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Sample records for coactivator 1alpha pgc-1alpha

  1. Transcriptional co-activator PGC-1 alpha drives the formation of slow-twitch muscle fibres.

    Science.gov (United States)

    Lin, Jiandie; Wu, Hai; Tarr, Paul T; Zhang, Chen-Yu; Wu, Zhidan; Boss, Olivier; Michael, Laura F; Puigserver, Pere; Isotani, Eiji; Olson, Eric N; Lowell, Bradford B; Bassel-Duby, Rhonda; Spiegelman, Bruce M

    2002-08-15

    The biochemical basis for the regulation of fibre-type determination in skeletal muscle is not well understood. In addition to the expression of particular myofibrillar proteins, type I (slow-twitch) fibres are much higher in mitochondrial content and are more dependent on oxidative metabolism than type II (fast-twitch) fibres. We have previously identified a transcriptional co-activator, peroxisome-proliferator-activated receptor-gamma co-activator-1 (PGC-1 alpha), which is expressed in several tissues including brown fat and skeletal muscle, and that activates mitochondrial biogenesis and oxidative metabolism. We show here that PGC-1 alpha is expressed preferentially in muscle enriched in type I fibres. When PGC-1 alpha is expressed at physiological levels in transgenic mice driven by a muscle creatine kinase (MCK) promoter, a fibre type conversion is observed: muscles normally rich in type II fibres are redder and activate genes of mitochondrial oxidative metabolism. Notably, putative type II muscles from PGC-1 alpha transgenic mice also express proteins characteristic of type I fibres, such as troponin I (slow) and myoglobin, and show a much greater resistance to electrically stimulated fatigue. Using fibre-type-specific promoters, we show in cultured muscle cells that PGC-1 alpha activates transcription in cooperation with Mef2 proteins and serves as a target for calcineurin signalling, which has been implicated in slow fibre gene expression. These data indicate that PGC-1 alpha is a principal factor regulating muscle fibre type determination.

  2. Maintenance of Glucose Homeostasis through Acetylation of the Metabolic Transcriptional Coactivator PGC-1alpha

    National Research Council Canada - National Science Library

    Puigserver, Pere

    2008-01-01

    The main purpose of this proposal is to test the hypothesis that acetylation of PGC-1alpha by GCN5 and associated proteins, Pc3 and WDR18, is a key regulatory modification that controls hepatic glucose production...

  3. Maintenance of Glucose Homeostasis through Acetylation of the Metabolic Transcriptional Coactivator PGC-1alpha

    National Research Council Canada - National Science Library

    Puigserver, Pere

    2007-01-01

    ... hepatic glucose production. This investigation has a define scope to specifically test how these proteins control the acetylation status of PGC-1alpha and what is the functional effect in blood glucose levels...

  4. Studies of the Gly482Ser polymorphism of the peroxisome proliferator-activated receptor gamma coactivator 1alpha (PGC-1alpha) gene in Danish subjects with the metabolic syndrome

    DEFF Research Database (Denmark)

    Ambye, L; Rasmussen, S; Fenger, Mogens

    2005-01-01

    The peroxisome proliferator-activated receptor gamma co-activator 1alpha (PGC-1alpha) is a novel transcriptional co-activator that holds an important role in lipid and glucose metabolism. PGC-1alpha is a candidate gene for the metabolic syndrome (MS) as well as type 2 diabetes. Recent studies...... related to this syndrome. The variant was examined, using PCR-RFLP, in the DanMONICA cohort comprising a population-based sample of 2349 subjects. MS was defined using the National Cholesterol Education Program -- Adult Treatment Panel III (NCEP-ATPIII) criteria. The allelic frequency of the Ser482 allele...... and insulin secretion, 24-ambulatory blood pressure or left ventricular mass index. In conclusion, the Gly482Ser polymorphism of the PGC-1alpha gene is not associated with the metabolic syndrome, related quantitative traits or cardiac hypertrophy among Danish Caucasian subjects...

  5. Calcineurin signaling and PGC-1alpha expression are suppressed during muscle atrophy due to diabetes.

    Science.gov (United States)

    Roberts-Wilson, Tiffany K; Reddy, Ramesh N; Bailey, James L; Zheng, Bin; Ordas, Ronald; Gooch, Jennifer L; Price, S Russ

    2010-08-01

    PGC-1alpha is a transcriptional coactivator that controls energy homeostasis through regulation of glucose and oxidative metabolism. Both PGC-1alpha expression and oxidative capacity are decreased in skeletal muscle of patients and animals undergoing atrophy, suggesting that PGC-1alpha participates in the regulation of muscle mass. PGC-1alpha gene expression is controlled by calcium- and cAMP-sensitive pathways. However, the mechanism regulating PGC-1alpha in skeletal muscle during atrophy remains unclear. Therefore, we examined the mechanism responsible for decreased PGC-1alpha expression using a rodent streptozotocin (STZ) model of chronic diabetes and atrophy. After 21days, the levels of PGC-1alpha protein and mRNA were decreased. We examined the activation state of CREB, a potent activator of PGC-1alpha transcription, and found that phospho-CREB was paradoxically high in muscle of STZ-rats, suggesting that the cAMP pathway was not involved in PGC-1alpha regulation. In contrast, expression of calcineurin (Cn), a calcium-dependent phosphatase, was suppressed in the same muscles. PGC-1alpha expression is regulated by two Cn substrates, MEF2 and NFATc. Therefore, we examined MEF2 and NFATc activity in muscles from STZ-rats. Target genes MRF4 and MCIP1.4 mRNAs were both significantly reduced, consistent with reduced Cn signaling. Moreover, levels of MRF4, MCIP1.4, and PGC-1alpha were also decreased in muscles of CnAalpha-/- and CnAbeta-/- mice without diabetes indicating that decreased Cn signaling, rather than changes in other calcium- or cAMP-sensitive pathways, were responsible for decreased PGC-1alpha expression. These findings demonstrate that Cn activity is a major determinant of PGC-1alpha expression in skeletal muscle during diabetes and possibly other conditions associated with loss of muscle mass.

  6. PGC-1alpha Deficiency Causes Multi-System Energy Metabolic Derangements: Muscle Dysfunction, Abnormal Weight Control and Hepatic Steatosis

    Directory of Open Access Journals (Sweden)

    Leone Teresa C

    2005-01-01

    Full Text Available The gene encoding the transcriptional coactivator peroxisome proliferator-activated receptor-gamma coactivator-1alpha (PGC-1alpha was targeted in mice. PGC-1alpha null (PGC-1alpha-/- mice were viable. However, extensive phenotyping revealed multi-system abnormalities indicative of an abnormal energy metabolic phenotype. The postnatal growth of heart and slow-twitch skeletal muscle, organs with high mitochondrial energy demands, is blunted in PGC-1alpha-/- mice. With age, the PGC-1alpha-/- mice develop abnormally increased body fat, a phenotype that is more severe in females. Mitochondrial number and respiratory capacity is diminished in slow-twitch skeletal muscle of PGC-1alpha-/- mice, leading to reduced muscle performance and exercise capacity. PGC-1alpha-/- mice exhibit a modest diminution in cardiac function related largely to abnormal control of heart rate. The PGC-1alpha-/- mice were unable to maintain core body temperature following exposure to cold, consistent with an altered thermogenic response. Following short-term starvation, PGC-1alpha-/- mice develop hepatic steatosis due to a combination of reduced mitochondrial respiratory capacity and an increased expression of lipogenic genes. Surprisingly, PGC-1alpha-/- mice were less susceptible to diet-induced insulin resistance than wild-type controls. Lastly, vacuolar lesions were detected in the central nervous system of PGC-1alpha-/- mice. These results demonstrate that PGC-1alpha is necessary for appropriate adaptation to the metabolic and physiologic stressors of postnatal life.

  7. PGC-1alpha deficiency causes multi-system energy metabolic derangements: muscle dysfunction, abnormal weight control and hepatic steatosis.

    Directory of Open Access Journals (Sweden)

    Teresa C Leone

    2005-04-01

    Full Text Available The gene encoding the transcriptional coactivator peroxisome proliferator-activated receptor-gamma coactivator-1alpha (PGC-1alpha was targeted in mice. PGC-1alpha null (PGC-1alpha(-/- mice were viable. However, extensive phenotyping revealed multi-system abnormalities indicative of an abnormal energy metabolic phenotype. The postnatal growth of heart and slow-twitch skeletal muscle, organs with high mitochondrial energy demands, is blunted in PGC-1alpha(-/- mice. With age, the PGC-1alpha(-/- mice develop abnormally increased body fat, a phenotype that is more severe in females. Mitochondrial number and respiratory capacity is diminished in slow-twitch skeletal muscle of PGC-1alpha(-/- mice, leading to reduced muscle performance and exercise capacity. PGC-1alpha(-/- mice exhibit a modest diminution in cardiac function related largely to abnormal control of heart rate. The PGC-1alpha(-/- mice were unable to maintain core body temperature following exposure to cold, consistent with an altered thermogenic response. Following short-term starvation, PGC-1alpha(-/- mice develop hepatic steatosis due to a combination of reduced mitochondrial respiratory capacity and an increased expression of lipogenic genes. Surprisingly, PGC-1alpha(-/- mice were less susceptible to diet-induced insulin resistance than wild-type controls. Lastly, vacuolar lesions were detected in the central nervous system of PGC-1alpha(-/- mice. These results demonstrate that PGC-1alpha is necessary for appropriate adaptation to the metabolic and physiologic stressors of postnatal life.

  8. Identification and characterization of an alternative promoter of the human PGC-1{alpha} gene

    Energy Technology Data Exchange (ETDEWEB)

    Yoshioka, Toyo; Inagaki, Kenjiro [Division of Diabetes, Metabolism, and Endocrinology, Department of Internal Medicine, Kobe University Graduate School of Medicine, 7-5-1 Kusunoki-cho, Chuo-ku, Kobe 650-0017 (Japan); Noguchi, Tetsuya, E-mail: noguchi@med.kobe-u.ac.jp [Division of Diabetes, Metabolism, and Endocrinology, Department of Internal Medicine, Kobe University Graduate School of Medicine, 7-5-1 Kusunoki-cho, Chuo-ku, Kobe 650-0017 (Japan); Sakai, Mashito; Ogawa, Wataru; Hosooka, Tetsuya [Division of Diabetes, Metabolism, and Endocrinology, Department of Internal Medicine, Kobe University Graduate School of Medicine, 7-5-1 Kusunoki-cho, Chuo-ku, Kobe 650-0017 (Japan); Iguchi, Haruhisa; Watanabe, Eijiro; Matsuki, Yasushi; Hiramatsu, Ryuji [Genomic Science Laboratories, DainipponSumitomo Pharma Co. Ltd., 4-2-1 Takatsukasa, Takarazuka 665-8555 (Japan); Kasuga, Masato [Division of Diabetes, Metabolism, and Endocrinology, Department of Internal Medicine, Kobe University Graduate School of Medicine, 7-5-1 Kusunoki-cho, Chuo-ku, Kobe 650-0017 (Japan); Research Institute, International Medical Center of Japan, 1-21-1 Toyama, Shinjuku-ku, Tokyo 162-8655 (Japan)

    2009-04-17

    The transcriptional regulator peroxisome proliferator-activated receptor-{gamma} coactivator-1{alpha} (PGC-1{alpha}) controls mitochondrial biogenesis and energy homeostasis. Although physical exercise induces PGC-1{alpha} expression in muscle, the underlying mechanism of this effect has remained incompletely understood. We recently identified a novel muscle-enriched isoform of PGC-1{alpha} transcript (designated PGC-1{alpha}-b) that is derived from a previously unidentified first exon. We have now cloned and characterized the human PGC-1{alpha}-b promoter. The muscle-specific transcription factors MyoD and MRF4 transactivated this promoter through interaction with a proximal E-box motif. Furthermore, either forced expression of Ca{sup 2+}- and calmodulin-dependent protein kinase IV (CaMKIV), calcineurin A, or the p38 mitogen-activated protein kinase (p38 MAPK) kinase MKK6 or the intracellular accumulation of cAMP activated the PGC-1{alpha}-b promoter in cultured myoblasts through recruitment of cAMP response element (CRE)-binding protein (CREB) to a putative CRE located downstream of the E-box. Our results thus reveal a potential molecular basis for isoform-specific regulation of PGC-1{alpha} expression in contracting muscle.

  9. PGC-1{alpha} accelerates cytosolic Ca{sup 2+} clearance without disturbing Ca{sup 2+} homeostasis in cardiac myocytes

    Energy Technology Data Exchange (ETDEWEB)

    Chen, Min, E-mail: chenminyx@gmail.com [Institute of Molecular Medicine, State Key Laboratory of Biomembrane and Membrane Biotechnology, Peking University, Beijing 100871 (China); Yunnan Centers for Diseases Prevention and Control, Kunming 650022 (China); Wang, Yanru [Institute of Molecular Medicine, State Key Laboratory of Biomembrane and Membrane Biotechnology, Peking University, Beijing 100871 (China); Qu, Aijuan [Laboratory of Metabolism, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, MD 20892 (United States)

    2010-06-11

    Energy metabolism and Ca{sup 2+} handling serve critical roles in cardiac physiology and pathophysiology. Peroxisome proliferator-activated receptor gamma coactivator 1 alpha (PGC-1{alpha}) is a multi-functional coactivator that is involved in the regulation of cardiac mitochondrial functional capacity and cellular energy metabolism. However, the regulation of PGC-1{alpha} in cardiac Ca{sup 2+} signaling has not been fully elucidated. To address this issue, we combined confocal line-scan imaging with off-line imaging processing to characterize calcium signaling in cultured adult rat ventricular myocytes expressing PGC-1{alpha} via adenoviral transduction. Our data shows that overexpressing PGC-1{alpha} improved myocyte contractility without increasing the amplitude of Ca{sup 2+} transients, suggesting that myofilament sensitivity to Ca{sup 2+} increased. Interestingly, the decay kinetics of global Ca{sup 2+} transients and Ca{sup 2+} waves accelerated in PGC-1{alpha}-expressing cells, but the decay rate of caffeine-elicited Ca{sup 2+} transients showed no significant change. This suggests that sarcoplasmic reticulum (SR) Ca{sup 2+}-ATPase (SERCA2a), but not Na{sup +}/Ca{sup 2+} exchange (NCX) contribute to PGC-1{alpha}-induced cytosolic Ca{sup 2+} clearance. Furthermore, PGC-1{alpha} induced the expression of SERCA2a in cultured cardiac myocytes. Importantly, overexpressing PGC-1{alpha} did not disturb cardiac Ca{sup 2+} homeostasis, because SR Ca{sup 2+} load and the propensity for Ca{sup 2+} waves remained unchanged. These data suggest that PGC-1{alpha} can ameliorate cardiac Ca{sup 2+} cycling and improve cardiac work output in response to physiological stress. Unraveling the PGC-1{alpha}-calcium handing pathway sheds new light on the role of PGC-1{alpha} in the therapy of cardiac diseases.

  10. Coordinated balancing of muscle oxidative metabolism through PGC-1{alpha} increases metabolic flexibility and preserves insulin sensitivity

    Energy Technology Data Exchange (ETDEWEB)

    Summermatter, Serge [Biozentrum, Division of Pharmacology/Neurobiology, University of Basel, Klingelbergstrasse 50-70, CH-4056 Basel (Switzerland); Troxler, Heinz [Division of Clinical Chemistry and Biochemistry, Department of Pediatrics, University Children' s Hospital, University of Zurich, Steinwiesstrasse 75, CH-8032 Zurich (Switzerland); Santos, Gesa [Biozentrum, Division of Pharmacology/Neurobiology, University of Basel, Klingelbergstrasse 50-70, CH-4056 Basel (Switzerland); Handschin, Christoph, E-mail: christoph.handschin@unibas.ch [Biozentrum, Division of Pharmacology/Neurobiology, University of Basel, Klingelbergstrasse 50-70, CH-4056 Basel (Switzerland)

    2011-04-29

    Highlights: {yields} PGC-1{alpha} enhances muscle oxidative capacity. {yields} PGC-1{alpha} promotes concomitantly positive and negative regulators of lipid oxidation. {yields} Regulator abundance enhances metabolic flexibility and balances oxidative metabolism. {yields} Balanced oxidation prevents detrimental acylcarnitine and ROS generation. {yields} Absence of detrimental metabolites preserves insulin sensitivity -- Abstract: The peroxisome proliferator-activated receptor {gamma} coactivator 1{alpha} (PGC-1{alpha}) enhances oxidative metabolism in skeletal muscle. Excessive lipid oxidation and electron transport chain activity can, however, lead to the accumulation of harmful metabolites and impair glucose homeostasis. Here, we investigated the effect of over-expression of PGC-1{alpha} on metabolic control and generation of insulin desensitizing agents in extensor digitorum longus (EDL), a muscle that exhibits low levels of PGC-1{alpha} in the untrained state and minimally relies on oxidative metabolism. We demonstrate that PGC-1{alpha} induces a strictly balanced substrate oxidation in EDL by concomitantly promoting the transcription of activators and inhibitors of lipid oxidation. Moreover, we show that PGC-1{alpha} enhances the potential to uncouple oxidative phosphorylation. Thereby, PGC-1{alpha} boosts elevated, yet tightly regulated oxidative metabolism devoid of side products that are detrimental for glucose homeostasis. Accordingly, PI3K activity, an early phase marker for insulin resistance, is preserved in EDL muscle. Our findings suggest that PGC-1{alpha} coordinately coactivates the simultaneous transcription of gene clusters implicated in the positive and negative regulation of oxidative metabolism and thereby increases metabolic flexibility. Thus, in mice fed a normal chow diet, over-expression of PGC-1{alpha} does not alter insulin sensitivity and the metabolic adaptations elicited by PGC-1{alpha} mimic the beneficial effects of endurance training

  11. The role of PGC-1alpha on mitochondrial function and apoptotic susceptibility in muscle

    DEFF Research Database (Denmark)

    Adhihetty, Peter J; Uguccioni, Giulia; Leick, Lotte

    2009-01-01

    Mitochondria are critical for cellular bioenergetics, and they mediate apoptosis within cells. We used whole body peroxisome proliferator-activated receptor-gamma coactivator-1alpha (PGC-1alpha) knockout (KO) animals to investigate its role on organelle function, apoptotic signaling, and cytochrome......-c oxidase activity, an indicator of mitochondrial content, in muscle and other tissues (brain, liver, and pancreas). Lack of PGC-1alpha reduced mitochondrial content in all muscles (17-44%; P liver, and pancreas. However, the tissue expression of proteins involved...

  12. PGC-1{alpha} is required for AICAR induced expression of GLUT4 and mitochondrial proteins in mouse skeletal muscle

    DEFF Research Database (Denmark)

    Leick, Lotte; Fentz, Joachim; Biensø, Rasmus S

    2010-01-01

    We tested the hypothesis that repeated activation of AMPK induces mitochondrial and glucose membrane transporter gene/protein expression via a peroxisome proliferator activated receptor Upsilon co-activator (PGC)-1alpha dependent mechanism. Whole body PGC-1alpha knockout (KO) and littermate wild...... GLUT4, cytochrome c oxidase (COX)I and cytochrome (cyt) c protein expression ~10-40% relative to saline in white muscles of the WT mice, but not of the PGC-1alpha KO mice. In line, GLUT4 and cyt c mRNA content increased 30-60% 4h after a single AICAR injection relative to saline only in WT mice. One...... and PGC-1alpha KO mice. In conclusion, we here provide genetic evidence for a major role of PGC-1alpha in AMPK mediated regulation of mitochondrial and glucose membrane transport protein expression in skeletal muscle....

  13. PGC-1alpha is not mandatory for exercise- and training-induced adaptive gene responses in mouse skeletal muscle

    DEFF Research Database (Denmark)

    Leick, Lotte; Wojtaszewski, Jørgen F P; Johansen, Sune T.

    2008-01-01

    The aim of the present study was to test the hypothesis that peroxisome proliferator activated receptor-gamma coactivator (PGC) 1alpha is required for exercise-induced adaptive gene responses in skeletal muscle. Whole body PGC-1alpha knockout (KO) and littermate wild-type (WT) mice performed....... Resting muscles of the PGC-1alpha KO mice had lower ( approximately 20%) cytochrome c (cyt c), cytochrome oxidase (COX) I, and aminolevulinate synthase (ALAS) 1 mRNA and protein levels than WT, but similar levels of AMP-activated protein kinase (AMPK) alpha1, AMPKalpha2, and hexokinase (HK) II compared...

  14. NMDA receptor dependent PGC-1alpha up-regulation protects the cortical neuron against oxygen-glucose deprivation/reperfusion injury.

    Science.gov (United States)

    Luo, Yun; Zhu, Wenjing; Jia, Jia; Zhang, Chenyu; Xu, Yun

    2009-09-01

    The peroxisome proliferator activated receptor coactivator 1 alpha (PGC-1alpha) is a nuclear transcriptional coactivator that is widely expressed in the brain areas. Over-expression of PGC-1alpha can protect neuronal cells from oxidant-induced injury. The purpose of the current study is to investigate the role of PGC-1alpha in the oxygen (anoxia) deprivation (OGD) neurons. The PGC-1alpha mRNA and protein level between control and OGD neurons were examined by real-time PCR and Western blot. More PGC-1alpha expression was found in the OGD neurons compared with the normal group. Over-expression of PGC-1alpha suppressed cell apoptosis while inhibition of the PGC-1alpha expression induced cell apoptosis in OGD neurons. Furthermore, increase of PGC-1alpha resulted in activation of N-methyl-D-aspartate (NMDA) receptor, p38, and ERK mitogen-activated protein kinase (MAPK) pathway. The blocking of the NMDA receptor by its antagonists MK-801 reduced PGC-1alpha mRNA expression in OGD neurons, while NMDA itself can directly induce the expression of PGC-1alpha in neuronal cells. At the same time, PD98059 (ERK MAPK inhibitor) and SB203580 (P38 MAPK inhibitor) also prevented the up-regulation of PGC-1alpha in OGD neurons and MK801 can inhibit the expression of P38 and ERK MAPK. These data suggested that the expression of PGC-1alpha was up-regulated in OGD mice cortical neurons, which protected the neurons against OGD injury. Moreover, this effect was correlated to the NMDA receptor and the ERK and P38 MAPK pathway. The protective effect of PGC-1alpha on OGD cortical neurons may be useful for stroke therapy.

  15. Quantitative immuno-electron microscopic analysis of depolarization-induced expression of PGC-1alpha in cultured rat visual cortical neurons.

    Science.gov (United States)

    Meng, Hui; Liang, Huan Ling; Wong-Riley, Margaret

    2007-10-17

    Peroxisome proliferator-activated receptor-gamma coactivator 1alpha (PGC- 1alpha) is a coactivator of nuclear receptors and other transcription factors that regulate several metabolic processes, including mitochondrial biogenesis, energy homeostasis, respiration, and gluconeogenesis. PGC-1alpha plays a vital role in stimulating genes that are important to oxidative metabolism and other mitochondrial functions in brown adipose tissue and skeleton muscles, but the significance of PGC-1alpha in the brain remains elusive. The goal of our present study was to determine by means of quantitative immuno-electron microscopy the expression of PGC-1alpha in cultured rat visual cortical neurons under normal conditions as well as after depolarizing stimulation for varying periods of time. Our results showed that: (a) PGC-1alpha was normally located in both the nucleus and the cytoplasm. In the nucleus, PGC-1alpha was associated mainly with euchromatin rather than heterochromatin, consistent with active involvement in transcription. In the cytoplasm, it was associated mainly with free ribosomes. (b) Neuronal depolarization by KCl for 0.5 h induced a significant increase in PGC-1alpha labeling density in both the nucleus and the cytoplasm (Pneuronal activity by synthesizing more proteins in the cytoplasm and translocating them to the nucleus for gene activation. PGC-1alpha level in neurons is, therefore, tightly regulated by neuronal activity.

  16. PGC-1alpha and PGC-1beta have both similar and distinct effects on myofiber switching toward an oxidative phenotype

    DEFF Research Database (Denmark)

    Mortensen, Ole Hartvig; Frandsen, Lis; Schjerling, Peter

    2006-01-01

    Peroxisome proliferator-activated receptor-gamma coactivator-1alpha and -1beta (PGC-1alpha and PGC-1beta) were overexpressed by adenovirus-mediated gene transfer in cultures of primary rat skeletal muscle cells derived from neonatal myoblasts. Effects on muscle fiber type transition and metabolism...... an increase in the mRNA expression of TRB3, a negative regulator of insulin signaling. These results show that both PGC-1alpha and PGC-1beta are involved in the regulation of skeletal muscle fiber transition and metabolism and that they have both overlapping and differing effects....... were studied from days 5 to 22 of culture. PGC-1alpha and PGC-1beta overexpression caused a three- to fourfold increase in mRNA level, a doubling of enzymatic activity of citrate synthase, a slight increase in short-chain acyl-CoA dehydrogenase mRNA, a doubling of the mRNA level, and a 30-50% increase...

  17. Studies of the Gly482Ser polymorphism of the peroxisome proliferator-activated receptor gamma coactivator 1alpha (PGC-1alpha) gene in Danish subjects with the metabolic syndrome

    DEFF Research Database (Denmark)

    Ambye, Louise; Rasmussen, Susanne; Fenger, Mogens

    2005-01-01

    related to this syndrome. The variant was examined, using PCR-RFLP, in the DanMONICA cohort comprising a population-based sample of 2349 subjects. MS was defined using the National Cholesterol Education Program -- Adult Treatment Panel III (NCEP-ATPIII) criteria. The allelic frequency of the Ser482 allele...... and insulin secretion, 24-ambulatory blood pressure or left ventricular mass index. In conclusion, the Gly482Ser polymorphism of the PGC-1alpha gene is not associated with the metabolic syndrome, related quantitative traits or cardiac hypertrophy among Danish Caucasian subjects...

  18. PGC-1alpha Gly482Ser polymorphism associates with hypertension among Danish whites

    DEFF Research Database (Denmark)

    Andersen, Gitte; Wegner, Lise; Jensen, Dorit Packert

    2005-01-01

    in combination with previously published results. The Ser/Ser genotype was significantly associated with a reduced risk of hypertension and with lower systolic, diastolic, and mean arterial blood pressure levels, predominantly among women. Finally, in a combined analysis using data obtained in both sexes...... to elucidate the differential role of this polymorphism in men and women.......PGC-1alpha is a coactivator of numerous transcription factors and is expressed in tissues with high energy demands and abundant in mitochondria. It is induced in the myocardium on fasting and physical exercise, and cardiac-specific overexpression stimulates mitochondrial biogenesis in mice...

  19. Sirtuin 3, a new target of PGC-1alpha, plays an important role in the suppression of ROS and mitochondrial biogenesis.

    Directory of Open Access Journals (Sweden)

    Xingxing Kong

    2010-07-01

    Full Text Available Sirtuin 3 (SIRT3 is one of the seven mammalian sirtuins, which are homologs of the yeast Sir2 gene. SIRT3 is the only sirtuin with a reported association with the human life span. Peroxisome proliferator-activated receptor gamma coactivator-1alpha (PGC-1alpha plays important roles in adaptive thermogenesis, gluconeogenesis, mitochondrial biogenesis and respiration. PGC-1alpha induces several key reactive oxygen species (ROS-detoxifying enzymes, but the molecular mechanism underlying this is not well understood.Here we show that PGC-1alpha strongly stimulated mouse Sirt3 gene expression in muscle cells and hepatocytes. Knockdown of PGC-1alpha led to decreased Sirt3 gene expression. PGC-1alpha activated the mouse SIRT3 promoter, which was mediated by an estrogen-related receptor (ERR binding element (ERRE (-407/-399 mapped to the promoter region. Chromatin immunoprecipitation and electrophoretic mobility shift assays confirmed that ERRalpha bound to the identified ERRE and PGC-1alpha co-localized with ERRalpha in the mSirt3 promoter. Knockdown of ERRalpha reduced the induction of Sirt3 by PGC-1alpha in C(2C(12 myotubes. Furthermore, Sirt3 was essential for PGC-1alpha-dependent induction of ROS-detoxifying enzymes and several components of the respiratory chain, including glutathione peroxidase-1, superoxide dismutase 2, ATP synthase 5c, and cytochrome c. Overexpression of SIRT3 or PGC-1alpha in C(2C(12 myotubes decreased basal ROS level. In contrast, knockdown of mSIRT3 increased basal ROS level and blocked the inhibitory effect of PGC-1alpha on cellular ROS production. Finally, SIRT3 stimulated mitochondrial biogenesis, and SIRT3 knockdown decreased the stimulatory effect of PGC-1alpha on mitochondrial biogenesis in C(2C(12 myotubes.Our results indicate that Sirt3 functions as a downstream target gene of PGC-1alpha and mediates the PGC-1alpha effects on cellular ROS production and mitochondrial biogenesis. Thus, SIRT3 integrates cellular energy

  20. Protection against dexamethasone-induced muscle atrophy is related to modulation by testosterone of FOXO1 and PGC-1{alpha}

    Energy Technology Data Exchange (ETDEWEB)

    Qin, Weiping, E-mail: weiping.qin@mssm.edu [Center of Excellence for the Medical Consequences of Spinal Cord Injury, James J. Peters VA Medical Center, Bronx, NY (United States); Department of Medicine, Mount Sinai School of Medicine, NY (United States); Pan, Jiangping; Wu, Yong [Center of Excellence for the Medical Consequences of Spinal Cord Injury, James J. Peters VA Medical Center, Bronx, NY (United States); Bauman, William A. [Center of Excellence for the Medical Consequences of Spinal Cord Injury, James J. Peters VA Medical Center, Bronx, NY (United States); Department of Medicine, Mount Sinai School of Medicine, NY (United States); Department of Rehabilitation Medicine, Mount Sinai School of Medicine, NY (United States); Cardozo, Christopher, E-mail: Chris.Cardozo@mssm.edu [Center of Excellence for the Medical Consequences of Spinal Cord Injury, James J. Peters VA Medical Center, Bronx, NY (United States); Department of Medicine, Mount Sinai School of Medicine, NY (United States); Department of Rehabilitation Medicine, Mount Sinai School of Medicine, NY (United States)

    2010-12-17

    Research highlights: {yields} In rat gastrocnemius muscle, dexamethasone reduced PGC-1{alpha} cellular and nuclear levels without altering mRNA levels for this factor. {yields} Dexamethasone reduced phosphorylating of p38 MAPK, which stabilizes PGC-1{alpha} and promotes its nuclear entry. {yields} Co-administration of testosterone with dexamethasone increased cellular and nuclear levels of PGC-1{alpha} protein without changing its mRNA levels. {yields} Co-administration of testosterone restored p38 MAPK levels to those of controls. -- Abstract: Glucocorticoid-induced muscle atrophy results from muscle protein catabolism and reduced protein synthesis, associated with increased expression of two muscle-specific ubiquitin ligases (MAFbx and MuRF1), and of two inhibitors of protein synthesis, REDD1 and 4EBP1. MAFbx, MuRF1, REDD1 and 4EBP1 are up-regulated by the transcription factors FOXO1 and FOXO3A. The transcriptional co-activator PGC-1{alpha} has been shown to attenuate many forms of muscle atrophy and to repress FOXO3A-mediated transcription of atrophy-specific genes. Dexamethasone-induced muscle atrophy can be prevented by testosterone, which blocks up-regulation by dexamethasone of FOXO1. Here, an animal model of dexamethasone-induced muscle atrophy was used to further characterize effects of testosterone to abrogate adverse actions of dexamethasone on FOXO1 levels and nuclear localization, and to determine how these agents affect PGC-1{alpha}, and its upstream activators, p38 MAPK and AMPK. In rat gastrocnemius muscle, testosterone blunted the dexamethasone-mediated increase in levels of FOXO1 mRNA, and FOXO1 total and nuclear protein. Dexamethasone reduced total and nuclear PGC-1{alpha} protein levels in the gastrocnemius; co-administration of testosterone with dexamethasone increased total and nuclear PGC-1{alpha} levels above those present in untreated controls. Testosterone blocked dexamethasone-induced decreases in activity of p38 MAPK in the gastrocnemius

  1. PGC-1alpha mediates exercise-induced skeletal muscle VEGF expression in mice

    DEFF Research Database (Denmark)

    Leick, Lotte; Hellsten, Ylva; Fentz, Joachim

    2009-01-01

    The aim of the present study was to test the hypothesis that PGC-1alpha is required for exercise-induced VEGF expression in both young and old mice and that AMPK activation leads to increased VEGF expression through a PGC-1alpha-dependent mechanism. Whole body PGC-1alpha knockout (KO......) and littermate wild-type (WT) mice were submitted to either 1) 5 wk of exercise training, 2) lifelong (from 2 to 13 mo of age) exercise training in activity wheel, 3) a single exercise bout, or 4) 4 wk of daily subcutaneous AICAR or saline injections. In skeletal muscle of PGC-1alpha KO mice, VEGF protein...... expression was approximately 60-80% lower and the capillary-to-fiber ratio approximately 20% lower than in WT. Basal VEGF mRNA expression was similar in WT and PGC-1alpha KO mice, but acute exercise and AICAR treatment increased the VEGF mRNA content in WT mice only. Exercise training of young mice increased...

  2. Gene program-specific regulation of PGC-1{alpha} activity

    DEFF Research Database (Denmark)

    Schmidt, Søren F; Mandrup, Susanne

    2011-01-01

    Peroxisome proliferator-activated receptor γ (PPARγ) coactivator 1 α (PGC-1α) activation coordinates induction of the hepatic fasting response through coactivation of numerous transcription factors and gene programs. In the June 15, 2011, issue of Genes & Development, Lustig and colleagues (pp....... 1232-1244) demonstrated that phosphorylation of PGC-1α by the p70 ribosomal protein S6 kinase 1 (S6K1) specifically interfered with the interaction between PGC-1α and HNF4α in liver and blocked the coactivation of the gluconeogenic target genes. This demonstrates how independent fine-tuning of gene...

  3. Hypothalamic PGC-1 alpha Protects Against High-Fat Diet Exposure by Regulating ER alpha

    NARCIS (Netherlands)

    Morselli, Eugenia; Fuente-Martin, Esther; Finan, Brian; Kim, Min; Frank, Aaron; Garcia-Caceres, Cristina; Navas, Carlos Rodriguez; Gordillo, Ruth; Neinast, Michael; Kalainayakan, Sarada P.; Li, Dan L.; Gao, Yuanqing; Yi, Chun-Xia; Hahner, Lisa; Palmer, Biff F.; Tschöp, Matthias H.; Clegg, Deborah J.

    2014-01-01

    High-fat diets (HFDs) lead to obesity and inflammation in the central nervous system (CNS). Estrogens and estrogen receptor alpha (ER alpha) protect premenopausal females from the metabolic complications of inflammation and obesity-related disease. Here, we demonstrate that hypothalamic PGC-1 alpha

  4. The contraction induced increase in gene expression of peroxisome proliferator-activated receptor (PPAR)-gamma coactivator 1alpha (PGC-1alpha), mitochondrial uncoupling protein 3 (UCP3) and hexokinase II (HKII) in primary rat skeletal muscle cells is dependent on reactive oxygen species

    DEFF Research Database (Denmark)

    Silveira, Leonardo R.; Pilegaard, Henriette; Kusuhara, Keiko

    2006-01-01

    We evaluated the role of reactive oxygen species (ROS) for the contraction induced increase in expression of PGC-1alpha, HKII and UCP3 mRNA. Rat skeletal muscle cells were subjected to acute or repeated electrostimulation in the presence and absence of antioxidants. Contraction of muscle cells lead...... to an increased H2O2 formation, as measured by oxidation of H2HFF. Acute contraction of the muscle cells lead to a transient increase in PGC-1alpha and UCP3 mRNA by 172 and 65%, respectively (pantioxidants. Repeated contraction sessions induced...... a sustained elevation in PGC-1alpha and UCP3 mRNA and a transient increase in HKII (pantioxidant cocktail or with GPX+GSH. Incubation of cells for 10 days with ROS produced by xanthine oxidase/xanthine increased the level of PGC-1...

  5. Relative workload determines exercise-induced increases in PGC-1alpha mRNA

    DEFF Research Database (Denmark)

    Nordsborg, Nikolai Baastrup; Lundby, Carsten; Leick, Lotte

    2010-01-01

    INTRODUCTION:: The hypothesis that brief intermittent exercise induced increases in human skeletal muscle metabolic mRNA is dependent on relative workload was investigated. METHODS:: Trained (n=10) and untrained (n=8) subjects performed exhaustive intermittent cycling exercise (4x4 min @ 85% of VO2...... peak, interspersed by 3 min). Trained subjects also performed the intermittent exercise at the same absolute workload as untrained, corresponding to 70% of VO2 peak (n=6). RESULTS:: Exercise at 85% of VO2 peak elevated (P... and untrained, respectively. PGC-1alpha mRNA expression was increased (Pelevated (3.1+/-0.7 mM) and PGC-1alpha mRNA content was less (P

  6. Non-CpG methylation of the PGC-1alpha promoter through DNMT3B controls mitochondrial density

    DEFF Research Database (Denmark)

    Barres, Romain; Osler, Megan E; Yan, Jie

    2009-01-01

    -CpG nucleotides. Non-CpG methylation was acutely increased in human myotubes by exposure to tumor necrosis factor-alpha (TNF-alpha) or free fatty acids, but not insulin or glucose. Selective silencing of the DNA methyltransferase 3B (DNMT3B), but not DNMT1 or DNMT3A, prevented palmitate-induced non......-CpG methylation of PGC-1alpha and decreased mtDNA and PGC-1alpha mRNA. We provide evidence for PGC-1alpha hypermethylation, concomitant with reduced mitochondrial content in type 2 diabetic patients, and link DNMT3B to the acute fatty-acid-induced non-CpG methylation of PGC-1alpha promoter....

  7. Fasting induces basolateral uptake transporters of the SLC family in the liver via HNF4alpha and PGC1alpha.

    Science.gov (United States)

    Dietrich, Christoph G; Martin, Ina V; Porn, Anne C; Voigt, Sebastian; Gartung, Carsten; Trautwein, Christian; Geier, Andreas

    2007-09-01

    Fasting induces numerous adaptive changes in metabolism by several central signaling pathways, the most important represented by the HNF4alpha/PGC-1alpha-pathway. Because HNF4alpha has been identified as central regulator of basolateral bile acid transporters and a previous study reports increased basolateral bile acid uptake into the liver during fasting, we hypothesized that HNF4alpha is involved in fasting-induced bile acid uptake via upregulation of basolateral bile acid transporters. In rats, mRNA of Ntcp, Oatp1, and Oatp2 were significantly increased after 48 h of fasting. Protein expression as determined by Western blot showed significant increases for all three transporters 72 h after the onset of fasting. Whereas binding activity of HNF1alpha in electrophoretic mobility shift assays remained unchanged, HNF4alpha binding activity to the Ntcp promoter was increased significantly. In line with this result, we found significantly increased mRNA expression of HNF4alpha and PGC-1alpha. Functional studies in HepG2 cells revealed an increased endogenous NTCP mRNA expression upon cotransfection with either HNF4alpha, PGC-1alpha, or a combination of both. We conclude that upregulation of the basolateral bile acid transporters Ntcp, Oatp1, and Oatp2 in fasted rats is mediated via the HNF4alpha/PGC-1alpha pathway.

  8. PGC-1alpha is required for training-induced prevention of age-associated decline in mitochondrial enzymes in mouse skeletal muscle

    DEFF Research Database (Denmark)

    Leick, Lotte; Lyngby, Stine Secher; Wojtaszewski, Jørgen

    2010-01-01

    The aim of the present study was to test the hypothesis that exercise training prevents an age-associated decline in skeletal muscle mitochondrial enzymes through a PGC-1alpha dependent mechanism. Whole body PGC-1alpha knock-out (KO) and littermate wildtype (WT) mice were submitted to long term...

  9. Effect of mild intermittent hypoxia on glucose tolerance, muscle morphology and AMPK-PGC-1alpha signaling.

    Science.gov (United States)

    Chen, Chung-Yu; Tsai, Ying-Lan; Kao, Chung-Lan; Lee, Shin-Da; Wu, Ming-Chieh; Mallikarjuna, K; Liao, Yi-Hung; Ivy, John L; Kuo, Chia-Hua

    2010-02-28

    The main goal of this study was to investigate the long-term effect of daily 8-hour mild intermittent hypoxia (14-15% O2) on glucose tolerance and muscle morphology of Sprague-Dawley rats. The involvement of AMPK-PGC-1alpha-VEGF signaling pathways in the skeletal muscle was also determined during the first 8 hours of hypoxia. We found that mRNA levels of VEGF and PGC-1alpha were significantly increased above control after 8-h mild hypoxia without a change in AMPK phosphorylation. After 8 weeks of mild intermittent hypoxia treatment, plasma glucose and insulin levels in oral glucose tolerance test (OGTT), epididymal fat mass, and body weight were significantly lower compared to the control group. While soleus muscle weight was not changed, capillary and fiber densities in the hypoxia group were 33% and 35% above the control suggesting reorganization of muscle fibers. In conclusion, our data provide strong evidence that long-term mild intermittent hypoxia decreases the diffusion distance of glucose and insulin across muscle fibers, and decreases adiposity in rats. These changes may account for the improved glucose tolerance observed following the 8-week hypoxia treatment, and provides grounds for investigating the development of a mild non-pharmacological intervention in the treatment of obesity and type 2 diabetes.

  10. Role of PGC-1{alpha} in exercise and fasting induced adaptations in mouse liver

    DEFF Research Database (Denmark)

    Haase, Tobias Nørresø; Jørgensen, Stine Ringholm; Leick, Lotte

    2011-01-01

    The transcriptional coactivator peroxisome proliferator activated receptor (PPAR)-¿ coactivator (PGC)-1a plays a role in regulation of several metabolic pathways. By use of whole body PGC-1a knockout (KO) mice we investigated the role of PGC-1a in fasting, acute exercise and exercise training ind...... role in regulation of Cyt c and COXI expression in the liver in response to a single exercise bout and prolonged exercise training, which implies that exercise training induced improvements in oxidative capacity of the liver is regulated by PGC-1a.......The transcriptional coactivator peroxisome proliferator activated receptor (PPAR)-¿ coactivator (PGC)-1a plays a role in regulation of several metabolic pathways. By use of whole body PGC-1a knockout (KO) mice we investigated the role of PGC-1a in fasting, acute exercise and exercise training...... induced regulation of key proteins in gluconeogenesis and metabolism in the liver. In both wild type (WT) and PGC-1a KO mice liver, the mRNA content of the gluconeogenic proteins glucose-6-phosphatase (G6Pase) and phosphoenolpyruvate carboxykinase (PEPCK) was upregulated during fasting. Pyruvate...

  11. PGC-1{alpha}, A Potential Therapeutic Target for Early Intervention in Parkinson's Disease

    DEFF Research Database (Denmark)

    Zheng, B.; Liao, Z.; Locascio, J.J.

    2010-01-01

    with symptomatic Parkinson's and subclinical disease and healthy controls. We analyzed 6.8 million raw data points from nine genome-wide expression studies, and 185 laser-captured human dopaminergic neuron and substantia nigra transcriptomes, followed by two-stage replication on three platforms. We found 10 gene...... sets with previously unknown associations with Parkinson's disease. These gene sets pinpoint defects in mitochondrial electron transport, glucose utilization, and glucose sensing and reveal that they occur early in disease pathogenesis. Genes controlling cellular bioenergetics that are expressed...... in response to peroxisome proliferator-activated receptor γ coactivator-1α (PGC-1α) are underexpressed in Parkinson's disease patients. Activation of PGC-1α results in increased expression of nuclear-encoded subunits of the mitochondrial respiratory chain and blocks the dopaminergic neuron loss induced...

  12. Mitochondrial Effects of PGC-1alpha Silencing in MPP+ Treated Human SH-SY5Y Neuroblastoma Cells

    Directory of Open Access Journals (Sweden)

    Qinyong Ye

    2017-05-01

    Full Text Available The dopaminergic neuron degeneration and loss that occurs in Parkinson’s disease (PD has been tightly linked to mitochondrial dysfunction. Although the aged-related cause of the mitochondrial defect observed in PD patients remains unclear, nuclear genes are of potential importance to mitochondrial function. Human peroxisome proliferator-activated receptor γ coactivator-1alpha (PGC-1α is a multi-functional transcription factor that tightly regulates mitochondrial biogenesis and oxidative capacity. The goal of the present study was to explore the potential pathogenic effects of interference by the PGC-1α gene on N-methyl-4-phenylpyridinium ion (MPP+-induced SH-SY5Y cells. We utilized RNA interference (RNAi technology to probe the pathogenic consequences of inhibiting PGC-1α in the SH-SY5Y cell line. Remarkably, a reduction in PGC-1α resulted in the reduction of mitochondrial membrane potential, intracellular ATP content and intracellular H2O2 generation, leading to the translocation of cytochrome c (cyt c to the cytoplasm in the MPP+-induced PD cell model. The expression of related proteins in the signaling pathway (e.g., estrogen-related receptor α (ERRα, nuclear respiratory factor 1 (NRF-1, NRF-2 and Peroxisome proliferator-activated receptor γ (PPARγ also decreased. Our finding indicates that small interfering RNA (siRNA interference targeting the PGC-1α gene could inhibit the function of mitochondria in several capacities and that the PGC-1α gene may modulate mitochondrial function by regulating the expression of ERRα, NRF-1, NRF-2 and PPARγ. Thus, PGC-1α can be considered a potential therapeutic target for PD.

  13. Mitochondrial-related gene expression profiles suggest an important role of PGC-1alpha in the compensatory mechanism of endemic dilated cardiomyopathy

    Energy Technology Data Exchange (ETDEWEB)

    He, Shu-Lan [Key Laboratory of Environment and Gene Related Diseases, Xi' an Jiaotong University, Ministry Education, No. 76 Yanta West Road, Xi' an, Shaanxi 710061 (China); Key Laboratory of Trace Elements and Endemic Diseases, Xi' an Jiaotong University, Ministry of Health, No. 76 Yanta West Road, Xi' an, Shaanxi 710061 (China); Tan, Wu-Hong, E-mail: tanwh@mail.xjtu.edu.cn [Key Laboratory of Environment and Gene Related Diseases, Xi' an Jiaotong University, Ministry Education, No. 76 Yanta West Road, Xi' an, Shaanxi 710061 (China); Key Laboratory of Trace Elements and Endemic Diseases, Xi' an Jiaotong University, Ministry of Health, No. 76 Yanta West Road, Xi' an, Shaanxi 710061 (China); Zhang, Zeng-Tie; Zhang, Feng [Key Laboratory of Environment and Gene Related Diseases, Xi' an Jiaotong University, Ministry Education, No. 76 Yanta West Road, Xi' an, Shaanxi 710061 (China); Key Laboratory of Trace Elements and Endemic Diseases, Xi' an Jiaotong University, Ministry of Health, No. 76 Yanta West Road, Xi' an, Shaanxi 710061 (China); Qu, Cheng-Juan [Institute of Biomedicine, University of Eastern Finland, Kuopio (Finland); Lei, Yan-Xia; Zhu, Yan-He [Key Laboratory of Environment and Gene Related Diseases, Xi' an Jiaotong University, Ministry Education, No. 76 Yanta West Road, Xi' an, Shaanxi 710061 (China); Key Laboratory of Trace Elements and Endemic Diseases, Xi' an Jiaotong University, Ministry of Health, No. 76 Yanta West Road, Xi' an, Shaanxi 710061 (China); Yu, Han-Jie [Department of Biotechnology, Northwest University, Xi' an, Shaanxi 710069 (China); Xiang, You-Zhang [Shandong Institute for prevention and Treatment of Endemic Disease, Jinan, Shandong 250014 (China); and others

    2013-10-15

    Keshan disease (KD) is an endemic dilated cardiomyopathy with unclear etiology. In this study, we compared mitochondrial-related gene expression profiles of peripheral blood mononuclear cells (PBMCs) derived from 16 KD patients and 16 normal controls in KD areas. Total RNA was isolated, amplified, labeled and hybridized to Agilent human 4×44k whole genome microarrays. Mitochondrial-related genes were screened out by the Third-Generation Human Mitochondria-Focused cDNA Microarray (hMitChip3). Quantitative real-time PCR, immunohistochemical and biochemical parameters related mitochondrial metabolism were conducted to validate our microarray results. In KD samples, 34 up-regulated genes (ratios≥2.0) were detected by significance analysis of microarrays and ingenuity systems pathway analysis (IPA). The highest ranked molecular and cellular functions of the differentially regulated genes were closely related to amino acid metabolism, free radical scavenging, carbohydrate metabolism, and energy production. Using IPA, 40 significant pathways and four significant networks, involved mainly in apoptosis, mitochondrion dysfunction, and nuclear receptor signaling were identified. Based on our results, we suggest that PGC-1alpha regulated energy metabolism and anti-apoptosis might play an important role in the compensatory mechanism of KD. Our results may lead to the identification of potential diagnostic biomarkers for KD in PBMCs, and may help to understand the pathogenesis of KD. Highlights: • Thirty-four up-regulated genes were detected in KD versus health controls. • Forty pathways and four networks were detected in KD. • PGC-1alpha regulated energy metabolism and anti-apoptosis in KD.

  14. Maintenance of Glucose Homeostasis Through Acetylation of the Metabolic Transcriptional Coactivator PGC1-alpha

    Science.gov (United States)

    2011-02-01

    Salmenniemi, U., Ruotsalainen, E., Pihlajamaki, J., Vauhkonen, I., Kai - nulainen, S., Punnonen, K., Vanninen, E., and Laakso, M. (2004). Mul- tiple...cancer: a dawn for evolutionary medicine. Annu. Rev. Genet. 39, 359–407. Wang, Y.X., Zhang, C.L., Yu , R.T., Cho, H.K., Nelson, M.C., Bayuga- Ocampo...calorie diet, Nature 444 (2006) 337–342. [19] J.M. Wu, Z.R. Wang, T.C. Hsieh , J.L. Bruder, J.G. Zou, Y.Z. Huang, Mechanism of cardioprotection by

  15. Evidence of an association between genetic variation of the coactivator PGC-1beta and obesity

    DEFF Research Database (Denmark)

    Andersen, G; Wegner, L; Yanagisawa, K

    2005-01-01

    Peroxisome proliferator activated receptor-gamma coactivator-1beta (PGC-1beta) is a recently identified homologue of the tissue specific coactivator PGC-1alpha, a coactivator of transcription factors such as the peroxisome proliferators activated receptors and nuclear respiratory factors. PGC-1...

  16. PGC-1alpha in exercise- and exercise training-induced metabolic adaptations

    DEFF Research Database (Denmark)

    Jørgensen, Stine Ringholm

    and interferes with the exercise-induced adaptive response in human skeletal muscle. Study II demonstrates that mouse liver glucose-6-phosphatase (G6Pase) mRNA content increased in recovery from acute exercise in both wildtype (WT) and PGC-1α knockout (KO) mice, while phosphoenolpyruvate carboxykinase (PEPCK......) and pyruvate carboxylase mRNA content did not change in either genotype. Exercise training increased PEPCK protein content in both WT and PGC-1α KO mice. In addition, the mRNA and protein content of cytochrome (Cyt) c and cytochrome c oxidase (COX) subunit I increased in response to acute exercise and exercise...

  17. ADD1/SREBP1c activates the PGC1-alpha promoter in brown adipocytes

    DEFF Research Database (Denmark)

    Hao, Qin; Hansen, Jacob B; Petersen, Rasmus K

    2010-01-01

    Cold adaptation elicits a paradoxical simultaneous induction of fatty acid synthesis and beta-oxidation in brown adipose tissue. We show here that cold exposure coordinately induced liver X receptor alpha (LXRalpha), adipocyte determination and differentiation-dependent factor 1 (ADD1)/sterol...

  18. Effects of Wnt signaling on brown adipocyte differentiation and metabolism mediated by PGC-1alpha

    DEFF Research Database (Denmark)

    Kang, Sona; Bajnok, Laszlo; Longo, Kenneth A

    2005-01-01

    Activation of canonical Wnt signaling inhibits brown adipogenesis of cultured cells by impeding induction of PPARgamma and C/EBPalpha. Although enforced expression of these adipogenic transcription factors restores lipid accumulation and expression of FABP4 in Wnt-expressing cells, additional...

  19. PPARgamma-PGC-1alpha activity is determinant of alcohol related breast cancer

    DEFF Research Database (Denmark)

    Koefoed Petersen, Rasmus; Benzon Larsen, Signe; Jensen, Ditte Marie

    2012-01-01

    Alcohol is a risk factor for postmenopausal breast cancer. One of several proposed mechanisms is that alcohol-related breast cancer is caused by increased sex hormone levels. PPARγ inhibits aromatase transcription in breast adipocytes. We reproduced previously found allele-specific effects...... of the wildtype Pro-allele of PPARG Pro12Ala in alcohol related breast cancer. In transiently transfected cells, transcriptional activation by PPARγ and the PPARγ-PGC-1α complex was inhibited by ethanol. PPARγ 12Ala-mediated transcription activation was not enhanced by PGC-1α, resulting in allele......-specific transcription activation by the PPARγ 12Pro-PGC-1α complex. Our results suggest that PPARγ and PGC-1α activity is an important determinant of alcohol related breast cancer....

  20. Peroxisome proliferator-activated receptor gamma coactivator-1 alpha acts as a tumor suppressor in hepatocellular carcinoma.

    Science.gov (United States)

    Liu, Rui; Zhang, Haiyang; Zhang, Yan; Li, Shuang; Wang, Xinyi; Wang, Xia; Wang, Cheng; Liu, Bin; Zen, Ke; Zhang, Chen-Yu; Zhang, Chunni; Ba, Yi

    2017-04-01

    Peroxisome proliferator-activated receptor gamma coactivator-1 alpha plays a crucial role in regulating the biosynthesis of mitochondria, which is closely linked to the energy metabolism in various tumors. This study investigated the regulatory role of peroxisome proliferator-activated receptor gamma coactivator-1 alpha in the pathogenesis of hepatocellular carcinoma. In this study, the changes of peroxisome proliferator-activated receptor gamma coactivator-1 alpha messenger RNA levels between normal human liver and hepatocellular carcinoma tissue were examined by quantitative reverse transcription polymerase chain reaction. Knockdown of peroxisome proliferator-activated receptor gamma coactivator-1 alpha was conducted by RNA interference in the human liver cell line L02, while overexpression of peroxisome proliferator-activated receptor gamma coactivator-1 alpha was conducted by adenovirus encoding peroxisome proliferator-activated receptor gamma coactivator-1 alpha complementary DNA in the human hepatocarcinoma cell line HepG2. Cellular morphological changes were observed via optical and electron microscopy. Cellular apoptosis was determined by Hoechst 33258 staining. In addition, the expression levels of 21,400 genes in tissues and cells were detected by microarray. It was shown that peroxisome proliferator-activated receptor gamma coactivator-1 alpha expression was significantly downregulated in hepatocellular carcinoma compared with normal liver tissues. After knockdown of peroxisome proliferator-activated receptor gamma coactivator-1 alpha expression in L02 cells, cells reverted to immature and dedifferentiated morphology exhibiting cancerous tendency. Apoptosis occurred in the HepG2 cells after transfection by adenovirus encoding peroxisome proliferator-activated receptor gamma coactivator-1 alpha. Microarray analysis showed consistent results. The results suggest that peroxisome proliferator-activated receptor gamma coactivator-1 alpha acts as a tumor

  1. Multi-regulatory network of ROS: the interconnection of ROS, PGC-1 alpha, and AMPK-SIRT1 during exercise.

    Science.gov (United States)

    Thirupathi, Anand; de Souza, Claudio Teodoro

    2017-11-01

    Transcriptional factors are easily susceptible to any stimuli, including exercise. Exercise can significantly influence PGC-1 α and AMPK-SIRT1 pathway, as it is involved in the regulation of energy metabolism and mitochondrial biogenesis. Exercise is a major energy deprivation process by which many of transcription factors get tuned positively. However, how transcription factors help to boost the antioxidant defense system at cellular level is elusive. It is well known that physical exercise can induce reactive oxygen species, but how these reactive oxygen species can help to regulate multiple transcription factors during exercise is an important area to be discussed yet. This review mainly focuses on interconnecting role of PGC-1 α and AMPK-SIRT1 pathway during exercise and how these proteins are getting tuned by reactive oxygen species in exercise condition.

  2. Rev1 contributes to proper mitochondrial function via the PARP-NAD(+)-SIRT1-PGC1 alpha axis

    DEFF Research Database (Denmark)

    Fakouri, Nima Borhan; Durhuus, Jon Ambaek; Regnell, Christine Elisabeth

    2017-01-01

    (ADP) ribose polymerase 1 (PARP1) activity, low endogenous NAD+, low expression of SIRT1 and PGC1α and low adenosine monophosphate (AMP)-activated kinase (AMPK) activity. We conclude that replication stress via Rev1-deficiency contributes to metabolic stress caused by compromized mitochondrial function via...... the PARP-NAD+-SIRT1-PGC1α axis....

  3. Efecto del entrenamiento físico sobre la mitocondriogénesis y la expresión de enzimas antioxidantes en el músculo de animales jóvenes, viejos y knockout de PGC-1 ALPHA

    OpenAIRE

    Nascimento, Ana Lucia

    2010-01-01

    El envejecimiento humano está asociado a una pérdida de masa muscular que se inicia en la cuarta década de la vida con una pérdida de fuerza de un 1% al año y que se acelera con el transcurso de los años. Las causas del envejecimiento del organismo son complejas. Una amplia variedad de procesos se considera que están implicados en el declive de los distintos aparatos y sistemas con el paso de los años. Dentro los factores implicados en la pérdida de la funcionalidad del músc...

  4. Peroxisome proliferator activator receptor gamma coactivator-1alpha (PGC-1α improves motor performance and survival in a mouse model of amyotrophic lateral sclerosis

    Directory of Open Access Journals (Sweden)

    Cheng Alice

    2011-07-01

    Full Text Available Abstract Background Amyotrophic lateral sclerosis (ALS is a devastating neurodegenerative disease that affects spinal cord and cortical motor neurons. An increasing amount of evidence suggests that mitochondrial dysfunction contributes to motor neuron death in ALS. Peroxisome proliferator-activated receptor gamma co-activator-1α (PGC-1α is a principal regulator of mitochondrial biogenesis and oxidative metabolism. Results In this study, we examined whether PGC-1α plays a protective role in ALS by using a double transgenic mouse model where PGC-1α is over-expressed in an SOD1 transgenic mouse (TgSOD1-G93A/PGC-1α. Our results indicate that PGC-1α significantly improves motor function and survival of SOD1-G93A mice. The behavioral improvements were accompanied by reduced blood glucose level and by protection of motor neuron loss, restoration of mitochondrial electron transport chain activities and inhibition of stress signaling in the spinal cord. Conclusion Our results demonstrate that PGC-1α plays a beneficial role in a mouse model of ALS, suggesting that PGC-1α may be a potential therapeutic target for ALS therapy.

  5. Hepatic oxidative stress in ovariectomized transgenic mice expressing the hepatitis C virus polyprotein is augmented through suppression of adenosine monophosphate-activated protein kinase/proliferator-activated receptor gamma co-activator 1 alpha signaling.

    Science.gov (United States)

    Tomiyama, Yasuyuki; Nishina, Sohji; Hara, Yuichi; Kawase, Tomoya; Hino, Keisuke

    2014-10-01

    Oxidative stress plays an important role in hepatocarcinogenesis of hepatitis C virus (HCV)-related chronic liver diseases. Despite the evidence of an increased proportion of females among elderly patients with HCV-related hepatocellular carcinoma (HCC), it remains unknown whether HCV augments hepatic oxidative stress in postmenopausal women. The aim of this study was to determine whether oxidative stress was augmented in ovariectomized (OVX) transgenic mice expressing the HCV polyprotein and to investigate its underlying mechanisms. OVX and sham-operated female transgenic mice expressing the HCV polyprotein and non-transgenic littermates were assessed for the production of reactive oxygen species (ROS), expression of inflammatory cytokines and antioxidant potential in the liver. Compared with OVX non-transgenic mice, OVX transgenic mice showed marked hepatic steatosis and ROS production without increased induction of inflammatory cytokines, but there was no increase in ROS-detoxifying enzymes such as superoxide dismutase 2 and glutathione peroxidase 1. In accordance with these results, OVX transgenic mice showed less activation of peroxisome proliferator-activated receptor-γ co-activator-1α (PGC-1α), which is required for the induction of ROS-detoxifying enzymes, and no activation of adenosine monophosphate-activated protein kinase-α (AMPKα), which regulates the activity of PGC-1α. Our study demonstrated that hepatic oxidative stress was augmented in OVX transgenic mice expressing the HCV polyprotein by attenuation of antioxidant potential through inhibition of AMPK/PGC-1α signaling. These results may account in part for the mechanisms by which HCV-infected women are at high risk for HCC development when some period has passed after menopause. © 2013 The Japan Society of Hepatology.

  6. PGC-1beta is downregulated by training in human skeletal muscle: no effect of training twice every second day vs. once daily on expression of the PGC-1 family

    DEFF Research Database (Denmark)

    Mortensen, Ole Hartvig; Plomgaard, Peter; Fischer, Christian P

    2007-01-01

    We hypothesized that the peroxisome proliferator-activated receptor-gamma coactivator-1 (PGC-1) family of transcriptional coactivators (PGC-1alpha, PGC-1beta, and PRC) is differentially regulated by training once daily vs. training twice daily every second day and that this difference might...... be observed in the acute response to endurance exercise. Furthermore, we hypothesized that expression levels of the PGC-1 family differ with muscular fiber-type composition. Thus, before and after 10 wk of knee extensor endurance training, training one leg once daily and the other leg twice daily every second...... day, keeping the total amount of training for the legs equal, skeletal muscle mRNA expression levels of PGC-1alpha, PGC-1beta, and PRC were determined in young healthy men (n = 7) in response to 3 h of acute exercise. No significant difference was found between the two legs, suggesting that regulation...

  7. New Advances in Molecular Therapy for Muscle Repair after Diseases and Injuries

    Science.gov (United States)

    2008-04-01

    PT, Zhang, CY, Wu, Z, Boss, O et al. (2002). Transcriptional co-activator PGC-1 alpha drives the formation of slow - twitch muscle fibres . Nature...Calcineurin and CaMK signaling pathways in fast -to- slow fiber type transformation of cultured mouse skeletal muscle fibers Xiaodong Mu, PhD The John...Surgery”). 3. Ectopic bone formation in fast and slow skeletal muscle (Meszaros L., “Influence of vascularity on muscle regeneration, fibrosis and

  8. PGC-1α-mediated adaptations in skeletal muscle

    DEFF Research Database (Denmark)

    Olesen, Jesper; Kiilerich, Kristian; Pilegaard, Henriette

    2010-01-01

    multiple pathways and functions underline the potential importance of PGC-1alpha in skeletal muscle adaptations in humans. The absence of exercise-induced PGC-1alpha-mediated gene regulation during a physical inactive lifestyle is suggested to lead to reduced oxidative capacity of skeletal muscle...... involved in angiogenesis and the anti-oxidant defence as well as to affect expression of inflammatory markers. Exercise increases PGC-1alpha transcription and potentially PGC-1alpha activity through post-translational modifications, and concomitant PGC-1alpha-mediated gene regulation is suggested...... to be an underlying mechanism for adaptations in skeletal muscle, when exercise is repeated. The current review presents some of the key findings in PGC-1alpha-mediated regulation of metabolically related, anti-oxidant and inflammatory proteins in skeletal muscle in the basal state and in response to exercise...

  9. 6-Mercaptopurine, an activator of Nur77, enhances transcriptional activity of HIF-1alpha resulting in new vessel formation.

    Science.gov (United States)

    Yoo, Y-G; Na, T-Y; Yang, W-K; Kim, H-J; Lee, I-K; Kong, G; Chung, J-H; Lee, M-O

    2007-05-31

    Hypoxia-inducible factor-1alpha (HIF-1alpha) plays a central role in oxygen homeostasis. Previously, we reported that the orphan nuclear receptor Nur77 functions in stabilizing HIF-1alpha. Here, we demonstrate that 6-mercaptopurine (6-MP), an activator of the NR4A family members, enhances transcriptional activity of HIF-1. 6-MP enhanced the protein-level of HIF-1alpha as well as vascular endothelial growth factor (VEGF) in a dose- and time-dependent manner. The induction of HIF-1alpha was abolished by the transfection of either a dominant-negative Nur77 mutant or si-Nur77, indicating a critical role of Nur77 in the 6-MP action. The HIF-1alpha protein level remained up to 60 min in the presence of 6-MP when de novo protein synthesis was blocked by cycloheximide, suggesting that 6-MP induces stabilization of the HIF-1alpha protein. The fact that 6-MP decreased the association of HIF-1alpha with von Hippel-Lindau protein and the acetylation of HIF-1alpha, may explain how 6-MP induced stability of HIF-1alpha. Further, 6-MP induced the transactivation function of HIF-1alpha by recruiting co-activator cyclic-AMP-response-element-binding protein. Finally, 6-MP enhanced the expression of HIF-1alpha and VEGF, and the formation of capillary tubes in human umbilical vascular endothelial cells. Together, our results provide a new insight for 6-MP action in the stabilization of HIF-1alpha and imply a potential application of 6-MP in hypoxia-associated human vascular diseases.

  10. LKB1-AMPK signaling in muscle from obese insulin-resistant Zucker rats and effects of training.

    Science.gov (United States)

    Sriwijitkamol, Apiradee; Ivy, John L; Christ-Roberts, Christine; DeFronzo, Ralph A; Mandarino, Lawrence J; Musi, Nicolas

    2006-05-01

    AMPK is a key regulator of fat and carbohydrate metabolism. It has been postulated that defects in AMPK signaling could be responsible for some of the metabolic abnormalities of type 2 diabetes. In this study, we examined whether insulin-resistant obese Zucker rats have abnormalities in the AMPK pathway. We compared AMPK and ACC phosphorylation and the protein content of the upstream AMPK kinase LKB1 and the AMPK-regulated transcriptional coactivator PPARgamma coactivator-1 (PGC-1) in gastrocnemius of sedentary obese Zucker rats and sedentary lean Zucker rats. We also examined whether 7 wk of exercise training on a treadmill reversed abnormalities in the AMPK pathway in obese Zucker rats. In the obese rats, AMPK phosphorylation was reduced by 45% compared with lean rats. Protein expression of the AMPK kinase LKB1 was also reduced in the muscle from obese rats by 43%. In obese rats, phosphorylation of ACC and protein expression of PGC-1alpha, two AMPK-regulated proteins, tended to be reduced by 50 (P = 0.07) and 35% (P = 0.1), respectively. There were no differences in AMPKalpha1, -alpha2, -beta1, -beta2, and -gamma3 protein content between lean and obese rats. Training caused a 1.5-fold increase in AMPKalpha1 protein content in the obese rats, although there was no effect of training on AMPK phosphorylation and the other AMPK isoforms. Furthermore, training also significantly increased LKB1 and PGC-1alpha protein content 2.8- and 2.5-fold, respectively, in the obese rats. LKB1 protein strongly correlated with hexokinase II activity (r = 0.75, P = 0.001), citrate synthase activity (r = 0.54, P = 0.02), and PGC-1alpha protein content (r = 0.81, P < 0.001). In summary, obese insulin-resistant rodents have abnormalities in the LKB1-AMPK-PGC-1 pathway in muscle, and these abnormalities can be restored by training.

  11. Cytokine vaccination: neutralising IL-1alpha autoantibodies induced by immunisation with homologous IL-1alpha

    DEFF Research Database (Denmark)

    Svenson, M; Hansen, M B; Thomsen, Allan Randrup

    2000-01-01

    with IL-1alpha coupled to purified protein derivative of tuberculin (PPD). Both unprimed and primed animals developed IgG aAb to IL-1alpha. These aAb persisted at high levels more than 100 days after vaccination and did not cross-react with murine IL-1beta. The induced anti-IL-1alpha aAb inhibited binding...... in mice by vaccination with recombinant murine IL-1alpha conjugated to PPD. Studies of the effects of IL-1alpha aAb in such animals may help clarify the importance of naturally occurring IL-1alpha aAb in humans and permit the evaluation of future therapies with cytokine aAb in patients...

  12. DP97, a DEAD box DNA/RNA helicase, is a target gene-selective co-regulator of the constitutive androstane receptor

    Energy Technology Data Exchange (ETDEWEB)

    Kanno, Yuichiro, E-mail: ykanno@phar.toho-u.ac.jp [Faculty of Pharmaceutical Sciences, Toho University, Chiba (Japan); Serikawa, Takafumi; Inajima, Jun; Inouye, Yoshio [Faculty of Pharmaceutical Sciences, Toho University, Chiba (Japan)

    2012-09-14

    Highlights: Black-Right-Pointing-Pointer DP97 interacts with nuclear receptor CAR. Black-Right-Pointing-Pointer DP97 enhances CAR-mediated transcriptional activation. Black-Right-Pointing-Pointer DP97 synergistically enhances transactivity of CAR by the co-expression of SRC-1 or PGC1{alpha}. Black-Right-Pointing-Pointer DP97 is a gene-selective co-activator for hCAR. -- Abstract: The constitutive androstane receptor (CAR) plays a key role in the expression of xenobiotic/steroid and drug metabolizing enzymes and their transporters. In this study, we demonstrated that DP97, a member of the DEAD box DNA/RNA helicase protein family, is a novel CAR-interacting protein. Using HepG2 cells expressing human CAR in the presence of tetracycline, we showed that knockdown of DP97 with small interfering RNAs suppressed tetracycline-inducible mRNA expression of CYP2B6 and UGT1A1 but not CYP3A4. Thus, DP97 was found to be a gene (or promoter)-selective co-activator for hCAR. DP97-mediated CAR transactivation was synergistically enhanced by the co-expression of SRC-1 or PGC1{alpha}, therefore it might act as mediator between hCAR and appropriate co-activators.

  13. Anti-IL-1alpha autoantibodies in early rheumatoid arthritis

    DEFF Research Database (Denmark)

    Forslind, K; Svensson, Birte; Svenson, M

    2001-01-01

    To investigate the potential predictive value of autoantibodies against IL1-alpha (anti-IL-1alpha) in patients with early rheumatoid arthritis (RA).......To investigate the potential predictive value of autoantibodies against IL1-alpha (anti-IL-1alpha) in patients with early rheumatoid arthritis (RA)....

  14. Role of macrophage inflammatory protein-1 alpha (MIP-1 alpha) in acute lung injury in rats

    DEFF Research Database (Denmark)

    Shanley, T P; Schmal, H; Friedl, H P

    1995-01-01

    in bronchoalveolar lavage (BAL) fluids by Western blot analysis. Anti-MIP-1 alpha administered at commencement of IgG immune complex- or LPS-induced injury resulted in significant reductions in BAL neutrophils as well as in injury as measured by pulmonary vascular permeability. Under such conditions, in both models...... to production of TNF-alpha, which in turn up-regulates vascular adhesion molecules required for neutrophil influx....

  15. [Coactivators in energy metabolism: peroxisome proliferator-activated receptor-gamma coactivator 1 family].

    Science.gov (United States)

    Wang, Rui; Chang, Yong-sheng; Fang, Fu-de

    2009-12-01

    Peroxisome proliferator-activated receptor gamma coactivator 1 (PGC1) family is highly expressed in tissues with high energy metabolism. They coactivate transcription factors in regulating genes engaged in processes such as gluconeogenesis, adipose beta-oxydation, lipoprotein synthesis and secretion, mitochondrial biogenesis, and oxidative metabolism. Protein conformation studies demonstrated that they lack DNA binding domains and act as coactivators through physical interaction with transcription factors. PGC1 activity is regulated at transcription level or by multiple covalent chemical modifications such as phosphorylation, methylation and acetylation/deacetylation. Abnormal expression of PGC1 coactivators usually is closely correlated with diseases such as diabetes, obesity, hyperglycemia, hyperlipemia, and arterial and brain neuron necrosis diseases.

  16. Protein arginine methyltransferase 5 (PRMT5) is a novel coactivator of constitutive androstane receptor (CAR)

    International Nuclear Information System (INIS)

    Kanno, Yuichiro; Inajima, Jun; Kato, Sayaka; Matsumoto, Maika; Tokumoto, Chikako; Kure, Yuki; Inouye, Yoshio

    2015-01-01

    The constitutive androstane receptor (CAR) plays a key role in the expression of xenobiotic/steroid and drug metabolizing enzymes and their transporters. In this study, we demonstrated that protein arginine methyltransferase 5 (PRMT5) is a novel CAR-interacting protein. Furthermore, the PRMT-dependent induction of a CAR reporter gene, which was independent of methyltransferase activity, was enhanced in the presence of steroid receptor coactivator 1 (SRC1), peroxisome proliferator-activated receptor-gamma coactivator 1 alpha (PGC-1α) or DEAD box DNA/RNA helicase DP97. Using tetracycline inducible-hCAR system in HepG2 cells, we showed that knockdown of PRMT5 with small interfering RNA suppressed tetracycline -induced mRNA expression of CYP2B6 but not of CYP2C9 or CYP3A4. PRMT5 enhanced phenobarbital-mediated transactivation of a phenobarbital-responsive enhancer module (PBREM)-driven reporter gene in co-operation with PGC-1α in rat primary hepatocytes. Based on these findings, we suggest PRMT5 to be a gene (or promoter)-selective coactivator of CAR by mediating the formation of complexes between hCAR and appropriate coactivators. - Highlights: • Nuclear receptor CAR interact with PRMT5. • PRMT5 enhances transcriptional activity of CAR. • PRMT5 synergistically enhances transactivity of CAR by the co-expression of SRC-1, DP97 or PGC1α. • PRMT5 is a gene-selective co-activator for hCAR

  17. Protein arginine methyltransferase 5 (PRMT5) is a novel coactivator of constitutive androstane receptor (CAR)

    Energy Technology Data Exchange (ETDEWEB)

    Kanno, Yuichiro, E-mail: ykanno@phar.toho-u.ac.jp; Inajima, Jun; Kato, Sayaka; Matsumoto, Maika; Tokumoto, Chikako; Kure, Yuki; Inouye, Yoshio

    2015-03-27

    The constitutive androstane receptor (CAR) plays a key role in the expression of xenobiotic/steroid and drug metabolizing enzymes and their transporters. In this study, we demonstrated that protein arginine methyltransferase 5 (PRMT5) is a novel CAR-interacting protein. Furthermore, the PRMT-dependent induction of a CAR reporter gene, which was independent of methyltransferase activity, was enhanced in the presence of steroid receptor coactivator 1 (SRC1), peroxisome proliferator-activated receptor-gamma coactivator 1 alpha (PGC-1α) or DEAD box DNA/RNA helicase DP97. Using tetracycline inducible-hCAR system in HepG2 cells, we showed that knockdown of PRMT5 with small interfering RNA suppressed tetracycline -induced mRNA expression of CYP2B6 but not of CYP2C9 or CYP3A4. PRMT5 enhanced phenobarbital-mediated transactivation of a phenobarbital-responsive enhancer module (PBREM)-driven reporter gene in co-operation with PGC-1α in rat primary hepatocytes. Based on these findings, we suggest PRMT5 to be a gene (or promoter)-selective coactivator of CAR by mediating the formation of complexes between hCAR and appropriate coactivators. - Highlights: • Nuclear receptor CAR interact with PRMT5. • PRMT5 enhances transcriptional activity of CAR. • PRMT5 synergistically enhances transactivity of CAR by the co-expression of SRC-1, DP97 or PGC1α. • PRMT5 is a gene-selective co-activator for hCAR.

  18. Quercetin suppresses hypoxia-induced accumulation of hypoxia-inducible factor-1alpha (HIF-1alpha) through inhibiting protein synthesis.

    Science.gov (United States)

    Lee, Dae-Hee; Lee, Yong J

    2008-10-01

    Quercetin, a ubiquitous bioactive plant flavonoid, has been shown to inhibit the proliferation of cancer cells and induce the accumulation of hypoxia-inducible factor-1alpha (HIF-1alpha) in normoxia. In this study, under hypoxic conditions (1% O(2)), we examined the effect of quercetin on the intracellular level of HIF-1alpha and extracellular level of vascular endothelial growth factor (VEGF) in a variety of human cancer cell lines. Surprisingly, we observed that quercetin suppressed the HIF-1alpha accumulation during hypoxia in human prostate cancer LNCaP, colon cancer CX-1, and breast cancer SkBr3 cells. Quercetin treatment also significantly reduced hypoxia-induced secretion of VEGF. Suppression of HIF-1alpha accumulation during treatment with quercetin in hypoxia was not prevented by treatment with 26S proteasome inhibitor MG132 or PI3K inhibitor LY294002. Interestingly, hypoxia (1% O(2)) in the presence of 100 microM quercetin inhibited protein synthesis by 94% during incubation for 8 h. Significant quercetin concentration-dependent inhibition of protein synthesis and suppression of HIF-1alpha accumulation were observed under hypoxic conditions. Treatment with 100 microM cycloheximide, a protein synthesis inhibitor, replicated the effect of quercetin by inhibiting HIF-1alpha accumulation during hypoxia. These results suggest that suppression of HIF-1alpha accumulation during treatment with quercetin under hypoxic conditions is due to inhibition of protein synthesis. (c) 2008 Wiley-Liss, Inc.

  19. Small molecule PGC-1α1 protein stabilizers induce adipocyte Ucp1 expression and uncoupled mitochondrial respiration

    Directory of Open Access Journals (Sweden)

    A.T. Pettersson-Klein

    2018-03-01

    Full Text Available Objective: The peroxisome proliferator-activated receptor-γ coactivator-1α1 (PGC-1α1 regulates genes involved in energy metabolism. Increasing adipose tissue energy expenditure through PGC-1α1 activation is potentially beneficial for systemic metabolism. Pharmacological PGC-1α1 activators could be valuable tools in the fight against obesity and metabolic disease. Finding such compounds has been challenging partly because PGC-1α1 is a transcriptional coactivator with no known ligand-binding properties. While, PGC-1α1 activation is regulated by several mechanisms, protein stabilization is a crucial limiting step due to its short half-life under unstimulated conditions. Methods: We designed a cell-based high-throughput screening system to identify PGC-1α1 protein stabilizers. Positive hits were tested for their ability to induce endogenous PGC-1α1 protein accumulation and activate target gene expression in brown adipocytes. Select compounds were analyzed for their effects on global gene expression and cellular respiration in adipocytes. Results: Among 7,040 compounds screened, we highlight four small molecules with high activity as measured by: PGC-1α1 protein accumulation, target gene expression, and uncoupled mitochondrial respiration in brown adipocytes. Conclusions: We identify compounds that induce PGC-1α1 protein accumulation and show that this increases uncoupled respiration in brown adipocytes. This screening platform establishes the foundation for a new class of therapeutics with potential use in obesity and associated disorders. Keywords: Small molecule screening, PGC-1a, PGC-1alpha, PGC-1alpha1, Protein stabilization, UCP1, Mitochondrial respiration, Brown adipose tissue

  20. Stromal cell-derived factor-1 alpha (SDF-1 alpha) improves neural recovery after spinal cord contusion in rats

    NARCIS (Netherlands)

    Zendedel, A.; Nobakht, M.; Bakhtiyari, M.; Beyer, C.; Kipp, M.; Baazm, M.; Joghataie, M.T.

    2012-01-01

    Stromal cell-derived factor-1 alpha (SDF-1α) is an important cytokine, implicated in the control of stem cell trafficking and bone marrow-derived stem cell mobilization. Generally, SDF-1α regulates multiple physiological processes such as embryonic development and organ homeostasis. There is also

  1. High frequency of HIF-1 alpha overexpression in BRCA1 related breast cancer

    NARCIS (Netherlands)

    van der Groep, Petra; Bouter, Alwin; Menko, Fred H.; van der Wall, Elsken; van Diest, Paul J.

    2008-01-01

    Hypoxia is a hallmark of cancer. Hypoxia inducible factor-1 alpha (HIF-1 alpha) is the key regulator of the hypoxia response. HIF-1 alpha is overexpressed during sporadic breast carcinogenesis and correlated with poor prognosis. Little is known on the role of HIF-1 alpha in hereditary breast

  2. Role of macrophage inflammatory protein-1alpha in T-cell-mediated immunity to viral infection

    DEFF Research Database (Denmark)

    Madsen, Andreas N; Nansen, Anneline; Christensen, Jan P

    2003-01-01

    The immune response to lymphocytic choriomeningitis virus in mice lacking macrophage inflammatory protein-1alpha (MIP-1alpha) was evaluated. Generation of virus-specific effector T cells is unimpaired in MIP-1alpha-deficient mice. Furthermore, MIP-1alpha is not required for T-cell-mediated virus...... control or virus-induced T-cell-dependent inflammation. Thus, MIP-1alpha is not mandatory for T-cell-mediated antiviral immunity....

  3. High-fat feeding in cardiomyocyte-restricted PPARdelta knockout mice leads to cardiac overexpression of lipid metabolic genes but fails to rescue cardiac phenotypes.

    Science.gov (United States)

    Li, Yuquan; Cheng, Lihong; Qin, Qianhong; Liu, Jian; Lo, Woo-kuen; Brako, Lowrence A; Yang, Qinglin

    2009-10-01

    Peroxisome proliferator-activated receptor delta (PPARdelta) is an essential determinant of basal myocardial fatty acid oxidation (FAO) and bioenergetics. We wished to determine whether increased lipid loading affects the PPARdelta deficient heart in transcriptional regulation of FAO and in the development of cardiac pathology. Cardiomyocyte-restricted PPARdelta knockout (CR-PPARdelta(-/-)) and control (alpha-MyHC-Cre) mice were subjected to 48 h of fasting and to a long-term maintenance on a (28 weeks) high-fat diet (HFD). The expression of key FAO proteins in heart was examined. Serum lipid profiles, cardiac pathology, and changes of various transduction signaling pathways were also examined. Mice subjected to fasting exhibited upregulated transcript expression of FAO genes in the CR-PPARdelta(-/-) hearts. Moreover, long-term HFD in CR-PPARdelta(-/-) mice induced a strikingly greater transcriptional response. After HFD, genes encoding key FAO enzymes were expressed remarkably more in CR-PPARdelta(-/-) hearts than in those of control mice. Despite the marked rise of FAO gene expression, corresponding protein expression remained low in the CR-PPARdelta(-/-) heart, accompanied by abnormalities in sarcomere structures and mitochondria that were similar to those of CR-PPARdelta(-/-) hearts with regular chow feeding. The CR-PPARdelta(-/-) mice displayed increased expression of PPARgamma co-activator-1alpha (PGC-1alpha) and PPARalpha in the heart with deactivated Akt and p42/44 MAPK signaling in response to HFD. We conclude that PPARdelta is an essential determinant of myocardial FAO. Increased lipid intake activates cardiac expression of FAO genes via PPARalpha/PGC-1alpha pathway, albeit it is not sufficient to improve cardiac pathology due to PPARdelta deficiency.

  4. Murine elongation factor 1 alpha (EF-1 alpha) is posttranslationally modified by novel amide-linked ethanolamine-phosphoglycerol moieties. Addition of ethanolamine-phosphoglycerol to specific glutamic acid residues on EF-1 alpha

    International Nuclear Information System (INIS)

    Whiteheart, S.W.; Shenbagamurthi, P.; Chen, L.; Cotter, R.J.; Hart, G.W.

