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Sample records for brown fat thyroxine

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

    International Nuclear Information System (INIS)

    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 (T4) to triiodothyronine (T3) in BAT. A total of 34 lean and obese rats, ∼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 +/- 10C) for 7 days. Activity of T4 5'-deiodinase was determined as the rate of T3 production from added T4 under controlled in vitro conditions. Serum T4 and T3 were determined by radioimmunoassay. The rate of T4-to-T3 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 T3 production whereas only a small increase was observed in the cold-exposed obese rats. Serum T3 levels tended to be reduced in the Zucker obese rats. The data indicate a reduced capacity for T3 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

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

    Energy Technology Data Exchange (ETDEWEB)

    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.

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

    International Nuclear Information System (INIS)

    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 T4 to T3 in BAT, through activity of T4 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 220C+/-2. Group 3 was fed rat chow and maintained at 80C+/-1 for 7 days. Activity of T45'deiodinase was determined in vitro. T3 was measured by a radioimmunoassay. The rate of T4 to T3 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 T3/scapular BAT depot, per hour). However, lean rats exposed to the cold displayed about a 5 fold increase in T45' deiodinase activity (p3 may account for the reduced tolerance of obese animals to cold, but it does not account for their reduced diet induced BAT thermogenesis

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

    Energy Technology Data Exchange (ETDEWEB)

    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.

  5. Brown Fat Cell Isolation

    OpenAIRE

    sprotocols

    2014-01-01

    Author: C.R. Kahn ### 1.) ISOLATION AND PRIMARY CULTURE OF BROWN FAT PREADIPOCYTES ### Rationale: To prepare primary brown preadipocytes for immortalization: useful for metabolic studies from knockout mice. This consists of the following five protocols. References: Fasshauer, M., J. Klein, K M. Kriauciunas, K. Ueki, M.Benito, and C.R. Kahn. 2001. Essential role of insulin substrate 1 in differentiation of brown adipocytes. *Mol Cell Biol* 21: 319-329. Fasshauer, M....

  6. Novel nuances of human brown fat

    DEFF Research Database (Denmark)

    Scheele, Camilla; Larsen, Therese Juhlin; Nielsen, Søren

    2014-01-01

    There is a current debate in the literature on whether human fat derived from the supraclavicular region should be classified as brown, or as the white fat-derived less potent, brite/beige. This commentary addresses whether the existing classification defined in mice is sufficient to describe the...... types of thermogenic adipocytes in humans. We recently published a contradictory mRNA expression signature of human supraclavicular fat defined by an upregulation of the brite marker TBX1 along with the classical brown markers ZIC1 and LHX8, as well as genes indicating brown fat activity including UCP1......, there was no difference in UCP1, PGC-1α, PRDM16, suggesting both depots had equal brown fat potency. Taken together, supraclavicular brown fat derived from adult humans seems to represent a type of brown fat with distinct features from both subcutaneous white/brite and interscapular brown fat. Therefore...

  7. Dietary Fat Overload Reprograms Brown Fat Mitochondria

    Directory of Open Access Journals (Sweden)

    DANIELE eLETTIERI BARBATO

    2015-09-01

    Full Text Available Chronic nutrient overload accelerates the onset of several aging-related diseases reducing life expectancy. Although the mechanisms by which overnutrition affects metabolic processes in many tissues are known, its role on BAT physiology is still unclear. Herein, we investigated the mitochondrial responses in BAT of female mice exposed to high fat diet (HFD at different steps of life. Although adult mice showed an unchanged mitochondrial amount, both respiration and OxPHOS subunits were strongly affected. Differently, offspring pups exposed to HFD during pregnancy and lactation displayed reduced mitochondrial mass but high oxidative efficiency that, however, resulted in increased bioenergetics state of BAT rather than augmented uncoupling respiration. Interestingly, the metabolic responses triggered by HFD were accompanied by changes in mitochondrial dynamics characterized by decreased content of the fragmentation marker Drp1 both in mothers and offspring pups. HFD-induced inactivation of the FoxO1 transcription factor seemed to be the up-stream modulator of Drp1 levels in brown fat cells. Furthermore, HFD offspring pups weaned with normal diet only partially reverted the mitochondrial dysfunctions caused by HFD. Finally these mice failed in activating the thermogenic program upon cold exposure. Collectively our findings suggest that maternal dietary fat overload irreversibly commits BAT unresponsiveness to physiological stimuli such as cool temperature and this dysfunction in the early stage of life might negatively modulates health and lifespan.

  8. Dietary fat overload reprograms brown fat mitochondria

    OpenAIRE

    Lettieri Barbato, Daniele; Tatulli, Giuseppe; Vegliante, Rolando; Cannata, Stefano M.; Bernardini, Sergio; Ciriolo, Maria R.; Aquilano, Katia

    2015-01-01

    Chronic nutrient overload accelerates the onset of several aging-related diseases reducing life expectancy. Although the mechanisms by which overnutrition affects metabolic processes in many tissues are known, its role on BAT physiology is still unclear. Herein, we investigated the mitochondrial responses in BAT of female mice exposed to high fat diet (HFD) at different steps of life. Although adult mice showed an unchanged mitochondrial amount, both respiration and OxPHOS subunits were stron...

  9. Transcriptional Regulatory Circuits Controlling Brown Fat Development and Activation

    OpenAIRE

    Seale, Patrick

    2015-01-01

    Brown and beige adipose tissue is specialized for heat production and can be activated to reduce obesity and metabolic dysfunction in animals. Recent studies also have indicated that human brown fat activity levels correlate with leanness. This has revitalized interest in brown fat biology and has driven the discovery of many new regulators of brown fat development and function. This review summarizes recent advances in our understanding of the transcriptional mechanisms that control brown an...

  10. PRDM16 Controls a Brown Fat/Skeletal Muscle Switch

    OpenAIRE

    Seale, Patrick; Bjork, Bryan; Yang, Wenli; Kajimura, Shingo; Kuang, Shihuan; Scime, Anthony; Devarakonda, Srikripa; Chin, Sherry; Conroe, Heather M.; Erdjument-Bromage, Hediye; Tempst, Paul; Rudnicki, Michael A.; Beier, David R; Spiegelman, Bruce M.

    2008-01-01

    Brown fat can increase energy expenditure and protect against obesity through a specialized program of uncoupled respiration. We show here by in vivo fate mapping that brown but not white fat cells arise from precursors that express myf5, a gene previously thought to be expressed only in the myogenic lineage. Notably, the transcriptional regulator, PRDM16 controls a bidirectional cell fate switch between skeletal myoblasts and brown fat cells. Loss of PRDM16 from brown fat precursors causes a...

  11. Brown Fat Paucity Due to Impaired BMP Signaling Induces Compensatory Browning of White Fat

    OpenAIRE

    Schulz, Tim J.; Huang, Ping; Huang, Tian Lian; Xue, Ruidan; McDougall, Lindsay E.; Townsend, Kristy L.; Cypess, Aaron M.; Mishina, Yuji; Gussoni, Emanuela; Tseng, Yu-Hua

    2013-01-01

    Summary Maintenance of body temperature is essential for survival of homeotherms. Brown adipose tissue (BAT) is a specialized fat tissue that is dedicated to thermoregulation 1 . Due to its remarkable capacity to dissipate stored energy and its demonstrated presence in adult humans 2-5 , BAT holds great promise for the treatment of obesity and metabolic syndrome 1 . Rodent data suggest the existence of two types of brown fat cells: the constitutive BAT (cBAT), which is of embryonic origin and...

  12. Brown Fat Paucity Due to Impaired BMP Signaling Induces Compensatory Browning of White Fat

    OpenAIRE

    Schulz, Tim J.; Huang, Ping; Huang, Tian Lian; Xue, Ruidan; McDougall, Lindsay E.; Townsend, Kristy L.; Cypess, Aaron M.; Mishina, Yuji; Gussoni, Emanuela; Tseng, Yu-Hua

    2013-01-01

    Summary Maintenance of body temperature is essential for survival of homeotherms. Brown adipose tissue (BAT) is a specialized fat tissue that is dedicated to thermoregulation1. Due to its remarkable capacity to dissipate stored energy and its demonstrated presence in adult humans2-5, BAT holds great promise for the treatment of obesity and metabolic syndrome1. Rodent data suggest the existence of two types of brown fat cells: the constitutive BAT (cBAT), which is of embryonic origin and anato...

  13. Transcriptional Control of Brown Fat Determination by PRDM16

    OpenAIRE

    Seale, Patrick; Kajimura, Shingo; Yang, Wenli; Chin, Sherry; Rohas, Lindsay; Uldry, Marc; Tavernier, Geneviève; Langin, Dominique; Spiegelman, Bruce M.

    2007-01-01

    Brown fat cells are specialized to dissipate energy and can counteract obesity; however, the transcriptional basis of their determination is largely unknown. We show here that the zinc-finger protein PRDM16 is highly enriched in brown fat cells compared to white fat cells. When expressed in white fat cell progenitors, PRDM16 activates a robust brown fat phenotype including induction of PGC-1α, UCP1 and type 2 deiodinase expression, and a remarkable increase in uncoupled respiration. Transgeni...

  14. Brown fat and vascular heat dissipation

    OpenAIRE

    Warner, Amy; Mittag, Jens

    2014-01-01

    Current efforts to treat obesity and associated disorders focus on the stimulation of energy expenditure by increasing thermogenesis, for instance through activating brown adipose tissue or more recently “beige” or “brite” fat, a relatively novel type of adipose tissue with putative thermogenic potential. In this commentary, we aim to provide an alternative perspective on the current trend of analyzing and manipulating thermogenesis, brought about by our recent publication, in which we invest...

  15. The brown fat secretome: metabolic functions beyond thermogenesis

    OpenAIRE

    Wang, Guo-Xiao; Zhao, Xu-Yun; Lin, Jiandie D.

    2015-01-01

    Brown fat is highly active in fuel oxidation and dissipates chemical energy through uncoupling protein 1 (UCP1)-mediated heat production. Activation of brown fat leads to increased energy expenditure, reduced adiposity, and lower plasma glucose and lipid levels, thus contributing to better homeostasis. Uncoupled respiration and thermogenesis have been considered to be responsible for the metabolic benefits of brown adipose tissue. Recent studies have demonstrated that brown adipocytes also se...

  16. Morphogenetics in brown, beige and white fat development.

    Science.gov (United States)

    Lin, Jean Z; Farmer, Stephen R

    2016-01-01

    Brown and beige (or brite) fat cells are capable of evoking non-shivering thermogenesis in response to cold and β-adrenergic stimulation. By metabolizing lipids and carbohydrate via uncoupled respiration these cells directly convert energy to heat. The discovery of brown and brown-like adipocytes in adult humans has reinvigorated interest in stimulating brown and beige fat development to combat the obesity epidemic. This review focuses on the role that cytoskeleton dynamics play in the regulation of adipocyte biology, specifically beige and brown fat development and how newly discovered adipogenic morphogens affect these processes. PMID:27386157

  17. FAT TISSUE DISTRIBUTION BETWEEN SUBCUTANEOUS AND INTERMUSCULAR FAT TISSUE IN SIMMENTAL AND BROWN BULLS

    Directory of Open Access Journals (Sweden)

    S. Žgur

    2007-06-01

    Full Text Available Simmental and Brown bulls from progeny testing station were used to evaluate the effect of breed on fat tissue partition between subcutaneous and intermuscular fat. Bulls (37 Brown and 34 Simmental breed were slaughtered at the same degree of fatness. After slaughter carcasses were first cut into different carcass cuts and further on into lean meat, fat, bones and tendons. Fat was divided up into subcutaneous and intermuscular. Simmental bulls were heavier (average cold carcass side weight from Simmental bulls was 167 kg vs 147 kg from Brown bulls at the same percentage of total carcass fat (10.5 %. Breed has no effect on percentage of subcutaneous and intermuscular fat tissue nor on percentage of subcutaneous fat from total carcass fat. Simmental bulls had higher (p<0.05 subcutaneous fat percentage (subcutaneous fat in the cut / total fat in the cut in brisket and flank and lower (p<0.05 in shoulder than Brown bulls.

  18. Brown Fat and Browning for the Treatment of Obesity and Related Metabolic Disorders

    Directory of Open Access Journals (Sweden)

    So Hun Kim

    2016-02-01

    Full Text Available Brown fat is a specialized fat depot that can increase energy expenditure and produce heat. After the recent discovery of the presence of active brown fat in human adults and novel transcription factors controlling brown adipocyte differentiation, the field of the study of brown fat has gained great interest and is rapidly growing. Brown fat expansion and/or activation results in increased energy expenditure and a negative energy balance in mice and limits weight gain. Brown fat is also able to utilize blood glucose and lipid and results in improved glucose metabolism and blood lipid independent of weight loss. Prolonged cold exposure and beta adrenergic agonists can induce browning of white adipose tissue. The inducible brown adipocyte, beige adipocyte evolving by thermogenic activation of white adipose tissue have different origin and molecular signature from classical brown adipocytes but share the characteristics of high mitochondria content, UCP1 expression and thermogenic capacity when activated. Increasing browning may also be an efficient way to increase whole brown fat activity. Recent human studies have shown possibilities that findings in mice can be reproduced in human, making brown fat a good candidate organ to treat obesity and its related disorders.

  19. FAT TISSUE DISTRIBUTION BETWEEN SUBCUTANEOUS AND INTERMUSCULAR FAT TISSUE IN SIMMENTAL AND BROWN BULLS

    OpenAIRE

    Silvester Žgur; Marko Čepon

    2007-01-01

    Simmental and Brown bulls from progeny testing station were used to evaluate the effect of breed on fat tissue partition between subcutaneous and intermuscular fat. Bulls (37 Brown and 34 Simmental breed) were slaughtered at the same degree of fatness. After slaughter carcasses were first cut into different carcass cuts and further on into lean meat, fat, bones and tendons. Fat was divided up into subcutaneous and intermuscular. Simmental bulls were heavier (average cold carcass side weight ...

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

    OpenAIRE

    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 br...

  1. Ouabain-sensitive component of brown fat thermogenesis.

    Science.gov (United States)

    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.

  2. Human brown fat and obesity: methodological aspects

    OpenAIRE

    WouterDavidVan Marken Lichtenbelt

    2011-01-01

    Much is known about brown adipose tissue 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 atten...

  3. Human Brown Fat and Obesity: Methodological Aspects

    OpenAIRE

    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...

  4. Human brown fat and obesity: methodological aspects

    Directory of Open Access Journals (Sweden)

    WouterDavidVan Marken Lichtenbelt

    2011-10-01

    Full Text Available Much is known about brown adipose tissue 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.

  5. Can Brown Fat Win the Battle Against White Fat?

    Science.gov (United States)

    Elattar, Sawsan; Satyanarayana, Ande

    2015-10-01

    A rapid growth in the overweight and obese population in the last few decades suggest that the current diet, exercise, awareness or drug strategies are still not effectively restraining the obesity epidemic. Obesity results from increased energy intake, and the body's energy balance shifts towards energy abundance. Therefore, current research is focused on developing new strategies aimed at increasing energy expenditure. As a result, brown adipose tissue (BAT) is receiving tremendous attention since the major function of BAT is to dissipate energy as heat. For example, mouse models that have increased BAT activity or increased numbers of brown-like adipocytes within the white adipose tissue (WAT) are lean and protected from obesity. Alternatively, mouse models that lack BAT activity are more susceptible to age and diet-induced obesity. However, a significant loss of BAT mass during the natural growth process in humans has created enormous challenges in effectively utilizing this tissue to increase energy expenditure. New strategies are primarily focused on expanding the BAT mass and/or activating the existing BAT. In this regard, recent finding that expression of early B cell factor-2 (Ebf2) reprograms the white pre-adipocytes into brown adipocytes is a significant break-through in developing BAT-mediated strategies to treat obesity. Here we review the major biological functions of WAT and BAT, which play critical but opposing roles in the energy spectrum, energy storage versus energy expenditure, and we evaluate whether activation and/or expansion of BAT is practically achievable to treat obesity in humans. PMID:25760392

  6. Severe Brown Fat Lipoatrophy Aggravates Atherosclerotic Process in Male Mice.

    Science.gov (United States)

    Gómez-Hernández, Almudena; Beneit, Nuria; Escribano, Óscar; Díaz-Castroverde, Sabela; García-Gómez, Gema; Fernández, Silvia; Benito, Manuel

    2016-09-01

    Obesity is one of the major risk factors for the development of cardiovascular diseases and is characterized by abnormal accumulation of adipose tissue, including perivascular adipose tissue (PVAT). However, brown adipose tissue (BAT) activation reduces visceral adiposity. To demonstrate that severe brown fat lipoatrophy might accelerate atherosclerotic process, we generated a new mouse model without insulin receptor (IR) in BAT and without apolipoprotein (Apo)E (BAT-specific IR knockout [BATIRKO];ApoE(-/-) mice) and assessed vascular and metabolic alterations associated to obesity. In addition, we analyzed the contribution of the adipose organ to vascular inflammation. Brown fat lipoatrophy induces visceral adiposity, mainly in gonadal depot (gonadal white adipose tissue [gWAT]), severe glucose intolerance, high postprandial glucose levels, and a severe defect in acute insulin secretion. BATIRKO;ApoE(-/-) mice showed greater hypertriglyceridemia than the obtained in ApoE(-/-) and hypercholesterolemia similar to ApoE(-/-) mice. BATIRKO;ApoE(-/-) mice, in addition to primary insulin resistance in BAT, also showed a significant decrease in insulin signaling in liver, gWAT, heart, aorta artery, and thoracic PVAT. More importantly, our results suggest that severe brown fat lipoatrophy aggravates the atherosclerotic process, characterized by a significant increase of lipid depots, atherosclerotic coverage, lesion size and complexity, increased macrophage infiltration, and proinflammatory markers expression. Finally, an increase of TNF-α and leptin as well as a decrease of adiponectin by BAT, gWAT, and thoracic PVAT might also be responsible of vascular damage. Our results suggest that severe brown lipoatrophy aggravates atherosclerotic process. Thus, BAT activation might protect against obesity and its associated metabolic alterations. PMID:27414981

  7. Role of energy metabolism in the brown fat gene program

    OpenAIRE

    Minwoo eNam; Marcus eCooper

    2015-01-01

    In murine and human brown adipose tissue (BAT), mitochondria are powerful generators of heat that safely metabolize fat, a feature that has great promise in the fight against obesity and diabetes. Recent studies suggest that the action of mitochondria extend beyond their conventional role as generators of heat. There is mounting evidence that impaired mitochondrial respiratory capacity is accompanied by attenuated expression of Ucp1 and other BAT-selective genes, implying that mitochondria ex...

  8. Does Brown Fat Protect Against Diseases of Aging?

    OpenAIRE

    Mark P Mattson

    2009-01-01

    The most commonly studied laboratory rodents possess a specialized form of fat called brown adipose tissue (BAT) that generates heat to help maintain body temperature in cold environments. In humans, BAT is abundant during embryonic and early postnatal development, but is absent or present in relatively small amounts in adults where it is located in paracervical and supraclavicular regions. BAT cells can `burn' fatty acid energy substrates to generate heat because they possess large numbers o...

  9. Browning and graying: novel transcriptional regulators of brown and beige fat tissues and aging

    Directory of Open Access Journals (Sweden)

    Elisabetta eMueller

    2016-03-01

    Full Text Available Obesity represents a major risk factor for the development of a number of metabolic disorders, including cardiovascular disease and type 2 diabetes. Since the discovery that brown and beige fat cells exist in adult humans and contribute to energy expenditure, increasing interest has been devoted to the understanding of the molecular switches turning on calorie utilization. It has been reported that the ability of thermogenic tissues to burn energy declines during aging, possibly contributing to the development of metabolic dysfunction late in life. This review will focus on the recently identified transcriptional modulators of brown and beige cells and will discuss the potential impact of some of these thermogenic factors on age-associated metabolic disorders.

  10. MicroRNA-378 controls classical brown fat expansion to counteract obesity

    OpenAIRE

    Pan, Dongning; Mao, Chunxiao; Quattrochi, Brian; Friedline, Randall H.; Zhu, Lihua J.; Jung, Dae Young; Kim, Jason K.; Lewis, Brian; Wang, Yong-Xu

    2014-01-01

    Both classical brown adipocytes and brown-like beige adipocytes are considered as promising therapeutic targets for obesity; however, their development, relative importance, and functional coordination are not well understood. Here we show that a modest expression of miR-378/378* in adipose tissue specifically increases classical brown fat (BAT) mass, but not white fat (WAT) mass. Remarkably, BAT expansion, rather than miR-378 per se, suppresses formation of beige adipocytes in subcutaneous W...

  11. Characterization of a primary brown adipocyte culture system derived from human fetal interscapular fat

    OpenAIRE

    Seiler, Sarah E.; Xu, Dan; Ho, Jia-Pei; Lo, Kinyui Alice; Buehrer, Benjamin M; Ludlow, Y John W; Kovalik, Jean-Paul; Sun, Lei

    2015-01-01

    Brown fat has gained widespread attention as a potential therapeutic target to treat obesity and associated metabolic disorders. Indeed, the anti-obesity potential of multiple targets to stimulate both brown adipocyte differentiation and recruitment have been verified in rodent models. However, their therapeutic potential in humans is unknown due to the lack of a human primary brown adipocyte cell culture system. Likewise, the lack of a well-characterized human model has limited the discovery...

  12. Dynamic regulation of genes involved in mitochondrial DNA replication and transcription during mouse brown fat cell differentiation and recruitment

    DEFF Research Database (Denmark)

    Murholm, Maria; Dixen, Karen; Qvortrup, Klaus;

    2009-01-01

    ) 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...... 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...

  13. A new era in brown adipose tissue biology: molecular control of brown fat development and energy homeostasis.

    Science.gov (United States)

    Kajimura, Shingo; Saito, Masayuki

    2014-01-01

    Brown adipose tissue (BAT) is specialized to dissipate chemical energy in the form of heat as a defense against cold and excessive feeding. Interest in the field of BAT biology has exploded in the past few years because of the therapeutic potential of BAT to counteract obesity and obesity-related diseases, including insulin resistance. Much progress has been made, particularly in the areas of BAT physiology in adult humans, developmental lineages of brown adipose cell fate, and hormonal control of BAT thermogenesis. As we enter into a new era of brown fat biology, the next challenge will be to develop strategies for activating BAT thermogenesis in adult humans to increase whole-body energy expenditure. This article reviews the recent major advances in this field and discusses emerging questions. PMID:24188710

  14. Duodenal Lipid Sensing Activates Vagal Afferents to Regulate Non-Shivering Brown Fat Thermogenesis in Rats

    OpenAIRE

    Blouet, Clémence; Schwartz, Gary J.

    2012-01-01

    Previous evidence indicates that duodenal lipid sensing engages gut-brain neurocircuits to determine food intake and hepatic glucose production, but a potential role for gut-brain communication in the control of energy expenditure remains to be determined. Here, we tested the hypothesis that duodenal lipid sensing activates a gut–brain–brown adipose tissue neuraxis to regulate thermogenesis. We demonstrate that direct administration of lipids into the duodenum increases brown fat temperature....

  15. Systemic control of brown fat thermogenesis: integration of peripheral and central signals

    OpenAIRE

    Schulz, Tim J.; Tseng, Yu-Hua

    2013-01-01

    Brown adipose tissue (BAT) is of great scientific interest as a potential target to treat obesity. The development of novel strategies to quantify brown fat thermogenesis in adult humans now enables minimally invasive assessment of novel pharmacotherapeutics. Input from the central nervous system (CNS) via sympathetic efferents is widely regarded as the key controller of BAT-mediated thermogenesis in response to changes in body temperature or nutrient availability. More recently, however, it ...

  16. Intravitreally Injected Anti-VEGF Antibody Reduces Brown Fat in Neonatal Mice.

    Directory of Open Access Journals (Sweden)

    Dong Hyun Jo

    Full Text Available Anti-vascular endothelial growth factor (VEGF agents are the mainstay treatment for various angiogenesis-related retinal diseases. Currently, bevacizumab, a recombinant humanized anti-VEGF antibody, is trailed in retinopathy of prematurity, a vasoproliferative retinal disorder in premature infants. However, the risks of systemic complications after intravitreal injection of anti-VEGF antibody in infants are not well understood. In this study, we show that intravitreally injected anti-VEGF antibody is transported into the systemic circulation into the periphery where it reduces brown fat in neonatal C57BL/6 mice. A considerable amount of anti-VEGF antibody was detected in serum after intravitreal injection. Furthermore, in interscapular brown adipose tissue, we found lipid droplet accumulation, decreased VEGF levels, loss of vascular network, and decreased expression of mitochondria-related genes, Ppargc1a and Ucp1, all of which are characteristics of "whitening" of brown fat. With increasing age and body weight, brown fat restored its morphology and vascularity. Our results show that there is a transient, but significant impact of intravitreally administered anti-VEGF antibody on brown adipose tissue in neonatal mice. We suggest that more attention should be focused on the metabolic and developmental significance of brown adipose tissue in bevacizumab treated retinopathy of prematurity infants.

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

    NARCIS (Netherlands)

    Berbeé, J.F.P.; Boon, M.R.; Khedoe, P.P.S.J.; Bartelt, A.; Schlein, C.; Worthmann, A.; Kooijman, S.; Hoeke, G.; Mol, I.M.; John, C.; Jung, C.; Vazirpanah, N.; Brouwers, L.P.J.; Gordts, P.L.S.M.; Esko, J.D.; Hiemstra, P.S.; Havekes, L.M.; Scheja, L.; Heeren, J.; Rensen, P.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 b3-adrenergic rece

  18. Brown Fat and the Myth of Diet-Induced Thermogenesis

    OpenAIRE

    Kozak, Leslie P.

    2010-01-01

    The notion that brown adipose tissue (BAT) in mice or humans maintains energy balance by burning off excess calories seems incompatible with evolutionary biology. Studies in obese rats and mice lacking UCP1 indicate that diet-induced thermogenesis by BAT is unlikely.

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

    DEFF Research Database (Denmark)

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

    2004-01-01

    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....

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

    International Nuclear Information System (INIS)

    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 [3H]lysine (87.3 Ci/mM specific activity), [3H]arginine (16.7 Ci/mM), [3H]glycerol (43 Ci/mM), or [3H]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 K2 emulsion, and the preparations were exposed for 20 days at 40C 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

  1. Assessment of oxidative metabolism in Brown Fat using PET imaging

    OpenAIRE

    Otto eMuzik; Mangner, Thomas J.; Granneman, James G.

    2012-01-01

    Objective: Although it has been believed that brown adipose tissue (BAT) depots disappear shortly after the perinatal period in humans, PET imaging using the glucose analog FDG has shown unequivocally the existence of functional BAT in humans. The objective of this study was to determine, using dynamic oxygen-15 (15O) PET imaging, to what extent BAT thermogenesis is activated in adults during cold stress and to establish the relationship between BAT oxidative metabolism and FDG tracer uptake....

  2. Vascular rarefaction mediates whitening of brown fat in obesity

    OpenAIRE

    Shimizu, Ippei; Aprahamian, Tamar; Kikuchi, Ryosuke; Shimizu, Ayako; Papanicolaou, Kyriakos N.; MacLauchlan, Susan; Maruyama, Sonomi; Walsh, Kenneth

    2014-01-01

    Brown adipose tissue (BAT) is a highly vascularized organ with abundant mitochondria that produce heat through uncoupled respiration. Obesity is associated with a reduction of BAT function; however, it is unknown how obesity promotes dysfunctional BAT. Here, using a murine model of diet-induced obesity, we determined that obesity causes capillary rarefaction and functional hypoxia in BAT, leading to a BAT “whitening” phenotype that is characterized by mitochondrial dysfunction, lipid droplet ...

  3. Assessment of Oxidative Metabolism in Brown Fat Using PET Imaging

    OpenAIRE

    Muzik, Otto; Mangner, Thomas J.; Granneman, James G.

    2012-01-01

    Objective: Although it has been believed that brown adipose tissue (BAT) depots disappear shortly after the perinatal period in humans, positron emission tomography (PET) imaging using the glucose analog 18F-deoxy-d-glucose (FDG) has shown unequivocally the existence of functional BAT in humans, suggesting that most humans have some functional BAT. The objective of this study was to determine, using dynamic oxygen-15 (15O) PET imaging, to what extent BAT thermogenesis is activated in adults d...

  4. Role of Brown Fat in Lipoprotein Metabolism and Atherosclerosis.

    Science.gov (United States)

    Hoeke, Geerte; Kooijman, Sander; Boon, Mariëtte R; Rensen, Patrick C N; Berbée, Jimmy F P

    2016-01-01

    Atherosclerosis, for which hyperlipidemia is a major risk factor, is the leading cause of morbidity and mortality in Western society, and new therapeutic strategies are highly warranted. Brown adipose tissue (BAT) is metabolically active in human adults. Although positron emission tomography-computed tomography using a glucose tracer is the golden standard to visualize and quantify the volume and activity of BAT, it has become clear that activated BAT combusts fatty acids rather than glucose. Here, we review the role of brown and beige adipocytes in lipoprotein metabolism and atherosclerosis, with evidence derived from both animal and human studies. On the basis of mainly data from animal models, we propose a model in which activated brown adipocytes use their intracellular triglyceride stores to generate fatty acids for combustion. BAT rapidly replenishes these stores by internalizing primarily lipoprotein triglyceride-derived fatty acids, generated by lipoprotein lipase-mediated hydrolysis of triglycerides, rather than by holoparticle uptake. As a consequence, BAT activation leads to the generation of lipoprotein remnants that are subsequently cleared via the liver provided that an intact apoE-low-density lipoprotein receptor pathway is present. Through these mechanisms, BAT activation reduces plasma triglyceride and cholesterol levels and attenuates diet-induced atherosclerosis development. Initial studies suggest that BAT activation in humans may also reduce triglyceride and cholesterol levels, but potential antiatherogenic effects should be assessed in future studies. PMID:26837747

  5. LSD1 Interacts with Zfp516 to Promote UCP1 Transcription and Brown Fat Program

    OpenAIRE

    Audrey Sambeat; Olga Gulyaeva; Jon Dempersmier; Kevin M. Tharp; Andreas Stahl; Sarah M. Paul; Hei Sook Sul

    2016-01-01

    Zfp516, a brown fat (BAT)-enriched and cold-inducible transcription factor, promotes transcription of UCP1 and other BAT-enriched genes for non-shivering thermogenesis. Here, we identify lysine-specific demethylase 1 (LSD1) as a direct binding partner of Zfp516. We show that, through interaction with Zfp516, LSD1 is recruited to UCP1 and other BAT-enriched genes, such as PGC1α, to function as a coactivator by demethylating H3K9. We also show that LSD1 is induced during brown adipogenesis and ...

  6. A PGC1-α-dependent myokine that drives brown-fat-like development of white fat and thermogenesis

    DEFF Research Database (Denmark)

    Boström, Pontus; Wu, Jun; Jedrychowski, Mark P;

    2012-01-01

    FNDC5, a membrane protein that is cleaved and secreted as a newly identified hormone, irisin. Irisin acts on white adipose cells in culture and in vivo to stimulate UCP1 expression and a broad program of brown-fat-like development. Irisin is induced with exercise in mice and humans, and mildly...... increased irisin levels in the blood cause an increase in energy expenditure in mice with no changes in movement or food intake. This results in improvements in obesity and glucose homeostasis. Irisin could be therapeutic for human metabolic disease and other disorders that are improved with exercise....

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

    Science.gov (United States)

    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. PMID:26041126

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

    International Nuclear Information System (INIS)

    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 [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 10-5 M) suggesting predominate beta2-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-2-type BAR coupled to adenylate cyclase in rat brown fat

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

    Energy Technology Data Exchange (ETDEWEB)

    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.

  10. Assessment of oxidative metabolism in Brown Fat using PET imaging

    Directory of Open Access Journals (Sweden)

    Otto eMuzik

    2012-02-01

    Full Text Available Objective: Although it has been believed that brown adipose tissue (BAT depots disappear shortly after the perinatal period in humans, PET imaging using the glucose analog FDG has shown unequivocally the existence of functional BAT in humans. The objective of this study was to determine, using dynamic oxygen-15 (15O PET imaging, to what extent BAT thermogenesis is activated in adults during cold stress and to establish the relationship between BAT oxidative metabolism and FDG tracer uptake.Methods: Fourteen adult normal subjects (9F/5M, 30+7 years underwent triple oxygen scans (H215O, C15O, 15O2 as well as indirect calorimetric measurements at rest and following exposure to mild cold (60F. Subjects were divided into two groups (BAT+ and BAT- based on the presence or absence of FDG tracer uptake (SUV > 2 in supraclavicular BAT. Blood flow (BF and oxygen extraction fraction (OEF was calculated from dynamic PET scans at the location of BAT, muscle and white adipose tissue (WAT. The metabolic rate of oxygen (MRO2 in BAT was determined and used to calculate the contribution of activated BAT to daily energy expenditure (DEE.Results: The median mass of activated BAT in the BAT+ group (5F, 31+8yrs was 52.4 g (14-68g and was 1.7 g (0-6.3g in the BAT- group (5M/4F, 29+6yrs. SUV values were significantly higher in the BAT+ as compared to the BAT- group (7.4+3.7 vs 1.9+0.9; p=0.03. BF values in BAT were significantly higher in the BAT+ as compared to the BAT- group (13.1+4.4 vs 5.7+1.1 ml/100g/min, p=0.03, but were similar in WAT (4.1+1.6 vs 4.2+1.8 ml/100g/min and muscle (3.7+0.8 vs 3.3+1.2 ml/100g/min. Calculated MRO2 values in BAT increased from 0.95+0.74 to 1.62+0.82 ml/100g/min in the BAT+ group and were significantly higher than those determined in the BAT- group (0.43+0.27 vs 0.56+0.24; p=0.67. The DEE associated with BAT oxidative metabolism was highly variable in the BAT+ group, with an average of 5.5+6.4 kcal/day (range 0.57–15.3 kcal/day.

  11. Genetic Manipulation of Brown Fat Via Oral Administration of an Engineered Recombinant Adeno-associated Viral Serotype Vector.

    Science.gov (United States)

    Huang, Wei; McMurphy, Travis; Liu, Xianglan; Wang, Chuansong; Cao, Lei

    2016-06-01

    Recombinant adeno-associated virus (rAAV) vectors are attractive vehicles for gene therapy. Gene delivery to the adipose tissue using naturally occurring AAV serotypes is less successful compared to liver and muscle. Here, we demonstrate that oral administration of an engineered serotype Rec2 led to preferential transduction of brown fat with absence of transduction in the gastrointestinal track. Among the six natural and engineered serotypes being compared, Rec2 was the most efficient serotype achieving high level transduction at a dose 1~2 orders lower than reported doses for systemic administration. Overexpressing vascular endothelial growth factor (VEGF) in brown fat via oral administration of Rec2-VEGF vector increased the brown fat mass and enhanced thermogenesis. In contrast, knockdown VEGF in brown fat of VEGF (loxP) mice via Rec2-Cre vector hampered cold response and decreased brown fat mass. Oral administration of Rec2 vector provides a novel tool to genetically manipulate brown fat for research and therapeutic applications. PMID:26857843

  12. Brown adipose tissue quantification in human neonates using water-fat separated MRI.

    Directory of Open Access Journals (Sweden)

    Jerod M Rasmussen

    Full Text Available There is a major resurgence of interest in brown adipose tissue (BAT biology, particularly regarding its determinants and consequences in newborns and infants. Reliable methods for non-invasive BAT measurement in human infants have yet to be demonstrated. The current study first validates methods for quantitative BAT imaging of rodents post mortem followed by BAT excision and re-imaging of excised tissues. Identical methods are then employed in a cohort of in vivo infants to establish the reliability of these measures and provide normative statistics for BAT depot volume and fat fraction. Using multi-echo water-fat MRI, fat- and water-based images of rodents and neonates were acquired and ratios of fat to the combined signal from fat and water (fat signal fraction were calculated. Neonatal scans (n = 22 were acquired during natural sleep to quantify BAT and WAT deposits for depot volume and fat fraction. Acquisition repeatability was assessed based on multiple scans from the same neonate. Intra- and inter-rater measures of reliability in regional BAT depot volume and fat fraction quantification were determined based on multiple segmentations by two raters. Rodent BAT was characterized as having significantly higher water content than WAT in both in situ as well as ex vivo imaging assessments. Human neonate deposits indicative of bilateral BAT in spinal, supraclavicular and axillary regions were observed. Pairwise, WAT fat fraction was significantly greater than BAT fat fraction throughout the sample (ΔWAT-BAT = 38 %, p<10(-4. Repeated scans demonstrated a high voxelwise correlation for fat fraction (Rall = 0.99. BAT depot volume and fat fraction measurements showed high intra-rater (ICCBAT,VOL = 0.93, ICCBAT,FF = 0.93 and inter-rater reliability (ICCBAT,VOL = 0.86, ICCBAT,FF = 0.93. This study demonstrates the reliability of using multi-echo water-fat MRI in human neonates for quantification throughout the torso of BAT depot volume and fat

  13. Ablation of NG2 proteoglycan leads to deficits in brown fat function and to adult onset obesity.

    Directory of Open Access Journals (Sweden)

    Yunchao Chang

    Full Text Available Obesity is a major health problem worldwide. We are studying the causes and effects of obesity in C57Bl/6 mice following genetic ablation of NG2, a chondroitin sulfate proteoglycan widely expressed in progenitor cells and also in adipocytes. Although global NG2 ablation delays early postnatal adipogenesis in mouse skin, adult NG2 null mice are paradoxically heavier than wild-type mice, exhibiting larger white fat deposits. This adult onset obesity is not due to NG2-dependent effects on CNS function, since specific ablation of NG2 in oligodendrocyte progenitors yields the opposite phenotype; i.e. abnormally lean mice. Metabolic analysis reveals that, while activity and food intake are unchanged in global NG2 null mice, O(2 consumption and CO(2 production are decreased, suggesting a decrease in energy expenditure. Since brown fat plays important roles in regulating energy expenditure, we have investigated brown fat function via cold challenge and high fat diet feeding, both of which induce the adaptive thermogenesis that normally occurs in brown fat. In both tests, body temperatures in NG2 null mice are reduced compared to wild-type mice, indicating a deficit in brown fat function in the absence of NG2. In addition, adipogenesis in NG2 null brown pre-adipocytes is dramatically impaired compared to wild-type counterparts. Moreover, mRNA levels for PR domain containing 16 (PRDM16 and peroxisome proliferator-activated receptor γ coactivator (PGC1-α, proteins important for brown adipocyte differentiation, are decreased in NG2 null brown fat deposits in vivo and NG2 null brown pre-adipocytes in vitro. Altogether, these results indicate that brown fat dysfunction in NG2 null mice results from deficits in the recruitment and/or development of brown pre-adipocytes. As a consequence, obesity in NG2 null mice may occur due to disruptions in brown fat-dependent energy homeostasis, with resulting effects on lipid storage in white adipocytes.

  14. Fat deposition and flesh quality in seawater reared, triploid brown trout (Salmo trutta) as affected by dietary fat levels and starvation

    OpenAIRE

    Regost, Christelle; Arzel, Jacqueline; Cardinal, Mireille; Laroche, M; Kaushik, Sadasivam

    2001-01-01

    Three isoproteic (crude protein content: 56%) diets with different fat levels (11%, 20%, and 26%) were fed to triplicate groups of triploid brown trout (initial average body weight of 1.5 kg), reared in seawater. At the end of 3 months of feeding, fish fed the high-fat (HF) diet were split into two groups: a triplicate group of fish received the low-fat diet and another triplicate group was kept unfed for a further 2-month period. Fish initially fed the low-fat diet during the first period we...

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

    Science.gov (United States)

    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

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

    Directory of Open Access Journals (Sweden)

    Vibha Singhal

    Full Text Available 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.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.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.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.Our study shows a trend for lower BAT in young female

  17. Regulation of brown fat adipogenesis by protein tyrosine phosphatase 1B.

    Directory of Open Access Journals (Sweden)

    Kosuke Matsuo

    Full Text Available Protein-tyrosine phosphatase 1B (PTP1B is a physiological regulator of insulin signaling and energy balance, but its role in brown fat adipogenesis requires additional investigation.To precisely determine the role of PTP1B in adipogenesis, we established preadipocyte cell lines from wild type and PTP1B knockout (KO mice. In addition, we reconstituted KO cells with wild type, substrate-trapping (D/A and sumoylation-resistant (K/R PTP1B mutants, then characterized differentiation and signaling in these cells. KO, D/A- and WT-reconstituted cells fully differentiated into mature adipocytes with KO and D/A cells exhibiting a trend for enhanced differentiation. In contrast, K/R cells exhibited marked attenuation in differentiation and lipid accumulation compared with WT cells. Expression of adipogenic markers PPARγ, C/EBPα, C/EBPδ, and PGC1α mirrored the differentiation pattern. In addition, the differentiation deficit in K/R cells could be reversed completely by the PPARγ activator troglitazone. PTP1B deficiency enhanced insulin receptor (IR and insulin receptor substrate 1 (IRS1 tyrosyl phosphorylation, while K/R cells exhibited attenuated insulin-induced IR and IRS1 phosphorylation and glucose uptake compared with WT cells. In addition, substrate-trapping studies revealed that IRS1 is a substrate for PTP1B in brown adipocytes. Moreover, KO, D/A and K/R cells exhibited elevated AMPK and ACC phosphorylation compared with WT cells.These data indicate that PTP1B is a modulator of brown fat adipogenesis and suggest that adipocyte differentiation requires regulated expression of PTP1B.

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

    OpenAIRE

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

    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/B...

  19. Inherent Plasticity of Brown Adipogenesis in White Fat of Mice Allows for Recovery from Effects of Post-Natal Malnutrition

    OpenAIRE

    Kozak, Leslie P.; Koza, Robert A.; Anunciado-Koza, Rea; Mendoza, Tamra; Newman, Susan

    2012-01-01

    Interscapular brown adipose tissue (iBAT) is formed during fetal development and stable for the life span of the mouse. In addition, brown adipocytes also appear in white fat depots (wBAT) between 10 and 21 days of age in mice maintained at a room temperature of 23°C. However, this expression is transient. By 60 days of age the brown adipocytes have disappeared, but they can re-emerge if the adult mouse is exposed to the cold (5°C) or treated with β3-adrenergic agonists. Since the number of b...

  20. Can brown fat uptake of 18F-FDG be reduced by beta-blockers?

    International Nuclear Information System (INIS)

    With the increasing application of F-18-fluorodeoxyglucose (FDG) positron emission imaging, there has been an evolving appreciation for the range of normal variants and the realization that false- positives can lead to serious consequences. One of the most common causes of a false-positive study is the uptake of FDG in areas of brown adipose tissue. BAT is generally present in deep cervical regions, including the supraclavicular areas, the interscapular and paravertebral regions, and areas near large vessels. Areas of involvement are often spatially closely related to important lymph node groups in the neck, axilla, and upper mediastinum, making critical differentiation difficult. The uptake of 18F FDG in brown adipose tissue (BAT) limits the ability of a PET scan to detect the sites of viable disease. Many studies have been done after premedication with Diazepam (benzodiazepines) to reduce the uptake of FDG by brown fat. But they are of limited value. Thus, it would be ideal if a drug could completely reverse the brown fat uptake and thus aid in proper management of the patient. The aim of this study is to see if by giving a single dose of a beta-blocker such as 'Ciplar' (Propranolol) 40 mg, 30 minutes prior to the FDG injection will help in reduction of brown fat uptake of 18F-FDG or not. Materials and Methods: Patients who were referred for a PET scan, either for a pretreatment or a post treatment evaluation and who showed FDG uptake in brown adipose tissue (BAT) were taken up for this study. The total number of patients was 14. A repeat PET scan was done after a gap of at least 48 hrs after the first study. The patients were advised to keep themselves warm with adequate warm clothing on the day of the second study. 40 mg of 'Ciplar' (propranolol) was given orally 30 minutes prior to the 18F-FDG injection. A whole body PET scan was performed on a dedicated whole body PET scanner (ADVANCE, GE Medical Systems, Milwaukee, WI.), using attenuation correction with 68

  1. LSD1 Interacts with Zfp516 to Promote UCP1 Transcription and Brown Fat Program

    Directory of Open Access Journals (Sweden)

    Audrey Sambeat

    2016-06-01

    Full Text Available Zfp516, a brown fat (BAT-enriched and cold-inducible transcription factor, promotes transcription of UCP1 and other BAT-enriched genes for non-shivering thermogenesis. Here, we identify lysine-specific demethylase 1 (LSD1 as a direct binding partner of Zfp516. We show that, through interaction with Zfp516, LSD1 is recruited to UCP1 and other BAT-enriched genes, such as PGC1α, to function as a coactivator by demethylating H3K9. We also show that LSD1 is induced during brown adipogenesis and that LSD1 and its demethylase activity is required for the BAT program. Furthermore, we show that LSD1 ablation in mice using Myf5-Cre alters embryonic BAT development. Moreover, BAT-specific deletion of LSD1 via the use of UCP1-Cre impairs the BAT program and BAT development, making BAT resemble WAT, reducing thermogenic activity and promoting obesity. Finally, we demonstrate an in vivo requirement of the Zfp516-LSD1 interaction for LSD1 function in BAT gene activation.

  2. LSD1 Interacts with Zfp516 to Promote UCP1 Transcription and Brown Fat Program.

    Science.gov (United States)

    Sambeat, Audrey; Gulyaeva, Olga; Dempersmier, Jon; Tharp, Kevin M; Stahl, Andreas; Paul, Sarah M; Sul, Hei Sook

    2016-06-14

    Zfp516, a brown fat (BAT)-enriched and cold-inducible transcription factor, promotes transcription of UCP1 and other BAT-enriched genes for non-shivering thermogenesis. Here, we identify lysine-specific demethylase 1 (LSD1) as a direct binding partner of Zfp516. We show that, through interaction with Zfp516, LSD1 is recruited to UCP1 and other BAT-enriched genes, such as PGC1α, to function as a coactivator by demethylating H3K9. We also show that LSD1 is induced during brown adipogenesis and that LSD1 and its demethylase activity is required for the BAT program. Furthermore, we show that LSD1 ablation in mice using Myf5-Cre alters embryonic BAT development. Moreover, BAT-specific deletion of LSD1 via the use of UCP1-Cre impairs the BAT program and BAT development, making BAT resemble WAT, reducing thermogenic activity and promoting obesity. Finally, we demonstrate an in vivo requirement of the Zfp516-LSD1 interaction for LSD1 function in BAT gene activation. PMID:27264172

  3. Medium-Chain Triglyceride Activated Brown Adipose Tissue and Induced Reduction of Fat Mass in C57BL/6J Mice Fed High-fat Diet

    Institute of Scientific and Technical Information of China (English)

    ZHANG Yong; XUE Chang Yong; XU Qing; LIU Ying Hua; ZHANG Xin Sheng; WANG Jin; YU Xiao Ming; ZHANG Rong Xin; XUE Chao; YANG Xue Yan

    2015-01-01

    Objective To investigate activation of brown adipose tissue (BAT) stimulated by medium-chain triglyceride (MCT). Methods 30 Male C57BL/6J obese mice induced by fed high fat diet (HFD) were divided into 2 groups, and fed another HFD with 2% MCT or long-chain triglyceride (LCT) respectively for 12 weeks. Body weight, blood biochemical variables, interscapular brown fat tissue (IBAT) mass, expressions of mRNA and protein of beta 3-adrenergic receptors (β3-AR), uncoupling protein-1 (UCP1), hormone sensitive lipase (HSL), protein kinase A (PKA), and adipose triglyceride lipase (ATGL) in IBAT were measured. Results Significant decrease in body weight and body fat mass was observed in MCT group as compared with LCT group (P<0.05) after 12 weeks. Greater increases in IBAT mass was observed in MCT group than in LCT group (P<0.05). Blood TG, TC, LDL-C in MCT group were decreased significantly, meanwhile blood HDL-C, ratio of HDL-C/LDL-C and norepinephrine were increased markedly. Expressions of mRNA and protein ofβ3-AR, UCP1, PKA, HSL, ATGL in BAT were greater in MCT group than in LCT group (P<0.05). Conclusion Our results suggest that MCT stimulated the activation of BAT, possible via norepinephrine pathway, which might partially contribute to reduction of the body fat mass in obese mice fed high fat diet.

  4. Brown fat distribution in the chest wall of infants - normal appearance, distribution and evolution on CT scans of the chest

    International Nuclear Information System (INIS)

    While reviewing chest CT scans of infants, we repeatedly observed hyperdense enhancing tissue in the chest wall that is not well described in radiology literature. This study was undertaken to describe the imaging features of this tissue in chest walls of infants. CT scans of the chest conducted on all infants between April 2008 and October 2009 were retrospectively reviewed. CT studies with any deviation from normal radiation or contrast dose or those with chest wall anatomical distortion were excluded. One hundred eighty-eight infants were scanned, with 202 MDCTs, of which 180 (89.1%) received contrast agent. Fifty-four of 180 (30%) cases revealed focal areas of hyperdensity in various locations. All positive cases ranged between 2 days and 9 months of age. The areas of distribution of hyperdensity had excellent correlation with known areas of brown fat in the chest wall, known from nuclear medicine studies, and hence we concluded these to represent the same. Brown fat in the chest wall can be seen as enhancing tissue on contrast CT scans done on infants. This is a normal morphological component with the brown fat converting to normal fat. It is important to recognize it in the chest wall of infants to avoid misinterpretation. (orig.)

  5. Ursolic acid increases skeletal muscle and brown fat and decreases diet-induced obesity, glucose intolerance and fatty liver disease.

    Directory of Open Access Journals (Sweden)

    Steven D Kunkel

    Full Text Available Skeletal muscle Akt activity stimulates muscle growth and imparts resistance to obesity, glucose intolerance and fatty liver disease. We recently found that ursolic acid increases skeletal muscle Akt activity and stimulates muscle growth in non-obese mice. Here, we tested the hypothesis that ursolic acid might increase skeletal muscle Akt activity in a mouse model of diet-induced obesity. We studied mice that consumed a high fat diet lacking or containing ursolic acid. In skeletal muscle, ursolic acid increased Akt activity, as well as downstream mRNAs that promote glucose utilization (hexokinase-II, blood vessel recruitment (Vegfa and autocrine/paracrine IGF-I signaling (Igf1. As a result, ursolic acid increased skeletal muscle mass, fast and slow muscle fiber size, grip strength and exercise capacity. Interestingly, ursolic acid also increased brown fat, a tissue that shares developmental origins with skeletal muscle. Consistent with increased skeletal muscle and brown fat, ursolic acid increased energy expenditure, leading to reduced obesity, improved glucose tolerance and decreased hepatic steatosis. These data support a model in which ursolic acid reduces obesity, glucose intolerance and fatty liver disease by increasing skeletal muscle and brown fat, and suggest ursolic acid as a potential therapeutic approach for obesity and obesity-related illness.

  6. Brown fat distribution in the chest wall of infants - normal appearance, distribution and evolution on CT scans of the chest

    Energy Technology Data Exchange (ETDEWEB)

    Gupta, Priya; Babyn, Paul S.; Shammas, Amer; Miller, Stephen F. [Hospital for Sick Children, Department of Diagnostic Imaging, Toronto (Canada)

    2011-08-15

    While reviewing chest CT scans of infants, we repeatedly observed hyperdense enhancing tissue in the chest wall that is not well described in radiology literature. This study was undertaken to describe the imaging features of this tissue in chest walls of infants. CT scans of the chest conducted on all infants between April 2008 and October 2009 were retrospectively reviewed. CT studies with any deviation from normal radiation or contrast dose or those with chest wall anatomical distortion were excluded. One hundred eighty-eight infants were scanned, with 202 MDCTs, of which 180 (89.1%) received contrast agent. Fifty-four of 180 (30%) cases revealed focal areas of hyperdensity in various locations. All positive cases ranged between 2 days and 9 months of age. The areas of distribution of hyperdensity had excellent correlation with known areas of brown fat in the chest wall, known from nuclear medicine studies, and hence we concluded these to represent the same. Brown fat in the chest wall can be seen as enhancing tissue on contrast CT scans done on infants. This is a normal morphological component with the brown fat converting to normal fat. It is important to recognize it in the chest wall of infants to avoid misinterpretation. (orig.)

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

    Science.gov (United States)

    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

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

    Directory of Open Access Journals (Sweden)

    Chi H. L. Dinh

    2015-06-01

    Full Text Available 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.

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

    Science.gov (United States)

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

    2015-06-01

    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

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

    OpenAIRE

    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

    2013-01-01

    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 BMP...

  11. Isoenergetic Feeding of Low Carbohydrate-High Fat Diets Does Not Increase Brown Adipose Tissue Thermogenic Capacity in Rats

    OpenAIRE

    Betz, Matthias J.; Maximilian Bielohuby; Brigitte Mauracher; William Abplanalp; Hans-Helge Müller; Korbinian Pieper; Juliane Ramisch; Tschöp, Matthias H.; Felix Beuschlein; Martin Bidlingmaier; Marc Slawik

    2012-01-01

    UNLABELLED: Low-carbohydrate, high-fat (LC-HF) diets are popular for inducing weight loss in overweighed adults. Adaptive thermogenesis increased by specific effects of macronutrients on energy expenditure has been postulated to induce this weight loss. We studied brown adipose tissue (BAT) morphology and function following exposure to different LC-HF diets. METHODS: Male Wistar rats were fed a standard control diet ad libitum or pair-fed isoenergetic amounts of three experimental diets for 4...

  12. Isoenergetic feeding of low carbohydrate-high fat diets does not increase brown adipose tissue thermogenic capacity in rats

    OpenAIRE

    Betz, Matthias J.; Bielohuby, Maximilian; Mauracher, Brigitte; Abplanalp, William; Müller, Hans-Helge; Pieper, Korbinian; Ramisch, Juliane; Tschöp, Matthias H.; Beuschlein, Felix; Bidlingmaier, Martin; Slawik, Marc

    2012-01-01

    Low-carbohydrate, high-fat (LC-HF) diets are popular for inducing weight loss in overweighed adults. Adaptive thermogenesis increased by specific effects of macronutrients on energy expenditure has been postulated to induce this weight loss. We studied brown adipose tissue (BAT) morphology and function following exposure to different LC-HF diets. Methods: Male Wistar rats were fed a standard control diet ad libitum or pair-fed isoenergetic amounts of three experimental diets for 4 weeks...

  13. 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

    Science.gov (United States)

    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...

  14. Adipose VEGF Links the White-to-Brown Fat Switch With Environmental, Genetic, and Pharmacological Stimuli in Male Mice.

    Science.gov (United States)

    During, Matthew J; Liu, Xianglan; Huang, Wei; Magee, Daniel; Slater, Andrew; McMurphy, Travis; Wang, Chuansong; Cao, Lei

    2015-06-01

    Living in an enriched environment (EE) decreases adiposity, increases energy expenditure, causes resistance to diet induced obesity, and induces brown-like (beige) cells in white fat via activating a hypothalamic-adipocyte axis. Here we report that EE stimulated vascular endothelial growth factor (VEGF) expression in a fat depot-specific manner prior to the emergence of beige cells. The VEGF up-regulation was independent of hypoxia but required intact sympathetic tone to the adipose tissue. Targeted adipose overexpression of VEGF reproduced the browning effect of EE. Adipose-specific VEGF knockout or pharmacological VEGF blockade with antibodies abolished the induction of beige cell by EE. Hypothalamic brain-derived neurotrophic factor stimulated by EE regulated the adipose VEGF expression, and VEGF signaling was essential to the hypothalamic brain-derived neurotrophic factor-induced white adipose tissue browning. Furthermore, VEGF signaling was essential to the beige cells induction by exercise, a β3-adrenergic agonist, and a peroxisome proliferator-activated receptor-γ ligand, suggesting a common downstream pathway integrating diverse upstream mechanisms. Exploiting this pathway may offer potential therapeutic interventions to obesity and metabolic diseases. PMID:25763639

  15. Direct evidence of brown adipocytes in different fat depots in children

    OpenAIRE

    Rockstroh, Denise; Landgraf, Kathrin; Wagner, Isabel Viola; Gesing, Julia; Tauscher, Roy; Lakowa, Nicole; Kiess, Wieland; Bühligen, Ulf; Wojan, Magdalena; Till, Holger; Blüher, Matthias; Körner, Antje

    2015-01-01

    Recent studies suggested the persistence of brown adipocytes in adult humans, as opposed to being exclusively present in infancy. In this study, we investigated the presence of brown-like adipocytes in adipose tissue (AT) samples of children and adolescents aged 0 to 18 years and evaluated the association with age, location, and obesity. For this, we analysed AT samples from 131 children and 23 adults by histological, immunohistochemical and expression analyses. We detected brown-like and UCP...

