beta cell compensation, exhaustion, death and dysfunction.

    PubMed

    Cerf, Marlon E

    2015-03-01

    Programming refers to events during critical developmental windows that shape progeny health outcomes. Fetal programming refers to the effects of intrauterine (in utero) events. Lactational programming refers to the effects of events during suckling (weaning). Developmental programming refers to the effects of events during both fetal and lactational life. Postnatal programming refers to the effects of events either from birth (lactational life) to adolescence or from weaning (end of lactation) to adolescence. Islets are most plastic during the early life course; hence programming during fetal and lactational life is most potent. High fat (HF) programming is the maintenance on a HF diet (HFD) during critical developmental life stages that alters progeny metabolism and physiology. HF programming induces variable diabetogenic phenotypes dependent on the timing and duration of the dietary insult. Maternal obesity reinforces HF programming effects in progeny. HF programming, through acute hyperglycemia, initiates beta cell compensation. However, HF programming eventually leads to chronic hyperglycemia that triggers beta cell exhaustion, death and dysfunction. In HF programming, beta cell dysfunction often co-presents with insulin resistance. Balanced, healthy nutrition during developmental windows is critical for preserving beta cell structure and function. Thus early positive nutritional interventions that coincide with the development of beta cells may reduce the overwhelming burden of diabetes and metabolic disease.

  13. MiR130b-Regulation of PPARγ Coactivator- 1α Suppresses Fat Metabolism in Goat Mammary Epithelial Cells

    PubMed Central

    Chen, Zhi; Luo, Jun; Ma, LiuAn; Wang, Hui; Cao, WenTing; Xu, HuiFei; Zhu, JiangJiang; Sun, YuTing; Li, Jun; Yao, DaWei; Kang, Kang; Gou, Deming

    2015-01-01

    Fat metabolism is a complicated process regulated by a series of factors. microRNAs (miRNAs) are a class of negative regulator of proteins and play crucial roles in many biological processes; including fat metabolism. Although there have been some researches indicating that miRNAs could influence the milk fat metabolism through targeting some factors, little is known about the effect of miRNAs on goat milk fat metabolism. Here we utilized an improved miRNA detection assay, S-Poly-(T), to profile the expression of miRNAs in the goat mammary gland in different periods, and found that miR-130b was abundantly and differentially expressed in goat mammary gland. Additionally, overexpressing miR-130b impaired adipogenesis while inhibiting miR-130b enhanced adipogenesis in goat mammary epithelial cells. Utilizing 3’-UTR assay and Western Blot analusis, the protein peroxisome proliferator-activated receptor coactivator-1α (PGC1α), a major regulator of fat metabolism, was demonstrated to be a potential target of miR-130b. Interestingly, miR-130b potently repressed PGC1α expression by targeting both the PGC1α mRNA coding and 3’ untranslated regions. These findings have some insight of miR-130b in mediating adipocyte differentiation by repressing PGC1α expression and this contributes to further understanding about the functional significance of miRNAs in milk fat synthesis. PMID:26579707

  14. Identification of an anticancer compound against HT-29 cells from Phellinus linteus grown on germinated brown rice

    PubMed Central

    Jeon, Tae-Il; Jung, Chang-Hwa; Cho, Jeong-Yong; Park, Dong Ki; Moon, Jae-Hak

    2013-01-01

    Objective To isolate and identify the anticancer compound against proliferation of human colon cancer cells from ethyl acetate (EtOAC) extract of Phellinus linteus grown on germinated brown rice (PB). Methods EtOAC extract of PB was partitioned with n-hexane, EtOAC, and water-saturated n-butanol. Anticancer compound of n-hexane layer was isolated and identified by HPLC and NMR, respectively. Cytotoxicity against HT-29 cells was tested by SRB assay. Results The n-hexane layer obtained after solvent fractionation of PB EtOAC extracts showed a potent anticancer activity against the HT-29 cell line. Atractylenolide I, a eudesmane-type sesquiterpene lactone, a major anticancer substance of PB, was isolated from the n-hexane layer by silica gel column chromatography and preparative-HPLC. This structure was elucidated by one- and two-dimensional NMR spectroscopic data. Atractylenolide I has not been reported in mushrooms or rice as of yet. The isolated compound dose-dependently inhibited the growth of HT-29 human colon cancer cells. Conclusions Atractylenolide I might contribute to the anticancer effect of PB. PMID:24075343

  15. Molecular pathways linking non-shivering thermogenesis and obesity: focusing on brown adipose tissue development.

    PubMed

    Valente, Angelica; Jamurtas, Athanasios Z; Koutedakis, Yiannis; Flouris, Andreas D

    2015-02-01

    An increase in energy intake and/or a decrease in energy expenditure lead to fat storage, causing overweight and obesity phenotypes. The objective of this review was to analyse, for the first time using a systematic approach, all published evidence from the past 8 years regarding the molecular pathways linking non-shivering thermogenesis and obesity in mammals, focusing on mechanisms involved in brown adipose tissue development. Two major databases were scanned from 2006 to 2013 using 'brown adipose tissue' AND 'uncoupling protein-1' AND 'mammalian thermoregulation' AND 'obesity' as key words. A total of 61 articles were retrieved using the search criteria. The available research used knockout methodologies, various substances, molecules and agonist treatments, or different temperature and diet conditions, to assess the molecular pathways linking non-shivering thermogenesis and obesity. By integrating the results of the evaluated animal and human studies, our analysis identified specific molecules that enhance non-shivering thermogenesis and metabolism by: (i) stimulating 'brite' (brown-like) cell development in white adipose tissue; (ii) increasing uncoupling protein-1 expression in brite adipocytes; and (iii) augmenting brown and/or brite adipose tissue mass. The latter can be also increased through low temperature, hibernation and/or molecules involved in brown adipocyte differentiation. Cold stimuli and/or certain molecules activate uncoupling protein-1 in the existing brown adipocytes, thus increasing total energy expenditure by a magnitude proportional to the number of available brown adipocytes. Future research should address the interplay between body mass, brown adipose tissue mass, as well as the main molecules involved in brite cell development.

  16. Obesity induced by a high-fat diet is associated with increased immune cell entry into the central nervous system.

    PubMed

    Buckman, Laura B; Hasty, Alyssa H; Flaherty, David K; Buckman, Christopher T; Thompson, Misty M; Matlock, Brittany K; Weller, Kevin; Ellacott, Kate L J

    2014-01-01

    Obesity is associated with chronic low-grade inflammation in peripheral tissues caused, in part, by the recruitment of inflammatory monocytes into adipose tissue. Studies in rodent models have also shown increased inflammation in the central nervous system (CNS) during obesity. The goal of this study was to determine whether obesity is associated with recruitment of peripheral immune cells into the CNS. To do this we used a bone marrow chimerism model to track the entry of green-fluorescent protein (GFP) labeled peripheral immune cells into the CNS. Flow cytometry was used to quantify the number of GFP(+) immune cells recruited into the CNS of mice fed a high-fat diet compared to standard chow fed controls. High-fat feeding resulted in obesity associated with a 30% increase in the number of GFP(+) cells in the CNS compared to control mice. Greater than 80% of the GFP(+) cells recruited to the CNS were also CD45(+) CD11b(+) indicating that the GFP(+) cells displayed characteristics of microglia/macrophages. Immunohistochemistry further confirmed the increase in GFP(+) cells in the CNS of the high-fat fed group and also indicated that 93% of the recruited cells were found in the parenchyma and had a stellate morphology. These findings indicate that peripheral immune cells can be recruited to the CNS in obesity and may contribute to the inflammatory response.

  17. Involvement of T helper 17 cells in D-penicillamine-induced autoimmune disease in Brown Norway rats.

    PubMed

    Zhu, Xu; Li, Jinze; Liu, Feng; Uetrecht, Jack P

    2011-04-01

    Idiosyncratic drug reactions (IDRs) are poorly understood, but their clinical characteristics suggest that they are immune mediated. Penicillamine-induced autoimmunity in Brown Norway rats has been utilized as an animal model for mechanistic studies of one type of IDR because it closely mimics the autoimmune syndromes that it causes in humans. Our previous work suggested that it is T-cell mediated. It has been shown that T helper 17 (Th17) cells play a central role in many types of autoimmune diseases. This study was designed to test whether Th17 cells are involved in the pathogenesis of penicillamine-induced autoimmunity and to establish an overall serum cytokine/chemokine profile for this IDR. In total, 24 serum cytokines/chemokines were determined and revealed a dynamic process. In sick animals, interleukin (IL) 6 and transforming growth factor-β1, known to be driving forces of Th17 differentiation, were consistently increased at both early and late stages of penicillamine treatment; however, no significant changes in these cytokines were observed in animals that did not develop autoimmunity. IL-17, a characteristic cytokine produced by Th17 cells, was increased in sick animals at both the messenger RNA and serum protein level. In addition, serum concentrations of IL-22, another characteristic cytokine produced by Th17 cells, were found to be elevated. Furthermore, the percentage of IL-17-producing CD4 T cells was significantly increased but only in sick animals. These data strongly suggest that Th17 cells are involved in penicillamine-induced autoimmunity. Such data provide important mechanistic clues that may help to predict which drug candidates will cause a relatively high incidence of such autoimmune IDRs.

  18. Drug ligand-induced activation of translocator protein (TSPO) stimulates steroid production by aged brown Norway rat Leydig cells.

    PubMed

    Chung, J Y; Chen, H; Midzak, A; Burnett, A L; Papadopoulos, V; Zirkin, B R

    2013-06-01

    Translocator protein (TSPO; 18 kDA) is a high-affinity cholesterol-binding protein that is integrally involved in cholesterol transfer from intracellular stores into mitochondria, the rate-determining step in steroid formation. Previous studies have shown that TSPO drug ligands are able to activate steroid production by MA-10 mouse Leydig tumor cells and by mitochondria isolated from steroidogenic cells. We hypothesized herein that the direct, pharmacological activation of TSPO might induce aged Leydig cells, which are characterized by reduced T production, to produce significantly higher levels of T both in vitro and in vivo. To test this, we first examined the in vitro effects of the TSPO selective and structurally distinct drug ligands N,N-dihexyl-2-(4-fluorophenyl)indole-3-acetamide (FGIN-1-27) and benzodiazepine 4'-chlorodiazepam (Ro5-4864) on steroidogenesis by Leydig cells isolated from aged (21-24 months old) and young adult (3-6 months old) Brown Norway rats. The ligands stimulated Leydig cell T production significantly, and equivalently, in cells of both ages, an effect that was significantly inhibited by the specific TSPO inhibitor 5-androsten-3,17,19-triol (19-Atriol). Additionally, we examined the in vivo effects of administering FGIN-1-27 to young and aged rats. In both cases, serum T levels increased significantly, consistent with the in vitro results. Indeed, serum T levels in aged rats administered FGIN-1-27 were equivalent to T levels in the serum of control young rats. Taken together, these results indicate that although there are reduced amounts of TSPO in aged Leydig cells, its direct activation is able to increase T production. We suggest that this approach might serve as a therapeutic means to increase steroid levels in vivo in cases of primary hypogonadism.

  19. Lecithin:Cholesterol Acyltransferase (LCAT) Deficiency Promotes Differentiation of Satellite Cells to Brown Adipocytes in a Cholesterol-dependent Manner.

    PubMed

    Nesan, Dinushan; Tavallaee, Ghazaleh; Koh, Deborah; Bashiri, Amir; Abdin, Rawand; Ng, Dominic S

    2015-12-18

    Our laboratory previously reported that lecithin:cholesterol acyltransferase (LCAT) and LDL receptor double knock-out mice (Ldlr(-/-)xLcat(-/-) or DKO) spontaneously develop functioning ectopic brown adipose tissue (BAT) in skeletal muscle, putatively contributing to protection from the diet-induced obesity phenotype. Here we further investigated their developmental origin and the mechanistic role of LCAT deficiency. Gene profiling of skeletal muscle in DKO newborns and adults revealed a classical lineage. Primary quiescent satellite cells (SC) from chow-fed DKO mice, not in Ldlr(-/-)xLcat(+/+) single-knock-out (SKO) or C57BL/6 wild type, were found to (i) express exclusively classical BAT-selective genes, (ii) be primed to express key functional BAT genes, and (iii) exhibit markedly increased ex vivo adipogenic differentiation into brown adipocytes. This gene priming effect was abrogated upon feeding the mice a 2% high cholesterol diet in association with accumulation of excess intracellular cholesterol. Ex vivo cholesterol loading of chow-fed DKO SC recapitulated the effect, indicating that cellular cholesterol is a key regulator of SC-to-BAT differentiation. Comparing adipogenicity of Ldlr(+/+)xLcat(-/-) (LCAT-KO) SC with DKO SC identified a role for LCAT deficiency in priming SC to express BAT genes. Additionally, we found that reduced cellular cholesterol is important for adipogenic differentiation, evidenced by increased induction of adipogenesis in cholesterol-depleted SC from both LCAT-KO and SKO mice. Taken together, we conclude that ectopic BAT in DKO mice is classical in origin, and its development begins in utero. We further showed complementary roles of LCAT deficiency and cellular cholesterol reduction in the SC-to-BAT adipogenesis.

  20. Role of GPx4 in human vascular endothelial cells, and the compensatory activity of brown rice on GPx4 ablation condition.

    PubMed

    Sakai, Osamu; Yasuzawa, Toshinori; Sumikawa, Yoshie; Ueta, Takashi; Imai, Hirotaka; Sawabe, Akiyoshi; Ueshima, Shigeru

    2017-03-01

    Oxidative stress is implicated in the pathologies of vascular endothelial cells. However, the importance of specific antioxidant enzymes in vascular endothelial cells is not fully understood. The purpose of this study was to elucidate the importance of Glutathione peroxidase 4 (GPx4), and the involvement of ferroptosis on cell death induced by GPx4 loss in human vascular endothelial cells. In addition, we examined the compensatory activity of brown rice on GPx4 ablation condition. Human umbilical vein endothelial cells were transfected with GPx4 or scramble control siRNA. GPx4 knockdown caused the increase in the levels of lipid oxidation, and induced cytotoxicity. On the other hand, α-tocopherol (vitamin E) and extract of brown rice, ameliorated lipid peroxidation, cytotoxicity, and delay of proliferation induced by GPx4 knockdown. Furthermore, ferrostatin-1, inhibitor of ferroptosis, also prevented cytotoxicity and delay of proliferation. In conclusion, our data demonstrated that GPx4 is an essential antioxidant enzyme for protecting lipid peroxidation, and is a regulator of ferroptosis in vascular endothelial cells. Furthermore, vitamin E rich food, such as brown rice, can compensate for GPx4 loss by protecting cells against lipid peroxidation.

  1. Protein kinase A-mediated cell proliferation in brown preadipocytes is independent of Erk1/2, PI{sub 3}K and mTOR

    SciTech Connect

    Wang, Yanling; Sato, Masaaki; Guo, Yuan; Bengtsson, Tore; Nedergaard, Jan

    2014-10-15

    The physiological agonist norepinephrine promotes cell proliferation of brown preadipocytes during the process of tissue recruitment. In a primary culture system, cAMP mediates these adrenergic effects. In the present study, we demonstrated that, in contrast to other systems where the mitogenic effect of cAMP requires the synergistic action of (serum) growth factors, especially insulin/IGF, the cAMP effect in brown preadipocytes was independent of serum and insulin. Protein kinase A, rather than Epac, mediated the cAMP mitogenic effect. The Erk 1/2 family of MAPK, the PI{sub 3}K system and the mTOR complexes were all activated by cAMP, but these activations were not necessary for cAMP-induced cell proliferation; a protein kinase C isoform may be involved in mediating cAMP-activated cell proliferation. We conclude that the generally acknowledged cellular mediators for induction of cell proliferation are not involved in this process in the brown preadipocyte system; this conclusion may be of relevance both for examination of mechanisms for induction of brown adipose tissue recruitment but also for understanding the mechanism behind e.g. certain endocrine neoplasias. - Highlights: • cAMP can mimick norepinephrine-induced proliferation of brown preadipocytes. • The cAMP-induced proliferation can occur in the absence of serum, of any other growth factors, and of insulin. • Erk1/2, PI{sub 3}K and mTOR are cAMP activated but not involved in induction of proliferation. • A Protein Kinase C member may be in the signalling cascade. • This pathway analysis may also be of importance for certain endocrine hyper- and neoplasias.

  2. Fat-specific protein 27 modulates nuclear factor of activated T cells 5 and the cellular response to stress

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Fat-specific protein 27 (FSP27), a member of the cell death-inducing DNA fragmentation factor a-like effector (Cide) family, is highly expressed in adipose tissues and is a lipid droplet (LD)-associated protein that induces the accumulation of LDs. Using a yeast two-hybrid system to examine potentia...

  3. Lipid Droplet Accumulation and Impaired Fat Efflux in Polarized Hepatic Cells: Consequences of Ethanol Metabolism

    PubMed Central

    McVicker, Benita L.; Rasineni, Karuna; Tuma, Dean J.; McNiven, Mark A.; Casey, Carol A.

    2012-01-01

    Steatosis, an early manifestation in alcoholic liver disease, is associated with the accumulation of hepatocellular lipid droplets (LDs). However, the role ethanol metabolism has in LD formation and turnover remains undefined. Here, we assessed LD dynamics following ethanol and oleic acid treatment to ethanol-metabolizing WIF-B cells (a hybrid of human fibroblasts (WI 38) and Fao rat hepatoma cells). An OA dose-dependent increase in triglyceride and stained lipids was identified which doubled (P < 0.05) in the presence of ethanol. This effect was blunted with the inclusion of an alcohol metabolism inhibitor. The ethanol/ OA combination also induced adipophilin, LD coat protein involved in the attenuation of lipolysis. Additionally, ethanol treatment resulted in a significant reduction in lipid efflux. These data demonstrate that the metabolism of ethanol in hepatic cells is related to LD accumulation, impaired fat efflux, and enhancements in LD-associated proteins. These alterations in LD dynamics may contribute to ethanol-mediated defects in hepatocellular LD regulation and the formation of steatosis. PMID:22506128

  4. Modulation of brown adipocyte activity by milk by-products: Stimulation of brown adipogenesis by buttermilk.

    PubMed

    Asano, Hiroki; Kida, Ryosuke; Muto, Kengo; Nara, Takayuki Y; Kato, Ken; Hashimoto, Osamu; Kawada, Teruo; Matsui, Tohru; Funaba, Masayuki

    2016-12-01

    Brown adipocytes dissipate chemical energy in the form of heat through the expression of mitochondrial uncoupling protein 1 (Ucp1); Ucp1 expression is further upregulated by the stimulation of β-adrenergic receptors in brown adipocytes. An increase in energy expenditure by activated brown adipocytes potentially contributes to the prevention of or therapeutics for obesity. The present study examined the effects of milk by-products, buttermilk and butter oil, on brown adipogenesis and the function of brown adipocytes. The treatment with buttermilk modulated brown adipogenesis, depending on the product tested; during brown adipogenesis, buttermilk 1 inhibited the differentiation of HB2 brown preadipocytes. In contrast, buttermilk 3 and 5 increased the expression of Ucp1 in the absence of isoproterenol (Iso), a β-adrenergic receptor agonist, suggesting the stimulation of brown adipogenesis. In addition, the Iso-induced expression of Ucp1 was enhanced by buttermilk 2 and 3. The treatment with buttermilk did not affect the basal or induced expression of Ucp1 by Iso in HB2 brown adipocytes, except for buttermilk 5, which increased the basal expression of Ucp1. Conversely, butter oil did not significantly affect the expression of Ucp1, irrespective of the cell phase of HB2 cells, ie, treatment during brown adipogenesis or of brown adipocytes. The results of the present study indicate that buttermilk is a regulator of brown adipogenesis and suggest its usefulness as a potential food material for antiobesity.

  5. Local Cell Death Changes the Orientation of Cell Division in the Developing Drosophila Wing Imaginal Disc Without Using Fat or Dachsous as Orienting Signals

    PubMed Central

    Kale, Abhijit; Rimesso, Gerard; Baker, Nicholas E.

    2016-01-01

    Drosophila imaginal disc cells exhibit preferred cell division orientations according to location within the disc. These orientations are altered if cell death occurs within the epithelium, such as is caused by cell competition or by genotypes affecting cell survival. Both normal cell division orientations, and their orientations after cell death, depend on the Fat-Dachsous pathway of planar cell polarity (PCP). The hypothesis that cell death initiates a planar polarity signal was investigated. When clones homozygous for the pineapple eye (pie) mutation were made to initiate cell death, neither Dachsous nor Fat was required in pie cells for the re-orientation of nearby cells, indicating a distinct signal for this PCP pathway. Dpp and Wg were also not needed for pie clones to re-orient cell division. Cell shapes were evaluated in wild type and mosaic wing discs to assess mechanical consequences of cell loss. Although proximal wing disc cells and cells close to the dorso-ventral boundary were elongated in their preferred cell division axes in wild type discs, cell shapes in much of the wing pouch were symmetrical on average and did not predict their preferred division axis. Cells in pie mutant clones were slightly larger than their normal counterparts, consistent with mechanical stretching following cell loss, but no bias in cell shape was detected in the surrounding cells. These findings indicate that an unidentified signal influences PCP-dependent cell division orientation in imaginal discs. PMID:28030539

  6. Local Cell Death Changes the Orientation of Cell Division in the Developing Drosophila Wing Imaginal Disc Without Using Fat or Dachsous as Orienting Signals.

    PubMed

    Kale, Abhijit; Rimesso, Gerard; Baker, Nicholas E

    2016-01-01

    Drosophila imaginal disc cells exhibit preferred cell division orientations according to location within the disc. These orientations are altered if cell death occurs within the epithelium, such as is caused by cell competition or by genotypes affecting cell survival. Both normal cell division orientations, and their orientations after cell death, depend on the Fat-Dachsous pathway of planar cell polarity (PCP). The hypothesis that cell death initiates a planar polarity signal was investigated. When clones homozygous for the pineapple eye (pie) mutation were made to initiate cell death, neither Dachsous nor Fat was required in pie cells for the re-orientation of nearby cells, indicating a distinct signal for this PCP pathway. Dpp and Wg were also not needed for pie clones to re-orient cell division. Cell shapes were evaluated in wild type and mosaic wing discs to assess mechanical consequences of cell loss. Although proximal wing disc cells and cells close to the dorso-ventral boundary were elongated in their preferred cell division axes in wild type discs, cell shapes in much of the wing pouch were symmetrical on average and did not predict their preferred division axis. Cells in pie mutant clones were slightly larger than their normal counterparts, consistent with mechanical stretching following cell loss, but no bias in cell shape was detected in the surrounding cells. These findings indicate that an unidentified signal influences PCP-dependent cell division orientation in imaginal discs.

  7. Epicardial fat: a new cardiovascular therapeutic target.

    PubMed

    Iacobellis, Gianluca

    2016-04-01

    Epicardial fat is the visceral fat depot of the heart. Given its rapid metabolism, organ fat specificity and simple objective measurability, epicardial fat can serve as target for pharmaceutical agents targeting the adipose tissue. Epicardial fat has shown to significantly respond to thiazolidinediones, glucagon like peptide 1 receptor agonists, dipeptidyl peptidase-4 inhibitors and statins. Epicardial fat may represent a measurable risk factor and modifiable therapeutic target. Targeted pharmaceutical interventions may allow the epicardial fat to resume its physiological role. A drug-induced browning effect on epicardial fat suggests the development of pharmacological strategies to increase energy consumption. The potential of modulating the epicardial fat transcriptome with targeted pharmacological agents can open new avenues in the pharmacotherapy of cardio-metabolic diseases.

  8. Chondrogenesis of Human Infrapatellar Fat Pad Stem Cells on Acellular Dermal Matrix

    PubMed Central

    Ye, Ken; Traianedes, Kathy; Choong, Peter F. M.; Myers, Damian E.

    2016-01-01

    Acellular dermal matrix (ADM) has been in clinical use for decades in numerous surgical applications. The ability for ADM to promote cellular repopulation, revascularisation and tissue regeneration is well documented. Adipose stem cells have the ability to differentiate into mesenchymal tissue types, including bone and cartilage. The aim of this study was to investigate the potential interaction between ADM and adipose stem cells in vitro using TGFβ3 and BMP6. Human infrapatellar fat pad-derived adipose stem cells (IPFP-ASC) were cultured with ADM derived from rat dermis in chondrogenic (TGFβ3 and BMP6) medium in vitro for 2 and 4 weeks. Histology, qPCR, and immunohistochemistry were performed to assess for markers of chondrogenesis (collagen Type II, SOX9 and proteoglycans). At 4 weeks, cell-scaffold constructs displayed cellular changes consistent with chondrogenesis, with evidence of stratification of cell layers and development of a hyaline-like cartilage layer superficially, which stained positively for collagen Type II and proteoglycans. Significant cell–matrix interaction was seen between the cartilage layer and the ADM itself with seamless integration between each layer. Real time qPCR showed significantly increased COL2A1, SOX9, and ACAN gene expression over 4 weeks when compared to control. COL1A2 gene expression remained unchanged over 4 weeks. We believe that the principles that make ADM versatile and successful for tissue regeneration are applicable to cartilage regeneration. This study demonstrates in vitro the ability for IPFP-ASCs to undergo chondrogenesis, infiltrate, and interact with ADM. These outcomes serve as a platform for in vivo modelling of ADM for cartilage repair. PMID:26858950

  9. Involvement of cysteinyl leukotrienes in airway smooth muscle cell DNA synthesis after repeated allergen exposure in sensitized Brown Norway rats

    PubMed Central

    Salmon, Michael; Walsh, David A; Huang, Tung-Jung; Barnes, Peter J; Leonard, Thomas B; Hay, Douglas W P; Chung, K Fan

    1999-01-01

    Airway smooth muscle thickening is a characteristic feature of airway wall remodelling in chronic asthma. We have investigated the role of the leukotrienes in airway smooth muscle (ASM) and epithelial cell DNA synthesis and ASM thickening following repeated allergen exposure in Brown Norway rats sensitized to ovalbumin. There was a 3 fold increase in ASM cell DNA synthesis, as measured by percentage bromodeoxyuridine (BrdU) incorporation, in repeatedly ovalbumin-exposed (4.1%, 3.6–4.6; mean, 95% c.i.) compared to chronically saline-exposed rats (1.3%, 0.6–2.1; P<0.001). Treatment with a 5-lipoxygenase enzyme inhibitor (SB 210661, 10 mg kg−1, p.o.) and a specific cysteinyl leukotriene (CysLT1) receptor antagonist, pranlukast (SB 205312, 30 mg kg−1, p.o.), both attenuated ASM cell DNA synthesis. Treatment with a specific leukotriene B4 (BLT) receptor antagonist (SB 201146, 15 mg kg−1, p.o.) had no effect. There was also a significant, 2 fold increase in the number of epithelial cells incorporating BrdU per unit length of basement membrane after repeated allergen exposure. This response was not inhibited by treatment with SB 210661, pranlukast or SB 201146. A significant increase in ASM thickness was identified following repeated allergen exposure and this response was attenuated significantly by SB 210661, pranlukast and SB 201146. Rats exposed to chronic allergen exhibited bronchial hyperresponsiveness to acetylcholine and had significant eosinophil recruitment into the lungs. Treatment with SB 210661, pranlukast or SB 201146 significantly attenuated eosinophil recruitment into the lungs, whilst having no significant effect on airway hyperresponsiveness. These data indicate that the cysteinyl leukotrienes are important mediators in allergen-induced ASM cell DNA synthesis in rats, while both LTB4 and cysteinyl leukotrienes contribute to ASM thickening and eosinophil recruitment following repeated allergen exposure. PMID:10455261

  10. Steroidogenic fate of the Leydig cells that repopulate the testes of young and aged Brown Norway rats after elimination of the preexisting Leydig cells.