    1989-01-01

    Elongation Factor 1 alpha (EF-1 alpha), an important eukaryotic translation factor, transports charged aminoacyl-tRNA from the cytosol to the ribosomes during poly-peptide synthesis. Metabolic radiolabeling with [ 3 H] ethanolamine shows that, in all cells examined, EF-1 alpha is the major radiolabeled protein. Radiolabeled EF-1 alpha has an apparent Mr = 53,000 and a basic isoelectric point. It is cytosolic and does not contain N-linked oligosaccharides. Trypsin digestion of murine EF-1 alpha generated two major [ 3 H]ethanolamine-labeled peptides. Three peptides were sequenced and were identical to two distinct regions of the human EF-1 alpha protein. Blank sequencing cycles coinciding with glutamic acid in the human cDNA-derived sequence were also found to release [ 3 H]ethanolamine, and compositional analysis of these peptides confirmed the presence of glutamic acid. Dansylation analysis demonstrates that the amine group of the ethanolamine is blocked. These results indicate that EF-1 alpha is posttranslationally modified by the covalent attachment of ethanolamine via an amide bond to at least two specific glutamic acid residues (Glu-301 and Glu-374). The hydroxyl group of the attached ethanolamine was shown by mass spectrometry and compositional analysis, to be further modified by the addition of a phosphoglycerol unit. This novel posttranslational modification may represent an important alteration of EF-1 alpha, comparable to the regulatory effects of posttranslational methylation of EF-1 alpha lysine residues

  5. Structural and Functional Impacts of ER Coactivator Sequential Recruitment.

    Science.gov (United States)

    Yi, Ping; Wang, Zhao; Feng, Qin; Chou, Chao-Kai; Pintilie, Grigore D; Shen, Hong; Foulds, Charles E; Fan, Guizhen; Serysheva, Irina; Ludtke, Steven J; Schmid, Michael F; Hung, Mien-Chie; Chiu, Wah; O'Malley, Bert W

    2017-09-07

    Nuclear receptors recruit multiple coactivators sequentially to activate transcription. This "ordered" recruitment allows different coactivator activities to engage the nuclear receptor complex at different steps of transcription. Estrogen receptor (ER) recruits steroid receptor coactivator-3 (SRC-3) primary coactivator and secondary coactivators, p300/CBP and CARM1. CARM1 recruitment lags behind the binding of SRC-3 and p300 to ER. Combining cryo-electron microscopy (cryo-EM) structure analysis and biochemical approaches, we demonstrate that there is a close crosstalk between early- and late-recruited coactivators. The sequential recruitment of CARM1 not only adds a protein arginine methyltransferase activity to the ER-coactivator complex, it also alters the structural organization of the pre-existing ERE/ERα/SRC-3/p300 complex. It induces a p300 conformational change and significantly increases p300 HAT activity on histone H3K18 residues, which, in turn, promotes CARM1 methylation activity on H3R17 residues to enhance transcriptional activity. This study reveals a structural role for a coactivator sequential recruitment and biochemical process in ER-mediated transcription. Copyright © 2017 Elsevier Inc. All rights reserved.

  6. Dual roles for coactivator activator and its counterbalancing isoform coactivator modulator in human kidney cell tumorigenesis.

    Science.gov (United States)

    Kang, Yun Kyoung; Schiff, Rachel; Ko, Lan; Wang, Tao; Tsai, Sophia Y; Tsai, Ming-Jer; O'Malley, Bert W

    2008-10-01

    Coactivator activator (CoAA) has been reported to be a coactivator that regulates steroid receptor-mediated transcription and alternative RNA splicing. Herein, we show that CoAA is a dual-function coregulator that inhibits G(1)-S transition in human kidney cells and suppresses anchorage-independent growth and xenograft tumor formation. Suppression occurs in part by down-regulating c-myc and its downstream effectors ccnd1 and skp2 and causing accumulation of p27/Kip1 protein. In this cellular setting, CoAA directly represses the proto-oncogene c-myc by recruiting HDAC3 protein and decreasing both the acetylation of histone H3 and the presence of RNA polymerase II on the c-myc promoter. Interestingly, a splicing isoform of CoAA, coactivator modulator (CoAM), antagonizes CoAA-induced G(1)-S transition and growth inhibition by negatively regulating the mRNA levels of the endogenous CoAA isoform. In addition, we found that expression of CoAA protein is significantly decreased in human renal cell carcinoma compared with normal kidney. Our study presents evidence that CoAA is a potential tumor suppressor in renal carcinoma and that CoAM is a counterbalancing splice isoform. This is, thus far, the only example of a nuclear receptor coregulator involved in suppression of kidney cancer and suggests potentially significant new roles for coregulators in renal cancer biology.

  7. Trim24 (Tif1 alpha): an essential 'brake' for retinoic acid-induced transcription to prevent liver cancer.

    Science.gov (United States)

    Khetchoumian, Konstantin; Teletin, Marius; Tisserand, Johan; Herquel, Benjamin; Ouararhni, Khalid; Losson, Régine

    2008-12-01

    Retinoic acid (RA), the active derivative of vitamin A, is an important signaling molecule that controls various developmental processes and influence the proliferation and differentiation of a variety of cell types. RA exerts its biological functions primarily through binding to and activating nuclear RA receptors (RARs, which include the RAR alpha, beta and gamma isotypes RARA, RARB and RARC). Aberrant expression or impaired function of these nuclear receptors has been linked to diverse types of cancer. RARs are RA-dependent transcription factors that regulate gene expression through the recruitment of different co-regulators (co-activators and co-repressors). TRIM24 (formerly known as TIF1 alpha) was among the first co-regulators identified as interacting with RARs in a ligand-dependent fashion, and it was recently shown to function in mice as a potent liver-specific tumor suppressor by attenuating Rara-mediated transcription. The fact that Trim24(-/-), but not Trim24(-/-)Rara(+/-), mutant mice are highly predisposed to the development of hepatocellular carcinoma (HCC) has significant implications in cancer research. This result, along with the observation that in response to pharmacological inhibition of the RA signaling, hepatocytes lacking Trim24 loose their ability to proliferate, strongly implicates Rara as a proto-oncogene in hepatocytes and demonstrates that overactivated RA signaling is deleterious to liver homeostasis.

  8. An Extension of SIC Predictions to the Wiener Coactive Model.

    Science.gov (United States)

    Houpt, Joseph W; Townsend, James T

    2011-06-01

    The survivor interaction contrasts (SIC) is a powerful measure for distinguishing among candidate models of human information processing. One class of models to which SIC analysis can apply are the coactive, or channel summation, models of human information processing. In general, parametric forms of coactive models assume that responses are made based on the first passage time across a fixed threshold of a sum of stochastic processes. Previous work has shown that that the SIC for a coactive model based on the sum of Poisson processes has a distinctive down-up-down form, with an early negative region that is smaller than the later positive region. In this note, we demonstrate that a coactive process based on the sum of two Wiener processes has the same SIC form.

  9. Muscle Co-activation: Definitions, Mechanisms, and Functions.

    Science.gov (United States)

    Latash, Mark L

    2018-03-28

    The phenomenon of agonist-antagonist muscle co-activation is discussed with respect to its consequences for movement mechanics (such as increasing joint apparent stiffness, facilitating faster movements, and effects on action stability), implication for movement optimization, and involvement of different neurophysiological structures. Effects of co-activation on movement stability are ambiguous and depend on the effector representing a kinematic chain with a fixed origin or free origin. Further, co-activation is discussed within the framework of the equilibrium-point hypothesis and the idea of hierarchical control with spatial referent coordinates. Relations of muscle co-activation to changes in one of the basic commands, the c-command, are discussed and illustrated. A hypothesis is suggested that agonist-antagonist co-activation reflects a deliberate neural control strategy to preserve effector-level control and avoid making it degenerate and facing the necessity to control at the level of signals to individual muscles. This strategy, in particular, allows stabilizing motor actions by co-varied adjustments in spaces of control variables. This hypothesis is able to account for higher levels of co-activation in young healthy persons performing challenging tasks and across various populations with movement impairments.

  10. Reactivation of the chloroplast CF1-ATPase beta subunit by trace amounts of the CF1 alpha subunit suggests a chaperonin-like activity for CF1 alpha.

    Science.gov (United States)

    Avni, A; Avital, S; Gromet-Elhanan, Z

    1991-04-25

    Incubation of tobacco and lettuce thylakoids with 2 M LiCl in the presence of MgATP removes the beta subunit from their CF1-ATPase (CF1 beta) together with varying amounts of the CF1 alpha subunit (CF1 alpha). These 2 M LiCl extracts, as with the one obtained from spinach thylakoids (Avital, S., and Gromet-Elhanan, Z. (1991) J. Biol. Chem. 266, 7067-7072), could form active hybrid ATPases when reconstituted into inactive beta-less Rhodospirillum rubrum chromatophores. Pure CF1 beta fractions that have been isolated from these extracts could not form such active hybrids by themselves, but could do so when supplemented with trace amounts (less than 5%) of CF1 alpha. A mitochondrial F1-ATPase alpha subunit was recently reported to be a heat-shock protein, having two amino acid sequences that show a highly conserved identity with sequences found in molecular chaperones (Luis, A. M., Alconada, A., and Cuezva, J. M. (1990) J. Biol. Chem. 265, 7713-7716). These sequences are also conserved in CF1 alpha isolated from various plants, but not in F1 beta subunits. The above described reactivation of CF1 beta by trace amounts of CF1 alpha could thus be due to a chaperonin-like function of CF1 alpha, which involves the correct, active folding of isolated pure CF1 beta.

  11. Acute effect of oral, intraperitoneal, and intravenous 1 alpha-hydroxycholecalciferol on markers of bone metabolism

    DEFF Research Database (Denmark)

    Joffe, P; Ladefoged, S D; Cintin, C

    1994-01-01

    ,25-(OH)2D3 was measured. DESIGN: Single doses of 1 alpha-OHD3 (80 ng/kg body wt) were given in randomized cross-over fashion, orally, intraperitoneally (i.p.) and intravenously (i.v.) on three occasions. Blood was sampled at 0, 1, 6, 12, and 24 h after administration of 1 alpha-OHD3. MAIN RESULTS...

  12. IgG autoantibodies against interleukin 1 alpha in sera of normal individuals

    DEFF Research Database (Denmark)

    Svenson, M; Poulsen, L K; Fomsgaard, A

    1989-01-01

    A pool of human sera from healthy blood donors was found to interfere competitively with the binding of 125I-labelled human recombinant interleukin 1 alpha (rIL-1 alpha) to the murine T-cell line EL4. The interference was reversible at the cellular level, and direct binding of the ligand to serum...

  13. Hypoxia-inducible factor-1 alpha has a key role in hypoxic preconditioning.

    Science.gov (United States)

    Taie, Satoshi; Ono, Junichiro; Iwanaga, Yasuyuki; Tomita, Shuhei; Asaga, Takehiko; Chujo, Kosuke; Ueki, Masaaki

    2009-08-01

    Sublethal hypoxia induces tolerance to subsequent hypoxic insults in a process known as hypoxic preconditioning (HP). Hypoxia-inducible factor-1 alpha (HIF-1 alpha) is a key transcription protein involved in the mechanism of HP. In this study, we investigated the effects of HP on tissue oxygenation and expression of HIF-1 alpha gene targets in the brain using neural cell-specific HIF-1 alpha-deficient mice. The animals were exposed to 8% oxygen for 3 hours. Twenty-four hours later, the oxygen partial pressure (pO(2)) of brain tissue and gene expression were measured during hypoxia. HP improved the pO(2) of brain tissue during subsequent hypoxia with upregulated inducible nitric oxide synthase in wild-type mice, whereas HP had no detectable effect in the mutant mice. Our results indicate that the protective effects of HP may be partially mediated by improving tissue oxygenation via HIF-1 alpha and inducible nitric oxide synthase.

  14. Prognostic impact of HIF-1{alpha} expression in patients with definitive radiotherapy for cervical cancer

    Energy Technology Data Exchange (ETDEWEB)

    Dellas, K.; Bache, M.; Kappler, M.; Haensgen, G. [Halle-Wittenberg Univ., Halle (Germany). Dept. of Radiotherapy; Pigorsch, S.U. [Technische Univ. Muenchen (Germany). Dept. of Radiotherapy and Radiation Oncology; Taubert, H.; Holzhausen, H.J. [Halle-Wittenberg Univ., Halle (Germany). Inst. of Pathology; Holzapfel, D.; Zorn, E. [Halle-Wittenberg Univ., Halle (Germany). Dept. of Radiotherapy; Halle-Wittenberg Univ., Halle (Germany). Inst. of Pathology

    2008-03-15

    Purpose: To investigate the relationship between the hypoxia-inducible factor-(HIF-)1{alpha} expression in tumor tissue, tumor oxygenation and hemoglobin levels in patients with advanced cervical cancers prior to radiotherapy and the effect on clinical outcome. Patients and Methods: The investigation included 44 patients who underwent definitive radiotherapy for advanced cervical cancers between May 1995 and March 1999. Tumor biopsies were taken prior to treatment, and HIF-1{alpha} expression was determined by immunohistochemistry. In the same tumor area, tumor tissue oxygenation (pO{sub 2}) was measured using the Eppendorf device. Results: The 5-year cancer-specific survival of all patients was 60%. Twelve of 44 tumor specimens were HIF-1{alpha}-negative with a significantly better 5-year survival (92 {+-} 8%) versus 32 patients who were HIF-1{alpha}-positive (45 {+-} 10%; p < 0.02). There was no correlation between HIF-1{alpha} expression and tumor oxygenation (p = 0.57 both for pO{sub 2} median and hypoxic fraction < 5 mmHg vs. HIF-1{alpha} expression). However, patients with hemoglobin levels < 11 g/dl showed elevated HIF-1{alpha} expression compared to patients with hemoglobin levels > 12.5 g/dl (p = 0.04). Furthermore, HIF-1{alpha} correlated with vascular endothelial growth factor expression (p = 0.002). In a multivariate Cox regression model, HIF-1{alpha} expression (relative risk [RR] = 7.5; p = 0.05) revealed an increased risk of tumor-related death. Conclusion: The study indicates, that endogenous tumor markers such as HIF-1{alpha} may serve as prognostic markers of clinical outcome concerning cervical cancer after primary radiotherapy. (orig.)

  15. Effect of regional muscle location but not adiposity on mitochondrial biogenesis-regulating proteins

    DEFF Research Database (Denmark)

    Ponce-González, Jesús Gustavo; Ara, Ignacio; Larsen, Steen

    2016-01-01

    PURPOSE: The aim of this study was to determine if the expression of the mitochondrial biogenesis-regulating proteins SIRT1, SIRT3 and PGC-1alpha in human skeletal muscle is influenced by adiposity. METHOD: Twenty-nine male subjects were recruited into three groups: control (n = 10), obese (n = 10...

  16. Coactive Design : Designing Support for Interdependence in Joint Activity

    NARCIS (Netherlands)

    Johnson, M.; Bradshaw, J.M.; Feltovich, P.J.; Jonker, C.M.; Van Riemsdijk, M.B.; Sierhuis, M.

    2014-01-01

    Coactive Design is a new approach to address the increasingly sophisticated roles that people and robots play as the use of robots expands into new, complex domains. The approach is motivated by the desire for robots to perform less like teleoperated tools or independent automatons and more like

  17. SDF-1 alpha expression during wound healing in the aged is HIF dependent.

    Science.gov (United States)

    Loh, Shang A; Chang, Edward I; Galvez, Michael G; Thangarajah, Hariharan; El-ftesi, Samyra; Vial, Ivan N; Lin, Darius A; Gurtner, Geoffrey C

    2009-02-01

    Age-related impairments in wound healing are associated with decreased neovascularization, a process that is regulated by hypoxia-responsive cytokines, including stromal cell-derived factor (SDF)-1 alpha. Interleukin-1 beta is an important inflammatory cytokine involved in wound healing and is believed to regulate SDF-1 alpha expression independent of hypoxia signaling. Thus, the authors examined the relative importance of interleukin (IL)-1 beta and hypoxia-inducible factor (HIF)-1 alpha on SDF-1 alpha expression in aged wound healing. Young and aged mice (n = 4 per group) were examined for wound healing using a murine excisional wound model. Wounds were harvested at days 0, 1, 3, 5, and 7 for histologic analysis, immunohistochemistry, enzyme-linked immunosorbent assay, and Western blot. An engineered wild-type and mutated SDF luciferase reporter construct were used to determine HIF transactivation. Aged mice demonstrated significantly impaired wound healing, reduced granulation tissue, and increased epithelial gap compared with young controls. Real-time polymerase chain reaction demonstrated reduced SDF-1 alpha levels in aged wounds that correlated with reduced CD31+ neovessels. Western blots revealed decreased HIF-1 alpha protein in aged wounds. However, both IL-1 beta and macrophage infiltrate were unchanged between young and aged animals. Using the wild-type and mutated SDF luciferase reporter construct in which the hypoxia response element was deleted, only young fibroblasts were able to respond to IL-1 beta stimulation, and this response was abrogated by mutating the HIF-binding sites. This suggests that HIF binding is essential for SDF-1 transactivation in response to both inflammatory and hypoxic stimuli. SDF-1 alpha deficiency observed during aged wound healing is attributable predominantly to decreased HIF-1 alpha levels rather than impaired IL-1 beta expression.

  18. Whole-body irradiation transiently diminishes the adrenocorticotropin response to recombinant human interleukin-1{alpha}

    Energy Technology Data Exchange (ETDEWEB)

    Perlstein, R.S.; Mehta, N.R.; Neta, R.; Whitnall, M.H. [Armed Forces Radiobiology Research Institute, Bethesda, MD (United States); Mougey, E.H. [Walter Reed Army Institute of Research, Washington, DC (United States)

    1995-03-01

    Recombinant human interleukin-1{alpha} (rhIL-1{alpha}) has significant potential as a radioprotector and/or treatment for radiation-induced hematopoietic injury. Both IL-1 and whole-body ionizing irradiation acutely stimulate the hypothalamic-pituitary-adrenal axis. We therefore assessed the interaction of whole-body irradiation and rhIL-1{alpha} in altering the functioning of the axis in mice. Specifically, we determined the adrenocorticotropin (ACTH) and corticosterone responses to rhIL-1{alpha} administered just before and hours to days after whole-body or sham irradiation. Our results indicate that whole-body irradiation does not potentiate the rhIL-1{alpha}-induced increase in ACTH levels at the doses used. In fact, the rhIL-1{alpha}-induced increase in plasma ACTH is transiently impaired when the cytokine is administered 5 h after, but not 1 h before, exposure to whole-body irradiation. The ACTH response may be inhibited by elevated corticosterone levels after whole-body irradiation, or by other radiation-induced effects on the pituitary gland and hypothalamus. 36 refs., 3 figs.

  19. Macrophage inflammatory protein-1alpha: a link between innate immunity and familial Mediterranean fever?

    Science.gov (United States)

    Dizdar, Omer; Kalyoncu, Umut; Karadag, Omer; Akdogan, Ali; Kiraz, Sedat; Ertenli, Ihsan; Barista, Ibrahim; Calguneri, Meral

    2007-01-01

    The aim of this study is to investigate the relationship between chemokines and the inflammation in Familial Mediterranean Fever (FMF). Forty-nine patients with FMF (41 in remission and 8 in acute attack period) and 20 healthy controls were included in the study. Serum levels of macrophage inflammatory protein-1alpha (MIP-1alpha) were assessed in the patients and the controls, along with other parameters of disease activity, i.e., fibrinogen, C-reactive protein and erythrocyte sedimentation rate. Serum MIP-1alpha levels of the patients with FMF in acute attack period were significantly higher than the patients in remission and healthy controls (p=0.02 and p=0.038, respectively). MIP-1alpha levels were weakly correlated with CRP (r=0.32, p=0.032) levels. MIP-1alpha may have a role in the pathogenesis of FMF attacks. MIP-1alpha and other chemokines may constitute a link between the innate immune system and FMF.

  20. DAX1 suppresses FXR transactivity as a novel co-repressor

    Energy Technology Data Exchange (ETDEWEB)

    Li, Jin; Lu, Yan; Liu, Ruya; Xiong, Xuelian; Zhang, Zhijian; Zhang, Xianfeng [Shanghai Clinical Center for Endocrine and Metabolic Diseases, Shanghai Institute of Endocrine and Metabolic Diseases, Department of Endocrinology and Metabolism, Rui-Jin Hospital, Shanghai Jiao-Tong University School of Medicine, Shanghai 200025 (China); Ning, Guang, E-mail: guangning@gmail.com.cn [Shanghai Clinical Center for Endocrine and Metabolic Diseases, Shanghai Institute of Endocrine and Metabolic Diseases, Department of Endocrinology and Metabolism, Rui-Jin Hospital, Shanghai Jiao-Tong University School of Medicine, Shanghai 200025 (China); The Key Laboratory of Endocrine Tumors and The Division of Endocrine and Metabolic Diseases, E-Institute of Shanghai Universities, Shanghai 200025 (China); Li, Xiaoying, E-mail: lixy@sibs.ac.cn [Shanghai Clinical Center for Endocrine and Metabolic Diseases, Shanghai Institute of Endocrine and Metabolic Diseases, Department of Endocrinology and Metabolism, Rui-Jin Hospital, Shanghai Jiao-Tong University School of Medicine, Shanghai 200025 (China); The Key Laboratory of Endocrine Tumors and The Division of Endocrine and Metabolic Diseases, E-Institute of Shanghai Universities, Shanghai 200025 (China)

    2011-09-09

    Highlights: {yields} DAX1 is co-localized with FXR and interacts with FXR. {yields} DAX1 acts as a negative regulator of FXR. {yields} Three LXXLL motifs in the N-terminus of DAX1 were required. {yields} DAX1 suppresses FXR transactivation by competing with co-activators. -- Abstract: Bile acid receptor FXR (farnesoid X receptor) is a key regulator of hepatic bile acid, glucose and lipid homeostasis through regulation of numerous genes involved in the process of bile acid, triglyceride and glucose metabolism. DAX1 (dosage-sensitive sex reversal adrenal hypoplasia congenital critical region on X chromosome, gene 1) is an atypical member of the nuclear receptor family due to lack of classical DNA-binding domains and acts primarily as a co-repressor of many nuclear receptors. Here, we demonstrated that DAX1 is co-localized with FXR in the nucleus and acted as a negative regulator of FXR through a physical interaction with FXR. Our study showed that over-expression of DAX1 down-regulated the expression of FXR target genes, whereas knockdown of DAX1 led to their up-regulation. Furthermore, three LXXLL motifs in the N-terminus of DAX1 were required for the full repression of FXR transactivation. In addition, our study characterized that DAX1 suppresses FXR transactivation via competing with co-activators such as SRC-1 and PGC-1{alpha}. In conclusion, DAX1 acts as a co-repressor to negatively modulate FXR transactivity.

  1. Unmanned Tactical Autonomous Control and Collaboration Coactive Design

    Science.gov (United States)

    2016-06-01

    process. When modeling processes with a waterfall design, the requirements are mostly understood upfront and allow developers to move on to subsequent...processes when modeling the system. As such, the focus is shifted to supplementing team capacities vice developing autonomy. The two aims of this...development method, Coactive Design. An advantage to using this method is that it includes the human and his or her internal processes when modeling the

  2. Long-term fasting decreases mitochondrial avian UCP-mediated oxygen consumption in hypometabolic king penguins.

    Science.gov (United States)

    Rey, Benjamin; Halsey, Lewis G; Dolmazon, Virginie; Rouanet, Jean-Louis; Roussel, Damien; Handrich, Yves; Butler, Patrick J; Duchamp, Claude

    2008-07-01

    In endotherms, regulation of the degree of mitochondrial coupling affects cell metabolic efficiency. Thus it may be a key contributor to minimizing metabolic rate during long periods of fasting. The aim of the present study was to investigate whether variation in mitochondrial avian uncoupling proteins (avUCP), as putative regulators of mitochondrial oxidative phosphorylation, may contribute to the ability of king penguins (Aptenodytes patagonicus) to withstand fasting for several weeks. After 20 days of fasting, king penguins showed a reduced rate of whole animal oxygen consumption (Vo2; -33%) at rest, together with a reduced abundance of avUCP and peroxisome proliferator-activated receptor-gamma coactivator-1alpha (PGC1-alpha) mRNA in pectoralis muscle (-54%, -36%, respectively). These parameters were restored after the birds had been refed for 3 days. Furthermore, in recently fed, but not in fasted penguins, isolated muscle mitochondria showed a guanosine diphosphate-inhibited, fatty acid plus superoxide-activated respiration, indicating the presence of a functional UCP. It was calculated that variation in mitochondrial UCP-dependent respiration in vitro may contribute to nearly 20% of the difference in resting Vo2 between fed or refed penguins and fasted penguins measured in vivo. These results suggest that the lowering of avUCP activity during periods of long-term energetic restriction may contribute to the reduction in metabolic rate and hence the ability of king penguins to face prolonged periods of fasting.

  3. Steroid receptor coactivator-3 regulates glucose metabolism in bladder cancer cells through coactivation of hypoxia inducible factor 1α.

    Science.gov (United States)

    Zhao, Wei; Chang, Cunjie; Cui, Yangyan; Zhao, Xiaozhi; Yang, Jun; Shen, Lan; Zhou, Ji; Hou, Zhibo; Zhang, Zhen; Ye, Changxiao; Hasenmayer, Donald; Perkins, Robert; Huang, Xiaojing; Yao, Xin; Yu, Like; Huang, Ruimin; Zhang, Dianzheng; Guo, Hongqian; Yan, Jun

    2014-04-18

    Cancer cell proliferation is a metabolically demanding process, requiring high glycolysis, which is known as "Warburg effect," to support anabolic growth. Steroid receptor coactivator-3 (SRC-3), a steroid receptor coactivator, is overexpressed and/or amplified in multiple cancer types, including non-steroid targeted cancers, such as urinary bladder cancer (UBC). However, whether SRC-3 regulates the metabolic reprogramming for cancer cell growth is unknown. Here, we reported that overexpression of SRC-3 accelerated UBC cell growth, accompanied by the increased expression of genes involved in glycolysis. Knockdown of SRC-3 reduced the UBC cell glycolytic rate under hypoxia, decreased tumor growth in nude mice, with reduction of proliferating cell nuclear antigen and lactate dehydrogenase expression levels. We further revealed that SRC-3 could interact with hypoxia inducible factor 1α (HIF1α), which is a key transcription factor required for glycolysis, and coactivate its transcriptional activity. SRC-3 was recruited to the promoters of HIF1α-target genes, such as glut1 and pgk1. The positive correlation of expression levels between SRC-3 and Glut1 proteins was demonstrated in human UBC patient samples. Inhibition of glycolysis through targeting HK2 or LDHA decelerated SRC-3 overexpression-induced cell growth. In summary, overexpression of SRC-3 promoted glycolysis in bladder cancer cells through HIF1α to facilitate tumorigenesis, which may be an intriguing drug target for bladder cancer therapy.

  4. Catabolism of 6-ketoprostaglandin F1alpha by the rat kidney cortex.

    Science.gov (United States)

    Pace-Asciak, C R; Domazet, Z; Carrara, M

    1977-05-25

    Homogenates of the rat kidney cortex converted 5,8,9,11,12,14,15-hepta-tritiated 6-ketoprostaglandin F 1alpha into one major product identified by gas chromatography-mass spectrometry of the methoxime-methyl ester trimethylsilyl ether derivative as 6,15-diketo-9,11-dihydroxyprost-13-enoic acid. The sequence of derivatisation i.e. methoximation prior to methylation, was crucial as methylation of 15-keto catabolites of the E, F and 6-keto-F series affords degradation products. The corresponding 15-keto-13,14-dihydro catabolite was formed in much smaller quantities. Time course studies indicated that 6-keto-prostaglandin F1alpha was catabolised at a slower rate (about 2-5 fold) than prostaglandin F1alpha. The catabolic activity was blocked by NADH.

  5. Immunodetection of Thyroid Hormone Receptor (Alpha1/Alpha2) in the Rat Uterus and Oviduct

    International Nuclear Information System (INIS)

    Öner, Jale; Öner, Hakan

    2007-01-01

    The aim of this study was to investigate the immunolocalization and the existence of thyroid hormone receptors (THR) (alpha1/alpha2) in rat uterus and oviduct. For this purpose 6 female Wistar albino rats found in estrous period were used. Tissue samples fixed in 10% neutral formalin were examined immunohistochemically. Sections were incubated with primary mouse-monoclonal THR (alpha1/alpha2) antibody. In uterus, THR (alpha1/alpha2) immunoreacted strongly with uterine luminal epithelium, endometrial gland epithelium and endometrial stromal cells and, moderately with myometrial smooth muscle. In oviduct, they were observed moderately in the epithelium of the tube and the smooth muscle cells of the muscular layer. In conclusion, the presence of THR in uterus and oviduct suggests that these organs are an active site of thyroid hormones

  6. HIF-1{alpha} is necessary to support gluconeogenesis during liver regeneration

    Energy Technology Data Exchange (ETDEWEB)

    Tajima, Toshihide [Department of Obstetrics and Gynecology, School of Medicine, Keio University, 35 Shinanomachi, Shinjuku-ku, Tokyo 160-8582 (Japan); Goda, Nobuhito, E-mail: goda@waseda.jp [Department of Life Science and Medical Bio-Science, School of Advanced Science and Engineering, Waseda University, TWIns 2-2 Wakamatsu-cho, Shinjuku-ku, Tokyo 162-8480 (Japan); Fujiki, Natsuko; Hishiki, Takako; Nishiyama, Yasumasa [Department of Biochemistry and Integrative Medical Biology, School of Medicine, Keio University, 35 Shinanomachi, Shinjuku-ku, Tokyo 160-8582 (Japan); Senoo-Matsuda, Nanami [Department of Life Science and Medical Bio-Science, School of Advanced Science and Engineering, Waseda University, TWIns 2-2 Wakamatsu-cho, Shinjuku-ku, Tokyo 162-8480 (Japan); Shimazu, Motohide [Department of Surgery, Tokyo Medical University Hachioji Medical Center, 1163 Tatemachi, Hachioji, Tokyo 193-0998 (Japan); Soga, Tomoyoshi [The Institute for Advanced Biosciences, Keio University, Tsuruoka City, Yamagata 997-0052 (Japan); Yoshimura, Yasunori [Department of Obstetrics and Gynecology, School of Medicine, Keio University, 35 Shinanomachi, Shinjuku-ku, Tokyo 160-8582 (Japan); Johnson, Randall S. [Molecular Biology Section, Division of Biology, University of California, San Diego, La Jolla, CA 92093 (United States); Suematsu, Makoto [Department of Biochemistry and Integrative Medical Biology, School of Medicine, Keio University, 35 Shinanomachi, Shinjuku-ku, Tokyo 160-8582 (Japan)

    2009-10-02

    Coordinated recovery of hepatic glucose metabolism is prerequisite for normal liver regeneration. To examine roles of hypoxia inducible factor-1{alpha} (HIF-1{alpha}) for hepatic glucose homeostasis during the reparative process, we inactivated the gene in hepatocytes in vivo. Following partial hepatectomy (PH), recovery of residual liver weight was initially retarded in the mutant mice by down-regulation of hepatocyte proliferation, but occurred comparably between the mutant and control mice at 72 h after PH. At this time point, the mutant mice showed lowered blood glucose levels with enhanced accumulation of glycogen in the liver. The mutant mice exhibited impairment of hepatic gluconeogenesis as assessed by alanine tolerance test. This appeared to result from reduced expression of PGK-1 and PEPCK since 3-PG, PEP and malate were accumulated to greater extents in the regenerated liver. In conclusion, these findings provide evidence for roles of HIF-1{alpha} in the regulation of gluconeogenesis under liver regeneration.

  7. TIF1alpha: a possible link between KRAB zinc finger proteins and nuclear receptors

    DEFF Research Database (Denmark)

    Le Douarin, B; You, J; Nielsen, Anders Lade

    1998-01-01

    Ligand-induced gene activation by nuclear receptors (NRs) is thought to be mediated by transcriptional intermediary factors (TIFs), that interact with their ligand-dependent AF-2 activating domain. Included in the group of the putative AF-2 TIFs identified so far is TIF1alpha, a member of a new...... family of proteins which contains an N-terminal RBCC (RING finger-B boxes-coiled coil) motif and a C-terminal bromodomain preceded by a PHD finger. In addition to these conserved domains present in a number of transcriptional regulatory proteins, TIF1alpha was found to contain several protein......-protein interaction sites. Of these, one specifically interacts with NRs bound to their agonistic ligand and not with NR mutants that are defective in the AF-2 activity. Immediately adjacent to this 'NR box', TIF1alpha contains an interaction site for members of the chromatin organization modifier (chromo) family, HP...

  8. Topical N-acetylcysteine reduces interleukin-1-alpha in tear fluid after laser subepithelial keratectomy.

    Science.gov (United States)

    Urgancioglu, Berrak; Bilgihan, Kamil; Engin, Doruk; Cirak, Meltem Yalinay; Hondur, Ahmet; Hasanreisoglu, Berati

    2009-01-01

    To evaluate the effect of topical N-acetylcysteine (NAC) on interleukin 1-alpha (IL-1alpha) levels in tear fluid after myopic laser subepithelial keratectomy (LASEK) and its possible role in modulating corneal wound healing. Twenty-six eyes of 13 patients who underwent myopic LASEK were divided into 2 groups. Group 1 (n=10 eyes) was used as a control group. All patients received topical lomefloxacin and dexamethasone postoperatively. Additionally, patients in Group 2 received topical NAC for 1 month postoperatively. Tear fluid samples were collected with microcapillary tubes preoperatively, on the first and on the fifth postoperative day, and the release of IL-1alpha in tear fluid was calculated. Haze grading and confocal microscopic examination were performed at 1 and 3 months postoperatively. The mean IL-1-alpha release values were 0.285-/+0.159 pg/min in Group 1 and 0.235-/+0.142 pg/min in Group 2 preoperatively. In Group 1, the values were 0.243-/+0.155 pg/min on day 1 and 0.164-/+0.125 pg/min on day 5. In Group 2, the mean IL-1alpha release values were 0.220-/+0.200 pg/min on day 1 and 0.080-/+0.079 pg/min on day 5. The difference between the groups was significant only for day 5 (p0.05). NAC seems to have an additive effect to steroids in suppressing IL-1alpha levels in tear fluid and may be clinically advantageous in modulating corneal wound healing during the early postoperative period after LASEK.

  9. Expression of HIF-1{alpha} in irradiated tissue is altered by topical negative-pressure therapy

    Energy Technology Data Exchange (ETDEWEB)

    Grimm, A.; Stange, S.; Labanaris, A.; Horch, R.E. [Erlangen-Nuernberg Univ., Erlangen (Germany). Dept. of Plastic and Hand Surgery; Dimmler, A. [Erlangen-Nuernberg Univ., Erlangen (Germany). Dept. of Pathology; Sauer, R.; Grabenbauer, G. [Erlangen-Nuernberg Univ. (Germany). Dept. of Radiation Oncology

    2007-03-15

    Background and Purpose: Despite the enormous therapeutic potential of modern radiotherapy, common side effects such as radiation-induced wound healing disorders remain a well-known clinical phenomenon. Topical negative pressure therapy (TNP) is a novel tool to alleviate intraoperative, percutaneous irradiation or brachytherapy. Since TNP has been shown to positively influence the perfusion of chronic, poorly vascularized wounds, the authors applied this therapeutic method to irradiated wounds and investigated the effect on tissue oxygenation in irradiated tissue in five patients. Material and Methods: With informed patients' consent, samples prior to and 4 and 8 days after continuous TNP with -125 mmHg were obtained during routine wound debridements. Granulation tissue was stained with hematoxylin-eosin, and additionally with CD31, HIF-1{alpha} (hypoxia-inducible factor-1{alpha}), and D2-40 to detect blood vessels, measure indirect signs of hypoxia, and lymph vessel distribution within the pre- and post-TNP samples. Results: In this first series of experiments, a positive influence of TNP onto tissue oxygenation in radiation-induced wounds could be demonstrated. TNP led to a significant decrease of 53% HIF-1{alpha}-positive cell nuclei. At the same time, a slight reduction of CD31-stained capillaries was seen in comparison to samples before TNP. Immunostaining with D2-40 revealed an increased number of lymphatic vessels with distended lumina and an alteration of the parallel orientation within the post-TNP samples. Conclusion: This study is, to the authors' knowledge, the first report on a novel previously not described histological marker to demonstrate the effects of TNP on HIF-1{alpha} expression as an indirect marker of tissue oxygenation in irradiated wounds, as demonstrated by a reduction of HIF-1{alpha} concentration after TNP. Since this observation may be of significant value to develop possible new strategies to treat radiation-induced tissue

  10. HNF1 alpha activates the aminopeptidase N promoter in intestinal (Caco-2) cells

    DEFF Research Database (Denmark)

    Olsen, Jørgen; Laustsen, Lotte; Troelsen, J

    1994-01-01

    The importance of HNF1 binding proteins for intestinal aminopeptidase N expression was investigated using the Caco-2 cell-line. Aminopeptidase N promoter activity in Caco-2 cells depends on the HNF1 element (positions -85 to -58) and co-transfection with an HNF1 alpha expression vector demonstrates...... a direct activation of the promoter by HNF1 alpha through this element. Electrophoretic mobility shift assays using nuclear extracts from Caco-2 cells show the presence of high amounts of HNF1 binding proteins irrespective of their state of differentiation....

  11. Development of a bioassay to screen for chemicals mimicking the anti-aging effects of calorie restriction

    Energy Technology Data Exchange (ETDEWEB)

    Chiba, Takuya, E-mail: takuya@nagasaki-u.ac.jp [Department of Investigative Pathology, Graduate School of Biomedical Sciences, Nagasaki University, 1-12-4 Sakamoto, Nagasaki 852-8523 (Japan); Tsuchiya, Tomoshi [Division of Surgical Oncology, Graduate School of Biomedical Sciences, Nagasaki University, 1-7-1 Sakamoto, Nagasaki 852-8501 (Japan); Komatsu, Toshimitsu; Mori, Ryoichi; Hayashi, Hiroko [Department of Investigative Pathology, Graduate School of Biomedical Sciences, Nagasaki University, 1-12-4 Sakamoto, Nagasaki 852-8523 (Japan); Shimano, Hitoshi [Department of Internal Medicine (Endocrinology and Metabolism), Graduate School of Comprehensive Human Sciences, University of Tsukuba, 1-1-1 Tennodai, Tsukuba Ibaraki 305-8575 (Japan); Spindler, Stephen R. [Department of Biochemistry, Room 5478, Boyce Hall, University of California - Riverside, Riverside, CA 92521 (United States); Shimokawa, Isao [Department of Investigative Pathology, Graduate School of Biomedical Sciences, Nagasaki University, 1-12-4 Sakamoto, Nagasaki 852-8523 (Japan)

    2010-10-15

    Research highlights: {yields} We identified four sequence motifs lying upstream of putative pro-longevity genes. {yields} One of these motifs binds to HNF-4{alpha}. {yields} HNF-4{alpha}/PGC-1{alpha} could up-regulate the transcription of a reporter gene linked to this motif. {yields} The reporter system described here could be used to screen candidate anti-aging molecules. -- Abstract: Suppression of the growth hormone/insulin-like growth factor-I pathway in Ames dwarf (DF) mice, and caloric restriction (CR) in normal mice extends lifespan and delays the onset of age-related disorders. In combination, these interventions have an additive effect on lifespan in Ames DF mice. Therefore, common signaling pathways regulated by DF and CR could have additive effects on longevity. In this study, we tried to identity the signaling mechanism and develop a system to assess pro-longevity status in cells and mice. We previously identified genes up-regulated in the liver of DF and CR mice by DNA microarray analysis. Motif analysis of the upstream sequences of those genes revealed four major consensus sequence motifs, which have been named dwarfism and calorie restriction-responsive elements (DFCR-REs). One of the synthesized sequences bound to hepatocyte nuclear factor-4{alpha} (HNF-4{alpha}), an important transcription factor involved in liver metabolism. Furthermore, using this sequence information, we developed a highly sensitive bioassay to identify chemicals mimicking the anti-aging effects of CR. When the reporter construct, containing an element upstream of a secreted alkaline phosphatase (SEAP) gene, was co-transfected with HNF-4{alpha} and its regulator peroxisome proliferator-activated receptor (PPAR) {gamma} coactivator-1{alpha} (PGC-1{alpha}), SEAP activity was increased compared with untransfected controls. Moreover, transient transgenic mice established using this construct showed increased SEAP activity in CR mice compared with ad libitum-fed mice. These data

  12. A RNA antagonist of hypoxia-inducible factor-1alpha, EZN-2968, inhibits tumor cell growth

    DEFF Research Database (Denmark)

    Greenberger, Lee M; Horak, Ivan D; Filpula, David

    2008-01-01

    Hypoxia-inducible factor-1 (HIF-1) is a transcription factor that plays a critical role in angiogenesis, survival, metastasis, drug resistance, and glucose metabolism. Elevated expression of the alpha-subunit of HIF-1 (HIF-1alpha), which occurs in response to hypoxia or activation of growth facto...

  13. Inhibition of HIF-1{alpha} activity by BP-1 ameliorates adjuvant induced arthritis in rats

    Energy Technology Data Exchange (ETDEWEB)

    Shankar, J. [Department of Microbiology and Immunology, University of Illinois at Chicago, Chicago (United States); Thippegowda, P.B., E-mail: btprabha@uic.edu [Department of Pharmacology, (M/C 868), College of Medicine, University of Illinois at Chicago, 835 S. Wolcott Ave., Chicago, IL 60612 (United States); Kanum, S.A. [Department of Chemistry, Yuvaraj' s College, University of Mysore, Mysore (India)

    2009-09-18

    Rheumatoid arthritis (RA) is a chronic inflammatory, angiogenic disease. Inflamed synovitis is a hallmark of RA which is hypoxic in nature. Vascular endothelial growth factor (VEGF), one of the key regulators of angiogenesis, is overexpressed in the pathogenesis of RA. VEGF expression is regulated by hypoxia-inducible factor-1{alpha} (HIF-1{alpha}), a master regulator of homeostasis which plays a pivotal role in hypoxia-induced angiogenesis. In this study we show that synthetic benzophenone analogue, 2-benzoyl-phenoxy acetamide (BP-1) can act as a novel anti-arthritic agent in an experimental adjuvant induced arthritis (AIA) rat model by targeting VEGF and HIF-1{alpha}. BP-1 administered hypoxic endothelial cells and arthritic animals clearly showed down regulation of VEGF expression. Further, BP-1 inhibits nuclear translocation of HIF-1{alpha}, which in turn suppresses transcription of the VEGF gene. These results suggest a further possible clinical application of the BP-1 derivative as an anti-arthritic agent in association with conventional chemotherapeutic agents.

  14. Effect of hypoxia-inducible factor 1-alpha (HIF-1α) on proliferation ...

    African Journals Online (AJOL)

    Jane

    2011-07-25

    Jul 25, 2011 ... Full Length Research Paper. Effect of hypoxia-inducible factor 1-alpha ... 1Department of Neurosurgery, Ruijin Hospital, Shanghai JiaoTong University School of Medicine, Shanghai 200025,. China. 2Department of Neurosurgery, Chaoyang Hospital, Huainan, Anhui, China. 3Department of Neurosurgery ...

  15. Are Ichthyosporea animals or fungi? Bayesian phylogenetic analysis of elongation factor 1alpha of Ichthyophonus irregularis.

    Science.gov (United States)

    Ragan, Mark A; Murphy, Colleen A; Rand, Thomas G

    2003-12-01

    Ichthyosporea is a recently recognized group of morphologically simple eukaryotes, many of which cause disease in aquatic organisms. Ribosomal RNA sequence analyses place Ichthyosporea near the divergence of the animal and fungal lineages, but do not allow resolution of its exact phylogenetic position. Some of the best evidence for a specific grouping of animals and fungi (Opisthokonta) has come from elongation factor 1alpha, not only phylogenetic analysis of sequences but also the presence or absence of short insertions and deletions. We sequenced the EF-1alpha gene from the ichthyosporean parasite Ichthyophonus irregularis and determined its phylogenetic position using neighbor-joining, parsimony and Bayesian methods. We also sequenced EF-1alpha genes from four chytrids to provide broader representation within fungi. Sequence analyses and the presence of a characteristic 12 amino acid insertion strongly indicate that I. irregularis is a member of Opisthokonta, but do not resolve whether I. irregularis is a specific relative of animals or of fungi. However, the EF-1alpha of I. irregularis exhibits a two amino acid deletion heretofore reported only among fungi.

  16. Production of interleukin-1alpha by human endometrial stromal cells is triggered during menses and dysfunctional bleeding and is induced in culture by epithelial interleukin-1alpha released upon ovarian steroids withdrawal.

    Science.gov (United States)

    Pretto, Chrystel M; Gaide Chevronnay, Héloïse P; Cornet, Patricia B; Galant, Christine; Delvaux, Denis; Courtoy, Pierre J; Marbaix, Etienne; Henriet, Patrick

    2008-10-01

    Endometrial breakdown during menstruation and dysfunctional bleeding is triggered by the abrupt expression of matrix metalloproteinases (MMPs), including interstitial collagenase (MMP-1). The paracrine induction of MMP-1 in stromal cells via epithelium-derived IL-1alpha is repressed by ovarian steroids. However, the control by estradiol (E) and progesterone (P) of endometrial IL-1alpha expression and bioactivity remains unknown. Variations of endometrial IL-1alpha mRNA and protein along the menstrual cycle and during dysfunctional bleeding were determined using RT-PCR, in situ hybridization, and immunolabeling. The mechanism of EP control was analyzed using culture of explants, laser capture microdissection, and purified cells. Data were compared with expression changes of IL-1beta and IL-1 receptor antagonist. IL-1alpha is synthesized by epithelial cells throughout the cycle but E and/or P prevents its release. In contrast, endometrial stromal cells produce IL-1alpha only at menses and during irregular bleeding in areas of tissue breakdown. Stromal expression of IL-1alpha, like that of MMP-1, is repressed by P (alone or with E) but triggered by epithelium-derived IL-1alpha released upon EP withdrawal. Our experiments in cultured endometrium suggest that IL-1alpha released by epithelial cells triggers the production of IL-1alpha by stromal cells in a paracrine amplification loop to induce MMP-1 expression during menstruation and dysfunctional bleeding. All three steps of this amplification cascade are repressed by EP.

  17. 1alpha-hydroxylase and innate immune responses to 25-hydroxyvitamin D in colonic cell lines.

    Science.gov (United States)

    Lagishetty, Venu; Chun, Rene F; Liu, Nancy Q; Lisse, Thomas S; Adams, John S; Hewison, Martin

    2010-07-01

    Vitamin D-insufficiency is a prevalent condition in populations throughout the world, with low serum levels of 25-hydroxyvitamin D (25OHD) linked to a variety of human health concerns including cancer, autoimmune disease and infection. Current data suggest that 25OHD action involves localized extra-renal conversion to 1,25-dihydroxyvitamin D (1,25(OH)2D) via tissue-specific expression of the enzyme 25-hydroxyvitamin D-1alpha-hydroxylase (1alpha-hydroxylase). In cells such as macrophages, expression of 1alpha-hydroxylase is intimately associated with toll-like receptor (TLR) recognition of pathogens. However, this mechanism may not be exclusive to extra-renal generation of 1,25(OH)2D. To investigate the relationship between TLR-mediated pathogen recognition and vitamin D-induced antibacterial activity, intracrine responses to 25OHD metabolism were explored in vitro using the established colonic cell lines Caco-2 and Caco-2 clone BBe. Analysis of antibacterial factors such as cathelicidin (LL37) and beta-defensin-4 (DEFB4) was carried out following co-treatment with TLR ligands. Data indicate that, unlike macrophages, Caco-2 and BBe colonic cell lines are unresponsive to TLR-induced 1alpha-hydroxylase. Alternative activators of 1alpha-hydroxylase such as transforming growth factor beta were also ineffective at priming intracrine responses to 25OHD. Thus, in common with other barrier sites such as the skin or placenta, colonic epithelial cells may require specific factors to initiate intracrine responses to vitamin D. Copyright (c) 2010 Elsevier Ltd. All rights reserved.

  18. D-Glucosamine down-regulates HIF-1{alpha} through inhibition of protein translation in DU145 prostate cancer cells

    Energy Technology Data Exchange (ETDEWEB)

    Park, Jee-Young; Park, Jong-Wook; Suh, Seong-Il [Chronic Disease Research Center, School of Medicine, Keimyung University, 194 Dongsan-Dong, Jung-Gu, Daegu 700-712 (Korea, Republic of); Baek, Won-Ki, E-mail: wonki@dsmc.or.kr [Chronic Disease Research Center, School of Medicine, Keimyung University, 194 Dongsan-Dong, Jung-Gu, Daegu 700-712 (Korea, Republic of)

    2009-04-24

    D-Glucosamine has been reported to inhibit proliferation of cancer cells in culture and in vivo. In this study we report a novel response to D-glucosamine involving the translation regulation of hypoxia inducible factor (HIF)-1{alpha} expression. D-Glucosamine caused a decreased expression of HIF-1{alpha} under normoxic and hypoxic conditions without affecting HIF-1{alpha} mRNA expression in DU145 prostate cancer cells. D-Glucosamine inhibited HIF-1{alpha} accumulation induced by proteasome inhibitor MG132 and prolyl hydroxylase inhibitor DMOG suggesting D-glucosamine reduces HIF-1{alpha} protein expression through proteasome-independent pathway. Metabolic labeling assays indicated that D-glucosamine inhibits translation of HIF-1{alpha} protein. In addition, D-glucosamine inhibited HIF-1{alpha} expression induced by serum stimulation in parallel with inhibition of p70S6K suggesting D-glucosamine inhibits growth factor-induced HIF-1{alpha} expression, at least in part, through p70S6K inhibition. Taken together, these results suggest that D-glucosamine inhibits HIF-1{alpha} expression through inhibiting protein translation and provide new insight into a potential mechanism of the anticancer properties of D-glucosamine.

  19. Effect of higher muscle coactivation on standing postural response to perturbation in older adults.

    Science.gov (United States)

    Nagai, Koutatsu; Okita, Yusuke; Ogaya, Shinya; Tsuboyama, Tadao

    2017-04-01

    Although several studies have reported that muscle coactivation during postural control increases with age, the effect of higher muscle coactivation on standing postural response to perturbation is unknown. To investigate whether higher muscle coactivation affects standing postural response to perturbation in older adults. Thirty-four community-dwelling older participants were randomly assigned either to the coactivation group (CG), where muscle coactivation was increased intentionally, or to the non-coactivation group (NCG). The participants were instructed to stand on a force plate that moved forward or backward. Electromyography data were collected from the lower leg muscles. We requested the participants in the CG to increase the activity of their tibialis anterior, and to maintain this posture during the tasks. We moved the force plate with a constant amplitude and velocity, and measured kinematic data with a camera during the tasks. During forward transfer, the knee extension and hip flexion decreased in the CG after perturbation compared to NCG, and the trunk extension angle increased. The center of pressure (COP) displacement decreased around the peak of the movement in the CG compared to NCG. During backward transfer, ankle dorsal and knee flexion changed after perturbation in the CG compared to NCG. Our study found that higher muscle coactivation inhibits lower limb and COP movement as well as increases trunk tilt and the risk for falls during forward perturbations. Postural control with higher coactivation appears to be inefficient for maintaining balance during the backward sway of posture.

  20. Thermoluminescent coactivated rare earth oxyhalide phosphors and x-ray image converters utilizing said phosphors

    International Nuclear Information System (INIS)

    Rabatin, J.G.

    1984-01-01

    Oxyhalides of lanthanum, gadolinium and lutetium coactivated with a first activator selected from bismuth and samarium to provide the color of light emission and a second coactivator (e.g. terbium or praseodymium) which increases the amount of stored energy in a stored radiographic latent image are found to be superior in their conversion efficiency of x-rays to visible light. (author)

  1. Proline primed helix length as a modulator of the nuclear receptor-coactivator interaction

    NARCIS (Netherlands)

    Fuchs, S.; Nguyen, H.D.; Phan, T.T.T.; Burton, M.F.; Nieto, L.; Vries-van Leeuwen, I.J. de; Schmidt, A.; Goodarzifard, M.; Agten, S.M.; Rose, R.; Ottmann, C.; Milroy, L.G.; Brunsveld, L.

    2013-01-01

    Nuclear receptor binding to coactivator proteins is an obligate first step in the regulation of gene transcription. Nuclear receptors preferentially bind to an LXXLL peptide motif which is highly conserved throughout the 300 or so natural coactivator proteins. This knowledge has shaped current

  2. Flavonoids-induced accumulation of hypoxia-inducible factor (HIF)-1alpha/2alpha is mediated through chelation of iron.

    Science.gov (United States)

    Park, Sung-Soo; Bae, Insoo; Lee, Yong J

    2008-04-15

    Hypoxia-inducible factor-1 alpha (HIF-1alpha) is the regulatory subunit of the heterodimeric transcription factor HIF-1 that is the key regulator of cellular response to low oxygen tension. Under normoxic conditions, HIF-1alpha is continuously degraded by the ubiquitin-proteasome pathway through pVHL (von Hippel-Lindau tumor suppressor protein). Under hypoxic conditions, HIF-1alpha is stabilized and induces the transcription of HIF-1 target genes. Quercetin, a flavonoid with anti-oxidant, anti-inflammatory, and kinase modulating properties, has been found to induce HIF-1alpha accumulation and VEGF secretion in normoxia. In this study, the molecular mechanisms of quercetin-mediated HIF-1alpha accumulation were investigated. Previous studies have shown that, in addition to being induced by hypoxia, HIF-1alpha can be induced through the phosphatidylinositol 3-kinase (PI3K)/Akt and p53 signaling pathways. But our study revealed, through p53 mutant-type as well as p53 null cell lines, that neither the PI3K/Akt nor the p53 signaling pathway is required for quercetin-induced HIF-1alpha accumulation. And we observed that HIF-1alpha accumulated by quercetin is not ubiquitinated and the interaction of HIF-1alpha with pVHL is reduced, compared with HIF-1alpha accumulated by the proteasome inhibitor MG132. The use of quercetin's analogues showed that only quercetin and galangin induce HIF-1/2alpha accumulation and this effect is completely reversed by additional iron ions. This is because quercetin and galangin are able to chelate cellular iron ions that are cofactors of HIF-1/2alpha proline hydroxylase (PHD). These data suggest that quercetin inhibits the ubiquitination of HIF-1/2alpha in normoxia by hindering PHD through chelating iron ions.

  3. Co-activation: its association with weakness and specific neurological pathology

    Directory of Open Access Journals (Sweden)

    Wiles Charles M

    2006-11-01

    Full Text Available Abstract Background Net agonist muscle strength is in part determined by the degree of antagonist co-activation. The level of co-activation might vary in different neurological disorders causing weakness or might vary with agonist strength. Aim This study investigated whether antagonist co-activation changed a with the degree of muscle weakness and b with the nature of the neurological lesion causing weakness. Methods Measures of isometric quadriceps and hamstrings strength were obtained. Antagonist (hamstring co-activation during knee extension was calculated as a ratio of hamstrings over quadriceps activity both during an isometric and during a functional sit to stand (STS task (using kinematics in groups of patients with extrapyramidal (n = 15, upper motor neuron (UMN (n = 12, lower motor neuron (LMN with (n = 18 or without (n = 12 sensory loss, primary muscle or neuromuscular junction disorder (n = 17 and in healthy matched controls (n = 32. Independent t-tests or Mann Witney U tests were used to compare between the groups. Correlations between variables were also investigated. Results In healthy subjects mean (SD co-activation of hamstrings during isometric knee extension was 11.8 (6.2% and during STS was 20.5 (12.9%. In patients, co-activation ranged from 7 to 17% during isometric knee extension and 15 to 25% during STS. Only the extrapyramidal group had lower co-activation levels than healthy matched controls (p Conclusion It is concluded that antagonist co-activation does not systematically vary with the site of neurological pathology when compared to healthy matched controls or, in most patient groups, with strength. The lower co-activation levels found in the extrapyramidal group require confirmation and further investigation. Co-activation may be relevant to individuals with muscle weakness. Within patient serial studies in the presence of changing muscle strength may help to understand these relationships more clearly.

  4. Radioprotection of the intestinal crypts of mice by recombinant human interleukin-1 alpha

    International Nuclear Information System (INIS)

    Wu, S.G.; Miyamoto, T.

    1990-01-01

    Recombinant human interleukin-1 alpha (rHIL-1 alpha or IL-1) protected the intestinal crypt cells of mice against X-ray-induced damage. The survival of crypt cells measured in terms of their ability to form colonies of regenerating duodenal epithelium in situ was increased when IL-1 was given either before or after irradiation. The maximum degree of radioprotection was seen when the drug was given between 13 and 25 h before irradiation. The IL-1 dose producing maximum protection was about 6.3 micrograms/kg. This is the first report indicating that the cytokine IL-1 has a radioprotective effect in the intestine. The finding suggests that IL-1 may be of potential value in preventing radiation injury to the gut in the clinic

  5. Partial deficiency of HIF-1 alpha stimulates pathological cardiac changes in streptozotocin-induced diabetic mice

    Czech Academy of Sciences Publication Activity Database

    Bohuslavová, Romana; Kolář, František; Sedmera, David; Škvorová, Lada; Papoušek, František; Neckář, Jan; Pavlínková, Gabriela

    2014-01-01

    Roč. 14, Feb 6 (2014) ISSN 1472-6823 R&D Projects: GA ČR GA301/09/0117; GA MŠk(CZ) ED1.1.00/02.0109 Institutional research plan: CEZ:AV0Z50520701 Institutional support: RVO:68378271 Keywords : Echocardiographic parameters * Hypoxia inducible factor 1 alpha * Diabetic cardiomyopathy Subject RIV: FB - Endocrinology, Diabetology, Metabolism, Nutrition Impact factor: 1.710, year: 2014

  6. HIF-1alpha Deficiency Attenuates the Cardiomyogenesis of Mouse Embryonic Stem Cells

    Czech Academy of Sciences Publication Activity Database

    Kudová, Jana; Procházková, J.; Vašíček, Ondřej; Perečko, Tomáš; Sedláčková, M.; Pešl, M.; Pachernik, J.; Kubala, Lukáš

    2016-01-01

    Roč. 11, č. 6 (2016) E-ISSN 1932-6203 R&D Projects: GA ČR GA13-29358S Grant - others:Grantová agentura ČR - GA ČR(CZ) GJ15-13443Y Institutional support: RVO:68081707 Keywords : INDUCIBLE FACTOR 1- ALPHA * GENE-EXPRESSION * CARDIAC DIFFERENTIATION Subject RIV: BO - Biophysics Impact factor: 2.806, year: 2016

  7. Effect of intravenous 1-alpha-hydroxyvitamin D3 on secondary hyperparathyroidism in chronic uremic patients on maintenance hemodialysis

    DEFF Research Database (Denmark)

    Brandi, L; Daugaard, H; Tvedegaard, E

    1989-01-01

    The effect of intravenous 1 alpha(OH)D3 on circulating intact parathyroid hormone (PTH) and COOH-terminal immunoreactive PTH was examined in 21 patients on chronic hemodialysis. The patients were treated for 3 months with increasing doses of 1 alpha(OH)D3 under careful control of serum Ca2+. 1 al...

  8. Expression of hypoxia-induced factor-1 alpha in early-stage and in metastatic oral squamous cell carcinoma.

    Science.gov (United States)

    Ribeiro, Maisa; Teixeira, Sarah R; Azevedo, Monarko N; Fraga, Ailton C; Gontijo, Antônio Pm; Vêncio, Eneida F

    2017-04-01

    To investigate hypoxia-induced factor-1 alpha expression in distinct oral squamous cell carcinoma subtypes and topographies and correlate with clinicopathological data. Hypoxia-induced factor-1 alpha expression was assessed by immunohistochemistry in 93 cases of OSCC. Clinical and histopathological data were reviewed from medical records. Hypoxia-induced factor-1 alpha status was distinct according to tumor location, subtype and topography affect. In superficial oral squamous cell carcinomas, most tumor cells overexpressed hypoxia-induced factor-1 alpha, whereas hypoxia-induced factor-1 alpha was restricted to the intratumoral region in conventional squamous cell carcinomas. All basaloid squamous cell carcinomas exhibited downregulation of hypoxia-induced factor-1 alpha. Interestingly, metastatic lymph nodes (91.7%, p = 0.001) and the intratumoral regions of corresponding primary tumors (58.3%, p = 0.142) showed hypoxia-induced factor-1 alpha-positive tumor cells. Overall survival was poor in patients with metastatic lymph nodes. Hypoxia-induced factor-1 alpha has distinct expression patterns in different oral squamous cell carcinoma subtypes and topographies, suggesting that low oxygen tension promotes the growth pattern of superficial and conventional squamous cell carcinoma, but not basaloid squamous cell carcinoma. Indeed, a hypoxic environment may facilitate regional metastasis, making it a useful diagnostic and prognostic marker in primary tumors.

  9. Long-term suppression of secondary hyperparathyroidism by intravenous 1 alpha-hydroxyvitamin D3 in patients on chronic hemodialysis

    DEFF Research Database (Denmark)

    Brandi, L; Daugaard, H; Tvedegaard, E

    1992-01-01

    The effect of intravenous 1 alpha-hydroxyvitamin D3 [1 alpha(OH)D3] on circulating levels of intact parathyroid hormone (PTH 1-84) and COOH-terminal immunoreactive PTH(PTH 53-84) was examined in 13 patients on chronic hemodialysis. Thirteen patients were treated for 300 days (10 months), 9 patien...

  10. The Structure of Neurexin 1[alpha] Reveals Features Promoting a Role as Synaptic Organizer

    Energy Technology Data Exchange (ETDEWEB)

    Chen, Fang; Venugopal, Vandavasi; Murray, Beverly; Rudenko, Gabby (Michigan)

    2014-10-02

    {alpha}-Neurexins are essential synaptic adhesion molecules implicated in autism spectrum disorder and schizophrenia. The {alpha}-neurexin extracellular domain consists of six LNS domains interspersed by three EGF-like repeats and interacts with many different proteins in the synaptic cleft. To understand how {alpha}-neurexins might function as synaptic organizers, we solved the structure of the neurexin 1{alpha} extracellular domain (n1{alpha}) to 2.65 {angstrom}. The L-shaped molecule can be divided into a flexible repeat I (LNS1-EGF-A-LNS2), a rigid horseshoe-shaped repeat II (LNS3-EGF-B-LNS4) with structural similarity to so-called reelin repeats, and an extended repeat III (LNS5-EGF-B-LNS6) with controlled flexibility. A 2.95 {angstrom} structure of n1{alpha} carrying splice insert SS3 in LNS4 reveals that SS3 protrudes as a loop and does not alter the rigid arrangement of repeat II. The global architecture imposed by conserved structural features enables {alpha}-neurexins to recruit and organize proteins in distinct and variable ways, influenced by splicing, thereby promoting synaptic function.

  11. Endurance exercise induces mRNA expression of oxidative enzymes in human skeletal muscle late in recovery

    DEFF Research Database (Denmark)

    Leick, Lotte; Plomgaard, Peter S.; Grønløkke, L.

    2010-01-01

    exercise. To test the hypothesis that mRNA expression of many oxidative enzymes is up-regulated late in recovery (10-24 h) after exercise, male subjects (n=8) performed a 90-min cycling exercise (70% VO(2-max)), with muscle biopsies obtained before exercise (pre), and after 10, 18 and 24 h of recovery....... The mRNA expression of carnitine-palmitoyltransferase (CPT)I, CD36, 3-hydroxyacyl-CoA-dehydrogenase (HAD), cytochrome (Cyt)c, aminolevulinate-delta-synthase (ALAS)1 and GLUT4 was 100-200% higher at 10-24 h of recovery from exercise than in a control trial. Exercise induced a 100-300% increase...... in peroxisome proliferator-activated receptor gamma co-activator (PGC)-1alpha, citrate synthase (CS), CPTI, CD36, HAD and ALAS1 mRNA contents at 10-24 h of recovery relative to before exercise. No protein changes were detected in Cytc, ALAS1 or GLUT4. This shows that mRNA expression of several training...

  12. The association between antagonist hamstring coactivation and episodes of knee joint shifting and buckling.

    Science.gov (United States)

    Segal, N A; Nevitt, M C; Welborn, R D; Nguyen, U-S D T; Niu, J; Lewis, C E; Felson, D T; Frey-Law, L

    2015-07-01

    Hamstring coactivation during quadriceps activation is necessary to counteract the quadriceps pull on the tibia, but coactivation can be elevated with symptomatic knee osteoarthritis (OA). To guide rehabilitation to attenuate risk for mobility limitations and falls, this study evaluated whether higher antagonistic open kinetic chain hamstring coactivation is associated with knee joint buckling (sudden loss of support) and shifting (a sensation that the knee might give way). At baseline, median hamstring coactivation was assessed during maximal isokinetic knee extensor strength testing and at baseline and 24-month follow-up, knee buckling and shifting was self-reported. Associations between tertiles of co-activation and knee (1) buckling, (2) shifting and (3) either buckling or shifting were assessed using logistic regression, adjusted for age, sex, knee OA and pain. 1826 participants (1089 women) were included. Mean ± SD age was 61.7 ± 7.7 years, BMI was 30.3 ± 5.5 kg/m(2) and 38.2% of knees had OA. There were no consistent statistically significant associations between hamstring coactivation and ipsilateral prevalent or incident buckling or the combination of buckling and shifting. The odds ratios for incident shifting in the highest in comparison with the lowest tertile of coactivation had similar magnitudes in the combined and medial hamstrings, but only reached statistical significance for lateral hamstring coactivation, OR(95%CI) 1.53 (0.99, 2.36). Hamstring coactivation during an open kinetic chain quadriceps exercise was not consistently associated with prevalent or incident self-reported knee buckling or shifting in older adults with or at risk for knee OA. Copyright © 2015. Published by Elsevier Ltd.

  13. Retinal neuroprotection by hypoxic preconditioning is independent of hypoxia-inducible factor-1 alpha expression in photoreceptors.

    Science.gov (United States)

    Thiersch, Markus; Lange, Christina; Joly, Sandrine; Heynen, Severin; Le, Yun Zheng; Samardzija, Marijana; Grimm, Christian

    2009-06-01

    Hypoxic preconditioning stabilizes hypoxia-inducible factor (HIF) 1 alpha in the retina and protects photoreceptors against light-induced cell death. HIF-1 alpha is one of the major transcription factors responding to low oxygen tension and can differentially regulate a large number of target genes. To analyse whether photoreceptor-specific expression of HIF-1 alpha is essential to protect photoreceptors by hypoxic preconditioning, we knocked down expression of HIF-1 alpha specifically in photoreceptor cells, using the cyclization recombinase (Cre)-lox system. The Cre-mediated knockdown caused a 20-fold reduced expression of Hif-1 alpha in the photoreceptor cell layer. In the total retina, RNA expression was reduced by 65%, and hypoxic preconditioning led to only a small increase in HIF-1 alpha protein levels. Accordingly, HIF-1 target gene expression after hypoxia was significantly diminished. Retinas of Hif-1 alpha knockdown animals did not show any pathological alterations, and tolerated hypoxic exposure in a comparable way to wild-type retinas. Importantly, the strong neuroprotective effect of hypoxic preconditioning against light-induced photoreceptor degeneration persisted in knockdown mice, suggesting that hypoxia-mediated survival of light exposure does not depend on an autocrine action of HIF-1 alpha in photoreceptor cells. Hypoxia-mediated stabilization of HIF-2 alpha and phosphorylation of signal transducer and activator of transcription 3 (STAT 3) were not affected in the retinas of Hif-1 alpha knockdown mice. Thus, these factors are candidates for regulating the resistance of photoreceptors to light damage after hypoxic preconditioning, along with several potentially neuroprotective genes that were similarly induced in hypoxic knockdown and control mice.

  14. Hypoxia inducible factor 1-alpha (HIF-1 alpha is induced during reperfusion after renal ischemia and is critical for proximal tubule cell survival.

    Directory of Open Access Journals (Sweden)

    Elisa Conde

    Full Text Available Acute tubular necrosis (ATN caused by ischemia/reperfusion (I/R during renal transplantation delays allograft function. Identification of factors that mediate protection and/or epithelium recovery could help to improve graft outcome. We studied the expression, regulation and role of hypoxia inducible factor 1-alpha (HIF-1 α, using in vitro and in vivo experimental models of I/R as well as human post-transplant renal biopsies. We found that HIF-1 α is stabilized in proximal tubule cells during ischemia and unexpectedly in late reperfusion, when oxygen tension is normal. Both inductions lead to gene expression in vitro and in vivo. In vitro interference of HIF-1 α promoted cell death and in vivo interference exacerbated tissue damage and renal dysfunction. In pos-transplant human biopsies, HIF-1 α was expressed only in proximal tubules which exhibited normal renal structure with a significant negative correlation with ATN grade. In summary, using experimental models and human biopsies, we identified a novel HIF-1 α induction during reperfusion with a potential critical role in renal transplant.

  15. Targeted deficiency of the transcriptional activator Hnf1alpha alters subnuclear positioning of its genomic targets.

    Directory of Open Access Journals (Sweden)

    Reini F Luco

    2008-05-01

    Full Text Available DNA binding transcriptional activators play a central role in gene-selective regulation. In part, this is mediated by targeting local covalent modifications of histone tails. Transcriptional regulation has also been associated with the positioning of genes within the nucleus. We have now examined the role of a transcriptional activator in regulating the positioning of target genes. This was carried out with primary beta-cells and hepatocytes freshly isolated from mice lacking Hnf1alpha, an activator encoded by the most frequently mutated gene in human monogenic diabetes (MODY3. We show that in Hnf1a-/- cells inactive endogenous Hnf1alpha-target genes exhibit increased trimethylated histone H3-Lys27 and reduced methylated H3-Lys4. Inactive Hnf1alpha-targets in Hnf1a-/- cells are also preferentially located in peripheral subnuclear domains enriched in trimethylated H3-Lys27, whereas active targets in wild-type cells are positioned in more central domains enriched in methylated H3-Lys4 and RNA polymerase II. We demonstrate that this differential positioning involves the decondensation of target chromatin, and show that it is spatially restricted rather than a reflection of non-specific changes in the nuclear organization of Hnf1a-deficient cells. This study, therefore, provides genetic evidence that a single transcriptional activator can influence the subnuclear location of its endogenous genomic targets in primary cells, and links activator-dependent changes in local chromatin structure to the spatial organization of the genome. We have also revealed a defect in subnuclear gene positioning in a model of a human transcription factor disease.

  16. [Rat cardiomyocyte remodeling after neonatal cryptosporidiosis. II. Elongation, excessive polyploidization and HIF-1alpha overexpression].

    Science.gov (United States)

    Anatskaia, O V; Sidorenko, N V; Matveev, I V; Kropotov, A V; Vinogradov, A E

    2012-01-01

    Retrospective epidemyological studies evidence that infant diseases leave survivors with an increased susceptibility to cardiovascular diseases in later life. At the same time, the mechanisms of this link remain poorly understood. Based on medical statistics reporting that infectious gastroenteritis is the most common cause of maladies in babies, infants and children, we analysed the effects of moderate cryptosporidial gastroenteritis on the heart and ventricular cardiomyocyte remodelling in rats of the first month of life. The disease was challenged by a worldwide human protozoic pathogen Cryptosporidium parvum (Apicomplexa, Sporozoa). The main symptoms manifested in the growth retardation moderate diarrhea. Using real-time PCR, cytophotometry, confocal microscopy and image analysis, we indicated that cryptosporidiosis was associated, with the atrophy heart and the elongation, narrowing, protein content decrease and hyperpolyploidization of cardiomyocytes and the moderate overexpression of hypoxia inducible factor 1alpha (HIF-1alpha) mRNA. Cardiomyocyte shape remodeling and heart atrophy presented in all age groups. The severity of these changes, hovewer, declined gradually from younger to older groups. In contrast, hyperpolyploidization and HIF-1alpha mRNA overexpression were registered mainly among animals aged between 6 and 13 days, and were barely detected and non-significant in older age groups. In the rat the time period covering 6-13 days after birth is known to coincide with the intensive cardiomyocyte polyploidization and the switch from proliferation to hypertrophy. Thus, our data indicate that neonatal cryptosporidiosis may be potential cardiovascular diseases risk factor and that one of the critical time windows for the growing heart covers the time period when cardiomyocyte undergo polyploidization.

  17. Intermittent intravenous followed by intermittent oral 1 alpha(OH)D3 treatment of secondary hyperparathyroidism in uraemia

    DEFF Research Database (Denmark)

    Brandi, L; Daugaard, H; Egsmose, C

    1996-01-01

    OBJECTIVES: To examine whether intermittent oral 1 alpha(OH)D3 treatment of patients on haemodialysis with secondary hyperparathyroidism (HPT) was able to maintain the marked suppression of PTH, which previously had been induced by an intermittent intravenous administration of 1 alpha(OH)D3....... Simultaneously, the effect of the different routes of administration of 1 alpha(OH)D3 on the circulating levels of N- and C-terminal PTH fragments was measured. DESIGN: An open study of patients on chronic haemodialysis. SETTING: Renal division, Rigshospitalet, Copenhagen, Denmark. SUBJECTS: A total of 26...

  18. Regulation of eukaryotic elongation factor 1 alpha (eEF1A) by dynamic lysine methylation

    DEFF Research Database (Denmark)

    Jakobsson, Magnus E; Małecki, Jędrzej; Falnes, Pål Ø

    2018-01-01

    Lysine methylation is a frequent post-translational protein modification, which has been intensively studied in the case of histone proteins. Lysine methylations are also found on many non-histone proteins, and one prominent example is eukaryotic elongation factor 1 alpha (eEF1A). Besides its...... essential role in the protein synthesis machinery, a number of non-canonical functions have also been described for eEF1A, such as regulation of the actin cytoskeleton and the promotion of viral replication. The functional significance of the extensive lysine methylations on eEF1A, as well as the identity...

  19. Enhancing the smoothness of joint motion induced by functional electrical stimulation using co-activation strategies

    Directory of Open Access Journals (Sweden)

    Ruppel Mirjana

    2017-09-01

    Full Text Available The motor precision of today’s neuroprosthetic devices that use artificial generation of limb motion using Functional Electrical Stimulation (FES is generally low. We investigate the adoption of natural co-activation strategies as present in antagonistic muscle pairs aiming to improve motor precision produced by FES. In a test in which artificial knee-joint movements were generated, we could improve the smoothness of FES-induced motion by 513% when applying co-activation during the phases in which torque production is switched between muscles – compared to no co-activation. We further demonstrated how the co-activation level influences the joint stiffness in a pendulum test.

  20. [Effects of intermittent hypoxic exposure on the parameter of erythrocyte and serum hypoxia inducible factor-1 alpha and erythropoietin levels].

    Science.gov (United States)

    Zhang, Cheng-yan; Zhang, Ji-xin; Lü, Xiao-tao; Li, Bao-yu

    2009-10-01

    To investigate the effects of intermittent hypoxic exposure and normoxic convalescence on the parameter of erythrocyte and serum hypoxia inducible factor-1 alpha (HIF-1alpha) and erythropoietin (EPO) levels. Rat models of intermittent hypoxic exposure were established, combined with the clinical research on volunteers experiencing the intermittent plateau work. Blood samples for red blood cell (RBC) counts, hemoglobin (Hb) and hematocrit (HCT) were collected, serum HIF-1alpha and EPO levels were measured using enzyme linked immunosorbent assay. RBC counts, Hb concentration and HCT were significantly higher than the normoxic group (P hypoxic exposure can enhance serum hypoxia inducible factor-1 alpha and erythropointin levels and the generation of red blood cells, which leads to an increase in hemoglobin concentration and hematocrit. The results have changed with the hypoxic exposure period prolonged. Normoxic convalescence after intermittent hypoxic exposure can make the related indexes reduced, and contribute to the organism recovery.

  1. Serum concentrations of interleukin-1 alpha, interleukin-6 and tumor necrosis factor-alpha in neonatal sepsis and meningitis

    International Nuclear Information System (INIS)

    Fida, Nadia M.; Fadelallah, Mohamed F.; Al-Mughales, Jamil A.

    2006-01-01

    To investigate whether serum levels of interleukin-1alpha (IL-1alpha), IL-6, tumor necrosis factor alpha (TNF-alpha), C-reactive protein (CRP) are useful in the diagnosis of neonatal sepsis and meningitis and differentiate them. Blood samples were collected from 35 full term neonates with suspected infection who admitted to the Neonatology Unit, Pediatric Department, King Abdul-Aziz University Hospital, Jeddah, Saudi Arabia during January 2002 - June 2003. On the basis of laboratory and bacteriological results, newborns were classified into: sepsis (n=28), meningitis (n=7), and healthy controls (n=16). Sepsis groups were further subdivided according to culture results into: group 1 = proven sepsis (n=6), group 2 = clinical sepsis (n=14), and group 3 = possible-infected (n=8). Serum levels of IL-1alpha, IL-6, TNF-alpha were measured using Enzyme-Linked Immunosorbent Assay while CRP by nephelometer: In sepsis and meningitis patients, serum levels of CRP (p<0.01, p<0.05,) and IL-1alpha (p<0.001, p<0.05) were elevated than controls. C-reactive protein levels elevated in proven sepsis (p<0.001) and IL-1alpha elevated in all subgroups of sepsis (groups 1, 2, 3) compared with (p<0.05, p<0.001, p<0.01) controls. Interleukin-6, TNF-alpha showed no significant differences between studied groups. In sepsis and meningitis, IL-1alpha had a highest sensitivity (89%, 86%), and negative predictive values (89% and 93%). Interleukin-1alpha and CRP increased in neonatal sepsis and meningitis, but cannot differentiate between them. Interleukin-1alpha had a highest sensitivity in prediction of neonatal infection and its assessment may improve accuracy of diagnosis. (author)

  2. Increased lower limb muscle coactivation reduces gait performance and increases metabolic cost in patients with hereditary spastic paraparesis.

    Science.gov (United States)

    Rinaldi, Martina; Ranavolo, Alberto; Conforto, Silvia; Martino, Giovanni; Draicchio, Francesco; Conte, Carmela; Varrecchia, Tiwana; Bini, Fabiano; Casali, Carlo; Pierelli, Francesco; Serrao, Mariano

    2017-10-01

    The aim of this study was to investigate the lower limb muscle coactivation and its relationship with muscles spasticity, gait performance, and metabolic cost in patients with hereditary spastic paraparesis. Kinematic, kinetic, electromyographic and energetic parameters of 23 patients and 23 controls were evaluated by computerized gait analysis system. We computed ankle and knee antagonist muscle coactivation indexes throughout the gait cycle and during the subphases of gait. Energy consumption and energy recovery were measured as well. In addition to the correlation analysis between coactivation indexes and clinical variables, correlations between coactivation indexes and time-distance, kinematic, kinetic, and energetic parameters were estimated. Increased coactivity indexes of both knee and ankle muscles throughout the gait cycle and during the subphases of gait were observed in patients compared with controls. Energetic parameters were significantly higher in patients than in controls. Both knee and ankle muscle coactivation indexes were positively correlated with knee and ankle spasticity (Ashworth score), respectively. Knee and ankle muscle coactivation indexes were both positively correlated with energy consumption and both negatively correlated with energy recovery. Positive correlations between the Ashworth score and lower limb muscle coactivation suggest that abnormal lower limb muscle coactivation in patients with hereditary spastic paraparesis reflects a primary deficit linked to lower limb spasticity. Furthermore, these abnormalities influence the energetic mechanisms during walking. Identifying excessive muscle coactivation may be helpful in individuating the rehabilitative treatments and designing specific orthosis to restrain spasticity. Copyright © 2017 Elsevier Ltd. All rights reserved.

  3. A novel role for the cell cycle regulatory complex cyclin D1-CDK4 in gluconeogenesis

    OpenAIRE

    Hosooka, Tetsuya; Ogawa, Wataru

    2016-01-01

    Dysregulation of gluconeogenesis is a key pathological feature of type 2 diabetes. However, the molecular mechanisms underlying the regulation of gluconeogenesis remain unclear. Bhalla et?al. recently reported that cyclin D1 suppresses hepatic gluconeogenesis through CDK4?dependent phosphorylation of PGC1alpha and consequent inhibition of its activity. The cyclin D1?CDK4 might thus serve as an important link between the cell cycle and control of energy metabolism through modulation of PGC1alp...

  4. Involvement of fractalkine and macrophage inflammatory protein-1 alpha in moderate-severe depression

    Directory of Open Access Journals (Sweden)

    Rosaria Alba Merendino

    2004-01-01

    Full Text Available MODERATE-severe depression (MSD is linked to overexpression of proinflammatory cytokines and chemokines. Fractalkine (FKN and macrophage inflammatory protein-1 alpha (MIP-1α are, respectively, members of CX3C and C-C chemokines, and both are involved in recruiting and activating mononuclear phagocytes in the central nervous system. We analysed the presence of FKN and MIP-1α in sera of untreated MSD patients and healthy donors. High FKN levels were observed in all MSD patients as compared with values only detectable in 26% of healthy donors. MIP-1α was measurable in 20% of patients, while no healthy donors showed detectable chemokine levels. In conclusion, we describe a previously unknown involvement of FKN in the pathogenesis of MSD, suggesting that FKN may represent a target for a specific immune therapy of this disease.

  5. Effect of Knee Joint Angle and Contraction Intensity on Hamstrings Coactivation.

    Science.gov (United States)

    Wu, Rui; Delahunt, Eamonn; Ditroilo, Massimiliano; Lowery, Madeleine M; DE Vito, Giuseppe

    2017-08-01

    This study investigated the effect of knee joint angle and contraction intensity on the coactivation of the hamstring muscles (when acting as antagonists to the quadriceps) in young and older individuals of both sexes. A total of 25 young (24 ± 2.6 yr) and 26 older (70 ± 2.5 yr) healthy men and women participated. Maximal voluntary isometric contraction of the knee extensors and flexors was assessed at two knee joint angles (90° and 60°, 0° = full extension). At each angle, participants performed submaximal contractions of the knee extensors (20%, 50%, and 80% maximal voluntary isometric contraction), whereas surface EMG was simultaneously acquired from the vastus lateralis and biceps femoris muscles to assess the level (EMG root-mean-square) of agonist activation and antagonist coactivation. Subcutaneous adipose tissue in the areas corresponding to surface EMG electrode placements was measured via ultrasonography. The contractions performed at 90° knee flexion demonstrated higher levels of antagonist coactivation (all P < 0.01) and agonist activation (all P < 0.01) as a function of contraction intensity compared with the 60° knee flexion. Furthermore, after controlling for subcutaneous adipose tissue, older participants exhibited a higher level of antagonist coactivation at 60° knee flexion compared with young participants (P < 0.05). The results of the present study suggest that 1) the antagonist coactivation is dependent on knee joint angle and contraction intensity and 2) subcutaneous adipose tissue may affect the measured coactivation level likely because of a cross-talk effect. Antagonist coactivation may play a protective role in stabilizing the knee joint and maintaining constant motor output.

  6. Incremental change in the set of coactive cortical assemblies enables mental continuity.

    Science.gov (United States)

    Reser, Jared Edward

    2016-12-01

    This opinion article explores how sustained neural firing in association areas allows high-order mental representations to be coactivated over multiple perception-action cycles, permitting sequential mental states to share overlapping content and thus be recursively interrelated. The term "state-spanning coactivity" (SSC) is introduced to refer to neural nodes that remain coactive as a group over a given period of time. SSC ensures that contextual groupings of goal or motor-relevant representations will demonstrate continuous activity over a delay period. It also allows potentially related representations to accumulate and coactivate despite delays between their initial appearances. The nodes that demonstrate SSC are a subset of the active representations from the previous state, and can act as referents to which newly introduced representations of succeeding states relate. Coactive nodes pool their spreading activity, converging on and activating new nodes, adding these to the remaining nodes from the previous state. Thus, the overall distribution of coactive nodes in cortical networks evolves gradually during contextual updating. The term "incremental change in state-spanning coactivity" (icSSC) is introduced to refer to this gradual evolution. Because a number of associated representations can be sustained continuously, each brain state is embedded recursively in the previous state, amounting to an iterative process that can implement learned algorithms to progress toward a complex result. The longer representations are sustained, the more successive mental states can share related content, exhibit progressive qualities, implement complex algorithms, and carry thematic or narrative continuity. Included is a discussion of the implications that SSC and icSSC may have for understanding working memory, defining consciousness, and constructing AI architectures. Copyright © 2016 The Author. Published by Elsevier Inc. All rights reserved.

  7. The effect of dietary protein restriction on the secretory dynamics of 1 alpha-hydroxycorticosterone and urea in the dogfish, Scyliorhinus canicula: a possible role for 1 alpha-hydroxycorticosterone in sodium retention.