  16. 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.

    Science.gov (United States)

    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. PMID:27384013

  17. Central serotonergic neurons activate and recruit thermogenic brown and beige fat and regulate glucose and lipid homeostasis

    DEFF Research Database (Denmark)

    McGlashon, Jacob M; Gorecki, Michelle C; Kozlowski, Amanda E;

    2015-01-01

    diphtheria toxin receptor (DTR) was selectively expressed in central 5-HT neurons. Treatment with diphtheria toxin (DT) eliminated 5-HT neurons and caused loss of thermoregulation, brown adipose tissue (BAT) steatosis, and a >50% decrease in uncoupling protein 1 (Ucp1) expression in BAT and inguinal white...... adipose tissue (WAT). In parallel, blood glucose increased 3.5-fold, free fatty acids 13.4-fold, and triglycerides 6.5-fold. Similar BAT and beige fat defects occurred in Lmx1b(f/f)ePet1(Cre) mice in which 5-HT neurons fail to develop in utero. We conclude 5-HT neurons play a major role in regulating...

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

    OpenAIRE

    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 adequ...

  19. Direct evidence of brown adipocytes in different fat depots in children.

    Directory of Open Access Journals (Sweden)

    Denise Rockstroh

    Full Text Available Recent studies suggested the persistence of brown adipocytes in adult humans, as opposed to being exclusively present in infancy. In this study, we investigated the presence of brown-like adipocytes in adipose tissue (AT samples of children and adolescents aged 0 to 18 years and evaluated the association with age, location, and obesity. For this, we analysed AT samples from 131 children and 23 adults by histological, immunohistochemical and expression analyses. We detected brown-like and UCP1 positive adipocytes in 10.3% of 87 lean children (aged 0.3 to 10.7 years and in one overweight infant, whereas we did not find brown adipocytes in obese children or adults. In our samples, the brown-like adipocytes were interspersed within white AT of perirenal, visceral and also subcutaneous depots. Samples with brown-like adipocytes showed an increased expression of UCP1 (>200fold, PRDM16 (2.8fold, PGC1α and CIDEA while other brown/beige selective markers, such as PAT2, P2RX5, ZIC1, LHX8, TMEM26, HOXC9 and TBX1 were not significantly different between UCP1 positive and negative samples. We identified a positive correlation between UCP1 and PRDM16 within UCP1 positive samples, but not with any other brown/beige marker. In addition, we observed significantly increased PRDM16 and PAT2 expression in subcutaneous and visceral AT samples with high UCP1 expression in adults. Our data indicate that brown-like adipocytes are present well beyond infancy in subcutaneous depots of non-obese children. The presence was not restricted to typical perirenal locations, but they were also interspersed within WAT of visceral and subcutaneous depots.

  20. (11)C-meta-hydroxyephedrine PET/CT imaging allows in vivo study of adaptive thermogenesis and white-to-brown fat conversion

    OpenAIRE

    Quarta, C.; F. Lodi; Mazza, R; Giannone, F; Boschi, L.; Nanni, C; E. Nisoli; Boschi, S; Pasquali, R.; Fanti, S.; P. Iozzo; Pagotto, U.

    2013-01-01

    Several lines of evidence suggest that novel pharmacological approaches aimed at converting white adipose tissue (WAT) into brown adipose tissue (BAT) may represent an effective therapeutic strategy for obesity and related disorders. (18)F-fluorodeoxyglucose (18F-FDG) is the only positron emission tomography (PET) tracer commonly used to study BAT function, and so far no functional tools have been described to investigate in vivo white-to-brown fat conversion. In this report, we show that the...

  1. Isoenergetic feeding of low carbohydrate-high fat diets does not increase brown adipose tissue thermogenic capacity in rats.

    Directory of Open Access Journals (Sweden)

    Matthias J Betz

    Full Text Available UNLABELLED: Low-carbohydrate, high-fat (LC-HF diets are popular for inducing weight loss in overweighed adults. Adaptive thermogenesis increased by specific effects of macronutrients on energy expenditure has been postulated to induce this weight loss. We studied brown adipose tissue (BAT morphology and function following exposure to different LC-HF diets. METHODS: Male Wistar rats were fed a standard control diet ad libitum or pair-fed isoenergetic amounts of three experimental diets for 4 weeks. The diets had the following macronutrient composition (% metabolizable energy: carbohydrates, fat, protein: control (64.3/16.7/19, LC-HF-low protein (LC-HF-LP, 1.7/92.8/5.5, LC-HF-normal-protein (LC-HF-NP, 2.2/78.7/19.1, and a high fat diet with carbohydrates ("high fat", 19.4/61.9/18.7. RESULTS: Body weight gain was reduced in all pair-fed experimental groups as compared to rats fed the control diet, with more pronounced effect in rats on LC-HF diets than on the high fat diet with carbohydrates. High fat diets increased expression of PGC1α and ADRB3 in BAT indicating higher SNS outflow. However, UCP1 mRNA expression and expression of UCP1 assessed by immunohistochemistry was not different between diet groups. In accordance, analysis of mitochondrial function in-vitro by extracellular flux analyser (Seahorse Bioscience and measurement of inducible thermogenesis in vivo (primary endpoint, explored by indirect calorimetry following norepinephrine injection, did not show significant differences between groups. Histology of BAT revealed increased lipid droplet size in rats fed the high-fat diet and both LC-HF diets. CONCLUSION: All experimental diets upregulated expression of genes which are indicative for increased BAT activity. However, the functional measurements in vivo revealed no increase of inducible BAT thermogenesis. This indicates that lower body weight gain with LC-HF diets and a high fat diet in a pair-feeding setting is not caused by

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

    Science.gov (United States)

    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

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

    Science.gov (United States)

    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

  4. Biodegradable polymeric microsphere-based drug delivery for inductive browning of fat

    Directory of Open Access Journals (Sweden)

    Chunhui eJiang

    2015-11-01

    Full Text Available 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 (WAT 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.

  5. Radioimmunoassay method for triiodothyronine and thyroxine

    International Nuclear Information System (INIS)

    This invention relates to a radioimmunoassay method for triiodothyronine or thyroxine or triiodothyronine and thyroxine present in unextracted serum containing thyroxine binding prealbumin and thyroxine binding globulin. Procedures using 125I and 131I are described

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

    Science.gov (United States)

    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...

  7. A high-fat diet impairs cooling-evoked brown adipose tissue activation via a vagal afferent mechanism.

    Science.gov (United States)

    Madden, Christopher J; Morrison, Shaun F

    2016-08-01

    In dramatic contrast to rats on a control diet, rats maintained on a high-fat diet (HFD) failed to activate brown adipose tissue (BAT) during cooling despite robust increases in their BAT activity following direct activation of their BAT sympathetic premotor neurons in the raphe pallidus. Cervical vagotomy or blockade of glutamate receptors in the nucleus of the tractus solitarii (NTS) reversed the HFD-induced inhibition of cold-evoked BAT activity. Thus, a HFD does not prevent rats from mounting a robust, centrally driven BAT thermogenesis; however, a HFD does alter a vagal afferent input to NTS neurons, thereby preventing the normal activation of BAT thermogenesis to cooling. These results, paralleling the absence of cooling-evoked glucose uptake in the BAT of obese humans, reveal a neural mechanism through which consumption of a HFD contributes to reduced energy expenditure and thus to weight gain. PMID:27354235

  8. Lithium and methylphenidate: opposite effects on perirenal brown fat Lítio e metilfenidato: efeitos opostos sobre a gordura perirrenal

    Directory of Open Access Journals (Sweden)

    José Menna Oliveira

    2010-01-01

    Full Text Available OBJECTIVE: To evaluate the effects of the administration of lithium to adult rats on brown (perirenal and white (inguinal adipose tissues and to assess whether methylphenidate modulates lithium effects. METHODS: Twenty-five adult male Wistar rats were fed with either regular or lithium-containing chow for 30 days. Between days 15 to 30 of treatment, animals received daily intraperitoneal administrations of either methylphenidate or saline. RESULTS: Lithium significantly reduced perirenal fat, and this effect was minimized by the administration of methylphenidate. There were no significant differences between the groups in terms of the effects of lithium on inguinal fat. CONCLUSION: Our findings suggest that different effects on white and brown tissue distribution may be involved in lithium-induced weight gain.OBJETIVO: Avaliar como a administração de lítio afeta o tecido adiposo marrom (perirrenal e branco (inguinal e se o metilfenidato modula os efeitos do lítio. MÉTODOS: Vinte e cinco ratos Wistar adultos machos foram alimentados com ração normal ou contendo lítio por 30 dias. Entre os dias 15 e 30 de tratamento, os animais receberam doses intraperitoneais diárias de metilfenidato ou solução salina. RESULTADOS: A administração de lítio reduziu significativamente a gordura perirrenal. Esse efeito foi reduzido com a administração de metilfenidato. Não houve diferenças significativas entre os grupos em relação à gordura inguinal. CONCLUSÃO: Os achados sugerem que efeitos diferenciados sobre os tecidos adiposos marrom e branco podem estar envolvidos no ganho de peso induzido pelo tratamento com lítio.

  9. Hedgehog partial agonism drives Warburg-like metabolism in muscle and brown fat

    DEFF Research Database (Denmark)

    Teperino, Raffaele; Amann, Sabine; Bayer, Martina;

    2012-01-01

    Diabetes, obesity, and cancer affect upward of 15% of the world's population. Interestingly, all three diseases juxtapose dysregulated intracellular signaling with altered metabolic state. Exactly which genetic factors define stable metabolic set points in vivo remains poorly understood. Here, we......-independent glucose uptake in muscle and brown adipose tissue. These data identify multiple noncanonical endpoints that are pivotal for rational design of hedgehog modulators and provide a new therapeutic avenue for obesity and diabetes....

  10. Shc depletion stimulates brown fat activity in vivo and in vitro

    OpenAIRE

    Tomilov, Alexey; Bettaieb, Ahmed; Kim, Kyoungmi; Sahdeo, Sunil; Tomilova, Natalia; Lam, Adam; Hagopian, Kevork; Connell, Michelle; Fong, Jennifer; Rowland, Douglas; Griffey, Stephen; Ramsey, Jon; Haj, Fawaz; Cortopassi, Gino

    2014-01-01

    Adipose tissue is an important metabolic organ that integrates a wide array of homeostatic processes and is crucial for whole-body insulin sensitivity and energy metabolism. Brown adipose tissue (BAT) is a key thermogenic tissue with a well-established role in energy expenditure. BAT dissipates energy and protects against both hypothermia and obesity. Thus, BAT stimulation therapy is a rational strategy for the looming pandemic of obesity, whose consequences and comorbidities have a huge impa...

  11. Hypothalamic GLP-1: the control of BAT thermogenesis and browning of white fat

    OpenAIRE

    López, Miguel; Diéguez, Carlos; Nogueiras, Rubén

    2015-01-01

    Brown adipose tissue (BAT) is a specialized organ responsible for thermogenesis, a process required for maintaining body temperature. Since the discovery that BAT and brite/beige cells are functional in adult humans, many studies have been focusing on the physiology and functionality of this organ. The brain is controlling the maintenance of body temperature through a complex neuronal network. One of the candidates to modulate thermogenesis at central level is glucagon-like peptide-1 (GLP-1),...

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

    Science.gov (United States)

    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

  13. Thermogenic capacity is antagonistically regulated in classical brown and white subcutaneous fat depots by high fat diet and endurance training in rats: impact on whole-body energy expenditure.

    Science.gov (United States)

    Wu, Michelle V; Bikopoulos, George; Hung, Steven; Ceddia, Rolando B

    2014-12-01

    This study investigated the regulation of thermogenic capacity in classical brown adipose tissue (BAT) and subcutaneous inguinal (SC Ing) white adipose tissue (WAT) and how it affects whole-body energy expenditure in sedentary and endurance-trained rats fed ad libitum either low fat or high fat (HF) diets. Analysis of tissue mass, PGC-1α and UCP-1 content, the presence of multilocular adipocytes, and palmitate oxidation revealed that a HF diet increased the thermogenic capacity of the interscapular and aortic brown adipose tissues, whereas exercise markedly suppressed it. Conversely, exercise induced browning of the SC Ing WAT. This effect was attenuated by a HF diet. Endurance training neither affected skeletal muscle FNDC5 content nor circulating irisin, but it increased FNDC5 content in SC Ing WAT. This suggests that locally produced FNDC5 rather than circulating irisin mediated the exercise-induced browning effect on this fat tissue. Importantly, despite reducing the thermogenic capacity of classical BAT, exercise increased whole-body energy expenditure during the dark cycle. Therefore, browning of subcutaneous WAT likely exerted a compensatory effect and raised whole-body energy expenditure in endurance-trained rats. Based on these novel findings, we propose that exercise-induced browning of the subcutaneous WAT provides an alternative mechanism that reduces thermogenic capacity in core areas and increases it in peripheral body regions. This could allow the organism to adjust its metabolic rate to accommodate diet-induced thermogenesis while simultaneously coping with the stress of chronically increased heat production through exercise. PMID:25344623

  14. Fatness

    DEFF Research Database (Denmark)

    Hansen, Anne Katrine Kleberg

    In 1727, the English physician Thomas Short wrote: “I believe no Age did ever afford more instances of Corpulency than our own.” Even in the 18th century, fatness was addressed as an issue of special contemporary concern. This thesis probes concepts and perceptions of fatness in Western European...... Medicine c. 1700–1900. It has been written with particular attention to whether and how fatness has been regarded as a disease during that period in history. One purpose of the thesis is to investigate the immediate period before fatness allegedly became problematized. Another purpose has been to grasp...

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

    Science.gov (United States)

    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.

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

    Energy Technology Data Exchange (ETDEWEB)

    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.

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

    International Nuclear Information System (INIS)

    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 [3H]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 [3H]GDP binding, characteristically observed with rat mitochondria, was not observed with hamster mitochondria, and the increase in [3H]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- 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

  18. Leucine Deprivation Decreases Fat Mass by Stimulation of Lipolysis in White Adipose Tissue and Upregulation of Uncoupling Protein 1 (UCP1) in Brown Adipose Tissue

    OpenAIRE

    Ying CHENG; Meng, Qingshu; Wang, Chunxia; Li, Houkai; Huang, Zhiying; Chen, Shanghai; Xiao, Fei; Guo, Feifan

    2009-01-01

    OBJECTIVE White adipose tissue (WAT) and brown adipose tissue (BAT) play distinct roles in adaptation to changes in nutrient availability, with WAT serving as an energy store and BAT regulating thermogenesis. We previously showed that mice maintained on a leucine-deficient diet unexpectedly experienced a dramatic reduction in abdominal fat mass. The cellular mechanisms responsible for this loss, however, are unclear. The goal of current study is to investigate possible mechanisms. RESEARCH DE...

  19. Reduction of the 18FDG uptake by the brown fat with the help of propranolol in a difficult case of lymphoma with residual disease suspicion

    International Nuclear Information System (INIS)

    The oncology group of the French Society of nuclear medicine implemented evaluation criteria of the lymphomas therapy response. The problem often encountered is this one of identification of minimum residual fixations in PET-F.D.G., considered as the residual disease in the non Hodgkin lymphomas. we report the case of a thirty four years old patient treated for diffuse at big B cells non Hodgkin lymphoma, in failure after the first line of treatment and with persistence of a hyper-metabolism in pre and post graft at the level of a para-cardiac residual mass. The post auto graft PET examination showed an important activation of the brown fat, able to question the origin of the residual para-cardiac hyper-metabolism in this dramatic situation, for a young patient and potentially still in therapy failure. In order to reduce the F.D.G. captation by the brown fat, it was proposed a new PET evaluation with propranolol administration (beta blocking) before the tracer injection. The intake of propranolol allowed to reduce in an important way, the F.D.G. captation by the brown fat, without modifying the residual hyper-metabolism. This result is going to lead to the realisation of a surgical biopsy. (N.C.)

  20. 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

    Energy Technology Data Exchange (ETDEWEB)

    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.

  1. 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

    International Nuclear Information System (INIS)

    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 3H2O 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

  2. The emergence of cold-induced brown adipocytes in mouse white fat depots is determined predominantly by white to brown adipocyte transdifferentiation

    DEFF Research Database (Denmark)

    Barbatelli, G.; Murano, I.; Madsen, Lise;

    2010-01-01

    The origin of brown adipocytes arising in white adipose tissue (WAT) after cold acclimatization is unclear. Here, we demonstrate that several UCP1-immunoreactive brown adipocytes occurring in WAT after cold acclimatization have a mixed morphology (paucilocular adipocytes). These cells also had a ...... for C/EBP (an antimitotic protein), whereas Ccna1 expression (related to cell proliferation) was unchanged. Overall, our data strongly suggest that the cold-induced emergence of brown adipocytes in WAT predominantly reflects ß3-adrenoceptor-mediated transdifferentiation....

  3. Free serum thyroxine

    International Nuclear Information System (INIS)

    The use of radiommunoassay (RIA) tehcniques has increased the diagnosis of thyroid functional alterations. A solid phase RIA method for free thyroxine (FT4) measurement was tested. Serum FT4, Total T4, T3 and TSH were determined by radioimmunoassay in 179 subjects. One hundred twenty two patients were normal (8 to 75 years old); FT4 was 1.42 +- 0.03 ng/100 ml (avg. value and std. error). In 27 cases of thyrotoxicosis the values were 4.66 +- 0.48 ng/100 ml and in 15 cases of hypothyroidism 0.50 +- 0.06 ng/100 ml (statistics probability <0,01). Four euthyroid patients under estrogen treatment, 9 hypothyroid patients under l-thyroxine treatment, one hyperthyroid patient under antithyroid drugs and one hyperthyroid patient under estrogen treatment, were studied. Total T4 and T3 values were in agreement with the variations of the serum protein transport capacity, and for that reason did not show the real thyroid function state. Clinical decision making analysis (with Receiver Operating Characteristic (ROC) curves) indicate that FT4 is the best choice for hyperthyroidism diagnosis and T4 for hypothyroidism. Cost/benefit analysis indicates also that FT4 has the best ratio. (author)

  4. THE TRANSCRIPTION FACTOR GATA2 REGULATES DIFFERENTIATION OF BROWN ADIPOCYTES

    Science.gov (United States)

    Brown fat tissue is functionally different than the white fat, since brown fat burns lipid to generate heat for body temperature maintenance. However, brown fat cells share with white fat cells a similar molecular mechanism for fat cell formation. We have demonstrated previously that the GATA family...

  5. Comparison of fatty acid, cholesterol, vitamin A and E composition, and trans fats in eggs from brown and white egg strains that were molted or nonmolted.

    Science.gov (United States)

    Anderson, Kenneth E

    2013-12-01

    The impact of egg color, hen strain, and molting on the nutritional composition of eggs is limited. Therefore, this study compared nutritional composition and component percentages of cage-produced shell eggs with respect to egg color, hen strain, and molt. Four strains were selected from the North Carolina Layer Performance and Management Test: Hy-Line Brown (HB) and Bovans Brown (BB), and Hy-Line W-36 (HW) and Bovans White (BovW) were selected. Two groups from each strain were selected and 2 groups of molted HW and BovW were selected and compared with their nonmolted counterparts to examine the molt's impact. Two sets of eggs from each replicate were collected simultaneously at 101 wk of age. One sample of eggs was broken into a 12-egg pool stomached for 3 min (n = 12 samples), then divided into six 50-mL tubes, sealed, and frozen to be sent for cholesterol, n-3 fatty acids, saturated fat, monounsaturated fats, polyunsaturated fats, β-carotene, vitamin A, and vitamin E analyses. The other set of 12 eggs was then assessed for component percentages. The HW eggs had a greater (P hens had a greater (P hens reduced (P laying hens. PMID:24235237

  6. 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

    Science.gov (United States)

    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

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

    OpenAIRE

    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 m...

  8. 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.

    Science.gov (United States)

    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. PMID:21913675

  9. Anterograde transneuronal viral tract tracing reveals central sensory circuits from brown fat and sensory denervation alters its thermogenic responses

    OpenAIRE

    Vaughan, Cheryl H.; Bartness, Timothy J.

    2012-01-01

    Brown adipose tissue (BAT) thermogenic activity and growth are controlled by its sympathetic nervous system (SNS) innervation, but nerve fibers containing sensory-associated neuropeptides [substance P, calcitonin gene-related peptide (CGRP)] also suggest sensory innervation. The central nervous system (CNS) projections of BAT afferents are unknown. Therefore, we used the H129 strain of the herpes simplex virus-1 (HSV-1), an anterograde transneuronal viral tract tracer used to delineate sensor...

  10. Patterns of brown fat uptake of 18F-fluorodeoxyglucose in positron emission tomography/computed tomography scan

    OpenAIRE

    Chakraborty, Dhritiman; Bhattacharya, Anish; Mittal, Bhagwant Rai

    2015-01-01

    Fluorodeoxyglucose (FDG) positron emission tomography (PET) has become the common imaging modality in oncological practice. FDG uptake is seen in brown adipose tissue in a significant number of patients. Recognizing the uptake patterns is important for optimal FDG PET interpretation. The introduction of PET/computed tomography (PET/CT) revolutionized PET imaging, bringing much-needed anatomical information. Careful review and correlation of FDG PET images with anatomical imaging should be per...

  11. Lithium and methylphenidate: opposite effects on perirenal brown fat Lítio e metilfenidato: efeitos opostos sobre a gordura perirrenal

    OpenAIRE

    José Menna Oliveira; Leonardo Machado Crema; Luísa Amália Diehl; Letícia Ferreira Pettenuzzo; Liane Tavares Bertinette; Carla Dalmaz; Elizabete Rocha da Rocha

    2010-01-01

    OBJECTIVE: To evaluate the effects of the administration of lithium to adult rats on brown (perirenal) and white (inguinal) adipose tissues and to assess whether methylphenidate modulates lithium effects. METHODS: Twenty-five adult male Wistar rats were fed with either regular or lithium-containing chow for 30 days. Between days 15 to 30 of treatment, animals received daily intraperitoneal administrations of either methylphenidate or saline. RESULTS: Lithium significantly reduced perirenal fa...

  12. Patterns of brown fat uptake of 18F-fluorodeoxyglucose in positron emission tomography/computed tomography scan

    International Nuclear Information System (INIS)

    Fluorodeoxyglucose (FDG) positron emission tomography (PET) has become the common imaging modality in oncological practice. FDG uptake is seen in brown adipose tissue in a significant number of patients. Recognizing the uptake patterns is important for optimal FDG PET interpretation. The introduction of PET/computed tomography (PET/CT) revolutionized PET imaging, bringing much-needed anatomical information. Careful review and correlation of FDG PET images with anatomical imaging should be performed to characterize accurately any lesion having high FDG uptake

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

    Directory of Open Access Journals (Sweden)

    Michael Karbiener

    2014-09-01

    Full Text Available 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.

  14. Ursolic Acid Increases Skeletal Muscle and Brown Fat and Decreases Diet-Induced Obesity, Glucose Intolerance and Fatty Liver Disease

    OpenAIRE

    Kunkel, Steven D.; Elmore, Christopher J.; Bongers, Kale S.; Ebert, Scott M.; Fox, Daniel K.; Dyle, Michael C.; Bullard, Steven A.; Adams, Christopher M.

    2012-01-01

    Skeletal muscle Akt activity stimulates muscle growth and imparts resistance to obesity, glucose intolerance and fatty liver disease. We recently found that ursolic acid increases skeletal muscle Akt activity and stimulates muscle growth in non-obese mice. Here, we tested the hypothesis that ursolic acid might increase skeletal muscle Akt activity in a mouse model of diet-induced obesity. We studied mice that consumed a high fat diet lacking or containing ursolic acid. In skeletal muscle, urs...

  15. Hypothesis: Cryptochromes and brown fat are essential for adaptation and affect mood and mood-related behaviors.

    Directory of Open Access Journals (Sweden)

    Timo ePartonen

    2012-11-01

    Full Text Available Solar radiation and ambient temperature have acted as selective physical forces among populations and thereby guided species distributions in the globe. Circadian clocks are universal and evolve when subjected to selection, and their properties contribute to variations in fitness within specific environments. Concerning humans, as compared to the remaining, the evening owls have a greater deviation from the 24-hour cycle, are under a greater pressure to circadian desynchrony and more prone to a cluster of health hazards with the increased mortality. Because of their position in the hierarchy and repressive actions, cryptochromes are the key components of the feedback loops on which circadian clocks are built. Based on the evidence a new hypothesis is formulated in which brown adipocytes with their cryptochromes are responsive to a broad range of physical stimuli from the habitat and through their activity ensure adaptation of the individual. The over-activated brown adipose tissue with deficient cryptochromes might induce disrupted thermoregulation and circadian desynchrony, and thereby contribute to lowered mood and pronounced depressive behaviors.

  16. Transcriptional Activity of PGC-1α and NT-PGC-1α Is Differentially Regulated by Twist-1 in Brown Fat Metabolism

    Directory of Open Access Journals (Sweden)

    Hee-Jin Jun

    2012-01-01

    Full Text Available Brown fat expresses two PGC-1α isoforms (PGC-1α and NT-PGC-1α and both play a central role in the regulation of cellular energy metabolism and adaptive thermogenesis by interacting with a wide range of transcription factors including PPARγ, PPARα, ERRα, and NRF1. PGC-1α consists of 797 amino acids, whereas alternative splicing of the PGC-1α gene produces a shorter protein called NT-PGC-1α (aa 1–270. We report in this paper that transcriptional activity of PGC-1α and NT-PGC-1α is differently affected by the transcriptional regulator, Twist-1. Twist-1 suppresses PGC-1α but not NT-PGC-1α. The inhibition of PGC-1α activity by Twist-1 is mediated by direct interaction through the C-terminal region of PGC-1α (aa 353–797. Thus, the absence of the corresponding C-terminal domain in NT-PGC-1α allows NT-PGC-1α to be free from Twist-1-mediated inhibition. Overexpression of Twist-1 in brown adipocytes suppresses transcription of a subset of PGC-1α-target genes involved in mitochondrial fatty acid oxidation and uncoupling (CPT1β, UCP1, and ERRα. In contrast, NT-PGC-1α-mediated induction of these genes is unaffected by Twist-1. These findings show that differences in inhibitory protein-protein interactions of PGC-1α and NT-PGC-1α with Twist-1 lead to differential regulation of their function by Twist-1.

  17. Lipid profile in eggs of Araucana hens compared with Lohmann Selected Leghorn and ISA Brown hens given diets with different fat sources.

    Science.gov (United States)

    Millet, S; De Ceulaer, K; Van Paemel, M; Raes, K; De Smet, S; Janssens, G P J

    2006-06-01

    1. In a cross-over trial, the egg cholesterol and fatty acid composition of Araucana hens was compared with those of two commercial breeds (Lohmann Selected Leghorn and ISA Brown) under two feeding regimes, either high (Hn-3) or low (Ln-3) in long-chain n-3 fatty acids. 2. The Hn-3 diet was formed by isocaloric substitution of animal fat in the control diet (Ln-3) by a dry product containing stabilised fish oil with standardised concentrations of eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA). 3. Both breed and diet had influences on egg composition, without interactions. 4. The Araucana breed showed lower feed intake and lower egg weights than the other two breeds. The yolk weight was similar, leading to a much higher yolk:albumen ratio in the Araucana eggs. 5. In comparison to commercial breeds, Araucanas produced eggs with higher cholesterol content per g of yolk, which was even more pronounced when expressed per g of egg, due to the high yolk content of the eggs. The cholesterol content of an egg remained unchanged by the diet, irrespective of the dietary fat source. 6. Changing to the Hn-3 diet led to greater concentrations of polyunsaturated fatty acids (PUFA) and lower concentrations of monounsaturated fatty acids (MUFA) contents in the yolk, without a change in the ratio of saturated (SFA) to unsaturated fatty acids (UFA). 7. Within the PUFA, the n-3 fatty acids increased at the expense of the n-6 fatty acids, indicating a competition between n-3 and n-6 fatty acids for incorporation in the yolk. PMID:16787853

  18. Thyroxine kinetics during ontogenesis studies by radioactive thyroxine turnover technique

    International Nuclear Information System (INIS)

    The radioactive thyroxine turnover rate was studied postnatally in 9, 18, and 35 day old rats in various intervals during 24 hours after intrajugular injection. The results support previous conclusions on the maturation of thyroidal regulatory mechanisms in this period of development. In another group of animals, the distribution of radiothyroxine was studied 4 hours after intrajugular injection on days 8, 12, 16, 20, 24, and 30 of postnatal development, and compared with the distribution of radioiodide. The results suggest that differences between age groups are not due to differences in vascularity of the organs studied, and provide indirect evidence that the differences reflect changes in the size of thyroxine binding sites. The results further indicate that in the rat, particularly during the period of weaning (the 3rd and 4th postnatal week) the T4 concentration in serum (and possibly the availability for different tissues) may be affected not only by the development of a specific neuroendocrine regulatory mechanism but also by concurrently occurring maturational changes in gastrointestinal and other functions. (author). 4 figs., 2 tabs., 18 refs

  19. Unilateral brown fat on [{sup 18}F]-F.D.G. PET/CT in the follow-up of a pleural mesothelioma; Detection unilaterale de graisse brune en [{sup 18}F]-FDG TEP/TDM dans le suivi d'un mesotheliome pleural

    Energy Technology Data Exchange (ETDEWEB)

    Waele, A. de; Deroose, C.M. [Katholieke Universiteit Leuven, Hopitaux Universitaires de Leuven, UZ Leuven, Dept. de Medecine Nucleaire, Leuven (Belgium); Nafteux, P. [Katholieke Universiteit Leuven, Hopitaux Universitaires de Leuven, Dept. de Chirurgie Thoracique, Leuven (Belgium); Nackaerts, K. [Katholieke Universiteit Leuven, Hopitaux Universitaires de Leuven, Dept. de Pneumologie, Leuven (Belgium)

    2009-10-15

    The fixation of the fluorodeoxyglucose (F.D.G.) in the brown fat is generally characterized by a strongly symmetric setting in some areas of predilection.Is reported here the case of a patient that after having undergone a multi modal treatment for a pleural mesothelioma presents a unilateral F.D.G. fixation in the brown fat, this fixation can be inhibited by the administering of a beta adrenergic blocking agent. (N.C.)

  20. Frequent extreme cold exposure and brown fat and cold-induced thermogenesis: a study in a monozygotic twin.

    Directory of Open Access Journals (Sweden)

    Maarten J Vosselman

    Full Text Available INTRODUCTION: Mild cold acclimation is known to increase brown adipose tissue (BAT activity and cold-induced thermogenesis (CIT in humans. We here tested the effect of a lifestyle with frequent exposure to extreme cold on BAT and CIT in a Dutch man known as 'the Iceman', who has multiple world records in withstanding extreme cold challenges. Furthermore, his monozygotic twin brother who has a 'normal' sedentary lifestyle without extreme cold exposures was measured. METHODS: The Iceman (subject A and his brother (subject B were studied during mild cold (13°C and thermoneutral conditions (31°C. Measurements included BAT activity and respiratory muscle activity by [18F]FDG-PET/CT imaging and energy expenditure through indirect calorimetry. In addition, body temperatures, cardiovascular parameters, skin perfusion, and thermal sensation and comfort were measured. Finally, we determined polymorphisms for uncoupling protein-1 and β3-adrenergic receptor. RESULTS: Subjects had comparable BAT activity (A: 1144 SUVtotal and B: 1325 SUVtotal, within the range previously observed in young adult men. They were genotyped with the polymorphism for uncoupling protein-1 (G/G. CIT was relatively high (A: 40.1% and B: 41.9%, but unlike during our previous cold exposure tests in young adult men, here both subjects practiced a g-Tummo like breathing technique, which involves vigorous respiratory muscle activity. This was confirmed by high [18F]FDG-uptake in respiratory muscle. CONCLUSION: No significant differences were found between the two subjects, indicating that a lifestyle with frequent exposures to extreme cold does not seem to affect BAT activity and CIT. In both subjects, BAT was not higher compared to earlier observations, whereas CIT was very high, suggesting that g-Tummo like breathing during cold exposure may cause additional heat production by vigorous isometric respiratory muscle contraction. The results must be interpreted with caution given the

  1. 吡格列酮对小鼠皮下、内脏脂肪棕色化的差异作用%The different roles of Pioglitazone in fat browning

    Institute of Scientific and Technical Information of China (English)

    李玉洁; 刘娟; 毕建华; 丁国宪

    2013-01-01

    目的:探讨吡格列酮对小鼠皮下、内脏脂肪棕色化不同作用及其机制.方法:取C57BL/5J小鼠皮下及内脏前脂肪细胞原代培养,诱导分化同时加吡格列酮刺激直至分化成熟后,RT-PCR检测棕色脂肪相关功能基因的mRNA表达水平.结果:在皮下脂肪中吡格列酮组较对照组棕色脂肪功能基因均明显表达上调(P< 0.05),而内脏脂肪对照组和吡格列酮组差异无统计学意义(P>0.05).结论:吡格列酮可促进小鼠皮下脂肪棕色化改变,但对内脏脂肪无作用.%Objective:To explore the role of Pioglitazone in the browning of both subcutaneous and visceral adipose tissue.Methods:Primary subcutaneous and visceral adipocytes were isolated from C57BL/5J mice and induced for differentiation.The primary cells were stimulated with 2.5 μmol/L Pioglitazone or vehicle throughout the whole induction period.Then the expression of either white fat or brown fat relative genes were observed by RT-PCR.Results:Pioglitazone could cause a significant increase of brown fat marker genes in the subcutaneous adipose tissue instead of the visceral adipose.Conclusion:Pioglitazone can promote a "white to brown" change in the subcutaneous adipose tissue instead of the visceral adipose.

  2. Diagnostic Value of Serum Total Thyroxine, Resin Uptake and Free Thyroxine Index

    International Nuclear Information System (INIS)

    The diagnostic accuracy of two methods for the estimation of serum total thyroxine has been studied in two series of normal subjects and patients with thyroid disease. Direct comparison has also been obtained by measurement of the thyroxine level by both techniques in 91 individuals. The commercial ''kit'', TETRA- SORB, has proved to be as accurate as the Nakajima method and with advantages in simplicity. Moreover, the similarity of the technique to the TRIOSORB method for triiodothyroxine resin uptake is particularly useful when a large routine load demands both tests frequently. Thyroxine estimation was found to be more accurate than the triiodothyroxine resin uptake in correctly discriminating between euthyroid, hypothyroid and thryotoxic patients provided that there is no abnormality in thyroxine-binding proteins. When such abnormalities are likely to be present, as for example in individuals on oral contraceptive therapy, or when the results of the primary tests are at marked variance with the clinical diagnosis, an expression relating the two tests is required. A ''Free-Thyroxine Index'', obtained from the product of the thyroxine value and resin uptake is more diagnostically accurate than either test alone, but a ''Free-Thyroxine Factor'', derived from a formula incorporating both values, is superior to the ''Index''. Fallacies in the accuracy must, however, be recognized. In particular, it has been found that the total thyroxine and resin uptake may vary unpredictably in patients with chronic renal failure. In the majority of these patients, the thyroxine level is below normal. Frequently the associated change in resin uptake results in a normal ''Index'' or ''Factor'' but in a significant proportion of these euthyroid patients both these parameters are abnormal. These alterations have not yet been explained by studies of thyroxine-binding proteins nor associated biochemical abnormalities. (author)

  3. IGFBP-2 is a negative predictor of cold-induced brown fat and bone mineral density in young non-obese women

    OpenAIRE

    Bredella, Miriam A.; Fazeli, Pouneh K.; Lecka-Czernik, Beata; Rosen, Clifford J; Klibanski, Anne

    2013-01-01

    Recent studies have shown a positive correlation between brown adipose tissue (BAT) and bone mineral density (BMD). However, mechanisms underlying this relationship are unknown. Insulin-like growth factor 1 (IGF-1) is an important regulator of stem cell differentiation promoting bone formation. IGF binding protein 2 (IGFBP-2) binds IGF-1 in the circulation and has been reported to inhibit bone formation in humans. IGF-1 is also a crucial regulator of brown adipocyte differentiation. We hypoth...

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

    Science.gov (United States)

    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.

  5. Rapid determination of thyroxine binding proteins of human serum

    Directory of Open Access Journals (Sweden)

    Arima,Terukatsu

    1976-02-01

    Full Text Available A simple method is described for determing thyroxine binding proteins in human serum by electrophoresis at pH 8.6, using cellulose acetate membrane as the supporting medium. The procedure had high reliability in sera of normal subjects, pregnant women and patients with decreased thyroxine binding capacity of thyroxine binding globulin.

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

    Data.gov (United States)

    U.S. Environmental Protection Agency — pulmonary parameters, BALF biomarkers, body composition, motor activity data collected from rats exposed to ozone after high fructose or high fat diets. This...

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

    Science.gov (United States)

    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 ...

  8. Effects of opioid antagonists naloxone and naltrexone on neuropeptide Y-induced feeding and brown fat thermogenesis in the rat. Neural site of action.

    OpenAIRE

    Kotz, C.M.; Grace, M.K.; Briggs, J.; Levine, A S; Billington, C.J.

    1995-01-01

    Neuropeptide Y administered intracerebroventricularly and into the paraventricular nucleus of the hypothalamus stimulates feeding and decreases brown adipose tissue thermogenesis. Although specific neuropeptide Y antagonists are not yet available, previous studies had shown that the opioid antagonist naloxone blocked neuropeptide Y-induced feeding when both drugs were injected intracerebroventricularly. We wanted to find out if naloxone injected into specific brain sites would block neuropept...

  9. Rictor/mTORC2 Loss in the Myf5 Lineage Reprograms Brown Fat Metabolism and Protects Mice against Obesity and Metabolic Disease

    Directory of Open Access Journals (Sweden)

    Chien-Min Hung

    2014-07-01

    Full Text Available 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.

  10. 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

    Directory of Open Access Journals (Sweden)

    Hadiza Altine Adamu

    2016-02-01

    Full Text Available 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.

  11. Vanishing large ovarian cyst with thyroxine therapy

    OpenAIRE

    Dharmshaktu, Pramila; Kutiyal, Aditya; Dhanwal, Dinesh

    2013-01-01

    Summary A 21-year-old female patient recently diagnosed with severe hypothyroidism was found to have a large ovarian cyst. In view of the large ovarian cyst, she was advised to undergo elective laparotomy in the gynaecology department. She was further evaluated in our medical out-patient department (OPD), and elective surgery was withheld. She was started on thyroxine replacement therapy, and within a period of 4 months, the size of the cyst regressed significantly, thereby improving the cond...

  12. Thyroxine Level of Children with Cerebral Palsy

    Institute of Scientific and Technical Information of China (English)

    Zhang Jie

    2000-01-01

    Objective:To investigate the thyroxine level of Children with cerebral palsy so as to understand thd changes of their nevous endocrine. Methods:Radioimmunoassay was applied to 57 Children with cerebral palsy and 108 normal children.The serum level of tridothyronine(T3), thyroxine(T4)free tridothyronine(FT3),free thyroxin(FT4),and thyroid stimulating hormone(TSH) were measured for those children in the moming and and in condition without any food Rsults: (1)Chiidren with cerebral palsy all showed low T3 values.The difference of T3 value between CP children and norrmal children was significant (P<0.001). (2)Results from groups with difference ages:the CP toddler′s age group also showed low T4 and FT4 values The difference of T4 and FT4 values between the toddler′s age CP childrengroup and the toddler′s age normal children group tegted was significant (CP<0.01 for T4, P <0. 05 for FT4): Conclusion:The tlyroxine level of children with cerebral palsy showed lower values compared to normal children, especisly, the low T3 values were significant.

  13. IGFBP-2 is a negative predictor of cold-induced brown fat and bone mineral density in young non-obese women.

    Science.gov (United States)

    Bredella, Miriam A; Fazeli, Pouneh K; Lecka-Czernik, Beata; Rosen, Clifford J; Klibanski, Anne

    2013-04-01

    Recent studies have shown a positive correlation between brown adipose tissue (BAT) and bone mineral density (BMD). However, mechanisms underlying this relationship are unknown. Insulin-like growth factor 1 (IGF-1) is an important regulator of stem cell differentiation promoting bone formation. IGF binding protein 2 (IGFBP-2) binds IGF-1 in the circulation and has been reported to inhibit bone formation in humans. IGF-1 is also a crucial regulator of brown adipocyte differentiation. We hypothesized that IGFBP-2 is a negative and IGF-1 a positive regulator of BAT-mediated osteoblastogenesis. We therefore investigated a cohort of 15 women (mean age 27.7±5.7years): 5 with anorexia nervosa (AN) in whom IGF-1 levels were low due to starvation, 5 recovered AN (AN-R), and 5 women of normal weight. All subjects underwent assessment of cold-activated BAT by PET/CT, BMD of the spine, hip, femoral neck, and total body by DXA, thigh muscle area by MRI, IGF-1 and IGFBP-2. There was a positive correlation between BAT and BMD and an inverse association between IGFBP-2 and both BAT and BMD. There was no association between IGF-1 and BAT. We show for the first time that IGFBP-2 is a negative predictor of cold-induced BAT and BMD in young non-obese women, suggesting that IGFBP-2 may serve as a regulator of BAT-mediated osteoblastogenesis. PMID:23291564

  14. Sustained Brown Fat Stimulation and Insulin Sensitization by a Humanized Bispecific Antibody Agonist for Fibroblast Growth Factor Receptor 1/βKlotho Complex

    Directory of Open Access Journals (Sweden)

    Ganesh Kolumam

    2015-07-01

    Full Text Available Dissipating excess calories as heat through therapeutic stimulation of brown adipose tissues (BAT has been proposed as a potential treatment for obesity-linked disorders. Here, we describe the generation of a humanized effector-less bispecific antibody that activates fibroblast growth factor receptor (FGFR 1/βKlotho complex, a common receptor for FGF21 and FGF19. Using this molecule, we show that antibody-mediated activation of FGFR1/βKlotho complex in mice induces sustained energy expenditure in BAT, browning of white adipose tissue, weight loss, and improvements in obesity-associated metabolic derangements including insulin resistance, hyperglycemia, dyslipidemia and hepatosteatosis. In mice and cynomolgus monkeys, FGFR1/βKlotho activation increased serum high-molecular-weight adiponectin, which appears to contribute over time by enhancing the amplitude of the metabolic benefits. At the same time, insulin sensitization by FGFR1/βKlotho activation occurs even before the onset of weight loss in a manner that is independent of adiponectin. Together, selective activation of FGFR1/βKlotho complex with a long acting therapeutic antibody represents an attractive approach for the treatment of type 2 diabetes and other obesity-linked disorders through enhanced energy expenditure, insulin sensitization and induction of high-molecular-weight adiponectin.

  15. Sustained Brown Fat Stimulation and Insulin Sensitization by a Humanized Bispecific Antibody Agonist for Fibroblast Growth Factor Receptor 1/βKlotho Complex

    Science.gov (United States)

    Kolumam, Ganesh; Chen, Mark Z.; Tong, Raymond; Zavala-Solorio, Jose; Kates, Lance; van Bruggen, Nicholas; Ross, Jed; Wyatt, Shelby K.; Gandham, Vineela D.; Carano, Richard A.D.; Dunshee, Diana Ronai; Wu, Ai-Luen; Haley, Benjamin; Anderson, Keith; Warming, Søren; Rairdan, Xin Y.; Lewin-Koh, Nicholas; Zhang, Yingnan; Gutierrez, Johnny; Baruch, Amos; Gelzleichter, Thomas R.; Stevens, Dale; Rajan, Sharmila; Bainbridge, Travis W.; Vernes, Jean-Michel; Meng, Y. Gloria; Ziai, James; Soriano, Robert H.; Brauer, Matthew J.; Chen, Yongmei; Stawicki, Scott; Kim, Hok Seon; Comps-Agrar, Laëtitia; Luis, Elizabeth; Spiess, Christoph; Wu, Yan; Ernst, James A.; McGuinness, Owen P.; Peterson, Andrew S.; Sonoda, Junichiro

    2015-01-01

    Dissipating excess calories as heat through therapeutic stimulation of brown adipose tissues (BAT) has been proposed as a potential treatment for obesity-linked disorders. Here, we describe the generation of a humanized effector-less bispecific antibody that activates fibroblast growth factor receptor (FGFR) 1/βKlotho complex, a common receptor for FGF21 and FGF19. Using this molecule, we show that antibody-mediated activation of FGFR1/βKlotho complex in mice induces sustained energy expenditure in BAT, browning of white adipose tissue, weight loss, and improvements in obesity-associated metabolic derangements including insulin resistance, hyperglycemia, dyslipidemia and hepatosteatosis. In mice and cynomolgus monkeys, FGFR1/βKlotho activation increased serum high-molecular-weight adiponectin, which appears to contribute over time by enhancing the amplitude of the metabolic benefits. At the same time, insulin sensitization by FGFR1/βKlotho activation occurs even before the onset of weight loss in a manner that is independent of adiponectin. Together, selective activation of FGFR1/βKlotho complex with a long acting therapeutic antibody represents an attractive approach for the treatment of type 2 diabetes and other obesity-linked disorders through enhanced energy expenditure, insulin sensitization and induction of high-molecular-weight adiponectin. PMID:26288846

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

    Science.gov (United States)

    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

  17. Acute mania after thyroxin supplementation in hypothyroid state

    OpenAIRE

    Rohit Verma; Ankur Sachdeva; Yogendra Singh; Balhara, Yatan P.S.

    2013-01-01

    The current literature variedly ascribes depressive and manic symptoms to hypo- and hyperthyroid state, respectively, reporting mania in hypothyroidism as an unusual entity. More unusual is precipitation of manic state in hypothyroid subjects after thyroxine supplementation for which studies report otherwise treating manic symptoms in hypothyroid state with thyroxine. We report a case of a patient whose acute mania appears to have been precipitated by thyroxine supplementation in hypothyroidi...

  18. Acute mania after thyroxin supplementation in hypothyroid state

    Directory of Open Access Journals (Sweden)

    Rohit Verma

    2013-01-01

    Full Text Available The current literature variedly ascribes depressive and manic symptoms to hypo- and hyperthyroid state, respectively, reporting mania in hypothyroidism as an unusual entity. More unusual is precipitation of manic state in hypothyroid subjects after thyroxine supplementation for which studies report otherwise treating manic symptoms in hypothyroid state with thyroxine. We report a case of a patient whose acute mania appears to have been precipitated by thyroxine supplementation in hypothyroidism state. This case underscores the importance of thyroid screening in patients with mood and psychotic disorders, as well as the potency of thyroxine in producing manic symptoms.

  19. Beige Adipocytes are a Distinct Type of Thermogenic Fat Cell in Mouse and Human

    OpenAIRE

    Wu, Jun; Boström, Pontus; Sparks, Lauren M; Ye, Li; Choi, Jang Hyun; Giang, An-Hoa; Khandekar, Melin; Nuutila, Pirjo; Schaart, Gert; Huang, Kexin; Tu, Hua; van Marken Lichtenbelt, Wouter D; Hoeks, Joris; Enerbäck, Sven; Schrauwen, Patrick

    2012-01-01

    Brown fat defends against hypothermia and obesity through thermogenesis mediated by mitochondrial UCP1. Recent data suggest that there are two distinct types of brown fat: classical brown fat derived from a myf-5 cellular lineage and UCP1-positive cells that emerge in white fat from a non-myf-5 lineage. Here we report the cloning of “beige” cells from murine white fat depots. Beige cells resemble white fat cells in having extremely low basal expression of UCP1, but like classical brown fat, t...

  20. Determination of thyroxine concentration in serum by competitive protein binding assay

    International Nuclear Information System (INIS)

    This paper summarized the kits in commercial level used for the determination of thyroxine concentration in serum by competitive protein binding assay, and described the recent tendency. Using the kits in commercial level such as Tetrasorb, Res-O-Mat T4, Thyopac-4 and Tetralute, extraction of thyroxine, culture of 125I-thyroxine of thyroxine-binding-globulin, separation of free 125I-thyroxine from thyroxine-binding-globulin binding 125I-thyroxine, and calculation of thyroxine concentration were explained, and strong or weak points of these kits were examined. Although normal value showed a little difference in the four kits, they reflected well the thyroid function and would be able to be clinically applied. In addition, Res-O-Mat Effective Thyroxine Ratio Test was recently improved to measure free thyroxine index and thyroxine concentration at the same time, and the effectiveness of the test was also explained. (Kanao, N.)

  1. Diagnostic Evaluation of Effective Thyroxine Ratio

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Myung Chul; Choi, Sang Jae; Ro, Heung Kyu; Lee, Hong Kyu; Koh, Chang Soon; Lee, Mun Ho [Seoul National University College of Medicine, Seoul (Korea, Republic of)

    1975-09-15

    The purpose of the present study is to evaluate the diagnostic value of the ETR test as compared to other thyroid function tests in normal persons, patients with thyroid disorders and patients with alterations of thyroxine-binding proteins. The ETR values were obtained from 35 cases as normal control, 63 hyperthyroid patients, 56 euthyroid patients, 23 hypothyroid patients, 10 pregnant women, 5 women taking oral contraceptive medication, 8 liver cirrhosis patients and 4 nephrotic syndrome patients. The results obtained were as follows. 1) The mean value of ETR obtained from the normal controls was 0.99+-0.06. 2) The mean ETR values of various thyroid states were 1.25+-0.16 in hyperthyroidism, 0.99+-0.08 in euthyroidism and 0.82+-0.05 in hypothyroidism and significant difference was found between these groups. 3) Seven out of 63 hyperthyroid patients (11.1%) and 2 out of 23 hypothyroid patients (8.7%) had ETR values within normal range and among the 56 euthyroid patients 6 (10.7%) had ETR values outside normal range, so the diagnostic compatibility of ETR was 89.4% in thyroid diseases. 4) Even though the ETR value was well correlated with {sup 131}I-thyroid uptake rate, serum T{sub 3} resin uptake rate and serum T{sub 4}, a high positive correlation was found (r=0.79) between ETR and T{sub 7}. 5) The mean ETR values from patients with alteration in TBG binding capacity were 0.99+-0.05 in pregnant women, 0.98+-0.04 in women with oral contraceptive medication, 1.04+-0.09 in liver cirrhosis patients and 0.94+-0.02 in nephrotic syndrome patients and most of them (85.2%) had ETR values within normal range. Our results, therefore, suggests that the ETR estimation does offer the simplest and most reliable single procedure for the screening and diagnosis of various thyroid diseases as a indirect indicator of serum-free thyroxine concentration without essential influence of changes in the thyroxine-binding proteins in serum.

  2. Diagnostic Evaluation of Effective Thyroxine Ratio

    International Nuclear Information System (INIS)

    The purpose of the present study is to evaluate the diagnostic value of the ETR test as compared to other thyroid function tests in normal persons, patients with thyroid disorders and patients with alterations of thyroxine-binding proteins. The ETR values were obtained from 35 cases as normal control, 63 hyperthyroid patients, 56 euthyroid patients, 23 hypothyroid patients, 10 pregnant women, 5 women taking oral contraceptive medication, 8 liver cirrhosis patients and 4 nephrotic syndrome patients. The results obtained were as follows. 1) The mean value of ETR obtained from the normal controls was 0.99±0.06. 2) The mean ETR values of various thyroid states were 1.25±0.16 in hyperthyroidism, 0.99±0.08 in euthyroidism and 0.82±0.05 in hypothyroidism and significant difference was found between these groups. 3) Seven out of 63 hyperthyroid patients (11.1%) and 2 out of 23 hypothyroid patients (8.7%) had ETR values within normal range and among the 56 euthyroid patients 6 (10.7%) had ETR values outside normal range, so the diagnostic compatibility of ETR was 89.4% in thyroid diseases. 4) Even though the ETR value was well correlated with 131I-thyroid uptake rate, serum T3 resin uptake rate and serum T4, a high positive correlation was found (r=0.79) between ETR and T7. 5) The mean ETR values from patients with alteration in TBG binding capacity were 0.99±0.05 in pregnant women, 0.98±0.04 in women with oral contraceptive medication, 1.04±0.09 in liver cirrhosis patients and 0.94±0.02 in nephrotic syndrome patients and most of them (85.2%) had ETR values within normal range. Our results, therefore, suggests that the ETR estimation does offer the simplest and most reliable single procedure for the screening and diagnosis of various thyroid diseases as a indirect indicator of serum-free thyroxine concentration without essential influence of changes in the thyroxine-binding proteins in serum.

  3. Distribution of /sup 125/I-thyroxine in different organs and tissues of dietically obese rats

    Energy Technology Data Exchange (ETDEWEB)

    Hartmann, K.; Voss, C.; Huebner, G. (Ernst-Moritz-Arndt-Universitaet, Greifswald (German Democratic Republic)); Weber, A. (Ernst-Moritz-Arndt-Universitaet, Greifswald (German Democratic Republic). Radiologische Klinik)

    1985-04-01

    The distribution of /sup 125/I-thyroxine (% dose/g tissue; tissue/plasma radioactivity ratio) was investigated in different tissues of 28-week-old obese Wistar rats. Obesity was induced by high-fat diet (HFD) and confirmed by carcass analysis; in heavy obese animals the relative and absolute fat content is increased twofold and threefold, respectively, compared to control rats fed on a low-fat diet (LFD). Heavy HFD rats exhibit diminished /sup 125/I-T/sub 4/ distribution in the 'slow pool' (fat tissue, muscle) and unchanged values in the 'fast pool' (liver, kidneys) in comparison with LFD rats with low body weight. The differences in distribution presented here are not caused by the diet per se, but they are the consequence of the obesity of the animal, because no differences in the /sup 125/I-T/sub 4/ distribution were found in the /sup 125/I-T/sub 4/ between HFD and LFD rats with relatively equal body weight and body composition. The reduced T/sub 4/ distribution in the fat tissue of obese rats is discussed in connection with possibly decreased lipolysis in this tissue and possible causal participation in the beginning of obesity.

  4. Distribution of 125I-thyroxine in different organs and tissues of dietically obese rats

    International Nuclear Information System (INIS)

    The distribution of 125I-thyroxine (% dose/g tissue; tissue/plasma radioactivity ratio) was investigated in different tissues of 28-week-old obese Wistar rats. Obesity was induced by high-fat diet (HFD) and confirmed by carcass analysis; in heavy obese animals the relative and absolute fat content is increased twofold and threefold, respectively, compared to control rats fed on a low-fat diet (LFD). Heavy HFD rats exhibit diminished 125I-T4 distribution in the 'slow pool' (fat tissue, muscle) and unchanged values in the 'fast pool' (liver, kidneys) in comparison with LFD rats with low body weight. The differences in distribution presented here are not caused by the diet per se, but they are the consequence of the obesity of the animal, because no differences in the 125I-T4 distribution were found in the 125I-T4 between HFD and LFD rats with relatively equal body weight and body composition. The reduced T4 distribution in the fat tissue of obese rats is discussed in connection with possibly decreased lipolysis in this tissue and possible causal participation in the beginning of obesity. (author)

  5. Developmental Triclosan Exposure Decreases Maternal and Offspring Thyroxine in Rats*

    Science.gov (United States)

    Epidemiological and laboratory data have demonstrated that disruption of maternal thyroid hormones during fetal developmental may result in irreversible neurological consequences in offspring. In a short-term exposure paradigm, triclosan decreased systemic thyroxine (T4) concentr...

  6. Selenium derivatives of thyroxine and tri-iodothyronine

    International Nuclear Information System (INIS)

    Novel selenium derivatives of thyroxine and tri-iodothyronine are described. They preferably contain at least one 75Se atom. The compounds are useful in dual isotope assays of thyroid function. (U.K.)

  7. Thyroxin Is Useful to Improve Sperm Motility

    Directory of Open Access Journals (Sweden)

    Mendeluk Gabriela Ruth

    2016-07-01

    Full Text Available Background The aim of this study was to evaluate the non-genomic action of thyroxin on sperm kinetic and its probable use to improve sperm recovery after applying an en- richment method like “swim-up” in comparison with the available one, pentoxifylline. Materials and Methods This is an experimental study. A total of 50 patients were re- cruited, followed by infertility consultation. Conventional sperm assays were performed according to World Health Organization criteria-2010 (WHO-2010. A Computer Aided Semen Analysis System was employed to assess kinetic parameters and concentrations. Number of the motile sperm recovered after preparation technique was calculated. Results Addition of T4 (0.002 µg/ml to semen samples increased hypermotility at 20 minutes (control: 14.18 ± 5.1% vs. 17.66 ± 8.88%, P<0.03, data expressed as mean ± SD and remained unchanged after 40 minutes. Significant differences were found in the motile sperm recovered after swim-up (control: 8.93×106 ± 9.52× 06vs. 17.20×106 ± 21.16×106, P<0.03, achieving all of the tested samples a desirable threshold value for artificial insemination outcome, while adding pentoxifylline increased the number of recovered sperm after swim-up in 60% of the studied cases. No synergism between two treatments could be determined. Conclusion We propose a new physiological tool to artificially improve insemination. The discussion opens windows to investigate unknown pathways involved in sperm ca- pacitation and gives innovative arguments to better understand infertility mechanisms.