    PubMed

    Chen, Haolin; Guo, Jingjing; Ge, Renshan; Lian, Qingquan; Papadopoulos, Vassilios; Zirkin, Barry R

    2015-12-01

    The capacity of Brown Norway rat Leydig cells to produce testosterone (T) decreases with aging. In a previous study, we reported that a new generation of Leydig cells can be restored in both young and old rat testes after a single injection of ethane dimethanesulfonate (EDS), and that the abilities of the new Leydig cells in young and old rats to produce T were equivalent. Our objective herein was to compare the steroidogenic fate of the new Leydig cells over time. Young (3 month-old) and old (18 month-old) rats were injected with EDS to eliminate the existing Leydig cells. Ten weeks after EDS, Leydig cells had been restored and T production by the new Leydig cells isolated from young and old rat testes was equivalent. Thirty weeks after EDS treatment of young rats, the ability of the new Leydig cells to produce T had not diminished from 10 weeks post-EDS. In contrast, at 30 weeks post-EDS, T production by new cells in old rat testes was reduced significantly from the 10-week level. Serum T levels at 10 and 30 weeks were consistent with Leydig cell T production. Serum LH levels did not differ in any group. Thus, although the Leydig cells restored to both young and old rats after EDS initially produced T at high, equivalent levels, the cells in the old testes did not maintain this ability. These results suggest that: 1) the cells from which new populations of Leydig cells are derived may differ depending upon the age of the rat; and/or 2) factors extrinsic to the new Leydig cells in young and old testes differ, and it is these differences that are responsible for reductions in T by the newly formed Leydig cells in the testes of old rats.

  11. High fat diet triggers cell cycle arrest and excessive apoptosis of granulosa cells during the follicular development.

    PubMed

    Wu, Yanqing; Zhang, Zhenghong; Liao, Xinghui; Wang, Zhengchao

    2015-10-23

    The regulatory mechanism of granulosa cells (GCs) proliferation during the follicular development is complicated and multifactorial, which is essential for the oocyte growth and normal ovarian functions. To investigate the role of high fat diet (HFD) on the proliferation of GCs, 4-week old female mice were fed with HFD or normal control diet (NC) for 15 weeks or 20 weeks and then detected the expression level of some regulatory molecules of cell cycle and apoptosis. The abnormal ovarian morphology was observed at 20 weeks. Further mechanistic studies indicated that HFD induced-obesity caused elevated apoptotic levels in GCs of the ovaries in a time-dependent manner. Moreover, cell cycle progress was also impacted after HFD fed. The cell cycle inhibitors, p27(Kip1) and p21(Cip1), were significantly induced in the ovaries from the mice in HFD group when compared with that in the ovaries from the mice in NC group. Subsequently, the expression levels of Cyclin D1, D3 and CDK4 were also significantly influenced in the ovaries from the mice fed with HFD in a time-dependent manner. The present results suggested that HFD induced-obesity may trigger cell cycle arrest and excessive apoptosis of GCs, causing the abnormal follicular development and ovarian function failure.

  12. Facts about saturated fats

    MedlinePlus

    Cholesterol - saturated fat; Atherosclerosis - saturated fat; Hardening of the arteries - saturated fat; Hyperlipidemia - saturated fat; Hypercholesterolemia - saturated fat; Coronary artery disease - saturated fat; ...

  13. Fat depot-specific gene signature and ECM remodeling of Sca1(high) adipose-derived stem cells.

    PubMed

    Tokunaga, Masakuni; Inoue, Mayumi; Jiang, Yibin; Barnes, Richard H; Buchner, David A; Chun, Tae-Hwa

    2014-06-01

    Stem cell antigen-1 (Sca1 or Ly6A/E) is a cell surface marker that is widely expressed in mesenchymal stem cells, including adipose-derived stem cells (ASCs). We hypothesized that the fat depot-specific gene signature of Sca1(high) ASCs may play the major role in defining adipose tissue function and extracellular matrix (ECM) remodeling in a depot-specific manner. Herein we aimed to characterize the unique gene signature and ECM remodeling of Sca1(high) ASCs isolated from subcutaneous (inguinal) and visceral (epididymal) adipose tissues. Sca1(high) ASCs are found in the adventitia and perivascular areas of adipose tissues. Sca1(high) ASCs purified with magnetic-activated cell sorting (MACS) demonstrate dendrite or round shape with the higher expression of cytokines and chemokines (e.g., Il6, Cxcl1) and the lower expression of a glucose transporter (Glut1). Subcutaneous and visceral fat-derived Sca1(high) ASCs particularly differ in the gene expressions of adhesion and ECM molecules. While the expression of the major membrane-type collagenase (MMP14) is comparable between the groups, the expressions of secreted collagenases (MMP8 and MMP13) are higher in visceral Sca1(high) ASCs than in subcutaneous ASCs. Consistently, slow but focal MMP-dependent collagenolysis was observed with subcutaneous adipose tissue-derived vascular stromal cells, whereas rapid and bulk collagenolysis was observed with visceral adipose tissue-derived cells in MMP-dependent and -independent manners. These results suggest that the fat depot-specific gene signatures of ASCs may contribute to the distinct patterns of ECM remodeling and adipose function in different fat depots.

  14. A rapid sonication based method for preparation of stromal vascular fraction and mesenchymal stem cells from fat tissue

    PubMed Central

    Amirkhani, Mohammad Amir; Mohseni, Rashin; Soleimani, Masoud; Shoae-Hassani, Alireza; Nilforoushzadeh, Mohammad Ali

    2016-01-01

    Introduction: Much attention has been paid to the idea of cell therapy using stem cells from different sources of the body. Fat-derived stem cells that are called adipose derived stem cells (ADSCs) from stromal vascular fraction (SVF) are the subject of many studies in several cell therapy clinical trials. Despite production of some GMP-grade enzymes to isolate SVF for clinical trials, there are critical conditions like inconsistency in lot-to-lot enzyme activity, endotoxin residues, other protease activities and cleavage of some cell surface markers which significantly narrow the options. So we decided to develop a new method via sonication cavitation to homogenize fat tissue and disrupt partially adipose cells to obtain SVF and finally ADSCs at a minimum of time and expenses. Methods: The fat tissue was chopped in a sterile condition by a blender mixer and then sonicated for 2 s before centrifugation. The next steps were performed as the regular methods of SVF harvesting, and then it was characterized using flow cytometry. Results: Analysis of the surface markers of the cells revealed similar sets of surface antigens. The cells showed slightly high expression of CD34, CD73 and CD105. The differentiation capacity of these cells indicates that multipotent properties of the cells are not compromised after sonication. But we had the less osteogenic potential of cells when compared with the enzymatic method. Conclusion: The current protocol based on the sonication-mediated cavitation is a rapid, safe and cost-effective method, which is proposed for isolation of SVF and of course ADSCs cultures in a large scale for the clinical trials or therapeutic purposes. PMID:27525227

  15. A Soluble Form of the Giant Cadherin Fat1 Is Released from Pancreatic Cancer Cells by ADAM10 Mediated Ectodomain Shedding

    PubMed Central

    Wojtalewicz, Nathalie; Klein-Scory, Susanne; Hahn, Stephan; Schmiegel, Wolff; Warnken, Uwe; Schnölzer, Martina; de Bock, Charles E.

    2014-01-01

    In pancreatic cancer, there is a clear unmet need to identify new serum markers for either early diagnosis, therapeutic stratification or patient monitoring. Proteomic analysis of tumor cell secretomes is a promising approach to indicate proteins released from tumor cells in vitro. Ectodomain shedding of transmembrane proteins has previously been shown to contribute significant fractions the tumor cell secretomes and to generate valuable serum biomarkers. Here we introduce a soluble form of the giant cadherin Fat1 as a novel biomarker candidate. Fat1 expression and proteolytic processing was analyzed by mass spectrometry and Western blotting using pancreatic cancer cell lines as compared to human pancreatic ductal epithelial cells. RNA expression in cancer tissues was assessed by in silico analysis of publically available microarray data. Involvement of ADAM10 (A Disintegrin and metalloproteinase domain-containing protein 10) in Fat1 ectodomain shedding was analyzed by chemical inhibition and knockdown experiments. A sandwich ELISA was developed to determine levels of soluble Fat1 in serum samples. In the present report we describe the release of high levels of the ectodomain of Fat1 cadherin into the secretomes of human pancreatic cancer cells in vitro, a process that is mediated by ADAM10. We confirm the full-length and processed heterodimeric form of Fat1 expressed on the plasma membrane and also show the p60 C-terminal transmembrane remnant fragment corresponding to the shed ectodomain. Fat1 and its sheddase ADAM10 are overexpressed in pancreatic adenocarcinomas and ectodomain shedding is also recapitulated in vivo leading to increased Fat1 serum levels in some pancreatic cancer patients. We suggest that soluble Fat1 may find an application as a marker for patient monitoring complementing carbohydrate antigen 19-9 (CA19-9). In addition, detailed analysis of the diverse processed protein isoforms of the candidate tumor suppressor Fat1 can also contribute to our

  16. Cannabidiol promotes browning in 3T3-L1 adipocytes.

    PubMed

    Parray, Hilal Ahmad; Yun, Jong Won

    2016-05-01

    Recruitment of the brown-like phenotype in white adipocytes (browning) and activation of existing brown adipocytes are currently being investigated as a means to combat obesity. Thus, a wide variety of dietary agents that contribute to browning of white adipocytes have been identified. The present study was designed to investigate the effects of cannabidiol (CBD), a major nonpsychotropic phytocannabinoid of Cannabis sativa, on induction of browning in 3T3-L1 adipocytes. CBD enhanced expression of a core set of brown fat-specific marker genes (Ucp1, Cited1, Tmem26, Prdm16, Cidea, Tbx1, Fgf21, and Pgc-1α) and proteins (UCP1, PRDM16, and PGC-1α). Increased expression of UCP1 and other brown fat-specific markers contributed to the browning of 3T3-L1 adipocytes possibly via activation of PPARγ and PI3K. In addition, CBD increased protein expression levels of CPT1, ACSL, SIRT1, and PLIN while down-regulating JNK2, SREBP1, and LPL. These data suggest possible roles for CBD in browning of white adipocytes, augmentation of lipolysis, thermogenesis, and reduction of lipogenesis. In conclusion, the current data suggest that CBD plays dual modulatory roles in the form of inducing the brown-like phenotype as well as promoting lipid metabolism. Thus, CBD may be explored as a potentially promising therapeutic agent for the prevention of obesity.

  17. MicroRNAs Are Required for the Feature Maintenance and Differentiation of Brown Adipocytes

    PubMed Central

    Kim, Hye-Jin; Cho, Hyunjii; Alexander, Ryan; Patterson, Heide Christine; Gu, Minxia; Lo, Kinyui Alice; Xu, Dan; Goh, Vera J.; Nguyen, Long N.; Chai, Xiaoran; Huang, Cher X.; Kovalik, Jean-Paul; Ghosh, Sujoy; Trajkovski, Mirko; Silver, David L.; Lodish, Harvey

    2014-01-01

    Brown adipose tissue (BAT) is specialized to burn lipids for heat generation as a natural defense against cold and obesity. Previous studies established microRNAs (miRNAs) as essential regulators of brown adipocyte differentiation, but whether miRNAs are required for the feature maintenance of mature brown adipocytes remains unknown. To address this question, we ablated Dgcr8, a key regulator of the miRNA biogenesis pathway, in mature brown as well as in white adipocytes. Adipose tissue–specific Dgcr8 knockout mice displayed enlarged but pale interscapular brown fat with decreased expression of genes characteristic of brown fat and were intolerant to cold exposure. Primary brown adipocyte cultures in vitro confirmed that miRNAs are required for marker gene expression in mature brown adipocytes. We also demonstrated that miRNAs are essential for the browning of subcutaneous white adipocytes in vitro and in vivo. Using this animal model, we performed miRNA expression profiling analysis and identified a set of BAT-specific miRNAs that are upregulated during brown adipocyte differentiation and enriched in brown fat compared with other organs. We identified miR-182 and miR-203 as new regulators of brown adipocyte development. Taken together, our study demonstrates an essential role of miRNAs in the maintenance as well as in the differentiation of brown adipocytes. PMID:25008181

  18. Elucidating fish oil-induced milk fat depression in dairy sheep: Milk somatic cell transcriptome analysis

    PubMed Central

    Suárez-Vega, Aroa; Toral, Pablo G.; Gutiérrez-Gil, Beatriz; Hervás, Gonzalo; Arranz, Juan José; Frutos, Pilar

    2017-01-01

    In this study, RNA sequencing was used to obtain a comprehensive profile of the transcriptomic changes occurring in the mammary gland of lactating sheep suffering from fish oil-induced milk fat depression (FO-MFD). The milk somatic cell transcriptome analysis of four control and four FO-MFD ewes generated an average of 42 million paired-end reads per sample. In both conditions, less than 220 genes constitute approximately 89% of the total counts. These genes, which are considered as core genes, were mainly involved in cytoplasmic ribosomal proteins and electron transport chain pathways. In total, 117 genes were upregulated, and 96 genes were downregulated in FO-MFD samples. Functional analysis of the latter indicated a downregulation of genes involved in the SREBP signaling pathway (e.g., ACACA, ACSL, and ACSS) and Gene Ontology terms related to lipid metabolism and lipid biosynthetic processes. Integrated interpretation of upregulated genes indicated enrichment in genes encoding plasma membrane proteins and proteins regulating protein kinase activity. Overall, our results indicate that FO-MFD is associated with the downregulation of key genes involved in the mammary lipogenesis process. In addition, the results also suggest that this syndrome may be related to upregulation of other genes implicated in signal transduction and codification of transcription factors. PMID:28378756

  19. Sensorial pedagogies, hungry fat cells and the limits of nutritional health education

    PubMed Central

    Sanabria, Emilia

    2015-01-01

    This article examines the way the category of ‘the sensorial' is mobilised across obesity research and care practices for overweight persons in France. The ‘natural' body is understood to have developed mechanisms that motivate eaters to seek out energy-dense foods, a hardwiring that is maladaptive in today's plethoric food environment. The article analyses the feedback models mobilised in scientific literature on the neuroendocrine processes regulating appetite. The analysis of how ‘the sensorial' is studied and used to treat patients provides a vantage point onto the ways foods and bodies transform each other. Recent findings show that fat cells influence metabolism by secreting hormones, revealing that eaters are affected by the materiality of the foods they ingest. ‘The sensorial' functions as a regulator in the feedback mechanisms where social norms regulating foodscapes become enfolded in the molecular processes that control appetite regulation. The article traces the work that the category of ‘the sensorial' does as it flows through the loops and feedbacks between scientific evidence, policy and care. It examines the way pleasure and the sensations of eaters are increasingly foregrounded in French nutritional health promotion strategies in a context where informing eaters is increasingly deemed ineffective. PMID:26157470

  20. Elucidating fish oil-induced milk fat depression in dairy sheep: Milk somatic cell transcriptome analysis.

    PubMed

    Suárez-Vega, Aroa; Toral, Pablo G; Gutiérrez-Gil, Beatriz; Hervás, Gonzalo; Arranz, Juan José; Frutos, Pilar

    2017-04-05

    In this study, RNA sequencing was used to obtain a comprehensive profile of the transcriptomic changes occurring in the mammary gland of lactating sheep suffering from fish oil-induced milk fat depression (FO-MFD). The milk somatic cell transcriptome analysis of four control and four FO-MFD ewes generated an average of 42 million paired-end reads per sample. In both conditions, less than 220 genes constitute approximately 89% of the total counts. These genes, which are considered as core genes, were mainly involved in cytoplasmic ribosomal proteins and electron transport chain pathways. In total, 117 genes were upregulated, and 96 genes were downregulated in FO-MFD samples. Functional analysis of the latter indicated a downregulation of genes involved in the SREBP signaling pathway (e.g., ACACA, ACSL, and ACSS) and Gene Ontology terms related to lipid metabolism and lipid biosynthetic processes. Integrated interpretation of upregulated genes indicated enrichment in genes encoding plasma membrane proteins and proteins regulating protein kinase activity. Overall, our results indicate that FO-MFD is associated with the downregulation of key genes involved in the mammary lipogenesis process. In addition, the results also suggest that this syndrome may be related to upregulation of other genes implicated in signal transduction and codification of transcription factors.

  1. High Fat Diet Regulation of β-Cell Proliferation and β-Cell Mass

    PubMed Central

    Golson, M.L.; Misfeldt, A. Ackermann; Kopsombut, U.G.; Petersen, C.P.; Gannon, M.

    2013-01-01

    Type 2 Diabetes (T2D) is characterized by relative insulin insufficiency, caused when peripheral tissues such as liver, muscle, and adipocytes have a decreased response to insulin. One factor that elevates the risk for insulin resistance and T2D is obesity. In obese patients without T2D and initially in people who develop T2D, pancreatic β-cells are able to compensate for insulin resistance by increasing β-cell mass, effected by increased proliferation and hypertrophy, as well as increased insulin secretion per β-cell. In patients that go on to develop T2D, however, this initial period of compensation is followed by β-cell failure due to decreased proliferation and increased apoptosis. The forkhead box transcription factor FoxM1 is required for β-cell replication in mice after four weeks of age, during pregnancy, and after partial pancreatectomy. We investigated whether it is also required for β-cell proliferation due to diet-induced obesity. PMID:24339840

  2. Purinergic receptor stimulation increases membrane trafficking in brown adipocytes

    PubMed Central

    1996-01-01

    Stimulation of brown adipocytes by their sympathetic innervation plays a major role in body energy homeostasis by regulating the energy- wasting activity of the tissue. The norepinephrine released by sympathetic activity acts on adrenergic receptors to activate a variety of metabolic and membrane responses. Since sympathetic stimulation may also release vesicular ATP, we tested brown fat cells for ATP responses. We find that micromolar concentrations of extracellular ATP initiates profound changes in the membrane trafficking of brown adipocytes. ATP elicited substantial increases in total cell membrane capacitance, averaging approximately 30% over basal levels and occurring on a time scale of seconds to minutes. The membrane capacitance increase showed an agonist sensitivity of 2-methylthio-ATP > or = ATP > ADP > > adenosine, consistent with mediation by a P2r type purinergic receptor. Membrane capacitance increases were not seen when cytosolic calcium was increased by adrenergic stimulation, and capacitance responses to ATP were similar in the presence and absence of extracellular calcium. These results indicate that increases in cytosolic calcium alone do not mediate the membrane response to ATP. Photometric assessment of surface-accessible membrane using the dye FM1- 43 showed that ATP caused an approximate doubling of the amount of membrane actively trafficking with the cell surface. The discrepancy in the magnitudes of the capacitance and fluorescence changes suggests that ATP both activates exocytosis and alters other aspects of membrane handling. These findings suggest that secretion, mobilization of membrane transporters, and/or surface membrane expression of receptors may be regulated in brown adipocytes by P2r purinergic receptor activity. PMID:8923265

  3. An immunohistochemical study on the gastrointestinal endocrine cells of three honeyeaters: singing honeyeater (Meliphaga virescens), spiny-cheeked honeyeater (Acanthogenys rufogularis) and brown honeyeater (Lichmera indistincta).

    PubMed

    Hashimoto, N; Yamada, J; Richardson, K C; Kitamura, N; Yamashita, T

    1993-01-01

    The gastrointestinal endocrine cells of the singing honeyeater (Meliphaga virescens), spiny-cheeked honeyeater (Acanthogenys rufogularis) and brown honeyeater (Lichmera indistincta) were studied immunohistochemically with special reference to their degree of dependency upon nectar. The nine types of immunoreactive endocrine cells were detected in their gastrointestinal mucosa. Coexistence of motilin and serotonin in the same cells was confirmed in the pyloric region. In the duodenum and jejunum, a few peptide tyrosin tyrosin (PYY)-immunoreactive cells were detected. The clear difference in the distribution and frequency of the gastrointestinal endocrine cells among three types of honeyeaters, which differ in the degree of dependency upon the nectar, could not be confirmed. However, some differences were found that serotonin-, somatostatin- and gastrin-releasing peptide (GRP)-immunoreactive cells in the gizzard, gastrin-immunoreactive cells in the duodenum and jejunum, enteroglucagon-immunoreactive cells in the caeca and in the colon, and pancreatic glucagon-immunoreactive cells in the ileum of brown honeyeaters were more numerous (p < 0.05) than other two species.

  4. Transplantation of a mammary stromal cell line into a mammary fat pad: development of the site-specific in vivo analysis system for mammary stromal cells.

    PubMed

    Nakatani, Hajime; Aoki, Naohito; Nadano, Daita; Matsuda, Tsukasa

    2011-01-01

    The interaction between mammary epithelial and stromal tissue is considered to be important in breast tissue development. In this study, we developed a transplantation procedure for the mammary stromal fibroblastic cell line (MSF) to examine its life in vivo. First we established MSF cells which stably expressed lacZ (lacZ/MSF) and had characteristics of mammary stromal cells. The lacZ/MSF cells were then transplanted into a cleared mammary fat pad of syngenic mice with and without mammary primary epithelial organoids. Whole mount X-gal and carmine staining of the transplants revealed that a number of undifferentiated lacZ/MSF cells survived around the mammary epithelial tissue when transplanted with organoids. These results indicate that transplantation of MSF cells into mammary fat pad was accomplished by co-transplantation with primary mammary organoids. Finally, we discuss the application of transplantation procedure for in vivo studies of the mammary stromal tissue development and stromal-epithelial interactions.

  5. A high fat diet containing saturated but not unsaturated fatty acids enhances T cell receptor clustering on the nanoscale.

    PubMed

    Shaikh, Saame Raza; Boyle, Sarah; Edidin, Michael

    2015-09-01

    Cell culture studies show that the nanoscale lateral organization of surface receptors, their clustering or dispersion, can be altered by changing the lipid composition of the membrane bilayer. However, little is known about similar changes in vivo, which can be effected by changing dietary lipids. We describe the use of a newly developed method, k-space image correlation spectroscopy, kICS, for analysis of quantum dot fluorescence to show that a high fat diet can alter the nanometer-scale clustering of the murine T cell receptor, TCR, on the surface of naive CD4(+) T cells. We found that diets enriched primarily in saturated fatty acids increased TCR nanoscale clustering to a level usually seen only on activated cells. Diets enriched in monounsaturated or n-3 polyunsaturated fatty acids had no effect on TCR clustering. Also none of the high fat diets affected TCR clustering on the micrometer scale. Furthermore, the effect of the diets was similar in young and middle aged mice. Our data establish proof-of-principle that TCR nanoscale clustering is sensitive to the composition of dietary fat.

  6. Gender-Specific Mechanisms Underlying the Amelioration of High-Fat Diet-Induced Glucose Intolerance in B-Cell-Activating Factor Deficient Mice

    PubMed Central

    Kim, Bobae; Hyun, Chang-Kee

    2016-01-01

    It has recently been found that B cell activating factor (BAFF) plays an important role in the regulation of energy homeostasis. We also have previously reported that BAFF deficiency reverses high-fat (HF) diet-induced glucose intolerance by potentiating adipose tissue function. In the present study, we found that BAFF deficient (BAFF-/-) mice exhibit gender-specific differences in protection against diet-induced glucose intolerance, and aimed to characterize the gender-dependent molecular alterations in energy metabolism. Under HF feeding conditions, serum BAFF level of female wild-type (WT) mice was considerably higher than that of male mice. Despite increased body weight gain, both male and female BAFF-/- mice showed significantly improved glucose tolerance compared to their WT counterparts. Expressions of genes involved in glucose transport, thermogenesis and lipid oxidation were up-regulated in brown adipose tissues of both male and female BAFF-/- mice. Interestingly, the expression of thermogenic genes in subcutaneous adipose tissue was significantly enhanced in female BAFF-/- compared to WT mice, but the difference was not observed between male BAFF-/- and WT mice. The enhanced thermogenic program was confirmed by higher protein levels of UCP1 and irisin in female BAFF-/- than in WT mice. Additionally, adiponectin production in white adipose tissues and AMPK phosphorylation in subcutaneous adipose tissue were also significantly elevated in female BAFF-/- compared to WT mice, but not in male BAFF-/- mice. Our findings define a comprehensive scenario for the enhancing effect of BAFF depletion on glucose tolerance wherein the underlying mechanism is, at least in part, gender-specific, and suggest that gender difference should be considered as an important factor in the use of BAFF blockade as a therapeutic approach for the prevention and treatment of type 2 diabetes. PMID:27814392

  7. Transcriptional Pathways in cPGI2-Induced Adipocyte Progenitor Activation for Browning

    PubMed Central

    Bayindir, Irem; Babaeikelishomi, Rohollah; Kocanova, Silvia; Sousa, Isabel Sofia; Lerch, Sarah; Hardt, Olaf; Wild, Stefan; Bosio, Andreas; Bystricky, Kerstin; Herzig, Stephan; Vegiopoulos, Alexandros

    2015-01-01

    De novo formation of beige/brite adipocytes from progenitor cells contributes to the thermogenic adaptation of adipose tissue and holds great potential for the therapeutic remodeling of fat as a treatment for obesity. Despite the recent identification of several factors regulating browning of white fat, there is a lack of physiological cell models for the mechanistic investigation of progenitor-mediated beige/brite differentiation. We have previously revealed prostacyclin (PGI2) as one of the few known endogenous extracellular mediators promoting de novo beige/brite formation by relaying β-adrenergic stimulation to the progenitor level. Here, we present a cell model based on murine primary progenitor cells defined by markers previously shown to be relevant for in vivo browning, including a simplified isolation procedure. We demonstrate the specific and broad induction of thermogenic gene expression by PGI2 signaling in the absence of lineage conversion, and reveal the previously unidentified nuclear relocalization of the Ucp1 gene locus in association with transcriptional activation. By profiling the time course of the progenitor response, we show that PGI2 signaling promoted progenitor cell activation through cell cycle and adhesion pathways prior to metabolic maturation toward an oxidative cell phenotype. Our results highlight the importance of core progenitor activation pathways for the recruitment of thermogenic cells and provide a resource for further mechanistic investigation. PMID:26347713

  8. Clonal analyses and gene profiling identify genetic biomarkers of the thermogenic potential of human brown and white preadipocytes.