    Science.gov (United States)

    Armour, K J; O'Toole, L B; Hazon, N

    1993-08-01

    The putative osmoregulatory role of the unique elasmobranch corticosteroid, 1 alpha-hydroxycorticosterone (1 alpha-OH-B), was investigated using dietary protein restriction as a means of limiting urea biosynthetic ability. Groups of dogfish (Scyliorhinus canicula) were adapted to either a high or a low protein diet (HPD and LPD respectively) and the secretory dynamics of urea and 1 alpha-OH-B were determined following acclimation to normal (100%), 130% and 50% sea water. In normal sea water, LPD fish showed significantly decreased blood production of urea compared with fish fed a HPD (P strategy adopted by these animals was the retention of high plasma concentrations of Na+ and Cl-, which increased plasma osmolality and tended to decrease osmotic water loss. Concomitant with the increased ion concentrations, plasma 1 alpha-OH-B concentration was also greatly elevated in LPD fish indicating that the steroid may be acting to minimize Na+ (and Cl-) excretion at osmoregulatory sites such as the rectal gland, kidney and gills. This and a previous study have also demonstrated that 1 alpha-OH-B concentration is elevated in 50% sea water. Decreases in plasma Na+ concentration are tolerated down to 75% sea water, whereafter Na+ is preferentially retained and further decreases in osmolality are achieved by reductions in plasma urea concentration.(ABSTRACT TRUNCATED AT 250 WORDS)

  8. Downstream signaling mechanism of the C-terminal activation domain of transcriptional coactivator CoCoA

    OpenAIRE

    Kim, Jeong Hoon; Yang, Catherine K.; Stallcup, Michael R.

    2006-01-01

    The coiled-coil coactivator (CoCoA) is a transcriptional coactivator for nuclear receptors and enhances nuclear receptor function by the interaction with the bHLH-PAS domain (AD3) of p160 coactivators. The C-terminal activation domain (AD) of CoCoA possesses strong transactivation activity and is required for the coactivator function of CoCoA with nuclear receptors. To understand how CoCoA AD transmits its activating signal to the transcription machinery, we defined specific subregions, amino...

  9. Taraxacum officinale induces cytotoxicity through TNF-alpha and IL-1alpha secretion in Hep G2 cells.

    Science.gov (United States)

    Koo, Hyun-Na; Hong, Seung-Heon; Song, Bong-Keun; Kim, Cheorl-Ho; Yoo, Young-Hyun; Kim, Hyung-Min

    2004-01-16

    Taraxacum officinale (TO) has been frequently used as a remedy for women's disease (e.g. breast and uterus cancer) and disorders of the liver and gallbladder. Several earlier studies have indicated that TO exhibits anti-tumor properties, but its mechanism remains to be elucidated. In this study, we investigated the effect of TO on the cytotoxicity and production of cytokines in human hepatoma cell line, Hep G2. Our results show that TO decreased the cell viability by 26%, and significantly increased the tumor necrosis factor (TNF)-alpha and interleukin (IL)-1alpha production compared with media control (about 1.6-fold for TNF-alpha, and 2.4-fold for IL-1alpha, P < 0.05). Also, TO strongly induced apoptosis of Hep G2 cells as determined by flow cytometry. Increased amounts of TNF-alpha and IL-1alpha contributed to TO-induced apoptosis. Anti-TNF-alpha and IL-1alpha antibodies almost abolished it. These results suggest that TO induces cytotoxicity through TNF-alpha and IL-1alpha secretion in Hep G2 cells.

  10. Signatures of memory: brain coactivations during retrieval distinguish correct from incorrect recollection

    Directory of Open Access Journals (Sweden)

    Avi Mendelsohn

    2010-04-01

    Full Text Available Are specific distributed coactivations in the brain during memory retrieval a signature of retrieval outcome? Here we show that this is indeed the case. Widespread brain networks were reported to be involved in the retrieval of long-term episodic memories. Although functional coactivation among particular regions occurs during episodic memory retrieval, it is unknown to what extent it contributes to the accuracy and confidence of recollection. In this study we set out to explore this question. Participants saw a narrative documentary movie. A week later they underwent an fMRI scan during which they either accepted or rejected factual or fictitious verbal statements concerning the movie. Correct vs. incorrect responses to factual statements were more common and were provided with higher confidence than those made to fictitious statements. Whereas activity in the retrieval network correlated mostly with confidence, coactivations primarily correlated with memory accuracy. Specifically, coactivations of left medial temporal lobe regions with temporal and parietal cortices were greater during correct responses to factual statements, but did not differ between responses to fictitious statements. We propose that network coactivations play a role in recovering memory traces that are relevant to online retrieval cues, culminating in distinct retrieval outcomes.

  11. FTZ-Factor1 and Fushi tarazu interact via conserved nuclear receptor and coactivator motifs

    Science.gov (United States)

    Schwartz, Carol J.E.; Sampson, Heidi M.; Hlousek, Daniela; Percival-Smith, Anthony; Copeland, John W.R.; Simmonds, Andrew J.; Krause, Henry M.

    2001-01-01

    To activate transcription, most nuclear receptor proteins require coactivators that bind to their ligand-binding domains (LBDs). The Drosophila FTZ-Factor1 (FTZ-F1) protein is a conserved member of the nuclear receptor superfamily, but was previously thought to lack an AF2 motif, a motif that is required for ligand and coactivator binding. Here we show that FTZ-F1 does have an AF2 motif and that it is required to bind a coactivator, the homeodomain-containing protein Fushi tarazu (FTZ). We also show that FTZ contains an AF2-interacting nuclear receptor box, the first to be found in a homeodomain protein. Both interaction motifs are shown to be necessary for physical interactions in vitro and for functional interactions in developing embryos. These unexpected findings have important implications for the conserved homologs of the two proteins. PMID:11157757

  12. 25-Hydroxyvitamin D3 1-Alpha-Hydroxylase-Dependent Stimulation of Renal Klotho Expression by Spironolactone

    Directory of Open Access Journals (Sweden)

    Ioana Alesutan

    2013-11-01

    Full Text Available Background: Klotho, a transmembrane protein, protease and hormone mainly expressed in kidney, is required for the suppression of 1,25(OH2D3-generating 25-hydroxyvitamin D3 1-alpha-hydroxylase (Cyp27b1 by FGF23. Conversely, 1,25(OH2D3 stimulates, by activating the vitamin D3 receptor (Vdr, the expression of klotho, thus establishing a negative feedback loop. Klotho protects against renal and vascular injury. Klotho deficiency accelerates aging and early death, effects at least partially due to excessive formation of 1,25(OH2D3 and subsequent hyperphosphatemia. Klotho expression is inhibited by aldosterone. The present study explored the interaction of aldosterone and DOCA as well as the moderately selective mineralocorticoid receptor antagonist spironolactone on klotho expression. Methods: mRNA levels were determined utilizing quantitative RT-PCR in human embryonic kidney cells (HEK293 or in renal tissues from mice without or with prior mineralocorticoid (aldosterone or DOCA and/or spironolactone treatment. In HEK293 cells, protein levels were determined by western blotting. The experiments in HEK293 cells were performed without or with silencing of CYP27B1, of vitamin D3 receptor (VDR or of mineralocorticoid receptor (NR3C2. Results: In HEK293 cells aldosterone and in mice DOCA significantly decreased KLOTHO gene expression, effects opposed by spironolactone treatment. Spironolactone treatment alone significantly increased KLOTHO and CYP27B1 transcript levels in HEK293 cells (24 hours and mice (8 hours or 5 days. Moreover, spironolactone significantly increased klotho and CYP27B1 protein levels in HEK293 cells (48 hours. Reduced NR3C2 expression following silencing did not significantly affect KLOTHO and CYP27B1 transcript levels in presence or absence of spironolactone. Silencing of CYP27B1 and VDR significantly blunted the stimulating effect of spironolactone on KLOTHO mRNA levels in HEK293 cells. Conclusion: Besides blocking the effects of

  13. DNA sequence variants in PPARGC1A, a gene encoding a coactivator of the ω-3 LCPUFA sensing PPAR-RXR transcription complex, are associated with NV AMD and AMD-associated loci in genes of complement and VEGF signaling pathways.

    Directory of Open Access Journals (Sweden)

    John Paul SanGiovanni

    Full Text Available Increased intake of ω-3 long-chain polyunsaturated fatty acids (LCPUFAs and use of peroxisome proliferator activator receptor (PPAR-activating drugs are associated with attenuation of pathologic retinal angiogenesis. ω-3 LCPUFAs are endogenous agonists of PPARs. We postulated that DNA sequence variation in PPAR gamma (PPARG co-activator 1 alpha (PPARGC1A, a gene encoding a co-activator of the LCPUFA-sensing PPARG-retinoid X receptor (RXR transcription complex, may influence neovascularization (NV in age-related macular degeneration (AMD.We applied exact testing methods to examine distributions of DNA sequence variants in PPARGC1A for association with NV AMD and interaction of AMD-associated loci in genes of complement, lipid metabolism, and VEGF signaling systems. Our sample contained 1858 people from 3 elderly cohorts of western European ancestry. We concurrently investigated retinal gene expression profiles in 17-day-old neonatal mice on a 2% LCPUFA feeding paradigm to identify LCPUFA-regulated genes both associated with pathologic retinal angiogenesis and known to interact with PPARs or PPARGC1A.A DNA coding variant (rs3736265 and a 3'UTR-resident regulatory variant (rs3774923 in PPARGC1A were independently associated with NV AMD (exact P = 0.003, both SNPs. SNP-SNP interactions existed for NV AMD (P<0.005 with rs3736265 and a AMD-associated variant in complement factor B (CFB, rs512559. PPARGC1A influences activation of the AMD-associated complement component 3 (C3 promoter fragment and CFB influences activation and proteolysis of C3. We observed interaction (P ≤ 0.003 of rs3736265 with a variant in vascular endothelial growth factor A (VEGFA, rs3025033, a key molecule in retinal angiogenesis. Another PPARGC1A coding variant (rs8192678 showed statistical interaction with a SNP in the VEGFA receptor fms-related tyrosine kinase 1 (FLT1, rs10507386; P ≤ 0.003. C3 expression was down-regulated 2-fold in retinas of ω-3 LCPUFA-fed mice

  14. DNA sequence variants in PPARGC1A, a gene encoding a coactivator of the ω-3 LCPUFA sensing PPAR-RXR transcription complex, are associated with NV AMD and AMD-associated loci in genes of complement and VEGF signaling pathways.

    Science.gov (United States)

    SanGiovanni, John Paul; Chen, Jing; Sapieha, Przemyslaw; Aderman, Christopher M; Stahl, Andreas; Clemons, Traci E; Chew, Emily Y; Smith, Lois E H

    2013-01-01

    Increased intake of ω-3 long-chain polyunsaturated fatty acids (LCPUFAs) and use of peroxisome proliferator activator receptor (PPAR)-activating drugs are associated with attenuation of pathologic retinal angiogenesis. ω-3 LCPUFAs are endogenous agonists of PPARs. We postulated that DNA sequence variation in PPAR gamma (PPARG) co-activator 1 alpha (PPARGC1A), a gene encoding a co-activator of the LCPUFA-sensing PPARG-retinoid X receptor (RXR) transcription complex, may influence neovascularization (NV) in age-related macular degeneration (AMD). We applied exact testing methods to examine distributions of DNA sequence variants in PPARGC1A for association with NV AMD and interaction of AMD-associated loci in genes of complement, lipid metabolism, and VEGF signaling systems. Our sample contained 1858 people from 3 elderly cohorts of western European ancestry. We concurrently investigated retinal gene expression profiles in 17-day-old neonatal mice on a 2% LCPUFA feeding paradigm to identify LCPUFA-regulated genes both associated with pathologic retinal angiogenesis and known to interact with PPARs or PPARGC1A. A DNA coding variant (rs3736265) and a 3'UTR-resident regulatory variant (rs3774923) in PPARGC1A were independently associated with NV AMD (exact P = 0.003, both SNPs). SNP-SNP interactions existed for NV AMD (Pcomplement factor B (CFB, rs512559). PPARGC1A influences activation of the AMD-associated complement component 3 (C3) promoter fragment and CFB influences activation and proteolysis of C3. We observed interaction (P ≤ 0.003) of rs3736265 with a variant in vascular endothelial growth factor A (VEGFA, rs3025033), a key molecule in retinal angiogenesis. Another PPARGC1A coding variant (rs8192678) showed statistical interaction with a SNP in the VEGFA receptor fms-related tyrosine kinase 1 (FLT1, rs10507386; P ≤ 0.003). C3 expression was down-regulated 2-fold in retinas of ω-3 LCPUFA-fed mice - these animals also showed 70% reduction in retinal NV (P

  15. Targeting AR Variant-Coactivator Interactions to Exploit Prostate Cancer Vulnerabilities.

    Science.gov (United States)

    Magani, Fiorella; Peacock, Stephanie O; Rice, Meghan A; Martinez, Maria J; Greene, Ann M; Magani, Pablo S; Lyles, Rolando; Weitz, Jonathan R; Burnstein, Kerry L

    2017-11-01

    Castration-resistant prostate cancer (CRPC) progresses rapidly and is incurable. Constitutively active androgen receptor splice variants (AR-Vs) represent a well-established mechanism of therapeutic resistance and disease progression. These variants lack the AR ligand-binding domain and, as such, are not inhibited by androgen deprivation therapy (ADT), which is the standard systemic approach for advanced prostate cancer. Signaling by AR-Vs, including the clinically relevant AR-V7, is augmented by Vav3, an established AR coactivator in CRPC. Using mutational and biochemical studies, we demonstrated that the Vav3 Diffuse B-cell lymphoma homology (DH) domain interacted with the N-terminal region of AR-V7 (and full length AR). Expression of the Vav3 DH domain disrupted Vav3 interaction with and enhancement of AR-V7 activity. The Vav3 DH domain also disrupted AR-V7 interaction with other AR coactivators: Src1 and Vav2, which are overexpressed in PC. This Vav3 domain was used in proof-of-concept studies to evaluate the effects of disrupting the interaction between AR-V7 and its coactivators on CRPC cells. This disruption decreased CRPC cell proliferation and anchorage-independent growth, caused increased apoptosis, decreased migration, and resulted in the acquisition of morphological changes associated with a less aggressive phenotype. While disrupting the interaction between FL-AR and its coactivators decreased N-C terminal interaction, disrupting the interaction of AR-V7 with its coactivators decreased AR-V7 nuclear levels. Implications: This study demonstrates the potential therapeutic utility of inhibiting constitutively active AR-V signaling by disrupting coactivator binding. Such an approach is significant, as AR-Vs are emerging as important drivers of CRPC that are particularly recalcitrant to current therapies. Mol Cancer Res; 15(11); 1469-80. ©2017 AACR . ©2017 American Association for Cancer Research.

  16. Transcriptional regulation of human and rat hepatic lipid metabolism by the grapefruit flavonoid naringenin: role of PPARalpha, PPARgamma and LXRalpha.

    Directory of Open Access Journals (Sweden)

    Jonathan Goldwasser

    2010-08-01

    Full Text Available Disruption of lipid and carbohydrate homeostasis is an important factor in the development of prevalent metabolic diseases such as diabetes, obesity, and atherosclerosis. Therefore, small molecules that could reduce insulin dependence and regulate dyslipidemia could have a dramatic effect on public health. The grapefruit flavonoid naringenin has been shown to normalize lipids in diabetes and hypercholesterolemia, as well as inhibit the production of HCV. Here, we demonstrate that naringenin regulates the activity of nuclear receptors PPARalpha, PPARgamma, and LXRalpha. We show it activates the ligand-binding domain of both PPARalpha and PPARgamma, while inhibiting LXRalpha in GAL4-fusion reporters. Using TR-FRET, we show that naringenin is a partial agonist of LXRalpha, inhibiting its association with Trap220 co-activator in the presence of TO901317. In addition, naringenin induces the expression of PPARalpha co-activator, PGC1alpha. The flavonoid activates PPAR response element (PPRE while suppressing LXRalpha response element (LXRE in human hepatocytes, translating into the induction of PPAR-regulated fatty acid oxidation genes such as CYP4A11, ACOX, UCP1 and ApoAI, and inhibition of LXRalpha-regulated lipogenesis genes, such as FAS, ABCA1, ABCG1, and HMGR. This effect results in the induction of a fasted-like state in primary rat hepatocytes in which fatty acid oxidation increases, while cholesterol and bile acid production decreases. Our findings explain the myriad effects of naringenin and support its continued clinical development. Of note, this is the first description of a non-toxic, naturally occurring LXRalpha inhibitor.

  17. Differential coactivation in a redundant signals task with weak and strong go/no-go stimuli

    DEFF Research Database (Denmark)

    Minakata, Katsumi; Gondan, Matthias

    2018-01-01

    When participants respond to stimuli of two sources, response times (RT) are often faster when both stimuli are presented together relative to the RTs obtained when presented separately (redundant signals effect, RSE). Race models and coactivation models can explain the RSE. In race models......, separate channels process the two stimulus components, and the faster processing time determines the overall RT. In audiovisual experiments, the RSE is often higher than predicted by race models, and coactivation models have been proposed that assume integrated processing of the two stimuli. Where does...

  18. Hypoxia inducible factor-1 alpha stabilization for regenerative therapy in traumatic brain injury

    Directory of Open Access Journals (Sweden)

    Mushfiquddin Khan

    2017-01-01

    Full Text Available Mild traumatic brain injury (TBI, also called concussion, initiates sequelae leading to motor deficits, cognitive impairments and subtly compromised neurobehaviors. While the acute phase of TBI is associated with neuroinflammation and nitroxidative burst, the chronic phase shows a lack of stimulation of the neurorepair process and regeneration. The deficiency of nitric oxide (NO, the consequent disturbed NO metabolome, and imbalanced mechanisms of S-nitrosylation are implicated in blocking the mechanisms of neurorepair processes and functional recovery in the both phases. Hypoxia inducible factor-1 alpha (HIF-1α, a master regulator of hypoxia/ischemia, stimulates the process of neurorepair and thus aids in functional recovery after brain trauma. The activity of HIF-1α is regulated by NO via the mechanism of S-nitrosylation of HIF-1α. S-nitrosylation is dynamically regulated by NO metabolites such as S-nitrosoglutathione (GSNO and peroxynitrite. GSNO stabilizes, and peroxynitrite destabilizes HIF-1α. Exogenously administered GSNO was found not only to stabilize HIF-1α and to induce HIF-1α-dependent genes but also to stimulate the regeneration process and to aid in functional recovery in TBI animals.

  19. PM1-Alpha ELISA: the assay of choice for the detection of anti-PM/Scl autoantibodies?

    Science.gov (United States)

    Mahler, Michael; Fritzler, Marvin J

    2009-03-01

    A characteristic serological feature of patients suffering from the overlap polymyositis and scleroderma (PM/Scl) syndrome are antibodies to the human counterpart of the yeast exosome referred to as the PM/Scl complex. Historically, the detection of anti-PM/Scl antibodies was laborious and relied largely on indirect immunofluorescence and immunodiffusion techniques. In 1992 the major autoantigen PM/Scl-100 was identified and cloned. Subsequently, the major epitopes were mapped and one of these, termed PM1-Alpha, became the antigen for a novel ELISA exhibiting high sensitivity and specificity for the detection of anti-PM/Scl antibodies. Comparative studies with other methods using other PM/Scl autoantigens have shown that the PM1-Alpha ELISA has higher sensitivity and specificity than assays that employed recombinant PM/Scl-75c and PM/Scl-100. Anti-PM1-Alpha antibodies were identified in 55.0% of sera from PM/Scl overlap syndrome patients, but were also seen in 7.9% of SSc and in 7.5% of PM patients. The frequency in other systemic autoimmune diseases and in infectious diseases was significant lower. In summary, the data derived from individual studies suggest that PM1-Alpha may become the "gold standard" for the detection of anti-PM/Scl antibodies.

  20. Advances toward DNA-based identification and phylogeny of North American Armillaria species using elongation factor-1 alpha gene

    Science.gov (United States)

    Amy L. Ross-Davis; John W. Hanna; Mee-Sook Kim; Ned B. Klopfenstein

    2012-01-01

    The translation elongation factor-1 alpha gene was used to examine the phylogenetic relationships among 30 previously characterized isolates representing ten North American Armillaria species: A. solidipes (=A. ostoyae), A. gemina, A. calvescens, A. sinapina, A. mellea, A. gallica, A. nabsnona, North American biological species X, A. cepistipes, and A. tabescens. The...

  1. Expression of hypoxia-inducible factor 1 alpha and its downstream targets in fibroepithelial tumors of the breast

    NARCIS (Netherlands)

    Kuijper, Arno; Groep, P. van der; Wall, E. van der; Diest, P.J. van

    2005-01-01

    INTRODUCTION Hypoxia-inducible factor 1 (HIF-1) alpha and its downstream targets carbonic anhydrase IX (CAIX) and vascular endothelial growth factor (VEGF) are key factors in the survival of proliferating tumor cells in a hypoxic microenvironment. We studied the expression and prognostic relevance

  2. Effects of 1 alpha,25-Dihydroxyvitamin D-3 on Transporters and Enzymes of the Rat Intestine and Kidney In Vivo

    NARCIS (Netherlands)

    Chow, Edwin C. Y.; Sun, Huadong; Khan, Ansar A.; Groothuis, Geny M. M.; Pang, K. Sandy

    1 alpha,25-Dihydroxyvitamin D-3 (1,25(OH)(2)D-3), the natural ligand of the vitamin D receptor (VDR), was found to regulate bile acid related transporters and enzymes directly and indirectly in the rat intestine and liver in vivo. The kidney is another VDR-rich target organ in which VDR regulation

  3. Effects of medicinal cake-separated moxibustion on plasma 6-keto-PGF1alpha and TXB2 contents in the rabbit of hyperlipemia.

    Science.gov (United States)

    Xiaorong, Chang; Jie, Yan; Zenghui, Yue; Jing, Shen; Yaping, Lin; Shouxiang, Yi; Xiangping, Cao

    2005-06-01

    Hyperlipemia rabbit models established with high cholesterol and fat diet were treated with direct moxibustion and medicinal cake-separated moxibustion. The post-treatment plasma 6-keto-prostaglandin F1alpha (6-keto-PGF1alpha) and thromboxane B2 (TXB2) contents were determined by radioimmunoassay. Results indicated that the plasma 6-keto-PGF1alpha content significantly increased, the TXB2 level decreased (P keto-PGF1alpha ratio also decreased (P 0.05), suggesting that both the medicinal cake-separated moxibustion and direct moxibustion can regulate the plasma 6-keto-PGF1alpha and TXB2 contents, and the TXB2/6-keto-PGF1alpha ratio with similar actions, and have a certain protective action on endothelial cells of the aorta in the rabbit of hyperlipemia.

  4. SU-C-303-02: Correlating Metabolic Response to Radiation Therapy with HIF-1alpha Expression

    International Nuclear Information System (INIS)

    Campos, D; Peeters, W; Nickel, K; Eliceiri, K; Kimple, R; Van Der Kogel, A; Kissick, M

    2015-01-01

    Purpose: To understand radiation induced alterations in cellular metabolism which could be used to assess treatment or normal tissue response to aid in patient-specific adaptive radiotherapy. This work aims to compare the metabolic response of two head and neck cell lines, one malignant (UM-SCC-22B) and one benign (Normal Oral Keratinocyte), to ionizing radiation. Responses are compared to alterations in HIF-1alpha expression. These dynamics can potentially serve as biomarkers in assessing treatment response allowing for patient-specific adaptive radiotherapy. Methods: Measurements of metabolism and HIF-1alpha expression were taken before and X minutes after a 10 Gy dose of radiation delivered via an orthovoltage x-ray source. In vitro changes in metabolic activity were measured via fluorescence lifetime imaging (FLIM) to assess the mean lifetime of NADH autofluorescence following a dose of 10 Gy. HIF-1alpha expression was measured via immunohistochemical staining of in vitro treated cells and expression was quantified using the FIJI software package. Results: FLIM demonstrated a decrease in the mean fluorescence lifetime of NADH by 100 ps following 10 Gy indicating a shift towards glycolytic pathways for malignant cells; whereas this benign cell line showed little change in metabolic signature. Immunohistochemical analysis showed significant changes in HIF-1alpha expression in response to 10 Gy of radiation that correlate to metabolic profiles. Conclusion: Radiation induces significant changes in metabolic activity and HIF-1alpha expression. These alterations occur on time scales approximating the duration of common radiation treatments (approximately tens of minutes). Further understanding these dynamics has important implications with regard to improvement of therapy and biomarkers of treatment response

  5. SU-C-303-02: Correlating Metabolic Response to Radiation Therapy with HIF-1alpha Expression

    Energy Technology Data Exchange (ETDEWEB)

    Campos, D [University of Wisconsin Madison, Madison, WI (United States); Peeters, W [Radboud University Medical Center, Nijmegen, GA (United States); Nickel, K [University of Wisconsin, Madison, WI (United States); Eliceiri, K; Kimple, R; Van Der Kogel, A; Kissick, M [University of Wisconsin, Madison, Wisconsin (United States)

    2015-06-15

    Purpose: To understand radiation induced alterations in cellular metabolism which could be used to assess treatment or normal tissue response to aid in patient-specific adaptive radiotherapy. This work aims to compare the metabolic response of two head and neck cell lines, one malignant (UM-SCC-22B) and one benign (Normal Oral Keratinocyte), to ionizing radiation. Responses are compared to alterations in HIF-1alpha expression. These dynamics can potentially serve as biomarkers in assessing treatment response allowing for patient-specific adaptive radiotherapy. Methods: Measurements of metabolism and HIF-1alpha expression were taken before and X minutes after a 10 Gy dose of radiation delivered via an orthovoltage x-ray source. In vitro changes in metabolic activity were measured via fluorescence lifetime imaging (FLIM) to assess the mean lifetime of NADH autofluorescence following a dose of 10 Gy. HIF-1alpha expression was measured via immunohistochemical staining of in vitro treated cells and expression was quantified using the FIJI software package. Results: FLIM demonstrated a decrease in the mean fluorescence lifetime of NADH by 100 ps following 10 Gy indicating a shift towards glycolytic pathways for malignant cells; whereas this benign cell line showed little change in metabolic signature. Immunohistochemical analysis showed significant changes in HIF-1alpha expression in response to 10 Gy of radiation that correlate to metabolic profiles. Conclusion: Radiation induces significant changes in metabolic activity and HIF-1alpha expression. These alterations occur on time scales approximating the duration of common radiation treatments (approximately tens of minutes). Further understanding these dynamics has important implications with regard to improvement of therapy and biomarkers of treatment response.

  6. HIF-1alpha and HIF-2alpha are differentially activated in distinct cell populations in retinal ischaemia.

    Directory of Open Access Journals (Sweden)

    Freya M Mowat

    2010-06-01

    Full Text Available Hypoxia plays a key role in ischaemic and neovascular disorders of the retina. Cellular responses to oxygen are mediated by hypoxia-inducible transcription factors (HIFs that are stabilised in hypoxia and induce the expression of a diverse range of genes. The purpose of this study was to define the cellular specificities of HIF-1alpha and HIF-2alpha in retinal ischaemia, and to determine their correlation with the pattern of retinal hypoxia and the expression profiles of induced molecular mediators.We investigated the tissue distribution of retinal hypoxia during oxygen-induced retinopathy (OIR in mice using the bio-reductive drug pimonidazole. We measured the levels of HIF-1alpha and HIF-2alpha proteins by Western blotting and determined their cellular distribution by immunohistochemistry during the development of OIR. We measured the temporal expression profiles of two downstream mediators, vascular endothelial growth factor (VEGF and erythropoietin (Epo by ELISA. Pimonidazole labelling was evident specifically in the inner retina. Labelling peaked at 2 hours after the onset of hypoxia and gradually declined thereafter. Marked binding to Müller glia was evident during the early hypoxic stages of OIR. Both HIF-1alpha and HIF-2alpha protein levels were significantly increased during retinal hypoxia but were evident in distinct cellular distributions; HIF-1alpha stabilisation was evident in neuronal cells throughout the inner retinal layers whereas HIF-2alpha was restricted to Müller glia and astrocytes. Hypoxia and HIF-alpha stabilisation in the retina were closely followed by upregulated expression of the downstream mediators VEGF and EPO.Both HIF-1alpha and HIF-2alpha are activated in close correlation with retinal hypoxia but have contrasting cell specificities, consistent with differential roles in retinal ischaemia. Our findings suggest that HIF-2alpha activation plays a key role in regulating the response of Müller glia to hypoxia.

  7. Nuclear localization of the transcriptional coactivator YAP is associated with invasive lobular breast cancer

    NARCIS (Netherlands)

    Vlug, E.J.; Ven, R.A. van de; Vermeulen, J.F.; Bult, P.; Diest, P.J. van; Derksen, P.W.B.

    2013-01-01

    BACKGROUND: Yes Associated Protein (YAP) has been implicated in the control of organ size by regulating cell proliferation and survival. YAP is a transcriptional coactivator that controls cellular responses through interaction with TEAD transcription factors in the nucleus, while its transcriptional

  8. Hamstrings co-activation in ACL-deficient subjects during isometric whole-leg extensions

    NARCIS (Netherlands)

    Aalbersberg, S.; Kingma, I.; van Dieen, J.H.

    2009-01-01

    It has been reported that anterior cruciate ligament (ACL)-deficient subjects increase the level of hamstrings activation and this has been interpreted as a means to cope with increased anterior tibial laxity in the knee. This study aimed to establish to what extent co-activation strategies in

  9. Ankle torque steadiness is related to muscle activation variability and coactivation in children with cerebral palsy

    DEFF Research Database (Denmark)

    Bandholm, Thomas; Rose, Martin Høyer; Sløk, Rikke

    2009-01-01

    The aims of this study were to: (1) investigate the significance of muscle activation variability and coactivation for the ability to perform steady submaximal ankle torque (torque steadiness) in healthy children and those with cerebral palsy (CP), and (2) assess ankle function during isometric...

  10. The Race that Precedes Coactivation: Development of Multisensory Facilitation in Children

    Science.gov (United States)

    Barutchu, Ayla; Crewther, David P.; Crewther, Sheila G.

    2009-01-01

    Rationale: The facilitating effect of multisensory integration on motor responses in adults is much larger than predicted by race-models and is in accordance with the idea of coactivation. However, the development of multisensory facilitation of endogenously driven motor processes and its relationship to the development of complex cognitive skills…

  11. Ligand-independent recruitment of steroid receptor coactivators to estrogen receptor by cyclin D1

    NARCIS (Netherlands)

    Zwijsen, R.M.L.; Buckle, R.S.; Hijmans, E.M.; Loomans, C.J.M.; Bernards, R.A.

    1998-01-01

    The estrogen receptor (ER) is an important regulator of growth and differentiation of breast epithelium. Transactivation by ER depends on a leucine-rich motif, which constitutes a ligand-regulated binding site for steroid receptor coactivators (SRCs). Cyclin D1 is frequently amplified in breast

  12. SRC-2 is an essential coactivator for orchastrating metabolism and circadian rhythm

    Science.gov (United States)

    Synchrony of the mammalian circadian clock is achieved by complex transcriptional and translational feedback loops centered on the BMAL1:CLOCK heterodimer. Modulation of circadian feedback loops is essential for maintaining rhythmicity, yet the role of transcriptional coactivators in driving BMAL1:C...

  13. Targeted disruption of the CREB coactivator Crtc2 increases insulin sensitivity

    DEFF Research Database (Denmark)

    Wang, Yiguo; Inoue, Hiroshi; Ravnskjær, Kim

    2010-01-01

    Under fasting conditions, increases in circulating concentrations of pancreatic glucagon maintain glucose homeostasis through induction of gluconeogenic genes by the CREB coactivator CRTC2. Hepatic CRTC2 activity is elevated in obesity, although the extent to which this cofactor contributes to at...

  14. Epstein-Barr Virus Nuclear Antigen Leader Protein Coactivates EP300.

    Science.gov (United States)

    Wang, Chong; Zhou, Hufeng; Xue, Yong; Liang, Jun; Narita, Yohei; Gerdt, Catherine; Zheng, Amy Y; Jiang, Runsheng; Trudeau, Stephen; Peng, Chih-Wen; Gewurz, Benjamin E; Zhao, Bo

    2018-05-01

    Epstein-Barr virus nuclear antigen (EBNA) leader protein (EBNALP) is one of the first viral genes expressed upon B-cell infection. EBNALP is essential for EBV-mediated B-cell immortalization. EBNALP is thought to function primarily by coactivating EBNA2-mediated transcription. Chromatin immune precipitation followed by deep sequencing (ChIP-seq) studies highlight that EBNALP frequently cooccupies DNA sites with host cell transcription factors (TFs), in particular, EP300, implicating a broader role in transcription regulation. In this study, we investigated the mechanisms of EBNALP transcription coactivation through EP300. EBNALP greatly enhanced EP300 transcription activation when EP300 was tethered to a promoter. EBNALP coimmunoprecipitated endogenous EP300 from lymphoblastoid cell lines (LCLs). EBNALP W repeat serine residues 34, 36, and 63 were required for EP300 association and coactivation. Deletion of the EP300 histone acetyltransferase (HAT) domain greatly reduced EBNALP coactivation and abolished the EBNALP association. An EP300 bromodomain inhibitor also abolished EBNALP coactivation and blocked the EP300 association with EBNALP. EBNALP sites cooccupied by EP300 had significantly higher ChIP-seq signals for sequence-specific TFs, including SPI1, RelA, EBF1, IRF4, BATF, and PAX5. EBNALP- and EP300-cooccurring sites also had much higher H3K4me1 and H3K27ac signals, indicative of activated enhancers. EBNALP-only sites had much higher signals for DNA looping factors, including CTCF and RAD21. EBNALP coactivated reporters under the control of NF-κB or SPI1. EP300 inhibition abolished EBNALP coactivation of these reporters. Clustered regularly interspaced short palindromic repeat interference targeting of EBNALP enhancer sites significantly reduced target gene expression, including that of EP300 itself. These data suggest a previously unrecognized mechanism by which EBNALP coactivates transcription through subverting of EP300 and thus affects the expression of

  15. Genetic evidence that HNF-1alpha-dependent transcriptional control of HNF-4alpha is essential for human pancreatic beta cell function

    DEFF Research Database (Denmark)

    Hansen, Sara K; Párrizas, Marcelina; Jensen, Maria L

    2002-01-01

    Mutations in the genes encoding hepatocyte nuclear factor 4alpha (HNF-4alpha) and HNF-1alpha impair insulin secretion and cause maturity onset diabetes of the young (MODY). HNF-4alpha is known to be an essential positive regulator of HNF-1alpha. More recent data demonstrates that HNF-4alpha...... in human islets and exocrine cells is primarily mediated by the P2 promoter. Furthermore, we describe a G --> A mutation in a conserved nucleotide position of the HNF-1alpha binding site of the P2 promoter, which cosegregates with MODY. The mutation results in decreased affinity for HNF-1alpha...

  16. Chemokines, macrophage inflammatory protein-2 and stromal cell-derived factor-1{alpha}, suppress amyloid {beta}-induced neurotoxicity

    Energy Technology Data Exchange (ETDEWEB)

    Raman, Dayanidhi; Milatovic, Snjezana-Zaja [Department of Cancer Biology, Vanderbilt University, School of Medicine, Nashville, TN 37232 (United States); Milatovic, Dejan [Department of Pediatrics/Pediatric Toxicology, Vanderbilt University, School of Medicine, Nashville, TN 37232 (United States); Splittgerber, Ryan [Department of Cancer Biology, Vanderbilt University, School of Medicine, Nashville, TN 37232 (United States); Fan, Guo-Huang [Department of Neurobiology and Neurotoxicology, Meharry Medical College, Nashville, TN 37221 (United States); Richmond, Ann, E-mail: ann.richmond@vanderbilt.edu [VA Medical Center, Nashville, TN 37232 (United States); Department of Cancer Biology, Vanderbilt University, School of Medicine, Nashville, TN 37232 (United States)

    2011-11-15

    Alzheimer's disease (AD) is characterized by a progressive cognitive decline and accumulation of neurotoxic oligomeric peptides amyloid-{beta} (A{beta}). Although the molecular events are not entirely known, it has become evident that inflammation, environmental and other risk factors may play a causal, disruptive and/or protective role in the development of AD. The present study investigated the ability of the chemokines, macrophage inflammatory protein-2 (MIP-2) and stromal cell-derived factor-1{alpha} (SDF-1{alpha}), the respective ligands for chemokine receptors CXCR2 and CXCR4, to suppress A{beta}-induced neurotoxicity in vitro and in vivo. Pretreatment with MIP-2 or SDF-1{alpha} significantly protected neurons from A{beta}-induced dendritic regression and apoptosis in vitro through activation of Akt, ERK1/2 and maintenance of metalloproteinase ADAM17 especially with SDF-1{alpha}. Intra-cerebroventricular (ICV) injection of A{beta} led to reduction in dendritic length and spine density of pyramidal neurons in the CA1 area of the hippocampus and increased oxidative damage 24 h following the exposure. The A{beta}-induced morphometric changes of neurons and increase in biomarkers of oxidative damage, F{sub 2}-isoprostanes, were significantly inhibited by pretreatment with the chemokines MIP-2 or SDF-1{alpha}. Additionally, MIP-2 or SDF-1{alpha} was able to suppress the aberrant mislocalization of p21-activated kinase (PAK), one of the proteins involved in the maintenance of dendritic spines. Furthermore, MIP-2 also protected neurons against A{beta} neurotoxicity in CXCR2-/- mice, potentially through observed up regulation of CXCR1 mRNA. Understanding the neuroprotective potential of chemokines is crucial in defining the role for their employment during the early stages of neurodegeneration. -- Research highlights: Black-Right-Pointing-Pointer Neuroprotective ability of the chemokines MIP2 and CXCL12 against A{beta} toxicity. Black-Right-Pointing-Pointer MIP

  17. Interleukin-1 alpha modulates collagen gene expression in cultured synovial cells.

    Science.gov (United States)

    Mauviel, A; Teyton, L; Bhatnagar, R; Penfornis, H; Laurent, M; Hartmann, D; Bonaventure, J; Loyau, G; Saklatvala, J; Pujol, J P

    1988-01-01

    The effects of porcine interleukin-1 (IL-1) alpha on collagen production were studied in cultured human rheumatoid synovial cells. Addition of 0.05-5 ng of IL-1/ml into the cultures resulted in a dose-dependent decreased rate of collagen released into the medium over 24 h. To determine whether this inhibition was due to secondary action of prostaglandin E2 (PGE2) secreted in response to IL-1, cultures were incubated in presence of various inhibitors of arachidonate metabolism. Depending on the cell strains, these inhibitors were able to suppress or diminish the effect of IL-1, suggesting that PGE2 is involved in the mechanism. Depression of collagen production caused by IL-1 mainly affected type I collagen and therefore led to a change in the type I/type III collagen ratio in the extracellular medium. Steady-state levels of mRNA for types I and III procollagens were estimated by dot-blot hybridization and compared with the amounts of respective collagens produced in the same cultures. IL-1 generally increased procollagen type I mRNA, but to a variable extent, as did indomethacin (Indo). Depending on the cell strain, the combination of indo and IL-1 could elevate the mRNA level of type I procollagen compared with Indo alone. These results did not correlate with the production rate of collagen in the medium, which was diminished by exposure to IL-1. The level of mRNA for collagen type III was not greatly changed by incubation with IL-1, and a better correlation was generally observed with the amount of type III collagen found in the medium. These data suggest that an additional control mechanism at translational or post-translational level must exist, counterbalancing the stimulatory effect of IL-1 on collagen mRNA transcription. It is likely that IL-1 could modulate the production of collagen in synovial cells by an interplay of different mechanisms, some of them limiting the effect of primary elevation of the steady-state mRNA level. Images Fig. 3. Fig. 4. Fig. 5

  18. Hypoxia-inducible factor 1 alpha expression increases during colorectal carcinogenesis and tumor progression

    International Nuclear Information System (INIS)

    Simiantonaki, Nektaria; Taxeidis, Marios; Jayasinghe, Caren; Kurzik-Dumke, Ursula; Kirkpatrick, Charles James

    2008-01-01

    Hypoxia-inducible factor 1 alpha (HIF-1α) is involved in processes promoting carcinogenesis of many tumors. However, its role in the development of colorectal cancer is unknown. To investigate the significance of HIF-1α during colorectal carcinogenesis and progression we examined its expression in precursor lesions constituting the conventional and serrated pathways, as well as in non-metastatic and metastatic adenocarcinomas. Immunohistochemistry and Western blot is used to analyse HIF-1α expression in normal colonic mucosa, hyperplastic polyps (HPP), sessile serrated adenomas (SSA), low-grade (TA-LGD) and high-grade (TA-HGD) traditional adenomas as well as in non-metastatic and metastatic colorectal adenocarcinomas. Eight colorectal carcinoma cell lines are tested for their HIF-1α inducibility after lipopolysaccharide (LPS) stimulation using western blot and immunocytochemistry. In normal mucosa, HPP and TA-LGD HIF-1α was not expressed. In contast, perinuclear protein accumulation and nuclear expression of HIF-1α were shown in half of the examined SSA and TA-HGD. In all investigated colorectal carcinomas a significant nuclear HIF-1α overexpression compared to the premalignant lesions was observed but a significant correlation with the metastatic status was not found. Nuclear HIF-1α expression was strongly accumulated in perinecrotic regions. In these cases HIF-1α activation was seen in viable cohesive tumor epithelia surrounding necrosis and in dissociated tumor cells, which subsequently die. Enhanced distribution of HIF-1α was also seen in periiflammatory regions. In additional in vitro studies, treatment of diverse colorectal carcinoma cell lines with the potent pro-inflammatory factor lipopolysaccharide (LPS) led to HIF-1α expression and nuclear translocation. We conclude that HIF-1α expression occurs in early stages of colorectal carcinogenesis and achieves a maximum in the invasive stage independent of the metastatic status. Perinecrotic

  19. Small interfering RNA targeting HIF-1{alpha} reduces hypoxia-dependent transcription and radiosensitizes hypoxic HT 1080 human fibrosarcoma cells in vitro

    Energy Technology Data Exchange (ETDEWEB)

    Staab, Adrian [Wuerzburg Univ. (Germany). Dept. of Radiation Oncology; Paul Scherrer Institute (PSI), Villigen (Switzerland); Fleischer, Markus [Wuerzburg Univ. (Germany). Dept. of Radiation Oncology; Wuerzburg Univ. (Germany). Medical Clinic II; Loeffler, Juergen; Einsele, Herrmann [Wuerzburg Univ. (Germany). Medical Clinic II; Said, Harun M.; Katzer, Astrid; Flentje, Michael [Wuerzburg Univ. (Germany). Dept. of Radiation Oncology; Plathow, Christian [Freiburg Univ. (Germany). Dept. of Nuclear Medicine; Vordermark, Dirk [Wuerzburg Univ. (Germany). Dept. of Radiation Oncology; Halle-Wittenberg Univ. (Germany). Dept. of Radiation Oncology

    2011-04-15

    Background: Hypoxia inducible factor-1 has been identified as a potential target to overcome hypoxia-induced radioresistance The aim of the present study was to investigate whether selective HIF-1 inhibition via small interfering RNA (siRNA) targeting hypoxia-inducible factor 1{alpha} (HIF-1{alpha}) affects hypoxia-induced radioresistance in HT 1080 human fibrosarcoma cells. Material and Methods: HIF-1{alpha} expression in HT 1080 human fibrosarcoma cells in vitro was silenced using HIF-1{alpha} siRNA sequence primers. Quantitative real-time polymerase chain reaction assay was performed to quantify the mRNA expression of HIF-1{alpha}. HIF-1{alpha} protein levels were studied by Western blotting at 20% (air) or after 12 hours at 0.1% O{sub 2} (hypoxia). Cells were assayed for clonogenic survival after irradiation with 2, 5, or 10 Gy, under normoxic or hypoxic conditions in the presence of HIF-1{alpha}-targeted or control siRNA sequences. A modified oxygen enhancement ratio (OER') was calculated as the ratio of the doses to achieve the same survival at 0.1% O{sub 2} as at ambient oxygen tensions. OER' was obtained at cell survival levels of 50%, 37%, and 10%. Results: HIF-1{alpha}-targeted siRNA enhanced radiation treatment efficacy under severely hypoxic conditions compared to tumor cells treated with scrambled control siRNA. OER was reduced on all survival levels after treatment with HIF-1{alpha}-targeted siRNA, suggesting that inhibition of HIF-1 activation by using HIF-1{alpha}-targeted siRNA increases radiosensitivity of hypoxic tumor cells in vitro. Conclusion: Inhibition of HIF-1 activation by using HIF-1{alpha}-targeted siRNA clearly acts synergistically with radiotherapy and increase radiosensitivity of hypoxic cells in vitro. (orig.)

  20. The contribution of VHL substrate binding and HIF1-alpha to the phenotype of VHL loss in renal cell carcinoma.

    Science.gov (United States)

    Maranchie, Jodi K; Vasselli, James R; Riss, Joseph; Bonifacino, Juan S; Linehan, W Marston; Klausner, Richard D

    2002-04-01

    Clear-cell renal carcinoma is associated with inactivation of the von Hippel-Lindau (VHL) tumor suppressor gene. VHL is the substrate recognition subunit of an E3 ligase, known to target the alpha subunits of the HIF heterodimeric transcription factor for ubiquitin-mediated degradation under normoxic conditions. We demonstrate that competitive inhibition of the VHL substrate recognition site with a peptide derived from the oxygen degradation domain of HIF1alpha recapitulates the tumorigenic phenotype of VHL-deficient tumor cells. These studies prove that VHL substrate recognition is essential to the tumor suppressor function of VHL. We further demonstrate that normoxic stabilization of HIF1alpha alone, while capable of mimicking some aspects of VHL loss, is not sufficient to reproduce tumorigenesis, indicating that it is not the critical oncogenic substrate of VHL.

  1. [Experimental study on aging effect of Angelica sinensis polysaccharides combined with cytarabine on human leukemia KG1alpha cell lines].

    Science.gov (United States)

    Xu, Chun-Yan; Geng, Shan; Liu, Jun; Zhu, Jia-Hong; Zhang, Xian-Ping; Jiang, Rong; Wang, Ya-Ping

    2014-04-01

    The latest findings of our laboratory showed that Angelica sinensis polysaccharide (ASP) showed a definite effect in regulating the aging of hematopoietic stem cells. Leukemia is a type of malignant hematopoietic tumor in hematopoietic stem cells. There have been no relevant reports about ASP's effect in regulating the aging of leukemia cells. In this study, human acute myeloid leukemia (AML) KG1alpha cell lines in logarithmic growth phase were taken as the study object, and were divided into the ASP group, the cytarabine (Ara-C) group, the ASP + Ara-C group and the control group. The groups were respectively treated with different concentration of ASP, Ara-C and ASP + Ara-C for different periods, with the aim to study the effect of ASP combined with Ara-C in regulating the aging of human acute myeloid leukemia KG1alpha cell lines and its relevant mechanism. The results showed that ASP, Ara-C and ASP + Ara-C could obviously inhibit KG1alpha cell proliferation in vitro, block the cells in G0/G1 phase. The cells showed the aging morphological feature. The percentage of positive stained aging cells was dramatically increased, and could significantly up-regulate the expression of aging-related proteins P16 and RB, which were more obvious in the ASP + Ara-C group. In conclusion, the aging mechanism of KG1alpha cell induced by ASP and Ara-C may be related to the regulation of the expression of aging-related proteins, suggesting that the combined administration of ASP and anticancer drugs plays a better role in the treatment of leukemia .

  2. Increased susceptibility of HIF-1 alpha heterozygous-null mice to cardiovascular malformations associated with maternal diabetes

    Czech Academy of Sciences Publication Activity Database

    Bohuslavová, Romana; Škvorová, Lada; Sedmera, David; Semenza, G.L.; Pavlínková, Gabriela

    2013-01-01

    Roč. 60, Jul (2013), s. 129-141 ISSN 0022-2828 R&D Projects: GA ČR GA301/09/0117; GA ČR(CZ) GAP302/11/1308 Institutional research plan: CEZ:AV0Z50520701 Institutional support: RVO:67985823 Keywords : Diabetic embryopathy * Heart defect * Hypoxia-inducible factor 1 alpha Subject RIV: EB - Genetics ; Molecular Biology; FA - Cardiovascular Diseases incl. Cardiotharic Surgery (FGU-C) Impact factor: 5.218, year: 2013

  3. Regulation of gene expression by dietary Ca2+ in kidneys of 25-hydroxyvitamin D3-1 alpha-hydroxylase knockout mice.

    NARCIS (Netherlands)

    Hoenderop, J.G.J.; Chon, H.; Gkika, D.; Bluyssen, H.A.; Holstege, F.C.; St. Arnaud, R.; Braam, B.; Bindels, R.J.M.

    2004-01-01

    BACKGROUND: Pseudovitamin D deficiency rickets (PDDR) is an autosomal disease, characterized by undetectable levels of 1,25-dihydroxyvitamin D3 (1,25(OH)2D3), rickets and secondary hyperparathyroidism. Mice in which the 25-hydroxyvitamin D3-1 alpha-hydroxylase (1 alpha-OHase) gene was inactivated,

  4. Direct chemical synthesis of 1 alpha,25-dihydroxy[26,27-3H] vitamin D3 with high specific activity: its use in receptor studies

    International Nuclear Information System (INIS)

    Napoli, J.L.; Mellon, W.S.; Fivizzani, M.A.; Schnoes, H.K.; DeLuca, H.F.

    1980-01-01

    The first direct chemical synthesis of radiolabeled 1 alpha, 25-dihydroxyvitamin D3 is reported. Unlike all previous syntheses, the new approach does not rely on enzymatic 1 alpha-hydroxylation of radiolabeled precursors. Rather, isotope is introduced in the last synthetic step by reaction of [3H] -methylmagnesium bromide with methyl 1 alpha-hydroxy-26,27-dinorvitamin D3-25-carboxylate to give 1 alpha,25-dihydroxy-[26,27-3H] vitamin D3 with a specific activity of 160 Ci/mmol. Mass spectroscopy confirmed that the radiohormone consists of a single isomer with six tritium atoms bound to carbons 26 and 27. Synthetically produced 1 alpha,25-dihydroxy [26,27-3H] vitamin D3 is indistinguishable from 1 alpha,25-dihydroxy-[26,27-3H] vitamin D3 obtained from the enzymatic 1 alpha-hydroxylation of 25-hydroxy[26,27-3H] vitamin D3 (160 Ci/mmol) by high-pressure liquid chromatography analysis and in the competitive binding assay using chick intestinal cytosol as the receptor source. Equilibrium dissociation constant measurements with the high specific activity radiohormone indicate a Kd of 8.2 x 10(-11) M for the chick intestinal cytosol 1 alpha,25-dihydroxyvitamin D3 receptor--a value considerably lower than the constants in the range of (1-5) x 10(-9) M previously reported

  5. Downregulation of MIP-1alpha/CCL3 with praziquantel treatment in Schistosoma haematobium and HIV-1 co-infected individuals in a rural community in Zimbabwe

    DEFF Research Database (Denmark)

    Zinyama-Gutsire, Rbl; Gomo, E.; Kallestrup, P

    2009-01-01

    influence. METHODS: To determine levels of MIP-1alpha/CCL3 chemokine in plasma of S. haematobium and HIV-1 co-infected and uninfected individuals in a rural black Zimbabwean community.A cohort was established of HIV-1 and schistosomiasis infection and co-infection comprising 379 participants. Outcome...... measures consisted of HIV-1 and schistosomiasis status and levels of MIP-1alpha/CCL3 in plasma at baseline and three months post treatment. An association was established between MIP-1alpha/CCL3 plasma levels with HIV-1 and S. haematobium infections. RESULTS: A total of 379 adults formed the established...... cohort comprising 76 (20%) men and 303 (80%) women. Mean age was 33.25, range 17 - 62 years. The median MIP-1alpha/CCL3 plasma concentration was significantly higher in S. haematobium infected compared with uninfected individuals (p = 0.029). In contrast, there was no difference in the median MIP-1alpha...

  6. Conformational selection in the molten globule state of the nuclear coactivator binding domain of CBP

    DEFF Research Database (Denmark)

    Kjærgaard, Magnus; Teilum, Kaare; Poulsen, Flemming M

    2010-01-01

    Native molten globules are the most folded kind of intrinsically disordered proteins. Little is known about the mechanism by which native molten globules bind to their cognate ligands to form fully folded complexes. The nuclear coactivator binding domain (NCBD) of CREB binding protein is particul......Native molten globules are the most folded kind of intrinsically disordered proteins. Little is known about the mechanism by which native molten globules bind to their cognate ligands to form fully folded complexes. The nuclear coactivator binding domain (NCBD) of CREB binding protein....... Biophysical studies show that despite the molten globule nature of the domain, it contains a small cooperatively folded core. By NMR spectroscopy, we have demonstrated that the folded core of NCBD has a well ordered conformer with specific side chain packing. This conformer resembles the structure of the NCBD...

  7. Listening to Puns Elicits the Co-Activation of Alternative Homophone Meanings during Language Production.

    Directory of Open Access Journals (Sweden)

    Sebastian Benjamin Rose

    Full Text Available Recent evidence suggests that lexical-semantic activation spread during language production can be dynamically shaped by contextual factors. In this study we investigated whether semantic processing modes can also affect lexical-semantic activation during word production. Specifically, we tested whether the processing of linguistic ambiguities, presented in the form of puns, has an influence on the co-activation of unrelated meanings of homophones in a subsequent language production task. In a picture-word interference paradigm with word distractors that were semantically related or unrelated to the non-depicted meanings of homophones we found facilitation induced by related words only when participants listened to puns before object naming, but not when they heard jokes with unambiguous linguistic stimuli. This finding suggests that a semantic processing mode of ambiguity perception can induce the co-activation of alternative homophone meanings during speech planning.

  8. Ablation of Steroid Receptor Coactivator-3 resembles the human CACT metabolic myopathy

    OpenAIRE

    York, Brian; Reineke, Erin L.; Sagen, Jørn V.; Nikolai, Bryan C.; Zhou, Suoling; Louet, Jean-Francois; Chopra, Atul R.; Chen, Xian; Reed, Graham; Noebels, Jeffrey; Adesina, Adekunle M.; Yu, Hui; Wong, Lee-Jun C.; Tsimelzon, Anna; Hilsenbeck, Susan

    2012-01-01

    Oxidation of lipid substrates is essential for survival in fasting and other catabolic conditions, sparing glucose for the brain and other glucose-dependent tissues. Here we show Steroid Receptor Coactivator-3 (SRC-3) plays a central role in long chain fatty acid metabolism by directly regulating carnitine/acyl-carnitine translocase (CACT) gene expression. Genetic deficiency of CACT in humans is accompanied by a constellation of metabolic and toxicity phenotypes including hypoketonemia, hypog...

  9. Development of Coactivator-Dependent, First-in-Class Therapies for Breast Cancer

    Science.gov (United States)

    2014-09-01

    y. ME65CH18-Dasgupta ARI 14 December 2013 18:9 amplified in chronic lymphocytic leukemia ( CLL ). Gain of 2p chromosomal region func- tion...inCLLpatients is detected at an early stage of the disease and correlates with poor prog- nosis, indicating SRC-1 may contribute to the pathological state of CLL ...70), recent evidence points to a require- ment for coactivators in chemoresistance (71) as well as in stem cell self-renewal and pluripo- tency

  10. A transcriptional coregulator, SPIN·DOC, attenuates the coactivator activity of Spindlin1.

    Science.gov (United States)

    Bae, Narkhyun; Gao, Min; Li, Xu; Premkumar, Tolkappiyan; Sbardella, Gianluca; Chen, Junjie; Bedford, Mark T

    2017-12-22

    Spindlin1 (SPIN1) is a transcriptional coactivator with critical functions in embryonic development and emerging roles in cancer. SPIN1 harbors three Tudor domains, two of which engage the tail of histone H3 by reading the H3-Lys-4 trimethylation and H3-Arg-8 asymmetric dimethylation marks. To gain mechanistic insight into how SPIN1 functions as a transcriptional coactivator, here we purified its interacting proteins. We identified an uncharacterized protein (C11orf84), which we renamed SPIN1 docking protein (SPIN·DOC), that directly binds SPIN1 and strongly disrupts its histone methylation reading ability, causing it to disassociate from chromatin. The Spindlin family of coactivators has five related members (SPIN1, 2A, 2B, 3, and 4), and we found that all of them bind SPIN·DOC. It has been reported previously that SPIN1 regulates gene expression in the Wnt signaling pathway by directly interacting with transcription factor 4 (TCF4). We observed here that SPIN·DOC associates with TCF4 in a SPIN1-dependent manner and dampens SPIN1 coactivator activity in TOPflash reporter assays. Furthermore, knockdown and overexpression experiments indicated that SPIN·DOC represses the expression of a number of SPIN1-regulated genes, including those encoding ribosomal RNA and the cytokine IL1B. In conclusion, we have identified SPIN·DOC as a transcriptional repressor that binds SPIN1 and masks its ability to engage the H3-Lys-4 trimethylation activation mark. © 2017 by The American Society for Biochemistry and Molecular Biology, Inc.

  11. Multi-scale complexity analysis of muscle coactivation during gait in children with cerebral palsy

    Directory of Open Access Journals (Sweden)

    Wen eTao

    2015-07-01

    Full Text Available The objective of this study is to characterize complexity of lower-extremity muscle coactivation and coordination during gait in children with cerebral palsy (CP, children with typical development (TD and healthy adults, by applying recently developed multivariate multi-scale entropy (MMSE analysis to surface EMG signals. Eleven CP children (CP group, eight TD children and seven healthy adults (consider as an entire control group were asked to walk while surface EMG signals were collected from 5 thigh muscles and 3 lower leg muscles on each leg (16 EMG channels in total. The 16-channel surface EMG data, recorded during a series of consecutive gait cycles, were simultaneously processed by multivariate empirical mode decomposition (MEMD, to generate fully aligned data scales for subsequent MMSE analysis. In order to conduct extensive examination of muscle coactivation complexity using the MEMD-enhanced MMSE, 14 data analysis schemes were designed by varying partial muscle combinations and time durations of data segments. Both TD children and healthy adults showed almost consistent MMSE curves over multiple scales for all the 14 schemes, without any significant difference (p > 0.09. However, quite diversity in MMSE curve was observed in the CP group when compared with those in the control group. There appears to be diverse neuropathological processes in CP that may affect dynamical complexity of muscle coactivation and coordination during gait. The abnormal complexity patterns emerging in CP group can be attributed to different factors such as motor control impairments, loss of muscle couplings, and spasticity or paralysis in individual muscles. All these findings expand our knowledge of neuropathology of CP from a novel point of view of muscle co-activation complexity, also indicating the potential to derive a quantitative index for assessing muscle activation characteristics as well as motor function in CP.

  12. Steroid receptor coactivators 1 and 2 mediate fetal-to-maternal signaling that initiates parturition

    OpenAIRE

    Gao, Lu; Rabbitt, Elizabeth H.; Condon, Jennifer C.; Renthal, Nora E.; Johnston, John M.; Mitsche, Matthew A.; Chambon, Pierre; Xu, Jianming; O’Malley, Bert W.; Mendelson, Carole R.

    2015-01-01

    The precise mechanisms that lead to parturition are incompletely defined. Surfactant protein-A (SP-A), which is secreted by fetal lungs into amniotic fluid (AF) near term, likely provides a signal for parturition; however, SP-A–deficient mice have only a relatively modest delay (~12 hours) in parturition, suggesting additional factors. Here, we evaluated the contribution of steroid receptor coactivators 1 and 2 (SRC-1 and SRC-2), which upregulate SP-A transcription, to the parturition process...

  13. Identification of the functional domains of ANT-1, a novel coactivator of the androgen receptor

    International Nuclear Information System (INIS)

    Fan Shuli; Goto, Kiminobu; Chen Guangchun; Morinaga, Hidetaka; Nomura, Masatoshi; Okabe, Taijiro; Nawata, Hajime; Yanase, Toshihiko

    2006-01-01

    Previously, we identified a transcriptional coactivator for the activation function-1 (AF-1) domain of the human androgen receptor (AR) and designated it androgen receptor N-terminal domain transactivating protein-1 (ANT-1). This coactivator, which contains multiple tetratricopeptide repeat (TPR) motifs from amino acid (aa) 294, is identical to a component of U5 small nuclear ribonucleoprotein particles and binds specifically to the AR or glucocorticoid receptor. Here, we identified four distinct functional domains. The AR-AF-1-binding domain, which bound to either aa 180-360 or 360-532 in AR-AF-1, clearly overlapped with TAU-1 and TAU-5. This domain and the subnuclear speckle formation domain in ANT-1 were assigned within the TPR motifs, while the transactivating and nuclear localization signal domains resided within the N-terminal sequence. The existence of these functional domains may further support the idea that ANT-1 can function as an AR-AF-1-specific coactivator while mediating a transcription-splicing coupling

  14. Phase-dependence of elbow muscle coactivation in front crawl swimming.

    Science.gov (United States)

    Lauer, Jessy; Figueiredo, Pedro; Vilas-Boas, João Paulo; Fernandes, Ricardo J; Rouard, Annie Hélène

    2013-08-01

    Propulsion in swimming is achieved by complex sculling movements with elbow quasi-fixed on the antero-posterior axis to transmit forces from the hand and the forearm to the body. The purpose of this study was to investigate how elbow muscle coactivation was influenced by the front crawl stroke phases. Ten international level male swimmers performed a 200-m front crawl race-pace bout. Sagittal views were digitized frame by frame to determine the stroke phases (aquatic elbow flexion and extension, aerial elbow flexion and extension). Surface electromyograms (EMG) of the right biceps brachii and triceps brachii were recorded and processed using the integrated EMG to calculate a coactivation index (CI) for each phase. A significant effect of the phases on the CI was revealed with highest levels of coactivation during the aquatic elbow flexion and the aerial elbow extension. Swimmers stabilize the elbow joint to overcome drag during the aquatic phase, and act as a brake at the end of the recovery to replace the arm for the next stroke. The CI can provide insight into the magnitude of mechanical constraints supported by a given joint, in particular during a complex movement. Copyright © 2013 Elsevier Ltd. All rights reserved.

  15. Cryptocephal, the Drosophila melanogaster ATF4, is a specific coactivator for ecdysone receptor isoform B2.

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    Sebastien A Gauthier

    Full Text Available The ecdysone receptor is a heterodimer of two nuclear receptors, the Ecdysone receptor (EcR and Ultraspiracle (USP. In Drosophila melanogaster, three EcR isoforms share common DNA and ligand-binding domains, but these proteins differ in their most N-terminal regions and, consequently, in the activation domains (AF1s contained therein. The transcriptional coactivators for these domains, which impart unique transcriptional regulatory properties to the EcR isoforms, are unknown. Activating transcription factor 4 (ATF4 is a basic-leucine zipper transcription factor that plays a central role in the stress response of mammals. Here we show that Cryptocephal (CRC, the Drosophila homolog of ATF4, is an ecdysone receptor coactivator that is specific for isoform B2. CRC interacts with EcR-B2 to promote ecdysone-dependent expression of ecdysis-triggering hormone (ETH, an essential regulator of insect molting behavior. We propose that this interaction explains some of the differences in transcriptional properties that are displayed by the EcR isoforms, and similar interactions may underlie the differential activities of other nuclear receptors with distinct AF1-coactivators.

  16. Expression and function of androgen receptor coactivator p44/Mep50/WDR77 in ovarian cancer.

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    Martin Ligr

    Full Text Available Hormones, including estrogen and progesterone, and their receptors play an important role in the development and progression of ovarian carcinoma. Androgen, its receptor and coactivators have also been implicated in these processes. p44/Mep50/WDR77 was identified as a subunit of the methylosome complex and lately characterized as a steroid receptor coactivator that enhances androgen receptor as well as estrogen receptor-mediated transcriptional activity in a ligand-dependent manner. We previously described distinct expression and function of p44 in prostate, testis, and breast cancers. In this report, we examined the expression and function of p44 in ovarian cancer. In contrast to findings in prostate and testicular cancer and similar to breast cancer, p44 shows strong cytoplasmic localization in morphologically normal ovarian surface and fallopian tube epithelia, while nuclear p44 is observed in invasive ovarian carcinoma. We observed that p44 can serve as a coactivator of both androgen receptor (AR and estrogen receptor (ER in ovarian cells. Further, overexpression of nuclear-localized p44 stimulates proliferation and invasion in ovarian cancer cells in the presence of estrogen or androgen. These findings strongly suggest that p44 plays a role in mediating the effects of hormones during ovarian tumorigenesis.

  17. Pax6 represses androgen receptor-mediated transactivation by inhibiting recruitment of the coactivator SPBP.

    Directory of Open Access Journals (Sweden)

    Julianne Elvenes

    Full Text Available The androgen receptor (AR has a central role in development and maintenance of the male reproductive system and in the etiology of prostate cancer. The transcription factor Pax6 has recently been reported to act as a repressor of AR and to be hypermethylated in prostate cancer cells. SPBP is a transcriptional regulator that previously has been shown to enhance the activity of Pax6. In this study we have identified SPBP to act as a transcriptional coactivator of AR. We also show that Pax6 inhibits SPBP-mediated enhancement of AR activity on the AR target gene probasin promoter, a repression that was partly reversed by increased expression of SPBP. Enhanced expression of Pax6 reduced the amount of SPBP associated with the probasin promoter when assayed by ChIP in HeLa cells. We mapped the interaction between both AR and SPBP, and AR and Pax6 to the DNA-binding domains of the involved proteins. Further binding studies revealed that Pax6 and SPBP compete for binding to AR. These results suggest that Pax6 represses AR activity by displacing and/or inhibiting recruitment of coactivators to AR target promoters. Understanding the mechanism for inhibition of AR coactivators can give rise to molecular targeted drugs for treatment of prostate cancer.

  18. Functional defect of truncated hepatocyte nuclear factor-1{alpha} (G554fsX556) associated with maturity-onset diabetes of the young

    Energy Technology Data Exchange (ETDEWEB)

    Kooptiwut, Suwattanee, E-mail: S_kooptiwut@hotmail.com [Department of Physiology, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok 10700 (Thailand); Sujjitjoon, Jatuporn [Department of Immunology and Immunology Graduate Program, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok 10700 (Thailand); Plengvidhya, Nattachet [Department of Immunology and Immunology Graduate Program, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok 10700 (Thailand); Division of Endocrinology and Metabolism, Department of Medicine, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok 10700 (Thailand); Boonyasrisawat, Watip; Chongjaroen, Nalinee; Jungtrakoon, Prapapron [Department of Immunology and Immunology Graduate Program, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok 10700 (Thailand); Semprasert, Namoiy [Department of Physiology, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok 10700 (Thailand); Furuta, Hiroto; Nanjo, Kishio [The First Department, Wakayama Medical University (Japan); Banchuin, Napatawn [Department of Immunology and Immunology Graduate Program, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok 10700 (Thailand); Yenchitsomanus, Pa-thai [Division of Medical Molecular Biology, Medicine Department of Research and Development, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok 10700 (Thailand); Medical Biotechnology Unit, National Center for Genetic Engineering and Biotechnology (BIOTEC), National Science and Technology Development Agency (NSTDA), Bangkok (Thailand)

    2009-05-22

    A novel frameshift mutation attributable to 14-nucleotide insertion in hepatocyte nuclear factor-1{alpha} (HNF-1{alpha}) encoding a truncated HNF-1{alpha} (G554fsX556) with 76-amino acid deletion at its carboxyl terminus was identified in a Thai family with maturity-onset diabetes of the young (MODY). The wild-type and mutant HNF-1{alpha} proteins were expressed by in vitro transcription and translation (TNT) assay and by transfection in HeLa cells. The wild-type and mutant HNF-1{alpha} could similarly bind to human glucose-transporter 2 (GLUT2) promoter examined by electrophoretic mobility shift assay (EMSA). However, the transactivation activities of mutant HNF-1{alpha} on human GLUT2 and rat L-type pyruvate kinase (L-PK) promoters in HeLa cells determined by luciferase reporter assay were reduced to approximately 55-60% of the wild-type protein. These results suggested that the functional defect of novel truncated HNF-1{alpha} (G554fsX556) on the transactivation of its target-gene promoters would account for the {beta}-cell dysfunction associated with the pathogenesis of MODY.

  19. 17-AAG, a Hsp90 inhibitor, attenuates the hypoxia-induced expression of SDF-1alpha and ILK in mouse RPE cells.

    Science.gov (United States)

    Wang, Ye Qing; Zhang, Xiao Mei; Wang, Xiao Dan; Wang, Bin Jie; Wang, Wei

    2010-03-01

    The aim of this study was to investigate the changes of SDF-1alpha and ILK expression in mouse retinal pigment epithelium (RPE) cells in response to hypoxia, and the effect of 17-Allylamino-17-demethoxygeldanamycin (17-AAG), a heat shock protein 90 (Hsp90) inhibitor, on the hypoxia-induced expression of SDF-1alpha and ILK. RPE cells were cultured with 200 micromol/L cobalt chloride (CoCl(2)) for different times (1, 3, 6, 12, 24, 72 h) to imitate chemical hypoxia. Pretreatment of 17-AAG was 1 h prior to hypoxic insult. Cellular viability after 17-AAG treatment was assessed by MTT assay, and the changes of SDF-1alpha and ILK expression were examined by RT-PCR and Western blot. Up-regulation of SDF-1alpha and ILK expression in response to hypoxia was observed. One hour pretreatment of 17-AAG could remarkably decreased the hypoxia-induced SDF-1alpha and ILK expression in vitro. Our results indicated that SDF-1alpha and ILK involved in the hypoxic response of RPE cells, and 1 h pretreatment of 17-AAG had an inhibitive effect on the hypoxia-induced SDF-1alpha and ILK expression.

  20. Andrographolide down-regulates hypoxia-inducible factor-1{alpha} in human non-small cell lung cancer A549 cells

    Energy Technology Data Exchange (ETDEWEB)

    Lin, Hui-Hsuan [School of Medical Laboratory and Biotechnology, Chung Shan Medical University, Taichung, Taiwan (China); Department of Medical Research, Chung Shan Medical University Hospital, Taichung, Taiwan (China); Tsai, Chia-Wen [Department of Nutrition, China Medical University, Taichung, Taiwan (China); Chou, Fen-Pi [Institute of Biochemistry and Biotechnology, Chung Shan Medical University, Taichung, Taiwan (China); Wang, Chau-Jong [Department of Medical Research, Chung Shan Medical University Hospital, Taichung, Taiwan (China); Institute of Biochemistry and Biotechnology, Chung Shan Medical University, Taichung, Taiwan (China); Hsuan, Shu-Wen [Department of Medical Laboratory Science and Biotechnology, College of Medicine and Life Science, Chung Hwa University of Medical Technology, No.89, Wen Hwa 1st St., Rende Shiang, Tainan County 717, Taiwan (China); Wang, Cheng-Kun [E-Chyun Dermatology Clinic, No.70, Sec. 3, Jhonghua E. Rd., East District, Tainan, Taiwan (China); Chen, Jing-Hsien [Department of Medical Laboratory Science and Biotechnology, College of Medicine and Life Science, Chung Hwa University of Medical Technology, No.89, Wen Hwa 1st St., Rende Shiang, Tainan County 717, Taiwan (China)

    2011-02-01

    Andrographolide (Andro), a diterpenoid lactone isolated from a traditional herbal medicine Andrographis paniculata, is known to possess multiple pharmacological activities. In our previous study, Andro had been shown to inhibit non-small cell lung cancer (NSCLC) A549 cell migration and invasion via down-regulation of phosphatidylinositol 3-kinase (PI3K)/Akt signaling pathway. Here we demonstrated that Andro inhibited the expression of hypoxia-inducible factor-1{alpha} (HIF-1{alpha}) in A549 cells. HIF-1{alpha} plays an important role in tumor growth, angiogenesis and lymph node metastasis of NSCLC. The Andro-induced decrease of cellular protein level of HIF-1{alpha} was correlated with a rapid ubiquitin-dependent degradation of HIF-1{alpha}, and was accompanied by increased expressions of hydroxyl-HIF-1{alpha} and prolyl hydroxylase (PHD2), and a later decrease of vascular endothelial growth factor (VEGF) upon the treatment of Andro. The Andro-inhibited VEGF expression appeared to be a consequence of HIF-1{alpha} inactivation, because its DNA binding activity was suppressed by Andro. Molecular data showed that all these effects of Andro might be mediated via TGF{beta}1/PHD2/HIF-1{alpha} pathway, as demonstrated by the transfection of TGF{beta}1 overexpression vector and PHD2 siRNA, and the usage of a pharmacological MG132 inhibitor. Furthermore, we elucidated the involvement of Andro in HIF-1{alpha} transduced VEGF expression in A549 cells and other NSCLC cell lines. In conclusion, these results highlighted the potential effects of Andro, which may be developed as a chemotherapeutic or an anti-angiogenesis agent for NSCLC in the future.

  1. Schedule-dependent inhibition of hypoxia-inducible factor-1alpha protein accumulation, angiogenesis, and tumor growth by topotecan in U251-HRE glioblastoma xenografts.

    Science.gov (United States)

    Rapisarda, Annamaria; Zalek, Jessica; Hollingshead, Melinda; Braunschweig, Till; Uranchimeg, Badarch; Bonomi, Carrie A; Borgel, Suzanne D; Carter, John P; Hewitt, Stephen M; Shoemaker, Robert H; Melillo, Giovanni

    2004-10-01

    We have previously shown that topotecan, a topoisomerase I poison, inhibits hypoxia-inducible factor (HIF)-1alpha protein accumulation by a DNA damage-independent mechanism. Here, we report that daily administration of topotecan inhibits HIF-1alpha protein expression in U251-HRE glioblastoma xenografts. Concomitant with HIF-1alpha inhibition, topotecan caused a significant tumor growth inhibition associated with a marked decrease of angiogenesis and expression of HIF-1 target genes in tumor tissue. These results provide a compelling rationale for testing topotecan in clinical trials to target HIF-1 in cancer patients.

  2. Expression and function of hypoxia inducible factor-1 alpha in human melanoma under non-hypoxic conditions

    Directory of Open Access Journals (Sweden)

    Joshi Sandeep S

    2009-11-01

    Full Text Available Abstract Background Hypoxia inducible factor-1 alpha (HIF-1α protein is rapidly degraded under normoxic conditions. When oxygen tensions fall HIF-1α protein stabilizes and transactivates genes involved in adaptation to hypoxic conditions. We have examined the normoxic expression of HIF-1α RNA and protein in normal human melanocytes and a series of human melanoma cell lines isolated from radial growth phase (RGP, vertical growth phase (VGP and metastatic (MET melanomas. Results HIF-1α mRNA and protein was increased in RGP vs melanocytes, VGP vs RGP and MET vs VGP melanoma cell lines. We also detected expression of a HIF-1α mRNA splice variant that lacks part of the oxygen-dependent regulation domain in WM1366 and WM9 melanoma cells. Over-expression of HIF-1α and its splice variant in the RGP cell line SbCl2 resulted in a small increase in soft agar colony formation and a large increase in matrigel invasion relative to control transfected cells. Knockdown of HIF-1α expression by siRNA in the MET WM9 melanoma cell line resulted in a large decrease in both soft agar colony formation and matrigel invasion relative to cells treated with non-specific siRNA. There is a high level of ERK1/2 phosphorylation in WM9 cells, indicating an activated Ras-Raf-MEK-ERK1/2 MAPK pathway. Treatment of WM9 cells with 30 μM U0126 MEK inhibitor, decreased ERK1/2 phosphorylation and resulted in a decrease in HIF-1α expression. However, a 24 h treatment with 10 μM U0126 totally eliminated Erk1/2 phosphorylation, but did not change HIF-1alpha levels. Furthermore, siRNA knockdown of MEK siRNA did not change HIF-1alpha levels. Conclusion We speculate that metabolic products of U0126 decrease HIF-1alpha expression through "off target" effects. Overall our data suggest that increased HIF-1α expression under normoxic conditions contributes to some of the malignant phenotypes exhibited by human melanoma cells. The expanded role of HIF-1α in melanoma biology increases

  3. Effect of acute exercise on AMPK signaling in skeletal muscle of subjects with type 2 diabetes: a time-course and dose-response study.

    Science.gov (United States)

    Sriwijitkamol, Apiradee; Coletta, Dawn K; Wajcberg, Estela; Balbontin, Gabriela B; Reyna, Sara M; Barrientes, John; Eagan, Phyllis A; Jenkinson, Christopher P; Cersosimo, Eugenio; DeFronzo, Ralph A; Sakamoto, Kei; Musi, Nicolas

    2007-03-01

    Activation of AMP-activated protein kinase (AMPK) by exercise induces several cellular processes in muscle. Exercise activation of AMPK is unaffected in lean (BMI approximately 25 kg/m(2)) subjects with type 2 diabetes. However, most type 2 diabetic subjects are obese (BMI >30 kg/m(2)), and exercise stimulation of AMPK is blunted in obese rodents. We examined whether obese type 2 diabetic subjects have impaired exercise stimulation of AMPK, at different signaling levels, spanning from the upstream kinase, LKB1, to the putative AMPK targets, AS160 and peroxisome proliferator-activated receptor coactivator (PGC)-1alpha, involved in glucose transport regulation and mitochondrial biogenesis, respectively. Twelve type 2 diabetic, eight obese, and eight lean subjects exercised on a cycle ergometer for 40 min. Muscle biopsies were done before, during, and after exercise. Subjects underwent this protocol on two occasions, at low (50% Vo(2max)) and moderate (70% Vo(2max)) intensities, with a 4-6 week interval. Exercise had no effect on LKB1 activity. Exercise had a time- and intensity-dependent effect to increase AMPK activity and AS160 phosphorylation. Obese and type 2 diabetic subjects had attenuated exercise-stimulated AMPK activity and AS160 phosphorylation. Type 2 diabetic subjects had reduced basal PGC-1 gene expression but normal exercise-induced increases in PGC-1 expression. Our findings suggest that obese type 2 diabetic subjects may need to exercise at higher intensity to stimulate the AMPK-AS160 axis to the same level as lean subjects.

  4. Cross-talk between oxysterols and glucocorticoids: differential regulation of secreted phopholipase A2 and impact on oligodendrocyte death.

    Directory of Open Access Journals (Sweden)

    Amalia Trousson

    Full Text Available BACKGROUND: Oxysterols are oxidized forms of cholesterol. They have been shown to be implicated in cholesterol turnover, inflammation and in neurodegenerative diseases such as Alzheimer's disease and multiple sclerosis. Glial cells are targets of oxysterols: they inhibit astrocyte proliferation after brain injury, and we have previously shown that 25-hydroxycholesterol (25OH provokes oligodendrocyte apoptosis and stimulates the expression of sPLA2 type IIA (sPLA2-IIA, which has a protective effect. METHODOLOGY/PRINCIPAL FINDINGS: As glucocorticoids are well-known for their anti-inflammatory effects, our aim was to understand their direct effects on oxysterol-induced responses in oligodendrocytes (sPLA2-IIA stimulation and apoptosis. We demonstrate that the synthetic glucocorticoid dexamethasone (Dex abolishes the stimulation of sPLA2-IIA by 25-hydroxycholesterol (25-OH. This inhibition is mediated by the glucocorticoid receptor (GR, which decreases the expression of the oxysterol receptor Pregnane X Receptor (PXR and interferes with oxysterol signaling by recruiting a common limiting coactivator PGC1alpha. Consistent with the finding that sPLA2-IIA can partially protect oligodendrocytes against oxysterol-triggered apoptosis, we demonstrate here that the inhibition of sPLA2-IIA by Dex accelerates the apoptotic phenomenon, leading to a shift towards necrosis. We have shown by atomic force microscopy and electron microscopy that 25-OH and Dex alters oligodendrocyte shape and disorganizes the cytoplasm. CONCLUSIONS/SIGNIFICANCE: Our results provide a new understanding of the cross-talk between oxysterol and glucocorticoid signaling pathways and their respective roles in apoptosis and oligodendrocyte functions.

  5. Vascular risk factor burden correlates with cerebrovascular reactivity but not resting state coactivation in the default mode network.

    Science.gov (United States)

    Tchistiakova, Ekaterina; Crane, David E; Mikulis, David J; Anderson, Nicole D; Greenwood, Carol E; Black, Sandra E; MacIntosh, Bradley J

    2015-11-01

    White matter hyperintensities (WMH) are prevalent among older adults and are often associated with cognitive decline and increased risk of stroke and dementia. Vascular risk factors (VRFs) are linked to WMH, yet the impact of multiple VRFs on gray matter function is still unclear. The goal of this study was to test for associations between the number of VRFs and cerebrovascular reactivity (CVR) and resting state (RS) coactivation among individuals with WMH. Twenty-nine participants with suspected WMH were grouped based on the number of VRFs (subgroups: 0, 1, or ≥2). CVR and RS coactivation were measured with blood oxygenation level-dependent (BOLD) imaging on a 3T magnetic resonance imaging (MRI) system during hypercapnia and rest, respectively. Default-mode (DMN), sensory-motor, and medial-visual networks, generated using independent component analysis of RS-BOLD, were selected as networks of interest (NOIs). CVR-BOLD was analyzed using two methods: 1) a model-based approach using CO2 traces, and 2) a dual-regression (DR) approach using NOIs as spatial inputs. Average CVR and RS coactivations within NOIs were compared between VRF subgroups. A secondary analysis investigated the correlation between CVR and RS coactivation. VRF subgroup differences were detected using DR-based CVR in the DMN (F20,2  = 5.17, P = 0.015) but not the model-based CVR nor RS coactivation. DR-based CVR was correlated with RS coactivation in the DMN (r(2)  = 0.28, P = 0.006) but not the sensory-motor nor medial-visual NOIs. In individuals with WMH, CVR in the DMN was inversely associated with the number of VRFs and correlated with RS coactivation. © 2015 Wiley Periodicals, Inc.

  6. Mediator and p300/CBP-Steroid Receptor Coactivator Complexes Have Distinct Roles, but Function Synergistically, during Estrogen Receptor α-Dependent Transcription with Chromatin Templates

    OpenAIRE

    Acevedo, Mari Luz; Kraus, W. Lee

    2003-01-01

    Ligand-dependent transcriptional activation by nuclear receptors involves the recruitment of various coactivators to the promoters of hormone-regulated genes assembled into chromatin. Nuclear receptor coactivators include histone acetyltransferase complexes, such as p300/CBP-steroid receptor coactivator (SRC), as well as the multisubunit mediator complexes (“Mediator”), which may help recruit RNA polymerase II to the promoter. We have used a biochemical approach, including an in vitro chromat...

  7. Anti-interleukin-1 alpha autoantibodies in humans: Characterization, isotype distribution, and receptor-binding inhibition--higher frequency in Schnitzler's syndrome (urticaria and macroglobulinemia)

    International Nuclear Information System (INIS)

    Saurat, J.H.; Schifferli, J.; Steiger, G.; Dayer, J.M.; Didierjean, L.