  8. Thyroxine and triiodothyronine kinetics in aging subjects

    International Nuclear Information System (INIS)

    Age modifications on serum levels of thyrotropin hormone (TSH) thyroxine (T4) and Triiodothyronine (T3), as well the kinetics of T4 and T3 were studied. T4 serum values were found to be in the normal range. T3 rates showed a significant decrease as TSH showed a slight increase, which was only significantin patients over 70 year-old. Metabolic T4 turnover allowed to observe a slower T4 disappearance rate with dialy degradation values of 35,4 μg/day/m2+-14,1 (S.D.)as compared with those of the control subjects (49,0+-14,6): Distribution space was in the normal range. On the contrary, for T3 a sharp decrease in distribution space (31,1% body weight+-3,5; controls 58,8%+-7,6), a slight lengthening in disappearance rate and a marked shortening of the clearance (17,32 l/d+-6,20; controls 33,72+-8.55), of T3 extrathyroid pool (14,5 μg+-1,8; controls 45,7+-4.7) and of the daily degradation rate (4,3 μg/d/m2+-1,7; controls: 15,3+-2,6) were observed. These results conveys to considere a diminished thyroid hormones production and of an also diminished peripheric conversion of T4 to T3. It should be delucidated if there is a real inadequate thyroid hormones suply to the tissues or if there is only an adaptation, to lower demands due to a diminished functional mass

  9. Biosensor discovery of thyroxine transport disrupting chemicals

    International Nuclear Information System (INIS)

    Ubiquitous chemicals may interfere with the thyroid system that is essential in the development and physiology of vertebrates. We applied a surface plasmon resonance (SPR) biosensor-based screening method for the fast screening of chemicals with thyroxine (T4) transport disrupting activity. Two inhibition assays using the main thyroid hormone transport proteins, T4 binding globulin (TBG) and transthyretin (TTR), in combination with a T4-coated biosensor chip were optimized and automated for screening chemical libraries. The transport protein-based biosensor assays were rapid, high throughput and bioeffect-related. A library of 62 chemicals including the natural hormones, polychlorinated biphenyls (PCBs), polybrominated diphenylethers (PBDEs) and metabolites, halogenated bisphenol A (BPA), halogenated phenols, pharmaceuticals, pesticides and other potential environmentally relevant chemicals was tested with the two assays. We discovered ten new active compounds with moderate to high affinity for TBG with the TBG assay. Strikingly, the most potent binding was observed with hydroxylated metabolites of the brominated diphenyl ethers (BDEs) BDE 47, BDE 49 and BDE 99, that are commonly found in human plasma. The TTR assay confirmed the activity of previously identified hydroxylated metabolites of PCBs and PBDEs, halogenated BPA and genistein. These results show that the hydroxylated metabolites of the ubiquitous PBDEs not only target the T4 transport at the TTR level, but also, and to a great extent, at the TBG level where most of the T4 in humans is circulating. The optimized SPR biosensor-based transport protein assay is a suitable method for high throughput screening of large libraries for potential thyroid hormone disrupting compounds

  10. Lowland amphibians - recalculation of data on effects of diluted thyroxine

    Directory of Open Access Journals (Sweden)

    Peter Christian Endler

    2012-04-01

    Full Text Available Our previous paper described methodological problems and a generally acceptable pooling method for metamorphosis experiments and application of that method to the results of multicentre experiments performed over the course of two decades (1990 - 2010 on highland amphibians (Rana temporaria treated with a homeopathically prepared high dilution of thyroxine (“30x”. Differences between treatment groups thus calculated were in line with those obtained with other pooling methods: Thyroxine 30x does slow down metamorphosis in highland amphibians. This follow up paper provides a broader background on metamorphosis physiology and describes application of the pooling method to experiments with Rana temporaria from lowland biotopes both with a moderate dilution of thyroxine (“8x” and with 30x. Analogously prepared water was used for control (water 8x or 30x. Development was, again as above, monitored by documenting the number of animals that had entered the 4-legged stage. Experiments were carried out between 1990 and 2000 by different researchers independently and in blind. As it is well known, metamorphosis can be speeded up by thyroxine 10-8 mol/l; interestingly, thyroxine 8x may produce a reverse, i.e. inhibiting effect (p 0.05. However, an inhibiting effect on lowland larvae was found when animals were treated from the spawn stage on (p < 0.01.

  11. Effects of thyroxine and dexamethasone on rat submandibular glands

    International Nuclear Information System (INIS)

    Glucocorticoids and thyroxine are known to have a marked effect on the flow rate and protein composition of rat parotid saliva in hormonally intact animals. In the present study, the effects of a one-week treatment of male rats with dexamethasone and thyroxine were studied by electron microscopy and x-ray micro-analysis, and by measurement of the flow rate and determination of the chemical composition of pilocarpine-induced submandibular saliva. Thyroxine had the most extensive effects on the submandibular gland. The acinar cells were enlarged and filled with mucus; the cellular calcium concentration was significantly increased. The flow rate of the submandibular saliva was significantly reduced compared with that in saline-injected control animals. Thyroxine caused an increase in the concentrations of protein, total calcium, and potassium in the saliva. Dexamethasone had no significant effects on gland ultrastructure or on the elemental composition of the acinar cells; flow rate was not affected, but the concentrations of protein, calcium, and potassium were significantly increased. The effects of dexamethasone and thyroxine on the flow rate and protein composition of pilocarpine-induced rat submandibular saliva differ from those reported earlier for rat parotid saliva after simultaneous stimulation with pilocarpine and isoproterenol

  12. Radioactive determination of serum thyroxine. [/sup 125/I tracer technique

    Energy Technology Data Exchange (ETDEWEB)

    Shannon, C.F.; Dahlstrom, R.V.

    1976-03-30

    A method for determining serum thyroxine (T-4) in which the T-4 is first separated from the serum by adsorption onto a montmorillonite clay and then competitively bound by exogenous thyroxine binding globulin in the presence of a known amount of radioactive T-4. The competitively bound serum T-4 and radioactive T-4 is separated from the unbound serum T-4 and radioactive T-4 by passage through an ion exchange resin column. The serum T-4 concentration is determined by measuring the amount of bound radioactive T-4 and referring to a standard curve.

  13. Radioimmunological determination of total thyroxine in the serum

    International Nuclear Information System (INIS)

    A radioimmunological method to determine total thyroxine in a serum sample is described. The method is as follows: trichloracetic acid and sodium hydroxide are mixed with the sample; radioactive thyroxine is added to the mixture, which is left to reach equilibrium then placed in contact with a resin sponge consisting of a polyurethane foam with intercommunicating cells containing a strongly basic anion exchange resin; the mixture and the resin sponge are incubated, the initial radioactivity of the mixture and resin sponge combination is measured with an appropriate detection system, then the resin sponge is removed from the mixture, washed and its residual radioactivity measured

  14. Circadian variations of serum thyroxine, free thyroxine and 3,5,3'triiodothyronine concentrations in healthy dogs

    OpenAIRE

    Hoh, Woo-Pil; Oh, Tae-Ho

    2006-01-01

    This study was to determine the daily fluctuation of serum thyroxine (tT4), free thyroxine (fT4), 3,5,3'-triiodothyronine (T3) concentrations in healthy dogs. Thyroid function of these dogs was evaluated on the basis of results of TSH response test. Samples for the measurement of serum tT4, fT4, and T3 concentrations were obtained at 3-hour intervals from 8 : 00 to 20 : 00. Serum tT4, fT4, and T3 concentrations were measured by the enzyme chemiluminescent immunoassay (ECLIA). Mean T3 concentr...

  15. Peripheral Serum Thyroxine, Triiodothyronine and Reverse Triiodothyronine Kinetics in the Low Thyroxine State of Acute Nonthyroidal Illnesses: A NONCOMPARTMENTAL ANALYSIS

    OpenAIRE

    Kaptein, Elaine M.; Robinson, William J.; Grieb, Deborah A.; Nicoloff, John T.

    1982-01-01

    The low thyroxine (T4) state of acute critical nonthyroidal illnesses is characterized by marked decreases in serum total T4 and triiodothyronine (T3) with elevated reverse T3 (rT3) values. To better define the mechanisms responsible for these alterations, serum kinetic disappearance studies of labeled T4, T3, or rT3 were determined in 16 patients with the low T4 state and compared with 27 euthyroid controls and a single subject with near absence of thyroxine-binding globulin. Marked increase...

  16. Preparation of standards of triiodothyronine, thyroxine and thyrotropin

    International Nuclear Information System (INIS)

    The standards preparation requires of certain basic principles, some of which are described in this work, which was made with the purpose of establishing the most appropriate conditions for the preparation of standards of triiodothyronine, thyroxine and thyrotropin to be used in radioimmunoanalysis essays. The diverse standards show a balanced displacement, that which is observed in the graphs presented in this work. (Author)

  17. Applications of Iodine-132 in Studies of Thyroxine Turnover

    International Nuclear Information System (INIS)

    Iodine-132 has been applied in our laboratories to two different problems in thyroid physiology. Determination of radiation damage to the thyroid at relatively low doses of internal radiation: It has been found that the rate of production of protein-bound iodine (PBI) by the thyroid significantly increases 24 h after the thyroid has absorbed doses of internal radiation in the range 50-100 rad. These findings were made possible by using l131 as the source of internal radiation and I132 as an indicator of the rate of production of PBI. Next, I132 was used as a source of internal radiation as well as a tracer for PB I production, because it was possible to determine the effects oí radiation without interference of the radiological dose. These experiments, which have been carried out on rats, are presently being extended to human patients to determine the possible radiation damage of tracer doses of I131. During this investigation, special techniques were developed to cope with the specific requirements of using I132 in thyroid studies. A quantitative determination of the rate of thyroxine deiodination in humans: In the course of an extensive investigation of factors which affect the rate of deiodination of thyroxine in mice and rats it became of interest to determine this process in humans. The change in concentration of labelled thyroxine with time reflects the composite disappearance of thyroxine, including clearance via liver and re-absorption from intestines. In any procedure chosen, the inorganic iodide liberated from the labelled thyroxine has to be assayed. Consequently the fate of iodide in the system determines the method of investigation. In humans the relative rates of deiodination and iodide clearance are about 1: 70 and thus a steady-state concentration of iodide in serum is attained. The stationary concentration of labelled iodide, originating from the degraded labelled thyroxine, is dependent on two parameters — the rate of deiodination of thyroxine

  18. Cannabidiol promotes browning in 3T3-L1 adipocytes.

    Science.gov (United States)

    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. PMID:27067870

  19. Cell biology of fat storage.

    Science.gov (United States)

    Cohen, Paul; Spiegelman, Bruce M

    2016-08-15

    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

  20. Development of a simple method for the immobilization of anti-thyroxine antibody on polystyrene tubes for use in the measurement of total thyroxine in serum

    International Nuclear Information System (INIS)

    We describe a simple method for the immobilisation of anti-thyroxine antibody on to the surface of polystyrene tubes and a simple assay format for the quantitative estimation of total thyroxine in serum. The immobilisation of anti-thyroxine antibody was achieved through passive adsorption of normal rabbit gamma globulin and anti-rabbit antibody raised in goat, as immune bridges. This procedure ensured minimum utilisation of primary and secondary antibody as neat sera without precipitation or affinity purification. The developed assay system using these antibody coated tubes covers a range of 0-240 ng/mL of thyroxine with intra and inter assay variations of less than 10 %. (author)

  1. Measurement of free thyroxine or free 3,5,3'-triiodothyronine in a liquid sample

    International Nuclear Information System (INIS)

    An immunoassay method is described for the direct measurement of free thyroxine or 3,5,3'-triiodothyronine in a liquid sample in which the thyroxine or 3,5,3'-triiodothyronine is present in both free and combined states. The sample is combined with a labelled thyroxine- or 3,5,3'-triiodothyronine-horseradish peroxidase conjugate which does not significantly interact with thyroxine-binding globulin, thyroxine-binding prealbumin and immobilised antibody which is specific for thyroxine or 3,5,3'-triiodothyronine. After incubation, the solid phase is separated from the liquid phase and the amount of labelled thyroxine- or 3,5,3'-triiodothyronine-horseradish peroxidase conjugate present in either phase is measured by determining the activity of the label. (author)

  2. Free thyroxin by radioimmunoassay: evaluation of a new direct method involving a radiolabeled thyroxin analog

    International Nuclear Information System (INIS)

    The first performance evaluation of a new direct method for free thyroxin (T4) in serum by radioimmunoassay, with use of coated tubes and a radioiodinated T4 analog (Diagnostic Products Corp.) is presented. The assay is precise and robust: within-run imprecision (CV), 3.1-6.6%; between-run imprecision, 4.0-7.9%; no demonstrable variation between technologists irrespective of experience with the method. No outliers were observed when we compared the free T4 results with serum total T4. Reference values are reported for a total of 1243 euthyroid subjects; there was no significant age effect on serum free T4 in women 26 to 72 years old. The biological variation was about +/- 35% of the mean (2 SD). Free T4 results are the same for serum and plasma. The assay performs well in hypothyroidism and hyperthyroidism, and distinguishes individuals with thyroid disease from normal individuals. Free T4 values in women taking oral contraceptives are normal. Depressed results were often observed in acute nonthyroidal illness and continuing pregnancy. These results were directly comparable with those of another commercial direct radiolabeled-T4 analog kit for free T4

  3. Simultaneous radioimmunoassay of thyrotropin and thyroxine in human serum

    International Nuclear Information System (INIS)

    The importance of early diagnosis and treatment of congenital hypothyroidism has been well established, and several screening programs have been undertaken to detect neonates with this disorder by measurement of concentrations of thyrotropin or thyroxine in the serum. However, measurement of either hormone alone may fail to identify all affected patients. Accordingly, we have established a simulatneous double-antibody, dual-isotope radioimmunoassay for both. Sensitivity, slope, analytical recovery, and precision characteristics of the simultaneous assay do not differ from those of each assay performed separately. Values for the two analyses in the single and simultaneous assays correlate well (r = 0.951 for thyroxine, 0.983 for thyrotropin). This assay system permits determination of both hormones within 72 h after specimen collection and thus should allow more rapid evaluation, diagnosis, and treatment of infants with congenital hypothyroidism

  4. Brown Adipose Tissue Growth and Development

    Directory of Open Access Journals (Sweden)

    Michael E. Symonds

    2013-01-01

    Full Text Available 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.

  5. A method of radiocompetitive assay of total thyroxine in the serum by means of enzymatic release of thyroxine from the transporting proteins

    International Nuclear Information System (INIS)

    Pepsin causes denaturation of the transporting proteins and liberates thyroxine which can be assayed by the radiocompetitive method. Change of the pH of the medium from acid to alkaline inactivates irreveribly pepsin. The enzymatic release of thyroxine is much simpler that the method of ethanol extraction and thermal denaturation of the transporting proteins applied up to now. The new technique of thyroxine release has been introduced for radiocompetitive determination of thyroxine using dextran coated charcoal for adsorption of the free hormone. A new method has been elaborated for preparation of working standards of thyroxine in a mixture of pepsin solution with hormone-free serum. The method is efficient and rapid. The normal range is from 50 to 130 nanomol/l. Over 7 000 determinations were done as yet in patients with suspected thyroid function disturbances. (author)

  6. Intermittent cold exposure induces fat deposition in mice /

    OpenAIRE

    Yoo, Hyung sun

    2013-01-01

    Brown adipose tissue (BAT) is the most essential thermogenic organ in homeotherms. In mice, brown adipocytes like cells (beige adipocytes) appear in subcutaneous fat depot after prolonged cold exposure. Fully-functioning BAT and beige adipocytes in subcutaneous fat depot drive a sharp increase in energy expenditure. In fact, cold-elicited BAT activation and beige cell recruitment in subcutaneous adipose tissue have shown anti -obesity effect, making them a promising target for obesity treatme...

  7. Effect of Brown Rice Protein and Its Hydrolysates on Lipid Metabolism in High-fat Diet on Syrian hamsters%糙米蛋白及其酶解产物对喂食高脂饲料叙利亚金仓鼠脂质代谢的影响

    Institute of Scientific and Technical Information of China (English)

    张慧娟; Wally Yokoyama; 张晖

    2012-01-01

    This study investigated the effect of brown rice protein(BRP) and BRP hydrolysates(BRPH)on lipoprotein metabolism in Syrian Golden hamsters fed high-fat diets compared to casein.The supplements of brown rice protein and its hydrolysates reduced hepatic total lipid,total cholesterol and free cholesterol content of hamster.Meanwhile,the BRP and BRPH diet increased the fecal total lipid,total cholesterol and free cholesterol content.Moreover,BRPH significantly reduced the hamster body weight compared to control.%以动物性蛋白酪蛋白为对照,研究了糙米蛋白及其酶解产物对叙利亚金仓鼠脂质代谢的影响。糙米蛋白及其酶解产物降低了仓鼠肝脏中总脂肪、总胆固醇和游离胆固醇含量,同时增加了粪便中脂肪及胆固醇的排出量。糙米蛋白酶解产物还可以显著降低仓鼠的体重。

  8. Aspectos produtivos da raça Pardo-Suíça no Brasil: Fatores de ajustamento, produção de leite e de gordura, e parâmetros genéticos Productive aspects of the brown Swiss Breed in Brazil: Adjustment factors, milk and fat yields, and genetic parameters

    Directory of Open Access Journals (Sweden)

    Francisco Palma Rennó

    2002-09-01

    Full Text Available Foi realizado um estudo sobre o desempenho produtivo da raça Pardo-Suíça com o objetivo de estimar fatores de ajustamento, avaliar fatores de ambiente e genéticos que influenciam a produção de leite, de gordura e a porcentagem de gordura, e estimar parâmetros genéticos para estas características produtivas. Foram avaliadas 11189 lactações de 5382 vacas Pardo-Suíças, de 1980 a 1999, oriundas de 201 rebanhos, sendo os registros de produção do serviço de controle leiteiro realizado pela Associação Brasileira de Criadores de Gado Pardo-Suíço. As lactações foram ajustadas por meio de fatores multiplicativos de ajustamento para duas ordenhas, períodos de lactação de 305 dias e produção a idade adulta. As médias estimadas, os respectivos desvios-padrão e os coeficientes de variação da produção de leite, produção de gordura e percentagem de gordura foram 5791,50 ± 1211,58 kg e 20,92%; 217,25 ± 47,36 kg e 21,80% e 3,78 ± 0,34 e 9,16%, respectivamente. Os efeitos de ano e época de partos, interação ano-época de partos, rebanho e grupo genético influenciaram as características estudadas, com exceção da época de partos sobre a percentagem de gordura. Os coeficientes de herdabilidade e repetibilidade estimados para a produção de leite e gordura foram 0,37e 0,40, e 0,36 e 0,37, respectivamente. A correlação genética entre a produção de leite e de gordura encontrada neste estudo foi de 0,96. Os resultados obtidos revelam a necessidade do ajustamento das produções de leite e gordura para os efeitos avaliados. As médias de produção de leite, de gordura e à percentagem de gordura apresentada demonstram o elevado desempenho produtivo da raça Pardo-Suíça nos rebanhos brasileiros.A study was carried on performance of the Brown Swiss cattle with the objective of estimating adjustment factors, evaluate some environment and genetics factors that affect milk and fat yields and fat percentage, and estimate

  9. A simple method for the separation and quantitation of radiolabeled thyroid hormones in thyroxine clearance studies

    International Nuclear Information System (INIS)

    A method was developed to facilitate the separation and quantitation of radiolabeled thyroxine in plasma for thyroxine clearance studies. Following intravenous injection of radioactive thyroxine, the radiolabeled thyroid hormones were isolated from plasma protein and polar metabolites by solid phase extraction on a C18 sorbent bed. The individual thyroid hormones were then separated by ion-pair reversed phase chromatography and sequentially eluted through a UV detector and radiochromatographic detector. The radioactivity of individual radiolabeled thyroid hormones was corrected for recovery of carrier as determined from UV absorbance. The recoveries of thyroxine and 3,5,3'-triiodothyronine (T3) were 96% and 101%, respectively

  10. Assessment of a method for measuring serum thyroxine by radioimmunoassay, with use of polyethylene glycol precipitation

    International Nuclear Information System (INIS)

    We assessed the efficacy of a new thyroxine radioimmunoassay kit (Abbott) in which polyethylene glycol is used to separate bound from free hormone. Mean serum thyroxine was 88 +- 15 (+-SD) μg/liter for 96 normal persons. Results for hypothyroid and hyperthyroid persons were clearly separated from those for normal individuals. Women taking oral contraceptive preparations showed variable increases in their serum thyroxine values. The coefficient of variation ranged from 1 to 3% within assay and from 5.4 to 11% among different assays. Excellent parallelism was demonstrated between thyroxine values estimated by this method and those obtained either by competitive protein binding or by a separate radioimmunoassay for the hormone

  11. Reduction of FDG uptake in brown adipose tissue in clinical patients by a single dose of propranolol

    International Nuclear Information System (INIS)

    Uptake in brown adipose tissue (hibernating fat) is sometimes seen at FDG-PET examinations. Despite a characteristic appearance, this may hide clinically relevant uptake. Stimulation of the sympathetic nervous system increases glucose uptake of brown fat. We now re-examine patients with brown fat activity that could disguise tumour uptake after pre-treatment with propranolol (a non-selective β-blocker) in order to reduce the uptake. Our first examinations of this kind are reported. Eleven patients with strong brown fat uptake were studied. There was a mean of 5 days (range 2-8) between the examinations. At the second examination, 80 mg of propranolol was given orally 2 h before FDG administration. In addition to visual evaluation of the brown fat uptake, SUV assessments of the uptake in brown fat, lung, heart, liver, spleen and bone marrow were made. All patients showed complete or almost complete disappearance of the brown fat activity at the second examination (p < 0.001) both upon visual evaluation and when comparing SUVs. In seven patients there was also uptake in a known or strongly suspected malignancy, which remained unchanged between the examinations. Beyond an insignificant decrease in the myocardial uptake, there was no redistribution to the various examined organs at the second examination. Pre-treatment with a single dose of propranolol blocks the FDG uptake in brown adipose tissue, thereby increasing the specificity of the examination. The tumour uptake seems not to be impaired. (orig.)

  12. Neurocognitive function in children with compensated hypothyroidism: lack of short term effects on or off thyroxin

    Directory of Open Access Journals (Sweden)

    Bracken Stacey

    2006-03-01

    Full Text Available Abstract Background Although thyroxin therapy clearly is beneficial to children with frank hypothyroidism there is little data on the effects of thyroxin in children with compensated or subclinical hypothyroidism. The objective of this study was to determine the effect of thyroxin therapy on cognitive function in children with compensated hypothyroidism. The hypothesis was that thyroxin therapy would change neuropsychological function. Methods Eleven patients with a history of sub clinical hypothyroidism entered the study. At the start of the study, six out of the 11 were on thyroxin therapy, while 5 were off therapy. All patients underwent a battery of neuropsychological testing and thyroid function tests at the start of study. Based on the results of thyroid function tests, two of the 5 patients who were off thyroxin were started back on thyroxin. All of the 6 patients who were on thyroxin were taken off thyroxin. All patients then underwent repeat neuropsychological testing and thyroid functions after an average of 91 days. Results Thyroxin therapy could not be shown to have an effect on neuropsychological function in this short term study. Our patients had attention problems as compared to the normal population. No significant differences were found between our subjects and normal population standards in verbal processing, visual processing, motor speed/coordination and achievement. Conclusion In this small, short term study, thyroxin therapy could not be shown to affect neuropsychological function in children with compensated hypothyroidism. These children may have attention problems but appear to have normal verbal and visual processing, motor speed/coordination and achievement.

  13. Treating Hypothyroidism with Thyroxine/Triiodothyronine Combination Therapy in Denmark

    DEFF Research Database (Denmark)

    Michaelsson, Luba Freja; Medici, Bjarke Borregaard; la Cour, Jeppe Lerche;

    2015-01-01

    BACKGROUND: Five to ten percent of patients with hypothyroidism describe persistent symptoms despite being biochemically well regulated on levothyroxine (L-T4). Thyroxine (T4)/triiodothyronine (T3) combination therapy [L-T4/liothyronine (L-T3) or desiccated thyroid] are still regarded as...... after a patient published a book describing her experiences with hypothyroidism and treatment. OBJECTIVE: To investigate current Danish trends in the use of T4/T3 combination therapy. METHODS: We used an Internet-based questionnaire, distributed as a link via two Danish patient fora. Further...

  14. Salsalate activates brown adipose tissue in mice.

    Science.gov (United States)

    van Dam, Andrea D; Nahon, Kimberly J; Kooijman, Sander; van den Berg, Susan M; Kanhai, Anish A; Kikuchi, Takuya; Heemskerk, Mattijs M; van Harmelen, Vanessa; Lombès, Marc; van den Hoek, Anita M; de Winther, Menno P J; Lutgens, Esther; Guigas, Bruno; Rensen, Patrick C N; Boon, Mariëtte R

    2015-05-01

    Salsalate improves glucose intolerance and dyslipidemia in type 2 diabetes patients, but the mechanism is still unknown. The aim of the current study was to unravel the molecular mechanisms involved in these beneficial metabolic effects of salsalate by treating mice with salsalate during and after development of high-fat diet-induced obesity. We found that salsalate attenuated and reversed high-fat diet-induced weight gain, in particular fat mass accumulation, improved glucose tolerance, and lowered plasma triglyceride levels. Mechanistically, salsalate selectively promoted the uptake of fatty acids from glycerol tri[(3)H]oleate-labeled lipoprotein-like emulsion particles by brown adipose tissue (BAT), decreased the intracellular lipid content in BAT, and increased rectal temperature, all pointing to more active BAT. The treatment of differentiated T37i brown adipocytes with salsalate increased uncoupled respiration. Moreover, salsalate upregulated Ucp1 expression and enhanced glycerol release, a dual effect that was abolished by the inhibition of cAMP-dependent protein kinase (PKA). In conclusion, salsalate activates BAT, presumably by directly activating brown adipocytes via the PKA pathway, suggesting a novel mechanism that may explain its beneficial metabolic effects in type 2 diabetes patients. PMID:25475439

  15. A role of active brown adipose tissue in cancer cachexia?

    OpenAIRE

    Emiel Beijer; Janna Schoenmakers; Guy Vijgen; Fons Kessels; Anne-Marie Dingemans; Patrick Schrauwen; Miel Wouters; Wouter van Marken Lichtenbelt; Jaap Teule; Boudewijn Brans

    2012-01-01

    Until a few years ago, adult humans were not thought to have brown adipose tissue (BAT). Now, this is a rapidly evolving field of research with perspectives in metabolic syndromes such as obesity and new therapies targeting its bio-energetic pathways. White, brown and socalled brite adipose fat seem to be able to trans-differentiate into each other, emphasizing the dynamic nature of fat tissue for metabolism. Human and animal data in cancer cachexia to date provide some evidence for BAT activ...

  16. Age and Sex Mediated Changes in Epicardial Fat Adipokines

    OpenAIRE

    Fei, Jia; Cook, Carla; BLOUGH, ERIC; Santanam, Nalini

    2010-01-01

    Aging, which is an independent risk factor for heart disease, alters body fat mass and its function. Epicardial fat plays an important physiological and pathophysiological role on cardiac structure and function. This study investigated if aging altered the abundance of epicardial (EF) and abdominal fat (AF) derived mediators in a sex dependent manner in female and male Fischer 344 × Brown Norway hybrid (FBN) rats. EF and AF were obtained from 48 female and male, young (6 months), aged (26/30 ...

  17. Atmospheres of Brown Dwarfs

    CERN Document Server

    Helling, Christiane

    2014-01-01

    Brown Dwarfs are the coolest class of stellar objects known to date. Our present perception is that Brown Dwarfs follow the principles of star formation, and that Brown Dwarfs share many characteristics with planets. Being the darkest and lowest mass stars known makes Brown Dwarfs also the coolest stars known. This has profound implication for their spectral fingerprints. Brown Dwarfs cover a range of effective temperatures which cause brown dwarfs atmospheres to be a sequence that gradually changes from a M-dwarf-like spectrum into a planet-like spectrum. This further implies that below an effective temperature of < 2800K, clouds form already in atmospheres of objects marking the boundary between M-Dwarfs and brown dwarfs. Recent developments have sparked the interest in plasma processes in such very cool atmospheres: sporadic and quiescent radio emission has been observed in combination with decaying Xray-activity indicators across the fully convective boundary.

  18. AHNAK deficiency promotes browning and lipolysis in mice via increased responsiveness to β-adrenergic signalling

    OpenAIRE

    Jae Hoon Shin; Seo Hyun Lee; Yo Na Kim; Il Yong Kim; Youn Ju Kim; Dong Soo Kyeong; Hee Jung Lim; Soo Young Cho; Junhee Choi; Young Jin Wi; Jae-Hoon Choi; Yeo Sung Yoon; Yun Soo Bae; Je Kyung Seong

    2016-01-01

    In adipose tissue, agonists of the β3-adrenergic receptor (ADRB3) regulate lipolysis, lipid oxidation, and thermogenesis. The deficiency in the thermogenesis induced by neuroblast differentiation-associated protein AHNAK in white adipose tissue (WAT) of mice fed a high-fat diet suggests that AHNAK may stimulate energy expenditure via development of beige fat. Here, we report that AHNAK deficiency promoted browning and thermogenic gene expression in WAT but not in brown adipose tissue of mice ...

  19. Brown Adipose Tissue: A New Target for Antiobesity Therapy

    OpenAIRE

    Anna Meiliana; Andi Wijaya

    2010-01-01

    BACKGROUND: Human fat consist of white and brown adipose tissue (WAT and BAT). Though most fat is energy-storing WAT, the thermogenic capacity of even small amounts of BAT makes it an attractive therapeutic target for inducing weight loss through energy expenditure. CONTENT: Over the past year, several independent research teams used a combination of positron-emission tomography and computed tomography (PET/CT) imaging, immunohistochemistry and gene and protein expression assays to prove conc...

  20. Browning of white adipose tissue: role of hypothalamic signaling

    OpenAIRE

    Bi, Sheng; Li, Lin

    2013-01-01

    Two types of fat, white adipose tissue (WAT) and brown adipose tissue (BAT), exist in mammals including adult humans. While WAT stores excess calories and an excessive accumulation of fat causes obesity, BAT dissipates energy to produce heat through non-shivering thermogenesis for protection against cold environments and provides the potential for the development of novel anti-obesity treatments. The hypothalamus plays a central role in the control of energy balance. Specifically, recent obse...

  1. Turning up the heat : role of brown adipose tissue in metabolic disease

    NARCIS (Netherlands)

    Boon, Mariëtte Rebecca

    2014-01-01

    In 1551, the Swiss naturalist Konrad Gessner first described brown adipose tissue (BAT) as being “neither fat, nor flesh (nec pinguitudo, nec caro), but something in between”. Now, some 460 years later, we know that Gessner had guessed the origin of brown adipocytes correctly. A unique property of t

  2. Control and Physiological Determinants of Sympathetically Mediated Brown Adipose Tissue Thermogenesis

    OpenAIRE

    DenisRichard; ÉricTurcotte

    2012-01-01

    Brown adipose tissue (BAT) represents a remarkable heat-producing tissue. The thermogenic potential of BAT is conferred by uncoupling protein 1, a protein found uniquely in the brown adipocytes. The physiological control of BAT activity and capacity is ensured by the sympathetic nervous system (SNS), which densely innervates brown fat depots. SNS-mediated BAT thermogenesis is essentially governed by hypothalamic and brainstem neurons. BAT is not only controlled by the brain thermoregulatory c...

  3. Role of Vascular Endothelial Growth Factor Signaling in Brown Adipocyte Survival, Proliferation and Function

    OpenAIRE

    Bagchi, Mandrita

    2012-01-01

    Both white and brown adipose tissues exhibit extensive vascularity. Increased angiogenesis in brown adipose tissue (BAT) is crucial for brown fat activation and thermogenesis in animals during cold acclimation. BAT can be similarly activated by food intake to generate heat through cellular respiration, in a process known as diet induced thermogenesis. Vascular endothelial growth factor (VEGF) is a potent angiogenic factor that regulates both pathological and physiological angiogenesis and can...

  4. Temperature-responsive release of thyroxine and its environmental adaptation in Australians

    Science.gov (United States)

    Qi, Xiaoqiang; Chan, Wee Lee; Read, Randy J.; Zhou, Aiwu; Carrell, Robin W.

    2014-01-01

    The hormone thyroxine that regulates mammalian metabolism is carried and stored in the blood by thyroxine-binding globulin (TBG). We demonstrate here that the release of thyroxine from TBG occurs by a temperature-sensitive mechanism and show how this will provide a homoeostatic adjustment of the concentration of thyroxine to match metabolic needs, as with the hypothermia and torpor of small animals. In humans, a rise in temperature, as in infections, will trigger an accelerated release of thyroxine, resulting in a predictable 23% increase in the concentration of free thyroxine at 39°C. The in vivo relevance of this fever-response is affirmed in an environmental adaptation in aboriginal Australians. We show how two mutations incorporated in their TBG interact in a way that will halve the surge in thyroxine release, and hence the boost in metabolic rate that would otherwise occur as body temperatures exceed 37°C. The overall findings open insights into physiological changes that accompany variations in body temperature, as notably in fevers. PMID:24478298

  5. Pituitary hyperplasia: a complication of the pseudomalabsorption of thyroxine

    Directory of Open Access Journals (Sweden)

    Doyle MA

    2013-04-01

    Full Text Available Mary-Anne Doyle, Heather A Lochnan Division of Endocrinology, University of Ottawa, Ottawa, ON, Canada Objective: “The pseudomalabsorption of thyroxine” has been used to describe patients with hypothyroidism who fail to comply with their treatment. We describe a unique case of a 32-year-old with hypothyroidism who developed pituitary hyperplasia and hyperprolactinemia secondary to the pseudomalabsorption of thyroxine. Investigations and treatment: After baseline thyroid-function tests were performed, the patient was administered levothyroxine 0.5 mg under the supervision of a registered nurse. Thyroid function testing was repeated at 30, 60, 120, and 180 minutes. Arrangements were made for further daily supervised loading of levothyroxine 0.1 mg. Results: With the administration of 0.5 mg levothyroxine, free thyroxine levels increased by 120 minutes, and with daily supervised dosing of 0.1 mg there was normalization of the thyroid hormone levels and a reduction of thyroid-stimulating hormone levels. Maintenance of thyroid-stimulating hormone < 15 mU/L for 2 weeks led to a reduction in prolactin levels and regression in the size of the pituitary on magnetic resonance imaging. Conclusion: If left untreated, these patients face significant morbidity and are at risk of developing pituitary hyperplasia, complications from an increase in pituitary size, hyperprolactinemia, and potentially myxedema coma. Recognizing pituitary hyperplasia and hyperprolactinemia as a complication from the pseudomalabsorption of levothyroxine may prevent the potential of a misdiagnosis of a prolactinoma leading to unnecessary investigations and inappropriate treatment. Patient awareness of this serious complication and the rapid, demonstrable resolution with adequate thyroid hormone replacement may provide motivation to comply with supervised dosing of levothyroxine. It has also been suggested that supervised treatment enables the individual to maintain their patient

  6. The Relationship Between Thyroxine Level and Short Term Clinical Outcome Among Sick Newborn Infants

    Directory of Open Access Journals (Sweden)

    Maliheh Kadivar

    2011-02-01

    Full Text Available Premature and critically sick infants frequently experience several interventions, including blood transfusions, parentral nutrition, and prescriptions during hospitalization that could affect the result of thyroid function test. This study aims to investigate the correlation between thyroxine level and clinical short term outcome among the newborn infants in the neonatal intensive care unit (NICU. We assessed serum levels of thyroxine and thyroid stimulating hormone of 99 neonates who were admitted in the NICU from September 1st 2004 to March 30th 2005. Number of patients with low thyroxin level (less than 6.5 µg/dl was determined and the relation between serum total thyroxine level and birth weight, gestational age, duration of hospitalization, clinical diagnosis, and final outcome was investigated. Short term outcome was considered as duration of hospitalization and discharge alive from hospital. Prevalence of hypothyroxinemia was 26 percent. Later assessment of thyroxine level within 3 weeks revealed normal level of this parameter (8.12 µg/dl ±1.36. Patients with lower gestational age and lower birth weight had lower thyroxine level (7.15 µg/dl ±2.56, and P=0.03, 6.72 µg/dl ±3.03, and P=0.08. Low thyroxine level was not associated with adverse short-term clinical outcome (mortality rates; 3(11% and 9(12%, and duration of hospitalization among 17.7±9.8 vs 16.7± 13.0 in patients with hypothyroxinemia and low thyroxine level respectively. Hypothyroxinemia has considerable prevalence in neonatal intensive care setting and is related with lower birth weight and gestational age. Whether thyroxin levels are a marker or mediator of short term clinical outcome remains to be determined by further studies.

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

    Science.gov (United States)

    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...

  8. Controlled cellular energy conversion in brown adipose tissue thermogenesis

    Science.gov (United States)

    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.

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

    Science.gov (United States)

    Suárez-Zamorano, Nicolas; Fabbiano, Salvatore; 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

    2015-12-01

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

  10. Estrogens increase expression of bone morphogenetic protein 8b in brown adipose tissue of mice

    NARCIS (Netherlands)

    A. Grefhorst (Aldo); J.C. van den Beukel (Johanna); A.F. van Houten (A.); J. Steenbergen (Jacobie); J.A. Visser (Jenny); A.P.N. Themmen (Axel)

    2015-01-01

    textabstractBackground: In mammals, white adipose tissue (WAT) stores fat and brown adipose tissue (BAT) dissipates fat to produce heat. Several studies showed that females have more active BAT. Members of the bone morphogenetic protein (BMP) and fibroblast growth factor (FGF) families are expressed

  11. Saturated fat (image)

    Science.gov (United States)

    ... saturated fats. Vegetable sources of saturated fat include coconut and palm oils. When looking at a food ... saturated fats. Vegetable sources of saturated fat include coconut and palm oils. When looking at a food ...

  12. Father Brown, Selected sories

    NARCIS (Netherlands)

    Chesterton, G.K.

    2005-01-01

    Father Brown, a small, round Catholic priest with a remarkable understanding of the criminal mind, is one of literature's most unusual and endearing detectives, able to solve the strangest crimes in a most fascinating manner. This collection draws from all five Father Brown books, and within their r

  13. Effect of the slow (K or rapid (k+ feathering gene on body and feather growth and fatness according to ambient temperature in a Leghorn × brown egg type cross

    Directory of Open Access Journals (Sweden)

    Bordas André

    2001-11-01

    Full Text Available Abstract Chicks of both sexes issued from the cross of heterozygous K/k+ cocks for the slow-feathering sex linked K allele with k+ (rapid feathering hens, were compared from the age of 4 to 10 weeks at two ambient temperatures. In individual cages, 30 male chicks of each genotype (K/k+ and k+/k+ were raised at 21°C, and 60 others, distributed in the same way, were raised at 31°C. 71 K/W females and 69 k+/W females were raised in a floor pen at 31°C till 10 weeks of age. In the males, the body weight, feed consumption and feed efficiency at different ages were influenced only by temperature (lower growth rate and feed intake at 31°C; no significant effects of the genotype at locus K nor genotype × temperature interaction were observed. In females, all at 31°C, the genotype (K/W or k+/W had no significant effect on growth rate. Plumage weight and weight of abdominal fat (absolute or related to body weight were measured on half of the males of each group in individual cages, at 10 weeks of age. Moreover, on 36 males and 48 females of the two genotypes, in a group battery at 31°C, the absolute and relative weight of plumage were measured on a sample every two weeks between 4 and 10 weeks. In the first case, no significant effect of genotype appeared. In the second case, an interaction between age and genotype was suggested from plumage weight: its growth, especially in male chicks, appears to be temporarily and unexpectedly faster from 4 to 6 weeks of age for the K/k+ and K/W genotypes.

  14. Effect of anaethesia and surgery on plasma cortisol, insulin and total thyroxin

    International Nuclear Information System (INIS)

    The effect of anaesthesia and surgery on plasma levels of cortisol, insulin and total thyroxin measured by radio-immunoassay was carried out on 12 patients undergoing elective surgery. During premedication, plasma cortisol and total thyroxin levels showed no change while plasma insulin showed a slight decline and blood sugar showed a light rise. During anaesthesia minimal changes were noticed in all parameters. During surgery significant rises in cortisol and thyroxin levels occurred and persisted post-operatively. Plasma insulin and blood sugar showed minimal fluctuations during surgery with a tendency to rise post-operatively. It is concluded that: 1) Effective premedication can suppress adrenocortical response during anaesthesia. 2) A rise in insulin level at the end of surgery may be gradual and parallel with a rise in blood sugar level. 3) An increased total thyroxin level during general anaesthesia and surgery may be a separate stress response, not due to stress induced increased glucocorticoids

  15. A simple ligand-binding assay for thyroxine-binding globulin on reusable Sephadex columns

    International Nuclear Information System (INIS)

    A method for the assay of thyroxine-binding globulin on reusable Sephadex G-25 columns is described. It depends upon elution by diluted iodothyronine-free serum of protein-bound [125I]thyroxine from the columns under conditions where binding to thyroxine-binding prealbumin and albumin are abolished. It is simple, rapid and precise, and permits determinations inlarge numbers of samples. Values (mg/l; mean +- S.D.) were: normals 31.6+-5.4, hyperthyroid 28.3+-4.8, hypothyroid 40.6+-7.5, oral contraceptives 40.1+-6.8, pregnant 50.3+-5.4, cirrhotics 20.7+-4.3. Concentrations were reduced in serum heated at 56degC, while the uptake of [125I]triiodothyronine was increased. There was a significant negative correlation between thyroxine-binding globulin concentration and triiodothyronine uptake in the heated serum samples and in euthyroid subjects

  16. Emulsion Mapping in Pork Meat Emulsion Systems with Various Lipid Types and Brown Rice Fiber

    OpenAIRE

    Choi, Yun-Sang; Kim, Young-Boong; Kim, Hyun-Wook; Hwang, Ko-Eun; Song, Dong-Heon; Jeong, Tae-Jun; Park, Jinhee; Kim, Cheon-Jei

    2015-01-01

    This study was conducted to evaluate emulsion mapping between emulsion stability and cooking yields, apparent viscosity, and hardness of reduced-fat pork emulsion systems. The reduced-fat emulsion systems were supplemented with different lipid types and brown rice bran fiber (BRF) concentrations. Compared to the control with 30% back fat, lower emulsion stability and higher cooking yield of meat emulsion systems were observed in T1 (30% back fat+1% BRF), T2 (30% back fat+2% BRF), T3 (30% back...

  17. Thyroxine, methimazole, and thyroid microsomal autoantibody titres in hypothyroid Hashimoto's thyroiditis.

    OpenAIRE

    Jansson, R.; Karlsson, A; Dahlberg, P A

    1985-01-01

    Ten hypothyroid patients with Hashimoto's thyroiditis were treated with methimazole 30 mg in addition to thyroxine 0.15 mg daily. Another 10 hypothyroid patients with Hashimoto's thyroiditis were given thyroxine 0.15 mg alone. After 22 weeks of treatment significant decreases in thyroid microsomal autoantibody titres were observed in both groups (p less than 0.01). There was no difference in the mean change in titre between the two groups. When the patients treated with methimazole were subse...

  18. Homocysteine and Fibrinogen Changes with L-thyroxine in Subclinical Hypothyroid Patients

    OpenAIRE

    Çakal, Başak; Çakal, Erman; Demirbaş, Berrin; ÖZKAYA, Mesut; Karaahmetoğlu, Selma; Serter, Rüştü; Aral, Yalçin

    2007-01-01

    The aim of the present study was to evaluate plasma total homocysteine (Hcys) and serum fibrinogen concentrations in subclinical hypothyroid (SH) and overt hypothyroid patients before and after L-thyroxine (LT4) replacement and to compare them in euthyroid subjects. Fifteen SH and 20 hypothyroid premenopausal women were recruited in the study. We measured fasting plasma levels of Hcys and serum levels of free thyroxine (fT4), free triiodothyronine (fT3), thyrotropin (TSH), folate, vitamin B12...

  19. Fat Attenuation at CT in Anorexia Nervosa.

    Science.gov (United States)

    Gill, Corey M; Torriani, Martin; Murphy, Rachel; Harris, Tamara B; Miller, Karen K; Klibanski, Anne; Bredella, Miriam A

    2016-04-01

    Purpose To investigate the composition, cross-sectional area (CSA), and hormonal correlates of different fat depots in women with anorexia nervosa (AN) and control subjects with normal weights to find out whether patients with AN have lower fat CSA but higher attenuation than did control subjects and whether these changes may be mediated by gonadal steroids, cortisol, and thyroid hormones. Materials and Methods This study was institutional review board approved and HIPAA compliant. Written informed consent was obtained. Forty premenopausal women with AN and 40 normal-weight women of comparable age (mean age ± standard deviation, 26 years ± 5) were studied. All individuals underwent computed tomography of the abdomen and thigh with a calibration phantom. Abdominal subcutaneous adipose tissue (SAT), visceral adipose tissue (VAT), thigh SAT, and thigh intermuscular adipose tissue CSA and attenuation were quantified. Serum estradiol, thyroid hormones, and urinary free cortisol levels were assessed. Variables were compared by using analysis of variance. Associations were examined by using linear regression analysis. Results Women with AN had higher fat attenuation than did control subjects (-100.1 to -46.7 HU vs -117.6 to -61.8 HU, P < .0001), despite lower fat CSA (2.0-62.8 cm(2) vs 5.5-185.9 cm(2), P < .0001). VAT attenuation but not CSA was inversely associated with lowest prior lifetime body mass index in AN (r = -0.71, P = .006). Serum estradiol levels were inversely associated with fat attenuation (r = -0.34 to -0.61, P = .03 to <.0001) and were positively associated with fat CSA of all compartments (r = 0.42-0.64, P = .007 to <.0001). Thyroxine levels and urinary free cortisol levels were positively associated with thigh SAT attenuation (r = 0.64 [P = .006] and r = 0.68 [P = .0004], respectively) and were inversely associated with abdominal SAT and VAT CSA (r = -0.44 to -0.58, P = .04 to .02). Conclusion Women with AN have differences in fat composition, with

  20. Regulatory circuits controlling white versus brown adipocyte differentiation

    DEFF Research Database (Denmark)

    Hansen, Jacob B; Kristiansen, Karsten

    2006-01-01

    Adipose tissue is a major endocrine organ that exerts a profound influence on whole-body homoeostasis. Two types of adipose tissue exist in mammals: WAT (white adipose tissue) and BAT (brown adipose tissue). WAT stores energy and is the largest energy reserve in mammals, whereas BAT, expressing UCP......1 (uncoupling protein 1), can dissipate energy through adaptive thermogenesis. In rodents, ample evidence supports BAT as an organ counteracting obesity, whereas less is known about the presence and significance of BAT in humans. Despite the different functions of white and brown adipocytes......, knowledge of factors differentially influencing the formation of white and brown fat cells is sparse. Here we summarize recent progress in the molecular understanding of white versus brown adipocyte differentiation, including novel insights into transcriptional and signal transduction pathways. Since...

  1. ASK1 signalling regulates brown and beige adipocyte function.

    Science.gov (United States)

    Hattori, Kazuki; Naguro, Isao; Okabe, Kohki; Funatsu, Takashi; Furutani, Shotaro; Takeda, Kohsuke; Ichijo, Hidenori

    2016-01-01

    Recent studies suggest that adult humans have active brown or beige adipocytes, the activation of which might be a therapeutic strategy for the treatment of diverse metabolic diseases. Here we show that the protein kinase ASK1 regulates brown and beige adipocytes function. In brown or white adipocytes, the PKA-ASK1-p38 axis is activated in response to cAMP signalling and contributes to the cell-autonomous induction of genes, including Ucp1. Global and fat-specific ASK1 deficiency leads to impaired metabolic responses, including thermogenesis and oxygen consumption, at the cell and whole-body levels, respectively. Our data thus indicate that the ASK1 signalling axis is a regulator of brown and beige adipocyte gene expression and function. PMID:27045525

  2. Correction of Hypothyroidism Seems to Have No Effect on Body Fat

    OpenAIRE

    Okan Bakiner; Emre Bozkirli; Emine Duygu Ersozlu Bozkirli; Kursat Ozsahin

    2013-01-01

    Aim. We aimed to observe the effects of L-thyroxine replacement therapy on body fat content determined with various anthropometric methods and a bioelectrical impedance analysis method in patients with hypothyroidism. Methods. Forty-two women with naive autoimmune hypothyroidism were included. Also, 40 healthy participants were enrolled as a control group. Weight, body mass index, waist circumference, and subscapulary, suprailiac, femur, biceps, and triceps skin fold thicknesses were measured...

  3. The relationship between thyroxine secretion rate and egg production in chicken

    International Nuclear Information System (INIS)

    An experiment was carried out in 24 female White Leghorn Chickens by using 131I as tracer. The chickens were initially and intraperitoneally injected with 10μCi of 131I and then counted by means of a Gamma Well Type Scintillation Counter every 48 hours. A dose of 0,3 μg of thyroxine per 100 gr body weight was given as the first administration. After every two administrations of similar dose, the dose of the thyroxine was increased by 0,1 μg/100g body weight until the thyroxine secretion rate was reached. The injections were given in the neck region subcutaneously. The thyroxine secretion rate was found to be within the range from 0,5μg to 0,8μg per 100 g body weight. It also showed that the higher the thyroxine secretion rate, the higher the egg production became. This phenomenon occured both with the 7 and 9 months old chickens. However there was neither ralationship between the thyroxine secretion rate and the weight of eggs produced nor with the body weight of the chickens themselves. (author)

  4. Production and use of thyroxine antisera in radioimmunoassay technique

    International Nuclear Information System (INIS)

    This study describes the production of antisera from sheep and its use in the determination of thyroxine hormone (T4) level in serum using radioimmunoassay (RIA) technique. In this study two local sheep (Ovis aris) were subjected to immunization against human T4 immunogen, sera obtained from both sheep after each injection were subjected to evaluation through titration in a purified and non purified form. The produced antibodies were used to assemble a kit for the determination of total human serum thyroxine. Different separation techniques were tried, (second antibody polyethylene glycol (PEG) assisted precipitation, polystyrene beads and magnetisable particles solid phases). For the PEG assisted precipitation, local antiserum and that produced by the North East Thamus Region Immunoassay (NETRIA donkey anti-sheep serum (DASS) as second antibodies) were tried. The final dilutions of the anti-T4 antibody used were 1/4000 in a liquid phase using second antibody PEG assisted separation, 1/3000 using magnetizable particles and a dilution of 1/10,000 using polystyrene beads solid phase for separation. Optimization of T4 assay conditions including incubation temperature and reaction time were done. Tests for T4 assay validation (linearity, recovery and responsibility) were carried out. For linearity and recovery tests, the regression coefficient ranges were found to be from (0.8 to 0.9) and (0.88 to 0.98) respectively. The assay was found to be reproducible where the coefficients of variation within and between assays were less than 10%. The locally developed assay was found to be comparable with NETRIA assay as a reference method with a correlation coefficient of 0.88, 0.93 and 0.87 for PEG assisted separation, magnetizable particles and polystyrene beads techniques respectively. The clinical validation tests showed a reliable sensitivity, specificity and efficiency with values of 97%, 94% and 96% respectively. When the T4 concentrations measured using the locally

  5. The brown adipocyte differentiation pathway in birds: An evolutionary road not taken

    Directory of Open Access Journals (Sweden)

    Kumaratilake Jaliya S

    2008-04-01

    Full Text Available Abstract Background Thermogenic brown adipose tissue has never been described in birds or other non-mammalian vertebrates. Brown adipocytes in mammals are distinguished from the more common white fat adipocytes by having numerous small lipid droplets rather than a single large one, elevated numbers of mitochondria, and mitochondrial expression of the nuclear gene UCP1, the uncoupler of oxidative phosphorylation responsible for non-shivering thermogenesis. Results We have identified in vitro inductive conditions in which mesenchymal cells isolated from the embryonic chicken limb bud differentiate into avian brown adipocyte-like cells (ABALCs with the morphological and many of the biochemical properties of terminally differentiated brown adipocytes. Avian, and as we show here, lizard species lack the gene for UCP1, although it is present in amphibian and fish species. While ABALCs are therefore not functional brown adipocytes, they are generated by a developmental pathway virtually identical to brown fat differentiation in mammals: both the common adipogenic transcription factor peroxisome proliferator-activated receptor-γ (PPARγ, and a coactivator of that factor specific to brown fat differentiation in mammals, PGC1α, are elevated in expression, as are mitochondrial volume and DNA. Furthermore, ABALCs induction resulted in strong transcription from a transfected mouse UCP1 promoter. Conclusion These findings strongly suggest that the brown fat differentiation pathway evolved in a common ancestor of birds and mammals and its thermogenicity was lost in the avian lineage, with the degradation of UCP1, after it separated from the mammalian lineage. Since this event occurred no later than the saurian ancestor of birds and lizards, an implication of this is that dinosaurs had neither UCP1 nor canonically thermogenic brown fat.

  6. Dichoptic perception of brown.

    Science.gov (United States)

    DeLawyer, Tanner; Morimoto, Takuma; Buck, Steven L

    2016-03-01

    Two experiments assessed mechanisms underlying brown induction by presenting a foveal target disk and concentric annular surround stimuli that varied in contrast relative to larger backgrounds. Stimuli were presented under monocular, binocular, and dichoptic viewing conditions. Observers adjusted the luminance of the target disk to a criterion brown level. We found evidence for at least two separate mechanisms for brown induction: one mechanism that is dependent on physically contiguous contrast and operates in monocular pathways and another mechanism that responds to high luminance contrast anywhere in the visual field and can operate after convergence of signals from the two eyes. PMID:26974916

  7. Oxygen diffusion distance in thyroxine-induced hypertrophic rabbit myocardium.

    Science.gov (United States)

    Seiden, D; Navidad, P; Weiss, H R

    1988-10-01

    We studied the oxygen diffusion distance in the rabbit myocardium in untreated animals and in animals treated with thyroxine (T4) for 3 days and 16 days. The subepicardial and subendocardial regions were studied separately. Sixteen days of T4 treatment results in significant cardiac hypertrophy. After 16 days, the percentage of the myocardium occupied by myocytes decreases as the volume of extracellular matrix increases. After 3 days, the number of myocyte mitochondria per unit volume of myocardium increases without an increase in mitochondrial volume. After 16 days the volume density of the myocyte mitochondria increases. Oxygen diffusion distance was determined by measuring the distance between the myocardial capillaries and the cardiomyocyte mitochondria. The deposition of extracellular matrix results in an increase in the distance between the myocardial capillaries and the myocytes. The distribution of the mitochondria within the myocytes remains unchanged resulting in an increased distance between the capillaries and the mitochondria, hence, an increased oxygen diffusion distance. There is some evidence that the mitochondria most distant from the capillaries are the mitochondria in which division is most frequent with T4 stimulation. This may be related to the relative deprivation of oxygen of these mitochondria. PMID:2975340

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

    Directory of Open Access Journals (Sweden)

    Fengliang Wang

    Full Text Available 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.

  9. Effect of Instant Cooked Giant Embryonic Rice on Body Fat Weight and Plasma Lipid Profile in High Fat-Fed Mice

    OpenAIRE

    Soo Im Chung; Tae Hyeong Kim; Rico, Catherine W.; Mi Young Kang

    2014-01-01

    The comparative effects of instant cooked rice made from giant embryo mutant or ordinary normal rice on body weight and lipid profile in high fat-fed mice were investigated. The animals were given experimental diets for seven weeks: normal control (NC), high fat (HF), and HF supplemented with instant normal white (HF-NW), normal brown (HF-NB), giant embryonic white (HF-GW), or giant embryonic brown (HF-GB) rice. The HF group showed markedly higher body weight, body fat, plasma and hepatic tri...