    PubMed

    Xue, Ruidan; Lynes, Matthew D; Dreyfuss, Jonathan M; Shamsi, Farnaz; Schulz, Tim J; Zhang, Hongbin; Huang, Tian Lian; Townsend, Kristy L; Li, Yiming; Takahashi, Hirokazu; Weiner, Lauren S; White, Andrew P; Lynes, Maureen S; Rubin, Lee L; Goodyear, Laurie J; Cypess, Aaron M; Tseng, Yu-Hua

    2015-07-01

    Targeting brown adipose tissue (BAT) content or activity has therapeutic potential for treating obesity and the metabolic syndrome by increasing energy expenditure. However, both inter- and intra-individual differences contribute to heterogeneity in human BAT and potentially to differential thermogenic capacity in human populations. Here we generated clones of brown and white preadipocytes from human neck fat and characterized their adipogenic and thermogenic differentiation. We combined an uncoupling protein 1 (UCP1) reporter system and expression profiling to define novel sets of gene signatures in human preadipocytes that could predict the thermogenic potential of the cells once they were maturated. Knocking out the positive UCP1 regulators, PREX1 and EDNRB, in brown preadipocytes using CRISPR-Cas9 markedly abolished the high level of UCP1 in brown adipocytes differentiated from the preadipocytes. Finally, we were able to prospectively isolate adipose progenitors with great thermogenic potential using the cell surface marker CD29. These data provide new insights into the cellular heterogeneity in human fat and offer potential biomarkers for identifying thermogenically competent preadipocytes.

  9. Adrenergic regulation of cellular plasticity in brown, beige/brite and white adipose tissues.

    PubMed

    Ramseyer, Vanesa D; Granneman, James G

    2016-01-01

    The discovery of brown adipose tissue in adult humans along with the recognition of adipocyte heterogeneity and plasticity of white fat depots has renewed the interest in targeting adipose tissue for therapeutic benefit. Adrenergic activation is a well-established means of recruiting catabolic adipocyte phenotypes in brown and white adipose tissues. In this article, we review mechanisms of brown adipocyte recruitment by the sympathetic nervous system and by direct β-adrenergic receptor activation. We highlight the distinct modes of brown adipocyte recruitment in brown, beige/brite, and white adipose tissues, UCP1-independent thermogenesis, and potential non-thermogenic, metabolically beneficial effects of brown adipocytes.

  10. Reproducible Volume Restoration and Efficient Long-term Volume Retention after Point-of-care Standardized Cell-enhanced Fat Grafting in Breast Surgery

    PubMed Central

    Dos Anjos, Severiano; Matas-Palau, Aina; Mercader, Josep; Katz, Adam J.

    2015-01-01

    Background: Lipoaspirated fat grafts are used to reconstruct volume defects in breast surgery. Although intraoperative treatment decisions are influenced by volume changes observed immediately after grafting, clinical effect and patient satisfaction are dependent on volume retention over time. The study objectives were to determine how immediate breast volume changes correlate to implanted graft volumes, to understand long-term adipose graft volume changes, and to study the “dose” effect of adding autologous stromal vascular fraction (SVF) cells to fat grafts on long-term volume retention. Methods: A total of 74 patients underwent 77 cell-enhanced fat grafting procedures to restore breast volume deficits associated with cosmetic and reconstructive indications. Although all procedures used standardized fat grafts, 21 of the fat grafts were enriched with a low dose of SVF cells and 56 were enriched with a high SVF cell dose. Three-dimensional imaging was used to quantify volume retention over time Results: For each milliliter of injected fat graft, immediate changes in breast volume were shown to be lower than the actual volume implanted for all methods and clinical indications treated. Long-term breast volume changes stabilize by 90–120 days after grafting. Final volume retention in the long-term was higher with high cell-enhanced fat grafts. Conclusions: Intraoperative immediate breast volume changes do not correspond with implanted fat graft volumes. In the early postoperative period (7–21 days), breast volume increases more than the implanted volume and then rapidly decreases in the subsequent 30–60 days. High-dose cell-enhanced fat grafts decrease early postsurgical breast edema and significantly improve long-term volume retention. PMID:26579353

  11. Deletion of Inducible Nitric-Oxide Synthase in Leptin-Deficient Mice Improves Brown Adipose Tissue Function

    PubMed Central

    Becerril, Sara; Rodríguez, Amaia; Catalán, Victoria; Sáinz, Neira; Ramírez, Beatriz; Collantes, María; Peñuelas, Iván; Gómez-Ambrosi, Javier; Frühbeck, Gema

    2010-01-01

    Background Leptin and nitric oxide (NO) on their own participate in the control of non-shivering thermogenesis. However, the functional interplay between both factors in this process has not been explored so far. Therefore, the aim of the present study was to analyze the impact of the absence of the inducible NO synthase (iNOS) gene in the regulation of energy balance in ob/ob mice. Methods and Findings Double knockout (DBKO) mice simultaneously lacking the ob and iNOS genes were generated, and the expression of molecules involved in the control of brown fat cell function was analyzed by real-time PCR, western-blot and immunohistochemistry. Twelve week-old DBKO mice exhibited reduced body weight (p<0.05), decreased amounts of total fat pads (p<0.05), lower food efficiency rates (p<0.05) and higher rectal temperature (p<0.05) than ob/ob mice. Ablation of iNOS also improved the carbohydrate and lipid metabolism of ob/ob mice. DBKO showed a marked reduction in the size of brown adipocytes compared to ob/ob mutants. In this sense, in comparison to ob/ob mice, DBKO rodents showed an increase in the expression of PR domain containing 16 (Prdm16), a transcriptional regulator of brown adipogenesis. Moreover, iNOS deletion enhanced the expression of mitochondria-related proteins, such as peroxisome proliferator-activated receptor γ coactivator-1 α (Pgc-1α), sirtuin-1 (Sirt-1) and sirtuin-3 (Sirt-3). Accordingly, mitochondrial uncoupling proteins 1 and 3 (Ucp-1 and Ucp-3) were upregulated in brown adipose tissue (BAT) of DBKO mice as compared to ob/ob rodents. Conclusion Ablation of iNOS improved the energy balance of ob/ob mice by decreasing food efficiency through an increase in thermogenesis. These effects may be mediated, in part, through the recovery of the BAT phenotype and brown fat cell function improvement. PMID:20532036

  12. Contrasting effects of cold acclimation versus obesogenic diets on chemerin gene expression in brown and brite adipose tissues.

    PubMed

    Hansen, Ida R; Jansson, Kim M; Cannon, Barbara; Nedergaard, Jan

    2014-12-01

    Based on results from a signal sequence trap, we investigated chemerin gene expression in brown adipose tissue. Male NMRI mice were exposed to 30, 22 or 4 °C for 3 weeks, or were fed control (chow) diet, cafeteria diet or high-fat diet at thermoneutrality for the same time. In brown adipose tissue, cold acclimation strongly diminished chemerin gene expression, whereas obesogenic diets augmented expression. Qualitatively, changes in expression were paralleled in brite/beige adipose tissues (e.g. inguinal), whereas white adipose tissue (epididymal) and muscle did not react to these cues. Changes in tissue expression were not directly paralleled by alterations in plasma levels. Both these intact animal studies and brown adipocyte cell culture studies indicated that the gene expression regulation was not congruent with a sympathetic/adrenergic control. The data are discussed in relation to suggested endocrine, paracrine and autocrine effects of chemerin.

  13. Age-Related Changes in the Regenerative Potential of Adipose-Derived Stem Cells Isolated from the Prominent Fat Pads in Human Lower Eyelids

    PubMed Central

    Ye, Xinhai; Liao, Caihe; Xu, Yipin; Tan, Jian; Song, Zhenshun

    2016-01-01

    The existence of multipotent adipose-derived stem cells isolated from human orbital fat (OF) tissue has shown great therapeutic potential in tissue engineering and regenerative medicine. But the use of stem cells for therapeutic applications is influenced by their proliferative and differentiation potentials, which may be affected by the age of the donor. So far there is little knowledge about the effects of donor age on the biological properties of human orbital adipose-derived stem cells (OASCs). The intraorbital fat protrusion in the lower eyelids occurs as an aging process, and the protruded fat is routinely removed during aesthetic surgeries. Based on the ease of OF harvest and the availability of OASCs, we investigated in this study the relationship between age and the differentiation and proliferation potentials of human OASCs. Human orbital adipose samples were harvested from young (with normal lower eyelid appearance) and old donors (having protruded fat pads in the lower eyelids). The morphological properties of orbital adipocytes were assessed and the fat cell size displayed a decreasing trend with advancing age. OASCs were isolated from the fat samples, expanded in vitro and cultured under appropriate inducive conditions. Compared to the young cells, although no difference was found in the cell yield and phenotype expression, aged OASCs showed fewer progenitor cell numbers, reduced proliferative rates, increased senescent features and decreased differentiation potentials towards adipogenic, osteogenic and chondrogenic lineages. Our data suggested that using autologous OASCs from elderly patients for potential therapeutic purposes might be restricted. PMID:27855196

  14. High-fat Diet Accelerates Intestinal Tumorigenesis Through Disrupting Intestinal Cell Membrane Integrity

    PubMed Central

    Park, Mi-Young; Kim, Min Young; Seo, Young Rok; Kim, Jong-Sang; Sung, Mi-Kyung

    2016-01-01

    Background: Excess energy supply induces chronic low-grade inflammation in association with oxidative stress in various tissues including intestinal epithelium. The objective of this study was to investigate the effect of high-fat diet (HFD) on intestinal cell membrane integrity and intestinal tumorigenesis in ApcMin/+ mice. Methods: Mice were fed with either normal diet (ND) or HFD for 12 weeks. The number of intestinal tumors were counted and biomarkers of endotoxemia, oxidative stress, and inflammation were determined. Changes in intestinal integrity was measured by fluorescein isothiocyanate (FITC)-dextran penetration and membrane gap junction protein expression. Results: HFD group had significantly higher number of tumors compared to ND group (P < 0.05). Blood total antioxidant capacity was lower in HFD group, while colonic 8-hydroxy-2′-deoxyguanosine level, a marker of oxidative damage, was higher in HFD group compared to that of ND group (P < 0.05). The penetration of FITC-dextran was substantially increased in HFD group (P < 0.05) while the expressions of membrane gap junction proteins including zonula occludens-1, claudin-1, and occludin were lower in HFD group (P < 0.05) compared to those in ND group. Serum concentration of lipopolysaccharide (LPS) receptor (CD14) and colonic toll-like receptor 4 (a LPS receptor) mRNA expression were significantly higher in HFD group than in ND group (P < 0.05), suggesting that significant endotoxemia may occur in HFD group due to the increased membrane permeability. Serum interleukin-6 concentration and myeloperoxidase activity were also higher in HFD group compared to those of ND group (P < 0.05). Conclusions: HFD increases oxidative stress disrupting intestinal gap junction proteins, thereby accelerating membrane permeability endotoxemia, inflammation, and intestinal tumorigenesis. PMID:27390738

  15. Isolation and characterization of mesenchymal stem cells from the fat layer on the density gradient separated bone marrow.

    PubMed

    Insausti, Carmen L; Blanquer, Miguel Blanquer; Olmo, Luis Meseguer; López-Martínez, María C; Ruiz, Xavier Férez; Lozano, Francisco J Rodríguez; Perianes, Valentín Cabañas; Funes, Consuelo; Nicolás, Francisco J; Majado, María J; Jiménez, José M Moraleda

    2012-01-20

    The density gradient centrifugation method was originally designed for the isolation of mononuclear peripheral blood cells and rapidly adapted to fractionate bone marrow (BM) cells. This method involves the use of gradient density solutions with low viscosity and low osmotic pressure that allows erythrocytes and more mature cells gravitate to the bottom at a density fraction superior to 1.080 g/dL; mononuclear cells (MNCs) held in the plasma-solution to interphase at a density between 1.053 and 1.073 g/dL; plasma, dilution medium and anticoagulant to occupy a density less than 1.050 g/dL and the fat cells to float due to their very low density. BM-mesenchymal stem cells (MSCs) are usually obtained after the separation and cultures of BM-MNCs from the plasma-solution interphase, which is traditionally considered the only source of progenitor cells (hematopoietic and nonhematopoietic). In this study evidences that MSCs could be isolated from the very low-density cells of the fat layer are presented. In addition, we demonstrated that the MSCs obtained from these cells have similar immunophenotypic characteristics, and similar proliferative and differentiation potential to those obtained from the MNCs at plasma-solution interphase. The method represents a simple and cost effective way to increase the MSCs yield from each BM donor, without the need to look for other sources, additional manipulation of cells, and risks of contamination or disturbances of the potential of differentiation. These cells might serve as a complementary source of MSCs to facilitate preclinical and clinical application in tissue engineering and cell therapy.

  16. The Impact of Maturity Stage on Cell Membrane Integrity and Enzymatic Browning Reactions in High Pressure Processed Peaches (Prunus persica).

    PubMed

    Techakanon, Chukwan; Gradziel, Thomas M; Zhang, Lu; Barrett, Diane M

    2016-09-28

    Fruit maturity is an important factor associated with final product quality, and it may have an effect on the level of browning in peaches that are high pressure processed (HPP). Peaches from three different maturities, as determined by firmness (M1 = 50-55 N, M2 = 35-40 N, and M3 = 15-20 N), were subjected to pressure levels at 0.1, 200, and 400 MPa for 10 min. The damage from HPP treatment results in loss of fruit integrity and the development of browning during storage. Increasing pressure levels of HPP treatment resulted in greater damage, particularly in the more mature peaches, as determined by shifts in transverse relaxation time (T2) of the vacuolar component and by light microscopy. The discoloration of peach slices of different maturities processed at the same pressure was comparable, indicating that the effect of pressure level is greater than that of maturity in the development of browning.

  17. Brown adipose tissue growth and development.

    PubMed

    Symonds, Michael E

    2013-01-01

    Brown adipose tissue is uniquely able to rapidly produce large amounts of heat through activation of uncoupling protein (UCP) 1. Maximally stimulated brown fat can produce 300 watts/kg of heat compared to 1 watt/kg in all other tissues. UCP1 is only present in small amounts in the fetus and in precocious mammals, such as sheep and humans; it is rapidly activated around the time of birth following the substantial rise in endocrine stimulatory factors. Brown adipose tissue is then lost and/or replaced with white adipose tissue with age but may still contain small depots of beige adipocytes that have the potential to be reactivated. In humans brown adipose tissue is retained into adulthood, retains the capacity to have a significant role in energy balance, and is currently a primary target organ in obesity prevention strategies. Thermogenesis in brown fat humans is environmentally regulated and can be stimulated by cold exposure and diet, responses that may be further modulated by photoperiod. Increased understanding of the primary factors that regulate both the appearance and the disappearance of UCP1 in early life may therefore enable sustainable strategies in order to prevent excess white adipose tissue deposition through the life cycle.

  18. Dedifferentiated Fat Cells as a Novel Source for Cell Therapy to Target Neonatal Hypoxic-Ischemic Encephalopathy.

    PubMed

    Mikrogeorgiou, Alkisti; Sato, Yoshiaki; Kondo, Taiki; Hattori, Tetsuo; Sugiyama, Yuichiro; Ito, Miharu; Saito, Akiko; Nakanishi, Keiko; Tsuji, Masahiro; Kazama, Tomohiko; Kano, Koichiro; Matsumoto, Taro; Hayakawa, Masahiro

    2017-03-09

    Neonatal hypoxic-ischemic (HI) encephalopathy (HIE) remains a major cause of mortality and persistent neurological disabilities in affected individuals. At present, hypothermia is considered to be the only applicable treatment option, although growing evidence suggests that cell-based therapy might achieve better outcomes. Dedifferentiated fat (DFAT) cells are derived from mature adipocytes via a dedifferentiation strategy called ceiling culture. Their abundance and ready availability might make them an ideal therapeutic tool for the treatment of HIE. In the present study, we aimed to determine whether the outcome of HIE can be improved by DFAT cell treatment. HI injury was achieved by ligating the left common carotid artery in 7-day-old rat pups, followed by 1-h exposure to 8% O2. Subsequently, the severity of damage was assessed by diffusion-weighted magnetic resonance imaging to assign animals to equivalent groups. 24 h after hypoxia, DFAT cells were injected at 105 cells/pup into the right external jugular vein. To evaluate brain damage in the acute phase, a group of animals was sacrificed 48 h after the insult, and paraffin sections of the brain were stained to assess several acute injury markers. In the chronic phase, the behavioral outcome was measured by performing a series of behavioral tests. From the 24th day of age, the sensorimotor function was examined by evaluating the initial forepaw placement on a cylinder wall and the latency to falling from a rotarod treadmill. The cognitive function was tested with the novel object recognition (NOR) test. In vitro conditioned medium (CM) prepared from cultured DFAT cells was added at various concentrations to neuronal cell cultures, which were then exposed to oxygen-glucose deprivation (OGD). The number of cells that stained positive for the apoptosis marker active caspase-3 decreased by 73 and 52% in the hippocampus and temporal cortex areas of the brain, respectively, in the DFAT-treated pups. Similarly, the

  19. Functional and anatomical characteristics of the nerve-brown adipose interaction in the rat

    NASA Technical Reports Server (NTRS)

    Flaim, K. E.; Horowitz, J. M.; Horwitz, B. A.

    1976-01-01

    Experiments were conducted on 12 male rats to study the coupling of signals from the sympathetic nervous system to the brown adipose tissue. Analysis of electron photomicrographs revealed considerable morphological heterogeneity among the nerves entering and leaving the interscapular fat pad. In response to electrical simulation of the nerves, the temperature of the brown fat increased following a rapid but transient temperature drop. Such changes were observed only on the ipsilateral side, indicating that the innervation to the interscapular brown fat of the rat is functionally bilateral rather than diffuse. The finding that brown fat is capable of responding in a graded fashion correlates well with observations suggesting that clusters of brown adipocytes may be electrically coupled.

  20. Solid state fermentation of food waste mixtures for single cell protein, aroma volatiles and fat production.

    PubMed

    Aggelopoulos, Theodoros; Katsieris, Konstantinos; Bekatorou, Argyro; Pandey, Ashok; Banat, Ibrahim M; Koutinas, Athanasios A

    2014-02-15

    Growth of selected microorganisms of industrial interest (Saccharomyces cerevisiae, Kluyveromyces marxianus and kefir) by solid state fermentation (SSF) of various food industry waste mixtures was studied. The fermented products were analysed for protein, and nutrient minerals content, as well as for aroma volatile compounds by GC/MS. The substrate fermented by K. marxianus contained the highest sum of fat and protein concentration (59.2% w/w dm) and therefore it could be considered for utilisation of its fat content and for livestock feed enrichment. Regarding volatiles, the formation of high amounts of ε-pinene was observed only in the SSF product of kefir at a yield estimated to be 4 kg/tn of SSF product. A preliminary design of a biorefinery-type process flow sheet and its economic analysis, indicated potential production of products (enriched livestock feed, fat and ε-pinene) of significant added value.

  1. Phenotypic and Functional Properties of Porcine Dedifferentiated Fat Cells during the Long-Term Culture In Vitro.

    PubMed

    Peng, Xuewu; Song, Tongxing; Hu, Xiaoming; Zhou, Yuanfei; Wei, Hongkui; Peng, Jian; Jiang, Siwen

    2015-01-01

    It has been proved that terminally differentiated mature adipocytes possess abilities to dedifferentiate into fibroblast-like progeny cells with self-renewal and multiple differentiation, termed dedifferentiated fat (DFAT) cells. However, the biological properties of DFAT cells during long-term culture in vitro have not been elucidated. Here, we obtained fibroblast-like morphology of porcine DFAT cells by ceiling culture. During the dedifferentiation process, round mature adipocytes with single large lipid droplets changed into spindle-shaped cells accompanied by the adipogenic markers PPARγ, aP2, LPL, and Adiponectin significant downregulation. Flow cytometric analysis showed that porcine DFAT cells displayed similar cell-surface antigen profile to mesenchymal stem cells (MSCs). Furthermore, different passages of porcine DFAT cells during long-term culture in vitro retained high levels of cell viabilities (>97%), efficient proliferative capacity including population doubling time ranged from 20 h to 22 h and population doubling reached 47.40 ± 1.64 by 58 days of culture. In addition, porcine DFAT cells maintained the multiple differentiation capabilities into adipocytes, osteoblasts, and skeletal myocytes and displayed normal chromosomal karyotypes for prolonged passaging. Therefore, porcine DFAT cells may be a novel model of stem cells for studying the functions of gene in the different biological events.

  2. Phenotypic and Functional Properties of Porcine Dedifferentiated Fat Cells during the Long-Term Culture In Vitro

    PubMed Central

    Peng, Xuewu; Song, Tongxing; Hu, Xiaoming; Zhou, Yuanfei; Wei, Hongkui; Peng, Jian; Jiang, Siwen

    2015-01-01

    It has been proved that terminally differentiated mature adipocytes possess abilities to dedifferentiate into fibroblast-like progeny cells with self-renewal and multiple differentiation, termed dedifferentiated fat (DFAT) cells. However, the biological properties of DFAT cells during long-term culture in vitro have not been elucidated. Here, we obtained fibroblast-like morphology of porcine DFAT cells by ceiling culture. During the dedifferentiation process, round mature adipocytes with single large lipid droplets changed into spindle-shaped cells accompanied by the adipogenic markers PPARγ, aP2, LPL, and Adiponectin significant downregulation. Flow cytometric analysis showed that porcine DFAT cells displayed similar cell-surface antigen profile to mesenchymal stem cells (MSCs). Furthermore, different passages of porcine DFAT cells during long-term culture in vitro retained high levels of cell viabilities (>97%), efficient proliferative capacity including population doubling time ranged from 20 h to 22 h and population doubling reached 47.40 ± 1.64 by 58 days of culture. In addition, porcine DFAT cells maintained the multiple differentiation capabilities into adipocytes, osteoblasts, and skeletal myocytes and displayed normal chromosomal karyotypes for prolonged passaging. Therefore, porcine DFAT cells may be a novel model of stem cells for studying the functions of gene in the different biological events. PMID:26090433

  3. Fat-cell mass, serum leptin and adiponectin changes during weight gain and loss in yellow-bellied marmots (Marmota flaviventris).

    PubMed

    Florant, Gregory L; Porst, Heather; Peiffer, Aubrey; Hudachek, Susan F; Pittman, Chris; Summers, Scott A; Rajala, Michael W; Scherer, Philipp E

    2004-11-01

    Leptin and adiponectin are proteins produced and secreted from white adipose tissue and are important regulators of energy balance and insulin sensitivity. Seasonal changes in leptin and adiponectin have not been investigated in mammalian hibernators in relationship to changes in fat cell and fat mass. We sought to determine the relationship between serum leptin and adiponectin levels with seasonal changes in lipid mass. We collected serum and tissue samples from marmots (Marmota flaviventris) in different seasons while measuring changes in fat mass, including fat-cell size. We found that leptin is positively associated with increasing fat mass and fat-cell size, while adiponectin is negatively associated with increasing lipid mass. These findings are consistent with the putative roles of these adipokines: leptin increases with fat mass and is involved in enhancing lipid oxidation while adiponectin appears to be higher in summer when hepatic insulin sensitivity should be maintained since the animals are eating. Our data suggest that during autumn/winter animals have switched from a lipogenic condition to a lipolytic state, which may include leptin resistance.

  4. Contents of soluble, cell-wall-bound and exuded phlorotannins in the brown alga Fucus vesiculosus, with implications on their ecological functions.

    PubMed

    Koivikko, Riitta; Loponen, Jyrki; Honkanen, Tuija; Jormalainen, Veijo

    2005-01-01

    Phlorotannins are ubiquitous secondary metabolites in brown algae that are phenotypically plastic and suggested to have multiple ecological roles. Traditionally, phlorotannins have been quantified as total soluble phlorotannins. Here, we modify a quantification procedure to measure, for the first time, the amount of cell-wall-bound phlorotannins. We also optimize the quantification of soluble phlorotannins. We use these methods to study the responses of soluble and cell-wall-bound phlorotannin to nutrient enrichment in growing and nongrowing parts of the brown alga Fucus vesiculosus. We also examine the effects of nutrient shortage and herbivory on the rate of phlorotannin exudation. Concentrations of cell-wall-bound phlorotannins were much lower than concentrations of soluble phlorotannins; we also found that nutrient treatment over a period of 41 days affected only soluble phlorotannins. Concentrations of each phlorotannin type correlated positively between growing and nongrowing parts of individual seaweeds. However, within nongrowing thalli, soluble and cell-wall-bound phlorotannins were negatively correlated, whereas within growing thalli there was no correlation. Phlorotannins were exuded from the thallus in all treatments. Herbivory increased exudation, while a lack of nutrients had no effect on exudation. Because the amount of cell-wall-bound phlorotannins is much smaller than the amount of soluble phlorotannins, the major function of phlorotannins appears to be a secondary one.