    1991-01-01

    Since autoantibodies (Abs) to cytokines may modify their biologic activities, high-affinity binding factors for interleukin-1 alpha (IL-1 alpha BF) were characterized in human sera. IL-1 alpha BF was identified as IgG (1) by sucrose density-gradient centrifugation followed by immunodiffusion autoradiography, (2) by ligand-blotting method, (3) by ligand binding to affinity-immobilized serum IgG, and (4) by IgG affinity purification followed by sucrose density-gradient centrifugation. IL-1 alpha binding activity resided in the F(ab)2 fragment. The apparent equilibrium constant was in the range of IgG found after immunization with conventional antigens (i.e., 10(-9) to 10(-10) mol/L). Anti-IL-1 alpha IgG auto-Abs represented only an extremely small fraction of total IgG (less than 1/10(-5)). Some sera with IL-1 alpha BF and purified IgG thereof were able to inhibit by 96% to 98% the binding of human recombinant IL-1 alpha to its receptor on murine thymoma EL4-6.1 cells, whereas other sera did not. When 125I-labeled anti-IL-1 alpha IgG complexes were injected into rats, they prolonged the plasma half-life of 125I-labeled IL-1 alpha several fold and altered its tissue distribution. The predominant class was IgG (12/19), mainly IgG4 (9/19), but in five of the sera, anti-IL-1 alpha IgA was also detected. In a screening of 271 sera, IL-1 alpha BF was detected in 17/98 normal subjects and was not more frequent in several control groups of patients, except in patients with Schnitzler's syndrome (fever, chronic urticaria, bone pain, and monoclonal IgM paraprotein) (6/9; p less than 0.005). The pathologic significance of these auto-Abs remains to be determined

  8. Synergistic effect of interleukin 1 alpha on nontypeable Haemophilus influenzae-induced up-regulation of human beta-defensin 2 in middle ear epithelial cells

    Directory of Open Access Journals (Sweden)

    Park Raekil

    2006-01-01

    Full Text Available Abstract Background We recently showed that beta-defensins have antimicrobial activity against nontypeable Haemophilus influenzae (NTHi and that interleukin 1 alpha (IL-1 alpha up-regulates the transcription of beta-defensin 2 (DEFB4 according to new nomenclature of the Human Genome Organization in human middle ear epithelial cells via a Src-dependent Raf-MEK1/2-ERK signaling pathway. Based on these observations, we investigated if human middle ear epithelial cells could release IL-1 alpha upon exposure to a lysate of NTHi and if this cytokine could have a synergistic effect on beta-defensin 2 up-regulation by the bacterial components. Methods The studies described herein were carried out using epithelial cell lines as well as a murine model of acute otitis media (OM. Human cytokine macroarray analysis was performed to detect the released cytokines in response to NTHi exposure. Real time quantitative PCR was done to compare the induction of IL-1 alpha or beta-defensin 2 mRNAs and to identify the signaling pathways involved. Direct activation of the beta-defensin 2 promoter was monitored using a beta-defensin 2 promoter-Luciferase construct. An IL-1 alpha blocking antibody was used to demonstrate the direct involvement of this cytokine on DEFB4 induction. Results Middle ear epithelial cells released IL-1 alpha when stimulated by NTHi components and this cytokine acted in an autocrine/paracrine synergistic manner with NTHi to up-regulate beta-defensin 2. This synergistic effect of IL-1 alpha on NTHi-induced beta-defensin 2 up-regulation appeared to be mediated by the p38 MAP kinase pathway. Conclusion We demonstrate that IL-1 alpha is secreted by middle ear epithelial cells upon exposure to NTHi components and that it can synergistically act with certain of these molecules to up-regulate beta-defensin 2 via the p38 MAP kinase pathway.

  9. Tennis players show a lower coactivation of the elbow antagonist muscles during isokinetic exercises.

    Science.gov (United States)

    Bazzucchi, Ilenia; Riccio, Maria Elena; Felici, Francesco

    2008-10-01

    Previous studies have suggested that muscle coactivation could be reduced by a recurrent activity (training, daily activities). If this was correct, skilled athletes should show a specific muscle activation pattern with a low level of coactivation of muscles which are typically involved in their discipline. In particular, the aim of this study was to verify the hypothesis that the amount of antagonist activation of biceps brachii (BB) and triceps brachii (TB) is different between tennis players and non-players individuals during maximal isokinetic contractions. Ten young healthy men and eight male tennis players participated in the study. The surface electromyographic signals (sEMG) were recorded from the BB and TB muscles during three maximal voluntary isometric contractions (MVC) of elbow flexors and extensors and a set of three maximal elbow flexions and extensions at 15 degrees , 30 degrees , 60 degrees , 120 degrees , 180 degrees and 240 degrees /s. Normalized root mean square (RMS) of sEMG was calculated as an index of sEMG amplitude. Antagonist activation (%RMSmax) of TB was significantly lower in tennis players (from 14.0+/-7.9% at MVC to 16.3+/-8.9% at 240 degrees /s) with respect to non-players (from 27.7+/-19.7% at MVC to 38.7+/-17.6% at 240 degrees /s) at all angular velocities. Contrary to non-players, tennis players did not show any difference in antagonist activation between BB and TB muscles. Tennis players, with a constant practice in controlling forces around the elbow joint, learn how to reduce coactivation of muscles involved in the control of this joint. This has been shown by the lower antagonist muscular activity of triceps brachii muscle during isokinetic elbow flexion found in tennis players with respect to non-players.

  10. Regulation of Nampt expression by transcriptional coactivator NCOA6 in pancreatic β-cells

    International Nuclear Information System (INIS)

    Yoon, Jin; Lee, Kyung Jin; Oh, Gyun-Sik; Kim, Geun Hyang; Kim, Seung-Whan

    2017-01-01

    Nuclear receptor coactivator 6 (NCOA6) is a transcriptional coactivator and crucial for insulin secretion and glucose metabolism in pancreatic β-cells. However, the regulatory mechanism of β-cell function by NCOA6 is largely unknown. In this study, we found that the transcript levels of nicotinamide phosphoribosyltransferase (Nampt) were decreased in islets of NCOA6 +/− mice compared with NCOA6 +/+ mice. Moreover, NCOA6 overexpression increased the levels of Nampt transcripts in the mouse pancreatic β-cell line NIT-1. Promoter analyses showed that transcriptional activity of the Nampt promoter was stimulated by cooperation of sterol regulatory element binding protein-1c (SREBP-1c) and NCOA6. Additional studies using mutant promoters demonstrated that SREBP-1c activates Nampt promoter through the sterol regulatory element (SRE), but not through the E-box. Using chromatin immunoprecipitation assay, NCOA6 was also shown to be directly recruited to the SRE region of the Nampt promoter. Furthermore, treatment with nicotinamide mononucleotide (NMN), a product of the Nampt reaction and a key NAD + intermediate, ameliorates glucose-stimulated insulin secretion from NCOA6 +/− islets. These results suggest that NCOA6 stimulates insulin secretion, at least partially, by modulating Nampt expression in pancreatic β-cells. - Highlights: • Nampt transcription in β-cells is activated by SREBP-1c through the SRE element. • NCOA6 enhances the transcriptional activity of SREBP-1c in the Nampt promoter. • Defective insulin secretion of NCOA6 +/− islets is recovered by NMN treatment. • NCOA6 is reportedly the first coactivator involved in Nampt expression.

  11. [Characteristics of sublingual vein and expressions of vascular endothelial growth factor and hypoxia-inducible factor 1alpha proteins in sublingual tissues of Beagle dogs with portal hypertension].

    Science.gov (United States)

    Li, Bai-yu; Wang, Li-na; Yue, Xiao-qiang; Li, Bai

    2009-05-01

    To observe sublingual vein characteristics and the expressions of vascular endothelial growth factor (VEGF) and hypoxia-inducible factor 1alpha (HIF-1alpha) proteins in sublingual tissues of Beagle dogs with cirrhotic portal hypertension. Twelve Beagle dogs were randomly divided into normal control group and cirrhotic portal hypertension group. There were 6 dogs in each group. A canine model of cirrhosis portal hypertension was established by injecting dimethylnitrosamine (DMN) into portal vein once a week for 7 weeks. The characteristics of sublingual vein were observed. Portal venous pressure was measured by using bioelectric recording techniques. The expressions of VEGF and HIF-1alpha proteins in sublingual vein were detected by immunohistochemical method. The shape and color of sublingual vein in beagle dogs in the cirrhotic portal hypertension group changed obviously as compared with the normal control group. Immunohistochemical results showed that there were almost no expressions of VEGF and HIF-1alpha proteins in sublingual tissues in the normal control group; however, the expressions of VEGF and HIF-1alpha proteins in sublingual tissues in the cirrhotic portal hypertension group significantly increased. Changes of portal pressure may lead to the formation of the abnormal sublingual vein by increasing the expressions of VEGF and HIF-1alpha proteins in sublingual tissues in Beagle dogs with portal hypertension.

  12. Endothelial monocyte activating polypeptide-II modulates endothelial cell responses by degrading hypoxia-inducible factor-1alpha through interaction with PSMA7, a component of the proteasome

    Energy Technology Data Exchange (ETDEWEB)

    Tandle, Anita T. [Tumor Angiogenesis Section, Surgery Branch, Center for Cancer Research, National Cancer Institute, Bethesda, Maryland 20892 (United States); Calvani, Maura; Uranchimeg, Badarch [DTP-Tumor Hypoxia Laboratory, SAIC Frederick, Inc., National Cancer Institute, Frederick, Maryland 21702 (United States); Zahavi, David [Tumor Angiogenesis Section, Surgery Branch, Center for Cancer Research, National Cancer Institute, Bethesda, Maryland 20892 (United States); Melillo, Giovanni [DTP-Tumor Hypoxia Laboratory, SAIC Frederick, Inc., National Cancer Institute, Frederick, Maryland 21702 (United States); Libutti, Steven K., E-mail: slibutti@montefiore.org [Department of Surgery, Montefiore-Einstein Center for Cancer Care, Albert Einstein College of Medicine, Greene Medical Arts Pavilion, 4th Floor 3400, Bainbridge Avenue, Bronx, New York 10467 (United States)

    2009-07-01

    The majority of human tumors are angiogenesis dependent. Understanding the specific mechanisms that contribute to angiogenesis may offer the best approach to develop therapies to inhibit angiogenesis in cancer. Endothelial monocyte activating polypeptide-II (EMAP-II) is an anti-angiogenic cytokine with potent effects on endothelial cells (ECs). It inhibits EC proliferation and cord formation, and it suppresses primary and metastatic tumor growth in-vivo. However, very little is known about the molecular mechanisms behind the anti-angiogenic activity of EMAP-II. In the present study, we explored the molecular mechanism behind the anti-angiogenic activity exerted by this protein on ECs. Our results demonstrate that EMAP-II binds to the cell surface {alpha}5{beta}1 integrin receptor. The cell surface binding of EMAP-II results in its internalization into the cytoplasmic compartment where it interacts with its cytoplasmic partner PSMA7, a component of the proteasome degradation pathway. This interaction increases hypoxia-inducible factor 1-alpha (HIF-1{alpha}) degradation under hypoxic conditions. The degradation results in the inhibition of HIF-1{alpha} mediated transcriptional activity as well as HIF-1{alpha} mediated angiogenic sprouting of ECs. HIF-1{alpha} plays a critical role in angiogenesis by activating a variety of angiogenic growth factors. Our results suggest that one of the major anti-angiogenic functions of EMAP-II is exerted through its inhibition of the HIF-1{alpha} activities.

  13. Asymmetry and Thigh Muscle Coactivity in Fatigued Anterior Cruciate Ligament-Reconstructed Elite Skiers

    DEFF Research Database (Denmark)

    Jordan, Matthew J; Aagaard, Per; Herzog, Walter

    2017-01-01

    PURPOSE: The acute effects of fatigue on functional interlimb asymmetry and quadriceps/hamstring muscle activity levels, including preparatory coactivation during squat jump takeoff and landing, were evaluated in elite alpine ski racers with/without anterior cruciate ligament reconstruction (ACLR......). METHODS: Twenty-two elite ski racers (ACLR, n = 11; control, n = 11) performed an 80-s repeated squat jump test (jump test) on a dual force plate system with simultaneous EMG recordings in vastus lateralis, vastus medialis, semitendinosus, and biceps femoris. Asymmetry index (AI) and jump height of body...

  14. Task vs. rest-different network configurations between the coactivation and the resting-state brain networks.

    Science.gov (United States)

    Di, Xin; Gohel, Suril; Kim, Eun H; Biswal, Bharat B

    2013-01-01

    There is a growing interest in studies of human brain networks using resting-state functional magnetic resonance imaging (fMRI). However, it is unclear whether and how brain networks measured during the resting-state exhibit comparable properties to brain networks during task performance. In the present study, we investigated meta-analytic coactivation patterns among brain regions based upon published neuroimaging studies, and compared the coactivation network configurations with those in the resting-state network. The strength of resting-state functional connectivity between two regions were strongly correlated with the coactivation strength. However, the coactivation network showed greater global efficiency, smaller mean clustering coefficient, and lower modularity compared with the resting-state network, which suggest a more efficient global information transmission and between system integrations during task performing. Hub shifts were also observed within the thalamus and the left inferior temporal cortex. The thalamus and the left inferior temporal cortex exhibited higher and lower degrees, respectively in the coactivation network compared with the resting-state network. These results shed light regarding the reconfiguration of the brain networks between task and resting-state conditions, and highlight the role of the thalamus in change of network configurations in task vs. rest.

  15. Task vs. rest—different network configurations between the coactivation and the resting-state brain networks

    Science.gov (United States)

    Di, Xin; Gohel, Suril; Kim, Eun H.; Biswal, Bharat B.

    2013-01-01

    There is a growing interest in studies of human brain networks using resting-state functional magnetic resonance imaging (fMRI). However, it is unclear whether and how brain networks measured during the resting-state exhibit comparable properties to brain networks during task performance. In the present study, we investigated meta-analytic coactivation patterns among brain regions based upon published neuroimaging studies, and compared the coactivation network configurations with those in the resting-state network. The strength of resting-state functional connectivity between two regions were strongly correlated with the coactivation strength. However, the coactivation network showed greater global efficiency, smaller mean clustering coefficient, and lower modularity compared with the resting-state network, which suggest a more efficient global information transmission and between system integrations during task performing. Hub shifts were also observed within the thalamus and the left inferior temporal cortex. The thalamus and the left inferior temporal cortex exhibited higher and lower degrees, respectively in the coactivation network compared with the resting-state network. These results shed light regarding the reconfiguration of the brain networks between task and resting-state conditions, and highlight the role of the thalamus in change of network configurations in task vs. rest. PMID:24062654

  16. Ablation of steroid receptor coactivator-3 resembles the human CACT metabolic myopathy.

    Science.gov (United States)

    York, Brian; Reineke, Erin L; Sagen, Jørn V; Nikolai, Bryan C; Zhou, Suoling; Louet, Jean-Francois; Chopra, Atul R; Chen, Xian; Reed, Graham; Noebels, Jeffrey; Adesina, Adekunle M; Yu, Hui; Wong, Lee-Jun C; Tsimelzon, Anna; Hilsenbeck, Susan; Stevens, Robert D; Wenner, Brett R; Ilkayeva, Olga; Xu, Jianming; Newgard, Christopher B; O'Malley, Bert W

    2012-05-02

    Oxidation of lipid substrates is essential for survival in fasting and other catabolic conditions, sparing glucose for the brain and other glucose-dependent tissues. Here we show Steroid Receptor Coactivator-3 (SRC-3) plays a central role in long chain fatty acid metabolism by directly regulating carnitine/acyl-carnitine translocase (CACT) gene expression. Genetic deficiency of CACT in humans is accompanied by a constellation of metabolic and toxicity phenotypes including hypoketonemia, hypoglycemia, hyperammonemia, and impaired neurologic, cardiac and skeletal muscle performance, each of which is apparent in mice lacking SRC-3 expression. Consistent with human cases of CACT deficiency, dietary rescue with short chain fatty acids drastically attenuates the clinical hallmarks of the disease in mice devoid of SRC-3. Collectively, our results position SRC-3 as a key regulator of β-oxidation. Moreover, these findings allow us to consider platform coactivators such as the SRCs as potential contributors to syndromes such as CACT deficiency, previously considered as monogenic. Copyright © 2012 Elsevier Inc. All rights reserved.

  17. Implicit co-activation of American Sign Language in deaf readers: An ERP study.

    Science.gov (United States)

    Meade, Gabriela; Midgley, Katherine J; Sevcikova Sehyr, Zed; Holcomb, Phillip J; Emmorey, Karen

    2017-07-01

    In an implicit phonological priming paradigm, deaf bimodal bilinguals made semantic relatedness decisions for pairs of English words. Half of the semantically unrelated pairs had phonologically related translations in American Sign Language (ASL). As in previous studies with unimodal bilinguals, targets in pairs with phonologically related translations elicited smaller negativities than targets in pairs with phonologically unrelated translations within the N400 window. This suggests that the same lexicosemantic mechanism underlies implicit co-activation of a non-target language, irrespective of language modality. In contrast to unimodal bilingual studies that find no behavioral effects, we observed phonological interference, indicating that bimodal bilinguals may not suppress the non-target language as robustly. Further, there was a subset of bilinguals who were aware of the ASL manipulation (determined by debrief), and they exhibited an effect of ASL phonology in a later time window (700-900ms). Overall, these results indicate modality-independent language co-activation that persists longer for bimodal bilinguals. Copyright © 2017 Elsevier Inc. All rights reserved.

  18. Transcriptional activity of Pax3 is co-activated by TAZ

    International Nuclear Information System (INIS)

    Murakami, Masao; Tominaga, Junji; Makita, Ryosuke; Uchijima, Yasunobu; Kurihara, Yukiko; Nakagawa, Osamu; Asano, Tomoichiro; Kurihara, Hiroki

    2006-01-01

    Pax3 is a transcription factor which functions in embryonic development and human diseases. In a yeast two-hybrid screen with full-length Pax3 as bait, we isolated a clone encoding transcriptional co-activator with PDZ-binding motif (TAZ) from an E10.5 mouse embryo cDNA library. Co-immunoprecipitation and nuclear co-localization of TAZ with Pax3 suggest that their association is functionally relevant. In situ hybridization revealed TAZ and Pax3 expression to partially overlap in the paraxial mesoderm, limb buds, and the neural tube. In C2C12 myoblast cells and NIH3T3 cells, TAZ enhanced the transcriptional activity of Pax3 on artificial and microphthalmia-associated transcription factor promoter-luciferase constructs, suggesting that TAZ can function as a co-activator of Pax3. Functional interaction between Pax3 and TAZ may provide a clue to clarifying the mechanism by which Pax3 serves as a transcriptional activator during embryogenesis

  19. Reverting doxorubicin resistance in colon cancer by targeting a key signaling protein, steroid receptor coactivator.

    Science.gov (United States)

    Xiong, Sang; Xiao, Gong-Wei

    2018-04-01

    Although there have been notable improvements in treatments against cancer, further research is required. In colon cancer, nearly all patients eventually experience drug resistance and stop responding to the approved drugs, making treatment difficult. Steroid receptor coactivator (SRC) is an oncogenic nuclear receptor coactivator that serves an important role in drug resistance. The present study generated a doxorubicin-resistant colon cancer cell line, in which the upregulation/activation of SRC was responsible for drug resistance, which in turn activated AKT. Overexpression of receptor tyrosine kinase-like epidermal growth factor receptor and insulin-like growth factor 1 receptor also induced SRC expression. It was observed that doxorubicin resistance in colon cancer also induced epithelial to mesenchymal transition, a decrease in expression of epithelial marker E-cadherin and an increase in the expression of mesenchymal markers, including N-cadherin and vimentin. Additionally, the present study indicated that SRC acts as a common signaling node, and inhibiting SRC in combination with doxorubicin treatment in doxorubicin-resistant cells aids in reversing the resistance. Thus, the present study suggests that activation of SRC is responsible for doxorubicin resistance in colon cancer. However, further research is required to understand the complete mechanism of how drug resistance occurs and how it may be tackled to treat patients.

  20. The impact of language co-activation on L1 and L2 speech fluency.

    Science.gov (United States)

    Bergmann, Christopher; Sprenger, Simone A; Schmid, Monika S

    2015-10-01

    Fluent speech depends on the availability of well-established linguistic knowledge and routines for speech planning and articulation. A lack of speech fluency in late second-language (L2) learners may point to a deficiency of these representations, due to incomplete acquisition. Experiments on bilingual language processing have shown, however, that there are strong reasons to believe that multilingual speakers experience co-activation of the languages they speak. We have studied to what degree language co-activation affects fluency in the speech of bilinguals, comparing a monolingual German control group with two bilingual groups: 1) first-language (L1) attriters, who have fully acquired German before emigrating to an L2 English environment, and 2) immersed L2 learners of German (L1: English). We have analysed the temporal fluency and the incidence of disfluency markers (pauses, repetitions and self-corrections) in spontaneous film retellings. Our findings show that learners to speak more slowly than controls and attriters. Also, on each count, the speech of at least one of the bilingual groups contains more disfluency markers than the retellings of the control group. Generally speaking, both bilingual groups-learners and attriters-are equally (dis)fluent and significantly more disfluent than the monolingual speakers. Given that the L1 attriters are unaffected by incomplete acquisition, we interpret these findings as evidence for language competition during speech production. Copyright © 2015. Published by Elsevier B.V.

  1. Multiple functions and essential roles of nuclear receptor coactivators of bHLH-PAS family.

    Science.gov (United States)

    Pecenova, L; Farkas, Robert

    2016-07-01

    Classical non-peptide hormones, such as steroids, retinoids, thyroid hormones, vitamin D3 and their derivatives including prostaglandins, benzoates, oxysterols, and bile acids, are collectively designated as small lipophilic ligands, acting via binding to the nuclear receptors (NRs). The NRs form a large superfamily of transcription factors that participate virtually in every key biological process. They control various aspects of animal development, fertility, gametogenesis, and numerous metabolic pathways, and can be misregulated in many types of cancers. Their enormous functional plasticity, as transcription factors, relates in part to NR-mediated interactions with plethora of coregulatory proteins upon ligand binding to their ligand binding domains (LBD), or following covalent modification. Here, we review some general views of a specific group of NR coregulators, so-called nuclear receptor coactivators (NRCs) or steroid receptor coactivators (SRCs) and highlight some of their unique functions/roles, which are less extensively mentioned and discussed in other reviews. We also try to pinpoint few neglected moments in the cooperative action of SRCs, which may also indicate their variable roles in the hormone-independent signaling pathways.

  2. MicroRNA-195 induced apoptosis in hypoxic chondrocytes by targeting hypoxia-inducible factor 1 alpha.

    Science.gov (United States)

    Bai, R; Zhao, A-Q; Zhao, Z-Q; Liu, W-L; Jian, D-M

    2015-02-01

    The chondrocytes, the resident cells of cartilage, are maintained and take effects in the whole life upon chronic hypoxic exposure, which hypoxia-inducible factor 1 alpha (HIF-1α) play pivotal roles in response to. Dysregulation of some microRNA (miRNAs) have also been identified to be involved in hypoxia-related physiologic and pathophysiologic responses in some tissues or cell lines. However, the mechanism of miRNAs reponse to hypoxia remain largely unknown in chondrocytes, including the microRNA-195 (miR-195). AIM To investigate the effects of microRNAs (miRNAs) and hypoxia-inducible factor 1 alpha (HIF-1α) on chondrocytes in physiologic environment. We compared the expression of miR-195 and HIF-1α mRNA on hypoxia with that on normoxia in ATDC 5 cells by qRT-PCR. Further experiments was performed to confirmed the relationships of miR-195 and HIF-1α by bioinformatics analysis and dual reporter gene assay. we also assessed the effect of miR-195 on apoptosis in hypoxic ATDC 5 cells by transfect with miR-195 mimics. It was found the downregulated miR-195 and upregulated HIF-1α were present in hypoxic ATDC 5 cells. miR-195 negatively regulated HIF-1α by targeting its 3'-untranslated region. Moreover, the founding indicated miR-195 greatly increased apoptosis and downregulated HIF-1α mRNA occurred simultaneously in hypoxic chondrocytes. We concluded that miR-195 induced apoptosis in hypoxic chondrocytes by directly targeting HIF-1α.

  3. Kinetic Stability May Determine the Interaction Dynamics of the Bifunctional Protein DCoH1, the Dimerization Cofactor of the Transcription Factor HNF-1[alpha

    Energy Technology Data Exchange (ETDEWEB)

    Rho, H.; Jones, C.N.; Rose, R.B. (NCSU)

    2010-12-07

    The two disparate functions of DCoH1 (dimerization cofactor of HNF-1)/PCD (pterin-4a-carbinolamine dehydratase) are associated with a change in oligomeric state. DCoH dimers enhance the activity of the diabetes-associated transcription factor HNF-1{alpha} (hepatocyte nuclear factor-1{alpha}), while the PCD activity of DCoH1 homotetramers aids in aromatic amino acid metabolism. These complexes compete for the same interface of the DCoH dimer. Formation of the DCoH1/HNF-1{alpha} complex requires cofolding. The homotetramer of the DCoH1 paralogue, DCoH2, interacts with HNF-1{alpha} through simple mixing. To further investigate regulation of DCoH/HNF-1{alpha} complex formation, we measured the stability of the DCoH1 homotetramer through unfolding studies by intrinsic tryptophan fluorescence. DCoH2 unfolding is reversible. Surprisingly, the DCoH1 homotetramer is resistant to guanidine unfolding but refolds at a much lower guanidine concentration. We show that a point mutation at the DCoH1 tetramer interface, Thr 51 Ser, overcomes the dissociation barrier of the homotetramer and increases the interaction with HNF-1{alpha}. The 1.8 {angstrom} resolution crystal structure of DCoH1 T51S shows the presence of an ordered water molecule at the tetramer interface, as in DCoH2, which may destabilize the homotetramer. The equilibrium unfolding data were fit to a two-state model with no apparent intermediate. Folding intermediates were detectable by size exclusion chromatography. For wild-type DCoH1 the intermediates changed with time, suggesting a kinetic origin for the unfolding barrier of the homotetramer. We propose an unfolding pathway in which the tetramer unfolds slowly, but the dimer folds reversibly. Implications for regulation of DCoH1/HNF-1{alpha} complex formation are discussed.

  4. Clinical differences between patients with MODY-3, MODY-2 and type 2 diabetes mellitus with I27L polymorphism in the HNF1alpha gene.

    Science.gov (United States)

    Pinés Corrales, Pedro José; López Garrido, María P; Aznar Rodríguez, Silvia; Louhibi Rubio, Lynda; López Jiménez, Luz M; Lamas Oliveira, Cristina; Alfaro Martínez, Jose J; Lozano García, Jose J; Hernández López, Antonio; Requejo Castillo, Ramón; Escribano Martínez, Julio; Botella Romero, Francisco

    2010-01-01

    The aim of our study was to describe and evaluate the clinical and metabolic characteristics of patients with MODY-3, MODY-2 or type 2 diabetes who presented I27L polymorphism in the HNF1alpha gene. The study included 31 previously diagnosed subjects under follow-up for MODY-3 (10 subjects from 5 families), MODY-2 (15 subjects from 9 families), or type 2 diabetes (6 subjects) with I27L polymorphism in the HNF1alpha gene. The demographic, clinical, metabolic, and genetic characteristics of all patients were analyzed. No differences were observed in distribution according to sex, age of onset, or form of diagnosis. All patients with MODY-2 or MODY-3 had a family history of diabetes. In contrast, 33.3% of patients with type 2 diabetes mellitus and I27L polymorphism in the HNF1alpha gene had no family history of diabetes (p MODY-3 patients, but not required by 100% of MODY-2 patients or 16.7% of patients with type 2 diabetes mellitus and I27L polymorphism in the HNF1alpha gene (p MODY-2, MODY-3 or type 2 diabetes of atypical characteristics, in this case patients who present I27L polymorphism in the HNF1alpha gene. Copyright 2010 Sociedad Española de Endocrinología y Nutrición. Published by Elsevier Espana. All rights reserved.

  5. Induction of experimental autoimmune encephalomyelitis in C57BL/6 mice deficient in either the chemokine macrophage inflammatory protein-1alpha or its CCR5 receptor

    DEFF Research Database (Denmark)

    Tran, E H; Kuziel, W A; Owens, T

    2000-01-01

    -type mice in Th1 cytokine gene expression, the kinetics and severity of disease, and infiltration of the central nervous system by lymphocytes, macrophages and granulocytes. RNase protection assays showed comparable accumulation of mRNA for the chemokines interferon-inducible protein-10, RANTES, macrophage...... and its CCR5 receptor in the induction of EAE by immunizing C57BL / 6 mice deficient in either MIP-1alpha or CCR5 with myelin oligodendrocyte glycoprotein (MOG). We found that MIP-1alpha-deficient mice were fully susceptible to MOG-induced EAE. These knockout animals were indistinguishable from wild...... chemoattractant protein-1, MIP-1beta, MIP-2, lymphotactin and T cell activation gene-3 during the course of the disease. CCR5-deficient mice were also susceptible to disease induction by MOG. The dispensability of MIP-1alpha and CCR5 for MOG-induced EAE in C57BL / 6 mice supports the idea that differential...

  6. HSP72 protects cells from ER stress-induced apoptosis via enhancement of IRE1alpha-XBP1 signaling through a physical interaction.

    LENUS (Irish Health Repository)

    Gupta, Sanjeev

    2010-01-01

    Endoplasmic reticulum (ER) stress is a feature of secretory cells and of many diseases including cancer, neurodegeneration, and diabetes. Adaptation to ER stress depends on the activation of a signal transduction pathway known as the unfolded protein response (UPR). Enhanced expression of Hsp72 has been shown to reduce tissue injury in response to stress stimuli and improve cell survival in experimental models of stroke, sepsis, renal failure, and myocardial ischemia. Hsp72 inhibits several features of the intrinsic apoptotic pathway. However, the molecular mechanisms by which Hsp72 expression inhibits ER stress-induced apoptosis are not clearly understood. Here we show that Hsp72 enhances cell survival under ER stress conditions. The UPR signals through the sensor IRE1alpha, which controls the splicing of the mRNA encoding the transcription factor XBP1. We show that Hsp72 enhances XBP1 mRNA splicing and expression of its target genes, associated with attenuated apoptosis under ER stress conditions. Inhibition of XBP1 mRNA splicing either by dominant negative IRE1alpha or by knocking down XBP1 specifically abrogated the inhibition of ER stress-induced apoptosis by Hsp72. Regulation of the UPR was associated with the formation of a stable protein complex between Hsp72 and the cytosolic domain of IRE1alpha. Finally, Hsp72 enhanced the RNase activity of recombinant IRE1alpha in vitro, suggesting a direct regulation. Our data show that binding of Hsp72 to IRE1alpha enhances IRE1alpha\\/XBP1 signaling at the ER and inhibits ER stress-induced apoptosis. These results provide a physical connection between cytosolic chaperones and the ER stress response.

  7. HSP72 protects cells from ER stress-induced apoptosis via enhancement of IRE1alpha-XBP1 signaling through a physical interaction.

    Directory of Open Access Journals (Sweden)

    Sanjeev Gupta

    2010-07-01

    Full Text Available Endoplasmic reticulum (ER stress is a feature of secretory cells and of many diseases including cancer, neurodegeneration, and diabetes. Adaptation to ER stress depends on the activation of a signal transduction pathway known as the unfolded protein response (UPR. Enhanced expression of Hsp72 has been shown to reduce tissue injury in response to stress stimuli and improve cell survival in experimental models of stroke, sepsis, renal failure, and myocardial ischemia. Hsp72 inhibits several features of the intrinsic apoptotic pathway. However, the molecular mechanisms by which Hsp72 expression inhibits ER stress-induced apoptosis are not clearly understood. Here we show that Hsp72 enhances cell survival under ER stress conditions. The UPR signals through the sensor IRE1alpha, which controls the splicing of the mRNA encoding the transcription factor XBP1. We show that Hsp72 enhances XBP1 mRNA splicing and expression of its target genes, associated with attenuated apoptosis under ER stress conditions. Inhibition of XBP1 mRNA splicing either by dominant negative IRE1alpha or by knocking down XBP1 specifically abrogated the inhibition of ER stress-induced apoptosis by Hsp72. Regulation of the UPR was associated with the formation of a stable protein complex between Hsp72 and the cytosolic domain of IRE1alpha. Finally, Hsp72 enhanced the RNase activity of recombinant IRE1alpha in vitro, suggesting a direct regulation. Our data show that binding of Hsp72 to IRE1alpha enhances IRE1alpha/XBP1 signaling at the ER and inhibits ER stress-induced apoptosis. These results provide a physical connection between cytosolic chaperones and the ER stress response.

  8. Perturbation of estrogen receptor α localization with synthetic nona-arginine LXXLL-peptide coactivator binding inhibitors

    NARCIS (Netherlands)

    Carraz, M.; Zwart, W.; Phan, T.; Michalides, R.; Brunsveld, L.

    2009-01-01

    The interaction of estrogen receptor a (ERa) with the consensus LXXLL motifs of transcriptional coactivators provides an entry for functional ERa inhibition. Here, synthetic cell-permeable LXXLL peptide probes are brought forward that allow evaluation of the interaction of specific recognition

  9. Synthesis and biological evaluation of guanylhydrazone coactivator binding inhibitors for the estrogen receptor.

    Science.gov (United States)

    LaFrate, Andrew L; Gunther, Jillian R; Carlson, Kathryn E; Katzenellenbogen, John A

    2008-12-01

    Most patients with hormone-responsive breast cancer eventually develop resistance to traditional antiestrogens such as tamoxifen, and this has become a major obstacle in their treatment. We prepared and characterized the activity of a series of 16 guanylhydrazone small molecules that are designed to block estrogen receptor (ER) activity through a non-traditional mechanism, by directly interfering with coactivator binding to agonist-liganded ER. The inhibitory activity of these compounds was determined in cell-based transcription assays using ER-responsive reporter gene and mammalian two-hybrid assays. Several of the compounds gave IC(50) values in the low micromolar range. Two secondary assays were used to confirm that these compounds were acting through the proposed non-traditional mode of estrogen inhibitory action and not as conventional antagonists at the ligand binding site.

  10. The metazoan Mediator co-activator complex as an integrative hub for transcriptional regulation.

    Science.gov (United States)

    Malik, Sohail; Roeder, Robert G

    2010-11-01

    The Mediator is an evolutionarily conserved, multiprotein complex that is a key regulator of protein-coding genes. In metazoan cells, multiple pathways that are responsible for homeostasis, cell growth and differentiation converge on the Mediator through transcriptional activators and repressors that target one or more of the almost 30 subunits of this complex. Besides interacting directly with RNA polymerase II, Mediator has multiple functions and can interact with and coordinate the action of numerous other co-activators and co-repressors, including those acting at the level of chromatin. These interactions ultimately allow the Mediator to deliver outputs that range from maximal activation of genes to modulation of basal transcription to long-term epigenetic silencing.

  11. Hepatic Insulin Resistance Following Chronic Activation of the CREB Coactivator CRTC2

    DEFF Research Database (Denmark)

    Hogan, Meghan F; Ravnskjaer, Kim; Matsumura, Shigenobu

    2015-01-01

    and dephosphorylation of the cAMP regulated CREB coactivators CRTC2 and CRTC3. In parallel, decreases in circulating insulin also increase gluconeogenic gene expression via the de-phosphorylation and activation of the forkhead transcription factor FOXO1. Hepatic gluconeogenesis is increased in insulin resistance where...... increased gluconeogenic gene expression under fasting as well as feeding conditions. Circulating glucose concentrations were constitutively elevated in CRTC2S171,275A expressing mice, leading to compensatory increases in circulating insulin concentrations that enhance FOXO1 phosphorylation. Despite...... accompanying decreases in FOXO1 activity, hepatic gluconeogenic gene expression remained elevated in CRTC2S171,275A mice demonstrating that chronic increases in CRTC2 activity in the liver are indeed sufficient to promote hepatic insulin resistance and to disrupt glucose homeostasis....

  12. General applicability of chicken egg yolk antibodies: the performance of IgY immunoglobulins raised against the hypoxia-inducible factor 1alpha

    OpenAIRE

    Camenisch, G; Tini, M; Chilov, D; Kvietikova, I; Srinivas, V; Caro, J; Spielmann, P; Wenger, R H; Gassmann, M

    1999-01-01

    Avian embryos and neonates acquire passive immunity by transferring maternal immunoglobulins from serum to egg yolk. Despite being a convenient source of antibodies, egg yolk immunoglobulins (IgY) from immunized hens have so far received scant attention in research. Here we report the generation and rapid isolation of IgY from the egg yolk of hens immunized against the alpha subunit of the human hypoxia-inducible factor 1 (HIF-1alpha). Anti-HIF-1alpha IgY antibodies were affinity purified and...

  13. Sertad1 encodes a novel transcriptional co-activator of SMAD1 in mouse embryonic hearts

    Energy Technology Data Exchange (ETDEWEB)

    Peng, Yin [Department of Genetics, The University of Alabama at Birmingham, Birmingham, AL 35294 (United States); Zhao, Shaomin [Department of Genetics, The University of Alabama at Birmingham, Birmingham, AL 35294 (United States); School of Traditional Chinese Medicine, Capital Medical University, Beijing 100069 (China); Song, Langying [Department of Genetics, The University of Alabama at Birmingham, Birmingham, AL 35294 (United States); Wang, Manyuan [School of Traditional Chinese Medicine, Capital Medical University, Beijing 100069 (China); Jiao, Kai, E-mail: kjiao@uab.edu [Department of Genetics, The University of Alabama at Birmingham, Birmingham, AL 35294 (United States)

    2013-11-29

    Highlights: •SERTAD1 interacts with SMAD1. •Sertad1 is expressed in mouse embryonic hearts. •SERTAD1 is localized in both cytoplasm and nucleus of cardiomyocytes. •SERTAD1 enhances expression of BMP target cardiogenic genes as a SMAD1 co-activator. -- Abstract: Despite considerable advances in surgical repairing procedures, congenital heart diseases (CHDs) remain the leading noninfectious cause of infant morbidity and mortality. Understanding the molecular/genetic mechanisms underlying normal cardiogenesis will provide essential information for the development of novel diagnostic and therapeutic strategies against CHDs. BMP signaling plays complex roles in multiple cardiogenic processes in mammals. SMAD1 is a canonical nuclear mediator of BMP signaling, the activity of which is critically regulated through its interaction partners. We screened a mouse embryonic heart yeast two-hybrid library using Smad1 as bait and identified SERTAD1 as a novel interaction partner of SMAD1. SERTAD1 contains multiple potential functional domains, including two partially overlapping transactivation domains at the C terminus. The SERTAD1-SMAD1 interaction in vitro and in mammalian cells was further confirmed through biochemical assays. The expression of Sertad1 in developing hearts was demonstrated using RT-PCR, western blotting and in situ hybridization analyses. We also showed that SERTAD1 was localized in both the cytoplasm and nucleus of immortalized cardiomyocytes and primary embryonic cardiomyocyte cultures. The overexpression of SERTAD1 in cardiomyocytes not only enhanced the activity of two BMP reporters in a dose-dependent manner but also increased the expression of several known BMP/SMAD regulatory targets. Therefore, these data suggest that SERTAD1 acts as a SMAD1 transcriptional co-activator to promote the expression of BMP target genes during mouse cardiogenesis.

  14. Co-activated yet disconnected-Neural correlates of eye closures when trying to stay awake.

    Science.gov (United States)

    Ong, Ju Lynn; Kong, Danyang; Chia, Tiffany T Y; Tandi, Jesisca; Thomas Yeo, B T; Chee, Michael W L

    2015-09-01

    Spontaneous eye-closures that herald sleep onset become more frequent when we are sleep deprived. Although these are typically associated with decreased responsiveness to external stimuli, it is less clear what occurs in the brain at these transitions to drowsiness and light sleep. To investigate this, task-free fMRI of sleep-deprived participants was acquired. BOLD activity associated with periods of spontaneously occurring eye closures were marked and analyzed. We observed concurrent and extensive hypnagogic co-activation of the extrastriate visual, auditory, and somatosensory cortices as well as the default mode network, consistent with internal sensory activity without external stimulation. Co-activation of fronto-parietal areas known to mediate attentional control could correspond with participants resisting sleep or additional engagement of mental imagery. This constellation of signal changes differed from those elicited by cued eye closures of similar duration and distribution in the same, rested participants. They also differ from signal changes associated with mind-wandering and consolidated light sleep. Concurrent with the observed event-related changes, eye closures elicited additional reduction in functional connectivity within nodes of the DMN and DAN, superposed on already reduced connectivity associated with sleep deprivation. There was concurrent deactivation of the thalamus during eye-closure during the sleep-deprived state but almost similar changes occurred in the well-rested state that may also be relevant. These findings highlight the dynamic shifts in brain activity and connectivity at border between wakefulness and sleep. Copyright © 2015. Published by Elsevier Inc.

  15. Effect of posterior cruciate ligament creep on muscular co-activation around knee: a pilot study.

    Science.gov (United States)

    Cheng, Xiangrong; Zhang, Tailai; Shan, Xinhai; Wang, Jingyuan

    2014-04-01

    The effect of posterior cruciate ligament (PCL) on muscle co-activation (MCO) is not known though MCO has been extensively studied. The purpose of the study was to investigate the effect of PCL creep on MCO and on joint moment around the knee. Twelve males and twelve females volunteered for this study. PCL creep was estimated via tibial posterior displacement which was elicited by a 20kg dumbbell hanged on horizontal shank near patella for 10min. Electromyography activity from both rectus femoris and biceps femoris as well as muscle strength on the right thigh was recorded synchronically during knee isokinetic flexion-extension performance in speed of 60deg/s as well as 120deg/s on a dynamometer before and after PCL creep. A one-way ANOVA with repeated measures was used to evaluate the effect of creep, gender and speed. The results showed that significant tibial posterior displacement was found (p=0.01) in both male and female groups. No significant increase of joint moment was found in flexion as well as in extension phase in both female and male groups. There was a significant effect of speed (p=0.036) on joint moment in extension phase. Co-activation index (CI) decreased significantly (p=0.049) in extension phase with a significant effect of gender (p⩽0.001). It was concluded that creep developed in PCL due to static posterior load on the proximal tibia could significantly elicit the increase of the activation of agonist muscles but with no compensation from the antagonist in flexion as well as in extension phase. The creep significantly elicited the decrease of the antagonist-agonist CI in extension phase. MCO in females was reduced significantly in extension phase. It was suggested that PCL creep might be one of risk factors to the knee injury in sports activity. Copyright © 2014. Published by Elsevier Ltd.

  16. Mediator subunit MED1 is a T3-dependent and T3-independent coactivator on the thyrotropin β gene promoter

    Energy Technology Data Exchange (ETDEWEB)

    Matsui, Keiji; Oda, Kasumi; Mizuta, Shumpei; Ishino, Ruri; Urahama, Norinaga; Hasegawa, Natsumi [Laboratory of Hematology, Division of Medical Biophysics, Kobe University Graduate School of Health Sciences, 7-10-2 Tomogaoka, Suma-ku, Kobe 654-0142 (Japan); Roeder, Robert G. [Laboratory of Biochemistry and Molecular Biology, The Rockefeller University, 1230 York Avenue, New York, NY 10065 (United States); Ito, Mitsuhiro, E-mail: itomi@med.kobe-u.ac.jp [Laboratory of Hematology, Division of Medical Biophysics, Kobe University Graduate School of Health Sciences, 7-10-2 Tomogaoka, Suma-ku, Kobe 654-0142 (Japan); Laboratory of Biochemistry and Molecular Biology, The Rockefeller University, 1230 York Avenue, New York, NY 10065 (United States); Department of Family and Community Medicine, Kobe University Graduate School of Medicine, 7-5-1 Kusunoki-cho, Chuo-ku, Kobe 654-0142 (Japan); Consolidated Research Institute for Advanced Science and Medical Care, Waseda University, 3-4-1 Okubo, Shinjuku-ku, Tokyo 159-8555 (Japan)

    2013-10-11

    Highlights: •MED1 is a bona fide T3-dependent coactivator on TSHB promoter. •Mice with LxxLL-mutant MED1 have attenuated TSHβ mRNA and thyroid hormone levels. •MED1 activates TSHB promoter T3-dependently in cultured cells. •T3-dependent MED1 action is enhanced when SRC1/SRC2 or HDAC2 is downregulated. •MED1 is also a T3-independent GATA2/Pit1 coactivator on TSHB promoter. -- Abstract: The MED1 subunit of the Mediator transcriptional coregulator complex is a nuclear receptor-specific coactivator. A negative feedback mechanism of thyroid-stimulating hormone (TSH, or thyrotropin) expression in the thyrotroph in the presence of triiodothyronine (T3) is employed by liganded thyroid hormone receptor β (TRβ) on the TSHβ gene promoter, where conventional histone-modifying coactivators act as corepressors. We now provide evidence that MED1 is a ligand-dependent positive cofactor on this promoter. TSHβ gene transcription was attenuated in MED1 mutant mice in which the nuclear receptor-binding ability of MED1 was specifically disrupted. MED1 stimulated GATA2- and Pit1-mediated TSHβ gene promoter activity in a ligand-independent manner in cultured cells. MED1 also stimulated transcription from the TSHβ gene promoter in a T3-dependent manner. The transcription was further enhanced when the T3-dependent corepressors SRC1, SRC2, and HDAC2 were downregulated. Hence, MED1 is a T3-dependent and -independent coactivator on the TSHβ gene promoter.

  17. SDF-1alpha concentration dependent modulation of RhoA and Rac1 modifies breast cancer and stromal cells interaction

    International Nuclear Information System (INIS)

    Pasquier, Jennifer; Abu-Kaoud, Nadine; Abdesselem, Houari; Madani, Aisha; Hoarau-Véchot, Jessica; Thawadi, Hamda Al.; Vidal, Fabien; Couderc, Bettina; Favre, Gilles; Rafii, Arash

    2015-01-01

    The interaction of SDF-1alpha with its receptor CXCR4 plays a role in the occurrence of distant metastasis in many solid tumors. This interaction increases migration from primary sites as well as homing at distant sites. Here we investigated how SDF-1α could modulate both migration and adhesion of cancer cells through the modulation of RhoGTPases. We show that different concentrations of SDF-1α modulate the balance of adhesion and migration in cancer cells. Increased migration was obtained at 50 and 100 ng/ml of SDF-1α; however migration was reduced at 200 ng/ml. The adhesion between breast cancer cells and BMHC was significantly increased by SDF-1α treatment at 200 ng/ml and reduced using a blocking monoclonal antibody against CXCR4. We showed that at low SDF-1α concentration, RhoA was activated and overexpressed, while at high concentration Rac1 was promoting SDF-1α mediating-cell adhesion. We conclude that SDF-1α concentration modulates migration and adhesion of breast cancer cells, by controlling expression and activation of RhoGTPases. The online version of this article (doi:10.1186/s12885-015-1556-7) contains supplementary material, which is available to authorized users

  18. A Polymorphism in Hepatocyte Nuclear Factor 1 Alpha, rs7310409, Is Associated with Left Main Coronary Artery Disease

    Directory of Open Access Journals (Sweden)

    Rui Liu

    2014-01-01

    Full Text Available Coronary artery disease is the leading cause of mortality and morbidity in the world. Left main coronary artery disease (LMCAD is a particularly severe phenotypic form of CAD and has a genetic basis. We hypothesized that some inflammation- and hyperhomocysteinemia-related gene polymorphisms may contribute to LMCAD susceptibility in a Chinese population. We studied the association between polymorphisms in the genes hepatocyte nuclear factor 1 alpha (HNF1A; rs7310409, G/A, C-reactive protein (rs1800947 and rs3093059 T/C, methylenetetrahydrofolate reductase (rs1801133, C/T, and methylenetetrahydrofolate dehydrogenase (rs1076991, A/G in 402 LMCAD and 804 more peripheral CAD patients in a Chinese population. Genotyping was performed using the matrix-assisted laser desorption/ionization time-of-flight mass spectrometry method. When the HNF1A rs7310409 GG homozygote genotype was used as the reference group, both the individual, GA and AA, and combined GA/AA genotypes were associated with an increased risk of LMCAD. This single nucleotide polymorphism (rs7310409 is strongly associated with plasma CRP levels. In conclusion, the present study provides evidence that the HNF1A rs7310409 G/A functional polymorphism may contribute to the risk of LMCAD.

  19. Interdependence of AMPK and SIRT1 for metabolic adaptation to fasting and exercise in skeletal muscle

    DEFF Research Database (Denmark)

    Cantó, Carles; Jiang, Lake Q; Deshmukh, Atul S

    2010-01-01

    During fasting and after exercise, skeletal muscle efficiently switches from carbohydrate to lipid as the main energy source to preserve glycogen stores and blood glucose levels for glucose-dependent tissues. Skeletal muscle cells sense this limitation in glucose availability and transform...... and lipid utilization genes. Deficient AMPK activity compromises SIRT1-dependent responses to exercise and fasting, resulting in impaired PGC-1alpha deacetylation and blunted induction of mitochondrial gene expression. Thus, we conclude that AMPK acts as the primordial trigger for fasting- and exercise...

  20. Partial Oxygen Pressure Affects the Expression of Prognostic Biomarkers HIF-1 Alpha, Ki67, and CK20 in the Microenvironment of Colorectal Cancer Tissue.

    Science.gov (United States)

    Zhang, Lirong; Hu, Yu; Xi, Ning; Song, Jie; Huang, Wenjing; Song, Shanshan; Liu, Yiting; Liu, Xianying; Xie, Yingjun

    2016-01-01

    Hypoxia is prognostically important in colorectal cancer (CRC) therapy. Partial oxygen pressure (pO 2 ) is an important parameter of hypoxia. The correlation between pO 2 levels and expression levels of prognostic biomarkers was measured in CRC tissues. Human CRC tissues were collected and pO 2 levels were measured by OxyLite. Three methods for tissue fixation were compared, including formalin, Finefix, and Finefix-plus-microwave. Immunohistochemistry (IHC) staining was conducted by using the avidin-biotin complex technique for detecting the antibodies to hypoxia inducible factor-1 (HIF-1) alpha, cytokeratin 20 (CK20), and cell proliferation factor Ki67. The levels of pO 2 were negatively associated with the size of CRC tissues. Finefix-plus-microwave fixation has the potential to replace formalin. Additionally, microwave treatment improved Finefix performance in tissue fixation and protein preservation. The percentage of positive cells and gray values of HIF-1 alpha, CK20, and Ki67 were associated with CRC development ( P < 0.05). The levels of pO 2 were positively related with the gray values of Ki67 and negatively related with the values of HIF-1 alpha and CK20 ( P < 0.05). Thus, the levels of microenvironmental pO 2 affect the expression of predictive biomarkers HIF-1 alpha, CK20, and Ki67 in the development of CRC tissues.

  1. Expression and regulation of HIF-1 alpha in macrophages under inflammatory conditions; significant reduction of VEGF by CaMKII inhibitor

    NARCIS (Netherlands)

    Westra, Johanna; Brouwer, Elisabeth; van Roosmalen, Ingrid A. M.; Doornbos-van der Meer, Berber; van Leeuwen, Miek A.; Posthumus, Marcel D.; Kallenberg, Cees G. M.

    2010-01-01

    Background: Macrophages expressing the pro-angiogenic transcription factor hypoxia-inducible factor (HIF)-1alpha have been demonstrated in rheumatoid arthritis (RA) in the synovial tissue. Aim of the present study was to investigate intracellular signal transduction regulation of pro-inflammatory

  2. Low-dose radiation pretreatment improves survival of human ceiling culture-derived proliferative adipocytes (ccdPAs) under hypoxia via HIF-1 alpha and MMP-2 induction

    International Nuclear Information System (INIS)

    Adachi, Naoki; Kubota, Yoshitaka; Kosaka, Kentarou; Akita, Shinsuke; Sasahara, Yoshitarou; Kira, Tomoe; Kuroda, Masayuki; Mitsukawa, Nobuyuki; Bujo, Hideaki; Satoh, Kaneshige

    2015-01-01

    Poor survival is a major problem of adipocyte transplantation. We previously reported that VEGF and MMPs secreted from transplanted adipocytes are essential for angiogenesis and adipogenesis. Pretreatment with low-dose (5 Gy) radiation (LDR) increased VEGF, MMP-2, and HIF-1 alpha mRNA expression in human ceiling culture-derived proliferative adipocytes (hccdPAs). Gene expression after LDR differed between adipose-derived stem cells (hASCs) and hccdPAs. Pretreatment with LDR improved the survival of hccdPAs under hypoxia, which is inevitable in the early stages after transplantation. Upregulation of VEGF and MMP-2 after LDR in hccdPAs is mediated by HIF-1 alpha expression. Our results suggest that pretreatment with LDR may improve adipocyte graft survival in a clinical setting through upregulation of VEGF and MMP-2 via HIF-1 alpha. - Highlights: • Ceiling culture-derived proliferative adipocytes (ccdPAs) react to radiation. • Low-dose radiation (LDR) pretreatment improves survival of ccdPAs under hypoxia. • Gene expression after LDR differs between ccdPAs and adipose-derived stem cells. • LDR-induced increase in MMP-2 and VEGF is dependent on HIF-1 alpha induction. • LDR pretreatment may improve the adipocyte graft survival rate in clinical settings

  3. Low-dose radiation pretreatment improves survival of human ceiling culture-derived proliferative adipocytes (ccdPAs) under hypoxia via HIF-1 alpha and MMP-2 induction

    Energy Technology Data Exchange (ETDEWEB)

    Adachi, Naoki [Department of Plastic Surgery, Chiba University, 1-8-1, Inohana, Chuo-ku, Chiba-city, Chiba, #260-8677 (Japan); Kubota, Yoshitaka, E-mail: kubota-cbu@umin.ac.jp [Department of Plastic Surgery, Chiba University, 1-8-1, Inohana, Chuo-ku, Chiba-city, Chiba, #260-8677 (Japan); Kosaka, Kentarou; Akita, Shinsuke; Sasahara, Yoshitarou; Kira, Tomoe [Department of Plastic Surgery, Chiba University, 1-8-1, Inohana, Chuo-ku, Chiba-city, Chiba, #260-8677 (Japan); Kuroda, Masayuki [Center for Advanced Medicine, Chiba University, 1-8-1, Inohana, Chuo-ku, Chiba-city, Chiba, #260-8677 (Japan); Mitsukawa, Nobuyuki [Department of Plastic Surgery, Chiba University, 1-8-1, Inohana, Chuo-ku, Chiba-city, Chiba, #260-8677 (Japan); Bujo, Hideaki [Department of Clinical-Laboratory and Experimental-Research Medicine, Toho University, Sakura Medical Center, 564-1 Shimoshizu, Sakura-shi, Chiba, #285-8741 (Japan); Satoh, Kaneshige [Department of Plastic Surgery, Chiba University, 1-8-1, Inohana, Chuo-ku, Chiba-city, Chiba, #260-8677 (Japan)

    2015-08-07

    Poor survival is a major problem of adipocyte transplantation. We previously reported that VEGF and MMPs secreted from transplanted adipocytes are essential for angiogenesis and adipogenesis. Pretreatment with low-dose (5 Gy) radiation (LDR) increased VEGF, MMP-2, and HIF-1 alpha mRNA expression in human ceiling culture-derived proliferative adipocytes (hccdPAs). Gene expression after LDR differed between adipose-derived stem cells (hASCs) and hccdPAs. Pretreatment with LDR improved the survival of hccdPAs under hypoxia, which is inevitable in the early stages after transplantation. Upregulation of VEGF and MMP-2 after LDR in hccdPAs is mediated by HIF-1 alpha expression. Our results suggest that pretreatment with LDR may improve adipocyte graft survival in a clinical setting through upregulation of VEGF and MMP-2 via HIF-1 alpha. - Highlights: • Ceiling culture-derived proliferative adipocytes (ccdPAs) react to radiation. • Low-dose radiation (LDR) pretreatment improves survival of ccdPAs under hypoxia. • Gene expression after LDR differs between ccdPAs and adipose-derived stem cells. • LDR-induced increase in MMP-2 and VEGF is dependent on HIF-1 alpha induction. • LDR pretreatment may improve the adipocyte graft survival rate in clinical settings.

  4. Partial Oxygen Pressure Affects the Expression of Prognostic Biomarkers HIF-1 Alpha, Ki67, and CK20 in the Microenvironment of Colorectal Cancer Tissue

    Directory of Open Access Journals (Sweden)

    Lirong Zhang

    2016-01-01

    Full Text Available Hypoxia is prognostically important in colorectal cancer (CRC therapy. Partial oxygen pressure (pO2 is an important parameter of hypoxia. The correlation between pO2 levels and expression levels of prognostic biomarkers was measured in CRC tissues. Human CRC tissues were collected and pO2 levels were measured by OxyLite. Three methods for tissue fixation were compared, including formalin, Finefix, and Finefix-plus-microwave. Immunohistochemistry (IHC staining was conducted by using the avidin-biotin complex technique for detecting the antibodies to hypoxia inducible factor-1 (HIF-1 alpha, cytokeratin 20 (CK20, and cell proliferation factor Ki67. The levels of pO2 were negatively associated with the size of CRC tissues. Finefix-plus-microwave fixation has the potential to replace formalin. Additionally, microwave treatment improved Finefix performance in tissue fixation and protein preservation. The percentage of positive cells and gray values of HIF-1 alpha, CK20, and Ki67 were associated with CRC development (P<0.05. The levels of pO2 were positively related with the gray values of Ki67 and negatively related with the values of HIF-1 alpha and CK20 (P<0.05. Thus, the levels of microenvironmental pO2 affect the expression of predictive biomarkers HIF-1 alpha, CK20, and Ki67 in the development of CRC tissues.

  5. Role of the N-terminal activation domain of coactivator CoCoA in mediating transcriptional activation by β-catenin*

    OpenAIRE

    Yang, Catherine K.; Kim, Jeong Hoon; Stallcup, Michael R.

    2006-01-01

    The coiled-coil coactivator (CoCoA) is involved in transcriptional activation of target genes by nuclear receptors and the xenobiotic aryl hydrocarbon receptor, as well as target genes of the Wnt signaling pathway, which is mediated by the lymphocyte enhancer factor (LEF)/T cell factor transcription factors and the coactivator β-catenin. The recruitment of CoCoA by nuclear receptors is accomplished by the interaction of the central coiled-coiled domain of CoCoA with p160 coactivators; the C-t...

  6. Polymorphisms in the hypoxia-inducible factor 1 alpha gene in Mexican patients with preeclampsia: A case-control study

    Directory of Open Access Journals (Sweden)

    Nava-Salazar Sonia

    2011-03-01

    Full Text Available Abstract Background Although the etiology of preeclampsia is still unclear, recent work suggests that changes in circulating angiogenic factors play a key role in its pathogenesis. In the trophoblast of women with preeclampsia, hypoxia-inducible factor 1 alpha (HIF-1α is over-expressed, and induces the expression of non-angiogenic factors and inhibitors of trophoblast differentiation. This observation prompted the study of HIF-1α and its relation to preeclampsia. It has been described that the C1772T (P582S and G1790A (A588T polymorphisms of the HIF1A gene have significantly greater transcriptional activity, correlated with an increased expression of their proteins, than the wild-type sequence. In this work, we studied whether either or both HIF1A variants contribute to preeclampsia susceptibility. Results Genomic DNA was isolated from 150 preeclamptic and 105 healthy pregnant women. Exon 12 of the HIF1A gene was amplified by PCR, and the genotypes of HIF1A were determined by DNA sequencing. In preeclamptic women and controls, the frequencies of the T allele for C1772T were 4.3 vs. 4.8%, and the frequencies of the A allele for G1790A were 0.0 vs. 0.5%, respectively. No significant differences were found between groups. Conclusion The frequency of the C1772T and G1790A polymorphisms of the HIF1A gene is very low, and neither polymorphism is associated with the development of preeclampsia in the Mexican population.

  7. The effect of incorporation of SDF-1alpha into PLGA scaffolds on stem cell recruitment and the inflammatory response.

    Science.gov (United States)

    Thevenot, Paul T; Nair, Ashwin M; Shen, Jinhui; Lotfi, Parisa; Ko, Cheng-Yu; Tang, Liping

    2010-05-01

    Despite significant advances in the understanding of tissue responses to biomaterials, most implants are still plagued by inflammatory responses which can lead to fibrotic encapsulation. This is of dire consequence in tissue engineering, where seeded cells and bioactive components are separated from the native tissue, limiting the regenerative potential of the design. Additionally, these interactions prevent desired tissue integration and angiogenesis, preventing functionality of the design. Recent evidence supports that mesenchymal stem cells (MSC) and hematopoietic stem cells (HSC) can have beneficial effects which alter the inflammatory responses and improve healing. The purpose of this study was to examine whether stem cells could be targeted to the site of biomaterial implantation and whether increasing local stem cell responses could improve the tissue response to PLGA scaffold implants. Through incorporation of SDF-1alpha through factor adsorption and mini-osmotic pump delivery, the host-derived stem cell response can be improved resulting in 3X increase in stem cell populations at the interface for up to 2 weeks. These interactions were found to significantly alter the acute mast cell responses, reducing the number of mast cells and degranulated mast cells near the scaffold implants. This led to subsequent downstream reduction in the inflammatory cell responses, and through altered mast cell activation and stem cell participation, increased angiogenesis and decreased fibrotic responses to the scaffold implants. These results support that enhanced recruitment of autologous stem cells can improve the tissue responses to biomaterial implants through modifying/bypassing inflammatory cell responses and jumpstarting stem cell participation in healing at the implant interface. Copyright 2010 Elsevier Ltd. All rights reserved.

  8. [Genetic cloning and expression of hypoxia inducible factor 1 alpha in high altitude hypoxic adaptation species Tibetan antelope (Pantholops hodgsonii)].

    Science.gov (United States)

    Liu, Fang; Wuren, Tana; Ma, Lan; Yang, Ying-Zhong; Ge, Ri-Li

    2011-12-25

    In order to investigate the role of the hypoxia inducible factor 1 alpha (HIF-1α) in the adaptation mechanism to high altitude hypoxia, the cloning of the HIF-1α gene cDNA of Tibetan antelope (Pantholops hodgsonii), using RT-PCR and RACE, was applied, and the comparative analysis of the tissue-specific expressions of HIF-1α among Tibetan antelope, Tibetan sheep and plain sheep was performed using real-time PCR and Western blot. The sequence analysis indicated that the cDNA sequences acquired by cloning from the HIF-1α gene of Tibetan antelope comprised a 2 471-bp open reading frame (ORF) and a 1 911-bp 3'UTR. The similarity between its coding sequence, predicted amino acid sequence and HIF-1α of other mammals exceeded 87%, in which the similarity with cow was up to more than 98%, which showed that this sequence was the cDNA of HIF-1α of Tibetan antelope. The results of real-time PCR and Western blot showed that expressions of HIF-1α mRNA and protein appeared in Tibetan antelope's lung, cardiac muscle and skeletal muscle, with the highest expression in lung. HIF-1α mRNA and protein had obvious differential expression in these tissues. Further research showed that Tibetan antelope and Tibetan sheep possessed higher expressions of HIF-1α protein in the three tissues above-mentioned compared with plain sheep, and the expressions of HIF-1α mRNA and protein in Tibetan antelope's lung, cardiac muscle and skeletal muscle were higher than those of Tibetan sheep. It illustrates that the hypoxic HIF-1α-specific expression is one of the molecular bases of high altitude hypoxia adaptation in Tibetan antelope.

  9. Cell cycle sensitivity of HL-60 cells to the differentiation-inducing effects of 1-alpha,25-dihydroxyvitamin D3

    International Nuclear Information System (INIS)

    Studzinski, G.P.; Bhandal, A.K.; Brelvi, Z.S.

    1985-01-01

    A recently described system for monocyte-like differentiation of HL-60 cells was utilized to determine if the initiation of this pathway can be linked to a set of replicative cellular events. The standard induction system consisted of a 4-h exposure to 100 nM 1-alpha,25-dihydroxyvitamin D3 [1,25(OH)2D3] followed by determination of nonspecific esterase and phagocytic activity 24 h later. The cell cycle status was ascertained by the incorporation of [ 3 H]thymidine and autoradiography. Studies in which cell cycle block in the G1/S phase boundary region was produced by a partial inhibition of DNA synthesis with thymidine, or sodium butyrate, showed that the exposure of such semisynchronous cultures to 1,25(OH)2D3 resulted in an increased proportion of differentiated cells. Conversely, blocking the cell cycle with vinblastine (G2/M block) or theobromine (mid-G1 block) inhibited the initiation of differentiation by 1,25(OH)2D3. Experiments in which the differentiated cells were examined for the cell cycle position at the time of the exposure to 1,25(OH)2D3 by [ 3 H]thymidine labeling and autoradiography confirmed that the late G1 and early S phase cells are those which predominate in the differentiated fraction of 1,25(OH)2D3-treated HL-60 cultures. These results link pre- and early replicative cellular events to the induction of monocytic differentiation by 1,25(OH)2D3

  10. Staurosporine, but not Ro 31-8220, induces interleukin 2 production and synergizes with interleukin 1alpha in EL4 thymoma cells.

    Science.gov (United States)

    Mahon, T M; Matthews, J S; O'Neill, L A

    1997-07-01

    Protein kinase C (PKC) has been implicated in interleukin 1 (IL1) signal transduction in a number of cellular systems, either as a key event in IL1 action or as a negative regulator. Here we have examined the effects of two PKC inhibitors, staurosporine and the more selective agent Ro 31-8220, on IL1 responses in the murine thymoma line EL4.NOB-1. A 1 h pulse of staurosporine was found to strongly potentiate the induction of IL2 by IL1alpha in these cells. In contrast, neither a pulse nor prolonged incubation with Ro 31-8220 affected the response to IL1alpha. Both agents blocked the response to PMA, however. A 1 h pulse of staurosporine was also found to induce IL2 production on its own, activate the transcription factor nuclear factor kappaB (NFkappaB) and increase the expression of a NFkappaB-linked reporter gene. It synergized with IL1alpha in all of these responses. Ro 31-8220 was again without effect, although both staurosporine and Ro 31-8220 blocked the activation of NFkappaB by PMA. Finally, staurosporine caused the translocation of PKC-alpha and -epsilon, and to a lesser extent PKC-beta, but not PKC-θ or -zeta, from the cytosol to the membrane, although a similar effect was observed with Ro 31-8220. The results suggest that PKC is not involved in IL1alpha signalling in EL4 cells. Furthermore, the potentiating effect of staurosporine on IL1alpha action does not involve PKC inhibition, and is likely to be at the level of NFkappaB activation.

  11. A prevalent amino acid polymorphism at codon 98 (Ala98Val) of the hepatocyte nuclear factor-1alpha is associated with maturity-onset diabetes of the young and younger age at onset of type 2 diabetes in Asian Indians

    DEFF Research Database (Denmark)

    Anuradha, Shekher; Radha, Venkatesan; Deepa, Raj

    2005-01-01

    Among Europeans, mutations in the hepatocyte nuclear factor-1alpha (HNF1alpha) gene are associated with the most common form of maturity-onset diabetes of the young (MODY)3. In Asian Indians, type 2 diabetes occurs earlier and often overlaps with MODY, but the genetics of the latter are unknown....... The aim of this study was to estimate the prevalence of Ala98Val polymorphism of the HNF1alpha gene in different types of diabetes in Asian Indians....

  12. Regulation of Brown and White Adipocyte Transcriptome by the Transcriptional Coactivator NT-PGC-1α.

    Directory of Open Access Journals (Sweden)

    Jihyun Kim

    Full Text Available The β3-adrenergic receptor (AR signaling pathway is a major component of adaptive thermogenesis in brown and white adipose tissue during cold acclimation. The β3-AR signaling highly induces the expression of transcriptional coactivator PGC-1α and its splice variant N-terminal (NT-PGC-1α, which in turn activate the transcription program of adaptive thermogenesis by co-activating a number of transcription factors. We previously reported that NT-PGC-1α is able to increase mitochondrial number and activity in cultured brown adipocytes by promoting the expression of mitochondrial and thermogenic genes. In the present study, we performed genome-wide profiling of NT-PGC-1α-responsive genes in brown adipocytes to identify genes potentially regulated by NT-PGC-1α. Canonical pathway analysis revealed that a number of genes upregulated by NT-PGC-1α are highly enriched in mitochondrial pathways including fatty acid transport and β-oxidation, TCA cycle and electron transport system, thus reinforcing the crucial role of NT-PGC-1α in the enhancement of mitochondrial function. Moreover, canonical pathway analysis of NT-PGC-1α-responsive genes identified several metabolic pathways including glycolysis and fatty acid synthesis. In order to validate the identified genes in vivo, we utilized the FL-PGC-1α-/- mouse that is deficient in full-length PGC-1α (FL-PGC-1α but expresses a slightly shorter and functionally equivalent form of NT-PGC-1α (NT-PGC-1α254. The β3-AR-induced increase of NT-PGC-1α254 in FL-PGC-1α-/- brown and white adipose tissue was closely associated with elevated expression of genes involved in thermogenesis, mitochondrial oxidative metabolism, glycolysis and fatty acid synthesis. Increased adipose tissue thermogenesis by β3-AR activation resulted in attenuation of adipose tissue expansion in FL-PGC-1α-/- adipose tissue under the high-fat diet condition. Together, the data strengthen our previous findings that NT-PGC-1

  13. Inositol polyphosphate multikinase is a coactivator for serum response factor-dependent induction of immediate early genes

    Science.gov (United States)

    Kim, Eunha; Tyagi, Richa; Lee, Joo-Young; Park, Jina; Kim, Young-ran; Beon, Jiyoon; Chen, Po Yu; Cha, Jiyoung Y.; Snyder, Solomon H.; Kim, Seyun

    2013-01-01

    Inositol polyphosphate multikinase (IPMK) is a notably pleiotropic protein. It displays both inositol phosphate kinase and phosphatidylinositol kinase catalytic activities. Noncatalytically, IPMK stabilizes the mammalian target of rapamycin complex 1 and acts as a transcriptional coactivator for CREB-binding protein/E1A binding protein p300 and tumor suppressor protein p53. Serum response factor (SRF) is a major transcription factor for a wide range of immediate early genes. We report that IPMK, in a noncatalytic role, is a transcriptional coactivator for SRF mediating the transcription of immediate early genes. Stimulation by serum of many immediate early genes is greatly reduced by IPMK deletion. IPMK stimulates expression of these genes, an influence also displayed by catalytically inactive IPMK. IPMK acts by binding directly to SRF and thereby enhancing interactions of SRF with the serum response element of diverse genes. PMID:24248338

  14. [Effects of feixin decoction on the contents of hypoxia-inducible factor-1alpha and vascular endothelial growth factor in the rat model of hypoxic pulmonary hypertension].

    Science.gov (United States)

    He, Hong-Jun; Dai, Ai-Guo

    2012-05-01

    To explore the effects of Feixin Decoction (FXD) on the hypoxia-inducible factor-1alpha (HIF-1alpha) and vascular endothelial growth factor (VEGF) in the rat model of hypoxic pulmonary hypertension (HPH), and to study its mechanisms for treating HPH. Forty healthy male SD rats were randomly divided into four groups, i. e., the normal control group, the HPH model group, the FXD group, and the Nifedipine group, 10 rats in each group. The HPH rat model was prepared using normal pressure intermittent hypoxia method. Except the normal control group, rats in the rest groups were fed in a self-made hypoxic plexiglass cabin, with the poor oxygen condition for 8 h daily for 14 successive days. Then the distilled water (at 30 mL/kg) was given by gastrogavage to rats in the normal control group and the HPH model group. FXD (at 28 g/kg) and Nifedipine (at 20 mg/kg) were given by gastrogavage to rats in the FXD group and the Nifedipine group respectively, once daily, for 14 successive days. Besides, hypoxia was continued for 14 days while medicating. The mean pulmonary artery pressure (mPAP) was detected on the second day after the last medication. The morphology of the pulmonary arteriole was detected. The ratio of pulmonary artery wall area and tube area (WA%) was determined. The protein and mRNA expressions of HIF-1alpha and VEGF were detected using immunohistochemistry and in situ hybridization technique. Compared with the normal control group, mPAP, WA%, and the protein and mRNA expressions of HIF-1alpha and VEGF significantly increased in the model group (P < 0.01, P < 0.05). Compared with the HPH model group, mPAP, WA%, and the protein and mRNA expressions of HIF-1alpha and VEGF significantly decreased in the FXD group (P < 0.01, P < 0.05). FXD down-regulated the expression of VEGF through decreasing the expression of HIF-1alpha. One of its mechanisms for treating HPH might be partially due to reversing the remodeling of pulmonary vascular smooth muscle.

  15. Abscisic acid promotes proteasome-mediated degradation of the transcription coactivator NPR1 in Arabidopsis thaliana.

    Science.gov (United States)

    Ding, Yezhang; Dommel, Matthew; Mou, Zhonglin

    2016-04-01

    Proteasome-mediated turnover of the transcription coactivator NPR1 is pivotal for efficient activation of the broad-spectrum plant immune responses known as localized acquired resistance (LAR) and systemic acquired resistance (SAR) in adjacent and systemic tissues, respectively, and requires the CUL3-based E3 ligase and its adaptor proteins, NPR3 and NPR4, which are receptors for the signaling molecule salicylic acid (SA). It has been shown that SA prevents NPR1 turnover under non-inducing and LAR/SAR-inducing conditions, but how cellular NPR1 homeostasis is maintained remains unclear. Here, we show that the phytohormone abscisic acid (ABA) and SA antagonistically influence cellular NPR1 protein levels. ABA promotes NPR1 degradation via the CUL3(NPR) (3/) (NPR) (4) complex-mediated proteasome pathway, whereas SA may protect NPR1 from ABA-promoted degradation through phosphorylation. Furthermore, we demonstrate that the timing and strength of SA and ABA signaling are critical in modulating NPR1 accumulation and target gene expression. Perturbing ABA or SA signaling in adjacent tissues alters the temporal dynamic pattern of NPR1 accumulation and target gene transcription. Finally, we show that sequential SA and ABA treatment leads to dynamic changes in NPR1 protein levels and target gene expression. Our results revealed a tight correlation between sequential SA and ABA signaling and dynamic changes in NPR1 protein levels and NPR1-dependent transcription in plant immune responses. © 2016 The Authors The Plant Journal © 2016 John Wiley & Sons Ltd.

  16. Mitochondrial fusion is increased by the nuclear coactivator PGC-1beta.

    Directory of Open Access Journals (Sweden)

    Marc Liesa

    Full Text Available There is no evidence to date on whether transcriptional regulators are able to shift the balance between mitochondrial fusion and fission events through selective control of gene expression.Here, we demonstrate that reduced mitochondrial size observed in knock-out mice for the transcriptional regulator PGC-1beta is associated with a selective reduction in Mitofusin 2 (Mfn2 expression, a mitochondrial fusion protein. This decrease in Mfn2 is specific since expression of the remaining components of mitochondrial fusion and fission machinery were not affected. Furthermore, PGC-1beta increases mitochondrial fusion and elongates mitochondrial tubules. This PGC-1beta-induced elongation specifically requires Mfn2 as this process is absent in Mfn2-ablated cells. Finally, we show that PGC-1beta increases Mfn2 promoter activity and transcription by coactivating the nuclear receptor Estrogen Related Receptor alpha (ERRalpha.Taken together, our data reveal a novel mechanism by which mammalian cells control mitochondrial fusion. In addition, we describe a novel role of PGC-1beta in mitochondrial physiology, namely the control of mitochondrial fusion mainly through Mfn2.

  17. Immunohistochemical localization of steroid receptor coactivators in chondrosarcoma: an in vivo tissue microarray study.

    Science.gov (United States)

    Li, Wei; Fu, Jingshu; Bian, Chen; Zhang, Jiqiang; Xie, Zhao

    2014-12-01

    Chondrosarcoma is the second most common type of primary bone malignancy following up osteosarcoma, characterized by resistance to conventional chemotherapeutic agents and radiation regimens. The p160 family members steroid receptor coactivator-1 and -3 (SRC-1 and SRC-3) have been implied in the regulation of cancer growth, migration, invasion, metastasis and chemotherapeutic resistance; but we still lack detailed information about the levels of SRCs in chondrosarcoma. In this study, expression of SRC-1 and SRC-3 in chondrosarcoma was examined by immunohistochemistry with tissue microarrays; the four score system (0, 1, 2 and 3) was used to evaluate the staining. The results showed that there were no gender-, site- or age-differences regarding the expression of SRC-1 or SRC-3 (p>0.05); organ (bone or cartilage) -differences were only detected for SRC-1 but not SRC-3 (pchondrosarcoma, may be novel targets for the prognosis and/or treatment of chondrosarcoma, would have opened a new avenue and established foundation for studying chondrosarcoma. Copyright © 2014 Elsevier GmbH. All rights reserved.

  18. Normal postural responses preceding shoulder flexion: co-activation or asymmetric activation of transverse abdominis?

    Science.gov (United States)

    Davarian, Sanaz; Maroufi, Nader; Ebrahimi, Esmaeil; Parnianpour, Mohammad; Farahmand, Farzam

    2014-01-01

    It is suggested that activation of the transverse abdominis muscle has a stabilizing effect on the lumbar spine by raising intra-abdominal pressure without added disc compression. However, its feedforward activity has remained a controversial issue. In addition, research regarding bilateral activation of trunk muscles during a unilateral arm movement is limited. The aim of this study was to evaluate bilateral anticipatory activity of trunk muscles during unilateral arm flexion. Eighteen healthy subjects (aged 25 ± 3.96 years) participated in this study and performed 10 trials of rapid arm flexion in response to a visual stimulus. The electromyographic activity of the right anterior deltoid (AD) and bilateral trunk muscles including the transverse abdominis/internal oblique (TA/IO), superficial lumbar multifidus (SLM) and lumbar erector spine (LES) was recorded. The onset latency and anticipatory activity of the recorded trunk muscles were calculated. The first muscle activated in anticipation of the right arm flexion was the left TA/IO. The right TA/IO activated significantly later than all other trunk muscles (P 0.05). Healthy subjects showed no bilateral anticipatory co-activation of TA/IO in unilateral arm elevation. Further investigations are required to delineate normal muscle activation pattern in healthy subjects prior to prescribing bilateral activation training of transverse abdominis for subjects with chronic low back pain.

  19. Can Co-Activation of Nrf2 and Neurotrophic Signaling Pathway Slow Alzheimer’s Disease?

    Directory of Open Access Journals (Sweden)

    Kelsey E. Murphy

    2017-05-01

    Full Text Available Alzheimer’s disease (AD is a multifaceted disease that is hard to treat by single-modal treatment. AD starts with amyloid peptides, mitochondrial dysfunction, and oxidative stress and later is accompanied with chronic endoplasmic reticulum (ER stress and autophagy dysfunction, resulting in more complicated pathogenesis. Currently, few treatments can modify the complicated pathogenic progress of AD. Compared to the treatment with exogenous antioxidants, the activation of global antioxidant defense system via Nrf2 looks more promising in attenuating oxidative stress in AD brains. Accompanying the activation of the Nrf2-mediated antioxidant defense system that reduce the AD-causative factor, oxidative stress, it is also necessary to activate the neurotrophic signaling pathway that replaces damaged organelles and molecules with new ones. Thus, the dual actions to activate both the Nrf2 antioxidant system and neurotrophic signaling pathway are expected to provide a better strategy to modify AD pathogenesis. Here, we review the current understanding of AD pathogenesis and neuronal defense systems and discuss a possible way to co-activate the Nrf2 antioxidant system and neurotrophic signaling pathway with the hope of helping to find a better strategy to slow AD.

  20. Nuclear localization of the transcriptional coactivator YAP is associated with invasive lobular breast cancer.

    Science.gov (United States)

    Vlug, Eva J; van de Ven, Robert A H; Vermeulen, Jeroen F; Bult, Peter; van Diest, Paul J; Derksen, Patrick W B

    2013-10-01

    Yes Associated Protein (YAP) has been implicated in the control of organ size by regulating cell proliferation and survival. YAP is a transcriptional coactivator that controls cellular responses through interaction with TEAD transcription factors in the nucleus, while its transcriptional functions are inhibited by phosphorylation-dependent translocation to the cytosol. YAP overexpression has been associated with different types of cancer, such as lung, skin, prostate, ovary and liver cancer. Recently, YAP was linked to E-cadherin-dependent regulation of contact inhibition in breast cancer cells. In this study we examined YAP protein expression and cellular localization in 237 cases of human invasive breast cancer by immunohistochemistry and related its expression to clinicopathological features and E-cadherin expression. We observed that invasive lobular carcinoma is characterized by higher expression levels of both nuclear and cytosolic YAP (p invasive breast cancer. We observed that high nuclear and cytosolic YAP expression are associated with the E-cadherin deficient breast cancer subtype ILC (p cancers and conditional mouse models of human lobular breast cancer. Since our data indicate that nuclear YAP localization is more common in breast cancers lacking functional adherens junctions, it suggests that YAP-mediated transcription may be involved in the development and progression of invasive lobular breast cancer.

  1. Discerning measures of conscious brain processes associated with superior early motor performance: Capacity, coactivation, and character.

    Science.gov (United States)

    van Duijn, Tina; Buszard, Tim; Hoskens, Merel C J; Masters, Rich S W

    2017-01-01

    This study explored the relationship between working memory (WM) capacity, corticocortical communication (EEG coherence), and propensity for conscious control of movement during the performance of a complex far-aiming task. We were specifically interested in the role of these variables in predicting motor performance by novices. Forty-eight participants completed (a) an assessment of WM capacity (an adapted Rotation Span task), (b) a questionnaire that assessed the propensity to consciously control movement (the Movement Specific Reinvestment Scale), and (c) a hockey push-pass task. The hockey push-pass task was performed in a single task (movement only) condition and a combined task (movement plus decision) condition. Electroencephalography (EEG) was used to examine brain activity during the single task. WM capacity best predicted single task performance. WM capacity in combination with T8-Fz coherence (between the visuospatial and motor regions of the brain) best predicted combined task performance. We discuss the implied roles of visuospatial information processing capacity, neural coactivation, and propensity for conscious processing during performance of complex motor tasks. © 2017 Elsevier B.V. All rights reserved.

  2. [Proposal of a conceptual method of supportive care for co-active patients].

    Science.gov (United States)

    Abidli, Yamine; Piette, Danielle; Casini, Annalisa

    2015-01-01

    There is a broad consensus on the importance for health professionals to support co-active patients. However, in practice, very few "patient care partnership" approaches have been developed. We hypothesized that the lack of investment in supporting patient care partnerships is due to the lack of interest in the skills needed by caregivers to provide such support. This paper intends to address thisgap. The patient care partnership method is studied, adapted and developed from existing models. It complements, harmonizes and integrates various schools of thought arising from the need to place the patient at the center of care and life in general. The patient care partnership method includes 7 stages during which the professional accompanies the patient through the process of care. The methodological approach for training professionals is designed to ensure that professionals experience the change as well as its difficulties of the change they expect from the patient in the care relationship. This method now needs to be validated by the experience of other professionals in order define the limits of application and to allow further development.

  3. Mutation analysis of peroxisome proliferator-activated receptor-gamma coactivator-1 (PGC-1) and relationships of identified amino acid polymorphisms to Type II diabetes mellitus

    DEFF Research Database (Denmark)

    Ek, J; Andersen, G; Urhammer, S A

    2001-01-01

    This study aimed to investigate if variability in the peroxisome proliferator-activated receptor-gamma coactivator-1 (PGC-1) gene is associated with Type II (non-insulin-dependent) diabetes mellitus.......This study aimed to investigate if variability in the peroxisome proliferator-activated receptor-gamma coactivator-1 (PGC-1) gene is associated with Type II (non-insulin-dependent) diabetes mellitus....

  4. CCAAT/Enhancer Binding Protein-β Is a Transcriptional Regulator of Peroxisome-Proliferator-Activated Receptor-γ Coactivator-1α in the Regenerating Liver

    OpenAIRE

    Wang, Haitao; Peiris, T. Harshani; Mowery, A.; Le Lay, John; Gao, Yan; Greenbaum, Linda E.

    2008-01-01

    The transcriptional coactivator peroxisome-proliferator-activated receptor-γ coactivator-1α (PGC-1α) is induced in the liver in response to fasting and coordinates the activation of targets necessary for increasing energy production for gluconeogenesis and ketogenesis. After partial hepatectomy, the liver must restore its mass while maintaining metabolic homeostasis to ensure survival. Here we report that PGC-1α is rapidly and dramatically induced after hepatectomy, with an amplitude of induc...