  10. Have we entered the brown adipose tissue renaissance?

    OpenAIRE

    Ravussin, E.; Kozak, L P

    2009-01-01

    In the 1970s and 1980s, it was observed that rodents could offset excess calories ingested when they were fed a human-like `cafeteria diet'. Although it was erroneously concluded that this so-called diet-induced thermogenesis was because of brown adipose tissue (BAT), it led to efforts to test whether variations in brown fat in humans may explain the susceptibility to obesity. However, from evidence on the inability of ephedrine or beta-3 adrenergic agonists to induce BAT thermogenesis, it wa...

  11. Competitive protein binding analysis for thyroxine using Sephadex column (Tetralute)

    International Nuclear Information System (INIS)

    The method of competitive protein binding analysis of thyroxine (T4) using Tetralute kit was evaluated. The net retention was decreased when the procedure of competition and separation was performed at a higher temperature but the final T4-I values were constant when the standard and test sera were treated identically. Coefficient of variation (C.V.) was 4% (within-assay) and 6% (between-assay) respectively. However, the T4-I values of pooled serum for quality control were slightly lower in earlier experiments in which correction factors (1.03--1.62 in 18 out of 21 assays) were necessary. T4-I values were determined by the Tetralute in 155 cases. They were as follows: 4.9+-0.8 μg/dl (euthyroid subjects), 6.4+-1.2 μg/dl (cord serum), 7.1+-1.1 μg/dl (pregnant women). 9.0+-3.6 μg/dl (trophoblastic disease), 13.3+-4.8 μg/dl (Graves' disease), 6.3+-1.6 μg/dl (Plummer's disease), 4-I values determined by Tetralute and Res-O-Mat T4 (r=0.96). Following oral administration of Telepaque the serum protein-bound iodine was markedly elevated, while the T4-I determined by Tetralute did not change. In vitro addition of diphenylhydantoin (500 μg/ml), salicylate (4 mg/ml) and phenobarbital (1 mg/ml) had no or little effect on T4 determination by Tetralute. A high concentration of benzbromarone (0.1 mg/ml) caused a higher value of T4-I determined by Tetralute when added to a TBG solution but there was only a slight increase when it was added to serum. (auth.)

  12. Role of beta adrenoceptors in the hypertrophic response to thyroxine

    International Nuclear Information System (INIS)

    The ability of beta-adrenoceptor blockade to reduce the hypertrophic response to thyroxine (T4, 0.5 mg/kg per day, s.c.) was tested in New Zealand white rabbits. Two beta-adrenergic blocking agents, one a full antagonist (propranolol, 9.6 mg/kg per day) and the other a partial agonist (pindolol, 0.96 mg/kg per day) were administered in combination with T4 in an effort to reduce myocardial hypertrophy. A 3 and 16 day group were generated to test the time course of the hypertrophic and receptor responses. Coronary blood flow was measured using radioactive microspheres, and beta-adrenoceptor number and affinity were measured using 125I(-) pindolol as the radioligand. T4 increased coronary blood flow to 1.95 times control values in the 3 day group and 2.2 times control levels in the 16 day group; beta-adrenoceptor number was increased similarly in 3 and 16 day groups to 1.9 times control Bmax levels. Heart weight (HW) to body weight (BW) ratios were significantly increased in only the 16 day group to 1.22 and 1.61 times control, respectively. Treatment with propranolol + T4 blunted the coronary blood flow increase, but receptor upregulation occurred to the same extent as with either substance alone. The HW/BW was increased to 1.49 times control. Pindolol + T4 did not decrease coronary blood flow but blocked beta-adrenoceptor upregulation. The HW was reduced to control levels and the HW/BW ratio was 1.40 times control and significantly decreased from T4 alone. Thus, pindolol was effective in reducing the hypertrophic response to T4, whereas propranolol was only moderately effective in doing so

  13. Role of β-adrenoceptors in thyroxine-induced hypertrophy

    International Nuclear Information System (INIS)

    The role of β-adrenoceptors in the development of thyroxine (T4)-induced hypertrophy was studied in New Zealand white rabbits. Radiolabelled microspheres were used to measure coronary blood flow, and (125I)-pindolol was used for Scatchard analysis of cardiac membranes to determine β-adrenoceptor density (B/sub max/) and affinity. After 16 d of T4, coronary blood flow (CBF) was elevated from 257 +/- 31 ml/min/100 g (mean +/- SD) to 530 +/- 152 and B/sub max/ increased from 24.0 +/- 6.2 fmol/mg membrane protein to 47.3 +/- 12.0. Heart weight (HW) was elevated 30%, and heart weight/body weight (HW/BW) increased 70% above control. T4 + propranolol (9 mg/kg/d) diminished CBF from levels seen with T4 alone, to 361 +/- 146 ml/min/100g. However B/sub max/ elevations were unchanged from values with T4. HW and HW/BW increases were insignificantly less than with T4 alone. CBF in T4 + pindolol (0.9 mg/kg/d) animals was similar to that with T4 alone, but B/sub max/ increases were prevented (32.0 +/- 11.0). HW and HW/BW were both lower than with T4 alone (153% of control). Thus, it appears that pindolol is more able to reverse some of the effects of T4 than is propranolol, possibly due to prevention of β-adrenoceptor upregulation as a result of its intrinsic sympathomimetic ability

  14. Development of reagents for radioimmunoassay of: triiodothyronine, thyroxine and thyrotrophin

    International Nuclear Information System (INIS)

    The radioimmunoassay (RIA) of thyroid hormones it is the but it frequents of all the studies carried out by RIA in the laboratories of Nuclear Medicine, these essays are carried out with imported reagents. In the ININ the reagents and the necessary methodology have been developed for the triiodothyronine (T3), thyroxine (T4) and thyrotrophin (TSH). The good titles of the antibodies (Ac) primary for each hormone were of 1:4,000; 1:750 and 1:1,500. The used separation system was of double Ac with PEG to 10%, with titles of 1:10 for the second Ac of lamb. The specific activity for 125-I-T3 and 125-I-T4 oscillate between 850 at 900 μCi / μ g: being this of 90 μ Ci /μg for TSH. To the first two hormones they were added 1-8 aniline naftalen sulfonic acid (ANS) to concentrations of 3 and 2 mg/ml respectively. As buffer for T3 and T4 it was used Tris-HCl pH 8.6 and PBS with normal serum of rabbit (SNC) for TSH. The standards got ready in buffer or free serum of thyroid hormones. The slope of the standard curves varied between -2.3 to -2.7 and the variation intra and inter assay among 4 to 10%. It is had at the moment in the ININ with standardized reagents for the RIA of T3, T4 and TSH, it is hoped to carry out tests in other laboratories and to establish the conditions of stability more appropriate to begin the preparation of pilot reagents. (Author)

  15. Advantage, disadvantage and selection of methods for thyroxine measurement

    International Nuclear Information System (INIS)

    Res-O-Mat thyroxine (T4) was chosen as competitive protein binding analysis (C PBA), and RIAMAT-T4 (St) and T4-RIAKIT (Sp) were chosen as radioimmunoassay (RIAs). Reproducibility of CPBA, St and Sp within assay were 5.8%(C.V.), 4.0%(C.V.), and 8.5%(C.V.) respectively, and the mean recovery rates were 92.2%, 100.7% and 96.1% respectively. T4 values measured by both RIAs correlated well with CPBA. The St was slightly lower, and the Sp was slightly higher than CPBA. The normal ranges for RIAs were 3.7-11.7μg% (St) and 4.6-15.2μg% (Sp). Diagnostic accuracy for the hyperthyroid state was 83.3% (CPBA), 85.7% (St) and 69.2% (Sp), and for euthyroid state was 92.0% (CPBA), 98.8% (St) and 95.7% (Sp). The diagnostic accuracy for hypothyroid state was lowest in all three methods. Cost performance, time performance and total time for single assay were analysed and mathematical equations were obtained from the actual assay for each method. When the number of samples per single assay was less than 10, CPBA was most economical in terms of cost and time performance and total time required. In assays of more than 20 samples, RIAs were efficient from each point of view. From the point of view of sample volume required, RIAs were most promising. The authors concluded that guides for selection of methods in T4 assays were as follows: A) CPBA was most efficient in local use, especially when less than 10 samples were frequently to be assayed. B) RIAs were efficient in batch processing more than 20 samples, especially in automated laboratories. (auth.)

  16. Cardiac left ventricular function before and during early thyroxine treatment in severe hypothyroidism.

    Science.gov (United States)

    Bernstein, R; Müller, C; Midtbø, K; Haug, E; Nakken, K F; Hertzenberg, L; Kjørstad, K E

    1991-12-01

    In some patients with severe hypothyroidism, thyroxine replacement therapy precipitates or aggravates angina pectoris, whereas in other patients angina pectoris is ameliorated or even cured. Cardiac function in eight severely hypothyroid patients was studied by means of radionuclide ventriculography (RNV) at rest and during supine bicycle exercise before thyroxine treatment, and repeated during treatment before and after administration of 160 mg of oral verapamil. There was an exercise-induced fall in left ventricular ejection fraction (LVEF) in two patients before therapy, and in two additional subjects after 17 d on suboptimal doses of thyroxine. Verapamil attenuated the fall and induced a significant increase in LVEF during exercise (P less than 0.014). No abnormal regional cardiac wall movement (RWM) was observed. After 2 months of thyroxine treatment, LVEF increased significantly during exercise both before and after verapamil (P less than 0.012 and P less than 0.005). These findings are indicative of reversible coronary artery dysfunction. We recommend that, if feasible, thyroxine should be supplemented with verapamil during the early phase of treatment. PMID:1748858

  17. Development and evaluation of a magnetic solid-phase radioimmunoassay for total human thyroxine (T4)

    International Nuclear Information System (INIS)

    In this study a simple and rapid magnetic solid-phase radioimmunoassay (RIA) for human thyroxine (T4) was developed using locally raised sheep thyroxine antibody and radioiodinated thyroxine (T4) tracer by chloramine-T method. The assay involves two hours incubation at ambient temperature rang (30 to 35 oC) associated with the antibody covalently linked by the easily performed carbonyldiimidazole (CDI) method to magnetic particles obtained from SIPAC. 0.1% triton with sodium azide used as a wash buffer. L-Thyroxine Na-salt peta hydrate from sigma was used for the preparation of standards and quality control sera. The coupled magnetic anti-T4 solid phase titrated in order to find out the suitable antibody concentration (titre) to be used in the assay. Optimizations followed by validation procedures were done. When correlated with kits imported from NETRIA and AMERSHAM, results were found to be highly comparable r=0.965 and p<0.05. Shelf life was also studied, so that the local prepared T4 RIA magnetic reagents can be used for the measurement of total human thyroxine with a very low cost compared to imported kits. (Author)

  18. Thyroid-Stimulating Hormone, Triiodotyronine and Thyroxine Concentrations and Their Relationship with Metabolic Parameters, Anthropometric Variables and Body Composition in Premenopausal Euthyroid Obese Women

    Directory of Open Access Journals (Sweden)

    Mahdieh Abbasalizad Farhangi

    2015-03-01

    Full Text Available Purpose: This study was performed to evaluate the potential relationships of thyroid hormones, metabolic parameters, and anthropometric variables with body composition in premenopausal women. Material and Method: A total of 84 women with a mean age of 35.12±8.11 years were investigated. Subjects with a history of diabetes, hyperthyroidism and hypothyroidism, chronic liver, and renal disease were excluded from the study. In all subjects, anthropometric parameters were evaluated and body composition was analyzed by bioelectrical impedance analysis (BIA. Fasting serum thyroid-stimulating hormone (TSH, triiodothyrionine (T3, thyroxine (T4, fasting blood glucose (FBG, total cholesterol (TC, triglyceride (TG, high-density lipoprotein cholesterol (HDL-C, C-reactive protein (CRP, and interleukin 6 (IL-6 were measured by enzymatic methods. Serum low-density lipoprotein cholesterol (LDL-C was determined by Friedewald formula. Results: Serum TSH, CRP and TC levels in obese subjects were significantly higher than in non-obese subjects (p<0.05. Serum TSH concentration was positively associated with waist to hip ratio (WHR and fat mass and, negatively associated with fat-free mass (p<0.05. There was also a positive relationship between T3 and TG and between T4 and LDL-C in all participants. In comparison of subjects with different body fat percentage, subjects with higher body fat had also higher amount of TSH concentrations (p=0.015. Discussion: Our results showed a relationship of fat mass and lipid profile with thyroid function in premenopausal women. Further researches are needed to clarify the nature and mechanism of these relationships.

  19. Macro fat and micro fat

    DEFF Research Database (Denmark)

    Li, Yanjun; Gaillard, Jonathan R; McLaughlin, Tracey;

    2015-01-01

    The adipose cell-size distribution is a quantitative characterization of adipose tissue morphology. At a population level, the adipose cell-size distribution is insulin-sensitivity dependent, and the observed correlation between obesity and insulin resistance is believed to play a key role in the...... individuals, separated into 4 subgroups according to gender and insulin sensitivity/resistance. Adipose cell-size distribution changes in each individual are simulated with a dynamic model and parameters corresponding to lipid turnover and cell growth rates are determined for each subgroup to match the...... relative change of fat mass for each diet composition, respectively. We find that adipose cell-size dynamics are associated with different modulations dependent on gender and insulin resistance. Larger turnover and growth/shrinkage rates in insulin resistant individuals suggest they may be more sensitive...

  20. Method of separating (125I)-L-thyroxine from mixture obtained by radioiodination

    International Nuclear Information System (INIS)

    (125I)-L-thyroxine is separated by gel filtration on a column from the mixture of (125I)-L-thyroxine, (125I)-L-3,5,3'-triiodothyronine and (125I)-. The column is packed with a non-polar gel such as polydextran with particle size 25 to 100 μm. The mixture 1,2-propanediol/distilled water/concentrated (26%) aqueous ammonia solution, or 1,2-propanediol/concentrated (26%) aqueous ammonia solution is used as eluent. The concentration of the eluate containing (125I)-L-thyroxine is adjusted with distilled water such as to establish a 50 vol.% concentration of 1,2-propanediol. (E.S.)

  1. Clinical assessment of a radioimmunoassay for free thyroxine using a modified tracer

    International Nuclear Information System (INIS)

    A radioimmunoassay for measuring free thyroxine in plasma was introduced by Amersham using a I-125-labeled T4 derivative that does not bind significantly to the thyroxine-binding proteins. This RIA was evaluated for its clinical utility in assessing 278 patients with thyroid and nonthyroidal diseases. The precision of the Amerlex free T4 assay was expressed as coefficient of variation. The correlation coefficients (r) of a dialysis method and a free thyroxine index were 0.871 and 0.911, respectively. Free T4 correctly classified 98% euthyroid, 92% hypothyroid, 100% hyperthyroid, 100% euthyroid with elevated TBG, and 87% of phenytoin patients. In addition, 80 patients with acute nonthyroidal illness were studied. Most of these patients have normal to low free T4, very low T3, and elevated rT3. We found this free T4 assay to be precise, easy to perform, and reliable in classifying thyroid status in most patients

  2. Irradiated brown dwarfs

    CERN Document Server

    Casewell, S L; Lawrie, K A; Maxted, P F L; Dobbie, P D; Napiwotzki, R

    2014-01-01

    We have observed the post common envelope binary WD0137-349 in the near infrared $J$, $H$ and $K$ bands and have determined that the photometry varies on the system period (116 min). The amplitude of the variability increases with increasing wavelength, indicating that the brown dwarf in the system is likely being irradiated by its 16500 K white dwarf companion. The effect of the (primarily) UV irradiation on the brown dwarf atmosphere is unknown, but it is possible that stratospheric hazes are formed. It is also possible that the brown dwarf (an L-T transition object) itself is variable due to patchy cloud cover. Both these scenarios are discussed, and suggestions for further study are made.

  3. Fucoidans from brown seaweeds

    DEFF Research Database (Denmark)

    Ale, Marcel Tutor; Meyer, Anne S.

    2013-01-01

    -proliferative effects on cancer cells. Recent work has revealed distinct structural features of fucoidans obtained from different brown seaweed sources. Fucoidans are classically obtained from brown seaweeds by multi-step, hot acid extraction, but the structural and compositional traits, and possibly the bioactivity......Fucoidan or fucoidans cover a family of sulfated fucose-rich polysaccharides, built of a backbone of L-fucose units, and characteristically found in brown seaweeds. Fucoidans have potential therapeutic properties, including anti-inflammatory and anti-coagulant activities, as well as anti......, of the fucoidan polysaccharides are significantly influenced by the extraction parameters. This review discusses the structural features of fucoidans, the significance of different extraction technologies, and reviews enzymatic degradation of fucoidans and the use of fucoidan-modifying enzymes for...

  4. The effect of L-thyroxine treatment on chronic idiopathic urticaria and autoimmune thyroiditis.

    Science.gov (United States)

    Magen, Eli; Mishal, Joseph

    2012-01-01

    Autoimmune thyroiditis (AT) is more prevalent in patients with chronic idiopathic urticaria CIU) than in the general population. Previous small studies without any controlled comparison reported that CIU remits in patients with CIU and AT treated with L-thyroxine. To determine whether l-thyroxine treatment can improve the clinical course of CIU in patients with the co-occurrence of AT and CIU. A total of 749 patients with CIU were retrospectively studied. Clinical and laboratory evaluation and classification of chronic urticaria were performed according to the EAACI/GA(2)LEN/EDF/WAO guidelines. After L-thyroxine treatment for 53 ± 19 days, euthyroidism was restored in all subjects. Urticaria activity score (UAS) was evaluated at baseline and after three and six months. The control group consisted of matched 44 euthyroid subjects with CIU. A total of 44 (5.9%) patients were diagnosed to have hypothyroidism related to AT. Autologous serum skin test (ASST) was found to be positive in 17 (38.6%) of them. There was no statistically significant difference in baseline UAS, between the ASST+ (3.94 ± 1.52) and the ASST- (3.63 ± 1.42; P = 0.27) hypothyroid subjects and the euthyroid CIU controls (3.73 ± 1.74). During the L-thyroxine treatment, a significant reduction of UAS was observed in both hypothyroid ASST+ and ASST- subjects. However, the mean UAS after three and six months of L-thyroxine treatment remained not significantly different from that in control euthyroid subjects with CIU. L-Thyroxine treatment has no effect on the course of CIU in patients with CIU and AT. PMID:22182385

  5. Dyslipidemia in subclinical hypothyroidism and the effect of thyroxine on lipid profile

    Directory of Open Access Journals (Sweden)

    Ajay Asranna

    2012-01-01

    Full Text Available Introduction: Subclinical hypothyroidism (SH has a prevalence between 4% and 10.5% in various studies. The burden of SH in India is expected to increase with increasing iodine sufficiency. Studies have shown conflicting results concerning not only the degree of lipid changes in SH but also the effect of thyroxine substitution therapy. Indian studies on dyslipidemia in SH and the effect of thyroxine on lipid profile are currently lacking. Aims and Objectives: (1 To assess the association of SH and lipid profile. (2 To quantify the effect of thyroxine treatment on lipid profile. Materials and Methods: About 54 patients who were detected to have SH were compared with 56 healthy controls. Thyroid stimulating hormone (TSH, free T3, free T4, anti thyroperoxidase (TPO antibodies, total cholesterol, high density lipoprotein (HDL cholesterol, low density lipoprotein (LDL cholesterol, Very low density lipoprotein (VLDL cholesterol, serum triglycerides were measured in all the patients after an overnight fast. Selected patients were started on thyroxine replacement. Twenty-one patients were followed up after 3 months with a repeat lipid profile. Results: Mean total cholesterol and mean LDL levels were significantly higher in SH compared to controls, but there was no statistically significant difference in the mean HDL, VLDL, and triglyceride levels. There was a significant reduction in mean T. cholesterol, mean LDL, mean VLDL, and mean triglyceride levels after treatment with thyroxine, while there was no significant difference among the mean HDL levels. Conclusion: Dyslipidemia is more common in SH compared to controls. There is a TSH dependent increase in cholesterol, LDL, VLDL, and triglyceride levels. Achieving euthyroid status with thyroxine has a favourable effect on lipid profile.

  6. Free Thyroxine During Early Pregnancy and Risk for Gestational Diabetes

    Science.gov (United States)

    Haddow, James E.; Craig, Wendy Y.; Neveux, Louis M.; Palomaki, Glenn E.; Lambert-Messerlian, Geralyn; Malone, Fergal D.; D’Alton, Mary E.

    2016-01-01

    Several studies have now reported associations between gestational diabetes mellitus (GDM) and low free thyroxine (fT4) during the second and third trimesters, but not in the first trimester. The present study further examines relationships between low fT4, maternal weight, and GDM among women in the FaSTER (First and Second Trimester Evaluation of Risk) trial, in an effort to determine the extent to which thyroid hormones might contribute to causality. The FaSTER cohort includes 9351 singleton, euthyroid women; 272 of these women were subsequently classified as having GDM. Thyrotropin (TSH), fT4, and thyroid antibodies were measured at 11–14 weeks’ gestation (first trimester) and 15–18.9 weeks’ gestation (second trimester). An earlier report of this cohort documented an inverse relationship between fT4 in the second trimester and maternal weight. In the current analysis, women with GDM were significantly older (32 vs. 28 years) and weighed more (75 vs. 64.5 kg). Maternal weight and age (but not TSH) were significantly associated univariately with fT4 (dependent variable), in the order listed. Second trimester fT4 odds ratios (OR) for GDM were 2.06 [95% CI 1.37–3.09] (unadjusted); and 1.89 [95% CI 1.26–2.84] (adjusted). First trimester odds ratios were not significant: OR 1.45 [95%CI 0.97–2.16] (unadjusted) and 1.11 [95% CI 0.74–1.62] (adjusted). The second trimester fT4/GDM relationship thus appeared to strengthen as gestation progressed. In FaSTER, high maternal weight was associated with both low fT4 and a higher GDM rate in the second trimester. Peripheral deiodinase activity is known to increase with high caloric intake (represented by high weight). We speculate that weight-related low fT4 (the metabolically inactive prohormone) is a marker for deiodinase activity, serving as a substrate for conversion of fT4 to free triiodothyronine (fT3), the active hormone responsible for glucose-related metabolic activity. PMID:26910563

  7. A role of active brown adipose tissue in cancer cachexia?

    Directory of Open Access Journals (Sweden)

    Emiel Beijer

    2012-06-01

    Full Text Available Until a few years ago, adult humans were not thought to have brown adipose tissue (BAT. Now, this is a rapidly evolving field of research with perspectives in metabolic syndromes such as obesity and new therapies targeting its bio-energetic pathways. White, brown and socalled brite adipose fat seem to be able to trans-differentiate into each other, emphasizing the dynamic nature of fat tissue for metabolism. Human and animal data in cancer cachexia to date provide some evidence for BAT activation, but its quantitative impact on energy expenditure and weight loss is controversial. Prospective clinical studies can address the potential role of BAT in cancer cachexia using 18F-fluorodeoxyglucose positron emission tomography-computed tomography scanning, with careful consideration of co-factors such as diet, exposure to the cold, physical activity and body mass index, that all seem to act on BAT recruitment and activity.

  8. Enhancement of brown fat thermogenesis using chenodeoxycholic acid in mice

    Czech Academy of Sciences Publication Activity Database

    Teodoro, J.S.; Zouhar, Petr; Flachs, Pavel; Bardová, Kristina; Janovská, Petra; Gomes, A.P.; Duarte, F.V.; Varela, A.T.; Rolo, A.P.; Palmeira, C.M.; Kopecký, Jan

    2014-01-01

    Roč. 38, č. 8 (2014), s. 1027-1034. ISSN 0307-0565 R&D Projects: GA MŠk(CZ) 7E12073; GA ČR(CZ) GA13-00871S Institutional support: RVO:67985823 Keywords : white adipose tissue * uncoupling protein 1 * energy expenditure * bile acids Subject RIV: FB - Endocrinology, Diabetology, Metabolism, Nutrition Impact factor: 5.004, year: 2014

  9. Dietary lipids: less fat or best fat?

    Directory of Open Access Journals (Sweden)

    Chardigny Jean-Michel

    2013-03-01

    Full Text Available Obesity and overweight occurrence is growing around the word. This is often considered as a consequence of high fat diets, and some recommendations encourage ‘‘light’’ diets, including low fat intake. However, most trials with low fat intake do not demonstrate any benefit and could be worse than low carbohydrate diets. The key role of insulin could explain that eating fat do not make body fat. On the other hand, several unbalanced fatty acid intake are reported, i.e. saturated/mononunsaturated fatty acids and w6/w3 polyunsaturated fatty acids. Thus, fat intake could be improved in this respect. Moreover, the molecular and supramolecular structures of fat in food are new challenges to address in order to ameliorate the recommendations for healthy diets.

  10. A New Role for Browning as a Redox and Stress Adaptive Mechanism?

    OpenAIRE

    Jeanson, Yannick; Carrière, Audrey; Casteilla, Louis

    2015-01-01

    The worldwide epidemic of obesity and metabolic disorders is focusing the attention of the scientific community on white adipose tissue (WAT) and its biology. This tissue is characterized not only by its capability to change in size and shape but also by its heterogeneity and versatility. WAT can be converted into brown fat-like tissue according to different physiological and pathophysiological situations. The expression of uncoupling protein-1 in brown-like adipocytes changes their function ...

  11. Both liver-X receptor (LXR) isoforms control energy expenditure by regulating Brown Adipose Tissue activity

    OpenAIRE

    Korach-André, Marion; Archer, Amena; Barros, Rodrigo P.; Parini, Paolo; Gustafsson, Jan-Åke

    2010-01-01

    Brown adipocytes are multilocular lipid storage cells that play a crucial role in nonshivering thermogenesis. Uncoupling protein 1 (UCP1) is a unique feature of brown fat cells that allows heat generation on sympathetic nervous system stimulation. As conventional transcriptional factors that are activated in various signaling pathways, liver-X receptors (LXRs) play important roles in many physiological processes. The role of LXRs in the regulation of energy homeostasis remains unclear, howeve...

  12. FGF21 regulates PGC-1α and browning of white adipose tissues in adaptive thermogenesis

    OpenAIRE

    Fisher, ffolliott M.; Kleiner, Sandra; Douris, Nicholas; Fox, Elliott C.; Mepani, Rina J.; Verdeguer, Francisco; Wu, Jun; Kharitonenkov, Alexei; Flier, Jeffrey S.; Maratos-Flier, Eleftheria; Spiegelman, Bruce M.

    2012-01-01

    Brown adipose tissue (BAT) can protect against hypothermia and obesity by using lipids to produce heat. In this study, Spiegelman and colleagues studied FGF21 control of thermogenesis in mice. The authors used gain- and loss-of-function experiments to demonstrate that FGF21 induces a brown fat phenotype in white adipose tissues. In addition, they found that FGF21 is required for the adaptive thermogenic response of mice by increasing PGC-1α protein levels, independent of its transcription. Th...

  13. Regulation of brown adipocyte metabolism by myostatin/follistatin signaling

    Directory of Open Access Journals (Sweden)

    Rajan eSingh

    2014-10-01

    Full Text Available Obesity develops from perturbations of cellular bioenergetics, when energy uptake exceeds energy expenditure, and represents a major risk factor for the development of type 2 diabetes, dyslipidemia, cardiovascular disease, cancer, and other conditions. Brown adipose tissue (BAT has long been known to dissipate energy as heat and contribute to energy expenditure, but its presence and physiological role in adult human physiology has been questioned for years. Recent demonstrations of metabolically active brown fat depots in adult humans have revolutionized current therapeutic approaches for obesity-related diseases. The balance between white adipose tissue (WAT and BAT affects the systemic energy balance and is widely believed to be the key determinant in the development of obesity and related metabolic diseases. Members of the transforming growth factor-beta (TGF-β superfamily play an important role in regulating overall energy homeostasis by modulation of brown adipocyte characteristics. Inactivation of TGF-β/Smad3/myostatin (Mst signaling promotes browning of white adipocytes, increases mitochondrial biogenesis and protects mice from diet-induced obesity, suggesting the need for development of a novel class of TGF-β/Mst antagonists for the treatment of obesity and related metabolic diseases. We recently described an important role of follistatin (Fst, a soluble glycoprotein that is known to bind and antagonize Mst actions, during brown fat differentiation and the regulation of cellular metabolism. Here we highlight various investigations performed using different in vitro and in vivo models to support the contention that targeting TGF-β/Mst signaling enhances brown adipocyte functions and regulates energy balance, reducing insulin resistance and curbing the development of obesity and diabetes.

  14. Cold–inducible Zfp516 Activates UCP1 Transcription to Promote Browning of White Fat and Development of Brown Fat

    OpenAIRE

    Dempersmier, Jon; Sambeat, Audrey; Gulyaeva, Olga; Paul, Sarah M.; Hudak, Carolyn S. S.; Raposo, Helena F.; Kwan, Hiu-Yee; Kang, Chulho; Wong, Roger H. F.; Sul, Hei Sook

    2015-01-01

    Uncoupling protein 1 (UCP1) mediates non-shivering thermogenesis and, upon cold exposure, is induced in BAT and subcutaneous white adipose tissue (iWAT). Here, by high-throughput screening using the UCP1 promoter, we identify Zfp516 as a novel transcriptional activator of UCP1 as well as PGC1α thereby promoting a BAT program. Zfp516 itself is induced by cold and sympathetic stimulation through the cAMP-CREB/ATF2 pathway. Zfp516 directly binds to the proximal region of the UCP1 promoter, not t...

  15. Emulsion Mapping in Pork Meat Emulsion Systems with Various Lipid Types and Brown Rice Fiber.

    Science.gov (United States)

    Choi, Yun-Sang; Kim, Young-Boong; Kim, Hyun-Wook; Hwang, Ko-Eun; Song, Dong-Heon; Jeong, Tae-Jun; Park, Jinhee; Kim, Cheon-Jei

    2015-01-01

    This study was conducted to evaluate emulsion mapping between emulsion stability and cooking yields, apparent viscosity, and hardness of reduced-fat pork emulsion systems. The reduced-fat emulsion systems were supplemented with different lipid types and brown rice bran fiber (BRF) concentrations. Compared to the control with 30% back fat, lower emulsion stability and higher cooking yield of meat emulsion systems were observed in T1 (30% back fat+1% BRF), T2 (30% back fat+2% BRF), T3 (30% back fat+3% BRF), T4 (30% back fat+6% BRF), and T15 (10% back fat+10% canola oil+2% BRF). Lower emulsion stability and higher apparent viscosity were observed in T1, T2, T3, T4, and T8 (20% back fat+3% BRF) compared to the control. Lower emulsion stability and higher hardness was detected in all treatments compared with the control, except T5 (20% back fat), T10 (10% back fat+10% canola oil+2% BRF), T11 (10% back fat+10% olive oil+2% BRF), T12 (10% back fat+10% grape seed oil+2% BRF), and T13 (10% back fat+10% soybean oil+2% BRF). This approach has been found particularly useful for highlighting differences among the emulsified properties in emulsion meat products. Thus, the results obtained with emulsion mapping are useful in making emulsified meat products of desired quality characteristics, partially replacing pork back fat with a mix of 10% back fat, 10% canola oil and 2% BRF was most similar to the control with 30% pork back fat. PMID:26761836

  16. Impact of adjusting for the reciprocal relationship between maternal weight and free thyroxine during early pregnancy.

    LENUS (Irish Health Repository)

    Haddow, James E

    2013-02-01

    Among euthyroid pregnant women in a large clinical trial, free thyroxine (FT4) measurements below the 2.5th centile were associated with a 17 lb higher weight (2.9 kg\\/m(2)) than in the overall study population. We explore this relationship further.

  17. Preparation of standards of triiodothyronine, thyroxine and thyrotropin; Prepracion de estandares de triyodotironina, tiroxina y tirotrofina

    Energy Technology Data Exchange (ETDEWEB)

    Lavalley E, C.; Delgado S, B.; Ruiz J, A.; Zambrano A, F

    1991-10-15

    The standards preparation requires of certain basic principles, some of which are described in this work, which was made with the purpose of establishing the most appropriate conditions for the preparation of standards of triiodothyronine, thyroxine and thyrotropin to be used in radioimmunoanalysis essays. The diverse standards show a balanced displacement, that which is observed in the graphs presented in this work. (Author)

  18. Triclosan Decreases Rat Thyroxine: Mode-of-Action, Developmental Susceptibility and Human Relevance

    Science.gov (United States)

    Triclosan (TCS) decreases serum thyroxine (T4) in the rat. In vivo and in vitro approaches were used to address three uncertainties: by what mode-of-action (MOA) does TCS decrease T4; does TCS decrease T4 developmentally; and, are effects observed in rats relevant to humans? To t...

  19. Retinoblastoma protein functions as a molecular switch determining white versus brown adipocyte differentiation

    DEFF Research Database (Denmark)

    Hansen, Jacob B; Jørgensen, Claus; Petersen, Rasmus K;

    2004-01-01

    Adipocyte precursor cells give raise to two major cell populations with different physiological roles: white and brown adipocytes. Here we demonstrate that the retinoblastoma protein (pRB) regulates white vs. brown adipocyte differentiation. Functional inactivation of pRB in wild-type mouse embryo...... fibroblasts (MEFs) and white preadipocytes by expression of simian virus 40 large T antigen results in the expression of the brown fat-specific uncoupling protein 1 (UCP-1) in the adipose state. Retinoblastoma gene-deficient (Rb-/-) MEFs and stem cells, but not the corresponding wild-type cells, differentiate...

  20. Comparative integromics on FAT1, FAT2, FAT3 and FAT4.

    Science.gov (United States)

    Katoh, Yuriko; Katoh, Masaru

    2006-09-01

    WNT5A, WNT5B, WNT11, FZD3, FZD6, VANGL1, VANGL2, DVL1, DVL2, DVL3, PRICKLE1, PRICKLE2, ANKRD6, NKD1, NKD2, DAAM1, DAAM2, CELSR1, CELSR2, CELSR3, ROR1 and ROR2 are planar cell polarity (PCP) signaling molecules implicated in the regulation of cellular polarity, convergent extension, and invasion. FAT1, FAT2, FAT3 and FAT4 are Cadherin superfamily members homologous to Drosophila Fat, functioning as a positive regulator of PCP in the Drosophila wing. Complete coding sequence (CDS) for human FAT1 (NM_005245.3) and FAT2 (NM_001447.1) are available, while artificial CDS for human FAT3 (XM_926199 and XM_936538) and partial CDS for FAT4 (NM_024582.2). Here, complete CDS of human FAT3 and FAT4 were determined by using bioinformatics and human intelligence (Humint). FAT3 gene, consisting of 26 exons, encoded a 4557-aa protein with extracellular 33 Cadherin repeats, one Laminin G (LamG) domain and two EGF domains. FAT4 gene encoded a 4924-aa protein with extracellular 34 Cadherin repeats, two LamG domains and three EGF domains. Cytoplasmic VCSVxPxLP and SDYxS motifs were identified as novel motifs conserved among FAT1, FAT2 and FAT3 orthologs. Domain architecture comparison and phylogenetic analysis revealed that FAT1, FAT2 and FAR3 were divergent from FAT4. FAT1-MTNR1A locus at 4q35.2 and FAT3-MTNR1B locus at 11q14.3-q21 were paralogous regions within the human genome. FAT1 mRNA was expressed in embryonic stem (ES) cells, neural tissues, gastric cancer, pancreatic cancer, colorectal cancer, breast cancer, lung cancer and brain tumors. FAT2 mRNA was expressed in infant brain, cerebellum, gastric cancer, pancreatic cancer, ovarian cancer, esophageal cancer, skin squamous cell carcinoma, head and neck cancer. FAT3 mRNA was expressed in ES cells, primitive neuroectoderm, fetal brain, infant brain, adult neural tissues and prostate. FAT4 mRNA was expressed in fetal brain, infant brain, brain tumor and colorectal cancer. FAT family members were revealed to be targets of systems

  1. Wide tissue distribution of axolotl class II molecules occurs independently of thyroxin.

    Science.gov (United States)

    Völk, H; Charlemagne, J; Tournefier, A; Ferrone, S; Jost, R; Parisot, R; Kaufman, J

    1998-04-01

    Unlike most salamanders, the Mexican axolotl (Ambystoma mexicanum) fails to produce enough thyroxin to undergo anatomical metamorphosis, although a "cryptic metamorphosis" involving a change from fetal to adult hemoglobins has been described. To understand to what extent the development of the axolotl hemopoietic system is linked to anatomical metamorphosis, we examined the appearance and thyroxin dependence of class II molecules on thymus, blood, and spleen cells, using both flow cytometry and biosynthetic labeling followed by immunoprecipitation. Class II molecules are present on B cells as early as 7 weeks after hatching, the first time analyzed. At this time, most thymocytes, all T cells, and all erythrocytes lack class II molecules, but first thymocytes at 17 weeks, then T cells at 22 weeks, and finally erythrocytes at 26-27 weeks virtually all bear class II molecules. Class II molecules and adult hemoglobin appear at roughly the same time in erythrocytes. These data are most easily explained by populations of class II-negative cells being replaced by populations of class II-positive cells, and they show that the hemopoietic system matures at a variety of times unrelated to the increase of thyroxin that drives anatomical metamorphosis. We found that administration of thyroxin during axolotl ontogeny does not accelerate or otherwise affect the acquisition of class II molecules, nor does administration of drugs that inhibit thyroxin (sodium perchlorate, thiourea, methimazole, and 1-methyl imidazole) retard or abolish this acquisition, suggesting that the programs for anatomical metamorphosis and some aspects of hemopoietic development are entirely separate. PMID:9510551

  2. Genetic Analysis of Brown Adipose Tissue, Obesity and Growth in Mice

    OpenAIRE

    Saxton, A. M.; Eisen, E. J.

    1984-01-01

    The hypothesis developed from single-gene mutant obese rodents that brown adipose tissue (BAT), through its thermogenic ability, is an important factor in the development of obesity, was tested in a randombred population of mice in which degree of adiposity is polygenically determined. Additive direct genetic parameters for measures of body size, lean, fatness and BAT at 6 wk of age were estimated under control and high-fat postweaning dietary regimens. Heritabilities were generally similar f...

  3. Estrogens increase expression of bone morphogenetic protein 8b in brown adipose tissue of mice

    OpenAIRE

    Grefhorst, Aldo; van den Beukel, Johanna C; van Houten, E Leonie AF; Steenbergen, Jacobie; Visser, Jenny A.; Themmen, Axel PN

    2015-01-01

    Background In mammals, white adipose tissue (WAT) stores fat and brown adipose tissue (BAT) dissipates fat to produce heat. Several studies showed that females have more active BAT. Members of the bone morphogenetic protein (BMP) and fibroblast growth factor (FGF) families are expressed in BAT and are involved in BAT activity. We hypothesized that differential expression of BMPs and FGFs might contribute to sex differences in BAT activity. Methods We investigated the expression of BMPs and FG...

  4. Between brown and white: novel aspects of adipocyte differentiation.

    Science.gov (United States)

    Cinti, Saverio

    2011-03-01

    In all mammals including humans, most white and brown adipocytes are found together in visceral and subcutaneous depots (adipose organ) despite the well known difference in their function, respectively of storing energy and producing heat. A growing body of evidence suggests that the reason for such anatomical arrangement is their plasticity, which under appropriate stimulation allows direct conversion of one cell type into the other. In conditions of chronic cold exposure white-to-brown conversion meets the need for thermogenesis, whereas an obesogenic diet induces brown-to-white conversion to meet the need for storing energy. White-to-brown transdifferentiation is of medical interest, because the brown phenotype of the adipose organ is associated to obesity resistance, and drugs inducing this phenotype curb murine obesity and related disorders. Type 2 diabetes is the most common disorder associated to visceral obesity. Macrophages infiltrating the adipose organ are responsible for the low-grade chronic inflammation related to the removal of dead adipocytes, which leads to insulin resistance and T2 diabetes. Adipocyte death is closely related to their growth up to the critical death size. The critical death size of visceral adipocytes is smaller than that of subcutaneous adipocytes, likely accounting for the greater morbidity related to visceral fat. PMID:21254898

  5. Breaking BAT: can browning create a better white?

    Science.gov (United States)

    Warner, Amy; Mittag, Jens

    2016-01-01

    Obesity and its comorbidities are a growing problem worldwide. In consequence, several new strategies have been proposed to promote weight loss and improve insulin sensitivity. Recently, it has been demonstrated that certain populations of white adipocytes can be 'browned', i.e., recruited to a more brown-like adipocyte, capable of thermogenesis through increased expression of uncoupling protein 1. The list of browning agents that induce these so-called beige adipocytes is growing constantly. However, the underlying mechanisms are often poorly understood, with the possibility that some of these agents cause browning as a secondary effect. Moreover, it remains unclear whether beige adipocytes can contribute sufficiently to affect whole-body energy expenditure in a functionally significant manner. This review presents an overview of the different molecular pathways leading to the induction of beige fat, including direct stimulation and indirect actions on the CNS or the immune system. We discuss the available evidence on the capacity of beige adipocytes to influence whole-body energy expenditure in rodents, and lastly outline the potential problems of translating browning capacity into the potential treatment of human metabolic diseases. PMID:26450134

  6. Increased Mitochondrial Activity in BMP7-Treated Brown Adipocytes, Due to Increased CPT1- and CD36-Mediated Fatty Acid Uptake

    OpenAIRE

    Townsend, Kristy L.; An, Ding; Lynes, Matthew D.; Huang, Tian Lian; Zhang, Hongbin; Goodyear, Laurie J.; Tseng, Yu-Hua

    2013-01-01

    Aims: Brown adipose tissue dissipates chemical energy in the form of heat and regulates triglyceride and glucose metabolism in the body. Factors that regulate fatty acid uptake and oxidation in brown adipocytes have not yet been fully elucidated. Bone morphogenetic protein 7 (BMP7) is a growth factor capable of inducing brown fat mitochondrial biogenesis during differentiation from adipocyte progenitors. Administration of BMP7 to mice also results in increased energy expenditure. To determine...

  7. Apelin Enhances Brown Adipogenesis and Browning of White Adipocytes.

    Science.gov (United States)

    Than, Aung; He, Hui Ling; Chua, Si Hui; Xu, Dan; Sun, Lei; Leow, Melvin Khee-Shing; Chen, Peng

    2015-06-01

    Brown adipose tissue expends energy in the form of heat via the mitochondrial uncoupling protein UCP1. Recent studies showed that brown adipose tissue is present in adult humans and may be exploited for its anti-obesity and anti-diabetes actions. Apelin is an adipocyte-derived hormone that plays important roles in energy metabolism. Here, we report that apelin-APJ signaling promotes brown adipocyte differentiation by increasing the expressions of brown adipogenic and thermogenic transcriptional factors via the PI3K/Akt and AMPK signaling pathways. It is also found that apelin relieves the TNFα inhibition on brown adipogenesis. In addition, apelin increases the basal activity of brown adipocytes, as evidenced by the increased PGC1α and UCP1 expressions, mitochondrial biogenesis, and oxygen consumption. Finally, we provide both in vitro and in vivo evidence that apelin is able to increase the brown-like characteristics in white adipocytes. This study, for the first time, reveals the brown adipogenic and browning effects of apelin and suggests a potential therapeutic route to combat obesity and related metabolic disorders. PMID:25931124

  8. Trans Fat Now Listed With Saturated Fat and Cholesterol

    Science.gov (United States)

    ... Trans Fat Now Listed With Saturated Fat and Cholesterol Share Tweet Linkedin Pin it More sharing options ... I Do About Saturated Fat, Trans Fat, and Cholesterol? When comparing foods, look at the Nutrition Facts ...

  9. Lipocytes (fat cells) (image)

    Science.gov (United States)

    ... to energy output, there is no expansion of fat cells (lipocytes) to accommodate excess. It is only when more calories are taken in than used that the extra fat is stored in the lipocytes and the person ...

  10. Facts about trans fats

    Science.gov (United States)

    ... of servings you eat in one sitting. Many fast food restaurants use solid oils with trans fat for ... frozen yogurt, milk shakes, and pudding Snack foods Fast food Solid fats, such as shortening and margarine Nondairy ...

  11. Weighing in on Dietary Fats

    Science.gov (United States)

    ... wrong” kinds of fats can trigger additional health hazards. “Some fats are better for our bodies than ... ingredients. “Low-fat and fat-free yogurt and milk still contain the important proteins and minerals found ...

  12. Thyrotoxic periodic paralysis due to excessive L-thyroxine replacement in a Caucasian man.

    LENUS (Irish Health Repository)

    Hannon, M J

    2009-09-01

    Thyrotoxic periodic paralysis is a potentially fatal complication of hyperthyroidism, more common in Asian races, which is defined by a massive intracellular flux of potassium. This leads to profound hypokalaemia and muscle paralysis. Although the paralysis is temporary, it may be lethal if not diagnosed and treated rapidly, as profound hypokalaemia may induce respiratory muscle paralysis or cardiac arrest. The condition is often misdiagnosed in the west due to its comparative rarity in Caucasians; however it is now increasingly described in Caucasians and is also being seen with increasing frequency in western hospitals due to increasing immigration and population mobility. Here we describe the case of a patient with panhypopituitarism due to a craniopharyngioma, who developed thyrotoxic periodic paralysis due to excessive L-thyroxine replacement. This disorder has been described in Asian subjects but, to our knowledge, thyrotoxic periodic paralysis secondary to excessive L-thyroxine replacement has never been described in Caucasians.

  13. Settlement and metamorphosis of Styela canopus Savigny larvae in response to some neurotransmitters and thyroxin

    Institute of Scientific and Technical Information of China (English)

    FENG Danqing; HUANG Ying; KE Caihuan; ZHOU Shiqiang; LI Shaojing

    2006-01-01

    The larvae of ascidian Styela canopus Savigny were treated with epinephrine, norepinephrine, L-DOPA, GABA and thyroxin to test the ability of these compounds to induce or inhibit larval settlement and metamorphosis. The results showed that epinephrine,norepinephrine and L-DOPA at the concentration of 1 μ mol/dm3 induced larval settlement and metamorphosis in S. canopus, with short exposure ( 1 h) to 1 μmoL/dm3 of L-DOPA inducing rapid settlement. In contrast, GABA at the concentrations of 0.1 ~100.0 μmol/dm3 significantly inhibited the settlement and metamorphosis of S. canopus larvae. In addition, thyroxin at 1 ~ 50μg/dm3 had no effect on larval settlement and metamorphosis in S. canopus. These results suggest the importance of neurotransmitters in the settlement and metamorphosis of S. canopus larvae.

  14. Metabolic responses to adrenaline and muscle glycogen content in dogs treated with thyroxine.

    Science.gov (United States)

    Brzezińska, Z; Kaciuba-Uściłko, H

    1978-01-01

    Lipolytic, hyperglycaemic and lactacidaemic responses to 1h adrenaline infusion (0.1 microgram/kg/min) were compared in resting dogs before (control) and after prolonged thyroxine (T4) treatment. Besides, the effect of 2-week thyroxine administration on muscle glycogen content, and its changes following adrenaline infusion were examined. Prolonged T4-treatment of dogs resulted in considerable alterations of the metabolic actions of adrenaline. A marked difference between the control and T4-treated dogs was also found in the muscle glycogen content, which was significantly lower in the latter. Both in the control and T4-injected dogs adrenaline infusion caused similar depletion of the muscle glycogen store. However, in all the control animals examined supercompensation of muscle glycogen was noted 1 h following termination of adrenaline infusion, whereas T4-treated dogs were unable of incurring any significant muscle glycogen deposition. PMID:742367

  15. Thyroxine secretion rate during growth in different types of poultry birds

    International Nuclear Information System (INIS)

    Thyroid activity in pro- and post-pubertal as well as mature poultry birds of egg type i.e. White Leghorn (WLH); dual-purpose i.e. Rhode Island Red (RIR) and meat type i.e. Broiler strain was estimated by determining the thyroxine secretion rate (TSR) using 131I as a radiotracer at 4 weeks, 14 weeks and 24 weeks of age. The study has revealed that the birds have higher thyroxine secretion rates during pre-pubertal as compared to the post-pubertal period as well as the period around the age of maturity. The birds of Broiler strain have higher TSR as compared to both the pure egg-type and the dual-purpose breeds. (author)

  16. Thermal stability of synthetic thyroid hormone l-thyroxine and l-thyroxine sodium salt hydrate both pure and in pharmaceutical formulations.

    Science.gov (United States)

    Ledeţi, Ionuţ; Ledeţi, Adriana; Vlase, Gabriela; Vlase, Titus; Matusz, Petru; Bercean, Vasile; Şuta, Lenuţa-Maria; Piciu, Doina

    2016-06-01

    In this paper, the thermal stability of pure l-thyroxine (THY) and l-thyroxine sodium salt hydrate (THYSS) vs. two pharmaceutical solid formulations commercialized on both Romanian and European market (with a content of 100μg, respectively 200μg THYSS per tablet) were investigated. In order to determine whether the presence of excipients affects the thermal stability of the active pharmaceutical ingredient (API), the preliminary study of thermal stability in air atmosphere was completed with an in-depth solid-state kinetic study. By kinetic analysis, the non-isothermal degradation of the selected active pharmaceutical ingredients vs. the solid formulation with strength of 200μg THYSS per tablet was investigated. Isoconversional methods (Kissinger-Akahira-Sunose, Flynn-Wall-Ozawa and Friedman) were employed for the estimation of activation energies values, at five different heating rates, β=5, 7, 10, 12 and 15°Cmin(-1). Also, a fourth method was applied in the processing of data, namely NPK, allowing an objective separation in the physical and chemical processes that contribute to the thermal degradation of the selected compounds. A discussion of thermal stability from the kinetic point of view is also presented. PMID:26999320

  17. Decreased serum triiodothyronine in starving rats is due primarily to diminished thyroidal secretion of thyroxine.

    OpenAIRE

    Kinlaw, W B; Schwartz, H L; Oppenheimer, J. H.

    1985-01-01

    Although thyroxine (T4) 5'-deiodinase activity is diminished in liver homogenates of starved rats, no information is available regarding the effect of starvation on net T4 to triiodothyronine (T3) conversion in the intact rat. It appeared important to clarify this relationship since rat liver homogenates are widely used as a model for the study of the factors responsible for reduced circulating T3 in chronically ill and calorically deprived patients. In contrast to the expected selective decr...

  18. Timing of thyroxine dose adjustment in hypothyroid patients: when are TSH levels stable?

    OpenAIRE

    Kohler, S.; Senn, O; Saleh, L.; Wass, J. A. H.; Schmid, C H

    2014-01-01

    BACKGROUND: Serum TSH is the target hormone by which adequate thyroid hormone supply can easily be monitored in patients with primary hypothyroidism. It is however controversial when TSH should be measured before thyroxine dose adjustments are made: 4 to 8 weeks are recommended. We looked at the time required to reach stable TSH levels in hypothyroid patients. METHODS: We studied patients with newly diagnosed hypothyroidism (TSH >10 mU/l and fT4

  19. Thyroxine modifies the effects of growth hormone in Ames dwarf mice

    OpenAIRE

    Do, Andrew; Menon, Vinal; Zhi, Xu; Gesing, Adam; Wiesenborn, Denise S.; Spong, Adam; Sun, Liou; Bartke, Andrzej; Masternak, Michal M.

    2015-01-01

    Ames dwarf (df/df) mice lack growth hormone (GH), thyroid stimulating hormone and prolactin. Treatment of juvenile df/df mice with GH alone stimulates somatic growth, reduces insulin sensitivity and shortens lifespan. Early‐life treatment with thyroxine (T4) alone produces modest growth stimulation but does not affect longevity. In this study, we examined the effects of treatment of juvenile Ames dwarf mice with a combination of GH + T4 and compared them to the effects of GH alone. Treatment ...

  20. LIPID PROFILE IN OBESE HYPOTHYROID WOMEN RECEIVING THYROXINE – A CROSS SECTIONAL STUDY

    OpenAIRE

    Rekha

    2016-01-01

    INTRODUCTION We evaluated serum lipids in obese hypothyroid women receiving L-thyroxine hormone. METHODS A total of 55 obese hypothyroid women receiving levothyroxine treatment, between 20-55 years were included. Blood samples were assessed for thyroid function markers T3, T4, TSH, and serum lipids total cholesterol (TC) and triglycerides (TG) and Low density lipoprotein (LDL). RESULTS TSH level was significantly increased and T3, T4 concentrations were s...

  1. Cardiogenic shock in a patient with hypothyroid myopathy responsive only to thyroxin replacement: a case report

    OpenAIRE

    Dharmasena, Sanath; Burzyantseva, Olga; Jayawardana, Suriya; Rupanagudy, Vijay A; Pathmanathan, Krishnan

    2010-01-01

    The effect of hypothyroidism on the cardiovascular system has been well documented. Cardiac dysfunction due to hypothyroidism manifests as both systolic and diastolic dysfunction of the heart leading to cardiac arrhythmia and congestive heart failure. Its presentation in the form of refractory hypotension is rare. We describe a 52 year old man on whom Hypothyroid Cardiomyopathy manifested as cardiogenic shock responsive only to thyroxin replacement.

  2. Radioimmunoassay detection of levels of triiodothyronine and thyroxine in Mangalarga Marchador equine

    International Nuclear Information System (INIS)

    Serum levels of triiodothyronine (T3) and thyroxine (T4) were determined in equine of Mangalarga Marchador breed through radioimmunoassay. Forty-two animals (17 males and 25 females), with age ranging from two to eighteen years, were utilized. The values recorded for males and females were, respectively: 101.68 ± 23.44 and 71.14 ± 18.82 ng/d l of T3 (P4 (P<0.05). (author). 10 refs, 1 tab

  3. Effects of thyroxine on L-cysteine desulfuration in mouse liver.

    OpenAIRE

    Wróbel M; Ubuka T; Yao WB; Abe T

    2000-01-01

    The effect of exogenous thyroxine (T4) administration on the activity of rhodanese, cystathionase, and 3-mercaptopyruvate sulfurtransferase (MPST) in the mitochondrial and cytosolic fractions of mouse liver was investigated. Three groups of mice were treated for 6 consecutive days with subcutaneous injections of T4 (50 micrograms, 100 micrograms, and 250 micrograms per 100 g of body wt, respectively). The other 3 groups were given 100 micrograms of T4 per 100 g of body wt for 1, 2, or 3 days....

  4. Prenatal Thyroxine Treatment Disparately Affects Peripheral and Amygdala Thyroid Hormone Levels

    OpenAIRE

    Shukla, Pradeep K.; Sittig, Laura J.; Andrus, Brian M; Schaffer, Daniel J.; Batra, Kanchi K.; Redei, Eva E.

    2009-01-01

    A prenatal hypothyroid state is associated with behavioral abnormalities in adulthood. Wistar–Kyoto (WKY) rats exhibit hypothyroidism and increased depressive and anxiety-like behaviors. Thus, the WKY could illuminate the mechanisms by which the reversal of developmental hypothyroidism in humans and animals results in adult behavioral improvement. We examined the outcome of maternal thyroxine (T4) treatment on thyroid hormone-regulated functions and adult behavior of the WKY offspring. Pregna...