  5. Coconut fats.

    PubMed

    Amarasiri, W A L D; Dissanayake, A S

    2006-06-01

    In many areas of Sri Lanka the coconut tree and its products have for centuries been an integral part of life, and it has come to be called the "Tree of life". However, in the last few decades, the relationship between coconut fats and health has been the subject of much debate and misinformation. Coconut fats account for 80% of the fat intake among Sri Lankans. Around 92% of these fats are saturated fats. This has lead to the belief that coconut fats are 'bad for health', particularly in relation to ischaemic heart disease. Yet most of the saturated fats in coconut are medium chain fatty acids whose properties and metabolism are different to those of animal origin. Medium chain fatty acids do not undergo degradation and re-esterification processes and are directly used in the body to produce energy. They are not as 'bad for health' as saturated fats. There is the need to clarify issues relating to intake of coconut fats and health, more particularly for populations that still depend on coconut fats for much of their fat intake. This paper describes the metabolism of coconut fats and its potential benefits, and attempts to highlight its benefits to remove certain misconceptions regarding its use.

  6. Fat necrosis.

    PubMed

    Canteli, B; Saez, F; de los Ríos, A; Alvarez, C

    1996-04-01

    We report the MR appearance of a case of subcutaneous fat necrosis, which is a previously unreported etiology for knee mass. The role of MR imaging in differentiating fat necrosis from other causes of soft tissue masses is discussed. We conclude that MR characteristics of subcutaneous fat necrosis are typical and allow its differentiation from other types of soft tissue lesions.

  7. HOXC10 suppresses browning of white adipose tissues

    PubMed Central

    Ng, Yvonne; Tan, Shi-Xiong; Chia, Sook Yoong; Tan, Hwee Yim Angeline; Gun, Sin Yee; Sun, Lei; Hong, Wanjin; Han, Weiping

    2017-01-01

    Given that increased thermogenesis in white adipose tissue, also known as browning, promotes energy expenditure, significant efforts have been invested to determine the molecular factors involved in this process. Here we show that HOXC10, a homeobox domain-containing transcription factor expressed in subcutaneous white adipose tissue, is a suppressor of genes involved in browning white adipose tissue. Ectopic expression of HOXC10 in adipocytes suppresses brown fat genes, whereas the depletion of HOXC10 in adipocytes and myoblasts increases the expression of brown fat genes. The protein level of HOXC10 inversely correlates with brown fat genes in subcutaneous white adipose tissue of cold-exposed mice. Expression of HOXC10 in mice suppresses cold-induced browning in subcutaneous white adipose tissue and abolishes the beneficial effect of cold exposure on glucose clearance. HOXC10 exerts its effect, at least in part, by suppressing PRDM16 expression. The results support that HOXC10 is a key negative regulator of the process of browning in white adipose tissue. PMID:28186086

  8. Increased survival of human free fat grafts with varying densities of human adipose-derived stem cells and platelet-rich plasma.

    PubMed

    Li, Kun; Li, Feng; Li, Jie; Wang, Hang; Zheng, Xiaohui; Long, Jie; Guo, Weihua; Tian, Weidong

    2017-01-01

    The high absorption rate of transplanted fat has limited the application of autogenous fat grafts in the clinical setting. Therefore, this study aimed to evaluate the effects of platelet-rich plasma (PRP) and adipose-derived stem cells (ASCs) on fat regeneration by investigating the impact of PRP and conditioned medium on the biological characteristics of ASCs. Fat grafts were prepared with ASCs at densities of 10(7) /ml, 10(6) /ml, 10(5) /ml, 10(4) /ml and 0/ml with and without PRP and injected subcutaneously into nude mice. Liquid overflow method, haematoxylin and eosin staining, and immunohistochemical analyses were used to examine the fat grafts. The residual fat volume of the 10(5) /ml ASC + PRP group was significantly higher than that of other treatment conditions after 90 days. Furthermore, histological examination revealed that in 10(5) /ml ASCs-treated grafts normal adipocyte area and capillary formation were increased dramatically compared with other treatment conditions. It is concluded that fat grafts consisting of PRP and 10(5) /ml ASCs constitute an ideal transplant strategy, which may result in decreased absorption and accelerated fat regeneration. This simple and reliable method could provide a valuable and needed tool in plastic and reconstructive surgery. Copyright © 2014 John Wiley & Sons, Ltd.

  9. Differential signalling pathways for EGF versus PDGF activation of Erk1/2 MAP kinase and cell proliferation in brown pre-adipocytes

    SciTech Connect

    Holmstroem, Therese E.; Mattsson, Charlotte L.; Faelting, Johanna M.; Nedergaard, Jan

    2008-11-15

    Stimulation by both adrenergic and non-adrenergic pathways can induce proliferation of brown pre-adipocytes. To understand the signalling pathways involved in non-adrenergic stimulation of cell proliferation, we examined Erk1/2 activation. In primary cultures of mouse brown pre-adipocytes, both EGF (epidermal growth factor) and PDGF (platelet-derived growth factor) induced Erk1/2 activation. EGF-stimulated Erk1/2 activation involved Src tyrosine kinases, but not PKC or PI3K, whereas in PDGF-induced Erk1/2 activation, PI3K, PKC (probably the atypical {zeta} isoform) and Src were involved sequentially. Both EGF and PDGF induced PI3K-dependent Akt activation that was not involved in Erk1/2 activation. By comparing effects of signalling inhibitors (wortmannin, SH-6, TPA, Goe6983, PP2, PD98059) on EGF- and PDGF-induced Erk1/2 activation and cell proliferation ({sup 3}H-thymidine incorporation), we conclude that while the signal transduction pathways initiated by these growth factors are clearly markedly different, their effects on cell proliferation can be fully explained through their stimulation of Erk1/2 activation; thus Erk1/2 is a common, essential step for stimulation of proliferation in these cells.

  10. Effect of Calorie Restriction With or Without Exercise on Insulin Sensitivity, β-Cell Function, Fat Cell Size, and Ectopic Lipid in Overweight Subjects

    PubMed Central

    Larson-Meyer, D. Enette; Heilbronn, Leonie K.; Redman, Leanne M.; Newcomer, Bradley R.; Frisard, Madlyn I.; Anton, Steve; Smith, Steven R.; Maplstat, Anthony Alfonso; Ravussin, Eric

    2009-01-01

    OBJECTIVE The purpose of this article was to determine the relationships among total body fat, visceral adipose tissue (VAT), fat cell size (FCS), ectopic fat deposition in liver (intra-hepatic lipid [IHL]) and muscle (intramyocellular lipid [IMCL]), and insulin sensitivity index (Si) in healthy overweight, glucose-tolerant subjects and the effects of calorie restriction by diet alone or in conjunction with exercise on these variables. RESEARCH DESIGN AND METHODS Forty-eight overweight volunteers were randomly assigned to four groups: control (100% of energy requirements), 25% calorie restriction (CR), 12.5% calorie restriction +12.5% energy expenditure through structured exercise (CREX), or 15% weight loss by a low-calorie diet followed by weight maintenance for 6 months (LCD). Weight, percent body fat, VAT, IMCL, IHL, FCS, and Si were assessed at baseline and month 6. RESULTS At baseline, FCS was related to VAT and IHL (P < 0.05) but not to IMCL. FCS was also the strongest determinant of Si (P < 0.01). Weight loss at month 6 was 1 ± 1% (control, mean ± SE), 10 ± 1% (CR), 10 ± 1% (CREX), and 14 ± 1% (LCD). VAT, FCS, percent body fat, and IHL were reduced in the three intervention groups (P < 0.01), but IMCL was unchanged. Si was increased at month 6 (P = 0.05) in the CREX (37 ± 18%) and LCD (70 ± 34%) groups (P < 0.05) and tended to increase in the CR group (40 ± 20%, P = 0.08). Together the improvements in Si were related to loss in weight, fat mass, and VAT, but not IHL, IMCL, or FCS. CONCLUSIONS Large adipocytes lead to lipid deposition in visceral and hepatic tissues, promoting insulin resistance. Calorie restriction by diet alone or with exercise reverses this trend. PMID:16732018

  11. Planar cell polarity: the Dachsous/Fat system contributes differently to the embryonic and larval stages of Drosophila

    PubMed Central

    Saavedra, Pedro; Brittle, Amy; Palacios, Isabel M.; Strutt, David; Casal, José; Lawrence, Peter A.

    2016-01-01

    ABSTRACT The epidermal patterns of all three larval instars (L1–L3) of Drosophila are made by one unchanging set of cells. The seven rows of cuticular denticles of all larval stages are consistently planar polarised, some pointing forwards, others backwards. In L1 all the predenticles originate at the back of the cells but, in L2 and L3, they form at the front or the back of the cell depending on the polarity of the forthcoming denticles. We find that, to polarise all rows, the Dachsous/Fat system is differentially utilised; in L1 it is active in the placement of the actin-based predenticles but is not crucial for the final orientation of the cuticular denticles, in L2 and L3 it is needed for placement and polarity. We find Four-jointed to be strongly expressed in the tendon cells and show how this might explain the orientation of all seven rows. Unexpectedly, we find that L3 that lack Dachsous differ from larvae lacking Fat and we present evidence that this is due to differently mislocalised Dachs. We make some progress in understanding how Dachs contributes to phenotypes of wildtype and mutant larvae and adults. PMID:26935392

  12. Mitochondria-targeted dodecyltriphenylphosphonium (C12TPP) combats high-fat-diet-induced obesity in mice

    PubMed Central

    Kalinovich, A V; Mattsson, C L; Youssef, M R; Petrovic, N; Ost, M; Skulachev, V P; Shabalina, I G

    2016-01-01

    Background: A membrane-penetrating cation, dodecyltriphenylphosphonium (C12TPP), facilitates the recycling of fatty acids in the artificial lipid membrane and mitochondria. C12TPP can dissipate mitochondrial membrane potential and may affect total energy expenditure and body weight in animals and humans. Methods: We investigated the metabolic effects of C12TPP in isolated brown-fat mitochondria, brown adipocyte cultures and mice in vivo. Experimental approaches included the measurement of oxygen consumption, carbon dioxide production, western blotting, magnetic resonance imaging and bomb calorimetry. Results: In mice, C12TPP (50 μmol per (day•kg body weight)) in the drinking water significantly reduced body weight (12%, P<0.001) and body fat mass (24%, P<0.001) during the first 7 days of treatment. C12TPP did not affect water palatability and intake or the energy and lipid content in feces. The addition of C12TPP to isolated brown-fat mitochondria resulted in increased oxygen consumption. Three hours of pretreatment with C12TPP also increased oligomycin-insensitive oxygen consumption in brown adipocyte cultures (P<0.01). The effects of C12TPP on mitochondria, cells and mice were independent of uncoupling protein 1 (UCP1). However, C12TPP treatment increased the mitochondrial protein levels in the brown adipose tissue of both wild-type and UCP1-knockout mice. Pair-feeding revealed that one-third of the body weight loss in C12TPP-treated mice was due to reduced food intake. C12TPP treatment elevated the resting metabolic rate (RMR) by up to 18% (P<0.05) compared with pair-fed animals. C12TPP reduced the respiratory exchange ratio, indicating enhanced fatty acid oxidation in mice. Conclusions: C12TPP combats diet-induced obesity by reducing food intake, increasing the RMR and enhancing fatty acid oxidation. PMID:27534841

  13. Juvenile Hormone Differentially Regulates Two Grp78 Genes Encoding Protein Chaperones Required for Insect Fat Body Cell Homeostasis and Vitellogenesis.

    PubMed

    Luo, Maowu; Li, Dong; Wang, Zhiming; Guo, Wei; Kang, Le; Zhou, Shutang

    2017-03-29

    Juvenile hormone (JH) has a well-known role in stimulating insect vitellogenesis (i.e. yolk deposition) and oocyte maturation, but the molecular mechanisms of JH action in insect reproduction are unclear. Glucose-regulated protein of 78 kDa (Grp78) is a heat shock protein 70 kDa family member and one of the most abundant chaperones in the endoplasmic reticulum (ER) where it helps fold newly synthesized peptides. Because of its prominent role in protein folding and also ER stress, we hypothesized that Grp78 might be involved in fat body cell homeostasis and vitellogenesis and a regulatory target of JH. We report here that the migratory locust Locusta migratoria possesses two Grp78 genes that are differentially regulated by JH. We found that Grp78-1 is regulated by JH through Mcm4/7-dependent DNA replication and polyploidization, whereas Grp78-2 expression is directly activated by the JH-receptor complex comprising Methoprene-tolerant and Taiman proteins. Interestingly, Grp78-2 expression in the fat body is about 10-fold higher than that of Grp78-1 Knockdown of either Grp78-1 or Grp78-2 significantly reduced levels of vitellogenin (Vg) protein, accompanied by retarded maturation of oocytes. Depletion of both Grp78-1 and Grp78-2 resulted in ER stress and apoptosis in the fat body and in severely defective Vg synthesis and oocyte maturation. These results indicate a crucial role of Grp78 in JH-dependent vitellogenesis and egg production. The presence and differential regulation of two Grp78 genes in L. migratoria likely help accelerate the production of this chaperone in the fat body to facilitate folding of massively synthesized Vg and other proteins.

  14. Comparison of Markers and Functional Attributes of Human Adipose-Derived Stem Cells and Dedifferentiated Adipocyte Cells from Subcutaneous Fat of an Obese Diabetic Donor

    PubMed Central

    Watson, James E.; Patel, Niketa A.; Carter, Gay; Moor, Andrea; Patel, Rekha; Ghansah, Tomar; Mathur, Abhishek; Murr, Michel M.; Bickford, Paula; Gould, Lisa J.; Cooper, Denise R.

    2014-01-01

    Objective: Adipose tissue is a robust source of adipose-derived stem cells (ADSCs) that may be able to provide secreted factors that promote the ability of wounded tissue to heal. However, adipocytes also have the potential to dedifferentiate in culture to cells with stem cell-like properties that may improve their behavior and functionality for certain applications. Approach: ADSCs are adult mesenchymal stem cells that are cultured from the stromal vascular fraction of adipose tissue. However, adipocytes are capable of dedifferentiating into cells with stem cell properties. In this case study, we compare ADSC and dedifferentiated fat (DFAT) cells from the same patient and fat depot for mesenchymal cell markers, embryonic stem cell markers, ability to differentiate to adipocytes and osteoblasts, senescence and telomerase levels, and ability of conditioned media (CM) to stimulate migration of human dermal fibroblasts (HDFs). Innovation and Conclusions: ADSCs and DFAT cells displayed identical levels of CD90, CD44, CD105, and were CD34- and CD45-negative. They also expressed similar levels of Oct4, BMI1, KLF4, and SALL4. DFAT cells, however, showed higher efficiency in adipogenic and osteogenic capacity. Telomerase levels of DFAT cells were double those of ADSCs, and senescence declined in DFAT cells. CM from both cell types altered the migration of fibroblasts. Despite reports of ADSCs from a number of human depots, there have been no comparisons of the ability of dedifferentiated DFAT cells from the same donor and depot to differentiate or modulate migration of HDFs. Since ADSCs were from an obese diabetic donor, reprogramming of DFAT cells may help improve a patient's cells for regenerative medicine applications. PMID:24669358

  15. Comparison of Markers and Functional Attributes of Human Adipose-Derived Stem Cells and Dedifferentiated Adipocyte Cells from Subcutaneous Fat of an Obese Diabetic Donor.

    PubMed

    Watson, James E; Patel, Niketa A; Carter, Gay; Moor, Andrea; Patel, Rekha; Ghansah, Tomar; Mathur, Abhishek; Murr, Michel M; Bickford, Paula; Gould, Lisa J; Cooper, Denise R

    2014-03-01

    Objective: Adipose tissue is a robust source of adipose-derived stem cells (ADSCs) that may be able to provide secreted factors that promote the ability of wounded tissue to heal. However, adipocytes also have the potential to dedifferentiate in culture to cells with stem cell-like properties that may improve their behavior and functionality for certain applications. Approach: ADSCs are adult mesenchymal stem cells that are cultured from the stromal vascular fraction of adipose tissue. However, adipocytes are capable of dedifferentiating into cells with stem cell properties. In this case study, we compare ADSC and dedifferentiated fat (DFAT) cells from the same patient and fat depot for mesenchymal cell markers, embryonic stem cell markers, ability to differentiate to adipocytes and osteoblasts, senescence and telomerase levels, and ability of conditioned media (CM) to stimulate migration of human dermal fibroblasts (HDFs). Innovation and Conclusions: ADSCs and DFAT cells displayed identical levels of CD90, CD44, CD105, and were CD34- and CD45-negative. They also expressed similar levels of Oct4, BMI1, KLF4, and SALL4. DFAT cells, however, showed higher efficiency in adipogenic and osteogenic capacity. Telomerase levels of DFAT cells were double those of ADSCs, and senescence declined in DFAT cells. CM from both cell types altered the migration of fibroblasts. Despite reports of ADSCs from a number of human depots, there have been no comparisons of the ability of dedifferentiated DFAT cells from the same donor and depot to differentiate or modulate migration of HDFs. Since ADSCs were from an obese diabetic donor, reprogramming of DFAT cells may help improve a patient's cells for regenerative medicine applications.

  16. [Effect of sulfated polysaccharides from brown seaweed Laminaria japonica on the morfology of lymfoid organs and functional characteristics of immunocompetent cells].

    PubMed

    lebedynskaya, E A; Makarenkova, I D; Lebedynskaya, O V; Akhmatova, N K; Zvyagintseva, T N

    2014-01-01

    The effect of sulfated polysaccharide fucoidan from the brown alga Laminaria japonica on morphological characteristics of mouse lymphoid organs, subpopulations of spleen mononuclear leukocytes, cytokine production and cytotoxic activity of splenocytes has been investigated. Fucoidan promoted activation and proliferation of lymphoid hematopoietic cells in primary and secondary immunogenesis bodies, increased expression of markers CD19, NK, NKT, CD25, MHC II, TCR, TLR2 and TLR4, the cytotoxic activity of splenocytes and production of immunoregulatory and proinflammatory cytokines (IL- 2, IL-12, IFN-g, TNF-a, IL-6). This suggests activation of effector mechanisms of innate immunity and adaptive immune responses via the Th-1 type.

  17. Carnitine Palmitoyltransferase 1 Increases Lipolysis, UCP1 Protein Expression and Mitochondrial Activity in Brown Adipocytes

    PubMed Central

    Calderon-Dominguez, María; Sebastián, David; Fucho, Raquel; Weber, Minéia; Mir, Joan F.; García-Casarrubios, Ester; Obregón, María Jesús; Zorzano, Antonio; Valverde, Ángela M.; Serra, Dolors

    2016-01-01

    The discovery of active brown adipose tissue (BAT) in adult humans and the fact that it is reduced in obese and diabetic patients have put a spotlight on this tissue as a key player in obesity-induced metabolic disorders. BAT regulates energy expenditure through thermogenesis; therefore, harnessing its thermogenic fat-burning power is an attractive therapeutic approach. We aimed to enhance BAT thermogenesis by increasing its fatty acid oxidation (FAO) rate. Thus, we expressed carnitine palmitoyltransferase 1AM (CPT1AM), a permanently active mutant form of CPT1A (the rate-limiting enzyme in FAO), in a rat brown adipocyte (rBA) cell line through adenoviral infection. We found that CPT1AM-expressing rBA have increased FAO, lipolysis, UCP1 protein levels and mitochondrial activity. Additionally, enhanced FAO reduced the palmitate-induced increase in triglyceride content and the expression of obese and inflammatory markers. Thus, CPT1AM-expressing rBA had enhanced fat-burning capacity and improved lipid-induced derangements. This indicates that CPT1AM-mediated increase in brown adipocytes FAO may be a new approach to the treatment of obesity-induced disorders. PMID:27438137

  18. Activation of Kupffer Cells Is Associated with a Specific Dysbiosis Induced by Fructose or High Fat Diet in Mice.

    PubMed

    Ferrere, Gladys; Leroux, Anne; Wrzosek, Laura; Puchois, Virginie; Gaudin, Françoise; Ciocan, Dragos; Renoud, Marie-Laure; Naveau, Sylvie; Perlemuter, Gabriel; Cassard, Anne-Marie

    2016-01-01

    The increase consumption of fructose in diet is associated with liver inflammation. As a specific fructan substrate, fructose may modify the gut microbiota which is involved in obesity-induced liver disease. Here, we aimed to assess whether fructose-induced liver damage was associated with a specific dysbiosis, especially in mice fed a high fat diet (HFD). To this end, four groups of mice were fed with normal and HFD added or not with fructose. Body weight and glucose sensitivity, liver inflammation, dysbiosis and the phenotype of Kupffer cells were determined after 16 weeks of diet. Food intake was increased in the two groups of mice fed with the HFD. Mice fed with HFD and fructose showed a higher infiltration of lymphocytes into the liver and a lower inflammatory profile of Kupffer cells than mice fed with the HFD without fructose. The dysbiosis associated with diets showed that fructose specifically prevented the decrease of Mouse intestinal bacteria in HFD fed mice and increased Erysipelotrichi in mice fed with fructose, independently of the amount of fat. In conclusion, fructose, used as a sweetener, induced a dysbiosis which is different in presence of fat in the diet. Consequently, the activation of Kupffer cells involved in mice model of HFD-induced liver inflammation was not observed in an HFD/fructose combined diet. These data highlight that the complexity of diet composition could highly impact the development of liver lesions during obesity. Specific dysbiosis associated with the diet could explain that the progressions of liver damage are different.

  19. Activation of Kupffer Cells Is Associated with a Specific Dysbiosis Induced by Fructose or High Fat Diet in Mice

    PubMed Central

    Ferrere, Gladys; Leroux, Anne; Wrzosek, Laura; Puchois, Virginie; Gaudin, Françoise; Ciocan, Dragos; Renoud, Marie-Laure; Naveau, Sylvie; Perlemuter, Gabriel; Cassard, Anne-Marie

    2016-01-01

    The increase consumption of fructose in diet is associated with liver inflammation. As a specific fructan substrate, fructose may modify the gut microbiota which is involved in obesity-induced liver disease. Here, we aimed to assess whether fructose-induced liver damage was associated with a specific dysbiosis, especially in mice fed a high fat diet (HFD). To this end, four groups of mice were fed with normal and HFD added or not with fructose. Body weight and glucose sensitivity, liver inflammation, dysbiosis and the phenotype of Kupffer cells were determined after 16 weeks of diet. Food intake was increased in the two groups of mice fed with the HFD. Mice fed with HFD and fructose showed a higher infiltration of lymphocytes into the liver and a lower inflammatory profile of Kupffer cells than mice fed with the HFD without fructose. The dysbiosis associated with diets showed that fructose specifically prevented the decrease of Mouse intestinal bacteria in HFD fed mice and increased Erysipelotrichi in mice fed with fructose, independently of the amount of fat. In conclusion, fructose, used as a sweetener, induced a dysbiosis which is different in presence of fat in the diet. Consequently, the activation of Kupffer cells involved in mice model of HFD-induced liver inflammation was not observed in an HFD/fructose combined diet. These data highlight that the complexity of diet composition could highly impact the development of liver lesions during obesity. Specific dysbiosis associated with the diet could explain that the progressions of liver damage are different. PMID:26731543

  20. Mature adipocyte-derived cells, dedifferentiated fat cells (DFAT), promoted functional recovery from spinal cord injury-induced motor dysfunction in rats.

    PubMed

    Ohta, Yuki; Takenaga, Mitsuko; Tokura, Yukie; Hamaguchi, Akemi; Matsumoto, Taro; Kano, Koichiro; Mugishima, Hideo; Okano, Hideyuki; Igarashi, Rie

    2008-01-01

    Transplantation of mature adipocyte-derived cells (dedifferentiated fat cells) led to marked functional recovery from spinal cord injury (SCI)-induced motor dysfunction in rats. When mature adipocytes were isolated from rat adipose tissue and grown in ceiling culture, transformation into fibroblast-like cells without lipid droplets occurred. These fibroblast-like cells, termed dedifferentiated fat cells (DFAT), could proliferate and could also differentiate back into adipocytes. DFAT expressed neural markers such as nestin, betaIII tubulin, and GFAP. Allografting of DFAT into SCI-induced rats led to significant recovery from hindlimb dysfunction. Grafted cells were detected at the injection site, and some of these cells expressed betaIII tubulin. DFAT expressed neurotrophic factors such as BDNF and GDNF prior to transplantation, and grafted cells were also positive for these factors. Therefore, these neurotrophic factors derived from grafted DFAT might have contributed to the promotion of functional recovery. These findings also suggest that mature adipocytes could become a new source for cell replacement therapy to treat central nervous system disorders.

  1. Brown recluse spider

    MedlinePlus

    ... However, they have been found in several large cities outside these areas. The brown recluse spider prefers ... other damp, moist areas. Alternative Names Loxosceles reclusa Images Arthropods, basic features Arachnids, basic features Brown recluse ...

  2. p107 is a crucial regulator for determining the adipocyte lineage fate choices of stem cells.

    PubMed

    De Sousa, Martina; Porras, Deanna P; Perry, Christopher G R; Seale, Patrick; Scimè, Anthony

    2014-05-01

    Thermogenic (beige and brown) adipocytes protect animals against obesity and metabolic disease. However, little is known about the mechanisms that commit stem cells toward different adipocyte lineages. We show here that p107 is a master regulator of adipocyte lineage fates, its suppression required for commitment of stem cells to the brown-type fate. p107 is strictly expressed in the stem cell compartment of white adipose tissue depots and completely absent in brown adipose tissue. Remarkably, p107-deficient stem cells uniformly give rise to brown-type adipocytes in vitro and in vivo. Furthermore, brown fat programming of mesenchymal stem cells by PRDM-BF1-RIZ1 homologous domain containing 16 (Prdm16) was associated with a dramatic reduction of p107 levels. Indeed, Prdm16 directly suppressed p107 transcription via promoter binding. Notably, the sustained expression of p107 blocked the ability of Prdm16 to induce brown fat genes. These findings demonstrate that p107 expression in stem cells commits cells to the white versus brown adipose lineage.