  5. WORKABILITY OF A MANAGEMENT CONTROL MODEL IN SERVICE ORGANIZATIONS: A COMPARATIVE STUDY OF REACTIVE, PROACTIVE AND COACTIVE PHILOSOPHIES

    Directory of Open Access Journals (Sweden)

    Joshua Onome Imoniana

    2006-11-01

    Full Text Available The main objective of this study was to compare and contrast the three philosophies of management control models in the process of decision-making, namely reactive, proactive and the coactive. Research methodology was based on literature review and descriptive/exploratory approach. Additionally, a survey of 20 service organizations was carried out in order to make the analysis wider-reaching. In order to do that, the following steps were followed: firstly, fundamentals of reactive, proactive and coactive models were highlighted; secondly, management behaviors in the three approaches were compared, with concepts and their practical application being highlighted, thus retrieving managerial relationships in the organization. In so doing, we draw the hypothesis that middle and top managers who adopt control models that are distant from a more coactive one, usually spend a greater number of working hours in problem-solving, leaving little or no time for planning purposes. Finally, for study consolidation purpose, we have adopted qualitative data collection, whereby a content analysis was carried out with the assistance of six categories. Results have shown the need for a change in management paradigms so that firms are not only compared through financial perspectives, without considering the analysis of management control models which, according to this study, directly influence the operational results of the organizations.

  6. Hormonal regulation of steroid receptor coactivator-1 mRNA in the male and female green anole brain.

    Science.gov (United States)

    Kerver, H N; Wade, J

    2015-03-01

    Green anole lizards are seasonal breeders, with male sexual behaviour primarily regulated by an annual increase in testosterone. Morphological, biochemical and behavioural changes associated with reproduction are activated by testosterone, generally with a greater effect in the breeding season (BS) than in the nonbreeding season (NBS). The present study investigates the possibility that differences in a steroid receptor coactivator may regulate this seasonal difference in responsiveness to testosterone. In situ hybridisation was used to examine the expression of steroid receptor coactivator-1 (SRC-1) in the brains of gonadally intact male and female green anoles across breeding states. A second experiment examined gonadectomised animals with and without testosterone treatment. Gonadally intact males had more SRC-1 expressing cells in the preoptic area and larger volumes of this region as defined by these cells than females. Main effects of both sex and season (males > females and BS > NBS) were present in cell number and volume of the ventromedial hypothalamus. An interaction between sex and season suggested that high expression in BS males was driving these effects. In hormone-manipulated animals, testosterone treatment increased both the number of SRC-1 expressing cells in and volumes of the preoptic area and amygdala. These results suggest that testosterone selectively regulates SRC-1, and that this coactivator may play a role in facilitating reproductive behaviours across both sexes. However, changes in SRC-1 expression are not likely responsible for the seasonal change in responsiveness to testosterone. © 2014 British Society for Neuroendocrinology.

  7. Recent progress in the development of protein-protein interaction inhibitors targeting androgen receptor-coactivator binding in prostate cancer.

    Science.gov (United States)

    Biron, Eric; Bédard, François

    2016-07-01

    The androgen receptor (AR) is a key regulator for the growth, differentiation and survival of prostate cancer cells. Identified as a primary target for the treatment of prostate cancer, many therapeutic strategies have been developed to attenuate AR signaling in prostate cancer cells. While frontline androgen-deprivation therapies targeting either the production or action of androgens usually yield favorable responses in prostate cancer patients, a significant number acquire treatment resistance. Known as the castration-resistant prostate cancer (CRPC), the treatment options are limited for this advanced stage. It has been shown that AR signaling is restored in CRPC due to many aberrant mechanisms such as AR mutations, amplification or expression of constitutively active splice-variants. Coregulator recruitment is a crucial regulatory step in AR signaling and the direct blockade of coactivator binding to AR offers the opportunity to develop therapeutic agents that would remain effective in prostate cancer cells resistant to conventional endocrine therapies. Structural analyses of the AR have identified key surfaces involved in protein-protein interaction with coregulators that have been recently used to design and develop promising AR-coactivator binding inhibitors. In this review we will discuss the design and development of small-molecule inhibitors targeting the AR-coactivator interactions for the treatment of prostate cancer. Copyright © 2015 Elsevier Ltd. All rights reserved.

  8. Proactive and coactive interference in age-related performance in a recognition-based operation span task.

    Science.gov (United States)

    Zeintl, Melanie; Kliegel, Matthias

    2010-01-01

    Generally, older adults perform worse than younger adults in complex working memory span tasks. So far, it is unclear which processes mainly contribute to age-related differences in working memory span. The aim of the present study was to investigate age effects and the roles of proactive and coactive interference in a recognition-based version of the operation span task. Younger and older adults performed standard versions and distracter versions of the operation span task. At retrieval, participants had to recognize target words in word lists containing targets as well as proactive and/or coactive interference-related lures. Results show that, overall, younger adults outperformed older adults in the recognition of target words. Furthermore, analyses of error types indicate that, while younger adults were only affected by simultaneously presented distracter words, older adults had difficulties with both proactive and coactive interference. Results suggest that age effects in complex span tasks may not be mainly due to retrieval deficits in old age. Copyright 2009 S. Karger AG, Basel.

  9. Training through gametherapy promotes coactivation of the pelvic floor and abdominal muscles in young women, nulliparous and continents

    Directory of Open Access Journals (Sweden)

    Valeria Regina Silva

    Full Text Available ABSTRACT Introduction and objectives: Several studies have been investigated co-activation can enhance the effectveness of PFM training protocols allowing preventive and therapeutic goals in pelvic floor dysfunctions. The objective of the present study was to investigate if an abdominal-pelvic protocol of training (APT using gametherapy would allow co-activation of PFM and transversus abdominis/oblique internal (TrA/OI muscles. Patients and methods: Twenty-five nulliparous, continent, young females, with median age 24.76 (±3.76 years were evaluated using digital palpation (DP of PFM and surface electromyography of PFM and TrA/OI simultaneously, during maximal voluntary contraction (MVC, alternating PFM and TrA/OI contraction requests. All women participated on a supervised program of APT using gametherapy, that included exercises of pelvic mobilization associated to contraction of TrA/OI muscles oriented by virtual games, for 30 minutes, three times a week, in a total of 10 sessions. Electromyographic data were processed and analyzed by ANOVA - analysis of variance. Results: When MVC of TrA/OI was solicited, it was observed simultaneous increase of electromyographic activity of PFM (p=0.001 following ATP. However, EMG activity did not change significantly during MVC of PFM. Conclusion: Training using gametherapy allowed better co-activation of pelvic floor muscles in response to contraction of TrA, in young nulliparous and continent women.

  10. Regular endurance training reduces the exercise induced HIF-1alpha and HIF-2alpha mRNA expression in human skeletal muscle in normoxic conditions

    DEFF Research Database (Denmark)

    Lundby, Carsten; Gassmann, Max; Pilegaard, Henriette

    2005-01-01

    and 2 (HIFs) are clearly related heterodimeric transcription factors that consist of an oxygen-depended alpha-subunit and a constitutive beta-subunit. With hypoxic exposure, HIF-1alpha and HIF-2alpha protein are stabilized. Upon heterodimerization, HIFs induce the transcription of a variety of genes......Regular exercise induces a variety of adaptive responses that enhance the oxidative and metabolic capacity of human skeletal muscle. Although the physiological adjustments of regular exercise have been known for decades, the underlying mechanisms are still unclear. The hypoxia inducible factors 1...... including erythropoietin (EPO), transferrin and its receptor, as well as vascular endothelial growth factor (VEGF) and its receptor. Considering that several of these genes are also induced with exercise, we tested the hypothesis that the mRNA level of HIF-1alpha and HIF-2alpha subunits increases...

  11. The upregulation of receptor activator NF-kappaB ligand expression by interleukin-1alpha and Porphyromonas endodontalis in human osteoblastic cells.

    Science.gov (United States)

    Chen, S-C; Huang, F-M; Lee, S-S; Li, M-Z; Chang, Y-C

    2009-04-01

    To investigate the receptor activator of nuclear factor-kappa B (NF-kappaB) ligand (RANKL) in osteoblastic cells stimulated with inflammatory mediators. The expression of RANKL in human osteoblastic cell line U2OS stimulated by pro-inflammatory cytokine interleukin (IL)-1alpha and black-pigmented bacteria Porphyromonas endodontalis was investigated by Western blot and enzyme-linked immunosorbent assay (ELISA). The significance of the results obtained from control and treated groups was statistically analysed by the paired Student's t-test. IL-1alpha was found to upregulate RANKL production in U2OS cells (P endodontalis also increased RANKL expression in U2OS cells after 4-h incubation period demonstrated by Western blot and ELISA (P endodontalis may be involved in developing apical periodontitis through the stimulation of RANKL production.

  12. Downregulation of a tumor suppressor RECK by hypoxia through recruitment of HDAC1 and HIF-1alpha to reverse HRE site in the promoter.

    Science.gov (United States)

    Lee, Kyung Ju; Lee, Kwang Youl; Lee, You Mie

    2010-05-01

    Reversion-inducing cysteine-rich protein with Kazal motifs (RECK) is a tumor suppressor and the suppression of RECK is induced by Ras or Her-2/neu oncogenes. However, regulation of RECK under hypoxic microenvironment is largely unknown. Here, we identified that hypoxia significantly downregulates RECK mRNA and protein expression using semiquantitative RT-PCR, real-time RT-PCR and western blot analysis. This repression was reversed by the HDAC inhibitor, trichostatin A (TSA) and HIF-1 inhibitor, YC-1. Hypoxia-induced downregulation of RECK was abolished by knockdown of HDAC1 and HIF-1alpha with respective small interfering RNAs (siRNAs), whereas overexpression of HDAC1 and HIF-1alpha suppressed RECK expression similar to the level under hypoxic conditions. Transfection of a deletion mutant of the second reverse HRE (rHRE2, -2345 to -2333) site of RECK promoter completely removed RECK suppression under hypoxia, indicating that the rHRE2 site is responsible for the inhibition of RECK. Chromatin immunoprecipitation and DNA affinity precipitation assays demonstrated that HDAC1 and HIF-1alpha were recruited to the rHRE2 region of RECK promoter under hypoxic conditions, but the treatment of TSA or YC-1 inhibited their binding to the rHRE2 site. Moreover, TSA and YC-1 inhibited hypoxia-induced cancer cell migration, invasion and MMPs secretion. Taken together, we can conclude that hypoxia induces RECK downregulation through the recruitment of HDAC1 and HIF-1alpha to the rHRE2 site in the promoter and the inhibition of hypoxic RECK silencing would be a therapeutic and preventive target for early tumorigenesis. Copyright 2010 Elsevier B.V. All rights reserved.

  13. Differential Effects of Self-Reported Lifetime Marijuana Use on Interleukin-1 Alpha and Tumor Necrosis Factor in African American Adults

    OpenAIRE

    Keen, Larry; Turner, Arlener D.; Callender, Clive; Campbell, Alfonso

    2015-01-01

    It is unknown how lifetime marijuana use affects different proinflammatory cytokines. The purpose of the current study is to explore potential differential effects of lifetime marijuana use on interleukin-1 alpha (IL-1α) and tumor necrosis factor (TNF) in a community based sample. Participants included 168 African American adults (51% female, median age= 47 years). Upon study entry, blood was drawn and the participants completed questions regarding illicit drug use history whose answers were ...

  14. Modulation of renal Ca2+ transport protein genes by dietary Ca2+ and 1,25-dihydroxyvitamin D3 in 25-hydroxyvitamin D3-1alpha-hydroxylase knockout mice.

    NARCIS (Netherlands)

    Hoenderop, J.G.J.; Dardenne, O.; Abel, M. van; Kemp, J.W.C.M. van der; Os, C.H. van; Arnaud, R. St.; Bindels, R.J.M.

    2002-01-01

    Pseudovitamin D-deficiency rickets (PDDR) is an autosomal disease characterized by hyperparathyroidism, rickets, and undetectable levels of 1,25-dihydroxyvitaminD3 (1,25(OH)2D3). Mice in which the 25-hydroxyvitamin D3-1alpha-hydroxylase (1alpha-OHase) gene was inactivated presented the same clinical

  15. Anticytokine treatment of established type II collagen-induced arthritis in DBA/1 mice: a comparative study using anti-TNFalpha, anti-IL-1alpha/beta and IL-1Ra.

    NARCIS (Netherlands)

    Joosten, L.A.B.; Helsen, M.M.A.; Loo, F.A.J. van de; Berg, W.B. van den

    2008-01-01

    OBJECTIVE: To examine the role of tumor necrosis factor alpha (TNF alpha), interleukin-1 alpha (IL-1 alpha), and IL-1 beta in collagen-induced arthritis (CIA), immediately after onset and during the phase of established arthritis. METHODS: Male DBA/1 mice with collagen-induced arthritis were treated

  16. Studies of the Ala/Val98 polymorphism of the hepatocyte nuclear factor-1alpha gene and the relationship to beta-cell function during an OGTT in glucose-tolerant women with and without previous gestational diabetes mellitus

    DEFF Research Database (Denmark)

    Lauenborg, J; Damm, P; Ek, J

    2004-01-01

    In pregnancies complicated by gestational diabetes mellitus (GDM) an increased demand for insulin is not met due to beta-cell dysfunction. An Ala/Val polymorphism at codon 98 of the hepatocyte nuclear factor-1alpha (HNF-1alpha) gene has been associated with decreased serum insulin and C-peptide r...

  17. Atrial natriuretic peptide regulates lipid mobilization and oxygen consumption in human adipocytes by activating AMPK

    Energy Technology Data Exchange (ETDEWEB)

    Souza, Sandra C. [Translational Sciences - Translational Medicine, Novartis Institutes for Biomedical Research, Inc., 220 Massachusetts Avenue, Cambridge, MA 02139 (United States); Chau, Mary D.L.; Yang, Qing [Cardiovascular and Metabolism Disease Area, Novartis Institutes for Biomedical Research, Inc., 100 Technology Square, Cambridge, MA 02139 (United States); Gauthier, Marie-Soleil [Department of Pathology and Laboratory Medicine, Boston University School of Medicine, Boston, MA 02140 (United States); Clairmont, Kevin B.; Wu, Zhidan; Gromada, Jesper [Cardiovascular and Metabolism Disease Area, Novartis Institutes for Biomedical Research, Inc., 100 Technology Square, Cambridge, MA 02139 (United States); Dole, William P., E-mail: bill.dole@novartis.com [Translational Sciences - Translational Medicine, Novartis Institutes for Biomedical Research, Inc., 220 Massachusetts Avenue, Cambridge, MA 02139 (United States)

    2011-07-08

    peroxisome proliferator-activated receptor-{gamma} coactivator-1{alpha} (PGC-1{alpha}) by 1.4-fold. Treatment of human adipocytes with fatty acids and tumor necrosis factor {alpha} (TNF{alpha}) induced insulin resistance and down-regulation of mitochondrial genes, which was restored by ANP treatment. These results show that ANP regulates lipid catabolism and enhances energy dissipation through AMPK activation in human adipocytes.

  18. Acceleration of the glycolytic flux by steroid receptor coactivator-2 is essential for endometrial decidualization.

    Directory of Open Access Journals (Sweden)

    Ramakrishna Kommagani

    2013-10-01

    Full Text Available Early embryo miscarriage is linked to inadequate endometrial decidualization, a cellular transformation process that enables deep blastocyst invasion into the maternal compartment. Although much of the cellular events that underpin endometrial stromal cell (ESC decidualization are well recognized, the individual gene(s and molecular pathways that drive the initiation and progression of this process remain elusive. Using a genetic mouse model and a primary human ESC culture model, we demonstrate that steroid receptor coactivator-2 (SRC-2 is indispensable for rapid steroid hormone-dependent proliferation of ESCs, a critical cell-division step which precedes ESC terminal differentiation into decidual cells. We reveal that SRC-2 is required for increasing the glycolytic flux in human ESCs, which enables rapid proliferation to occur during the early stages of the decidualization program. Specifically, SRC-2 increases the glycolytic flux through induction of 6-phosphofructo-2-kinase/fructose-2, 6-bisphosphatase 3 (PFKFB3, a major rate-limiting glycolytic enzyme. Similarly, acute treatment of mice with a small molecule inhibitor of PFKFB3 significantly suppressed the ability of these animals to exhibit an endometrial decidual response. Together, these data strongly support a conserved mechanism of action by which SRC-2 accelerates the glycolytic flux through PFKFB3 induction to provide the necessary bioenergy and biomass to meet the demands of a high proliferation rate observed in ESCs prior to their differentiation into decidual cells. Because deregulation of endometrial SRC-2 expression has been associated with common gynecological disorders of reproductive-age women, this signaling pathway, involving SRC-2 and PFKFB3, promises to offer new clinical approaches in the diagnosis and/or treatment of a non-receptive uterus in patients presenting idiopathic infertility, recurrent early pregnancy loss, or increased time to pregnancy.

  19. Steroid receptor coactivators 1 and 2 mediate fetal-to-maternal signaling that initiates parturition.

    Science.gov (United States)

    Gao, Lu; Rabbitt, Elizabeth H; Condon, Jennifer C; Renthal, Nora E; Johnston, John M; Mitsche, Matthew A; Chambon, Pierre; Xu, Jianming; O'Malley, Bert W; Mendelson, Carole R

    2015-07-01

    The precise mechanisms that lead to parturition are incompletely defined. Surfactant protein-A (SP-A), which is secreted by fetal lungs into amniotic fluid (AF) near term, likely provides a signal for parturition; however, SP-A-deficient mice have only a relatively modest delay (~12 hours) in parturition, suggesting additional factors. Here, we evaluated the contribution of steroid receptor coactivators 1 and 2 (SRC-1 and SRC-2), which upregulate SP-A transcription, to the parturition process. As mice lacking both SRC-1 and SRC-2 die at birth due to respiratory distress, we crossed double-heterozygous males and females. Parturition was severely delayed (~38 hours) in heterozygous dams harboring SRC-1/-2-deficient embryos. These mothers exhibited decreased myometrial NF-κB activation, PGF2α, and expression of contraction-associated genes; impaired luteolysis; and elevated circulating progesterone. These manifestations also occurred in WT females bearing SRC-1/-2 double-deficient embryos, indicating that a fetal-specific defect delayed labor. SP-A, as well as the enzyme lysophosphatidylcholine acyltransferase-1 (LPCAT1), required for synthesis of surfactant dipalmitoylphosphatidylcholine, and the proinflammatory glycerophospholipid platelet-activating factor (PAF) were markedly reduced in SRC-1/-2-deficient fetal lungs near term. Injection of PAF or SP-A into AF at 17.5 days post coitum enhanced uterine NF-κB activation and contractile gene expression, promoted luteolysis, and rescued delayed parturition in SRC-1/-2-deficient embryo-bearing dams. These findings reveal that fetal lungs produce signals to initiate labor when mature and that SRC-1/-2-dependent production of SP-A and PAF is crucial for this process.

  20. Autoimmune regulator is acetylated by transcription coactivator CBP/p300

    Energy Technology Data Exchange (ETDEWEB)

    Saare, Mario, E-mail: mario.saare@ut.ee [Molecular Pathology, Institute of General and Molecular Pathology, University of Tartu, 19th Ravila Str, Tartu (Estonia); Rebane, Ana [Molecular Pathology, Institute of General and Molecular Pathology, University of Tartu, 19th Ravila Str, Tartu (Estonia); SIAF, Swiss Institute of Allergy and Asthma Research, University of Zuerich, Davos (Switzerland); Rajashekar, Balaji; Vilo, Jaak [BIIT, Bioinformatics, Algorithmics and Data Mining group, Institute of Computer Science, University of Tartu, Tartu (Estonia); Peterson, Paert [Molecular Pathology, Institute of General and Molecular Pathology, University of Tartu, 19th Ravila Str, Tartu (Estonia)

    2012-08-15

    The Autoimmune Regulator (AIRE) is a regulator of transcription in the thymic medulla, where it controls the expression of a large set of peripheral-tissue specific genes. AIRE interacts with the transcriptional coactivator and acetyltransferase CBP and synergistically cooperates with it in transcriptional activation. Here, we aimed to study a possible role of AIRE acetylation in the modulation of its activity. We found that AIRE is acetylated in tissue culture cells and this acetylation is enhanced by overexpression of CBP and the CBP paralog p300. The acetylated lysines were located within nuclear localization signal and SAND domain. AIRE with mutations that mimicked acetylated K243 and K253 in the SAND domain had reduced transactivation activity and accumulated into fewer and larger nuclear bodies, whereas mutations that mimicked the unacetylated lysines were functionally similar to wild-type AIRE. Analogously to CBP, p300 localized to AIRE-containing nuclear bodies, however, the overexpression of p300 did not enhance the transcriptional activation of AIRE-regulated genes. Further studies showed that overexpression of p300 stabilized the AIRE protein. Interestingly, gene expression profiling revealed that AIRE, with mutations mimicking K243/K253 acetylation in SAND, was able to activate gene expression, although the affected genes were different and the activation level was lower from those regulated by wild-type AIRE. Our results suggest that the AIRE acetylation can influence the selection of AIRE activated genes. -- Highlights: Black-Right-Pointing-Pointer AIRE is acetylated by the acetyltransferases p300 and CBP. Black-Right-Pointing-Pointer Acetylation occurs between CARD and SAND domains and within the SAND domain. Black-Right-Pointing-Pointer Acetylation increases the size of AIRE nuclear dots. Black-Right-Pointing-Pointer Acetylation increases AIRE protein stability. Black-Right-Pointing-Pointer AIRE acetylation mimic regulates a different set of AIRE

  1. CRTC2 Is a Coactivator of GR and Couples GR and CREB in the Regulation of Hepatic Gluconeogenesis.

    Science.gov (United States)

    Hill, Micah J; Suzuki, Shigeru; Segars, James H; Kino, Tomoshige

    2016-01-01

    Glucocorticoid hormones play essential roles in the regulation of gluconeogenesis in the liver, an adaptive response that is required for the maintenance of circulating glucose levels during fasting. Glucocorticoids do this by cooperating with glucagon, which is secreted from pancreatic islets to activate the cAMP-signaling pathway in hepatocytes. The cAMP-response element-binding protein (CREB)-regulated transcription coactivator 2 (CRTC2) is a coactivator known to be specific to CREB and plays a central role in the glucagon-mediated activation of gluconeogenesis in the early phase of fasting. We show here that CRTC2 also functions as a coactivator for the glucocorticoid receptor (GR). CRTC2 strongly enhances GR-induced transcriptional activity of glucocorticoid-responsive genes. CRTC2 physically interacts with the ligand-binding domain of the GR through a region spanning amino acids 561-693. Further, CRTC2 is required for the glucocorticoid-associated cooperative mRNA expression of the glucose-6-phosphatase, a rate-limiting enzyme for hepatic gluconeogenesis, by facilitating the attraction of GR and itself to its promoter region already occupied by CREB. CRTC2 is required for the maintenance of blood glucose levels during fasting in mice by enhancing the GR transcriptional activity on both the G6p and phosphoenolpyruvate carboxykinase (Pepck) genes. Finally, CRTC2 modulates the transcriptional activity of the progesterone receptor, indicating that it may influence the transcriptional activity of other steroid/nuclear receptors. Taken together, these results reveal that CRTC2 plays an essential role in the regulation of hepatic gluconeogenesis through coordinated regulation of the glucocorticoid/GR- and glucagon/CREB-signaling pathways on the key genes G6P and PEPCK.

  2. Expression, purification, crystallization and preliminary crystallographic study of isolated modules of the mouse coactivator-associated arginine methyltransferase 1

    Energy Technology Data Exchange (ETDEWEB)

    Troffer-Charlier, Nathalie; Cura, Vincent; Hassenboehler, Pierre; Moras, Dino; Cavarelli, Jean, E-mail: cava@igbmc.u-strasbg.fr [IGBMC (Institut de Génétique et de Biologie Moléculaire et Cellulaire), Département de Biologie et Génomique Structurales, 1 Rue Laurent Fries, Illkirch, F-67404 (France); INSERM, U596, Illkirch, F-67400 (France); CNRS, UMR7104, Illkirch, F-67400 (France); Université Louis Pasteur, Faculté des Sciences de la Vie, Strasbourg, F-67000 (France)

    2007-04-01

    Isolated modules of mouse coactivator-associated arginine methyltransferase 1 encompassing the protein arginine N-methyltransferase catalytic domain have been overexpressed, purified and crystallized. X-ray diffraction data have been collected and have enabled determination of the structures by multiple isomorphous replacement using anomalous scattering. Coactivator-associated arginine methyltransferase 1 (CARM1) plays a crucial role in gene expression as a coactivator of several nuclear hormone receptors and also of non-nuclear receptor systems. Its recruitment by the transcriptional machinery induces protein methylation, leading to chromatin remodelling and gene activation. CARM1{sub 28–507} and two structural states of CARM1{sub 140–480} were expressed, purified and crystallized. Crystals of CARM1{sub 28–507} belong to space group P6{sub 2}22, with unit-cell parameters a = b = 136.0, c = 125.3 Å; they diffract to beyond 2.5 Å resolution using synchrotron radiation and contain one monomer in the asymmetric unit. The structure of CARM1{sub 28–507} was solved by multiple isomorphous replacement and anomalous scattering methods. Crystals of apo CARM1{sub 140–480} belong to space group I222, with unit-cell parameters a = 74.6, b = 99.0, c = 207.4 Å; they diffract to beyond 2.7 Å resolution and contain two monomers in the asymmetric unit. Crystals of CARM1{sub 140–480} in complex with S-adenosyl-l-homocysteine belong to space P2{sub 1}2{sub 1}2, with unit-cell parameters a = 74.6, b = 98.65, c = 206.08 Å; they diffract to beyond 2.6 Å resolution and contain four monomers in the asymmetric unit. The structures of apo and holo CARM1{sub 140–480} were solved by molecular-replacement techniques from the structure of CARM1{sub 28–507}.

  3. Reactive oxygen species-generating mitochondrial DNA mutation up-regulates hypoxia-inducible factor-1alpha gene transcription via phosphatidylinositol 3-kinase-Akt/protein kinase C/histone deacetylase pathway.

    Science.gov (United States)

    Koshikawa, Nobuko; Hayashi, Jun-Ichi; Nakagawara, Akira; Takenaga, Keizo

    2009-11-27

    Lewis lung carcinoma-derived high metastatic A11 cells constitutively overexpress hypoxia-inducible factor (HIF)-1alpha mRNA compared with low metastatic P29 cells. Because A11 cells exclusively possess a G13997A mutation in the mitochondrial NADH dehydrogenase subunit 6 (ND6) gene, we addressed here a causal relationship between the ND6 mutation and the activation of HIF-1alpha transcription, and we investigated the potential mechanism. Using trans-mitochondrial cybrids between A11 and P29 cells, we found that the ND6 mutation was directly involved in HIF-1alpha mRNA overexpression. Stimulation of HIF-1alpha transcription by the ND6 mutation was mediated by overproduction of reactive oxygen species (ROS) and subsequent activation of phosphatidylinositol 3-kinase (PI3K)-Akt and protein kinase C (PKC) signaling pathways. The up-regulation of HIF-1alpha transcription was abolished by mithramycin A, an Sp1 inhibitor, but luciferase reporter and chromatin immunoprecipitation assays indicated that Sp1 was necessary but not sufficient for HIF-1alpha mRNA overexpression in A11 cells. On the other hand, trichostatin A, a histone deacetylase (HDAC) inhibitor, markedly suppressed HIF-1alpha transcription in A11 cells. In accordance with this, HDAC activity was high in A11 cells but low in P29 cells and in A11 cells treated with the ROS scavenger ebselene, the PI3K inhibitor LY294002, and the PKC inhibitor Ro31-8220. These results suggest that the ROS-generating ND6 mutation increases HIF-1alpha transcription via the PI3K-Akt/PKC/HDAC pathway, leading to HIF-1alpha protein accumulation in hypoxic tumor cells.

  4. Cervical Muscle Strength and Muscle Coactivation During Isometric Contractions in Patients With Migraine: A Cross-Sectional Study.

    Science.gov (United States)

    Florencio, Lidiane Lima; de Oliveira, Anamaria Siriani; Carvalho, Gabriela Ferreira; Tolentino, Gabriella de Almeida; Dach, Fabiola; Bigal, Marcelo Eduardo; Fernández-de-las-Peñas, César; Bevilaqua Grossi, Débora

    2015-01-01

    This cross-sectional study investigated potential differences in cervical musculature in groups of migraine headaches vs. non-headache controls. Differences in cervical muscle strength and antagonist coactivation during maximal isometric voluntary contraction (MIVC) were analyzed between individuals with migraine and non-headache subjects and relationships between force with migraine and neck pain clinical aspects. A customized hand-held dynamometer was used to assess cervical flexion, extension, and bilateral lateral flexion strength in subjects with episodic migraine (n=31), chronic migraine (n = 21) and healthy controls (n = 31). Surface electromyography (EMG) from sternocleidomastoid, anterior scalene, and splenius capitis muscles were recorded during MIVC to evaluate antagonist coactivation. Comparison of main outcomes among groups was conducted with one-way analysis of covariance with the presence of neck pain as covariable. Correlations between peak force and clinical variables were demonstrated by Spearman's coefficient. Chronic migraine subjects exhibited lower cervical extension force (mean diff. from controls: 4.4 N/kg; mean diff from episodic migraine: 3.7 N/kg; P = .006) and spent significantly more time to generate peak force during cervical flexion (mean diff. from controls: 0.5 seconds; P = .025) and left lateral-flexion (mean diff. from controls: 0.4 seconds; mean diff. from episodic migraine: 0.5 seconds; P = .007). Both migraine groups showed significantly higher antagonist muscle coactivity of the splenius capitis muscle (mean diff. from controls: 20%MIVC, P = .03) during cervical flexion relative to healthy controls. Cervical extension peak force was moderately associated with the migraine frequency (rs: -0.30, P = .034), neck pain frequency (rs: -0.26, P = .020), and neck pain intensity (rs: -0.27, P = .012). Patients with chronic migraine exhibit altered muscle performance, took longer to reach peak of

  5. Ankle torque steadiness is related to muscle activation variability and co-activation in children with cerebral palsy

    DEFF Research Database (Denmark)

    Bandholm, Thomas; Rose, Martin; Sløk, Rikke

    2009-01-01

    The aims of this study were to: (1) investigate the significance of muscle activation variability and coactivation for the ability to perform steady submaximal ankle torque (torque steadiness) in healthy children and those with cerebral palsy (CP), and (2) assess ankle function during isometric...... contractions in those children. Fourteen children with CP who walked with equinus foot deformity and 14 healthy (control) children performed maximal and steady submaximal ankle dorsi- and plantarflexions. Dorsiflexion torque steadiness was related to agonist and antagonist muscle activation variability as well...

  6. Unbiased gene expression analysis implicates the huntingtin polyglutamine tract in extra-mitochondrial energy metabolism.

    Directory of Open Access Journals (Sweden)

    Jong-Min Lee

    2007-08-01

    Full Text Available The Huntington's disease (HD CAG repeat, encoding a polymorphic glutamine tract in huntingtin, is inversely correlated with cellular energy level, with alleles over approximately 37 repeats leading to the loss of striatal neurons. This early HD neuronal specificity can be modeled by respiratory chain inhibitor 3-nitropropionic acid (3-NP and, like 3-NP, mutant huntingtin has been proposed to directly influence the mitochondrion, via interaction or decreased PGC-1alpha expression. We have tested this hypothesis by comparing the gene expression changes due to mutant huntingtin accurately expressed in STHdh(Q111/Q111 cells with the changes produced by 3-NP treatment of wild-type striatal cells. In general, the HD mutation did not mimic 3-NP, although both produced a state of energy collapse that was mildly alleviated by the PGC-1alpha-coregulated nuclear respiratory factor 1 (Nrf-1. Moreover, unlike 3-NP, the HD CAG repeat did not significantly alter mitochondrial pathways in STHdh(Q111/Q111 cells, despite decreased Ppargc1a expression. Instead, the HD mutation enriched for processes linked to huntingtin normal function and Nf-kappaB signaling. Thus, rather than a direct impact on the mitochondrion, the polyglutamine tract may modulate some aspect of huntingtin's activity in extra-mitochondrial energy metabolism. Elucidation of this HD CAG-dependent pathway would spur efforts to achieve energy-based therapeutics in HD.

  7. Steroid receptor coactivator 1 deficiency increases MMTV-neu mediated tumor latency and differentiation specific gene expression, decreases metastasis, and inhibits response to PPAR ligands

    International Nuclear Information System (INIS)

    Han, Ji Seung; Crowe, David L

    2010-01-01

    The peroxisome proliferator activated receptor (PPAR) subgroup of the nuclear hormone receptor superfamily is activated by a variety of natural and synthetic ligands. PPARs can heterodimerize with retinoid X receptors, which have homology to other members of the nuclear receptor superfamily. Ligand binding to PPAR/RXRs results in recruitment of transcriptional coactivator proteins such as steroid receptor coactivator 1 (SRC-1) and CREB binding protein (CBP). Both SRC-1 and CBP are histone acetyltransferases, which by modifying nucleosomal histones, produce more open chromatin structure and increase transcriptional activity. Nuclear hormone receptors can recruit limiting amounts of coactivators from other transcription factor binding sites such as AP-1, thereby inhibiting the activity of AP-1 target genes. PPAR and RXR ligands have been used in experimental breast cancer therapy. The role of coactivator expression in mammary tumorigenesis and response to drug therapy has been the subject of recent studies. We examined the effects of loss of SRC-1 on MMTV-neu mediated mammary tumorigenesis. SRC-1 null mutation in mammary tumor prone mice increased the tumor latency period, reduced tumor proliferation index and metastasis, inhibited response to PPAR and RXR ligands, and induced genes involved in mammary gland differentiation. We also examined human breast cancer cell lines overexpressing SRC-1 or CBP. Coactivator overexpression increased cellular proliferation with resistance to PPAR and RXR ligands and remodeled chromatin of the proximal epidermal growth factor receptor promoter. These results indicate that histone acetyltransferases play key roles in mammary tumorigenesis and response to anti-proliferative therapies

  8. Transcriptional coactivator NT-PGC-1α promotes gluconeogenic gene expression and enhances hepatic gluconeogenesis.

    Science.gov (United States)

    Chang, Ji Suk; Jun, Hee-Jin; Park, Minsung

    2016-10-01

    The transcriptional coactivator PGC-1α plays a central role in hepatic gluconeogenesis. We previously reported that alternative splicing of the PGC-1α gene produces an additional transcript encoding the truncated protein NT-PGC-1α NT-PGC-1α is co-expressed with PGC-1α and highly induced by fasting in the liver. NT-PGC-1α regulates tissue-specific metabolism, but its role in the liver has not been investigated. Thus, the objective of this study was to determine the role of hepatic NT-PGC-1α in the regulation of gluconeogenesis. Adenovirus-mediated expression of NT-PGC-1α in primary hepatocytes strongly stimulated the expression of key gluconeogenic enzyme genes (PEPCK and G6Pase), leading to increased glucose production. To further understand NT-PGC-1α function in hepatic gluconeogenesis in vivo, we took advantage of a previously reported FL-PGC-1α -/- mouse line that lacks full-length PGC-1α (FL-PGC-1α) but retains a slightly shorter and functionally equivalent form of NT-PGC-1α (NT-PGC-1α 254 ). In FL-PGC-1α -/- mice, NT-PGC-1α 254 was induced by fasting in the liver and recruited to the promoters of PEPCK and G6Pase genes. The enrichment of NT-PGC-1α 254 at the promoters was closely associated with fasting-induced increase in PEPCK and G6Pase gene expression and efficient production of glucose from pyruvate during a pyruvate tolerance test in FL-PGC-1α -/- mice. Moreover, FL-PGC-1α -/- primary hepatocytes showed a significant increase in gluconeogenic gene expression and glucose production after treatment with dexamethasone and forskolin, suggesting that NT-PGC-1α 254 is sufficient to stimulate the gluconeogenic program in the absence of FL-PGC-1α Collectively, our findings highlight the role of hepatic NT-PGC-1α in stimulating gluconeogenic gene expression and glucose production. © 2016 The Authors. Physiological Reports published by Wiley Periodicals, Inc. on behalf of the American Physiological Society and The Physiological Society.

  9. Synergistic co-activation increases the extent of mechanical interaction between rat ankle plantar-flexors

    Directory of Open Access Journals (Sweden)

    Chris Tijs

    2016-09-01

    Full Text Available Force transmission between rat ankle plantar-flexors has been found for physiological muscle lengths and relative positions, but only with all muscles maximally activated. The aims of this study were to assess intermuscular mechanical interactions between ankle plantar-flexors during (i fully passive conditions, (ii excitation of soleus (SO, (iii excitation of lateral gastrocnemius (LG, and (iv during co-activation of SO and LG (SO&LG. We assessed effects of proximal lengthening of LG and plantaris (PL muscles (i.e. simulating knee extension on forces exerted at the distal SO tendon (FSO and on the force difference between the proximal and distal LG+PL tendons (ΔFLG+PL of the rat. LG+PL lengthening increased FSO to a larger extent (p=0.017 during LG excitation (0.0026 N/mm than during fully passive conditions (0.0009 N/mm. Changes in FSO in response to LG+PL lengthening were lower (p=0.002 during SO only excitation (0.0056 N/mm than during SO&LG excitation (0.0101 N/mm. LG+PL lengthening changed ∆FLG+PL to a larger extent (p=0.007 during SO excitation (0.0211 N/mm than during fully passive conditions (0.0157 N/mm. In contrast, changes in ∆FLG+PL in response to LG+PL lengthening during LG excitation (0.0331 N/mm were similar (p=0.161 to that during SO&LG excitation (0.0370 N/mm. In all conditions, changes of FSO were lower than those of ∆FLG+PL. This indicates that muscle forces were transmitted not only between LG+PL and SO, but also between LG+PL and other surrounding structures. In addition, epimuscular myofascial force transmission between rat ankle plantar-flexors was enhanced by muscle activation. However, the magnitude of this interaction was limited.

  10. The inhibitory effect of an extract of Sanguisorba officinalis L. on ultraviolet B-induced pigmentation via the suppression of endothelin-converting enzyme-1{alpha}

    Energy Technology Data Exchange (ETDEWEB)

    Hachiya, Akira; Kobayashi, Akemi; Ohuchi, Atsushi; Kitahara, Takashi; Takema, Yoshinori [Kao Biological Science Lab., Ichikai, Tochigi (Japan)

    2001-06-01

    Endothelin-1 (ET-1) has been reported to be expressed in human epidermis at both the gene and protein levels. ET-1 plays a pivotal role in ultraviolet B (UVB)-induced pigmentation due to its accentuated secretion after UVB irradiation and its function as a mitogen and as a melanogen for human melanocytes. We have recently found that endothelin-converting enzyme (ECE)-1{alpha} plays a constitutive role in the secretion of ET-1 by human keratinocytes and that an extract of Sanguisorba officinalis L. inhibits ECE activity in human endothelial cells, which predominantly express ECE-1{alpha}. In this report, to clarify the potential use of this botanical extract as a whitening agent, we examined whether this extract inhibits UVB-induced pigmentation in vivo. When this extract was applied to human keratinocytes after UVB irradiation, secretion of ET-1 by those cells was reduced, and this was accompanied by a concomitant increase in the secretion of inactive precursor Big endothelin-1. When hairless mice were exposed to UVB light and were treated with the extract, it suppressed the induction of ET-1 in the UVB-irradiated epidermis. In the course of UVB-induced pigmentation of brownish guinea pig skin, this extract significantly diminished pigmentation in UVB-exposed areas. These findings indicate that ECE-1{alpha} in keratinocytes plays a pivotal role in the induction of pigmentation following UVB irradiation and that an extract of S. officinalis, which inhibits ET-1 production in human keratinocytes, is a good ingredient for a whitening agent. (author)

  11. Expression of SCM-1alpha/lymphotactin and SCM-1beta in natural killer cells is upregulated by IL-2 and IL-12.

    Science.gov (United States)

    Hennemann, B; Tam, Y K; Tonn, T; Klingemann, H G

    1999-07-01

    Recruitment of lymphocytes is an important feature of the host immune response against pathogens. However, the mechanisms by which lymphocytes are attracted are not yet fully understood. Recently, the cDNA of a lymphocyte-specific chemokine, lymphotactin (Lptn), was isolated from murine and human T cells and was also found to be expressed in murine NK cells and human NK cell clones. This study investigated the influence of interleukin (IL)-2 and IL-12 on the expression of Lptn, also known as SCM (single cysteine motif)-1alpha, and SCM-1beta, a 97% homolog of Lptn, in freshly isolated human NK cells and the human NK cell line NK-92. Northern blot analysis and RT-PCR confirmed that nonactivated human NK cells expressed both genes at low level. After activation with IL-2 or IL-12, the expression of both Lptn and SCM-1beta was upregulated within hours. NK-92 cells maintained in medium supplemented with IL-2 constitutively expressed SCM-1 mRNA. However, after 24 h of IL-2 starvation and subsequent culturing at various IL-2 concentrations, the expression of Lptn/SCM-1alpha was upregulated in a dose-dependent manner, whereas the expression of SCM-1beta remained consistently high. These observations indicate that NK cells, in addition to T lymphocytes, express Lptn/SCM-1alpha and SCM-1beta after cytokine activation. The upregulation of these chemokines in NK cells on activation likely acts to increase the number of effector cells reaching the site of an immune response such as inflammation.

  12. Reoxygenation of human coronary smooth muscle cells suppresses HIF-1{alpha} gene expression and augments radiation-induced growth delay and apoptosis

    Energy Technology Data Exchange (ETDEWEB)

    Grumann, T.; Arab, A.; Bode, C.; Hehrlein, C. [Dept. of Cardiology, Univ. Clinic of Freiburg (Germany); Guttenberger, R. [Dept. of Radiotherapy, Univ. Clinic of Freiburg (Germany)

    2006-01-01

    Background and Purpose: Catheter-based coronary brachytherapy with {beta}- and {gamma}-radiation is an evidence-based method to prevent restenosis after percutaneous transluminal coronary angioplasty (PTCA) and stent implantation, but the outcome may be PTCA are hypoxic. A lack of oxygen decreases the effect of low LET (linear energy transfer) irradiation. The authors assumed that reoxygenation of hypoxic human coronary smooth muscle cells (HCSMCs) improves the results of coronary brachytherapy. The expression of hypoxia-inducible factor 1{alpha} (HIF-1{alpha}) gene, and the rates of growth and apoptosis of hypoxic and reoxygenated HCSMCs after {gamma}-iradiation were therefore analyzed. Material and Methods: An in vitro model of megacolonies of HCSMCs was developed. After exposure to chronic hypoxia the HCSMCs were irradiated with graded doses of 2, 4, 8, and 16 Gy using a {sup 60}Co source either under hypoxia (pO{sub 2}<3 mmHg) or after reoxygenation (pO{sub 2}{approx}150 mmHg). RT-PCR (reverse transcription-polymerase chain reaction) analysis was used to quantify HIF-1{alpha} gene expression and the growth of HCSMC megacolonies was measured serially. The oxygen enhancement ratio (OER) was calculate from the specific growth delay. Apoptosis of HCSMCs was quantified by counting cells with specific DNA strand breaks using the TUNEL assy. Results: HIF-1{alpha} gene expression was markedly suppressed in reoxygenated cells versus hypoxic cells 30 min after {gamma}-irradiation at all radiation doses (158{+-}46% vs. 1,675{+-}1,211%; p<0.01). Apoptosis was markedly increased in reoxygenated HCSMCs. The OER was 1.8(95% CI[confidence interval]1.3-2.4). Therefore, reoxygenated HCSMCs require 44% less radiation dose to achieve the equivalent biological radiation effect compared to hypoxic HCSMCs. Conclusion: Reoxygenation of coronary smooth muscle cells should be considered an option to increase efficacy of coronary brachytherapy. This could be used to reduce radiation dose

  13. The PGC-1 coactivators promote an anti-inflammatory environment in skeletal muscle in vivo

    International Nuclear Information System (INIS)

    Eisele, Petra Sabine; Furrer, Regula; Beer, Markus; Handschin, Christoph

    2015-01-01

    The peroxisome proliferator-activated receptor γ coactivator 1α (PGC-1α) is abundantly expressed in trained muscles and regulates muscle adaptation to endurance exercise. Inversely, mice lacking a functional PGC-1α allele in muscle exhibit reduced muscle functionality and increased inflammation. In isolated muscle cells, PGC-1α and the related PGC-1β counteract the induction of inflammation by reducing the activity of the nuclear factor κB (NFκB). We now tested the effects of these metabolic regulators on inflammatory reactions in muscle tissue of control and muscle-specific PGC-1α/-1β transgenic mice in vivo in the basal state as well as after an acute inflammatory insult. Surprisingly, we observed a PGC-1-dependent alteration of the cytokine profile characterized by an increase in anti-inflammatory factors and a strong suppression of the pro-inflammatory interleukin 12 (IL-12). In conclusion, the anti-inflammatory environment in muscle that is promoted by the PGC-1s might contribute to the beneficial effects of these coactivators on muscle function and provides a molecular link underlying the tight mutual regulation of metabolism and inflammation. - Highlights: • Muscle PGC-1s are insufficient to prevent acute systemic inflammation. • The muscle PGC-1s however promote a local anti-inflammatory environment. • This anti-inflammatory environment could contribute to the therapeutic effect of the PGC-1s

  14. The PGC-1 coactivators promote an anti-inflammatory environment in skeletal muscle in vivo

    Energy Technology Data Exchange (ETDEWEB)

    Eisele, Petra Sabine [Biozentrum, Division of Pharmacology/Neurobiology, University of Basel, CH-4056 Basel (Switzerland); Zurich Center for Integrative Human Physiology, University of Zurich, CH-8057 Zurich (Switzerland); Furrer, Regula; Beer, Markus [Biozentrum, Division of Pharmacology/Neurobiology, University of Basel, CH-4056 Basel (Switzerland); Handschin, Christoph, E-mail: christoph.handschin@unibas.ch [Biozentrum, Division of Pharmacology/Neurobiology, University of Basel, CH-4056 Basel (Switzerland); Zurich Center for Integrative Human Physiology, University of Zurich, CH-8057 Zurich (Switzerland)

    2015-08-28

    The peroxisome proliferator-activated receptor γ coactivator 1α (PGC-1α) is abundantly expressed in trained muscles and regulates muscle adaptation to endurance exercise. Inversely, mice lacking a functional PGC-1α allele in muscle exhibit reduced muscle functionality and increased inflammation. In isolated muscle cells, PGC-1α and the related PGC-1β counteract the induction of inflammation by reducing the activity of the nuclear factor κB (NFκB). We now tested the effects of these metabolic regulators on inflammatory reactions in muscle tissue of control and muscle-specific PGC-1α/-1β transgenic mice in vivo in the basal state as well as after an acute inflammatory insult. Surprisingly, we observed a PGC-1-dependent alteration of the cytokine profile characterized by an increase in anti-inflammatory factors and a strong suppression of the pro-inflammatory interleukin 12 (IL-12). In conclusion, the anti-inflammatory environment in muscle that is promoted by the PGC-1s might contribute to the beneficial effects of these coactivators on muscle function and provides a molecular link underlying the tight mutual regulation of metabolism and inflammation. - Highlights: • Muscle PGC-1s are insufficient to prevent acute systemic inflammation. • The muscle PGC-1s however promote a local anti-inflammatory environment. • This anti-inflammatory environment could contribute to the therapeutic effect of the PGC-1s.

  15. Analysis of PGC-1α variants Gly482Ser and Thr612Met concerning their PPARγ2-coactivation function

    International Nuclear Information System (INIS)

    Nitz, Inke; Ewert, Agnes; Klapper, Maja; Doering, Frank

    2007-01-01

    Peroxisome proliferator-activated receptor-γ coactivator-1α (PGC-1α) is a cofactor involved in adaptive thermogenesis, fatty acid oxidation, and gluconeogenesis. Dysfunctions of this protein are likely to contribute to the development of obesity and the metabolic syndrome. This is in part but not definitely confirmed by results of population studies. The aim of this study was to investigate if common genetic variants rs8192678 (Gly482Ser) and rs3736265 (Thr612Met) in the PGC-1α gene lead to a functional consequence in cofactor activity using peroxisome proliferator-activated receptor-γ 2 (PPARγ2) as interacting transcription factor. Reporter gene assays in HepG2 cells with wildtype and mutant proteins of both PGC1α and PPARγ2 (Pro12Ala, rs1801282) using the acyl-CoA-binding protein (ACBP) promoter showed no difference in coactivator activity. This is First study implicating that the Gly482Ser and Thr612Met polymorphisms in PGC-1α and Pro12Ala polymorphism in PPARγ2 do not affect the functional integrity of these proteins

  16. Nontranscriptional regulation of SYK by the coactivator OCA-B is required at multiple stages of B cell development.

    Science.gov (United States)

    Siegel, Rachael; Kim, Unkyu; Patke, Alina; Yu, Xin; Ren, Xiaodi; Tarakhovsky, Alexander; Roeder, Robert G

    2006-05-19

    OCA-B was originally identified as a nuclear transcriptional coactivator that is essential for antigen-driven immune responses. The later identification of a membrane bound, myristoylated form of OCA-B suggested additional, unique functions in B cell signaling pathways. This study has shown that OCA-B also functions in the pre-B1-to-pre-B2 cell transition and, most surprisingly, that it directly interacts with SYK, a tyrosine kinase critical for pre-BCR and BCR signaling. This unprecedented type of interaction-a transcriptional coactivator with a signaling kinase-occurs in the cytoplasm and directly regulates SYK stability. This study indicates that OCA-B is required for pre-BCR and BCR signaling at multiple stages of B cell development through its nontranscriptional regulation of SYK. Combined with the deregulation of OCA-B target genes, this may help explain the multitude of defects observed in B cell development and immune responses of Oca-b-/- mice.

  17. Computational stability of human knee joint at early stance in Gait: Effects of muscle coactivity and anterior cruciate ligament deficiency.

    Science.gov (United States)

    Sharifi, M; Shirazi-Adl, A; Marouane, H

    2017-10-03

    As one of the most complex and vulnerable structures of body, the human knee joint should maintain dynamic equilibrium and stability in occupational and recreational activities. The evaluation of its stability and factors affecting it is vital in performance evaluation/enhancement, injury prevention and treatment managements. Knee stability often manifests itself by pain, hypermobility and giving-way sensations and is usually assessed by the passive joint laxity tests. Mechanical stability of both the human knee joint and the lower extremity at early stance periods of gait (0% and 5%) were quantified here for the first time using a hybrid musculoskeletal model of the lower extremity. The roles of muscle coactivity, simulated by setting minimum muscle activation at 0-10% levels and ACL deficiency, simulated by reducing ACL resistance by up to 85%, on the stability margin as well as joint biomechanics (contact/muscle/ligament forces) were investigated. Dynamic stability was analyzed using both linear buckling and perturbation approaches at the final deformed configurations in gait. The knee joint was much more stable at 0% stance than at 5% due to smaller ground reaction and contact forces. Muscle coactivity, when at lower intensities (knee joint at the heel strike. It also markedly diminishes forces in lateral hamstrings (by up to 39%) and contact forces on the lateral plateau (by up to 17%). Current work emphasizes the need for quantification of the lower extremity stability margin in gait. Copyright © 2017 Elsevier Ltd. All rights reserved.

  18. The novel hypoxic cytotoxin, TX-2098 has antitumor effect in pancreatic cancer; possible mechanism through inhibiting VEGF and hypoxia inducible factor-1{alpha} targeted gene expression

    Energy Technology Data Exchange (ETDEWEB)

    Miyake, Kotaro, E-mail: hif.panc@gmail.com [Department of Surgery, Institute of Health Biosciences, The University of Tokushima Graduate School, Tokushima 770-8503 (Japan); Nishioka, Masanori; Imura, Satoru; Batmunkh, Erdenebulgan [Department of Surgery, Institute of Health Biosciences, The University of Tokushima Graduate School, Tokushima 770-8503 (Japan); Uto, Yoshihiro [Department of Biological Science and Technology, Institute of Socio Technosciences, The University of Tokushima Graduate School, Tokushima 770-8503 (Japan); Nagasawa, Hideko [Laboratory of Pharmaceutical and Medicinal Chemistry, Gifu Pharmaceutical University, Gifu 501-1196 (Japan); Hori, Hitoshi [Department of Biological Science and Technology, Institute of Socio Technosciences, The University of Tokushima Graduate School, Tokushima 770-8503 (Japan); Shimada, Mitsuo [Department of Surgery, Institute of Health Biosciences, The University of Tokushima Graduate School, Tokushima 770-8503 (Japan)

    2012-08-01

    Tumor hypoxia has been considered to be a potential therapeutic target, because hypoxia is a common feature of solid tumors and is associated with their malignant phenotype. In the present study, we investigated the antitumor effect of a novel hypoxic cytotoxin, 3-[2-hydroxyethyl(methyl)amino]-2-quinoxalinecarbonitrile 1,4-dioxide (TX-2098) in inhibiting the expression of hypoxia inducible factor-1{alpha} (HIF-1{alpha}), and consequently vascular endothelial cell growth factor (VEGF) expression in pancreatic cancer. The antitumor effects of TX-2098 under hypoxia were tested against various human pancreatic cancer cell lines using WST-8 assay. VEGF protein induced pancreatic cancer was determined on cell-free supernatant by ELISA. Moreover, nude mice bearing subcutaneously (s.c.) or orthotopically implanted human SUIT-2 were treated with TX-2098. Tumor volume, survival and expression of HIF-1 and associated molecules were evaluated in treatment versus control groups. In vitro, TX-2098 inhibited the proliferation of various pancreatic cancer cell lines. In s.c model, tumors from nude mice injected with pancreatic cancer cells and treated with TX-2098 showed significant reductions in volume (P < 0.01 versus control). Quantitative real-time reverse transcription-PCR analysis revealed that TX-2098 significantly inhibited mRNA expression of the HIF-1 associated molecules, VEGF, glucose transporter 1 and Aldolase A (P < 0.01 versus control). These treatments also prolong the survival in orthotopic models. These results suggest that the effect of TX-2098 in pancreatic cancer might be correlated with the expression of VEGF and HIF-1 targeted molecules. -- Highlights: Black-Right-Pointing-Pointer We designed and synthesized novel hypoxic cytoxin, TX-2098. Black-Right-Pointing-Pointer TX-2098 inhibited the proliferation of human pancreatic cancer cells than TPZ. Black-Right-Pointing-Pointer TX-2098 reduced VEGF protein level than TPZ. Black-Right-Pointing-Pointer TX-2098

  19. Drosophila MBF1 is a co-activator for Tracheae Defective and contributes to the formation of tracheal and nervous systems

    Czech Academy of Sciences Publication Activity Database

    Liu, Q. X.; Jindra, Marek; Ueda, H.; Hiromi, Y.; Hirose, S.

    2003-01-01

    Roč. 130, - (2003), s. 719-728 ISSN 0950-1991 R&D Projects: GA ČR GA204/00/0811 Institutional research plan: CEZ:AV0Z5007907 Keywords : TDF * MBF1 * co-activator Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 7.663, year: 2003

  20. Specific inhibition of hypoxia-inducible factor (HIF)-1 alpha activation and of vascular endothelial growth factor (VEGF) production by flavonoids.

    Science.gov (United States)

    Hasebe, Yuki; Egawa, Kiyoshi; Yamazaki, Yoko; Kunimoto, Setsuko; Hirai, Yasuaki; Ida, Yoshiteru; Nose, Kiyoshi

    2003-10-01

    Screening using a reporter under the control of the hypoxia-response element (HRE) identified several flavonoids and homoisoflavonoids that inhibit the activation of HRE under hypoxic conditions. Among various compounds, isorhamnetin, luteolin, quercetin, and methyl ophiopogonanone B (MOB) were effective at 3 to 9 microg/ml in inhibiting the reporter activity. The expression of vascular endothelial growth factor (VEGF) mRNA during hypoxia was also inhibited by MOB in HepG2 cells, but the effective doses were 10 to 20 microg/ml. MOB caused destabilization of hypoxia-inducible factor (HIF)-1alpha, as revealed by Western blotting, that was dependent on proteasome activity and the tumor suppressor, p53. The tubular formation and migration of human umbilical vein endothelial cells was also inhibited by MOB. MOB is expected to act as an inhibitor of angiogenesis.

  1. Production of macrophage inflammatory protein (MIP)-1alpha and MIP-1beta by human polymorphonuclear neutrophils stimulated with Porphyromonas endodontalis lipopolysaccharide.

    Science.gov (United States)

    Ko, Hyun Jung; Lim, Sung Sam

    2002-11-01

    This study was undertaken to investigate the capacity of polymorphonuclear neutrophils (PMNs) to secrete Macrophage Inflammatory Protein (MIP)-1alpha and MIP-1beta after stimulation with Porphyromonas endodontalis lipopolysaccharide (LPS). Escherichia coli LPS was used as a positive control. Venous blood was collected and PMNs were isolated from healthy volunteers. Cells were cultured with various concentrations of LPS for different periods of time. Cell supernatants were assayed by enzyme-linked immunosorbent assay. The levels of chemokine secretion in PMNs stimulated with each LPS were found to be significantly higher than in the unstimulated control cells (p endodontalis LPS. These findings demonstrated that P. endodontalis LPS is capable of stimulating PMNs to produce chemotactic cytokines and suggested that PMNs stimulated with P. endodontalis LPS may play a crucial role in the inflammatory and immunopathological reactions of pulpal and periapical diseases.

  2. Differential regulation of the PGC family of genes in a mouse model of Staphylococcus aureus sepsis.

    Directory of Open Access Journals (Sweden)

    Timothy E Sweeney

    2010-07-01

    Full Text Available The PGC family of transcriptional co-activators (PGC-1alpha [Ppargc1a], PGC-1beta [Ppargc1b], and PRC [Pprc] coordinates the upregulation of mitochondrial biogenesis, and Ppargc1a is known to be activated in response to mitochondrial damage in sepsis. Therefore, we postulated that the PGC family is regulated by the innate immune system. We investigated whether mitochondrial biogenesis and PGC gene expression are disrupted in an established model of Staphylococcus aureus sepsis both in mice with impaired innate immune function (TLR2-/- and TLR4-/- and in wild-type controls. We found an early up-regulation of Ppargc1a and Ppargc1b post-infection (at 6 h in WT mice, but the expression of both genes was concordantly dysregulated in TLR2-/- mice (no increase at 6 h and in TLR4-/- mice (amplified at 6 h. However, the third family member, PRC, was regulated differently, and its expression increased significantly at 24 h in all three mouse strains (WT, TLR2-/-, and TLR4-/-. In silico analyses showed that Ppargc1a and Ppargc1b share binding sites for microRNA mmu-mir-202-3p. Thus, miRNA-mediated post-transcriptional mRNA degradation could account for the failure to increase the expression of both genes in TLR2-/- mice. The expression of mmu-mir-202-3p was measured by real-time PCR and found to be significantly increased in TLR2-/- but not in WT or TLR4-/- mice. In addition, it was found that mir-202-3p functionally decreases Ppargc1a mRNA in vitro. Thus, both innate immune signaling through the TLRs and mir-202-3p-mediated mRNA degradation are implicated in the co-regulation of Ppargc1a and Ppargc1b during inflammation. Moreover, the identification of mir-202-3p as a potential factor for Ppargc1a and Ppargc1b repression in acute inflammation may open new avenues for mitochondrial research and, potentially, therapy.

  3. Rapid detection of hypoxia-inducible factor-1-active tumours: pretargeted imaging with a protein degrading in a mechanism similar to hypoxia-inducible factor-1{alpha}

    Energy Technology Data Exchange (ETDEWEB)

    Ueda, Masashi [Kyoto University, Radioisotopes Research Laboratory, Kyoto University Hospital, Faculty of Medicine, Kyoto (Japan); Kyoto University, Department of Patho-Functional Bioanalysis, Graduate School of Pharmaceutical Sciences, Kyoto (Japan); Kudo, Takashi; Konishi, Hiroaki; Miyano, Azusa; Ono, Masahiro; Saji, Hideo [Kyoto University, Department of Patho-Functional Bioanalysis, Graduate School of Pharmaceutical Sciences, Kyoto (Japan); Kuge, Yuji [Kyoto University, Department of Patho-Functional Bioanalysis, Graduate School of Pharmaceutical Sciences, Kyoto (Japan); Hokkaido University, Central Institute of Isotope Science, Sapporo (Japan); Mukai, Takahiro [Kyushu University, Department of Biomolecular Recognition Chemistry, Graduate School of Pharmaceutical Sciences, Fukuoka (Japan); Tanaka, Shotaro; Kizaka-Kondoh, Shinae; Hiraoka, Masahiro [Kyoto University, Department of Radiation Oncology and Image-applied Therapy, Graduate School of Medicine, Kyoto (Japan)

    2010-08-15

    Hypoxia-inducible factor-1 (HIF-1) plays an important role in malignant tumour progression. For the imaging of HIF-1-active tumours, we previously developed a protein, POS, which is effectively delivered to and selectively stabilized in HIF-1-active cells, and a radioiodinated biotin derivative, (3-{sup 123}I-iodobenzoyl)norbiotinamide ({sup 123}I-IBB), which can bind to the streptavidin moiety of POS. In this study, we aimed to investigate the feasibility of the pretargeting method using POS and {sup 123}I-IBB for rapid imaging of HIF-1-active tumours. Tumour-implanted mice were pretargeted with POS. After 24 h, {sup 125}I-IBB was administered and subsequently, the biodistribution of radioactivity was investigated at several time points. In vivo planar imaging, comparison between {sup 125}I-IBB accumulation and HIF-1 transcriptional activity, and autoradiography were performed at 6 h after the administration of {sup 125}I-IBB. The same sections that were used in autoradiographic analysis were subjected to HIF-1{alpha} immunohistochemistry. {sup 125}I-IBB accumulation was observed in tumours of mice pretargeted with POS (1.6%ID/g at 6 h). This result is comparable to the data derived from {sup 125}I-IBB-conjugated POS-treated mice (1.4%ID/g at 24 h). In vivo planar imaging provided clear tumour images. The tumoral accumulation of {sup 125}I-IBB significantly correlated with HIF-1-dependent luciferase bioluminescence (R=0.84, p<0.01). The intratumoral distribution of {sup 125}I-IBB was heterogeneous and was significantly correlated with HIF-1{alpha}-positive regions (R=0.58, p<0.0001). POS pretargeting with {sup 123}I-IBB is a useful technique in the rapid imaging and detection of HIF-1-active regions in tumours. (orig.)

  4. Integrin {alpha}{beta}1, {alpha}{sub v}{beta}, {alpha}{sub 6}{beta} effectors p130Cas, Src and talin regulate carcinoma invasion and chemoresistance

    Energy Technology Data Exchange (ETDEWEB)

    Sansing, Hope A. [Department of Oral and Craniofacial Biology, Louisiana State University Health Sciences Center-New Orleans, School of Dentistry, New Orleans, LA (United States); Sarkeshik, Ali; Yates, John R. [Department of Chemical Physiology, Scripps Research Institute, La Jolla, CA (United States); Patel, Vyomesh; Gutkind, J. Silvio [Oral and Pharyngeal Cancer Branch, National Institute of Dental and Craniofacial Research, National Institutes of Health, Bethesda, MD (United States); Yamada, Kenneth M. [Laboratory of Cell and Developmental Biology, National Institute of Dental and Craniofacial Research, National Institutes of Health, Bethesda, MD (United States); Berrier, Allison L., E-mail: allison.berrier@gmail.com [Department of Oral and Craniofacial Biology, Louisiana State University Health Sciences Center-New Orleans, School of Dentistry, New Orleans, LA (United States)

    2011-03-11

    Research highlights: {yields} Proteomics of clustered integrin {alpha}{beta}1, {alpha}{sub v}{beta}, {alpha}{sub 6}{beta} receptors in oral carcinoma. {yields} p130Cas, Dek, Src and talin regulate oral carcinoma invasion. {yields} p130Cas, talin, Src and zyxin regulate oral carcinoma resistance to cisplatin. -- Abstract: Ligand engagement by integrins induces receptor clustering and formation of complexes at the integrin cytoplasmic face that controls cell signaling and cytoskeletal dynamics critical for adhesion-dependent processes. This study searches for a subset of integrin effectors that coordinates both tumor cell invasion and resistance to the chemotherapeutic drug cisplatin in oral carcinomas. Candidate integrin effectors were identified in a proteomics screen of proteins recruited to clustered integrin {alpha}{beta}1, {alpha}{sub v}{beta} or {alpha}{sub 6}{beta} receptors in oral carcinomas. Proteins with diverse functions including microtubule and actin binding proteins, and factors involved in trafficking, transcription and translation were identified in oral carcinoma integrin complexes. Knockdown of effectors in the oral carcinoma HN12 cells revealed that p130Cas, Dek, Src and talin were required for invasion through Matrigel. Disruption of talin or p130Cas by RNA interference increased resistance to cisplatin, whereas targeting Dek, Src or zyxin reduced HN12 resistance to cisplatin. Analysis of the spreading of HN12 cells on collagen I and laminin I revealed that a decrease in p130Cas or talin expression inhibited spreading on both matrices. Interestingly, a reduction in zyxin expression enhanced spreading on laminin I and inhibited spreading on collagen I. Reduction of Dek, Src, talin or zyxin expression reduced HN12 proliferation by 30%. Proliferation was not affected by a reduction in p130Cas expression. We conclude that p130Cas, Src and talin function in both oral carcinoma invasion and resistance to cisplatin.

  5. Inhibition of hypoxia inducible factor-1alpha by dihydroxyphenylethanol, a product from olive oil, blocks microsomal prostaglandin-E synthase-1/vascular endothelial growth factor expression and reduces tumor angiogenesis.

    Science.gov (United States)

    Terzuoli, Erika; Donnini, Sandra; Giachetti, Antonio; Iñiguez, Miguel A; Fresno, Manuel; Melillo, Giovanni; Ziche, Marina

    2010-08-15

    2-(3,4-dihydroxyphenil)-ethanol (DPE), a polyphenol present in olive oil, has been found to attenuate the growth of colon cancer cells, an effect presumably related to its anti-inflammatory activity. To further explore the effects of DPE on angiogenesis and tumor growth we investigated the in vivo efficacy of DPE in a HT-29 xenograft model and in vitro activities in colon cancer cells exposed to interleukin-1beta (IL-1beta) and prostaglandin E-2 (PGE-2). DPE (10 mg/kg/day for 14 days) inhibited tumor growth, reducing vessel lumina and blood perfusion to tumor, and diminished expression of hypoxia inducible factor-1alpha (HIF-1alpha), vascular endothelial growth factor (VEGF), and microsomal prostaglandin-E synthase-1 (mPGEs-1). In vitro, DPE (100 mumol/L) neither affected cell proliferation nor induced apoptosis in HT-29 and WiDr cells. DPE prevented the IL-1beta-mediated increase of mPGEs-1 expression and PGE-2 generation, as it did the silencing of HIF-1alpha. Moreover, DPE blocked mPGEs-1-dependent expression of VEGF and inhibited endothelial sprouting induced by tumor cells in a coculture system. PGE-2 triggers a feed-forward loop involving HIF-1alpha, which impinges on mPGEs-1 and VEGF expression, events prevented by DPE via extracellular signal-related kinase 1/2. The reduction of PGE-2 and VEGF levels, caused by DPE, was invariably associated with a marked decrease in HIF-1alpha expression and activity, independent of proteasome activity, indicating that the DPE effects on tumor growth and angiogenesis are dependent on the inhibition of HIF-1alpha translation. We show that the in vivo DPE antitumor effect is associated with anti-inflammatory and antiangiogenic activities resulting from the downregulation of the HIF-1alpha/mPGEs-1/VEGF axis.

  6. Coactivator PGC-1α regulates the fasting inducible xenobiotic-metabolizing enzyme CYP2A5 in mouse primary hepatocytes

    International Nuclear Information System (INIS)

    Arpiainen, Satu; Jaervenpaeae, Sanna-Mari; Manninen, Aki; Viitala, Pirkko; Lang, Matti A.; Pelkonen, Olavi; Hakkola, Jukka

    2008-01-01

    The nutritional state of organisms and energy balance related diseases such as diabetes regulate the metabolism of xenobiotics such as drugs, toxins and carcinogens. However, the mechanisms behind this regulation are mostly unknown. The xenobiotic-metabolizing cytochrome P450 (CYP) 2A5 enzyme has been shown to be induced by fasting and by glucagon and cyclic AMP (cAMP), which mediate numerous fasting responses. Peroxisome proliferator-activated receptor γ coactivator (PGC)-1α triggers many of the important hepatic fasting effects in response to elevated cAMP levels. In the present study, we were able to show that cAMP causes a coordinated induction of PGC-1α and CYP2A5 mRNAs in murine primary hepatocytes. Furthermore, the elevation of the PGC-1α expression level by adenovirus mediated gene transfer increased CYP2A5 transcription. Co-transfection of Cyp2a5 5' promoter constructs with the PGC-1α expression vector demonstrated that PGC-1α is able to activate Cyp2a5 transcription through the hepatocyte nuclear factor (HNF)-4α response element in the proximal promoter of the Cyp2a5 gene. Chromatin immunoprecipitation assays showed that PGC-1α binds, together with HNF-4α, to the same region at the Cyp2a5 proximal promoter. In conclusion, PGC-1α mediates the expression of CYP2A5 induced by cAMP in mouse hepatocytes through coactivation of transcription factor HNF-4α. This strongly suggests that PGC-1α is the major factor mediating the fasting response of CYP2A5

  7. Activation of a PGC-1-related Coactivator (PRC)-dependent Inflammatory Stress Program Linked to Apoptosis and Premature Senescence*

    Science.gov (United States)

    Gleyzer, Natalie; Scarpulla, Richard C.

    2013-01-01

    PGC-1-related coactivator (PRC), a growth-regulated member of the PGC-1 coactivator family, contributes to the expression of the mitochondrial respiratory apparatus. PRC also orchestrates a robust response to metabolic stress by promoting the expression of multiple genes specifying inflammation, proliferation, and metabolic reprogramming. Here, we demonstrate that this PRC-dependent stress program is activated during apoptosis and senescence, two major protective mechanisms against cellular dysfunction. Both PRC and its targets (IL1α, SPRR2D, and SPRR2F) were rapidly induced by menadione, an agent that promotes apoptosis through the generation of intracellular oxidants. Menadione-induced apoptosis and the PRC stress program were blocked by the antioxidant N-acetylcysteine. The PRC stress response was also activated by the topoisomerase I inhibitor 7-ethyl-10-hydroxycamptothecin (SN-38), an inducer of premature senescence in tumor cells. Cells treated with SN-38 displayed morphological characteristics of senescence and express senescence-associated β-galactosidase activity. In contrast to menadione, the SN-38 induction of the PRC program occurred over an extended time course and was antioxidant-insensitive. The potential adaptive function of the PRC stress response was investigated by treating cells with meclizine, a drug that promotes glycolytic energy metabolism and has been linked to cardio- and neuroprotection against ischemia-reperfusion injury. Meclizine increased lactate production and was a potent inducer of the PRC stress program, suggesting that PRC may contribute to the protective effects of meclizine. Finally, c-MYC and PRC were coordinately induced under all conditions tested, implicating c-MYC in the biological response to metabolic stress. The results suggest a general role for PRC in the adaptive response to cellular dysfunction. PMID:23364789

  8. GR and ER co-activation alters the expression of differentiation genes and associates with improved ER+ breast cancer outcome

    Science.gov (United States)

    West, Diana C.; Pan, Deng; Tonsing-Carter, Eva Y.; Hernandez, Kyle M.; Pierce, Charles F.; Styke, Sarah C.; Bowie, Kathleen R.; Garcia, Tzintzuni I.; Kocherginsky, Masha; Conzen, Suzanne D.

    2016-01-01

    In estrogen receptor (ER)-negative breast cancer (BC), high tumor glucocorticoid receptor (GR) expression has been associated with a relatively poor outcome. In contrast, using a meta-analysis of several genomic datasets, here we find that tumor GR mRNA expression is associated with improved ER+ relapse-free survival (RFS) (independently of progesterone receptor (PR) expression). To understand the mechanism by which GR expression is associated with a better ER+ BC outcome, the global effect of GR-mediated transcriptional activation in ER+ BC cells was studied. Analysis of GR chromatin immunoprecipitation followed by high-throughput sequencing (ChIP-seq) in ER+/GR+ MCF-7 cells revealed that upon co-activation of GR and ER, GR chromatin association became enriched at proximal promoter regions. Furthermore, following ER activation, increased GR chromatin association was observed at ER, FOXO, and AP1 response elements. In addition, ER associated with GR response elements, suggesting that ER and GR interact in a complex. Co-activation of GR and ER resulted in increased expression (relative to ER activation alone) of transcripts that encode proteins promoting cellular differentiation (e.g. KDM4B, VDR) and inhibiting the Wnt-signaling pathway (IGFBP4). Finally, expression of these individual pro-differentiation genes was associated with significantly improved RFS in ER+ BC patients. Together, these data suggest that the co-expression and subsequent activity of tumor cell GR and ER contribute to the less aggressive natural history of early-stage BC by coordinating the altered expression of genes favoring differentiation. Implications The interaction between estrogen and glucocorticoid receptor activity highlights the importance of context-dependent nuclear receptor function in cancer. PMID:27141101

  9. Effects of 1alpha-hydroxycholecalciferol on growth performance, parameters of tibia and plasma, meat quality, and type IIb sodium phosphate cotransporter gene expression of one- to twenty-one-day-old broilers.

    Science.gov (United States)

    Han, J C; Yang, X D; Zhang, T; Li, H; Li, W L; Zhang, Z Y; Yao, J H

    2009-02-01

    This experiment was conducted to investigate the effects of 1alpha-hydroxycholecalciferol (1alpha-OH D3) on the growth performance, tibia and plasma parameters, nutrient utilization, meat quality of the breast and thigh, and type IIb sodium phosphate cotranspoter gene expression of broilers. A total of 96 males of 1-d-old Arbor Acres broilers were randomly assigned to 8 cages of 12 birds each. Two dietary treatments were applied to 4 cages each. Diet 1 was prepared as the basal diet (nonphytate phosphorus, 0.21%), whereas diet 2 was the basal diet supplemented with 5 microg/kg of 1alpha-OH D3. Results showed that supplementation of the basal diet with 1alpha-OH D3 increased growth performance, tibia ash and strength, plasma inorganic phosphate concentration, utilization of total phosphorus and nonphytate phosphorus, lightness and yellowness of the breast and thigh meat, and intestinal type IIb sodium phosphate cotranspoter mRNA expression, whereas it decreased the shear force and water-holding capacity of the thigh meat. These data suggest that the addition of 1alpha-OH D3 might improve growth performance, tibia development, and meat quality in 1- to 21-d-old broilers by increasing the absorption and retention of phosphorus.

  10. Evidence of a bigenomic regulation of mitochondrial gene expression by thyroid hormone during rat brain development

    Energy Technology Data Exchange (ETDEWEB)

    Sinha, Rohit Anthony; Pathak, Amrita; Mohan, Vishwa; Babu, Satish; Pal, Amit; Khare, Drirh [Department of Endocrinology, Sanjay Gandhi Postgraduate Institute of Medical Sciences, Lucknow 226014 (India); Godbole, Madan M., E-mail: madangodbole@yahoo.co.in [Department of Endocrinology, Sanjay Gandhi Postgraduate Institute of Medical Sciences, Lucknow 226014 (India)

    2010-07-02

    Hypothyroidism during early mammalian brain development is associated with decreased expression of various mitochondrial encoded genes along with evidence for mitochondrial dysfunction. However, in-spite of the similarities between neurological disorders caused by perinatal hypothyroidism and those caused by various genetic mitochondrial defects we still do not know as to how thyroid hormone (TH) regulates mitochondrial transcription during development and whether this regulation by TH is nuclear mediated or through mitochondrial TH receptors? We here in rat cerebellum show that hypothyroidism causes reduction in expression of nuclear encoded genes controlling mitochondrial biogenesis like PGC-1{alpha}, NRF-1{alpha} and Tfam. Also, we for the first time demonstrate a mitochondrial localization of thyroid hormone receptor (mTR) isoform in developing brain capable of binding a TH response element (DR2) present in D-loop region of mitochondrial DNA. These results thus indicate an integrated nuclear-mitochondrial cross talk in regulation of mitochondrial transcription by TH during brain development.

  11. Long-term effects of intravenous 1 alpha (OH)D3 combined with CaCO3 and low-calcium dialysis on secondary hyperparathyroidism and biochemical bone markers in patients on chronic hemodialysis

    DEFF Research Database (Denmark)

    Brandi, L; Daugaard, H; Nielsen, P K

    1996-01-01

    doses of CaCO3 and to reduce the doses of an aluminium-containing oral phosphate binder. A decrease in p-Ca2+ during dialysis was induced, and special care had to focus on the compliance to CaCO3, in order not to aggravate the secondary hyperparathyroidism. (2) The combination of 'low......The effects of intravenous administration of 1 alpha-hydroxycholecalciferol [1 alpha (OH)D3] in combination with CaCO3 and 'low-calcium dialysis' (1.25 mmol/l) on plasma (p) parathyroid hormone (PTH) and biochemical bone markers (osteocalcin, alkaline phosphatase, procollagen type 1 c......-terminal extension peptide) were examined in 54 patients on chronic hemodialysis with either normal or elevated PTH. Increasing doses of 1 alpha (OH)D3 were administered intravenously under careful control of p-Ca2+ and inorganic phosphate. Blood samples were obtained 1 week before the start of treatment...

  12. Malaria-specific metabolite hemozoin mediates the release of several potent endogenous pyrogens (TNF, MIP-1 alpha, and MIP-1 beta) in vitro, and altered thermoregulation in vivo.

    Science.gov (United States)

    Sherry, B A; Alava, G; Tracey, K J; Martiney, J; Cerami, A; Slater, A F

    1995-01-01

    A characteristic feature of malaria infection is the occurrence of periodic bouts of fever. Experimental and clinical studies have strongly implicated inflammatory cytokines, like tumour necrosis factor (TNF), in the induction of these intermittent fevers [Clark et al., Infect Immunol 32:1058-1066, 1981; Clark et al., Am J Pathol 129:192-199, 1987; Karunaweera et al., Proc Natl Acad Sci USA 89:3200-3203, 1992], but the malaria-specific metabolite(s) which induce the production of such endogenous pyrogens have not yet been fully characterized. It is well known that during the course of malaria infection, a unique schizont component, alternatively referred to as "malaria pigment" or hemozoin, is released along with merozoites as the host erythrocyte bursts [Urquhart, Clin Infect Dis 19:117-131, 1994]. We have recently determined that the core structure of hemozoin comprises a novel insoluble polymer of heme units linked by iron-carboxylate bonds [Slater et al., Proc Natl Acad Sci USA 88:325-329, 1991; Slater et al., Nature 355:167-169, 1992]. We now report that purified native, as well as chemically synthesized, hemozoin crystals potently induce the release of several pyrogenic cytokines, including TNF, MIP-1 alpha, and MIP-1 beta, from murine macrophages and human peripheral blood monocytes in vitro. Also, intravenous administration of chemically synthesized preparations of hemozoin to anaesthetized rats results in a marked drop in body temperature. A similar drop in body temperature is observed following the intravenous injection of other well-characterized pyrogenic cytokines (e.g., TNF) which are known to induce a fever response in awake animals, and is thought to reflect the inability of rats to appropriately regulate their body temperature while anaesthetized. As a consequence of its ability to induce pyrogenic cytokines in vitro, and thermal dysregulation in vivo, we propose that this unique parasite metabolite is an important pyrogen released by malaria

  13. Three-Dimensional Conformal Radiotherapy in Prostate Cancer Patients: Rise in Interleukin 6 (IL-6) but not IL-2, IL-4, IL-5, Tumor Necrosis Factor-{alpha}, MIP-1-{alpha}, and LIF Levels

    Energy Technology Data Exchange (ETDEWEB)

    Oliveira Lopes, Carlos [Universidade do Vale do Paraiba, Centro de Oncologia Radioterapica do Vale do Paraiba, Universidade do Vale do Paraiba Instituto de Pesquisa e Desenvolvimento, Universidade do Vale do Paraiba, Sao Jose dos Campos, Sao Paulo (Brazil); Callera, Fernando, E-mail: fcallera@gmail.com [Centro de Hematologia Onco-hematologia e Transplantes de Medula Ossea do Vale do Paraiba, Sao Paulo (Brazil)

    2012-03-15

    Purpose: To investigate the effect of radiotherapy (RT) on serum levels of interleukin-2 (IL-2), IL-4, IL-5, IL-6, tumor necrosis factor alpha (TNF-{alpha}), macrophage inflammatory protein-1-alpha (MIP-1-{alpha}) and leukemia inhibitory factor (LIF) in patients with prostate cancer. Methods and Materials: Forty eight patients with prostate cancer received three-dimensional conformal blocking radiation therapy with a linear accelerator. IL-2, IL-4, IL-5, IL-6, TNF-{alpha}, MIP-1-{alpha}, and LIF levels were measured by the related immunoassay kit 1 day before the beginning of RT and during RT at days 15 and 30. Results: The mean IL-2 values were elevated before and during the RT in contrast with those of IL-4, IL-5, IL-6, TNF-{alpha}, MIP-1-{alpha}, and LIF, which were within the normal range under the same conditions. Regarding markers IL-2, IL-4, IL-5, TNF-{alpha}, MIP-1-{alpha}, and LIF, comparisons among the three groups (before treatment and 15 and 30 days during RT) did not show significant differences. Although values were within the normal range, there was a significant rise in IL-6 levels at day 15 of RT (p = 0.0049) and a decline at day 30 to levels that were similar to those observed before RT. Conclusions: IL-6 appeared to peak after 15 days of RT before returning to pre-RT levels. In contrast, IL-2, IL-4, IL-5, TNF-{alpha}, MIP-1-{alpha}, and LIF levels were not sensitive to irradiation. The increased levels of IL-6 following RT without the concurrent elevation of other cytokines involved in the acute phase reaction did not suggest a classical inflammatory response to radiation exposure. Further studies should be designed to elucidate the role of IL-6 levels in patients with prostate cancer treated with RT.

  14. Analysis of the local kinetics and localization of interleukin-1 alpha, tumour necrosis factor-alpha and transforming growth factor-beta, during the course of experimental pulmonary tuberculosis.