  5. Thyroxin and progesterone concentrations in pregnant, nonpregnant bitches, and bitches during abortion.

    Science.gov (United States)

    Thuróczy, Julianna; Müller, Linda; Kollár, Eszter; Balogh, Lajos

    2016-04-01

    Serum progesterone and thyroxin concentrations were measured weekly until 61 to 62 days after ovulation in 24 pregnant bitches and in the control group of nine nonpregnant bitches in the luteal phase. Fourteen of the 24 dogs had a normal pregnancy and parturition. Ten of the 24 dogs showed mucinous or colored vaginal discharge, decreased appetite, or lethargy. These initial signs of abortion or fetal resorption were noted during the fourth week of pregnancy, and the process occurred over the next 2 weeks. Progesterone and thyroxin concentrations were measured by quantitative ELISAs validated to dog serum. The serum progesterone concentrations of the group going through abortions differed significantly from the third week until the end of the eighth week. The mean serum thyroxin concentrations of healthy pregnant and nonpregnant groups significantly exceeded the reference range (20-45 nmol/L). The serum thyroxin concentrations in the abortion group were between 16.15 ± 3.17 and 40.78 ± 8.97 nmol/L. The values in this group were significantly different from the other two groups at the third week of the luteal phase. Clinical signs of abortion or fetus resorption manifested in midpregnancy. The clinical signs of abortion coincided in each case with a low serum progesterone concentration (<10 ng/mL). This phenomenon indicated, in contrast with other studies, that the decrease of serum progesterone below 10 ng/mL at the fourth week of pregnancy may signal impending abortion. In the second half of pregnancy, the thyroid gland was not able to respond adequately to the elevated requirement in thyroid hormone, although in other periods of the ovarian cycle, there were no clinical signs of hypothyroidism. PMID:26733120

  6. Lack of TRPV2 impairs thermogenesis in mouse brown adipose tissue.

    Science.gov (United States)

    Sun, Wuping; Uchida, Kunitoshi; Suzuki, Yoshiro; Zhou, Yiming; Kim, Minji; Takayama, Yasunori; Takahashi, Nobuyuki; Goto, Tsuyoshi; Wakabayashi, Shigeo; Kawada, Teruo; Iwata, Yuko; Tominaga, Makoto

    2016-03-01

    Brown adipose tissue (BAT), a major site for mammalian non-shivering thermogenesis, could be a target for prevention and treatment of human obesity. Transient receptor potential vanilloid 2 (TRPV2), a Ca(2+)-permeable non-selective cation channel, plays vital roles in the regulation of various cellular functions. Here, we show that TRPV2 is expressed in brown adipocytes and that mRNA levels of thermogenic genes are reduced in both cultured brown adipocytes and BAT from TRPV2 knockout (TRPV2KO) mice. The induction of thermogenic genes in response to β-adrenergic receptor stimulation is also decreased in TRPV2KO brown adipocytes and suppressed by reduced intracellular Ca(2+) concentrations in wild-type brown adipocytes. In addition, TRPV2KO mice have more white adipose tissue and larger brown adipocytes and show cold intolerance, and lower BAT temperature increases in response to β-adrenergic receptor stimulation. Furthermore, TRPV2KO mice have increased body weight and fat upon high-fat-diet treatment. Based on these findings, we conclude that TRPV2 has a role in BAT thermogenesis and could be a target for human obesity therapy. PMID:26882545

  7. Does thyroxine suppression therapy help to rationalize surgery in benign euthyroid nodules?

    International Nuclear Information System (INIS)

    Nodular thyroid disease is a common endocrine problem. Most thyroid nodules are benign hyperplastic lesions, but 5-20% may be a true neoplasm. It is important to differentiate a benign from a malignant nodule early as the approach to treatment in the two is radically different. Early institution of medical management in a benign nodule may obviate the need for surgery. Purpose of the Study: The present work aims to study the efficacy of thyroxine suppression in the management of benign thyroid nodules. Materials and Methods: A prospective study on patients presenting with thyroid nodule was undertaken. The diagnostic work-up included a clinical evaluation, thyroid function tests, thyroid scintigraphy and fine needle aspiration cytology. Based on the investigations, patients were segregated in Group A (toxic nodular goiter), Group B (benign euthyroid nodule) and Group C (malignant nodule). Group A patients were managed with antithyroid drugs and radioiodine and Group C patients were managed surgically. Group B patients were put on thyroxine suppression. Patients who failed to show reduction in size of the nodule at 18 months were treated surgically. Conclusion: The response rate of benign euthyroid nodule to thyroxine suppression was 76% in the present study. (author)

  8. Serum PBDE levels in exposed rats in relation to effects on thyroxine homeostasis

    Energy Technology Data Exchange (ETDEWEB)

    Darnerud, P.O.; Aune, M.; Larsson, L.; Hallgren, S. [National Food Administration, Uppsala (Sweden)

    2004-09-15

    Brominated flame retardants (BFRs) is a group of environmental chemicals for which lately both interest and knowledge have increased considerably. Among the BFRs, the polybrominated diphenyl ethers (PBDEs) have attained special interest. Much data on environmental and human levels have been presented and several toxicological reviews are now published. Among interesting results is the difference in human PBDE levels that seem to exist between U.S.A. and Europe, results that suggest differences in exposure but without being able to pin-point the exact sources. In experimental studies PBDEs alter serum thyroxin levels, an effect seen both in rats and in mice. The mechanism(s) are still not completely clarified, but are thought to include alterations in serum transport, induced enzymatic degradation and possibly also direct effects on the thyroid gland. As perinatal alterations in thyroid homeostasis could affect brain development, early effects on thyroid hormones may be of special concern. Indeed, PBDEs have been shown to affect behaviour and learning in mice, when given neonatally. The aim of the present study was to relate the serum levels of PBDEs in rats to effects of these compounds on thyroxine homeostasis in these animals. Specifically, the relation between serum PBDE levels and effects on serum thyroxine levels was investigated, after two weeks of daily oral exposure. The result may have consequences for the future risk assessment activities on PBDE and specifically in finding the critical serum PBDE concentration at which the effect on thyroid hormone levels begin to occur.

  9. Method for the determination of a new indicator proportional to the plasma concentration of free thyroxine

    International Nuclear Information System (INIS)

    A novel method for the estimation of free thyroxine (T4) in serum is described. Partially heat-denatured serum is mixed with 125I-labelled T4 bound to thyroxine-binding globulin (TBG) on a Sephadex column. After a period of equilibration, the column is eluted with buffer and the residual radioactivity on the column measured. This represents the fraction of 125I-labelled T4 freed from TBG and can be related to the concentration of free T4 in the serum, being expressed as ''proportional free thyroxine'' (PFT4) in μg per 100 ml. In studies of the method, a coefficient of variation of 4.52% in the results was found. The mean PFT4 value in 124 normal subjects was 7.26 +- 1.25 μg per 100 ml. Values below 4.8 μg per 100 ml were considered indicative of hypothyroidism and those above 9.8 μg per 100 ml indicative of hyperthyroidism, in good agreement with clinical findings. The coefficient of correlation between the results and results obtained by the AMES ''Tetralute'' method was 0.911. The mean PFT4 value in 37 pregnant subjects was 12.2 +- 2.1 μg per 100 ml

  10. Tune Your Brown Clustering, Please

    DEFF Research Database (Denmark)

    Derczynski, Leon; Chester, Sean; Bøgh, Kenneth Sejdenfaden

    2015-01-01

    Brown clustering, an unsupervised hierarchical clustering technique based on ngram mutual information, has proven useful in many NLP applications. However, most uses of Brown clustering employ the same default configuration; the appropriateness of this configuration has gone predominantly...... unexplored. Accordingly, we present information for practitioners on the behaviour of Brown clustering in order to assist hyper-parametre tuning, in the form of a theoretical model of Brown clustering utility. This model is then evaluated empirically in two sequence labelling tasks over two text types. We...... explore the dynamic between the input corpus size, chosen number of classes, and quality of the resulting clusters, which has an impact for any approach using Brown clustering. In every scenario that we examine, our results reveal that the values most commonly used for the clustering are sub-optimal....

  11. Effect of overexpression of uncoupling protein 1 on brown adipose tissue in aP2-Ucp mice

    International Nuclear Information System (INIS)

    The aim of the present study was assess the function of mitochondria in brown fat of the transgenic animals in order to explain the functional involution of brown adipose tissue (BAT). This study was based on measurements of transmembrane electrochemical potential (Δψ) and estimation of [3H]GDP binding to isolated brown fat mitochondria, as well as on immunochemical analysis of trans-gene expression. Fluorescent cationic dye Rhodamine 123 was used to follow the changes in Δψ of isolated brown fat mitochondria. The fluorescence is quenched as the dye is accumulated in mitochondria in response to membrane energization. Titration by the inhibitory ligand of mitochondrial uncoupling protein 1 (UCP1), GDP (in presence of substrate), indicated a 3-fold lower sensitivity to GDP in mitochondria from transgenic compared with non-transgenic animals. Binding of [3H]GDP to both types of brown fat mitochondria was measured. Maximum number of specific GDP-binding sites was estimated from Scatchard plots. In accordance with the activity measurements, number of GDP-binding sites was approximately 3- to 5-fold higher in mitochondria isolated from the transgenic animals. (authors)

  12. Brown Adipose YY1 Deficiency Activates Expression of Secreted Proteins Linked to Energy Expenditure and Prevents Diet-Induced Obesity.

    Science.gov (United States)

    Verdeguer, Francisco; Soustek, Meghan S; Hatting, Maximilian; Blättler, Sharon M; McDonald, Devin; Barrow, Joeva J; Puigserver, Pere

    2016-01-01

    Mitochondrial oxidative and thermogenic functions in brown and beige adipose tissues modulate rates of energy expenditure. It is unclear, however, how beige or white adipose tissue contributes to brown fat thermogenic function or compensates for partial deficiencies in this tissue and protects against obesity. Here, we show that the transcription factor Yin Yang 1 (YY1) in brown adipose tissue activates the canonical thermogenic and uncoupling gene expression program. In contrast, YY1 represses a series of secreted proteins, including fibroblast growth factor 21 (FGF21), bone morphogenetic protein 8b (BMP8b), growth differentiation factor 15 (GDF15), angiopoietin-like 6 (Angptl6), neuromedin B, and nesfatin, linked to energy expenditure. Despite substantial decreases in mitochondrial thermogenic proteins in brown fat, mice lacking YY1 in this tissue are strongly protected against diet-induced obesity and exhibit increased energy expenditure and oxygen consumption in beige and white fat depots. The increased expression of secreted proteins correlates with elevation of energy expenditure and promotion of beige and white fat activation. These results indicate that YY1 in brown adipose tissue controls antagonistic gene expression programs associated with energy balance and maintenance of body weight. PMID:26503783

  13. Perception of fatness

    OpenAIRE

    Jałkiewicz, Małgorzata

    1997-01-01

    The study’s objective was to find out whether there is a relationship between bodily fatness traits described with anthropometric measurements and the assessment of the physical attractiveness of people with different degree of fat deposition. Furthermore, an attempt was made to answer the question whether we perceive the physique of another man as a whole or if we pay more attention to certain parts of the body and whether there is a stereotype of desirable fat deposition.

  14. The Effect of Sorafenib, Tadalafil and Macitentan Treatments on Thyroxin-Induced Hemodynamic Changes and Cardiac Abnormalities

    Science.gov (United States)

    Saad, Nancy S.; Floyd, Kyle; Ahmed, Amany A. E.; Mohler, Peter J.

    2016-01-01

    Multikinase inhibitors (e.g. Sorafenib), phosphodiesterase-5 inhibitors (e.g. Tadalafil), and endothelin-1 receptor blockers (e.g. Macitentan) exert influential protection in a variety of animal models of cardiomyopathy; however, their effects on thyroxin-induced cardiomyopathy have never been investigated. The goal of the present study was to assess the functional impact of these drugs on thyroxin-induced hemodynamic changes, cardiac hypertrophy and associated altered responses of the contractile myocardium both in-vivo at the whole heart level and ex-vivo at the cardiac tissue level. Control and thyroxin (500 μg/kg/day)-treated mice with or without 2-week treatments of sorafenib (10 mg/kg/day; I.P), tadalafil (1 mg/kg/day; I.P or 4 mg/kg/day; oral), macitentan (30 and 100 mg/kg/day; oral), and their vehicles were studied. Blood pressure, echocardiography and electrocardiogram were non-invasively evaluated, followed by ex-vivo assessments of isolated multicellular cardiac preparations. Thyroxin increased blood pressure, resulted in cardiac hypertrophy and left ventricular dysfunction in-vivo. Also, it caused contractile abnormalities in right ventricular papillary muscles ex-vivo. None of the drug treatments were able to significantly attenuate theses hemodynamic changes or cardiac abnormalities in thyroxin-treated mice. We show here for the first time that multikinase (raf1/b, VEGFR, PDGFR), phosphodiesterase-5, and endothelin-1 pathways have no major role in thyroxin-induced hemodynamic changes and cardiac abnormalities. In particular, our data show that the involvement of endothelin-1 pathway in thyroxine-induced cardiac hypertrophy/dysfunction seems to be model-dependent and should be carefully interpreted. PMID:27082116

  15. A Fat strange Repeller

    Institute of Scientific and Technical Information of China (English)

    申影; 何阅; 姜玉梅; 何大韧

    2004-01-01

    This article reports an observation on a fat strange repeller, which appears after a characteristic crisis observed in a kicked rotor subjected to a piecewise continuous force field. The discontinuity border in the definition range of the two-dimensional mapping, which describes the system, oscillates as the discrete time develops. At a threshold of a control parameter a fat chaotic attractor suddenly transfers to a fat transient set. The strange repeller, which appears after the crisis, is also a fat fractal. This is the reason why super-transience happens

  16. Seasonal food habits of brown bear (Ursus arctos syriacus Linnaeus, 1758 in Cenral Alborz Protected Area

    Directory of Open Access Journals (Sweden)

    Bagher Nezami Balouchi

    2014-11-01

    Full Text Available Mountains of Central Alborz Protected Area hold a big population of brown bear, the largest varnivore species in Iran. Understanding food habits is crucial to understanding the ecology of the species. Diet influences many ecological and life-history traits, such as spatial distribution, social and foraging behavior, body mass and reproduction. Therefore, during Jun 2006 to May 2007 we had a comprehensive study on brown bear food habits, as the largest omnivorous of the country in Central Alborz Protected Area. Our investigation showed that plant materials composed the main proportion of food items of the brown bears in the spring until mid-summer. Insects, especially ants were predominantly eaten in the first half of summer. As approaching to hibernation period in late autumn, fruits played the main role of bear food items having high fat content. We never witnessed bear attack on wild herbivores. Furthermore, we never found remains of wild herbivores except a few livestock remains in brown bear scats during our survey period. Accordingly, we concluded that brown bears were almost herbivorous in the Central Alborz Protected Area. We never found any bear scats or fresh signs in three consecutive years, between first of December until mid of March. Also, no direct sighting of brown bear was reported to us by local people and game keepers within the mentioned period. Accordingly, it can be concluded that the brown bears hibernate for a period of 3-3.5 months in winter in the Central Alborz Protected Area.

  17. Unequivocal Identification of Brown Adipose Tissue in a Human Infant

    OpenAIRE

    Hu, Houchun H.; Tovar, Jason; Pavlova, Zdena; Smith, Michelle L; Gilsanz, Vicente

    2011-01-01

    We report the unique depiction of brown adipose tissue (BAT) by MRI and computed tomography (CT) in a human three month-old infant. Based on cellular differences between BAT and more lipid-rich white adipose tissue (WAT), chemical-shift MRI and CT were both capable of generating distinct signal contrasts between the two tissues and against surrounding anatomy, utilizing fat-signal fraction metrics in the former and X-ray attenuation values in the latter. While numerous BAT imaging experiments...

  18. 糖皮质激素对高脂饮食肥胖大鼠棕色脂肪和骨骼肌PGC-1αmRNA表达的影响%Effect of glucocorticoid on the expression of PGC-1α mRNA in brown adipose tissue and skeletal muscle of obese rats fed with high-fat diet

    Institute of Scientific and Technical Information of China (English)

    胡小磊; 石建华; 项平; 范艳萍; 苗艳君; 黄咏齐

    2009-01-01

    实时荧光定量PCR方法检测大鼠棕色脂肪和骨骼肌中PPARγ辅激活因子1α(PGC-1α)mRNA的表达.肥胖大鼠棕色脂肪和骨骼肌中PGC-1α mRNA表达水平低于普通大鼠(均P<0.01);应用高剂量糖皮质激素后普通大鼠和肥胖大鼠棕色脂肪和骨骼肌中PGC-1α mRNA表达水平降低.%Real-time fluorescent quantitative PCR was used to examine PGC-1α mRNA expression in brown adipose tissue and skeletal muscle of rats. The results showed that the expression levels of PGC-1α mRNA in brown adipose tissue and skeletal muscle of obese rats were lower than those of the normal ones (all P<0.01). After high dose glucocorticoid treatment, the levels of PGC-1α mRNA expression in brown adipose tissue and skeletal muscle, both in normal and obese rats, were decreased significantly.

  19. Thermoneutrality decreases thermogenic program and promotes adiposity in high-fat diet-fed mice.

    Science.gov (United States)

    Cui, Xin; Nguyen, Ngoc Ly T; Zarebidaki, Eleen; Cao, Qiang; Li, Fenfen; Zha, Lin; Bartness, Timothy; Shi, Hang; Xue, Bingzhong

    2016-05-01

    Brown/beige adipocytes are therapeutic targets to combat obesity due to their abilities to dissipate energy through adaptive thermogenesis. Most studies investigating induction of brown/beige adipocytes were conducted in cold condition (e.g., 4°C); much is unknown about how the thermogenic program of brown/beige adipocytes is regulated in thermoneutral condition (e.g., 30°C), which is within the thermal comfort zone of human dwellings in daily life. Therefore, this study aims to characterize the thermogenic program of brown/beige adipocytes in mice housed under ambient (22°C) versus thermoneutral condition (30°C). Male mice raised at 22°C or 30°C were fed either chow diet or high-fat (HF) diet for 20 weeks. Despite less food intake, chow-fed mice housed at 30°C remained the same body weight compared to mice at 22°C. However, these thermoneutrally housed mice displayed a decrease in the expression of thermogenic program in both brown and white fat depots with larger adipocytes. When pair-fed with chow diet, thermoneutrally housed mice showed an increase in body weight. Moreover, thermoneutrality increased body weight of mice fed with HF diet. This was associated with decreased expression of the thermogenic program in both brown and white fat depots of the thermoneutrally housed mice. The downregulation of the thermogenic program might have resulted from decreased sympathetic drive in the thermoneutrally housed mice evident by decreased expression of tyrosine hydroxylase expression and norepinephrine turnover in both brown and white fat depots. Our data demonstrate that thermoneutrality may negatively regulate the thermogenic program and sympathetic drive, leading to increased adiposity in mice. PMID:27230905

  20. Knockdown of NPY expression in the dorsomedial hypothalamus promotes development of brown adipocytes and prevents diet-induced obesity

    OpenAIRE

    Chao, Pei-Ting; Liang YANG; Aja, Susan; Moran, Timothy H.; Bi, Sheng

    2011-01-01

    Hypothalamic neuropeptide Y (NPY) has been implicated in control of energy balance, but the physiological importance of NPY in the dorsomedial hypothalamus (DMH) remains unclear. Here we report that knockdown of NPY expression in the DMH by adeno-associated virus-mediated RNAi reduced fat depots in rats fed regular chow and ameliorated high-fat diet-induced hyperphagia and obesity. DMH NPY knockdown resulted in development of brown adipocytes in inguinal white adipose tissue through the sympa...

  1. Brown coal and the climate

    International Nuclear Information System (INIS)

    The undisputed aims of a sensible energy policy are safety, reasonable prices, environmental compatibility and saving resources. Each energy source and every form of energy conversion and use has specific advantages and disadvantages which must be weighed up. It is in favour of brown coal that it can succeed in international competition and therefore offers security of supply, economy, productivity and employment. The mining and use of brown coal comply with the highest environmental standards, in international comparison. Against this, mining brown coal by strip mining inevitably involves intervention in the environment and the social structure of the coalfield. Burning brown coal to generate electricity in powerstations is specifically connected with high CO2 emission. (orig.)

  2. Facts about polyunsaturated fats

    Science.gov (United States)

    ... with higher amounts of polyunsaturated fats include: Walnuts Sunflower seeds Flax seeds or flax oil Fish, such as salmon, mackerel, herring, albacore tuna, and trout Corn oil Soybean oil Safflower oil To get the health benefits, you need to replace unhealthy fats with healthy ...

  3. Dietary fat and carcinogenesis

    NARCIS (Netherlands)

    Woutersen, R.A.; Appel, M.J.; Garderen-Hoetmer, A. van; Wijnands, M.V.W.

    1999-01-01

    Epidemiologic investigations have suggested a relationship between dietary fat intake and various types of cancer incidences. Furthermore, epidemiologic studies as well as studies with animal models have demonstrated that not only the amount but also the type of fat consumed is important. At present

  4. Learning about Fats

    Science.gov (United States)

    ... eat a mix of foods — some with higher percentages of fat and some with lower percentages — so that you ... and they insulate nervous system tissue in the body. So fat is not the enemy, but you'll want ...

  5. Glycerol-3-phosphate Acyltransferase Isoform-4 (GPAT4) Limits Oxidation of Exogenous Fatty Acids in Brown Adipocytes

    DEFF Research Database (Denmark)

    Cooper, Daniel E; Grevengoed, Trisha J; Klett, Eric L; Coleman, Rosalind A

    2015-01-01

    loss, because both cold tolerance and response to a β3-adrenergic agonist were similar in both genotypes. Because GPAT4 comprises 65% of the total GPAT activity in brown adipose tissue (BAT), we characterized BAT function. A 45% fat diet increased the Gpat4(-/-) BAT expression of peroxisome......Glycerol-3-phosphate acyltransferase-4 (GPAT4) null pups grew poorly during the suckling period and, as adults, were protected from high fat diet-induced obesity. To determine why Gpat4(-/-) mice failed to gain weight during these two periods of high fat feeding, we examined energy metabolism....... Compared with controls, the metabolic rate of Gpat4(-/-) mice fed a 45% fat diet was 12% higher. Core body temperature was 1 ºC higher after high fat feeding. Food intake, fat absorption, and activity were similar in both genotypes. Impaired weight gain in Gpat4(-/-) mice did not result from increased heat...

  6. A Conversation with Larry Brown

    OpenAIRE

    Dasgupta, Anirban

    2005-01-01

    Lawrence D. Brown was born on December 16, 1940 in Los Angeles, California. He obtained his Ph.D. in mathematics from Cornell University in 1964. He has been on the faculty of the University of California, Berkeley, Cornell University, Rutgers University and, most recently, the Wharton School of the University of Pennsylvania, where he holds the Miers Busch Professorship of Statistics. Professor Brown was President of the Institute of Mathematical Statistics in 1992–1993, Coeditor of The Anna...

  7. Fat Necrosis and Oil Cysts

    Science.gov (United States)

    ... Granular cell tumors Fat necrosis and oil cysts Mastitis Duct ectasia Other non-cancerous breast conditions Summary ... References Previous Topic Granular cell tumors Next Topic Mastitis Fat necrosis and oil cysts Fat necrosis happens ...

  8. Differential fat harvesting

    Directory of Open Access Journals (Sweden)

    Sebastian Torres Farr

    2014-12-01

    Full Text Available Aim: Volume replacement with fillers is regularly performed with the use of diverse volumetric materials to correct different structures around the face, depending on the volume enhancement required and the thickness of the soft tissue envelope. Differential fat harvesting and posterior grafting is performed to place the correct fat parcel size for each target area, expanding the potential applications of fat. Methods: Sixty patients consecutively recruited on a first come basis undergone a facial fat grafting procedure, in private practice setting between March 2012 and October 2013. Fat grafting quantity and quality was predicted for each case. Differential harvesting was performed, with 2 fat parcels size. Processing was performed through washing. Fat infiltration was carried out through small cannulas or needles depending on the treated area. Outcomes were analysed both by the physicians and the patients at 7 days, 1 month, 3 months and 6 months through a perceived satisfaction questionnaire. Parameters considered were downtime or discomfort, skin benefits, volume restoration, reabsorption rate estimated and overall improvement. Results: Full facial differential fat grafting procedure lasted an average of 1.5-2.5 h. Average downtime was 3-4 days. Follow-up was performed to a minimum of 6 months. Both patient and physician overall satisfaction rates were mostly excellent. Adverse events like lumps or irregularities were not encountered. Conclusion: Differential fat harvesting and posterior grafting is a valid alternative, to expand the repertoire of fat use, allow a more homogeneous effect, reduce the potential complications, speed up the process, improve graft survival, and to enhance overall aesthetic outcome.

  9. Characteristics of thyroxine 5'-deiodination in cultured human placental cells. Regulation by iodothyronines.

    OpenAIRE

    Hidal, J T; Kaplan, M. M.

    1985-01-01

    Human and rat placental homogenates convert L-thyroxine (T4) to 3,5,3'-L-triiodothyronine (T3) via a pathway termed type II iodothyronine deiodination. To study regulation of this pathway, cell dispersions were prepared from human placental chorionic-decidual membrane. Dispersed cells deiodinated T4 and 3,3',5'-triiodothyronine (rT3), but not T3, at the 5' position. The reaction was only slightly inhibited by 1 mM 6-n-propylthiouracil, enhanced by dithiothreitol, and substantially inhibited b...

  10. Does amiodarone affect heart rate by inhibiting the intracellular generation of triiodothyronine from thyroxine?

    OpenAIRE

    Lindenmeyer, M.; Spörri, S.; Stäubli, M; Studer, A.; Studer, H

    1984-01-01

    The hypothesis that the antiarrhythmic drug amiodarone slows down the heart rate by its inhibitory action on the intracellular conversion of thyroxine (T4) to 3,5,3' triiodothyronine (T3) was investigated. For this purpose we compared the effect of amiodarone with that of another potent inhibitor of the T4----T3 conversion, i.e. the radiographic contrast medium iopanoic acid, on the heart rate of unanaesthetized guinea-pigs. Both amiodarone and, to an even greater extent, iopanoic acid induce...

  11. Differences in hypothalamic type 2 deiodinase ubiquitination explain localized sensitivity to thyroxine

    OpenAIRE

    Werneck de Castro, Joao Pedro; Fonseca, Tatiana L.; Ueta, Cintia B; McAninch, Elizabeth A.; Abdalla, Sherine; Wittmann, Gabor; Lechan, Ronald M.; Gereben, Balazs; Bianco, Antonio C.

    2015-01-01

    The current treatment for patients with hypothyroidism is levothyroxine (L-T4) along with normalization of serum thyroid-stimulating hormone (TSH). However, normalization of serum TSH with L-T4 monotherapy results in relatively low serum 3,5,3′-triiodothyronine (T3) and high serum thyroxine/T3 (T4/T3) ratio. In the hypothalamus-pituitary dyad as well as the rest of the brain, the majority of T3 present is generated locally by T4 deiodination via the type 2 deiodinase (D2); this pathway is sel...

  12. Simplification in the method of thyroxine measurement by competitive protein-binding analysis.

    Science.gov (United States)

    Lara, P F; Fogaca, J C; Shnaider, J

    1976-01-01

    It has been presented a new technique for measuring thyroxine based on the method first proposed by Murphy & Pattee 1964. This method was compared to Braverman et al. 1971 technique and to Seligson & Seligson's 1971 one. The advantage of the suggested technique consists in making only one radioactivity measuring in the Sephadex column itself, which avoids the risk of contamination and increase of costs. Therefore, it saves time and permits the automatization of the method by the use of an automatic gamma counter for 200 or 300 tubes. PMID:819970

  13. Serum thyroxine concentrations following fixed-dose radioactive iodine treatment in hyperthyroid cats: 62 cases (1986-1989)

    Energy Technology Data Exchange (ETDEWEB)

    Meric, S.M.; Rubin, S.I. (Univ. of Saskatchewan, Saskatoon (Canada))

    1990-09-01

    The medical records of 62 hyperthyroid cats treated with a fixed dose of 4 mCi of radioactive iodine (131I) were reviewed. In 60 cats, serum thyroxine concentrations were determined after treatment, allowing evaluation of treatment success. Eighty-four percent of the cats had normal serum thyroxine concentrations after treatment. Five of the 60 cats (8%) remained hyperthyroxinemic after treatment. Five cats (8%) were hypothyroxinemic when evaluated within 60 days of treatment. Three of these cats had normal serum thyroxine concentrations 6 months after treatment, and none had clinical signs of hypothyroidism. The administration of a fixed dose of 4 mCi of 131I was determined to be an effective treatment for feline hyperthyroidism.

  14. Human multipotent adipose-derived stem cells differentiate into functional brown adipocytes

    DEFF Research Database (Denmark)

    Elabd, Christian; Chiellini, Chiara; Carmona, Mamen;

    2009-01-01

    In contrast to the earlier contention, adult humans have been shown recently to possess active brown adipose tissue with a potential of being of metabolic significance. Up to now, brown fat precursor cells have not been available for human studies. We have shown previously that human multipotent...... adipose-derived stem (hMADS) cells exhibit a normal karyotype and high self-renewal ability; they are known to differentiate into cells that exhibit the key properties of human white adipocytes, that is, uncoupling protein two expression, insulin-stimulated glucose uptake, lipolysis in response to beta...

  15. Tyk2 and Stat3 regulate brown adipose tissue differentiation and obesity.

    OpenAIRE

    Derecka, Marta; Gornicka, Agnieszka; Koralov, Sergei B.; Szczepanek, Karol; Morgan, Magdalena; Raje, Vidisha; Sisler, Jennifer; Zhang, Qifang; Otero, Dennis; Cichy, Joanna; Rajewsky, Klaus; Shimoda, Kazuya; Poli, Valeria; Strobl, Birgit; Pellegrini, Sandra

    2012-01-01

    Mice lacking the Jak tyrosine kinase member Tyk2 become progressively obese due to aberrant development of Myf5+ brown adipose tissue (BAT). Tyk2 RNA levels in BAT and skeletal muscle, which shares a common progenitor with BAT, are dramatically decreased in mice placed on a high fat diet and in obese humans. Expression of Tyk2 or the constitutively active form of the transcription factor Stat3 (CAStat3) restores differentiation in Tyk2−/− brown preadipocytes. Furthermore, Tyk2−/− mice express...

  16. Autoimmune thyroiditis with severe hypothyroidism resistant to the treatment with high peroral doses of thyroxine: case report.

    Science.gov (United States)

    Payer, J; Sladekova, K; Kinova, S; Cesnakova, Z; Killinger, Z; Krizko, M; Klimes, I; Langer, P

    2000-12-01

    Female patient (42 yr) suffered from autoimmune thyroiditis resulting in severe hypothyroidism. She was treated for several years by district physician with the dose of 150 microg L-thyroxine daily. Since the level of TSH was repeatedly very high and no improvement of clinical signs has been observed, she was referred to the Medical Faculty Hospital. Thyroid ultrasound showed remarkable diffuse hypoechogenicity, thyroid scintigraphy showed enlarged thyroid with low 99mTc uptake, TRH test was normal, thin needle biopsy supported autoimmune thyroiditis. X-ray examination showed normal sella turcica and no changes in the pituitary were observed with computer tomography. In spite of increasing the dose of peroral L-thyroxine to 300 microg/d and later to 500 microg/d the clinical status and TSH level did not improve. The patient was originally suspected from malabsorption of thyroxine. However, the test with a large single peroral dose (1000 microg) of L-thyroxine showed a rapid decrease of TSH level (from 126 to 75 mU/l) and increase of total T4 level (from 18 to 64 nmol/l) within 4 hr. Later the patient has been treated with intravenous L-thyroxine (500 microg every 3-4 days for 4 weeks) which resulted in the decrease of TSH level to 10 mU/l and increase of T4 level to 80-100 nmol/l. After that it was concluded that the problem is a poor compliance of the patient who apparently does not actually take the medication, although she always claimed that she is doing so. Referring to some similar cases described in the literature the case was classified as thyroxine pseudomalabsorption. In spite that this problem has been explained to her and her relatives, she refused to take any medication and is consistently neglecting all invitations to further examinations. PMID:11137979

  17. Chronic hyperinsulinemia reduces insulin sensitivity and metabolic functions of brown adipocyte.

    Science.gov (United States)

    Rajan, Sujith; Shankar, Kripa; Beg, Muheeb; Varshney, Salil; Gupta, Abhishek; Srivastava, Ankita; Kumar, Durgesh; Mishra, Raj K; Hussain, Zakir; Gayen, Jiaur R; Gaikwad, Anil N

    2016-09-01

    The growing pandemics of diabetes have become a real threat to world economy. Hyperinsulinemia and insulin resistance are closely associated with the pathophysiology of type 2 diabetes. In pretext of brown adipocytes being considered as the therapeutic strategy for the treatment of obesity and insulin resistance, we have tried to understand the effect of hyperinsulinemia on brown adipocyte function. We here with for the first time report that hyperinsulinemia-induced insulin resistance in brown adipocyte is also accompanied with reduced insulin sensitivity and brown adipocyte characteristics. CI treatment decreased expression of brown adipocyte-specific markers (such as PRDM16, PGC1α, and UCP1) and mitochondrial content as well as activity. CI-treated brown adipocytes showed drastic decrease in oxygen consumption rate (OCR) and spare respiratory capacity. Morphological study indicates increased accumulation of lipid droplets in CI-treated brown adipocytes. We have further validated these findings in vivo in C57BL/6 mice implanted with mini-osmotic insulin pump for 8weeks. CI treatment in mice leads to increased body weight gain, fat mass and impaired glucose intolerance with reduced energy expenditure and insulin sensitivity. CI-treated mice showed decreased BAT characteristics and function. We also observed increased inflammation and ER stress markers in BAT of CI-treated animals. The above results conclude that hyperinsulinemia has deleterious effect on brown adipocyte function, making it susceptible to insulin resistance. Thus, the above findings have greater implication in designing approaches for the treatment of insulin resistance and diabetes via recruitment of brown adipocytes. PMID:27340034

  18. Detection of prion infectivity in fat tissues of scrapie-infected mice.

    Directory of Open Access Journals (Sweden)

    Brent Race

    2008-12-01

    Full Text Available Distribution of prion infectivity in organs and tissues is important in understanding prion disease pathogenesis and designing strategies to prevent prion infection in animals and humans. Transmission of prion disease from cattle to humans resulted in banning human consumption of ruminant nervous system and certain other tissues. In the present study, we surveyed tissue distribution of prion infectivity in mice with prion disease. We show for the first time detection of infectivity in white and brown fat. Since high amounts of ruminant fat are consumed by humans and also incorporated into animal feed, fat-containing tissues may pose a previously unappreciated hazard for spread of prion infection.

  19. Effects of Seasonal Changes, Age and Smoking on Haemostatic Factors and Thyroxine Level in Egyptian Men

    International Nuclear Information System (INIS)

    ONE hundred and twenty male volunteers arranged into 6 equal groups participated in the present study to investigate the influence of age, smoking and season on clot formation, clot lysis and thyroxine hormone. Erythrocyte sedimentation rate, clotting time, platelet count, haemoglobin content, red blood cell count, haematocrit, total leukocytic count, fibrinogen, prothrombin time and concentration, partial thromboplastin time, factor V, VIII, plasminogen and thyroxine hormone were estimated in each group. The effect of age was studied by comparing young individuals (11-16 years) with adult non smokers (30-40 years) . Simultaneously adult non smokers were compared to adult smokers to evaluate the effect of smoking.Three groups: young , adult non smokers and adult smokers during winter were compared with their corresponding groups in summer to assess the season effect.The results revealed that most changes in the three groups were due to temperature variation and the young group had a better thermoregulation control than both adult groups .In non smoker adult group winter caused hypercoagulation with a concomitant increase in fibrinolytic activity as a protective mechanism against thrombus formation. Smoking caused disturbances in many coagulation factors and interaction between smoking and season is evident causing vascular disturbances. In summer smokers are more liable to bleeding, while in winter they are more liable to thrombus formation providing the other condition interfering with bleeding and thrombus formation are constant. There is relative hypothyroidism in smoker group only in summer season

  20. Preparation and separation of the glucuronide and sulfate conjugates of thyroxine and triiodothyronine

    International Nuclear Information System (INIS)

    An enzymatic method for synthesis of labelled thyroxine glucuronide (T4G) and triiodothyronine glucuronide (T3G) from labelled thyroxine (T4) and triiodothyronine (T3) is presented. The synthetic glucuronides are completely digested by beta-glucuronidase, with recovery of the parent T4 or T3. They have distinctive elution patterns on HPLC and on Sephadex G25 chromatography, and can be clearly separated from T4 and T3 as well as from synthetic T4 sulfate (T4S) and T3 sulfate (T3S). On LH 20 chromatography, elution of T4G and T3G is intermediate between that of T4 and T3 and that of T4S and T3S. T3G can be well separated from other thyronines by HPLC alone, but T4G coelutes with rT3 on HPLC; these are then separated by adding a Sephadex G25 chromatography step. Biosynthetic 131I-T3G and 125I-T4G from the bile of a cat given 131I-T3 and 125I-T4 had similar HPLC chromatographic patterns to those of synthetic T3G and T4G. That the identified peaks from analysis of the bile were indeed T3G and T4G was confirmed by recovery of the parent T3 and T4 after beta-glucuronidase digestion

  1. Measurement of free thyroxine and free triiodothyronine concentrations by DPC RIA kits

    International Nuclear Information System (INIS)

    'DPC RIA' kits for measuring free triiodothyronine (T3) and free thyroxine (T4) were fundamentally and clinically studied. Standard curves for incubation temperature and time were favorable. The present kits yielded satisfactory precision and reproducibility. The upper and lower limits of the normal range for T4 were 0.88 ng/dl and 2.08 ng/dl, respectively. The serum concentration of T4 was 3.91 ng/dl or more for hyperthyroidism and 0.57 ng/dl or less for hypothyroidism, allowing discrimination between the two diseases. For T3, the upper and lower limits of the normal range were 1.45 ng/dl and 3.45 ng/dl, respectively. In pregnant women and patients with decreased or increased levels of thyroxine binding globulin (TBG), the serum T3 concentration lay within the normal range. Low free T4 and T3 levels were found in 22 % and 67 %, respectively, of patients with serious non-thyroidal illness (NTI). There was a good correlation between the present kits and the other commercially available kits. Measurements of free T3 and T4 obtained by ''Amerlex RIA'' kits tended to be lower than those by the present kits in pregnant women and NTI patients with hypoalbuminemia. In view of the simplified procedure, satisfactory precision and reproducibility, and the lack of influences of serum albumin and TBG, the present kits have a potential in routine use. (Namekawa, K.)

  2. Serum thyroxine concentrations after radioactive iodine therapy in cats with hyperthyroidism

    Energy Technology Data Exchange (ETDEWEB)

    Meric, S.M.; Hawkins, E.C.; Washabau, R.J.; Turrel, J.M.; Feldman, E.C.

    1986-05-01

    Thirty-one cats with hyperthyroidism were given one dose of radioactive iodine (131I) IV. Serum thyroxine (T4) concentrations were measured before treatment in all cats, at 12-hour intervals after treatment in 10 cats, and at 48-hour intervals after treatment in 21 cats. Serum T4 concentrations also were measured one month after /sup 131/I therapy in 29 cats. Activity of 131I administered was 1.5 to 6.13 mCi, resulting in a dose of 20,000 rads to the thyroid. Serum T4 concentrations before /sup 131/I administration were 5.3 to 51.0 micrograms/dl, with a median T4 concentration of 11.0 micrograms/dl. Serum T4 decreased most rapidly during the first 3 to 6 days after treatment. Sixteen cats (55%) had normal serum thyroxine concentrations by day 4 after 131I administration, and 23 cats (74%) were euthyroxinemic by day 8 after treatment. One month after administration of 131I, the 29 cats evaluated were clinically improved, and 24 (83%) of the 29 cats evaluated had normal serum T4 concentrations, 3 cats (10%) remained hyperthyroxinemic, and 2 cats (7%) were hypothyroxinemic. Therefore, administration of 131I was a safe and effective method to quickly decrease serum T4 concentrations in hyperthyroid cats.

  3. Radioimmunoassay of thyroxine-binding globulin: evaluation of a kit and diagnostic application

    International Nuclear Information System (INIS)

    Serum thyroxine-binding globulin (TBG) was measured by using a radioimmunoassay method. The within-batch of variation (CV) of the assay was 5% or less at different TBG concentrations with a between-batch variation of less than 10%. The mean TBG concentration in hypothyroidism (28.5 plus or minus 6.7 mg/l) was significantly higher, and that in hyperthyroidism (22.3 plus or minus 3.5 mg/l) was significantly lower, than the euthyroid mean (25.4 plus or minus 6.9 mg/l). Acutely ill patients suffering from various non-thyroid illnesses were found to have significantly low mean TBG (13.8 plus or minus 4.3 mg/l). A group of women in late pregnancy had a higher mean value, as expected. Serum TBG level, however, was ineffective as a thyroid function test because of overlapping concentrations between groups. The derived index T4:TBG ratio was found to be superior to free thyroxine index (FTI) in many cases of acutely ill patients, pregnancy and hereditary TBG abnormality. The 95% confidence limit for the ratio in euthyroids, was 2.3 to 7.1. Serum TBG level with T4:TBG ratio is recommended as a replacement for the T3-uptake test and FTI. (author)

  4. Insulin and thyroxine effect on 32P incorporation in the phospholipids of chicken intestinal mucosa

    International Nuclear Information System (INIS)

    Trials were conducted with 56-day-old broiler chickens. The effect was followed up of insulin and alloxan as well as of L-thyroxine and 6-methylthiouracil on 32P incorporation in phospholipids of the duodenal mucosa. A segment of the duodenum was isolated and Na2H32PO4 was introduced therein. The lipids were extracted from duodenal mucosa and the individual phospholipids were separated by means of thin layer chromatography on sillica gel-G. Radioactivity was determined of individual phospholipid fractions. Blood glucose level was studied in insulin and alloxan-treated chickens. The inference was drawn that insulin significantly enhances 32P incorporation in the phospholipids in broiler chicken duodenal mucosa. The drop in blood glucose in insulin-treated chickens is inversely proportional to 32 P inclusion in individual phospholipids of duodenal mucosa. L-thyroxine exerts positive effect in chickens concerning 32P incorporation in lecithin and lysolecithin, this effect being negative with respect to sphingomyelin, cephalin and cardiolipin. Thyroid gland inhibition by 6-methylthiouracil induces negligible decline in 32P inclusion. (author)

  5. Pregnancy outcomes with thyroxine replacement for subclinical hypothyroidism: Role of thyroid autoimmunity

    Directory of Open Access Journals (Sweden)

    Muthukrishnan Jayaraman

    2013-01-01

    Full Text Available Objective: To study pregnancy outcomes in relation to thyroid peroxidase antibody (TPOAb status with optimum thyroxine replacement for subclinical hypothyroidism. Materials and Methods: Ninety-eight women with subclinical hypothyroidism were followed up until the end of their pregnancy. TPO antibody status was performed for 59 women (positive 20, negative 39. Levothyroxine was supplemented to maintain TSH between 0.3-3 mIU/l in all patients, irrespective of TPOAb status. Pregnancy outcomes were noted as pregnancy-induced hypertension (PIH, antepartum or postpartum hemorrhage, preterm delivery, and spontaneous abortion. Outcomes were compared between 3 groups as per TPO antibody status (positive, negative, and undetermined, which were matched for age and gestational period. Results: Thyroid autoimmunity was noted in 34% of women screened for TPO antibody. A total of 11 adverse pregnancy outcomes were recorded (4 spontaneous abortions, 4 preterm deliveries, 3 PIH with no significant difference between the groups. Conclusion: Adverse pregnancy outcomes were not different in the 3 groups with adequate thyroxine replacement for pregnant women with subclinical hypothyroidism targeting TSH in euthyroid range, irrespective of thyroid autoimmunity status.

  6. Brown Adipose Tissue: A New Target for Antiobesity Therapy

    Directory of Open Access Journals (Sweden)

    Anna Meiliana

    2010-08-01

    Full Text Available BACKGROUND: Human fat consist of white and brown adipose tissue (WAT and BAT. Though most fat is energy-storing WAT, the thermogenic capacity of even small amounts of BAT makes it an attractive therapeutic target for inducing weight loss through energy expenditure. CONTENT: Over the past year, several independent research teams used a combination of positron-emission tomography and computed tomography (PET/CT imaging, immunohistochemistry and gene and protein expression assays to prove conclusively that adult humans have functional BAT. BAT is important for thermogenesis and energy balance in small mammals and its induction in mice promotes energy expenditure, reduces adiposity and protects mice from diet-induced obesity. The thermogenic capacity of BAT is impressive. In humans, it has been estimated that as little as 50g of BAT could utilize up to 20% of basal caloric needs if maximally stimulated. SUMMARY: The obesity pandemic requires new and novel treatments. The past few years have witnessed multiple studies conclusively showing that adult humans have functional BAT, a tissue that has a tremendous capacity for obesity-reducing thermogenesis. Novel therapies targeting BAT thermogenesis may be available in the near future as therapeutic options for obesity and diabetes. Thermogenic ingredients may be considered as functional agents that could help in preventing a positive energy balance and obesity. KEYWORDS: brown adipose tissue, thermogenesis, energy expenditure, antiobesity therapy.

  7. Alternative fat sources to animal fat for pigs

    DEFF Research Database (Denmark)

    Lauridsen, Charlotte; Christensen, Thomas Bruun; Halekoh, Ulrich;

    2007-01-01

    % of either animal fat, palm oil mix, palm oil, vegetable oil mix, coconut oil, or rapeseed oil were tested in weaned and growing pigs. It was concluded that several vegetable fat sources (palm oil mix, palm oil, coconut oil, rapeseed oil) could be used as alternatives to animal fat in pig feed, whereas fat...

  8. Fat burn X: burning more than fat.

    Science.gov (United States)

    Hannabass, Kyle; Olsen, Kevin Robert

    2016-01-01

    A 50-year-old man presented with a 2-day history of bilateral lower extremity cramping and dark urine. The patient was found to have a creatine phosphokinase (CPK) elevated of up to 2306 U/L, a serum uric acid of 9.7 mg/dL and 101 red blood cell's per high-powered field on urinalysis. On questioning, the patient endorsed daily exercise with free weights. There were no changes in his regular exercise and medication regimen, no muscle trauma, no recent drug use and no illness. The patient did mention using a new fat burner known as 'Fat Burn X', which he had begun taking 2 days prior to the onset of his muscle cramps. The patient was given normal saline intravenous fluid resuscitation for 48 h with resultant normalisation of his CPK and creatinine, and was discharged with primary care follow-up. PMID:26811412

  9. Facts about saturated fats

    Science.gov (United States)

    ... nih.gov/pubmed/24723079 . Eckel RH, Jakicic JM, Ard, JD, Hubbard VS, de Jesus JM, Lee IM, ... modified dietary fat for preventing cardiovascular disease. Cochrane Database of Systematic Reviews . 2012;5:CD002137. PMID: 22592684 ...

  10. Body Fat Measurement Tools

    Science.gov (United States)

    ... Advisors Press Releases Annual Reports Donations Privacy Policy Advertising Site Map Adults Cyberkitchen Fitness Center Shape Up & Drop 10 Body Fat Lab BMI Calculator Pregnancy Weight Gain Children Assessing Childhood Obesity Pediatric BMI Assessment Overweight Assessment: A Parent's Guide ...

  11. Dietary Fat and Cholesterol

    Science.gov (United States)

    ... Fat Include: Canola Oil Sardines Corn Oil Sesame Seeds Cottonseed Oil Soybeans Flaxseeds Soybean Oil Herring Sunflower Oil Mackerel ... facts label) Palm or Palm Kernal Oil Canola oil Poultry Skin Poultry without the skin Red Meat White meat ...

  12. Fats and Your Child

    Science.gov (United States)

    ... body plans for times when food might be scarce. Fat gives food flavor and texture, but it's ... Eating Well While Eating Out Contact Us Print Resources Send to a friend Reprint Guidelines Share this ...

  13. Fecal Fat: The Test

    Science.gov (United States)

    ... specific nutritional deficiencies in, for example, iron or vitamin B12 . A qualitative fecal fat may be ordered as ... Chronic pancreatitis Pancreatic cancer Cystic fibrosis (affects the function of the pancreas) Shwachman-Diamond Syndrome Diseases and ...

  14. Edible oils and fats

    OpenAIRE

    Kostik, Vesna; Memeti, Shaban; Bauer, Biljana

    2013-01-01

    Edible oils and fats are biological mixtures of plant origin consisting of ester mixtures derived from glycerol with chain of fatty acids. The rate of unsaturated to saturated fatty acids in edible oils and fats is very important for human nutrition. While high levels of saturated fatty acids is desirable to increase oil stability, on the other hand nutritionally they become undesirable, because high levels of saturated fatty acids are frequently considered to have influence in increasing...

  15. Thyroxine and triiodothyronine concentrations in blood and milk during lactation in dairy cows and buffaloes: A longitudinal study

    International Nuclear Information System (INIS)

    The plasma thyroxine (T4) and triiodothyronine (T3) levels in cows and buffaloes during pre-partum, parturition and early, mid- and late lactation stages were measured, as were changes in the concentration of milk T4 and T3 during lactation

  16. Thyroxine (T 4-RIA) and triiodothyronine (T 3-RIA) serum levels in sheep fed on Leucaena Leucocephala

    International Nuclear Information System (INIS)

    The aim of this work is to study the toxicity of Leucaena leucocephala on thyroxine and triiodothyronine serum concentration. Results indicate that ovine T 4 and T 3 serum levels do not decrease with Leucaena leucocephala feeding, sohen proreided for 41 days. (author). 10 refs, 1 tab

  17. Neonatal hypothyrodism: assessment of a commercial kit in which filter-paper discs are used for thyroxine radioimmunoassay

    International Nuclear Information System (INIS)

    The 125I-Neonatal T4 RIA kit is described and evaluated. It is concluded that the kit has acceptable precision and recovery and gives results that correlate well with venous concentrations of circulating thyroxine to allow its use in a congenital hypothyroid screening program

  18. Live-trapping and handling brown bear

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This paper reports techniques developed to live trap and handle brown bears on the Kodiak National Wildlife Refuge. The brown bears (Ursus middendorffi) on the...

  19. Browns Park NWR Water Use Report- 1999

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This report contains locations and water use at Browns Park NWR for 1999. A basic introduction highlighting the region that Browns Park NWR is a part of and the...

  20. Browns Park NWR Water Use Report- 2000

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This report contains locations and water use at Browns Park NWR for 2000. A basic introduction highlighting the region that Browns Park NWR is a part of and the...

  1. M1-M2 balancing act in white adipose tissue browning - a new role for RIP140.

    Science.gov (United States)

    Liu, Pu-Ste; Lin, Yi-Wei; Burton, Frank H; Wei, Li-Na

    2015-01-01

    A "Holy Grail" sought in medical treatment of obesity is to be able to biologically reprogram their adipose tissues to burn fat rather than store it. White adipose tissue (WAT) stores fuel and its expansion underlines insulin resistance (IR) whereas brown adipose tissue (BAT) burns fuel and stimulates insulin sensitivity. These two types of fats seesaw within our bodies via a regulatory mechanism that involves intricate communication between adipocytes and blood cells, particularly macrophages that migrate into adipose deposits. The coregulator, Receptor Interacting Protein 140 (RIP140), plays a key role in regulating this communication. In mice on a high-fat diet, the level of RIP140 in macrophages is dramatically elevated to activate their inflammatory M1 polarization and enhance their recruitment into WAT, facilitating IR. Conversely, lowering the level of RIP140 in macrophages not only reduces M1 macrophages but also expands alternatively polarized, anti-inflammatory M2 macrophages, triggering white adipose tissue browning, fat burning, and restoration of insulin sensitivity. This suggests a potential therapeutic strategy for reversing IR, obesity, and atherosclerotic or even cosmetic fat deposits: therapeutic browning of white adipose deposits by diminishing RIP140 levels in macrophages. PMID:26167418

  2. Inhibition of Sam68 triggers adipose tissue browning.

    Science.gov (United States)

    Zhou, Junlan; Cheng, Min; Boriboun, Chan; Ardehali, Mariam M; Jiang, Changfei; Liu, Qinghua; Han, Shuling; Goukassian, David A; Tang, Yao-Liang; Zhao, Ting C; Zhao, Ming; Cai, Lu; Richard, Stéphane; Kishore, Raj; Qin, Gangjian

    2015-06-01

    Obesity is associated with insulin resistance and type 2 diabetes; molecular mechanisms that promote energy expenditure can be utilized for effective therapy. Src-associated in mitosis of 68 kDa (Sam68) is potentially significant, because knockout (KO) of Sam68 leads to markedly reduced adiposity. In the present study, we sought to determine the mechanism by which Sam68 regulates adiposity and energy homeostasis. We first found that Sam68 KO mice have a significantly reduced body weight as compared to controls, and the difference is explained entirely by decreased adiposity. Interestingly, these effects were not mediated by a difference in food intake; rather, they were associated with enhanced physical activity. When they were fed a high-fat diet, Sam68 KO mice gained much less body weight and fat mass than their WT littermates did, and they displayed an improved glucose and insulin tolerance. In Sam68 KO mice, the brown adipose tissue (BAT), inguinal, and epididymal depots were smaller, and their adipocytes were less hypertrophied as compared to their WT littermates. The BAT of Sam68 KO mice exhibited reduced lipid stores and expressed higher levels of Ucp1 and key thermogenic and fatty acid oxidation genes. Similarly, depots of inguinal and epididymal white adipose tissue (WAT) in Sam68 KO mice appeared browner, their multilocular Ucp1-positive cells were much more abundant, and the expression of Ucp1, Cidea, Prdm16, and Ppargc1a genes was greater as compared to WT controls, which suggests that the loss of Sam68 also promotes WAT browning. Furthermore, in all of the fat depots of the Sam68 KO mice, the expression of M2 macrophage markers was up-regulated, and that of M1 markers was down-regulated. Thus, Sam68 plays a crucial role in controlling thermogenesis and may be targeted to combat obesity and associated disorders. PMID:25934704

  3. Nutrient Regulation: Conjugated Linoleic Acid's Inflammatory and Browning Properties in Adipose Tissue.

    Science.gov (United States)

    Shen, Wan; McIntosh, Michael K

    2016-07-17

    Obesity is the most widespread nutritional disease in the United States. Developing effective and safe strategies to manage excess body weight is therefore of paramount importance. One potential strategy to reduce obesity is to consume conjugated linoleic acid (CLA) supplements containing isomers cis-9, trans-11 and trans-10, cis-12, or trans-10, cis-12 alone. Proposed antiobesity mechanisms of CLA include regulation of (a) adipogenesis, (b) lipid metabolism, (c) inflammation, (d) adipocyte apoptosis, (e) browning or beiging of adipose tissue, and (f) energy metabolism. However, causality of CLA-mediated responses to body fat loss, particularly the linkage between inflammation, thermogenesis, and energy metabolism, is unclear. This review examines whether CLA's antiobesity properties are due to inflammatory signaling and considers CLA's linkage with lipogenesis, lipolysis, thermogenesis, and browning of white and brown adipose tissue. We propose a series of questions and studies to interrogate the role of the sympathetic nervous system in mediating CLA's antiobesity properties. PMID:27431366

  4. 3,5-Diiodo-L-Thyronine Activates Brown Adipose Tissue Thermogenesis in Hypothyroid Rats

    OpenAIRE

    Lombardi, Assunta; Senese, Rosalba; De Matteis, Rita; Busiello, Rosa Anna; Cioffi, Federica; Goglia, Fernando; Lanni, Antonia

    2015-01-01

    3,5-diiodo-l-thyronine (T2), a thyroid hormone derivative, is capable of increasing energy expenditure, as well as preventing high fat diet-induced overweight and related metabolic dysfunction. Most studies to date on T2 have been carried out on liver and skeletal muscle. Considering the role of brown adipose tissue (BAT) in energy and metabolic homeostasis, we explored whether T2 could activate BAT thermogenesis. Using euthyroid, hypothyroid, and T2-treated hypothyroid rats (all maintained a...

  5. 21 CFR 184.1120 - Brown algae.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Brown algae. 184.1120 Section 184.1120 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) FOOD FOR HUMAN... Substances Affirmed as GRAS § 184.1120 Brown algae. (a) Brown algae are seaweeds of the species...

  6. Brain fat embolism

    International Nuclear Information System (INIS)

    Recently CT and MR imaging have demonstrated that cerebral edema is present in cases of fat embolism syndrome. To simulate this we have made a model of brain-fat embolism in rats under MR imaging. In 20 rats, we did intravenous injection of heparinized blood, 1.5 ml·kg-1 taken from femoral bone marrow cavity. Twenty four hours after the injection, we examined the MR images (1.5 tesla, spin-echo method) of brains and histologic findings of brains and lungs were obtained. In 5 of 20 rats, high signal intensity on T2-weighted images and low signal intensity on T1-weighted images were observed in the area of the unilateral cerebral cortex or hippocampus. These findings showed edema of the brains. They disappeared, however, one week later. Histologic examinations showed massive micro-fat emboli in capillaries of the deep cerebral cortex and substantia nigra, but no edematous findings of the brain were revealed in HE staining. In pulmonary arteries, we also found large fat emboli. We conclude that our model is a useful one for the study of brain fat embolism. (author)

  7. Serum proteomic analysis reveals high frequency of haptoglobin deficiency and elevated thyroxine level in heroin addicts.

    Directory of Open Access Journals (Sweden)

    Bing-Ying Zhou

    Full Text Available Heroin addiction is a chronic, complex disease, often accompanied by other concomitant disorders, which may encumber effective prevention and treatment. To explore the differences in expression profiles of serum proteins in control and heroin addicts, we used two-dimensional electrophoresis coupled to MALDI-TOF/TOF, and identified 4 proteins of interest. Following validation of the increase in serum transthyretin, we assessed serum levels of thyroid stimulating hormone (TSH, triiodothyronine (T3, and thyroxine (T4, and observed a robust increase in T4 in heroin addicts compared to controls. In addition, we performed haptoglobin (Hp phenotyping, and showed that the frequency of Hp0 (serum devoid of haptoglobin was significantly higher in heroin addicts. Altogether, these findings indicated that: (1 thyroid hormone imbalance is present in heroin addicts; (2 anhaptoglobinemia (Hp0 might a risk factor or a deleterious effect of heroin abuse.