  3. High-fat diet and age-dependent effects on enteric glial cell populations of mouse small intestine.

    PubMed

    Stenkamp-Strahm, Chloe; Patterson, Savannah; Boren, Jennifer; Gericke, Martin; Balemba, Onesmo

    2013-10-01

    Diabetes and obesity are increasing in prevalence at an alarming rate throughout the world. Autonomic diabetic neuropathy is evident in individuals that experience a long-standing diabetic disease state, and gastrointestinal (GI) dysmotility is thought to be the outcome of neuropathies within the enteric nervous system (ENS) of these patients. To date, an analysis of enteric glial cell population changes during diabetic symptoms has not been performed, and may bring insight into disease pathology and neuropathy, given glial cell implications in gastrointestinal and neuronal homeostasis. Diabetes and obesity were monitored in C57Bl/6J mice fed a 72% high-fat diet, and duodenal glial expression patterns were evaluated by immunohistochemistry and RT-PCR for S100β, Sox10 and GFAP proteins and transcripts, as well as transmission electron microscopy (TEM). The high-fat diet caused obesity, hyperglycemia and insulin resistance after 4 weeks. These changes were associated with a significant decline in the area density indices of mucosa-associated glial cell networks, evidenced by S100β staining at 8 and 20 weeks. All three markers and TEM showed that myenteric glial cells were unaffected by early and late disease periods. However, analysis of Sox10 transcript expression and immunoreactivity showed a diet independent, age-associated decline in glial cell populations. This is the first study showing that mucosal glia cell damage occurs during diabetic symptoms, suggesting that mucosal enteric glia injury may have a pathophysiological significance during this disease. Our results also provide support for age-associated changes in longitudinal studies of enteric glial cells.

  4. Significance of brown dwarfs

    NASA Technical Reports Server (NTRS)

    Black, D. C.

    1986-01-01

    The significance of brown dwarfs for resolving some major problems in astronomy is discussed. The importance of brown dwarfs for models of star formation by fragmentation of molecular clouds and for obtaining independent measurements of the ages of stars in binary systems is addressed. The relationship of brown dwarfs to planets is considered.

  5. Osteogenic Effects of Dedifferentiated Fat Cell Transplantation in Rabbit Models of Bone Defect and Ovariectomy-Induced Osteoporosis

    PubMed Central

    Kikuta, Shinsuke; Tanaka, Nobuaki; Kazama, Tomohiko; Kazama, Minako; Kano, Koichiro; Ryu, Junnosuke; Tokuhashi, Yasuaki

    2013-01-01

    We have previously reported that mature adipocyte-derived dedifferentiated fat (DFAT) cells have a high proliferative activity and the potential to differentiate into lineages of mesenchymal tissue similar to bone marrow mesenchymal stem cells (MSCs). In the present study, we examined the effects of autologous DFAT cell transplantation on bone regeneration in a rabbit bone defect model and an ovariectomy (OVX)-induced osteoporosis model. The formation of tissue-engineered bone (TEB) was observed when rabbit DFAT cells were loaded onto a β-tricalcium phosphate (TCP)/collagen sponge and cultured in an osteogenic differentiation medium for 3 weeks. Autologous implantation of DFAT cell-mediated TEB constructs promoted bone regeneration in a rabbit tibial defect model. Regenerated bone tissue induced by transplantation of DFAT cell-mediated TEB constructs was histologically well differentiated and exhibited higher bone strength in a three-point bending test compared to that induced by the β-TCP/collagen sponge alone. In OVX-induced osteoporosis model rabbits, DFAT cells were obtained with the osteogenic activity similar to cells from healthy rabbits. Intrabone marrow injection of autologous DFAT cells significantly increased the bone mineral density (BMD) at the injected site in the OVX rabbits. Transplanted DFAT cells remained mainly on the injection side of the bone marrow by at least 28 days after intrabone marrow injection and a part of them expressed osteocalcin. In conclusion, these results demonstrate that autologous implantation of DFAT cells contributed to bone regeneration in a rabbit bone defect model and an OVX-induced osteoporosis model. DFAT cells may be an attractive cell source for cell-based bone tissue engineering to treat nonunion fractures in all patients, including those with osteoporosis. PMID:23566022

  6. Osteogenic effects of dedifferentiated fat cell transplantation in rabbit models of bone defect and ovariectomy-induced osteoporosis.

    PubMed

    Kikuta, Shinsuke; Tanaka, Nobuaki; Kazama, Tomohiko; Kazama, Minako; Kano, Koichiro; Ryu, Junnosuke; Tokuhashi, Yasuaki; Matsumoto, Taro

    2013-08-01

    We have previously reported that mature adipocyte-derived dedifferentiated fat (DFAT) cells have a high proliferative activity and the potential to differentiate into lineages of mesenchymal tissue similar to bone marrow mesenchymal stem cells (MSCs). In the present study, we examined the effects of autologous DFAT cell transplantation on bone regeneration in a rabbit bone defect model and an ovariectomy (OVX)-induced osteoporosis model. The formation of tissue-engineered bone (TEB) was observed when rabbit DFAT cells were loaded onto a β-tricalcium phosphate (TCP)/collagen sponge and cultured in an osteogenic differentiation medium for 3 weeks. Autologous implantation of DFAT cell-mediated TEB constructs promoted bone regeneration in a rabbit tibial defect model. Regenerated bone tissue induced by transplantation of DFAT cell-mediated TEB constructs was histologically well differentiated and exhibited higher bone strength in a three-point bending test compared to that induced by the β-TCP/collagen sponge alone. In OVX-induced osteoporosis model rabbits, DFAT cells were obtained with the osteogenic activity similar to cells from healthy rabbits. Intrabone marrow injection of autologous DFAT cells significantly increased the bone mineral density (BMD) at the injected site in the OVX rabbits. Transplanted DFAT cells remained mainly on the injection side of the bone marrow by at least 28 days after intrabone marrow injection and a part of them expressed osteocalcin. In conclusion, these results demonstrate that autologous implantation of DFAT cells contributed to bone regeneration in a rabbit bone defect model and an OVX-induced osteoporosis model. DFAT cells may be an attractive cell source for cell-based bone tissue engineering to treat nonunion fractures in all patients, including those with osteoporosis.

  7. Inhibitory effect of rose hip (Rosa canina L.) on melanogenesis in mouse melanoma cells and on pigmentation in brown guinea pigs.

    PubMed

    Fujii, Takashi; Ikeda, Katsumi; Saito, Morio

    2011-01-01

    The compounds present in rose hips exerting an inhibitory action against melanogenesis in B16 mouse melanoma cells were investigated by dividing an aqueous extract of rose hips (RE) into four fractions. The 50% ethanol eluate from a DIAION HP-20 column significantly reduced the production of melanin and was mainly composed of procyanidin glycosides. We also found that this 50% ethanol eluate reduced the intracellular tyrosinase activity and also had a direct inhibitory effect on tyrosinase obtained as a protein mixture from the melanoma cell lysate. We also investigated the effect of orally administering RE on skin pigmentation in brown guinea pigs, and found that the pigmentation was inhibited together with the tyrosinase activity in the skin. These data collectively suggest that proanthocyanidins from RE inhibited melanogenesis in mouse melanoma cells and guinea pig skin, and could be useful as a skin-whitening agent when taken orally.

  8. Rapamycin negatively impacts insulin signaling, glucose uptake and uncoupling protein-1 in brown adipocytes.

    PubMed

    García-Casarrubios, Ester; de Moura, Carlos; Arroba, Ana I; Pescador, Nuria; Calderon-Dominguez, María; Garcia, Laura; Herrero, Laura; Serra, Dolors; Cadenas, Susana; Reis, Flavio; Carvalho, Eugenia; Obregon, Maria Jesus; Valverde, Ángela M

    2016-12-01

    New onset diabetes after transplantation (NODAT) is a metabolic disorder that affects 40% of patients on immunosuppressive agent (IA) treatment, such as rapamycin (also known as sirolimus). IAs negatively modulate insulin action in peripheral tissues including skeletal muscle, liver and white fat. However, the effects of IAs on insulin sensitivity and thermogenesis in brown adipose tissue (BAT) have not been investigated. We have analyzed the impact of rapamycin on insulin signaling, thermogenic gene-expression and mitochondrial respiration in BAT. Treatment of brown adipocytes with rapamycin for 16h significantly decreased insulin receptor substrate 1 (IRS1) protein expression and insulin-mediated protein kinase B (Akt) phosphorylation. Consequently, both insulin-induced glucose transporter 4 (GLUT4) translocation to the plasma membrane and glucose uptake were decreased. Early activation of the N-terminal Janus activated kinase (JNK) was also observed, thereby increasing IRS1 Ser 307 phosphorylation. These effects of rapamycin on insulin signaling in brown adipocytes were partly prevented by a JNK inhibitor. In vivo treatment of rats with rapamycin for three weeks abolished insulin-mediated Akt phosphorylation in BAT. Rapamycin also inhibited norepinephrine (NE)-induced lipolysis, the expression of peroxisome proliferator-activated receptor γ coactivator 1α (PGC-1α) and uncoupling protein (UCP)-1 in brown adipocytes. Importantly, basal mitochondrial respiration, proton leak and maximal respiratory capacity were significantly decreased in brown adipocytes treated with rapamycin. In conclusion, we demonstrate, for the first time the important role of brown adipocytes as target cells of rapamycin, suggesting that insulin resistance in BAT might play a major role in NODAT development.

  9. Application of Green Tea Catechin for Inducing the Osteogenic Differentiation of Human Dedifferentiated Fat Cells in Vitro.

    PubMed

    Kaida, Koji; Honda, Yoshitomo; Hashimoto, Yoshiya; Tanaka, Masahiro; Baba, Shunsuke

    2015-11-25

    Despite advances in stem cell biology, there are few effective techniques to promote the osteogenic differentiation of human primary dedifferentiated fat (DFAT) cells. We attempted to investigate whether epigallocatechin-3-gallate (EGCG), the main component of green tea catechin, facilitates early osteogenic differentiation and mineralization on DFAT cells in vitro. DFAT cells were treated with EGCG (1.25-10 μM) in osteogenic medium (OM) with or without 100 nM dexamethasone (Dex) for 12 days (hereafter two osteogenic media were designated as OM(Dex) and OM). Supplementation of 1.25 μM EGCG to both the media effectively increased the mRNA expression of collagen 1 (COL1A1) and runt-related transcription factor 2 (RUNX2) and also increased proliferation and mineralization. Compared to OM(Dex) with EGCG, OM with EGCG induced earlier expression for COL1A1 and RUNX2 at day 1 and higher mineralization level at day 12. OM(Dex) with 10 μM EGCG remarkably hampered the proliferation of the DFAT cells. These results suggest that OM(without Dex) with EGCG might be a preferable medium to promote proliferation and to induce osteoblast differentiation of DFAT cells. Our findings provide an insight for the combinatory use of EGCG and DFAT cells for bone regeneration and stem cell-based therapy.

  10. Application of Green Tea Catechin for Inducing the Osteogenic Differentiation of Human Dedifferentiated Fat Cells in Vitro

    PubMed Central

    Kaida, Koji; Honda, Yoshitomo; Hashimoto, Yoshiya; Tanaka, Masahiro; Baba, Shunsuke

    2015-01-01

    Despite advances in stem cell biology, there are few effective techniques to promote the osteogenic differentiation of human primary dedifferentiated fat (DFAT) cells. We attempted to investigate whether epigallocatechin-3-gallate (EGCG), the main component of green tea catechin, facilitates early osteogenic differentiation and mineralization on DFAT cells in vitro. DFAT cells were treated with EGCG (1.25–10 μM) in osteogenic medium (OM) with or without 100 nM dexamethasone (Dex) for 12 days (hereafter two osteogenic media were designated as OM(Dex) and OM). Supplementation of 1.25 μM EGCG to both the media effectively increased the mRNA expression of collagen 1 (COL1A1) and runt-related transcription factor 2 (RUNX2) and also increased proliferation and mineralization. Compared to OM(Dex) with EGCG, OM with EGCG induced earlier expression for COL1A1 and RUNX2 at day 1 and higher mineralization level at day 12. OM(Dex) with 10 μM EGCG remarkably hampered the proliferation of the DFAT cells. These results suggest that OM(without Dex) with EGCG might be a preferable medium to promote proliferation and to induce osteoblast differentiation of DFAT cells. Our findings provide an insight for the combinatory use of EGCG and DFAT cells for bone regeneration and stem cell-based therapy. PMID:26602917

  11. The formation of brown adipose tissue induced by transgenic over-expression of PPARγ2.

    PubMed

    Zhou, Ying; Yang, Jinzeng; Huang, Jinliang; Li, Ting; Xu, Dequan; Zuo, Bo; Hou, Liming; Wu, Wangjun; Zhang, Lin; Xia, Xiaoliang; Ma, Zhiyuan; Ren, Zhuqing; Xiong, Yuanzhu

    2014-04-18

    Brown adipose tissue (BAT) is specialized to dissipate energy as heat, therefore reducing fat deposition and counteracting obesity. Brown adipocytes arise from myoblastic progenitors during embryonic development by the action of transcription regulator PRDM16 binding to PPARγ, which promotes BAT-like phenotype in white adipose tissue. To investigate the capability of converting white adipose tissue to BAT or browning by PPARγ in vivo, we generated transgenic mice with over-expressed PPARγ2. The transgenic mice showed strong brown fat features in subcutaneous fat in morphology and histology. To provide molecular evidences on browning characteristics of the adipose tissue, we employed quantitative real-time PCR to determine BAT-specific gene expressions. The transgenic mice had remarkably elevated mRNA level of UCP1, Elovl3, PGC1α and Cebpα in subcutaneous fat. Compared with wild-type mice, UCP1 protein levels were increased significantly in transgenic mice. ATP concentration was slightly decreased in the subcutaneous fat of transgenic mice. Western blotting analysis also confirmed that phosphorylated AMPK and ACC proteins were significantly (P<0.01) increased in the transgenic mice. Therefore, this study demonstrated that over-expression of PPARγ2 in skeletal muscle can promote conversion of subcutaneous fat to brown fat formation, which can have beneficial effects on increasing energy metabolisms and combating obesity.

  12. White, brown and pink adipocytes: the extraordinary plasticity of the adipose organ.

    PubMed

    Giordano, Antonio; Smorlesi, Arianna; Frontini, Andrea; Barbatelli, Giorgio; Cinti, Saverio

    2014-05-01

    In mammals, adipocytes are lipid-laden cells making up the parenchyma of the multi-depot adipose organ. White adipocytes store lipids for release as free fatty acids during fasting periods; brown adipocytes burn glucose and lipids to maintain thermal homeostasis. A third type of adipocyte, the pink adipocyte, has recently been characterised in mouse subcutaneous fat depots during pregnancy and lactation. Pink adipocytes are mammary gland alveolar epithelial cells whose role is to produce and secrete milk. Emerging evidence suggests that they derive from the transdifferentiation of subcutaneous white adipocytes. The functional response of the adipose organ to a range of metabolic and environmental challenges highlights its extraordinary plasticity. Cold exposure induces an increase in the 'brown' component of the organ to meet the increased thermal demand; in states of positive energy balance, the 'white' component expands to store excess nutrients; finally, the 'pink' component develops in subcutaneous depots during pregnancy to ensure litter feeding. At the cell level, plasticity is provided not only by stem cell proliferation and differentiation but also, distinctively, by direct transdifferentiation of fully differentiated adipocytes by the stimuli that induce genetic expression reprogramming and through it a change in phenotype and, consequently function. A greater understanding of adipocyte transdifferentiation mechanisms would have the potential to shed light on their biology as well as inspire novel therapeutic strategies against metabolic syndrome (browning) and breast cancer (pinking).

  13. Phosphorylation at tyrosine 114 of Proliferating Cell Nuclear Antigen (PCNA) is required for adipogenesis in response to high fat diet

    SciTech Connect

    Lo, Yuan-Hung; Ho, Po-Chun; Chen, Min-Shan; Hugo, Eric; Ben-Jonathan, Nira; Wang, Shao-Chun

    2013-01-04

    Highlights: Black-Right-Pointing-Pointer Proliferating Cell Nuclear Antigen (PCNA) is phosphorylated at Y114. Black-Right-Pointing-Pointer Phospho-Y114 of PCNA is not required for cell proliferation for normal growth. Black-Right-Pointing-Pointer MCE during adipogenesis is abolished in the lack of the phosphorylation. Black-Right-Pointing-Pointer Homozygous Y114F mice are resistant to high fat diet induced obesity. Black-Right-Pointing-Pointer Our results shed light on the interface between proliferation and differentiation. -- Abstract: Clonal proliferation is an obligatory component of adipogenesis. Although several cell cycle regulators are known to participate in the transition between pre-adipocyte proliferation and terminal adipocyte differentiation, how the core DNA synthesis machinery is coordinately regulated in adipogenesis remains elusive. PCNA (Proliferating Cell Nuclear Antigen) is an indispensable component for DNA synthesis during proliferation. Here we show that PCNA is subject to phosphorylation at the highly conserved tyrosine residue 114 (Y114). Replacing the Y114 residue with phenylalanine (Y114F), which is structurally similar to tyrosine but cannot be phosphorylated, does not affect normal animal development. However, when challenged with high fat diet, mice carrying homozygous Y114F alleles (PCNA{sup F/F}) are resistant to adipose tissue enlargement in comparison to wild-type (WT) mice. Mouse embryonic fibroblasts (MEFs) harboring WT or Y114F mutant PCNA proliferate at similar rates. However, when subjected to adipogenesis induction in culture, PCNA{sup F/F} MEFs are not able to re-enter the cell cycle and fail to form mature adipocytes, while WT MEFs undergo mitotic clonal expansion in response to the adipogenic stimulation, accompanied by enhanced Y114 phosphorylation of PCNA, and differentiate to mature adipocytes. Consistent with the function of Y114 phosphorylation in clonal proliferation in adipogenesis, fat tissues isolated from WT

  14. Facts about polyunsaturated fats

    MedlinePlus

    Polyunsaturated fatty acid; PUFA; Cholesterol - polyunsaturated fat; Atherosclerosis - polyunsaturated fat; Hardening of the arteries - polyunsaturated fat; Hyperlipidemia - polyunsaturated fat; Hypercholesterolemia - polyunsaturated ...

  15. Comparison of pigment cell ultrastructure and organisation in the dermis of marble trout and brown trout, and first description of erythrophore ultrastructure in salmonids.

    PubMed

    Djurdjevič, Ida; Kreft, Mateja Erdani; Sušnik Bajec, Simona

    2015-11-01

    Skin pigmentation in animals is an important trait with many functions. The present study focused on two closely related salmonid species, marble trout (Salmo marmoratus) and brown trout (S. trutta), which display an uncommon labyrinthine (marble-like) and spot skin pattern, respectively. To determine the role of chromatophore type in the different formation of skin pigment patterns in the two species, the distribution and ultrastructure of chromatophores was examined with light microscopy and transmission electron microscopy. The presence of three types of chromatophores in trout skin was confirmed: melanophores; xanthophores; and iridophores. In addition, using correlative microscopy, erythrophore ultrastructure in salmonids was described for the first time. Two types of erythrophores are distinguished, both located exclusively in the skin of brown trout: type 1 in black spot skin sections similar to xanthophores; and type 2 with a unique ultrastructure, located only in red spot skin sections. Morphologically, the difference between the light and dark pigmentation of trout skin depends primarily on the position and density of melanophores, in the dark region covering other chromatophores, and in the light region with the iridophores and xanthophores usually exposed. With larger amounts of melanophores, absence of xanthophores and presence of erythrophores type 1 and type L iridophores in the black spot compared with the light regions and the presence of erythrophores type 2 in the red spot, a higher level of pigment cell organisation in the skin of brown trout compared with that of marble trout was demonstrated. Even though the skin regions with chromatophores were well defined, not all the chromatophores were in direct contact, either homophilically or heterophilically, with each other. In addition to short-range interactions, an important role of the cellular environment and long-range interactions between chromatophores in promoting adult pigment pattern

  16. The Infrapatellar Fat Pad as a Source of Perivascular Stem Cells with Increased Chondrogenic Potential for Regenerative Medicine.

    PubMed

    Hindle, Paul; Khan, Nusrat; Biant, Leela; Péault, Bruno

    2017-01-01

    Perivascular stem cells (PSCs) are the natural ancestors of mesenchymal stem cells (MSCs) and are the stem cells responsible for homeostasis and repair in vivo. Prospectively identified and isolated PSCs have demonstrated increased plasticity and osteogenic potential. Cells from the infrapatellar fat pad (IFP) have demonstrated increased chondrogenic potential compared with those from subcutaneous fat. This research assessed the chondrogenic potential of IFP PSCs compared with MSCs from the IFP and bone marrow. Immunohistochemistry demonstrated the location of perivascular markers (CD146, CD34, neural/glial antigen 2 [NG2], platelet-derived growth factor receptor-β [PDGFRβ], and α-smooth muscle actin [α-SMA]) in relation to endothelial markers (CD31, CD144, von Willebrand factor [vWF]). Pericytes and adventitial cells were isolated from the stromal vascular fraction (3.8% and 21.2%, respectively) using flow cytometry with a viability of 88%. The mean numbers of pericytes and adventitial cells isolated were 4.6 ± 2.2 × 10(4) and 16.2 ± 3.2 × 10(4) , respectively, equating to 7.9 ± 4.4 × 10(3) and 20.8 ± 4.3 × 10(3) cells per gram of harvested tissue. Fluorescence-activated cell sorting demonstrated that cultured PSCs were CD44+CD90+CD105+; polymerase chain reaction and immunocytochemistry demonstrated that pericytes retained their CD146+ phenotype and expressed the pericyte markers PDGFRβ and NG2. Differentiation was confirmed using histochemical stains and genetic expression. Using a pellet model, the IFP PSCs and the MSCs generated significantly more extracellular matrix than bone marrow MSCs (p < .001 and p = .011, respectively). The IFP PSCs generated significantly more extracellular matrix than IFP MSCs (p = .002). Micromass culture demonstrated that differentiated PSCs were upregulated compared with MSCs for COL2A1, ACAN, and SOX9 expression by factors of 4.8 ± 1.3, 4.3 ± 0.9, and 7.0 ± 1.7, respectively. The IFP was a significantly better

  17. Dietary Fats

    MedlinePlus

    ... PHOs to food. Try to replace them with oils such as canola, olive, safflower, sesame, or sunflower. Of course, eating too much fat will put on the pounds. Fat has twice as many calories as proteins or carbohydrates. NIH: National Heart, Lung, and Blood Institute

  18. Wound Healing Immediately Post-Thermal Injury Is Improved by Fat and Adipose Derived Stem Cell Isografts

    PubMed Central

    Loder, Shawn; Peterson, Jonathan R.; Agarwal, Shailesh; Eboda, Oluwatobi; Brownley, Cameron; DeLaRosa, Sara; Ranganathan, Kavitha; Cederna, Paul; Wang, Stewart C.; Levi, Benjamin

    2014-01-01

    Objectives Patients with severe burns suffer functional, structural, and aesthetic complications. It is important to explore reconstructive options given that no ideal treatment exists. Transfer of adipose and adipose-derived stem cells (ASCs) has been shown to improve healing in various models. We hypothesize that use of fat isografts and/or ASCs will improve healing in a mouse model of burn injury. Methods Twenty 6–8 week old C57BL/6 male mice received a 30% surface area partial-thickness scald burn. Adipose tissue and ASCs from inguinal fat pads were harvested from a second group of C57BL/6 mice. Burned mice received 500μl subcutaneous injection at burn site of 1) processed adipose, 2) ASCs, 3) mixed adipose (adipose and ASCs), or 4) sham (saline) injection (n=5/group) on the first day post-injury. Mice were followed by serial photography until sacrifice at days 5 and 14. Wounds were assessed for burn depth and healing by Hematoxylin and Eosin (H&E) and immunohistochemistry. Results All treated groups showed improved healing over controls defined by decreased wound depth, area, and apoptotic activity. After 5 days, mice receiving ASCs or mixed adipose displayed a non-significant improvement in vascularization. No significant changes in proliferation were noted at 5 days. Conclusions Adipose isografts improve some early markers of healing post-burn injury. We demonstrate that addition of these grafts improve specific structural markers of healing. This improvement may be due to an increase in early wound vascularity post-graft. Further studies are needed to optimize use of fat or ASC grafts in acute and reconstructive surgery. PMID:25185931

  19. Homeostatic response to blocking cell division in Drosophila imaginal discs: Role of the Fat/Dachsous (Ft/Ds) pathway.

    PubMed

    Montes, Antonio J; Morata, Ginés

    2017-03-11

    One major problem in developmental biology is the identification of the mechanisms that control the final size of tissues and organs. We are addressing this issue in the imaginal discs of Drosophila by analysing the response to blocking cell division in large domains in the wing and leg discs. The affected domains may be zones of restricted lineage like compartments, or zones of open lineage that may integrate cells from the surrounding territory. Our results reveal the existence of a powerful homeostatic mechanism that can compensate for gross differences in growth rates and builds structures of normal size. This mechanism functions at the level of whole discs, inducing additional cell proliferation to generate the cells that populate the cell division-arrested territory and generating an active recruitment process to integrate those cells. The activation of this response mechanism is mediated by alterations in the normal activity of PCP genes of the Fat/Ds system: in discs mutant for dachs, ds or four jointed the response mechanism is not activated.