    Science.gov (United States)

    Hernandez-Pando, R; Orozco, H; Arriaga, K; Sampieri, A; Larriva-Sahd, J; Madrid-Marina, V

    1997-01-01

    A mouse model of pulmonary tuberculosis induced by the intratracheal instillation of live and virulent mycobacteria strain H37-Rv was used to examine the relationship of the histopathological findings with the local kinetics production and cellular distribution of tumour necrosis factor-alpha (TNF-alpha), interleukin-1 alpha (IL-1 alpha) and transforming growth factor-beta (TGF-beta). The histopathological and immunological studies showed two phases of the disease: acute or early and chronic or advanced. The acute phase was characterized by inflammatory infiltrate in the alveolar-capillary interstitium, blood vessels and bronchial wall with formation of granulomas. During this acute phase, which lasted from 1 to 28 days, high percentages of TNF-alpha and IL-1 alpha immunostained activated macrophages were observed principally in the interstium-intralveolar inflammatory infiltrate and in granulomas. Electron microscopy studies of these cells, showed extensive rough endoplasmic reticulum, numerous lysosomes and occasional mycobacteria. Double labelling with colloid gold showed that TNF-alpha and IL-1 alpha were present in the same cells, but were confined to separate vacuoles near the Golgi area, and mixed in larger vacuoles near to cell membrane. The concentration of TNF-alpha and IL-1 alpha as well as their respective mRNAs were elevated in the early phase, particularly at day 3 when the bacillary count decreased. A second peak was seen at days 14 and 21-28 when granulomas appeared and evolved to full maturation. In contrast, TGF-beta production and numbers of immunoreactive cells were low in comparison with the advanced phase of the disease. The chronic phase was characterized by histopathological changes indicative of more severity (i.e. pneumonia, focal necrosis and extensive interstitial fibrosis) with a decrease in the TNF-alpha and IL-1 alpha production that coincided with the highest level of TGF-beta. The bacillary counts were highest as the macrophages

  15. Corepressive function of nuclear receptor coactivator 2 in androgen receptor of prostate cancer cells treated with antiandrogen

    International Nuclear Information System (INIS)

    Takeda, Keisuke; Hara, Noboru; Nishiyama, Tsutomu; Tasaki, Masayuki; Ishizaki, Fumio; Tomita, Yoshihiko

    2016-01-01

    Recruitment of cofactors in the interaction of the androgen receptor (AR) and AR ligands plays a critical role in determining androgenic/antiandrogenic effects of the AR ligand on signaling, but the functions of key cofactors, including nuclear receptor coactivator (NCOA), remain poorly understood in prostate cancer cells treated with AR ligands. We examined prostate cancer cell lines LNCaP and VCaP expressing mutated and wild-type ARs, respectively, to clarify the significance of NCOAs in the effect of antiandrogens. Hydroxyflutamide showed antagonistic activity against VCaP and an agonistic effect on LNCaP. Bicalutamide served as an antagonist for both. We analyzed mRNA transcription and protein expression of NCOAs in these cells pretreated with dihydrotestosterone and thereafter treated with the mentioned antiandrogens. Transcriptional silencing of candidate NCOAs and AR was performed using small interfering RNA (siRNA). Cell proliferation was evaluated with MTT assay. LNCaP treated with bicalutamide showed an about four-fold increase in the expression of NCOA2 mRNA compared to those pretreated with dihydrotestosterone alone (P <0.01). In VCaP pretreated with dihydrotestosterone, transcriptions of NCOA2 and NCOA7 were slightly increased with bicalutamide (1.96- and 2.42-fold, respectively) and hydroxyflutamide (1.33-fold in both). With Western blotting, the expression of NCOA2 protein also increased in LNCaP cells treated with bicalutamide compared with that in control cells pretreated with dihydrotestosterone alone. Following silencing with siRNA for NCOA2, PSA levels in media with LNCaP receiving bicalutamide were elevated compared with those in non-silencing controls (101.6 ± 4.2 vs. 87.8 ± 1.4 ng/mL, respectively, P =0.0495). In LNCaP cells treated with dihydrotestosterone and bicalutamide, NCOA2-silencing was associated with a higher proliferation activity compared with non-silencing control and AR-silencing. NCOA2, which has been thought to be recruited

  16. Steroid receptor coactivators, HER-2 and HER-3 expression is stimulated by tamoxifen treatment in DMBA-induced breast cancer

    International Nuclear Information System (INIS)

    Moi, Line L Haugan; Flågeng, Marianne Hauglid; Gjerde, Jennifer; Madsen, Andre; Røst, Therese Halvorsen; Gudbrandsen, Oddrun Anita; Lien, Ernst A; Mellgren, Gunnar

    2012-01-01

    Steroid receptor coactivators (SRCs) may modulate estrogen receptor (ER) activity and the response to endocrine treatment in breast cancer, in part through interaction with growth factor receptor signaling pathways. In the present study the effects of tamoxifen treatment on the expression of SRCs and human epidermal growth factor receptors (HERs) were examined in an animal model of ER positive breast cancer. Sprague-Dawley rats with DMBA-induced breast cancer were randomized to 14 days of oral tamoxifen 40 mg/kg bodyweight/day or vehicle only (controls). Tumors were measured throughout the study period. Blood samples and tumor tissue were collected at sacrifice and tamoxifen and its main metabolites were quantified using LC-MS/MS. The gene expression in tumor of SRC-1, SRC-2/transcription intermediary factor-2 (TIF-2), SRC-3/amplified in breast cancer 1 (AIB1), ER, HER-1, -2, -3 and HER-4, as well as the transcription factor Ets-2, was measured by real-time RT-PCR. Protein levels were further assessed by Western blotting. Tamoxifen and its main metabolites were detected at high concentrations in serum and accumulated in tumor tissue in up to tenfolds the concentration in serum. Mean tumor volume/rat decreased in the tamoxifen treated group, but continued to increase in controls. The mRNA expression levels of SRC-1 (P = 0.035), SRC-2/TIF-2 (P = 0.002), HER-2 (P = 0.035) and HER-3 (P = 0.006) were significantly higher in tamoxifen treated tumors compared to controls, and the results were confirmed at the protein level using Western blotting. SRC-3/AIB1 protein was also higher in tamoxifen treated tumors. SRC-1 and SRC-2/TIF-2 mRNA levels were positively correlated with each other and with HER-2 (P ≤ 0.001), and the HER-2 mRNA expression correlated with the levels of the other three HER family members (P < 0.05). Furthermore, SRC-3/AIB1 and HER-4 were positively correlated with each other and Ets-2 (P < 0.001). The expression of SRCs and HER-2 and -3 is stimulated

  17. Down-regulation of hypoxia-inducible factor-1 alpha and vascular endothelial growth factor by HEXIM1 attenuates myocardial angiogenesis in hypoxic mice.

    Science.gov (United States)

    Yoshikawa, Noritada; Shimizu, Noriaki; Ojima, Hidenori; Kobayashi, Hiroshi; Hosono, Osamu; Tanaka, Hirotoshi

    2014-10-24

    Pulmonary hypertension (PH) sustains elevation of pulmonary vascular resistance and ultimately leads to right ventricular (RV) hypertrophy and failure and death. Recently, proangiogenic factors hypoxia-inducible factor-1 alpha (HIF-1α) and vascular endothelial growth factor (VEGF) have been known to promote left ventricular myocardial angiogenesis and lead to cardiac hypertrophy, and this would be involved in RV hypertrophy of PH patients. Previously, we revealed that overexpression of HEXIM1 prevents endothelin-1-induced cardiomyocyte hypertrophy and hypertrophic genes expression, and that cardiomyocyte-specific HEXIM1 transgenic mice ameliorates RV hypertrophy in hypoxia-induced PH model. Given these results, here we analyzed the effect of HEXIM1 on the expression of HIF-1α and VEGF and on myocardial angiogenesis of RV in PH. We revealed that overexpression of HEXIM1 prevented hypoxia-induced expression of HIF-1α protein and its target genes including VEGF in the cultured cardiac myocytes and fibroblasts, and that cardiomyocyte-specific HEXIM1 transgenic mice repressed RV myocardial angiogenesis in hypoxia-induced PH model. Thus, we conclude that HEXIM1 could prevent RV hypertrophy, at least in part, via suppression of myocardial angiogenesis through down-regulation of HIF-1α and VEGF in the myocardium under hypoxic condition. Copyright © 2014 Elsevier Inc. All rights reserved.

  18. Hypoxia-inducible factor 1-alpha up-regulates the expression of phospholipase D2 in colon cancer cells under hypoxic conditions.

    Science.gov (United States)

    Liu, Maoxi; Du, Kunli; Fu, Zhongxue; Zhang, Shouru; Wu, Xingye

    2015-01-01

    Hypoxia is a common characteristic of solid tumors. Recent studies confirmed that phospholipase D2 (PLD2) plays significant roles in cancer progression. In this study, correlation between the expression of PLD2 and the change in the protein level of hypoxia-inducible factor 1-alpha (HIF1-α) was studied. Thirty human colon cancer tissues were examined for the expression of HIF1-α and PLD2 protein, and mRNA levels. SW480 and SW620 cells were exposed to normoxia (20 %) or hypoxia (Hypoxic stress induced PLD2 mRNA and protein expression in SW480 and SW620 cells. Cells transfected with HIF1-α siRNA showed attenuation of hypoxia stress-induced PLD2 expression. In vivo growth decreased in response to HIF1-α and PLD2 inhibition. These results suggest that PLD2 expression in colon cancer cells is up-regulated via HIF1-α in response to hypoxic stress and underscores the crucial role of HIF1-α-induced PLD2 in tumor growth.

  19. Interleukins 1alpha and 1beta secreted by some melanoma cell lines strongly reduce expression of MITF-M and melanocyte differentiation antigens.

    Science.gov (United States)

    Kholmanskikh, Olga; van Baren, Nicolas; Brasseur, Francis; Ottaviani, Sabrina; Vanacker, Julie; Arts, Nathalie; van der Bruggen, Pierre; Coulie, Pierre; De Plaen, Etienne

    2010-10-01

    We report that melanoma cell lines expressing the interleukin-1 receptor exhibit 4- to 10-fold lower levels of mRNA of microphthalmia-associated transcription factor (MITF-M) when treated with interleukin-1beta. This effect is NF-kappaB and JNK-dependent. MITF-M regulates the expression of melanocyte differentiation genes such as MLANA, tyrosinase and gp100, which encode antigens recognized on melanoma cells by autologous cytolytic T lymphocytes. Accordingly, treating some melanoma cells with IL-1beta reduced by 40-100% their ability to activate such antimelanoma cytolytic T lymphocytes. Finally, we observed large amounts of biologically active IL-1alpha or IL-1beta secreted by two melanoma cell lines that did not express MITF-M, suggesting an autocrine MITF-M downregulation. We estimate that approximately 13% of melanoma cell lines are MITF-M-negative and secrete IL-1 cytokines. These results indicate that the repression of melanocyte-differentiation genes by IL-1 produced by stromal cells or by tumor cells themselves may represent an additional mechanism of melanoma immune escape.

  20. Endothelial monocyte activating polypeptide-II modulates endothelial cell responses by degrading hypoxia-inducible factor-1alpha through interaction with PSMA7, a component of the proteasome

    International Nuclear Information System (INIS)

    Tandle, Anita T.; Calvani, Maura; Uranchimeg, Badarch; Zahavi, David; Melillo, Giovanni; Libutti, Steven K.

    2009-01-01

    The majority of human tumors are angiogenesis dependent. Understanding the specific mechanisms that contribute to angiogenesis may offer the best approach to develop therapies to inhibit angiogenesis in cancer. Endothelial monocyte activating polypeptide-II (EMAP-II) is an anti-angiogenic cytokine with potent effects on endothelial cells (ECs). It inhibits EC proliferation and cord formation, and it suppresses primary and metastatic tumor growth in-vivo. However, very little is known about the molecular mechanisms behind the anti-angiogenic activity of EMAP-II. In the present study, we explored the molecular mechanism behind the anti-angiogenic activity exerted by this protein on ECs. Our results demonstrate that EMAP-II binds to the cell surface α5β1 integrin receptor. The cell surface binding of EMAP-II results in its internalization into the cytoplasmic compartment where it interacts with its cytoplasmic partner PSMA7, a component of the proteasome degradation pathway. This interaction increases hypoxia-inducible factor 1-alpha (HIF-1α) degradation under hypoxic conditions. The degradation results in the inhibition of HIF-1α mediated transcriptional activity as well as HIF-1α mediated angiogenic sprouting of ECs. HIF-1α plays a critical role in angiogenesis by activating a variety of angiogenic growth factors. Our results suggest that one of the major anti-angiogenic functions of EMAP-II is exerted through its inhibition of the HIF-1α activities.

  1. EXERCISES THAT FACILITATE OPTIMAL HAMSTRING AND QUADRICEPS CO-ACTIVATION TO HELP DECREASE ACL INJURY RISK IN HEALTHY FEMALES: A SYSTEMATIC REVIEW OF THE LITERATURE.

    Science.gov (United States)

    Dedinsky, Rachel; Baker, Lindsey; Imbus, Samuel; Bowman, Melissa

    2017-01-01

    Background Anterior cruciate ligament (ACL) injury is common among females due to many anatomic, hormonal, and neuromuscular risk factors. One modifiable risk factor that places females at increased risk of ACL injury is a poor hamstrings: quadriceps (H:Q) co-activation ratio, which should be 0.6 or greater in order to decrease the stress placed on the ACL. Exercises that produce more quadriceps dominant muscle activation can add to the tension placed upon the ACL, potentially increasing the risk of ACL injury. Hypothesis/Purpose The purpose of this systematic review was to compare quadriceps and hamstring muscle activation during common closed kinetic chain therapeutic exercises in healthy female knees to determine what exercises are able to produce adequate H:Q co-activation ratios. Study Design Systematic Review Methods Multiple online databases were systematically searched and screened for inclusion. Eight articles were identified for inclusion. Data on mean electromyography (EMG) activation of both quadriceps and hamstring muscles, % maximal voluntary isometric contraction (MVIC), and H:Q co-activation ratios were extracted from the studies. Quality assessment was performed on all included studies. Results Exercises analyzed in the studies included variations of the double leg squat, variations of the single leg squat, lateral step-up, Fitter, Stairmaster® (Core Health and Fitness, Vancouver, WA), and slide board. All exercises, except the squat machine with posterior support at the level of the scapula and feet placed 50 cm in front of the hips, produced higher quadriceps muscle activation compared to hamstring muscle activation. Conclusion Overall, two leg squats demonstrate poor H:Q co-activation ratios. Single leg exercises, when performed between 30 and 90 degrees of knee flexion, produce adequate H:Q ratios, thereby potentially reducing the risk of tensile stress on the ACL and ACL injury. Level of Evidence 2a- Systematic Review of Cohort Studies PMID

  2. Luminescence properties of Ce3+ and Tb3+ co-activated ZnAl2O4 phosphor

    International Nuclear Information System (INIS)

    Tshabalala, K.G.; Cho, S.-H.; Park, J.-K.; Pitale, Shreyas S.; Nagpure, I.M.; Kroon, R.E.; Swart, H.C.; Ntwaeaborwa, O.M.

    2012-01-01

    In this study, a solution combustion method was used to prepare green emitting Ce 3+ –Tb 3+ co-activated ZnAl 2 O 4 phosphor. The samples were annealed at 700 °C in air or hydrogen atmosphere to improve their crystallinity and optical properties. X-ray diffraction study confirmed that both as-prepared and post-preparation annealed samples crystallized in the well known cubic spinel structure of ZnAl 2 O 4 . An agglomeration of irregular platelet-like particles whose surfaces were encrusted with smaller spheroidal particles was confirmed by scanning electron microscopy (SEM). The fluorescence data collected from the annealed samples with different concentrations of Ce 3+ and Tb 3+ show the enhanced green emission at 543 nm associated with 5 D 4 → 7 F 5 transitions of Tb 3+ . The enhancement was attributed to energy transfer from Ce 3+ to Tb 3+ . Possible mechanism of energy transfer via a down conversion process is discussed. Furthermore, cathodoluminescence (CL) intensity degradation of this phosphor was also investigated and the degradation data suggest that the material was chemically stable and the CL intensity was also stable after 10 h of irradiation by a beam of high energy electrons.

  3. A muscle-specific knockout implicates nuclear receptor coactivator MED1 in the regulation of glucose and energy metabolism.

    Science.gov (United States)

    Chen, Wei; Zhang, Xiaoting; Birsoy, Kivanc; Roeder, Robert G

    2010-06-01

    As conventional transcriptional factors that are activated in diverse signaling pathways, nuclear receptors play important roles in many physiological processes that include energy homeostasis. The MED1 subunit of the Mediator coactivator complex plays a broad role in nuclear receptor-mediated transcription by anchoring the Mediator complex to diverse promoter-bound nuclear receptors. Given the significant role of skeletal muscle, in part through the action of nuclear receptors, in glucose and fatty acid metabolism, we generated skeletal muscle-specific Med1 knockout mice. Importantly, these mice show enhanced insulin sensitivity and improved glucose tolerance as well as resistance to high-fat diet-induced obesity. Furthermore, the white muscle of these mice exhibits increased mitochondrial density and expression of genes specific to type I and type IIA fibers, indicating a fast-to-slow fiber switch, as well as markedly increased expression of the brown adipose tissue-specific UCP-1 and Cidea genes that are involved in respiratory uncoupling. These dramatic results implicate MED1 as a powerful suppressor in skeletal muscle of genetic programs implicated in energy expenditure and raise the significant possibility of therapeutical approaches for metabolic syndromes and muscle diseases through modulation of MED1-nuclear receptor interactions.

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

    Directory of Open Access Journals (Sweden)

    Zhi Chen

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

  5. Bacteriophage T5 encodes a homolog of the eukaryotic transcription coactivator PC4 implicated in recombination-dependent DNA replication.

    Science.gov (United States)

    Steigemann, Birthe; Schulz, Annina; Werten, Sebastiaan

    2013-11-15

    The RNA polymerase II cofactor PC4 globally regulates transcription of protein-encoding genes through interactions with unwinding DNA, the basal transcription machinery and transcription activators. Here, we report the surprising identification of PC4 homologs in all sequenced representatives of the T5 family of bacteriophages, as well as in an archaeon and seven phyla of eubacteria. We have solved the crystal structure of the full-length T5 protein at 1.9Å, revealing a striking resemblance to the characteristic single-stranded DNA (ssDNA)-binding core domain of PC4. Intriguing novel structural features include a potential regulatory region at the N-terminus and a C-terminal extension of the homodimerisation interface. The genome organisation of T5-related bacteriophages points at involvement of the PC4 homolog in recombination-dependent DNA replication, strongly suggesting that the protein corresponds to the hitherto elusive replicative ssDNA-binding protein of the T5 family. Our findings imply that PC4-like factors intervene in multiple unwinding-related processes by acting as versatile modifiers of nucleic acid conformation and raise the possibility that the eukaryotic transcription coactivator derives from ancestral DNA replication, recombination and repair factors. © 2013.

  6. Serum concentrations of interleukin (IL-)1alpha, 1beta, 6 and tumor necrosis factor (TNF-) alpha in patients with thyroid eye disease (TED).

    Science.gov (United States)

    Laban-Guceva, Nevenka; Bogoev, Milko; Antova, Magdalena

    2007-01-01

    Serum proinflamatory cytokines were found to be altered in Graves disease (GD) and in TED. Serum values of IL1alpha, IL-1beta, IL-6, TNF-alpha were assessed in 22 patients with TED before and after treatment (aged 46.82 +/- 12.47, M:F=16:6). Free thyroxin was high, TSH low, thyroid ultrasound showed diffuse thyroid enlargement, treatment with antithyroid drugs propylthyouracil (PTU) or methymasol (MMI) resulted in clinical and hormonal remission. Several months after the initiation of the signs of hyperthyroidism, a progression in the ophthalmopathy was observed (Hertel up to 25 mm: normal 15-17 mm) while patients were clinically and hormonally euthyroid. Blood was collected in euthyroid state (with TED signs present, before corticosteroid therapy (CS) treatment) and after 3 months of treatment (patients without TED and without TED treatment). CS resulted in response of 8/22 patients. Ophthalmic irradiation (01) given with CS therapy, resulted in a response in twelve patients (12/12). Lack of response to CS treatment, with rapid increase in proptosis, and loss of visual acuity prompted ophthalmic decompression (OD) in two patients. Both recovered visual acuity, while proptosis fell under 25 mm Hertel. The control group had 29 persons (aged 51.86 +/-10.52, M:F = 16:13). A significant difference was found in the serum levels of IL-1alpha between the groups of controls (0.74+/-0.55 pg/ml) and patients before treatment (1.85 +/- 1.85 pg/ml; p TED treatment its concentration raised to 2.07 +/- 1.82 pg/ml (higher than the pretreatment; NS). For patients with low Clinical Activity Score (CAS) scores (1-5) there was no change in IL-6 concentrations before (1.03+/-o.64 pg/ml) and after treatment (1.07 +/- 0.63 pg/ml). Patients with higher CAS scores (6-10) had a change in IL-6 levels (from 1.32+/-1.00 to 2.67 +/- 4.84; p > 0.05). In addition, patients with pathological VEP had no changes in IL-6 (from 0.93 +/- 0.53 to 0.97 +/- 0.32 pg/ml), while patients with normal VEP had

  7. Inhibition of protein kinase C delta attenuates allergic airway inflammation through suppression of PI3K/Akt/mTOR/HIF-1 alpha/VEGF pathway.

    Directory of Open Access Journals (Sweden)

    Yun Ho Choi

    Full Text Available Vascular endothelial growth factor (VEGF is supposed to contribute to the pathogenesis of allergic airway disease. VEGF expression is regulated by a variety of stimuli such as nitric oxide, growth factors, and hypoxia-inducible factor-1 alpha (HIF-1α. Recently, inhibition of the mammalian target of rapamycin (mTOR has been shown to alleviate cardinal asthmatic features, including airway hyperresponsiveness, eosinophilic inflammation, and increased vascular permeability in asthma models. Based on these observations, we have investigated whether mTOR is associated with HIF-1α-mediated VEGF expression in allergic asthma. In studies with the mTOR inhibitor rapamycin, we have elucidated the stimulatory role of a mTOR-HIF-1α-VEGF axis in allergic response. Next, the mechanisms by which mTOR is activated to modulate this response have been evaluated. mTOR is known to be regulated by phosphoinositide 3-kinase (PI3K/Akt or protein kinase C-delta (PKC δ in various cell types. Consistent with these, our results have revealed that suppression of PKC δ by rottlerin leads to the inhibition of PI3K/Akt activity and the subsequent blockade of a mTOR-HIF-1α-VEGF module, thereby attenuating typical asthmatic attack in a murine model. Thus, the present data indicate that PKC δ is necessary for the modulation of the PI3K/Akt/mTOR signaling cascade, resulting in a tight regulation of HIF-1α activity and VEGF expression. In conclusion, PKC δ may represent a valuable target for innovative therapeutic treatment of allergic airway disease.

  8. A Promising Recombinant Herpesvirus of Turkeys Vaccine Expressing PmpD-N of Chlamydia psittaci Based on Elongation Factor-1 Alpha Promoter

    Directory of Open Access Journals (Sweden)

    Shanshan Liu

    2017-12-01

    Full Text Available The obligate intracellular Gram-negative bacterium Chlamydia psittaci often causes avian chlamydiosis and influenza-like symptoms in humans. However, the commercial subunit C. psittaci vaccine could only provide a partial protection against avian chlamydiosis due to poor cellular immune response. In our previous study, a recombinant herpesvirus of turkeys (HVT-delivered vaccine against C. psittaci and Marek’s disease based on human cytomegalovirus (CMV promoter (rHVT-CMV-pmpD was developed and provided an effective protection against C. psittaci disease with less lesions and reduced chlamydial loads. In this study, we developed another recombinant HVT vaccine expressing the N-terminal fragment of PmpD (PmpD-N based on human elongation factor-1 alpha (EF-1α promoter (rHVT-EF-pmpD by modifying the HVT genome within a bacterial artificial chromosome. The related characterization of rHVT-EF-pmpD was evaluated in vitro in comparison with that of rHVT-CMV-pmpD. The expression of PmpD-N was determined by western blot. Under immunofluorescence microscopy, PmpD-N protein of both two recombinant viruses was located in the cytoplasm and on the cell surface. Growth kinetics of rHVT-EF-pmpD was comparable to that of rHVT-CMV-pmpD, and the growth rate of rHVT-EF-pmpD was apparently higher than that of rHVT-CMV-pmpD on 48, 72, and 120 h postinfection. Macrophages activated by rHVT-EF-pmpD could produce more nitric oxide and IL-6 than that activated by rHVT-CMV-pmpD. In this study, a recombinant HVT vaccine expressing PmpD-N based on EF-1α promoter was constructed successfully, and a further research in vivo was needed to analyze the vaccine efficacy.

  9. Knockdown of hypoxia-inducible factor-1 alpha reduces proliferation, induces apoptosis and attenuates the aggressive phenotype of retinoblastoma WERI-Rb-1 cells under hypoxic conditions.

    Science.gov (United States)

    Xia, Tian; Cheng, Hao; Zhu, Yu

    2014-01-01

    Hypoxia-inducible factor-1 alpha (HIF-1α) plays a critical role in tumor cell adaption to hypoxia by inducing the transcription of numerous genes. The role of HIF-1α in malignant retinoblastoma remains unclear. We analyzed the role of HIF-1α in WERI-Rb-1 retinoblastoma cells under hypoxic conditions. CoCl2 (125 mmol/L) was added to the culture media to mimic hypoxia. HIF-1α was silenced using siRNA. Gene and protein expression were measured by semi-quantitative RT-PCR and Western blotting. Cell cycle and apoptosis were analyzed by flow cytometry. Cell proliferation, adhesion and invasion were assayed using MTT, Transwell invasion, and cell adhesion assays respectively. Hypoxia significantly upregulated HIF-1α protein expression and the HIF-1α target genes VEGF, GLUT1, and Survivin mRNA. HIF-1α mRNA expression was not affected by hypoxia. Transfection of the siRNA expression plasmid pRNAT-CMV3.2/Neo-HIF-1α silenced HIF-1α by approximately 80% in hypoxic WERI-Rb-1 cells. The knockdown of HIF-1α under hypoxic conditions downregulated VEGF, GLUT1, and Survivin mRNA. It also inhibited proliferation, promoted apoptosis, induced the G0/G1 phase cell cycle arrest, and reduced the adhesion and invasion of WERI-Rb-1 cells. HIF-1α plays a major role in the survival and aggressive phenotype of retinoblastoma cells under hypoxic conditions. Targeting HIF-1α may be a promising therapeutic strategy for human malignant retinoblastoma.

  10. The association of interleukin-1alpha and interleukin-1beta polymorphisms with the risk of Graves' disease in a case-control study and meta-analysis.

    Science.gov (United States)

    Liu, Nan; Li, Xuejun; Liu, Changqin; Zhao, Yongju; Cui, Bin; Ning, Guang

    2010-04-01

    The proinflammatory cytokine interleukin (IL)-1 family has a central role in mediating inflammation and joint destruction in Graves' disease (GD). A number of studies, investigating rs1800587 (IL-1alpha, T-889 C) and rs16944 (IL-1beta, A-511 G) polymorphisms to test their possible association with GD and Graves' ophthalmopathy (GO), had inconsistent results. Our study aims to further evaluate the possible association of these two polymorphisms with GD and GO within the Han Chinese population using a case-control association study as well as a meta-analysis covering three previous studies from Taiwan, Iran, and Poland. Based on 760 Chinese GD patients, including 190 of GO cases among them, and 735 healthy control subjects, our data showed that the genotype or allele distributions of rs1800587 and rs16944 polymorphisms were significantly associated with GD (p = 0.003-0.049) and more so with GO (p = 0.001-0.021). The meta-analysis showed the risk-increasing effects for the TC and TT genotypes of rs1800587 in GD (odds ratio [OR] = 2.07, p = 0.03) and GO (OR = 3.22, p = 0.04), and a protective effect for the AA genotype of rs16944 in GD (OR = 0.70, p = 0.002) and GO (OR = 0.65, p = 0.02). The results confirmed that the rs1800587 (IL-alpha, T-889 C) and rs16944 (IL-1beta, A-511 G) polymorphisms may confer susceptibility to GD and GO in Asian population.

  11. The redox protein thioredoxin-1 (Trx-1) increases hypoxia-inducible factor 1alpha protein expression: Trx-1 overexpression results in increased vascular endothelial growth factor production and enhanced tumor angiogenesis.

    Science.gov (United States)

    Welsh, Sarah J; Bellamy, William T; Briehl, Margaret M; Powis, Garth

    2002-09-01

    Hypoxia-inducible factor 1 (HIF-1), a heterodimer of HIF-1alpha and HIF-1beta subunits, is a transcriptional activator central to the cellular response to low oxygen that includes metabolic adaptation, angiogenesis, metastasis, and inhibited apoptosis. Thioredoxin-1 (Trx-1) is a small redox protein overexpressed in a number of human primary tumors. We have examined the effects of Trx-1 on HIF activity and the activation of downstream genes. Stable transfection of human breast carcinoma MCF-7 cells with human Trx-1 caused a significant increase in HIF-1alpha protein levels under both normoxic (20% oxygen) and hypoxic (1% oxygen) conditions. Trx-1 increased hypoxia-induced HIF-1 transactivation activity measured using a luciferase reporter under the control of the hypoxia response element. Changes in HIF-1alpha mRNA levels did not account for the changes observed at the protein level, and HIF-1beta protein levels did not change. Trx-1 transfection also caused a significant increase in the protein products of hypoxia-responsive genes, including vascular endothelial growth factor (VEGF) and nitric oxide synthase 2 in a number of different cell lines (MCF-7 human breast and HT29 human colon carcinomas and WEHI7.2 mouse lymphoma cells) under both normoxic and hypoxic conditions. The pattern of expression of the different isoforms of VEGF was not changed by Trx-1. Transfection of a redox-inactive Trx-1 (C32S/C35S) markedly decreased levels of HIF-1alpha protein, HIF-1 transactivating activity, and VEGF protein in MCF-7 cells compared with empty vector controls. In vivo studies using WEHI7.2 cells transfected with Trx-1 showed significantly increased tumor VEGF and angiogenesis. The results suggest that Trx-1 increases HIF-1alpha protein levels in cancer cells and increases VEGF production and tumor angiogenesis.

  12. Increased expression of HIF-1alpha, VEGF-A and its receptors, MMP-2, TIMP-1, and ADAMTS-1 at the venous stenosis of arteriovenous fistula in a mouse model with renal insufficiency.

    Science.gov (United States)

    Misra, Sanjay; Shergill, Uday; Yang, Binxia; Janardhanan, Rajiv; Misra, Khamal D

    2010-08-01

    A mouse model of renal insufficiency with arteriovenous fistula (AVF) and venous stenosis was created. The authors tested the hypothesis that there is increased gene expression of hypoxia-inducible factor-1 alpha (HIF-1alpha); vascular endothelial growth factor-A (VEGF-A) and its receptors (VEGFR-1, -2); matrix metalloproteinase-2 (MMP-2), -9 (MMP-9); tissue inhibitor of metalloproteinase-1, -2 (TIMP-1, -2); and a disintegrin and metalloproteinase thrombospondin-1 (ADAMTS-1) at the venous stenosis. Nineteen male C57BL/6 mice underwent a left nephrectomy and a surgical occlusion of the right upper pole to induce renal function characterized in eight animals. Twenty eight days later, an AVF (n = 11) was created from the right carotid artery to ipsilateral jugular vein, and the mice were killed at day 7 (n = 4) and day 14 (n = 4). The outflow and control veins were removed for gene expression. Three mice were killed at day 28 for histologic analysis. The mean serum blood urea nitrogen level remained significantly elevated for 8 weeks when compared with baseline (P < .05). By day seven, there was a significant increase in the expression of HIF-1alpha, VEGF-A, VEGFR-1, VEGFR-2, MMP-2, TIMP-1, and ADAMTS-1 at the outflow vein, with HIF-1alpha and TIMP-1 levels significantly elevated at day 14 (P < .05). By day 28, the venous stenosis was characterized by a thickened vein wall and neointima. A mouse model of renal insufficiency with AVF was developed that had increased expression of HIF-1alpha, VEGF-A, VEGFR-1, VEGFR-2, MMP-2, TIMP-1, and ADAMTS-1 at the outflow vein with venous stenosis by day 28. Copyright (c) 2010 SIR. Published by Elsevier Inc. All rights reserved.

  13. Different ankle muscle coordination patterns and co-activation during quiet stance between young adults and seniors do not change after a bout of high intensity training.

    Science.gov (United States)

    Donath, Lars; Kurz, Eduard; Roth, Ralf; Zahner, Lukas; Faude, Oliver

    2015-03-04

    Available evidence suggests that young adults and seniors use different strategies to adjust for increasing body sway during quiet standing. Altered antagonist muscle co-activation and different ankle muscle coordination patterns may account for this finding. Consequently, we aimed at addressing whether aging leads to changes in neuromuscular coordination patterns as well as co-activation during quiet stance. We additionally investigated whether a bout of high intensity interval training additionally alters these patterns. Twenty healthy seniors (age: 70 ± 4 y) and twenty young adults (age: 27 ± 3 y) were enrolled in the present study. In between the testing procedures, four consecutive high-intensity intervals of 4 min duration at a target exercise intensity of 90 to 95% HRmax were completed on a treadmill. The total center of pressure (COP) path length displacement served as standing balance performance outcome. In order to assess ankle muscle coordination patterns, amplitude ratios (AR) were calculated for each muscle (e.g. tibialis anterior (TA) [%] = (TA × 100)/(gastrocnemius medialis (GM) + soleus (SOL) + peroneus longus (PL) + TA). The co-activation was calculated for the SOL and TA muscles computing the co-activation index (CAI = 2 × TA/TA + SOL). Seniors showed an inverted ankle muscle coordination pattern during single limb stance with eyes open (SLEO), compared to young adults (rest: GM, S: 15 ± 8% vs Y: 24 ± 9%; p = 0.03; SOL, S: 27 ± 14% vs Y: 37 ± 18%; p = 0.009; TA, S: 31 ± 13% vs Y: 13 ± 7%; p = 0.003). These patterns did not change after a high-intensity training session. A moderate correlation between amplitude ratios of the TA-contribution and postural sway was observed for seniors during SLEO (r = 0.61). Ankle co-activation was twofold elevated in seniors compared to young adults during SLEO (p Seniors with decreased postural control showed higher TA

  14. EFFECT OF ORTHOTIC SUBTALAR ALIGNMENT WITH CO-ACTIVATION EXERCISE FOR ALTERATION IN GAIT ENDURANCE IN A CHILD WITH CEREBRAL PALSYSINGLE CASE STUDY

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    K. Vadivelan

    2016-10-01

    Full Text Available Background: Energy cost of walking is two times higher in children with cerebral palsy when compared with normal children; this may be due to gait abnormalities.There is a negative influence on physical activity and early onsets of fatigue in activities of daily living are evident in cerebral palsy children and the reason for this is increase in energy cost of walking. Therefore, the treatment techniques which targets on correction of gait abnormalities and Energy conservation during walking are important to maintain orimprove independent functioning.The aim is to find out the effects of using Supra Malleolar Orthosis (SMO along with co-activation exercise in the increase of gait endurance and also to encourage independent skills and abilities in cerebral palsy child. Methods: A 14 years child with spastic hemiplegic cerebral palsy was treated with custom made supra malleolar orthotic which was designed with an orthotic support followed with specific exercises, co-activating dorsiflexors and plantar flexors actively and with assistance. The subject was made to do the co-activation exercises 3 days per week for 8 weeks. Step length, stride length, cadence, navicular drop test, medial arch height and calcaneal eversion were measured before starting the treatment and at the end of 8th week. Results: the results of treatment shows that there is an improvement in 2 minutes’ walk test from 7(pre-test to 13, step length from 22 (pre-test to 32,stride length from 36(pre-test to 47,cadence from 39 (pretest to 37 after the use of Supra Malleolar Orthosis (SMO and a co-activation exercises intervention. There was a clear and significant improvement noted in navicular drop test, medial arch height and calcaneal eversion after a period of 8 weeks use of orthosis and exercise intervention when compared with pre-test value. Conclusion: Orthotic subtalar alignment with co-acticvation exercises for alteration in gait endurance in a child is showing

  15. PGC-1-related coactivator (PRC) negatively regulates endothelial adhesion of monocytes via inhibition of NF κB activity

    Energy Technology Data Exchange (ETDEWEB)

    Chengye, Zhan; Daixing, Zhou, E-mail: dxzhou7246@hotmail.com; Qiang, Zhong; Shusheng, Li

    2013-09-13

    Highlights: •First time to display that LPS downregulate the expression of PRC. •First time to show that PRC inhibits the induction of VCAM-1 and E-selectin. •First time to show that PRC inhibit monocytes attachment to endothelial cells. •First time to display that PRC inhibits transcriptional activity of NF-κB. •PRC protects the respiration rate and suppresses the glycolysis rate against LPS. -- Abstract: PGC-1-related coactivator (PRC) is a growth-regulated transcriptional cofactor known to activate many of the nuclear genes specifying mitochondrial respiratory function. Endothelial dysfunction is a prominent feature found in many inflammatory diseases. Adhesion molecules, such as VCAM-1, mediate the attachment of monocytes to endothelial cells, thereby playing an important role in endothelial inflammation. The effects of PRC in regards to endothelial inflammation remain unknown. In this study, our findings show that PRC can be inhibited by the inflammatory cytokine LPS in cultured human umbilical vein endothelial cells (HUVECs). In the presence of LPS, the expression of endothelial cell adhesion molecular, such as VCAM1 and E-selectin, is found to be increased. These effects can be negated by overexpression of PRC. Importantly, monocyte adhesion to endothelial cells caused by LPS is significantly attenuated by PRC. In addition, overexpression of PRC protects mitochondrial metabolic function and suppresses the rate of glycolysis against LPS. It is also found that overexpression of PRC decreases the transcriptional activity of NF-κB. These findings suggest that PRC is a negative regulator of endothelial inflammation.

  16. Sustained expression of steroid receptor coactivator SRC-2/TIF-2 is associated with better prognosis in malignant pleural mesothelioma.

    LENUS (Irish Health Repository)

    Jennings, Cormac J

    2012-02-01

    INTRODUCTION: Estrogen receptor beta (ERbeta) overexpression by malignant pleural mesothelioma (MPM) tumor cells correlates with enhanced patient survival. ER-regulated transcription is mediated by the p160 family of steroid receptor coactivators (SRCs), and SRC isoform overexpression is associated with worse prognosis in many steroid-related malignancies. The aim of this study was to establish whether SRC isoform expression varied between individual MPM tumors with positive or negative prognostic significance. METHODS: Immunohistochemical analysis of tumor biopsies from 89 subjects with confirmed histological diagnosis of MPM and biopsies from 3 normal control subjects was performed to detect the expression of SRC-1, SRC-2 (TIF-2), SRC-3 (AIB-1), and ERbeta. Allred scores for expression of ERbeta and each of the SRCs were determined, and Kaplan-Meier survival curves were calculated to correlate biomarker expression, gender, and histology type with postdiagnosis survival. RESULTS: ERbeta and all the SRCs were expressed at high levels in normal pleural mesothelium, and expression of each biomarker was reduced or lost in a subset of the MPM subjects; however, postdiagnosis survival only significantly correlated with TIF-2 expression. Low or intermediate expression of TIF-2 correlated with reduced median postdiagnosis survival (9 months) compared with those subjects whose tumors highly expressed TIF-2 (20 months) (p = 0.036, log-rank test). CONCLUSIONS: Maintained high expression of TIF-2 in tumor cells is a positive prognostic indicator for postdiagnosis survival in patients with confirmed MPM. This is the first clinical study to correlate high TIF-2 expression with improved patient prognosis in any malignancy.

  17. Enforced expression of the transcriptional coactivator OBF1 impairs B cell differentiation at the earliest stage of development.

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    Alain Bordon

    Full Text Available OBF1, also known as Bob.1 or OCA-B, is a B lymphocyte-specific transcription factor which coactivates Oct1 and Oct2 on B cell specific promoters. So far, the function of OBF1 has been mainly identified in late stage B cell populations. The central defect of OBF1 deficient mice is a severely reduced immune response to T cell-dependent antigens and a lack of germinal center formation in the spleen. Relatively little is known about a potential function of OBF1 in developing B cells. Here we have generated transgenic mice overexpressing OBF1 in B cells under the control of the immunoglobulin heavy chain promoter and enhancer. Surprisingly, these mice have greatly reduced numbers of follicular B cells in the periphery and have a compromised immune response. Furthermore, B cell differentiation is impaired at an early stage in the bone marrow: a first block is observed during B cell commitment and a second differentiation block is seen at the large preB2 cell stage. The cells that succeed to escape the block and to differentiate into mature B cells have post-translationally downregulated the expression of transgene, indicating that expression of OBF1 beyond the normal level early in B cell development is deleterious. Transcriptome analysis identified genes deregulated in these mice and Id2 and Id3, two known negative regulators of B cell differentiation, were found to be upregulated in the EPLM and preB cells of the transgenic mice. Furthermore, the Id2 and Id3 promoters contain octamer-like sites, to which OBF1 can bind. These results provide evidence that tight regulation of OBF1 expression in early B cells is essential to allow efficient B lymphocyte differentiation.

  18. On the origin of muscle synergies: invariant balance in the co-activation of agonist and antagonist muscle pairs

    Directory of Open Access Journals (Sweden)

    Hiroaki eHirai

    2015-11-01

    Full Text Available Investigation of neural representation of movement planning has attracted the attention of neuroscientists, as it may reveal the sensorimotor transformation essential to motor control. The analysis of muscle synergies based on the activity of agonist-antagonist (AA muscle pairs may provide insight into such transformations, especially for a reference frame in the muscle space. In this study, we examined the AA concept using the following explanatory variables: the AA ratio, which is related to the equilibrium-joint angle, and the AA sum, which is associated with joint stiffness. We formulated muscle synergies as a function of AA sums, positing that muscle synergies are composite units of mechanical impedance. The AA concept can be regarded as another form of the equilibrium-point (EP hypothesis, and it can be extended to the concept of EP-based synergies. We introduce here a novel tool for analyzing the neurological and motor functions underlying human movements and review some initial insights from our results about the relationships between muscle synergies, endpoint stiffness, and virtual trajectories (time series of EP. Our results suggest that (1 muscle synergies reflect an invariant balance in the co-activation of AA muscle pairs; (2 each synergy represents the basis for the radial, tangential, and null movements of the virtual trajectory in the polar coordinates centered on the specific joint at the base of the body; and (3 the alteration of muscle synergies (for example, due to spasticity or rigidity following neurological injury results in significant distortion of endpoint stiffness and concomitant virtual trajectories. These results indicate that muscle synergies (i.e., the balance of muscle mechanical impedance are essential for motor control.

  19. On the Origin of Muscle Synergies: Invariant Balance in the Co-activation of Agonist and Antagonist Muscle Pairs.

    Science.gov (United States)

    Hirai, Hiroaki; Miyazaki, Fumio; Naritomi, Hiroaki; Koba, Keitaro; Oku, Takanori; Uno, Kanna; Uemura, Mitsunori; Nishi, Tomoki; Kageyama, Masayuki; Krebs, Hermano Igo

    2015-01-01

    Investigation of neural representation of movement planning has attracted the attention of neuroscientists, as it may reveal the sensorimotor transformation essential to motor control. The analysis of muscle synergies based on the activity of agonist-antagonist (AA) muscle pairs may provide insight into such transformations, especially for a reference frame in the muscle space. In this study, we examined the AA concept using the following explanatory variables: the AA ratio, which is related to the equilibrium-joint angle, and the AA sum, which is associated with joint stiffness. We formulated muscle synergies as a function of AA sums, positing that muscle synergies are composite units of mechanical impedance. The AA concept can be regarded as another form of the equilibrium-point (EP) hypothesis, and it can be extended to the concept of EP-based synergies. We introduce, here, a novel tool for analyzing the neurological and motor functions underlying human movements and review some initial insights from our results about the relationships between muscle synergies, endpoint stiffness, and virtual trajectories (time series of EP). Our results suggest that (1) muscle synergies reflect an invariant balance in the co-activation of AA muscle pairs; (2) each synergy represents the basis for the radial, tangential, and null movements of the virtual trajectory in the polar coordinates centered on the specific joint at the base of the body; and (3) the alteration of muscle synergies (for example, due to spasticity or rigidity following neurological injury) results in significant distortion of endpoint stiffness and concomitant virtual trajectories. These results indicate that muscle synergies (i.e., the balance of muscle mechanical impedance) are essential for motor control.

  20. Protein expression profiling of inflammatory mediators in human temporal lobe epilepsy reveals co-activation of multiple chemokines and cytokines

    Directory of Open Access Journals (Sweden)

    Kan Anne A

    2012-08-01

    Full Text Available Abstract Mesial temporal lobe epilepsy (mTLE is a chronic and often treatment-refractory brain disorder characterized by recurrent seizures originating from the hippocampus. The pathogenic mechanisms underlying mTLE remain largely unknown. Recent clinical and experimental evidence supports a role of various inflammatory mediators in mTLE. Here, we performed protein expression profiling of 40 inflammatory mediators in surgical resection material from mTLE patients with and without hippocampal sclerosis, and autopsy controls using a multiplex bead-based immunoassay. In mTLE patients we identified 21 upregulated inflammatory mediators, including 10 cytokines and 7 chemokines. Many of these upregulated mediators have not previously been implicated in mTLE (for example, CCL22, IL-7 and IL-25. Comparing the three patient groups, two main hippocampal expression patterns could be distinguished, pattern I (for example, IL-10 and IL-25 showing increased expression in mTLE + HS patients compared to mTLE-HS and controls, and pattern II (for example, CCL4 and IL-7 showing increased expression in both mTLE groups compared to controls. Upregulation of a subset of inflammatory mediators (for example, IL-25 and IL-7 could not only be detected in the hippocampus of mTLE patients, but also in the neocortex. Principle component analysis was used to cluster the inflammatory mediators into several components. Follow-up analyses of the identified components revealed that the three patient groups could be discriminated based on their unique expression profiles. Immunocytochemistry showed that IL-25 IR (pattern I and CCL4 IR (pattern II were localized in astrocytes and microglia, whereas IL-25 IR was also detected in neurons. Our data shows co-activation of multiple inflammatory mediators in hippocampus and neocortex of mTLE patients, indicating activation of multiple pro- and anti-epileptogenic immune pathways in this disease.

  1. Functional analysis of TamA, a coactivator of nitrogen-regulated gene expression in Aspergillus nidulans.

    Science.gov (United States)

    Small, A J; Todd, R B; Zanker, M C; Delimitrou, S; Hynes, M J; Davis, M A

    2001-06-01

    The tam A gene of Aspergillus nidulans encodes a 739-amino acid protein with similarity to Uga35p/Dal81p/DurLp of Saccharomyces cerevisiae. It has been proposed that TamA functions as a co-activator of AreA, the major nitrogen regulatory protein in A. nidulans. Because AreA functions as a transcriptional activator under nitrogen-limiting conditions, we investigated whether TamA was also present in the nucleus. We found that a GFP-TamA fusion protein was predominantly localised to the nucleus in the presence and absence of ammonium, and that AreA was not required for this distribution. As the predicted DNA-binding domain of TamA is not essential for function, we have used a number of approaches to further define functionally important regions. We have cloned the tamA gene of A. oryzae and compared its functional and sequence characteristics with those of A. nidulans tamA and S. cerevisiae UGA35/DAL81/DURL. The Aspergillus homologues are highly conserved and functionally interchangeable, whereas the S. cerevisiae gene does not complement a tamA mutant when expressed in A. nidulans. Uga35p/Dal81p/DurLp was also found to be unable to recruit AreA. The sequence changes in a number of tamA mutant alleles were determined, and altered versions of TamA were tested for tamA complementation and interaction with AreA. Changes in most regions of TamA appeared to destroy its function, suggesting that the overall conformation of the protein may be critical for its activity.

  2. SPBP is a sulforaphane induced transcriptional coactivator of NRF2 regulating expression of the autophagy receptor p62/SQSTM1.

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    Sagar Ramesh Darvekar

    Full Text Available Organisms exposed to oxidative stress respond by orchestrating a stress response to prevent further damage. Intracellular levels of antioxidant agents increase, and damaged components are removed by autophagy induction. The KEAP1-NRF2 signaling pathway is the main pathway responsible for cell defense against oxidative stress and for maintaining the cellular redox balance at physiological levels. Sulforaphane, an isothiocyanate derived from cruciferous vegetables, is a potent inducer of KEAP1-NRF2 signaling and antioxidant response element driven gene expression. In this study, we show that sulforaphane enhances the expression of the transcriptional coregulator SPBP. The expression curve peaks 6-8 hours post stimulation, and parallels the sulforaphane-induced expression of NRF2 and the autophagy receptor protein p62/SQSTM1. Reporter gene assays show that SPBP stimulates the expression of p62/SQSTM1 via ARE elements in the promoter region, and siRNA mediated knock down of SPBP significantly decreases the expression of p62/SQSTM1 and the formation of p62/SQSTM1 bodies in HeLa cells. Furthermore, SPBP siRNA reduces the sulforaphane induced expression of NRF2, and the expression of the autophagy marker protein LC3B. Both these proteins contain ARE-like elements in their promoter regions. Over-expressed SPBP and NRF2 acts synergistically on the p62/SQSTM1 promoter and colocalize in nuclear speckles in HeLa cells. Collectively, these results suggest that SPBP is a coactivator of NRF2, and hence may be important for securing enhanced and sustained expression of NRF2 induced genes such as proteins involved in selective autophagy.

  3. Molecular anatomy of CCR5 engagement by physiologic and viral chemokines and HIV-1 envelope glycoproteins: differences in primary structural requirements for RANTES, MIP-1 alpha, and vMIP-II Binding.

    Science.gov (United States)

    Navenot, J M; Wang, Z X; Trent, J O; Murray, J L; Hu, Q X; DeLeeuw, L; Moore, P S; Chang, Y; Peiper, S C

    2001-11-09

    Molecular analysis of CCR5, the cardinal coreceptor for HIV-1 infection, has implicated the N-terminal extracellular domain (N-ter) and regions vicinal to the second extracellular loop (ECL2) in this activity. It was shown that residues in the N-ter are necessary for binding of the physiologic ligands, RANTES (CCL5) and MIP-1 alpha (CCL3). vMIP-II, encoded by the Kaposi's sarcoma-associated herpesvirus, is a high affinity CCR5 antagonist, but lacks efficacy as a coreceptor inhibitor. Therefore, we compared the mechanism for engagement by vMIP-II of CCR5 to its interaction with physiologic ligands. RANTES, MIP-1 alpha, and vMIP-II bound CCR5 at high affinity, but demonstrated partial cross-competition. Characterization of 15 CCR5 alanine scanning mutants of charged extracellular amino acids revealed that alteration of acidic residues in the distal N-ter abrogated binding of RANTES, MIP-1 alpha, and vMIP-II. Whereas mutation of residues in ECL2 of CCR5 dramatically reduced the binding of RANTES and MIP-1 alpha and their ability to induce signaling, interaction with vMIP-II was not altered by any mutation in the exoloops of the receptor. Paradoxically, monoclonal antibodies to N-ter epitopes did not block chemokine binding, but those mapped to ECL2 were effective inhibitors. A CCR5 chimera with the distal N-ter residues of CXCR2 bound MIP-1 alpha and vMIP-II with an affinity similar to that of the wild-type receptor. Engagement of CCR5 by vMIP-II, but not RANTES or MIP-1 alpha blocked the binding of monoclonal antibodies to the receptor, providing additional evidence for a distinct mechanism for viral chemokine binding. Analysis of the coreceptor activity of randomly generated mouse-human CCR5 chimeras implicated residues in ECL2 between H173 and V197 in this function. RANTES, but not vMIP-II blocked CCR5 M-tropic coreceptor activity in the fusion assay. The insensitivity of vMIP-II binding to mutations in ECL2 provides a potential rationale to its inefficiency as an

  4. Diffuse glomerular nodular lesions in diabetic pigs carrying a dominant-negative mutant hepatocyte nuclear factor 1-alpha, an inheritant diabetic gene in humans.

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    Satoshi Hara

    Full Text Available Glomerular nodular lesions, known as Kimmelstiel-Wilson nodules, are a pathological hallmark of progressive human diabetic nephropathy. We have induced severe diabetes in pigs carrying a dominant-negative mutant hepatocyte nuclear factor 1-alpha (HNF1α P291fsinsC, a maturity-onset diabetes of the young type-3 (MODY3 gene in humans. In this model, glomerular pathology revealed that formation of diffuse glomerular nodules commenced as young as 1 month of age and increased in size and incidence until the age of 10 months, the end of the study period. Immunohistochemistry showed that the nodules consisted of various collagen types (I, III, IV, V and VI with advanced glycation end-product (AGE and Nε-carboxymethyl-lysine (CML deposition, similar to those in human diabetic nodules, except for collagen type I. Transforming growth factor-beta (TGF-β was also expressed exclusively in the nodules. The ultrastructure of the nodules comprised predominant interstitial-type collagen deposition arising from the mesangial matrices. Curiously, these nodules were found predominantly in the deep cortex. However, diabetic pigs failed to show any of the features characteristic of human diabetic nephropathy; e.g., proteinuria, glomerular basement membrane thickening, exudative lesions, mesangiolysis, tubular atrophy, interstitial fibrosis, and vascular hyalinosis. The pigs showed only Armanni-Ebstein lesions, a characteristic tubular manifestation in human diabetes. RT-PCR analysis showed that glomeruli in wild-type pigs did not express endogenous HNF1α and HNF1β, indicating that mutant HNF1α did not directly contribute to glomerular nodular formation in diabetic pigs. In conclusion, pigs harboring the dominant-negative mutant human MODY3 gene showed reproducible and distinct glomerular nodules, possibly due to AGE- and CML-based collagen accumulation. Although the pathology differed in several respects from that of human glomerular nodular lesions, the

  5. Initial results of hypoxia imaging using 1-{alpha}-d-(5-deoxy-5-[{sup 18}F]-fluoroarabinofuranosyl)-2-nitroimidazole ({sup 18}F-FAZA)

    Energy Technology Data Exchange (ETDEWEB)

    Postema, Ernst J.; McEwan, Alexander J.B.; Riauka, Terence A.; Kumar, Piyush; Richmond, Dacia A.; Abrams, Douglas N. [University of Alberta, Department of Oncology, Edmonton, Alberta (Canada); Wiebe, Leonard I. [University of Alberta, Faculty of Pharmacy and Pharmaceutical Sciences, Edmonton, Alberta (Canada)

    2009-10-15

    Tumour hypoxia is thought to play a significant role in the outcome of solid tumour therapy. Positron emission tomography (PET) is the best-validated noninvasive technique able to demonstrate the presence of hypoxia in vivo. The locally developed PET tracer for imaging hypoxia, 1-{alpha}-d-(5-deoxy-5-[{sup 18}F]-fluoroarabinofuranosyl)-2-nitroimidazole ({sup 18}F-FAZA), has been shown to accumulate in experimental models of tumour hypoxia and to clear rapidly from the circulation and nonhypoxic tissues. The safety and general biodistribution patterns of this radiopharmaceutical in patients with squamous cell carcinoma of the head and neck (HNSCC), small-cell lung cancer (SCLC) or non-small-cell lung cancer (NSCLC), malignant lymphoma, and high-grade gliomas, were demonstrated in this study. Patients with known primary or suspected metastatic HNSCC, SCLC or NSCLC, malignant lymphoma or high-grade gliomas were dosed with 5.2 MBq/kg of {sup 18}F-FAZA, then scanned 2-3 h after injection using a PET or PET/CT scanner. Images were interpreted by three experienced nuclear medicine physicians. The location and relative uptake scores (graded 0 to 4) of normal and abnormal {sup 18}F-FAZA biodistribution patterns, the calculated tumour-to-background (T/B) ratio, and the maximum standardized uptake value were recorded. Included in the study were 50 patients (32 men, 18 women). All seven patients with high-grade gliomas showed very high uptake of {sup 18}F-FAZA in the primary tumour. In six out of nine patients with HNSCC, clear uptake of {sup 18}F-FAZA was observed in the primary tumour and/or the lymph nodes in the neck. Of the 21 lymphoma patients (15 with non-Hodgkin's lymphoma and 6 with Hodgkin's disease), 3 demonstrated moderate lymphoma-related uptake. Of the 13 lung cancer patients (12 NSCLC, 1 SCLC), 7 had increased {sup 18}F-FAZA uptake in the primary lung tumour. No side effects of the administration of {sup 18}F-FAZA were observed. This study suggests

  6. Association of hypoxia inducible factor-1 alpha gene polymorphism with both type 1 and type 2 diabetes in a Caucasian (Hungarian sample

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    Panczel Pal

    2009-08-01

    Full Text Available Abstract Background Hypoxia inducible factor-1 alpha (HIF-1α is a transcription factor that plays an important role in neo-vascularisation, embryonic pancreas beta-cell mass development, and beta cell protection. Recently a non synonymous single nucleotide polymorphism (g.C45035T SNP, rs11549465 of HIF-1α gene, resulting in the p.P582S amino acid change has been shown to be associated with type 2 diabetes (T2DM in a Japanese population. Our aim was to replicate these findings on a Caucasian (Hungarian population, as well as to study whether this genetic effect is restricted to T2DM or can be expanded to diabetes in general. Methods A large Caucasian sample (N = 890 was recruited including 370 T2DM, 166 T1DM and 354 healthy subjects. Genotyping was validated by two independent methods: a restriction fragment analysis (RFLP and a real time PCR using TaqMan probes. An overestimation of heterozygotes by RFLP was observed as a consequence of a nearby SNP (rs34005929. Therefore genotyping results of the justified TaqMan system were accepted. The measured genotype distribution corresponded to Hardy-Weinberg equilibrium (P = 0.740 Results As the TT genotype was extremely rare in the population (0.6% in clinical sample and 2.5% in controls, the genotypes were grouped as T absent (CC and T present (CT and TT. Genotype-wise analysis showed a significant increase of T present group in controls (24.0% as compared to patients (16.8%, P = 0.008. This genetic effect was demonstrated in the separated samples of type 1 (15.1%, P = 0.020, and also in type 2 (17.6%, P = 0.032 diabetes. Allele-wise analysis gave identical results showing a higher frequency of the T allele in the control sample (13.3% than in the clinical sample (8.7%, P = 0.002 with similar results in type 1 (7.8%, P = 0.010 and type 2 (9.1%, P = 0.011 diabetes. The odds ratio for diabetes (either type 1 or 2 was 1.56 in the presence of the C allele. Conclusion We confirmed the protective effect

  7. PPARa and PPAR¿ coactivation rapidly induces Egr-1 in the nuclei of the dorsal and ventral urinary bladder and kidney pelvis urothelium of rats

    DEFF Research Database (Denmark)

    Egerod, Frederikke Lihme; Svendsen, Jette Eldrup; Hinley, Jennifer

    2009-01-01

    in the dorsal and ventral bladder urothelium, arguing against involvement of urinary solids. Egr-1 induction sometimes occurred in a localized fashion, indicating physiological microheterogeneity in the urothelium. The rapid kinetics supported that Egr-1 induction occurred as a result of pharmacological...... activation of PPAR alpha and PPAR gamma, which are coexpressed at high levels in the rat urothelium. Finally, our demonstration of a nuclear localization supports that the Egr-1 induced by PPAR alpha and PPAR gamma coactivation in the rat urothelium may be biologically active....

  8. Drought prediction using co-active neuro-fuzzy inference system, validation, and uncertainty analysis (case study: Birjand, Iran)

    Science.gov (United States)

    Memarian, Hadi; Pourreza Bilondi, Mohsen; Rezaei, Majid

    2016-08-01

    This work aims to assess the capability of co-active neuro-fuzzy inference system (CANFIS) for drought forecasting of Birjand, Iran through the combination of global climatic signals with rainfall and lagged values of Standardized Precipitation Index (SPI) index. Using stepwise regression and correlation analyses, the signals NINO 1 + 2, NINO 3, Multivariate Enso Index, Tropical Southern Atlantic index, Atlantic Multi-decadal Oscillation index, and NINO 3.4 were recognized as the effective signals on the drought event in Birjand. Based on the results from stepwise regression analysis and regarding the processor limitations, eight models were extracted for further processing by CANFIS. The metrics P-factor and D-factor were utilized for uncertainty analysis, based on the sequential uncertainty fitting algorithm. Sensitivity analysis showed that for all models, NINO indices and rainfall variable had the largest impact on network performance. In model 4 (as the model with the lowest error during training and testing processes), NINO 1 + 2(t-5) with an average sensitivity of 0.7 showed the highest impact on network performance. Next, the variables rainfall, NINO 1 + 2(t), and NINO 3(t-6) with the average sensitivity of 0.59, 0.28, and 0.28, respectively, could have the highest effect on network performance. The findings based on network performance metrics indicated that the global indices with a time lag represented a better correlation with El Niño Southern Oscillation (ENSO). Uncertainty analysis of the model 4 demonstrated that 68 % of the observed data were bracketed by the 95PPU and D-Factor value (0.79) was also within a reasonable range. Therefore, the fourth model with a combination of the input variables NINO 1 + 2 (with 5 months of lag and without any lag), monthly rainfall, and NINO 3 (with 6 months of lag) and correlation coefficient of 0.903 (between observed and simulated SPI) was selected as the most accurate model for drought forecasting using CANFIS

  9. Involvement of TORC2, a CREB co-activator, in the in vivo-specific transcriptional control of HTLV-1

    Directory of Open Access Journals (Sweden)

    Furuta Rika A

    2009-08-01

    Full Text Available Abstract Background Human T-cell leukemia virus type 1 (HTLV-1 causes adult T -cell leukemia (ATL but the expression of HTLV-1 is strongly suppressed in the peripheral blood of infected people. However, such suppression, which may explain the long latency in the development of ATL, is readily reversible, and viral expression resumes quickly with ex vivo culture of infected T -cells. To investigate the mechanism of in vivo -specific transcriptional suppression, we established a mouse model in which mice were intraperitoneally administered syngeneic EL4 T -lymphoma cells transduced with a recombinant retrovirus expressing a GFP-Tax fusion protein, Gax, under the control of the HTLV-1 enhancer (EL4-Gax. Results Gax gene transcription was silenced in vivo but quickly up-regulated in ex vivo culture. Analysis of integrated Gax reporter gene demonstrated that neither CpG methylation of the promoter DNA nor histone modification was associated with the reversible suppression. ChIP-analysis of LTR under suppression revealed reduced promoter binding of TFIIB and Pol-II, but no change in the binding of CREB or CBP/p300 to the viral enhancer sequence. However, the expression of TORC2, a co-activator of CREB, decreased substantially in the EL4-Gax cells in vivo, and this returned to normal levels in ex vivo culture. The reduced expression of TORC2 was associated with translocation from the nucleus to the cytoplasm. A knock-down experiment with siRNA confirmed that TORC2 was the major functional protein of the three TORC-family proteins (TORC1, 2, 3 in EL4-Gax cells. Conclusion These results suggest that the TORC2 may play an important role in the in vivo -specific transcriptional control of HTLV-1. This study provides a new model for the reversible mechanism that suppresses HTLV-1 expression in vivo without the DNA methylation or hypoacetylated histones that is observed in the primary cells of most HTLV-1 -infected carriers and a substantial number of ATL

  10. Chronic peroxisome proliferator-activated receptor gamma (PPARgamma) activation of epididymally derived white adipocyte cultures reveals a population of thermogenically competent, UCP1-containing adipocytes molecularly distinct from classic brown adipocytes

    DEFF Research Database (Denmark)

    Petrovic, Natasa; Walden, Tomas B; Shabalina, Irina G

    2009-01-01

    The recent insight that brown adipocytes and muscle cells share a common origin and in this respect are distinct from white adipocytes has spurred questions concerning the origin and molecular characteristics of the UCP1-expressing cells observed in classic white adipose tissue depots under certain...... physiological or pharmacological conditions. Examining precursors from the purest white adipose tissue depot (epididymal), we report here that chronic treatment with the peroxisome proliferator-activated receptor gamma agonist rosiglitazone promotes not only the expression of PGC-1alpha and mitochondriogenesis...... associated with classic brown adipocytes (Zic1, Lhx8, Meox2, and characteristically PRDM16) or for myocyte-associated genes (myogenin and myomirs (muscle-specific microRNAs)) and retain white fat characteristics such as Hoxc9 expression. Co-culture experiments verify that the UCP1-expressing cells...

  11. Convergence role of transcriptional coactivator p300 and apparent modification on HMCs metabolic memory induced by high glucose

    Directory of Open Access Journals (Sweden)

    Hong SU

    2013-03-01

    Full Text Available Objective  To investigate the protein expression of transcriptional coactivator p300, acetylated histone H3 (Ac-H3 and Ac-H4 in human renal mesangial cell (HMCs as imitative "metabolic memory" in vitro, and explore the potential role of convergence point of p300. Methods  The HMCs were divided into the following groups: ① High glucose metabolic memory model: normal glucose group (NG, 5.5mmol/L D-glucose×2d, high glucose group (HG, 25mmol/L D-glucose×2d, memory groups (M1, M2, M3, 25mmol/L D-glucose×2days + 5.5mmol/L D-glucose×3d, 6d or 9d, persisting normal glucose group (NG, 5.5mmol/L D-glucose×9d. ② Advanced glycation end products memory model: normal glucose group (NG, 5.5mmol/ L D-glucose×2d, NG+AGEs group (AGEs, 5.5mmol/L D-glucose+250µg/ml AGEs×2d; AGEs memory group (AGEs-M, 5.5mmol/L D-glucose + 250µg/ml AGEs×2d + 5.5mmol/L D-glucose×3d; BSA control group (NG+BSA, 5.5mmol/L D-glucose + 250µg/ml BSA×2d. ③ H2O2 was used to simulate oxidative stress memory model: normal glucose group (NG, 5.5mmol/L D-glucose×2d, NG+H2O2 group (H2O2, 5.5mmol/L D-glucose +100µmol/L H2O2×30min; H2O2 memory group [(5.5mmol/ L D-glucose + 100µmol/L H2O2×30min + 5.5mmol/L D-glucose×3d]; normal glucose control group (NG3, 5.5mmol/L D-glucose×3d. ④ Transfection with PKCβ2 memory model: normal glucose group (NG, 5.5mmol/L D-glucose×2d; high glucose group (HG, 25mmol/L D-glucose×2d; memory group (M, 25mmol/L D-glucose×2d + 5.5mmol/L D-glucose×3d; Ad5-null memory group (HN, 25mmol/L D-glucose + Ad5-null×2d + 5.5mmol/L D-glucose×3d; PKCβ2 memory group (PO, 25mmol/L D-glucose + Ad5-PKCβ2×2d + 5.5mmol/L D-glucose×3d; inhibitor of PKCβ2 memory group (PI, 25mmol/L D-glucose×2d + 10µmol/L CGP53353 + 5.5mmol/L D-glucose×3d. The expression of intracellular reactive oxygen species (ROS was detected by fluorescence microscope and fluorescence microplate reader. The expression levels of p300, Ac-H3, Ac-H4 and PKCβ2 proteins were

  12. Hepatitis C virus core protein regulates p300/CBP co-activation function. Possible role in the regulation of NF-AT1 transcriptional activity

    International Nuclear Information System (INIS)

    Gomez-Gonzalo, Marta; Benedicto, Ignacio; Carretero, Marta; Lara-Pezzi, Enrique; Maldonado-Rodriguez, Alejandra; Moreno-Otero, Ricardo; Lai, Michael M.C.; Lopez-Cabrera, Manuel

    2004-01-01

    Hepatitis C virus (HCV) core is a viral structural protein; it also participates in some cellular processes, including transcriptional regulation. However, the mechanisms of core-mediated transcriptional regulation remain poorly understood. Oncogenic virus proteins often target p300/CBP, a known co-activator of a wide variety of transcription factors, to regulate the expression of cellular and viral genes. Here we demonstrate, for the first time, that HCV core protein interacts with p300/CBP and enhances both its acetyl-transferase and transcriptional activities. In addition, we demonstrate that nuclear core protein activates the NH 2 -terminal transcription activation domain (TAD) of NF-AT1 in a p300/CBP-dependent manner. We propose a model in which core protein regulates the co-activation function of p300/CBP and activates NF-AT1, and probably other p300/CBP-regulated transcription factors, by a novel mechanism involving the regulation of the acetylation state of histones and/or components of the transcriptional machinery

  13. A liver X receptor (LXR)-β alternative splicing variant (LXRBSV) acts as an RNA co-activator of LXR-β

    International Nuclear Information System (INIS)

    Hashimoto, Koshi; Ishida, Emi; Matsumoto, Shunichi; Shibusawa, Nobuyuki; Okada, Shuichi; Monden, Tsuyoshi; Satoh, Tetsurou; Yamada, Masanobu; Mori, Masatomo

    2009-01-01

    We report the isolation and functional characterization of a novel transcriptional co-activator, termed LXRBSV. LXRBSV is an alternative splicing variant of liver X receptor (LXR)-β LXRBSV has an intronic sequence between exons 2 and 3 in the mouse LXR-β gene. The LXRBSV gene is expressed in various tissues including the liver and brain. We sub-cloned LXRBSV into pSG5, a mammalian expression vector, and LXRBSV in pSG5 augmented human Sterol Response Element Binding Protein (SREBP)-1c promoter activity in HepG2 cells in a ligand (TO901317) dependent manner. The transactivation mediated by LXRBSV is selective for LXR-β. The LXRBSV protein was deduced to be 64 amino acids in length; however, a GAL4-LXRBSV fusion protein was not able to induce transactivation. Serial deletion constructs of LXRBSV demonstrated that the intronic sequence inserted in LXRBSV is required for its transactivation activity. An ATG mutant of LXRBSV was able to induce transactivation as wild type. Furthermore, LXRBSV functions in the presence of cycloheximide. Taken together, we have concluded that LXRBSV acts as an RNA transcript not as a protein. In the current study, we have demonstrated for the first time that an alternative splicing variant of a nuclear receptor acts as an RNA co-activator.

  14. Mediator 1 contributes to enamel mineralization as a coactivator for Notch1 signaling and stimulates transcription of the alkaline phosphatase gene.

    Science.gov (United States)

    Yoshizaki, Keigo; Hu, Lizhi; Nguyen, Thai; Sakai, Kiyoshi; Ishikawa, Masaki; Takahashi, Ichiro; Fukumoto, Satoshi; DenBesten, Pamela K; Bikle, Daniel D; Oda, Yuko; Yamada, Yoshihiko

    2017-08-18

    Tooth enamel is mineralized through the differentiation of multiple dental epithelia including ameloblasts and the stratum intermedium (SI), and this differentiation is controlled by several signaling pathways. Previously, we demonstrated that the transcriptional coactivator Mediator 1 (MED1) plays a critical role in enamel formation. For instance, conditional ablation of Med1 in dental epithelia causes functional changes in incisor-specific dental epithelial stem cells, resulting in mineralization defects in the adult incisors. However, the molecular mechanism by which Med1 deficiency causes these abnormalities is not clear. Here, we demonstrated that Med1 ablation causes early SI differentiation defects resulting in enamel hypoplasia of the Med1 -deficient molars. Med1 deletion prevented Notch1-mediated differentiation of the SI cells resulting in decreased alkaline phosphatase (ALPL), which is essential for mineralization. However, it does not affect the ability of ameloblasts to produce enamel matrix proteins. Using the dental epithelial SF2 cell line, we demonstrated that MED1 directly activates transcription of the Alpl gene through the stimulation of Notch1 signaling by forming a complex with cleaved Notch1-RBP-Jk on the Alpl promoter. These results suggest that MED1 may be essential for enamel matrix mineralization by serving as a coactivator for Notch1 signaling regulating transcription of the Alpl gene.

  15. Activation of Akt is essential for the propagation of mitochondrial respiratory stress signaling and activation of the transcriptional coactivator heterogeneous ribonucleoprotein A2.

    Science.gov (United States)

    Guha, Manti; Fang, Ji-Kang; Monks, Robert; Birnbaum, Morris J; Avadhani, Narayan G

    2010-10-15

    Mitochondrial respiratory stress (also called mitochondrial retrograde signaling) activates a Ca(2+)/calcineurin-mediated signal that culminates in transcription activation/repression of a large number of nuclear genes. This signal is propagated through activation of the regulatory proteins NFκB c-Rel/p50, C/EBPδ, CREB, and NFAT. Additionally, the heterogeneous ribonucleoprotein A2 (hnRNPA2) functions as a coactivator in up-regulating the transcription of Cathepsin L, RyR1, and Glut-4, the target genes of stress signaling. Activation of IGF1R, which causes a metabolic switch to glycolysis, cell invasiveness, and resistance to apoptosis, is a phenotypic hallmark of C2C12 myoblasts subjected to mitochondrial stress. In this study, we report that mitochondrial stress leads to increased expression, activation, and nuclear localization of Akt1. Mitochondrial respiratory stress also activates Akt1-gene expression, which involves hnRNPA2 as a coactivator, indicating a complex interdependency of these two factors. Using Akt1(-/-) mouse embryonic fibroblasts and Akt1 mRNA-silenced C2C12 cells, we show that Akt1-mediated phosphorylation is crucial for the activation and recruitment of hnRNPA2 to the enhanceosome complex. Akt1 mRNA silencing in mtDNA-depleted cells resulted in reversal of the invasive phenotype, accompanied by sensitivity to apoptotic stimuli. These results show that Akt1 is an important regulator of the nuclear transcriptional response to mitochondrial stress.

  16. Short-term, serum-free, static culture of cord blood-derived CD34+ cells: effects of FLT3-L and MIP-1alpha on in vitro expansion of hematopoietic progenitor cells.

    Science.gov (United States)

    Capmany, G; Querol, S; Cancelas, J A; García, J

    1999-08-01

    The use of ex vivo expanded cells has been suggested as a possible means to accelerate the speed of engraftment in cord blood (CB) transplantation. The aim of this study was to fix the optimal condition for the generation of committed progenitors without affecting the stem cell compartment. Analysis of the effects of FLT3-L and MIP-1alpha when combined with SCF, IL-3 and IL-6, in short-term (6 days), serum-free expansion cultures of CB-selected CD34+ cells. An important expansion was obtained that ranged between 8-15 times for CFU-GM, 21-51 times for the BFU-E/CFU-Mix population and 11 to 30 times for CD34+ cells assessed by flow cytometry. From the combinations tested, those in which FLT3-L was present had a significant increase in the expansion of committed progenitors, while the presence of MIP-1alpha had a detrimental effect on the generation of more differentiated cells. However, stem cell candidates assessed by week 5 CAFC assay could be maintained in culture when both MIP-1a and FLT3-L were present (up to 91% recovery). This culture system was also able to expand megakaryocytic precursors as determined by the co-expression of CD34 and CD61 antigens (45-70 times), in spite of the use of cytokines non-specific for the megakaryocytic lineage. The results obtained point to the combination of SCF, IL-3, IL-6, FLT3-L and MIP-1alpha as the best suited for a pre-clinical short-term serum-free static ex vivo expansion protocol of CB CD34+ cells, since it can generate large numbers of committed progenitor cells as well as maintaining week 5 CAFC.

  17. Long-term effects of intravenous 1 alpha (OH)D3 combined with CaCO3 and low-calcium dialysis on secondary hyperparathyroidism and biochemical bone markers in patients on chronic hemodialysis

    DEFF Research Database (Denmark)

    Brandi, L; Daugaard, H; Nielsen, P K

    1996-01-01

    doses of CaCO3 and to reduce the doses of an aluminium-containing oral phosphate binder. A decrease in p-Ca2+ during dialysis was induced, and special care had to focus on the compliance to CaCO3, in order not to aggravate the secondary hyperparathyroidism. (2) The combination of 'low......-terminal extension peptide) were examined in 54 patients on chronic hemodialysis with either normal or elevated PTH. Increasing doses of 1 alpha (OH)D3 were administered intravenously under careful control of p-Ca2+ and inorganic phosphate. Blood samples were obtained 1 week before the start of treatment...

  18. Endothelial cell markers in vascular neoplasms: an immunohistochemical study comparing factor VIII-related antigen, blood group specific antigens, 6-keto-PGF1 alpha, and Ulex europaeus 1 lectin.

    Science.gov (United States)

    Little, D; Said, J W; Siegel, R J; Fealy, M; Fishbein, M C

    1986-06-01

    Markers for endothelial cells including Ulex europaeus 1 lectin, blood group A, B, and H, and the prostaglandin metabolite 6-keto-PGF1 alpha were evaluated in paraffin secretions from formalin-fixed benign and malignant vascular neoplasms using a variety of immunohistochemical techniques, and results compared with staining for factor VIII-related antigen. Staining for Ulex appeared more sensitive than factor VIII-related antigen in identifying poorly differentiated neoplasms including haemangiosarcomas and spindle cell proliferations in Kaposi's sarcoma. Staining for blood group related antigens correlated with blood group in all cases. Ulex europaeus 1 lectin was the only marker for endothelial cells in lymphangiomas.

  19. Prognostic and predictive importance of the estrogen receptor coactivator AIB1 in a randomized trial comparing adjuvant letrozole and tamoxifen therapy in postmenopausal breast cancer

    DEFF Research Database (Denmark)

    Alkner, S; Jensen, Maj-Britt Raaby; Rasmussen, B B

    2017-01-01

    PURPOSE: To evaluate the estrogen receptor coactivator amplified in breast cancer 1 (AIB1) as a prognostic marker, as well as a predictive marker for response to adjuvant tamoxifen and/or aromatase inhibitors, in early estrogen receptor-positive breast cancer. METHOD: AIB1 was analyzed...... with immunohistochemistry in tissue microarrays of the Danish subcohort (N = 1396) of the International Breast Cancer Study Group's trial BIG 1-98 (randomization between adjuvant tamoxifen versus letrozole versus the sequence of the two drugs). RESULTS: Forty-six percent of the tumors had a high AIB1 expression. In line...... with previous studies, AIB1 correlated to a more aggressive tumor-phenotype (HER2 amplification and a high malignancy grade). High AIB1 also correlated to higher estrogen receptor expression (80-100 vs. 1-79%), and ductal histological type. High AIB1 expression was associated with a poor disease-free survival...

  20. Multichannel Luminescence Properties of Mixed-Valent Eu2+/Eu3+ Coactivated SrAl3BO7 Nanocrystalline Phosphors for Near-UV LEDs.

    Science.gov (United States)

    Liu, Xiaoming; Xie, Weijie; Lü, Ying; Feng, Jingchun; Tang, Xinghua; Lin, Jun; Dai, Yuhua; Xie, Yu; Yan, Liushui

    2017-11-20

    Up to now, orchestrating the coexistence of Eu 2+ and Eu 3+ activators in a single host lattice has been an extremely difficult task, especially for the appearance of the characteristic emission of Eu 2+ and Eu 3+ in order to generate white light. Nevertheless, here we demonstrate a new Eu 2+ /Eu 3+ coactivated SrAl 3 BO 7 nanocrystalline phosphor with abundant and excellent multichannel luminescence properties. A series of Eu 2+ /Eu 3+ coactivated SrAl 3 BO 7 nanocrystalline phosphors were prepared through a Pechini-type sol-gel method followed by a reduction process. With excitation of UV/NUV light, the prepared SrAl 3 BO 7 :Eu 2+ ,Eu 3+ phosphors show not only the characteristic f-f transitions of Eu 3+ ion ( 5 D J → 7 F J,J' , J, J' = 0-3), but also the 5d → 4f transitions of Eu 2+ ion with comparable intensity from 400 to 700 nm in the whole visible spectral region. The luminescence color of the SrAl 3 BO 7 :Eu 2+ ,Eu 3+ phosphor can be tuned from blue, blue-green, white, and orange to orange-red by changing the excitation wavelength, the overall doping concentration of europium ions (Eu 2+ , Eu 3+ ), and the relative ratio of Eu 2+ to Eu 3+ ions to some extent. A single-phase white-light emission has been realized in SrAl 3 BO 7 :Eu 2+ ,Eu 3+ phosphor. The obtained SrAl 3 BO 7 :Eu 2+ ,Eu 3+ phosphor has potential application in the area of NUV white-light-emitting diodes.

  1. Cell cycle-dependent expression of Dub3, Nanog and the p160 family of nuclear receptor coactivators (NCoAs in mouse embryonic stem cells.

    Directory of Open Access Journals (Sweden)

    Siem van der Laan

    Full Text Available Pluripotency of embryonic stem cells (ESC is tightly regulated by a network of transcription factors among which the estrogen-related receptor β (Esrrb. Esrrb contributes to the relaxation of the G1 to S-phase (G1/S checkpoint in mouse ESCs by transcriptional control of the deubiquitylase Dub3 gene, contributing to Cdc25A persistence after DNA damage. We show that in mESCs, Dub3 gene expression is cell cycle regulated and is maximal prior G1/S transition. In addition, following UV-induced DNA damage in G1, Dub3 expression markedly increases in S-phase also suggesting a role in checkpoint recovery. Unexpectedly, we also observed cell cycle-regulation of Nanog expression, and not Oct4, reaching high levels prior to G1/S transition, finely mirroring Cyclin E1 fluctuations. Curiously, while Esrrb showed only limited cell-cycle oscillations, transcript levels of the p160 family of nuclear receptor coactivators (NCoAs displayed strong cell cycle-dependent fluctuations. Since NCoAs function in concert with Esrrb in transcriptional activation, we focussed on NCoA1 whose levels specifically increase prior onset of Dub3 transcription. Using a reporter assay, we show that NCoA1 potentiates Esrrb-mediated transcription of Dub3 and we present evidence of protein interaction between the SRC1 splice variant NCoA1 and Esrrb. Finally, we show a differential developmental regulation of all members of the p160 family during neural conversion of mESCs. These findings suggest that in mouse ESCs, changes in the relative concentration of a coactivator at a given cell cycle phase, may contribute to modulation of the transcriptional activity of the core transcription factors of the pluripotent network and be implicated in cell fate decisions upon onset of differentiation.

  2. Cell cycle-dependent expression of Dub3, Nanog and the p160 family of nuclear receptor coactivators (NCoAs) in mouse embryonic stem cells.

    Science.gov (United States)

    van der Laan, Siem; Golfetto, Eleonora; Vanacker, Jean-Marc; Maiorano, Domenico

    2014-01-01

    Pluripotency of embryonic stem cells (ESC) is tightly regulated by a network of transcription factors among which the estrogen-related receptor β (Esrrb). Esrrb contributes to the relaxation of the G1 to S-phase (G1/S) checkpoint in mouse ESCs by transcriptional control of the deubiquitylase Dub3 gene, contributing to Cdc25A persistence after DNA damage. We show that in mESCs, Dub3 gene expression is cell cycle regulated and is maximal prior G1/S transition. In addition, following UV-induced DNA damage in G1, Dub3 expression markedly increases in S-phase also suggesting a role in checkpoint recovery. Unexpectedly, we also observed cell cycle-regulation of Nanog expression, and not Oct4, reaching high levels prior to G1/S transition, finely mirroring Cyclin E1 fluctuations. Curiously, while Esrrb showed only limited cell-cycle oscillations, transcript levels of the p160 family of nuclear receptor coactivators (NCoAs) displayed strong cell cycle-dependent fluctuations. Since NCoAs function in concert with Esrrb in transcriptional activation, we focussed on NCoA1 whose levels specifically increase prior onset of Dub3 transcription. Using a reporter assay, we show that NCoA1 potentiates Esrrb-mediated transcription of Dub3 and we present evidence of protein interaction between the SRC1 splice variant NCoA1 and Esrrb. Finally, we show a differential developmental regulation of all members of the p160 family during neural conversion of mESCs. These findings suggest that in mouse ESCs, changes in the relative concentration of a coactivator at a given cell cycle phase, may contribute to modulation of the transcriptional activity of the core transcription factors of the pluripotent network and be implicated in cell fate decisions upon onset of differentiation.