  8. Conversion of thyroxine to triiodothyronine and reverse triiodothyronine in human placenta and fetal membranes.

    Science.gov (United States)

    Banovac, K; Bzik, L; Tislarić, D; Sekso, M

    1980-01-01

    Conversion of thyroxine (T4) to 3,5,3'-triiodothyronine (T3) and reverse 3,3',5'-triiodothyronine (rT3) was measured in vitro in human placenta and fetal membranes. T4 (5 micrograms/ml) was incubated in 0.15 mol/l phosphate buffer with tissue homogenates for 2 h at 37 degrees C, and the T3 and rT3 generated were determined in ethanol extract using RIA methods. The placenta and chorion homogenates converted more T4 to T3 than to rT3; the placenta was more active than the chorion. In both tissues the highest converting activity was found in microsomal fractions. PMID:7399397

  9. A STUDY OF SYMPTOM SCORE AND LIPID PROFILE IN SUBCLINICAL HYPOTHYROIDISM BEFORE AND AFTER THYROXINE SUPPLEMENTATION

    Directory of Open Access Journals (Sweden)

    Polu Poina

    2015-04-01

    Full Text Available Hypothyroidism is the most common form of thyroid disorder with a broad range of clinical spectrum. Sub clinical hypothyroidism (SH is the mildest form of the disease in which a few if any non - specific symptoms and/or lipid abnormalities are present. The effect of SH on lipid profile is controversial . [1,2] Elevation of total and LDL cholesterol is observed. SH is associated with subtle abnormalties in myocardial contractility, depression, sub fertility and ovalutary dysfunction. Thyroid replacement in SH is associated with improvement in above mentioned symptoms. This study was carried out to analyse symptom score and lipid profile in patients with SH before and after treatment with L - thyroxine.

  10. LIPID PROFILE IN OBESE HYPOTHYROID WOMEN RECEIVING THYROXINE – A CROSS SECTIONAL STUDY

    Directory of Open Access Journals (Sweden)

    Rekha

    2016-02-01

    Full Text Available INTRODUCTION We evaluated serum lipids in obese hypothyroid women receiving L-thyroxine hormone. METHODS A total of 55 obese hypothyroid women receiving levothyroxine treatment, between 20-55 years were included. Blood samples were assessed for thyroid function markers T3, T4, TSH, and serum lipids total cholesterol (TC and triglycerides (TG and Low density lipoprotein (LDL. RESULTS TSH level was significantly increased and T3, T4 concentrations were significantly decreased in clinical hypothyroid patients as compared with euthyroids. Lipid parameters such as TC, TG and LDL were significantly higher in hypothyroid patients. None of the thyroid markers correlated with lipid parameters significantly. CONCLUSION Lipid parameters such as TC, TG and LDL were significantly higher in hypothyroid patients. None of the thyroid function markers correlated significantly with lipid parameters.

  11. Disparate effects of heparin on free thyroxine measured by two different radioimmunoassays

    International Nuclear Information System (INIS)

    Heparin causes a rise in free thyroxine (FT4) measured by equilibrium dialysis (E.D.). With the introduction of at least 4 commercial radioimmunoassays (RIA) for FT4, FT4 measurements have become accepted as one of the best routine thyroid function tests. Investigators have indicated that FT4 levels determined by RIA may be of particular value in patients hospitalized for various severe nonthyroidal illnesses in whom conventional thyroid function tests tend to be abnormal. However, very little information is as yet available on possible effects of various drugs on FT4 levels measured by these new methods. A study was undertaken to evaluate the effect of heparin on FT4 measured by 2 different RIA procedures: RIA-I, GammaCoat FT4 by clinical Assays and RIA-II, Amerlex FT4 by Amersham

  12. Influence of various eluents on TLC of thyroxine triiodothyronine and iodide Pt. 2

    International Nuclear Information System (INIS)

    The Rsub(F) values of L-thyroxine (T4), 3,5,3'-L-triiodothyronine (T3) and iodide (I-) on a thin layer of silica gel have been studied. For the elution, elution systems of iso-alcohols with 2M NH3 and as the third component methanol or ethanol have been used. The study has been carried out with 125-iodine labelled compounds. From the point of view of separation of 125I-T4 from 125I-T3 and 125I- the best properties showed isopropanol-ethanol-2M NH3 (6:2:1) and isopropanol-2M (6:1) mixtures. (author)

  13. Triclosan exposure reduces thyroxine levels in pregnant and lactating rat dams and in directly exposed offspring

    DEFF Research Database (Denmark)

    Petersen, Marta Axelstad; Boberg, Julie; Vinggaard, Anne Marie;

    2013-01-01

    Thyroid disrupting chemicals can potentially disrupt brain development. Two studies investigating the effect of the antibacterial compound triclosan on thyroxine (T4) levels in rats are reported. In the first, Wistar rat dams were gavaged with 75, 150 or 300 mg triclosan/kg bw/day throughout...... rats lactational transfer of triclosan seems limited. Since an optimal study design for testing potential developmental neurotoxicants in rats, should include exposure during both the pre- and postnatal periods of brain development, we suggest that in the case of triclosan, direct dosing of pups may be...... gestation and lactation. Total T4 serum levels were measured in dams and offspring, and all doses of triclosan significantly lowered T4 in dams, but no significant effects on T4 levels were seen in the offspring at the end of the lactation period. Since this lack of effect could be due to minimal exposure...

  14. Triclosan exposure reduces thyroxine levels in pregnant and lactating rat dams and in directly exposed offspring

    DEFF Research Database (Denmark)

    Petersen, Marta Axelstad; Boberg, Julie; Vinggaard, Anne Marie; Christiansen, Sofie; Hass, Ulla

    2013-01-01

    Thyroid disrupting chemicals can potentially disrupt brain development. Two studies investigating the effect of the antibacterial compound triclosan on thyroxine (T4) levels in rats are reported. In the first, Wistar rat dams were gavaged with 75, 150 or 300 mg triclosan/kg bw/day throughout...... gestation and lactation. Total T4 serum levels were measured in dams and offspring, and all doses of triclosan significantly lowered T4 in dams, but no significant effects on T4 levels were seen in the offspring at the end of the lactation period. Since this lack of effect could be due to minimal exposure...... through maternal milk, a second study using direct per oral pup exposure from postnatal day 3–16 to 50 or 150 mg triclosan/kg bw/day was performed. This exposure pointed to significant T4 reductions in 16 day old offspring in both dose groups. These results corroborate previous studies showing that in...

  15. Quality characteristics of chemicals for the radioimmunoassay of thyroxine and thyrotropin

    International Nuclear Information System (INIS)

    Radioimmunoassay is a form of saturation analysis in which the test material competes with labelled antigen for a limited amount of antibody, the amount of label displaced being a measure of the antigen in the test sample. In this country, the kits for Radioimmunoassay (RIA) are imported, and this increase the cost of it. Because this lack of production, the National Institute of Nuclear Research (ININ) has developed RIA's kits for the thyroxine (T4), Thyrotropin (TSH) and Triyodotironine (T3) hormones. This work presents the conclusions of the test recommended by the WHO. The quality test were: recuperation, cross reactions, basic parameters, intra and inter assay variations, sensibility and others. The results show that the RIA's kits of the ININ have a good behavior and can be use in the clinical laboratory. (Author)

  16. Thyroxine and thyrotropin radioimmunoassays using dried blood samples on filter paper for screening of neonatal hypothyroidism

    International Nuclear Information System (INIS)

    A routine and automatized methodology for thyroxine (T4) and thyrotropin (TSH) radioimmunoassay (RIA) using dried blood samples on filter paper is described. Five mm diameter dots were prepared. One eluted dot, corresponding to 4 μl of plasma, was used for T4-RIA while two were necessary for TSH-RIA. Reference filter papers were introduced in each assay for quality control. In a preliminary study on 1903 newborns, samples were obtained, generally between the 5th-7th day. Mean dot T4 was 7.38 +- 2.5 μg/dl. Mean dot TSH was 11.83 +- 9.1 μU/ml, the equation of the regression line between dot TSH (y) and serum TSH (x) being Y = 10.29 + 0.623x. (orig.)

  17. In vitro fluorescence displacement investigation of thyroxine transport disruption by bisphenol A

    Institute of Scientific and Technical Information of China (English)

    Jie Cao; Liang-Hong Guo; Bin Wan; Yin Wei

    2011-01-01

    Bisphenol A (BPA) is a chemical with high production volume and wide applications in many industries.Although BPA is known as an endocrine disruptor, its toxic mechanisms have not been fully characterized.Due to its structural similarity to thyroid hormones thyroxine (T4) and triiodothyronine (T3), one possible mechanism of BPA toxicity is disruption of hormone transport by competitive binding with the transport proteins.In this study, the binding interactions of BPA, T4, and T3 with three thyroid hormone transport proteins, human serum albumin (HSA), transthyretin (TTR), and thyroxine-binding globulin (TBG) were investigated by fluorescence measurement.Using two site-specific fluorescence probes dansylamide and dansyl-L-proline, the binding constants of BPA with HSA at drug site I and site Ⅱ were determined as 2.90 × 104 and 3.14 × 104 L/mol, respectively.By monitoring the intrinsic fluorescence of tryptophan, a binding constant of 4.70 × 103 L/mol was obtained.Similarly, by employing 8-anilino-1-naphthalenesulfonic acid as fluorescence probe, the binding affinity of BPA with TTR and TBG was measured to be 3.10 × 105 and 5.90 × 105 L/mol, respectively.In general, BPA showed lower binding affinity with the proteins than T3 did, and even lower affinity than T4.Using these binding constants, the amount of BPA which would bind to the transport proteins in human plasma was estimated.These results suggest that the concentrations of BPA commonly found in human plasma are probably not high enough to interfere with T4 transport.

  18. Thyroxine therapy ameliorates serum levels of eicosanoids in Chinese subclinical hypothyroidism patients

    Science.gov (United States)

    Zhang, Yan; Zhang, Bing-chang; Xu, Jin; Zhao, Meng; Wang, Zhe; Song, Yong-feng; Zhang, Hai-qing; Gao, Ling; Zhang, Qun-ye; Zhao, Jia-jun

    2016-01-01

    Aim: The eicosanoids derived from phospholipids play key roles in inflammation. However, the profiles of serum eicosanoids in subclinical hypothyroidism (SH) patients and the effects of thyroxine replacement therapy (TRT) on these eicosanoids remain unclear. Many studies show that TSH regulates lipid metabolism. As eicosanoids derived from phospholipids play key roles in oxidative stress and immune function and inflammatory process, it was necessary to explore the profiles of serum eicosanoids in SH patients and the effects of thyroxine replacement therapy (TRT) on the eicosanoids. Methods: A total of 50 Chinese SH patients and 22 healthy volunteers were recruited. SH patients received TRT (L-T4, 25 and 50 mcg/d for patients with TSH≤10.0 mIU/L and TSH>10.0 mIU/L, respectively) for 3 months. Serum levels of major eicosanoids and cPLA2 were analyzed using LC-MS and clinical biochemical assays. Results: The serum levels of cPLA2, eicosanoids (8-isoPGF2a, 11-dehydroTXB2 and 12-HETE) and 11-dehydroTXB2/6-Keto-PGF1a were significantly elevated in SH patients. The serum TSH levels were significantly correlated with the levels of cPLA2 (r=+0.65), 11-dehydroTXB2 (r=+0.32) and 11-dehydroTXB2/6-Keto-PGF1a (r=+0.37). After 3-month TRT, the serum levels of TSH, cPLA2 and the above-mentioned eicosanoids in SH patients were significantly decreased. Conclusion: The metabolism of eicosanoids is significantly altered in Chinese SH patients, and TRT can ameliorate the abnormalities of serum eicosanoid levels. PMID:26997566

  19. Effect of short-term thyroxine administration on energy metabolism and mitochondrial efficiency in humans.

    Directory of Open Access Journals (Sweden)

    Darcy L Johannsen

    Full Text Available The physiologic effects of triiodothyronine (T3 on metabolic rate are well-documented; however, the effects of thyroxine (T4 are less clear despite its wide-spread use to treat thyroid-related disorders and other non-thyroidal conditions. Here, we investigated the effects of acute (3-day T4 supplementation on energy expenditure at rest and during incremental exercise. Furthermore, we used a combination of in situ and in vitro approaches to measure skeletal muscle metabolism before and after T4 treatment. Ten healthy, euthyroid males were given 200 µg T4 (levothyroxine per day for 3 days. Energy expenditure was measured at rest and during exercise by indirect calorimetry, and skeletal muscle mitochondrial function was assessed by in situ ATP flux ((31P MRS and in vitro respiratory control ratio (RCR, state 3/state 4 rate of oxygen uptake using a Clark-type electrode before and after acute T4 treatment. Thyroxine had a subtle effect on resting metabolic rate, increasing it by 4% (p = 0.059 without a change in resting ATP demand (i.e., ATP flux of the vastus lateralis. Exercise efficiency did not change with T4 treatment. The maximal capacity to produce ATP (state 3 respiration and the coupled state of the mitochondria (RCR were reduced by approximately 30% with T4 (p = 0.057 and p = 0.04, respectively. Together, the results suggest that T4, although less metabolically active than T3, reduces skeletal muscle efficiency and modestly increases resting metabolism even after short-term supplementation. Our findings may be clinically relevant given the expanding application of T4 to treat non-thyroidal conditions such as obesity and weight loss.

  20. Effect of magnesium sulfate and thyroxine on inflammatory markers in a rat model of hypothyroidism.

    Science.gov (United States)

    Abbas, Amr M; Sakr, Hussein F

    2016-04-01

    Inflammation is a major risk factor for cardiovascular complications. Magnesium sulfate (MgSO4) has anti-inflammatory actions. Therefore we investigated the effects of levothyroxine and MgSO4 on inflammatory markers as C-reactive protein (CRP), interleukin-6, tumor necrosis factor-α (TNF-α), intercellular adhesion molecule-1 (ICAM-1), and vascular cell adhesion molecule-1 (VCAM-1) in hypothyroid rats. Sixty male rats were divided into 6 groups; normal, normal + MgSO4, hypothyroidism, hypothyroidism + levothyroxine, hypothyroidism + MgSO4, and hypothyroidism + levothyroxine + MgSO4. Thyroxine, triiodothyronine, and thyroid-stimulating hormone (TSH), CRP, interleukin-6, TNF-α, ICAM-1, and VCAM-1 were measured in all rats. Hypothyroidism significantly increased TSH, CRP, interleukin-6, TNF-α, ICAM-1, and VCAM-1 and decreased triiodothronine and thyroxine. Treatment of hypothyroid rats with levothyroxine or MgSO4 significantly decreased CRP, interleukin-6, TNF-α, ICAM-1, and VCAM-1. Combined therapy of hypothyroid rats with levothyroxine and MgSO4 significantly decreased CRP, interleukin-6, TNF-α, ICAM-1, and VCAM-1 compared with hypothyroid rats either untreated or treated with levothyroxine or MgSO4. This study demonstrates that hypothyroid rats have chronic low grade inflammation, which may account for increased risk of cardiovascular diseases. Combined levothyroxine and MgSO4 is better than levothyroxine or MgSO4 alone in alleviating the chronic low grade inflammatory status and therefore reducing the risk of cardiovascular diseases in hypothyroid animals. PMID:26854732

  1. Endothelial Functioning and Hemodynamic Parameters in Rats with Subclinical Hypothyroid and the Effects of Thyroxine Replacement.

    Directory of Open Access Journals (Sweden)

    Cuixia Gao

    Full Text Available Subclinical hypothyroidism (SCH and its associations with atherosclerosis (AS and cardiovascular disease remain controversial. The purpose of our study was to observe changes in endothelial functioning and hemodynamics in rats with SCH and to determine whether L-thyroxine (L-T4 administration affects these changes.In total, sixty male Wistar rats were randomly divided into the following three groups with 20 rats each: control euthyroid rats, SCH rats and SCH rats that had been treated with thyroxine (SCH+T4. The SCH rats were induced by administration of 10 mg x kg(-1 x d(-1 methimazole (MMI once daily by gavage for 3 months. The SCH+T4 rats were administered the same dose of MMI for three months in addition to 2 μg x kg(-1 x d(-1 L-T4 once daily by gavage after 45 days of MMI administration. The control rats received physiological saline via gavage.The SCH group had significantly higher thyroid-stimulating hormone (TSH, total cholesterol (TC, low-density lipoprotein cholesterol (LDL-C, and endothelin (ET levels and a lower nitric oxide (NO level than the control and SCH+T4 groups. The tail and carotid artery blood pressures, left ventricular systolic pressure, heart rate and aorta ventralis blood flow were significantly lower in the SCH group than in the control and SCH+T4 groups. ACH treatment caused concentration-dependent relaxation, which was reduced in the SCH arteries compared with the control and SCH+T4 arteries. Histopathological examination revealed the absence of pathological changes in the SCH rat arteries.These findings demonstrate that L-T4 treatment ameliorates endothelial dysfunction and hemodynamic changes in SCH rats.

  2. Quantification of thyroxine by the selective photoluminescence quenching of L-cysteine–ZnS quantum dots in aqueous solution containing hexadecyltrimethylammonium bromide

    Energy Technology Data Exchange (ETDEWEB)

    Khan, Sarzamin; Carneiro, Leonardo S.A. [Chemistry Department, Pontifícia Universidade Católica do Rio de Janeiro, 22451-900 Rio de Janeiro-RJ (Brazil); Romani, Eric C.; Larrudé, Dunieskys G. [Physics Department, Pontifícia Universidade Católica do Rio de Janeiro, 22451-900, Rio de Janeiro-RJ (Brazil); Aucelio, Ricardo Q., E-mail: aucelior@puc-rio.br [Chemistry Department, Pontifícia Universidade Católica do Rio de Janeiro, 22451-900 Rio de Janeiro-RJ (Brazil)

    2014-12-15

    The determination of L-thyroxine is proposed based on the photoluminescence quenching effect caused on the L-cysteine modified ZnS quantum dots (L-cysteine ZnS QDs) aqueous dispersion. Under optimum conditions, the analytical response followed a Stern–Volmer model and the experimental conditions were adjusted to enable a robust and reproducible photoluminescence signal. The linear response observed in the quantum dots aqueous dispersion covered the L-thyroxine concentration from the LOQ (2.0×10{sup −8} mol L{sup −1}) to 4.0×10{sup −6} mol L{sup −1}. The approach was tested in the determination of L-thyroxine in pharmaceutical formulations used to treat patients with thyroid gland disorder. The percent recoveries in controlled samples were between 93.3 and 103%. Analyte fortified saliva was also evaluated as a possible sample for L-thyroxine monitoring of a patient under treatment. It was identified a static type of photoluminescence quenching caused by L-thyroxine. - Highlights: • L-cysteine ZnS QDs were used as a photoluminescent probe to detect L-thyroxine. • Intensity of probe decreases following a Stern–Volmer model. • The method can detect down ng L{sup −1} levels of L-thyroxine in the probe dispersion. • Method was used to determinate of L-thyroxine in saliva and in pharmaceuticals. • Mechanism of interaction between L-thyroxine and quantum dots was studied.

  3. Fat Embolism Syndrome

    Directory of Open Access Journals (Sweden)

    Gabdullin М.М.

    2012-03-01

    Full Text Available The characteristics of fat embolism syndrome (FES, and the complications occurring in fractures of long bones or pelvic bones are considered. Clinical picture classically develops after “lucid space“, then appear pulmonary and neurological manifestations combined with petechial hemorrhage. Basic theories of FES pathophysiology are analyzed. Early signs are likely to be caused by mechanic vascular occlusion by fat globules. Vascular occlusions in FES are frequently temporary or partial as fat globules block capillary blood flow incompletely due to their flowability and deformity. The diagnosis is made based on clinical presentations using A.R. Gurd’s criteria (1970. Laboratory and instrumental methods are used for clinical diagnosis confirmation or therapy monitoring. The treatment is aimed mainly at supporting respiratory function and hemodynamics stabilization. Prevention, early diagnosis and adequate symptomatic treatment are of primary importance.

  4. α/β-Hydrolase Domain 6 Deletion Induces Adipose Browning and Prevents Obesity and Type 2 Diabetes.

    Science.gov (United States)

    Zhao, Shangang; Mugabo, Yves; Ballentine, Gwynne; Attane, Camille; Iglesias, Jose; Poursharifi, Pegah; Zhang, Dongwei; Nguyen, Thuy Anne; Erb, Heidi; Prentki, Raphael; Peyot, Marie-Line; Joly, Erik; Tobin, Stephanie; Fulton, Stephanie; Brown, J Mark; Madiraju, S R Murthy; Prentki, Marc

    2016-03-29

    Suppression of α/β-domain hydrolase-6 (ABHD6), a monoacylglycerol (MAG) hydrolase, promotes glucose-stimulated insulin secretion by pancreatic β cells. We report here that high-fat-diet-fed ABHD6-KO mice show modestly reduced food intake, decreased body weight gain and glycemia, improved glucose tolerance and insulin sensitivity, and enhanced locomotor activity. ABHD6-KO mice also show increased energy expenditure, cold-induced thermogenesis, brown adipose UCP1 expression, fatty acid oxidation, and white adipose browning. Adipose browning and cold-induced thermogenesis are replicated by the ABHD6 inhibitor WWL70 and by antisense oligonucleotides targeting ABHD6. Our evidence suggests that one mechanism by which the lipolysis derived 1-MAG signals intrinsic and cell-autonomous adipose browning is via PPARα and PPARγ activation, and that ABHD6 regulates adipose browning by controlling signal competent 1-MAG levels. Thus, ABHD6 regulates energy homeostasis, brown adipose function, and white adipose browning and is a potential therapeutic target for obesity and type 2 diabetes. PMID:26997277

  5. Ajustamento para heterogeneidade de variâncias para produção de leite e gordura entre rebanhos da raça Pardo-Suíça no Brasil Adjustment for heterogeneity of variance for milk and fat yield among herds of Brown Swiss in Brazil

    Directory of Open Access Journals (Sweden)

    R.S. Bueno

    2007-04-01

    Full Text Available Para verificar o efeito da inclusão das interações reprodutor x rebanho e reprodutor x rebanho-ano como fator de ajustamento da heterogeneidade de variância, registros de produção de leite e gordura foram estratificados, com base no desvio-padrão fenotípico da produção de leite ajustada, em duas classes: baixo (1.280kg desvio-padrão. Três modelos foram utilizados, sem e com interação reprodutor x rebanho e reprodutor x rebanho-ano, em análises de característica única, geral e em cada classe de desvio-padrão. Médias e componentes de variâncias foram maiores na classe de alto desvio-padrão. Na classe de baixo desvio-padrão, a herdabilidade não se alterou com a inclusão dos efeitos de interação no modelo, sendo de 0,34 para produção de leite e de 0,32 para produção de gordura. Na classe de alto desvio-padrão, as herdabilidades foram: 0,37, 0,35 e 0,36, e de 0,35, 0,32 e 0,35, para produção de leite e gordura, nos modelos sem, com interação reprodutor x rebanho e com interação reprodutor x rebanho-ano, respectivamente. A inclusão do efeito de interação reprodutor x rebanho nos modelos foi significativa (PIn order to verify the effect of including the interactions of sire x herd and the sire x herd-year, as a adjust factor of the variance heterogeneity, registers of milk and fat yields were classified into two classes of standard deviation: low (1.280kg, based on phenotypic standard deviation of the milk production adjusted. Three models, without and with interaction of sire x herd and sire x herd-year, were used in the general univariate analyses and in each standard deviation class. Averages and variance components were higher in the high standard deviation. In the class of low standard deviation, heritability didn't alter with the inclusion of the interaction effects in the model, being of 0.34 for milk yield and 0.32 for fat yield. In the class of high standard deviation, heritabilities were: 0.37, 0.35 and

  6. Exercise and Fat Reduction.

    Science.gov (United States)

    Clarke, H. Harrison, Ed.

    1975-01-01

    This document analyzes the problems encountered by the obese individual and the effects of regular exercise on weight loss and fat reduction. Part one compares the psychological traits of obese children with age groups of normal weight and discusses the organic disorders and social attitudes which plague the overweight individual. Part two states…

  7. That Fat Cat

    Science.gov (United States)

    Lambert, Phyllis Gilchrist

    2012-01-01

    This activity began with a picture book, Nurit Karlin's "Fat Cat On a Mat" (HarperCollins; 1998). The author and her students started their project with a 5-inch circular template for the head of their cats. They reviewed shapes as they drew the head and then added the ears and nose, which were triangles. Details to the face were added when…

  8. Fats for diabetics. (Letter).

    OpenAIRE

    Katan, M B

    1994-01-01

    Opinion. Comments on the treatment of type 2 diabetes from the interaction between nature and nurture. Effective form of treatment for type 2 diabetes; Composition of the diet for diabetics; Identification of unsaturated fats in the diabetic diet; Risks faced by diabetic patients.

  9. Bone marrow fat.

    Science.gov (United States)

    Hardouin, Pierre; Pansini, Vittorio; Cortet, Bernard

    2014-07-01

    Bone marrow fat (BMF) results from an accumulation of fat cells within the bone marrow. Fat is not a simple filling tissue but is now considered as an actor within bone microenvironment. BMF is not comparable to other fat depots, as in subcutaneous or visceral tissues. Recent studies on bone marrow adipocytes have shown that they do not appear only as storage cells, but also as cells secreting adipokines, like leptin and adiponectin. Moreover bone marrow adipocytes share the same precursor with osteoblasts, the mesenchymal stem cell. It is now well established that high BMF is associated with weak bone mass in osteoporosis, especially during aging and anorexia nervosa. But numerous questions remain discussed: what is the precise phenotype of bone marrow adipocytes? What is the real function of BMF, and how does bone marrow adipocyte act on its environment? Is the increase of BMF during osteoporosis responsible for bone loss? Is BMF involved in other diseases? How to measure BMF in humans? A better understanding of BMF could allow to obtain new diagnostic tools for osteoporosis management, and could open major therapeutic perspectives. PMID:24703396

  10. A Matter of Fat.

    Science.gov (United States)

    Calder, Philip C

    2015-09-01

    Acute respiratory disease syndrome (ARDS) is a common complication of critical illness, associated with significant morbidity, prolonged intensive care unit (ICU) and hospital stay, and increased mortality. Inflammation plays a central role in ARDS, with inflammatory eicosanoid mediators produced from the ω-6 fatty acid arachidonic acid, such as leukotriene B4, being involved. The ω-3 fatty acids found in fish oil exert anti-inflammatory effects, including decreasing production of inflammatory eicosanoids from arachidonic acid. The ω-3 fatty acids are effective in models relevant to ARDS. Several randomized controlled trials of enteral formulas rich in ω-3 fatty acids, often in combination with other bioactive substances, have been conducted in patients with ARDS. Four of these trials reported marked clinical benefits, 2 reported no effect, and 1 reported a negative impact. A systematic review and meta-analysis of these 7 trials identified no overall effect on ventilator-free days or on ICU-free days. There was a small reduction in ICU length of stay and no overall effect on mortality. However, the authors formally identified that trials that used high fat in both treatment and control groups showed a significant reduction in mortality, while trials that used a high, or higher, fat treatment and a low-fat control group showed a trend toward an increase in mortality. It is concluded that differences in outcome reported among these studies largely relate to the relative fat contents of the treatment and control formulas. Further, it is concluded that high-fat enteral formulas should not be used in this patient group. PMID:25533963

  11. Photometric brown-dwarf classification

    CERN Document Server

    Skrzypek, N

    2013-01-01

    We have developed a method "photo-type" to identify and accurately classify L and T dwarfs, onto the standard system, from photometry alone. We combine SDSS, UKIDSS and WISE data and classify point sources by comparing the izYJHKW1W2 colours against template colours for quasars, stars, and brown dwarfs. In a sample of $6.5\\times10^6$ bright point sources, J$<$17.5, from 3150 deg$^2$, we identify and type 898 L and T dwarfs, making this the largest homogeneously selected sample of brown dwarfs to date. The sample includes 713 (125) new (previously known) L dwarfs and 21 (39) T dwarfs. For the previously-known sources, the scatter in the plot of photo-type vs spectral type indicates that our photo-types are accurate to 1.5 (1.0) sub-types rms for L (T) dwarfs. Peculiar objects and candidate unresolved binaries are identified.

  12. TEMPORAL AND SPATIAL VARIATION IN PLASMA THYROXINE (T4) CONCENTRATIONS IN JUVENILE ALLIGATORS COLLECTED FROM LAKE OKEECHOBEE AND THE NORTHERN EVERGLADES, FLORIDA, USA

    Science.gov (United States)

    We examined variation in plasma thyroxine (T4) in juvenile American alligators (Alligator mississippiensis) collected from three sites within the Kissimmee River drainage basin (FL, USA). Based on historical sediment data, Moonshine Bay served as the low contaminant exposure site...

  13. Study on changes of serum lipid profile after withdrawl of levo-thyroxine replacement therapy in patients with radical thyroidectomy for cancer

    International Nuclear Information System (INIS)

    Objective: To study the changes of serum lipid profile after withdrawl of levo-thyroxine replacement for 4 weeks in patient with radical thyroidectomy for cancer. Methods: Serum thyroid hormones (FT3, FT4, sTSH, with RIA) levels and lipid profile (Total cholesterol, triglycerides, LDL, HDL, apolipoprotein A-I, apolipoprotein B and Lp (a), with biochemistry) were determined in 46 patients with thyroid carcinoma after operation both during and after 4 weeks' withdrawl of levo-thyroxine replacement treatment. Results: Serum FT3, FT4 levels decreased significantly and serum sTSH, TC, TG, LDL, apo-B, Lp (a) levels increased significantly after 4 weeks' withdrawl of levo-thyroxine replacement (vs during treatment, P 0.05). Conclusion: Hyperlipidaemia did develop in the hypothyroid patients after withdrawl of levo-thyroxine replacement but the degree of which did not not necessarily correlate with the increment of sTSH levels. (authors)

  14. Microlensing, Brown Dwarfs and GAIA

    CERN Document Server

    Evans, N W

    2014-01-01

    The GAIA satellite can precisely measure the masses of nearby brown dwarfs and lower main sequence stars by the microlensing effect. The scientific yield is maximised if the microlensing event is also followed with ground-based telescopes to provide densely sampled photometry. There are two possible strategies. First, ongoing events can be triggered by photometric or astrometric alerts by GAIA. Second, events can be predicted using known high proper motion stars as lenses. This is much easier, as the location and time of an event can be forecast. Using the GAIA source density, we estimate that the sample size of high proper motion ($>300$ mas yr$^{-1}$) brown dwarfs needed to provide predictable events during the 5 year mission lifetime is surprisingly small, only of the order of a hundred. This is comparable to the number of high proper motion brown dwarfs already known from the work of the UKIDSS Large Area Survey and the all-sky WISE satellite. Provided the relative parallax of the lens and the angular Ein...

  15. 2,3,7,8-Tetrachlorodibenzo-p-dioxin (TCDD) as a potent and persistent thyroxine agonist: a mechanistic model for toxicity based on molecular reactivity.

    OpenAIRE

    McKinney, J D; Fawkes, J; Jordan, S; Chae, K; Oatley, S; Coleman, R. E.; Briner, W

    1985-01-01

    TCDD and thyroxine have common molecular reactivity properties which enable them to present a planar face and lateral halogens in interactions with proteins. These molecular properties are consistent with the structure-toxicity relationship for TCDD and related compounds. Biological evidence is discussed including preliminary studies on the effects of TCDD exposure on tadpole growth and development which is consistent with the possible thyroxine-like activity of TCDD. The work suggests the po...

  16. Role of serum carrier proteins in the peripheral metabolism and tissue distribution of thyroid hormones in familial dysalbuminemic hyperthyroxinemia and congenital elevation of thyroxine-binding globulin.

    OpenAIRE

    Bianchi, R.; Iervasi, G; Pilo, A.; Vitek, F; Ferdeghini, M; Cazzuola, F; Giraudi, G

    1987-01-01

    To investigate the role of thyroxine-binding globulin (TBG) and albumin in the availability of thyroid hormones to peripheral tissues, comprehensive kinetic studies of thyroxine (T4) and triiodothyronine (T3) were carried out in eight subjects with familial dysalbuminemic hyperthyroxinemia (FDH), in four subjects with inherited TBG excess, and in 15 normals. In high-TBG subjects, the reduction of T4 and T3 plasma clearance rates (by 51% and 54%, respectively) was associated with normal daily ...

  17. The effects of dexamethasone (DXM) and vitamin A on the growth and metamorphosis of gamma irradiated, thyroxine induced Bufo melanostictus tadpoles

    International Nuclear Information System (INIS)

    This study deals with the effects of vitamin A and dexamethasone (DXM) on the metamorphosis of irradiated tadpoles. Results indicate that hypervitaminosis A depresses the metamorphosing action of thyroxine for several days. On the contrary, dexamethasone accelerates the action of exogenous thyroxine on tadpoles. Thus present data suggest that DXM supresses STH synthesis and promotes TSH secretion. Moreover, muscle appears to be its target tissue and DXM seems to promote the proteolytic digestion of the larval tail. (author)

  18. Thyroid hormones and thyroxine-binding globulin in relation to liver function and serum testosterone in men with alcoholic cirrhosis

    DEFF Research Database (Denmark)

    Becker, U; Gluud, C; Bennett, Patrick

    1988-01-01

    In 73 euthyroid male patients with histologically verified alcoholic cirrhosis, thyroid hormones, thyroxine-binding globulin (TBG) and testosterone concentrations (total, non-protein- and non-SHBG-bound) were studied in relation to each other and to the degree of liver dysfunction. Serum concentr......In 73 euthyroid male patients with histologically verified alcoholic cirrhosis, thyroid hormones, thyroxine-binding globulin (TBG) and testosterone concentrations (total, non-protein- and non-SHBG-bound) were studied in relation to each other and to the degree of liver dysfunction. Serum...... correlated significantly (Kendall Tau-beta = -0.33, p = 0.001) with total serum testosterone concentrations, while there was a negative correlation (Kendall Tau-beta = -0.20, p = 0.025) between testosterone and TSH values. No correlation was found between testosterone concentrations and serum levels of TBG...

  19. High-fat diet leads to tissue-specific changes reflecting risk factors for diseases in DBA/2J mice

    OpenAIRE

    Hageman, Rachael S.; Wagener, Asja; Hantschel, Claudia; Svenson, Karen L.; Churchill, Gary A; Brockmann, Gudrun A., 1958-

    2010-01-01

    The aim of this study was to characterize the responses of individual tissues to high-fat feeding as a function of mass, fat composition, and transcript abundance. We examined a panel of eight tissues [5 white adipose tissues (WAT), brown adipose tissue (BAT), liver, muscle] obtained from DBA/2J mice on either a standard breeding diet (SBD) or a high-fat diet (HFD). HFD led to weight gain, decreased insulin sensitivity, and tissue-specific responses, including inflammation, in these mice. The...

  20. The peripheral conversion of thyroxine (T4) into triiodothyronine (T3) and reverse triiodothyronine (rT3)

    International Nuclear Information System (INIS)

    The aim of this study was to delineate several physiological, pathological and pharmacological factors involved in the peripheral conversion of thyroxine (T4), using radioimmunoassay. The determination of normal values of these tests under basal circumstances and after stimulation with thyrotropin-releasing-hormone is presented, and some physiological factors which may modulate the conversion of T4 are discussed. Results are presented of the thyroid function tests in patients with thyroid disease and with acute non-thyroidal diseases. (Auth.)

  1. Developmental Coexposure to Polychlorinated Biphenyls and Polybrominated Diphenyl Ethers Has Additive Effects on Circulating Thyroxine Levels in Rats

    OpenAIRE

    Miller, Veronica M; Sanchez-Morrissey, Susana; Brosch, Karl O; Seegal, Richard F.

    2012-01-01

    Polychlorinated biphenyls (PCBs) and polybrominated diphenyl ethers (PBDEs) are widespread environmental contaminants found in seafood and dairy products. PCBs and PBDEs are structurally similar chemicals and affect thyroid hormone function and behavior in children and laboratory rodents. Although coexposure frequently exists, the in vivo developmental effects of combined exposure to PCBs and PBDEs on thyroxine (T4) levels are unknown. We examined the effects of PCB and PBDE coexposure from g...

  2. [Influence of thyroxine on display of dexamethasone's effects on M-response's parameters of skeletal muscle of white rats].

    Science.gov (United States)

    2013-09-01

    In the studies on white rats-females it was studied the dynamics of the change of some parameters of the M-response of a forward tibial muscle in the process of dexamethasone injection (in a dose of 0.25 mg/kg), applied separately and combined with injection of thyroxine (in a dose of 10 mkg/kg). It was established that the application of thyroxine in a complex with dexamethasone prevented the lengthening of the latent period, the decrease of amplitude and the shortening of the duration of the M-responses, taking place at the isolated injection of dexamethasone and also caused an essential decrease of frequency of polyphase potentials of the muscle. Besides, thyroxine prevented the development of the essential decrement of the amplitude and the lengthening of the latent period of M-responses in the process of indirect electric stimulation of the muscle with a frequency of 4 imp/s, typical of the isolated application of dexamethasone. PMID:25507818

  3. Automated measurement of serum thyroxine with the ''AIRA II,'' as compared with competitive protein binding and radioimmunoassay

    International Nuclear Information System (INIS)

    Two conventional serum thyroxine assays, run in separate laboratories, one by competitive protein binding and one by radioimmunoassay, were used to evaluate the automated ARIA II (Becton Dickinson Immunodiagnostics) serum thyroxine assay. Competitive protein binding as compared to ARIA II with 111 clinical serum samples gave a slope of 1.04 and a correlation coefficient of 0.94. The radioimmunoassay comparison to ARIA II with 53 clinical serum samples gave a slope of 1.05 and a correlation coefficient of 0.92. The ARIA II inter-assay coefficient of variation for 10 replicates of low, medium, and high thyroxine serum samples was 6.2, 6.0, and 2.9%, respectively, with an inter-assay coefficient of variation among 15 different assays of 15.5, 10.1, and 7.9%. The automated ARIA II, with a 2.2-min cycle per sample, gives results that compare well with those by manual methodology

  4. The trochanteric fat pad

    Directory of Open Access Journals (Sweden)

    P. Panettiere

    2011-05-01

    Full Text Available Technological developments based on the use of autologous white adipose tissue (WAT attracted attention to minor fat depots as possible sources of adipose tissue. In plastic surgery, the trochanteric fatty pad is one of the most used WAT depots for its location and organoleptic characteristics that make it particularly suitable for reconstructive procedures. Despite its wide use in clinic, the structure of this depot has never been studied in detail and it is not known if structural differences exist among trochanteric fat and other subcutaneous WAT depots. The present study was performed on trochanteric fat pad with the aim to clarify the morphology of its adipocytes, stroma and microcirculation, with particular reference to the stem niches. Histological and ultrastructural studies showed that the main peculiar feature of the trochanteric fat concerns its stromal component, which appears less dense than in the other subcutaneous WATs studied. The intra-parenchymal collagen stroma is poor and the extracellular compartment shows large spaces, filled with electron-light material, in which isolated collagen bundles are present. The adipocytes are wrapped in weak and easily detachable collagen baskets. These connective sheaths are very thin compared to the sheaths in other subcutaneous WAT depots. The capillaries are covered by large, long and thin elements surrounded by an external lamina; these perivascular cells are poor in organelles and mainly contain poly-ribosomes. In conclusion, when compared to other WAT deposits, the trochanteric fatty pad shows structural peculiarities in its stroma and microcirculation suggesting a high regenerative potential. Resistance, dissociability, microvascular weft and high regenerative potential make the trochanteric fatty pad a privileged source for harvesting in autologous WAT-based regenerative procedures.

  5. Cerebral fat embolism

    International Nuclear Information System (INIS)

    A case of cerebral fat embolism is reported. A 18-year-old patient with multiple bone fractures was in semiconma immediately after an injury. Brain CT showed no brain swelling or intracranial hematoma. Hypoxemia and alcoholemia were noted on admission, which returned to normal without improvement of consciousness level. In addition, respiratory symptoms with positive radiographic changes, tachycardia, pyrexia, sudden drop in hemoglobin level, and sudden thrombocytopenia developed. These symptoms were compatible with Gurd's criteria of systemic fat embolism. Eight days after injury, multiple low density areas appeared on CT and disappeared within the subsequent two weeks, and subdural effusion with cerebral atrophy developed. These CT findings were not considered due to cerebral trauma. Diagnosis of cerebral fat embolism was made. The subdural effusion was drained. Neurologic and pulmonary recoveries took place slowly and one month following the injury the patient became alert and exhibited fully coordinated limb movement. The CT scans of the present case well corresponded with hitherto reported pathological findings. Petechiae in the white matter must have developed on the day of injury, which could not be detected by CT examination. It is suggested that some petechial regions fused to purpuras and then gradually resolved when they were detected as multiple low density areas on CT. CT in the purpuras phase would have shown these lesions as high density areas. These lesions must have healed with formation of tiny scars and blood pigment which were demonstrated as the disappearance of multiple low density areas by CT examination. Cerebral atrophy and subsequent subdural effusion developed as a result of demyelination. The patient took the typical clinical course of cerebral fat embolism and serial CT scans served for its assessment. (author)

  6. Get the fat out!

    Science.gov (United States)

    Ignatenko, Natalia A; Gerner, Eugene W

    2013-03-01

    Obesity is associated with increased risk of a number of cancers in humans, but the mechanism(s) responsible for these associations have not been established. It is estimated that 68% of adults are overweight or obese and that obesity may be causative in 4% to 7% of cancers in the United States. Several hypotheses have been put forward to explain the association between obesity and cancer including adipose-directed signaling (e.g., mTOR, AMPK), production of factors (e.g., insulin growth factor 1, fibroblast growth factor 1, and/or chronic inflammation associated with obesity. Huffman and colleagues used surgical methods to determine if visceral fat was causally related to intestinal tumorigenesis in the Apc(1638/N+) mouse in a manner independent of confounding factors such as caloric restriction. They found that caloric restriction could extend survival in both male and female Apc(1638/N+) mice but found that surgical removal of visceral fat was only effective in reducing macroadenomas in females. The results of this study do not identify the specific mechanism of association between visceral fat and intestinal carcinogenesis in female mice but do support the rationale for future cancer prevention trials that evaluate pharmacologic and behavioral strategies to reduce abdominal obesity in humans. Cancer Prev Res; 6(3); 161-4. ©2013 AACR. PMID:23466814

  7. [Spuriously healthy plant fats].

    Science.gov (United States)

    Cichosz, Grazyna; Czeczot, Hanna

    2011-10-01

    Since long plant fats are considered by nutritionists, dieticians and doctors, as main source of essential unsaturated fatty acids) n-6 and n-3 in human diet. On the market there is plenty of oils that can be consumed directly or used to frying. Last four decades consumption of oils increased several times due to stimulated by advertisement popularization of their pro-health activity. Plant oils supply mostly multi unsaturated fatty acids n-6 excess of which disadvantageously influence human health. Determinations of changes of oxidative stability of plant fats (during processing and storage) proved that consumption of oxidation products of fatty acids and sterols may be a reason of various diseases. Both epidemiologic and clinic studies indicated that if plant fats (both oils except this from olives and margarines) have possessed pro-health properties, their several times increased consumption would liquidate the problem of arteriosclerosis and its clinical complications (heart attack, stroke). For the present, every second death in the industrial countries results from the cardiovascular disease. Morbidity of cancer is also increasing and of neurological and neurodegenerative diseases is growing up vigorously. PMID:22097183

  8. The role of active brown adipose tissue in human metabolism

    Energy Technology Data Exchange (ETDEWEB)

    Ozguven, Salih; Turoglu, H.T. [S.B. Marmara Universitesi Pendik Egitim ve Arastirma Hastanesi, Department of Nuclear Medicine, Istanbul (Turkey); Ones, Tunc [S.B. Marmara Universitesi Pendik Egitim ve Arastirma Hastanesi, Department of Nuclear Medicine, Istanbul (Turkey); Kozyatagi/Kadikoy, Istanbul (Turkey); Yilmaz, Yusuf; Imeryuz, Nese [S.B. Marmara Universitesi Pendik Egitim ve Arastirma Hastanesi, Department of Internal Medicine, Division of Gastroenterology, Istanbul (Turkey)

    2016-02-15

    The presence of activated brown adipose tissue (ABAT) has been associated with a reduced risk of obesity in adults. We aimed to investigate whether the presence of ABAT in patients undergoing {sup 18}F-FDG PET/CT examinations was related to blood lipid profiles, liver function, and the prevalence of non-alcoholic fatty liver disease (NAFLD). We retrospectively and prospectively analysed the {sup 18}F-FDG PET/CT scans from 5,907 consecutive patients who were referred to the Nuclear Medicine Department of the Marmara University School of Medicine from outpatient oncology clinics between July 2008 and June 2014 for a variety of diagnostic reasons. Attenuation coefficients for the liver and spleen were determined for at least five different areas. Blood samples were obtained before PET/CT to assess the blood lipid profiles and liver function. A total of 25 of the 5,907 screened individuals fulfilling the inclusion criteria for the study demonstrated brown fat tissue uptake [ABAT(+) subjects]. After adjustment for potential confounders, 75 individuals without evidence of ABAT on PET [ABAT(-) subjects] were enrolled for comparison purposes. The ABAT(+) group had lower total cholesterol, low-density lipoprotein cholesterol, alanine aminotransferase, and aspartate transaminase levels (p < 0.01), whereas we found no significant differences in the serum triglyceride and high-density lipoprotein cholesterol levels between the two groups. The prevalence of NAFLD was significantly lower in ABAT(+) than in ABAT(-) subjects (p < 0.01). Our study showed that the presence of ABAT in adults had a positive effect on their blood lipid profiles and liver function and was associated with reduced prevalence of NAFLD. Thus, our data suggest that activating brown adipose tissue may be a potential target for preventing and treating dyslipidaemia and NAFLD. (orig.)

  9. The role of active brown adipose tissue in human metabolism

    International Nuclear Information System (INIS)

    The presence of activated brown adipose tissue (ABAT) has been associated with a reduced risk of obesity in adults. We aimed to investigate whether the presence of ABAT in patients undergoing 18F-FDG PET/CT examinations was related to blood lipid profiles, liver function, and the prevalence of non-alcoholic fatty liver disease (NAFLD). We retrospectively and prospectively analysed the 18F-FDG PET/CT scans from 5,907 consecutive patients who were referred to the Nuclear Medicine Department of the Marmara University School of Medicine from outpatient oncology clinics between July 2008 and June 2014 for a variety of diagnostic reasons. Attenuation coefficients for the liver and spleen were determined for at least five different areas. Blood samples were obtained before PET/CT to assess the blood lipid profiles and liver function. A total of 25 of the 5,907 screened individuals fulfilling the inclusion criteria for the study demonstrated brown fat tissue uptake [ABAT(+) subjects]. After adjustment for potential confounders, 75 individuals without evidence of ABAT on PET [ABAT(-) subjects] were enrolled for comparison purposes. The ABAT(+) group had lower total cholesterol, low-density lipoprotein cholesterol, alanine aminotransferase, and aspartate transaminase levels (p < 0.01), whereas we found no significant differences in the serum triglyceride and high-density lipoprotein cholesterol levels between the two groups. The prevalence of NAFLD was significantly lower in ABAT(+) than in ABAT(-) subjects (p < 0.01). Our study showed that the presence of ABAT in adults had a positive effect on their blood lipid profiles and liver function and was associated with reduced prevalence of NAFLD. Thus, our data suggest that activating brown adipose tissue may be a potential target for preventing and treating dyslipidaemia and NAFLD. (orig.)

  10. The Possible Potentiating Role of Endoplasmic Reticulum Stress Response Inhibitors in Trans-Differentiation of white to Brown Adipocytes

    Directory of Open Access Journals (Sweden)

    Ali Mohammad Sharifi

    2012-01-01

    Full Text Available The brown adipose tissue (BAT is an organ with the specialised function of intracellular fat oxidation; in other words, brown fat points to a potential natural tool by which energy expenditure is being stimulated. Obesity is a serious illness which can lead to many medical complications such as cardiovascular disorders. The BAT production, therefore, could be a promising therapeutic strategy for managing obesity. While different approaches have been examined to generate brown adipocytes from various precursor cells, no study has proposed an efficient procedure for direct trans-differentiation of white to brown adipocytes. Bone morphogenic protein (BMP-7 is a possible potential agent by which most of the main factors involved in induction of brown adipocytogenesis such as early regulators of brown fat fate, positive regulatory domain containing 16 (PRDM16 and peroxisome proliferator-activated receptor gamma (PPARγ coactivator-1 alpha (PGC-1α are stimulated, but the rate of success was not so promising. It has been documented that mature white adipocytes exert endoplasmic reticulum stress response (ESR and consequently unfolded protein response (UPR becomes activated for the purpose of ESR recovery since the ESR exceeds the capacity of UPR to overcome the imposed stress, and in turn disables the cell to manage the protein synthesis cascade including those required for BMP-7 induction of brown adipogenesis. This was performed using three main ESR sensors: PKR-like endoplasmic reticulum kinase (PERK, inositol requiring enzyme-1 (IRE-1 and activating transcription factor 6 alpha (ATF-6α resulting in attenuation of protein translation by blocking the activation of transcriptional machinery of UPR genes and the cell behaviour would also be changed towards apoptosis.It may suggest and propose the hypothesis that pretreatment of the white adipocyte with an ESR inhibitor such as salubrinal by reducing ESR and turning on the protein synthesis machinery

  11. Surprising Legacies of Brown v. Board

    OpenAIRE

    Minow, Martha Louise

    2014-01-01

    Perhaps the most powerful legacy of Brown v. Board is this: opponents in varied political battles fifty years later each claim ties to the decision and its meaning. So although the analogy between Brown and same-sex marriage has divided Black clergy, each side vies to inherit the civil rights heritage. President George W. Bush invoked Brown in opposing race-conscious college admission practices. The success of Brown in reshaping the moral landscape has been so profound that I fear we do not f...

  12. BROWN TUMOR OF THE FACIAL BONES

    Directory of Open Access Journals (Sweden)

    Violeta Trandafir

    2010-11-01

    Full Text Available Brown tumor arises as a direct result of the effect of parathyroid hormone on bone tissue in some patients with hyperparathyroidism. The lesion localizes in areas of intense bone resorbtion, and the bone defect becomes filled with fibroblastic tissue that can deform the bone and simulate a neoplastic process. Brown tumors can affect the mandible, maxilla, clavicle, ribs and pelvic bones. Most patients with hyperparathyroidism are asymptomatic. Skeletal changes may represent the first manifestations of the disease. Radiologically, brown tumor in the jaws presents as a well-defined radiolucent osteolytic lesion, making it hard to differentiate it from other maxillary expansive lesions that can present with a similar imaging. Brown tumors exhibit no pathognomonic histologic changes. Differentiating between a brown tumor and other giant-cell tumors may be very difficult, even with histology. A final diagnosis can be defined only by evaluating the radiological findings with histopathological, laboratory and clinical data. At present, brown tumor is considered as a reparative cellular process rather than a real neoplasia. This phenomenon is considered as pathognomonic of hyperparathyroidism secondary to renal failure, especially in patients on long-term hemodialysis. The initial treatment of brown tumor involves control of hyperparathyroidism, regardless of whether it is primary or secondary. The clinical management of brown tumor aims primarily to reduce the elevated parathyroid hormone levels by pharmacological treatment. Surgical treatment is reserved to nonresponders or to patients with painful symptomatology or alteration of normal function. Brown tumor can recur if hyperparathyroidism persists or recurs.

  13. The Engrailed-1 Gene Stimulates Brown Adipogenesis

    Directory of Open Access Journals (Sweden)

    Chuanhai Zhang

    2016-01-01

    Full Text Available As a thermogenic organ, brown adipose tissue (BAT has received a great attention in treating obesity and related diseases. It has been reported that brown adipocyte was derived from engrailed-1 (EN1 positive central dermomyotome. However, functions of EN1 in brown adipogenesis are largely unknown. Here we demonstrated that EN1 overexpression increased while EN1 knockdown decreased lipid accumulation and the expressions of key adipogenic genes including PPARγ2 and C/EBPα and mitochondrial OXPHOS as well as BAT specific marker UCP1. Taken together, our findings clearly indicate that EN1 is a positive regulator of brown adipogenesis.

  14. Misleading results from immunoassays of serum free thyroxine in the presence of rheumatoid factor.

    Science.gov (United States)

    Norden, A G; Jackson, R A; Norden, L E; Griffin, A J; Barnes, M A; Little, J A

    1997-06-01

    A novel interference with measurements of serum free thyroxine (FT4) caused by rheumatoid factor (RhF) is described. We found misleading, sometimes gross, increases of FT4 results in 5 clinically euthyroid elderly female patients with high RhF concentrations. All 5 patients had high FT4 on Abbott AxSYM or IMx analyzers. "NETRIA" immunoassays gave misleading results in 4 of the 5 patients; Amerlex-MAB in 2 of 4 patients; AutoDELFIA in 2 of the 5; and Corning ACS-180 and Bayer Diagnostics Immuno 1 in 1 of the 5. BM-ES700 system results for FT4 in these women remained within the reference range. Results for serum T4, thyroid-stimulating hormone, free triiodothyronine, thyroid-hormone-binding globulin, and FT4 measured by equilibrium dialysis were normal in all 5 patients. Drugs, albumin-binding variants, and anti-thyroid-hormone antibodies were excluded as interferences. Addition to normal serum of the RhF isolated from each of the 5 patients increased the apparent FT4 (Abbott AxSYM). Screening of 83 unselected patients demonstrated a highly significant positive correlation between FT4 (Abbott AxSYM) and RhF concentrations. Discrepant, apparently increased FT4 with a normal result for thyroid-stimulating hormone should lead to measurement of the patient's RhF concentration. PMID:9191546

  15. A Preliminary Link between Hydroxylated Metabolites of Polychlorinated Biphenyls and Free Thyroxin in Humans

    Science.gov (United States)

    Dirinck, Eveline; Dirtu, Alin C.; Malarvannan, Govindan; Covaci, Adrian; Jorens, Philippe G.; Van Gaal, Luc F.

    2016-01-01

    Background: Polychlorinated biphenyls (PCBs) and their hydroxylated metabolites (HO-PCBs) interfere with thyroid hormone action both in vitro and in vivo. However, epidemiologic studies on the link between PCB exposure and thyroid function have yielded discordant results, while very few data are available for HO-PCBs. Objectives: Our study aimed at investigating the relationship between clinically available markers of thyroid metabolism and serum levels of both PCBs and HO-PCBs. Subjects and Methods: In a group of 180 subjects, thyroid-stimulating hormone (TSH) and free thyroxin (fT4), 29 PCBs (expressed both in lipid weight and in wet weight) and 18 HO-PCBs were measured in serum. Results: In regression models, adjusted for gender, age, current smoking behavior, BMI and total lipid levels, serum levels of 3HO-PCB118 and 3HO-PCB180, and PCB95lw, PCB99lw and PCB149lw were independent, significant predictors of fT4. A stepwise, multiple regression with gender, age, current smoking behavior, BMI and total lipid levels and all five previously identified significant compounds retained age, BMI, PCB95lw, PCB99lw and 3HO-PCB180 as significant predictors of fT4. TSH levels were not predicted by serum levels of any of the PCBs or HO-PCBs. Conclusions: Our study indicates that in vivo, circulating fT4 levels can be linked to serum levels of several PCBs and hydroxylated PCB metabolites. PMID:27089353

  16. Oral L-thyroxine liquid versus tablet in patients with hypothyroidism without malabsorption: a prospective study.

    Science.gov (United States)

    Fallahi, Poupak; Ferrari, Silvia Martina; Antonelli, Alessandro

    2016-06-01

    No consistent data are present in literature about the effectiveness of levothyroxine (L-T4) liquid formulation in patients without malabsorption. The aim of this study is to compare the effectiveness of L-T4 liquid formulation, with L-T4 tablets, in hypothyroid patients without malabsorption or drug interference. One hundred and fifty two patients were recruited. Patients were switched from the L-T4 therapy in tablets, to liquid L-T4 at the same dosage, 30 min before breakfast. Serum thyrotropic hormone (TSH), free thyroxine (FT4), and free triiodothyronine (FT3) were re-evaluated after 1-3 months (first control) and 5-7 months (second control) from the switch. TSH values significantly declined with respect to the basal value after the switch to liquid L-T4 both at the first control (P < 0.05) and at the second control (P < 0.01); FT4 and FT3 levels were not significantly changed. We show that liquid L-T4 is more effective than L-T4 tablet in controlling TSH levels in hypothyroid patients without malabsorption, gastric disorders, or drug interference. PMID:26721663

  17. Radioimmunoassay of thyroxine and 3,3',5'-triiodothyronine (reverse T3) in human amniotic fluid

    International Nuclear Information System (INIS)

    Measurements of amniotic fluid iodothyronine concentrations may enable antenatal detection of fetal thyroid abnormalities; however, the delineation of normal ranges is complicated by methodological problems associated with strong and highly variable protein-binding, and specificity of antisera. Improved radioimmunoassays of thyroxine (T4) and 3,3',5'-triiodothyronine (reverse T3, rT3) have been developed to overcome these problems. In normal pregnancy, mean rT3 concentrations at <17 weeks, 17-22 weeks and 35-42 weeks gestation were 3.6 nmol/l (n=21), 6.1 nmol/l (n=14) and 0.66 nmol/l (n=39) respectively; corresponding mean T4 concentrations were 2.4 nmol/l, 6.5 nmol/l and 3.6 nmol/l. rT3 concentrations showed a strong positive correlation with T4 concentration in each age range; however, the molar ratio of rT3 : T4 decreased progressively with gestational age, from 1.69 at <17 weeks to 0.19 at 35-42 weeks. In both mid- and late gestation, rT3 and T4 concentrations were strongly correlated with total amniotic fluid protein concentrations. (Auth.)