  20. High fat diet increases melanoma cell growth in the bone marrow by inducing osteopontin and interleukin 6

    PubMed Central

    Chen, Guang-Liang; Luo, Yubin; Eriksson, Daniel; Meng, Xianyi; Qian, Cheng; Bäuerle, Tobias; Chen, Xiao-Xiang; Schett, Georg; Bozec, Aline

    2016-01-01

    The impact of metabolic stress induced by obesity on the bone marrow melanoma niche is largely unknown. Here we employed diet induced obese mice model, where mice received high-fat (HFD) or normal diet (ND) for 6 weeks before challenge with B16F10 melanoma cells. Tumor size, bone loss and osteoclasts numbers were assessed histologically in the tibial bones. For defining the molecular pathway, osteopontin knock-out mice, interleukin 6 neutralizing antibody or Janus kinase 2 inhibition were carried out in the same model. Mechanistic studies such as adipocyte-melanoma co-cultures for defining adipocyte induced changes of tumor cell proliferation and expression profiles were also performed. As results, HFD enhanced melanoma burden in bone by increasing tumor area and osteoclast numbers. This process was associated with higher numbers of bone marrow adipocytes expressing IL-6 in direct vicinity to tumor cells. Inhibition of IL-6 or of downstream JAK2 blocked HFD-induced tumor progression. Furthermore, the phenotypic changes of melanoma cells triggered macrophage and osteoclast accumulation accompanied by increased osteopontin expression. Osteopontin triggered osteoclastogenesis and also exerted a positive feedback loop to tumor cells, which was abrogated in its absence. Metabolic stress by HFD promotes melanoma growth in the bone marrow by an increase in bone marrow adipocytes and IL-6-JAK2-osteopontin mediated activation of tumor cells and osteoclast differentiation. PMID:27049717

  1. Characterisation of synovial fluid and infrapatellar fat pad derived mesenchymal stromal cells: The influence of tissue source and inflammatory stimulus

    PubMed Central

    Garcia, John; Wright, Karina; Roberts, Sally; Kuiper, Jan Herman; Mangham, Chas; Richardson, James; Mennan, Claire

    2016-01-01

    The infrapatellar fat pad (FP) and synovial fluid (SF) in the knee serve as reservoirs of mesenchymal stromal cells (MSCs) with potential therapeutic benefit. We determined the influence of the donor on the phenotype of donor matched FP and SF derived MSCs and examined their immunogenic and immunomodulatory properties before and after stimulation with the pro-inflammatory cytokine interferon-gamma (IFN-γ). Both cell populations were positive for MSC markers CD73, CD90 and CD105, and displayed multipotency. FP-MSCs had a significantly faster proliferation rate than SF-MSCs. CD14 positivity was seen in both FP-MSCs and SF-MSCs, and was positively correlated to donor age but only for SF-MSCs. Neither cell population was positive for the co-stimulatory markers CD40, CD80 and CD86, but both demonstrated increased levels of human leukocyte antigen-DR (HLA-DR) following IFN-γ stimulation. HLA-DR production was positively correlated with donor age for FP-MSCs but not SF-MSCs. The immunomodulatory molecule, HLA-G, was constitutively produced by both cell populations, unlike indoleamine 2, 3-dioxygenase which was only produced following IFN-γ stimulation. FP and SF are accessible cell sources which could be utilised in the treatment of cartilage injuries, either by transplantation following ex-vivo expansion or endogenous targeting and mobilisation of cells close to the site of injury. PMID:27073003

  2. Parallel Profiles of Inflammatory and Effector Memory T Cells in Visceral Fat and Liver of Obesity-Associated Cancer Patients.

    PubMed

    Conroy, Melissa J; Galvin, Karen C; Doyle, Suzanne L; Kavanagh, Maria E; Mongan, Ann-Marie; Cannon, Aoife; Moore, Gillian Y; Reynolds, John V; Lysaght, Joanne

    2016-10-01

    In the midst of a worsening obesity epidemic, the incidence of obesity-associated morbidities, including cancer, diabetes, cardiac and liver disease is increasing. Insights into mechanisms underlying pathological obesity-associated inflammation are lacking. Both the omentum, the principal component of visceral fat, and liver of obese individuals are sites of excessive inflammation, but to date the T cell profiles of both compartments have not been assessed or compared in a patient cohort with obesity-associated disease. We have previously identified that omentum is enriched with inflammatory cytokines, chemokines and T cells. Here, we compared the inflammatory profile of T cells in the omentum and liver of patients with the obesity-associated malignancy oesophageal adenocarcinoma (OAC). Furthermore, we assessed the secreted cytokine profile in OAC patient serum, omentum and liver to assess systemic and local inflammation. We observed parallel T cell cytokine profiles and phenotypes in the omentum and liver of OAC patients, in particular CD69(+) and inflammatory effector memory T cells. This study reflects similar processes of inflammation and T cell activation in the omentum and liver, and may suggest common targets to modulate pathological inflammation at these sites.

  3. Human brown adipose tissue: regulation and anti-obesity potential.

    PubMed

    Saito, Masayuki

    2014-01-01

    Brown adipose tissue (BAT) is the site of sympathetically activated adaptive thermognenesis during cold exposure and after hyperphagia, thereby controlling whole-body energy expenditure (EE) and body fat. Radionuclide imaging studies have demonstrated that adult humans have metabolically active BAT composed of mainly beige/brite adipocytes, recently identified brown-like adipocytes. The inverse relationship between the BAT activity and body fatness suggests that BAT is, because of its energy dissipating activity, protective against body fat accumulation in humans as it is in small rodents. In fact, either repeated cold exposure or daily ingestion of some food ingredients acting on transient receptor potential channels recruits BAT in parallel with increased EE and decreased body fat. In addition to the sympathetic nervous system, several endocrine factors are also shown to recruit BAT. Thus, BAT is a promising therapeutic target for combating human obesity and related metabolic disorders.

  4. The Infrapatellar Fat Pad as a Source of Perivascular Stem Cells With Increased Chondrogenic Potential for Regenerative Medicine.

    PubMed

    Hindle, Paul; Khan, Nusrat; Biant, Leela; Péault, Bruno

    2016-08-05

    : Perivascular stem cells (PSCs) are the natural ancestors of mesenchymal stem cells (MSCs) and are the stem cells responsible for homeostasis and repair in vivo. Prospectively identified and isolated PSCs have demonstrated increased plasticity and osteogenic potential. Cells from the infrapatellar fat pad (IFP) have demonstrated increased chondrogenic potential compared with those from subcutaneous fat. This research assessed the chondrogenic potential of IFP PSCs compared with MSCs from the IFP and bone marrow. Immunohistochemistry demonstrated the location of perivascular markers (CD146, CD34, neural/glial antigen 2 [NG2], platelet-derived growth factor receptor-β [PDGFRβ], and α-smooth muscle actin [α-SMA]) in relation to endothelial markers (CD31, CD144, von Willebrand factor [vWF]). Pericytes and adventitial cells were isolated from the stromal vascular fraction (3.8% and 21.2%, respectively) using flow cytometry with a viability of 88%. The mean numbers of pericytes and adventitial cells isolated were 4.6 ± 2.2 × 10(4) and 16.2 ± 3.2 × 10(4), respectively, equating to 7.9 ± 4.4 × 10(3) and 20.8 ± 4.3 × 10(3) cells per gram of harvested tissue. Fluorescence-activated cell sorting demonstrated that cultured PSCs were CD44+CD90+CD105+; polymerase chain reaction and immunocytochemistry demonstrated that pericytes retained their CD146+ phenotype and expressed the pericyte markers PDGFRβ and NG2. Differentiation was confirmed using histochemical stains and genetic expression. Using a pellet model, the IFP PSCs and the MSCs generated significantly more extracellular matrix than bone marrow MSCs (p < .001 and p = .011, respectively). The IFP PSCs generated significantly more extracellular matrix than IFP MSCs (p = .002). Micromass culture demonstrated that differentiated PSCs were upregulated compared with MSCs for COL2A1, ACAN, and SOX9 expression by factors of 4.8 ± 1.3, 4.3 ± 0.9, and 7.0 ± 1.7, respectively. The IFP was a significantly better

  5. Expanded Stem Cells, Stromal-Vascular Fraction, and Platelet-Rich Plasma Enriched Fat: Comparing Results of Different Facial Rejuvenation Approaches in a Clinical Trial

    PubMed Central

    Rigotti, Gino; Charles-de-Sá, Luiz; Gontijo-de-Amorim, Natale Ferreira; Takiya, Christina Maeda; Amable, Paola Romina; Borojevic, Radovan; Benati, Donatella; Bernardi, Paolo; Sbarbati, Andrea

    2016-01-01

    Background In a previous study, the authors demonstrated that treatment with expanded adipose-derived stem cells or stromal vascular fraction (SVF)-enriched fat modify the pattern of the dermis in human beings, representing a skin rejuvenation effect. Considering that expanded stem cells require a cell factor, the authors wanted to assess similar results by replacing them with platelet-rich plasma (PRP), which is easier to obtain and for which an empirical regenerative effect has been already described. Objectives To determine if PRP injection could replace the cutaneous regenerative effect of adipose-derived stem cells. Methods This study was performed in 13 patients who were candidates for facelift. The patients underwent sampling of fat by liposuction from the abdomen and submitted to one of three protocols: injection of SVF-enriched fat or expanded adipose-derived stem cells or fat plus PRP in the preauricular areas. Fragments of skin were removed before and 3 months after treatment and analyzed by optical and electron microscopy. Results The use of fat plus PRP led to the presence of more pronounced inflammatory infiltrates and a greater vascular reactivity, increasing in vascular permeability and a certain reactivity of the nervous component. The addition of PRP did not improve the regenerative effect. Conclusion The use of PRP did not have significant advantages in skin rejuvenation over the use of expanded adipose-derived stem cells or SVF-enriched fat. The effect of increased vascular reactivity may be useful in pathological situations in which an intense angiogenesis is desirable, such as tissular ischemia. Level of Evidence: 4 Therapeutic PMID:26879294

  6. Ghrelin receptor controls obesity by fat burning

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Emerging evidence show that brown fat in the body produces heat to burn energy, thus prompting weight loss. Ghrelin is the only known hormone which increases appetite and promotes weight gain. We have reported that mice that lack the receptor which mediates the functions of ghrelin are lean. Our fu...

  7. Fermented Brown Rice and Rice Bran with Aspergillus oryzae (FBRA) Prevents Inflammation-Related Carcinogenesis in Mice, through Inhibition of Inflammatory Cell Infiltration

    PubMed Central

    Onuma, Kunishige; Kanda, Yusuke; Suzuki Ikeda, Saori; Sakaki, Ryuta; Nonomura, Takuya; Kobayashi, Masanobu; Osaki, Mitsuhiko; Shikanai, Masataka; Kobayashi, Hiroshi; Okada, Futoshi

    2015-01-01

    We have established an inflammation-related carcinogenesis model in mouse, in which regressive QR-32 cells subcutaneously co-implanted with a foreign body—gelatin sponge—convert themselves into lethal tumors due to massive infiltration of inflammatory cells into the sponge. Animals were fed with a diet containing 5% or 10% fermented brown rice and rice bran with Aspergillus oryzae (FBRA). In 5% and 10% FBRA diet groups, tumor incidences were lower (35% and 20%, respectively) than in the non-treated group (70%). We found that FBRA reduced the number of inflammatory cells infiltrating into the sponge. FBRA administration did not cause myelosuppression, which indicated that the anti-inflammatory effects of FBRA took place at the inflammatory lesion. FBRA did not have antitumor effects on the implanted QRsP-11 tumor cells, which is a tumorigenic cell line established from a tumor arisen after co-implantation of QR-32 cells with sponge. FBRA did not reduce formation of 8-hydroxy-2′-deoxyguanine adducts, a marker of oxidative DNA damage in the inflammatory lesion; however, it reduced expression of inflammation-related genes such as TNF-α, Mac-1, CCL3 and CXCL2. These results suggest that FBRA will be an effective chemopreventive agent against inflammation-related carcinogenesis that acts by inhibiting inflammatory cell infiltration into inflammatory lesions. PMID:26670250

  8. Generation and Characterization of Eptesicus fuscus (Big brown bat) kidney cell lines immortalized using the Myotis polyomavirus large T-antigen.

    PubMed

    Banerjee, Arinjay; Rapin, Noreen; Miller, Megan; Griebel, Philip; Zhou, Yan; Munster, Vincent; Misra, Vikram

    2016-11-01

    It is speculated that bats are important reservoir hosts for numerous viruses, with 27 viral families reportedly detected in bats. Majority of these viruses have not been isolated and there is little information regarding their biology in bats. Establishing a well-characterized bat cell line supporting the replication of bat-borne viruses would facilitate the analysis of virus-host interactions in an in vitro model. Currently, few bat cell lines have been developed and only Tb1-Lu, derived from Tadarida brasiliensis is commercially available. Here we describe a method to establish and immortalize big brown bat (Eptesicus fuscus) kidney (Efk3) cells using the Myotis polyomavirus T-antigen. Subclones of this cell line expressed both epithelial and fibroblast markers to varying extents. Cell clones expressed interferon beta in response to poly(I:C) stimulation and supported the replication of four different viruses, namely, vesicular stomatitis virus (VSV), porcine epidemic diarrhea coronavirus (PED-CoV), Middle-East respiratory syndrome coronavirus (MERS-CoV) and herpes simplex virus (HSV). To our knowledge, this is the first bat cell line from a northern latitude insectivorous bat developed using a novel technology. The cell line has the potential to be used for isolation of bat viruses and for studying virus-bat interactions in culture.

  9. Fucose-containing sulfated polysaccharides from brown seaweeds inhibit proliferation of melanoma cells and induce apoptosis by activation of caspase-3 in vitro.

    PubMed

    Ale, Marcel Tutor; Maruyama, Hiroko; Tamauchi, Hidekazu; Mikkelsen, Jørn D; Meyer, Anne S

    2011-12-01

    Fucose-containing sulfated polysaccharides (FCSPs) extracted from seaweeds, especially brown macro-algae, are known to possess essential bioactive properties, notably growth inhibitory effects on tumor cells. In this work, we conducted a series of in vitro studies to examine the influence of FCSPs products from Sargassumhenslowianum C. Agardh (FSAR) and Fucus vesiculosus (FVES), respectively, on proliferation of melanoma B16 cells and to investigate the underlying apoptosis promoting mechanisms. Cell viability analysis showed that both FCSPs products, i.e., FSAR and FVES, decreased the proliferation of the melanoma cells in a dose-response fashion, with FSAR being more potent at lower dosages, and FVES being relatively more anti-proliferative than FSAR at higher dosages. Flow cytometric analysis by Annexin V staining of the melanoma cells exposed to the FCSPs products confirmed that both FSAR and FVES induced apoptosis. The FCSPs-induced apoptosis was evidenced by loss of plasma membrane asymmetry and translocation of the cell membrane phospholipids and was accompanied by the activation of caspase-3. The FCSPs bioactivity is proposed to be attributable to distinct structural features of the FCSPs, particularly the presence of sulfated galactofucans (notably in S.henslowianum) and sulfated fucans (notably in F. vesiculosus). This study thus indicates that unfractionated FCSPs may exert bioactive effects on skin cancer cells via induction of apoptosis through cascades of reactions that involve activation of caspase-3.

  10. Visceral fat area is a strong predictor of leukocyte cell-derived chemotaxin 2, a potential biomarker of dyslipidemia

    PubMed Central

    Tanisawa, Kumpei; Taniguchi, Hirokazu; Sun, Xiaomin; Ito, Tomoko; Kawakami, Ryoko; Sakamoto, Shizuo; Higuchi, Mitsuru

    2017-01-01

    Background Leukocyte cell-derived chemotaxin 2 (LECT2) is a hepatokine linking obesity to skeletal muscle insulin resistance. Although previous studies reported that obesity was associated with high levels of circulating LECT2 in human, the associations of detailed body fat distribution with LECT2 levels have not been examined. Furthermore, although animal study suggested that exercise decreased circulating LECT2 levels, it remains unknown whether physical fitness is associated with LECT2 levels in human. We therefore examined the relationship of plasma LECT2 levels with various adiposity indices and cardiorespiratory fitness (CRF) in middle-aged and elderly Japanese men. Furthermore, we examined the relationship of LECT2 levels with the presence of metabolic syndrome, hypertension, insulin resistance and dyslipidemia to determine the clinical significance of measuring circulating LECT2. Materials and methods This was a cross-sectional study of 143 Japanese men (age: 30–79 years). Participants’ plasma LECT2 levels were measured by an enzyme-linked immunosorbent assay. To assess their abdominal fat distributions, visceral fat area (VFA) and subcutaneous fat area (SFA) were measured using magnetic resonance imaging. CRF was assessed by measuring peak oxygen uptake (V˙O2peak). Results All adiposity indices measured in this study were positively correlated with plasma LECT2 levels, while V˙O2peak was negatively correlated with LECT2 levels after adjustment for age. The correlations, except for VFA were no longer significant with further adjustment for VFA. Stepwise multiple linear regression analysis revealed that VFA was the strongest predictor of plasma LECT2 levels. Plasma LECT2 levels differed based on the presence of metabolic syndrome and dyslipidemia, but not hypertension and insulin resistance. Logistic regression analyses revealed that plasma LECT2 levels were significantly associated with dyslipidemia independently of VFA; VFA was not significantly

  11. White-to-brown metabolic conversion of human adipocytes by JAK inhibition

    PubMed Central

    Moisan, Annie; Lee, Youn-Kyoung; Zhang, Jitao David; Hudak, Carolyn S.; Meyer, Claas A.; Prummer, Michael; Zoffmann, Sannah; Truong, Hoa Hue; Ebeling, Martin; Kiialainen, Anna; Gérard, Régine; Xia, Fang; Schinzel, Robert T.; Amrein, Kurt E.; Cowan, Chad A.

    2014-01-01

    The rising incidence of obesity and related disorders such as diabetes and heart disease has focused considerable attention on the discovery of novel therapeutics. One promising approach has been to increase the number or activity of brown-like adipocytes in white adipose depots, as this has been shown to prevent diet-induced obesity and reduce the incidence and severity of type 2 diabetes. Thus, the conversion of fat-storing cells into metabolically active thermogenic cells has become an appealing therapeutic strategy to combat obesity. Here, we report a screening platform for the identification of small molecules capable of promoting a white-to-brown metabolic conversion in human adipocytes. We identified two inhibitors of Janus Kinase (JAK) activity with no precedent in adipose tissue biology that stably confer brown-like metabolic activity to white adipocytes. Importantly, these metabolically converted adipocytes exhibit elevated UCP1 expression and increased mitochondrial activity. We further found that repression of interferon signalling and activation of hedgehog signalling in JAK-inactivated adipocytes contributes to the metabolic conversion observed in these cells. Our findings highlight a novel role for the JAK/STAT pathway in the control of adipocyte function and establish a platform to identify compounds for the treatment of obesity. PMID:25487280

  12. Phosphorylation at tyrosine 114 of Proliferating Cell Nuclear Antigen (PCNA) is required for adipogenesis in response to high fat diet.

    PubMed

    Lo, Yuan-Hung; Ho, Po-Chun; Chen, Min-Shan; Hugo, Eric; Ben-Jonathan, Nira; Wang, Shao-Chun

    2013-01-04

    Clonal proliferation is an obligatory component of adipogenesis. Although several cell cycle regulators are known to participate in the transition between pre-adipocyte proliferation and terminal adipocyte differentiation, how the core DNA synthesis machinery is coordinately regulated in adipogenesis remains elusive. PCNA (Proliferating Cell Nuclear Antigen) is an indispensable component for DNA synthesis during proliferation. Here we show that PCNA is subject to phosphorylation at the highly conserved tyrosine residue 114 (Y114). Replacing the Y114 residue with phenylalanine (Y114F), which is structurally similar to tyrosine but cannot be phosphorylated, does not affect normal animal development. However, when challenged with high fat diet, mice carrying homozygous Y114F alleles (PCNA(F/F)) are resistant to adipose tissue enlargement in comparison to wild-type (WT) mice. Mouse embryonic fibroblasts (MEFs) harboring WT or Y114F mutant PCNA proliferate at similar rates. However, when subjected to adipogenesis induction in culture, PCNA(F/F) MEFs are not able to re-enter the cell cycle and fail to form mature adipocytes, while WT MEFs undergo mitotic clonal expansion in response to the adipogenic stimulation, accompanied by enhanced Y114 phosphorylation of PCNA, and differentiate to mature adipocytes. Consistent with the function of Y114 phosphorylation in clonal proliferation in adipogenesis, fat tissues isolated from WT mice contain significantly more adipocytes than those isolated from PCNA(F/F) mice. This study identifies a critical role for PCNA in adipose tissue development, and for the first time identifies a role of the core DNA replication machinery at the interface between proliferation and differentiation.

  13. Co-stimulation with bone morphogenetic protein-9 and FK506 induces remarkable osteoblastic differentiation in rat dedifferentiated fat cells.

    PubMed

    Nakamura, Toshiaki; Shinohara, Yukiya; Momozaki, Sawako; Yoshimoto, Takehiko; Noguchi, Kazuyuki

    2013-10-18

    Dedifferentiated fat (DFAT) cells, which are isolated from mature adipocytes using the ceiling culture method, exhibit similar characteristics to mesenchymal stem cells, and possess adipogenic, osteogenic, chondrogenic, and myogenic potentials. Bone morphogenetic protein (BMP)-2 and -9, members of the transforming growth factor-β superfamily, exhibit the most potent osteogenic activity of this growth factor family. However, the effects of BMP-2 and BMP-9 on the osteogenic differentiation of DFAT remain unknown. Here, we examined the effects of BMP-2 and BMP-9 on osteoblastic differentiation of rat DFAT (rDFAT) cells in the presence or absence of FK506, an immunosuppressive agent. Co-stimulation with BMP-9 and FK506 induced gene expression of runx2, osterix, and bone sialoprotein, and ALP activity compared with BMP-9 alone, BMP-2 alone and BMP-2+FK506 in rDFAT cells. Furthermore, it caused mineralization of cultures and phosphorylation of smad1/5/8, compared with BMP-9 alone. The ALP activity induced by BMP-9+FK506 was not influenced by addition of noggin, a BMP antagonist. Our data suggest that the combination of BMP-9 and FK506 potently induces osteoblastic differentiation of rDFAT cells.

  14. UCP1 inhibition in Cidea-overexpressing mice is physiologically counteracted by brown adipose tissue hyperrecruitment.

    PubMed

    Fischer, Alexander W; Shabalina, Irina G; Mattsson, Charlotte L; Abreu-Vieira, Gustavo; Cannon, Barbara; Nedergaard, Jan; Petrovic, Natasa

    2017-01-01

    Cidea is a gene highly expressed in thermogenesis-competent (UCP1-containing) adipose cells, both brown and brite/beige. Here, we initially demonstrate a remarkable adipose-depot specific regulation of Cidea expression. In classical brown fat, Cidea mRNA is expressed continuously and invariably, irrespective of tissue recruitment. However, Cidea protein levels are regulated posttranscriptionally, being conspicuously induced in the thermogenically recruited state. In contrast, in brite fat, Cidea protein levels are regulated at the transcriptional level, and Cidea mRNA and protein levels are proportional to tissue "briteness." Although routinely followed as a thermogenic molecular marker, Cidea function is not clarified. Here, we employed a gain-of-function approach to examine a possible role of Cidea in the regulation of thermogenesis. We utilized transgenic aP2-hCidea mice that overexpress human Cidea in all adipose tissues. We demonstrate that UCP1 activity is markedly suppressed in brown-fat mitochondria isolated from aP2-hCidea mice. However, mitochondrial UCP1 protein levels were identical in wild-type and transgenic mice. This implies a regulatory effect of Cidea on UCP1 activity, but as we demonstrate that Cidea itself is not localized to mitochondria, we propose an indirect inhibitory effect. The Cidea-induced inhibition of UCP1 activity (observed in isolated mitochondria) is physiologically relevant since the mice, through an appropriate homeostatic compensatory mechanism, increased the total amount of UCP1 in the tissue to exactly match the diminished thermogenic capacity of the UCP1 protein and retain unaltered nonshivering thermogenic capacity. Thus, we verified Cidea as being a marker of thermogenesis-competent adipose tissues, but we conclude that Cidea, unexpectedly, functions molecularly as an indirect inhibitor of thermogenesis.

  15. Role of Receptor-Interacting Protein 140 in human fat cells

    PubMed Central

    2010-01-01

    Background Mice lacking Receptor-interacting protein 140 (RIP140) have reduced body fat which at least partly is mediated through increased lipid and glucose metabolism in adipose tissue. In humans, RIP140 is lower expressed in visceral white adipose tissue (WAT) of obese versus lean subjects. We investigated the role of RIP140 in human subcutaneous WAT, which is the major fat depot of the body. Methods Messenger RNA levels of RIP140 were measured in samples of subcutaneous WAT from women with a wide variation in BMI and in different human WAT preparations. RIP140 mRNA was knocked down with siRNA in in vitro differentiated adipocytes and the impact on glucose transport and mRNA levels of target genes determined. Results RIP140 mRNA levels in subcutaneous WAT were decreased among obese compared to lean women and increased by weight-loss, but did not associate with mitochondrial DNA copy number. RIP140 expression increased during adipocyte differentiation in vitro and was higher in isolated adipocytes compared to corresponding pieces of WAT. Knock down of RIP140 increased basal glucose transport and mRNA levels of glucose transporter 4 and uncoupling protein-1. Conclusions Human RIP140 inhibits glucose uptake and the expression of genes promoting energy expenditure in the same fashion as the murine orthologue. Increased levels of human RIP140 in subcutaneous WAT of lean subjects may contribute to economize on energy stores. By contrast, the function and expression pattern does not support that RIP140 regulate human obesity. PMID:20205832

  16. Dihydroxyacetone, the active browning ingredient in sunless tanning lotions, induces DNA damage, cell-cycle block and apoptosis in cultured HaCaT keratinocytes.

    PubMed

    Petersen, Anita B; Wulf, Hans Christian; Gniadecki, Robert; Gajkowska, Barbara

    2004-06-13

    Dihydroxyacetone (DHA), the active substance in sunless tanning lotions reacts with the amino groups of proteins to form a brown-colored complex. This non-enzymatic glycation, known as the Maillard reaction, can also occur with free amino groups in DNA, raising the possibility that DHA may be genotoxic. To address this issue we investigated the effects of DHA on cell survival and proliferation of a human keratinocyte cell line, HaCaT. Dose- and time-dependent morphological changes, chromatin condensation, cytoplasmic budding and cell detachment were seen in cells treated with DHA. Several dead cells were observed after long-time (24 h) incubation with 25 mM DHA or more. Furthermore, an extensive decline in proliferation was observed 1 day after DHA exposure for 24 h. When applied in different concentrations (5-50 mM) and for different time periods (1, 3 or 24 h) DHA caused a G(2)/M block after the cyclin B(1) restriction point. Exit from this cell-cycle block was associated with massive apoptosis, as revealed by a clonogenic assay, TUNEL staining and electron microscopy. Furthermore, DHA caused DNA damage as revealed by the alkaline comet assay. Preincubation with antioxidants prevented the formation of DNA strand breaks. The DHA toxicity may be caused by direct redox reactions, with formation of ROS as the crucial intermediates. The genotoxic capacity of DHA raises a question about the long-term clinical consequences of treatment of the skin with this commonly used compound.