  3. The PDZ-binding motif of Yes-associated protein is required for its co-activation of TEAD-mediated CTGF transcription and oncogenic cell transforming activity

    International Nuclear Information System (INIS)

    Shimomura, Tadanori; Miyamura, Norio; Hata, Shoji; Miura, Ryota; Hirayama, Jun; Nishina, Hiroshi

    2014-01-01

    Highlights: •Loss of the PDZ-binding motif inhibits constitutively active YAP (5SA)-induced oncogenic cell transformation. •The PDZ-binding motif of YAP promotes its nuclear localization in cultured cells and mouse liver. •Loss of the PDZ-binding motif inhibits YAP (5SA)-induced CTGF transcription in cultured cells and mouse liver. -- Abstract: YAP is a transcriptional co-activator that acts downstream of the Hippo signaling pathway and regulates multiple cellular processes, including proliferation. Hippo pathway-dependent phosphorylation of YAP negatively regulates its function. Conversely, attenuation of Hippo-mediated phosphorylation of YAP increases its ability to stimulate proliferation and eventually induces oncogenic transformation. The C-terminus of YAP contains a highly conserved PDZ-binding motif that regulates YAP’s functions in multiple ways. However, to date, the importance of the PDZ-binding motif to the oncogenic cell transforming activity of YAP has not been determined. In this study, we disrupted the PDZ-binding motif in the YAP (5SA) protein, in which the sites normally targeted by Hippo pathway-dependent phosphorylation are mutated. We found that loss of the PDZ-binding motif significantly inhibited the oncogenic transformation of cultured cells induced by YAP (5SA). In addition, the increased nuclear localization of YAP (5SA) and its enhanced activation of TEAD-dependent transcription of the cell proliferation gene CTGF were strongly reduced when the PDZ-binding motif was deleted. Similarly, in mouse liver, deletion of the PDZ-binding motif suppressed nuclear localization of YAP (5SA) and YAP (5SA)-induced CTGF expression. Taken together, our results indicate that the PDZ-binding motif of YAP is critical for YAP-mediated oncogenesis, and that this effect is mediated by YAP’s co-activation of TEAD-mediated CTGF transcription

  4. The PDZ-binding motif of Yes-associated protein is required for its co-activation of TEAD-mediated CTGF transcription and oncogenic cell transforming activity

    Energy Technology Data Exchange (ETDEWEB)

    Shimomura, Tadanori; Miyamura, Norio; Hata, Shoji; Miura, Ryota; Hirayama, Jun, E-mail: hirayama.dbio@mri.tmd.ac.jp; Nishina, Hiroshi, E-mail: nishina.dbio@mri.tmd.ac.jp

    2014-01-17

    Highlights: •Loss of the PDZ-binding motif inhibits constitutively active YAP (5SA)-induced oncogenic cell transformation. •The PDZ-binding motif of YAP promotes its nuclear localization in cultured cells and mouse liver. •Loss of the PDZ-binding motif inhibits YAP (5SA)-induced CTGF transcription in cultured cells and mouse liver. -- Abstract: YAP is a transcriptional co-activator that acts downstream of the Hippo signaling pathway and regulates multiple cellular processes, including proliferation. Hippo pathway-dependent phosphorylation of YAP negatively regulates its function. Conversely, attenuation of Hippo-mediated phosphorylation of YAP increases its ability to stimulate proliferation and eventually induces oncogenic transformation. The C-terminus of YAP contains a highly conserved PDZ-binding motif that regulates YAP’s functions in multiple ways. However, to date, the importance of the PDZ-binding motif to the oncogenic cell transforming activity of YAP has not been determined. In this study, we disrupted the PDZ-binding motif in the YAP (5SA) protein, in which the sites normally targeted by Hippo pathway-dependent phosphorylation are mutated. We found that loss of the PDZ-binding motif significantly inhibited the oncogenic transformation of cultured cells induced by YAP (5SA). In addition, the increased nuclear localization of YAP (5SA) and its enhanced activation of TEAD-dependent transcription of the cell proliferation gene CTGF were strongly reduced when the PDZ-binding motif was deleted. Similarly, in mouse liver, deletion of the PDZ-binding motif suppressed nuclear localization of YAP (5SA) and YAP (5SA)-induced CTGF expression. Taken together, our results indicate that the PDZ-binding motif of YAP is critical for YAP-mediated oncogenesis, and that this effect is mediated by YAP’s co-activation of TEAD-mediated CTGF transcription.

  5. Histogram analysis of ADC in rectal cancer: associations with different histopathological findings including expression of EGFR, Hif1-alpha, VEGF, p53, PD1, and KI 67. A preliminary study.

    Science.gov (United States)

    Meyer, Hans Jonas; Höhn, Annekathrin; Surov, Alexey

    2018-04-06

    Functional imaging modalities like Diffusion-weighted imaging are increasingly used to predict tumor behavior like cellularity and vascularity in different tumors. Histogram analysis is an emergent imaging analysis, in which every voxel is used to obtain a histogram and therefore statistically information about tumors can be provided. The purpose of this study was to elucidate possible associations between ADC histogram parameters and several immunhistochemical features in rectal cancer. Overall, 11 patients with histologically proven rectal cancer were included into the study. There were 2 (18.18%) females and 9 males with a mean age of 67.1 years. KI 67-index, expression of p53, EGFR, VEGF, and Hif1-alpha were semiautomatically estimated. The tumors were divided into PD1-positive and PD1-negative lesions. ADC histogram analysis was performed as a whole lesion measurement using an in-house matlab application. Spearman's correlation analysis revealed a strong correlation between EGFR expression and ADCmax (p=0.72, P=0.02). None of the vascular parameters (VEGF, Hif1-alpha) correlated with ADC parameters. Kurtosis and skewness correlated inversely with p53 expression (p=-0.64, P=0.03 and p=-0.81, P=0.002, respectively). ADCmedian and ADCmode correlated with Ki67 (p=-0.62, P=0.04 and p=-0.65, P=0.03, respectively). PD1-positive tumors showed statistically significant lower ADCmax values in comparison to PD1-negative tumors, 1.93 ± 0.36 vs 2.32 ± 0.47×10 -3 mm 2 /s, p=0.04. Several associations were identified between histogram parameter derived from ADC maps and EGFR, KI 67 and p53 expression in rectal cancer. Furthermore, ADCmax was different between PD1 positive and PD1 negative tumors indicating an important role of ADC parameters for possible future treatment prediction.

  6. P300/CBP acts as a coactivator to cartilage homeoprotein-1 (Cart1), paired-like homeoprotein, through acetylation of the conserved lysine residue adjacent to the homeodomain.

    Science.gov (United States)

    Iioka, Takashi; Furukawa, Keizo; Yamaguchi, Akira; Shindo, Hiroyuki; Yamashita, Shunichi; Tsukazaki, Tomoo

    2003-08-01

    The paired-like homeoprotein, Cart1, is involved in skeletal development. We describe here that the general coactivator p300/CBP controls the transcription activity of Cart1 through acetylation of a lysine residue that is highly conserved in other homeoproteins. Acetylation of this residue increases the interaction between p300/CBP and Cart1 and enhances its transcriptional activation. Cart1 encodes a paired-like homeoprotein expressed selectively in chondrocyte lineage during embryonic development. Although its target gene remains unknown, gene disruption studies have revealed that Cart1 plays an important role for craniofacial bone formation as well as limb development by cooperating with another homeoprotein, Alx4. In this report, we study the functional involvement of p300/CBP, coactivators with intrinsic histone acetyltransferase (HAT) activity, in the transcriptional control of Cart1. To study the transcription activity of Cart1, a reporter construct containing a putative Cart1 binding site was transiently transfected with the expression vectors of each protein. The interaction between p300/CBP and Cart1 was investigated by glutathione S-transferase (GST) pull-down, yeast two-hybrid, and immunoprecipitation assays. In vitro acetylation assay was performed with the recombinant p300-HAT domain and Cart1 in the presence of acetyl-CoA. p300 and CBP stimulate Cart1-dependent transcription activity, and this transactivation is inhibited by E1A and Tax, oncoproteins that suppress the activity of p300/CBP. Cart1 binds to p300 in vivo and in vitro, and this requires the homeodomain of Cart 1 and N-terminal 139 amino acids of p300. Confocal microscopy analysis shows that Cart1 recruits overexpressed and endogenous p300 to a Cart1-specific subnuclear compartment. Cart1 is acetylated in vivo and sodium butyrate and trichostatin A, histone deacetylase inhibitors, markedly enhance the transcription activity of Cart1. Deletion and mutagenesis analysis identifies the 131st

  7. A toll-like receptor 2 pathway regulates the Ppargc1a/b metabolic co-activators in mice with Staphylococcal aureus sepsis.

    Directory of Open Access Journals (Sweden)

    Timothy E Sweeney

    Full Text Available Activation of the host antibacterial defenses by the toll-like receptors (TLR also selectively activates energy-sensing and metabolic pathways, but the mechanisms are poorly understood. This includes the metabolic and mitochondrial biogenesis master co-activators, Ppargc1a (PGC-1α and Ppargc1b (PGC-1β in Staphylococcus aureus (S. aureus sepsis. The expression of these genes in the liver is markedly attenuated inTLR2(-/- mice and markedly accentuated in TLR4(-/- mice compared with wild type (WT mice. We sought to explain this difference by using specific TLR-pathway knockout mice to test the hypothesis that these co-activator genes are directly regulated through TLR2 signaling. By comparing their responses to S. aureus with WT mice, we found that MyD88-deficient and MAL-deficient mice expressed hepatic Ppargc1a and Ppargc1b normally, but that neither gene was activated in TRAM-deficient mice. Ppargc1a/b activation did not require NF-kβ, but did require an interferon response factor (IRF, because neither gene was activated in IRF-3/7 double-knockout mice in sepsis, but both were activated normally in Unc93b1-deficient (3d mice. Nuclear IRF-7 levels in TLR2(-/- and TLR4(-/- mice decreased and increased respectively post-inoculation and IRF-7 DNA-binding at the Ppargc1a promoter was demonstrated by chromatin immunoprecipitation. Also, a TLR2-TLR4-TRAM native hepatic protein complex was detected by immunoprecipitation within 6 h of S. aureus inoculation that could support MyD88-independent signaling to Ppargc1a/b. Overall, these findings disclose a novel MyD88-independent pathway in S. aureus sepsis that links TLR2 and TLR4 signaling in innate immunity to Ppargc1a/b gene regulation in a critical metabolic organ, the liver, by means of TRAM, TRIF, and IRF-7.

  8. A high-confidence interaction map identifies SIRT1 as a mediator of acetylation of USP22 and the SAGA coactivator complex.

    Science.gov (United States)

    Armour, Sean M; Bennett, Eric J; Braun, Craig R; Zhang, Xiao-Yong; McMahon, Steven B; Gygi, Steven P; Harper, J Wade; Sinclair, David A

    2013-04-01

    Although many functions and targets have been attributed to the histone and protein deacetylase SIRT1, a comprehensive analysis of SIRT1 binding proteins yielding a high-confidence interaction map has not been established. Using a comparative statistical analysis of binding partners, we have assembled a high-confidence SIRT1 interactome. Employing this method, we identified the deubiquitinating enzyme ubiquitin-specific protease 22 (USP22), a component of the deubiquitinating module (DUBm) of the SAGA transcriptional coactivating complex, as a SIRT1-interacting partner. We found that this interaction is highly specific, requires the ZnF-UBP domain of USP22, and is disrupted by the inactivating H363Y mutation within SIRT1. Moreover, we show that USP22 is acetylated on multiple lysine residues and that alteration of a single lysine (K129) within the ZnF-UBP domain is sufficient to alter interaction of the DUBm with the core SAGA complex. Furthermore, USP22-mediated recruitment of SIRT1 activity promotes the deacetylation of individual SAGA complex components. Our results indicate an important role of SIRT1-mediated deacetylation in regulating the formation of DUBm subcomplexes within the larger SAGA complex.

  9. A novel acetylation cycle of transcription co-activator Yes-associated protein that is downstream of Hippo pathway is triggered in response to SN2 alkylating agents.

    Science.gov (United States)

    Hata, Shoji; Hirayama, Jun; Kajiho, Hiroaki; Nakagawa, Kentaro; Hata, Yutaka; Katada, Toshiaki; Furutani-Seiki, Makoto; Nishina, Hiroshi

    2012-06-22

    Yes-associated protein (YAP) is a transcriptional co-activator that acts downstream of the Hippo signaling pathway and regulates multiple cellular processes. Although cytoplasmic retention of YAP is known to be mediated by Hippo pathway-dependent phosphorylation, post-translational modifications that regulate YAP in the nucleus remain unclear. Here we report the discovery of a novel cycle of acetylation/deacetylation of nuclear YAP induced in response to S(N)2 alkylating agents. We show that after treatment of cells with the S(N)2 alkylating agent methyl methanesulfonate, YAP phosphorylation mediated by the Hippo pathway is markedly reduced, leading to nuclear translocation of YAP and its acetylation. This YAP acetylation occurs on specific and highly conserved C-terminal lysine residues and is mediated by the nuclear acetyltransferases CBP (CREB binding protein) and p300. Conversely, the nuclear deacetylase SIRT1 is responsible for YAP deacetylation. Intriguingly, we found that YAP acetylation is induced specifically by S(N)2 alkylating agents and not by other DNA-damaging stimuli. These results identify a novel YAP acetylation cycle that occurs in the nucleus downstream of the Hippo pathway. Intriguingly, our findings also indicate that YAP acetylation is involved in responses to a specific type of DNA damage.

  10. A Novel Acetylation Cycle of Transcription Co-activator Yes-associated Protein That Is Downstream of Hippo Pathway Is Triggered in Response to SN2 Alkylating Agents*

    Science.gov (United States)

    Hata, Shoji; Hirayama, Jun; Kajiho, Hiroaki; Nakagawa, Kentaro; Hata, Yutaka; Katada, Toshiaki; Furutani-Seiki, Makoto; Nishina, Hiroshi

    2012-01-01

    Yes-associated protein (YAP) is a transcriptional co-activator that acts downstream of the Hippo signaling pathway and regulates multiple cellular processes. Although cytoplasmic retention of YAP is known to be mediated by Hippo pathway-dependent phosphorylation, post-translational modifications that regulate YAP in the nucleus remain unclear. Here we report the discovery of a novel cycle of acetylation/deacetylation of nuclear YAP induced in response to SN2 alkylating agents. We show that after treatment of cells with the SN2 alkylating agent methyl methanesulfonate, YAP phosphorylation mediated by the Hippo pathway is markedly reduced, leading to nuclear translocation of YAP and its acetylation. This YAP acetylation occurs on specific and highly conserved C-terminal lysine residues and is mediated by the nuclear acetyltransferases CBP (CREB binding protein) and p300. Conversely, the nuclear deacetylase SIRT1 is responsible for YAP deacetylation. Intriguingly, we found that YAP acetylation is induced specifically by SN2 alkylating agents and not by other DNA-damaging stimuli. These results identify a novel YAP acetylation cycle that occurs in the nucleus downstream of the Hippo pathway. Intriguingly, our findings also indicate that YAP acetylation is involved in responses to a specific type of DNA damage. PMID:22544757

  11. Natural derivatives of curcumin attenuate the Wnt/β-catenin pathway through down-regulation of the transcriptional coactivator p300

    International Nuclear Information System (INIS)

    Ryu, Min-Jung; Cho, Munju; Song, Jie-Young; Yun, Yeon-Sook; Choi, Il-Whan; Kim, Dong-Eun; Park, Byeoung-Soo; Oh, Sangtaek

    2008-01-01

    Curcumin, a component of turmeric (Curcuma longa), has been reported to suppress β-catenin response transcription (CRT), which is aberrantly activated in colorectal cancer. However, the effects of its natural analogs (demethoxycurcumin [DMC] and bisdemethoxycurcumin [BDMC]) and metabolite (tetrahydrocurcumin [THC]) on the Wnt/β-catenin pathway have not been investigated. Here, we show that DMC and BDMC suppressed CRT that was activated by Wnt3a conditioned-medium (Wnt3a-CM) without altering the level of intracellular β-catenin, and inhibited the growth of various colon cancer cells, with comparable potency to curcumin. Additionally, DMC and BDMC down-regulated p300, which is a positive regulator of the Wnt/β-catenin pathway. Notably, THC also inhibited CRT and cell proliferation, but to a much lesser degree than curcumin, DMC, or BDMC, indicating that the conjugated bonds in the central seven-carbon chain of curcuminoids are essential for the inhibition of Wnt/β-catenin pathway and the anti-proliferative activity of curcuminoids. Thus, our findings suggest that curcumin derivatives inhibit the Wnt/β-catenin pathway by decreasing the amount of the transcriptional coactivator p300.

  12. Interactome analysis of transcriptional coactivator multiprotein bridging factor 1 unveils a yeast AP-1-like transcription factor involved in oxidation tolerance of mycopathogen Beauveria bassiana.

    Science.gov (United States)

    Chu, Xin-Ling; Dong, Wei-Xia; Ding, Jin-Li; Feng, Ming-Guang; Ying, Sheng-Hua

    2018-02-01

    Oxidation tolerance is an important determinant to predict the virulence and biocontrol potential of Beauveria bassiana, a well-known entomopathogenic fungus. As a transcriptional coactivator, multiprotein bridging factor 1 mediates the activity of transcription factor in diverse physiological processes, and its homolog in B. bassiana (BbMBF1) contributes to fungal oxidation tolerance. In this study, the BbMBF1-interactomes under oxidative stress and normal growth condition were deciphered by mass spectrometry integrated with the immunoprecipitation. BbMBF1p factor has a broad interaction with proteins that are involved in various cellular processes, and this interaction is dynamically regulated by oxidative stress. Importantly, a B. bassiana homolog of yeast AP-1-like transcription factor (BbAP-1) was specifically associated with the BbMBF1-interactome under oxidation and significantly contributed to fungal oxidation tolerance. In addition, qPCR analysis revealed that several antioxidant genes are jointly controlled by BbAP-1 and BbMBF1. Conclusively, it is proposed that BbMBF1p protein mediates BbAP-1p factor to transcribe the downstream antioxidant genes in B. bassiana under oxidative stress. This study demonstrates for the first time a proteomic view of the MBF1-interactome in fungi, and presents an initial framework to probe the transcriptional mechanism involved in fungal response to oxidation, which will provide a new strategy to improve the biocontrol efficacy of B. bassiana.

  13. KDM4A Coactivates E2F1 to Regulate the PDK-Dependent Metabolic Switch between Mitochondrial Oxidation and Glycolysis

    Directory of Open Access Journals (Sweden)

    Ling-Yu Wang

    2016-09-01

    Full Text Available The histone lysine demethylase KDM4A/JMJD2A has been implicated in prostate carcinogenesis through its role in transcriptional regulation. Here, we describe KDM4A as a E2F1 coactivator and demonstrate a functional role for the E2F1-KDM4A complex in the control of tumor metabolism. KDM4A associates with E2F1 on target gene promoters and enhances E2F1 chromatin binding and transcriptional activity, thereby modulating the transcriptional profile essential for cancer cell proliferation and survival. The pyruvate dehydrogenase kinases (PDKs PDK1 and PDK3 are direct targets of KDM4A and E2F1 and modulate the switch between glycolytic metabolism and mitochondrial oxidation. Downregulation of KDM4A leads to elevated activity of pyruvate dehydrogenase and mitochondrial oxidation, resulting in excessive accumulation of reactive oxygen species. The altered metabolic phenotypes can be partially rescued by ectopic expression of PDK1 and PDK3, indicating a KDM4A-dependent tumor metabolic regulation via PDK. Our results suggest that KDM4A is a key regulator of tumor metabolism and a potential therapeutic target for prostate cancer.

  14. The Mediator co-activator complex regulates Ty1 retromobility by controlling the balance between Ty1i and Ty1 promoters.

    Science.gov (United States)

    Salinero, Alicia C; Knoll, Elisabeth R; Zhu, Z Iris; Landsman, David; Curcio, M Joan; Morse, Randall H

    2018-02-01

    The Ty1 retrotransposons present in the genome of Saccharomyces cerevisiae belong to the large class of mobile genetic elements that replicate via an RNA intermediary and constitute a significant portion of most eukaryotic genomes. The retromobility of Ty1 is regulated by numerous host factors, including several subunits of the Mediator transcriptional co-activator complex. In spite of its known function in the nucleus, previous studies have implicated Mediator in the regulation of post-translational steps in Ty1 retromobility. To resolve this paradox, we systematically examined the effects of deleting non-essential Mediator subunits on the frequency of Ty1 retromobility and levels of retromobility intermediates. Our findings reveal that loss of distinct Mediator subunits alters Ty1 retromobility positively or negatively over a >10,000-fold range by regulating the ratio of an internal transcript, Ty1i, to the genomic Ty1 transcript. Ty1i RNA encodes a dominant negative inhibitor of Ty1 retromobility that blocks virus-like particle maturation and cDNA synthesis. These results resolve the conundrum of Mediator exerting sweeping control of Ty1 retromobility with only minor effects on the levels of Ty1 genomic RNA and the capsid protein, Gag. Since the majority of characterized intrinsic and extrinsic regulators of Ty1 retromobility do not appear to effect genomic Ty1 RNA levels, Mediator could play a central role in integrating signals that influence Ty1i expression to modulate retromobility.

  15. Identification of transcription coactivator OCA-B-dependent genes involved in antigen-dependent B cell differentiation by cDNA array analyses.

    Science.gov (United States)

    Kim, Unkyu; Siegel, Rachael; Ren, Xiaodi; Gunther, Cary S; Gaasterland, Terry; Roeder, Robert G

    2003-07-22

    The tissue-specific transcriptional coactivator OCA-B is required for antigen-dependent B cell differentiation events, including germinal center formation. However, the identity of OCA-B target genes involved in this process is unknown. This study has used large-scale cDNA arrays to monitor changes in gene expression patterns that accompany mature B cell differentiation. B cell receptor ligation alone induces many genes involved in B cell expansion, whereas B cell receptor and helper T cell costimulation induce genes associated with B cell effector function. OCA-B expression is induced by both B cell receptor ligation alone and helper T cell costimulation, suggesting that OCA-B is involved in B cell expansion as well as B cell function. Accordingly, several genes involved in cell proliferation and signaling, such as Lck, Kcnn4, Cdc37, cyclin D3, B4galt1, and Ms4a11, have been identified as OCA-B-dependent genes. Further studies on the roles played by these genes in B cells will contribute to an understanding of B cell differentiation.

  16. S phase activation of the histone H2B promoter by OCA-S, a coactivator complex that contains GAPDH as a key component.

    Science.gov (United States)

    Zheng, Lei; Roeder, Robert G; Luo, Yan

    2003-07-25

    We have isolated and functionally characterized a multicomponent Oct-1 coactivator, OCA-S which is essential for S phase-dependent histone H2B transcription. The p38 component of OCA-S binds directly to Oct-1, exhibits potent transactivation potential, is selectively recruited to the H2B promoter in S phase, and is essential for S phase-specific H2B transcription in vivo and in vitro. Surprisingly, p38 represents a nuclear form of glyceraldehyde-3-phosphate dehydrogenase, and binding to Oct-1, as well as OCA-S function, is stimulated by NAD(+) but inhibited by NADH. OCA-S also interacts with NPAT, a cyclin E/cdk2 substrate that is broadly involved in histone gene transcription. These studies thus link the H2B transcriptional machinery to cell cycle regulators, and possibly to cellular metabolic state (redox status), and set the stage for studies of the underlying mechanisms and the basis for coordinated histone gene expression and coupling to DNA replication.

  17. Interaction of the B cell-specific transcriptional coactivator OCA-B and galectin-1 and a possible role in regulating BCR-mediated B cell proliferation.

    Science.gov (United States)

    Yu, Xin; Siegel, Rachael; Roeder, Robert G

    2006-06-02

    OCA-B is a B cell-specific transcriptional coactivator for OCT factors during the activation of immunoglobulin genes. In addition, OCA-B is crucial for B cell activation and germinal center formation. However, the molecular mechanisms for OCA-B function in these processes are not clear. Our previous studies documented two OCA-B isoforms and suggested a novel mechanism for the function of the myristoylated, membrane-bound form of OCA-B/p35 as a signaling molecule. Here, we report the identification of galectin-1, and related galectins, as a novel OCA-B-interacting protein. The interaction of OCA-B and galectin-1 can be detected both in vivo and in vitro. The galectin-1 binding domain in OCA-B has been localized to the N terminus of OCA-B. In B cells lacking OCA-B expression, increased galectin-1 expression, secretion, and cell surface association are observed. Consistent with these observations, and a reported inhibitory interaction of galectin-1 with CD45, the phosphatase activity of CD45 is reduced modestly, but significantly, in OCA-B-deficient B cells. Finally, galectin-1 is shown to negatively regulate B cell proliferation and tyrosine phosphorylation upon BCR stimulation. Together, these results raise the possibility that OCA-B may regulate BCR signaling through an association with galectin-1.

  18. Luminescence properties of Ce{sup 3+} and Tb{sup 3+} co-activated ZnAl{sub 2}O{sub 4} phosphor

    Energy Technology Data Exchange (ETDEWEB)

    Tshabalala, K.G. [Department of Physics, University of the Free State, Bloemfontein, ZA 9300 (South Africa); Cho, S.-H.; Park, J.-K. [Nano-Materials Center, Korea Institute of Science and Technology, Cheongryang, Seoul 130-650 (Korea, Republic of); Pitale, Shreyas S.; Nagpure, I.M.; Kroon, R.E.; Swart, H.C. [Department of Physics, University of the Free State, Bloemfontein, ZA 9300 (South Africa); Ntwaeaborwa, O.M., E-mail: ntwaeab@ufs.ac.za [Department of Physics, University of the Free State, Bloemfontein, ZA 9300 (South Africa)

    2012-05-15

    In this study, a solution combustion method was used to prepare green emitting Ce{sup 3+}-Tb{sup 3+} co-activated ZnAl{sub 2}O{sub 4} phosphor. The samples were annealed at 700 Degree-Sign C in air or hydrogen atmosphere to improve their crystallinity and optical properties. X-ray diffraction study confirmed that both as-prepared and post-preparation annealed samples crystallized in the well known cubic spinel structure of ZnAl{sub 2}O{sub 4}. An agglomeration of irregular platelet-like particles whose surfaces were encrusted with smaller spheroidal particles was confirmed by scanning electron microscopy (SEM). The fluorescence data collected from the annealed samples with different concentrations of Ce{sup 3+} and Tb{sup 3+} show the enhanced green emission at 543 nm associated with {sup 5}D{sub 4}{yields}{sup 7}F{sub 5} transitions of Tb{sup 3+}. The enhancement was attributed to energy transfer from Ce{sup 3+} to Tb{sup 3+}. Possible mechanism of energy transfer via a down conversion process is discussed. Furthermore, cathodoluminescence (CL) intensity degradation of this phosphor was also investigated and the degradation data suggest that the material was chemically stable and the CL intensity was also stable after 10 h of irradiation by a beam of high energy electrons.

  19. Correspondent Functional Topography of the Human Left Inferior Parietal Lobule at Rest and Under Task Revealed Using Resting-State fMRI and Coactivation Based Parcellation.

    Science.gov (United States)

    Wang, Jiaojian; Xie, Sangma; Guo, Xin; Becker, Benjamin; Fox, Peter T; Eickhoff, Simon B; Jiang, Tianzi

    2017-03-01

    The human left inferior parietal lobule (LIPL) plays a pivotal role in many cognitive functions and is an important node in the default mode network (DMN). Although many previous studies have proposed different parcellation schemes for the LIPL, the detailed functional organization of the LIPL and the exact correspondence between the DMN and LIPL subregions remain unclear. Mounting evidence indicates that spontaneous fluctuations in the brain are strongly associated with cognitive performance at the behavioral level. However, whether a consistent functional topographic organization of the LIPL during rest and under task can be revealed remains unknown. Here, they used resting-state functional connectivity (RSFC) and task-related coactivation patterns separately to parcellate the LIPL and identified seven subregions. Four subregions were located in the supramarginal gyrus (SMG) and three subregions were located in the angular gyrus (AG). The subregion-specific networks and functional characterization revealed that the four anterior subregions were found to be primarily involved in sensorimotor processing, movement imagination and inhibitory control, audition perception and speech processing, and social cognition, whereas the three posterior subregions were mainly involved in episodic memory, semantic processing, and spatial cognition. The results revealed a detailed functional organization of the LIPL and suggested that the LIPL is a functionally heterogeneous area. In addition, the present study demonstrated that the functional architecture of the LIPL during rest corresponds with that found in task processing. Hum Brain Mapp 38:1659-1675, 2017. © 2017 Wiley Periodicals, Inc. © 2017 Wiley Periodicals, Inc.

  20. Stimulation of StAR expression by cAMP is controlled by inhibition of highly inducible SIK1 via CRTC2, a co-activator of CREB.

    Science.gov (United States)

    Lee, Jinwoo; Tong, Tiegang; Takemori, Hiroshi; Jefcoate, Colin

    2015-06-15

    In mouse steroidogenic cells the activation of cholesterol metabolism is mediated by steroidogenic acute regulatory protein (StAR). Here, we visualized a coordinated regulation of StAR transcription, splicing and post-transcriptional processing, which are synchronized by salt inducible kinase (SIK1) and CREB-regulated transcription coactivator (CRTC2). To detect primary RNA (pRNA), spliced primary RNA (Sp-RNA) and mRNA in single cells, we generated probe sets by using fluorescence in situ hybridization (FISH). These methods allowed us to address the nature of StAR gene expression and to visualize protein-nucleic acid interactions through direct detection. We show that SIK1 represses StAR expression in Y1 adrenal and MA10 testis cells through inhibition of processing mediated by CRTC2. Digital image analysis matches qPCR analyses of the total cell culture. Evidence is presented for spatially separate accumulation of StAR pRNA and Sp-RNA at the gene loci in the nucleus. These findings establish that cAMP, SIK and CRTC mediate StAR expression through activation of individual StAR gene loci. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

  1. Coactivator-associated arginine methyltransferase 1 enhances transcriptional activity of the human T-cell lymphotropic virus type 1 long terminal repeat through direct interaction with Tax.

    Science.gov (United States)

    Jeong, Soo-Jin; Lu, Hanxin; Cho, Won-Kyung; Park, Hyeon Ung; Pise-Masison, Cynthia; Brady, John N

    2006-10-01

    In this study, we demonstrate that the coactivator-associated arginine methyltransferase 1 (CARM1), which methylates histone H3 and other proteins such as p300/CBP, is positively involved in the regulation of Tax transactivation. First, transfection studies demonstrated that overexpression of CARM1 wild-type protein resulted in increased Tax transactivation of the human T-cell lymphotropic virus type 1 (HTLV-1) long terminal repeat (LTR). In contrast, transfection of a catalytically inactive CARM1 methyltransferase mutant did not enhance Tax transactivation. CARM1 facilitated Tax transactivation of the CREB-dependent cellular GEM promoter. A direct physical interaction between HTLV-1 Tax and CARM1 was demonstrated using in vitro glutathione S-transferase-Tax binding assays, in vivo coimmunoprecipitation, and confocal microscopy experiments. Finally, chromatin immunoprecipitation analysis of the activated HTLV-1 LTR promoter showed the association of CARM1 and methylated histone H3 with the template DNA. In vitro, Tax facilitates the binding of CARM1 to the transcription complex. Together, our data provide evidence that CARM1 enhances Tax transactivation of the HTLV-1 LTR through a direct interaction between CARM1 and Tax and this binding promotes methylation of histone H3 (R2, R17, and R26).

  2. Phylogeny and origin of 82 zygomycetes from all 54 genera of the Mucorales and Mortierellales based on combined analysis of actin and translation elongation factor EF-1alpha genes.

    Science.gov (United States)

    Voigt, K; Wöstemeyer, J

    2001-05-30

    True fungi (Eumycota) are heterotrophic eukaryotic microorganisms encompassing ascomycetes, basidiomycetes, chytridiomycetes and zygomycetes. The natural systematics of the latter group, Zygomycota, are very poorly understood due to the lack of distinguishing morphological characters. We have determined sequences for the nuclear-encoded genes actin (act) from 82 zygomycetes representing all 54 currently recognized genera from the two zygomycetous orders Mucorales and Mortierellales. We also determined sequences for translation elongation factor EF-1alpha (tef) from 16 zygomycetes (total of 96,837 bp). Phylogenetic analysis in the context of available sequence data (total 2,062 nucleotide positions per species) revealed that current classification schemes for the mucoralean fungi are highly unnatural at the family and, to a large extent, at the genus level. The data clearly indicate a deep, ancient and distinct dichotomy of the orders Mucorales and Mortierellales, which are recognized only in some zygomycete systems. Yet at the same time the data show that two genera - Umbelopsis and Micromucor - previously placed within the Mortierellales on the basis of their weakly developed columella (a morphological structure of the sporangiophore well-developed within all Mucorales) are in fact members of the Mucorales. Phylogenetic analyses of the encoded amino acid sequences in the context of homologues from eukaryotes and archaebacterial outgroups indicate that the Eumycota studied here are a natural group but provide little or no support for the monophyly of either zygomycetes, ascomycetes or basidiomycetes. The data clearly indicate that a complete revision of zygomycete natural systematics is necessary.

  3. Autophagy activation, not peroxisome proliferator-activated receptor γ coactivator 1α, may mediate exercise-induced improvements in glucose handling during diet-induced obesity.

    Science.gov (United States)

    Rosa-Caldwell, Megan E; Brown, Jacob L; Lee, David E; Blackwell, Thomas A; Turner, Kyle W; Brown, Lemuel A; Perry, Richard A; Haynie, Wesley S; Washington, Tyrone A; Greene, Nicholas P

    2017-09-01

    What is the central question of this study? What are the individual and combined effects of muscle-specific peroxisome proliferator-activated receptor γ coactivator 1α (PGC-1α) overexpression and physical activity during high-fat feeding on glucose and exercise tolerance? What is the main finding and its importance? Our main finding is that muscle-specific PGC-1α overexpression provides no protection against lipid-overload pathologies nor does it enhance exercise adaptations. Instead, physical activity, regardless of PGC-1α content, protects against high-fat diet-induced detriments. Activation of muscle autophagy was correlated with exercise protection, suggesting that autophagy might be a mediating factor for exercise-induced protection from lipid overload. The prevalence of glucose intolerance is alarmingly high. Efforts to promote mitochondrial biogenesis through peroxisome proliferator-activated receptor γ coactivator 1α (PGC-1α) to mitigate glucose intolerance have been controversial. However, physical activity remains a primary means to alleviate the condition. The aim of this study was to determine the combined effects of muscle-specific overexpression of PGC-1α and physical activity on glucose handling during diet-induced obesity. Wild-type (WT, ∼20) and PGC-1α muscle transgenic (MCK-PGC-1α, ∼20) mice were given a Western diet (WD) at 8 weeks age and allowed to consume food ab libitum throughout the study. At 12 weeks of age, all animals were divided into sedentary (SED) or voluntary wheel running (VWR) interventions. At 7, 11 and 15 weeks of age, animals underwent glucose tolerance tests (GTT) and graded exercise tests (GXT). At 16 weeks of age, tissues were collected. At 11 weeks, the MCK-PGC-1α animals had 50% greater glucose tolerance integrated area under the curve compared with WT. However, at 15 weeks, SED animals also had greater GTT integrated area under the curve compared with VWR, regardless of genotype; furthermore, SED

  4. Deletion of the transcriptional coactivator PGC1α in skeletal muscles is associated with reduced expression of genes related to oxidative muscle function

    International Nuclear Information System (INIS)

    Hatazawa, Yukino; Minami, Kimiko; Yoshimura, Ryoji; Onishi, Takumi; Manio, Mark Christian; Inoue, Kazuo; Sawada, Naoki; Suzuki, Osamu; Miura, Shinji; Kamei, Yasutomi

    2016-01-01

    The expression of the transcriptional coactivator PGC1α is increased in skeletal muscles during exercise. Previously, we showed that increased PGC1α leads to prolonged exercise performance (the duration for which running can be continued) and, at the same time, increases the expression of branched-chain amino acid (BCAA) metabolism-related enzymes and genes that are involved in supplying substrates for the TCA cycle. We recently created mice with PGC1α knockout specifically in the skeletal muscles (PGC1α KO mice), which show decreased mitochondrial content. In this study, global gene expression (microarray) analysis was performed in the skeletal muscles of PGC1α KO mice compared with that of wild-type control mice. As a result, decreased expression of genes involved in the TCA cycle, oxidative phosphorylation, and BCAA metabolism were observed. Compared with previously obtained microarray data on PGC1α-overexpressing transgenic mice, each gene showed the completely opposite direction of expression change. Bioinformatic analysis of the promoter region of genes with decreased expression in PGC1α KO mice predicted the involvement of several transcription factors, including a nuclear receptor, ERR, in their regulation. As PGC1α KO microarray data in this study show opposing findings to the PGC1α transgenic data, a loss-of-function experiment, as well as a gain-of-function experiment, revealed PGC1α’s function in the oxidative energy metabolism of skeletal muscles. - Highlights: • Microarray analysis was performed in the skeletal muscle of PGC1α KO mice. • Expression of genes in the oxidative energy metabolism was decreased. • Bioinformatic analysis of promoter region of the genes predicted involvement of ERR. • PGC1α KO microarray data in this study show the mirror image of transgenic data.

  5. Antidepressant Imipramine Protects Bupivacaine-Induced Neurotoxicity in Dorsal Root Ganglion Neurons Through Coactivation of TrkA and TrkB.

    Science.gov (United States)

    Guo, Jianrong; Wang, Huan; Tao, Qiang; Sun, Shiyu; Liu, Li; Zhang, Jianping; Yang, Dawei

    2017-11-01

    In our work, we used an in vitro culture model to investigate whether antidepressant imipramine (Ip) may protect bupivacaine (Bv)-induced neurotoxicity in mouse dorsal root ganglion (DRG). Adult mouse DRG was treated with 5 mM Bv in vitro to induce neurotoxicity. DRG was then pre-treated with Ip, prior to Bv, to examine its effects on protecting Bv-induced DRG apoptosis and neurite degeneration. Ip-induced dynamic changes in Trk receptors, including TrkA/B/C and phosphor (p-)TrkA/B/C, were examined by qPCR and Western blot. TrkA and TrkB were inhibited by siRNAs to further investigate their functional role in Ip- and Bv-treated DRG. Ip protected Bv-induced apoptosis and neurite loss in DRG. Ip did not alter TrkA/B/C expressions, whereas significantly augmented protein productions of p-TrkA and p-TrkB, but not p-TrkC. SiRNA-mediated TrkA or TrkB downregulation inhibited Trk receptors, and reduced p-TrkA and p-TrkB in DRG. TrkA or TrkB downregulation alone had no effect on Ip-induced protection in Bv-injured DRG. However, co-inhibition of TrkA and TrkB significantly ameliorated the protective effect of Ip on Bv-induced apoptosis and neurite loss in DRG. Imipramine protected bupivacaine-induced neurotoxicity in DRG, likely via the co-activation of TrkA and TrkB signaling pathways. J. Cell. Biochem. 118: 3960-3967, 2017. © 2017 Wiley Periodicals, Inc. © 2017 Wiley Periodicals, Inc.

  6. XX ovarian dysgenesis is caused by a PSMC3IP/HOP2 mutation that abolishes coactivation of estrogen-driven transcription.

    Science.gov (United States)

    Zangen, David; Kaufman, Yotam; Zeligson, Sharon; Perlberg, Shira; Fridman, Hila; Kanaan, Moein; Abdulhadi-Atwan, Maha; Abu Libdeh, Abdulsalam; Gussow, Ayal; Kisslov, Irit; Carmel, Liran; Renbaum, Paul; Levy-Lahad, Ephrat

    2011-10-07

    XX female gonadal dysgenesis (XX-GD) is a rare, genetically heterogeneous disorder characterized by lack of spontaneous pubertal development, primary amenorrhea, uterine hypoplasia, and hypergonadotropic hypogonadism as a result of streak gonads. Most cases are unexplained but thought to be autosomal recessive. We elucidated the genetic basis of XX-GD in a highly consanguineous Palestinian family by using homozygosity mapping and candidate-gene and whole-exome sequencing. Affected females were homozygous for a 3 bp deletion (NM_016556.2, c.600_602del) in the PSMC3IP gene, leading to deletion of a glutamic acid residue (p.Glu201del) in the highly conserved C-terminal acidic domain. Proteasome 26S subunit, ATPase, 3-Interacting Protein (PSMC3IP)/Tat Binding Protein Interacting Protein (TBPIP) is a nuclear, tissue-specific protein with multiple functions. It is critical for meiotic recombination as indicated by the known role of its yeast ortholog, Hop2. Through the C terminus (not present in yeast), PSMC3IP also coactivates ligand-driven transcription mediated by estrogen, androgen, glucocorticoid, progesterone, and thyroid nuclear receptors. In cell lines, the p.Glu201del mutation abolished PSMC3IP activation of estrogen-driven transcription. Impaired estrogenic signaling can lead to ovarian dysgenesis both by affecting the size of the follicular pool created during fetal development and by failing to counteract follicular atresia during puberty. PSMC3IP joins previous genes known to be mutated in XX-GD, the FSH receptor, and BMP15, highlighting the importance of hormonal signaling in ovarian development and maintenance and suggesting a common pathway perturbed in isolated XX-GD. By analogy to other XX-GD genes, PSMC3IP is also a candidate gene for premature ovarian failure, and its role in folliculogenesis should be further investigated. Copyright © 2011 The American Society of Human Genetics. Published by Elsevier Inc. All rights reserved.

  7. Baicalein suppresses the androgen receptor (AR)-mediated prostate cancer progression via inhibiting the AR N-C dimerization and AR-coactivators interaction.

    Science.gov (United States)

    Xu, Defeng; Chen, Qiulu; Liu, Yalin; Wen, Xingqiao

    2017-12-01

    Androgen receptor (AR) plays a critical role in prostate cancer (PCa) development and progression. Androgen deprivation therapy with antiandrogens to reduce androgen biosynthesis or prevent androgens from binding to AR are widely used to suppress AR-mediated PCa growth. However, most of ADT may eventually fail with development of the castration resistance after 12-24 months. Here we found that a natural product baicalein can effectively suppress the PCa progression via targeting the androgen-induced AR transactivation with little effect to AR protein expression. PCa cells including LNCaP, CWR22Rv1, C4-2, PC-3, and DU145, were treated with baicalein and luciferase assay was used to evaluate their effect on the AR transactivation. Cell growth and IC 50 were determined by MTT assay after 48 hrs treatment. RT-PCR was used to evaluate the mRNA levels of AR target genes including PSA, TMPRSS2, and TMEPA1. Western blot was used to determine AR and PSA protein expression. The natural product of baicalein can selectively inhibit AR transactivation with little effect on the other nuclear receptors, including ERα, and GR. At a low concentration, 2.5 μM of baicalein effectively suppresses the growth of AR-positive PCa cells, and has little effect on AR-negative PCa cells. Mechanism dissection suggest that baicalein can suppress AR target genes (PSA, TMPRSS2, and TMEPA1) expression in both androgen responsive LNCaP cells and castration resistant CWR22Rv1 cells, that may involve the inhibiting the AR N/C dimerization and AR-coactivators interaction. Baicalein may be developed as an effective anti-AR therapy via its ability to inhibit AR transactivation and AR-mediated PCa cell growth.

  8. Reservoir inflow forecasting with a modified coactive neuro-fuzzy inference system: a case study for a semi-arid region

    Science.gov (United States)

    Allawi, Mohammed Falah; Jaafar, Othman; Mohamad Hamzah, Firdaus; Mohd, Nuruol Syuhadaa; Deo, Ravinesh C.; El-Shafie, Ahmed

    2017-10-01

    Existing forecast models applied for reservoir inflow forecasting encounter several drawbacks, due to the difficulty of the underlying mathematical procedures being to cope with and to mimic the naturalization and stochasticity of the inflow data patterns. In this study, appropriate adjustments to the conventional coactive neuro-fuzzy inference system (CANFIS) method are proposed to improve the mathematical procedure, thus enabling a better detection of the high nonlinearity patterns found in the reservoir inflow training data. This modification includes the updating of the back propagation algorithm, leading to a consequent update of the membership rules and the induction of the centre-weighted set rather than the global weighted set used in feature extraction. The modification also aids in constructing an integrated model that is able to not only detect the nonlinearity in the training data but also the wide range of features within the training data records used to simulate the forecasting model. To demonstrate the model's efficacy, the proposed CANFIS method has been applied to forecast monthly inflow data at Aswan High Dam (AHD), located in southern Egypt. Comparative analyses of the forecasting skill of the modified CANFIS and the conventional ANFIS model are carried out with statistical score indicators to assess the reliability of the developed method. The statistical metrics support the better performance of the developed CANFIS model, which significantly outperforms the ANFIS model to attain a low relative error value (23%), mean absolute error (1.4 BCM month-1), root mean square error (1.14 BCM month-1), and a relative large coefficient of determination (0.94). The present study ascertains the better utility of the modified CANFIS model in respect to the traditional ANFIS model applied in reservoir inflow forecasting for a semi-arid region.

  9. Interaction of the transactivation domain of B-Myb with the TAZ2 domain of the coactivator p300: molecular features and properties of the complex.

    Directory of Open Access Journals (Sweden)

    Ojore Oka

    Full Text Available The transcription factor B-Myb is a key regulator of the cell cycle in vertebrates, with activation of transcription involving the recognition of specific DNA target sites and the recruitment of functional partner proteins, including the coactivators p300 and CBP. Here we report the results of detailed studies of the interaction between the transactivation domain of B-Myb (B-Myb TAD and the TAZ2 domain of p300. The B-Myb TAD was characterized using circular dichroism, fluorescence and NMR spectroscopy, which revealed that the isolated domain exists as a random coil polypeptide. Pull-down and spectroscopic experiments clearly showed that the B-Myb TAD binds to p300 TAZ2 to form a moderately tight (K(d ~1.0-10 µM complex, which results in at least partial folding of the B-Myb TAD. Significant changes in NMR spectra of p300 TAZ2 suggest that the B-Myb TAD binds to a relatively large patch on the surface of the domain (~1200 Å(2. The apparent B-Myb TAD binding site on p300 TAZ2 shows striking similarity to the surface of CBP TAZ2 involved in binding to the transactivation domain of the transcription factor signal transducer and activator of transcription 1 (STAT1, which suggests that the structure of the B-Myb TAD-p300 TAZ2 complex may share many features with that reported for STAT1 TAD-p300 TAZ2.

  10. Antisense-mediated isoform switching of steroid receptor coactivator-1 in the central nucleus of the amygdala of the mouse brain

    Directory of Open Access Journals (Sweden)

    Zalachoras Ioannis

    2013-01-01

    Full Text Available Abstract Background Antisense oligonucleotide (AON-mediated exon skipping is a powerful tool to manipulate gene expression. In the present study we investigated the potential of exon skipping by local injection in the central nucleus of the amygdala (CeA of the mouse brain. As proof of principle we targeted the splicing of steroid receptor coactivator-1 (SRC-1, a protein involved in nuclear receptor function. This nuclear receptor coregulator exists in two splice variants (SRC-1a and SRC-1e which display differential distribution and opposing activities in the brain, and whose mRNAs differ in a single SRC-1e specific exon. Methods For proof of principle of feasibility, we used immunofluorescent stainings to study uptake by different cell types, translocation to the nucleus and potential immunostimulatory effects at different time points after a local injection in the CeA of the mouse brain of a control AON targeting human dystrophin with no targets in the murine brain. To evaluate efficacy we designed an AON targeting the SRC-1e-specific exon and with qPCR analysis we measured the expression ratio of the two splice variants. Results We found that AONs were taken up by corticotropin releasing hormone expressing neurons and other cells in the CeA, and translocated into the cell nucleus. Immune responses after AON injection were comparable to those after sterile saline injection. A successful shift of the naturally occurring SRC-1a:SRC-1e expression ratio in favor of SRC-1a was observed, without changes in total SRC-1 expression. Conclusions We provide a proof of concept for local neuropharmacological use of exon skipping by manipulating the expression ratio of the two splice variants of SRC-1, which may be used to study nuclear receptor function in specific brain circuits. We established that exon skipping after local injection in the brain is a versatile and useful tool for the manipulation of splice variants for numerous genes that are relevant

  11. WD40 domain of Apc1 is critical for the coactivator-induced allosteric transition that stimulates APC/C catalytic activity.

    Science.gov (United States)

    Li, Qiuhong; Chang, Leifu; Aibara, Shintaro; Yang, Jing; Zhang, Ziguo; Barford, David

    2016-09-20

    The anaphase-promoting complex/cyclosome (APC/C) is a large multimeric cullin-RING E3 ubiquitin ligase that orchestrates cell-cycle progression by targeting cell-cycle regulatory proteins for destruction via the ubiquitin proteasome system. The APC/C assembly comprises two scaffolding subcomplexes: the platform and the TPR lobe that together coordinate the juxtaposition of the catalytic and substrate-recognition modules. The platform comprises APC/C subunits Apc1, Apc4, Apc5, and Apc15. Although the role of Apc1 as an APC/C scaffolding subunit has been characterized, its specific functions in contributing toward APC/C catalytic activity are not fully understood. Here, we report the crystal structure of the N-terminal domain of human Apc1 (Apc1N) determined at 2.2-Å resolution and provide an atomic-resolution description of the architecture of its WD40 (WD40 repeat) domain (Apc1(WD40)). To understand how Apc1(WD40) contributes to APC/C activity, a mutant form of the APC/C with Apc1(WD40) deleted was generated and evaluated biochemically and structurally. We found that the deletion of Apc1(WD40) abolished the UbcH10-dependent ubiquitination of APC/C substrates without impairing the Ube2S-dependent ubiquitin chain elongation activity. A cryo-EM structure of an APC/C-Cdh1 complex with Apc1(WD40) deleted showed that the mutant APC/C is locked into an inactive conformation in which the UbcH10-binding site of the catalytic module is inaccessible. Additionally, an EM density for Apc15 is not visible. Our data show that Apc1(WD40) is required to mediate the coactivator-induced conformational change of the APC/C that is responsible for stimulating APC/C catalytic activity by promoting UbcH10 binding. In contrast, Ube2S activity toward APC/C substrates is not dependent on the initiation-competent conformation of the APC/C.

  12. Subunits of ADA-two-A-containing (ATAC) or Spt-Ada-Gcn5-acetyltrasferase (SAGA) Coactivator Complexes Enhance the Acetyltransferase Activity of GCN5.

    Science.gov (United States)

    Riss, Anne; Scheer, Elisabeth; Joint, Mathilde; Trowitzsch, Simon; Berger, Imre; Tora, László

    2015-11-27

    Histone acetyl transferases (HATs) play a crucial role in eukaryotes by regulating chromatin architecture and locus specific transcription. GCN5 (KAT2A) is a member of the GNAT (Gcn5-related N-acetyltransferase) family of HATs. In metazoans this enzyme is found in two functionally distinct coactivator complexes, SAGA (Spt Ada Gcn5 acetyltransferase) and ATAC (Ada Two A-containing). These two multiprotein complexes comprise complex-specific and shared subunits, which are organized in functional modules. The HAT module of ATAC is composed of GCN5, ADA2a, ADA3, and SGF29, whereas in the SAGA HAT module ADA2b is present instead of ADA2a. To better understand how the activity of human (h) hGCN5 is regulated in the two related, but different, HAT complexes we carried out in vitro HAT assays. We compared the activity of hGCN5 alone with its activity when it was part of purified recombinant hATAC or hSAGA HAT modules or endogenous hATAC or hSAGA complexes using histone tail peptides and full-length histones as substrates. We demonstrated that the subunit environment of the HAT complexes into which GCN5 incorporates determines the enhancement of GCN5 activity. On histone peptides we show that all the tested GCN5-containing complexes acetylate mainly histone H3K14. Our results suggest a stronger influence of ADA2b as compared with ADA2a on the activity of GCN5. However, the lysine acetylation specificity of GCN5 on histone tails or full-length histones was not changed when incorporated in the HAT modules of ATAC or SAGA complexes. Our results thus demonstrate that the catalytic activity of GCN5 is stimulated by subunits of the ADA2a- or ADA2b-containing HAT modules and is further increased by incorporation of the distinct HAT modules in the ATAC or SAGA holo-complexes. © 2015 by The American Society for Biochemistry and Molecular Biology, Inc.

  13. Lesion Size Is Exacerbated in Hypoxic Rats Whereas Hypoxia-Inducible Factor-1 Alpha and Vascular Endothelial Growth Factor Increase in Injured Normoxic Rats: A Prospective Cohort Study of Secondary Hypoxia in Focal Traumatic Brain Injury.

    Science.gov (United States)

    Thelin, Eric Peter; Frostell, Arvid; Mulder, Jan; Mitsios, Nicholas; Damberg, Peter; Aski, Sahar Nikkhou; Risling, Mårten; Svensson, Mikael; Morganti-Kossmann, Maria Cristina; Bellander, Bo-Michael

    2016-01-01

    Hypoxia following traumatic brain injury (TBI) is a severe insult shown to exacerbate the pathophysiology, resulting in worse outcome. The aim of this study was to investigate the effects of a hypoxic insult in a focal TBI model by monitoring brain edema, lesion volume, serum biomarker levels, immune cell infiltration, as well as the expression of hypoxia-inducible factor-1 alpha (HIF-1α) and vascular endothelial growth factor (VEGF). Female Sprague-Dawley rats (n = 73, including sham and naive) were used. The rats were intubated and mechanically ventilated. A controlled cortical impact device created a 3-mm deep lesion in the right parietal hemisphere. Post-injury, rats inhaled either normoxic (22% O2) or hypoxic (11% O2) mixtures for 30 min. The rats were sacrificed at 1, 3, 7, 14, and 28 days post-injury. Serum was collected for S100B measurements using ELISA. Ex vivo magnetic resonance imaging (MRI) was performed to determine lesion size and edema volume. Immunofluorescence was employed to analyze neuronal death, changes in cerebral macrophage- and neutrophil infiltration, microglia proliferation, apoptosis, complement activation (C5b9), IgG extravasation, HIF-1α, and VEGF. The hypoxic group had significantly increased blood levels of lactate and decreased pO2 (p hypoxic animals (p hypoxic group at 1 day after trauma (p = 0.0868). No differences were observed between the groups in cytotoxic and vascular edema, IgG extravasation, neutrophils and macrophage aggregation, microglia proliferation, or C5b-9 expression. Hypoxia following focal TBI exacerbated the lesion size and neuronal loss. Moreover, there was a tendency to higher levels of S100B in the hypoxic group early after injury, indicating a potential validity as a biomarker of injury severity. In the normoxic group, the expression of HIF-1α and VEGF was found elevated, possibly indicative of neuro-protective responses occurring in this less severely injured group. Further studies are

  14. Synthesis of tritiated 1-alpha-methadol and 1-alpha-acetylmethadol

    Energy Technology Data Exchange (ETDEWEB)

    Thang, D.C.; Nam, N.H.; Pontikis, R. (Institut National de la Sante et de la Recherche Medicale (INSERM), Hopital Fernand Widal, 75 - Paris (France)); Pichat, L. (CEA Centre d' Etudes Nucleaires de Saclay, 91 - Gif-sur-Yvette (France). Service des Molecules Marquees)

    1982-04-01

    dl-Methadone was resolved by crystallization of its ammonium d- ..cap alpha.. -bromocamphor-..pi..-sulfonate salt to give d-methadone. The latter in ethyl acetate solution was reduced with tritium gas to 1-..cap alpha..-methadol /sup 3/H in presence of Adams platinum oxide at normal temperature and pressure. Acetylation of 1-..cap alpha..-carbinol hydrochloride by means of acetyl chloride afforded 1-..cap alpha..-acetylmethadol /sup 3/H, specific activity: 20 Ci/mMole. The positions and extent of tritium labelling were determined by /sup 3/H NMR spectroscopy.

  15. Synthesis of tritiated 1-alpha-methadol and 1-alpha-acetylmethadol

    International Nuclear Information System (INIS)

    Thang, D.C.; Nam, N.H.; Pontikis, R.; Pichat, L.

    1982-01-01

    dl-Methadone was resolved by crystallization of its ammonium d- α -bromocamphor-π-sulfonate salt to give d-methadone. The latter in ethyl acetate solution was reduced with tritium gas to 1-α-methadol 3H in presence of Adams platinum oxide at normal temperature and pressure. Acetylation of 1-α-carbinol hydrochloride by means of acetyl chloride afforded 1-α-acetylmethadol 3 H, specific activity: 20 Ci/mMole. The positions and extent of tritium labelling were determined by 3 H NMR spectroscopy. (author)

  16. Carob pod insoluble fiber exerts anti-atherosclerotic effects in rabbits through sirtuin-1 and peroxisome proliferator-activated receptor-γ coactivator-1α.

    Science.gov (United States)

    Valero-Muñoz, María; Martín-Fernández, Beatriz; Ballesteros, Sandra; Lahera, Vicente; de las Heras, Natalia

    2014-09-01

    The aim of this study was to evaluate the potential effects of an insoluble dietary fiber from carob pod (IFC) (1 g ⋅ kg(-1) ⋅ d(-1) in the diet) on alterations associated with atherosclerosis in rabbits with dyslipidemia. Male New Zealand rabbits (n = 30) were fed the following diets for 8 wk: 1) a control diet (SF412; Panlab) as a control group representing normal conditions; 2) a control supplemented with 0.5% cholesterol + 14% coconut oil (DL) (SF302; Panlab) for 8 wk as a dyslipidemic group; and 3) a control containing 0.5% cholesterol + 14% coconut oil plus IFC (1 g ⋅ kg(-1) ⋅ d(-1)) (DL+IFC) for 8 wk. IFC was administered in a pellet mixed with the DL diet. The DL-fed group developed mixed dyslipidemia and atherosclerotic lesions, which were associated with endothelial dysfunction, inflammation, and fibrosis. Furthermore, sirtuin-1 (SIRT1) and peroxisome proliferator-activated receptor-γ coactivator-1α (PGC-1α) protein expression in the aorta were reduced to 77% and 63% of the control group, respectively (P < 0.05), in these rabbits. Administration of IFC to DL-fed rabbits reduced the size of the aortic lesion significantly (DL, 15.2% and DL+IFC, 2.6%) and normalized acetylcholine-induced relaxation (maximal response: control, 89.3%; DL, 61.6%; DL+IFC, 87.1%; P < 0.05) and endothelial nitric oxide synthase expression (DL, 52% and DL+IFC, 104% of the control group). IFC administration to DL-fed rabbits also reduced cluster of differentiation 36 (DL, 148% and DL+IFC, 104% of the control group; P < 0.05), plasminogen activator inhibitor-1 (DL, 141% and DL+IFC, 107% of the control group), tumor necrosis factor-α (DL, 166% and DL+IFC, 120% of the control group), vascular cell adhesion molecule-1 (DL, 153% and DL+IFC, 110% of the control group), transforming growth factor-β (DL, 173% and DL+IFC, 99% of the control group), and collagen I (DL, 157% and DL+IFC, 112% of the control group) in the aorta. These effects were accompanied by an enhancement of

  17. El coactivador de receptores nucleares RAC3 tiene un rol protector de la Apoptosis inducida por distintos estímulos RAC3 nuclear receptor co-activator has a protective role in the apoptosis induced by different stimuli

    Directory of Open Access Journals (Sweden)

    Georgina P. Coló

    2007-10-01

    Full Text Available RAC3 pertenece a la familia de coactivadores de receptores nucleares p160, y se encuentra sobreexpresado en varios tumores. Demostramos previamente que RAC3 es coactivador del factor de transcripción anti-apoptótico NF-kapa;B. En este trabajo investigamos su rol en la apoptosis inducida por H2O2 en una línea celular no tumoral derivada de riñón embrionario humano (HEK293, y por el ligando inductor de apoptosis relacionado a TNF (TRAIL en una línea de leucemia mieloide crónica humana (K562, naturalmente resistente a la muerte por este estímulo. Observamos que las células tumorales K562 poseen niveles altos de RAC3 comparados con las células no tumorales HEK293. La sobreexpresión normal de coactivador o por transfección, inhibe la apoptosis mediante una disminución de la activación de caspasas, translocación del factor inductor de apoptosis (AIF al núcleo, aumento de la actividad de NF-kapa;B y las quinasas AKT y p38 y disminución de la quinasa ERK. Lo opuesto fue observado por disminución de RAC3 mediante la técnica de ARN interferente (RNAi en K562, aumentando así la apoptosis inducida por TRAIL. Estas evidencias sugieren que una sobreexpresión de RAC3 contribuye al desarrollo de tumores, participando en las cascadas que controlan la muerte celular por mecanismos no estrictamente dependientes de hormonas esteroideas y/o de acetilación, constituyendo esto un posible blanco de ataque para el tratamiento de tumores.RAC3 belongs to the family of p160 nuclear receptors coactivators and it is over-expressed in several tumors. We have previously shown that RAC3 is a NF-kappa;B coactivator. In this paper, we investigated the role of RAC3 in cell-sensitivity to apoptosis, using H2O2 in the human embryonic kidney cell line (HEK293, and tumor necrosis factor-related apoptosis inducing ligand (TRAIL in a human chronic myeloid leukemia cell line (K562 naturally resistant to TRAIL. We observed that the tumoral K562 cells have high levels

  18. Screening and association testing of common coding variation in steroid hormone receptor co-activator and co-repressor genes in relation to breast cancer risk: the Multiethnic Cohort

    Directory of Open Access Journals (Sweden)

    Stallcup Michael R

    2009-01-01

    Full Text Available Abstract Background Only a limited number of studies have performed comprehensive investigations of coding variation in relation to breast cancer risk. Given the established role of estrogens in breast cancer, we hypothesized that coding variation in steroid receptor coactivator and corepressor genes may alter inter-individual response to estrogen and serve as markers of breast cancer risk. Methods We sequenced the coding exons of 17 genes (EP300, CCND1, NME1, NCOA1, NCOA2, NCOA3, SMARCA4, SMARCA2, CARM1, FOXA1, MPG, NCOR1, NCOR2, CALCOCO1, PRMT1, PPARBP and CREBBP suggested to influence transcriptional activation by steroid hormone receptors in a multiethnic panel of women with advanced breast cancer (n = 95: African Americans, Latinos, Japanese, Native Hawaiians and European Americans. Association testing of validated coding variants was conducted in a breast cancer case-control study (1,612 invasive cases and 1,961 controls nested in the Multiethnic Cohort. We used logistic regression to estimate odds ratios for allelic effects in ethnic-pooled analyses as well as in subgroups defined by disease stage and steroid hormone receptor status. We also investigated effect modification by established breast cancer risk factors that are associated with steroid hormone exposure. Results We identified 45 coding variants with frequencies ≥ 1% in any one ethnic group (43 non-synonymous variants. We observed nominally significant positive associations with two coding variants in ethnic-pooled analyses (NCOR2: His52Arg, OR = 1.79; 95% CI, 1.05–3.05; CALCOCO1: Arg12His, OR = 2.29; 95% CI, 1.00–5.26. A small number of variants were associated with risk in disease subgroup analyses and we observed no strong evidence of effect modification by breast cancer risk factors. Based on the large number of statistical tests conducted in this study, the nominally significant associations that we observed may be due to chance, and will need to be confirmed in other

  19. Screening and association testing of common coding variation in steroid hormone receptor co-activator and co-repressor genes in relation to breast cancer risk: the Multiethnic Cohort

    International Nuclear Information System (INIS)

    Haiman, Christopher A; Stallcup, Michael R; Greene, Geoffrey L; Press, Michael F; Garcia, Rachel R; Hsu, Chris; Xia, Lucy; Ha, Helen; Sheng, Xin; Le Marchand, Loic; Kolonel, Laurence N; Henderson, Brian E

    2009-01-01

    Only a limited number of studies have performed comprehensive investigations of coding variation in relation to breast cancer risk. Given the established role of estrogens in breast cancer, we hypothesized that coding variation in steroid receptor coactivator and corepressor genes may alter inter-individual response to estrogen and serve as markers of breast cancer risk. We sequenced the coding exons of 17 genes (EP300, CCND1, NME1, NCOA1, NCOA2, NCOA3, SMARCA4, SMARCA2, CARM1, FOXA1, MPG, NCOR1, NCOR2, CALCOCO1, PRMT1, PPARBP and CREBBP) suggested to influence transcriptional activation by steroid hormone receptors in a multiethnic panel of women with advanced breast cancer (n = 95): African Americans, Latinos, Japanese, Native Hawaiians and European Americans. Association testing of validated coding variants was conducted in a breast cancer case-control study (1,612 invasive cases and 1,961 controls) nested in the Multiethnic Cohort. We used logistic regression to estimate odds ratios for allelic effects in ethnic-pooled analyses as well as in subgroups defined by disease stage and steroid hormone receptor status. We also investigated effect modification by established breast cancer risk factors that are associated with steroid hormone exposure. We identified 45 coding variants with frequencies ≥ 1% in any one ethnic group (43 non-synonymous variants). We observed nominally significant positive associations with two coding variants in ethnic-pooled analyses (NCOR2: His52Arg, OR = 1.79; 95% CI, 1.05–3.05; CALCOCO1: Arg12His, OR = 2.29; 95% CI, 1.00–5.26). A small number of variants were associated with risk in disease subgroup analyses and we observed no strong evidence of effect modification by breast cancer risk factors. Based on the large number of statistical tests conducted in this study, the nominally significant associations that we observed may be due to chance, and will need to be confirmed in other studies. Our findings suggest that common coding

  20. A cigarette component acrolein induces accelerated senescence in human diploid fibroblast IMR-90 cells.

    Science.gov (United States)

    Luo, Cheng; Li, Yan; Yang, Liang; Feng, Zhihui; Li, Yuan; Long, Jiangang; Liu, Jiankang

    2013-10-01

    Cigarette smoking causes various diseases, including lung cancer and cardiovascular disease, and reduces life span, though the mechanisms are not well understood. We hypothesize that smoking may cause cellular mitochondrial dysfunction and oxidative stress, leading to aging acceleration. In the present study, we tested the effects of acrolein, a major representative smoking toxicant, on human lung fibroblast IMR-90 cells with regard to cellular senescence, oxidative stress, and mitochondrial function. The results showed that subacute treatment with low dose of acrolein induces the following events compared to the control cells: cell senescence demonstrated by increases in the activity of β-galactosidase, the higher expression of p53 and p21, decreases in DNA synthesis, Sirt1 expression, and telomere length; oxidative stress occurred as the increases in the production of reactive oxygen species, DNA damage, and protein oxidation; and mitochondrial dysfunction shown as decreases in the mitochondrial membrane potential, mitochondrial biogenesis regulator PGC-1 alpha and mitochondria complex I, II, III, and V. These results suggest that acrolein may accelerate aging through the mechanism of increasing oxidative stress and mitochondrial dysfunction.

  1. SIRT1 deacetylase protects against neurodegeneration in models for Alzheimer's disease and amyotrophic lateral sclerosis.

    Science.gov (United States)

    Kim, Dohoon; Nguyen, Minh Dang; Dobbin, Matthew M; Fischer, Andre; Sananbenesi, Farahnaz; Rodgers, Joseph T; Delalle, Ivana; Baur, Joseph A; Sui, Guangchao; Armour, Sean M; Puigserver, Pere; Sinclair, David A; Tsai, Li-Huei

    2007-07-11

    A progressive loss of neurons with age underlies a variety of debilitating neurological disorders, including Alzheimer's disease (AD) and amyotrophic lateral sclerosis (ALS), yet few effective treatments are currently available. The SIR2 gene promotes longevity in a variety of organisms and may underlie the health benefits of caloric restriction, a diet that delays aging and neurodegeneration in mammals. Here, we report that a human homologue of SIR2, SIRT1, is upregulated in mouse models for AD, ALS and in primary neurons challenged with neurotoxic insults. In cell-based models for AD/tauopathies and ALS, SIRT1 and resveratrol, a SIRT1-activating molecule, both promote neuronal survival. In the inducible p25 transgenic mouse, a model of AD and tauopathies, resveratrol reduced neurodegeneration in the hippocampus, prevented learning impairment, and decreased the acetylation of the known SIRT1 substrates PGC-1alpha and p53. Furthermore, injection of SIRT1 lentivirus in the hippocampus of p25 transgenic mice conferred significant protection against neurodegeneration. Thus, SIRT1 constitutes a unique molecular link between aging and human neurodegenerative disorders and provides a promising avenue for therapeutic intervention.

  2. SIRT1 deacetylase protects against neurodegeneration in models for Alzheimer's disease and amyotrophic lateral sclerosis

    Science.gov (United States)

    Kim, Dohoon; Nguyen, Minh Dang; Dobbin, Matthew M; Fischer, Andre; Sananbenesi, Farahnaz; Rodgers, Joseph T; Delalle, Ivana; Baur, Joseph A; Sui, Guangchao; Armour, Sean M; Puigserver, Pere; Sinclair, David A; Tsai, Li-Huei

    2007-01-01

    A progressive loss of neurons with age underlies a variety of debilitating neurological disorders, including Alzheimer's disease (AD) and amyotrophic lateral sclerosis (ALS), yet few effective treatments are currently available. The SIR2 gene promotes longevity in a variety of organisms and may underlie the health benefits of caloric restriction, a diet that delays aging and neurodegeneration in mammals. Here, we report that a human homologue of SIR2, SIRT1, is upregulated in mouse models for AD, ALS and in primary neurons challenged with neurotoxic insults. In cell-based models for AD/tauopathies and ALS, SIRT1 and resveratrol, a SIRT1-activating molecule, both promote neuronal survival. In the inducible p25 transgenic mouse, a model of AD and tauopathies, resveratrol reduced neurodegeneration in the hippocampus, prevented learning impairment, and decreased the acetylation of the known SIRT1 substrates PGC-1alpha and p53. Furthermore, injection of SIRT1 lentivirus in the hippocampus of p25 transgenic mice conferred significant protection against neurodegeneration. Thus, SIRT1 constitutes a unique molecular link between aging and human neurodegenerative disorders and provides a promising avenue for therapeutic intervention. PMID:17581637

  3. Endothermy in birds: underlying molecular mechanisms.

    Science.gov (United States)

    Walter, Isabel; Seebacher, Frank

    2009-08-01

    Endothermy is significant in vertebrate evolution because it changes the relations between animals and their environment. How endothermy has evolved in archosaurs (birds, crocodiles and dinosaurs) is controversial especially because birds do not possess brown adipose tissue, the specialized endothermic tissue of mammals. Internal heat production is facilitated by increased oxidative metabolic capacity, accompanied by the uncoupling of aerobic metabolism from energy (ATP) production. Here we show that the transition from an ectothermic to an endothermic metabolic state in developing chicken embryos occurs by the interaction between increased basal ATP demand (Na(+)/K(+)-ATPase activity and gene expression), increased oxidative capacity and increased uncoupling of mitochondria; this process is controlled by thyroid hormone via its effect on PGC1alpha and adenine nucleotide translocase (ANT) gene expression. Mitochondria become more uncoupled during development, but unlike in mammals, avian uncoupling protein (avUCP) does not uncouple electron transport from oxidative phosphorylation and therefore plays no role in heat production. Instead, ANT is the principal uncoupling protein in birds. The relationship between oxidative capacity and uncoupling indicates that there is a continuum of phenotypes that fall between the extremes of selection for increased heat production and increased aerobic activity, whereas increased cellular ATP demand is a prerequisite for increased oxidative capacity.

  4. Impaired fat oxidation after a single high-fat meal in insulin-sensitive nondiabetic individuals with a family history of type 2 diabetes.

    Science.gov (United States)

    Heilbronn, Leonie K; Gregersen, Søren; Shirkhedkar, Deepali; Hu, Dachun; Campbell, Lesley V

    2007-08-01

    Individuals with insulin resistance and type 2 diabetes have an impaired ability to switch appropriately between carbohydrate and fatty acid oxidation. However, whether this is a cause or consequence of insulin resistance is unclear, and the mechanism(s) involved in this response is not completely elucidated. Whole-body fat oxidation and transcriptional regulation of genes involved in lipid metabolism in skeletal muscle were measured after a prolonged fast and after consumption of either high-fat (76%) or high-carbohydrate (76%) meals in individuals with no family history of type 2 diabetes (control, n = 8) and in age- and fatness-matched individuals with a strong family history of type 2 diabetes (n = 9). Vastus lateralis muscle biopsies were performed before and 3 h after each meal. Insulin sensitivity and fasting measures of fat oxidation were not different between groups. However, subjects with a family history of type 2 diabetes had an impaired ability to increase fatty acid oxidation in response to the high-fat meal (P FAT)/CD36 (P fat meal in both groups, but it was not changed after the high-carbohydrate meal. In conclusion, an impaired ability to increase fatty acid oxidation precedes the development of insulin resistance in genetically susceptible individuals. PGC1alpha and FAT/CD36 are likely candidates in mediating this response.

  5. Bioenergetics of lung tumors: alteration of mitochondrial biogenesis and respiratory capacity.

    Science.gov (United States)

    Bellance, N; Benard, G; Furt, F; Begueret, H; Smolková, K; Passerieux, E; Delage, J P; Baste, J M; Moreau, P; Rossignol, R

    2009-12-01

    Little is known on the metabolic profile of lung tumors and the reminiscence of embryonic features. Herein, we determined the bioenergetic profiles of human fibroblasts taken from lung epidermoid carcinoma (HLF-a) and fetal lung (MRC5). We also analysed human lung tumors and their surrounding healthy tissue from four patients with adenocarcinoma. On these different models, we measured functional parameters (cell growth rates in oxidative and glycolytic media, respiration, ATP synthesis and PDH activity) as well as compositional features (expression level of various energy proteins and upstream transcription factors). The results demonstrate that both the lung fetal and cancer cell lines produced their ATP predominantly by glycolysis, while oxidative phosphorylation was only capable of poor ATP delivery. This was explained by a decreased mitochondrial biogenesis caused by a lowered expression of PGC1alpha (as shown by RT-PCR and Western blot) and mtTFA. Consequently, the relative expression of glycolytic versus OXPHOS markers was high in these cells. Moreover, the re-activation of mitochondrial biogenesis with resveratrol induced cell death specifically in cancer cells. A consistent reduction of mitochondrial biogenesis and the subsequent alteration of respiratory capacity was also observed in lung tumors, associated with a lower expression level of bcl2. Our data give a better characterization of lung cancer cells' metabolic alterations which are essential for growth and survival. They designate mitochondrial biogenesis as a possible target for anti-cancer therapy.

  6. [Folates and fetal programming: role of epigenetics and epigenomics].

    Science.gov (United States)

    Guéant, Jean-Louis; Daval, Jean-Luc; Vert, Paul; Nicolas, Jean-Pierre

    2012-12-01

    Folates are needed for synthesis of methionine, the precursor of S-adenosyl methionine (SAM). They play therefore a key role in nutrition and epigenomics by fluxing monocarbons towards synthesis or methylation of DNA and RNA, and methylation of gene transregulators, respectively. The deficiency produces intrauterine growth retardation and birth dejects. Folate deficiency deregulates epigenomic mechanisms related to fetal programming through decreased cellular availability of SAM. Epigenetic mechanisms of folate deficiency are illustrated by inheritance of coat colour of agouti mice model and altered expression of Igf2/H19 imprinting genes. Dietary exposure to fumonisin FB1 acts synergistically with folate deficiency on alterations of heterochromatin assembly. Deficiency in folate and vitamin B12 produces impaired fatty acid oxidation in liver and heart through imbalanced methylation and acetylation of PGC1-alpha and decreased expression of SIRT1, and long-lasting cognitive disabilities through impaired hippocampal cell proliferation, differentiation and plasticity and atrophy of hippocampal CA1. Deciphering these mechanisms will help understand the discordances between experimental models and population studies on folate supplementation.

  7. IGF-II-mediated downregulation of peroxisome proliferator-activated receptor-γ coactivator-1α in myoblast cells involves PI3K/Akt/FoxO1 signaling pathway.

    Science.gov (United States)

    Mu, Xiaoyu; Qi, Weihong; Liu, Yunzhang; Zhou, Jianfeng; Li, Yun; Rong, Xiaozhi; Lu, Ling

    2017-08-01

    Insulin-like growth factor II (IGF-II) can stimulate myogenesis and is critically involved in skeletal muscle differentiation. The presence of negative regulators of this process, however, is not well explored. Here, we showed that in myoblast cells, IGF-II negatively regulated peroxisome proliferator-activated receptor-γ coactivator-1α (PGC-1α) mRNA expression, while constitutive expression of PGC-1α induced myoblast differentiation. These results suggest that the negative regulation of PGC-1α by IGF-II may act as a negative feedback mechanism in IGF-II-induced myogenic differentiation. Reporter assays demonstrated that IGF-II suppresses the basal PGC-1α promoter activity. Blocking the IGF-II signaling pathway increased the endogenous PGC-1α levels. In addition, pharmacological inhibition of PI3 kinase activity prevented the downregulation of PGC-1α but the activation of mTOR was not required for this process. Importantly, further analysis showed that forkhead transcription factor FoxO1 contributes to mediating the effects of IGF-II on PGC-1 promoter activity. These findings indicate that IGF-II reduces PGC-1α expression in skeletal muscle cells through a mechanism involving PI3K-Akt-FoxO1 but not p38 MAPK or Erk1/2 MAPK pathways.

  8. Erythroid Kruppel-like factor (EKLF) is recruited to the γ-globin gene promoter as a co-activator and is required for γ-globin gene induction by short-chain fatty acid derivatives

    Science.gov (United States)

    Perrine, Susan P.; Mankidy, Rishikesh; Boosalis, Michael S.; Bieker, James J.; Faller, Douglas V.

    2011-01-01

    Objectives The erythroid Kruppel-like factor (EKLF) is an essential transcription factor for β-type globin gene switching, and specifically activates transcription of the adult β-globin gene promoter. We sought to determine if EKLF is also required for activation of the γ-globin gene by short-chain fatty acid (SCFA) derivatives, which are now entering clinical trials. Methods The functional and physical interaction of EKLF and co-regulatory molecules with the endogenous human globin gene promoters was studied in primary human erythroid progenitors and cell lines, using chromatin immunoprecipitation (ChIP) assays and genetic manipulation of the levels of EKLF and co-regulators. Results and conclusions Knockdown of EKLF prevents SCFA-induced expression of the γ-globin promoter in a stably expressed μLCRβprRlucAγprFluc cassette, and prevents induction of the endogenous γ-globin gene in primary human erythroid progenitors. EKLF is actively recruited to endogenous γ-globin gene promoters after exposure of primary human erythroid progenitors, and murine hematopoietic cell lines, to SCFA derivatives. The core ATPase BRG1 subunit of the human SWI/WNF complex, a ubiquitous multimeric complex that regulates gene expression by remodeling nucleosomal structure, is also required for γ-globin gene induction by SCFA derivatives. BRG1 is actively recruited to the endogenous γ-globin promoter of primary human erythroid progenitors by exposure to SCFA derivatives, and this recruitment is dependent upon the presence of EKLF. These findings demonstrate that EKLF, and the co-activator BRG1, previously demonstrated to be required for definitive or adult erythropoietic patterns of globin gene expression, are co-opted by SCFA derivatives to activate the fetal globin genes. PMID:19220418

  9. Functional co-activation within the prefrontal cortex supports the maintenance of behavioural performance in fear-relevant situations before an iTBS modulated virtual reality challenge in participants with spider phobia.

    Science.gov (United States)

    Deppermann, S; Notzon, S; Kroczek, A; Rosenbaum, D; Haeussinger, F B; Diemer, J; Domschke, K; Fallgatter, A J; Ehlis, A-C; Zwanzger, P

    2016-07-01

    A number of studies/meta-analyses reported moderate antidepressant effects of activating repetitive transcranial magnetic stimulation (rTMS) over the prefrontal cortex (PFC). Regarding the treatment of anxiety, study outcomes are inconsistent, probably because of the heterogenity of anxiety disorders/study designs. To specifically evaluate the impact of rTMS on emotion regulation in fear-relevant situations we applied a sham-controlled activating protocol (intermittent Theta Burst Stimulation/iTBS) over the left PFC (F3) succeeded by a virtual reality (VR) challenge in n=41 participants with spider phobia and n=42 controls. Prior to/after iTBS and following VR prefrontal activation was assessed by functional near-infrared spectroscopy during an emotional Stroop paradigm. Performance (reaction times/error rates) was evaluated. Stimuli were rated regarding valence/arousal at both measurements. We found diminished activation in the left inferior frontal gyrus (IFG) of participants with spider phobia compared to controls, particularly elicited by emotionally-irrelevant words. Simultaneously, a functional connectivity analysis showed increased co-activation between the left IFG and the contra-lateral hemisphere. Behavioural performance was unimpaired. After iTBS/VR no significant differences in cortical activation between the phobic and control group remained. However, verum-iTBS did not cause an additional augmentation. We interpreted our results in terms of a prefrontal network which gets activated by emotionally-relevant stimuli and supports the maintenance of adequate behavioural reactions. The missing add-on effects of iTBS might be due to a ceiling effect of VR, thereby supporting its potential during exposure therapy. Concurrently, it implies that the efficient application of iTBS in the context of emotion regulation still needs to be studied further. Copyright © 2016 Elsevier B.V. All rights reserved.

  10. Potential antisecretory antidiarrheals. 1. Alpha 2-adrenergic aromatic aminoguanidine hydrazones.

    Science.gov (United States)

    Pitzele, B S; Moormann, A E; Gullikson, G W; Albin, D; Bianchi, R G; Palicharla, P; Sanguinetti, E L; Walters, D E

    1988-01-01

    Guanabenz, a centrally acting antihypertensive agent, has been shown to have intestinal antisecretory properties. A series of aromatic aminoguanidine hydrazones was made in an effort to separate the antisecretory and cardiovascular activities. Benzaldehyde, naphthaldehyde, and tetralone derivatives were synthesized. The compounds were evaluated in the cholera toxin treated ligated jejunum of the rat and in the Ussing chamber using a rabbit ileum preparation. A number of compounds, including members of each structural class, were active upon subcutaneous administration in the rat. Active compounds were determined to be alpha 2-adrenergic agonists by yohimbine reversals of their Ussing chamber activities. The compound displaying the best separation of activities was the aminoguanidine hydrazone of 2,6-dimethyl-4-hydroxybenzaldehyde (20).

  11. Novel Polymorphisms of Adrenergic, Alpha-1B-, Receptor and Peroxisome Proliferator-activated Receptor Gamma, Coactivator 1 Beta Genes and Their Association with Egg Production Traits in Local Chinese Dagu Hens

    Directory of Open Access Journals (Sweden)

    F. Mu

    2016-09-01

    Full Text Available Adrenergic, alpha-1B-, receptor (ADRA1B and peroxisome proliferator-activated receptor gamma, coactivator 1 beta (PPARGC1B genes are involved in regulation of hen ovarian development. In this study, these two genes were investigated as possible molecular markers associated with hen-housed egg production, egg weight (EW and body weight in Chinese Dagu hens. Samples were analyzed using the polymerase chain reaction-single strand conformation polymorphism (PCR-SSCP technique, followed by sequencing analysis. Two novel single nucleotide polymorphisms (SNPs were identified within the candidate genes. Among them, an A/G transition at base position 1915 in exon 2 of ADRA1B gene and a T/C mutation at base position 6146 in the 3′-untranslated region (UTR of PPARGC1B gene were found to be polymorphic and named SNP A1915G and T6146C, respectively. The SNP A1915G (ADRA1B leads to a non-synonymous substitution (aspartic acid 489-to-glycine. The 360 birds from the Dagu population were divided into genotypes AA and AG, allele A was found to be present at a higher frequency. Furthermore, the AG genotype correlated with significantly higher hen-housed egg production (HHEP at 30, 43, 57, and 66 wks of age and with a higher EW at 30 and 43 wks (p<0.05. For the SNP T6146C (PPARGC1B, the hens were typed into TT and TC genotypes, with the T allele shown to be dominant. The TC genotype was also markedly correlated with higher HHEP at 57 and 66 wks of age and EW at 30 and 43 wks (p<0.05. Moreover, four haplotypes were reconstructed based on these two SNPs, with the AGTC haplotype found to be associated with the highest HHEP at 30 to 66 wks of age and with higher EW at 30 and 43 wks (p<0.05. Collectively, the two SNPs identified in this study might be used as potential genetic molecular markers favorable in the improvement of egg productivity in chicken breeding.

  12. Hypoxia inducible factor-1 is activated by transcriptional co-activator with PDZ-binding motif (TAZ) versus WWdomain-containing oxidoreductase (WWOX) in hypoxic microenvironment of bone metastasis from breast cancer.

    Science.gov (United States)

    Bendinelli, Paola; Maroni, Paola; Matteucci, Emanuela; Luzzati, Alessandro; Perrucchini, Giuseppe; Desiderio, Maria Alfonsina

    2013-07-01

    The hypoxic microenvironment of bone marrow favours the bone metastasis process. Hypoxia inducible factor (HIF)-1α is hallmark for hypoxia, correlating with poor prognosis and radio/chemotherapy resistance of primary-breast carcinoma. For bone metastasis, the molecular mechanisms involved in HIF-1α expression and HIF-1 (α/β heterodimer)-transcription factor activity are scarcely known. We studied the role played by HIF-1 in the cross-talk between neoplastic and supportive-microenvironmental cells. Also, WWdomain-containing oxidoreductase (Wwox) and transcriptional co-activator with PDZ-binding motif (TAZ) were taken into consideration evaluating whether these Hippo-pathway effectors affect bone-metastatic phenotype through HIF-1 activity. Considering bone-metastasis specimens, nuclear HIF-1α-TAZ co-localisation occurred in neoplastic and supportive cells, such as fibroblasts and endotheliocytes. Based on these data, the functional importance was verified using 1833-bone metastatic clone under hypoxia: nuclear HIF-1α and TAZ expression increased and co-immunoprecipitated, activating HIF-1-DNA binding and transactivation. In contrast, Wwox localised at perinuclear level in neoplastic cells of bone metastasis, being almost absent in supportive cells, and Wwox-protein expression diminished in hypoxic-1833 cells. Thus, TAZ regulation of HIF-1 activity might be important for bone-secondary growth, participating in metastasis-stroma cross-talk. Further, TAZ and HIF-1α-protein levels seemed correlated. In fact, blocking cyclooxygenase-2 with NS398 in hypoxic-1833 cells, not only HIF-1α decreased but also molecular-mechanism(s) upstream of the Hippo pathway were triggered: LATS-dependent TAZ phosphorylation seemed responsible for TAZ nucleus/cytoplasm translocation and degradation. In the 1833-xenograft model, NS398 largely prevented the outgrowth of bone-metastatic cells, probably related to remarkable-extracellular matrix assembly. We gained clinical insight into

  13. cis-Stilbene and (1 alpha,2 beta,3 alpha)-(2-ethenyl-3-methoxycyclopropyl)benzene as mechanistic probes in the Mn(III)(salen)-catalyzed epoxidation: influence of the oxygen source and the counterion on the diastereoselectivity of the competitive concerted and radical-type oxygen transfer.