  18. Nitric Oxide as a Marker for Levo-Thyroxine Therapy in Subclinical Hypothyroid Patients.

    Science.gov (United States)

    Obradovic, Milan; Gluvic, Zoran; Sudar-Milovanovic, Emina; Panic, Anastasija; Trebaljevac, Jovana; Bajic, Vladan; Zarkovic, Milos; Isenovic, Esma R

    2016-01-01

    Subclinical hypothyroidism (SH) is characterized by a mildly elevated concentration of thyroid stimulating hormone (TSH) despite free thyroxine (FT4) and triiodothyronine (FT3) levels within the reference range. Numerous studies revealed SH to be an independent risk factor for cardiovascular disease (CVD), including atherosclerosis, congestive heart failure, coronary heart disease, ischemic heart disease and the associated mortality. The relationship between SH and CVD is well documented, but the molecular mechanism underlying this correlation remain unknown. Endothelial dysfunction has been recognized as an initial step leading to CVD in patients with SH. Changes in lipid profile, inflammation and/or oxidative stress contribute to the endothelial dysfunction in SH. Moreover, the progression of SH is characterized by significantly decreased nitrite and nitrate levels. Recent animal and clinical studies discussed in this review suggest that nitric oxide (NO) levels could be a reliable biomarker for cardiovascular risk in SH. Understanding the regulation of NO production by thyroid hormone may provide novel and useful knowledge regarding how endothelial dysfunction in SH is linked with CVD and help us to uncover new treatments for SH. We suggest that serum NO level may be an indicator for the introduction and dosage of levothyroxine (LT4) replacement therapy in SH patients. Future studies should focus on understanding the molecular mechanisms underlying the effects of NO in physiological as well as in pathophysiological conditions such as hypothyroidism and their clinical relevance. PMID:26853795

  19. Radioimmunoassay of thyroxine and triiodothyronine in urine using extraction and separation on Sephadex columns

    International Nuclear Information System (INIS)

    Radioimmunological methods for the determination of thyroxine (T4) and triiodothyronine (T3) in urine have been developed. The methods are based on trapping of T4 and T3 from unextracted urine, followed by separation between free and antibody bound hormone on the same Sephadex column. The T4 method has been compared to a competitive protein binding (CPB) assay using ethyl acetate extraction. The methods are evaluated in sixty-seven euthyroid controls, twenty-four hyperthyroid and seven hypothyroid patients. In the T4 RIA detection limit was 3.9 pg, intra-assay coefficient of variation (cv) was 5.2% and inter-assay cv was 6.9%. In the T3 RIA detection limit was 7.2 pg, intra-assay cv 3.9% and inter-assay cv 10.8%. Recovery of added amounts of hormones and serial dilutions gave satisfactory results. The CPB assay was found unreliable with unspecific and false high values. In euthyroid controls 24 h urinary T4 excretion as measured by RIA was 1.8+-0.5 nmol, and urinary T3 excretion was 0.7+-0.3 nmol. T4 and T3 excretion was greatly elevated in hyperthyroid patients and decreased in hypothyroidism. (Auth.)

  20. Solid Phase Radioimmunoassay for Measuring Serum Triiodothyronine and Thyroxine using Different Preparations of Their Labeled Hormones

    International Nuclear Information System (INIS)

    The goal of the present work was oriented to prepare stable polystyrene coated tubes for direct radioimmunoassay (RIA) of triiodothyronine (T3) and thyroxine (T4) in human serum or plasma. Coating process was performed using sheep polyclonal antisera specific for each of T3 and T4. The stability study showed that these tubes could be stored for up to one year at 4 degree without any appreciable reduction in their binding. The preparations of 25I-T3 and 125I-T4 were carried out by two different methods [chloramine-T(Ch-T) and iodogen] . It was found that Ch-T method gave approximately the same results as iodogen method. Twenty five samples of different thyroid status were assayed for T3 and T4 using the present systems and with commerically available kits (coated tubes, DPC). The statistical analysis revealed good correlations between the results from the present systems using T3 and T4 tracers prepared by Ch-T and iodogen methods and The DPC kits. This may be extremely helpful in diagnosis and proper management of thyroid dysfunctions

  1. Screening for neonatal hypothyroidism by thyroxine and thyrotrophin radioimmunoassays using dried blood samples on filter paper

    International Nuclear Information System (INIS)

    A routine and automated methodology for thyroxine (T4) and thyrotrophin (TSH) radioimmunoassay (RIA) using dried blood samples on filter paper is described. T4-RIA was performed on one single dot (5 mm diameter equivalent to 4 μl of serum) while two dots were necessary for TSH-RIA. Reference filter papers were introduced in each assay for quality control. In a preliminary study on 4,155 neonates, samples generally obtained between the 5th-7th day gave a mean 'dot-T4' of 97.95 +- 36.04 nmol/l and a mean 'dot-TSH' of 10.19 mU/l +- 8.25, corresponding to 2.47 mU/l of serum. Within an 18-month period (November 1976 - April 1978), a total of 16,522 neonates have been screened allowing detection of three cases of congenital hypothyroidism (incidence 1:5507), two cases of congenitally low TBG and thirty-three cases of transient hypothyroidism. (author)

  2. Free thyroxin measured in dried blood spots from normal, low-birth-weight, and hypothyroid neonates.

    Science.gov (United States)

    Lemonnier, F; Masson, J; Laroche, D; Travert, J; Travert, G

    1991-12-01

    We have adapted a new radioimmunoassay for free thyroxin (FT4) measurement in dried blood spots for use in neonatal screening for hypothyroidism. The method is easy, fast, and cheap. Within-assay and between-assay CVs are respectively 9.6% and 13.2%. In 997 neonates three days postpartum with normal thyrotropin concentrations, the mean FT4 concentration was 27.2 pmol/L (SD 7.3 pmol/L). There was no significant difference in mean FT4 concentration between boys and girls. FT4 concentrations increased linearly with birth weight or with gestational age, as expressed by multiple linear regression: FT4 (pmol/L) = 0.0016 birth weight (g) + 0.6931 gestational age (weeks) - 4.8772. Only gestational age significantly affected the FT4 value. For five hypothyroid infants tested on day three postpartum, FT4 values were all below the 1st percentile of values from healthy neonates. Thus, when the neonatal concentration of thyrotropin is above normal, FT4 measured in the same sample can provide a reliable earlier diagnosis of hypothyroidism. PMID:1764786

  3. Acute redistribution of thyroxine after the administration of univalent anions, salicylate, theophylline and barbiturates in rats

    International Nuclear Information System (INIS)

    Rats were injected with [125I]L-thyroxine (T4) ip 16 h before the experiment and samples of blood were frequently taken from polyethylene tubing inserted into the femoral artery in anaesthetized and heparin-injected animals. In each sample of plasma T4 counts per ml were estimated with the acid of paper chromatography. Rapid decrease of circulating T4 level was found at 20 min after iv injection of thiocyanate, iodide, fluoroborate, theophylline and salicylate and a dose-response relationship was established between such a decrease and the administered dose of salicylate (5-160 mg/400 g b.w.). A similar decrease was observed at 60 min after ip injection of some general anaesthetics or tranquilizers. An increase of T4 fractional disposal rate was found between 120 and 480 min after the administration of some of the anaesthetics and this effect was abolished by the administration of thiocyanate. It was concluded that there are two different effects of drugs on the circulating T4 level: 1. the immediate effect resulting apparently from a decreased plasma protein binding. 2. the prolonged effect which presumably results from the increased turnover of T4 by peripheral tissues, the metabolic basis of which remains unexplained. (author)

  4. A Preliminary Link between Hydroxylated Metabolites of Polychlorinated Biphenyls and Free Thyroxin in Humans

    Directory of Open Access Journals (Sweden)

    Eveline Dirinck

    2016-04-01

    Full Text Available Background: Polychlorinated biphenyls (PCBs and their hydroxylated metabolites (HO-PCBs interfere with thyroid hormone action both in vitro and in vivo. However, epidemiologic studies on the link between PCB exposure and thyroid function have yielded discordant results, while very few data are available for HO-PCBs. Objectives: Our study aimed at investigating the relationship between clinically available markers of thyroid metabolism and serum levels of both PCBs and HO-PCBs. Subjects and Methods: In a group of 180 subjects, thyroid-stimulating hormone (TSH and free thyroxin (fT4, 29 PCBs (expressed both in lipid weight and in wet weight and 18 HO-PCBs were measured in serum. Results: In regression models, adjusted for gender, age, current smoking behavior, BMI and total lipid levels, serum levels of 3HO-PCB118 and 3HO-PCB180, and PCB95lw, PCB99lw and PCB149lw were independent, significant predictors of fT4. A stepwise, multiple regression with gender, age, current smoking behavior, BMI and total lipid levels and all five previously identified significant compounds retained age, BMI, PCB95lw, PCB99lw and 3HO-PCB180 as significant predictors of fT4. TSH levels were not predicted by serum levels of any of the PCBs or HO-PCBs. Conclusions: Our study indicates that in vivo, circulating fT4 levels can be linked to serum levels of several PCBs and hydroxylated PCB metabolites.

  5. Body fat, abdominal fat and body fat distribution related to cardiovascular risk factors in prepubertal children

    DEFF Research Database (Denmark)

    Dencker, Magnus; Wollmer, Per; Karlsson, Magnus K;

    2012-01-01

    measured by Dual-Energy X-Ray Absorptiometry. TBF was expressed as a percentage of body weight (BF%). Body fat distribution was calculated as AFM/TBF. Maximal oxygen uptake (VO(2PEAK) ), systolic and diastolic blood pressure (SBP, DBP), and resting heart rate (RHR) were measured. Mean arterial pressure......Aim:  We analysed whether total body fat (TBF), abdominal fat and body fat distribution are associated with higher composite risk factor scores for cardiovascular disease (CVD) in young children. Methods:  Cross-sectional study of 238 children aged 8-11 years. TBF and abdominal fat mass (AFM) were...

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

    Science.gov (United States)

    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. PMID:25150689

  7. Body fat, abdominal fat and body fat distribution related to VO(2PEAK) in young children

    DEFF Research Database (Denmark)

    Dencker, Magnus; Wollmer, Per; Karlsson, Magnus K;

    2011-01-01

    percentage of body mass (BF%) and body fat distribution as AFM/TBF. VO(2PEAK) was assessed by indirect calorimetry during maximal exercise test. Results. Significant relationships existed between body fat measurements and VO(2PEAK) in both boys and girls, with Pearson correlation coefficients for absolute......Abstract Objective. Aerobic fitness, defined as maximum oxygen uptake (VO(2PEAK)), and body fat measurements represent two known risk factors for disease. The purpose of this study was to investigate the relationship between VO(2PEAK) and body fat measurements in young children at a population......-based level. Methods. Cross-sectional study of 225 children (128 boys and 97 girls) aged 8-11 years, recruited from a population-based cohort. Total lean body mass (LBM), total fat mass (TBF), and abdominal fat mass (AFM) were measured by dual-energy x-ray absorptiometry. Body fat was also calculated as a...

  8. Thioesterase superfamily member 1 suppresses cold thermogenesis by limiting the oxidation of lipid droplet-derived fatty acids in brown adipose tissue

    Directory of Open Access Journals (Sweden)

    Kosuke Okada

    2016-05-01

    Conclusions: These results show that Them1 may act as a break on uncontrolled heat production and limit the extent of energy expenditure. Pharmacologic inhibition of Them1 could provide a targeted strategy for the management of metabolic disorders via activation of brown fat.

  9. Severe fat embolism in perioperative abdominal liposuction and fat grafting

    OpenAIRE

    Rodrigo de Lima e Souza; Bruno Tavares Apgaua; João Daniel Milhomens; Francisco Tadeu Motta Albuquerque; Luiz Antônio Carneiro; Márcio Henrique Mendes; Tiago Carvalho Garcia; Clerisson Paiva; Felipe Ladeia; Deiler Célio Jeunon

    2016-01-01

    ABSTRACT BACKGROUND AND OBJECTIVES: Fat embolism syndrome may occur in patients suffering from multiple trauma (long bone fractures) or plastic surgery (liposuction), compromising the circulatory, respiratory and/or central nervous systems. This report shows the evolution of severe fat embolism syndrome after liposuction and fat grafting. CASE REPORT: SSS, 42 years old, ASA 1, no risk factors for thrombosis, candidate for abdominal liposuction and breast implant prosthesis. Subjected to b...

  10. Facial Fat Necrosis Following Autologous Fat Transfer and its Management

    OpenAIRE

    Sweta Rai; Marsland, Alexander M; Vishal Madan

    2014-01-01

    Autologous fat transfer (AFT) is an increasingly popular cosmetic procedure practiced by dermatologic surgeons worldwide. As this is an office based procedure performed under local or tumescent anaesthesia with fat transferred within the same individual and limited associated down time its is considered relatively safe and risk free in the cosmetic surgery arena. We describe a case of AFT related fat necrosis causing significant facial dysmorphia and psychosocial distress. We also discuss the...

  11. Carnitine Palmitoyltransferase 1 Increases Lipolysis, UCP1 Protein Expression and Mitochondrial Activity in Brown Adipocytes

    Science.gov (United States)

    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

  12. Control and physiological determinants of sympathetically-mediated brown adipose tissue thermogenesis

    Directory of Open Access Journals (Sweden)

    Denis eRichard

    2012-02-01

    Full Text Available Brown adipose tissue (BAT represents a remarkable heat-producing tissue. The thermogenic potential of BAT is conferred by uncoupling protein 1, a protein found uniquely in the brown adipocytes. The physiological control of BAT activity and capacity is ensured by the sympathetic nervous system (SNS, which densely innervates brown fat depots. SNS-mediated BAT thermogenesis is essentially governed by hypothalamic and brainstem neurons. BAT is not only controlled by the brain thermoregulatory circuits but also by brain energy balance pathways including the very significant brain melanocortin system, which speaks in favor of the genuine involvement of SNS-mediated BAT thermogenesis in energy homeostasis. The use of positron emission tomography/computed tomography (PET/CT scanning has further revealed the presence of well-defined BAT depots in the cervical, clavicular, and paraspinal areas in adult humans. The prevalence of these depots was reported to be higher in subjects exposed to low temperature and was also higher in women than men. Moreover, the prevalence of BAT was shown to decrease with age and body fat mass, which suggests that BAT could not only be involved in cold-induced non shivering thermogenesis but also in the energy balance regulation and obesity in humans. This short review summarizes recent progress made in our understanding of the control of SNS-mediated BAT thermogenesis and of the determinants of BAT prevalence or detection in humans.

  13. AHNAK deficiency promotes browning and lipolysis in mice via increased responsiveness to β-adrenergic signalling.

    Science.gov (United States)

    Shin, Jae Hoon; Lee, Seo Hyun; Kim, Yo Na; Kim, Il Yong; Kim, Youn Ju; Kyeong, Dong Soo; Lim, Hee Jung; Cho, Soo Young; Choi, Junhee; Wi, Young Jin; Choi, Jae-Hoon; Yoon, Yeo Sung; Bae, Yun Soo; Seong, Je Kyung

    2016-01-01

    In adipose tissue, agonists of the β3-adrenergic receptor (ADRB3) regulate lipolysis, lipid oxidation, and thermogenesis. The deficiency in the thermogenesis induced by neuroblast differentiation-associated protein AHNAK in white adipose tissue (WAT) of mice fed a high-fat diet suggests that AHNAK may stimulate energy expenditure via development of beige fat. Here, we report that AHNAK deficiency promoted browning and thermogenic gene expression in WAT but not in brown adipose tissue of mice stimulated with the ADRB3 agonist CL-316243. Consistent with the increased thermogenesis, Ahnak(-/-) mice exhibited an increase in energy expenditure, accompanied by elevated mitochondrial biogenesis in WAT depots in response to CL-316243. Additionally, AHNAK-deficient WAT contained more eosinophils and higher levels of type 2 cytokines (IL-4/IL-13) to promote browning of WAT in response to CL-316243. This was associated with enhanced sympathetic tone in the WAT via upregulation of adrb3 and tyrosine hydroxylase (TH) in response to β-adrenergic activation. CL-316243 activated PKA signalling and enhanced lipolysis, as evidenced by increased phosphorylation of hormone-sensitive lipase and release of free glycerol in Ahnak(-/-) mice compared to wild-type mice. Overall, these findings suggest an important role of AHNAK in the regulation of thermogenesis and lipolysis in WAT via β-adrenergic signalling. PMID:26987950

  14. Direct effects of leptin on brown and white adipose tissue.

    Science.gov (United States)

    Siegrist-Kaiser, C A; Pauli, V; Juge-Aubry, C E; Boss, O; Pernin, A; Chin, W W; Cusin, I; Rohner-Jeanrenaud, F; Burger, A G; Zapf, J; Meier, C A

    1997-01-01

    Leptin is thought to exert its actions on energy homeostasis through the long form of the leptin receptor (OB-Rb), which is present in the hypothalamus and in certain peripheral organs, including adipose tissue. In this study, we examined whether leptin has direct effects on the function of brown and white adipose tissue (BAT and WAT, respectively) at the metabolic and molecular levels. The chronic peripheral intravenous administration of leptin in vivo for 4 d resulted in a 1.6-fold increase in the in vivo glucose utilization index of BAT, whereas no significant change was found after intracerebroventricular administration compared with pair-fed control rats, compatible with a direct effect of leptin on BAT. The effect of leptin on WAT fat pads from lean Zucker Fa/ fa rats was assessed ex vivo, where a 9- and 16-fold increase in the rate of lipolysis was observed after 2 h of exposure to 0.1 and 10 nM leptin, respectively. In contrast, no increase in lipolysis was observed in the fat pads from obese fa/fa rats, which harbor an inactivating mutation in the OB-Rb. At the level of gene expression, leptin treatment for 24 h increased malic enzyme and lipoprotein lipase RNA 1.8+/-0.17 and 1.9+/-0.14-fold, respectively, while aP2 mRNA levels were unaltered in primary cultures of brown adipocytes from lean Fa/fa rats. Importantly, however, no significant effect of leptin was observed on these genes in brown adipocytes from obese fa/fa animals. The presence of OB-Rb receptors in adipose tissue was substantiated by the detection of its transcripts by RT-PCR, and leptin treatment in vivo and in vitro activated the specific STATs implicated in the signaling pathway of the OB-Rb. Taken together, our data strongly suggest that leptin has direct effects on BAT and WAT, resulting in the activation of the Jak/STAT pathway and the increased expression of certain target genes, which may partially account for the observed increase in glucose utilization and lipolysis in leptin

  15. Facial fat necrosis following autologous fat transfer and its management

    Directory of Open Access Journals (Sweden)

    Sweta Rai

    2014-01-01

    Full Text Available Autologous fat transfer (AFT is an increasingly popular cosmetic procedure practiced by dermatologic surgeons worldwide. As this is an office based procedure performed under local or tumescent anaesthesia with fat transferred within the same individual and limited associated down time its is considered relatively safe and risk free in the cosmetic surgery arena. We describe a case of AFT related fat necrosis causing significant facial dysmorphia and psychosocial distress. We also discuss the benefits and risks of AFT highlighting common causes of fat graft failure.

  16. The influence of a thyroxine supplemented diet on selected hepatic redox equilibrium markers, liver morphology and the serum lipid profile in rats treated with doxorubicin 

    Directory of Open Access Journals (Sweden)

    Agnieszka Korga

    2013-03-01

    Full Text Available Introduction: Cytotoxicity of doxorubicin (DOX – an anticancer drug, mostly results from reactive oxygen species (ROS generation. Some enzymes catalyzing this process and enzymes of antioxidant defense are regulated by iodothyronine hormones. Thus, disorders in iodothyronine hormone status may affect doxorubicin-induced redox imbalance and anabolic/catabolic disorders. The aim of this study was to evaluate the influence of doxorubicin and thyroxine (T4 associated treatment on liver morphology, markers of oxidative stress and plasma lipid parameters.Materials and methods: Rats were intraperitoneally treated with doxorubicin (1.5 mg/kg once a week for ten weeks. Thyroxine was simultaneously given in drinking water (0.2 or 2.0 mg/l for 14 weeks.Results: There were higher hepatic level of malonyldialdehyde (MDA of all tested groups and at the same time in rats treated with DOX plus T4 lower concentrations of total glutathione compared to controls were observed. Morphology of liver did not show any features of necrosis or steatosis but a decrease of glycogen content in T4 DOX groups compared to DOX treatment was observed. The concomitant administration of a lower dose of thyroxine and doxorubicin decreased triglycerides (TG and increased LDL level compared to the DOX group.Discussion: Thyroxin supplementation caused redox equilibrium disorders and oxidative stress in liver of rats receiving DOX. The study revealed the normalizing influence of thyroxin on glycogen deposits that were observed after doxorubicin treatment. Apart from an adverse impact of thyroxine administration on LDL in rats treated with doxorubicin, a beneficial effect of lower dose of thyroxine on serum TG level was revealed. 

  17. Effectiveness of L-thyroxine treatment on TSH suppression during pregnancy in patients with a history of thyroid carcinoma after total thyroidectomy and radioiodine ablation

    International Nuclear Information System (INIS)

    There are scarce data about the optimal increase of L-thyroxine dose during pregnancy in patients with a history of thyroid carcinoma. The first aim of the study was to find out if routine therapeutic measures enable adequate TSH suppression in pregnancy. The other aim was to find out the optimal dose of L-thyroxine for TSH suppression in pregnant women. In this retrospective observational study, we analysed 36 pregnancies of 32 women with a history of thyroid carcinoma. Before pregnancy, all of them underwent total thyroidectomy and radioiodine ablation of thyroid remnant, and they were on suppressive doses of L-thyroxine. Thyroid function tests were obtained before, during and after pregnancy. Mean L-thyroxine dose before pregnancy, in the first, second and, third trimester and after delivery was 149, 147, 155, 165 and 158 micrograms daily, respectively. TSH concentration remained suppressed in 9 pregnancies, it was within normal range in 22 and elevated in 5 pregnancies. The mean dose of L-thyroxine in patients with suppressed TSH before pregnancy, in the first, second and, third trimester and after delivery was 154, 154, 164, 160 and 161 micrograms daily, respectively. When the dose had to be changed, the mean increase of the dose was 31.5 micrograms daily. The range of changes in TSH concentration during pregnancy in the patients who have been on suppressive L-thyroxine therapy before conception is quite wide. TSH was adequately suppressed in only 25% of pregnancies. The dose of L-thyroxine in patients with suppressed TSH in the first, second and third trimester was 154, 164 and 160 micrograms daily, respectively

  18. Brown dwarf disks with ALMA

    Energy Technology Data Exchange (ETDEWEB)

    Ricci, L.; Isella, A. [Department of Astronomy, California Institute of Technology, MC 249-17, Pasadena, CA 91125 (United States); Testi, L.; De Gregorio-Monsalvo, I. [European Southern Observatory, Karl-Schwarzschild-Strasse 2, D-85748 Garching (Germany); Natta, A. [INAF-Osservatorio Astrofisico di Arcetri, Largo E. Fermi 5, I-50125 Firenze (Italy); Scholz, A., E-mail: lricci@astro.caltech.edu [School of Cosmic Physics, Dublin Institute for Advanced Studies, 31 Fitzwilliam Place, Dublin 2 (Ireland)

    2014-08-10

    We present Atacama Large Millimeter/submillimeter Array continuum and spectral line data at 0.89 mm and 3.2 mm for three disks surrounding young brown dwarfs and very low mass stars in the Taurus star forming region. Dust thermal emission is detected and spatially resolved for all the three disks, while CO(J = 3-2) emission is seen in two disks. We analyze the continuum visibilities and constrain the disks' physical structure in dust. The results of our analysis show that the disks are relatively large; the smallest one has an outer radius of about 70 AU. The inferred disk radii, radial profiles of the dust surface density, and disk to central object mass ratios lie within the ranges found for disks around more massive young stars. We derive from our observations the wavelength dependence of the millimeter dust opacity. In all the three disks, data are consistent with the presence of grains with at least millimeter sizes, as also found for disks around young stars, and confirm that the early stages of the solid growth toward planetesimals occur also around very low-mass objects. We discuss the implications of our findings on models of solids evolution in protoplanetary disks, the main mechanisms proposed for the formation of brown dwarfs and very low-mass stars, as well as the potential of finding rocky and giant planets around very low-mass objects.

  19. Dietary Fats and Metabolic Syndrome

    Directory of Open Access Journals (Sweden)

    Danijela Ristic-Medic

    2013-12-01

    Full Text Available The quantity and quality of fats consumed in the diet can have important effects on prevention and/or improvement clustering metabolic abnormalities of the metabolic syndrome. Fatty acids as food ingredients regulate cholesterol homeostasis and concentrations of blood lipoproteins, and affect the levels of other cardiometabolic risk factors, such as blood pressure, haemostasis, and body weight, through various mechanisms. There is convincing evidence that exchanging dietary saturated fat with monounsaturated fat produces beneficial effects on metabolic control, i.a. it lowers LDL-cholesterol concentrations, improves the postprandial lipid profile and lowers the blood pressure. Serum fatty acid composition mainly reflects dietary fat intake, but also endogenous fatty acid synthesis catalyzed by desaturases. Furthermore, high fat intake and serum fatty acid profile may influence the progression of obesity and insulin sensitivity. This review highlights current dietary guidance of fats quality recommendation in health and cardio metabolic risk.

  20. Fat embolism syndrome.

    Science.gov (United States)

    Williams, A G; Mettler, F A; Christie, J H; Gordon, R E

    1986-07-01

    The fat embolism syndrome is clinically evident in approximately 0.5-2.0% of patients with long bone fractures. The clinical signs and symptoms are evident in 60% of patients within 24 hours and 85% of patients within 48 hours after trauma. A patient is reported who complained of dyspnea and hemoptysis approximately 72 hours after sustaining a fracture to the distal tibia and fibula. Radionuclide ventilation/perfusion imaging was obtained to rule out pulmonary thromboemboli. Perfusion imaging demonstrated the characteristic diffuse, subsegmental ("mottled") appearance of fatty emboli to the lung. PMID:3731649

  1. Isolation of glycoproteins from brown algae.

    OpenAIRE

    Surendraraj, Alagarsamy; Farvin Koduvayur Habeebullah , Sabeena; Jacobsen, Charlotte

    2015-01-01

    The present invention relates to a novel process for the isolation of unique anti-oxidative glycoproteins from the pH precipitated fractions of enzymatic extracts of brown algae. Two brown seaweeds viz, Fucus serratus and Fucus vesiculosus were hydrolysed by using 3 enzymes viz, Alcalase, Viscozyme and Termamyl and the glycoproteins were isolated from these enzyme extracts.

  2. The Indirectness of Young Goodman Brown

    Institute of Scientific and Technical Information of China (English)

    袁臣

    2010-01-01

    Young Goodman Brown is one the best short fictions written by Nathaniel Hawthorne in 1835. The indirectness of the Young Goodman Brown can be seen from the produce, narration and the characteristics of the short fiction. The indirectness of expression or description leaves enough space for readers to understand the theme of the short fiction by themselves.

  3. Microlensing Binaries with Candidate Brown Dwarf Companions

    DEFF Research Database (Denmark)

    Shin, I.-G; Han, C.; Gould, A.;

    2012-01-01

    Brown dwarfs are important objects because they may provide a missing link between stars and planets, two populations that have dramatically different formation histories. In this paper, we present the candidate binaries with brown dwarf companions that are found by analyzing binary microlensing ...

  4. Isolation of glycoproteins from brown algae

    DEFF Research Database (Denmark)

    2015-01-01

    The present invention relates to a novel process for the isolation of unique anti-oxidative glycoproteins from the pH precipitated fractions of enzymatic extracts of brown algae. Two brown seaweeds viz, Fucus serratus and Fucus vesiculosus were hydrolysed by using 3 enzymes viz, Alcalase, Viscozyme...

  5. Influence of the Brown Marine Algae on the Physicochemical and Sensory Characteristcs of the Sausages

    Directory of Open Access Journals (Sweden)

    Claudiu Dan Sălăgean

    2015-11-01

    Full Text Available  The aim of this study was to asses the influence of the brown algae on the quality in manufacturing of a certain halfsmoked sausages assortment.  Exploiting the natural plant resources as well as reducing the animal fat in the finished product by replacing it with proteins, fibers and minerals (provided by the brown marine algae were also intended. Two technological variants with different ratios of algae (V1-10% respectively V2-15% from those 25% of fat (the remaining of 75% beeing represented, in each case, by beef were experienced and compared with the control sample (VM, without algae, 75% beef and 25% fat. The finished products were analyzed in terms of organoleptic and physicochemical, in different stages of storage, at 24 hours after obtaining and seven days of storage at 10 to 12 degrees. The correlations between investigated quality parameters and the ratios of algae were also established. The physicochemical analysis highlighted the highest values regarding the protein, moisture, sodium chloride and the lowest fat content values in the case of the V2 variant compared to the V1 and VM variants. Furthermore, an increase in protein, fat, sodium chloride and a decrease of the moisture content have been found in all variants observed during the storage. The shelf life of the product was not negatively affected by the addition of algae due to their antimicrobial activity. The addition of algae in combination with beef components led to obtaining a higher quality product with functional characteristics.

  6. Isoforms of thyroxine-binding globulin as a model for molecular epidemiology of human cancer risk

    International Nuclear Information System (INIS)

    The novel field of molecular epidemiology of human cancer risk has added a new branch to classical epidemiology by providing a direct link between human cancer and carcinogen exposure. It was estimated that about 80% of cancers are due to environmental factors. The blood proteins are almost certainly targets for modification in human cancer, and their identification and characterization will be of primary importance in the development of the new and rapidly evolving field of molecular epidemiology. Among blood proteins that are altered in human cancer, TBG occupies a special place because the level of human blood TBG is the most sensitive to intensification of biosynthesis and proliferation processes in organisms in different types of cancer. The increase of TBG concentration in cancer can be result from both activation of TBG biosynthesis in liver or altering of post translation glycosylation that prolongs protein survival time. The molecular basis for the change in the properties of TBG in cancer is unknown. These distinctive changes could have important consequences for the function of TBG in cancer and may help to develop more precise markers for monitoring pathological progression in this disease. Considerable variability and subtlety can occur in the carbohydrate composition and structure of serum glycoproteins in disease. This can be either as a major change, such as an increase in the number of oligosaccharide branches at a particular glycosylation site or as a minor change such as the addition of an extra fucose or sialic acid residue. Increased fucosylation has also been reported for transferrin and alpha-fetoprotein in liver cancer; thyroglobulin in thyroid cancer, IgG in myeloma, haptoglobin in ovarian cancer. The last own studies have shown that in clinically healthy teenagers born in Khojniki (137 Cs 185-555 kBq/m), we have found an unusual thyroid profile exhibiting increased levels of total triiodothyronine (T3), total thyroxine (T4), and thyroxine

  7. [Posttraumatic fat embolism].

    Science.gov (United States)

    Bouffard, Y; Guillaume, C; Perrot, D; Delafosse, B; Motin, J

    1984-01-01

    Between 1977 and 1982, fifty cases of post-traumatic fat embolism were treated in a general intensive care unit. Average age of patients was 25.5 +/- 13 years; there was no male majority. Mean free interval was 39 +/- 27 h. 12 cases (24%) had single fractures and 38 (76%) multiple fractures. Forty-four patients had a fractured femur. Thirty-two patients presented the complete clinical syndrome with general, respiratory, neurological and cutaneous signs. Thrombocytopaenia and hypocholesterolaemia were the biological signs most often seen. In forty-four patients, orthopaedic treatment consisted of immediate immobilization, usually with traction. Twenty-six patients were reoperated on: intramedullary nail for twenty patients, plate for the other six. Fat embolism appeared in spite of surgery in six cases; it worsened after surgery in six others. Seven patients had per- or postanaesthetic problems. Fourteen per cent of patients died. The decrease in mortality was mainly due to an improvement in mechanical ventilation techniques. Early surgical fixation remained the rule if there was no serious respiratory distress or haemodynamic instability, although it did not seem to change the mortality rate in this group of patients. PMID:6497076

  8. A possible mechanism for the decrease in serum thyroxine level by phenobarbital in rodents

    International Nuclear Information System (INIS)

    Effects of phenobarbital (PB) on the levels of serum thyroid hormones such as total thyroxine (T4) and triiodothyronine were examined in male mice, hamsters, rats, and guinea pigs. One day after the final administration of PB (80 mg/kg, intraperitoneal, once daily for 4 days), significant decreases in the levels of the serum total T4 and free T4 occurred in mice, hamsters, and rats, while a significant decrease in the level of serum triiodothyronine was observed in hamsters and rats among the animals examined. In addition, a significant decrease in the level of serum thyroid-stimulating hormone was observed in only hamsters among the rodents examined. Significant increases in the level and activity of hepatic T4-UDP-glucuronosyltransferase (UGT1A) after the PB administration occurred in mice, hamsters, and rats, while the increase in the amount of biliary [125I]T4-glucuronide after an intravenous injection of [125I]T4 to the PB-pretreated animals occurred only in rats. In mice, rats, and hamsters, but not guinea pigs, PB pretreatment promoted the clearance of [125I]T4 from the serum, led to a significant increase in the steady-state distribution volumes of [125I]T4, and raised the concentration ratio (Kp value) of the liver to serum and the liver distribution of [125I]T4. The present findings indicate that the PB-mediated decreases in the serum T4 level in mice, hamsters, and rats, but not guinea pigs, occur mainly through an increase in the accumulation level of T4 in the liver.

  9. Evaluation of L-thyroxine replacement therapy in children with congenital hypothyroidism.

    Science.gov (United States)

    Chiovato, L; Giusti, L; Tonacchera, M; Ciampi, M; Mammoli, C; Lippi, F; Lapi, P; Bargagna, S; Dini, P; Ferretti, G

    1991-12-01

    The outcome of L-thyroxine (L-T4) replacement therapy in children with congenital hypothyroidism (CH) remains to be completely evaluated. In this paper the overall pattern of response to L-T4 replacement therapy was studied in a group of 19 children with CH diagnosed by neonatal screening (10 with hypoplastic/aplastic thyroid disease, group H/A; 9 with gland ectopy, group E) who were followed-up for 60 +/- 27 months (mean +/- SD). With 1 exception serum T4 at diagnosis was greater than 2 micrograms/dl in children of group E and less than 2 micrograms/dl in those of group H/A. The initial dose of L-T4 (8-10 micrograms/kg BW/day) was modified in relation to age and weight in order to maintain serum TSH less than or equal to 5 microU/ml and FT3 in the normal range. A general inverse correlation between serum TSH and FT4 or FT3 concentrations was found, and the mean levels of serum FT4 and FT3 were significantly higher according to the following order of TSH results: low TSH (0-0.5 microU/ml) greater than normal (greater than 0.5-5 microU/ml) greater than elevated TSH (greater than 5 microU/ml). TSH levels less than or equal to 5 microU/ml were associated with FT4 values in the upper half of the normal range (54% of observations) or even higher (46%). Elevation of serum FT4 alone with FT3 values in the normal range did not result in clinical thyrotoxicosis, alteration of growth or premature craniosynostosis.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:1806614

  10. Thyroxine differentially modulates the peripheral clock: lessons from the human hair follicle.

    Directory of Open Access Journals (Sweden)

    Jonathan A Hardman

    Full Text Available The human hair follicle (HF exhibits peripheral clock activity, with knock-down of clock genes (BMAL1 and PER1 prolonging active hair growth (anagen and increasing pigmentation. Similarly, thyroid hormones prolong anagen and stimulate pigmentation in cultured human HFs. In addition they are recognized as key regulators of the central clock that controls circadian rhythmicity. Therefore, we asked whether thyroxine (T4 also influences peripheral clock activity in the human HF. Over 24 hours we found a significant reduction in protein levels of BMAL1 and PER1, with their transcript levels also decreasing significantly. Furthermore, while all clock genes maintained their rhythmicity in both the control and T4 treated HFs, there was a significant reduction in the amplitude of BMAL1 and PER1 in T4 (100 nM treated HFs. Accompanying this, cell-cycle progression marker Cyclin D1 was also assessed appearing to show an induced circadian rhythmicity by T4 however, this was not significant. Contrary to short term cultures, after 6 days, transcript and/or protein levels of all core clock genes (BMAL1, PER1, clock, CRY1, CRY2 were up-regulated in T4 treated HFs. BMAL1 and PER1 mRNA was also up-regulated in the HF bulge, the location of HF epithelial stem cells. Together this provides the first direct evidence that T4 modulates the expression of the peripheral molecular clock. Thus, patients with thyroid dysfunction may also show a disordered peripheral clock, which raises the possibility that short term, pulsatile treatment with T4 might permit one to modulate circadian activity in peripheral tissues as a target to treat clock-related disease.

  11. Measurement of thyroid hormones (thyroxine, T4; triiodothyronine, T3) in captive nondomestic felids.

    Science.gov (United States)

    Rodini, Débora Cattaruzzi; Felippe, Erika Cristiane Gutierrez; Oliveira, Cláudio Alvarenga

    2007-03-01

    The aim of this research was to obtain basic values for the evaluation of thyroid function in nondomestic felids. Serum thyroid hormone concentrations (thyroxine, T4; triiodothyronine, T3) were measured by radioimmunoassay in 145 cats, representing nine species of captive nondomestic felids: jaguar (Panthera onca), n = 49; puma (Puma concolor), n = 10; ocelot (Leopardus pardalis), n = 22; oncilla (Leopardus tigrinus), n = 12; geoffroy (Oncifelis geoffroyi), n = 4; jaguarundi (Herpailurus yaguarondi), n = 8; margay (Leopardus wiedii), n = 7; lion (Panthera leo), n = 26; and tiger (Panthera tigris), n = 7. For each species, mean +/- SEM of T3 and T4, respectively, were as follows: jaguar, 0.56 +/- 0.03 and 9.7 +/- 0.8 ng/ml; puma, 0.67 +/- 0.04 and 11.2 +/- 1.2 ng/ml; ocelot, 0.48 +/- 0.03 and 13.8 +/- 1.5 ng/ml; oncilla, 0.43 +/- 0.03 and 10.0 +/- 1.6 ng/ml; geoffroy, 0.44 +/- 0.04 and 8.0 +/- 0.16 ng/ml; jaguarundi, 0.7 +/- 0.03 and 5.0 +/- 1.0 ng/ml; margay, 0.48 +/- 0.04 and 12.2 +/- 2.3 ng/ml; lion, 0.43 +/- 0.02 and 5.7 +/- 2.6 ng/ml; and tiger, 0.66 +/- 0.03 and 12.6 +/- 0.9 ng/ml. Within species, T3 and T4 concentrations did not differ (P > 0.05) between males and females. PMID:17469287

  12. Effects of thyroxine on L-cysteine desulfuration in mouse liver.

    Directory of Open Access Journals (Sweden)

    Wróbel M

    2000-02-01

    Full Text Available The effect of exogenous thyroxine (T4 administration on the activity of rhodanese, cystathionase, and 3-mercaptopyruvate sulfurtransferase (MPST in the mitochondrial and cytosolic fractions of mouse liver was investigated. Three groups of mice were treated for 6 consecutive days with subcutaneous injections of T4 (50 micrograms, 100 micrograms, and 250 micrograms per 100 g of body wt, respectively. The other 3 groups were given 100 micrograms of T4 per 100 g of body wt for 1, 2, or 3 days. The dose of 100 micrograms T4 per 100 g of body wt given for 6 days exerted the strongest effect on the activity of all of the investigated enzymes. In comparison to the control, rhodanese activity diminished in the mitochondrial fraction by 40% (P < 0.05, cystathionase activity diminished in the cytosolic fraction by 15% (P < 0.05, and MPST activity in the mitochondrial fraction was reduced by 34% (P < 0.05, whereas cytosolic MPST activity was unaltered. Simultaneously, in the liver homogenate, elevated levels of ATP and sulfate were observed after 6 days of T4 administration. Thus, the present results seem to suggest that in the mouse liver, after 6 days of administration of 100 micrograms T4 per 100 g of body wt, the desulfuration metabolism of L-cysteine is diminished, which is probably accompanied by an increase in oxidative L-cysteine metabolism. The dose of 100 micrograms per 100 g of body wt administered for a shorter period, and the use of a lower dosage (50 micrograms T4 per 100 g of body wt for 6 days had a stimulatory effect upon MPST activity level, and an increased level of sulfane sulfur was observed.

  13. Direct determination of free thyroxine in two simultaneous radioimmunoassays with different test principles

    International Nuclear Information System (INIS)

    Serum FT4 was measured simultaneously by the commercial FT4 kits of Amersham-Buchler and Corning Medical in 4 groups with defined thyroid function as follows: 57 euthroid subjects with and without goitre, 27 patients on T4 supplementation. 12 subjects on oral contraceptives and 26 subclinically hyperthyroid patients. All patients underwent physical examination, thyroid scintigraphy and additional in-vitro tests (total thyroxine T4, total triiodothyronine T3 and TRH/TSH assay). Both assays generally correlated well with the definded thyroid functional status except for the patients on oral contraceptives. Contrary to the FT4-test (Amersham-Buchler) in this group the FT4-test (Corning Medical) produced a significantly increased mean for FT4 as compared to the euthyroid group thus indicating a probably insufficient compensation for high but not necessarily abnormal levels of TBG concentration. Using the FT4-assay (Amersham-Buchler) the normal range of FT4 values of euthyroid subjects from the area of Bamberg with marked iodine deficiency agrees well with recently published results of a multicentre trial thus confirming the assumption of serum FT4 not being strongly dependent on iodine intake. The results of the FT4-test (Corning) showed a wider scatter of normal ranges of FT4 values for all groups and concomitantly reduced discrimination compared to the corresponding simultaneously obtained FT4-test (Amersham-Buchler) results. Though cost and time saving, the commercial radioimmunoassays will require further critical evaluation of normal range validity on larger populations of defined abnormalities will require further critical evaluation of normal range validity on larger populations of defined abnormalities of thyroid function to elucidate inherent deficiencies of the new FT4 methods and of their diagnostic efficiency. (orig./MG)

  14. Prenatal Thyroxine Treatment Disparately Affects Peripheral and Amygdala Thyroid Hormone Levels

    Science.gov (United States)

    Shukla, Pradeep K.; Sittig, Laura J.; Andrus, Brian M.; Schaffer, Daniel J.; Batra, Kanchi K.; Redei, Eva E.

    2009-01-01

    Summary A prenatal hypothyroid state is associated with behavioral abnormalities in adulthood. Wistar–Kyoto (WKY) rats exhibit hypothyroidism and increased depressive and anxiety-like behaviors. Thus, the WKY could illuminate the mechanisms by which the reversal of developmental hypothyroidism in humans and animals results in adult behavioral improvement. We examined the outcome of maternal thyroxine (T4) treatment on thyroid hormone-regulated functions and adult behavior of the WKY offspring. Pregnant WKY dams completed gestation with and without T4 administration and their adult male offspring were tested. Measures included depressive and anxiety-like behaviors, and thyroid hormone (TH) concentrations in both plasma and specific brain regions. In addition, the expression of two proteins affecting thyroid hormone trafficking and metabolism, monocarboxylate transporter 8 (MCT-8) and iodothyronine deiodinase type III (Dio3), and of several behavior-altering molecules, glucocorticoid receptor (GR), prepro-thyrotropin releasing hormone (prepro-TRH) and corticotrophin releasing hormone (CRH), were determined in the hippocampus and amygdala of the offspring. Prenatal T4 treatment of WKYs did not affect adult depressive behavior but increased anxiety-like behavior and decreased plasma levels of THs. In the hippocampus of males treated with T4 in utero, Dio3 and MCT-8 protein levels were increased, while in the amygdala, there were increases of free T4, MCT-8, GR, prepro-TRH protein and CRH mRNA levels. These results show that T4 administration in utero programs adult peripheral and amygdalar thyroid hormone levels divergently, and that the resulting upregulation of anxiety-related genes in the amygdala could be responsible for the exacerbated anxiety-like behavior seen in WKYs after prenatal T4 treatment. PMID:20005050

  15. Contrasting effects of cold acclimation versus obesogenic diets on chemerin gene expression in brown and brite adipose tissues.

    Science.gov (United States)

    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. PMID:25224322

  16. Changes in UCP mRNA expression levels in brown adipose tissue and skeletal muscle after feeding a high-energy diet and relationships with leptin, glucose and PPARgamma

    OpenAIRE

    Margareto, J. (Javier); A. Marti; MARTINEZ, J. A.

    2001-01-01

    Brown adipose tissue and skeletal muscle are known to be important sites for nonshivering thermogenesis. In this context, it is accepted that uncoupling proteins (UCPs) are involved in such process, but little is known about the physiological regulation of these proteins as affected by the intake of a high-energy (cafeteria) diet inducing fat deposition. In this study, the UCP messenger RNA (mRNA) expression in interscapular brown adipose tissue (iBAT) and skeletal muscle was assesse...

  17. MECHANISMS IN ENDOCRINOLOGY: Brown adipose tissue in humans: regulation and metabolic significance.

    Science.gov (United States)

    Thuzar, Moe; Ho, Ken K Y

    2016-07-01

    The recent discovery that functional brown adipose tissue (BAT) persists in adult humans has enkindled a renaissance in metabolic research, with a view of harnessing its thermogenic capacity to combat obesity. This review focuses on the advances in the regulation and the metabolic significance of BAT in humans. BAT activity in humans is stimulated by cold exposure and by several factors such as diet and metabolic hormones. BAT function is regulated at two levels: an acute process involving the stimulation of the intrinsic thermogenic activity of brown adipocytes and a chronic process of growth involving the proliferation of pre-existing brown adipocytes or differentiation to brown adipocytes of adipocytes from specific white adipose tissue depots. BAT activity is reduced in the obese, and its stimulation by cold exposure increases insulin sensitivity and reduces body fat. These observations provide strong evidence that BAT plays a significant role in energy balance in humans and has the potential to be harnessed as a therapeutic target for the management of obesity. PMID:27220620

  18. Control of brown adipose tissue glucose and lipid metabolism by PPARγ

    Directory of Open Access Journals (Sweden)

    William T. Festuccia

    2011-12-01

    Full Text Available Brown adipose tissue (BAT non-shivering thermogenesis impacts energy homeostasis in rodents and humans. Mitochondrial UCP1 in brown fat cells produce heat by dissipating the energy generated by the oxidation of fatty acids and glucose. In addition to thermogenesis and despite its small relative size, sympathetically activated BAT constitutes an important glucose, fatty acid and triacylglycerol-clearing organ, and such function could potentially be used to alleviate dyslipidemias, hyperglycemia and insulin resistance. To date, chronic sympathetic innervation and PPARγ activation are the only recognized inducers of BAT recruitment. Here, we review the major differences between these two inducers of BAT recruitment in the regulation of lipolysis, fatty acid oxidation, lipid uptake and triacylglycerol synthesis, glucose uptake and de novo lipogenesis. Whereas BAT recruitment through sympathetic drive translates into functional thermogenic activity, PPARγ-mediated recruitment is associated with a reduction in sympathetic activity leading to increased lipid storage in brown adipocytes. The promising therapeutic role of brown adipose tissue in the treatment of hypertriglyceridemic and hyperglycaemic conditions are also discussed.

  19. Fat metabolism in formerly obese women

    DEFF Research Database (Denmark)

    Ranneries, C; Bülow, J; Buemann, B;

    1998-01-01

    An impaired fat oxidation has been implicated to play a role in the etiology of obesity, but it is unclear to what extent impaired fat mobilization from adipose tissue or oxidation of fat is responsible. The present study aimed to examine fat mobilization from adipose tissue and whole body fat ox...

  20. Increased plasma clearance rate of thyroxine despite decreased 5'-monodeiodination: study with a peroxisome proliferator in the rat

    Energy Technology Data Exchange (ETDEWEB)

    Kaiser, C.A.; Seydoux, J.; Giacobino, J.P.; Girardier, L.; Burger, A.G.

    1988-03-01

    In euthyroid rats a 17-day treatment with nafenopin, a hypolipidemic agent and peroxisome proliferator, decreased serum total and free T4 concentrations to 32 +/- 5% and 62 +/- 8% (mean +/- SEM; n = 10), respectively, with no change in serum T3 and TSH concentrations. In methimazole-treated rats infused with 3 nmol T4/day/100 g BW, the nafenopin inhibitory effect was not significantly different from that in euthyroid rats. Nafenopin treatment had the following effects on peripheral T4 and T3 metabolism in euthyroid rats. The plasma clearance rate of T4 (PCR), which was measured by Alzet minipump infusion of tracer, was increased 2-fold (1.58 +/- 0.09 vs. 0.82 +/- 0.06 ml/h.100 g BW; P less than 0.001; n = 5), while the PCR of T3 was decreased (37.5 +/- 1.3 vs. 53.8 +/- 1.8; P less than 0.001; n = 5). The fecal clearance rate of radioactivity derived from T4 was increased 2-fold (1.93 +/- 0.10 vs. 0.77 +/- 0.07 ml/h.100 g BW), whereas the urinary clearance rate was not significantly modified. The 5'-deiodinase (5'D) activity, measured by deiodination of labeled rT3, was strongly inhibited in liver and kidney, not modified in brown fat and anterior pituitary, and increased in cerebral cortex. In methimazole-treated rats substituted with isopropyl-diiodothyronine only hepatic 5'D activity was decreased. It is concluded that the decrease in serum total and free T4, without alteration in serum T3 and TSH concentrations, resulting from nafenopin treatment is mainly due to changes in peripheral T4 and T3 metabolism, since it is also observed in T4-substituted animals. The increased PCR of T4 cannot be explained by an increase in deiodination activity, since the major 5'D pathways are inhibited after nafenopin treatment, and the urinary clearance rate is not modified. It can partly be explained by an increase in the fecal clearance rate of T4, which could be due to an increase in glucoronoconjugation.

  1. Increased plasma clearance rate of thyroxine despite decreased 5'-monodeiodination: study with a peroxisome proliferator in the rat

    International Nuclear Information System (INIS)

    In euthyroid rats a 17-day treatment with nafenopin, a hypolipidemic agent and peroxisome proliferator, decreased serum total and free T4 concentrations to 32 +/- 5% and 62 +/- 8% (mean +/- SEM; n = 10), respectively, with no change in serum T3 and TSH concentrations. In methimazole-treated rats infused with 3 nmol T4/day/100 g BW, the nafenopin inhibitory effect was not significantly different from that in euthyroid rats. Nafenopin treatment had the following effects on peripheral T4 and T3 metabolism in euthyroid rats. The plasma clearance rate of T4 (PCR), which was measured by Alzet minipump infusion of tracer, was increased 2-fold (1.58 +/- 0.09 vs. 0.82 +/- 0.06 ml/h.100 g BW; P less than 0.001; n = 5), while the PCR of T3 was decreased (37.5 +/- 1.3 vs. 53.8 +/- 1.8; P less than 0.001; n = 5). The fecal clearance rate of radioactivity derived from T4 was increased 2-fold (1.93 +/- 0.10 vs. 0.77 +/- 0.07 ml/h.100 g BW), whereas the urinary clearance rate was not significantly modified. The 5'-deiodinase (5'D) activity, measured by deiodination of labeled rT3, was strongly inhibited in liver and kidney, not modified in brown fat and anterior pituitary, and increased in cerebral cortex. In methimazole-treated rats substituted with isopropyl-diiodothyronine only hepatic 5'D activity was decreased. It is concluded that the decrease in serum total and free T4, without alteration in serum T3 and TSH concentrations, resulting from nafenopin treatment is mainly due to changes in peripheral T4 and T3 metabolism, since it is also observed in T4-substituted animals. The increased PCR of T4 cannot be explained by an increase in deiodination activity, since the major 5'D pathways are inhibited after nafenopin treatment, and the urinary clearance rate is not modified. It can partly be explained by an increase in the fecal clearance rate of T4, which could be due to an increase in glucoronoconjugation

  2. Quinidine-sensitive K+ channels in the basolateral membrane of embryonic coprodeum epithelium: regulation by aldosterone and thyroxine.

    Science.gov (United States)

    Illek, B; Fischer, H; Clauss, W

    1993-01-01

    Basolateral K+ channels and their regulation during aldosterone- and thyroxine-stimulated Na+ transport were studied in the lower intestinal epithelium (coprodeum) of embryonic chicken in vitro. Isolated tissues of the coprodeum were mounted in Ussing chambers and investigated under voltage-clamped conditions. Simultaneous stimulation with aldosterone (1 mumol.l-1) and thyroxine (1 mumol.l-1) raised short-circuit current after a 1- to 2-h latent period. Maximal values were reached after 6-7 h of hormonal treatment, at which time transepithelial Na+ absorption was more than tripled (77 +/- 11 microA.cm-2) compared to control (24 +/- 8 microA.cm-2). K+ currents across the basolateral membrane were investigated after permeabilizing the apical membrane with the pore-forming antibiotic amphotericin B and application of a mucosal-to-serosal K+ gradient. This K+ current could be dose dependently depressed by the K+ channel blocker quinidine. Fluctuation analysis of the short-circuit current revealed a spontaneous and a blocker-induced Lorentzian noise component in the power density spectra. The Lorentzian corner frequencies increased linearly with the applied blocker concentration. This enabled the calculation of single K+ channel current and K+ channel density. Single K+ channel current was not affected by stimulation, whereas the number of quinidine-sensitive K+ channels in the basolateral membrane increased from 11 to 26.10(6).cm-2 in parallel to the hormonal stimulation transepithelial Na+ transport. This suggests that the basolateral membrane is a physiological target during synergistic aldosterone and thyroxine regulation of transepithelial Na+ transport for maintaining intracellular K+ homeostasis. PMID:8151014

  3. Recalculation of data from 1990 to 2010 on the effects of highly diluted thyroxine on the metamorphosis of highland amphibians

    Directory of Open Access Journals (Sweden)

    Peter Christian Endler

    2011-09-01

    Full Text Available Experiments on amphibian metamorphosis can vary considerably in duration. The authors had set themselves the task of defining a generally applicable pooling method for metamorphosis experiments [1]. Normalization with respect to time was done on the assumption that differences in speed of metamorphosis attributable to treatment would override differences in duration between experiments. The problem of artificial differences in variability when comparing and pooling data from several experiments was approached by normalization with respect to time based on the development of both the test and the control animals. The range from 0% to 100% over which the fraction of four-legged animals progresses in the course of an experiment is divided into 10%-intervals and mapped onto a corresponding relative scale. Each measurement is then assigned to the point on the 10%-scale to which it is closest. In this way each reference point is assigned a value giving the number or percentage of four-legged animals at that point. These values are aggregated over all experiments within the test- and control-group. The results of experiments performed over the course of two decades (1990 - 2010 on highland Rana temporaria treated with a homeopathically prepared high dilution of thyroxine (“30x” are presented in full detail based on this normalization method[1]. It was found that differences between treatment groups thus calculated were in line with those obtained with other pooling methods [2]. Thyroxine 30x does slow down metamorphosis in inert highland amphibians. This was observed by 5 researchers in 20 sub-experiments, and it seems to be the most reliable bio-assay found in amphibian research on homeopathy so far2. When experiments were performed with highland animals pretreated by hyperstimulation with molecular thyroxine, slowing down of metamorphosis was again observed (by 3 of 4 researchers in most of 10 sub-experiments.