  17. Brown recluse spider envenomation.

    PubMed

    Furbee, R Brent; Kao, Louise W; Ibrahim, Danyal

    2006-03-01

    Brown recluse spider bite is a common diagnosis in almost every state in America. In fact, cases have been reported in areas where the spider has never been seen. A review of medical literature reveals that most current concepts regarding brown recluse spider envenomation are based on supposition. In this article, we attempt to review critically our present understanding of brown recluse bites with a focus on the published evidence.

  18. Ontogenetic changes in retinal ganglion cell distribution and spatial resolving power in the brown-banded bamboo shark Chiloscyllium punctatum (Elasmobranchii).

    PubMed

    Harahush, Blake K; Hart, Nathan S; Collin, Shaun P

    2014-01-01

    The development of the visual system in anamniotic vertebrates is a continual process, allowing for ontogenetic changes in retinal topography and spatial resolving power. We examined the number and distribution of retinal ganglion cells in wholemounted retinae throughout the protracted embryonic development (∼5 months) of a chondrichthyan, i.e. the brown-banded bamboo shark Chiloscyllium punctatum, from the beginning of retinal cell differentiation (approximately halfway through embryogenesis) to adulthood. We also identified and quantified the number of apoptosed cells within the ganglion cell layer to evaluate the contribution of apoptosis to changes in retinal topography. C. punctatum undergoes rapid changes in ganglion cell distribution during embryogenesis, where high levels of apoptosis, especially around the retinal periphery, result in relative increases in ganglion cell density in the central retina which progressively extend nasally and temporally to form a meridional band at hatching. After hatching, C. punctatum forms and maintains a horizontal streak, showing only minor changes in topography during growth, with basal levels of apoptosis. The total number of retinal ganglion cells reaches 547,881 in adult sharks, but the mean (3,228 cells·mm(-2)) and peak (4,983 cells·mm(-2)) retinal ganglion cell densities are highest around the time of hatching. Calculated estimates of spatial resolving power, based on ganglion cell spacing (assuming a hexagonal mosaic) and assessment of the focal length from cryosections of the eye, increase from 1.47 cycles·degree(-1) during embryogenesis to 4.29 cycles·degree(-1) in adults. The increase in spatial resolving power across the retinal meridian would allow this species to hunt and track faster, more mobile prey as it reaches maturity.

  19. High-fat diet exacerbates inflammation and cell survival signals in the skin of ultraviolet B-irradiated C57BL/6 mice

    SciTech Connect

    Meeran, Syed M.; Singh, Tripti; Nagy, Tim R.; Katiyar, Santosh K.

    2009-12-15

    Inflammation induced by chronic exposure to ultraviolet (UV) radiation has been implicated in various skin diseases. We formulated the hypothesis that a high-fat diet may influence the UV-induced inflammatory responses in the skin. C57BL/6 mice were fed a high-fat diet or control diet and exposed to UVB radiation (120 mJ/cm{sup 2}) three times/week for 10 weeks. The mice were then sacrificed and skin and plasma samples collected for analysis of biomarkers of inflammatory responses using immunohistochemistry, western blotting, ELISA and real-time PCR. We found that the levels of inflammatory biomarkers were increased in the UVB-exposed skin of the mice fed the high-fat diet than the UVB-exposed skin of the mice fed the control diet. The levels of inflammatory biomarkers of early responses to UVB exposure (e.g., myeloperoxidase, cyclooxygenase-2, prostaglandin-E{sub 2}), proinflammatory cytokines (i.e., tumor necrosis factor-alpha, interleukin-1beta, interleukin-6), and proliferating cell nuclear antigen and cell survival signals (phosphatidylinositol-3-kinase and p-Akt-Ser{sup 473}) were higher in high-fat-diet-fed mouse skin than control-diet-fed mouse skin. The plasma levels of insulin growth factor-1 were greater in the UVB-irradiated mice fed the high-fat diet than the UVB-irradiated mice fed the control diet, whereas the levels of plasma adiponectin were significantly lower. This pronounced exacerbation of the UVB-induced inflammatory responses in the skin of mice fed a high-fat diet suggests that high-fat diet may increase susceptibility to inflammation-associated skin diseases, including the risk of skin cancer.

  20. Growth Inhibitory Effect of Low Fat Diet on Prostate Cancer Cells: Results of a Prospective, Randomized Dietary Intervention Trial in Men With Prostate Cancer

    PubMed Central

    Aronson, William J.; Barnard, R. James; Freedland, Stephen J.; Henning, Susanne; Elashoff, David; Jardack, Patricia M.; Cohen, Pinchas; Heber, David; Kobayashi, Naoko

    2011-01-01

    Purpose A high fat Western diet and sedentary lifestyle may predispose men to prostate cancer through changes in serum hormones and growth factors. We evaluated the effect of a low fat diet on serum factors affecting prostate cancer cell growth by performing a prospective, randomized dietary intervention trial in men with prostate cancer. Materials and Methods We randomized 18 men with prostate cancer who did not receive prior therapy to a low fat (15% kcal), high fiber, soy protein supplemented diet or a Western (40% kcal fat) diet for 4 weeks. Fasting serum was collected at baseline and after the intervention to measure prostate specific antigen, sex hormones, insulin, insulin-like growth factor I and II, insulin-like growth factor binding proteins, lipids and fatty acids. LNCaP cells (ATCC®) were cultured in medium containing pre-intervention and post-intervention human serum to assess the in vitro effect of the diet on prostate cancer cell proliferation. Results Subjects in each group were highly compliant with the dietary intervention. Serum from men in the low fat group significantly decreased the growth of LNCaP cells relative to Western diet serum (p = 0.03). There were no significant between group changes in serum prostate specific antigen, sex hormones, insulin, insulin-like growth factor I and II, and insulin-like growth factor binding proteins. Serum triglyceride and linoleic acid (ω-6) levels were decreased in the low fat group (p = 0.034 and 0.005, respectively). Correlation analysis revealed that decreased ω-6 and increased ω-3 fatty acid correlated with decreased serum stimulated LNCaP cell growth (r = 0.64, p = 0.004 and r = −0.49, p = 0.04, respectively). Conclusions In this prospective, randomized dietary intervention trial a low fat diet resulted in changes in serum fatty acid levels that were associated with decreased human LNCaP cancer cell growth. Further prospective trials are indicated to evaluate the potential of low fat diets for

  1. [Indirect coculture of human infrapatellar fat pad-derived stem cells with osteoarthritic chondrocytes induces their chondrogenesis].

    PubMed

    Yang, Junjun; Chen, Cheng; Yang, Liu; Song, Xiongbo; Xie, Wenbin; Huang, Shu; Liu, Baorong

    2017-02-01

    Objective To promote phenotype recovery of osteoarthritic articular chondrocytes (OACs) and induce chondrogenic differentiation of infrapatellar fat pad-derived stem cells (IPFPSCs) by indirectly coculturing these two types of cells. Methods The OACs and IPFPSCs were isolated and cultured in vitro. This experiment included single IPFPSCs group, single OACs group, and coculture group. After cells were cultured in vitro with chondrogenic medium for 21 days, the chondrocyte phenotypes were determined by HE staining (cell morphology), Alcian blue staining (glycosaminoglycan content) and immunofluorescence cytochemistry (collagen 1, collagen 2, collagen 3, aggrecan, SOX9). Results In coculture group, the OACs aggregated into microspheres, and the IPFPSCs were oval in shape. In single culture groups, the OACs were less aggregated and the spheres were smaller; and the IPFPSCs were spindle in shape. HE staining showed that, in the coculture group, the nuclei of OACs spheres were dark, and the IPFPSCs were rich in cytoplasm; while in single culture groups, the nuclei of OAC spheres were less dark, and the IPFPSCs were less stained compared with the coculture group. Alcian blue staining indicated that glycosaminoglycan content was higher in the coculture group than in single culture groups. Immunofluorescent staining showed that the intensity of chondrogenic markers (collagen 2, aggrecan, and SOX9) was stronger, while the intensity of collagen 1 and collagen 10 was weaker in the coculture group as compared with single culture groups. Conclusion The indirect coculture of IPFPSCs with OACs can contribute to the phenotype recovery of OACs and induce the chondrogenic differentiation of IPFPSCs.

  2. Analyzing Serum-Stimulated Prostate Cancer Cell Lines After Low-Fat, High-Fiber Diet and Exercise Intervention

    PubMed Central

    Soliman, Sherry; Aronson, William J.; Barnard, R. James

    2011-01-01

    Serum from men undergoing a low-fat, high-fiber diet and exercise intervention has previously been shown to decrease growth and increase apoptosis in serum-stimulated, androgen-dependent LNCaP cells associated with a reduction in serum IGF-I. Here we sought to determine the underlying mechanisms for these anticancer effects. Again, the intervention slowed growth and increased apoptosis in LNCaP cells; responses that were eliminated when IGF-I was added back to the post-intervention samples. The p53 protein content was increased and NFκB activation reduced in the post serum-stimulated LNCaP cells. Similar results were observed when the IGF-I receptor was blocked in the pre-intervention serum. In androgen-independent PC-3 cells, growth was reduced while none of the other factors were changed by the intervention. We conclude that diet and exercise intervention might help prevent clinical PCa as well as aid in the treatment of PCa during the early stages of development. PMID:19376839

  3. Adipose tissue can be generated in vitro by using adipocytes from human fat tissue mesenchymal stem cells seeded and cultured on fibrin gel sheet.

    PubMed

    Tran, Cong Toai; Huynh, Duy Thao; Gargiulo, Ciro; Tran, Le Bao Ha; Huynh, Minh Hang; Nguyen, Khanh Hoa; Filgueira, Luis; Strong, D Micheal

    2013-03-01

    The current study has developed an innovative procedure to generate ex novo fat tissue by culturing adipocytes from human fat tissue mesenchymal stem cells (hFTMSCs) on fibrin gel sheet towards applications in medicine and cosmetology. Fibrin gel has been obtained by combining two components fibrinogen and thrombin collected by human peripheral blood. By this procedure it was possible to generate blocks of fibrin gel containing adipocytes within the gel that show similar features and consistency to human fat tissue mass. Results were assessed by histological staining methods, fluorescent immune-histochemistry staining as well photos by scanning electron microscopy (SEM) to demonstrate the adhesion and growth of cells in the fibrin gel. This result opens a real possibility for future clinical applications in the treatment of reconstructive and regenerative medicine where the use of stem cell may eventually be a unique solution or in the field of aesthetic medicine where autograft fat stem cells may grant for a safer and better outcome with long lasting results.

  4. Enhancement of Adipocyte Browning by Angiotensin II Type 1 Receptor Blockade

    PubMed Central

    Tsukuda, Kana; Mogi, Masaki; Iwanami, Jun; Kanno, Harumi; Nakaoka, Hirotomo; Wang, Xiao-Li; Bai, Hui-Yu; Shan, Bao-Shuai; Kukida, Masayoshi; Higaki, Akinori; Yamauchi, Toshifumi; Min, Li-Juan; Horiuchi, Masatsugu

    2016-01-01

    Browning of white adipose tissue (WAT) has been highlighted as a new possible therapeutic target for obesity, diabetes and lipid metabolic disorders, because WAT browning could increase energy expenditure and reduce adiposity. The new clusters of adipocytes that emerge with WAT browning have been named ‘beige’ or ‘brite’ adipocytes. Recent reports have indicated that the renin-angiotensin system (RAS) plays a role in various aspects of adipose tissue physiology and dysfunction. The biological effects of angiotensin II, a major component of RAS, are mediated by two receptor subtypes, angiotensin II type 1 receptor (AT1R) and type 2 receptor (AT2R). However, the functional roles of angiotensin II receptor subtypes in WAT browning have not been defined. Therefore, we examined whether deletion of angiotensin II receptor subtypes (AT1aR and AT2R) may affect white-to-beige fat conversion in vivo. AT1a receptor knockout (AT1aKO) mice exhibited increased appearance of multilocular lipid droplets and upregulation of thermogenic gene expression in inguinal white adipose tissue (iWAT) compared to wild-type (WT) mice. AT2 receptor-deleted mice did not show miniaturization of lipid droplets or alteration of thermogenic gene expression levels in iWAT. An in vitro experiment using adipose tissue-derived stem cells showed that deletion of the AT1a receptor resulted in suppression of adipocyte differentiation, with reduction in expression of thermogenic genes. These results indicate that deletion of the AT1a receptor might have some effects on the process of browning of WAT and that blockade of the AT1 receptor could be a therapeutic target for the treatment of metabolic disorders. PMID:27992452

  5. Autophagy in the fat body cells of the cave cricket Troglophilus neglectus Krauss, 1878 (Rhaphidophoridae, Saltatoria) during overwintering.

    PubMed

    Lipovšek, Saška; Novak, Tone

    2016-03-01

    The cave cricket Troglophilus neglectus regularly overwinters for 4-5 months in hypogean habitats. Winter dormancy is a natural starvation period, providing the opportunity to study autophagy under natural conditions. We aimed to evaluate the autophagic activity in adipocytes and urocytes of the fat body in three time frames: directly before overwintering, in the middle of dormancy, and at its end. For this purpose, we sampled individuals in caves. The cell ultrastructure was studied by transmission electron microscopy (TEM) and the abundance of autophagosomes by immunofluorescence microscopy (IFM), applying the widely used, specific immunolabeling marker microtubule-associated protein 1 light chain 3 (LC3). Before overwintering, TEM revealed scarce autophagosomes and residual bodies in the adipocytes and none in the urocytes. Congruently, IFM showed a very limited or no reaction. In the middle and at the end of overwintering, in both cell types, phagophores, autophagosomes, autolysosomes, and residual bodies were identified by TEM, while LC3 immunolabeling for detecting autophagosomes showed a conspicuous positive reaction. Both methods revealed that there were no significant differences between the sexes in any time frame. Minimal autophagic activity was detected before the winter dormancy, and it gradually intensified till the end of overwintering, probably because reserve proteins in protein granula are not composed of all the required amino acids. We conclude that in T. neglectus, autophagy is a substantial response to starvation and supports homeostatic processes during winter dormancy by supplying cells with nutrients.

  6. Inhibitory effect of N-adamantyl-3,4-dihydroxybenzamide on melanogenesis in melan-a cells and brown guinea pigs.

    PubMed

    Rho, Ho Sik; Ahn, Soo Mi; Hwang, Jae Sung

    2011-04-01

    To find novel depigmenting agents, a new synthetic compound, N-adamantyl-3,4-dihydroxybenzamide (NADB) was produced and the effects on melanogenesis were investigated. Our results showed that NADB reduced melanin synthesis in a dose-dependent manner in melan-a cells. Tyrosinase activity was also reduced by NADB treatment in melan-a cells. However, NADB did not inhibit tyrosinase activity directly in a cell-free system. Treatment of melan-a cells with NADB caused a marked decrease in protein and mRNA levels of tyrosinase along with tyrosinase-related protein 1 and dopachrome tautomerase. To determine whether NADB reduces skin pigmentation, the dorsal skin of brown guinea pigs was shaved and irradiated with UV for 3 weeks using a solar simulator. Then NADB (2 or 1% in propylene glycol:ethanol:water = 5:3:2) was applied topically twice daily for 4 weeks. Visual inspection and Fontana-Masson staining both demonstrated that NADB resulted in lower skin pigmentation and total epidermal melanin in comparison to vehicle-treated areas. These findings suggest that NADB is useful in the treatment of hyperpigmentation.

  7. Carbon nanotube-based substrates promote cardiogenesis in brown adipose-derived stem cells via β1-integrin-dependent TGF-β1 signaling pathway

    PubMed Central

    Sun, Hongyu; Mou, Yongchao; Li, Yi; Li, Xia; Chen, Zi; Duval, Kayla; Huang, Zhu; Dai, Ruiwu; Tang, Lijun; Tian, Fuzhou

    2016-01-01

    Stem cell-based therapy remains one of the promising approaches for cardiac repair and regeneration. However, its applications are restricted by the limited efficacy of cardiac differentiation. To address this issue, we examined whether carbon nanotubes (CNTs) would provide an instructive extracellular microenvironment to facilitate cardiogenesis in brown adipose-derived stem cells (BASCs) and to elucidate the underlying signaling pathways. In this study, we systematically investigated a series of cellular responses of BASCs due to the incorporation of CNTs into collagen (CNT-Col) substrates that promoted cell adhesion, spreading, and growth. Moreover, we found that CNT-Col substrates remarkably improved the efficiency of BASCs cardiogenesis by using fluorescence staining and quantitative real-time reverse transcription-polymerase chain reaction. Critically, CNTs in the substrates accelerated the maturation of BASCs-derived cardiomyocytes. Furthermore, the underlying mechanism for promotion of BASCs cardiac differentiation by CNTs was determined by immunostaining, quantitative real-time reverse transcription-polymerase chain reaction, and Western blotting assay. It is notable that β1-integrin-dependent TGF-β1 signaling pathway modulates the facilitative effect of CNTs in cardiac differentiation of BASCs. Therefore, it is an efficient approach to regulate cardiac differentiation of BASCs by the incorporation of CNTs into the native matrix. Importantly, our findings can not only facilitate the mechanistic understanding of molecular events initiating cardiac differentiation in stem cells, but also offer a potentially safer source for cardiac regenerative medicine. PMID:27660434

  8. Cell suspension culture of Eriobotrya japonica regulates the diabetic and hyperlipidemic signs of high-fat-fed mice.

    PubMed

    Shih, Chun-Ching; Ciou, Jiun-Lin; Lin, Cheng-Hsiu; Wu, Jin-Bin; Ho, Hui-Ya

    2013-03-01

    The present study investigates the anti-hyperlipidemic and antihyperglycemic effects and mechanism in high-fat (HF)-fed mice of cell suspension culture of Eriobotrya japonica (TA), which contains a great number of pentacyclic terpenoids. Firstly, C57BL/6J mice were randomly divided into two groups: the control (CON) group was fed with a low-fat diet (n = 9), whereas the experimental group was fed a 45% HF diet for 8 weeks. Afterwards, the CON group was treated with vehicle, whereas the HF group was subdivided into five groups and was orally given TA or rosiglitazone or not for 4 weeks. Blood and visceral adipose tissue, liver tissue and skeletal muscle were examined. Treatment with TA reduced body weight gain, weights of white adipose tissue (WAT) (including epididymal, perirenal, mesenteric WAT and visceral fat), and hepatic triacylglycerol content significantly without affecting food intake in diet-induced diabetic mice. TA effectively prevented HF diet-induced increases in the levels of blood glucose, insulin, leptin and HOMA-IR index (p < 0.001, p < 0.05, p < 0.05, p < 0.01, respectively) and attenuated insulin resistance. Treatment with TA, adipocytes in the visceral depots showed a reduction in size. TA effectively significantly increased the protein contents of phosphorylation of AMPK-α (Thr172) both in liver and adipose tissue. It is shown that TA exhibits hypolipidemic effect in HF-fed mice by decreasing gene expressions of fatty acid synthesis, including acyl-coenzyme A: diacylglycerol acyltransferase (DGAT) 2, which catalyzes the final step in the synthesis of triglycerides, and antidiabetic properties occurred as a result of decreased hepatic glucose production via phosphenolpyruvate carboxykinase (PEPCK) down- regulation, improved insulin sensitization and TA (at 1.0 g/kg dose) decreased expression of hepatic and adipose 11-β-hydroxysteroid dehydroxygenase (11β-HSD1) gene, which contributed in attenuating diabetic state. Futhermore, TA at doses of 0

  9. Short-term high-fat diet alters postprandial glucose metabolism and circulating vascular cell adhesion molecule-1 in healthy males.

    PubMed

    Numao, Shigeharu; Kawano, Hiroshi; Endo, Naoya; Yamada, Yuka; Takahashi, Masaki; Konishi, Masayuki; Sakamoto, Shizuo

    2016-08-01

    Short-term intake of a high-fat diet aggravates postprandial glucose metabolism; however, the dose-response relationship has not been investigated. We hypothesized that short-term intake of a eucaloric low-carbohydrate/high-fat diet (LCHF) would aggravate postprandial glucose metabolism and circulating adhesion molecules in healthy males. Seven healthy young males (mean ± SE; age: 26 ± 1 years) consumed either a eucaloric control diet (C, approximately 25% fats), a eucaloric intermediate-carbohydrate/intermediate-fat diet (ICIF, approximately 50% fats), or an LCHF (approximately 70% fats) for 3 days. An oral meal tolerance test (MTT) was performed after the 3-day dietary intervention. The concentrations of plasma glucose, insulin, glucagon-like peptide-1 (GLP-1), intercellular adhesion molecule-1, and vascular cell adhesion molecule-1 (VCAM-1) were determined at rest and during MTT. The incremental area under the curve (iAUC) of plasma glucose concentration during MTT was significantly higher in LCHF than in C (P = 0.009). The first-phase insulin secretion indexes were significantly lower in LCHF than in C (P = 0.04). Moreover, the iAUC of GLP-1 and VCAM-1 concentrations was significantly higher in LCHF than in C (P = 0.014 and P = 0.04, respectively). The metabolites from ICIF and C were not significantly different. In conclusion, short-term intake of eucaloric diet containing a high percentage of fats in healthy males excessively increased postprandial glucose and VCAM-1 concentrations and attenuated first-phase insulin release.

  10. Regulation of lipid synthesis genes and milk fat production in human mammary epithelial cells during secretory activation.

    PubMed

    Mohammad, Mahmoud A; Haymond, Morey W

    2013-09-15

    Expression of genes for lipid biosynthetic enzymes during initiation of lactation in humans is unknown. Our goal was to study mRNA expression of lipid metabolic enzymes in human mammary epithelial cell (MEC) in conjunction with the measurement of milk fatty acid (FA) composition during secretory activation. Gene expression from mRNA isolated from milk fat globule (MFG) and milk FA composition were measured from 6 h to 42 days postpartum in seven normal women. Over the first 96 h postpartum, daily milk fat output increased severalfold and mirrored expression of genes for all aspects of lipid metabolism and milk FA production, including lipolysis at the MEC membrane, FA uptake from blood, intracellular FA transport, de novo FA synthesis, FA and glycerol activation, FA elongation, FA desaturation, triglyceride synthesis, cholesterol synthesis, and lipid droplet formation. Expression of the gene for a key lipid synthesis regulator, sterol regulatory element-binding transcription factor 1 (SREBF1), increased 2.0-fold by 36 h and remained elevated over the study duration. Expression of genes for estrogen receptor 1, thyroid hormone-responsive protein, and insulin-induced 2 increased progressively to plateau by 96 h. In contrast, mRNA of peroxisome proliferator-activated receptor-γ decreased severalfold. With onset of lactation, increased de novo synthesis of FA was the most prominent change in milk FA composition and mirrored the expression of FA synthesis genes. In conclusion, milk lipid synthesis and secretion in humans is a complex process requiring the orchestration of a wide variety of pathways of which SREBF1 may play a primary role.

  11. Protective effect of berberine on beta cells in streptozotocin- and high-carbohydrate/high-fat diet-induced diabetic rats.

    PubMed

    Zhou, Jiyin; Zhou, Shiwen; Tang, Jianlin; Zhang, Kebin; Guang, Lixia; Huang, Yongping; Xu, Ying; Ying, Yi; Zhang, Le; Li, Dandan

    2009-03-15

    Oxidative stress in diabetes coexists with a reduction in the antioxidant status, which can further increase the deleterious effects of free radicals. Berberine is one of the main alkaloids of Rhizoma coptidis which has been used to treat diabetes for more than 1400 years in China. The present study was designed to evaluate the protective effects of berberine against beta cell damage and antioxidant of pancreas in diabetic rats. Diabetic rats with hyperlipidemia were induced by intraperitoneally injection 35 mg/kg streptozotocin and a high-carbohydrate/high-fat diet. Rats were divided into 7 groups at the end of week 16: untreated control, untreated diabetic, 75, 150, 300 mg/kg berberine-treated diabetic, 100 mg/kg fenofibrate-treated, and 4 mg/kg rosiglitazone-treated. After 16 weeks treatment, serum insulin level, insulin expression in pancreas, and malonaldehyde content, superoxide dismutase activity in pancreatic homogenate were assayed. Pancreas was examined by hematoxylin/eosin staining and transmission electron microscope. Pancreas to body weight ratio, insulin level, insulin sensitivity index, malonaldehyde content and superoxide dismutase activity were altered in diabetic rats, and were near control levels treated with 150, 300 mg/kg berberine. Mitochondrial vacuolization and swelling, dilatation of the endoplasmic reticulum were observed in beta cells of diabetic rats. The pancreatic islet area atrophied and secretory granules of beta cells decreased in diabetic rats. Slight pathological changes existed in beta cells of 150, 300 mg/kg berberine-treated diabetic pancreas. These findings suggest that berberine has protective effect for diabetes through increasing insulin expression, beta cell regeneration, antioxidant enzyme activity and decreasing lipid peroxidation.