    Science.gov (United States)

    Adam, Waldemar; Roschmann, Konrad J; Saha-Möller, Chantu R; Seebach, Dieter

    2002-05-08

    cis-Stilbene (1) has been epoxidized by a set of diverse oxygen donors [OxD], catalyzed by the Mn(III)(salen)X complexes 3 (X = Cl, PF(6)), to afford a mixture of cis- and trans-epoxides 2. The cis/trans ratios range from 29:71 (extensive isomerization) to 92:8, which depends both on the oxygen source [OxD] and on the counterion X of the catalyst. When (1 alpha,2 beta,3 alpha)-(2-ethenyl-3-methoxycyclopropyl)-benzene (4) is used as substrate, a mechanistic probe which differentiates between radical and cationic intermediates, no cationic ring-opening products are found in this epoxidation reaction; thus, isomerized epoxide product arises from intermediary radicals. The dependence of the diastereoselectivity on the oxygen source is rationalized in terms of a bifurcation step in the catalytic cycle, in which concerted Lewis-acid-activated oxygen transfer competes with stepwise epoxidation by the established Mn(V)(oxo) species. The experimental counterion effect is attributed to the computationally assessed ligand-dependent reaction profiles and stereoselectivities of the singlet, triplet, and quintet spin states available to the manganese species.

  14. Serum levels of pancreatic stone protein (PSP/reg1A as an indicator of beta-cell apoptosis suggest an increased apoptosis rate in hepatocyte nuclear factor 1 alpha (HNF1A-MODY carriers from the third decade of life onward

    Directory of Open Access Journals (Sweden)

    Bacon Siobhan

    2012-07-01

    Full Text Available Abstract Background Mutations in the transcription factor hepatocyte nuclear factor-1-alpha (HNF1A result in the commonest type of maturity onset diabetes of the young (MODY. HNF1A-MODY carriers have reduced pancreatic beta cell mass, partially due to an increased rate of apoptosis. To date, it has not been possible to determine when apoptosis is occurring in HNF1A-MODY.We have recently demonstrated that beta cell apoptosis stimulates the expression of the pancreatic stone protein/regenerating (PSP/reg gene in surviving neighbour cells, and that PSP/reg1A protein is subsequently secreted from these cells. The objective of this study was to determine whether serum levels of PSP/reg1A are elevated during disease progression in HNF1A-MODY carriers, and whether it may provide information regarding the onset of beta-cell apoptosis. Methods We analysed serum PSP/reg1A levels and correlated with clinical and biochemical parameters in subjects with HNF1A-MODY, glucokinase (GCK-MODY, and type 1 diabetes mellitus. A control group of normoglycaemic subjects was also analysed. Results PSP/reg1A serum levels were significantly elevated in HNF1A-MODY (n = 37 subjects compared to controls (n = 60 (median = 12.50 ng/ml, IQR = 10.61-17.87 ng/ml versus median = 10.72 ng/ml, IQR = 8.94-12.54 ng/ml, p = 0.0008. PSP/reg1A correlated negatively with insulin levels during OGTT, (rho = −0.40, p = 0.02. Interestingly we noted a significant positive correlation of PSP/reg1A with age of the HNF1A-MODY carriers (rho = 0.40 p = 0.02 with an age of 25 years separating carriers with low and high PSP/reg1A levels. Patients with type 1 diabetes mellitus also had elevated serum levels of PSP/reg1A compared to controls, however this was independent of the duration of diabetes. Conclusion Our data suggest that beta cell apoptosis contributes increasingly to the pathophysiology of HNF1A-MODY in patients 25 years and over

  15. Serum levels of pancreatic stone protein (PSP)/reg1A as an indicator of beta-cell apoptosis suggest an increased apoptosis rate in hepatocyte nuclear factor 1 alpha (HNF1A-MODY) carriers from the third decade of life onward

    LENUS (Irish Health Repository)

    Bacon, Siobhan

    2012-07-18

    AbstractBackgroundMutations in the transcription factor hepatocyte nuclear factor-1-alpha (HNF1A) result in the commonest type of maturity onset diabetes of the young (MODY). HNF1A-MODY carriers have reduced pancreatic beta cell mass, partially due to an increased rate of apoptosis. To date, it has not been possible to determine when apoptosis is occurring in HNF1A-MODY.We have recently demonstrated that beta cell apoptosis stimulates the expression of the pancreatic stone protein\\/regenerating (PSP\\/reg) gene in surviving neighbour cells, and that PSP\\/reg1A protein is subsequently secreted from these cells. The objective of this study was to determine whether serum levels of PSP\\/reg1A are elevated during disease progression in HNF1A-MODY carriers, and whether it may provide information regarding the onset of beta-cell apoptosis.MethodsWe analysed serum PSP\\/reg1A levels and correlated with clinical and biochemical parameters in subjects with HNF1A-MODY, glucokinase (GCK-MODY), and type 1 diabetes mellitus. A control group of normoglycaemic subjects was also analysed.ResultsPSP\\/reg1A serum levels were significantly elevated in HNF1A-MODY (n = 37) subjects compared to controls (n = 60) (median = 12.50 ng\\/ml, IQR = 10.61-17.87 ng\\/ml versus median = 10.72 ng\\/ml, IQR = 8.94-12.54 ng\\/ml, p = 0.0008). PSP\\/reg1A correlated negatively with insulin levels during OGTT, (rho = −0.40, p = 0.02). Interestingly we noted a significant positive correlation of PSP\\/reg1A with age of the HNF1A-MODY carriers (rho = 0.40 p = 0.02) with an age of 25 years separating carriers with low and high PSP\\/reg1A levels. Patients with type 1 diabetes mellitus also had elevated serum levels of PSP\\/reg1A compared to controls, however this was independent of the duration of diabetes.ConclusionOur data suggest that beta cell apoptosis contributes increasingly to the pathophysiology of HNF1A-MODY in patients 25 years and

  16. A rich medium-chain triacylglycerol diet benefits adiposity but has adverse effects on the markers of hepatic lipogenesis and beta-oxidation.

    Science.gov (United States)

    Chamma, Carolina Maria de Oliveira; Bargut, Thereza Cristina Lonzetti; Mandarim-de-Lacerda, Carlos Alberto; Aguila, Marcia Barbosa

    2017-02-22

    We investigated the increasing amounts of medium-chain triacylglycerol (MCT) in the diet on hepatic lipid metabolism. Mature C57BL/6 male mice were randomly divided into five groups (n = 10/group). The animals received their diet for 12 weeks, as a control (C group, 10% of energy from lipids); high-fat lard (HF group, isoenergetic diet, 50% of energy from lipids with lard); a mixture of lard and MCT oil (with a gradual replacement of lard by MCT: HF-MCT25%, HF-MCT75%, and HF-MCT100% groups). At euthanasia, we collected blood and dissected the liver for analyses (glucose, insulin, HOMA-IR, QUICK index, and triacylglycerol, light microscopy, western blotting, and RT-qPCR). The HF diet groups showed a greater body mass gain compared to the C group, but the HF-MCT100% group showed diminished adiposity and amelioration of insulin resistance. All the HF groups also showed a clear increase in hepatic lipid accumulation, increased lipogenesis and decreased PPAR-alpha expression, although HF-MCT groups showed improved local insulin signaling. Lastly, the HF-MCT100% group had raised markers of beta-oxidation (UCP3 and MCAD) and mitochondrial biogenesis (PGC1-alpha and NRF1). In conclusion, the findings demonstrated that a high amount of MCT (HF-MCT100% group) added to an HF diet reduces the body fat accumulation and insulin resistance. However, the lipid accumulation as well as the lipid metabolism is altered in the liver of animals fed with a very high MCT diet, indicating that higher doses of MCT may be harmful in a long-term.

  17. Protecting Neural Structures and Cognitive Function During Prolonged Space Flight by Targeting the Brain Derived Neurotrophic Factor Molecular Network

    Science.gov (United States)

    Schmidt, M. A.; Goodwin, T. J.

    2014-01-01

    Brain derived neurotrophic factor (BDNF) is the main activity-dependent neurotrophin in the human nervous system. BDNF is implicated in production of new neurons from dentate gyrus stem cells (hippocampal neurogenesis), synapse formation, sprouting of new axons, growth of new axons, sprouting of new dendrites, and neuron survival. Alterations in the amount or activity of BDNF can produce significant detrimental changes to cortical function and synaptic transmission in the human brain. This can result in glial and neuronal dysfunction, which may contribute to a range of clinical conditions, spanning a number of learning, behavioral, and neurological disorders. There is an extensive body of work surrounding the BDNF molecular network, including BDNF gene polymorphisms, methylated BDNF gene promoters, multiple gene transcripts, varied BDNF functional proteins, and different BDNF receptors (whose activation differentially drive the neuron to neurogenesis or apoptosis). BDNF is also closely linked to mitochondrial biogenesis through PGC-1alpha, which can influence brain and muscle metabolic efficiency. BDNF AS A HUMAN SPACE FLIGHT COUNTERMEASURE TARGET Earth-based studies reveal that BDNF is negatively impacted by many of the conditions encountered in the space environment, including oxidative stress, radiation, psychological stressors, sleep deprivation, and many others. A growing body of work suggests that the BDNF network is responsive to a range of diet, nutrition, exercise, drug, and other types of influences. This section explores the BDNF network in the context of 1) protecting the brain and nervous system in the space environment, 2) optimizing neurobehavioral performance in space, and 3) reducing the residual effects of space flight on the nervous system on return to Earth

  18. Improved inflammatory balance of human skeletal muscle during exercise after supplementations of the ginseng-based steroid Rg1.

    Directory of Open Access Journals (Sweden)

    Chien-Wen Hou

    Full Text Available The purpose of the study was to determine the effect of ginseng-based steroid Rg1 on TNF-alpha and IL-10 gene expression in human skeletal muscle against exercise challenge, as well as on its ergogenic outcomes. Randomized double-blind placebo-controlled crossover trials were performed, separated by a 4-week washout. Healthy young men were randomized into two groups and received capsule containing either 5 mg of Rg1 or Placebo one night and one hour before exercise. Muscle biopsies were conducted at baseline, immediately and 3 h after a standardized 60-min cycle ergometer exercise. While treatment differences in glycogen depletion rate of biopsied quadriceps muscle during exercise did not reach statistical significance, Rg1 supplementations enhanced post-exercise glycogen replenishment and increased citrate synthase activity in the skeletal muscle 3 h after exercise, concurrent with improved meal tolerance during recovery (P<0.05. Rg1 suppressed the exercise-induced increases in thiobarbituric acids reactive substance (TBARS and reversed the increased TNF-alpha and decreased IL-10 mRNA of quadriceps muscle against the exercise challenge. PGC-1 alpha and GLUT4 mRNAs of exercised muscle were not affected by Rg1. Maximal aerobic capacity (VO2max was not changed by Rg1. However, cycling time to exhaustion at 80% VO2max increased significantly by ~20% (P<0.05.Our result suggests that Rg1 is an ergogenic component of ginseng, which can minimize unwanted lipid peroxidation of exercised human skeletal muscle, and attenuate pro-inflammatory shift under exercise challenge.

  19. Improved inflammatory balance of human skeletal muscle during exercise after supplementations of the ginseng-based steroid Rg1.

    Science.gov (United States)

    Hou, Chien-Wen; Lee, Shin-Da; Kao, Chung-Lan; Cheng, I-Shiung; Lin, Yu-Nan; Chuang, Sheng-Ju; Chen, Chung-Yu; Ivy, John L; Huang, Chih-Yang; Kuo, Chia-Hua

    2015-01-01

    The purpose of the study was to determine the effect of ginseng-based steroid Rg1 on TNF-alpha and IL-10 gene expression in human skeletal muscle against exercise challenge, as well as on its ergogenic outcomes. Randomized double-blind placebo-controlled crossover trials were performed, separated by a 4-week washout. Healthy young men were randomized into two groups and received capsule containing either 5 mg of Rg1 or Placebo one night and one hour before exercise. Muscle biopsies were conducted at baseline, immediately and 3 h after a standardized 60-min cycle ergometer exercise. While treatment differences in glycogen depletion rate of biopsied quadriceps muscle during exercise did not reach statistical significance, Rg1 supplementations enhanced post-exercise glycogen replenishment and increased citrate synthase activity in the skeletal muscle 3 h after exercise, concurrent with improved meal tolerance during recovery (P<0.05). Rg1 suppressed the exercise-induced increases in thiobarbituric acids reactive substance (TBARS) and reversed the increased TNF-alpha and decreased IL-10 mRNA of quadriceps muscle against the exercise challenge. PGC-1 alpha and GLUT4 mRNAs of exercised muscle were not affected by Rg1. Maximal aerobic capacity (VO2max) was not changed by Rg1. However, cycling time to exhaustion at 80% VO2max increased significantly by ~20% (P<0.05). Our result suggests that Rg1 is an ergogenic component of ginseng, which can minimize unwanted lipid peroxidation of exercised human skeletal muscle, and attenuate pro-inflammatory shift under exercise challenge.

  20. Conserved and differential effects of dietary energy intake on the hippocampal transcriptomes of females and males.

    Directory of Open Access Journals (Sweden)

    Bronwen Martin

    2008-06-01

    Full Text Available The level of dietary energy intake influences metabolism, reproductive function, the development of age-related diseases, and even cognitive behavior. Because males and females typically play different roles in the acquisition and allocation of energy resources, we reasoned that dietary energy intake might differentially affect the brains of males and females at the molecular level. To test this hypothesis, we performed a gene array analysis of the hippocampus in male and female rats that had been maintained for 6 months on either ad libitum (control, 20% caloric restriction (CR, 40% CR, intermittent fasting (IF or high fat/high glucose (HFG diets. These diets resulted in expected changes in body weight, and circulating levels of glucose, insulin and leptin. However, the CR diets significantly increased the size of the hippocampus of females, but not males. Multiple genes were regulated coherently in response to energy restriction diets in females, but not in males. Functional physiological pathway analyses showed that the 20% CR diet down-regulated genes involved in glycolysis and mitochondrial ATP production in males, whereas these metabolic pathways were up-regulated in females. The 40% CR diet up-regulated genes involved in glycolysis, protein deacetylation, PGC-1alpha and mTor pathways in both sexes. IF down-regulated many genes in males including those involved in protein degradation and apoptosis, but up-regulated many genes in females including those involved in cellular energy metabolism, cell cycle regulation and protein deacetylation. Genes involved in energy metabolism, oxidative stress responses and cell death were affected by the HFG diet in both males and females. The gender-specific molecular genetic responses of hippocampal cells to variations in dietary energy intake identified in this study may mediate differential behavioral responses of males and females to differences in energy availability.

  1. In vitro cellular adaptations of indicators of longevity in response to treatment with serum collected from humans on calorie restricted diets.

    Directory of Open Access Journals (Sweden)

    Joanne S Allard

    2008-09-01

    Full Text Available Calorie restriction (CR produces several health benefits and increases lifespan in many species. Studies suggest that alternate-day fasting (ADF and exercise can also provide these benefits. Whether CR results in lifespan extension in humans is not known and a direct investigation is not feasible. However, phenotypes observed in CR animals when compared to ad libitum fed (AL animals, including increased stress resistance and changes in protein expression, can be simulated in cells cultured with media supplemented with blood serum from CR and AL animals. Two pilot studies were undertaken to examine the effects of ADF and CR on indicators of health and longevity in humans. In this study, we used sera collected from those studies to culture human hepatoma cells and assessed the effects on growth, stress resistance and gene expression. Cells cultured in serum collected at the end of the dieting period were compared to cells cultured in serum collected at baseline (before the dieting period. Cells cultured in serum from ADF participants, showed a 20% increase in Sirt1 protein which correlated with reduced triglyceride levels. ADF serum also induced a 9% decrease in proliferation and a 25% increase in heat resistance. Cells cultured in serum from CR participants induced an increase in Sirt1 protein levels by 17% and a 30% increase in PGC-1alpha mRNA levels. This first in vitro study utilizing human serum to examine effects on markers of health and longevity in cultured cells resulted in increased stress resistance and an up-regulation of genes proposed to be indicators of increased longevity. The use of this in vitro technique may be helpful for predicting the potential of CR, ADF and other dietary manipulations to affect markers of longevity in humans.

  2. Diverse coactivator recruitment through differential PPARγ nuclear receptor agonism

    Directory of Open Access Journals (Sweden)

    Fernando Lizcano

    2013-01-01

    Full Text Available The PPARγ nuclear receptor regulates the expression of genes involved in lipid and carbohydrate metabolism, and it has protective effects in some patients with type 2 diabetes. Nevertheless, the therapeutic value of the PPARγ nuclear receptor protein is limited due to the secondary effects of some PPARγ ligands. Because the downstream effects of PPARγ are determined by the binding of specific cofactors that are mediated by ligand-induced conformational changes, we evaluated the differential effects of various ligands on the binding of certain cofactors associated with PPARγ. The ligands used were rosiglitazone for treating type 2 diabetes and telmisartan for treating arterial hypertension. Functional, phenotypic, and molecular studies were conducted on pre-adipocyte 3T3-L1 and functional studies in U2OS cells. The moderating influence of various cofactor families was evaluated using transient transfection assays. Our findings confirm that telmisartan has a partial modulating effect on PPARγ activity compared to rosiglitazone. The cofactors SRC1 and GRIP1 mediate the activity of telmisartan and rosiglitazone and partially determine the difference in their effects. Studying the modulating activity of these cofactors can provide interesting insights for developing new therapeutic approaches for certain metabolic diseases.

  3. Can co-activation reduce kinematic variability? A simulation study.

    NARCIS (Netherlands)

    Selen, L.P.J.; Beek, P.J.; van Dieen, J.H.

    2005-01-01

    Impedance modulation has been suggested as a means to suppress the effects of internal 'noise' on movement kinematics. We investigated this hypothesis in a neuro-musculo-skeletal model. A prerequisite is that the muscle model produces realistic force variability. We found that standard Hill-type

  4. Regulated degradation of the APC coactivator Cdc20

    Directory of Open Access Journals (Sweden)

    Robbins Jonathan A

    2010-09-01

    Full Text Available Abstract Background Cdc20 is a highly conserved activator of the anaphase-promoting complex (APC, promoting cell-cycle-regulated ubiquitination and proteolysis of a number of critical cell-cycle-regulatory targets including securin and mitotic cyclins. APC-Cdc20 activity is tightly regulated, and this regulation is likely important for accurate cell cycle control. One significant component of Cdc20 regulation is thought to be Cdc20 proteolysis. However, published literature suggests different mechanisms and requirements for Cdc20 proteolysis. The degree to which Cdc20 proteolysis is cell-cycle regulated, the dependence of Cdc20 proteolysis on Cdc20 destruction boxes (recognition sequences for APC-mediated ubiqutination, either by Cdc20 or by the related Cdh1 APC activator, and the need for APC itself for Cdc20 proteolysis all have been disputed to varying extents. In animals, Cdc20 proteolysis is thought to be mediated by Cdh1, contributing an intrinsic order of APC activation by Cdc20 and then by Cdh1. One report suggests a Cdh1 requirement for Cdc20 proteolysis in budding yeast; this idea has not been tested further. Results We characterized Cdc20 proteolysis using Cdc20 expressed from its endogenous locus; previous studies generally employed strongly overexpressed Cdc20, which can cause significant artifacts. We analyzed Cdc20 proteolysis with or without mutations in previously identified destruction box sequences, using varying methods of cell cycle synchronization, and in the presence or absence of Cdh1. Cdc20 instability is only partially dependent on destruction boxes. A much stronger dependence on Cdh1 for Cdc20 proteolysis was observed, but Cdh1-independent proteolysis was also clearly observed. Cdc20 proteolysis independent of both destruction boxes and Cdh1 was especially detectable around the G1/S transition; Cdh1-dependent proteolysis was most notable in late mitosis and G1. Conclusions Cdc20 proteolysis is under complex control, with different systems operating at different points in the cell cycle. This complexity is likely to explain apparent conflicts in previously published literature on this subject. A major mode of control of Cdc20 proteolysis occurs in late mitosis/early G1 and is Cdh1-dependent, as in animal cells; this mode may contribute to the known sequential activation of the APC by Cdc20 followed by Cdh1. An independent mode of Cdc20 proteolysis, independent of destruction boxes and Cdh1, occurs at G1/S; we do not know the mechanism or function of this mode of proteolysis, but speculate that it may contribute to sharpening and restricting activation of APC-Cdc20 to early mitosis.

  5. All-trans retinoic acid increases oxidative metabolism in mature adipocytes

    DEFF Research Database (Denmark)

    Mercader, Josep; Madsen, Lise; Felipe, Francisco

    2007-01-01

    ), and to an increased expression of proteins favoring fat oxidation (peroxisome proliferator-activated receptor gamma coactivator-1alpha, uncoupling protein 2, fasting-induced adipose factor, enzymes of mitochondrial fatty acid oxidation). These changes paralleled inactivation of the retinoblastoma protein and were...

  6. Mathematical Model of HIF-1 alpha Pathway, Oxygen Transport and Hypoxia

    Science.gov (United States)

    2017-09-01

    succinate inhibition and PHD negative feedback. Yucel & Kumaz 2007 Sensitivity of the angiogenic behaviour of a cancer cell to PHD and FIH. Dayan et al...With CF computed, CB can be calculated, and finally the CA leaving the gas exchange region. 3.2 HIF-1α Mathematical Model for Brain A...is dictated by the partial pressure of that gas in blood versus luminal contents. For methane and hydrogen, diffusion is always out of the lumen

  7. Interleukin 1 alpha increases the susceptibility of rabbits to experimental viridans streptococcal endocarditis

    NARCIS (Netherlands)

    Dankert, J; Joldersma, W; Zaat, SAJ; van der Werff, J.

    Major predisposing conditions for infective endocarditis (IE) are the presence of a cardiac platelet-fibrin vegetation and of circulating bacteria with relatively low susceptibility to microbicidal activity of blood platelets. The influence of proinflammatory conditions on development of IE is

  8. The Role of SDF-1alpha and CXCR4 in Metastatic Breast Cancer

    Science.gov (United States)

    2006-08-01

    investigations are needed to establish the cause and effect relationship of survivin gene regulation and 3,3V-diindolylmethane-induced cell growth...Chem 2002;277:29674-29680. 32. Basu GD, Pathangey LB, Tinder TL, et al. Cyclooxygenase-2 inhibitor induces apoptosis in breast cancer cells in an in

  9. Melatonin promotes cardiomyogenesis of embryonic stem cells via inhibition of HIF-1 alpha stabilization

    Czech Academy of Sciences Publication Activity Database

    Kudová, Jana; Vašíček, Ondřej; Číž, Milan; Kubala, Lukáš

    2016-01-01

    Roč. 61, č. 4 (2016), s. 493-503 ISSN 0742-3098 R&D Projects: GA MŠk(CZ) LD14030 Institutional support: RVO:68081707 Keywords : prostate -cancer cells * increased vascular-permeability * reperfusion injury Subject RIV: BO - Biophysics Impact factor: 10.391, year: 2016

  10. The role of hypoxia inducible factor-1 alpha in bypassing oncogene-induced senescence.

    Directory of Open Access Journals (Sweden)

    Mehtap Kilic Eren

    Full Text Available Oncogene induced senescence (OIS is a sustained anti-proliferative response acutely induced in primary cells via activation of mitogenic oncogenes such as Ras/BRAF. This mechanism acts as an initial barrier preventing normal cells transformation into malignant cell. Besides oncogenic activation and DNA damage response (DDR, senescence is modulated by a plethora of other factors, and one of the most important one is oxygen tension of the tissue. The aim of this study was to determine the impact of hypoxia on RasV12-induced senescence in human diploid fibroblasts (HDFs. We showed here that hypoxia prevents execution of oncogene induced senescence (OIS, through a strong down-regulation of senescence hallmarks, such as SA- β-galactosidase, H3K9me3, HP1γ, p53, p21CIP1 and p16INK4a in association with induction of hypoxia inducible factor-1α (HIF-1α. In addition, hypoxia also decreased marks of H-RasV12-induced DDR in both cell lines through down-regulation of ATM/ATR, Chk1 and Chk2 phosphorylation as well as decreased γ-H2AX positivity. Utilizing shRNA system targeting HIF-1α we show that HIF-1α is directly involved in down regulation of p53 and its target p21CIP1 but not p16INK4a. In line with this finding we found that knock down of HIF-1α leads to a strong induction of apoptotic response, but not restoration of senescence in Ras expressing HDFs in hypoxia. This indicates that HIF-1α is an important player in early steps of tumorigenesis, leading to suppression of senescence through its negative regulation of p53 and p21CIP1. In our work we describe a mechanism through which hypoxia and specifically HIF-1α preclude cells from maintaining senescence-driven anti proliferative response. These findings indicate the possible mechanism through which hypoxic environment helps premalignant cells to evade impingement of cellular failsafe pathways.

  11. Neural Differentiation Is Inhibited through HIF1 alpha/ beta-Catenin Signaling in Embryoid Bodies

    Czech Academy of Sciences Publication Activity Database

    Veceřa, J.; Kudová, Jana; Kučera, J.; Kubala, Lukáš; Pachernik, J.

    2017-01-01

    Roč. 2017, č. 2017 (2017), č. článku 8715798. ISSN 1687-966X Institutional support: RVO:68081707 Keywords : stem- cell fate * hypoxia * oxygen Subject RIV: EB - Genetics ; Molecular Biology OBOR OECD: Genetics and heredity (medical genetics to be 3) Impact factor: 3.540, year: 2016

  12. Development of a Combination Therapy for Prostate Cancer by Targeting Stat3 and HIF-1alpha

    Science.gov (United States)

    2013-07-01

    inflammation-induced cancer, making it an attractive target (25-27). A3. Innovation 1. TEL03 is a novel anti-cancer agent from Chinese herbal medicine ...agents from Chinese herbal medicine (CHM) that targets HIF-1α /2α for prostate cancer therapy. Hypoxia orchestrated by HIF-1αis crucial for tumor...Stat3 for treatment of prostate and other cancers. TEL03, which is a novel anti-cancer agent derived from Chinese herbal medicine (CHM: Hypocrella

  13. Cx43, ZO-1, alpha-catenin and beta-catenin in cataractous lens ...

    Indian Academy of Sciences (India)

    2012-10-17

    Oct 17, 2012 ... physical association between neighboring cells and hold them together (Meng ..... radiation (Zigman et al. 1979), diabetes and vascular dis- .... JO 2003 Decreased caspase-3 activity in human lens epithelium from posterior ...

  14. Phenotypic and functional markers for 1alpha,25-dihydroxyvitamin D(3)-modified regulatory dendritic cells

    DEFF Research Database (Denmark)

    Pedersen, A W; Holmstrøm, K; Jensen, S S

    2009-01-01

    The clinical use of dendritic cells (DCs) to induce antigen-specific immune tolerance has been hampered by the lack of a widely acknowledged method for generating human regulatory DCs but even more so by the non-existence of reliable markers. Thus, we set out to find reliable markers that can...... CD14 and reduced CD1a on the cell surface. These VD3-treated DCs exert a long-lasting inefficient T cell stimulation and induce T cell hyporesponsiveness with regulatory potential. Importantly, such VD3-treated DCs were readily distinguishable from untreated DCs by low levels of interleukin-23...

  15. Induction of regulatory dendritic cells by dexamethasone and 1alpha,25-Dihydroxyvitamin D(3)

    DEFF Research Database (Denmark)

    Pedersen, Anders Elm; Gad, Monika; Walter, Mark R

    2004-01-01

    D(3) the active form of Vitamin D(3) (D(3)) in combination with dexamethasone (Dex) has a synergistic effect on LPS-induced maturation of DC. Monocyte-derived DCs cultured with D(3) and Dex during LPS-induced maturation have a low stimulatory effect on allogeneic T cells comparable...

  16. PDH-E1alpha dephosphorylation and activation in human skeletal muscle during exercise

    DEFF Research Database (Denmark)

    Pilegaard, Henriette; Birk, Jesper Bratz; Sacchetti, Massimo

    2006-01-01

    . Phosphorylation had returned to resting levels at 3 h of exercise only in the control trial. Thus, an inverse association between PDH-E1a phosphorylation and PDHa activity exists. Short-term elevation in plasma FFA at rest increases PDH-E1a phosphorylation, but exercise overrules this effect of FFA on PDH-E1a...... extensor exercise at moderate intensity. During the 4-h resting period, activity of PDH in the active form (PDHa) did not change in either trial, yet phosphorylation of PDH-E1a site 1 (PDH-P1) and site 2 (PDH-P2) was elevated in the intralipid compared with the control trial. PDHa activity increased during...... exercise similarly in the two trials. After 3 h of exercise, PDHa activity remained elevated in the intralipid trial but returned to resting levels in the control trial. Accordingly, in both trials PDH-P1 and PDH-P2 decreased during exercise, and the decrease was more marked during intralipid infusion...

  17. Functional polymorphism of IL-1 alpha and its potential role in obesity in humans and mice.

    Directory of Open Access Journals (Sweden)

    Jae-Young Um

    Full Text Available Proinflammatory cytokines secreted from adipose tissue contribute to the morbidity associated with obesity. IL-1α is one of the proinflammatory cytokines; however, it has not been clarified whether IL-1α may also cause obesity. In this study, we investigated whether polymorphisms in IL-1α contribute to human obesity. A total of 260 obese subjects were genotyped for IL-1α C-889T (rs1800587 and IL-1α G+4845T (rs17561. Analyses of genotype distributions revealed that both IL-1α polymorphisms C-889T (rs1800587 and G+4845T (rs17561 were associated with an increase in body mass index in obese healthy women. In addition, the effect of rs1800587 on the transcriptional activity of IL-1α was explored in pre-adipocyte 3T3-L1 cells. Significant difference was found between the rs1800587 polymorphism in the regulatory region of the IL-1α gene and transcriptional activity. We extended these observations in vivo to a high-fat diet-induced obese mouse model and in vitro to pre-adipocyte 3T3-L1 cells. IL-1α levels were dramatically augmented in obese mice, and triglyceride was increased 12 hours after IL-1α injection. Taken together, IL-1α treatment regulated the differentiation of preadipocytes. IL-1α C-889T (rs1800587 is a functional polymorphism of IL-1α associated with obesity. IL-1α may have a critical function in the development of obesity.

  18. 1 ALPHA-Hydroxyvitamin D5 as a Chemotherapeutic and Possibly Chemopreventive Agent

    National Research Council Canada - National Science Library

    Das Gupta, Tapas K

    2004-01-01

    ...; high doses led to a hypercalcemic effect, which was reversible. In vitro studies showed that D5 has no effect on normal breast epithelial cells but induces apoptosis in breast cancer and showed apoptotic effect in fibroadenomas...

  19. Cx43, ZO-1, alpha-catenin and beta-catenin in cataractous lens

    Indian Academy of Sciences (India)

    Specimens of the anterior lens capsule with an attached monolayer of lens epithelial cells (LECs) were obtained from patients (=52) undergoing cataract surgery. Specimens were divided into three groups based on the type of cataract: nuclear cataract, cortical cataract and posterior subcapsular cataract (PSC).

  20. Variants in the interleukin-1 alpha and beta genes, and the risk for ...

    Indian Academy of Sciences (India)

    Japan). An initial volume of 250 μL was used and a final volume of 200 μL elution buffer (CDT) was obtained. ... the software SPSS (Statistical Package for Social Sciences) ver. ..... central role in multiple interactions and regulatory networks.

  1. 1-Alpha Hydroxyvitamin D(5) as a Chemotherapeutic and Possibly Chemopreventive Agent

    Science.gov (United States)

    2007-03-01

    GTT GCT GTT TGT TTG AC, and the antisense primer was 50-CTT CTG TGA GGC TGT TTT TG. The primer for the housekeeping gene G3PDH was purchased from...reverse-transcribed. The cDNA was ampli- fied using Taq polymerase and separated on 1.5% agarose gel. As shown in Fig. 5, the housekeeping gene G3PDH (C...control housekeeping gene. 784 G. Lazzaro et al. / European Journal of Cancer 36 (2000) 780±786 Appendix 3. Publications DAMD17-99-1-9223 – Final

  2. 1 ALPHA-Hydroxyvitamin D5 as a Chemotherapeutic and Possibly Chemopreventive Agent

    Science.gov (United States)

    2004-09-01

    cancer cells. TTT TG. The primer -for the housekeeping gene G3PDH was purchased from ClonTech. The touchdown 3.2. Induction of differentiation of breast...the housekeeping gene The effects of vitamin D analogues as differentiating G3PDH (C) was identical for all the cDNAs, indicating . agents and...control housekeeping gene. "* G. Lazzaro et al. / European Journal of Cancer 36 (2000) 780-786 785 levels of VDR, do not respond to active vitamin D p53

  3. Host - HIF- 1alpha Pathway And Hypoxia: In Vitro Studies And Mathematical Model

    Science.gov (United States)

    2016-08-30

    E., Del Sal, G., Gustincich, S . (2010). Parkinson disease-associated DJ-1 required for the expression of the glial cell line-derived neurotrophic...other provision of law , no person shall be subject to any penalty for failing to comply with a collection of information if it does not display a...Model 5a. CONTRACT NUMBER In-House 5b. GRANT NUMBER NA 5c. PROGRAM ELEMENT NUMBER 62202F 6. AUTHOR( S ) Robinson, Peter J.1, Molly E. Chapleau1

  4. Prognostic role of hypoxia-inducible factor-1 alpha expression in osteosarcoma: a meta-analysis

    Directory of Open Access Journals (Sweden)

    Ren HY

    2016-03-01

    Full Text Available Hai-Yong Ren,1 Yin-Hua Zhang,1,2 Heng-Yuan Li,1 Tao Xie,1 Ling-Ling Sun,1 Ting Zhu,1 Sheng-Dong Wang,1 Zhao-Ming Ye1 1Department of Orthopaedics, Second Affiliated Hospital, College of Medicine, Zhejiang University, Hangzhou, 2The First Department of Orthopaedics, Hospital of Zhejiang General Corps of Armed Police Forces, Jiaxing, People’s Republic of China Background: Hypoxia-inducible factor-1α (HIF-1α plays an important role in tumor progression and metastasis. A number of studies have investigated the association of HIF-1α with prognosis and clinicopathological characteristics of osteosarcoma but yielded inconsistent results.  Method: Systematic computerized searches were performed in PubMed, Embase, and Web of Science databases for relevant original articles. The pooled hazard ratios (HRs and odds ratios (ORs with corresponding confidence intervals (CIs were calculated to assess the prognostic value of HIF-1α expression. The standard mean difference was used to analyze the continuous variable.  Results: Finally, nine studies comprising 486 patients were subjected to final analysis. Protein expression level of HIF-1α was found to be significantly related to overall survival (HR =3.0; 95% CI: 1.46–6.15, disease-free survival (HR =2.23; 95% CI: 1.26–3.92, pathologic grade (OR =21.33; 95% CI: 4.60–98.88, tumor stage (OR =10.29; 95% CI: 3.55–29.82, chemotherapy response (OR =9.68; 95% CI: 1.87–50.18, metastasis (OR =5.06; 95% CI: 2.87–8.92, and microvessel density (standard mean difference =2.83; 95% CI: 2.28–3.39.  Conclusion: This meta-analysis revealed that overexpression of HIF-1α is a predictive factor of poor outcomes for osteosarcoma. HIF-1α appeared to play an important role in prognostic evaluation and may be a potential target in antitumoral therapy. Keywords: HIF-1α, osteosarcoma, prognosis, meta-analysis

  5. Direct Thy-1/alphaVbeta3 integrin interaction mediates neuron to astrocyte communication.

    Science.gov (United States)

    Hermosilla, Tamara; Muñoz, Daniel; Herrera-Molina, Rodrigo; Valdivia, Alejandra; Muñoz, Nicolás; Nham, Sang-Uk; Schneider, Pascal; Burridge, Keith; Quest, Andrew F G; Leyton, Lisette

    2008-06-01

    Thy-1 is an abundant neuronal glycoprotein of poorly defined function. We recently provided evidence indicating that Thy-1 clusters a beta3-containing integrin in astrocytes to induce tyrosine phosphorylation, RhoA activation and the formation of focal adhesions and stress fibers. To date, the alpha subunit partner of beta3 integrin in DI TNC1 astrocytes is unknown. Similarly, the ability of neuronal, membrane-bound Thy-1 to trigger astrocyte signaling via integrin engagement remains speculation. Here, evidence that alphav forms an alphavbeta3 heterodimer in DI TNC1 astrocytes was obtained. In neuron-astrocyte association assays, the presence of either anti-alphav or anti-beta3 integrin antibodies reduced cell-cell interaction demonstrating the requirement of both integrin subunits for this association. Moreover, anti-Thy-1 antibodies blocked stimulation of astrocytes by neurons but not the binding of these two cell types. Thus, neuron-astrocyte association involved binding between molecular components in addition to the Thy-1-integrin; however, the signaling events leading to focal adhesion formation in astrocytes depended exclusively on the latter interaction. Additionally, wild-type (RLD) but not mutated (RLE) Thy-1 was shown to directly interact with alphavbeta3 integrin by Surface Plasmon Resonance analysis. This interaction was promoted by divalent cations and was species-independent. Together, these results demonstrate that the alphavbeta3 integrin heterodimer interacts directly with Thy-1 present on neuronal cells to stimulate astrocytes.

  6. The histone deacetylase inhibitor, Vorinostat, represses hypoxia inducible factor 1 alpha expression through translational inhibition.

    Directory of Open Access Journals (Sweden)

    Darren M Hutt

    Full Text Available Hypoxia inducible factor 1α (HIF-1α is a master regulator of tumor angiogenesis being one of the major targets for cancer therapy. Previous studies have shown that Histone Deacetylase Inhibitors (HDACi block tumor angiogenesis through the inhibition of HIF-1α expression. As such, Vorinostat (Suberoylanilide Hydroxamic Acid/SAHA and Romidepsin, two HDACis, were recently approved by the Food and Drug Administration (FDA for the treatment of cutaneous T cell lymphoma. Although HDACis have been shown to affect HIF-1α expression by modulating its interactions with the Hsp70/Hsp90 chaperone axis or its acetylation status, the molecular mechanisms by which HDACis inhibit HIF-1α expression need to be further characterized. Here, we report that the FDA-approved HDACi Vorinostat/SAHA inhibits HIF-1α expression in liver cancer-derived cell lines, by a new mechanism independent of p53, prolyl-hydroxylases, autophagy and proteasome degradation. We found that SAHA or silencing of HDAC9 mechanism of action is due to inhibition of HIF-1α translation, which in turn, is mediated by the eukaryotic translation initiation factor--eIF3G. We also highlighted that HIF-1α translation is dramatically inhibited when SAHA is combined with eIF3H silencing. Taken together, we show that HDAC activity regulates HIF-1α translation, with HDACis such as SAHA representing a potential novel approach for the treatment of hepatocellular carcinoma.

  7. Hypoxia-induced cytotoxic drug resistance in osteosarcoma is independent of HIF-1Alpha.

    Directory of Open Access Journals (Sweden)

    Jennifer Adamski

    Full Text Available Survival rates from childhood cancer have improved dramatically in the last 40 years, such that over 80% of children are now cured. However in certain subgroups, including metastatic osteosarcoma, survival has remained stubbornly poor, despite dose intensive multi-agent chemotherapy regimens, and new therapeutic approaches are needed. Hypoxia is common in adult solid tumours and is associated with treatment resistance and poorer outcome. Hypoxia induces chemotherapy resistance in paediatric tumours including neuroblastoma, rhabdomyosarcoma and Ewing's sarcoma, in vitro, and this drug resistance is dependent on the oxygen-regulated transcription factor hypoxia inducible factor-1 (HIF-1. In this study the effects of hypoxia on the response of the osteosarcoma cell lines 791T, HOS and U2OS to the clinically relevant cytotoxics cisplatin, doxorubicin and etoposide were evaluated. Significant hypoxia-induced resistance to all three agents was seen in all three cell lines and hypoxia significantly reduced drug-induced apoptosis. Hypoxia also attenuated drug-induced activation of p53 in the p53 wild-type U2OS osteosarcoma cells. Drug resistance was not induced by HIF-1α stabilisation in normoxia by cobalt chloride nor reversed by the suppression of HIF-1α in hypoxia by shRNAi, siRNA, dominant negative HIF or inhibition with the small molecule NSC-134754, strongly suggesting that hypoxia-induced drug resistance in osteosarcoma cells is independent of HIF-1α. Inhibition of the phosphoinositide 3-kinase (PI3K pathway using the inhibitor PI-103 did not reverse hypoxia-induced drug resistance, suggesting the hypoxic activation of Akt in osteosarcoma cells does not play a significant role in hypoxia-induced drug resistance. Targeting hypoxia is an exciting prospect to improve current anti-cancer therapy and combat drug resistance. Significant hypoxia-induced drug resistance in osteosarcoma cells highlights the potential importance of hypoxia as a target to reverse drug resistance in paediatric osteosarcoma. The novel finding of HIF-1α independent drug resistance suggests however other hypoxia related targets may be more relevant in paediatric osteosarcoma.

  8. Effect of a HIF-1 Alpha Polymorphism on the Incidence and Prostate Cancer

    Science.gov (United States)

    2007-02-01

    factor levels and risk of prostate cancer. Cancer Epidemiol Biomarkers Prev 2005;14(6):1557-1561. 34. Percy MJ, Mooney SM, McMullin MF, Flores A...vascular endothelial growth factor in pathological angiogenesis. Breast Cancer Research & Treatment 1995;36(2):127-137. 37. Jackson MW, Bentel JM, Tilley

  9. A genome-wide siRNA screen to identify modulators of insulin sensitivity and gluconeogenesis.

    Directory of Open Access Journals (Sweden)

    Ruojing Yang

    Full Text Available BACKGROUND: Hepatic insulin resistance impairs insulin's ability to suppress hepatic glucose production (HGP and contributes to the development of type 2 diabetes (T2D. Although the interests to discover novel genes that modulate insulin sensitivity and HGP are high, it remains challenging to have a human cell based system to identify novel genes. METHODOLOGY/PRINCIPAL FINDINGS: To identify genes that modulate hepatic insulin signaling and HGP, we generated a human cell line stably expressing beta-lactamase under the control of the human glucose-6-phosphatase (G6PC promoter (AH-G6PC cells. Both beta-lactamase activity and endogenous G6PC mRNA were increased in AH-G6PC cells by a combination of dexamethasone and pCPT-cAMP, and reduced by insulin. A 4-gene High-Throughput-Genomics assay was developed to concomitantly measure G6PC and pyruvate-dehydrogenase-kinase-4 (PDK4 mRNA levels. Using this assay, we screened an siRNA library containing pooled siRNA targeting 6650 druggable genes and identified 614 hits that lowered G6PC expression without increasing PDK4 mRNA levels. Pathway analysis indicated that siRNA-mediated knockdown (KD of genes known to positively or negatively affect insulin signaling increased or decreased G6PC mRNA expression, respectively, thus validating our screening platform. A subset of 270 primary screen hits was selected and 149 hits were confirmed by target gene KD by pooled siRNA and 7 single siRNA for each gene to reduce G6PC expression in 4-gene HTG assay. Subsequently, pooled siRNA KD of 113 genes decreased PEPCK and/or PGC1alpha mRNA expression thereby demonstrating their role in regulating key gluconeogenic genes in addition to G6PC. Last, KD of 61 of the above 113 genes potentiated insulin-stimulated Akt phosphorylation, suggesting that they suppress gluconeogenic gene by enhancing insulin signaling. CONCLUSIONS/SIGNIFICANCE: These results support the proposition that the proteins encoded by the genes identified in

  10. Cancer metabolism meets systems biology: Pyruvate kinase isoform PKM2 is a metabolic master regulator

    OpenAIRE

    Fabian V Filipp

    2013-01-01

    Pyruvate kinase activity is controlled by a tightly woven regulatory network. The oncofetal isoform of pyruvate kinase (PKM2) is a master regulator of cancer metabolism. PKM2 engages in parallel, feed-forward, positive and negative feedback control contributing to cancer progression. Besides its metabolic role, non-metabolic functions of PKM2 as protein kinase and transcriptional coactivator for c-MYC and hypoxia-inducible factor 1-alpha are essential for epidermal growth factor receptor acti...

  11. HIF1-alpha overexpression indicates a good prognosis in early stage squamous cell carcinomas of the oral floor

    International Nuclear Information System (INIS)

    Fillies, Thomas; Werkmeister, Richard; Diest, Paul J van; Brandt, Burkhard; Joos, Ulrich; Buerger, Horst

    2005-01-01

    Hypoxia-inducible factor 1 (HIF-1) is a transcription factor, which plays a central role in biologic processes under hypoxic conditions, especially concerning tumour angiogenesis. HIF-1α is the relevant, oxygen-dependent subunit and its overexpression has been associated with a poor prognosis in a variety of malignant tumours. Therefore, HIF-1α expression in early stage oral carcinomas was evaluated in relation to established clinico-pathological features in order to determine its value as a prognostic marker. 85 patients with histologically proven surgically treated T1/2 squamous cell carcinoma (SCC) of the oral floor were eligible for the study. Tumor specimens were investigated by means of tissue micro arrays (TMAs) and immunohistochemistry for the expression of HIF-1. Correlations between clinical features and the expression of HIF-1 were evaluated by Kaplan-Meier curves, log-rank tests and multivariate Cox regression analysis. HIF-1α was frequently overexpressed in a probably non-hypoxia related fashion. The expression of HIF-1α was related with a significantly improved 5-year survival rate (p < 0.01) and a significantly increased disease free period (p = 0.01) independent from nodal status and tumour size. In primary node negative T1/T2 SCC of the oral floor, absence of HIF-1α expression specified a subgroup of high-risk patients (p < 0.05). HIF-1α overexpression is an indicator of favourable prognosis in T1 and T2 SCC of the oral floor. Node negative patients lacking HIF-1α expression may therefore be considered for adjuvant radiotherapy

  12. HIF-1 Alpha and Placental Growth Factor in Pregnancies Complicated With Preeclampsia: A Qualitative and Quantitative Analysis.

    Science.gov (United States)

    Rath, Gayatri; Aggarwal, Ruby; Jawanjal, Poonam; Tripathi, Richa; Batra, Aruna

    2016-01-01

    The pathophysiology of preeclampsia is not clearly understood worldwide. Hypoxia inducible factor 1α (HIF-1α) is thought to be the preliminary factor for the hypoxic conditions prevailing in preeclampsia, which causes imbalance in the expression of angiogenic proteins. A proangiogenic protein, placental growth factor (PIGF), is reported to be dysregulated in preeclampsia. Therefore, this study focuses on the investigation of HIF-1α and PIGF in preeclamptic conditions and a possible molecular association between them. Placental tissue (n = 45 + 45) and serum samples (n = 80 + 80) of preeclamptic patients and healthy control were collected and processed for the analysis of HIF-1α and PIGF by immunohistochemistry and enzyme-linked immunosorbent assay (ELISA). In preeclamptic group, the significant nuclear and cytoplasmic expression of HIF-1α was noticed in syncytiotrophoblast (P = 0.0001) but in control placenta, it was localized to cytoplasm (P = 0.0001). The intensity of PIGF expression was lower in syncytiotrophoblast cytoplasm (P = 0.0001) in preeclamptic cases as compared with control. Also, the significant upregulated concentration of HIF-1α and downregulated PIGF was observed in serum samples of preeclamptic woman (P = 0.0001). Thus, there was a significant direct negative correlation between HIF-1α and PIGF both at tissue and serum level (P preeclampsia. © 2014 Wiley Periodicals, Inc.

  13. HNF1 alpha gene coding regions mutations screening, in a Caucasian population clinically characterized as MODY from Argentina.

    Science.gov (United States)

    Lopez, Ariel Pablo; Foscaldi, Sabrina Andrea; Perez, Maria Silvia; Rodriguez, Martín; Traversa, Mercedes; Puchulu, Félix Miguel; Bergada, Ignacio; Frechtel, Gustavo Daniel

    2011-02-01

    There are at least six subtypes of Maturity Onset Diabetes of the Young (MODY) with distinctive genetic causes. MODY 3 is caused by mutations in HNF1A gene, an insulin transcription factor, so mutations in this gene are associated with impaired insulin secretion. MODY 3 prevalence differs according to the population analyzed, but it is one of the most frequent subtypes. Therefore, our aims in this work were to find mutations present in the HNF1A gene and provide information on their prevalence. Mutations screening was done in a group of 80 unrelated patients (average age 17.1 years) selected by clinical characterization of MODY, by SSCP electrophoresis followed by sequenciation. We found eight mutations, of which six were novel and four sequence variants, which were all novel. Therefore the prevalence of MODY 3 in this group was 10%. Compared clinical data between the non-MODY 3 patients and the MODY 3 diagnosed patients did not show any significant difference. Eight patients were diagnosed as MODY 3 and new data about the prevalence of that subtype is provided. Our results contribute to reveal novel mutations, providing new data about the prevalence of that subtype. Copyright © 2010 Elsevier Ireland Ltd. All rights reserved.

  14. Hepatocyte nuclear factor 1-alpha mutation in normal glucose-tolerant subjects and early-onset type 2 diabetic patients

    OpenAIRE

    Lim, Dong Mee; Huh, Nam; Park, Keun Yong

    2008-01-01

    Background/Aims The prevalence of diabetes in Korea is reported to be approximately 10%, but cases of maturity-onset diabetes of the young (MODY) are rare in Korea. A diagnostic technique for autosomal dominant MODY is being actively sought. In this regard, we used a DNA chip to investigate the frequency of mutations of the MODY3 gene (hepatocyte nuclear factor-1?) in Korean patients with early-onset type 2 diabetes. Methods The genomic DNA of 30 normal individuals [age, 24.9?8.6 years] and 2...

  15. Vaccination with Eimeria tenella Elongation Factor-1alpha Recombinant Protein Induces protective Immunity against E. tenella and E. maxima infections

    Science.gov (United States)

    Avian coccidiosis is caused by multiple species of the apicomplexan protozoan, Eimeria, and is one of the most economically devastating enteric diseases for the poultry industry worldwide. Host immunity to Eimeria infection, however, is relatively species-specific. The ability to immunize chickens a...

  16. On the almost everywhere convergence of the eigenfunction expansions from Liouville classes L_1^\\alpha ({T^N})

    Science.gov (United States)

    Ahmedov, Anvarjon; Materneh, Ehab; Zainuddin, Hishamuddin

    2017-09-01

    The relevance of waves in quantum mechanics naturally implies that the decomposition of arbitrary wave packets in terms of monochromatic waves plays an important role in applications of the theory. When eigenfunction expansions does not converge, then the expansions of the functions with certain smoothness should be considered. Such functions gained prominence primarily through their application in quantum mechanics. In this work we study the almost everywhere convergence of the eigenfunction expansions from Liouville classes L_p^α ({T^N}), related to the self-adjoint extension of the Laplace operator in torus TN . The sufficient conditions for summability is obtained using the modified Poisson formula. Isomorphism properties of the elliptic differential operators is applied in order to obtain estimation for the Fourier series of the functions from the classes of Liouville L_p^α .

  17. Hypoxia determines survival outcomes of bacterial infection through HIF-1alpha dependent re-programming of leukocyte metabolism *

    OpenAIRE

    Thompson, A.A.R.; Dickinson, R.S.; Murphy, F.; Thomson, J. P.; Marriott, H.M.; Tavares, A.; Willson, J.; Williams, L.; Lewis, A.; Mirchandani, A.; Dos Santos Coelho, P.; Doherty, C.; Ryan, E.; Watts, E.; Morton, N. M.

    2017-01-01

    Hypoxia and bacterial infection frequently co-exist, in both acute and chronic clinical settings, and typically result in adverse clinical outcomes. To ameliorate this morbidity, we investigated the interaction between hypoxia and the host response. In the context of acute hypoxia, both S. aureus and S. pneumoniae infections rapidly induced progressive neutrophil mediated morbidity and mortality, with associated hypothermia and cardiovascular compromise. Preconditioning animals through longer...

  18. Casein kinase 1 alpha regulates chromosome congression and separation during mouse oocyte meiotic maturation and early embryo development.

    Directory of Open Access Journals (Sweden)

    Lu Wang

    Full Text Available Casein kinase I alpha (CK1α is a member of serine/threonine protein kinase, generally present in all eukaryotes. In mammals, CK1α regulates the transition from interphase to metaphase in mitosis. However, little is known about its role in meiosis. Here we examined Ck1α mRNA and protein expression, as well as its subcellular localization in mouse oocytes from germinal vesicle to the late 1-cell stage. Our results showed that the expression level of CK1α was increased in metaphase. Immunostaining results showed that CK1α colocalized with condensed chromosomes during oocyte meiotic maturation and early embryo development. We used the loss-of-function approach by employing CK1α specific morpholino injection to block the function of CK1α. This functional blocking leads to failure of polar body 1 (PB1 extrusion, chromosome misalignment and MII plate incrassation. We further found that D4476, a specific and efficient CK1 inhibitor, decreased the rate of PB1 extrusion. Moreover, D4476 resulted in giant polar body extrusion, oocyte pro-MI arrest, chromosome congression failure and impairment of embryo developmental potential. In addition, we employed pyrvinium pamoate (PP, an allosteric activator of CK1α, to enhance CK1α activity in oocytes. Supplementation of PP induced oocyte meiotic maturation failure, severe congression abnormalities and misalignment of chromosomes. Taken together, our study for the first time demonstrates that CK1α is required for chromosome alignment and segregation during oocyte meiotic maturation and early embryo development.

  19. Ubiquitination is absolutely required for the degradation of hypoxia-inducible factor - 1 alpha protein in hypoxic conditions

    International Nuclear Information System (INIS)

    Wang, Ronghai; Zhang, Ping; Li, Jinhang; Guan, Hongzai; Shi, Guangjun

    2016-01-01

    The hypoxia-inducible factor (HIF) is recognized as the master regulator of hypoxia response. HIF-α subunits expression are tightly regulated. In this study, our data show that ts20 cells still expressed detectable E1 protein even at 39.5° C for 12 h, and complete depletion of E1 protein expression at 39.5° C by siRNA enhanced HIF-1α and P53 protein expression. Further inhibition of E1 at 39.5 °C by siRNA, or E1 inhibitor Ube1-41 completely blocked HIF-1α degradation. Moreover, immunoprecipitations of co-transfection of HA-ubiquitin and FLAG–HIF–1α plasmids directly confirmed the involvement of ubiquitin in the hypoxic degradation of HIF-1α. Additionally, hypoxic HIF-1 α degradation is independent of HAF, RACK1, sumoylation or nuclear/cytoplasmic localization. Taken together, our data suggest that constitutive HIF-1α protein degradation in hypoxia is absolutely ubiquitination-dependent, and unidentified E3 ligase may exist for this degradation pathway. - Highlights: • HIF-1α protein is constitutively degraded in hypoxic conditions. • Requirement of ubiquitination for HIF-1α degradation in hypoxia. • Hypoxic HIF-1α degradation is independent of HAF, RACK1, sumoylation or nuclear/cytoplasmic localization.

  20. Ubiquitination is absolutely required for the degradation of hypoxia-inducible factor--1 alpha protein in hypoxic conditions.

    Science.gov (United States)

    Wang, Ronghai; Zhang, Ping; Li, Jinhang; Guan, Hongzai; Shi, Guangjun

    2016-01-29

    The hypoxia-inducible factor (HIF) is recognized as the master regulator of hypoxia response. HIF-α subunits expression are tightly regulated. In this study, our data show that ts20 cells still expressed detectable E1 protein even at 39.5° C for 12 h, and complete depletion of E1 protein expression at 39.5° C by siRNA enhanced HIF-1α and P53 protein expression. Further inhibition of E1 at 39.5 °C by siRNA, or E1 inhibitor Ube1-41 completely blocked HIF-1α degradation. Moreover, immunoprecipitations of co-transfection of HA-ubiquitin and FLAG-HIF-1α plasmids directly confirmed the involvement of ubiquitin in the hypoxic degradation of HIF-1α. Additionally, hypoxic HIF-1 α degradation is independent of HAF, RACK1, sumoylation or nuclear/cytoplasmic localization. Taken together, our data suggest that constitutive HIF-1α protein degradation in hypoxia is absolutely ubiquitination-dependent, and unidentified E3 ligase may exist for this degradation pathway. Copyright © 2016 Elsevier Inc. All rights reserved.

  1. Ubiquitination is absolutely required for the degradation of hypoxia-inducible factor - 1 alpha protein in hypoxic conditions

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Ronghai [Department of Urology, Linzi District People' s Hospital, Zibo, 255400 (China); Zhang, Ping, E-mail: zpskx001@163.com [Department of Gynecology, Qingdao Municipal Hospital, Qingdao, 266011 (China); Li, Jinhang [Department of Gynecology, Qingdao Municipal Hospital, Qingdao, 266011 (China); Guan, Hongzai [Laboratory Department, School of Medicine, Qingdao University, Qingdao, 266071 (China); Shi, Guangjun, E-mail: qdmhshigj@yahoo.com [Department of Hepatobiliary Surgery, Qingdao Municipal Hospital, Qingdao, 266071 (China)

    2016-01-29

    The hypoxia-inducible factor (HIF) is recognized as the master regulator of hypoxia response. HIF-α subunits expression are tightly regulated. In this study, our data show that ts20 cells still expressed detectable E1 protein even at 39.5° C for 12 h, and complete depletion of E1 protein expression at 39.5° C by siRNA enhanced HIF-1α and P53 protein expression. Further inhibition of E1 at 39.5 °C by siRNA, or E1 inhibitor Ube1-41 completely blocked HIF-1α degradation. Moreover, immunoprecipitations of co-transfection of HA-ubiquitin and FLAG–HIF–1α plasmids directly confirmed the involvement of ubiquitin in the hypoxic degradation of HIF-1α. Additionally, hypoxic HIF-1 α degradation is independent of HAF, RACK1, sumoylation or nuclear/cytoplasmic localization. Taken together, our data suggest that constitutive HIF-1α protein degradation in hypoxia is absolutely ubiquitination-dependent, and unidentified E3 ligase may exist for this degradation pathway. - Highlights: • HIF-1α protein is constitutively degraded in hypoxic conditions. • Requirement of ubiquitination for HIF-1α degradation in hypoxia. • Hypoxic HIF-1α degradation is independent of HAF, RACK1, sumoylation or nuclear/cytoplasmic localization.

  2. Expression of DDX3 is directly modulated by hypoxia inducible factor-1 alpha in breast epithelial cells.

    Directory of Open Access Journals (Sweden)

    Mahendran Botlagunta

    2011-03-01

    Full Text Available DEAD box protein, DDX3, is aberrantly expressed in breast cancer cells ranging from weakly invasive to aggressive phenotypes and functions as an important regulator of cancer cell growth and survival. Here, we demonstrate that hypoxia inducible factor-1α is a transcriptional activator of DDX3 in breast cancer cells. Within the promoter region of the human DDX3 gene, we identified three putative hypoxia inducible factor-1 responsive elements. By luciferase reporter assays in combination with mutated hypoxia inducible factor-1 responsive elements, we determined that the hypoxia inducible factor-1 responsive element at position -153 relative to the translation start site is essential for transcriptional activation of DDX3 under hypoxic conditions. We also demonstrated that hypoxia inducible factor-1 binds to the DDX3 promoter and that the binding is specific, as revealed by siRNA against hypoxia inducible factor-1 and chromatin immunoprecipitation assays. Thus, the activation of DDX3 expression during hypoxia is due to the direct binding of hypoxia inducible factor-1 to hypoxia responsive elements in the DDX3 promoter. In addition, we observed a significant overlap in the protein expression pattern of hypoxia inducible factor-1α and DDX3 in MDA-MB-231 xenograft tumors. Taken together, our results demonstrate, for the first time, the role of DDX3 as a hypoxia-inducible gene that exhibits enhanced expression through the interaction of hypoxia inducible factor-1 with hypoxia inducible factor-1 responsive elements in its promoter region.

  3. Expression of the genes dual oxidase 2, lipocalin 2 and regenerating islet-derived 1 alpha in Crohn's disease

    DEFF Research Database (Denmark)

    Csillag, C.; Nielsen, O.H.; Vainer, Ben

    2007-01-01

    colonoscopically from 33 CD patients and from 17 control subjects. All controls and 10 CD patients were medication-free at the time of colonoscopy. The Human Genome U133 Plus 2.0 GeneChip Array was used for gene profiling. Hybridization data were analysed with dChip software. Results were confirmed by real......-time reverse transcriptase polymerase chain reaction (RT-PCR). Protein product expression of selected genes was assessed by immunohistochemistry using the Envision+ visualization technique. RESULTS: The expression profile was not homogeneous with the statistical cut-point settings applied. In comparison......, fold change 3.9), codes for a mitogenic protein; this could not be confirmed by RT-PCR. Medication-free patients had no differentially expressed genes as compared with controls. Immunohistochemistry indicated that these proteins were produced by epithelial cells (REG1A, LCN2) and leucocytes (DUOX2...

  4. Forecasting the demand for health tourism in Asian countries using a GM(1,1)-Alpha model

    OpenAIRE

    Ya-Ling Huang

    2012-01-01

    The purpose – Accurately forecasting the demand for international health tourism is important to newly-emerging markets in the world. The aim of this study was presents a more suitable and accurate model for forecasting the demand for health tourism that should be more theoretically useful. Design – Applying GM(1,1) with adaptive levels of α (hereafter GM(1,1)-α model) to provide a concise prediction model that will improve the ability to forecast the demand for health tourism in Asian cou...

  5. Dexamethasone/1alpha-25-dihydroxyvitamin D3-treated dendritic cells suppress colitis in the SCID T-cell transfer model

    DEFF Research Database (Denmark)

    Pedersen, Anders Elm; Schmidt, Esben Gjerløff Wedebye; Gad, Monika

    2008-01-01

    severe combined immunodeficient (SCID) mice adoptively transferred with CD4(+) CD25(-) T cells from the development of wasting disease and colitis. We therefore established an in vitro test that could predict the in vivo function of DCs and improve strategies for the preparation of immunomodulatory DCs...... in this model. Based on these in vitro findings, we here evaluate three methods for DC generation including short-term and long-term IL-10 exposure or DC exposure to dexamethasone in combination with vitamin D3 (Dex/D3). All DCs resulted in lower CD4(+) CD25(-) T-cell enteroantigen-specific responses in vitro...

  6. HIF1-alpha overexpression indicates a good prognosis in early stage squamous cell carcinomas of the oral floor

    Directory of Open Access Journals (Sweden)

    Joos Ulrich

    2005-07-01

    Full Text Available Abstract Background Hypoxia-inducible factor 1 (HIF-1 is a transcription factor, which plays a central role in biologic processes under hypoxic conditions, especially concerning tumour angiogenesis. HIF-1α is the relevant, oxygen-dependent subunit and its overexpression has been associated with a poor prognosis in a variety of malignant tumours. Therefore, HIF-1α expression in early stage oral carcinomas was evaluated in relation to established clinico-pathological features in order to determine its value as a prognostic marker. Methods 85 patients with histologically proven surgically treated T1/2 squamous cell carcinoma (SCC of the oral floor were eligible for the study. Tumor specimens were investigated by means of tissue micro arrays (TMAs and immunohistochemistry for the expression of HIF-1. Correlations between clinical features and the expression of HIF-1 were evaluated by Kaplan-Meier curves, log-rank tests and multivariate Cox regression analysis. Results HIF-1α was frequently overexpressed in a probably non-hypoxia related fashion. The expression of HIF-1α was related with a significantly improved 5-year survival rate (p Conclusion HIF-1α overexpression is an indicator of favourable prognosis in T1 and T2 SCC of the oral floor. Node negative patients lacking HIF-1α expression may therefore be considered for adjuvant radiotherapy.

  7. The protective effect of 1alpha, 25-dihydroxyvitamin d3 and metformin on liver in type 2 diabetic rats.

    Science.gov (United States)

    Elattar, Samah; Estaphan, Suzanne; Mohamed, Enas A; Elzainy, Ahmed; Naguib, Mary

    2017-10-01

    There is an accumulating evidence suggesting an immunomodulatory role of 1α,25(OH) 2 D3. Altered 1α,25(OH) 2 D3 level may play a role in the development of T2DM and contribute to the pathogenesis of liver diseases. Our study was designed to study and compare the effect of metformin and 1α,25(OH) 2 D3 supplementation on liver injury in type 2 diabetic rat. Sixty male Albino rats were divided into 5 groups; group 1: control rats. the remaining rats were fed high fat diet for 2 weeks and injected with streptozotocin (35mg/kg BW, i.p.) to induce T2DM and were divided into: group 2: untreated diabetic rats, group 3: diabetic rats treated by metformin (100mg/kgBW/d, orally), group 4: diabetic rats supplemented by 1α,25(OH) 2 D3 (0.5μg/kg BW, i.p.) 3 times weekly and group 5: supplemented by both 1α,25(OH) 2 D3 and metformin. Eight weeks later, serum glucose and insulin levels were measured, HOMA IR was calculated, lipid profile, Ca2+, ALT and AST were estimated. Liver specimens were taken to investigate PPAR-α (regulator of lipid metabolism), NF-κB p65, caspase 3 and PCNA (proliferating cell nuclear antigen) and for histological examination. The liver enzymes were elevated in the diabetic rats and the histological results revealed an injurious effect of diabetes on the liver. 1α,25(OH) 2 D3, metformin and both drugs treatment significantly improved liver enzymes as compared to the untreated rats. The improvement was associated with a significant improvement in the glycemic control, lipid profile and serum Ca2+ with a significant reduction in NF-κB p65 and caspase 3 and increased PPAR-α, and PCNA expression as compared to the untreated group. 1α,25(OH) 2 D3 induced a slightly better effect as compared to metformin. Both agents together had a synergistic action and almost completely protected the liver. Histological results confirmed the biochemical findings. Our results showed a protective effect of 1α,25(OH) 2 D3 and metformin on liver in diabetic rats as indicated by an improvement of the level of the liver enzymes, decreased apoptosis and increased proliferation and this was confirmed histologically, with modulating NFkB and PPAR-α. Both agents together had a synergistic effect. Copyright © 2016 Elsevier Ltd. All rights reserved.

  8. Incorporation of stromal cell-derived factor-1 alpha in PCL/gelatin electrospun membranes for guided bone regeneration

    NARCIS (Netherlands)

    Ji, W.; Yang, F.; Ma, J.L.; Bouma, M.J.; Boerman, O.C.; Chen, Z.; Beucken, J.J.J.P van den; Jansen, J.A.

    2013-01-01

    The goal of this work was to evaluate the effect of membrane functionalization with a chemotactic factor on cell recruitment and bone formation in order to develop a bioactive membrane for guided bone regeneration (GBR) applications. To this end. GBR membranes were prepared by electrospinning using

  9. Autoantibodies to IL-1 alpha in sera from umbilical cords, children, and adults, and from patients with juvenile chronic arthritis

    DEFF Research Database (Denmark)

    Müller, K; Hansen, M B; Zak, M

    1996-01-01

    umbilical cords (n = 11), children (n = 45), and adults (n = 20), as well as in 51 patients with juvenile chronic arthritis (JCA) of pauciarticular (n = 34), polyarticular (n = 8), or systemic onset type (n = 9). RESULTS. The frequency of positive sera was significantly lower in children than in cord blood...

  10. Elongation factor 1 alpha1 and genes associated with Usher syndromes are downstream targets of GBX2.

    Directory of Open Access Journals (Sweden)

    David A Roeseler

    Full Text Available Gbx2 encodes a DNA-binding transcription factor that plays pivotal roles during embryogenesis. Gain-and loss-of-function studies in several vertebrate species have demonstrated a requirement for Gbx2 in development of the anterior hindbrain, spinal cord, inner ear, heart, and neural crest cells. However, the target genes through which GBX2 exerts its effects remain obscure. Using chromatin immunoprecipitation coupled with direct sequencing (ChIP-Seq analysis in a human prostate cancer cell line, we identified cis-regulatory elements bound by GBX2 to provide insight into its direct downstream targets. The analysis revealed more than 286 highly significant candidate target genes, falling into various functional groups, of which 51% are expressed in the nervous system. Several of the top candidate genes include EEF1A1, ROBO1, PLXNA4, SLIT3, NRP1, and NOTCH2, as well as genes associated with the Usher syndrome, PCDH15 and USH2A, and are plausible candidates contributing to the developmental defects in Gbx2(-/- mice. We show through gel shift analyses that sequences within the promoter or introns of EEF1A1, ROBO1, PCDH15, USH2A and NOTCH2, are directly bound by GBX2. Consistent with these in vitro results, analyses of Gbx2(-/- embryos indicate that Gbx2 function is required for migration of Robo1-expressing neural crest cells out of the hindbrain. Furthermore, we show that GBX2 activates transcriptional activity through the promoter of EEF1A1, suggesting that GBX2 could also regulate gene expression indirectly via EEF1A. Taken together, our studies show that GBX2 plays a dynamic role in development and diseases.

  11. Variants in the interleukin-1 alpha and beta genes, and the risk for periodontal disease in dogs.

    Science.gov (United States)

    Albuquerque, C; Morinha, F; Magalhães, J; Requicha, J; Dias, I; Guedes-Pinto, H; Bastos, E; Viegas, C

    2015-12-01

    Elevated levels of interleukin-1 (IL-1) have been shown to amplify the inflammatory response against periodontopathogenic bacteria.In humans,polymorphisms in the IL1A and IL1B genes are the most well-studied genetic polymorphisms associated with periodontal disease (PD). In contrast to human, there is a lack of knowledge on the genetic basis of canine PD. A case-control study was conducted in which a molecular analysis of dog IL1A and IL1B genes was performed. Of the eight genetic variants identified, seven in IL1A gene and one in IL1B gene, IL1A/1_g.388A>C and IL1A /1_g.521T>A showed statistically significant differences between groups (adjusted OR (95% CI): 0.15 (0.03-0.76),P=0.022; 5.76 (1.03-32.1),P=0.046, respectively). It suggests that in the studied population the IL1A/1_g.388C allele is associated with a decreased PD risk, whereas the IL1A/1_g.521A allele can confer an increased risk. Additionally, the IL1A/2_g.515G>T variation resulted in a change of amino acid, i.e. glycine to valine. In silico analysis suggests that this change can alter protein structure and function, predicting it to be deleterious or damaging. This work suggests that IL1 genetic variants may be important in PD susceptibility in canines.

  12. A fasting inducible switch modulates gluconeogenesis via activator/coactivator exchange

    DEFF Research Database (Denmark)

    Liu, Yi; Dentin, Renaud; Chen, Danica

    2008-01-01

    During early fasting, increases in skeletal muscle proteolysis liberate free amino acids for hepatic gluconeogenesis in response to pancreatic glucagon. Hepatic glucose output diminishes during the late protein-sparing phase of fasting, when ketone body production by the liver supplies compensatory...... expression through the dephosphorylation and nuclear shuttling of forkhead box O1 (FOXO1). Here we show that a fasting-inducible switch, consisting of the histone acetyltransferase p300 and the nutrient-sensing deacetylase sirtuin 1 (SIRT1), maintains energy balance in mice through the sequential induction...... of CRTC2 and FOXO1. After glucagon induction, CRTC2 stimulated gluconeogenic gene expression by an association with p300, which we show here is also activated by dephosphorylation at Ser 89 during fasting. In turn, p300 increased hepatic CRTC2 activity by acetylating it at Lys 628, a site that also...

  13. The impact of language co-activation on L1 and L2 speech fluency

    NARCIS (Netherlands)

    Bergmann, Christopher; Sprenger, Simone A.; Schmid, Monika S.

    2015-01-01

    Fluent speech depends on the availability of well-established linguistic knowledge and routines for speech planning and articulation. A lack of speech fluency in late second-language (12) learners may point to a deficiency of these representations, due to incomplete acquisition. Experiments on

  14. Leptin recruits Creb-regulated transcriptional coactivator 1 to improve hyperglycemia in insulin-deficient diabetes

    Directory of Open Access Journals (Sweden)

    Geun Hyang Kim

    2015-03-01

    Conclusions: Our study reveals that Crtc1 functions as a conduit for leptin's glucoregulatory actions in insulin-dependent diabetes. This study also highlights a new role for Crtc1 in modulating peripheral glucose metabolism.

  15. Activation of Basal Gluconeogenesis by Coactivator p300 Maintains Hepatic Glycogen Storage

    Science.gov (United States)

    Cao, Jia; Meng, Shumei; Ma, Anlin; Radovick, Sally; Wondisford, Fredric E.

    2013-01-01

    Because hepatic glycogenolysis maintains euglycemia during early fasting, proper hepatic glycogen synthesis in the fed/postprandial states is critical. It has been known for decades that gluconeogenesis is essential for hepatic glycogen synthesis; however, the molecular mechanism remains unknown. In this report, we show that depletion of hepatic p300 reduces glycogen synthesis, decreases hepatic glycogen storage, and leads to relative hypoglycemia. We previously reported that insulin suppressed gluconeogenesis by phosphorylating cAMP response element binding protein-binding protein (CBP) at S436 and disassembling the cAMP response element-binding protein-CBP complex. However, p300, which is closely related to CBP, lacks the corresponding S436 phosphorylation site found on CBP. In a phosphorylation-competent p300G422S knock-in mouse model, we found that mutant mice exhibited reduced hepatic glycogen content and produced significantly less glycogen in a tracer incorporation assay in the postprandial state. Our study demonstrates the important and unique role of p300 in glycogen synthesis through maintaining basal gluconeogenesis. PMID:23770612

  16. Function of an Androgen Receptor Coactivator Regulated in Prostate Development and Prostate Cancer

    National Research Council Canada - National Science Library

    Logan, Susan K; Taneja, Samir; Garabedian, Michael; Dynlacht, Brian; Lee, Peng; Ha, Susan

    2005-01-01

    .... Our aims are to identify ART-27-dependent AR-target genes involved in growth suppression and differentiation and to elucidate the mechanism of regulation of ART-27 expression in prostate cancer...

  17. Involvement of the Transcriptional Coactivator ThMBF1 in the Biocontrol Activity of Trichoderma harzianum

    Directory of Open Access Journals (Sweden)

    M. Belén Rubio

    2017-11-01

    Full Text Available Trichoderma harzianum is a filamentous fungus well adapted to different ecological niches. Owing to its ability to antagonize a wide range of plant pathogens, it is used as a biological control agent in agriculture. Selected strains of T. harzianum are also able to increase the tolerance of plants to biotic and abiotic stresses. However, little is known about the regulatory elements of the T. harzianum transcriptional machinery and their role in the biocontrol by this species. We had previously reported the involvement of the transcription factor THCTF1 in the T. harzianum production of the secondary metabolite 6-pentyl-pyrone, an important volatile compound related to interspecies cross-talk. Here, we performed a subtractive hybridization to explore the genes regulated by THCTF1, allowing us to identify a multiprotein bridging factor 1 (mbf1 homolog. The gene from T. harzianum T34 was isolated and characterized, and the generated Thmbf1 overexpressing transformants were used to investigate the role of this gene in the biocontrol abilities of the fungus against two plant pathogens. The transformants showed a reduced antifungal activity against Fusarium oxysporum f. sp. lycopersici race 2 (FO and Botrytis cinerea (BC in confrontation assays on discontinuous medium, indicating that the Thmbf1 gene could affect T. harzianum production of volatile organic compounds (VOC with antifungal activity. Moreover, cellophane and dialysis membrane assays indicated that Thmbf1 overexpression affected the production of low molecular weight secreted compounds with antifungal activity against FO. Intriguingly, no correlation in the expression profiles, either in rich or minimal medium, was observed between Thmbf1 and the master regulator gene cross-pathway control (cpc1. Greenhouse assays allowed us to evaluate the biocontrol potential of T. harzianum strains against BC and FO on susceptible tomato plants. The wild type strain T34 significantly reduced the necrotic leaf lesions caused by BC while plants treated with the Thmbf1-overexpressing transformants exhibited an increased susceptibility to this pathogen. The percentages of Fusarium wilt disease incidence and values of aboveground dry weight showed that T34 did not have biocontrol activity against FO, at least in the ‘Moneymaker’ tomato variety, and that Thmbf1 overexpression increased the incidence of this disease. Our results show that the Thmbf1 overexpression in T34 negatively affects its biocontrol mechanisms.

  18. Disrupted Co-activation of Interneurons and Hippocampal Network after Focal Kainate Lesion

    Directory of Open Access Journals (Sweden)

    Lim-Anna Sieu

    2017-11-01

    Full Text Available GABAergic interneurons are known to control activity balance in physiological conditions and to coordinate hippocampal networks during cognitive tasks. In temporal lobe epilepsy interneuron loss and consecutive network imbalance could favor pathological hypersynchronous epileptic discharges. We tested this hypothesis in mice by in vivo unilateral epileptogenic hippocampal kainate lesion followed by in vitro recording of extracellular potentials and patch-clamp from GFP-expressing interneurons in CA3, in an optimized recording chamber. Slices from lesioned mice displayed, in addition to control synchronous events, larger epileptiform discharges. Despite some ipsi/contralateral and layer variation, interneuron density tended to decrease, average soma size to increase. Their membrane resistance decreased, capacitance increased and contralateral interneuron required higher current intensity to fire action potentials. Examination of synchronous discharges of control and larger amplitudes, revealed that interneurons were biased to fire predominantly with the largest population discharges. Altogether, these observations suggest that the overall effect of reactive cell loss, hypertrophy and reduced contralateral excitability corresponds to interneuron activity tuning to fire with larger population discharges. Such cellular and network mechanisms may contribute to a runaway path toward epilepsy.

  19. Involvement of the Transcriptional Coactivator ThMBF1 in the Biocontrol Activity of Trichoderma harzianum.

    Science.gov (United States)

    Rubio, M Belén; Pardal, Alonso J; Cardoza, Rosa E; Gutiérrez, Santiago; Monte, Enrique; Hermosa, Rosa

    2017-01-01

    Trichoderma harzianum is a filamentous fungus well adapted to different ecological niches. Owing to its ability to antagonize a wide range of plant pathogens, it is used as a biological control agent in agriculture. Selected strains of T. harzianum are also able to increase the tolerance of plants to biotic and abiotic stresses. However, little is known about the regulatory elements of the T. harzianum transcriptional machinery and their role in the biocontrol by this species. We had previously reported the involvement of the transcription factor THCTF1 in the T. harzianum production of the secondary metabolite 6-pentyl-pyrone, an important volatile compound related to interspecies cross-talk. Here, we performed a subtractive hybridization to explore the genes regulated by THCTF1, allowing us to identify a multiprotein bridging factor 1 ( mbf1 ) homolog. The gene from T. harzianum T34 was isolated and characterized, and the generated Thmbf1 overexpressing transformants were used to investigate the role of this gene in the biocontrol abilities of the fungus against two plant pathogens. The transformants showed a reduced antifungal activity against Fusarium oxysporum f. sp. lycopersici race 2 (FO) and Botrytis cinerea (BC) in confrontation assays on discontinuous medium, indicating that the Thmbf1 gene could affect T. harzianum production of volatile organic compounds (VOC) with antifungal activity. Moreover, cellophane and dialysis membrane assays indicated that Thmbf1 overexpression affected the production of low molecular weight secreted compounds with antifungal activity against FO. Intriguingly, no correlation in the expression profiles, either in rich or minimal medium, was observed between Thmbf1 and the master regulator gene cross-pathway control ( cpc1 ). Greenhouse assays allowed us to evaluate the biocontrol potential of T. harzianum strains against BC and FO on susceptible tomato plants. The wild type strain T34 significantly reduced the necrotic leaf lesions caused by BC while plants treated with the Thmbf1 -overexpressing transformants exhibited an increased susceptibility to this pathogen. The percentages of Fusarium wilt disease incidence and values of aboveground dry weight showed that T34 did not have biocontrol activity against FO, at least in the 'Moneymaker' tomato variety, and that Thmbf1 overexpression increased the incidence of this disease. Our results show that the Thmbf1 overexpression in T34 negatively affects its biocontrol mechanisms.

  20. Co-activation of AMPK and mTORC1 Induces Cytotoxicity in Acute Myeloid Leukemia

    Directory of Open Access Journals (Sweden)

    Pierre Sujobert

    2015-06-01

    Full Text Available AMPK is a master regulator of cellular metabolism that exerts either oncogenic or tumor suppressor activity depending on context. Here, we report that the specific AMPK agonist GSK621 selectively kills acute myeloid leukemia (AML cells but spares normal hematopoietic progenitors. This differential sensitivity results from a unique synthetic lethal interaction involving concurrent activation of AMPK and mTORC1. Strikingly, the lethality of GSK621 in primary AML cells and AML cell lines is abrogated by chemical or genetic ablation of mTORC1 signaling. The same synthetic lethality between AMPK and mTORC1 activation is established in CD34-positive hematopoietic progenitors by constitutive activation of AKT or enhanced in AML cells by deletion of TSC2. Finally, cytotoxicity in AML cells from GSK621 involves the eIF2α/ATF4 signaling pathway that specifically results from mTORC1 activation. AMPK activation may represent a therapeutic opportunity in mTORC1-overactivated cancers.

  1. The metazoan Mediator co-activator complex as an integrative hub for transcriptional regulation

    OpenAIRE

    Malik, Sohail; Roeder, Robert G.

    2010-01-01

    The Mediator is an evolutionarily conserved, multiprotein complex that is a key regulator of protein-coding genes. In metazoan cells, multiple pathways that are responsible for homeostasis, cell growth and differentiation converge on the Mediator through transcriptional activators and repressors that target one or more of the almost 30 subunits of this complex. Besides interacting directly with RNA polymerase II, Mediator has multiple functions and can interact with and coordinate the action ...

  2. Characterization of a Novel Nuclear Hormone Receptor Coactivator, Uba3, and Its Function in Breast Cancer

    National Research Council Canada - National Science Library

    Dennis, Andrew

    2001-01-01

    .... Interestingly, hUba3 and APP-BP1 appear not to contain appreciable intrinsic activation functions nor demonstrate physical iii vitro associations with PR-B, suggesting these proteins may differ...

  3. Characterization of a Novel Nuclear Hormone Receptor Coactivator, Uba3, and Its Function in Breast Cancer

    National Research Council Canada - National Science Library

    Dennis, Andrew

    2001-01-01

    .... Human Uba3, as well as its hetero-dimeric binding partner, APP-BP 1, were able to enhance ligand- activated ERoc, PR-B, GR, AR, TRBeta, and RARalpha-dependent transcription in HeLa cells, although...

  4. The Transcriptional Coactivator Bob1 Is Associated With Pathologic B Cell Responses in Autoimmune Tissue Inflammation

    NARCIS (Netherlands)

    Levels, Maria J.; Van Tok, Melissa N.; Cantaert, Tineke; Canete, Juan D.; Kroese, Frans G. M.; Germar, Kristine; Spits, Hergen; Baeten, Dominique L. P.; Yeremenko, Nataliya G.

    Objective. The molecular mechanisms steering abnormal B cell responses in autoimmune diseases remain poorly understood. We undertook this study to identify molecular switches controlling pathologic B cell responses in rheumatoid arthritis (RA). Methods. Candidate molecules were identified by gene

  5. Muscle Coactivation during Stability Exercises in Rhythmic Gymnasti