  4. D-propranolol and DL-propranolol both decrease conversion of L-thyroxine to L-triiodothyronine.

    OpenAIRE

    Heyma, P; Larkins, R G; Higginbotham, L; Ng, K. W.

    1980-01-01

    The effects of propranolol (DL-propranolol) and D-propranolol on thyroid hormone metabolism were studied in six euthyroid volunteers receiving L-thyroxine (T4) and six hypothyroid patients receiving T4 replacement. D-propranolol as well as propranolol decreased L-triiodothyronine (T3) concentrations and the ratio of T3 to T4 in the euthyroid subjects, and D-propranolol decreased these variables in the subjects with hypothyroidism (propranolol was not given to this group). It is concluded from...

  5. Alterations in 3,3'5'-triiodothyronine metabolism in response to propylthiouracil, dexamethasone, and thyroxine administration in man.

    OpenAIRE

    LoPresti, J S; Eigen, A.; Kaptein, E; Anderson, K P; Spencer, C A; Nicoloff, J. T.

    1989-01-01

    To elucidate the mechanisms involved in altering serum 3,3',5'-triiodothyronine (rT3) levels with absolute or relative low 3,5,3'-triiodothyronine (T3) states in man, agents capable of lowering circulating T3 levels were sequentially administered to six euthyroid subjects. These agents included propylthiouracil (PTU) (300 mg/6 h X 5 d), dexamethasone (DEX) (2 mg/6 h X 5 d), and thyroxine (T4) (3.0 mg load and 0.3 mg/d X 5 d). [125I] rT3 clearance rates and rT3 production rates were then deter...

  6. Role of L-thyroxine in nuclear thyroid hormone receptor occupancy and growth hormone production in cultured GC cells

    OpenAIRE

    Halperin, Y; Shapiro, L E; Surks, M I

    1991-01-01

    The contribution of L-thyroxine (T4) to nuclear thyroid receptor occupancy was studied in GC cells incubated with concentrations of 3,5,3'-triiodo-L-thyronine (T3) and T4 that resulted in free iodothyronine levels similar to those in serum of euthyroid rats. T4 accounted for 5.4-10% of the occupied receptors: T3 derived from T4 [T3(T4)] and T3 added to medium accounted for the remainder of receptor occupancy. Incubation with increasing medium free T4 resulted in a progressive increase in the ...

  7. Influx of Thyroid Hormones into Rat Liver In Vivo: DIFFERENTIAL AVAILABILITY OF THYROXINE AND TRIIODOTHYRONINE BOUND BY PLASMA PROTEINS

    OpenAIRE

    Pardridge, William M.; Mietus, Lawrence J.

    1980-01-01

    The transport of [125I]thyroxine (T4) and [125I]triiodothyronine (T3) into liver was investigated with a tissue sampling-portal vein injection technique in the anesthetized rat. The method allows the investigation of the effects of plasma proteins in human serum on the unidirectional influx of T4 or T3 into liver cells. The percent extraction of unidirectional clearance of T3 and T4 was 77±2% and 43±2%, respectively, after portal injection of a bolus of Ringer's solution. Cell membrane transp...

  8. Effect of Alterations in Thyroid Status on the Metabolism of Thyroxine and Triiodothyronine by Rat Pituitary Gland In Vitro

    OpenAIRE

    Maeda, Michiko; Ingbar, Sidney H.

    1982-01-01

    The metabolism of thyroxine (T4) was studied in slices of rat pituitary gland and liver from the same animal incubated in vitro with [125I]T4 and 10 mM dithiothreitol. In the pituitary gland, generation of 125I-labeled 3,5,3′-triiodothyronine (T3), as well as overall T4 degradation, increased significantly at 24 h after thyroidectomy and by 2 wk were approximately five times control values. Conversely, following a single injection of T3 (1.5 μg/100 g body wt), values for both functions were s...

  9. Simultaneous detection of thyroglobulin (Tg), thyroxine (T4), and Triiodothyronine (T3) in nontoxic thyroid tumors by the immunoperoxidase method.

    OpenAIRE

    Kawaoi, A; Okano, T.; Nemoto, N; Shiina, Y; Shikata, T

    1982-01-01

    In 97 nontoxic thyroid tumors, detection of thyroxine(T4) and triiodothyronine(T3) was attempted by the immunoperoxidase method. T4 was demonstrated in 58 tumors (59.8%) and T3 in 76 (78.4%). The feasibility of biosynthesis of T4 and T3 by such tumors was thus established. In 65 of the tumors, we applied the immunostaining method to serial or semiserial sections to study the correlation among the localizations of thyroglobulin(Tg), T4, and T3. The localization of T4 agreed relatively well wit...

  10. Peripheral tissue mechanism for maintenance of serum triiodothyronine values in a thyroxine-deficient state in man.

    OpenAIRE

    Lum, S M; Nicoloff, J. T.; Spencer, C A; Kaptein, E M

    1984-01-01

    The present study was undertaken to define the source of endogenous triiodothyronine (T3) production responsible for maintaining serum T3 levels in euthyroid subjects with depressed serum thyroxine (T4) values. After withdrawal from 4 wk of exogenous T3 administration, a 22% decline in serum T3 values (from 129 +/- 6 to 99 +/- 4 ng/dl) was observed in six euthyroid subjects, despite a twofold reduction in serum T4 concentrations (from 7.5 +/- 0.5 to 3.2 +/- 0.5 micrograms/dl). This was accomp...

  11. Evidence for Two Tissue-specific Pathways for In Vivo Thyroxine 5′-Deiodination in the Rat

    OpenAIRE

    Silva, J. Enrique; Leonard, Jack L.; Crantz, Frank R.; Larsen, P. Reed

    1982-01-01

    Propylthiouracil (PTU) is a well known inhibitor of thyroxine (T4) to triiodothyronine (T3) conversion as evidenced by its effect in several in vitro systems and by the decrease in serum T3 caused by this drug in either rats or man receiving T4 replacement. However, the failure of PTU to decrease the intrapituitary T3 concentration and to completely blunt the serum T3 concentration in T4-replaced athyreotic rats suggest that there may be a PTU-insensitive pathway of T4 to T3 conversion in som...

  12. Replacement therapy for hypothyroidism with thyroxine alone does not ensure euthyroidism in all tissues, as studied in thyroidectomized rats.

    OpenAIRE

    Escobar-Morreale, Héctor F.; Obregón, María Jesús; Escobar del Rey, Francisco; Morreale de Escobar, Gabriella

    1995-01-01

    We have studied whether, or not, tissue-specific regulatory mechanisms provide normal 3,5,3'-triiodothyronine (T3) concentrations simultaneously in all tissues of a hypothyroid animal receiving thyroxine (T4), an assumption implicit in the replacement therapy of hypothyroid patients with T4 alone. Thyroidectomized rats were infused with placebo or 1 of 10 T4 doses (0.2-8.0 micrograms per 100 grams of body weight per day). Placebo-infused intact rats served as controls. Plasma and 10 tissues w...

  13. Iodothyronine Release from the Perfused Canine Thyroid following Cessation of Stimulation: RAPID DECLINE OF TRIIODOTHYRONINES IN COMPARISON WITH THYROXINE

    OpenAIRE

    Laurberg, Peter

    1980-01-01

    The kinetics of thyroid secretion after termination of stimulation by 100 μU/ml bovine thyroid stimulating hormone (TSH) or 5 mM cyclic AMP (cAMP) were studied using perfused canine thyroid lobes. All experiments were performed as paired comparisons, one thyroid lobe acting as a control continuing to receive infusion of the stimulator. 2.5 h after termination of TSH infusion, the secretion of thyroxine (T4), 3,5,3′-triiodothyronine (T3), and 3,3′,5′-triiodothyronine (rT3) was not significantl...

  14. Effect of suppressive L-thyroxine therapy on lipid profile of children and adolescents with thyroid carcinoma

    International Nuclear Information System (INIS)

    The study of lipid profile indexes was performed among children and adolescents (n=403) being operated on thyroid carcinoma and, consequently, undertaken suppressive doses of L-thyroxin (3.0 μkg/kg body weight/daily). There was a significant increase in average levels of total lipids (TL), total cholesterol (TC), LDL-cholesterol, triglycerides and atherogenity coefficient (K= [TC-HDL-C] / HDL-C) and the average level of HDL-C decrease as compared to the control group. Under the TSH suppression there was positive dynamics in TC and LDL-C levels as compared to patients with postoperative hypothyroidism

  15. Auroral Phenomena in Brown Dwarf Atmospheres

    Science.gov (United States)

    Pineda, J. Sebastian; Hallinan, Gregg

    2016-01-01

    Since the unexpected discovery of radio emission from brown dwarfs some 15 years ago, investigations into the nature of this emission have revealed that, despite their cool and neutral atmospheres, brown dwarfs harbor strong kG magnetic fields, but unlike the warmer stellar objects, they generate highly circularly polarized auroral radio emission, like the giant planets of the Solar System. Our recent results from Keck LRIS monitoring of the brown dwarf LSR1835+32 definitively confirm this picture by connecting the auroral radio emission to spectroscopic variability at optical wavelengths as coherent manifestations of strong large-scale magnetospheric auroral current systems. I present some of the results of my dissertation work to understand the nature brown dwarf auroral phenomena. My efforts include a survey of Late L dwarfs and T dwarfs, looking for auroral Hα emission and a concurrent survey looking for the auroral emission of H3+ from brown dwarfs with radio pulse detections. I discuss the potential connection of this auroral activity to brown dwarf weather phenomena and how brown dwarf aurorae may differ from the analogous emission of the magnetized giant planets in the Solar System.

  16. Brown Dwarfs at the Exoplanet Mass Boundary

    Science.gov (United States)

    Faherty, J. K.; Cruz, K. L.; Rice, E. L.; Riedel, A.

    2014-10-01

    Young brown dwarfs and directly-imaged exoplanets have enticingly similar photometric and spectroscopic characteristics, indicating that their cool, low gravity atmospheres should be studied in concert. Similarities between the peculiar shaped H band, near and mid-IR photometry as well as location on color magnitude diagrams provide important clues about how to extract physical properties of planets from current brown dwarf observations. Our team has assigned >30 brown dwarfs to 10-150 Myr nearby moving groups. In so doing, we have discovered important diversity among this extremely low-mass (10 - 30 M_{Jup}) age-calibrated sample indicating that cloud properties play a critical role in their observables.

  17. Study on Extrusion Technological Parametersof Brown Rice

    Institute of Scientific and Technical Information of China (English)

    ZhuYongyi; ZhouXianqing; LingLizhong

    2001-01-01

    Abstract: Extrusion is an efficient measure to improve the texture and physic-chemical properties of brown rice. The polynomial degree two model of extrusiontechnological parameters and gelatinized degree, water absorption index, water solubleindex and moisture content of extruded matter was obtained by methods of single factorand response surface methodology, R2=0.9649, 0.8745, 0.9079, 0.8677. The optimaltechnoiogica! parameters of brown rice extrusion were figured out as follows:moisturecontent of brown rice, 11.42%, speed of screw, 30rpm, feeding speed, and 20rpm.

  18. Young Brown Dwarfs as Giant Exoplanet Analogs

    CERN Document Server

    Faherty, Jacqueline K; Rice, Emily L; Riedel, Adric

    2013-01-01

    Young brown dwarfs and directly-imaged exoplanets have enticingly similar photometric and spectroscopic characteristics, indicating that their cool, low gravity atmospheres should be studied in concert. Similarities between the peculiar shaped H band, near and mid-IR photometry as well as location on color magnitude diagrams provide important clues about how to extract physical properties of planets from current brown dwarf observations. In this proceeding we discuss systems newly assigned to 10-150 Myr nearby moving groups, highlight the diversity of this uniform age-calibrated brown dwarf sample, and reflect on their implication for understanding current and future planetary data.

  19. Radioimmunoassay of ''free thyroxin'' in dried blood spots on filter paper - preliminary observations on the effective differentiation of subjects with congenital hypothyroidism from those with subnormal thyroxin-binding globulin and normal subjects

    International Nuclear Information System (INIS)

    In this sensitive, simple method for measuring ''free thyroxin'' (FT4) in eluates of dried blood spots on filter paper by use of a radioimmunoassay kit (Amerlex Free T4 RIA), the measurable range of FT4 is 1.8 to 57 ng/L (equivalent to the concentration in serum), or 7 to 237 fg/tube. The mean coefficients of variation for within assay-within spots, within assay-between spots, and between assays were 5.3%, 5.0%, and 6.2%, respectively. FT4 in blood spotted on filter paper is stable for at least a month when dried and kept at either -200C, 40C, room temperature (about 250C), or 370C. The results for FT4 in dried blood spots correlated closely with the free-T4 concentration in serum (r = 0.99). The method can be used to differentiate cases of primary and secondary hypothyroidism from normal subjects and those with subnormal thyroxin-binding globulin. This method may be useful in screening for congenital hypothyroidism, because sample-retesting is not necessary

  20. Radioimmunoassay of ''free thyroxin'' in dried blood spots on filter paper - preliminary observations on the effective differentiation of subjects with congenital hypothyroidism from those with subnormal thyroxin-binding globulin and normal subjects

    Energy Technology Data Exchange (ETDEWEB)

    Mizuta, H.; Miyai, K.; Ichihara, K.; Amino, N.; Harada, T.; Nose, O.; Tanizawa, O.

    1982-03-01

    In this sensitive, simple method for measuring ''free thyroxin'' (FT/sub 4/) in eluates of dried blood spots on filter paper by use of a radioimmunoassay kit (Amerlex Free T/sub 4/ RIA), the measurable range of FT/sub 4/ is 1.8 to 57 ng/L (equivalent to the concentration in serum), or 7 to 237 fg/tube. The mean coefficients of variation for within assay-within spots, within assay-between spots, and between assays were 5.3%, 5.0%, and 6.2%, respectively. FT/sub 4/ in blood spotted on filter paper is stable for at least a month when dried and kept at either -20/sup 0/C, 4/sup 0/C, room temperature (about 25/sup 0/C), or 37/sup 0/C. The results for FT/sub 4/ in dried blood spots correlated closely with the free-T/sub 4/ concentration in serum (r = 0.99). The method can be used to differentiate cases of primary and secondary hypothyroidism from normal subjects and those with subnormal thyroxin-binding globulin. This method may be useful in screening for congenital hypothyroidism, because sample-retesting is not necessary.

  1. A Ketogenic Diet Increases Brown Adipose Tissue Mitochondrial Proteins and UCP1 Levels in Mice

    OpenAIRE

    Srivastava, Shireesh; Baxa, Ulrich; Niu, Gang; Chen, Xiaoyuan; Veech, Richard L.

    2012-01-01

    We evaluated the effects of feeding a ketogenic diet (KD) for a month on general physiology with emphasis on brown adipose tissue (BAT) in mice. KD did not reduce the caloric intake, or weight or lipid content of BAT. Relative epididymal fat pads were 40% greater in the mice fed the KD (P = 0.06) while leptin was lower (P < 0.05). Blood glucose levels were 30% lower while D-β-hydroxybutyrate levels were about 3.5-fold higher in the KD group. Plasma insulin and leptin levels in the KD group we...

  2. Regulation of gene expression by FSP27 in white and brown adipose tissue

    OpenAIRE

    Xue Bofu; Wang Yue; Zhou Linkang; Xu Li; Zhang Yinxin; Li(李, Li, 莉); Wen Zilong; Li Peng; Sang Jianli

    2010-01-01

    Abstract Background Brown and white adipose tissues (BAT and WAT) play critical roles in controlling energy homeostasis and in the development of obesity and diabetes. The mouse Fat-Specific protein 27 (FSP27), a member of the cell death-inducing DFF45-like effector (CIDE) family, is expressed in both BAT and WAT and is associated with lipid droplets. Over-expression of FSP27 promotes lipid storage, whereas FSP27 deficient mice have improved insulin sensitivity and are resistant to diet-induc...

  3. Impact of Age on the Relationships of Brown Adipose Tissue With Sex and Adiposity in Humans

    OpenAIRE

    Pfannenberg, Christina; Werner, Matthias K.; Ripkens, Sabine; Stef, Irina; Deckert, Annette; Schmadl, Maria; Reimold, Matthias; Häring, Hans-Ulrich; Claussen, Claus D.; Stefan, Norbert

    2010-01-01

    OBJECTIVE Brown adipose tissue (BAT) regulates energy homeostasis and fat mass in mammals and newborns and, most likely, in adult humans. Because BAT activity and BAT mass decline with age in humans, the impact of BAT on adiposity may decrease with aging. In the present study we addressed this hypothesis and further investigated the effect of age on the sex differences in BAT activity and BAT mass. RESEARCH DESIGN AND METHODS Data from 260 subjects (98 with BAT and 162 study date–matched cont...

  4. Fat tissue, aging, and cellular senescence.

    OpenAIRE

    Tchkonia, T.; Morbeck, D.E.; Zglinicki, T. von; Deursen, J.M.A. van; Lustgarten, J.; Scrable, H.; Khosla, S.; Jensen, M.D.; Kirkland, J L

    2010-01-01

    Fat tissue, frequently the largest organ in humans, is at the nexus of mechanisms involved in longevity and age-related metabolic dysfunction. Fat distribution and function change dramatically throughout life. Obesity is associated with accelerated onset of diseases common in old age, while fat ablation and certain mutations affecting fat increase life span. Fat cells turn over throughout the life span. Fat cell progenitors, preadipocytes, are abundant, closely related to macrophages, and dys...

  5. Processing and phosphorylation of the Fat receptor

    OpenAIRE

    Feng, Yongqiang; Irvine, Kenneth D.

    2009-01-01

    The Drosophila tumor suppressors fat and discs overgrown (dco) function within an intercellular signaling pathway that controls growth and polarity. fat encodes a transmembrane receptor, but post-translational regulation of Fat has not been described. We show here that Fat is subject to a constitutive proteolytic processing, such that most or all cell surface Fat comprises a heterodimer of stably associated N- and C-terminal fragments. The cytoplasmic domain of Fat is phosphorylated, and this...

  6. Signal transduction by the Fat cytoplasmic domain

    OpenAIRE

    Pan, Guohui; Feng, Yongqiang; Ambegaonkar, Abhijit A.; Sun, Gongping; Huff, Matthew; Rauskolb, Cordelia; Irvine, Kenneth D.

    2013-01-01

    The large atypical cadherin Fat is a receptor for both Hippo and planar cell polarity (PCP) pathways. Here we investigate the molecular basis for signal transduction downstream of Fat by creating targeted alterations within a genomic construct that contains the entire fat locus, and by monitoring and manipulating the membrane localization of the Fat pathway component Dachs. We establish that the human Fat homolog FAT4 lacks the ability to transduce Hippo signaling in Drosophila, but can trans...

  7. Effects of thyroxine and 1-methyl, 2-mercaptoimidazol on phosphoinositides synthesis in rat liver

    Directory of Open Access Journals (Sweden)

    Krasilnikova Oksana A

    2004-12-01

    Full Text Available Abstract Background Phosphoinositides mediate one of the intracellular signal transduction pathways and produce a class of second messengers that are involved in the action of hormones and neurotransmitters on target cells. Thyroid hormones are well known regulators of lipid metabolism and modulators of signal transduction in cells. However, little is known about phosphoinositides cycle regulation by thyroid hormones. The present paper deals with phosphoinositides synthesis de novo and acylation in liver at different thyroid status of rats. Results The experiments were performed in either the rat liver or hepatocytes of 90- and 720-day-old rats. Myo-[3H]inositol, [14C]CH3COONa, [14C]oleic and [3H]arachidonic acids were used to investigate the phosphatidylinositol (PtdIns, phosphatidylinositol 4-phosphate and phosphatidylinositol 4,5-bisphosphate (PtdInsP2 synthesis. 1-methyl, 2-mercaptoimidazol-induced hypothyroidism was associated with the decrease of myo-[3H]inositol and [3H]arachidonic acids incorporation into liver phosphoinositides and total phospholipids, respectively. The thyroxine (L-T4 injection to hypothyroid animals increased the hormones contents in blood serum and PtdInsP2 synthesis de novo as well as [3H]arachidonic acids incorporation into the PtdIns and PtdInsP2. Under the hormone action, the [14C]oleic acid incorporation into PtdIns reduced in the liver of hypothyroid animals. A single injection of L-T4 to the euthyroid [14C]CH3COONa-pre-treated animals or addition of the hormone to a culture medium of hepatocytes was accompanied by the rapid prominent increase in the levels of the newly synthesized PtdIns and PtdInsP2 and in the mass of phosphatidic acid in the liver or the cells. Conclusions The data obtained have demonstrated that thyroid hormones are of vital importance in the regulation of arachidonate-containing phosphoinositides metabolism in the liver. The drug-induced malfunction of thyroid gland noticeably changed the

  8. Improvement in subclinical cognitive dysfunction with thyroxine therapy in hypothyroidism: A study from tertiary care center

    Directory of Open Access Journals (Sweden)

    Sridevi Paladugu

    2015-01-01

    Full Text Available Aim: To evaluate the effect of hypothyroidism (both overt and subclinical on cognitive function using latencies of P300 auditory evoked potentials (AEPs. P300 latency suggests that shorter latency times are related to better cognitive performance. P300 latencies were also done after thyroxine replacement to see the effect of treatment on cognitive function. Materials and Methods: Biochemically proven new onset cases with hypothyroidism (overt and subclinical were enrolled into the study, AEPs of these two groups when compared with matched controls. After detailed history and physical examination, P300 potentials were recorded at two points Cz and Pz (Cz: On the midline of the head at the vertex, Pz: On the midline of the head between the vertex and occipital protuberance using a Nicolet Viking Select neuro diagnostic system version 10.0. The study was done in electrophysiology lab in Osmania Medical College. Results: A patient characteristics of both cases and controls were comparable. The cases consisted of two groups, overt hypothyroid cases 24, mean thyroid stimulating hormone (TSH values in them was 94, subclinical cases 21 in whom mean TSH value was 12.3. Mean P300 latencies of all cases at Cz was 342.42 ± 29.5 ms, and at Pz was 345.4 ± 30 ms. Mean P300 latencies of controls at Cz was 296.4 ± 34 ms and at Pz was 297.9 ± 33 ms (difference in P < 0.001. Mean P300 values in overt cases were 362.6 ± 32.9 ms at Cz, and at Pz it was 362.5 ± 33.9 ms. Mean P300 values in subclinical cases were 319.3 ± 30.9 ms at Cz, and at Pz it was 316.4 ± 27.9 ms. P300 values in overt cases were highly significant as compared to controls, and P300 values in the subclinical cases versus controls were also significant (P < 0.001. Conclusion: P300 latency prolongation in both clinical and subclinical hypothyroid cases shows that cognitive function is affected adversely in hypothyroidism including the subclinical hypothyroid cases. Larger studies evaluating

  9. [Advantages, disadvantages and selection methods of thyroxine measurement--comparison of CPBA and RIA].

    Science.gov (United States)

    Bunko, H; Hisada, K

    1976-10-01

    Although recent progress in radioimmunoassay (RIA) permitted direct RIA for thyroxine (T4), there appeared few reports evaluating clinical applicability of T4 RIA as routine method. The authors evaluated advantage, disadvantage of methods for T4 measurement in comparison between CPBA (competitive protein binding analysis) and RIA, and tried to discuss about selection of methods for T4 measurement. Res-O-Mat T4 was chosen as CPBA, and RIAMAT-T4(St) and T4-RIAKIT(Sp) were chosen as RIAs. Detailed descriptions about both RIA methods appeared elsewhere [2, 3]. From the basic experiments, reproducibility of CPBA, St and Sp within assay were 5.8% (C.V.), 4.0% (C.V.), and 8.5%(C.V.) respectively, and mean recovery rates were 92.2%, 100.7% and 96.1% respectively. T4 value measured by both RIAs correlated well with CPBA, and St showed slightly lower value and Sp showed slightly higher value than CPBA. The normal ranges for RIAs were 3.7-11.7 microng% (St) and 4.6-15.2 microng% (Sp). Diagnostic accuracy for hyperthyroid state were 83.3% (CPBA), 85.7%(St) and 69.2% (Sp), and for euthyroid state were 92.0% (CPBA), 98.8% (St) and 95.7% (Sp). The diagnostic accuracy for hypothyroid state in three methods were lowest. From the economical point of view, cost performance, time performance and total time for single assay were analysed and mathematical equations were obtained from actual assay by each methods. When the number of samples per single assay was less than 10, CPBA was most economic in terms of cost and time performance and total time required. In the assay of more than 20 samples, RIAs were efficient in each point of views. In the point of view of sample volumes required, RIAs were most promising. The authors concluded that guides for selection of methods in T4 assay were as follows: A) CPBA was most efficient in local use especially when less than 10 samples were frequently to be assayed. B) RIAs were efficient in batch processing more than 20 samples, especially in

  10. Magnetic resonance imaging of autologous fat grafting

    International Nuclear Information System (INIS)

    A 30-year-old female patient with isolated facial lipodystrophy underwent two sessions of fat injection. MR signals of injected fat at different injection ages were compared to native fat. Native T1 signal was smaller for transplant fat, probably due to a slightly lower fat content and/or fibrosis or due to higher perfusion. T2 signal of transplants was significantly higher than that of native fat. T1 post-contrast was also higher, and contrast uptake of transplanted fat increased slightly with transplant age, which could be explained by an increasing perfusion. This study demonstrates the differences and MR signal time changes of native and transplanted fat. (orig.)

  11. European brown hare syndrome virus in free-ranging European brown hares from Argentina

    DEFF Research Database (Denmark)

    Frolich, K.; Kujawski, G.E.J.G.; Rudolph, M.;

    2003-01-01

    From 1998 to 2000, serum samples of 80 shot European brown hares (Lepus europaeus) from Argentina were examined for antibodies against European brown hare syndrome virus (EBHSV) and 80 spleen samples were tested for EBHSV-antigen by enzyme linked immunosorbent assay (ELISA). Nine hares were posit...... in these hares. This is the first report of antibodies to EBHSV, EBHSV-antigen, and electron microscopy findings in free-ranging European brown hares from South America....

  12. Mesotherapy for local fat reduction.

    Science.gov (United States)

    Jayasinghe, S; Guillot, T; Bissoon, L; Greenway, F

    2013-10-01

    Mesotherapy, which is the injection of substances locally into mesodermally derived subcutaneous tissue, developed from empirical observations of a French physician in the 1950s. Although popular in Europe for many medical purposes, it is used for local cosmetic fat reduction in the United States. This paper reviews manuscripts indexed in PubMed/MEDLINE under 'mesotherapy', which pertains to local fat reduction. The history of lipolytic mesotherapy, the physiology of body fat distribution, the mechanism of action of different lipolytic stimulators and their increased efficacy in combination are reviewed. Mesotherapy falls into two categories. Lipolytic mesotherapy using lipolytic stimulators requires more frequent treatments as the fat cells are not destroyed and can refill over time. Ablative mesotherapy destroys fat cells with a detergent, causes inflammation and scarring from the fat necrosis, but requires fewer treatments. The historic and empiric mixing of sodium channel blocking local anaesthetics in mesotherapy solutions inhibits the intended lipolysis. Major mesotherapy safety concerns include injection site infections from poor sterile technique. Cosmetic mesotherapy directs the area from which fat is lost to improve self-image. Studies were of relatively small number, many with limited sample sizes. Future research should be directed towards achieving a Food and Drug Administration indication rather than continuing expansion of off-label use. PMID:23800269

  13. Browns Park NWR Water Use Report- 1997

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This report contains locations and water use at Browns Park NWR for 1997. A general background is presented first with water rights information, management...

  14. Browns Park NWR Water Use Report- 1993

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This report contains locations and water use at Browns Park NWR for 1993. A general background is presented first with water rights information, management...

  15. Browns Park NWR Water Use Report- 1988

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This report contains locations and water use at Browns Park NWR for 1988. A general background is presented first with water rights information, management...

  16. Browns Park NWR Water Use Report- 1989

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This report contains locations and water use at Browns Park NWR for 1989. A general background is presented first with water rights information, management...

  17. Browns Park NWR Water Use Report- 1991

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This report contains locations and water use at Browns Park NWR for 1991. A general background is presented first with water rights information, management...

  18. Browns Park NWR Water Use Report- 1995

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This report contains locations and water use at Browns Park NWR for 1995. A general background is presented first with water rights information, management...

  19. Browns Park NWR Water Use Report- 1992

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This report contains locations and water use at Browns Park NWR for 1992. A general background is presented first with water rights information, management...

  20. Browns Park NWR Water Use Report- 1998

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This report contains locations and water use at Browns Park NWR for 1998. A general background is presented first with water rights information, management...

  1. Browns Park NWR Water Use Report- 1996

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This report contains locations and water use at Browns Park NWR for 1996. A general background is presented first with water rights information, management...

  2. Browns Park NWR Water Use Report- 1994

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This report contains locations and water use at Browns Park NWR for 1994. A general background is presented first with water rights information, management...

  3. Browns Park NWR Water Use Report- 1990

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This report contains locations and water use at Browns Park NWR for 1990. A general background is presented first with water rights information, management...

  4. Telemetry techniques used on Kodiak brown bear

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This report summarizes the results of a study on the techniques used to monitor the movements of Kodiak brown bears instrumented with radio transmitters. Methods...

  5. Mediastinal Parathyroid Adenoma and Brown Tumors

    OpenAIRE

    Bernal, P.; Ucros, G.; Mejia, A

    2012-01-01

    In this report, we describe a rare case of brown tumor and mediastinal parathyroid adenoma. This report emphasizes the value of radionuclide scintigraphy in the setting of persistent disease following parathyroid surgery.

  6. Ezra Brown named Alumni Distinguished Professor

    OpenAIRE

    Cox, Clara B.

    2005-01-01

    The Virginia Tech Board of Visitors conferred the title Alumni Distinguished Professor (ADP) to Ezra "Bud" Brown, professor of mathematics in the College of Science, in recognition of his extraordinary academic citizenship and distinguished service within the Virginia Tech community.

  7. Browns Park NWR Water Use Report- 2012

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This report contains locations and water use at Browns Park NWR for 2012. After the creation of the Flaming Gorge Dam, the annual flooding of the Green River ceased...

  8. Browns Park NWR Water Use Report- 2007

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This report contains locations and water use at Browns Park NWR for 2007. After the creation of the Flaming Gorge Dam, the annual flooding of the Green River ceased...

  9. Browns Park NWR Water Use Report- 2011

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This report contains locations and water use at Browns Park NWR for 2011. After the creation of the Flaming Gorge Dam, the annual flooding of the Green River ceased...

  10. Browns Park NWR Water Use Report- 2010

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This report contains locations and water use at Browns Park NWR for 2010. After the creation of the Flaming Gorge Dam, the annual flooding of the Green River ceased...

  11. Browns Park NWR Water Use Report- 2008

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This report contains locations and water use at Browns Park NWR for 2008. After the creation of the Flaming Gorge Dam, the annual flooding of the Green River ceased...

  12. Browns Park NWR Water Use Report- 2006

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This report contains locations and water use at Browns Park NWR for 2006. After the creation of the Flaming Gorge Dam, the annual flooding of the Green River ceased...

  13. Browns Park NWR Water Use Report- 2005

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This report contains locations and water use at Browns Park NWR for 2005. After the creation of the Flaming Gorge Dam, the annual flooding of the Green River ceased...

  14. Browns Park NWR Water Use Report- 2009

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This report contains locations and water use at Browns Park NWR for 2009. After the creation of the Flaming Gorge Dam, the annual flooding of the Green River ceased...

  15. Browns Park NWR Water Use Report- 2013

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This report contains locations and water use at Browns Park NWR for 2013. After the creation of the Flaming Gorge Dam, the annual flooding of the Green River ceased...

  16. Brown CA et al 2016 Dataset

    Data.gov (United States)

    U.S. Environmental Protection Agency — This dataset contains the research described in the following publication: Brown, C.A., D. Sharp, and T. Mochon Collura. 2016. Effect of Climate Change on Water...

  17. Brown bear telemetry and trapping: Special report

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — Brown bear studies were continued during the 1967 field season with emphasis on development of techniques for instrumenting bears with radio transmitters and...

  18. Development of a two step radioimmunoassay procedure based on coated tubes for the measurement of free-thyroxine in serum

    International Nuclear Information System (INIS)

    We describe a two-step radioimmunoassay procedure for the measurement of free thyroxine (fT4) in serum using high affinity antibody immobilized on the inner walls of the polystyrene tubes. The thyroid hormones are circulating in the bound and free form and they exist in dynamic equilibrium. The fT4 concentration in normal subjects ranges from 7 to 21 pg/ml which is only 0.02% of the total thyroxine present. Hence, high affinity antibody was used to achieve the required sensitivity and the use of extremely small amount of antibody ensured that the bound free equilibrium is not disturbed. In the optimized assay system T4 sequestration by the antibody from the normal serum sample was kept below 1%. The detection limit of the assay developed is less than 2 pg/ml. The intra and inter assay variability of the assay at low and high clinical limits were less than 10% and 15% respectively. The system developed was compared with the commercial kit using 45 volunteers samples. The fT4 concentrations measured using our system was comparable with that obtained using the commercial kit. The correlation coefficient was found to be 0.85. (author)

  19. Thyroxine (T4) radioimmunoassay using filter paper dried blood sample: an attempt for screening of neonates for hypothyroidism

    International Nuclear Information System (INIS)

    This paper describes a sensitive but simple and less expensive method suitable for estimation of thyroxine (T4) level. Deficiency of iodine during fetal life results in neonatal hypothyroidism and critinism. Frequency of neonatal hypothyroidism is 1 in 5000 to 7000 in countries having iodine deficiency. It is therefore important to diagnose the neonatal hypothyroidism as soon as possible after birth. The estimation of thyroxine has been found to the a reliable index for diagnosis of hypothyroidism and has long been used for screening of neonatal hypothyroidism. In the present study, instead of serum sample, a 6 mm disc of filter paper containing dried blood sample was used. The test was carried out in the laboratory with 40 samples. As compared to the sensitivity of serum sample technique which is 15.19 n mol/L, the filter paper technique has the sensitivity of 17.23 n mol/L. The work revealed that the T4 concentration do not depend upon the amount of blood on the filter paper. Effect of temperature on filter paper disc was evaluated at 4o c, at 25o c and at 37o c. Results obtained showed significant variation and the best result was obtained for the sample kept at 4o c. The method is simple, rapid, less expensive and needs a small amount of blood and is, therefore, a useful technique for mass screening of neonatal hypothyroidism. 6 refs., 4 tables (author)

  20. The effect of long term thyroxine replacement on Bone Mineral Density in patients with Well-Differentiated Thyroid Carcinoma (DTC)

    International Nuclear Information System (INIS)

    Full text: Objective: To date a few studies have focused on the effects of subclinical hyperthyroidism on bone metabolism and have shown conflicting results. This study was undertaken to evaluate this possibility. Material and Methods: Sixty-six patients (22 premenopausal women, 33 postmenopausal women, 11 men) who had received iodine-131 ablation postoperatively due to differentiated thyroid cancer (DTC) entered the study and were compared with the healthy controls individually matched to patients for age, gender and menopausal status. The bone mineral density (BMD) of lumbar and femoral regions of the patients and healthy group were compared using T test. Results: There was no significant difference in BMD between patients and control in any subgroup for the lumbar spine (P value >0.05). Analysis of data from the femoral BMD of the men, premenopausal patients and controls again showed no difference in bone density while only the mean of femoral BMD in postmenopausal females in cases was significantly lower than control group (p value =0.05).Conclusion: Our findings suggest that replacement doses of thyroxine do not have a significant effect on BMD in men and also premenopausal females and hence on risk of osteoporosis. However, reduction only in femoral BMD during treatment with long term levothyroxine among postmenopausal females was observed. It is necessary to be aware of the additional risk of bone loss associated with thyroxine therapy in postmenopausal women. Careful monitoring of thyroid status in these groups of patients is necessary to avoid over treatment. (author)

  1. Cellular mechanisms of reduced sarcoplasmic reticulum Ca2+ content in L-thyroxin-induced rat ventricular hypertrophy

    Institute of Scientific and Technical Information of China (English)

    Lai-jing SONG; Guan-lei WANG; Jie LIU; Qin-ying QIU; Jing-hua OU; Yong-yuan GUAN

    2008-01-01

    Aim:To examine how the sarcoplasmic reticulum (SR) Ca2+ content changes and the underlying mechanism in L-thyroxin-induced cardiac hypertrophy. Methods:Echocardiography was used to confirm the establishment of the cardiac hypertro-phy model. The confocal microscopy and fluorescent indicator Fluo-3 was ap-plied to examine the intracellular Ca2+ concentration ([Ca2+]I), the Ca2+ sparks, and the caffeine-induced Ca2+ transient in freshly isolated cardiac ventricular myocytes. The activity of sarcolemmal and SR Ca2+-ATPase 2a (SERCA2a) in the ventricular tissue was also measured, respectively. Results:L-thyroxin (1 mg/kg injection for 10 d) induces left ventricular cardiac hypertrophy with normal myocardial function. The decreased caffeine-induced Ca2+ transient in the Ca2+-free solution was detected. The spontaneous Ca2+ sparks in hypertrophied myocytes occurred more frequently than in normal cells, with similar duration and spatial spread, but smaller amplitude. Then the basal [Ca2+]I increase was observed in quiescent left ventricular myocytes from hyperthyroidism rats. The activity of sarcolemmal and SR Ca2+-ATPase was decreased in the hypertrophied ventricle tissue. Conclusion:The results suggested that the reduced SR Ca2+ content may be associated with an increased Ca2+ leak and reduced SERCA2a activity, contributing to abnormal intracellular Ca2+ handling during hypertrophy in hyperthyroidism rats.

  2. Candle power at Browns Ferry

    International Nuclear Information System (INIS)

    An account is given of the serious accident that occurred to the Browns Ferry nuclear power station in Alabama on March 22 1975, when a fire caused by an electrician searching for air leaks using a candle caused great damage to the reactor. The fire put several key safety systems out of action and caused problems in shutting down one of the plant's two reactors. The use of a candle for the purpose was regarded as a highly unofficial but time-honoured method. In this case the candle ignited polyurethane foam surrounding some electrical cables, and the fire spread back through the reactor walls. Some alarming features of the fire fighting effort are noted. The use of water finally quickly extinguished the fire. The unconventional means that had to be adopted to shut down the reactors are described. Implications of the accident for other plants are being considered and modifications are suggested. There were no adverse effects on public health and safety. (author)

  3. Glycerol-3-phosphate Acyltransferase Isoform-4 (GPAT4) Limits Oxidation of Exogenous Fatty Acids in Brown Adipocytes.

    Science.gov (United States)

    Cooper, Daniel E; Grevengoed, Trisha J; Klett, Eric L; Coleman, Rosalind A

    2015-06-12

    Glycerol-3-phosphate acyltransferase-4 (GPAT4) null pups grew poorly during the suckling period and, as adults, were protected from high fat diet-induced obesity. To determine why Gpat4(-/-) mice failed to gain weight during these two periods of high fat feeding, we examined energy metabolism. Compared with controls, the metabolic rate of Gpat4(-/-) mice fed a 45% fat diet was 12% higher. Core body temperature was 1 ºC higher after high fat feeding. Food intake, fat absorption, and activity were similar in both genotypes. Impaired weight gain in Gpat4(-/-) mice did not result from increased heat loss, because both cold tolerance and response to a β3-adrenergic agonist were similar in both genotypes. Because GPAT4 comprises 65% of the total GPAT activity in brown adipose tissue (BAT), we characterized BAT function. A 45% fat diet increased the Gpat4(-/-) BAT expression of peroxisome proliferator-activated receptor α (PPAR) target genes, Cpt1α, Pgc1α, and Ucp1, and BAT mitochondria oxidized oleate and pyruvate at higher rates than controls, suggesting that fatty acid signaling and flux through the TCA cycle were enhanced. To assess the role of GPAT4 directly, neonatal BAT preadipocytes were differentiated to adipocytes. Compared with controls, Gpat4(-/-) brown adipocytes incorporated 33% less fatty acid into triacylglycerol and 46% more into the pathway of β-oxidation. The increased oxidation rate was due solely to an increase in the oxidation of exogenous fatty acids. These data suggest that in the absence of cold exposure, GPAT4 limits excessive fatty acid oxidation and the detrimental induction of a hypermetabolic state. PMID:25918168

  4. Dining centers cut trans fats

    OpenAIRE

    Gehrt, Katie

    2007-01-01

    Dining Services has pulled ahead of the pack in cutting trans fat from its menus--surpassing restaurants like Burger King, KFC, Taco Bell, and others who have announced that they also will be making the change this spring.

  5. MRI of Hoffa's fat pad

    International Nuclear Information System (INIS)

    The infrapatellar fat pad of Hoffa is commonly injured but rarely discussed in the radiological literature. Abnormalities within it most commonly are the consequences of trauma and degeneration, but inflammatory and neoplastic diseases of the synovium can be confined to the fat pad. The commonest traumatic lesions follow arthroscopy, but intrinsic signal abnormalities can also be due to posterior and superior impingements syndromes and following patellar dislocation. Infrapatellar plica syndrome may also be traumatic in aetiology. The precise aetiology of ganglion cysts is not understood; the principal differential diagnosis is a meniscal or cruciate cyst. Hoffa's fat pad contains residual synovial tissue, meaning that primary neoplastic conditions of synovium may originate and be confined to the fat pad. Inflammatory changes along the posterior border of the pad may also be used to help differentiate effusion from acute synovitis on unenhanced MR examinations. (orig.)

  6. Corticosteroids for fat embolism after multiple fractures

    Institute of Scientific and Technical Information of China (English)

    CHEN Huai-sheng; ZHANG Qing-mei; WEN Jun-min; WEN Shun-kang; YI Jing; ZHOU Zhi-qiang; WU Sheng-nan

    2007-01-01

    @@ Fat embolism is a common complication of multiple fractures. Corticosteroids are usually prescribed in prophylactic and treatment of fat embolism. A case of fat embolism followed multiple fractures was hospitalized, and we searched best evidences about corticosteroids for fat embolism so as to provide best therapeutics for the patient.

  7. European brown hare syndrome virus in free-ranging European brown hares from Argentina

    DEFF Research Database (Denmark)

    Frolich, K.; Kujawski, G.E.J.G.; Rudolph, M.; Rønsholt, L.; Speck, S.

    2003-01-01

    From 1998 to 2000, serum samples of 80 shot European brown hares (Lepus europaeus) from Argentina were examined for antibodies against European brown hare syndrome virus (EBHSV) and 80 spleen samples were tested for EBHSV-antigen by enzyme linked immunosorbent assay (ELISA). Nine hares were...

  8. THYROID STIMULATING HORMONE AND THYROXINE SCREENING IN THE PRETERM NEWBORN: REFERENCE VALUES

    Directory of Open Access Journals (Sweden)

    Franco Bagnoli

    2013-12-01

    Full Text Available The screening test for Congenital Hypothyroidism, performed in the 2nd - 3rd day of life, highlighted in the premature infant significant lower levels of thyroid stimulating hormone (TSH and thyroxine (tT4 than those found in the full term newborn. Studies carried out after birth in the preterm infant, showed a persistence of low levels of thyroid hormones (TH in the first two weeks of life, with a tendency toward spontaneous resolution at the end of the first month. This hormone deficiency has an incidence which is inversely related to gestational age (GA. However, there are no works which have evaluated the levels of TSH and tT4 in an appropriate large population of extremely low gestational age newborns (ELGANs in the 2nd - 3rd day of life divided by different GAs. To assess the levels of TSH and tT4 in the 2nd - 3rd day of life, from the lowest GA up to the end, in order to indicate the reference values which can be used to establish whether a replacement therapy with thyroid hormones in the premature infant is useful or not. In the present study we examined a total population of 1,671 adapted for gestational age newborns (AGA of which 1,159 resulted in full term and 512 resulted in preterm. The population was divided into eight groups of GAs (23-25, 26-28, 29-30, 31-32, 33-34, 35-36, 37-38, 39-42 wks and for each age group the median values of TSH and tT4 was determined. The TSH and tT4 were obtained in the 2nd - 3rd day of life at the screening for Congenital Hypothyroidism. Looking at the whole population examined, the preterm infant presents sig- nificant lower levels of TSH (p=0,00036 and tT4 (p<0,00001 compared to the full term newborn in the 2nd - 3rd day of life. TSH and tT4 levels increase gradually with the advancing of GA, reflecting the progressive maturation of the hypothalamic-pituitary-thyroid axis. A linear and significant correlation (p=0,001 was found between the levels of tT4 and GA. Instead, the TSH values which show an

  9. Oral Liquid l-Thyroxine (l-T4) May Be Better Absorbed Compared to l-T4 Tablets Following Bariatric Surgery

    OpenAIRE

    Pirola, Ilenia; Formenti, Anna M.; Gandossi, Elena; Mittempergher, Francesco; Casella, Claudio; Agosti, Barbara; Cappelli, Carlo

    2013-01-01

    Drug malabsorption is a potential concern after bariatric surgery. We present four case reports of hypothyroid patients who were well replaced with thyroxine tablets to euthyroid thyrotropin (TSH) levels prior to Roux-en-Y gastric bypass surgery. These patients developed elevated TSH levels after the surgery, the TSH responded reversibly to switching from treatment with oral tablets to a liquid formulation.

  10. Reduced variation of tracer binding in digoxin radioimmunoassay by use of 125I-labeled tyrosine--methyl-ester derivative: relation of thyroxine concentration to binding

    International Nuclear Information System (INIS)

    Between-sample variation in tracer binding in the 125I-labeled digoxin radioimmunoassay was investigated with two tracers, 3-0-succinyl-digoxigenin-[125I]-labeled tyrosine and [125I]-labeled tyrosine-methyl-ester-digoxin. Digoxin-free serum samples having various concentrations of thyroxine were assayed with both tracers. The percentage of tracer bound when the samples were assayed with the first-mentioned tracer was increased significantly for the low thyroxine groups when compared to the normal (P less than 0.001) or the high thyroxine groups (P less than 0.05). Little difference existed when the latter tracer was used. There was variation in tracer binding when serum from dogs dosed with thyrotropin was assayed with the first tracer, but there was little variation with the second. Tracer binding may be influenced by thyroxine-binding proteins. Variation in tracer binding appears to be reduced when [125I]-labeled tyrosine-methyl-ester-digoxin is used

  11. Developmental Triclosan Exposure Decreases Maternal,Fetal, and Early Neonatal Thyroxine: Dynamic and Kinetic Data Support for a Mode-of-Action

    Science.gov (United States)

    This work tests the mode-of-action (MOA) hypothesis that perinatal triclosan (TCS) exposure decreases circulating thyroxine (T4) concentrations via activation of pregnane X and/or constitutive androstane receptors (PXR, CAR), resulting in up-regulation of hepatic catabolism and e...

  12. Intracellular pH of brown adipose tissue increases during norepinephrine stimulation of thermogenesis

    International Nuclear Information System (INIS)

    Norepinephrine (NE) activation of brown fat (BAT) thermogenesis appears to involve dissociation of purine nucleotides from the mitochondrial uncoupling protein, resulting in release of normal respiratory control and enhanced substrate oxidation. Since the affinity of the uncoupling protein for purine nucleotides decreases significantly with increasing pH, the authors wished to determine if NE administration shifted the intracellular pH of BAT. To examine this question under in vivo conditions, they positioned a nuclear magnetic resonance (NMR) surface coil over the interscapular BAT of anesthetized male Syrian hamsters. The underlying and surrounding musculature was shielded to minimize their contribution to the 31P spectra. The hamster was placed in a Nicolet 200 Mhz spectrometer, operating in the Fourier Transform mode and tuned to 31P. Scans taken during infusion of ascorbate buffer (vehicle for NE) were compared to those taken during NE infusion (8 ng/g x min). During this infusion, BAT temperature increased 3.7 +/- 0.50C, confirming that BAT thermogenesis was activated. There also occurred a statistically significant PPM (parts per million) shift, averaging 0.070 +/- 0.022 (n = 22) and corresponding to an increase of approximately 0.07 pH units. This shift in intracellular pH from 7.32 to 7.39, although small, would facilitate the maintenance of loosely coupled brown fat mitochondria

  13. Intracellular pH of brown adipose tissue increases during norepinephrine stimulation of thermogenesis

    Energy Technology Data Exchange (ETDEWEB)

    Horwitz, B.A.; Hamilton, J.S.

    1986-03-01

    Norepinephrine (NE) activation of brown fat (BAT) thermogenesis appears to involve dissociation of purine nucleotides from the mitochondrial uncoupling protein, resulting in release of normal respiratory control and enhanced substrate oxidation. Since the affinity of the uncoupling protein for purine nucleotides decreases significantly with increasing pH, the authors wished to determine if NE administration shifted the intracellular pH of BAT. To examine this question under in vivo conditions, they positioned a nuclear magnetic resonance (NMR) surface coil over the interscapular BAT of anesthetized male Syrian hamsters. The underlying and surrounding musculature was shielded to minimize their contribution to the /sup 31/P spectra. The hamster was placed in a Nicolet 200 Mhz spectrometer, operating in the Fourier Transform mode and tuned to /sup 31/P. Scans taken during infusion of ascorbate buffer (vehicle for NE) were compared to those taken during NE infusion (8 ng/g x min). During this infusion, BAT temperature increased 3.7 +/- 0.5/sup 0/C, confirming that BAT thermogenesis was activated. There also occurred a statistically significant PPM (parts per million) shift, averaging 0.070 +/- 0.022 (n = 22) and corresponding to an increase of approximately 0.07 pH units. This shift in intracellular pH from 7.32 to 7.39, although small, would facilitate the maintenance of loosely coupled brown fat mitochondria.

  14. Epicardial fat volume assessment in cardiac CT

    OpenAIRE

    Coppini, Giuseppe; Favilla, Riccardo; Moroni, Davide; Salvetti, Ovidio; D'Errico, Luigina; Salituri, F; Ciardetti, Marco; Schlueter, Mathis; Faggioni, Luca; Coceani, Michele; Mazzarisi, Alessandro; M. Bianchi; Bartolozzi, C; Marraccini, Paolo

    2012-01-01

    Epicardial fat, as other visceral fat localizations, is correlated with car- diovascular disease, cardiovascular risk factors and metabolic syndrome. However, many concerns remain about the method for measuring epi- cardial fat, its regional distribution on the myocardium, as well as the accuracy and reproducibility of such measurements. At present, dedi- cated software procedures to assess epicardial fat are lacking. On the other hand, manual fat segmentation requires a huge and tedious oper...

  15. Autologous Fat Injection for Augmented Mammoplasty

    International Nuclear Information System (INIS)

    Autologous fat injection is one of the methods utilized for augmented mammoplasty methods. In this surgical procedure, the fat for transfer is obtained from the donor site of the patient's own body by liposuction and the fat is then injected into the breast. We report here cases of three patients who underwent autologous fat injection. Two of the patients had palpable masses that were present after surgery. The serial imaging findings and surgical method of autologous fat transfer are demonstrated

  16. Autologous Fat Injection for Augmented Mammoplasty

    Energy Technology Data Exchange (ETDEWEB)

    Yoon, Eul Sik; Seo, Bo Kyoung; Yi, Ann; Cho, Kyu Ran [Korea University Ansan Hospital, Ansan (Korea, Republic of)

    2008-12-15

    Autologous fat injection is one of the methods utilized for augmented mammoplasty methods. In this surgical procedure, the fat for transfer is obtained from the donor site of the patient's own body by liposuction and the fat is then injected into the breast. We report here cases of three patients who underwent autologous fat injection. Two of the patients had palpable masses that were present after surgery. The serial imaging findings and surgical method of autologous fat transfer are demonstrated

  17. Intravitreally Injected Anti-VEGF Antibody Reduces Brown Fat in Neonatal Mice

    OpenAIRE

    Jo, D.H.; Park, S W; Cho, C S; Powner, M. B.; Fruttiger, M; Kim, J. H.

    2015-01-01

    Anti-vascular endothelial growth factor (VEGF) agents are the mainstay treatment for various angiogenesis-related retinal diseases. Currently, bevacizumab, a recombinant humanized anti-VEGF antibody, is trailed in retinopathy of prematurity, a vasoproliferative retinal disorder in premature infants. However, the risks of systemic complications after intravitreal injection of anti-VEGF antibody in infants are not well understood. In this study, we show that intravitreally injected anti-VEGF an...

  18. Perilipin overexpression in white adipose tissue induces a brown fat-like phenotype

    Science.gov (United States)

    BACKGROUND: Perilipin A (PeriA) exclusively locates on adipocyte lipid droplets and is essential for lipid storage and lipolysis. Previously, we reported that adipocyte specific overexpression of PeriA caused resistance to diet-induced obesity and resulted in improved insulin sensitivity. In order...

  19. Dicer1-miR-328-Bace1 signalling controls brown adipose tissue differentiation and function.

    Science.gov (United States)

    Oliverio, Matteo; Schmidt, Elena; Mauer, Jan; Baitzel, Catherina; Hansmeier, Nils; Khani, Sajjad; Konieczka, Sandra; Pradas-Juni, Marta; Brodesser, Susanne; Van, Trieu-My; Bartsch, Deniz; Brönneke, Hella S; Heine, Markus; Hilpert, Hans; Tarcitano, Emilio; Garinis, George A; Frommolt, Peter; Heeren, Joerg; Mori, Marcelo A; Brüning, Jens C; Kornfeld, Jan-Wilhelm

    2016-03-01

    Activation of brown adipose tissue (BAT) controls energy homeostasis in rodents and humans and has emerged as an innovative strategy for the treatment of obesity and type 2 diabetes mellitus. Here we show that ageing- and obesity-associated dysfunction of brown fat coincides with global microRNA downregulation due to reduced expression of the microRNA-processing node Dicer1. Consequently, heterozygosity of Dicer1 in BAT aggravated diet-induced-obesity (DIO)-evoked deterioration of glucose metabolism. Analyses of differential microRNA expression during preadipocyte commitment and mouse models of progeria, longevity and DIO identified miR-328 as a regulator of BAT differentiation. Reducing miR-328 blocked preadipocyte commitment, whereas miR-328 overexpression instigated BAT differentiation and impaired muscle progenitor commitment-partly through silencing of the β-secretase Bace1. Loss of Bace1 enhanced brown preadipocyte specification in vitro and was overexpressed in BAT of obese and progeroid mice. In vivo Bace1 inhibition delayed DIO-induced weight gain and improved glucose tolerance and insulin sensitivity. These experiments reveal Dicer1-miR-328-Bace1 signalling as a determinant of BAT function, and highlight the potential of Bace1 inhibition as a therapeutic approach to improve not only neurodegenerative diseases but also ageing- and obesity-associated impairments of BAT function. PMID:26900752

  20. Berardinelli-Seip congenital lipodystrophy 2 regulates adipocyte lipolysis, browning, and energy balance in adult animals.

    Science.gov (United States)

    Zhou, Hongyi; Lei, Xinnuo; Benson, Tyler; Mintz, James; Xu, Xiaojing; Harris, Ruth B; Weintraub, Neal L; Wang, Xiaoling; Chen, Weiqin

    2015-10-01

    Mutations in BSCL2/SEIPIN cause Berardinelli-Seip congenital lipodystrophy type 2 (BSCL2), but the mechanisms whereby Bscl2 regulates adipose tissue function are unclear. Here, we generated adipose tissue (mature) Bscl2 knockout (Ad-mKO) mice, in which Bscl2 was specifically ablated in adipocytes of adult animals, to investigate the impact of acquired Bscl2 deletion on adipose tissue function and energy balance. Ad-mKO mice displayed reduced adiposity and were protected against high fat diet-induced obesity, but not insulin resistance or hepatic steatosis. Gene expression profiling and biochemical assays revealed increased lipolysis and fatty acid oxidation in white adipose tissue (WAT) and brown adipose tissue , as well as browning of WAT, owing to induction of cAMP/protein kinase A signaling upon Bscl2 deletion. Interestingly, Bscl2 deletion reduced food intake and downregulated adipose β3-adrenergic receptor (ADRB3) expression. Impaired ADRB3 signaling partially offsets upregulated browning-induced energy expenditure and thermogenesis in Ad-mKO mice housed at ambient temperature. However, this counter-regulatory response was abrogated under thermoneutral conditions, resulting in even greater body mass loss in Ad-mKO mice. These findings suggest that Bscl2 regulates adipocyte lipolysis and β-adrenergic signaling to produce complex effects on adipose tissues and whole-body energy balance. PMID:26269358