  12. Myocardial Ischemic Subject’s Thymus Fat: A Novel Source of Multipotent Stromal Cells

    PubMed Central

    Salas, Julián; Lhamyani, Said; Gentile, Adriana-Mariel; Sarria García, Esteban; Hmadcha, Abdelkrim; Zayed, Hatem; Vega-Rioja, Antonio; Tinahones, Francisco J.; El Bekay, Rajaa

    2015-01-01

    Objective Adipose Tissue Stromal Cells (ASCs) have important clinical applications in the regenerative medicine, cell replacement and gene therapies. Subcutaneous Adipose Tissue (SAT) is the most common source of these cells. The adult human thymus degenerates into adipose tissue (TAT). However, it has never been studied before as a source of stem cells. Material and Methods We performed a comparative characterization of TAT-ASCs and SAT-ASCs from myocardial ischemic subjects (n = 32) according to the age of the subjects. Results TAT-ASCs and SAT-ASCs showed similar features regarding their adherence, morphology and in their capacity to form CFU-F. Moreover, they have the capacity to differentiate into osteocyte and adipocyte lineages; and they present a surface marker profile corresponding with stem cells derived from AT; CD73+CD90+CD105+CD14-CD19-CD45-HLA-DR. Interestingly, and in opposition to SAT-ASCs, TAT-ASCs have CD14+CD34+CD133+CD45- cells. Moreover, TAT-ASCs from elderly subjects showed higher adipogenic and osteogenic capacities compared to middle aged subjects, indicating that, rather than impairing; aging seems to increase adipogenic and osteogenic capacities of TAT-ASCs. Conclusions This study describes the human TAT as a source of mesenchymal stem cells, which may have an enormous potential for regenerative medicine. PMID:26657132

  13. Heterologous expression of C. elegans fat-1 decreases the n-6/n-3 fatty acid ratio and inhibits adipogenesis in 3T3-L1 cells

    SciTech Connect

    An, Lei; Pang, Yun-Wei; Gao, Hong-Mei; Tao, Li; Miao, Kai; Wu, Zhong-Hong; and others

    2012-11-23

    Highlights: Black-Right-Pointing-Pointer Expression of C. elegans fat-1 reduces the n-6/n-3 PUFA ratio in 3T3-L1 cells. Black-Right-Pointing-Pointer fat-1 inhibits the proliferation and differentiation of 3T3-L1 preadipocytes. Black-Right-Pointing-Pointer fat-1 reduces lipid deposition in 3T3-L1 adipocytes. Black-Right-Pointing-Pointer The lower n-6/n-3 ratio induces apoptosis in 3T3-L1 adipocytes. -- Abstract: In general, a diet enriched in polyunsaturated fatty acids (PUFAs) inhibits the development of obesity and decreases adipose tissue. The specific impacts of n-3 and n-6 PUFAs on adipogenesis, however, have not been definitively determined. Traditional in vivo and in vitro supplementation studies have yielded inconsistent or even contradictory results, which likely reflect insufficiently controlled experimental systems. Caenorhabditiselegans fat-1 gene encodes an n-3 fatty acid desaturase, and its heterologous expression represents an effective method both for altering the n-6/n-3 PUFA ratio and for evaluating the biological effects of n-3 and n-6 PUFAs. We sought to determine whether a reduced n-6/n-3 ratio could influence adipogenesis in 3T3-L1 cells. Lentivirus-mediated introduction of the fat-1 gene into 3T3-L1 preadipocytes significantly reduced the n-6/n-3 ratio and inhibited preadipocyte proliferation and differentiation. In mature adipocytes, fat-1 expression reduced lipid deposition, as measured by Oil Red O staining, and induced apoptosis. Our results indicate that a reduced n-6/n-3 ratio inhibits adipogenesis through several mechanisms and that n-3 PUFAs more effectively inhibit adipogenesis (but not lipogenesis) than do n-6 PUFAs.

  14. Intermitochondrial bridge junctions in fat body cells of the pre-hatch larvae of the forest tent caterpillar Malacosoma disstria HBN.

    PubMed

    Harris, J D

    1979-06-01

    An electron microscopic feature of fat body cells of diapausing Malacosoma disstria pre-hatch caterpillars, experimentally held at certain controlled time-and-temperature conditions, is an elaborate bridge junction, between mitochondria, strikingly similar in appearance to the septate junction which has frequently been described as occurring between cells of many invertebrate species. It is suggested that the intermitochondrial unctions may well represent elaborate forms of interaction between organelles in order to enhance metabolic efficiency in times of stress.

  15. Two paths to fat.

    PubMed

    Rosen, Evan D

    2015-04-01

    Excess caloric intake leads to both the growth of existing fat cells and the generation of new adipocytes. New findings show that PI3K-Akt2 signalling is involved in the differentiation of adult adipose precursor cells—a pathway not required for adipogenesis in the embryo.

  16. Antioxidative Effects of Germinated Brown Rice-Derived Extracts on H2O2-Induced Oxidative Stress in HepG2 Cells

    PubMed Central

    Md Zamri, Nur Diyana; Imam, Mustapha Umar; Abd Ghafar, Siti Aisyah; Ismail, Maznah

    2014-01-01

    The antioxidant properties of germinated brown rice (GBR) are likely mediated by multiple bioactives. To test this hypothesis, HepG2 cells pretreated with GBR extracts, rich in acylated steryl glycoside (ASG), gamma amino butyric acid GABA), phenolics or oryzanol, were incubated with hydrogen peroxide (H2O2) and their hydroxyl radical (OH•) scavenging capacities and thiobarbituric acid-reactive substances (TBARS) generation were evaluated. Results showed that GBR-extracts increased OH• scavenging activities in both cell-free medium and posttreatment culture media, suggesting that the extracts were both direct- and indirect-acting against OH•. The levels of TBARS in the culture medium after treatment were also reduced by all the extracts. In addition, H2O2 produced transcriptional changes in p53, JNK, p38 MAPK, AKT, BAX, and CDK4 that were inclined towards apoptosis, while GBR-extracts showed some transcriptional changes (upregulation of BAX and p53) that suggested an inclination for apoptosis although other changes (upregulation of antioxidant genes, AKT, JNK, and p38 MAPK) suggested that GBR-extracts favored survival of the HepG2 cells. Our findings show that GBR bioactive-rich extracts reduce oxidative stress through improvement in antioxidant capacity, partly mediated through transcriptional regulation of antioxidant and prosurvival genes. PMID:25431609

  17. The effect of immunoglobulins and somatic cells on the gravity separation of fat, bacteria, and spores in pasteurized whole milk.

    PubMed

    Geer, S R; Barbano, D M

    2014-01-01

    Our objective was to determine the role that immunoglobulins and somatic cells (SC) play in the gravity separation of milk. The experiment comprised 9 treatments: (1) low-temperature pasteurized (LTP; 72°C for 17.31s) whole milk; (2) LTP (72°C for 17.31s) whole milk with added bacteria and spores; (3) recombined LTP (72°C for 17.31s) whole milk with added bacteria and spores; (4) high-temperature pasteurized (HTP; 76°C for 7min) whole milk with added bacteria and spores; (5) HTP (76°C for 7min) whole milk with added bacteria and spores and added colostrum; (6) HTP (76°C for 7min) centrifugally separated, gravity-separated (CS GS) skim milk with HTP (76°C for 7min) low-SC cream with added bacteria and spores; (7) HTP (76°C for 7min) CS GS skim milk with HTP (76°C for 7min) high-SC cream with added bacteria and spores; (8) HTP (76°C for 7min) CS GS skim milk with HTP (76°C for 7min) low-SC cream with added bacteria and spores and added colostrum; and (9) HTP (76°C for 7min) CS GS skim milk with HTP (76°C for 7min) high-SC cream with added bacteria and spores and added colostrum. The milks in the 9 treatments were gravity separated at 4°C for 23h in glass columns. Five fractions were collected by weight from each of the column treatments, starting from the bottom of the glass column: 0 to 5%, 5 to 90%, 90 to 96%, 96 to 98%, and 98 to 100%. The SC, fat, bacteria, and spores were measured in each of the fractions. The experiment was replicated 3 times in different weeks using a different batch of milk and different colostrum. Portions of the same batch of the frozen bacteria and spore solutions were used for all 3 replicates. The presence of both SC and immunoglobulins were necessary for normal gravity separation (i.e., rising to the top) of fat, bacteria, and spores in whole milk. The presence of immunoglobulins alone without SC was not sufficient to cause bacteria, fat, and spores to rise to the top. The interaction between SC and immunoglobulins was

  18. Aging alters bone-fat reciprocity by shifting in vivo mesenchymal precursor cell fate towards an adipogenic lineage.

    PubMed

    Singh, Lakshman; Brennan, Tracy A; Russell, Elizabeth; Kim, Jung-Hoon; Chen, Qijun; Brad Johnson, F; Pignolo, Robert J

    2016-04-01

    Bone marrow derived mesenchymal progenitor cells (MPCs) play an important role in bone homeostasis. Age-related changes occur in bone resulting in a decrease in bone density and a relative increase in adipocity. Although in vitro studies suggest the existence of an age-related lineage switch between osteogenic and adipogenic fates, stem cell and microenvironmental contributions to this process have not been elucidated in vivo. In order to study the effects of MPC and microenvironmental aging on functional engraftment and lineage switching, transplantation studies were performed under non-myeloablative conditions in old recipients, with donor MPCs derived from young and old green fluorescent protein (GFP) transgenic mice. Robust engraftment by young MPCs or their progeny was observed in the marrow, bone-lining region and in the matrix of young recipients; however, significantly lower engraftment was seen at the same sites in old recipients transplanted with old MPCs. Differentiation of transplanted MPCs strongly favored adipogenesis over osteogenesis in old recipients irrespective of MPC donor age, suggesting that microenvironmental alterations that occur with in vivo aging are predominately responsible for MPC lineage switching. These data indicate that aging alters bone-fat reciprocity and differentiation of mesenchymal progenitors towards an adipogenic fate.

  19. Adipose-derived mesenchymal stem cells promote the survival of fat grafts via crosstalk between the Nrf2 and TLR4 pathways

    PubMed Central

    Chen, Xiaosong; Yan, Liu; Guo, Zhihui; Chen, Zhaohong; Chen, Ying; Li, Ming; Huang, Chushan; Zhang, Xiaoping; Chen, Liangwan

    2016-01-01

    Autologous fat grafting is an effective reconstructive surgery technique; however, its success is limited by inconsistent graft retention and an environment characterized by high oxidative stress and inflammation. Adipose-derived stem cells (ADSCs) increase the survival of fat grafts, although the underlying mechanisms remain unclear. Here, TLR4−/− and Nrf2−/− mice were used to explore the effects of oxidative stress and inflammation on the viability and function of ADSCs in vitro and in vivo. Enrichment of fat grafts with ADSCs inhibited inflammatory cytokine production, enhanced growth factor levels, increased fat graft survival, downregulated NADPH oxidase (NOX)1 and 4 expression, increased vascularization and reduced ROS production in a manner dependent on toll-like receptor (TLR)-4 and nuclear factor erythroid 2-related factor 2 (Nrf2) expression. Immunohistochemical analysis showed that exposure to hypoxia enhanced ADSC growth and promoted the differentiation of ADSCs into vascular endothelial cells. Hypoxia-induced inflammatory cytokine, growth factor and NOX1/4 upregulation, as well as increased ROS production and apoptosis in ADSCs were dependent on TLR4 and Nrf2, which also modulated the effect of ADSCs on promoting endothelial progenitor cell migration and angiogenesis. Western blot analyses showed that the effects of hypoxia on ADSCs were regulated by crosstalk between Nrf2 antioxidant responses and NF-κB- and TLR4-mediated inflammatory responses. Taken together, our results indicate that ADSCs can increase the survival of fat transplants through the modulation of inflammatory and oxidative responses via Nrf2 and TLR4, suggesting potential strategies to improve the use of ADSCs for cell therapy. PMID:27607584

  20. Stem cell activation in adults can reverse detrimental changes in body composition to reduce fat and increase lean mass in both sexes.

    PubMed

    Wiren, Kristine M; Hashimoto, Joel G; Zhang, Xiao-Wei

    2011-12-01

    Detrimental changes in body composition are often associated with declining levels of testosterone. Here, we evaluated the notion that multipotent mesenchymal stem cells, that give rise to both fat and muscle tissue, can play a significant role to alter existing body composition in the adult. Transgenic mice with targeted androgen receptor (AR) overexpression in stem cells were employed. Wild-type littermate and AR-transgenic male and female mice were gonadectomized and left untreated for 2 months. After the hypogonadal period, mice were then treated with 5α-dihydrotestosterone (DHT) for 6 weeks. After orchidectomy (ORX), wild-type males have reduced lean mass and increased fat mass compared to shams. DHT treatment was beneficial to partially restore body composition. In wild-type females, ovariectomy (OVX) produced a similar change but there was no improvement with DHT. In targeted AR transgenic mice, DHT treatment increased lean and reduced fat mass to sham levels. In contrast to wild-type females, DHT treatment in female transgenic mice significantly ameliorated the increased fat and decreased lean mass changes that result after OVX. Our results show that DHT administration reduces fat mass and increases lean mass in wild-type males but not females, indicating that wild-type females are not as sensitive to androgen treatment. Because both male and female transgenic mice are more responsive than wild-type, results suggest that body composition remains linked to stem cell fate in the adult and that targeted androgen signaling in stem cells can play a significant role to reverse detrimental changes in body composition in both sexes.

  1. Caloric stress alters fat characteristics and Hsp70 expression in milk somatic cells of lactating beef cows.

    PubMed

    Eitam, Harel; Brosh, Arieh; Orlov, Alla; Izhaki, Ido; Shabtay, Ariel

    2009-03-01

    Selection for higher production rate in cattle inhabiting challenging habitats may be considered disadvantageous because of possible deleterious effects on immunity and reproduction and, consequently, on calf crop percentage. In Israel, free-grazing high productive beef cows experience reduction in nutritional quality of forage during up to 8 months of the year. As milk production by dams dictates calf performance, dam's nutritional needs and rebreeding rates, the aim of the present study was to test how lactating beef cows deal with combined caloric and protein stress both at the productive and self protective levels. For this purpose, we studied the effect of long-term caloric stress on milk characteristics and gene expression of stress and milk components producing proteins. Lactating dams responded to caloric stress by decreased body weight, milk, and milk protein production. To compensate for total energy loses in milk, they produced milk of higher fat concentration and shifted the proportions of its fatty acids towards long and unsaturated ones. This was reflected by increased mRNA transcription of the fatty acid binding protein. Prolonged low-energy diet promoted cell-specific heat shock protein (Hsp) response; whereas significant increase of Hsp90 but unchanged levels of Hsp70 proteins were observed in white blood cells, the expression of Hsp70 in milk somatic cells was markedly attenuated, in parallel with a marked increase of alpha(s1)-casein expression. At the mammary gland level, these results may indicate a decrease in turnover of proteins and a shift to an exclusive expression of milk components producing factors. Similar responses to caloric stress were revealed also in ketotic dairy cows. Ketosis promoted a shift towards long and unsaturated fatty acids and an increased expression of alpha(s1)-casein in milk somatic cells. These findings may reflect an evolutionary-preserved mechanism in lactating cows for coping with caloric restriction. Overall

  2. Ascorbate-dependent impact on cell-derived matrix in modulation of stiffness and rejuvenation of infrapatellar fat derived stem cells toward chondrogenesis.

    PubMed

    Pizzute, Tyler; Zhang, Ying; He, Fan; Pei, Ming

    2016-08-10

    Developing an in vitro microenvironment using cell-derived decellularized extracellular matrix (dECM) is a promising approach to efficiently expand adult stem cells for cartilage engineering and regeneration. Ascorbic acid serves as a critical stimulus for cells to synthesize collagens, which constitute the major component of dECM. In this study, we hypothesized that optimization of ascorbate treatment would maximize the rejuvenation effect of dECM on expanded stem cells from human infrapatellar fat pad in both proliferation and chondrogenic differentiation. In the duration regimen study, we found that dECM without L-ascorbic acid phosphate (AA) treatment, exhibiting lower stiffness measured by atomic force microscopy, yielded expanded cells with higher proliferation capacity but lower chondrogenic potential when compared to those with varied durations of AA treatment. dECM with 250 µM of AA treatment for 10 d had better rejuvenation in chondrogenic capacity if the deposited cells were from passage 2 rather than passage 5, despite no significant difference in matrix stiffness. In the dose regimen study, we found that dECMs deposited by varied concentrations of AA yielded expanded cells with higher proliferation capacity despite lower expression levels of stem cell related surface markers. Compared to cells expanded on tissue culture polystyrene, those on dECM exhibited greater chondrogenic potential, particularly for the dECMs with 50 µM and 250 µM of AA treatment. With the supplementation of ethyl-3,4-dihydroxybenzoate (EDHB), an inhibitor targeting procollagen synthesis, the dECM with 50 µM of AA treatment exhibited a dramatic decrease in the rejuvenation effect of expanded cell chondrogenic potential at both mRNA and protein levels despite no significant difference in matrix stiffness. Defined AA treatments during matrix preparation will benefit dECM-mediated stem cell engineering and future treatments for cartilage defects.

  3. Omega-3 fatty acid EPA improves regenerative capacity of mouse skeletal muscle cells exposed to saturated fat and inflammation.

    PubMed

    Saini, Amarjit; Sharples, Adam P; Al-Shanti, Nasser; Stewart, Claire E

    2017-02-01

    Sarcopenic obesity is characterised by high fat mass, low muscle mass and an elevated inflammatory environmental milieu. We therefore investigated the effects of elevated inflammatory cytokine TNF-α (aging/obesity) and saturated fatty acid, palmitate (obesity) on skeletal muscle cells in the presence/absence of EPA, a-3 polyunsaturated fatty acid with proposed anti-inflammatory, anti-obesity activities. In the present study we show that palmitate was lipotoxic, inducing high levels of cell death and blocking myotube formation. Cell death under these conditions was associated with increased caspase activity, suppression of differentiation, reductions in both creatine kinase activity and gene expression of myogenic factors; IGF-II, IGFBP-5, MyoD and myogenin. However, inhibition of caspase activity via administration of Z-VDVAD-FMK (caspase-2), Z-DEVD-FMK (caspase-3) and ZIETD-KMK (caspase 8) was without effect on cell death. By contrast, lipotoxicity associated with elevated palmitate was reduced with the MEK inhibitor PD98059, indicating palmitate induced cell death was MAPK mediated. These lipotoxic conditions were further exacerbated in the presence of inflammation via TNF-α co-administration. Addition of EPA under cytotoxic stress (TNF-α) was shown to partially rescue differentiation with enhanced myotube formation being associated with increased MyoD, myogenin, IGF-II and IGFBP-5 expression. EPA had little impact on the cell death phenotype observed in lipotoxic conditions but did show benefit in restoring differentiation under lipotoxic plus cytotoxic conditions. Under these conditions Id3 (inhibitor of differentiation) gene expression was inversely linked with survival rates, potentially indicating a novel role of EPA and Id3 in the regulation of apoptosis in lipotoxic/cytotoxic conditions. Additionally, signalling studies indicated the combination of lipo- and cyto-toxic effects on the muscle cells acted through ceramide, JNK and MAPK pathways and

  4. Insulin rapidly stimulates phosphorylation of a 46-kDa membrane protein on tyrosine residues as well as phosphorylation of several soluble proteins in intact fat cells.

    PubMed Central

    Häring, H U; White, M F; Machicao, F; Ermel, B; Schleicher, E; Obermaier, B

    1987-01-01

    It is speculated that the transmission of an insulin signal across the plasma membrane of cells occurs through activation of the tyrosine-specific receptor kinase, autophosphorylation of the receptor, and subsequent phosphorylation of unidentified substrates in the cell. In an attempt to identify possible substrates, we labeled intact rat fat cells with [32P]orthophosphate and used an antiphosphotyrosine antibody to identify proteins that become phosphorylated on tyrosine residues in an insulin-stimulated way. In the membrane fraction of the fat cells, we found, in addition to the 95-kDa beta-subunit of the receptor, a 46-kDa phosphoprotein that is phosphorylated exclusively on tyrosine residues. This protein is not immunoprecipitated by antibodies against different regions of the insulin receptor and its HPLC tryptic peptide map is different from the tryptic peptide map of the insulin receptor, suggesting that it is not derived from the receptor beta-subunit. Insulin stimulates the tyrosine phosphorylation of the 46-kDa protein within 150 sec in the intact cell 3- to 4-fold in a dose-dependent way at insulin concentrations between 0.5 nM and 100 nM. The insulin effect starts after 30 sec, is maximal at 150 sec, and declines to almost basal values by 5 min. Furthermore, the antiphosphotyrosine antibody precipitated at least five proteins in the soluble fraction of the fat cell. Insulin (0.5 nM, 100 nM) stimulated within 2 min the 32P incorporation into a 116-kDa band, a 62-kDa band, and three bands between 45 kDa and 50 kDa 2- to 10-fold. We suggest that the 46-kDa membrane protein and possibly also the soluble proteins are endogenous substrates of the receptor tyrosine kinase in fat cells and that their phosphorylation is an early step in insulin signal transmission. Images PMID:3540953

  5. Miglitol prevents diet-induced obesity by stimulating brown adipose tissue and energy expenditure independent of preventing the digestion of carbohydrates.

    PubMed

    Sasaki, Tsutomu; Shimpuku, Mayumi; Kitazumi, Tomoya; Hiraga, Haruna; Nakagawa, Yuko; Shibata, Hiroshi; Okamatsu-Ogura, Yuko; Kikuchi, Osamu; Kim, Hye-jin; Fujita, Yuki; Maruyama, Jun; Susanti, Vina Yanti; Yokota-Hashimoto, Hiromi; Kobayashi, Masaki; Saito, Masayuki; Kitamura, Tadahiro

    2013-01-01

    Miglitol is an alpha-glucosidase inhibitor that improves post-prandial hyperglycemia, and it is the only drug in its class that enters the bloodstream. Anecdotally, miglitol lowers patient body weight more effectively than other alpha-glucosidase inhibitors, but the precise mechanism has not been addressed. Therefore, we analyzed the anti-obesity effects of miglitol in mice and in the HB2 brown adipocyte cell line. Miglitol prevented diet-induced obesity by stimulating energy expenditure without affecting food intake in mice. Long-term miglitol treatment dose-dependently prevented diet-induced obesity and induced mitochondrial gene expression in brown adipose tissue. The anti-obesity effect was independent of preventing carbohydrate digestion in the gastrointestinal tract. Miglitol effectively stimulated energy expenditure in mice fed a high-fat high-monocarbohydrate diet, and intraperitoneal injection of miglitol was sufficient to stimulate energy expenditure in mice. Acarbose, which is a non-absorbable alpha glucosidase inhibitor, also prevented diet-induced obesity, but through a different mechanism: it did not stimulate energy expenditure, but caused indigestion, leading to less energy absorption. Miglitol promoted adrenergic signaling in brown adipocytes in vitro. These data indicate that circulating miglitol stimulates brown adipose tissue and increases energy expenditure, thereby preventing diet-induced obesity. Further optimizing miglitol's effect on brown adipose tissue could lead to a novel anti-obesity drug.

  6. Reducing Smad3/ATF4 was essential for Sirt1 inhibiting ER stress-induced apoptosis in mice brown adipose tissue.

    PubMed

    Liu, Zhenjiang; Gu, Huihui; Gan, Lu; Xu, Yatao; Feng, Fei; Saeed, Muhammad; Sun, Chao

    2017-02-07

    Sirtuin 1 (Sirt1) promotes adaptive thermogenesis by controlling the acetylation status of enzymes and transcriptional factors in interscapular brown adipose tissue (iBAT). However, the effects of Sirt1 on endoplasmic reticulum (ER) stress and apoptosis of iBAT remain elusive. In this study, the mRNA levels of Sirt1 and thermogenesis genes were reduced but the genes related with ER stress were elevated in iBAT of high-fat diet (HFD)-induced obese mice. Moreover, ER stress further inhibited mRNA level of Sirt1 and triggered brown adipocyte apoptosis in vitro and in vivo. Further analysis revealed that Sirt1 overexpression alleviated ER stress-induced brown adipocyte apoptosis by inhibiting Smad3 and ATF4. In addition, Smad3 bound to ATF4 promoter region and positively transcriptional regulation of ATF4. Our data also confirmed that Sirt1 reduced early apoptotic cells and blocked the mitochondrial apoptosis pathway by directly interacting with ATF4. Furthermore, Sirt1 attenuated tunicamycin-induced cold intolerance and elevating thermogenesis by inhibiting ER stress and apoptosis in iBAT. In summary, our data collectively revealed Sirt1 reduced ER stress and apoptosis of brown adipocyte in vivo and in vitro by inhibiting Smad3/ATF4 signal. These data reveal a novel mechanism that links Sirt1 to brown adipocyte apoptosis.

  7. Spectroscopy of Brown Dwarfs

    NASA Astrophysics Data System (ADS)

    Rebolo, R.

    Recent searches for brown dwarfs have succeeded in finding these elusive objects. Massive brown dwarfs (40-70 Jupiter masses) have been found in the Pleiades, orbiting around a nearby star and, very recently, in the field. A review is given of their observed photometric and spectroscopic properties in the optical and near-infrared. The diagnosis of substellar nature based on lithium lines and methane bands is discussed in detail. While lithium has proved useful to test brown dwarfs with effective temperatures hotter than ~1600 K, methane is a substellar indicator at lower temperatures.

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

    SciTech Connect

    Brückner, Sandra; Tautenhahn, Hans-Michael; Winkler, Sandra; Stock, Peggy; Dollinger, Matthias; Christ, Bruno

    2014-02-15

    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 in 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

  9. Suppression of adipogenic differentiation by muscle cell-induced decrease in genes related to lipogenesis in muscle and fat co-culture system.

    PubMed

    Park, Sungkwon; Baek, Kyunghoon; Choi, Changbon

    2013-09-01

    Intercellular signalling communication between adipose and muscle tissue has been investigated. To test the effect of muscle cells on adipogenic gene expression, we utilised an in vitro co-culture system, in which fat (3T3-L1) and muscle (L-6) cells were physically separated but chemically exposed each other via insert with 0.4 µm porous membrane. When 3T3-L1 and L-6 cells reached at 80 and 40% confluence, respectively in separate wells, L-6 cells grown in insert were transferred onto 6-well plates where 3T3-L1 cells were being grown. When both cells were fully differentiated in co-culture plates, morphology of 3T3-L1 was examined by staining with Oil-red-O. Activity of glycerol-3-phosphate dehydrogenase (GPDH) and adipogenic gene expression including lipoprotein lipase (LPL), adipsin, GPDH, peroxisome proliferator-activated receptor-γ (PPARγ) and CCAAT/enhancer binding protein (C/EBPα) were analysed. The presence of muscle cells during preadipocyte differentiation inhibited (P < 0.05) lipogenesis by suppressing lipogenic gene expression including LPL, adipsin and GPDH. Furthermore, GPDH activity was also decreased (P < 0.05) in 3T3-L1 cells by the presence of L-6 cells. These results suggest that presence of muscle cells suppresses adipogenic differentiation by inhibiting the adipogenic gene expression and GPDH activity in the muscle and fat cell co-culture system.

  10. The regulation of glucose on milk fat synthesis is mediated by the ubiquitin-proteasome system in bovine mammary epithelial cells.

    PubMed

    Liu, Lily; Jiang, Li; Ding, Xiang-dong; Liu, Jian-feng; Zhang, Qin

    2015-09-11

    Glucose as one of the nutrition factors plays a vital role in the regulation of milk fat synthesis. Ubiqu